JP5929377B2 - toner - Google Patents

Description

  The present invention relates to a toner.

  In recent years, in the field of electrophotographic image forming technology, development competition of color image forming apparatuses capable of high-speed image formation and high image quality has intensified. For this reason, in order to obtain a full-color image at a high speed, a plurality of electrophotographic photosensitive members are arranged in series in the image forming method, and an image for each color component is formed on each electrophotographic photosensitive member, and is superimposed on the intermediate transfer member. Many so-called tandem systems that perform batch transfer onto a recording material have been employed (see, for example, Patent Document 1 and Patent Document 2). When an intermediate transfer member is used, if background stains occur on the electrophotographic photosensitive member during development, there is an effect of preventing the background stains from being transferred directly to a recording material such as paper. The system to be used passes through two transfer processes: a transfer process from an electrophotographic photosensitive member to an intermediate transfer body (primary transfer) and a transfer process to obtain a final image from the intermediate transfer body (secondary transfer). Therefore, there is a problem that transfer efficiency is lowered.

  On the other hand, in addition to the above problems, there is a demand for higher-quality full-color image formation, and developers have been designed for higher image quality. In order to meet the demand for higher image quality, particularly full-color image quality, toners are increasingly becoming smaller in particle size and are being studied to faithfully reproduce latent images. In order to reduce the particle size, a toner manufacturing method using a polymerization method has been proposed as a means for controlling the toner to a desired toner shape and surface structure (for example, Patent Document 3 and Patent Document 3). 4). In the case of the polymerization toner, in addition to controlling the particle size of the toner particles, shape control is possible. In addition, by reducing the particle size together with this, the reproducibility of dots and fine lines can be improved, the pile height (image layer thickness) can be lowered, and higher image quality can be expected.

  However, when a small particle size toner is used, the non-electrostatic adhesion force between the toner particles and the electrophotographic photosensitive member or between the toner particles and the intermediate transfer member is increased, so that the transfer efficiency is likely to further decrease. For this reason, when a small particle size toner is used in a high-speed full-color image forming apparatus, there is a problem that a decrease in transfer efficiency particularly in secondary transfer becomes significant. The reason for this is that non-electrostatic adhesion to the intermediate transfer member per toner particle is increasing due to the reduction in toner particle size, and in the secondary transfer, a plurality of color toners are superimposed. This is because the time during which the toner particles are subjected to the transfer electric field at the nip portion of the secondary transfer is shortened as the speed is increased, which makes it difficult to transfer the toner particles.

  In order to cope with the above problem, it is conceivable to further increase the transfer electric field of the secondary transfer. However, if the transfer electric field is excessively increased, the transfer efficiency is lowered and there is a limit. In addition, it is conceivable to increase the time during which the toner particles are subjected to the transfer electric field by increasing the width of the nip portion of the secondary transfer. However, in the case of a contact-type voltage application method such as a bias roller, the nip width is increased. The only way to do this is to increase the contact pressure of the bias roller or increase the roller diameter of the bias roller. Increasing the contact pressure has a limit due to the relationship with the image quality, and increasing the roller diameter has a limit due to the relationship with the downsizing of the apparatus. Further, in the case of a non-contact voltage application method using a charger or the like, there is a limit because the nip width of secondary transfer must be increased by increasing the number of chargers. For this reason, it can be said that it is practically impossible to increase the nip width until a transfer efficiency higher than this is obtained, particularly in a high-speed machine.

  In contrast, as a means for reducing the non-electrostatic adhesion between the toner particles and the electrophotographic photosensitive member, or between the toner particles and the intermediate transfer member, the type and amount of the additive are adjusted (especially addition with a large particle size) A method of adding an agent has been proposed (see, for example, Patent Document 5 and Patent Document 6). By this method, the toner particles can obtain the effect of reducing the non-electrostatic adhesion force and improve the transfer efficiency, and also can obtain the effects of improving the development stability and cleaning.

  Initially, the toner particles described above can improve the transfer efficiency of the image forming apparatus. However, if the toner is subjected to mechanical stress such as stirring for a long time in the developing device of the image forming apparatus, the additive is buried in the toner base, and the effect of reducing the adhesive force by the additive is not exhibited, The transfer efficiency of the image forming apparatus is reduced. In particular, in the case of a high-speed machine, since stirring in the developing device is intense, this mechanical stress is large, and the embedding of the additive in the toner base is easily accelerated. For this reason, it is assumed that transfer efficiency is lowered at a relatively early stage.

  For this reason, in order to maintain high transfer efficiency stably over a long period of time on a high-speed machine, the surface properties of the toner must be such that the additive can be present on the surface without being embedded in the toner base even under mechanical stress. It is necessary to control (mechanical strength). Furthermore, if the surface property (mechanical strength) of the toner is too strong (hard), the toner melts during fixing, or in the case of a toner containing a release agent such as wax, a fixing roller during fixing. It is also necessary to pay attention to the side effect that the release of the release agent to the ink becomes insufficient and the fixing property deteriorates.

  In recent years, the market demands low-temperature fixing for energy saving. In particular, for energy saving, the waiting time (the apparatus warm-up time) from when the image forming apparatus is ready to use until image formation is possible. In order to reduce the amount of power required for the above) as much as possible, there is a strong demand for shortening the standby time. As a means for solving this problem, a low-temperature fixing toner using a low-melting-point toner binder has been proposed. On the other hand, such a toner may have a trade-off between heat resistance and environmental stability. In particular, under high temperature and high humidity, loose aggregation between particles sometimes occurs, which may adversely affect toner transfer performance.

  An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention improves transfer efficiency, achieves both low-temperature fixability and hot offset resistance in a high-speed full-color image forming method and apparatus, eliminates image defects during each transfer, and has good long-term reproducibility. An object of the present invention is to provide a toner that outputs an image.

Means for solving the problems are as follows.
A toner for solving the above problems has toner base particles containing at least a polyester resin, styrene-acrylic resin fine particles A formed on the toner base particles, and a surface layer containing the acrylic resin fine particles B. And the outermost surface layer formed from the styrene-acrylic resin fine particles A, the styrene-acrylic resin fine particles A have a hydrophobicity of 60 to 80%, and the acrylic resin fine particles B have a hydrophobicity of 70 to 70%. 90% , and the volume average particle diameter of the acrylic resin fine particles B is 10 to 52 nm .
Such a toner includes, for example, a step a in which a toner material containing at least a polyester resin is dissolved or dispersed in an organic solvent to prepare a toner material dissolved or dispersed liquid, and the toner material dissolved or dispersed liquid is at least styrene-acrylic. Step b of adding and emulsifying or dispersing in an aqueous medium containing resin fine particles A and acrylic resin fine particles B to create an emulsified or dispersed liquid, and removing the organic solvent from the emulsified or dispersed liquid to produce toner particles. A toner produced by including the step c, wherein the styrene-acrylic resin fine particles A have a hydrophobicity of 60 to 80% and the acrylic resin fine particles B have a hydrophobicity of 70 to 90%. Is preferred.
Such toner includes, for example, a step a in which a toner material containing at least a polyester resin is dissolved or dispersed in an organic solvent to prepare a toner material dissolved or dispersed, and the toner material dissolved or dispersed in at least styrene. A step b of adding an emulsion into an aqueous medium containing the acrylic resin fine particles A and the acrylic resin fine particles B and emulsifying or dispersing to create an emulsion or dispersion; and removing the organic solvent from the emulsion or dispersion to obtain toner particles. Including the step c of producing, wherein the degree of hydrophobicity of the styrene-acrylic resin fine particles A is 60 to 80% and the degree of hydrophobicity of the acrylic resin fine particles B is 70 to 90%. it can.
The developer provided by the present invention contains the toner described above.
The toner-containing container provided by the present invention contains the toner described above.
A full-color image forming method provided by the present invention includes a charging step of charging an electrophotographic photosensitive member by a charging unit, an exposure step of forming an electrostatic latent image on the charged electrophotographic photosensitive member by an exposing unit, A developing step of forming a toner image on the electrophotographic photosensitive member on which the electrostatic latent image is formed by a developing unit containing toner; and an intermediate transfer member that transfers the toner image formed on the electrophotographic photosensitive member by a primary transfer unit. A primary transfer step of transferring the toner image onto the intermediate transfer member; a secondary transfer step of transferring the toner image transferred onto the intermediate transfer member onto the recording material by a secondary transfer means; and a heat transfer of the toner image transferred onto the recording material. And a fixing process including fixing on a recording material by a fixing means including a pressure fixing member, and a transfer residual toner attached to the surface of the electrophotographic photosensitive member having the toner image transferred onto the intermediate transfer member by the primary transfer means And a cleaning step of cleaning by the cleaning unit, the toner in the developing step are those wherein the toner described above.
The process cartridge provided by the present invention integrally includes at least an electrophotographic photosensitive member and developing means for converting the electrostatic latent image formed on the electrophotographic photosensitive member into a toner image with the toner described above. The image forming apparatus main body is detachable.
An image forming apparatus provided by the present invention includes an electrophotographic photosensitive member, a charging unit that charges the electrophotographic photosensitive member, an exposure unit that forms an electrostatic latent image on the charged electrophotographic photosensitive member, Development means for converting the electrostatic latent image formed on the electrophotographic photosensitive member into a toner image with the toner described above, and the toner image formed on the electrophotographic photosensitive member via an intermediate transfer member or via A transfer means for transferring the toner image onto the recording material, a fixing means for fixing the toner image transferred onto the recording material onto the recording material with a heat and pressure fixing member, and an intermediate transfer member or And cleaning means for cleaning the transfer residual toner adhering to the surface of the electrophotographic photosensitive member after being transferred onto the recording material.

  According to the present invention, the conventional problems can be solved and the object can be achieved. In a high-speed full-color image forming method, transfer efficiency is improved and both low-temperature fixability and hot offset resistance are achieved. In addition, it is possible to provide a toner that eliminates image defects at the time of each transfer and outputs a long-term reproducible image, a toner-filled container filled with the toner, a full-color image forming method, a process cartridge, and an image forming apparatus. Further, the toner of the present invention is transferred twice, that is, a transfer process (primary transfer) from an electrophotographic photosensitive member to an intermediate transfer member and a transfer process (secondary transfer) onto a recording material for obtaining a final image from the intermediate transfer member. It has the effect that it can be used suitably in the electrophotographic apparatus which passes through a process.

FIG. 3 is a schematic diagram showing a structure of a toner of the present invention. (A) is a photomicrograph of the toner of the present invention, and (b) is an enlarged view of the area indicated by the broken line in (a). It is a schematic block diagram of an example of a contact-type roller charging device. It is a schematic block diagram of an example of a contact-type brush charging device. It is a schematic block diagram of an example of a developing device. FIG. 2 is a schematic configuration diagram of an example of a fixing device. FIG. 3 is a diagram illustrating a layer configuration of a fixing belt. It is a schematic block diagram of an example of a process cartridge. 1 is a schematic configuration diagram of an example of an image forming apparatus. It is a schematic block diagram of the other example of an image forming apparatus.

(toner)
The toner of the present invention comprises toner base particles containing at least a polyester resin, a surface layer containing styrene-acrylic resin fine particles A and acrylic resin fine particles B formed on the toner base particles, and the styrene -It has the outermost surface layer formed from the acrylic resin fine particles A, the degree of hydrophobicity of the styrene-acrylic resin fine particles A is 60 to 80%, and the degree of hydrophobicity of the acrylic resin fine particles B is 70 to 90% . The volume average particle size of the acrylic resin fine particles B is 10 to 52 nm .
The constituent material of the toner of the present invention contains toner base particles, styrene-acrylic resin fine particles A, and acrylic resin fine particles B, and if necessary, a colorant, a release agent (wax), and inorganic fine particles. And other components such as an external additive such as a fluidity improver and a cleaning property improver.
The toner of the present invention includes a layer formed from the resin fine particles A as the outermost surface layer on the surface of the toner base particles, and the resin fine particles B formed on the inner side of the layer. preferable.
Hereinafter, the toner of the present invention will be described in detail.

As shown in FIG. 1, the toner of the present invention has acrylic resin fine particles B attached to the surface of toner base particles having a toner material centered on a polyester resin as a binder resin and a colorant. Styrene-acrylic resin fine particles A are adhered to the outside (in other words, a coating layer is formed). FIG. 2 is a photomicrograph of the toner of the present invention.
In the toner of the present invention, preferably, the volume average particle diameter of the acrylic resin fine particles B is larger than the volume average particle diameter of the styrene-acrylic resin fine particles A. That is, the styrene-acrylic resin fine particles A are Since the particle diameter (5 to 50 nm) is small, it is buried in the toner base particles or adhered between the toner base particles and the acrylic resin fine particles B (volume average particle diameter: 10 to 52 nm ). Therefore, if the toner is not observed very finely, the toner appears to have the acrylic resin fine particles B attached to the surface of the toner base particles. The volume average particle diameter of the toner is adjusted by emulsification or dispersion conditions such as stirring of the aqueous medium in the emulsification step.

Usually, in the electrophotographic image forming apparatus, when a small particle size toner is used, the non-electrostatic adhesion force between the toner particles and the electrophotographic photosensitive member or between the toner particles and the intermediate transfer member is increased. The transfer efficiency is further reduced. In particular, when a small-diameter toner is used in a high-speed machine, non-electrostatic adhesion to the intermediate transfer member is increased by reducing the particle diameter of the toner, and the transfer nip portion, It is known that the transfer efficiency in the secondary transfer is significantly reduced because the time during which the toner particles are subjected to the transfer electric field in the nip portion of the secondary transfer is shortened.
However, in the toner manufactured by the manufacturing method of the present invention, the large particle size (acrylic resin particle B) adheres to the surface of the toner base particle, and this large particle size particle is somewhat or sufficient. By having the hardness, the non-electrostatic adhesion force of the toner particles is reduced, and even when the transfer time is shortened as in a high-speed machine, sufficient transfer efficiency can be obtained without hindering fixing properties. it can. Further, since the acrylic resin fine particles B have a certain or sufficient hardness, the acrylic resin fine particles B adhering to the surface of the toner base particles are used in the toner even when the mechanical stress with time is large as in a high-speed machine. Since it can continue to exist without being buried in it, it is possible to maintain sufficient transfer efficiency even in the long term. At the same time, it is possible to prevent the external additive from adhering to the toner surface from being buried.

As described above, in the toner of the present invention, the degree of hydrophobicity of the styrene-acrylic resin fine particles A needs to be 60 to 80%, and the degree of hydrophobicity of the acrylic resin fine particles B needs to be 70 to 90%. is there.
Here, the degree of hydrophobicity is obtained as follows.

[Calculation method for degree of hydrophobicity]
The degree of hydrophobicity of the styrene-acrylic resin fine particles A and the acrylic resin fine particles B can be measured using a methanol dropping transmittance curve. As a measuring device, for example, a powder wettability tester WET-100P manufactured by REHSCA (Resca) can be used, and examples of specific measuring operations include the methods exemplified below.
When the sample as the specimen is in an emulsion form, the liquid is removed by drying at room temperature. After drying, the sample is washed with the solvent used in the emulsion to remove the surfactant or dispersant. What performed these processes is used for a measurement.
First, 70 ml of a hydrated methanol solution composed of 60% by volume of methanol and 40% by volume of water is placed in a container and dispersed with an ultrasonic disperser for 5 minutes to remove bubbles and the like in the solution.
In this solution, 0.025 g of a sample as a specimen is added and suspended to prepare a sample solution for measuring hydrophobic characteristics. As a container for preparing and measuring a sample solution, a glass flask having a circular diameter of 5 cm and a height of 88 mm can be used.
Next, while stirring the prepared sample solution for measurement at a speed of 6.67 s-1, methanol was added at 1.3 ml / min. The sample is suspended and dispersed in the solvent. While dropping methanol, the transmitted light intensity of light having a wavelength of 780 nm of the measurement sample is measured to obtain the transmittance, and a methanol dropping transmittance curve is created. Here, the stirring can be performed using a magnetic stirrer (for example, a spindle having a length of 25 mm and a maximum diameter of 8 mm and having a Teflon (registered trademark) coating).
In the measurement of the degree of hydrophobicity by methanol wettability, when the degree of hydrophobicity of a sample as a specimen is less than 60%, the specimen is added to a water-containing methanol solution composed of 60 volume% methanol and 40 volume% water. Then, it will disperse | distribute immediately in a solvent and a transmittance | permeability curve cannot be calculated | required. Therefore, when the degree of hydrophobicity of the sample as a specimen is less than 60%, the measurement was performed with the methanol concentration of the initial solution set to 0%.
In this way, the change in transmittance with respect to the methanol dropping amount is measured.
The result thus obtained is recalculated so that the translucency at the sedimentation start point is 100 and the translucency at the sedimentation end point is 0. The methanol concentration when the translucency is 50% is calculated as the degree of hydrophobicity (%) of the sample.

In order to make the degree of hydrophobicity of the styrene-acrylic resin fine particles A 60 to 80%, the molar ratio of monomers constituting these copolymers is appropriately changed, the crosslinking agent is selected, and / or the molecular weight is appropriately changed. Etc.
Further, the hydrophobicity of the acrylic resin fine particles B can be set to 70 to 90% by appropriately changing the molecular weight.

<Styrene-acrylic resin fine particles A>
The resin for the styrene-acrylic resin fine particles A is not particularly limited as long as it is a copolymer containing styrene and at least one of acrylic acid and (meth) acrylic acid ester. Can be selected as appropriate, and may be a thermoplastic resin or a thermosetting resin. Moreover, it is preferable that it is resin which can form an aqueous dispersion in an aqueous medium. Examples of the resin for the styrene-acrylic resin fine particles A include, for example, vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, melamine resin, urea resin, aniline resin. , Ionomer resin, polycarbonate resin and the like. These may be used individually by 1 type and may use 2 or more types together.
The vinyl resin is a polymer obtained by homopolymerization or copolymerization of a vinyl monomer. For example, a styrene-acrylic acid copolymer, a styrene- (meth) acrylic acid ester polymer, a styrene-butadiene copolymer, (meth) Acrylic acid-acrylic acid ester polymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, styrene- (meth) acrylic acid ester copolymer and the like can be mentioned. Among these, a styrene-acrylic acid copolymer and a styrene- (meth) acrylic acid ester polymer are preferable.
The styrene-acrylic resin fine particles A are preferably fine particles of a crosslinked resin or a non-crosslinked resin containing a styrene-acrylic acid copolymer or a styrene- (meth) acrylic acid ester polymer.

  The styrene-acrylic resin fine particles A are preferably incompatible with the polyester resin and swell in an organic solvent (ethyl acetate). As a method for controlling the swellability of the styrene-acrylic resin fine particles A with respect to an organic solvent (ethyl acetate), there are a crosslinking density and a constituent monomer.

  When the degree of hydrophobicity of the styrene-acrylic resin fine particles A is less than 60%, the anti-agglomeration performance may be lowered, and when it exceeds 80%, the dispersion stabilizing effect during production may not be obtained.

  The acid value of the styrene-acrylic resin fine particles A is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 130 mgKOH / g to 230 mgKOH / g, more preferably 170 mgKOH / g to 190 mgKOH / g. . When the acid value is less than 130 mgKOH / g, the dispersion stabilizing effect at the time of manufacture may not always be sufficient, and when it exceeds 230 mgKOH / g, the environmental stability of the toner charging ability deteriorates or the anti-aggregation performance May decrease. On the other hand, when the acid value is in the more preferred range, it is advantageous in terms of toner manufacturability, toner charging performance and anti-aggregation performance.

The weight average molecular weight (Mw) of the styrene-acrylic resin fine particles A is preferably 10,000 to 2,000,000, and more preferably 200,000 to 600,000.
When the weight average molecular weight is less than 10,000, the polymer tends to swell in an organic solvent or an aqueous medium, so that an aggregate is formed when the toner is fixed on the surface of the toner base particles, and the outermost layer on the surface of the toner base particles is formed. As a result, the formation of a layer composed of styrene-acrylic resin fine particles A may be hindered, and the acrylic resin fine particles B may not be sufficiently effective to prevent burying or movement due to mechanical stress. On the other hand, if the weight average molecular weight exceeds 2,000,000, the toner surface becomes too hard and the toner may not be sufficiently melted during heat fixing, so that the fixability may be deteriorated. On the other hand, when the weight average molecular weight is in the more preferable range, it is advantageous in terms of layer formation on the toner base surface and low-temperature fixing performance.

The volume average particle size of the styrene-acrylic resin fine particles A is preferably 5 nm to 50 nm, more preferably 10 nm to 25 nm, from the viewpoint of controlling the particle size and particle size distribution of the emulsified particles.
The volume average particle size and particle size distribution can be measured by, for example, SEM, TEM, light scattering method, and the like. Among these, it is preferable to measure by a laser scattering measurement method using a laser diffraction / scattering type particle size distribution measuring apparatus (LA-920 manufactured by Horiba, Ltd.). To measure.

