JP2002351139A - Method for manufacturing electrostatic charge image developing toner and method for forming image by using the toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a spheric or irregular toner which has good productivity, preferable fixing property for an oilless heat roller fixing method and preferable distribution of the particle size and which can form developed images with excellent quality. SOLUTION: In the method for manufacturing an electrostatic charge image developing toner, a resin solution composed of at least a polyester resin and an organic solvent is emulsified in a water-based medium, then the organic solvent is removed to form resin fine particles and then the resin fine particles are aggregated to produce toner particles. In this method, the polyester resin shows the T1/2 temperature in the range from 120 deg.C to 160 deg.C measured by a constant-load extrusion capillary rheometer and has 12 ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn). The 50% volume average particle size of the resin fine particles is in the range from >1 μm to <=6 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image, which is suitably used for an electrophotographic copying machine, a printer, a facsimile or the like, and is also used for a toner jet printer or the like.

[0002]

[Prior art]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a toner for developing an electrostatic image, which is suitably used for an electrophotographic copying machine, a printer, a facsimile and the like, and is also used for a toner jet printer and the like. The present invention relates to an image forming method.

[0003]

2. Description of the Related Art In recent years, in electrophotographic copiers, printers, and fax machines, toners have been used to further improve the quality of printed images or to reduce machine cost, downsizing, power saving, and resource saving. The following needs are increasing. (1) Smaller toner particle size for improving the resolution and gradation of printed images, thinning the toner layer, reducing the amount of waste toner, reducing the amount of toner consumed per page, etc. Lowering the fixing temperature to reduce power consumption (3) Oil-less fixing for simplification of machines, etc. (4) Improvement of hue, transparency and gloss in full-color images (5) Adverse effects on human health VOC (volatile organic compound) reduction at the time of fixing, which may give rise to such problems.

[0004] Even a powder toner obtained by a pulverization method which has been used for a long time can basically reduce the particle size.
As the particle size decreases, the ratio of a release agent such as a colorant or wax exposed on the surface of the toner particles increases, so that charge control becomes difficult. Due to the irregular shape of the toner particles, powder fluidity deteriorates. In addition, problems such as an increase in the energy cost required for production occur, and it is practically difficult to sufficiently satisfy the above-mentioned needs with the toner obtained by the pulverization method.

[0005] From such a background, conventionally, a toner by a polymerization method or an emulsion dispersion method (hereinafter referred to as a chemical toner).
Has been actively developed. Various methods are known for the toner obtained by the polymerization method. Among them, among them, a monomer, a polymerization initiator, a colorant, a charge control agent, and the like are added to an aqueous medium containing a dispersion stabilizer while stirring to obtain oil droplets. A suspension polymerization method for forming toner particles and then performing a polymerization reaction by raising the temperature to obtain toner particles is widely known. Alternatively, an association method has been proposed in which fine particles are formed by emulsion polymerization or suspension polymerization, the fine particles are aggregated, and the aggregated fine particles are fused to obtain toner particles. However, in such a polymerization method or an association method using fine particles produced by the polymerization method, although there is no problem in reducing the particle diameter of the toner particles, the main component of the binder resin is limited to a vinyl polymer capable of radical polymerization. Therefore, it is not possible to produce a toner using a polyester resin or an epoxy resin suitable for a color toner or the like. In the polymerization method,
There is also a problem that it is difficult to reduce VOCs (volatile organic compounds composed of unreacted monomers and the like), and improvement is desired.

On the other hand, a method for producing a toner by the emulsification dispersion method is as follows.
JP-A-5-66600 and JP-A-8-21655
As disclosed in Japanese Unexamined Patent Application Publication No. H10-163, a method in which a mixture of a binder resin and a colorant and the like is mixed with an aqueous medium and emulsified to obtain toner particles. In addition to easily adapting to diameter and spheroidization, the range of choice of binder resin is wider than that of the polymerization method, it is easy to reduce residual monomer, and the concentration of colorants etc. from low to high concentration It has the advantage that it can be changed arbitrarily.

As the binder resin for the toner, which has a relatively low fixing temperature and easily melts sharply at the time of fixing to make the image surface smooth, a polyester resin is preferable to a styrene-acrylic resin. Is preferably a polyester resin having excellent flexibility. However, as described above, the polymerization method cannot produce toner particles containing a polyester resin as a main component of the binder resin. Therefore, in recent years, attention has been focused on producing a small particle size toner using a polyester resin as a binder resin by an emulsion dispersion method.

However, in each of the publications for producing toners by the above-described emulsification and dispersion method, the lowering of the fixing temperature and the broadening of the anti-offset temperature range are not always sufficiently realized. In the method for producing a toner by the method, generation of fine particles is inevitable and emulsification loss occurs, so that the yield of the toner is reduced and productivity is deteriorated.

As a production method for solving such a problem, for example, in JP-A-10-020552 and JP-A-11-007156, after emulsifying and dispersing using a polyester resin as a binder resin, A method of producing toner particles by aggregating the obtained fine particles and further fusing them is proposed. According to such a production method, it is considered that there is no generation of ultrafine particles, and therefore, there is no emulsification loss, and it is possible to produce a classification-free toner having a sharp particle size distribution. Mainly low-viscosity, fixing performance at low temperature is improved, but inferior in offset resistance at high temperature, especially lack of oil-less heat roll fixing recently desired .

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to bind a polyester resin having no emulsification loss, a high yield, and a sharp particle size distribution. It is an object of the present invention to provide a novel production method for producing a resinous chemical toner. Another object of the present invention is to produce a novel chemical toner suitable for a so-called oilless fixing method, which has a good fixing / offset temperature range without using an offset prevention liquid, as a toner used in a heat roll fixing method. It is to provide a method. Another object of the present invention is to provide an image forming method using the electrostatic image developing toner obtained by the manufacturing method which solves the above-mentioned problems.

[0011]

Means for Solving the Problems The present inventors have focused on the outflow starting temperature Tfb, T1 / 2 temperature, and outflow end temperature Tend of a constant load extrusion type capillary rheometer of polyester resin, and as a result of intensive studies. It has been found that by setting these to specific ranges, it is possible to obtain good fixing start temperature and hot offset resistance temperature in the oilless fixing system, and completed the present invention.

That is, in the method for producing a toner for developing an electrostatic image of the present invention, a resin solution comprising at least a polyester resin and an organic solvent is emulsified in an aqueous medium, and then the organic solvent is removed to remove the resin fine particles. Forming, further, in a method for producing a toner for electrostatic image development to produce toner particles by aggregating the resin fine particles,
The T1 / 2 temperature of the polyester resin measured by a constant load extrusion type capillary rheometer is in the range of 120 to 160 ° C., and the weight average molecular weight (Mw) and number average molecular weight (Mn)
Wherein the ratio (Mw / Mn) is 12 or more, and the 50% volume average particle diameter of the fine resin particles is more than 1 μm and 6 μm or less. The solution.

Further, the present invention provides a method for forming an electrostatic charge image on an electrostatic image holding member, and using the electrostatic charge image with a developer comprising an electrostatic charge image developing toner carried on a developer carrying member. Developing, transferring the toner image formed on the electrostatic image holding member onto a transfer material, and thermally fixing the toner image on the transfer material with a heat roll to thereby thermally fix the toner image on the transfer material. In an image forming method for forming an image, an image forming method using the electrostatic image developing toner manufactured by the above manufacturing method is provided as a means for solving the above problem.

BEST MODE FOR CARRYING OUT THE INVENTION

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The electrostatic image developing toner of the present invention contains at least a binder and a colorant, and the binder resin is a polyester resin. The polyester resin used as the binder resin is synthesized by dehydrating and condensing a polybasic acid and a polyhydric alcohol.

Examples of the polybasic acid include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, and naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid; Aliphatic carboxylic acids such as alkenylsuccinic anhydride and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid; These polybasic acids can be used alone or in combination of two or more. Among these polybasic acids, it is preferable to use aromatic carboxylic acids.

Examples of the polyhydric alcohol include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin, trimethylolpropane, and pentaerythritol; cyclohexanediol And alicyclic diols such as cyclohexanedimethanol and hydrogenated bisphenol A; and aromatic diols such as ethylene oxide adduct of bisphenol A and propylene oxide adduct of bisphenol A. These polyhydric alcohols can be used alone or in combination of two or more. Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable.

