JP2011059591A - Electrophotographic magenta toner and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magenta toner, which is a toner obtained by aqueous granulation using at least a polyester resin as a binder resin, the toner having no uneven distribution of a colorant and having excellent color developing property and charging property. <P>SOLUTION: The magenta toner comprises toner base particles granulated from a suspension liquid, which in turn is prepared by suspending in an aqueous medium, an oil phase containing a toner material comprising at least a binder resin component, a colorant and a release agent in an organic solvent. A naphthol pigment and a dioxazine pigment are used as the colorant, with a mixing ratio of the naphthol pigment to the dioxazine pigment being 99:1 to 80:20. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrophotographic toner, and more particularly to a full-color toner used in an image forming apparatus using a so-called electrophotographic method, such as an electrostatic copying machine or a laser beam printer, and a manufacturing method thereof.

Conventionally, in an electrophotographic apparatus, an electrostatic recording apparatus, or the like, an electric or magnetic latent image is visualized with toner. For example, in electrophotography, an electrostatic charge image (latent image) is formed on a photoreceptor, and then the latent image is developed with toner to form a toner image. The toner image is usually transferred onto a transfer material such as paper and then fixed by a method such as heating. Toner used for electrostatic image development is generally colored particles in which a binder, a colorant, a charge control agent, and other additives are contained in a binder resin. There are chemical manufacturing methods such as suspension polymerization.
In the pulverization method, a colorant, a charge control agent, an offset preventive agent, and the like are melt-mixed and uniformly dispersed in a thermoplastic resin, and the resulting composition is pulverized and classified to produce a toner.
According to the pulverization method, a toner having some excellent characteristics can be produced, but there is a limitation in the selection of the toner material. For example, the composition obtained by melt mixing must be capable of being pulverized and classified by economically usable equipment. From this requirement, the melt-mixed composition must be made sufficiently brittle. For this reason, when the composition is actually pulverized into particles, an object to be pulverized with a wide range of particle size distribution is easily formed, and when trying to obtain a copy image with good resolution and gradation, for example, In addition, fine particles having a particle size of 5 μm or less, particularly 3 μm or less, and coarse particles having a particle size of 20 μm or more must be removed by classification, resulting in a disadvantage that the yield becomes very low. Further, in the pulverization method, it is difficult to uniformly disperse the release agent, the pigment, and the like in the thermoplastic resin. In addition, since the colorant added to the toner is exposed on the surface of the toner base particles obtained through the pulverization step, the toner particle surface is unevenly charged, the toner charge distribution is expanded, and the development characteristics are improved. There is a problem of lowering. Therefore, because of these problems, the kneading and pulverizing method cannot sufficiently meet the demand for high performance.

In recent years, in order to overcome these problems in the pulverization method, a toner production method using a chemical production method such as a suspension polymerization method has been proposed and implemented. A technique for producing a toner for developing an electrostatic latent image by a polymerization method is known. For example, toner particles are obtained by a suspension polymerization method.
However, the toner particles obtained by the chemical production method are spherical and have the disadvantage of poor cleaning properties. Development / transfer with a low image area ratio results in a small amount of residual toner, and poor cleaning does not pose a problem. However, images with a high image area ratio such as photographic images and untransferred images formed due to poor paper feed Toner may be generated on the photoconductor as untransferred toner, and if accumulated, the image may be soiled.
In addition, the charging roller that contacts and charges the photosensitive member is contaminated, and the original charging ability cannot be exhibited. Furthermore, since the resin is polymerized at the same time as the preparation of the toner, the materials used in conventional toners cannot be used in many cases. Even those that can be polymerized using conventional materials may not be able to adequately control the particle size due to the influence of additives such as resins and colorants. There is a problem that is small.

The problem in particular is that polyester resins that have exhibited excellent fixing performance and color suitability by the conventional kneading and grinding method cannot be used basically, so that they can sufficiently cope with downsizing, high speed, colorization, etc. It is a point that cannot be done. For this reason, a method of obtaining irregularly shaped toner particles by associating resin fine particles obtained by an emulsion polymerization method has been disclosed (see Japanese Patent Application Laid-Open No. 63-186253).
However, in the toner particles obtained by the emulsion polymerization method, a large amount of the surfactant remains not only on the surface but also inside the particles even after the water washing step, and the environmental stability of the toner charging is impaired. The amount distribution is widened, resulting in poor soiling of the obtained image. Further, the remaining surfactant contaminates the photoreceptor, the charging roller, the developing roller, etc., and the original charging ability cannot be exhibited. Even in the emulsion polymerization method in which the colorant component is hardly exposed on the surface of the toner particles, the colorant is easily aggregated, so that it is difficult to uniformly add and disperse the colorant in the toner. Therefore, there is a problem in that the charging becomes non-uniform and the stability when used for a long time is lowered. In the case of color output, a slight deterioration in developability and transferability causes a problem in color balance and gradation. Furthermore, since the colorant in the toner is generally hydrophilic and incompatible with the resin, the transmitted light is irregularly reflected at the interface, and the transparency of OHP or the like is hindered. Therefore, if the dispersion of the colorant is poor, there is also a problem that the transparency with OHP deteriorates.