The glass transition temperature (Tg) of the styrene-acrylic resin fine particles A is preferably 40 ° C to 100 ° C, more preferably 45 ° C to 80 ° C.
When the Tg is less than 40 ° C., the styrene-acrylic resin fine particles A on the toner surface are softened in the storage temperature range of the toner, and there is a possibility that an aggregate due to fusion between the toners is formed. On the other hand, if the Tg exceeds 100 ° C., the toner surface becomes too hard, and the toner may not be sufficiently melted at the time of heat fixing, so that the fixability may be deteriorated.

Here, the glass transition point (Tg) in the present invention is specifically determined by the following procedure. The measurement was performed under the following measurement conditions using TA-60WS and DSC-60 manufactured by Shimadzu Corporation.
〔Measurement condition〕
Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50ml / min)
(Temperature conditions)
Starting temperature: 20 ° C
Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
Holding time: None Temperature drop: 10 ° C / min
End temperature: 20 ° C
Holding time: None Temperature increase rate: 10 ° C / min
End temperature: 150 ° C

  The measurement results were analyzed using the data analysis software (TA-60, version 1.52) manufactured by Shimadzu Corporation. The analysis method specifies a range of ± 5 ° C around the point showing the maximum peak on the lowest temperature side of the DrDSC curve, which is the DSC differential curve of the second temperature rise, and uses the peak analysis function of the analysis software to specify the peak temperature Ask for. Next, the maximum endothermic temperature of the DSC curve is determined using the peak analysis function of the analysis software in the range of the peak temperature + 5 ° C. and −5 ° C. in the DSC curve. The temperature shown here corresponds to Tg of the resin of the measurement sample.

  In the production process of the toner of the present invention, the styrene-acrylic resin fine particles A adhere to the outside of the acrylic resin fine particles B adhering to the surface of the toner base particles, and are fused and fused to form the outermost surface of the toner base particles. A relatively hard layer composed of the styrene-acrylic resin fine particles A is formed as the surface layer.

By forming a layer made of the styrene-acrylic resin fine particles A as the outermost surface layer on the surface of the toner base particles, the acrylic resin fine particles B fixed on the surface of the toner base particles are formed on the inner side of the layer. It has the effect of preventing burying and moving due to mechanical stress.
In other words, a surface layer containing styrene-acrylic resin fine particles A and acrylic resin fine particles B is formed on the toner base particles, and the outermost surface (outermost surface layer) of this surface layer is a layer made of styrene-acrylic resin fine particles A. Is formed.

The styrene-acrylic resin fine particles A preferably have an anionic property in order not to aggregate the styrene-acrylic resin fine particles A when the aqueous medium in the toner production method of the present invention contains an anionic surfactant. Thereby, it adsorbs to the outermost shell of the droplet containing the toner material, and has an effect of suppressing coalescence of the droplets, and the particle size distribution of the toner can be controlled. Furthermore, negative chargeability of the toner can be imparted. In order to exert these effects, the styrene-acrylic resin fine particles A are made smaller than the acrylic resin fine particles B, and the volume average particle diameter is set to 5 nm to 50 nm.
The anionic styrene-acrylic resin fine particles A use an anionic surfactant in the preparation method of the styrene-acrylic resin fine particles A described later, or introduce anionic groups such as carboxylic acid groups and sulfonic acid groups into the resin. It can produce by doing.

-Anionic surfactant-
Examples of the anionic surfactant used for preparing the styrene-acrylic resin fine particles A include, for example, fatty acid salts, alkyl sulfate esters, alkyl aryl sulfonates, alkyl diaryl ether disulfonates, dialkyl sulfosuccinates, and alkyl phosphates. , Naphthalenesulfonic acid formalin condensate, polyoxyethylene alkyl phosphate ester salt, glyceryl borate fatty acid ester and the like.

[Method for Preparing Styrene-Acrylic Resin Fine Particle A]
The styrene-acrylic resin fine particles A can be obtained by polymerizing precursors such as monomers and oligomers constituting the resin for the styrene-acrylic resin fine particles A according to a known method appropriately selected according to the purpose. It is preferably obtained as an aqueous dispersion of styrene-acrylic resin fine particles A. As a method for preparing an aqueous dispersion of styrene-acrylic resin fine particles A, for example, the following method is preferably exemplified.

(1) In the case of a vinyl resin, a styrene-acrylic resin fine particle A is directly produced by a polymerization reaction selected from a suspension polymerization method, an emulsion polymerization method, a seed polymerization method and a dispersion polymerization method using a vinyl monomer as a starting material. A process for producing an aqueous dispersion of
(2) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, and epoxy resin, a precursor (monomer, oligomer, etc.) or a solvent solution thereof was dispersed in an aqueous medium in the presence of an appropriate dispersant. Then, the method of manufacturing the aqueous dispersion of the resin fine particle A by heating or adding a hardening | curing agent and making it harden | cure.
(3) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, epoxy resin, etc., a precursor (monomer, oligomer, etc.) or a solvent solution thereof (preferably liquid. It may be liquefied by heating). A method in which a suitable emulsifier is dissolved therein and then water is added to perform phase inversion emulsification.
(4) Resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) The styrene-acrylic resin fine particles A are obtained by pulverizing using, and then classified, and then dispersed in water in the presence of a suitable dispersant.
(5) A spray of a resin solution prepared by previously dissolving a resin prepared in a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent. To obtain styrene-acrylic resin fine particles A, and then to disperse the resin fine particles in water in the presence of an appropriate dispersant.
(6) A poor solvent is added to a resin solution in which a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is dissolved in a solvent. Or by cooling the resin solution previously heated and dissolved in a solvent to precipitate the styrene-acrylic resin fine particles A, and then removing the solvent to obtain resin fine particles. A method of dispersing in water in the presence of a dispersant.
(7) A resin solution prepared by previously dissolving a resin prepared by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent is appropriately dispersed. A method in which the solvent is removed by heating or decompression after being dispersed in an aqueous medium in the presence of an agent.
(8) A suitable emulsifier in a resin solution in which a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is dissolved in a solvent. After water is dissolved, water is added to perform phase inversion emulsification.

<Acrylic resin fine particles B>
The resin for the acrylic resin fine particles B is not particularly limited as long as it is a polymer that does not contain styrene and contains either an acrylic ester or a methacrylic ester, and a known resin is appropriately selected according to the purpose. However, it is preferably incompatible with the polyester resin forming the toner base particles and swells with respect to ethyl acetate. Moreover, it is preferable that it is resin which can form an aqueous dispersion in an aqueous medium. Examples of the resin for the acrylic resin fine particles B include acrylate polymer and methacrylic acid ester polymer.
The acrylic resin fine particles B are preferably fine particles of a crosslinked resin or an uncrosslinked resin containing at least one of an acrylic ester polymer and a methacrylic ester polymer.
The acrylic resin fine particles B are preferably incompatible with the polyester resin and swell with respect to an organic solvent (ethyl acetate).

  The acrylic resin fine particles B are white emulsions that are incompatible with the polyester resin, and the degree of swelling with respect to an organic solvent varies depending on the difference in crosslinking density. As a method for controlling the swellability, there are a crosslinking density and a constituent monomer. However, the constituent monomer may be changed in order to control physical properties other than the swellability of the acrylic resin fine particles.

  The acrylic resin fine particle B is preferably a cross-linked polymer in order to be fixed on the surface of the toner droplet without being dissolved when adhering to the emulsified droplet of the toner material described later, and at least two unsaturated Those copolymerized with a monomer having a group are preferred. The monomer having at least two unsaturated groups is not particularly limited and may be appropriately selected depending on the purpose. For example, a sodium salt of methacrylic acid ethylene oxide adduct sulfate (“Eleminol RS-30”) Manufactured by Sanyo Chemical Industries, Ltd.), divinyl compounds such as divinylbenzene, and diacrylate compounds such as 1,6-hexanediol acrylate.

If the acrylic resin fine particles B have a swelling property with respect to an organic solvent, not only can a stable transfer rate and a target upper and lower limit temperature be expected, but also a circularity of 0.950 to 0.975, and, profiled toner having excellent cleanability with a smooth surface texture of the order of a BET specific surface area of 0.5m ² /g~4.0m ² / g can be produced. However, if the degree of swelling is too large, the degree of circularity tends to be too low, and if the degree of swelling is too small, a toner having a large BET specific surface area and inferior transfer rate tends to be produced.

  When the degree of hydrophobicity of the acrylic resin microparticles B is less than 70%, the anti-aggregation performance may be deteriorated, and when it exceeds 90%, adhesion to the toner may be deteriorated and the hot offset resistance may be deteriorated. .

  There is no restriction | limiting in particular as an acid value of the said acrylic resin microparticles | fine-particles B, Although it can select suitably according to the objective, 0 mgKOH / g-15 mgKOH / g are preferable, and 5-15 mgKOH / g is especially preferable. When the acid value exceeds 15 mgKOH / g, the styrene-acrylic resin fine particle A layer is not formed well on the outermost surface of the toner base, so that dispersion stability during toner production cannot be obtained, Agglomeration may be reduced. On the other hand, when the acid value is in the particularly preferred range, it is advantageous in terms of toner manufacturability and toner anti-aggregation resistance.

The volume average particle size of the acrylic resin fine particles B is preferably 10 nm to 500 nm, and more preferably 10 nm to 52 nm, in terms of controlling the particle size and particle size distribution of the emulsified particles . When the volume average particle size is less than 10 nm, the spacer effect cannot be sufficiently obtained, so that the non-electrostatic adhesion force of the toner particles cannot be reduced. When the stress is large, the acrylic resin fine particles B and the external additive are easily buried in the toner surface, and there is a possibility that sufficient transfer efficiency cannot be maintained for a long time. When the volume average particle diameter exceeds 500 nm, the fluidity of the toner is deteriorated and the uniform transferability may be hindered.
On the other hand, when the volume average particle size is in the more preferable range, the non-electrostatic adhesion force of the toner particles can be reduced by the spacer effect, and the mechanical stress with time is large as in a high-speed machine. In this case, it is possible to suppress an increase in non-electrostatic adhesion due to the fine particles being embedded in the surface of the toner, and a sufficient transfer efficiency can be maintained over a long period of time. In particular, the toner produced by the production method of the present invention is very effective when it has a primary transfer step, a secondary transfer step, and a double transfer step in the intermediate transfer system. The effect can be exerted particularly greatly in a relatively high-speed image forming process (transfer linear speed: 100 mm / sec to 1,000 mm / sec, transfer time at the secondary nip portion: 0.5 msec to 60 msec). In a process with a lower linear speed and a shorter secondary transfer time than this, the difference between the present invention and a toner having no acrylic resin fine particles on the surface is not large. Further, when the speed is higher than this, the transfer efficiency tends to be prevented from being lowered.
The volume average particle size and particle size distribution of the acrylic resin fine particles B can be measured by the same method as that for the styrene-acrylic resin fine particles A.

As described above, in general, the toner filled in the developing machine has the resin particles on the toner surface embedded in the toner mainly due to mechanical stress inside the developing machine, or moves to the recesses on the surface of the toner particle main body. As a result, the effect of reducing the adhesion force is lost. Further, when the external additive is exposed to the same stress, it is buried inside the toner, and the adhesion force of the toner is increased.
However, the toner according to the production method of the present invention has a relatively large acrylic resin fine particle B which is difficult to be embedded in the toner base particle main body, and is relatively hard because it is crosslinked. In this case, the spacer effect is maintained without deformation, preventing the external additive from being buried and suitable for maintaining the above-mentioned adhesion.

The weight average molecular weight (Mw) of the acrylic resin fine particles B is preferably 10,000 to 2,000,000, and more preferably 300,000 to 450,000.
If the weight average molecular weight is less than 10,000, it tends to swell, and the degree of circularity tends to be too low. If it exceeds 2,000,000, it becomes difficult to swell, and the specific surface area becomes large. A toner with poor transfer may be produced. On the other hand, when the weight average molecular weight is in the more preferable range, it is advantageous in terms of toner circularity and transferability.

The glass transition temperature (Tg) of the acrylic resin fine particles B is preferably 40 ° C to 100 ° C, and more preferably 45 ° C to 80 ° C.
When the Tg is less than 40 ° C., sufficient heat storage stability in the storage temperature range of the toner cannot be obtained, and aggregation of the toner particles may occur. In some cases, the low-temperature fixability of the toner may be hindered.

  The addition amount of the acrylic resin fine particles B is preferably 0.5% by mass to 5% by mass and more preferably 1% by mass to 4% by mass with respect to the toner base particles. When the addition amount is less than 0.5% by mass, the non-electrostatic adhesion force of the toner particles may not be reduced because the spacer effect is not sufficiently obtained. There is a risk that the fluidity of the toner will deteriorate, the uniform transferability will be hindered, the fine particles will not be sufficiently fixed to the toner and will be easily detached, and will adhere to the carrier and the photoconductor, which will contaminate the photoconductor. is there.

  Moreover, it is preferable that the said acrylic resin microparticles | fine-particles B have a property which produces | generates an aggregate in the aqueous medium containing the said anionic surfactant. In the production method of the present invention, when the acrylic resin fine particles B are added to the aqueous medium before emulsification or the emulsified or dispersed liquid after emulsification in the emulsification step, the acrylic resin fine particles B adhere to the droplets of the toner material. It is not preferable to exist independently and stably. Since the acrylic resin fine particles B have the property of forming aggregates in the aqueous medium containing the anionic surfactant, the acrylic resin fine particles B present on the water phase side during or after emulsification are used as a liquid of the toner material. It moves to the droplet surface and can easily adhere to the droplet surface of the toner material. That is, in the aqueous medium containing the anionic surfactant, the acrylic resin fine particles B are unstable and usually aggregate, and if there is a toner material droplet, When the attractive force is strong, a complex of different particles is formed.

-Anionic surfactant-
Examples of the anionic surfactant used for preparing the acrylic resin fine particles B include fatty acid salts, alkyl sulfate esters, alkyl aryl sulfonates, alkyl diaryl ether disulfonates, dialkyl sulfosuccinates, alkyl phosphates, and naphthalenes. Examples include sulfonic acid formalin condensate, polyoxyethylene alkyl phosphate ester salt, and glyceryl borate fatty acid ester.

[Method for Preparing Acrylic Resin Fine Particle B]
As a method for adjusting the acrylic resin fine particles B, the same method as the method for adjusting the ethylene-acrylic resin fine particles A described above can be used.
As described above, it is preferable that the acrylic resin fine particles B have a property of generating aggregates in an aqueous medium containing an anionic surfactant because they easily adhere to the surface of the toner material droplets. The acrylic resin fine particles B having such properties are prepared by adjusting the acrylic resin fine particles B in the presence of a nonionic surfactant, an amphoteric surfactant, and a cationic surfactant. It can be prepared by using a resin into which a cationic group such as an amine group or an ammonium base is introduced.

-Cationic surfactant-
Examples of the cationic surfactant include amine salt type surfactants and quaternary ammonium salt type cationic surfactants. Examples of the amine salt type surfactant include alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazolines, and the like. Examples of the quaternary ammonium salt type cationic surfactant include alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride and the like. . Among the cationic surfactants of the quaternary ammonium salt type, aliphatic primary, secondary or tertiary amine acids having a fluoroalkyl group, perfluoroalkyl (6 to 10 carbon atoms) sulfonamidopropyltrimethylammonium salt, etc. Preferred are aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like.
Commercially available products of the cationic surfactant include, for example, Surflon S-121 (manufactured by Asahi Glass Co., Ltd.); Florard FC-135 (manufactured by Sumitomo 3M Co.); Unidyne DS-202 (manufactured by Daikin Industries, Ltd.), MegaFuck F-150 F-824 (manufactured by Dainippon Ink, Inc.); Xtop EF-132 (manufactured by Tochem Products);

-Nonionic surfactant-
Examples of the nonionic surfactant include fatty acid amide derivatives and polyhydric alcohol derivatives.

-Amphoteric surfactant-
Examples of the amphoteric surfactant include alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine, N-alkyl-N, N-dimethylammonium betaine and the like.

<Toner base particles>
The toner base particles include at least a polyester resin, and further, if necessary, a colorant, another binder resin, an adhesive base material (other binder resin), a release agent, a charge control agent, a magnetic agent. Contains other ingredients such as materials.

<< Polyester resin >>
The polyester resin is one or two or more polyols represented by the following general formula (1) and one or two or more polycarboxylic acids represented by the following general formula (2). It has become.
A- (OH) m ... General formula (1)
[Wherein, A represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, or an aromatic group or heterocyclic aromatic group which may have a substituent. m represents an integer of 2 to 4. ]
B- (COOH) n ... General formula (2)
[Wherein, B represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, or an aromatic group or heterocyclic aromatic group which may have a substituent. n represents an integer of 2 to 4. ]

-Polyol-
Examples of the polyol represented by the general formula (1) include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbitol, 1,2, 3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2- Tylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide Examples include adducts, hydrogenated bisphenol A, hydrogenated bisphenol A ethylene oxide adduct, hydrogenated bisphenol A propylene oxide adduct, and the like.

  Examples of the polycarboxylic acid represented by the general formula (2) include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, and sebacic acid. Azelaic acid, malonic acid, n-dodecenyl succinic acid, isooctyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid, Isooctyl succinic acid, 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5 -Hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxyl Bread, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, emporic trimer acid, cyclohexanedicarboxylic acid, cyclohexenedicarboxylic acid , Butanetetracarboxylic acid, diphenylsulfonetetracarboxylic acid, ethylene glycol bis (trimellitic acid), and the like.

There is no restriction | limiting in particular as an acid value of the said polyester resin, Although it can select suitably according to the objective, 10 mgKOH / g-50 mgKOH / g are preferable, and 15-40 mgKOH / g is more preferable. When the acid value is less than 10 mgKOH / g, the dispersion stabilizing effect during production may not be obtained, and when it exceeds 50 mgKOH / g, the environmental stability of the toner charging ability may be deteriorated. On the other hand, when the acid value is in the more preferable range, it is advantageous in terms of toner manufacturability and toner charging ability.
The toner acid value is preferably 0.5 to 40.0 (KOH mg / g). When the toner acid value exceeds 40.0 (KOHmg / g), the extension or crosslinking reaction of the modified polyester becomes insufficient, and the high temperature offset resistance is affected. When the toner acid value is less than 0.5 (KOHmg / g), This is because the dispersion stabilizing effect due to the base compound during production cannot be obtained, and the extension or crosslinking reaction of the modified polyester tends to proceed, resulting in a problem in production stability.

  There is no restriction | limiting in particular as the weight average molecular weight Mw of the said polyester resin, Although it can select suitably according to the objective, 1,000-200,000 are preferable and 4000-6000 are more preferable. When the weight average molecular weight is less than 1,000, the hot offset resistance may be lowered, and when it exceeds 200,000, the low-temperature fixing performance may be lowered. On the other hand, when the weight average molecular weight is in the more preferable range, it is advantageous in terms of low-temperature fixing and hot offset resistance.

The polyester resin is preferably incompatible with the styrene-acrylic resin fine particles A and the acrylic resin fine particles B. Particularly, the polyester resin has almost no compatibility when the acrylic resin fine particles B are fine particles of a crosslinked resin containing at least one of an acrylate polymer and a methacrylate polymer. In the emulsification process, which is one step of toner production, the organic resin is present in the droplets of the toner material when the acrylic resin particles B are added before or after emulsification, so the acrylic resin particles B adhere to the droplet surface. May dissolve after. When the binder resin constituting the toner is a polyester resin and the acrylic resin fine particles B are fine particles of a crosslinked resin containing at least one of an acrylate polymer and a methacrylate polymer, Since the solubility is low, the acrylic resin fine particles B are present in a state of adhering without being compatible with the droplets of the toner material. Accordingly, it is possible to achieve a desirable form in which the ink enters to some extent from the surface of the droplet and is adhered and fixed to the toner surface after the organic solvent is removed.
It is determined by the following method that the polyester resin is incompatible with the acrylic resin fine particles B. That is, when the polyester resin is dissolved at a ratio of 50% by mass with respect to the organic solvent, and various solutions are added to the solution, the case where the polyester resin is separated into two layers is incompatible and the case where the polyester resin is not separated is compatible Judging by visual inspection.

  There is no restriction | limiting in particular as glass transition temperature (Tg) of the said polyester resin, Although it can select suitably according to the objective, 10-80 degreeC is preferable, 30-70 degreeC is more preferable, 40-65 degreeC is preferable. Particularly preferred. When the glass transition temperature (Tg) is less than 10 ° C., the heat-resistant storage stability of the toner may deteriorate, and when it exceeds 80 ° C., the low-temperature fixability may not be sufficient. The toner of the present invention includes a layer composed of the resin fine particles A formed as the outermost layer on the surface of the toner base particles, and the resin fine particles B formed on the inner side of the layer. Good heat-resistant storage stability is exhibited even when the glass transition temperature is lower than that of the polyester toner.