In addition, a monocarboxylic acid and / or a monoalcohol is further added to a polyester resin obtained by polycondensation of a polycarboxylic acid and a polyhydric alcohol,
The hydroxyl value and / or carboxyl group at the polymerization end can be esterified to adjust the acid value of the polyester resin. Examples of the monocarboxylic acid used for such a purpose include acetic acid, acetic anhydride, benzoic acid, trichloroacetic acid, trifluoroacetic acid, and propionic anhydride. Further, as the monoalcohol, for example, methanol, ethanol, propanol, octanol,
Examples include 2-ethylhexanol, trifluoroethanol, trichloroethanol, hexafluoroisopropanol, and phenol.

The polyester resin can be produced by subjecting the above-mentioned polyhydric alcohol and polyvalent carboxylic acid to a condensation reaction according to a conventional method. For example, the polyhydric alcohol and the polyhydric carboxylic acid are blended in a thermometer, a stirrer, a reaction vessel equipped with a falling condenser, and heated at 150 to 250 ° C. in the presence of an inert gas such as nitrogen. By continuously removing low-molecular compounds produced as by-products from the reaction system, stopping the reaction when a predetermined physical property value is reached, and cooling,
The desired reactant can be obtained.

The synthesis of such a polyester resin can be carried out by adding a catalyst. Examples of the esterification catalyst used include organic metals such as dibutyltin dilaurate and dibutyltin oxide, and metal alkoxides such as tetrabutyl titanate. When the carboxylic acid component used is a lower alkyl ester, a transesterification catalyst can be used. Examples of the transesterification catalyst include metal acetates such as zinc acetate, lead acetate and magnesium acetate; metal oxides such as zinc oxide and antimony oxide; and metal alkoxides such as tetrabutyl titanate. The addition amount of the catalyst is preferably in the range of 0.01 to 1% by weight based on the total amount of the raw materials.

In order to produce a branched or crosslinked polyester resin in such a polycondensation reaction, a polybasic acid having three or more carboxyl groups per molecule or an anhydride thereof, and / or A polyhydric alcohol having three or more hydroxyl groups in one molecule may be used as an essential raw material for synthesis.

The polyester resin thus obtained preferably has a value measured by a constant load extrusion type capillary rheometer (hereinafter referred to as a flow tester) in the following range. That is, the outflow starting temperature Tfb by the flow tester is in the range of 80 ° C. to less than 120 ° C., T1
/ 2 Temperature is in the range of 120 ° C to 160 ° C, and outflow end temperature Tend is in the range of 130 ° C to 210 ° C. By using a polyester resin having such a flow tester value, the toner for developing an electrostatic image of the present invention has good oil-less fixability. Further, the glass transition temperature (Tg) is preferably from 40 to 75 ° C.

Outflow starting temperature Tfb by a flow tester,
In the present invention, the T1 / 2 temperature and the outflow end temperature Tend are determined using a flow tester (CFT-500) manufactured by Shimadzu Corporation. As shown in FIG. 1A, this flow tester has a cylinder 2 having a nozzle 1 having a nozzle diameter D of 1.0 mmΦ and a nozzle length (depth) L of 1.0 mm.
Is filled with resin 3 (weight 1.5 g), a load of 10 kg per unit area (cm ² ) is applied from the side opposite to the nozzle 1, and heated at a rate of 6 ° C./min. ,
It is obtained by measuring the stroke S of the load surface 4 (the sink value of the load surface 4). That is, the relationship between the temperature and the stroke S is determined as shown in FIG. 1 (b), and when the flow of the resin 3 from the nozzle 1 starts, the stroke S suddenly increases and the curve rises. Let Tfb be the temperature, and let Tend be the temperature at which the outflow of the resin 3 from the nozzle 1 is almost finished and the curve is bent. The temperature at S1 / 2, which is an intermediate value between the stroke Sfb at Tfb and the stroke Send at Tend, is defined as T1 / 2 temperature.

In the measurement by the temperature raising method using this apparatus, the test is performed while raising the temperature at a constant rate with the passage of the test time, so that the sample is transferred from the solid region to the transition region, to the flow region through the rubbery elastic region. The process leading up to this can be measured continuously. With this device, the shear rate and the viscosity at each temperature in the flow region can be easily measured.

The outflow start temperature Tfb is an index of the sharp melt property and the low-temperature fixability of the polyester resin.
If the temperature is too high, the low-temperature fixability deteriorates, and cold offset easily occurs. Further, if the temperature is too low, the storage stability decreases, and hot offset easily occurs. Therefore, the outflow start temperature Tfb of the toner for developing an electrostatic image of the present invention is more preferably from 90 ° C to 115 ° C, and particularly preferably from 90 ° C to 110 ° C.

Further, the melting temperature T of the toner by the 1/2 method
The 1/2 and the outflow end temperature Tend are indicators of the hot offset resistance. If both are too high, the solution viscosity increases, and the particle size distribution during particle formation deteriorates. In addition, if both are too low in temperature, offset tends to occur and the practicability is reduced. Therefore, 1/2
The melting temperature T1 / 2 by the method needs to be 120 ° C. to 160 ° C., more preferably 130 ° C. to 160 ° C., and the outflow end temperature Tend is preferably 130 ° C. to 210 ° C., and 130 ° C. to 180 ° C. Is more preferred. Tf
By setting b, T1 / 2, and Tend within the above ranges, fixing can be performed in a wide temperature range.

The above-mentioned polyester resin contains a crosslinked polyester resin, and the binder resin has a tetrahydrofuran-insoluble content in the range of 0.1 to 20% by weight, more preferably 0.2 to 10% by weight. Good hot offset resistance can be obtained by using a polyester resin having a tetrahydrofuran-insoluble content of 0.1 to 20% by weight as the binder resin. It can be secured and is preferable. 0.
If it is less than 1% by weight, the effect of improving hot offset resistance is insufficient, which is not preferable. If the content is more than 20% by weight, the solution viscosity becomes too high, the fixing start temperature becomes high, and the balance of fixing property is lost, which is not preferable. Also,
Since the sharp melt property is impaired, the transparency, color reproducibility, and gloss of a color image are poor, which is not preferable.

The tetrahydrofuran-insoluble content of the binder resin was precisely weighed, 1 g of the resin was added to 40 ml of tetrahydrofuran, completely dissolved, and a funnel (diameter) on which Kiriyama filter paper (No. 3) was placed. 2 g of radiolite (# 700, manufactured by Showa Chemical Co., Ltd.) is spread evenly on a 40 mm) and filtered. The cake is placed on an aluminum Petri dish, and then dried at 140 ° C. for 1 hour, and the dry weight is measured. Then, a value obtained by dividing the amount of the residual resin in the dry weight by the amount of the first resin sample is calculated as a percentage, and this value is defined as the insoluble content.

It is more preferable that the binder resin contains a low-viscosity branched or linear polyester resin. That is, in the polyester resin of the present invention, the binder resin may be composed of one kind of polyester resin, but generally, a high molecular weight and high viscosity crosslinked polyester resin (crosslinked polyester resin)
And a low molecular weight, low viscosity, branched or straight-chain polyester resin can be blended and used for the production of the resin, and also to obtain good fixing start temperature and hot offset resistance. And preferred. In the case of blending, the flow tester value of the blended resin may be within the above numerical range. In the present invention, a crosslinked polyester resin refers to a resin having a component insoluble in tetrahydrofuran, and a branched or linear polyester resin refers to a resin in which an insoluble component is not detected in the above-described method for measuring tetrahydrofuran insoluble component.

In the present invention, a plurality of polyester resins having different melt viscosities can be used as the binder resin.
For example, when using a mixture of a low-viscosity branched or linear polyester resin and a crosslinked polyester resin,
It is more preferable to use a mixture of a branched or linear polyester resin (A) and a crosslinked or branched polyester resin (B) under the following conditions. At this time, the melt viscosity and the amount of the resin (A) and the resin (B) are appropriately adjusted so that the flow tester value of the blended resin falls within the above numerical range.

That is, as the polyester resin (A), the T1 / 2 temperature by a flow tester is 80 ° C. or more,
A glass transition temperature Tg of less than 20 ° C.
° C branched or linear polyester resin, and polyester resin (B) as T1 by flow tester
/ 2 A crosslinked or branched polyester resin having a temperature of 120 ° C. or more and 210 ° C. or less and a glass transition temperature Tg of 50 to 75 ° C., and the weight of the polyester resin (A) and the polyester resin (B) The ratio is
(A) / (B) = 20/80 to 80/20, and the T1 / 2 temperatures were set to T1 / 2 (A) and T1 /
When 2 (B) is used, those having a relationship of 20 ° C. <T1 / 2 (B) −T1 / 2 (A) <100 ° C. are preferably used.