As a toner preparation method for solving these problems, Japanese Patent Application Laid-Open No. 50-120632 of Patent Document 2, Japanese Patent Application Laid-Open No. 63-25664 of Patent Document 3, Japanese Patent Application Laid-Open No. 5-127422, Patent Document Japanese Patent Application Laid-Open No. 8-179556 discloses a so-called dissolution suspension method in which an oily component liquid in which a toner component is dissolved is made into particles in an aqueous medium, and after removing the solvent, it is pulverized.
However, according to the methods described in these publications, the method of producing toner particles in these aqueous media has an advantage that the toner can be easily spheroidized, while the aqueous particles are used to reduce the average particle diameter of the toner. When the mixture of the medium and the oil component is vigorously stirred, the pigment contained in the toner particles during the atomization tends to segregate at the interface between the aqueous medium and the oil component droplets, and the pigment is exposed on the surface of the toner particles. The pigment dispersion becomes non-uniform. In particular, the magenta pigment has a problem that it is easily segregated on the surface of the toner particles because of its structure, compared with the carbon black and the phthalocyanine pigment.

  As a means for improving pigment dispersibility, Japanese Patent Application Laid-Open No. 11-72958 of Patent Document 6 discloses a technique using a polymer dispersant as a pigment dispersant, and the acid value and amine value of the polymer dispersant are determined. By specifying the toner, a toner having excellent offset property, charging property and storage property, and good color developability and OHP permeability is described. However, when a toner is prepared by suspending and granulating in an aqueous system, it is not sufficient to define the acid value and amine value of the polymer dispersant. Aggregation of the pigment occurs during the preparation of the toner, and the color developability of the toner. Transparency after fixing becomes worse.

On the other hand, a technique for adjusting the hue using two or more kinds of pigments for the purpose of improving the color reproducibility is widely performed.
For example, regarding magenta toner, Japanese Patent Application Laid-Open No. 2003-215847 of Patent Document 7 discloses a magenta toner in which a naphthol pigment and a quinacridone pigment are mixed in a ratio of 80:20 to 30:70 as a magenta pigment. The technology is disclosed.
However, in the dissolution suspension method, the reason for the quinacridone pigment is not clear, but it is probably because the hydrophilic group part in the oil phase droplet is exposed to the aqueous phase side and closes to the aqueous phase side during granulation. Segregates on the particle surface. When the colorant is segregated, the colorant tends to agglomerate, resulting in poor color development and affecting the chargeability.

  The object of the present invention has been made in view of the above. That is, it is a toner obtained by water-based granulation using at least a polyester resin as a binder resin, and provides a magenta toner having excellent colorability and chargeability without uneven distribution of colorants.

As a result of intensive studies, the present inventors have used at least a polyester resin component as a binder resin component, a toner obtained by aqueous granulation, using a naphthol pigment and a dioxazine pigment as colorants, It has been found that by setting the mixing ratio of the naphthol pigment and the dioxazine pigment to 99: 1 to 80:20, it is possible to obtain a toner having excellent colorability, hue, and chargeability.
That is, the said subject is solved by the following this invention.
(1) Toner comprising toner base particles granulated from a suspension obtained by suspending in an aqueous medium an oil phase containing at least a binder resin component, a colorant and a release agent in an organic solvent. In which a naphthol pigment and a dioxazine pigment are used as colorants, and the mixing ratio of the naphthol pigment and the dioxazine pigment is 99: 1 to 80:20.
(2) The magenta toner for electrophotography according to claim 1, wherein a masterbatch obtained by previously dispersing the colorant in a resin for a masterbatch is used.
(3) The electrophotographic magenta toner according to item (1) or (2), wherein the colorant is surface-treated with an acidic surface treatment agent.
(4) The electrophotographic magenta toner according to (3), wherein the surface treating agent has an acid value of 3 KOHmg / g or more and 20 KOHmg / g or less.
(5) The resin for masterbatch according to any one of (2) to (4) above, wherein the resin for the master batch has an acid value of 5 KOHmg / g or more and 40 KOHmg / g or less. Magenta toner.
(6) The surface treatment agent and the colorant are previously dispersed in the masterbatch resin, and the dispersion of the resin, the surface treatment agent and the colorant is melt kneading. The magenta toner for electrophotography according to any one of Items (3) to (5).
(7) The magenta toner for electrophotography according to (6), wherein the melting point of the surface treatment agent is lower than the melting point of the resin.
(8) The magenta toner for electrophotography according to (6) or (7), wherein the melting point of the surface treatment agent is 70 ° C. or higher and 110 ° C. or lower.
(9) The magenta for electrophotography according to any one of (1) to (8), wherein the release agent has a viscosity at 90 ° C. of 5 centipoise or more and 50 centipoise or less. toner.
(10) The surface treatment agent and the colorant are previously dispersed in the masterbatch resin, and the dispersion of the masterbatch resin, the release agent, and the colorant is used as a colorant after washing the pigment. The magenta toner for electrophotography according to any one of (6) to (9), wherein a presscake pigment is used.
(11) The dispersion of the masterbatch resin, the surface treatment agent, and the colorant includes melt mixing of the masterbatch resin, the surface treatment agent, and the colorant, and the melt mixing is an open-type melt kneader. The magenta toner for electrophotography according to item (10), wherein:
(12) An oil phase of an organic solvent containing a toner material containing at least a binder resin component, a colorant and a release agent is suspended in droplets in an aqueous medium, and toner base particles are granulated from the droplets. In a toner production method, a naphthol pigment and a dioxazine pigment are used as colorants, and the mixing ratio of the naphthol pigment and the dioxazine pigment is 99: 1 to 80:20. Toner manufacturing method.
(13) The method for producing a magenta toner for electrophotography according to (12), wherein a master batch in which the colorant is dispersed in advance in a resin for the master batch is used.
(14) The method for producing a magenta toner for electrophotography according to item (12) or (13), wherein the colorant is surface-treated with an acidic surface treatment agent.
(15) The electrophotographic magenta toner according to any one of (12) to (14), wherein the surface treatment agent has an acid value of 3 KOHmg / g or more and 20 KOHmg / g or less. Manufacturing method.
(16) The resin for the masterbatch according to any one of (13) to (15), wherein the resin for the master batch has an acid value of 5 KOHmg / g or more and 40 KOHmg / g or less. A method for producing magenta toner.
(17) The method further comprises a step of dispersing the binder resin, the surface treatment agent, and the colorant in advance, and the dispersion step of the binder resin, the surface treatment agent, and the colorant is melt kneading. A method for producing an electrophotographic magenta toner according to any one of Items (14) to (16).
(18) The method for producing an electrophotographic magenta toner as described in (17) above, wherein the melting point of the surface treatment agent is lower than the melting point of the masterbatch resin.
(19) The method for producing a magenta toner for electrophotography according to (17) or (18), wherein the melting point of the surface treating agent is 70 ° C. or higher and 110 ° C. or lower.
(20) The magenta for electrophotography according to any one of (17) to (19), wherein the release agent has a viscosity at 90 ° C. of 5 centipoise or more and 50 centipoise or less. Toner manufacturing method.
(21) The items (17) to (17), wherein the step of predispersing the masterbatch resin, the surface treatment agent and the colorant uses a presscake pigment after pigment washing as the colorant. The method for producing an electrophotographic magenta toner according to any one of Items (20).
(22) Any of the above items (17) to (21), wherein an open-type melt kneader is used in the step of melt-mixing the masterbatch resin, the surface treatment agent, and the colorant. A method for producing a magenta toner for electrophotography according to claim 1.
(23) Item (12) to Item (22), comprising a step of dispersing the binder resin component, a release agent, and a colorant in the organic solvent to form the oil phase. A method for producing an electrophotographic magenta toner according to any one of the above.