<< Other ingredients >>
The other components contained in the toner base particles are not particularly limited and may be appropriately selected depending on the purpose. For example, colorants, other binder resins, adhesive base materials (other binder resins) ), Release agents, charge control agents, inorganic fine particles, fluidity improvers, cleaning property improvers, magnetic materials, and the like.

-Colorant-
The colorant is not particularly limited and may be appropriately selected from known dyes and pigments according to the purpose. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Lead Red, Lead Red, Cadmium Red, Cad Muum Mercury Red, Antimon Zhu, Permanent Red 4R, PA Red, Faise Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oh Lured, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Oxidation Chrome, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Ash Examples include degreen lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, and litbon. These may be used individually by 1 type and may use 2 or more types together.

  There is no restriction | limiting in particular as content in the said toner of the said coloring agent, Although it can select suitably according to the objective, 1 mass%-15 mass% are preferable, and 3 mass%-10 mass% are more preferable. When the content of the colorant is less than 1% by mass, a reduction in the coloring power of the toner is observed. When the content exceeds 15% by mass, poor dispersion of the pigment in the toner occurs, and the coloring power decreases. In some cases, the electrical characteristics of the toner may be degraded.

  The colorant may be used as a master batch combined with a master batch resin. The masterbatch resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, polyester, styrene or a substituted polymer thereof, a styrene copolymer, and polymethyl Methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic hydrocarbon resin , Alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the polymer of styrene or a substituted product thereof include polyester resin, polystyrene, poly p-chlorostyrene, and polyvinyl toluene. Examples of the styrene copolymer include a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene-vinylnaphthalene copolymer, and a styrene-methyl acrylate copolymer. Polymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene- Butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene N-acrylonitrile-indene copolymer, Styrene - maleic acid copolymer, styrene - like maleic acid ester copolymer.

  The masterbatch can be produced by mixing or kneading the masterbatch resin and the colorant under a high shear force. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the masterbatch resin. The so-called flushing method is also suitable in that the wet cake of the colorant can be used as it is, and it does not need to be dried. This flushing method is a method of mixing or kneading an aqueous paste containing water of the colorant together with the masterbatch resin and the organic solvent, and transferring the colorant to the resin side to remove moisture and organic solvent components. It is. For the mixing or kneading, for example, a high shear dispersion device such as a three-roll mill is preferably used. The colorant uses either the toner base particle or the acrylic resin fine particle B by utilizing the difference in affinity between the polyester resin forming the toner base particle and the resin forming the acrylic resin fine particle B with respect to the two resins. Can also be optionally included. It is well known that the colorant deteriorates the charging performance of the toner when present on the toner surface. Therefore, the toner charging performance (environmental stability, charge retention ability, charge amount, etc.) can be improved by selectively including the colorant in the toner base particles present in the inner layer.

-Other binder resins-
The binder resin used in the present invention may be a combination of the polyester resin and another binder resin. There is no restriction | limiting in particular as another binder resin combined with the said polyester resin, A well-known binder resin can be suitably selected according to the objective, For example, a silicone resin, a styrene-acryl resin, a styrene resin, an acrylic resin , Epoxy resin, diene resin, phenol resin, terpene resin, coumarin resin, amidoimide resin, butyral resin, urethane resin, ethylene-vinyl acetate resin, and the like.

-Adhesive substrate (other binder resins)-
The adhesive substrate is an adhesive polymer obtained by reacting an active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound in the aqueous medium. At least.

-Active hydrogen group-containing compound-
The active hydrogen group-containing compound acts as a crosslinking agent or elongation agent when a prepolymer capable of reacting with the active hydrogen group-containing compound undergoes a crosslinking or elongation reaction in the aqueous medium.
The active hydrogen group-containing compound is not particularly limited as long as it has an active hydrogen group, and can be appropriately selected according to the purpose. For example, a prepolymer capable of reacting with the active hydrogen group-containing compound is an isocyanate. In the case of the group-containing polyester prepolymer (A), amines (B) are preferable in that they can have a high molecular weight by a reaction such as an elongation reaction or a crosslinking reaction with the isocyanate group-containing polyester prepolymer (A). is there.
There is no restriction | limiting in particular as said active hydrogen group, According to the objective, it can select suitably, For example, a hydroxyl group (alcoholic hydroxyl group thru | or phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.

  By including the active hydrogen group-containing compound and the modified polyester resin capable of reacting with the active hydrogen group-containing compound in the toner material of the present invention, the mechanical strength of the resulting toner is increased, and the acrylic resin fine particles B and external additives are added. The burial of the agent can be suppressed. When the active hydrogen group-containing compound has a cationic polarity, the acrylic resin fine particles B can be attracted electrostatically. Further, the fluidity of the toner during heat fixing can be adjusted, and the fixing temperature range can be widened. The polymer capable of reacting with the active hydrogen group-containing compound can be said to be a binder resin precursor (prepolymer).

The amines (B) are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include diamine (B1), trivalent or higher polyamine (B2), amino alcohol (B3), and amino mercaptan. (B4), amino acid (B5), and those obtained by blocking the amino groups of B1 to B5 (B6).
These may be used individually by 1 type and may use 2 or more types together. Among these, diamine (B1) alone or a mixture of diamine (B1) and a small amount of trivalent or higher polyamine (B2) is particularly preferable.

Examples of the diamine (B1) include aromatic diamines, alicyclic diamines, and aliphatic diamines. Examples of the aromatic diamine include phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, and the like. Examples of the alicyclic diamine include 4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, and isophoronediamine. Examples of the aliphatic diamine include ethylene diamine, tetramethylene diamine, and hexamethylene diamine.
Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine.
Examples of the amino alcohol (B3) include ethanolamine and hydroxyethylaniline.
Examples of the amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
Examples of the blocked B1-B5 amino group (B6) include, for example, ketimine compounds and oxazolidone compounds obtained from any of the amines of B1-B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) Etc.

--Polymer capable of reacting with active hydrogen group-containing compound--
The polymer capable of reacting with the active hydrogen group-containing compound (hereinafter sometimes referred to as “prepolymer”) is not particularly limited as long as it has at least a site capable of reacting with the active hydrogen group-containing compound. However, it can be appropriately selected from known resins, and examples thereof include polyol resins, polyacrylic resins, polyester resins, epoxy resins, and derivative resins thereof. These may be used individually by 1 type and may use 2 or more types together. Among these, a polyester resin is particularly preferable in terms of high fluidity and transparency during melting.

The site capable of reacting with the active hydrogen group-containing compound in the prepolymer is not particularly limited and may be appropriately selected from known substituents. For example, an isocyanate group, an epoxy group, a carboxylic acid, An acid chloride group etc. are mentioned. These may be contained singly or in combination of two or more. Among these, an isocyanate group is particularly preferable.
Among prepolymers, it is easy to adjust the molecular weight of the polymer component, and oil-less low-temperature fixing characteristics in dry toners, in particular, good releasability and fixability even in the absence of a release oil application mechanism to a fixing heating medium. A urea bond-forming group-containing polyester resin (RMPE) is particularly preferable because it can be secured.
As a urea bond production | generation group, an isocyanate group etc. are mentioned, for example. When the urea bond-forming group in the urea bond-forming group-containing polyester resin (RMPE) is the isocyanate group, an isocyanate group-containing polyester prepolymer (A) is particularly suitable as the polyester resin (RMPE).

  The isocyanate group-containing polyester prepolymer (A) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is a polycondensate of a polyol (PO) and a polycarboxylic acid (PC), And what made the said active hydrogen group containing polyester resin react with polyisocyanate (PIC) etc. are mentioned.

  There is no restriction | limiting in particular as said polyol (PO), According to the objective, it can select suitably, For example, diol (DIO), trihydric or more polyol (TO), diol (DIO), and trihydric or more polyol And a mixture with (TO). These may be used individually by 1 type and may use 2 or more types together. Among these, the diol (DIO) alone or a mixture of the diol (DIO) and a small amount of the trivalent or higher polyol (TO) is preferable.

There is no restriction | limiting in particular as said diol (DIO), According to the objective, it can select suitably, For example, alkylene glycol, alkylene ether glycol, alicyclic diol, the alkylene oxide adduct of alicyclic diol, bisphenols And alkylene oxide adducts of bisphenols.
The alkylene glycol is preferably one having 2 to 12 carbon atoms, such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, and the like. Can be mentioned. Examples of the alkylene ether glycol include diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. Examples of the alicyclic diol include 1,4-cyclohexanedimethanol and hydrogenated bisphenol A. Examples of the alkylene oxide adduct of the alicyclic diol include those obtained by adding an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide to the alicyclic diol. Examples of the bisphenols include bisphenol A, bisphenol F, and bisphenol S. Examples of the alkylene oxide adduct of the bisphenol include those obtained by adding an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide to the bisphenol.
Among these, alkylene glycols having 2 to 12 carbon atoms, alkylene oxide adducts of bisphenols, and the like are more preferable, alkylene oxide adducts of bisphenols, alkylene oxide adducts of bisphenols, The mixture of is particularly preferred.

The trihydric or higher polyol (TO) is preferably a trihydric to octahydric or higher polyol, for example, a trihydric or higher polyhydric aliphatic alcohol, a trihydric or higher polyphenol, or a trihydric or higher polyphenol. And alkylene oxide adducts.
Examples of the trihydric or higher polyhydric aliphatic alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, and the like. Examples of the trihydric or higher polyphenols include trisphenol PA, phenol novolak, cresol novolak, and the like. Examples of the alkylene oxide adduct of the trihydric or higher polyphenol include those obtained by adding an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide to the trihydric or higher polyphenol.

  The mixing mass ratio (DIO: TO) of the diol (DIO) and the trivalent or higher polyol (TO) in the mixture of the diol (DIO) and the trivalent or higher polyol (TO) is 100: 0. .01 to 10 is preferable, and 100: 0.01 to 1 is more preferable.

There is no restriction | limiting in particular as said polycarboxylic acid (PC), According to the objective, it can select suitably, For example, dicarboxylic acid (DIC), trivalent or more polycarboxylic acid (TC), dicarboxylic acid (DIC) And a mixture of trivalent or higher polycarboxylic acids.
These may be used individually by 1 type and may use 2 or more types together. Among these, dicarboxylic acid (DIC) alone or a mixture of DIC and a small amount of trivalent or higher polycarboxylic acid (TC) is preferable.

Examples of the dicarboxylic acid (DIC) include alkylene dicarboxylic acid, alkenylene dicarboxylic acid, and aromatic dicarboxylic acid.
Examples of the alkylene dicarboxylic acid include succinic acid, adipic acid, and sebacic acid. As said alkenylene dicarboxylic acid, a C4-C20 thing is preferable, For example, a maleic acid, a fumaric acid, etc. are mentioned. As said aromatic dicarboxylic acid, a C8-C20 thing is preferable, For example, a phthalic acid, an isophthalic acid, a terephthalic acid, naphthalene dicarboxylic acid etc. are mentioned.
Among these, alkenylene dicarboxylic acid having 4 to 20 carbon atoms and aromatic dicarboxylic acid having 8 to 20 carbon atoms are preferable.

The trivalent or higher polycarboxylic acid (TC) is preferably a trivalent to octavalent or higher one, and examples thereof include aromatic polycarboxylic acids.
The aromatic polycarboxylic acid preferably has 9 to 20 carbon atoms, and examples thereof include trimellitic acid and pyromellitic acid.

  As the polycarboxylic acid (PC), the dicarboxylic acid (DIC), the trivalent or higher polycarboxylic acid (TC), and a mixture of the dicarboxylic acid (DIC) and the trivalent or higher polycarboxylic acid, Any acid anhydride or lower alkyl ester selected from can also be used. Examples of the lower alkyl ester include methyl ester, ethyl ester, isopropyl ester and the like.

  Mixing mass ratio (DIC: TC) of the dicarboxylic acid (DIC) and the trivalent or higher polycarboxylic acid (TC) in the mixture of the dicarboxylic acid (DIC) and the trivalent or higher polycarboxylic acid (TC) There is no restriction | limiting in particular, According to the objective, it can select suitably, For example, 100: 0.01-10 are preferable and 100: 0.01-1 are more preferable.

  The mixing ratio for the polycondensation reaction between the polyol (PO) and the polycarboxylic acid (PC) is not particularly limited and may be appropriately selected depending on the intended purpose. The hydroxyl group in the polyol (PO) [ OH] and the equivalent ratio ([OH] / [COOH]) of the carboxyl group [COOH] in the polycarboxylic acid (PC) are preferably 2/1 to 1/1, and 1.5 / 1 to 1 / 1 is more preferable, and 1.3 / 1 to 1.02 / 1 is particularly preferable.

  There is no restriction | limiting in particular as content in the said isocyanate group containing polyester prepolymer (A) of the said polyol (PO), Although it can select suitably according to the objective, For example, 0.5 mass%-40 mass% Is preferable, 1% by mass to 30% by mass is more preferable, and 2% by mass to 20% by mass is particularly preferable. When the content is less than 0.5% by mass, the hot offset resistance deteriorates, and it may be difficult to achieve both the heat-resistant storage stability and the low-temperature fixability of the toner, and exceeds 40% by mass. In some cases, the low-temperature fixability may deteriorate.

There is no restriction | limiting in particular as said polyisocyanate (PIC), According to the objective, it can select suitably, For example, aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic diisocyanate, araliphatic diisocyanate, isocyanurates And those polyisocyanates blocked with phenol derivatives, oximes, caprolactams, and the like.
Examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, Examples include tetramethylhexane diisocyanate. Examples of the alicyclic polyisocyanate include isophorone diisocyanate and cyclohexylmethane diisocyanate. Examples of the aromatic diisocyanate include tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, diphenylene-4,4′-diisocyanate, 4,4′-diisocyanato-3,3′-dimethyldiphenyl, 3- Examples thereof include methyldiphenylmethane-4,4′-diisocyanate and diphenyl ether-4,4′-diisocyanate. Examples of the araliphatic diisocyanate include α, α, α ′, α′-tetramethylxylylene diisocyanate. Examples of the isocyanurates include tris-isocyanatoalkyl isocyanurate and triisocyanatocycloalkyl-isocyanurate. These can be used alone or in combination of two or more.

As a mixing ratio when the polyisocyanate (PIC) and the active hydrogen group-containing polyester resin (for example, a hydroxyl group-containing polyester resin) are reacted, the isocyanate group [NCO] in the polyisocyanate (PIC) and the hydroxyl group-containing component are used. The mixing equivalent ratio ([NCO] / [OH]) with the hydroxyl group [OH] in the polyester resin is preferably 5/1 to 1/1, more preferably 4/1 to 1.2 / 1, and 3/1 to 1.5 / 1 is particularly preferred.
When the isocyanate group [NCO] exceeds 5, low-temperature fixability may be deteriorated, and when it is less than 1, offset resistance may be deteriorated.

There is no restriction | limiting in particular as content in the said isocyanate group containing polyester prepolymer (A) of the said polyisocyanate (PIC), Although it can select suitably according to the objective, 0.5 mass%-40 mass% are Preferably, 1% by mass to 30% by mass is more preferable, and 2% by mass to 20% by mass is particularly preferable.
When the content is less than 0.5% by mass, the hot offset resistance is deteriorated, and it may be difficult to achieve both heat-resistant storage stability and low-temperature fixability. When the content exceeds 40% by mass, Low temperature fixability may deteriorate.

The average number of isocyanate groups contained in one molecule of the isocyanate group-containing polyester prepolymer (A) is preferably 1 or more, more preferably 1.2 to 5, and particularly preferably 1.5 to 4.
When the average number of the isocyanate groups is less than 1, the molecular weight of the polyester resin (RMPE) modified with the urea bond-forming group is lowered, and the hot offset resistance may be deteriorated.

  The weight average molecular weight (Mw) of the polymer capable of reacting with the active hydrogen group-containing compound is 3,000 to 40,000 in terms of molecular weight distribution by GPC (gel permeation chromatography) soluble in tetrahydrofuran (THF). Preferably, 4,000 to 30,000 is more preferable. When the weight average molecular weight (Mw) is less than 3,000, the heat resistant storage stability may be deteriorated, and when it exceeds 40,000, the low temperature fixability may be deteriorated.

If necessary, a reaction terminator can be used to stop the crosslinking or extension reaction between the active hydrogen group-containing compound and the polymer capable of reacting with the active hydrogen group-containing compound. Use of the reaction terminator is preferable in that the molecular weight and the like of the adhesive substrate can be controlled within a desired range.
Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.) or those obtained by blocking these (ketimine compounds).

As a mixing ratio of the amines (B) and the isocyanate group-containing polyester prepolymer (A), the isocyanate group [NCO] in the isocyanate group-containing prepolymer (A) and the amines (B) As the mixing equivalent ratio ([NCO] / [NHx]) of the amino group [NHx], 1/3 to 3/1 is preferable, 1/2 to 2/1 is more preferable, and 1 / 1.5-1 to 1. 5/1 is particularly preferred.
If the mixing equivalent ratio ([NCO] / [NHx]) is less than 1/3, the low-temperature fixability may decrease. If it exceeds 3/1, the molecular weight of the urea-modified polyester resin will be low. The hot offset resistance may be deteriorated.

  The weight average molecular weight (Mw) of the adhesive substrate (other binder resin) is not particularly limited and may be appropriately selected depending on the intended purpose. The molecular weight distribution by permeation chromatography) is preferably 3,000 or more, more preferably 5,000 to 1,000,000, and particularly preferably 7,000 to 500,000. When the weight average molecular weight is less than 3,000, the hot offset resistance may be deteriorated.

The molecular weight distribution can be measured by gel permeation chromatography (GPC), for example, as follows. That is, first, the column is stabilized in a 40 ° C. heat chamber, and at this temperature, tetrahydrofuran (THF) as a column solvent is allowed to flow at a flow rate of 1 ml / min. Measurement is performed by injecting 50 μl to 200 μl of a tetrahydrofuran sample solution of the prepared resin. In measuring the molecular weight of the sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of the calibration curve prepared by several monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, Pressure Chemical Co. Alternatively, Toyo Soda Kogyo Co., Ltd. has a molecular weight of 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8. It is preferable to use 6 × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. An RI (refractive index) detector can be used as the detector.

-Release agent-
There is no restriction | limiting in particular as said mold release agent, Although it can select suitably according to the objective, Melting | fusing point has a low melting point mold release agent of 50 to 120 degreeC. The low melting point release agent, when dispersed with the binder resin, effectively acts as a release agent between the fixing roller and the toner interface. The hot offset property is good even when the mold is not applied.

  Preferable examples of the mold release agent include waxes and waxes. Examples of waxes and waxes include natural wax and synthetic wax. Examples of the natural wax include plant waxes such as carnauba wax, cotton wax, wood wax, and rice wax; animal waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cercin; paraffin, microcrystalline, petrolatum, and the like. Examples include petroleum wax. Examples of the synthetic wax include synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax; synthetic waxes such as esters, ketones and ethers. Also, fatty acid amides such as 12-hydroxystearic amide, stearic amide, phthalic anhydride imide, chlorinated hydrocarbons; low molecular weight crystalline polymer resins, poly-n-stearyl methacrylate, poly-n-lauryl A homopolymer or copolymer of a polyacrylate such as methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate); a crystalline polymer having a long alkyl group in the side chain may be used. These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular as melting | fusing point of the said mold release agent, Although it can select suitably according to the objective, 50 to 120 degreeC is preferable and 60 to 90 degreeC is more preferable. When the melting point is less than 50 ° C., the release agent may adversely affect the heat resistant storage stability. When the melting point exceeds 120 ° C., a cold offset may easily occur during fixing at a low temperature. The melt viscosity of the release agent is preferably 5 cps to 1,000 cps, more preferably 10 cps to 100 cps, as a measured value at a temperature 20 ° C. higher than the melting point of the release agent. If the melt viscosity is less than 5 cps, the releasability may be lowered, and if it exceeds 1,000 cps, the effect of improving hot offset resistance and low-temperature fixability may not be obtained. There is no restriction | limiting in particular as content in the said toner base particle of the said mold release agent, Although it can select suitably according to the objective, 0 mass%-40 mass% are preferable, and 3 mass%-30 mass% are preferable. More preferred. When the content exceeds 40% by mass, the fluidity of the toner may be deteriorated.

  The release agent uses a difference in affinity for the three resins of the polyester resin, the resin for the acrylic resin fine particles B, and the resin for the styrene-acrylic resin fine particles A in the toner base particles, Any of polyester resin (first resin phase) in the particle body, resin for acrylic resin fine particles B (second resin phase), and resin for styrene-acrylic resin fine particles A (third resin phase) It can be arbitrarily contained. By selectively including in the resin phase of the acrylic resin fine particles B present in the toner outer layer, the release of the release agent occurs sufficiently even in a short heating time at the time of fixing, so that sufficient release properties can be obtained. . Further, by selectively containing the release agent in the first resin phase in the toner base particles existing in the inner layer, the spent of the release agent to other members such as a photoreceptor and a carrier is suppressed. be able to. In the present invention, the arrangement of the release agent may be designed relatively freely, and any arrangement may be taken according to each image forming process.