Considering each temperature characteristic by the flow tester, the melting temperature T1 / 2 of the resin (A) by the 1/2 method is considered.
(A) is an index for imparting a sharp melt property and a low-temperature fixing property, and T1 / 2 (A) is 80 to 115 ° C.
Is more preferable, and it is particularly preferable that it is in the range of 90 to 110 ° C.

Resin (A) defined by these properties
Has a low softening temperature.In the fixing process using a heat roll, even if the applied heat energy is reduced by lowering the temperature of the heat roll or increasing the process speed, it sufficiently melts and achieves cold offset resistance and low-temperature fixability. Demonstrates excellent performance.

Melting temperature T1 of resin (B) by 1/2 method
/ 2 (B) and the outflow end temperature Tend (B) are both too low, hot offset is likely to occur,
On the other hand, if it is too high, the particle size distribution at the time of particle formation deteriorates and the productivity decreases.
210 ° C., more preferably 130 ° C. to 200 ° C.
C. is particularly preferred.

Resin (B) defined by these properties
Has a strong rubber elasticity and a high melt viscosity, so the internal cohesive force of the melted toner layer is maintained even during heating and melting in the fixing process, hot offset hardly occurs, and its toughness after fixing Demonstrates excellent friction resistance.

By blending the resin (A) and the resin (B) in a well-balanced manner, it is possible to provide a toner that sufficiently satisfies the anti-offset performance and the low-temperature fixing performance in a wide temperature range.

Weight ratio of resin (A) to resin (B) (A)
When / (B) is too small, it affects the fixability,
If it is too large, the offset resistance is affected, so that the ratio is preferably 20/80 to 80/20, and more preferably 30/70 to 70/30.

Also, a half of the resin (A) and the resin (B) is used.
Melting temperature by T1 / 2 (A), T1 / 2
In the case of (B), from the viewpoint of achieving a balance between low-temperature fixability and offset resistance, and in order to facilitate uniform mixing without causing a problem due to a difference in viscosity between resins, T1 / 2 is required.
The range of (B) -T1 / 2 (A) exceeds 20 ° C. and 90 ° C.
The temperature is more preferably not more than 20 and particularly preferably not less than 20 and not more than 80 ° C.

Glass transition temperature (Tg) in the present invention
In the present invention, a differential scanning calorimeter (D
This is a value obtained by using the second run method at a heating rate of 10 ° C. per minute using SC-50).

When the Tg of the polyester resin (A) is less than 40 ° C. or the Tg of the polyester resin (B) is less than 50 ° C., the obtained toner is blocked during storage or in a developing machine (the toner particles are aggregated). Phenomenon
This is not preferable because it is easy to cause a problem. On the other hand, if the Tg of the polyester resin (A) exceeds 70 ° C., or if the Tg of the polyester resin (B) exceeds 75 ° C., the fixing temperature of the toner becomes undesirably high. As described above, by using the polyester resin (A) and the polyester resin (B) having the above relationship as the polyester resin serving as the binder resin, the obtained toner has better fixability, and is preferable. .

The binder resin composed of a polyester resin has a weight average molecular weight of 30,000 or more, preferably 37,000 or more, as determined by gel permeation chromatography (GPC) using a tetrahydrofuran (THF) -soluble component. 000 or more, weight average molecular weight (Mw)
/ The number ratio of components having a number average molecular weight (Mn) of 12 or more, preferably 15 or more, and a molecular weight of 600,000 or more is 0.1% or less.
The area ratio of the component having a molecular weight of 3% or more, preferably 0.5% or more and 10,000 or less is 20 to 80%, preferably 30 to 7%.
It is preferable to satisfy the condition of 0% in order to obtain good fixability. When a plurality of resins are blended, the final GPC measurement result of the resin mixture may fall within the above numerical range.

In the polyester resin used in the production method of the present invention, a high molecular weight component having a molecular weight of 600,000 or more has a function of securing hot offset resistance. On the other hand, a low molecular weight component having a molecular weight of 10,000 or less is effective for lowering the melt viscosity of the resin, developing a sharp melt property and lowering the fixing start temperature, and may contain a resin component having a molecular weight of 10,000 or less. preferable. In order to obtain good thermal characteristics such as low-temperature fixing, hot offset resistance and transparency in the oilless fixing system, it is preferable that the binder resin has such a broad molecular weight distribution. In addition, in granulation of fine particles by an emulsification dispersion method without using a solvent, it is preferable to include a low molecular weight component from the viewpoint of lowering the melt viscosity of the resin.

Here, the molecular weight of the THF-soluble component of the binder resin was determined by filtering the THF-soluble material through a 0.2 μm filter, and then using GPC HLC-8120 manufactured by Tosoh and column “TSKgel SuperHM-M” manufactured by Tosoh. (15cm)
Are used in a THF solvent (flow rate 0.6 ml / min,
At a temperature of 40 ° C.), and the molecular weight was calculated by using a molecular weight calibration curve prepared with a monodispersed polystyrene standard sample.

The acid value of the polyester resin (1 g of resin)
(The number of mg of KOH required to neutralize the toner) is such that the molecular weight distribution as described above is easily obtained, the granulation of fine particles is easily ensured by emulsification and dispersion with no solvent, and the environmental stability of the obtained toner. (Stability of the charging property when the temperature and humidity are changed) is easy to maintain, and the range of 1 to 20 mgKOH / g is preferable. In addition,
As described above, the acid value of the polyester resin may vary depending on the number of raw materials other than adding a monocarboxylic acid and / or a monoalcohol to the polyester resin obtained by polycondensation of a polycarboxylic acid and a polyhydric alcohol. It can be adjusted by controlling the carboxyl group at the terminal of the polyester by the mixing ratio and the reaction rate of the basic acid and the polyhydric alcohol. Alternatively, a polyester having a carboxyl group in the main chain can be formed by using trimellitic anhydride as the polybasic acid component.

In the production method of the present invention, it is preferable to contain a release agent. In this case, the release agent may be a hydrocarbon wax such as polypropylene wax, polyethylene wax, Fischer-Tropsch wax, or a synthetic ester wax. , A wax selected from the group of natural ester waxes such as carnauba wax and rice wax. Specially, it is obtained from natural ester waxes such as carnauba wax and rice wax, polyhydric alcohols and long-chain monocarboxylic acids. If it is less than 1% by weight, the releasability tends to be insufficient, and if it exceeds 40% by weight, the wax tends to be exposed on the surface of the toner particles, and the chargeability and storage stability tend to decrease.

The production method of the present invention preferably contains a charge control agent. The positively chargeable charge control agent is not particularly limited, and a known and commonly used nigrosine dye, a quaternary ammonium compound, an onium compound, a triphenylmethane compound and the like can be used for toner. In addition, compounds containing a basic group such as an amino group, an imino group, or an N-hetero ring, such as a styrene acrylic resin containing a tertiary amino group, also have an effect as a positively chargeable charge controlling agent. The control agent can be used alone or in combination with the positively chargeable charge control agent. Depending on the application, a small amount of a negative charge control agent such as an azo dye metal complex or a salicylic acid derivative metal complex salt may be used in combination with these positively chargeable charge control agents. Examples of the negatively chargeable charge control agent include heavy metals such as trimethylethane dyes, salicylic acid metal complex salts, benzylic acid metal complex salts, copper phthalocyanine, perylene, quinacridone, azo pigments, metal complex salt azo dyes, and azochrome complexes. Acidic dyes, phenol-based condensates of calixarene type, cyclic polysaccharides, resins containing a carboxyl group and / or a sulfonyl group, and the like.

The content of the charge control agent is preferably from 0.01 to 10% by weight. In particular, it is preferably 0.1 to 6% by weight.

The colorant used in the production method of the present invention is not particularly limited, and known and commonly used colorants are used, and pigments are particularly preferably used. As a black pigment,
For example, carbon black, cyanine black, aniline black, ferrite, magnetite and the like can be mentioned. In addition, a mixture of the following chromatic pigments so as to be black can also be used.

As the yellow pigment, for example, graphite, zinc yellow, cadmium yellow, yellow iron oxide, loess, titanium yellow, naphthol yellow S, Hanza yellow 10G, Hanza yellow 5G, Hanza yellow G, Hanza yellow GR, Hanza yellow A, Hansa Yellow RN, Hansa Yellow R, Pigment Yellow L, Benzidine Yellow, Benzidine Yellow G, Benzidine Yellow GR,
Permanent Yellow NCG, Vulcan First Yellow 5G, Vulcan First Yellow R, Quinoline Yellow Lake, Anslagen Yellow 6GL, Permanent Yellow FGL, Permanent Yellow H10G,
Permanent yellow HR, anthrapyrimidine yellow, other isoindolinone yellow, chromophtal yellow, novo palm yellow H2G, condensed azo yellow, nickel azo yellow, copper azomethine yellow and the like.