According to the present invention, toner base particles granulated from a suspension obtained by suspending an oil phase containing at least a binder resin component, a colorant and a releasing agent in an organic solvent in an organic solvent. In a toner containing a naphthol pigment and a dioxazine pigment as colorants, if the mixing ratio of the naphthol pigment and the dioxazine pigment is 99: 1 to 80:20, the chroma is high and the hue is high. And a magenta toner that is free from soiling during running under high temperature and high humidity.
Further, according to the present invention, by using a master batch in which a colorant is dispersed in advance in a resin for a master batch that becomes a part of a binder resin, the color is high, the hue is excellent, and the temperature is high under high humidity. A magenta toner having no background stains during running can be obtained.
Furthermore, according to the present invention, by treating the colorant with an acidic surface treatment agent, a magenta toner having high saturation, excellent hue, and no background stains during running under high temperature and high humidity can be obtained. .
Furthermore, according to the present invention, the surface treatment agent has an acid value of 3 KOHmg / g or more and 20 KOHmg / g or less, so that it has high saturation, excellent hue, and no stain on running under high temperature and high humidity. A magenta toner is obtained.
Furthermore, according to the present invention, since the resin for the master batch has an acid value of 5 KOHmg / g or more and 40 KOHmg / g or less, the chroma is high, the hue is excellent, and the soiling is caused by running under high temperature and high humidity. Magenta toner can be obtained.
Further, according to the present invention, the step of dispersing the masterbatch resin, the surface treatment agent and the colorant in advance is melt kneading, so that the saturation is high, the hue is excellent, and the running under high temperature and high humidity is possible. A magenta toner having no background stain can be obtained.
Furthermore, according to the present invention, a magenta toner having a high saturation, excellent hue, and no stain on running under high temperature and high humidity can be obtained because the melting point of the surface treatment agent is lower than the melting point of the resin.
Furthermore, according to the present invention, the melting point of the surface treatment agent is 70 ° C. or higher and 110 ° C. or lower, so that a magenta toner having high saturation, excellent hue, and no background stains during running under high temperature and high humidity can be obtained. It is done.
Further, according to the present invention, the release agent has a viscosity at 90 ° C. of not less than 5 centipoise and not more than 50 centipoise, so that it has high saturation, excellent hue, and soiling during running under high temperature and high humidity. Magenta toner can be obtained.
Furthermore, according to the present invention, the step of dispersing the masterbatch resin, the surface treatment agent and the colorant in advance uses a presscake pigment after washing the pigment as the colorant, so that the chroma is high and the hue is excellent. A magenta toner having no background stains during running under high temperature and high humidity can be obtained.
Furthermore, according to the present invention, by using an open-type melt kneader in the step of melt-mixing the masterbatch resin, the surface treatment agent, and the colorant in advance, high saturation, excellent hue, high temperature and high humidity A magenta toner that is free from background stains during running below can be obtained.