-Charge control agent-
The charge control agent is not particularly limited and may be appropriately selected from known ones according to the purpose. Examples thereof include nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, and molybdate chelate pigments. , Rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus alone or compounds thereof, tungsten alone or compounds thereof, fluorine activators, salicylic acid metal salts And metal salts of salicylic acid derivatives. These may be used individually by 1 type and may use 2 or more types together.

  Commercially available products may be used as the charge control agent. Examples of the commercially available products include bontron 03 of a nigrosine dye, bontron P-51 of a quaternary ammonium salt, and bontron S-34 of a metal-containing azo dye. , Oxynaphthoic acid metal complex E-82, salicylic acid metal complex E-84, phenolic condensate E-89 (above, manufactured by Orient Chemical Industries), quaternary ammonium salt molybdenum complex TP-302 TP-415 (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (Above, manufactured by Hoechst), LRA-901, LR-147 (Japan (Manufactured by Carlit Co., Ltd.), copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymer compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts.

  The charge control agent utilizes the difference in affinity of the polyester resin in the toner base particles with respect to the resin for the acrylic resin fine particles B or the resin for the styrene-acrylic resin fine particles A. The resin phase in the resin, the resin phase of the acrylic resin fine particles B, and the resin phase of the styrene-acrylic resin fine particles A can be arbitrarily contained. By selectively including it in the resin phase of the acrylic resin fine particles B present on the toner surface, it becomes easier to obtain an effect against power failure with a smaller amount of the charge control agent. Further, by selectively containing the charge control agent in the resin phase in the toner base particles existing in the inner layer, the spent of the charge control agent on other members such as a photoreceptor and a carrier can be suppressed. In the toner manufacturing method of the present invention, the arrangement of the charge control agent may be designed relatively freely, and an arbitrary arrangement may be taken according to each image forming process.

  The content of the charge control agent varies depending on the type of the resin, the presence or absence of an additive, a dispersion method, and the like, and cannot be generally specified. % By mass is preferable, and 0.2% by mass to 5% by mass is more preferable. If the content of the charge control agent is less than 0.1% by mass, the charge controllability may not be obtained. If the content exceeds 10% by mass, the chargeability of the toner becomes too large, and the main charge control agent In other words, the electrostatic attraction force with the developing roller is increased, and the fluidity of the developer and the image density may be reduced.

-Magnetic material-
There is no restriction | limiting in particular as said magnetic material, According to the objective, it can select suitably from well-known things, For example, iron powder, a magnetite, a ferrite etc. are mentioned. Among these, white is preferable in terms of color tone.

<Other ingredients>
Other components contained in the toner of the present invention include inorganic fine particles, fluidity improvers, external additives such as cleaning improvers, and the like.
-Inorganic fine particles-
The inorganic fine particles are used as an external additive for imparting fluidity, developability, chargeability and the like to toner particles. The inorganic fine particles are not particularly limited and may be appropriately selected from known ones according to the purpose. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, titanate Strontium, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, carbonized Silicon, silicon nitride, or the like can be used. These may be used individually by 1 type and may use 2 or more types together.

As the inorganic fine particles for assisting the fluidity, developability and chargeability of the toner base particles obtained in the present invention, in addition to the inorganic fine particles having a primary volume average particle size of 80 nm to 500 nm, Inorganic fine particles having a small particle diameter can be preferably used. In particular, hydrophobic silica, hydrophobic titanium oxide and the like are preferable. The primary volume average particle size of the inorganic fine particles is preferably 5 nm to 50 nm, and more preferably 10 nm to 30 nm. As the specific surface area by the BET ^method, 20m ² / ^g~500m 2 / g are preferred. The use ratio of the inorganic fine particles is preferably 0.01% by mass to 5% by mass and more preferably 0.01% by mass to 2.0% by mass with respect to the toner having a large particle size and a small particle size, respectively.

-Fluidity improver-
The fluidity improver is an agent that performs surface treatment to increase hydrophobicity and prevents deterioration of flow characteristics and charging characteristics even under high humidity. For example, a silane coupling agent, a silylating agent, Examples thereof include a silane coupling agent having a fluoroalkyl group, an organic titanate coupling agent, an aluminum coupling agent, silicone oil, and modified silicone oil. It is particularly preferable that the silica and the titanium oxide are surface-treated with such a fluidity improver and used as hydrophobic silica and hydrophobic titanium oxide.

-Cleaning improver-
The cleaning property improving agent is an agent added to the toner in order to remove the developer after transfer remaining on the photoreceptor or the primary transfer medium. For example, zinc stearate, calcium stearate, stearic acid, etc. Fatty acid metal salts; polymer fine particles produced by soap-free emulsion polymerization such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and the volume average particle size is preferably 0.01 μm to 1 μm.

  There is no restriction | limiting in particular as a weight average particle diameter of the toner of this invention, Although it can select suitably according to the objective, 1 micrometer-6 micrometers are preferable, and 2 micrometers-5 micrometers are more preferable. If the weight average particle size is less than 1 μm, toner dust is likely to occur in primary transfer and secondary transfer. Conversely, if the weight average particle size exceeds 6 μm, dot reproducibility becomes insufficient, and the graininess of the halftone part also deteriorates. As a result, a high-definition image cannot be obtained.

  The average circularity of the toner of the present invention is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.950 to 0.990. If the average circularity is less than 0.950, image uniformity during development deteriorates, toner transfer efficiency from the electrophotographic photosensitive member to the intermediate transfer member, or toner transfer from the intermediate transfer member to the recording material Efficiency may be reduced and uniform transfer may not be obtained. Further, since the toner of the present invention is produced by emulsification in an aqueous medium, it is particularly effective for reducing the particle size of color toners and obtaining an average circularity in the above range. .

<Average circularity>
The average circularity of the toner is defined by the following formula (2).
Average circularity SR =
(Perimeter length of a circle having the same area as the particle projection area / perimeter length of the particle projection image) × 100%
... Formula (2)
The average circularity of the toner is measured using a flow type particle image analyzer (“FPIA-3000”; manufactured by Sysmex Corporation), and analyzed using analysis software (FPIA-3000 FLOW PARTIC IMAGE ANALYZER version 00-11). be able to.
Specifically, 0.1% to 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate Neogen SC-A; manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a 100 ml glass beaker, and 0.1 g of each toner is added. Add ~ 0.5g, stir with microspatel, then add 80ml of ion-exchanged water. The obtained dispersion is subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner are measured using the FPIA-2100 until the concentration of the dispersion reaches 5,000 / μl to 15,000 / μl. In this measurement method, it is important that the concentration of the dispersion is 5,000 / μl to 15,000 / μl from the viewpoint of measurement reproducibility of the average circularity. In order to obtain the dispersion concentration, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the measurement of the toner particle diameter described above. If it is added in a large amount, noise due to bubbles is generated, and if it is too small, the toner cannot be sufficiently wetted. It will be enough. Further, the amount of toner added differs from the particle size, and is small for small particles and needs to be increased for large particles. When the toner particle size is 3 μm to 7 μm, the toner amount is 0.1 g to 0 g. By adding 0.5 g, the concentration of the dispersion can be adjusted to 5,000 / μl to 15,000 / μl.

The ratio (Dw / Dn) of the weight average particle diameter (Dw) to the number average particle diameter (Dn) in the toner of the present invention is not particularly limited and can be appropriately selected according to the purpose. 30 or less is preferable, and 1.00-1.30 is more preferable. When the ratio (Dw / Dn) is less than 1.00, in the case of a two-component developer, the toner is fused to the surface of the carrier during long-term agitation in the developing device, and the chargeability of the carrier is reduced. It tends to lead to deterioration. In the case of a one-component developer, toner filming on the developing roller and toner fusion to a member such as a blade are likely to occur because the toner is thinned. When the ratio (Dw / Dn) exceeds 1.30, it becomes difficult to obtain a high-resolution and high-quality image, and the toner particle size when the balance of the toner in the developer is performed. Fluctuations may increase.
On the other hand, when the ratio (Dw / Dn) is 1.00 to 1.30, the toner is easily excellent in all of heat resistance stability, low-temperature fixability, and hot offset resistance. In particular, when used in a full-color copying machine, the glossiness of the image is excellent. When used as a two-component developer, even if the developer is operated for a long period of time, there is little fluctuation in the toner particle diameter in the developer, and good and stable developability can be obtained even with long-term stirring in the developing device. In the case of using as a one-component developer, the fluctuation of the toner particle diameter is reduced even when the developer is operated, and the filming of the toner on the developing roller and a member for a blade or the like for thinning the toner No toner is fused to the toner, and good and stable developability can be obtained even when the developing device is used (stirred) for a long period of time, so that a high-quality image can be obtained.

<Weight average particle diameter (Dw), volume average particle diameter (Dv), and number average particle diameter (Dn)>
The weight average particle diameter (Dw), volume average particle diameter (Dv), and number average particle diameter (Dn) of the toner are measured using a particle size measuring device (“Multisizer III” manufactured by Beckman Coulter, Inc.) with an aperture diameter of 100 μm. It can be measured by measuring and analyzing with analysis software (Beckman Coulter Multisizer 3 Version 3.51).
Specifically, 0.5 ml of 10% by mass surfactant (alkylbenzene sulfonate, Neogen SC-A; manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a 100 ml beaker made of glass, and 0.5 g of each toner is added. Stir with a spatula and then add 80 ml of ion-exchanged water. The obtained dispersion is subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion is measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter) as the measurement solution. In the measurement, the toner sample dispersion is dropped so that the concentration indicated by the apparatus is 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of measurement reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

The BET specific surface area of the present invention the toner is not particularly limited and may be appropriately selected depending on the intended ^purpose, preferably ^{0.5m 2 /g~4.0m 2 / g, 0.5m} 2 / g~ 2.0 m ² / g is more preferable. When the BET specific surface area is less than 0.5 m ² / g, the entire toner surface is covered tightly, and the styrene-acrylic resin fine particles A have an adhesive property between the polyester resin component of the toner base particles and the fixing paper. In some cases, the fixing lower limit temperature may be increased, and the styrene-acrylic resin fine particles A may inhibit the exudation of the wax, so that the effect of releasing the wax may not be obtained and an offset may occur. When the BET specific surface area exceeds 4.0 m ² / g, the organic fine particles remaining on the toner surface largely protrude as convex portions, or the styrene-acrylic resin fine particles A remain as a coarse multi-layer. -Acrylic resin fine particles A inhibit the adhesion between the polyester resin component in the toner and the fixing paper, and an increase in the minimum fixing temperature is observed. Further, the styrene-acrylic resin fine particles A inhibit the exudation of the wax, the wax releasing effect cannot be obtained, and the occurrence of offset is observed. Further, the additive is raised, and the image quality is likely to be affected by the unevenness of the surface.

<BET specific surface area of toner>
The BET specific surface area of the toner can be measured using an automatic specific surface area / pore distribution measuring device TriStar 3000 (manufactured by Shimadzu Corporation).
Specifically, 1 g of toner is put in a dedicated cell, and degassing processing in the dedicated cell is performed using TriStar degassing dedicated unit, Bacuprep 061 (manufactured by Shimadzu Corporation). The deaeration treatment is performed at room temperature, and is performed for 20 hours under a reduced pressure condition of at least 13.33 Pa (100 mtorr) or less. The dedicated cell that has been deaerated can automatically obtain the BET specific surface area using TriStar 3000. Note that a nitrogen gas can be used as the adsorption gas.

(Toner production method)
The method for producing a toner for developing an electrostatic image according to the present invention includes at least the following steps a to c, and further includes other steps such as a washing step, a heating step, and a drying classification step, which are appropriately selected as necessary.
Step a: A toner material containing at least the polyester resin is dissolved or dispersed in an organic solvent to prepare a toner material dissolved or dispersed step Step b: The toner material dissolved or dispersed at least the styrene-acrylic resin Step c of adding and emulsifying or dispersing in an aqueous medium containing the fine particles A to prepare an emulsified or dispersed liquid: Step of preparing toner particles by removing an organic solvent from the emulsified or dispersed liquid. Resin fine particles B are added to either the aqueous medium or the emulsified or dispersed liquid.
The degree of hydrophobicity of the styrene-acrylic resin fine particles A needs to satisfy 60 to 80, and the degree of hydrophobicity of the acrylic resin fine particles B needs to satisfy 70 to 90.
Preferably, the volume average particle diameter of the styrene-acrylic resin fine particles A is smaller than the volume average particle diameter of the acrylic resin fine particles B, and the Tg and acid value of the styrene-acrylic resin fine particles A and acrylic resin fine particles B. , Volume average particle size, weight average molecular weight, and Tg, acid value, weight average molecular weight, etc. of the polyester resin are the same as those described above.
Hereinafter, the method for producing the toner of the present invention will be specifically described.

<Step a>
The step a is a step in which a toner material containing at least the polyester resin is dissolved or dispersed in an organic solvent to prepare a toner material dissolved or dispersed liquid.

<< Solution or Dispersion of Toner Material >>
The solution or dispersion of the toner material is prepared by dissolving or dispersing the toner material in an organic solvent.
The toner material comprises at least the polyester resin, and if necessary, the colorant, the active hydrogen group-containing compound, a polymer (prepolymer) capable of reacting with the active hydrogen group-containing compound, and the release agent. Agent, the charge control agent, and other components such as the magnetic material. The polyester resin used as the toner material in the step a and other components are not particularly limited as long as the toner can be formed, and can be appropriately selected according to the purpose. The above-described toner base particles described above Polyester resins and those listed above for the other components can be used.

The toner material is dissolved or dispersed in an organic solvent by mixing the polyester resin, the active hydrogen group-containing compound, the polymer capable of reacting with the active hydrogen group-containing compound, the release agent, the colorant, It can be carried out by dissolving or dispersing a toner material such as the charge control agent.
Further, in the toner material, components other than the polymer (prepolymer) capable of reacting with the active hydrogen group-containing compound may be added and mixed in the aqueous medium in the preparation of the aqueous medium in step b described later. Alternatively, the toner material dissolved or dispersed liquid may be added to the aqueous medium together with the toner material dissolved or dispersed liquid.

  The toner material preferably includes the active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound as a binder resin precursor, and the polymer capable of reacting with the active hydrogen group-containing compound includes: More preferred is a modified polyester resin. Since the active hydrogen group-containing compound and the polymer capable of reacting with the active hydrogen group-containing compound are contained in the droplets of the toner material, the mechanical strength of the obtained toner is increased, and the resin fine particles B and external additives are increased. Can be suppressed. When the active hydrogen group-containing compound has a cationic polarity, the resin fine particles B can be attracted electrostatically. Further, the fluidity of the toner during heat fixing can be adjusted, and the fixing temperature range can be widened.

-Organic solvent-
The organic solvent is not particularly limited as long as it is a solvent that can dissolve or disperse the toner material, and can be appropriately selected according to the purpose. However, it is easy to remove the toner material during granulation or after granulation. In this respect, those having a boiling point of less than 150 ° C. are preferred. Examples of such organic solvents include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, Examples include ethyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. Among these, ester solvents are preferable, and ethyl acetate is particularly preferable. These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular as the usage-amount of the said organic solvent, Although it can select suitably according to the objective, 40 mass parts-300 mass parts are preferable with respect to 100 mass parts of toner materials, and 60 mass parts-140 mass parts. Part is more preferable, and 80 parts by mass to 120 parts by mass is particularly preferable.

<Process b>
The step b is a step of preparing an emulsified or dispersed liquid by adding the emulsified or dispersed liquid of the toner material into an aqueous medium containing at least the styrene-acrylic resin fine particles A.
As the styrene-acrylic resin fine particles A used in the step b, the above-mentioned styrene-acrylic resin fine particles A described in the toner of the present invention can be used.

-Aqueous medium-
There is no restriction | limiting in particular as said aqueous medium, It can select suitably from well-known things, For example, water, a solvent miscible with water, a mixture thereof, etc. can be used. Among these, water is particularly preferable.
The solvent miscible with water is not particularly limited as long as it is miscible with water, and can be appropriately selected according to the purpose. Examples thereof include alcohol, dimethylformamide, tetrahydrofuran, cellosolves, and lower ketones. Can be used. Examples of the alcohol include methanol, isopropanol, and ethylene glycol. Examples of the lower ketones include acetone and methyl ethyl ketone. These may be used individually by 1 type and may use 2 or more types together.

The aqueous medium is preferably prepared by dispersing the styrene-acrylic resin fine particles A in an aqueous medium in the presence of an anionic surfactant. The addition amount of the anionic surfactant and the styrene-acrylic resin fine particles A in the aqueous medium is not particularly limited and may be appropriately selected depending on the intended purpose. Mass% is preferred.
The acrylic resin fine particles B may then be added to an aqueous medium, or may be added to an emulsified or dispersed liquid after emulsification described later. When the acrylic resin fine particles B are cohesive in an aqueous medium containing the anionic surfactant, the aqueous medium added with the acrylic resin fine particles B should be dispersed with a high-speed shearing disperser before emulsification. Is preferred.

-Anionic surfactant-
Examples of the anionic surfactant used for the preparation of the aqueous medium include alkylbenzene sulfonate, α-olefin sulfonate, phosphate ester, and anionic surfactant having a fluoroalkyl group. Among these, an anionic surfactant having a fluoroalkyl group is preferable.
Examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms or a metal salt thereof, disodium perfluorooctanesulfonylglutamate, 3- [ω-fluoroalkyl (carbon number 6 -11) Oxy] -1-alkyl (carbon number 3-4) sodium sulfonate, 3- [ω-fluoroalkanoyl (carbon number 6-8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (Carbon number 11-20) carboxylic acid or its metal salt, perfluoroalkyl carboxylic acid (carbon number 7-13) or its metal salt, perfluoroalkyl (carbon number 4-12) sulfonic acid or its metal salt, perfluoro Octanesulfonic acid diethanolamide, N-propyl-N- (2-hydroxyethyl ) Perfluorooctanesulfonamide, perfluoroalkyl (carbon number 6-10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (carbon number 6-10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (carbon number 6) -16) Ethyl phosphate ester and the like.

  As a commercial item of the anionic surfactant which has the said fluoroalkyl group, for example, Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.); Fluorard FC-93, FC-95, FC-98, FC-129 (manufactured by Sumitomo 3M); Unidyne DS-101, DS-102 (manufactured by Daikin Industries); Megafac F-110, F-120, F-113, F-191, F-812, F-833 (Manufactured by Dainippon Ink Co., Ltd.); Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products); Neos)).

-Emulsification or dispersion-
As a method of preparing an emulsified or dispersed liquid by emulsifying or dispersing the toner material in an aqueous medium, it is preferable to disperse the dissolved or dispersed toner material in the aqueous medium while stirring. There is no restriction | limiting in particular as a dispersion method, According to the objective, it can select suitably, For example, it can carry out using a well-known disperser etc. Examples of the disperser include a low speed shear disperser and a high speed shear disperser. When the toner material includes the active hydrogen group-containing compound and a polymer capable of reacting with the active hydrogen group-containing compound, an adhesive group is obtained by subjecting these to an extension reaction or a crosslinking reaction during emulsification or dispersion. The material is generated.

  The amount of the aqueous medium used in the step b is preferably 50 parts by mass to 2,000 parts by mass, and more preferably 100 parts by mass to 1,000 parts by mass with respect to 100 parts by mass of the toner material. When the amount used is less than 50 parts by mass, the toner material is in a poorly dispersed state, and toner particles having a predetermined particle size may not be obtained. When the amount exceeds 2,000 parts by mass, the production cost increases. Sometimes.

As described above, it is preferable that the acrylic resin fine particles B have a property of generating aggregates in an aqueous medium containing the anionic surfactant. Since the acrylic resin fine particles B have the property of forming aggregates in the aqueous medium containing the anionic surfactant, the acrylic resin fine particles B present on the water phase side during or after emulsification are used as a liquid of the toner material. It moves to the droplet surface and can easily adhere to the droplet surface of the toner material. That is, in the aqueous medium containing the anionic surfactant, the acrylic resin fine particles B are unstable and usually aggregate, and if there is a toner material droplet, When the attractive force is strong, a complex of different particles is formed.
The resulting composite of the toner material droplets and the acrylic resin fine particles B shows a strong adhesive force as it is, but after emulsification, the acrylic resin fine particles B move to the surface of the toner material droplets. After adhering to the droplet surface, it can be more firmly fixed to the toner surface by performing a heat treatment described later.