As the red pigment, for example, red lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, indaslen brilliant orange RK, indaslen brilliant orange GK, benzidine orange G, permanent red 4R, permanent red BL , Permanent red F
5RK, Risor Red, Pyrazolone Red, Watching Red, Lake Red C, Lake Red D, Brilliant Carmine 6B, Brilliant Carmine 3B, Rhodamine Lake B, Alizarin Lake, Permanent Carmine FBB, Verinone Orange, Isoindolinone Orange, Ansuanthrone Orange Pyranthrone orange, quinacridone red, quinacridone magenta, quinacridone scarlet, perylene red and the like.

Examples of the blue pigment include cobalt blue, cerulean blue, alkali blue lake, peacock blue lake, fanatone blue 6G, Victoria blue lake, metal-free phthalocyanine blue, copper phthalocyanine blue, fast sky blue, and induslen blue RS. , Indaslen Blue BC, Indico and the like.

The amount of the colorant used is 100
The range of 1 to 50 parts by weight per part by weight is preferable,
A range of 5 parts by weight is particularly preferred.

Next, the manufacturing method of the present invention will be described. The production method of the present invention comprises the following steps. First step: a step of emulsifying a resin solution containing at least a polyester resin and an organic solvent in an aqueous medium, and thereafter removing the organic solvent to form resin fine particles. Second step: aggregating the resin fine particles, A step of producing an aggregate of the resin fine particles by fusing; a third step: a step of separating and washing the aggregate of the resin fine particles from an aqueous medium, drying and drying to produce a toner (the toner according to the present invention) The aggregate of the resin fine particles produced in the fourth step is dried).

In the first step, the mixture containing at least the polyester resin and the organic solvent is prepared by introducing the polyester resin into the organic solvent and dissolving and dispersing the resin by heating (if necessary). Can be. In this case, as the toner raw material, one or more selected from various colorants, release agents or charge control agents, or other additives can be used together with the polyester resin. In the present invention, it is preferable to disperse the colorant together with the polyester resin in an organic solvent, and it is particularly preferable to dissolve or disperse various additives such as a release agent and a charge control agent.

As a means for dissolving or dispersing the polyester resin and, if necessary, various additives such as a colorant, a release agent and a charge control agent in an organic solvent, the following method is preferably used.

A mixture containing the above-mentioned various additives such as the polyester resin, the colorant, the release agent, and the charge control agent is used by using a pressure kneader, a heated two-roller, a twin-screw extruder or the like. Above the softening point of the polyester resin,
Heat to a temperature below the thermal decomposition temperature and knead. Further, a masterbatch such as a coloring agent and a dilution resin may be melt-kneaded by a twin-screw extruder. Thereafter, the obtained kneaded chips are dissolved or dispersed in an organic solvent using a stirrer such as Despar to prepare. Alternatively, various additives such as a polyester resin and various additives such as a colorant, a release agent, and a charge control agent are mixed with an organic solvent, and the resulting mixture is kneaded and dispersed by a wet method using a ball mill or the like. A resin solution of a polyester resin can be produced. In this case, the colorant and the release agent may be separately preliminarily dispersed and then mixed.

A more specific means of the above method is to dissolve a polyester resin in an organic solvent, add a colorant and a release agent thereto, and use a general medium such as a ball mill, a bead mill, a sand mill, and a continuous bead mill. The mixer used
A master batch was prepared by dispersing using a disperser, and a polyester resin for dilution, an additional organic solvent were mixed, and a colorant or a release agent was finely dispersed in the organic solvent with a stirrer such as a disper. This is a method for producing a resin solution. At this time, rather than directly into a mixing and dispersing machine such as a ball mill without processing the colorant and the release agent, etc., in advance, a low viscosity polyester resin and a colorant, or a release agent etc. in a pressure kneader, It is preferred to use a master batch obtained by kneading and dispersing with a heating two rolls. According to the production method as described above, the polymer component (gel component) of the polyester resin is not cut, and therefore, it is preferable to the method of dispersing by melt-kneading.

Next, as a method of emulsifying a mixture containing a polyester resin and an organic solvent in an aqueous medium, the mixture was adjusted by the above-mentioned method comprising a polyester resin, a coloring agent and the like added as necessary, and an organic solvent. The mixture is preferably mixed with an aqueous medium and emulsified in the presence of a basic neutralizing agent. In this step, a method in which an aqueous medium (water or a liquid medium containing water as a main component) is gradually added to a mixture of a polyester resin, a coloring agent, and an organic solvent is preferable. At that time, by gradually adding water to the organic continuous phase of the mixture, a discontinuous phase of Water in Oil is generated,
Further addition of water causes a phase inversion into a discontinuous phase of Oil in Water, thereby forming a suspension / emulsion in which the mixture is suspended as particles (droplets) in an aqueous medium (hereinafter, referred to as a “suspension / emulsion”). This method is called phase inversion emulsification).

The polyester resin used in the present invention is preferably an acidic group-containing polyester resin, and a polyester resin which becomes self-water dispersible by neutralizing the acidic group (hereinafter referred to as a self-water dispersible resin). ) Is preferable. The resin having self-water dispersibility increases hydrophilicity by the acidic group being anionic, and can be stably dispersed in an aqueous medium without using a dispersion stabilizer or a surfactant. Examples of the acidic group include acidic groups such as a carboxyl group, a sulfonic acid group, and a phosphoric acid group. Among them, the carboxyl group is preferable from the viewpoint of the charging characteristics of the toner. Further, the basic substance for neutralization is not particularly limited, for example, sodium hydroxide, potassium hydroxide,
Inorganic bases such as ammonia and organic bases such as diethylamine, triethylamine and isopropylamine are used. Among them, inorganic bases such as ammonia and sodium hydroxide are preferred. In order to stably disperse the colored resin melt in an aqueous medium, fine particles can also be obtained by adding a suspension stabilizer or a surfactant.
However, when used as a toner, the self-water dispersible resin is preferably used because the charging characteristics tend to deteriorate due to the influence of the dispersion stabilizer and the emulsifier.

The aqueous medium used is preferably water, more preferably deionized water.

Examples of the organic solvent for dissolving or dispersing the polyester resin and a coloring agent or a releasing agent to be added as required include pentane, hexane, heptane, benzene, toluene, xylene, cyclohexane, and the like.
Hydrocarbons such as petroleum ether; halogenated hydrocarbons such as methylene chloride, chloroform, dichloroethane, dichloroethylene, trichloroethane, trichloroethylene and carbon tetrachloride; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ethyl acetate and butyl acetate Esters and the like are used. These solvents can be used as a mixture of two or more, but it is preferable to use the same type of solvent alone from the viewpoint of solvent recovery. The organic solvent is preferably one that dissolves the binder resin, has a relatively low toxicity, and has a low boiling point that is easy to remove the solvent in the subsequent step. As such a solvent, methyl ethyl ketone is most preferred.

The method of neutralizing the acidic group (carboxyl group) of the polyester resin with a base is as follows: (1) A polyester resin having an acidic group which has been neutralized in advance is used to prepare a colorant, a release agent, and an organic solvent. Or a method (2) of preparing a mixture containing a binder resin having an acidic group, a colorant, a wax and an organic solvent and then neutralizing the mixture with a base.

The method for emulsifying the polyester resin after neutralizing the acidic group with a base is as follows: (A) a method of emulsifying the mixture by adding the mixture to an aqueous medium; or (B) emulsifying the mixture by an aqueous medium. Is added. The combination of the above (2) and (B) is preferable because the particle size distribution becomes good.

In addition, there is a method in which a basic neutralizing agent is mixed in an aqueous medium, but in order to sharpen the particle size distribution, a neutralization and emulsification method using the above combination is preferable. In the production method of the present invention, a homomixer (Tokusai Kika Kogyo Co., Ltd.) or a slasher (Mitsui Mining Co., Ltd.)
High shear emulsifying and dispersing machines such as Cavitron (Eurotech Co., Ltd.), Microfluidizer (Mizuho Industry Co., Ltd.), Menton-Gaulin Homogenizer (Gaulin Co., Ltd.), Nanomizer (Nanomizer Co., Ltd.), Static Mixer (Noritake Company) A continuous emulsifying and dispersing machine can be used.