Next, the best mode for carrying out the present invention will be described.
As described above, the toner of the present invention is prepared from a suspension obtained by suspending an oil phase containing an toner solvent containing at least a binder resin component, a colorant and a release agent in an organic solvent in an aqueous medium. In a toner including toner base particles that are granulated, a naphthol pigment and a dioxazine pigment are used as colorants, and the mixing ratio of the naphthol pigment and the dioxazine pigment is 99: 1 to 80:20. It is a feature. Naphthol pigments have a relatively good dispersion in the oil phase or resin, and have a high tinting strength among magenta pigments. On the other hand, since the absorption on the short wavelength side is strong, the magenta pigment is strongly yellowish and has a hue close to red, so that the magenta color reproducibility is poor. By adding a dioxazine pigment as its complementary color, it is possible to approach a magenta hue. Dioxazine pigments are also relatively well dispersed in the oil phase or resin, and have high color development. On the other hand, since it has absorption on the long wavelength side, if it is added too much, the saturation of the magenta color is greatly reduced. Therefore, naphthol pigments and dioxazine pigments are used as colorants, and the mixing ratio of naphthol pigments and dioxazine pigments is 99: 1 to 80:20. A magenta toner having the same can be obtained.

The toner of the present invention is characterized by using a master batch in which a colorant is previously dispersed in a master batch resin. By using a masterbatch, when the oil phase of the colorant is dispersed, the shock is alleviated, the colorant is prevented from agglomerating, the dispersibility of the colorant is improved, and a magenta toner having a good hue, color degree, and chargeability is obtained. be able to.
The toner of the present invention is characterized in that the colorant is surface-treated with an acidic surface treatment agent. When the colorant is an acid-treated product, the dispersibility of the colorant in the resin is improved, and a magenta toner having a good hue, coloration degree, and chargeability can be obtained.
The toner of the present invention is characterized in that the acid value of the surface treatment agent is 3 KOHmg / g or more and 20 KOHmg / g or less. When the acid value is 3 KOH mg / g or less, the colorant is not easily dispersed, and when it is 20 KOH mg / g or more, the external environment tends to be affected by the chargeability. For example, charging is reduced under high temperature and high humidity, resulting in background stains and scattering. When the acid value is 3 KOHmg / g or more and 20 KOHmg / g or less, a toner having excellent pigment dispersibility and excellent running performance under high temperature and high humidity can be obtained.
The toner of the present invention is characterized in that the polyester resin has an acid value of 5 KOHmg / g or more and 40 KOHmg / g or less. Since the acid value of the polyester resin contributes to the dispersibility of the pigment, it is difficult to disperse the pigment if it is 5 KOHmg / g or less. On the other hand, it is preferably 40 KOHmg / g or less because it is easily affected by the external environment. When it is 40 KOHmg / g or more, for example, charging is reduced under high temperature and high humidity, and background staining or scattering occurs.
The toner of the present invention is characterized in that the pre-dispersion of the masterbatch resin, the surface treatment agent, and the colorant is melt kneading. Master batches by melt kneading can be effectively dispersed by using a surface treatment agent, and pigment dispersion agents such as steric hindrance do not re-aggregate pigments as in solvent-based dispersions. Therefore, a stable pigment dispersion can be obtained.
The toner of the present invention is characterized in that the melting point of the surface treatment agent is lower than the melting point of the masterbatch resin. If the melting point of the surface treatment agent is higher than the melting point of the masterbatch resin, it cannot be effectively adsorbed on the pigment surface during melt kneading. On the other hand, when the melting point is lower than the melting point of the masterbatch resin, the surface treatment agent is melted at the time of melt-kneading, can be wetted with the pigment and adsorbed on the particle surface, and a great effect on pigment dispersibility can be obtained.
In the toner of the present invention, the surface treatment agent has a melting point of 70 ° C. or higher and 110 ° C. or lower. When the melting point of the surface treatment agent is lower than 70 ° C., the storage stability under high temperature and high humidity is adversely affected, and problems such as solidification of the toner occur. On the other hand, if the melting point is higher than 110 ° C., it is necessary to increase the temperature in order to melt the surface treatment agent during melt kneading, and the viscosity of the masterbatch resin, which becomes part of the binder resin, decreases, giving high shear. Can not do it.
The toner of the present invention is characterized in that the release agent has a viscosity at 90 ° C. of 5 centipoise or more and 50 centipoise or less. When the viscosity of the surface treatment agent is less than 5 centipoise at 90 ° C., the effect of the surface treatment agent exposed on the toner surface adversely affects the storage stability under high temperature and high humidity, causing the toner to solidify. Occurs. On the other hand, when the viscosity of the surface treatment agent exceeds 50 centipoise at 90 ° C., the viscosity is too high, and it is difficult to get wet with the pigment at the time of melting and hardly adsorb on the pigment surface.
The toner of the present invention is characterized in that a press cake pigment after washing with a pigment is used as a colorant in a step of melt-mixing a masterbatch resin, a surface treatment agent, and a colorant in advance. The press cake contains water between the pigment particles, and a toner having excellent pigment dispersibility can be obtained without agglomeration by substituting the resin for master batch during melt kneading.
The toner of the present invention is characterized in that an open type melt kneader is used in a step of melt-mixing a masterbatch resin, a surface treatment agent and a colorant in advance. An open-type melt kneader can release heat generated during shearing, so that it can be kneaded at a relatively low temperature. Since kneading at a low temperature can impart high resilience to the raw material, it is possible to obtain a toner with more excellent pigment dispersibility.