The emulsification or dispersion preferably contains a dispersant in the emulsification or dispersion, if necessary, from the viewpoint of stabilizing oil droplets and sharpening the particle size distribution while obtaining a desired shape.
The dispersant is not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include surfactants, sparingly water-soluble inorganic compound dispersants, polymeric protective colloids, acids such as calcium phosphate salts, alkalis Dispersants that can be dissolved in These may be used individually by 1 type and may use 2 or more types together. Among these, a surfactant is preferable, and an anionic surfactant is more preferable. As the anionic surfactant, the anionic surfactant contained in the aqueous medium can be used.

  Examples of the poorly water-soluble inorganic compound dispersant include tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite.

Examples of the polymeric protective colloid include acids, (meth) acrylic monomers containing a hydroxyl group, vinyl alcohol or ethers of vinyl alcohol, esters of vinyl alcohol and a compound containing a carboxyl group, amides Examples thereof include homopolymers or copolymers such as compounds or their methylol compounds, chlorides, those having a nitrogen atom or a heterocyclic ring thereof, polyoxyethylenes, and celluloses.
Examples of the acids include acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, and the like.
Examples of the (meth) acrylic monomer containing a hydroxyl group include β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, and γ-acrylate. -Hydroxypropyl, γ-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerin monoacrylate, Examples thereof include glycerin monomethacrylate, N-methylol acrylamide, N-methylol methacrylamide and the like.
Examples of the vinyl alcohol or ethers with vinyl alcohol include vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, and the like. Examples of esters of a compound containing vinyl alcohol and a carboxyl group include vinyl acetate, vinyl propionate, and vinyl butyrate. Moreover, as an amide compound or these methylol compounds, acrylamide, methacrylamide, diacetone acrylamide acid, or these methylol compounds etc. are mentioned, for example.
Examples of the chlorides include acrylic acid chloride and methacrylic acid chloride.
Examples of the homopolymer or copolymer such as those having a nitrogen atom or a heterocyclic ring thereof include vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, and ethylene imine.
Examples of the polyoxyethylene are polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene Examples thereof include oxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, and polyoxyethylene nonyl phenyl ester.
Examples of the celluloses include methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.
When using a dispersant that is soluble in acids and alkalis such as calcium phosphate, remove the calcium phosphate from fine particles by dissolving the calcium phosphate with an acid such as hydrochloric acid and then washing with water or decomposing with an enzyme. Is possible.

<Process c>
Step c is a step of preparing toner particles by removing an organic solvent from the emulsified or dispersed liquid.
The method for removing the organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. For example, (1) the temperature of the entire reaction system is gradually raised, and the organic solvent in the droplets (2) The emulsified or dispersed liquid is sprayed in a dry atmosphere to completely remove the organic solvent in the droplets to form toner fine particles. The method of evaporating and removing is mentioned. When the organic solvent is removed, toner particles are formed.

<Addition of resin fine particles B>
The resin fine particles B are added to an aqueous medium before emulsification or an emulsification or dispersion after emulsification. At this timing, since the organic solvent is present in the toner material droplets, the acrylic resin fine particles B adhere to the droplet surface and then enter the droplet surface to some extent, and after the organic solvent is removed, the toner base particles Desirable forms such as being adhered and fixed to the surface can be realized.
The resin fine particles B may be added while being dispersed with a high-speed shearing disperser, or may be added after emulsification by switching to low-speed stirring. It is done while watching.

<Other processes>
<< Cleaning process >>
The washing step is a step of forming a toner particle by removing the organic solvent and then washing the formed toner particle with ion-exchanged water to produce a dispersion having a desired conductivity.

<< Heating process >>
The heating step is a step of heat-treating the toner particle dispersion. Examples of the heat treatment include (1) a method of performing a heat treatment in a stationary state, and (2) a method of performing a heat treatment with stirring. When the heat treatment is performed, toner particles having a smooth surface are formed. Further, when the toner particles are dispersed with ion exchange water, the heat treatment may be performed before or after cleaning.
The obtained composite (toner particles) shows a strong adhesive force as it is, but after emulsification, the acrylic resin fine particles B move to the surface of the toner material droplets and are heated after adhering to the surface of the toner material droplets. By passing through the process, the toner surface can be more firmly fixed. The fixing temperature is preferably higher than the glass transition point of the polyester resin used for the toner base particles.

<< Dry classification process >>
The formed toner particles are dried and then classified as desired. The classification is performed, for example, by removing fine particle portions in a liquid by a cyclone, a decanter, centrifugation, or the like. The classification operation may be performed after obtaining the powder after drying.

  The toner particles thus obtained are mixed with particles such as a colorant, a release agent, and a charge control agent, and further a mechanical impact force is applied to the particles such as a release agent from the surface of the toner particles. Can be prevented from desorbing. As a method of applying a mechanical impact force, for example, a method of applying an impact force to a mixture with a blade rotating at high speed, a mixture of particles in a high-speed air stream and acceleration to mix particles or a composite particle is a suitable collision plate. The method of making it collide with. As an apparatus used for this method, for example, an ong mill (manufactured by Hosokawa Micron Co., Ltd.), an I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) and a pulverization air pressure are lowered, and a hybridization system (Nara Machinery Co., Ltd.) Co., Ltd.), Kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.

(Developer)
The developer comprises the toner of the present invention described above. The toner of the present invention may be used as a one-component developer, or may be mixed with a carrier and used as a two-component developer.
The weight average particle diameter of the carrier is preferably 15 μm to 40 μm. When the weight average particle size is less than 15 μm, carrier adhesion that causes the carrier to be transferred together in the transfer step is likely to occur. If the weight average particle diameter exceeds 40 μm, carrier adhesion is unlikely to occur, but if the toner concentration is increased in order to obtain a high image density, there is a risk that background staining will easily occur, and the dot diameter of the latent image Is small, the variation in dot reproducibility becomes large, and the graininess of the highlight portion may be deteriorated.

(Toner container)
The toner containing container contains the toner of the present invention in a container.
There is no restriction | limiting in particular as said container containing a toner, It can select suitably from well-known things, For example, what has a developer container main body and a cap etc. are mentioned suitably. There is no restriction | limiting in particular about the magnitude | size, a shape, a structure, a material, etc. as said developer container main body, According to the objective, it can select suitably. As the shape of the developer container main body, for example, the cylindrical shape is preferable, spiral irregularities are formed on the inner peripheral surface, and the toner as the contents can be transferred to the discharge port side by rotating, In addition, it is particularly preferable that part or all of the spiral portion has a bellows function. The material of the developer container main body is not particularly limited, and those having good dimensional accuracy are preferable. For example, a resin is preferable, and among them, for example, polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, Preferable examples include vinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin. The developer-containing container is easy to store and transport, has excellent handleability, and can be suitably used for replenishing the developer by being detachably attached to a process cartridge described later.

(Full-color image forming method and image forming apparatus)
The full-color image forming method includes a charging step, an exposure step, a development step, a primary transfer step, a secondary transfer step, a fixing step, and a cleaning step, and other steps appropriately selected as necessary. including. The toner used in the developing process needs to be the toner of the present invention described above.
Further, the image forming apparatus includes a charging unit, an exposure unit, a developing unit, a primary transfer unit, a secondary transfer unit, a fixing unit, and a cleaning unit, and other types appropriately selected as necessary. Including means. The toner used in the developing unit needs to be the toner of the present invention described above.
In the full-color image forming method, in the secondary transfer step, the linear velocity of transfer of the toner image to the recording material is 100 mm / sec to 1000 mm / sec, and the transfer time at the nip portion of the secondary transfer means is 0.5 msec. It is preferably ˜60 msec.

  Further, the full color image forming method preferably employs a tandem electrophotographic image forming process having a plurality of sets of electrophotographic photoreceptors, charging means, exposure means, developing means, primary transfer means, and cleaning means. In the so-called tandem type, in which a plurality of electrophotographic photosensitive members are arranged and developed one by one at each rotation, a latent image forming process, a developing process, and a transferring process are performed for each color to form a toner image of each color. Therefore, the difference between the single-color image formation speed and the full-color image formation speed is small, and there is an advantage that it can cope with high-speed printing. However, since each color toner image is formed on a separate electrophotographic photosensitive member and each color toner layer is stacked (color overlap) to form a full color image, the chargeability between the toner particles of each color is different. If the characteristics are varied, a difference occurs in the amount of toner developed by toner particles of each color, and the change in the hue of the secondary color due to color superposition is increased, resulting in a decrease in color reproducibility.

  In the toner used in the tandem type image forming method, the amount of developing toner for controlling the balance of each color is stabilized (there is no variation among the toner particles of each color), and the toner between the toner particles of each color is electronic. The adhesion to the photographic photosensitive member and the recording material is required to be uniform. In this regard, the toner of the present invention is suitable.

<Charging process>
The charging step is a step of charging the electrophotographic photosensitive member with a charging unit.
As the charging means, for example, the contact-type charging device shown in FIGS. 3 and 4 can be used.
Moreover, it is preferable that the charging means applies a DC voltage on which at least an alternating voltage is superimposed. By applying a DC voltage superimposed with an alternating voltage, the surface voltage of the electrophotographic photosensitive member can be stabilized to a desired value compared to the case where only a DC voltage is applied. It becomes. Further, it is preferable that the charging unit performs charging by bringing a charging member into contact with the electrophotographic photosensitive member and applying a voltage to the charging member. By further charging the electrophotographic photosensitive member with a charging member and applying a voltage to the charging member to perform charging, in particular, the effect of uniform charging obtained by applying a DC voltage superimposed with an alternating voltage can be further improved. Is possible.

<< Roller type charging device >>
FIG. 3 shows a schematic configuration of an example of a roller charging device (500) which is a kind of contact charging device. A photosensitive member (505) as an image bearing member, which is a member to be charged, is driven to rotate at a predetermined speed (process speed) in the direction of the arrow. A charging roller (501), which is a charging member brought into contact with the photosensitive member (505), includes a cored bar (502) and a conductive rubber layer (503) formed on the roller concentrically with the outer periphery of the cored bar (502). In the case of this figure, both ends of the mandrel are rotatably held by a bearing member (not shown) and are pressed against the photosensitive drum by a pressing means (not shown). The charging roller (501) rotates following the rotation of the photosensitive member (505). The charging roller (501) is formed to a diameter of 16 mm by coating a medium resistance conductive rubber layer (503) of about 100,000 Ω · cm on a core metal having a diameter of 9 mm. The cored bar (502) of the charging roller (501) and the illustrated power source (504) are electrically connected, and a predetermined bias is applied to the charging roller (501) by the power source (504). As a result, the peripheral surface of the photoconductor (505) is uniformly charged to a predetermined polarity and potential.

<< Fur brush type charging device >>
The shape of the charging device used in the present invention may take any form, such as a magnetic brush type charging device or a fur brush type charging device, in addition to the roller type charging device, according to the specifications and form of the electrophotographic apparatus. Can be selected. When a magnetic brush charging device is used, the magnetic brush uses, for example, various ferrite particles such as Zn-Cu ferrite as a charging member, a non-magnetic conductive sleeve for supporting the charging member, and a magnet roll included therein. Including. In addition, when using a fur brush type charging device, for example, as a material of the fur brush, a fur treated with carbon, copper sulfide, metal, metal oxide or the like is used, and this is treated with metal or other conductive treatment. A charging device is obtained by winding or sticking to a mandrel.

FIG. 4 shows a schematic configuration of an example of a contact-type brush charging device (510). A photoconductor (515) as an image carrier as a member to be charged is driven to rotate at a predetermined speed (process speed) in the direction of the arrow. A fur brush roller (511) constituted by a fur brush is brought into contact with the photoconductor (515) with a predetermined nip width with a predetermined pressing force against the elasticity of the brush portion (513).
The fur brush roller (511) as a contact charging device in this example is composed of a metal cored bar (512) having a diameter of 6 mm that also serves as an electrode, and a conductive rayon fiber REC manufactured by Unitika Ltd. as a brush part (513). A tape with -B piled is wound spirally into a roll brush with an outer diameter of 14 mm and a longitudinal length of 250 mm. The brush of the brush portion (513) has a density of 300 denier / 50 filaments and 155 brushes per square millimeter. This roll brush was inserted into a pipe having an inner diameter of 12 mm while rotating in one direction, and the brush and the pipe were set to be concentric, and left in a high-temperature and high-humidity atmosphere to bend and bevel.

The resistance value of the fur brush roller (511) is 1 × 10 ⁵ Ω at an applied voltage of 100V. This resistance value was converted from the current that flows when a fur brush roller is brought into contact with a metal drum having a diameter of φ30 mm with a nip width of 3 mm and a voltage of 100 V is applied. The resistance value of the brush-type charging device (510) is such that even when a low-voltage defective portion such as a pinhole is generated on the photosensitive member (515) to be charged, an excessive leak current flows into this portion. In order to prevent an image defect in which the nip portion is poorly charged, it is necessary to be 10 ⁴ Ω or more, and in order to sufficiently inject charges onto the surface of the photoreceptor (515), it is necessary to be 10 ⁷ Ω or less.

  As materials for the brush, in addition to REC-B manufactured by Unitika Ltd., REC-C, REC-M1, REC-M10, SA-7 manufactured by Toray Industries, Inc., Thunder manufactured by Nippon Kashiwa Co., Ltd. Ron, Kanebo's Beltron, Kuraray Co., Ltd.'s Kurabobo, rayon dispersed carbon, Mitsubishi Rayon Co., Ltd. global, etc. are conceivable. One brush is 3 denier to 10 denier, and preferably has a density of 10 filaments / bundle to 100 filaments / bundle and 80 / mm to 600 strands / mm. The hair foot is preferably 1 mm to 10 mm.

The fur brush roller (511) is rotationally driven at a predetermined peripheral speed (surface speed) in a direction (counter) opposite to the rotation direction of the photoconductor (515), and contacts the photoconductor surface with a speed difference. . By applying a predetermined charging voltage from the power source (514) to the brush roller (511), the surface of the rotating photoconductor is uniformly contact-charged to a predetermined polarity and potential.
In this example, the contact charging of the photoconductor (515) by the fur brush roller (511) is performed by direct injection charging, and the surface of the rotating photoconductor is almost equal to the charging voltage applied to the fur brush roller (511). Charged to the same potential.
In addition to the fur brush roller (511), the charging member used in the present invention may take any form such as a charging roller or a fur brush, and can be selected according to the specifications and form of the electrophotographic apparatus. It is. When a charging roller is used, it is generally used by coating a medium resistance rubber layer of about 100,000 Ω · cm on a cored bar. In the case of using a magnetic brush, the magnetic brush is composed of various ferrite particles such as Zn—Cu ferrite as a charging member, a non-magnetic conductive sleeve for supporting it, and a magnet roll included therein.

  As the magnetic brush as the contact charging member in this example, Zn—Cu ferrite particles having a volume average particle diameter of 25 μm and Zn—Cu ferrite particles having a volume average particle diameter of 10 μm are mixed at a mass ratio of 1: 0.05. Magnetic particles obtained by coating ferrite particles having a volume average particle diameter of 25 μm and having a peak at the position of each average particle diameter with a medium resistance resin layer were used. The contact charging member is composed of the coated magnetic particles prepared above, a nonmagnetic conductive sleeve for supporting the coated magnetic particles, and a magnet roll included therein, and the coated magnetic particles are 1 mm thick on the sleeve. And a charging nip having a width of about 5 mm was formed between the photosensitive member and the photosensitive member. The gap between the magnetic particle holding sleeve and the photosensitive member was about 500 μm. Further, the magnet roll is rotated so that the sleeve surface rubs in the opposite direction at twice as fast as the peripheral speed of the surface of the photoconductor, and the photoconductor and the magnetic brush are in uniform contact with each other. I did it.

<Exposure process>
The exposure step is a step of forming an electrostatic latent image on the charged electrophotographic photosensitive member by exposure means.

<Development process>
The developing step is a step of forming a toner image by a developing means containing toner on the electrophotographic photosensitive member on which the electrostatic latent image is formed.
In developing the latent image on the photoreceptor in the present invention, it is preferable to apply an alternating electric field. In the developing device (600) shown in FIG. 5, during development, a vibration bias voltage obtained by superimposing an AC voltage on a DC voltage is applied to the developing sleeve (601) as a developing bias by a power source (602). The background portion potential and the image portion potential are located between the maximum value and the minimum value of the vibration bias potential. As a result, an alternating electric field whose direction changes alternately is formed in the developing portion (603). In this alternating electric field, the developer toner and the carrier vibrate vigorously, and the toner (605) flies to the photosensitive member (604) by shaking off the electrostatic binding force to the developing sleeve (601) and the carrier. It adheres corresponding to the latent image. The toner (605) is a toner manufactured by the above-described manufacturing method of the present invention.

  The difference between the maximum value and the minimum value (the peak-to-peak voltage) of the vibration bias voltage is preferably 0.5 kV to 5 kV, and the frequency is preferably 1 kHz to 10 kHz. As the waveform of the vibration bias voltage, a rectangular wave, a sine wave, a triangular wave or the like can be used. As described above, the DC voltage component of the vibration bias is a value between the background part potential and the image part potential, but the value closer to the background part potential than the image part potential is more likely to cover the background part potential region. This is preferable for preventing toner adhesion.

  When the vibration bias voltage waveform is a rectangular wave, the duty ratio is preferably 50% or less. Here, the duty ratio is a ratio of time during which the toner is directed to the photosensitive member during one period of the vibration bias. By doing so, the difference between the peak value at which the toner is directed to the photoreceptor and the time average value of the bias can be increased, so that the movement of the toner is further activated and the potential of the latent image surface is increased. It can adhere to the distribution and improve the roughness and resolution. In addition, since the difference between the peak value of the carrier having a charge opposite to that of the toner and the time average value of the bias toward the photosensitive member can be reduced, the movement of the carrier is reduced, and the background portion of the latent image is reduced. The probability of carriers adhering to the substrate can be greatly reduced.

<Primary transfer process>
The primary transfer step is a step of transferring a toner image formed on the electrophotographic photosensitive member onto an intermediate transfer member by a primary transfer unit.

<Secondary transfer process>
The secondary transfer step is a step of transferring the toner image transferred onto the intermediate transfer member onto a recording material by a secondary transfer unit.

<Fixing process>
The fixing step is a step of fixing the toner image transferred onto the recording material onto the recording material by a fixing means including a heat and pressure fixing member.
The fixing means is composed of a magnetic metal and heated by electromagnetic induction, is stretched between a fixing roller arranged in parallel with the heating roller, the heating roller and the fixing roller, and is heated by the heating roller. At the same time, an endless belt-shaped toner heating medium (heating belt) rotated by these rollers is pressed against the fixing roller via the heating belt and rotated in the forward direction with respect to the heating belt to form a fixing nip portion. By having the pressure roller, the temperature of the fixing belt rises in a short time, and stable temperature control becomes possible. Even when a recording material having a rough surface is used, the fixing belt acts in a state corresponding to the surface of the transfer paper to some extent at the time of fixing, so that sufficient fixing property can be obtained.

  The fixing means is preferably oilless or a small amount of oil application type. In order to achieve this, it is preferable to fix a toner base particle containing a release agent (WAX) and further finely dispersed in the toner base particle. When the release agent is easily dispersed by the toner in which the release agent is dispersed in a small amount in the toner base particles, and the oil application effect is reduced in the oilless fixing device or in the minute amount oil application fixing device. In this case, the transfer of toner to the belt can be suppressed. In order for the release agent to be dispersed in the toner base particles, it is preferable that the release agent and the binder resin are not compatible. In order to finely disperse the release agent in the toner base particles, for example, there is a method of utilizing a kneading shear force at the time of toner production. The dispersion state of the release agent can be determined by observing a thin film slice of the toner base particles with a TEM. The dispersion diameter of the release agent is preferably small, but if it is too small, there are cases where the seepage during fixing is insufficient. Therefore, if the release agent can be confirmed at a magnification of 10,000, it is determined that the release agent exists in a dispersed state. If the size is 10,000 times and the release agent cannot be confirmed, even if finely dispersed, there is a case where the bleeding at the time of fixing is insufficient.

  As the fixing device used in the image forming method of the present invention, for example, the fixing device shown in FIG. 6 can be used. The fixing device shown in FIG. 6 includes a heating roller (710) heated by electromagnetic induction of the induction heating means (760), a fixing roller (720) (opposite rotating body) arranged in parallel with the heating roller (710). And an endless belt-like fixing belt that is stretched between a heating roller (710) and a fixing roller (720), heated by the heating roller (710), and rotated in the direction of arrow A by at least rotation of any of these rollers. A heat-resistant belt (toner heating medium) (730) and a pressure roller (740) that is pressed against the fixing roller (720) via the fixing belt (730) and rotates in the forward direction with respect to the fixing belt (730). (Pressure rotator).