However, for example, Japanese Patent Application Laid-Open No. 9-114
Agitator, anchor wing, as disclosed in 135,
Using a turbine blade, a Faudler blade, a full zone blade, a max blend blade, a half moon blade, etc., the stirring blade has a low peripheral speed of 0.2 to 5 m / s, more preferably 0.5 to 4 m / s. A method of dropping water while stirring is preferable.

By performing emulsification and dispersion under such a low shear, the generation of fine powder can be suppressed, and a more preferable uniform particle size distribution can be realized. Further, the low molecular weight component of the polyester resin does not generate fine powder and does not broaden the molecular weight distribution of the toner particles, and does not deteriorate the low-temperature fixability of the toner.

The organic solvent is removed from the fine particles of the polyester resin solution obtained by the above steps by means such as distillation. In the solvent removal step, it is not necessary to completely remove the organic solvent, and it is preferable to remove 60 to 98% of the used organic solvent. Further, it is more preferable to remove 70 to 95%, particularly preferably to remove 80 to 95%. By leaving a part of the organic solvent, the operation of the step of aggregating and fusing the resin fine particles performed in the next second step becomes easy, and particles having a desired particle shape can be produced. For example, it is a spherical agglomerate that has been fused so as not to retain the shape of the agglomerated resin particles, or an irregularly shaped particle that hardly disturbs the shape of the agglomerated resin particles.

When the amount of the organic solvent remaining in the resin fine particles is large, coarse particles tend to be generated at the time of aggregation and fusion, and when the amount of the residual organic solvent is small, the fusion operation requires time, The deposition temperature must be high, and coarse particles are likely to be generated, which is not preferable. The remaining organic solvent is completely removed after the aggregation / fusion step performed in the second step.

The 50% volume average particle diameter of the resin fine particles produced in the first step is in the range of more than 1 μm and 6 μm or less, more preferably more than 1 μm and 4 μm. When the thickness is 1 μm or less, when a coloring agent or a release agent is used, the encapsulation is not sufficiently performed by the polyester resin. When the particle size is large, the particle size of the obtained toner is limited. Therefore, it is necessary to make the particle size smaller than the target particle size.
If it is larger than μm, coarse particles are likely to be generated, which is not preferable. The obtained microparticles were measured using a 15 micron aperture tube with a Multisizer TAII type manufactured by Coulter, USA.

In the second step, the resin fine particles obtained in the first step are aggregated and further fused to form an aggregate of the resin fine particles to form toner particles having a desired particle diameter. In the coagulation / fusion operation, a coagulation / fusion body can be obtained by appropriately controlling the temperature, salt concentration, pH, stirring conditions, and the like.

In the second step of the present invention, for example, when resin particles consisting only of a polyester resin are produced in the above step, a dispersion of a colorant, a dispersion of a charge control agent, a dispersion of a release agent and the like are separately produced. Then, one or more of these dispersions can be added to a slurry in which resin fine particles consisting of only the polyester resin are suspended, and thereafter, an agglomeration / fusion operation can be performed.

Alternatively, even when resin particles comprising a polyester resin and at least one other raw material for a toner, such as a combination of a polyester resin and a colorant, are produced by the above-described steps, the above-mentioned various dispersions are added to the resin particles. Two steps can be performed. By doing so, it is also possible to manufacture the toner while exposing various additives such as an electrification control agent to the surface of the aggregated particles produced in the second step, and to control the surface properties of the toner according to various uses. can do.

The various dispersions used here can be obtained as follows. For example, a nonionic surfactant represented by a polyoxyethylene alkylphenyl ether, an anionic surfactant represented by an alkylbenzene sulfonate, or a cationic surfactant represented by a quaternary ammonium salt is used for each substance. And a surfactant can be added to water and prepared by a mechanical pulverization method using a medium. Alternatively, instead of a surfactant,
Using a self-water dispersible polyester resin, a dispersion can be prepared by the same dispersion means in the presence of a basic neutralizing agent. Also, the coloring pigment, release agent, and charge control agent used here are:
What has been melt-kneaded with a polyester resin in advance may be used. In this case, the degree of exposure of various materials to the particle surface is reduced by the adsorption of the resin, and preferable characteristics in charging characteristics and developing characteristics are provided.

As described above, in the present invention, various embodiments can be taken without departing from the spirit of the invention. Among them, preferred embodiments include the following. Polyester resin and coloring pigment, release agent if necessary,
A method of producing resin fine particles by the first step using the resin solution comprising the charge control agent and performing the aggregation / fusion step, producing the resin fine particles comprising the polyester resin by the first step, A method of separately preparing one or more dispersion liquids and, if necessary, one or more dispersion liquids of a release agent and a charge control agent, and performing a coagulation / fusion step after mixing them; Using a resin solution comprising a mold agent, resin fine particles are produced in the first step, and a dispersion of a colorant and, if necessary, a dispersion of a charge control agent are mixed, and a coagulation / fusion step is performed. Method,

In order to maintain good triboelectric charging performance, it is effective to prevent the colorant and the like from being exposed on the surface of the toner particles, that is, to have a toner structure in which the colorant and the like are included in the toner particles. It is. The deterioration of the chargeability due to the reduction in the particle size of the toner is also caused by the fact that a part of the contained colorant and other additives (such as wax) is exposed on the surface of the toner particles. That is, even if the content (% by weight) of the colorant or the like is the same, the surface area of the toner particles increases due to the reduction in the particle size, and the ratio of the colorant or wax exposed on the surface of the toner particles increases. As a result, the composition of the surface of the toner particles changes greatly, and the frictional charging performance of the toner particles changes greatly, making it difficult to obtain proper charging properties.

It is desirable that the resin fine particles of the present invention contain a coloring agent, a wax, and the like in the binder resin. With such a structure, a good printed image can be obtained. Whether the colorant, the wax, or the like is not exposed on the surface of the toner particles can be easily determined by, for example, observing the cross section of the particles with a TEM (transmission electron microscope). More specifically, a section obtained by embedding the toner particles in a resin and cutting with a microtome is dyed with ruthenium oxide or the like, if necessary, and observed with a TEM. Can be confirmed. Therefore, in order to positively include the colorant and the release agent, the above-described method is preferable.

The resin fine particles formed from the self-water-dispersible resin obtained up to the first step are stably dispersed in the aqueous medium by the action of the electric double layer by the carboxylate. Aggregation can be achieved by adding an acidic substance that breaks the electric double layer or an electrolyte that reduces the electric double layer to an aqueous medium in which resin fine particles are dispersed. Examples of the acidic substance include hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid,
An acid such as oxalic acid is used. Examples of the electrolyte include water-soluble organic and inorganic salts such as sodium sulfate, ammonium sulfate, potassium sulfate, magnesium sulfate, sodium phosphate, sodium dihydrogen phosphate, sodium chloride, potassium chloride, ammonium chloride, calcium chloride, and sodium acetate. Is used. These substances added for coagulation may be used alone or as a mixture of two or more. Further, the fusion can be performed by heating the aqueous medium.

At this time, in order to prevent the aggregates of the resin fine particles generated by the electrolyte or the acidic substance from fusing together to form an aggregate having a target particle diameter or more, typified by hydroxyapatite. An inorganic dispersion stabilizer or a surfactant may be added. As the surfactant, ionic or nonionic surfactants can be used. Among them, nonionic surfactants are preferable. For example, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene Ethylene sorbitan fatty acid esters and the like can be used. These surfactants may be used alone or in combination of two or more. The nonionic surfactant preferably has a cloud point of 40 ° C. or higher.

Stirring is important for promoting uniform coagulation and fusion. For example, a stirring device, an anchor blade, a turbine blade, and the like disclosed in Japanese Patent Application Laid-Open No. 9-114135.
Faudler wing, full zone wing, max blend wing,
A corn wing, a helical wing, a double helical wing, a half moon wing, or the like is appropriately selected and used.

The shape of the aggregate of the resin fine particles obtained in the second step can be changed from an irregular shape to a spherical shape depending on the degree of fusion. For example, if expressed in average circularity,
It is possible to change from 0.85 to 0.99.
The average circularity can be determined by taking an SEM (scanning electron microscope) photograph of the toner particles obtained by drying the aggregate of the colored resin fine particles, and measuring and calculating the photograph. Since it can be easily obtained by using a flow-type particle image analyzer FPIP-1000 manufactured by Toa Medical Electronics Co., Ltd., in the present invention, the value measured by this apparatus is defined as the average circularity.