As the binder resin component in the present invention (binder resin and its precursor, including a masterbatch resin), various known resin components for toner can be used, and among them, a polyester resin is preferably used. For example, it can be used in combination with other resin components such as styrene resins and acrylic resins.
From the viewpoint of pigment dispersibility, the polyester resin used in the present invention preferably contains a propylene oxide adduct of bisphenols in an amount of 50 mol% or more based on the diol component used when polymerizing the polyester resin. More preferred is 70 mol% or more, and more preferred is 80 mol% or more. When combined with a polyester resin containing a certain amount of propylene oxide adduct as a diol component and a polymer dispersant which is a polyester derivative having a predetermined acid value and amine value, the pigment dispersibility is excellent, and the color reproducibility of the toner is excellent. improves. The reason for this is not clear, but it is thought that the affinity between the polyester resin and the polymer dispersant is increased and the pigment is stabilized. The polyols and acids other than the propylene oxide adduct of bisphenols can be arbitrarily selected in consideration of the glass transition point, molecular weight, softening point, etc. of the polyester resin. The hydroxyl value and acid value can be arbitrarily adjusted by adding a trivalent or higher polyol or acid. Examples of diol components other than propylene oxide adducts of bisphenols include alkylene glycols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, and 1,6-hexanediol; diethylene glycol Diols having an oxyalkylene group such as triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; alicyclic Diol added with alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide; bisphenol such as bisphenol A, bisphenol F, bisphenol S Nord acids; the bisphenols include ethylene oxide, alkylene oxide adducts of bisphenols such as those obtained by adding alkylene oxides such as butylene oxide. In addition, it is preferable that carbon number of alkylene glycol is 2-12. Among these, alkylene glycols having 2 to 12 carbon atoms or alkylene oxide adducts of bisphenols are preferred, alkylene oxide adducts of bisphenols or alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbons. The mixture of is particularly preferred.

  Also, trihydric or higher polyols can be used, and trihydric or higher polyols include trihydric or higher aliphatic alcohols, trihydric or higher polyphenols, alkylene oxide adducts of trihydric or higher polyphenols, and the like. Can do. Specific examples of the trihydric or higher aliphatic alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol and the like. Specific examples of the trihydric or higher polyphenols include trisphenol PA, phenol novolak, cresol novolak and the like. Specific examples of adducts of trivalent or higher polyphenols with alkylene oxides include those obtained by adding alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to trihydric or higher polyphenols.

  Examples of the acid component (including acid anhydride and acid chloride) include polycarboxylic acid. The polycarboxylic acid can be appropriately selected according to the purpose, and dicarboxylic acid, trivalent or higher carboxylic acid, a mixture of dicarboxylic acid and trivalent or higher carboxylic acid, and the like can be used. And a small amount of a trivalent or higher polycarboxylic acid mixture is preferred. These may be used alone or in combination of two or more.

  Specific examples of the dicarboxylic acid include divalent alkanoic acid, divalent alkenoic acid, and aromatic dicarboxylic acid. Specific examples of the divalent alkanoic acid include succinic acid, adipic acid, sebacic acid and the like. The number of carbon atoms of the divalent alkenoic acid is preferably 4 to 20, and specific examples include maleic acid and fumaric acid. The aromatic dicarboxylic acid preferably has 8 to 20 carbon atoms, and specific examples thereof include phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. Among these, a divalent alkenoic acid having 4 to 20 carbon atoms or an aromatic dicarboxylic acid having 8 to 20 carbon atoms is preferable.

  As the trivalent or higher carboxylic acid, trivalent or higher aromatic carboxylic acid or the like can be used. The carbon number of the trivalent or higher aromatic carboxylic acid is preferably 9 to 20, and specific examples thereof include trimellitic acid and pyromellitic acid. As the polycarboxylic acid, an acid anhydride or lower alkyl ester of any of dicarboxylic acid, trivalent or higher carboxylic acid, and a mixture of dicarboxylic acid and trivalent or higher carboxylic acid can be used. Specific examples of the lower alkyl ester include methyl ester, ethyl ester, isopropyl ester and the like.

  In the case of using a mixture of dicarboxylic acid and trivalent or higher carboxylic acid, the mass ratio of trivalent or higher carboxylic acid to dicarboxylic acid is preferably 0.01 to 10%, more preferably 0.01 to 1%. preferable.

  As for the mixing ratio at the time of polycondensation of the polyol and the polycarboxylic acid, the equivalent ratio of the hydroxyl group of the polyol to the carboxyl group of the polycarboxylic acid is usually preferably 1 to 2, more preferably 1 to 1.5, 1.02-1.3 is particularly preferred.