The heating roller (710) is made of a hollow cylindrical magnetic metal member such as iron, cobalt, nickel, or an alloy of these metals, and has an outer diameter of, for example, 20 mm to 40 mm, and a thickness of, for example, 0.3 mm to 1. 0.0 mm, it has a low heat capacity and quick temperature rise.
The fixing roller (720) (opposite rotating body) is made of, for example, a metal core (721) made of stainless steel or the like, and a heat-resistant silicone rubber that is solid or foamed and is coated with the core (721). It consists of an elastic member (722). Then, in order to form a contact portion having a predetermined width between the pressure roller (740) and the fixing roller (720) by a pressing force from the pressure roller (740), the outer shape is set to about 20 mm to 40 mm. 710). The elastic member (722) has a thickness of about 4 mm to 6 mm. With this configuration, since the heat capacity of the heating roller (710) is smaller than the heat capacity of the fixing roller (720), the heating roller (710) is rapidly heated and the warm-up time is shortened.

  The fixing belt (730) stretched between the heating roller (710) and the fixing roller (720) is heated at the contact portion (W1) with the heating roller (710) heated by the induction heating means (760). . Then, the inner surface of the fixing belt (730) is continuously heated by the rotation of the heating roller (710) and the fixing roller (720). As a result, the entire belt is heated.

FIG. 7 shows a layer structure of the fixing belt (730). The belt (730) has the following four layers from the inner layer to the surface layer, and can be configured as follows.
-Substrate (731): Resin layer such as polyimide (PI) resin-Heat generation layer (732): Conductive material layer such as Ni, Ag, SUS-Intermediate layer (733): Elastic layer for uniform fixing-Release layer (734): Resin layer such as fluorine resin material for releasing effect and oil-less

  The thickness of the release layer (734) is preferably about 10 μm to 300 μm, particularly about 200 μm. In this manner, in the fixing device (700) as shown in FIG. 6, the toner image (T) formed on the recording material (770) is sufficiently wrapped by the surface layer portion of the fixing belt (730). The image (T) can be heated and melted uniformly. The thickness of the release layer (734), that is, the surface release layer is required to be at least 10 μm in order to ensure wear resistance over time. Further, when the thickness of the release layer (734) is larger than 300 μm, the heat capacity of the fixing belt (730) is increased and the time required for warm-up is increased. Further, the surface temperature of the fixing belt (730) is hardly lowered in the toner image fixing step, and the effect of aggregating the melted toner at the fixing portion outlet cannot be obtained, and the releasability of the fixing belt (730) is lowered. The toner of the toner image (T) adheres to the fixing belt (730), and so-called hot offset occurs. The heat generating layer (732) made of the above metal may be used as the base of the fixing belt (730), but the heat resistance of fluorine resin, polyimide resin, polyamide resin, polyamideimide resin, PEEK resin, PES resin, PPS resin, etc. A resin layer having properties may be used.

  The pressure roller (740) includes, for example, a metal core (741) made of a cylindrical member made of a metal having high thermal conductivity such as copper or aluminum, and heat resistance and toner provided on the surface of the metal core (741). It is comprised from the elastic member (742) with high mold release property. In addition to the above metal, SUS may be used for the core metal (741). The pressure roller (740) presses the fixing roller (720) via the fixing belt (730) to form the fixing nip (N). In this embodiment, the pressure roller (740) Is made harder than the fixing roller (720), so that the pressure roller (740) bites into the fixing roller (720) (and the fixing belt (730)), and this biting causes the recording material (770). Is along the circumferential shape of the surface of the pressure roller (740), so that the recording material (770) is easily separated from the surface of the fixing belt (730). The outer diameter of the pressure roller (740) is about 20 mm to 40 mm, which is the same as that of the fixing roller (720), but the wall pressure is about 0.5 mm to 2.0 mm, which is thinner than the fixing roller (720).

  As shown in FIG. 6, the induction heating means (760) for heating the heating roller (710) by electromagnetic induction includes an excitation coil (761) as a magnetic field generation means and a coil around which the excitation coil (761) is wound. And a guide plate (762). The coil guide plate (762) has a semi-cylindrical shape arranged close to the outer peripheral surface of the heating roller (710), and the excitation coil (761) is formed by using a single long excitation coil wire as the coil guide plate (762). ) Along the axial direction of the heating roller (710). The excitation coil (761) has an oscillation circuit connected to a drive power supply (not shown) whose frequency is variable. On the outside of the exciting coil (761), a semi-cylindrical exciting coil core (763) made of a ferromagnetic material such as ferrite is fixed to the exciting coil core support member (764) and is disposed close to the exciting coil (761). Yes.

<Cleaning process>
The cleaning step is a step of cleaning the transfer residual toner adhering to the surface of the electrophotographic photosensitive member having the toner image transferred onto the intermediate transfer member by the primary transfer unit, by the cleaning unit.

(Process cartridge)
The process cartridge according to the present invention integrally includes at least an electrophotographic photosensitive member and a developing unit that uses a toner as an electrostatic latent image formed on the electrophotographic photosensitive member, and is attached to and detached from the main body of the image forming apparatus. It's free. The developing means includes a toner manufactured by the above-described manufacturing method of the present invention.
The process cartridge of the present invention preferably further includes at least one means selected from the charging means, the transfer means, and the cleaning means.
As the developing unit and the charging unit, the above-described developing device and charging device can be preferably used.

  An example of the process cartridge of the present invention is shown in FIG. The process cartridge (800) shown in FIG. 8 includes a photoreceptor (801), a charging unit (802), a developing unit (803), and a cleaning unit (806). The operation of the process cartridge (800) will be described. The photosensitive member (801) is rotationally driven at a predetermined peripheral speed. In the rotating process, the photosensitive member (801) is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the charging means (802), and then image exposure means (not shown) such as slit exposure or laser beam scanning exposure. In this way, an electrostatic latent image is sequentially formed on the peripheral surface of the photoreceptor (801), and the formed electrostatic latent image is converted into a toner image by a developing means (802) and developed. The transferred toner image is sequentially transferred from the sheet feeding unit to the recording material fed in synchronization with the rotation of the photosensitive member (801) between the photosensitive member (801) and a transfer unit (not shown) by the transfer unit. Go. The recording material that has undergone image transfer is separated from the surface of the photosensitive member, introduced into an image fixing means (not shown), and fixed on the image, and printed out as a copy (copy). The surface of the photoreceptor (801) after the image transfer is cleaned by removing the transfer residual toner by the cleaning means (806), and after being further neutralized, it is repeatedly used for image formation.

  As the full-color image forming apparatus used in the full-color image forming method of the present invention, for example, the tandem image forming apparatus (100) shown in FIGS. 9 and 10 can be used. In FIG. 9, an image forming apparatus (100) includes an image writing unit (120Bk, 120C, 120M, 120Y), an image forming unit (130Bk, 130C, 130M, 130Y) for performing color image formation by electrophotography. The paper feeding unit (140) is mainly configured. Based on the image signal, image processing is performed by an image processing unit (not shown) and converted into black (Bk), cyan (C), magenta (M), and yellow (Y) color signals for image formation, It transmits to an image writing part (120Bk, 120C, 120M, 120Y). The image writing unit (120Bk, 120C, 120M, 120Y) is, for example, a laser scanning optical system including a laser light source, a deflector such as a rotary polygon mirror, a scanning imaging optical system, and a mirror group (none of which are shown). Yes, it has four writing optical paths corresponding to the color signals described above, and performs image writing corresponding to the color signals in the image forming units (130Bk, 130C, 130M, 130Y).

  The image forming unit (130Bk, 130C, 130M, 130Y) includes photoconductors (210Bk, 210C, 210M, 210Y) for black, cyan, magenta, and yellow, and photoconductors (210Bk, 210C, 210M and 210Y) are usually OPC photoreceptors. Around each of the photoconductors (210Bk, 210C, 210M, 210Y), there are charging devices (215Bk, 215C, 215M, 215Y), and laser light exposure units from the image writing unit (120Bk, 120C, 120M, 120Y). Developing devices for each color (200Bk, 200C, 200M, 200Y), primary transfer devices (230Bk, 230C, 230M, 230Y), cleaning devices (300Bk, 300C, 300M, 300Y), static eliminators (not shown), etc. It is arranged. The developing device (200Bk, 200C, 200M, 200Y) uses a two-component magnetic brush developing system. Further, an intermediate transfer belt (220) is interposed between each photoconductor (210Bk, 210C, 210M, 210Y) and the primary transfer device (230Bk, 230C, 230M, 230Y), and each intermediate transfer belt (220) is provided with each intermediate transfer belt (220). The toner images of the respective colors are sequentially superimposed and transferred from the photoconductor, and carry the toner image on each photoconductor.

  In some cases, a pre-transfer charger (502) as pre-transfer charging means is disposed outside the intermediate transfer belt (220) at a position after passing through the primary transfer position of the final color and before passing through the secondary transfer position. Is preferred. The pre-transfer charger (502) transfers the toner image before transferring the toner image on the intermediate transfer belt (220) transferred to the photosensitive member (210) to the transfer paper as a recording material. The toner image is uniformly charged to the same polarity as the toner image.

  The toner image on the intermediate transfer belt (220) transferred from each photoconductor (210Bk, 210C, 210M, 210Y) includes a halftone portion and a solid portion, or includes a portion where the amount of toner overlap is different. Therefore, the charge amount may vary. Further, there may be a case where the charge amount varies in the toner image on the intermediate transfer belt (220) after the primary transfer due to the peeling discharge generated in the gap on the downstream side adjacent to the primary transfer portion in the intermediate transfer belt moving direction. . Such variation in the charge amount in the same toner image reduces the transfer margin at the secondary transfer portion that transfers the toner image on the intermediate transfer belt (220) onto the transfer paper. Therefore, the toner image before being transferred to the transfer paper by the pre-transfer charger is uniformly charged to the same polarity as the toner image, thereby eliminating the variation in the charge amount in the same toner image and the transfer margin at the secondary transfer portion. Has improved.

  As described above, according to this image forming method, the toner image on the intermediate transfer belt (220) transferred from each photoconductor (210Bk, 210C, 210M, 210Y) is uniformly charged by the pre-transfer charger (502). Even if there is a variation in the charge amount in the toner image on the intermediate transfer belt (220), the transfer characteristics in the secondary transfer portion are made almost constant across the portions of the toner image on the intermediate transfer belt (220). Can do. Therefore, it is possible to suppress a reduction in transfer margin when transferring to transfer paper and to stably transfer a toner image.

  In this image forming method, the amount of charge charged by the pre-transfer charger varies depending on the moving speed of the intermediate transfer belt (220) that is the object to be charged. For example, if the moving speed of the intermediate transfer belt (220) is slow, the time for the same portion of the toner image on the intermediate transfer belt (220) to pass through the charging area by the pre-transfer charger becomes long, and the charge amount increases. Conversely, when the moving speed of the intermediate transfer belt (220) is fast, the charge amount of the toner image on the intermediate transfer belt (220) becomes small. Therefore, when the moving speed of the intermediate transfer belt (220) changes while the toner image on the intermediate transfer belt (220) passes through the charging position by the pre-transfer charger, the intermediate transfer belt (220 It is desirable to control the pre-transfer charger so that the charge amount with respect to the toner image does not change in the middle according to the movement speed of ().

  Conductive rollers (241), (242), and (243) are provided between the primary transfer devices (230Bk, 230C, 230M, and 230Y). After the transfer paper is fed from the paper feed unit (140), it is carried on the transfer belt (500) via the registration roller pair (160), and the intermediate transfer belt (220) and the transfer belt (500) are in contact with each other. Then, the toner image on the intermediate transfer belt (220) is transferred to the transfer paper by the secondary transfer roller (600), and a color image is formed.

  Then, the transfer paper after image formation is conveyed to the fixing device (150) by the secondary transfer belt (180), and the image is fixed to obtain a color image. The toner on the intermediate transfer belt (220) remaining without being transferred is removed from the belt by the intermediate transfer belt cleaning device (260).

  Since the toner polarity on the intermediate transfer belt (220) before transfer onto the transfer paper is the same negative polarity as that during development, a positive transfer bias voltage is applied to the secondary transfer roller (170), and the toner is transferred. It is transferred onto paper. The nip pressure at this portion affects the transfer property and greatly affects the fixability. Further, the toner on the intermediate transfer belt (220) remaining without being transferred is discharged and charged to the positive polarity side and charged from 0 to the positive side at the moment when the transfer paper and the intermediate transfer belt (220) are separated. Note that the toner image formed when the transfer paper is jammed or in the non-image area is not affected by the secondary transfer, and thus remains of negative polarity.

  The thickness of the photosensitive layer is 30 μm, the beam spot diameter of the optical system is 50 × 60 μm, and the light quantity is 0.47 mW. The developing process is carried out with the charging (exposure side) potential V0 of the photoconductor (black) (210Bk) being −700V, the post-exposure potential VL being −120V, the developing bias voltage being −470V, that is, the developing potential 350V. The visible image of the toner (black) formed on the photoconductor (black) (210Bk) is then transferred (intermediate transfer belt and transfer paper) and completed as an image through a fixing process. First, all colors are transferred from the primary transfer device (230Bk, 230C, 230M, 230Y) to the intermediate transfer belt (220), and then applied to a transfer sheet by applying a bias to another secondary transfer roller (170). Transcribed.

  Next, the photoconductor cleaning device will be described in detail. In FIG. 9, each developing device (200Bk, 200C, 200M, 200Y) and each cleaning device (300Bk, 300C, 300M, 300Y) are connected to each other by a toner transfer pipe (250Bk, 250C, 250M, 250Y). (Dotted line in FIG. 9). Each toner transfer pipe (250Bk, 250C, 250M, 250Y) contains a screw (not shown), and the toner collected by each cleaning device (300Bk, 300C, 300M, 300Y) Each developing device (200Bk, 200C, 200M, 200Y) is transferred.

  In the conventional direct transfer method using the combination of the four photosensitive drums and the belt conveyance, paper dust adheres when the photoreceptor and the transfer paper come into contact with each other, and the paper dust is contained when the toner is collected. The image was deteriorated such as toner missing and could not be used. Furthermore, in the conventional system combining a single photoconductor drum and intermediate transfer, the use of an intermediate transfer member eliminates paper dust adhesion to the photoconductor during transfer paper transfer, but recycling of residual toner on the photoconductor In practice, it is practically impossible to separate the mixed color toners. There is also a proposal to use a mixed color toner as a black toner, but even if all the colors are mixed, it does not become black, and the color changes depending on the print mode. Therefore, it is impossible to recycle the toner with one photoconductor configuration.

  On the other hand, in this full-color image forming apparatus, since the intermediate transfer belt (220) is used, paper dust is hardly mixed, and adhesion of paper dust to the intermediate transfer belt (220) during paper transfer is prevented. The Since each photoconductor (210Bk, 210C, 210M, 210Y) uses independent color toner, it is not necessary to contact or separate each photoconductor cleaning device (300Bk, 300C, 300M, 300Y), and only the toner is reliably collected. can do.

  The positively charged toner remaining on the intermediate transfer belt (220) is cleaned by a conductive fur brush (262) to which a negative voltage is applied. The method of applying a voltage to the conductive fur brush (262) is exactly the same as that of the conductive fur brush (261) except for the polarity. The toner remaining without being transferred is also almost cleaned by the two conductive fur brushes (261) and (262). Here, toner, paper powder, talc, and the like remaining without being cleaned by the conductive fur brush (262) are negatively charged by the negative voltage of the conductive fur brush (262). The next black primary transfer is transfer by a positive voltage, and negatively charged toner or the like is attracted to the intermediate transfer belt (220) side, so that the transfer to the photosensitive member (black) (210Bk) side can be prevented.

  Next, the intermediate transfer belt (220) used in this image forming apparatus will be described. As described above, the intermediate transfer belt is preferably a single resin layer, but may have an elastic layer or a surface layer as necessary.

  There is no restriction | limiting in particular as the resin material which comprises the said resin layer, According to the objective, it can select suitably, For example, a polycarbonate, a fluororesin (ETFE, PVDF), a polystyrene, chloropolystyrene, poly-alpha-methyl Styrene, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer (styrene-methyl acrylate copolymer) Styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylic acid ester copolymer (styrene- Methyl methacrylate copolymer, styrene-ethyl methacrylate Polymers, styrene-phenyl methacrylate copolymers, etc.), styrene resins such as styrene-α-methyl acrylate acrylate copolymers, styrene-acrylonitrile-acrylic acid ester copolymers, etc. Polymer or copolymer), methyl methacrylate resin, butyl methacrylate resin, ethyl acrylate resin, butyl acrylate resin, modified acrylic resin (silicone modified acrylic resin, vinyl chloride resin modified acrylic resin, acrylic / urethane resin, etc.) , Vinyl chloride resin, styrene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, rosin modified maleic acid resin, phenol resin, epoxy resin, polyester resin, polyester polyurethane resin, polyethylene, polypropylene, polybutadiene, polychlorinated Vinylidene, ionomer resins, polyurethane resins, silicone resins, ketone resins, ethylene - ethyl acrylate copolymer, xylene resin and polyvinyl butyral resin, polyamide resin and modified polyphenylene oxide resins. These may be used individually by 1 type and may use 2 or more types together.

  Moreover, there is no restriction | limiting in particular as an elastic material (elastic material rubber | gum, elastomer) which comprises the said elastic layer, According to the objective, it can select suitably, For example, butyl rubber, fluorine-type rubber, acrylic rubber, EPDM, NBR , Acrylonitrile-butadiene-styrene rubber natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, ethylene-propylene rubber, ethylene-propylene terpolymer, chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, urethane rubber, syndiotactic 1,2-polybutadiene, epichlorohydrin rubber, ricone rubber, fluorine rubber, polysulfide rubber, polynorbornene rubber, hydrogenated nitrile rubber, thermoplastic elastomer (eg, polystyrene, polyolefin, polyvinyl chloride) System, polyurethane, polyamide, polyurea, polyester, fluorocarbon resin, etc.) and the like. These may be used individually by 1 type and may use 2 or more types together.

  Further, the material for the surface layer is not particularly limited, but a material for reducing the adhesive force of the toner to the surface of the intermediate transfer belt and improving the secondary transfer property is required. For example, materials that use one or more of polyurethane, polyester, epoxy resin, etc. to reduce surface energy and increase lubricity, such as fluororesin, fluorine compound, fluorocarbon, titanium dioxide, silicon carbide, etc. These powders and particles can be used by dispersing one type or two or more types or particles having different particle sizes. Further, it is also possible to use a material having a surface energy reduced by forming a fluorine-rich layer on the surface by heat treatment, such as a fluorine-based rubber material.

  A resistance value adjusting conductive agent is added to the resin layer and the elastic layer. The resistance value adjusting conductive agent is not particularly limited and can be appropriately selected according to the purpose. For example, carbon black, graphite, metal powder such as aluminum and nickel, tin oxide, titanium oxide, antimony oxide, Conductive metal oxide such as indium oxide, potassium titanate, antimony oxide-tin oxide composite oxide (ATO), indium oxide-tin oxide composite oxide (ITO), conductive metal oxides are barium sulfate, silicic acid It may be coated with insulating fine particles such as magnesium and calcium carbonate.

  FIG. 10 shows another example of the image forming apparatus used in the image forming method of the present invention, which is a copying apparatus (100) provided with a tandem indirect transfer type electrophotographic image forming apparatus. In FIG. 10, (101) is a copying apparatus main body, (200) is a paper feed table on which it is placed, (300) is a scanner mounted on the copying apparatus main body (101), and (400) is an automatic document to be mounted thereon. It is a transport device (ADF). The copying machine main body (101) is provided with an endless belt-shaped intermediate transfer member (10) in the center.

  As shown in FIG. 10, in this example, the three support rollers (14), (15), and (16) are wound around and can be rotated and conveyed clockwise in the figure. In this illustrated example, an intermediate transfer body cleaning device (17) for removing residual toner remaining on the intermediate transfer body (10) after image transfer is provided on the left of the second support roller (15) among the three. Further, among the three, the intermediate transfer member (10) stretched between the first support roller (14) and the second support roller (15) has yellow, cyan and magenta along the transport direction. The four black image forming means (18) are arranged side by side to constitute a tandem image forming apparatus (20).

  An exposure device (21) is further provided on the tandem image forming device (20) as shown in FIG. On the other hand, a secondary transfer device (22) is provided on the opposite side of the intermediate transfer member (10) from the tandem image forming device (20). In the illustrated example, the secondary transfer device (22) includes a secondary transfer belt (24), which is an endless belt, spanned between two rollers (23), and the second transfer device (22) passes through an intermediate transfer member (10). 3 is pressed against the support roller (16), and the image on the intermediate transfer body (10) is transferred to the sheet. Next to the secondary transfer device (22), a fixing device (25) for fixing the transferred image on the sheet is provided. The fixing device (25) is configured by pressing a pressure roller (27) against a fixing belt (26) which is an endless belt. The secondary transfer device (22) described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device (25). Of course, as the secondary transfer device (22), a transfer roller or a non-contact charger may be disposed. In such a case, it is difficult to provide this sheet conveying function together. In the illustrated example, a sheet is placed under such a secondary transfer device (22) and a fixing device (25) in order to record an image on both sides of the sheet in parallel with the tandem image forming device (20). A sheet inverting device (28) for inverting is provided.