The toner particles have an average circularity of 0.9.
When the shape is 7 or more, approximately spherical to spherical, powder fluidity and transfer efficiency are improved. When the toner is used as a toner, the above range is preferable.

In the third step, the dispersion liquid of the aggregate of resin fine particles obtained in the second step is passed through a wet vibrating sieve to remove resin particles and other coarse particles and coarse particles.
Alternatively, solid-liquid separation can be performed by a known and commonly used means such as a filter press and a belt filter. Then, the toner particles can be obtained by drying the particles. It is preferable that the toner particles produced by using an emulsifier or a dispersion stabilizer are more thoroughly washed.

As the drying method, any of known and commonly used methods can be adopted. For example, a method of drying under normal pressure or reduced pressure at a temperature at which the toner particles do not fuse or agglomerate, a method of freeze-drying, And the like. Further, a method of simultaneously separating and drying the toner particles from the aqueous medium by using a spray drier or the like may also be used. In particular, a method of agitating and drying the powder under reduced pressure while heating at a temperature at which the toner particles do not thermally fuse or agglomerate, or a flash jet drier that instantaneously dries using a heated drying air flow (Seishin Enterprise) Is more efficient and preferable.

The particle size distribution of the toner obtained by the production method of the present invention is 50% by volume particle size / 50% by number particle size as measured by a Coulter Multisizer TAII type.
25 or less, more preferably 1.20.
It is as follows. When the ratio is 1.25 or less, a good image can be easily obtained, which is preferable. The GSD is preferably 1.30 or less, more preferably 1.25 or less. GSD is measured by Coulter Multisizer TAII type.
It is a value determined by the square root of (16% volume particle size / 84% volume particle size). The smaller the GSD value, the sharper the particle size distribution, and a better image is obtained.

The toner obtained by the production method of the present invention includes
The volume average particle diameter is preferably in the range of 1 to 13 μm from the viewpoint of the obtained image quality and the like, and is preferably 3 to 10 μm.
A thickness of about μm is more preferable because it is easy to obtain matching with a current machine. For color toner,
The volume average particle size is preferably about 3 to 8 μm. When the volume average particle diameter is small, not only the resolution and the gradation are improved, but also the effect that the thickness of the toner layer for forming the printed image is reduced and the toner consumption per page is reduced is preferable.

The dried toner particles can be used as a developer as they are, but a known and commonly used external additive such as inorganic oxide fine particles or organic polymer fine particles is added to the surface of the toner particles as a toner external additive. Is preferred. Hydrophobic silica, inorganic fine particles such as titanium oxide, or organic fine particles are externally added to toner particles to improve physical properties such as fluidity and chargeability when used as a dry developer by an electrostatic printing method. effective. As the type of the external additive, hydrophobic silica or the like treated with various silicone oils is suitably used. Examples include hydrophobic silica treated with dimethyl silicone oil, alkyl-modified silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, fluorine-modified silicone oil, olefin-modified silicone oil, and the like.
The external addition method is processed using a known and commonly used model.

By mixing a carrier with the above toner particles, an electrostatic image developer can be obtained. The developer for developing an electrostatic image of the present invention comprises the toner of the present invention and a magnetic carrier, preferably a magnetic carrier whose surface is coated with a resin.

As the core agent (magnetic carrier) of the carrier used in the present invention, iron powder, magnetite, ferrite and the like used in a general two-component developing system can be used. Among them, the true specific gravity is low, the resistance is high, and the environment is low. Ferrite or magnetite, which has excellent stability and is easy to form into a sphere and has good fluidity, are preferably used. The shape of the core agent can be used without any particular problem, such as spherical or amorphous. The average particle size is generally from 10 to 200 μm, but is preferably from 30 to 110 μm for printing a high-resolution image.

Examples of the coating resin for coating these core agents include polyethylene, polypropylene, polystyrene, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ether polyvinyl ketone, and vinyl chloride. / Vinyl acetate copolymer, styrene / acrylic copolymer, straight silicone resin comprising organosiloxane bond or its modified product, fluororesin, (meth) acrylic resin, polyester, polyurethane, polycarbonate, phenolic resin, amino resin, melamine resin , Benzoguanamine resin, urea resin, amide resin, epoxy resin and the like can be used.

Among these, silicone resin and (meth) acrylic resin are particularly excellent in charge stability and coating strength, and can be more preferably used. Further, the charging characteristics of the developer composed of the toner particles and the carrier can be adjusted by adjusting the coating amount of a coating agent such as silicon, adding a charge control agent, and adding a conductive substance represented by carbon. In other words, the resin-coated carrier used in the present invention is a resin-coated magnetic carrier coated with at least one resin selected from silicon resin and (meth) acrylic resin using ferrite or magnetite as a core agent. It is preferable to add a charge control agent, carbon or the like during coating to adjust charging characteristics.

The method of coating the surface of the carrier core material with the resin is not particularly limited, but a dipping method of dipping in a solution of the coating resin, a spray method of spraying the coating resin solution onto the surface of the carrier core material, or a carrier method. Fluidized bed method in which the carrier is sprayed while being floated by flowing air, a kneader coater method in which a carrier core material and a coating resin solution are mixed in a kneader coater, and a solvent is removed.

The solvent used in the coating resin solution is not particularly limited as long as it dissolves the coating resin. For example, toluene, xylene, acetone, methyl ethyl ketone, tetrahydrofuran, dioxane and the like can be used. The thickness of the coating layer on the carrier surface is usually 0.1
〜3.0 μm.

The carrier preferably used in the present invention, which is coated with a resin, is subjected to a heat treatment as required. In particular, when coated with a resin containing a cross-linking component, the film is reinforced by a heat cross-linking reaction, so that a more durable carrier is preferable.

When the heat treatment is performed, the charge amount when mixed with the toner can be controlled by the temperature condition. Generally, the higher the heating temperature, the higher the charge amount tends to be. Usually, the heat treatment is performed at a temperature of 100 ° C to 300 ° C for 10 minutes to 5 hours.

After the heat treatment, the carriers may adhere to each other, so that stress may be applied to loosen the carrier particles.

The weight ratio between the hydrophobic silica treated with the silicone oil and the resin-coated magnetic carrier is not particularly limited, but is usually 1 to 5 parts by weight of toner particles per 100 parts by weight of the carrier. When the amount is less than 1 part by weight, triboelectric charging becomes advantageous, so that the charge amount increases and the number of differently charged particles decreases, but the transfer amount decreases,
Not preferred. On the other hand, when the content is more than 5% by weight, triboelectric charging becomes insufficient, tending to lower the rise of charging and increasing the number of differently charged particles, which is not preferable.

Further, the toner of the present invention can be used in an ordinary non-magnetic one-component developing type printing device, a two-component developing type printing device, a magnetic one-component developing type printing device, and the like. Further, a non-magnetic one-component developing device or the like having a developer carrying roll and a layer regulating member is used to transfer a frictionally charged powder toner onto a flexible printed circuit board having an electrode having a function of adjusting the amount of toner passing therethrough. It can also be suitably used in a so-called toner-jet type printer or the like, in which an image is formed by directly spraying the paper on the back electrode through the hole. The toner of the present invention forms an electrostatic charge image on a latent image holding member, and develops the obtained electrostatic charge image using a developer carried on a developer carrying member. Transfer the toner image formed on the transfer material such as paper or film,
Printing can be performed by an image forming method in which the toner image on the transfer material is thermally fixed by a heat roll.

It is preferable that the heat roll used here does not use an anti-offset liquid. Further, the release layer of the heat roll preferably contains a tetrafluoroethylene perfluoroalkyl vinyl ether copolymer. If an anti-offset liquid is used, in addition to the problem of maintenance, since silicone oil or the like is transferred to the printing paper or OHP sheet, there is a problem in that writing after printing is hindered and oil stickiness occurs. ,
Preferably, no anti-offset liquid is used. Also,
When the release layer of the heat roll contains the tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, the deterioration of the fixing roll due to fatigue can be prevented, and the life of the fixing device itself can be prolonged. In addition, since the releasability is high, an offset does not occur even without the use of an anti-offset liquid, and good fixing can be achieved.

[0097]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. In addition,
In Examples and Comparative Examples, parts are parts by weight and water is deionized water unless otherwise specified.