As a toner colorant, in the present invention, a quinacridone pigment and a dioxazine pigment are used in combination as a magenta pigment.
Examples of naphthol pigments include C.I. I. Pigment red 150, C.I. I. Pigment red 184, C.I. I. Pigment red 269, and the like.
Examples of the dioxazine pigment include C.I. I. And CI Pigment Violet 23.
In addition, the pigment and the surface treatment agent are preferably dispersed in the binder resin in advance before adjusting the oil phase. More preferably, it is melt kneaded and dispersed. Examples of the melt kneader include a uniaxial extrusion kneader, a biaxial extrusion kneader, a twin roll, and a triple roll. More preferably, a continuous open two-roll kneader is used for the purpose of improving the dispersibility of the surface treatment agent and the pigment. This kneading machine has the kneading force of the open roll kneading machine, in which a strong shearing force is applied over the entire kneading part, by making the roll gap on the kneaded product discharge side wider than the roll gap on the raw material charging side. By concentrating on the raw material charging part in the first half and mainly mixing by melting in the second half part, generation of heat of kneading itself can be suppressed, so that the kneading effect is increased. Two rolls arranged close to each other are heated rolls through which a heating medium is passed, and the other roll is a cooling roll through which a cooling medium is passed. Thus, the dispersibility of the release agent and the pigment is improved.

The wax used in the present invention is natural wax such as beeswax derived from animals, whale wax, shellac wax, carnauba wax derived from plants, wood wax, rice bran wax (rice wax), candelilla wax, paraffin wax derived from petroleum, microcrystalline. There are wax, mineral-derived montan wax, ozokerite and the like, and synthetic waxes include Fischer-Tropsch wax, polyethylene wax, oil-based synthetic wax (ester, ketones, amide), hydrogenated wax and the like.
The type is not limited, but a hydrocarbon wax obtained by separating and refining a petroleum distillation distillation fraction from a viewpoint of releasability is preferably modified with a carboxylic acid or the like. This is because paraffin wax has a relatively low temperature and low viscosity, has a low penetration, and can be controlled easily by modifying the acid value.
The melting point of the wax is preferably lower than the melting point of the binder resin from the viewpoint of the releasing effect, and is preferably 70 ° C. or higher and 110 ° C. or lower. In addition, the amount of wax added is preferably 1 to 20 parts by weight, and the acid value is 3 to 20 KOHmg / g, taking into account the release effect, storage stability at high temperature and high humidity, and chargeability. It is preferable that In consideration of the bleedability of the wax so as not to inhibit charging, the viscosity at 90 ° C. is preferably from 5 to 50.
Further, if the addition amount is too small, the releasing effect is small, and if it is too large, it tends to be affected by the environment, so 3 to 10 parts are preferably added.

  In the present invention, a charge control agent is preferably used. The charge control agent can be appropriately selected from known ones according to the purpose. However, since a color tone may change when a colored material is used, it is preferable to use a colorless or nearly white material. Specifically, triphenylmethane dyes, 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 a compound thereof, a fluorosurfactant, a metal salt of salicylic acid, a metal salt of a salicylic acid derivative, and the like. These may be used alone or in combination of two or more.

  Commercially available products may be used as the charge control agent. Examples of commercially available products include quaternary ammonium salt Bontron P-51, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E-84, and phenol. Condensate E-89 (above, Orient Chemical Industry Co., Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium salt copy charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, boron complex LR-147 (manufactured by Nippon Carlit), Quinacridone, azo pigments, other sulfonic acid groups, carboxyl groups, quaternary ammonia Examples thereof include polymers having a functional group such as a salt. The content of the charge control agent in the toner varies depending on the type of the binder resin, the presence or absence of the additive, the dispersion method, etc., and cannot be generally specified, but is 0.1 to 10 mass relative to the binder resin. % Is preferable, and 0.2 to 5% by mass is more preferable. If the content 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 electrostatic attraction with the developing roller increases. However, the fluidity of the developer and the image density may be reduced.

  The weight average molecular weight of the binder resin contained in the oil phase is preferably 1000 to 30000, and more preferably 1500 to 15000. When the weight average molecular weight is less than 1000, the heat resistant storage stability may be lowered. For this reason, it is preferable that content of the component whose weight average molecular weight is less than 1000 is 8-28 mass%. On the other hand, if the weight average molecular weight exceeds 30000, the low-temperature fixability may be lowered.

  The glass transition temperature of the binder resin is usually 30 to 70 ° C, more preferably 35 to 60 ° C, and still more preferably 35 to 55 ° C. When the glass transition temperature is less than 30 ° C., the heat-resistant storage stability of the toner may be lowered, and when it exceeds 70 ° C., the low-temperature fixability may be lowered.

The acid value of the binder resin is preferably 5 KOHmg / g or more and 40 KOHmg / g or less.
Within this range, the dispersibility of the release agent and pigment is improved, and a toner excellent in color development, releasability, storage stability under high temperature and high humidity, and chargeability can be obtained.

  The aqueous medium can be appropriately selected from known ones. Specific examples include water, water-miscible solvents, and mixtures thereof. Among these, water is particularly preferable. Examples of the water-miscible solvent include alcohol, dimethylformamide, tetrahydrofuran, cellosolves, and lower ketones. Examples of the alcohol include methanol, isopropanol, and ethylene glycol. Examples of lower ketones include acetone and methyl ethyl ketone. These may be used alone or in combination of two or more.