  When making a copy using this tandem image forming apparatus, the original is set on the original table (30) of the automatic original feeder (400). Alternatively, the automatic document feeder (400) is opened, a document is set on the contact glass (32) of the scanner (300), and the automatic document feeder (400) is closed and pressed by it.

  When a start switch (not shown) is pressed, when the document is set on the automatic document feeder (400), the document is transported and moved onto the contact glass (32), and then the contact glass (32). ) When a document is set on the scanner, the scanner (300) is immediately driven to travel on the first traveling body (33) and the second traveling body (34). Then, the first traveling body (33) emits light from the light source, and the reflected light from the document surface is further reflected toward the second traveling body (34) and reflected by the mirror of the second traveling body (34). Then, the image is placed in the reading sensor (36) through the imaging lens (35) and the content of the original is read.

  When a start switch (not shown) is pressed, one of the support rollers (14), (15), and (16) is driven to rotate by the drive motor (not shown), and the other two support rollers are driven to rotate. The transfer body (10) is rotated and conveyed. At the same time, the individual image forming means (18) rotates the photoconductor (40) to form black, yellow, magenta, and cyan monochrome images on each photoconductor (40). Then, along with the conveyance of the intermediate transfer member (10), these monochrome images are sequentially transferred to form a composite color image on the intermediate transfer member (10).

  On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers (42) of the paper feed table (200) is selectively rotated, and one of paper feed cassettes (44) provided in multiple stages in the paper bank (43). The sheet is fed out from the sheet, separated one by one by a separation roller (45), put into a sheet feeding path (46), and conveyed by a conveying roller (47) to a sheet feeding path (48) in the copying machine main body (100). Guide and stop against the registration roller (49).

  Alternatively, the sheet feeding roller (50) is rotated to feed out the sheets on the manual feed tray (51), separated one by one by the separation roller (52), and placed in the manual sheet feeding path (53). ) And stop.

  Then, the registration roller (49) is rotated in synchronization with the composite color image on the intermediate transfer member (10), and the sheet is fed between the intermediate transfer member (10) and the secondary transfer device (22). The image is transferred by the next transfer device (22) and a color image is recorded on the sheet.

  The sheet after the image transfer is conveyed by the secondary transfer device (22) and sent to the fixing device (25). The fixing device (25) applies heat and pressure to fix the transferred image, and then the switching claw. It is switched at (55), discharged by the discharge roller (56), and stacked on the discharge tray (57). Alternatively, it is switched by the switching claw (55) and put into the sheet reversing device (28), where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then the paper discharge tray (56) is discharged by the discharge roller (56). 57) Drain up.

  On the other hand, the intermediate transfer member (10) after the image transfer is removed by the intermediate transfer member cleaning device (17) to remove residual toner remaining on the intermediate transfer member (10) after the image transfer, and the tandem image forming device (20). To prepare for image formation again. Here, the registration roller (49) is generally used while being grounded, but it is also possible to apply a bias for removing paper dust from the sheet.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not restrict | limited to a following example . However, Example 9 is a reference example.
The acid value, the number average molecular weight and the weight average molecular weight, and the glass transition point (Tg) were measured as follows.

[Measurement of acid value]
Based on the measurement method described in JIS K0070-1992, the measurement was performed under the following conditions. However, when the sample did not dissolve, dioxane, tetrahydrofuran or the like was used as the solvent.
The acid value is specifically determined by the following procedure.
Measuring device: automatic potentiometric titrator DL-53 Titorator
(Metler Toledo)
Electrode used: DG113-SC (manufactured by METTLER TOLEDO)
Analysis software: LabX Light Version 1.00.000
Calibration of apparatus: A mixed solvent of 120 ml of toluene and 30 ml of ethanol was used.
Measurement temperature: 23 ° C
The measurement can be calculated by the apparatus described above, but specifically, the calculation was performed as follows.
The solution was titrated with an alcohol solution of N / 10 potassium hydroxide standardized in advance, and the acid value was determined from the consumption of the alcohol potassium hydroxide solution by the following calculation.
Acid value = KOH (ml) x N x 56.1 / sample weight (where N is a factor of N / 10 KOH)

[Measurement of number average molecular weight and weight average molecular weight]
The number average molecular weight and the weight average molecular weight were measured by GPC (gel permeation chromatography) as follows. The column was stabilized in a 40 ° C. heat chamber, THF as a solvent was passed through the column at this temperature at a flow rate of 1 ml / min, and the concentration of the sample was adjusted to 0.05% to 0.6% by weight. Measurement was performed by injecting 50 μl to 200 μl of the sample solution. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the prepared calibration curve and the count using several types of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Or the weight average molecular weights made by Toyo Soda Industry Co., Ltd. are 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3 It is suitable to use a standard polystyrene sample of at least about 10 points using 9.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ . An RI (refractive index) detector was used as the detector.

[Measurement of glass transition point (Tg)]
The glass transition point (Tg) was measured with a Rigaku THRMOFLEX TG8110 manufactured by Rigaku Corporation at a temperature increase rate of 10 ° C./min.
A method for measuring Tg will be outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used.
First, about 10 mg of a sample was placed in an aluminum sample container, placed on a holder unit, and set in an electric furnace. Next, after heating from room temperature to 150 ° C. at a rate of temperature increase of 10 ° C./min, the sample is allowed to stand at 150 ° C. for 10 minutes, and then the sample is cooled to room temperature and left for 10 minutes. DSC measurement was performed by heating at a heating rate of 10 ° C./min. Tg was calculated from the contact point between the tangent line of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

<Synthesis of Unmodified Polyester Resin (Low Molecular Weight Polyester) C>
(Synthesis Example 1)
-Synthesis of unmodified polyester resin C1-
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 67 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 84 parts by mass of bisphenol A propion oxide 3 mol adduct, 274 parts by mass of terephthalic acid, and dibutyltin 2 parts by mass of oxide was added and allowed to react at 230 ° C. for 8 hours under normal pressure. Next, the reaction solution was reacted under reduced pressure of 10 mmHg to 15 mmHg for 5 hours to synthesize [unmodified polyester resin C1].
The obtained [unmodified polyester resin C1] has an acid value of 18 mgKOH / g, a number average molecular weight (Mn) of 2,100, a weight average molecular weight (Mw) of 5,500, and a glass transition point (Tg) of 50 ° C. Met.

(Synthesis Examples 2 to 7)
-Synthesis of unmodified polyester resins C2 to C7-
In Synthesis Example 1, as shown in Table 1 below, [Polyester Resin C2] to [Polyester Resin C7] were respectively synthesized in the same manner as Synthesis Example 1 except that the blending amount of the polyester resin material was changed.
About the obtained [Polyester resin C1]-[Polyester resin C7], it measured about the acid value, the number average molecular weight (Mn), the weight average molecular weight (Mw), and the glass transition point similarly to [Polyester resin C1]. . The results are shown in Table 2.

<Synthesis of prepolymer>
(Synthesis Example 8)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 682 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 81 parts by mass of bisphenol A propylene oxide 2 mol adduct, 283 parts by mass of terephthalic acid, trimellitic anhydride 22 parts by mass of acid and 2 parts by mass of dibutyltin oxide were charged and reacted at 230 ° C. for 8 hours under normal pressure. Subsequently, it was made to react under reduced pressure of 10mHg-15mHg for 5 hours, and the intermediate polyester was synthesize | combined. The obtained intermediate polyester has a number average molecular weight (Mn) of 2,100, a weight average molecular weight (Mw) of 9,600, a glass transition temperature (Tg) of 55 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl group. The value was 49 mgKOH / g.
Next, 411 parts by mass of the intermediate polyester, 89 parts by mass of isophorone diisocyanate, and 500 parts by mass of ethyl acetate are charged in a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, and reacted at 100 ° C. for 5 hours. [Prepolymer] (polymer capable of reacting with the active hydrogen group-containing compound) was synthesized. The obtained [prepolymer] had a free isocyanate content of 1.60% by mass, and the solid content concentration of the prepolymer (after standing at 150 ° C. for 45 minutes) was 50% by mass.

<Preparation of styrene-acrylic resin fine particles A>
(Synthesis Example 9)
-Synthesis of styrene-acrylic resin fine particles A1-
In a reaction vessel in which a stir bar and a thermometer are set, 683 parts by mass of water, 16 parts by mass of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts by mass of styrene, methacrylic acid When 83 parts by mass, 110 parts by mass of butyl acrylate, and 1 part by mass of ammonium persulfate were charged and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 35 parts by mass of a 1% by mass ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours to give a vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). An aqueous dispersion of [Styrene-acrylic resin fine particles A1] was obtained. [Styrene-acrylic resin fine particles A1] had a volume average particle size (measured by LA-920 manufactured by Horiba, Ltd.) of 40 nm, an acid value of 180 mgKOH / g, a weight average molecular weight of 350,000, and a Tg of 65 ° C. Moreover, as a result of measuring the swelling property and the compatibility with the polyester resin in accordance with the following method, the [styrene-acrylic resin fine particles A1] are not compatible with the polyester resin as the binder resin and have few cross-linked structures. Therefore, it turned out that it shows a high swelling property.

[Evaluation of resin particle size]
The measurement of the dispersed particle size distribution was measured using “Microtrac UPA-150” (manufactured by Nikkiso Co., Ltd.), and the analysis software “Microtrac Particle Size Analyzer-Ver.10.1.2-016EE” (manufactured by Nikkiso Co., Ltd.) was used. And analyzed. Specifically, the toner material liquid and then the solvent used for the toner material liquid preparation were added to a glass 30 ml sample bottle to prepare a 10 mass% dispersion. The obtained dispersion was subjected to a dispersion treatment for 2 minutes with an “ultrasonic wave disperser W-113MK-II” (manufactured by Honda Electronics Co., Ltd.).
After measuring the background with the solvent used for the toner material liquid to be measured, the dispersion was dropped, and the dispersed particle size was measured under the condition that the sample loading value of the measuring device was in the range of 1-10. In this measurement method, it is important to measure under the condition that the sample loading value of the measuring device is in the range of 1 to 10 from the viewpoint of measurement reproducibility of the dispersed particle size. In order to obtain the sample loading value, it is necessary to adjust the dripping amount of the dispersion.
Measurement and analysis conditions were set as follows.
Distribution display: Volume, particle size classification selection: standard, number of channels: 44, measurement time: 60 seconds, number of measurements: once, particle permeability: transmission, particle refractive index: 1.5, particle shape: non-spherical, density : 1 g / cm ³ .
The value of the solvent refractive index used was the value of the solvent used in the toner material liquid among the values described in “Guidelines on Input Conditions at Measurement” published by Nikkiso Co., Ltd.

[Swellability evaluation of resin fine particles]
Various resin fine particles having a difference in swellability were added to 30 ml of ASONE screw vials so that each of them was 20 mm from the bottom with a measuring pipette, and 10 ml of ethyl acetate was added with a measuring pipette and allowed to stand for 24 hours. However, the emulsion of resin fine particles having a white color phase-separated on the lower side and ethyl acetate on the upper side. And the difference in swelling property was evaluated by observing the height of the resin fine particle emulsion which has white from the bottom of a screw vial. Those having a high swelling property have a high height. The degree of swelling was determined as follows. In the present invention, “swell” refers to those evaluated as ◎, ○, Δ.
〔Evaluation criteria〕
◎: 25 mm or more Swells well ○: 21 mm or more, less than 25 mm Swells △: 20 mm or more, less than 21 mm Insufficient swelling ×: Less than 20 mm Does not swell

[Compatibility of resin fine particles with polyester resin]
50 parts of a mixture of polyester resin and acrylic resin fine particles mixed in a toner blending ratio was added to 50 parts of ethyl acetate, and the compatibility was judged as follows.
〔Evaluation criteria〕
Compatibility: The mixed solution becomes transparent.
Incompatible: Acrylic resin fine particles swollen in the mixed solution can be confirmed.

(Synthesis Examples 10-20)
-Synthesis of styrene-acrylic resin fine particles A2 to A11-
In Synthesis Example 9, as shown in Table 3 below, [Styrene-acrylic resin fine particles A2] to [Styrene-acrylic resin] in the same manner as in Synthesis Example 12 except that the blending amount of the styrene-acrylic resin fine particle A1 material was changed. An aqueous dispersion of fine particles A12] was obtained.
About the obtained [styrene-acrylic resin fine particles A2] to [styrene-acrylic resin fine particles A11], in the same manner as [styrene-acrylic resin fine particles A1], the volume average particle diameter, the acid value, the weight average molecular weight, and the glass transition point. Was measured. The results are shown in Table 4. Further, in the same manner as [Styrene-acrylic resin fine particles A1], the swelling property and the compatibility with the polyester resin were measured. The results are shown in Table 5.

<Preparation of acrylic resin fine particles B>
(Synthesis Example 21)
-Synthesis of acrylic resin fine particles B1-
In a reaction vessel in which a stir bar and a thermometer are set, 683 parts by mass of water, 10 parts by mass of distearyldimethylammonium chloride (cation DS, manufactured by Kao Corporation), 144 parts by mass of methyl methacrylate, 46 parts by mass of butyl acrylate, methacrylic acid When 4 parts by mass, 2 parts by mass of ethylene glycol dimethacrylate and 1 part by mass of ammonium persulfate were charged and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The mixture was heated to raise the temperature in the system to 65 ° C. and reacted for 10 hours. Further, 30 parts by mass of a 1% by mass aqueous ammonium persulfate solution was added, and the mixture was aged at 75 ° C. for 5 hours to give a vinyl resin (copolymer of methyl methacrylate-butyl acrylate-methacrylic acid-ethylene glycol dimethacrylate) [acrylic. An aqueous dispersion of resin fine particles B1] was obtained. [Acrylic resin fine particles B1] had a volume average particle size (measured by LA-920 manufactured by Horiba, Ltd.) of 50 nm, an acid value of 10 mgKOH / g, a mass average molecular weight Mw of 400,000, and a Tg of 60 ° C. Further, as in the case of [Styrene-acrylic resin fine particles A1], as a result of measuring the swelling property and compatibility with the polyester resin, the [acrylic resin fine particles B1] are not compatible with the polyester resin as the binder resin, and It was found that since the cross-linked structure is small, it exhibits high swellability.

(Synthesis Examples 22 to 31)
-Synthesis of acrylic resin fine particles B2 to B11-
In Synthesis Example 21, as shown in Table 6 below, [Acrylic resin particles B2] to [Acrylic resin particles B11] were respectively synthesized in the same manner as Synthesis Example 21 except that the blending amount of the acrylic resin particles was changed.
The obtained [Acrylic resin fine particles B2] to [Acrylic resin fine particles B11] were measured in the same manner as [Acrylic resin fine particles B1], in terms of volume average particle diameter, acid value, mass average molecular weight, and glass transition point. The results are shown in Table 7. Further, the swelling property and the compatibility with the polyester resin were measured in the same manner as in [Acrylic resin fine particles B1]. The results are shown in Table 8.

Example 1
<Manufacture of toner 1>
-Preparation of masterbatch (MB)-
1000 parts by weight of water, 540 parts by weight of carbon black (“Printtex 35”; manufactured by Degussa, DBP oil absorption = 42 ml / 100 g, pH = 9.5), and 1200 parts by weight of [unmodified polyester C1] were added to a Henschel mixer ( (Mitsui Mining Co., Ltd.). The mixture was kneaded with a two-roller at 150 ° C. for 30 minutes, rolled and cooled, and pulverized with a pulverizer (manufactured by Hosokawa Micron Corporation) to prepare [Masterbatch].

-Preparation of toner material solution or dispersion-
In a beaker, 100 parts by mass of [Unmodified Polyester C1] and 130 parts by mass of ethyl acetate were stirred and dissolved. Next, 10 parts by mass of carnauba wax (molecular weight = 1,800, acid value = 2.5 mgKOH / g, penetration = 1.5 mm (40 ° C.)) and 10 parts by mass of [Masterbatch] were charged, and bead mill ( Using “Ultra Visco Mill” (manufactured by Imex Co., Ltd.), the raw material solution was passed through 3 passes under the condition that the liquid feeding speed was 1 kg / hr, the disk peripheral speed was 6 m / s, and 80% by volume of 0.5 mm zirconia beads were filled. After preparing 40 parts by mass of [Prepolymer] and stirring, [Dissolution or Dispersion of Toner Material] was prepared.

-Preparation of aqueous medium phase-
660 parts by mass of water, 25 parts by mass of an aqueous dispersion of the above-mentioned [styrene-acrylic resin fine particles A1], 25 parts by mass of an aqueous solution of 48.5% by mass sodium dodecyl diphenyl ether disulfonate (“Eleminol MON-7”; manufactured by Sanyo Chemical Industries) And 60 parts by mass of ethyl acetate were mixed and stirred to obtain a milky white liquid (aqueous phase). Further, 50 parts by mass of [Acrylic resin fine particles B1] was added to obtain [Aqueous medium phase]. When the [aqueous medium phase] was observed with an optical microscope, an aggregate of several hundred μm was observed. [Aqueous medium phase] was stirred with a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at a rotational speed of 8,000 rpm, and the aggregates were loosened and confirmed by an optical microscope that they could be dispersed into small aggregates of several μm did. Therefore, it was expected that [acrylic resin fine particles B1] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material. As described above, the acrylic resin fine particles cause aggregation but are loosened by shearing in order to uniformly adhere to the toner surface.

-Preparation of emulsion or dispersion-
[Aqueous medium phase] 150 parts by mass is put in a container, and stirred using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at a rotational speed of 12,000 rpm. Part was added and mixed for 10 minutes to prepare [emulsification or dispersion] (emulsification slurry).

-Removal of organic solvent-
In a flask equipped with a degassing pipe, a stirrer and a thermometer, 100 parts by mass of [emulsification or dispersion] was charged, and the solvent was removed under reduced pressure at 30 ° C. for 12 hours while stirring at a stirring peripheral speed of 20 m / min. Solvent removal slurry].

-Washing-
[Solvent removal slurry] After filtering the whole amount under reduced pressure, 300 parts by mass of ion-exchanged water was added to the obtained filter cake, and after mixing and redispersion (at 12,000 rpm for 10 minutes) with a TK homomixer And filtered. Further, 300 parts by mass of ion-exchanged water was added to the obtained filter cake, mixed with a TK homomixer (10 minutes at a rotation speed of 12,000 rpm), and then filtered three times to re-dispersed slurry. When the conductivity became 0.1 μS / cm or more and 10 μS / cm or less, [washing slurry] was obtained.

-Heat treatment-
The obtained [washing slurry] was heated in a flask equipped with a stirrer and a thermometer at 50 ° C. with stirring at a stirring peripheral speed of 20 m / min for 60 minutes, and adhered to the particle surface of [unmodified polyester resin C1]. [Acrylic resin fine particles B1] were fixed and then filtered to obtain [Filter cake].

-Drying-
The obtained [Filtration cake] was dried at 45 ° C. for 48 hours with a forward air dryer, and sieved with a mesh having an opening of 75 μm to obtain [Base particle 1].

-External treatment-
[Base Particle 1] For 100 parts by mass, 0.6 part by mass of hydrophobic silica having a volume average particle diameter of 100 nm, 1.0 part by mass of titanium oxide having a volume average particle diameter of 20 nm, and hydrophobic having a volume average particle diameter of 15 nm 0.8 parts by weight of fine silica powder was mixed with a Henschel mixer to obtain [Toner 1].