(Synthesis Example of Polyester Resin) Trimellitic anhydride (TMA) as a polycarboxylic acid, terephthalic acid (TPA), and isophthalic acid (IP
A), polyoxypropylene (2.4) -2,2-bis (4-hydroxyphenyl) as an aromatic diol
Propane (BPA-PO), polyoxyethylene (2.
4) Using 2,2-bis (4-hydroxyphenyl) propane (BPA-EO) and ethylene glycol (EG) as an aliphatic diol at each molar composition shown in Table 1,
As a polymerization catalyst, tetrabutyl titanate was charged into a separable fresco at 0.3% by weight based on the total amount of monomers, and a thermometer, a stir bar, a condenser, and a nitrogen inlet tube were attached to the upper part of the flask, and a normal pressure nitrogen gas was heated in an electric heating mantle heater. After reacting at 220 ° C. for 15 hours under an air flow, the pressure was sequentially reduced, and the reaction was continued at 10 mmHg. The reaction is ASTM
-Pursuit was performed by the softening point according to E28-517, and when the softening point reached a predetermined temperature, the vacuum was stopped to terminate the reaction. Table 1 shows the composition and physical properties (characteristics) of the synthesized resin.
Shown in

[0099]

[Table 1] >600,000; area ratio of components having a molecular weight of 600,000 or more <10,000; area ratio of components having a molecular weight of 10,000 or less TMA; trimellitic anhydride TPA; terephthalic acid IPA; isophthalic acid BPA-PO; polyoxypropylene (2. 4) -2,
2-bis (4-hydroxyphenyl) propane BPA-EO; polyoxyethylene (2.4) -2,2
-Bis (4-hydroxyphenyl) propane EG; ethylene glycol BA: benzoic acid TMP; trimethylolpropane FT value; flow tester value

In Table 1, "T1 / 2 temperature" means a flow tester (CFT-500) manufactured by Shimadzu Corporation as described above.
Is a value measured using a nozzle diameter of 1.0 mmΦ × 1.0 mm, a load of 10 kg per unit area (cm ² ), and a heating rate of 6 ° C. per minute. The glass transition temperature “Tg” (° C.) is a value obtained by using a differential scanning calorimeter (D
SC-50) at 10 ° C./min by the second run method.
This is a value measured at a heating rate of.

(Example of Preparation of Release Agent Dispersion) Carnauba Wax "Carnauba Wax 1" (imported by Kato Yoko) 50
And 50 parts of a polyester resin (R1 in Table 1) were kneaded with a pressure kneader, and the kneaded product was mixed with 185 of methyl ethyl ketone.
And the mixture was stirred for 6 hours and then taken out. The solid content was adjusted to 20% by weight to obtain a fine dispersion (W1) of a release agent. Polyester resin R in the same manner
Using No. 2, a dispersion liquid (W2) of a release agent was obtained.

(Preparation of Colorant Master Chip and Preparation of Colorant Dispersion) Carbon black and a color pigment were kneaded with a resin at a weight ratio of 50/50 in the composition shown in Table 2 to prepare colorant master chips P1 to P5. Was prepared. The carbon black and the resin were kneaded using a pressure kneader. The color pigment and the resin were kneaded with two rolls. The resulting kneaded materials P2 to P4 were charged into a ball mill together with methyl ethyl ketone so that the solid content was 35 to 50%.
After stirring for 36 hours, the mixture was taken out, the solid content was adjusted to 20% by weight, and P2 to P4 colorant dispersions were obtained.

[0103]

[Table 2] The coloring agents shown in Table 2 are as follows. Carbon: “ELFTEX-8” (manufactured by Cabot) Cyan Pigment: Fast Gen Blue TGR (manufactured by Dainippon Ink and Chemicals, Inc.) Yellow Pigment: Shimla First Yellow 8GR
(Made by Dainippon Ink and Chemicals, Inc.) Magenta pigment: Fast Gen Super Magenta R
(Manufactured by Dainippon Ink and Chemicals, Inc.)

(Preparation of wet kneading mill base) The above-mentioned release agent dispersion, colorant dispersion, diluting resin (additional resin) and methyl ethyl ketone were mixed with a disper, and the solid content was reduced to 55%.
% To prepare mill bases (MB1 to MB9). Table 3 shows the composition of the prepared mill base.

[0105]

[Table 3] >600,000; area ratio of components having a molecular weight of 600,000 or more <10,000; area ratio of components having a molecular weight of 10,000 or less

Table 4 shows the properties of the blend resins used in Table 3.
It was shown to. The resin blend was prepared by blending resin particles having passed through a mesh of 200 at the above-mentioned weight ratio and measuring respective physical property values.

[0107]

[Table 4]

Example 1 545 parts of Millbase MB1, 32 parts of methyl ethyl ketone and 25.8 parts of 1N ammonia water were added to a cylindrical separable flask having a stirring device, and the mixture was sufficiently stirred. Part,
Stirring was further performed to adjust the temperature to 30 ° C. Then
150 parts of deionized water was added dropwise to obtain a fine particle dispersion by phase inversion emulsification. Next, 400 parts of deionized water was added to remove the solvent, and the solid content was finally adjusted to 34%.

235 parts of the obtained resin fine particle dispersion was diluted with deionized water to a solid content of 20%, and 60 parts of a 20% saline solution was added. The mixture was stirred for 30 minutes and agglomerated until it reached a predetermined particle size. Thereafter, 0.6 part of a nonionic emulsifier NL-250 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added, and the mixture was stirred at 65 ° C. for 3 hours to perform fusion. The obtained slurry was subjected to solid-liquid separation and washing by a centrifugal separator, and then dried by a vacuum dryer to obtain toner particles.

Example 2 545 parts of Millbase MB1, 32 parts of methyl ethyl ketone and 25.8 parts of 1N ammonia water were added to a cylindrical separable flask having a stirring device, and the mixture was sufficiently stirred. Part,
Stirring was further performed to adjust the temperature to 30 ° C. Then
150 parts of deionized water was added dropwise to obtain a fine particle dispersion by phase inversion emulsification. Next, 400 parts of deionized water was added to remove the solvent, and finally the solid content was adjusted to 34%.

235 parts of the obtained resin fine particle dispersion was diluted with deionized water to a solid content of 20%, and 60 parts of a 20% saline solution was added. The mixture was stirred for 30 minutes and agglomerated until it reached a predetermined particle size. Thereafter, 0.6 part of a nonionic emulsifier NL-250 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added, and the mixture was stirred at 65 ° C. for 6 hours to perform fusion. The obtained slurry was subjected to solid-liquid separation and washing with a centrifuge, and then dried with a vacuum drier to obtain toner particles. In the same manner, toner particles of Examples 3 to 8 and Comparative Examples 1 to 3 were prepared using MB2 to MB10. Table 5 shows the properties of the obtained toner particles.

Comparative Example 4 545 parts of Millbase MB1, 32 parts of methyl ethyl ketone and 30.0 parts of 1N ammonia water were added to a cylindrical separable flask having a stirring device, and the mixture was sufficiently stirred. Part,
Stirring was further performed to adjust the temperature to 30 ° C. Then
150 parts of deionized water was added dropwise to obtain a fine particle dispersion by phase inversion emulsification. Next, 400 parts of deionized water was added to remove the solvent, and the solid content was finally adjusted to 34%.

235 parts of the obtained resin fine particle dispersion was diluted with deionized water to a solid content of 20%, and 60 parts of 20% saline solution was added. The mixture was stirred for 30 minutes and agglomerated until it reached a predetermined particle size. Thereafter, 0.6 part of nonionic emulsifier NL-250 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added, and the mixture was stirred at 65 ° C. for 6 hours to perform fusion. The obtained slurry was subjected to solid-liquid separation and washing with a centrifuge, and then dried with a vacuum drier to obtain toner particles.

Comparative Example 5 In a cylindrical separable flask having a stirring device, 545 parts of millbase MB1, 107 parts of methyl ethyl ketone, and isopropyl alcohol 27 were added.
After adding 26.1 parts of 1N ammonia water and stirring sufficiently, 160 parts of deionized water was added and further stirred to adjust the temperature to 30 ° C. Then, 150 parts of deionized water was added dropwise to produce a fine particle dispersion by phase inversion emulsification. Next, 400 parts of deionized water was added to remove the solvent, and the solid content was finally adjusted to 34%.

The obtained slurry was subjected to solid-liquid separation and washing with a centrifugal separator, and then dried with a vacuum drier to obtain toner particles.