  In the present invention, it is preferable that an oil phase containing a toner material containing at least a binder resin and a colorant is dissolved or dispersed in a solvent. The solvent preferably contains an organic solvent. The organic solvent is preferably removed when forming the toner base particles or after forming the toner base particles.

The organic solvent can be appropriately selected according to the purpose, but since the removal is easy, the boiling point is preferably less than 150 ° C. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, And methyl isobutyl ketone. Of these, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, carbon tetrachloride and the like are preferable, and ethyl acetate is particularly preferable. These may be used alone or in combination of two or more.
The amount of the organic solvent used can be appropriately selected according to the purpose, but is preferably 40 to 300 parts by mass, more preferably 60 to 140 parts by mass, and more preferably 80 to 140 parts by mass with respect to 100 parts by mass of the toner material. 120 parts by mass is more preferable.

The toner material can be appropriately selected depending on the purpose, but usually contains at least a binder resin and a colorant, a compound having an active hydrogen group, and a heavy compound having a site capable of reacting with the active hydrogen group-containing compound. It is preferable to further contain a coalescence, and if necessary, other components such as a release agent and a charge control agent may be further contained.
The mixing ratio of the colorant and the organic solvent in the oil phase containing the toner material can be appropriately selected according to the purpose, and is preferably 5:95 to 50:50. When the blending amount of the colorant is less than this range, the amount of the organic solvent is increased during the production of the toner, and the toner production efficiency may be lowered. When the blending amount is larger than this range, the dispersion of the pigment becomes insufficient. There is.

  The content of the pigment in the toner can be appropriately selected according to the purpose, but is usually 3 to 15% by mass, and preferably 5 to 12% by mass. When the content of the colorant is less than 3% by mass, the coloring power of the toner decreases. When the content of the colorant exceeds 15% by mass, the pigment is poorly dispersed in the toner. May be reduced.

When emulsifying or dispersing the toner material in the aqueous medium using the oil phase containing the toner material, the oil phase containing the toner material is preferably dispersed in the aqueous medium while stirring. A known disperser or the like can be appropriately used for the dispersion. Specific examples of the disperser include a low-speed shear disperser, a high-speed shear disperser, a friction disperser, a high-pressure jet disperser, and an ultrasonic disperser. Especially, since the particle diameter of a dispersion (oil drop) can be controlled to 2-20 micrometers, a high-speed shearing disperser is preferable.
When a high-speed shearing disperser is used, conditions such as the number of rotations, dispersion time, dispersion temperature and the like can be appropriately selected according to the purpose. The rotation speed is preferably 1000 to 30000 rpm, more preferably 5000 to 20000 rpm. In the case of a batch system, the dispersion time is preferably 0.1 to 5 minutes, and the dispersion temperature is preferably 0 to 150 ° C. and more preferably 40 to 98 ° C. under pressure. In general, the dispersion is easier when the dispersion temperature is higher.

The method for forming the toner base particles can be appropriately selected from known methods. Specific examples include a method of forming toner base particles using a dissolution suspension method and the like, and a method of forming toner base particles while producing a binder resin. A method of forming toner base particles while producing a resin is preferred. Here, the binder resin is a base material having adhesion to a recording medium such as paper.
A method of forming toner base particles while producing a binder resin is a method in which a toner material contains a compound having an active hydrogen group and a polymer having a site capable of reacting with the active hydrogen group-containing compound in an aqueous medium. In this method, toner particles are formed while a binder resin is formed by reacting a compound having an active hydrogen group with a polymer having a site capable of reacting with the active hydrogen group-containing compound.
The toner thus obtained may further contain other components such as a release agent and a charge control agent that are appropriately selected as necessary.

As the polymer having a site capable of reacting with the active hydrogen group-containing compound, a modified polyester resin that can react with the active hydrogen group-containing compound is preferably used.
The modified polyester resin capable of reacting with a compound having an active hydrogen group is preferably a polyester having an isocyanate group as a polymer having reactivity with the active hydrogen group. In addition, you may form a urethane bond by adding alcohol when making the isocyanate group containing polyester resin and the compound which has an active hydrogen group react. The molar ratio of the urethane bond to the urea bond thus formed (to distinguish it from the urethane bond of the polyester prepolymer having an isocyanate group) is preferably 0 to 9, and preferably 1/4 to 4. Is more preferable, and 2/3 to 7/3 is particularly preferable. If this ratio is greater than 9, the hot offset resistance may decrease.
The compound having an active hydrogen group acts as an elongation agent, a crosslinking agent or the like when a polymer having a site capable of reacting with the active hydrogen group-containing compound undergoes an elongation reaction, a crosslinking reaction, or the like in an aqueous medium. Specific examples of the active hydrogen group include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), amino group, carboxyl group, mercapto group and the like. In addition, an active hydrogen group may be individual, and 2 or more types of mixtures may be sufficient as it.
The compound having an active hydrogen group can be appropriately selected depending on the purpose, but when the polymer having a site capable of reacting with the active hydrogen group-containing compound is a polyester prepolymer having an isocyanate group, the polyester prepolymer is used. Amines are preferred because they can be increased in molecular weight by rapid extension reaction with a polymer, crosslinking reaction, or the like.