(Example 2)
<Manufacture of toner 2>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A2] was used instead of [Styrene-acrylic resin fine particles A1] in the same manner as in Example 1, [ Toner 2] was prepared.
[Styrene-acrylic resin fine particle A2] used in [Toner 2] is incompatible with [Non-modified Polyester C1] as a binder resin and exhibits a high swellability because it has few cross-linked structures. is there.
Further, when [styrene-acrylic resin fine particles A2] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A2] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 3)
<Manufacture of toner 3>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A3] was used in place of [Styrene-acrylic resin fine particles A1], in the same manner as in Example 1, [3 Toner 3] was prepared.
When [styrene-acrylic resin fine particles A3] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A3] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

Example 4
<Manufacture of toner 4>
In Example 1, as shown in Table 9 below, [Toner 4] of Example 4 was prepared in the same manner as in Example 1 except that [Acrylic resin fine particle B2] was used instead of [Acrylic resin fine particle B1]. Produced.
When [acrylic resin fine particles B2] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Accordingly, it was expected that [acrylic resin fine particles B2] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 5)
<Manufacture of toner 5>
In Example 1, as shown in Table 9 below, [Toner 5] of Example 5 was prepared in the same manner as in Example 1 except that [Acrylic resin fine particle B3] was used instead of [Acrylic resin fine particle B1]. Produced.
When [acrylic resin fine particles B3] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [acrylic resin fine particles B3] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 6)
<Manufacture of toner 6>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A4] was used instead of [Styrene-acrylic resin fine particles A1] in the same manner as in Example 1, except that [ Toner 6] was prepared.
When [Styrene-acrylic resin fine particles A4] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A4] would be dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 7)
<Manufacture of toner 7>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A5] was used in place of [Styrene-acrylic resin fine particles A1], and the same procedure as in Example 1 was repeated. Toner 7] was prepared.
When [styrene-acrylic resin fine particles A5] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Accordingly, it was expected that [styrene-acrylic resin fine particles A5] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 8)
<Manufacture of toner 8>
In Example 1, as shown in Table 9 below, [Toner 8] of Example 8 was prepared in the same manner as in Example 1 except that [Acrylic resin fine particle B4] was used instead of [Acrylic resin fine particle B1]. Produced.
When [acrylic resin fine particles B4] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [acrylic resin fine particles B4] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

Example 9
<Manufacture of toner 9>
In Example 1, as shown in Table 9 below, [Toner 9] of Example 9 was produced except that [Acrylic resin fine particle B5] was used instead of [Acrylic resin fine particle B1].
When [acrylic resin fine particles B5] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [acrylic resin fine particles B5] would be dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 10)
<Manufacture of Toner 10>
In Example 1, as shown in Table 9 below, [Toner 10] of Example 10 was prepared in the same manner as Example 1, except that [Unmodified Polyester C2] was used instead of [Unmodified Polyester C1]. Produced.

(Example 11)
<Manufacture of toner 11>
In Example 1, as shown in Table 9 below, [Toner 11] of Example 11 was prepared in the same manner as in Example 1 except that [Unmodified Polyester C3] was used instead of [Unmodified Polyester C1]. Produced.

(Example 12)
<Manufacture of toner 12>
In Example 1, as shown in Table 9 below, [Toner 12] of Example 11 was prepared in the same manner as in Example 1 except that [Unmodified Polyester C4] was used instead of [Unmodified Polyester C1]. Produced.

(Example 13)
<Manufacture of toner 13>
In Example 1, as shown in Table 9 below, [Toner 13] of Example 11 was prepared in the same manner as in Example 1 except that [Unmodified Polyester C5] was used instead of [Unmodified Polyester C1]. Produced.

(Example 14)
<Manufacture of toner 14>
In Example 1, as shown in Table 9 below, [Toner 14] of Example 11 was prepared in the same manner as in Example 1 except that [Unmodified Polyester C6] was used instead of [Unmodified Polyester C1]. Produced.

(Example 15)
<Manufacture of toner 15>
In Example 1, as shown in Table 9 below, [Toner 15] of Example 11 was prepared in the same manner as in Example 1 except that [Non-modified polyester C1] was used instead of [Non-modified polyester C1]. Produced.

(Example 16)
<Manufacture of Toner 16>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A6] was used instead of [Styrene-acrylic resin fine particles A1] in the same manner as in Example 1, except that [ Toner 16] was produced.
When [Styrene-acrylic resin fine particles A6] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A6] were dispersed and adhered to the droplets of the toner material component in the toner material emulsification step performed thereafter.

(Example 17)
<Manufacture of toner 17>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A7] was used instead of [Styrene-acrylic resin fine particles A1] in the same manner as in Example 1, except that [ Toner 17] was produced.
When [styrene-acrylic resin fine particles A7] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A7] would be dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 18)
<Manufacture of Toner 18>
In Example 1, as shown in Table 9 below, [Toner 18] of Example 18 was changed in the same manner as in Example 1 except that [Acrylic resin fine particle B6] was used instead of [Acrylic resin fine particle B1]. Produced.
When [acrylic resin fine particles B6] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that the [acrylic resin fine particles B] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 19)
<Manufacture of toner 19>
In Example 1, as shown in Table 9 below, [Toner 19] of Example 19 was changed in the same manner as in Example 1 except that [Acrylic resin fine particle B7] was used instead of [Acrylic resin fine particle B1]. Produced.
When [Acrylic resin fine particles B7] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Accordingly, it was expected that [acrylic resin fine particles B7] would be dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Example 20)
<Manufacture of toner 20>
In Example 1, except that [styrene-acrylic resin fine particle A6] was used instead of [styrene-acrylic resin fine particle A1], and [acrylic resin fine particle B6] was used instead of [acrylic resin fine particle B1]. In the same manner as in Example 1, [Toner 20] of Example 20 was produced.

(Example 21)
<Manufacture of toner 20>
In Example 1, except that [Styrene-acrylic resin fine particle A7] was used instead of [Styrene-acrylic resin fine particle A1], and [Acrylic resin fine particle B7] was used instead of [Acrylic resin fine particle B1]. [Toner 21] of Example 21 was produced in the same manner as Example 1.

(Example 22)
<Manufacture of toner 22>
In Example 1, except that [Styrene-acrylic resin fine particle A8] was used instead of [Styrene-acrylic resin fine particle A1], and [Acrylic resin fine particle B8] was used instead of [Acrylic resin fine particle B1]. In the same manner as in Example 1, [Toner 22] of Example 22 was produced.
When [styrene-acrylic resin fine particles A8] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A8] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material. The same applies to [Acrylic resin fine particles B8].

(Example 23)
<Manufacture of toner 23>
In Example 1, except that [styrene-acrylic resin fine particle A9] was used instead of [styrene-acrylic resin fine particle A1], and [acrylic resin fine particle B9] was used instead of [acrylic resin fine particle B1]. In the same manner as in Example 1, [Toner 23] of Example 23 was produced.
When [styrene-acrylic resin fine particles A9] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A9] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material. The same applies to [Acrylic resin fine particles B9].

(Comparative Example 1)
<Manufacture of toner A>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A10] was used in place of [Styrene-acrylic resin fine particles A1], in the same manner as in Example 1, [Comparative Example 1 [ Toner A] was prepared.
When [styrene-acrylic resin fine particles A10] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A10] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Comparative Example 2)
<Manufacture of toner B>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A11] was used in place of [Styrene-acrylic resin fine particles A1], in the same manner as in Example 1, [Comparative Example 1 [ Toner B] was prepared.
When [styrene-acrylic resin fine particles A11] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [styrene-acrylic resin fine particles A11] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Comparative Example 3)
<Manufacture of toner C>
In Example 1, as shown in Table 9 below, [Toner C] of Comparative Example 3 was prepared in the same manner as in Example 1 except that [Acrylic resin fine particle B10] was used instead of [Acrylic resin fine particle B1]. Produced.
When [acrylic resin fine particles B10] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [acrylic resin fine particles B10] would be dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Comparative Example 4)
<Manufacture of toner D>
In Example 1, as shown in Table 9 below, [Toner D] of Comparative Example 4 was prepared in the same manner as in Example 1 except that [Acrylic resin fine particle B11] was used instead of [Acrylic resin fine particle B1]. Produced.
In addition, when [acrylic resin fine particles B11] was added to the aqueous medium phase and observed with an optical microscope, an aggregate of several hundred μm was observed. When this aqueous medium phase was stirred at 8,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, it was expected that [acrylic resin fine particles B11] were dispersed and adhered to the droplets of the toner material component in the subsequent emulsification step of the toner material.

(Comparative Example 5)
<Manufacture of toner E>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particles A10] are used instead of [Styrene-acrylic resin fine particles A1], and [Acrylic resin fine particles B10] are used instead of [Acrylic resin fine particles B1]. [Toner E] of Comparative Example 5 was produced in the same manner as Example 1 except that was used.

(Comparative Example 6)
<Manufacture of toner F>
In Example 1, as shown in Table 9 below, [Styrene-acrylic resin fine particle A11] is used instead of [Styrene-acrylic resin fine particle A1], and [Acrylic resin fine particle B11] is used instead of [Acrylic resin fine particle B1]. [Toner F] of Comparative Example 5 was produced in the same manner as Example 1 except that was used.

<Creation of carrier>
Next, a specific example of manufacturing the carrier used for the actual toner evaluation will be described. The carrier used in the present invention is not limited to these examples.
Carrier raw material composition:
Acrylic resin solution (solid content 50% by mass) 21.0 parts Guanamin solution (solid content 70% by mass) 6.4 parts Alumina particles [0.3 μm, specific resistance 10 ¹⁴ (Ω · cm)] 7.6 parts Silicone resin Solution 65.0 parts [Solid content 23% by mass (SR2410: manufactured by Toray Dow Corning Silicone)]
Minosilane 1.0 part [solid content 100% by mass (SH6020: manufactured by Toray Dow Corning Silicone)]
Toluene 60 parts Butyl cellosolve 60 parts The carrier raw material was dispersed with a homomixer for 10 minutes to obtain a coating film forming solution of acrylic resin and silicone resin containing alumina particles. Firing ferrite powder [(MgO) _1.8 (MnO) _49.5 (Fe ₂ O ₃ ) _48.0 ; volume average particle size: 25 μm] as the core material is coated with the coating film forming solution on the surface of the core material. The coated ferrite powder was obtained by applying with a Spira coater (Okada Seiko Co., Ltd.) to a thickness of 0.15 μm and drying. The obtained coated ferrite powder was fired in an electric furnace at 150 ° C. for 1 hour. After cooling, the ferrite powder bulk was crushed using a sieve having an aperture of 106 μm to obtain [Carrier]. The measurement of the binder resin film thickness was performed by observing the cross section of the carrier with a transmission electron microscope so that the coating film covering the carrier surface could be observed. In this way, [Carrier] having a weight average particle diameter of 35 μm was produced.

<Preparation of two-component developer>
[Toner 1] to [Toner 23] of Examples 1 to 23 and [Toner A] to [Toner F] and [Carrier] of Comparative Examples 1 to 6 were used. Toner] Uniformly mixed and charged 7 parts by mass using a type of tumbler mixer in which the container rolls and stirs, and the two-component developer 1 to 23 according to the present invention and the comparative two-component developer. Agents A to F were prepared.

<Evaluation of toner>
Next, various properties were evaluated as follows using each of the produced [toners] and [two-component developers]. The results are shown in Tables 9 and 10.

<< Method for Measuring Volume Average Particle Size and Dispersed Particle Size of Dispersoid Particles in Toner Material Liquid >>
The dispersoid particle size and the dispersed particle size distribution of the toner material liquid were measured using “Microtrac UPA-150” (manufactured by Nikkiso Co., Ltd.) and analyzed software “Microtrac Particle Size Analyzer-Ver.10.1.2-”. The analysis was performed using “016EE” (manufactured by Nikkiso Co., Ltd.). Specifically, the toner material liquid and then the solvent used for the toner material liquid preparation were added to a glass 30 ml sample bottle to prepare a 10 mass% dispersion. The obtained dispersion was subjected to a dispersion treatment for 2 minutes with an “ultrasonic wave disperser W-113MK-II” (manufactured by Honda Electronics Co., Ltd.).
After measuring the background with the solvent used for the toner material liquid to be measured, the dispersion was dropped, and the dispersed particle size was measured under the condition that the sample loading value of the measuring device was in the range of 1-10. In this measurement method, it is important to measure under the condition that the sample loading value of the measuring device is in the range of 1 to 10 from the viewpoint of measurement reproducibility of the dispersed particle size. In order to obtain the sample loading value, it is necessary to adjust the dripping amount of the dispersion.
Measurement and analysis conditions were set as follows.
Distribution display: Volume, particle size classification selection: standard, number of channels: 44, measurement time: 60 seconds, number of measurements: once, particle permeability: transmission, particle refractive index: 1.5, particle shape: non-spherical, density : 1 g / cm ³ .
The value of the solvent refractive index used was the value of the solvent used in the toner material liquid among the values described in “Guidelines on Input Conditions at Measurement” published by Nikkiso Co., Ltd. The results are shown in Table 9.

<< Average circularity of toner >>
The average circularity of the toner is defined by the following formula (2).
Average circularity SR =
(Perimeter length of a circle having the same area as the particle projection area / perimeter length of the particle projection image) × 100%
... Formula (2)
The average circularity of the toner is measured using a flow type particle image analyzer (“FPIA-3000”; manufactured by Sysmex Corporation), and analyzed using analysis software (FPIA-3000 FLOW PARTIC IMAGE ANALYZER version 00-11). It was. Specifically, 0.1% to 0.5 ml of 10% by mass surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku Co., Ltd.) is added to a glass 100 ml beaker, and each toner 0.1 g to 0.5 g was added and stirred with microspatel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The density of the dispersion was adjusted to 5,000 / μl to 15,000 / μl using the FPIA-3000, and the average circularity of the toner was measured. The results are shown in Table 9.

<< BET specific surface area of toner >>
The BET specific surface area of the toner was measured using an automatic specific surface area / pore distribution measuring device TriStar 3000 (manufactured by Shimadzu Corporation). 1 g of toner was put into a dedicated cell, and degassing treatment was performed in the dedicated cell using a TriStar degassing dedicated unit, Bacuprep 061 (manufactured by Shimadzu Corporation). The deaeration treatment was performed at room temperature, and was performed under reduced pressure conditions of at least 13.33 Pa (100 mtorr) or less for 20 hours. The dedicated cell that has been deaerated can automatically obtain the BET specific surface area using TriStar 3000. Note that nitrogen gas was used as the adsorption gas. The results are shown in Table 9.

<< Transfer efficiency (%) >>
Using an evaluation machine modified from Fuji Xerox DocuColor 8000 Digital Press and tuned to a linear speed of 162 mm / sec and a transfer time of 40 msec, for each [two-component developer], an A4 size, a toner adhesion amount of 0. A running test for outputting a solid pattern of 6 mg / cm ² as a test image was performed. At the initial stage of the test image and after 100K output, the transfer efficiency in the primary transfer was calculated from the following formula (3), and the transfer efficiency in the secondary transfer was calculated from the following formula (4). The evaluation criteria are as follows.
Primary transfer efficiency (%) = (amount of toner transferred onto intermediate transfer member / amount of toner developed on electrophotographic photosensitive member) × 100 Formula (3)
Secondary transfer efficiency (%) = (amount of toner transferred onto the intermediate transfer member−amount of residual toner on the intermediate transfer member / amount of toner transferred onto the intermediate transfer member) × 100 (4)
As the evaluation criteria, an average value of the primary transfer rate and the secondary transfer rate was calculated and evaluated according to the following criteria. The results are shown in Table 10.
〔Evaluation criteria〕
◎: 90% or more ○: 85% or more and less than 90% △: 80% or more and less than 85% ×: less than 80%

<< Fixing temperature limit >>
The fixing unit of the Ricoh full-color MFP Imagio NeoC600Pro has been modified so that the temperature and linear speed can be adjusted, using plain and cardboard transfer paper (type 6000 <70W> made by Ricoh and copy printing Fixation was evaluated with a solid image on paper <135>) with a toner adhesion amount of 0.85 ± 0.1 mg / cm ² . The fixing roll temperature at which the residual ratio of the image density after rubbing the fixed image with a pad becomes 70% or more was determined as the minimum fixing temperature. The results are shown in Table 10.
〔Evaluation criteria〕
◎: Less than 120 ° C ○: Less than 140 ° C 120 ° C or more △: Less than 160 ° C 140 ° C or more ×: 160 ° C or more

<< Upper limit fixing temperature >>
-Hot offset generation temperature-
Using a fixing device in which the fixing unit of the full color multifunctional printer Imagio NeoC600Pro manufactured by Ricoh is remodeled so that the temperature and the linear velocity can be adjusted, the solid paper has a solid image of 0.85 ± 0.3 mg / cm ² . The toner was adjusted so as to be developed. The obtained image was fixed by changing the temperature of the heating roller, and the fixing temperature at which hot offset occurs (offset generation temperature) was measured. The results are shown in Table 10.
〔Evaluation criteria〕
◎: 210 ° C or more ○: Less than 210 ° C 190 ° C or more △: Less than 190 ° C 170 ° C or more ×: Less than 170 ° C

<< Image density >>
Using an evaluation machine, after running 150,000 sheets of an image chart with a 50% image area in monochromatic mode, a solid image was output to 6000 paper manufactured by Ricoh, and the image density was measured using XRite (manufactured by X-Rite). Measurements were made. This was performed for four colors alone, and the average was obtained. When this value is less than 1.2, “x”, when it is 1.2 or more and less than 1.4, “△”, when it is 1.4 or more and less than 1.8, “◯”, 1.8 or more and 2 If less than 2, “◎” was assigned.

<< Image Granularity and Sharpness >> Using an evaluator, a photographic image was output in a single color, and the degree of granularity and sharpness was visually evaluated. In order from the best, “◎” is equivalent to offset printing, “○” is slightly worse than offset printing, “△” is much worse than offset printing, “×” is about the same as conventional electrophotographic images (very much Bad).

(About Figure 1)
1 Toner base particle 2 Styrene-acrylic resin fine particle A
3 Acrylic resin fine particles B
(About FIGS. 3 to 8)
500 roller type charging device 501 charging roller 502 core metal 503 conductive rubber layer 505 photoconductor 510 brush type charging device 511 fur brush roller 513 brush unit 514 power source 515 photoconductor 600 developing device 601 developing sleeve 602 power source 603 developing unit 604 photoconductor 605 Toner 760 Induction heating means 710 Heating roller 720 Fixing roller 730 Endless belt-like fixing belt 731 Base 732 Heat generation layer 733 Intermediate layer 734 Release layer 740 Pressure roller 741 Core metal 742 Elastic member 760 Induction heating means 761 Excitation coil 762 Coil guide plate 763 Excitation coil core 764 Excitation coil core support member 770 Recording material 800 Process cartridge 801 Photoconductor 802 Charging means 803 Development means 804 Developer 805 Development means 806 Cleaning means (about FIG. 9)
100 Image forming apparatus 120Bk, 120C, 120M, 120Y Image writing unit 130Bk, 130C, 130M, 130Y Image forming unit 140 Paper feeding unit 215Bk, 215C, 215M, 215Y Charging device 200Bk, 200C, 200M, 200Y Developing device 230Bk, 230C , 230M, 230Y Primary transfer device 300Bk, 300C, 300M, 300Y Cleaning device 220 Intermediate transfer belt 502 Pre-transfer charger (about FIG. 10)
50 Intermediate transfer member 51 Roller 52 Manual feed tray 53 Manual feed path 55 Switching claw 56 Ejection roller 57 Ejection tray 58 Corona charger 59 Charger 60 Cleaning device (cleaning blade)
61 Developing Device 62 Transfer Charging Device 63 Photoconductor Cleaning Device 64 Static Eliminator 70 Static Eliminating Lamp 80 Transfer Roller 90 Cleaning Device 95 Recording Paper 100A, 100B, 100C Image Forming Device 110 Belt Type Fixing Device 120 Tandem Type Developing Device 130 Document Base 142a, 142b paper feed roller 143 paper bank 144 paper feed cassettes 145a, 145b separation roller 146 paper feed path 147 transport roller 148 paper feed path 150 copier main body 200 paper feed table 300 scanner 400 automatic document feeder

Japanese Patent No. 3066943 Japanese Patent No. 4006136 Japanese Patent No. 3640918 Japanese Patent No. 3492748 Japanese Patent No. 4076681 Japanese Patent No. 3692929

Claims (9)

Toner base particles containing at least a polyester resin;
A surface layer containing styrene-acrylic resin fine particles A and acrylic resin fine particles B formed on the toner base particles;
The outermost surface layer formed from the styrene-acrylic resin fine particles A,
The degree of hydrophobicity of the styrene-acrylic resin fine particles A is 60 to 80%, the degree of hydrophobicity of the acrylic resin fine particles B is 70 to 90% , and the volume average particle size of the acrylic resin fine particles B is 10 %. Toner having a particle diameter of ˜52 nm .   The toner according to claim 1, wherein the polyester resin has a glass transition temperature (Tg) of 10 to 80 ° C.   The toner according to claim 1 or 2, wherein the Tg of the styrene-acrylic resin fine particles A is 40 to 100 ° C.   4. The toner according to claim 1, wherein the acrylic resin fine particles B have a Tg of 40 to 100 ° C. 5.   The toner according to claim 1, wherein an acid value of the polyester resin is 10 to 50 mg KOH / g.   6. The toner according to claim 1, wherein the acid value of the styrene-acrylic resin fine particles A is 130 to 230 mg KOH / g.   The toner according to claim 1, wherein the acrylic resin fine particles B have an acid value of 0 to 15 mg KOH / g.   The toner according to claim 1, wherein the volume average particle diameter of the styrene-acrylic resin fine particles A is 5 to 50 nm. The toner according to any one of claims 1 to 8, wherein the polyester resin has a weight average molecular weight (Mw) of 1,000 to 200,000.