Comparative Example 6 In a cylindrical separable flask having a stirrer, 545 parts of millbase MB1, 107 parts of methyl ethyl ketone, and isopropyl alcohol 27 were added.
After adding 26.1 parts of 1N ammonia water and stirring sufficiently, 160 parts of deionized water was added and further stirred to adjust the temperature to 30 ° C. Then, 150 parts of deionized water was added dropwise to produce a fine particle dispersion by phase inversion emulsification. Next, 400 parts of deionized water was added to remove the solvent, and the solid content was finally adjusted to 34%.

235 parts of the obtained resin fine particle dispersion was diluted with deionized water to a solid content of 20%, and 60 parts of a 20% saline solution was added. The mixture was stirred for 30 minutes and agglomerated until it reached a predetermined particle size. Thereafter, 0.6 part of nonionic emulsifier NL-250 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added, and the mixture was stirred at 65 ° C. for 6 hours to perform fusion. The obtained slurry was subjected to solid-liquid separation and washing by a centrifugal separator, and then dried by a vacuum dryer to obtain toner particles.

[0118]

[Table 5] * The initial dispersion diameter after phase inversion emulsification in Table 5 was measured with a Multisizer TAII (aperture tube diameter: 15 μm) manufactured by Coulter, USA. * The characteristics of the toner particles in Table 5 are measured by Multisizer TAII (aperture tube diameter: 10
0 μm).

Each of the obtained toner particles was embedded in a resin, cut with a microtome, and cross-section stained with ruthenate tetroxide was observed with a TEM (transmission electron microscope). It was observed that the pigment and the wax were included in the binder resin and were dispersed almost uniformly in the particles. In the toner of Comparative Example 4, it was confirmed that the colorant and the release agent were not completely included, and a part of the toner was exposed on the toner surface.

Then, using a Henschel mixer, 0.5 part of hydrophobic silica and 0.5 part of titanium oxide were externally added to 100 parts of the obtained toner particles, and a powder toner (toner for developing an electrostatic image) was added. I got

[0121]

[Table 6]

With respect to the fixing temperature range, the fixing temperature was determined by a fixing property test described below, and was indicated by the range between the upper limit value and the lower limit value.

(Fixing property test) Using the powder toners of Examples and Comparative Examples, a printing paper was produced at a speed of 90 mm / sec.
Ricoh Imagio DA-250 is fixed by passing it through a heat roll (the surface of the upper heat roll is coated with a tetrafluoroethylene perfluoroalkyl vinyl ether copolymer), and the fixed image is coated with Cellotape (registered trademark). The surface temperature of the heat roll when the ID (image density) after pasting and peeling is 90% or more of the original ID and no occurrence of offset is observed is referred to as “fixing temperature”.
And From the results shown in Table 5, it was confirmed that the examples of the present invention exhibited good fixing start temperature and hot offset resistance under oil-less fixing conditions in which oil was not applied.

(Image Output Test) Further, with respect to the powder toners of Examples and Comparative Examples, images were output using a commercially available copying machine using a non-magnetic two-component developing system and a non-magnetic one-component printer. Table 6 shows the results.

Regarding the OHP permeability, the following OH
It was evaluated by the evaluation method of P definition. (Method of Evaluating OHP Clearness (Color Transparency)) An unfixed image was formed on a OHP sheet using a color toner, and the unfixed image was fixed using a separately prepared fixing tester.
The fixing was performed by passing through a heat roll (oil-less type: coated with a tetrafluoroethylene perfluoroalkylvinyl ether copolymer) of Ricoh Imagio DA-250 at a heat roll temperature of 160 ° C. and a speed of 90 mm / sec. The OHP sheet printed in black was placed on the OHP sheet created in the above procedure, projected on a screen by an overhead projector, and the sharpness of characters was visually evaluated. The evaluation results are shown as “○” when the characters are clearly visible, “△” when the characters are blurred, and “×” when the characters are not distinguishable.

(Evaluation of Heat Resistance Storage Stability) Further, when the heat resistance blocking test at 50 ° C. for 3 days was performed on the toners of the examples, no aggregation was observed in all the toners.

(Measurement of Charge Amount) To measure the charge amount, a developer was prepared by mixing 3/97 of an externally added toner and a ferrite carrier (particle size: 90 μm) coated with silicone resin.
After stirring by a ball mill for 30 minutes, measurement was performed by a blow-off method. Table 6 shows the results.

[0128]

As described above, according to the production method of the present invention, it is possible to provide not only a production method having a small amount of fine powder and excellent productivity but also (1) T1 / T1 by a constant load extrusion type capillary rheometer. (2) The use of a polyester resin having a temperature in the range of 120 to 160 ° C. and (2) a ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of 12 or more results in spherical to irregular shapes. By using the oilless fixing heat roll, a toner having a good fixing start temperature and a hot offset resistance temperature can be obtained. Further, the 50% volume average particle diameter of the resin fine particles after phase inversion emulsification is set to more than 1 μm to 6 μm or less, and this is fused and aggregated to form toner particles, so that high resolution and high gradation printing without fog can be obtained. Thus, a toner for developing an electrostatic image that can be used is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining how to obtain a flow tester value, wherein FIG. 1 (a) is a side sectional view showing an outline of a measuring device,
(B) is a graph for explaining a method of obtaining each flow tester value from a measured value.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takayuki Ito 2-6-16-202 Higashi-Kojiya, Ota-ku, Tokyo (72) Inventor Kenichi Hirabayashi 1-27-1, Osakidai, Sakura-shi, Chiba Prefecture (72) Inventor Amagaya Shinji 1-4-1-604 Minamiurawa, Saitama-shi, Saitama F-term (reference) 2H005 AA01 AA06 AB03 CA08 CA14 EA03 EA05 EA06 EA10 2H033 AA02 AA09 BA25 BA58 BB01 BB04

Claims (11)

[Claims] 1. A resin solution comprising at least a polyester resin and an organic solvent is emulsified in an aqueous medium, and thereafter,
By removing the organic solvent, resin fine particles are formed,
Further, in the method for producing an electrostatic image developing toner in which the resin fine particles are aggregated to produce toner particles, the T1 / 2 temperature of the polyester resin measured by a constant load extrusion type capillary rheometer is in the range of 120 to 160 ° C. Yes, the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (M
w / Mn) is 12 or more, and 50% of the resin fine particles
A method for producing a toner for developing an electrostatic image, wherein the volume average particle diameter is more than 1 μm and 6 μm or less. 2. The electrostatic charge according to claim 1, wherein the polyester resin is a polyester resin containing an acidic group, and the polyester resin is emulsified in an aqueous medium in the presence of a basic neutralizing agent. A method for producing an image developing toner. 3. The toner according to claim 2, wherein the acid group is a carboxyl group, and the acid value of the polyester resin containing the carboxyl group is 1 to 20 KOH mg / g. Production method. 4. The method for producing a toner for developing an electrostatic image according to claim 1, wherein the polyester resin contains a plurality of polyester resins having different T1 / 2 temperatures. 5. The polyester resin has a (A) T1 / 2 temperature of 8 by a constant load extrusion type capillary rheometer.
0 ° C. or higher and lower than 120 ° C., and a glass transition temperature of 40
A linear or branched polyester resin having a temperature in the range of from 70 ° C. to 70 ° C .; (A) / (B) = 2, wherein the weight ratio of the resin (A) to the resin (B) is 2 or more.
0/80 to 80/20, and assuming that the T1 / 2 temperature is T1 / 2 (A) and T1 / 2 (B), respectively, 20 ° C. <T1 / 2 (B) −T1 / 2 (A) < The method for producing a toner for developing an electrostatic image according to claim 1, wherein the relationship is 100 ° C. 6. The method according to claim 1, wherein the resin solution further contains a colorant. 7. The method for producing a toner for developing an electrostatic image according to claim 1, wherein the resin solution further contains a release agent. 8. The method for producing a toner for developing an electrostatic image according to claim 7, wherein said release agent contains a synthetic ester wax and / or a natural ester wax. 9. An electrostatic image is formed on an electrostatic image holding member, and the electrostatic image is developed using a developer composed of an electrostatic image developing toner carried on a developer carrying member. The toner image formed on the electrostatic image holder is transferred onto a transfer material, and the toner image on the transfer material is heat-fixed by a heat roll to form a heat-fixed toner image on the transfer material. An image forming method, comprising using the electrostatic image developing toner manufactured by the manufacturing method according to claim 1. 10. The image forming method according to claim 9, wherein an offset preventing liquid is not used for the heat roll. 11. The image forming method according to claim 10, wherein the release layer of the heat roll contains a tetrafluoroethylene perfluoroalkyl vinyl ether copolymer.