The amines can be appropriately selected depending on the purpose, and specific examples include diamines, trivalent or higher amines, amino alcohols, amino mercaptans, amino acids, and those obtained by blocking these amino groups. Diamines and mixtures of diamines and small amounts of trivalent or higher amines are preferred. These may be used alone or in combination of two or more.
Examples of diamines include aromatic diamines, alicyclic diamines, and aliphatic diamines. Specific examples of the aromatic diamine include phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, and the like. Specific examples of the alicyclic diamine include 4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diaminocyclohexane, isophorone diamine and the like. Specific examples of the aliphatic diamine include ethylene diamine, tetramethylene diamine, hexamethylene diamine and the like. Specific examples of the trivalent or higher amine include diethylenetriamine and triethylenetetramine. Specific examples of amino alcohols include ethanolamine and hydroxyethylaniline. Specific examples of amino mercaptans include aminoethyl mercaptan and aminopropyl mercaptan. Specific examples of amino acids include aminopropionic acid and aminocaproic acid. Specific examples of those in which the amino group is blocked include ketimine compounds and oxazolidone compounds obtained by blocking the amino group with ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone.

In addition, a reaction terminator can be used to stop the elongation reaction, the crosslinking reaction, etc. between the compound having an active hydrogen group and the polymer having a site capable of reacting with the active hydrogen group-containing compound. When a reaction terminator is used, the molecular weight of the adhesive base for toner can be controlled within a desired range. Specific examples of the reaction terminator include monoamines such as diethylamine, dibutylamine, butylamine and laurylamine, and ketimine compounds in which these amino groups are blocked.
The ratio of the equivalent of the isocyanate group of the polyester prepolymer to the equivalent of the amino group of the amine is preferably 1/3 to 3, more preferably 1/2 to 2, and particularly preferably 2/3 to 1.5. . If this ratio is less than 1/3, the low-temperature fixability may be lowered. If it exceeds 3, the molecular weight of the urea-modified polyester resin may be lowered, and the hot offset resistance may be lowered.

The polymer having a site capable of reacting with the active hydrogen group-containing compound (hereinafter sometimes referred to as “prepolymer”) can be appropriately selected from known resins and the like, such as polyol resin, polyacrylic resin, polyester Examples thereof include resins, epoxy resins and derivatives thereof. Among them, it is preferable to use a polyester resin in terms of high fluidity and transparency at the time of melting. These may be used alone or in combination of two or more.
Examples of the site capable of reacting with the active hydrogen group-containing compound of the prepolymer include an isocyanate group, an epoxy group, a carboxyl group, and a functional group represented by a chemical structural formula of —COCl. Among them, an isocyanate group is preferable. The prepolymer may have one of such functional groups or two or more kinds.
As a prepolymer, it is easy to adjust the molecular weight of the polymer component, and oilless 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. Since it can ensure, it is preferable to use the polyester resin which has an isocyanate group etc. which can produce | generate a urea bond.

The polyester prepolymer containing an isocyanate group can be appropriately selected depending on the purpose. Specific examples include a reaction product of a polyester resin having an active hydrogen group obtained by polycondensation of a polyol and a polycarboxylic acid, and a polyisocyanate.
The polyol can be appropriately selected according to the purpose, and a diol, a trihydric or higher alcohol, a mixture of a diol and a trihydric or higher alcohol, etc. can be used, but the diol or the diol and a small amount of a trihydric or higher alcohol. Is preferred. These may be used alone or in combination of two or more.

  Specific examples of the diol include alkylene glycols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol; diethylene glycol, triethylene glycol, dipropylene Diols having an oxyalkylene group such as glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; alicyclic diols including ethylene oxide and propylene oxide , With addition of alkylene oxide such as butylene oxide; bisphenols such as bisphenol A, bisphenol F and bisphenol S; bisphenols with ethyleneoxy , Propylene oxide, alkylene oxide adducts of bisphenols such as those obtained by adding alkylene oxides such as butylene oxide. In addition, it is preferable that carbon number of alkylene glycol is 2-12. Among these, alkylene glycols having 2 to 12 carbon atoms or alkylene oxide adducts of bisphenols are preferred, alkylene oxide adducts of bisphenols or alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbons. The mixture of is particularly preferred.

As trihydric or higher alcohols, trihydric or higher aliphatic alcohols, trihydric or higher polyphenols, alkylene oxide adducts of trihydric or higher polyphenols, and the like can be used. Specific examples of the trihydric or higher aliphatic alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol and the like. Specific examples of the trihydric or higher polyphenols include trisphenol PA, phenol novolak, cresol novolak and the like. Specific examples of the alkylene oxide adducts of trihydric or higher polyphenols include those obtained by adding alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to trihydric or higher polyphenols.
When a diol and a trihydric or higher alcohol are mixed and used, the mass ratio of the trihydric or higher alcohol to the diol is preferably 0.01 to 10%, and more preferably 0.01 to 1%.

  The polycarboxylic acid can be appropriately selected according to the purpose, and dicarboxylic acid, trivalent or higher carboxylic acid, a mixture of dicarboxylic acid and trivalent or higher carboxylic acid, and the like can be used. And a small amount of a trivalent or higher polycarboxylic acid mixture is preferred. These may be used alone or in combination of two or more.

  Specific examples of the dicarboxylic acid include divalent alkanoic acid, divalent alkenoic acid, and aromatic dicarboxylic acid. Specific examples of the divalent alkanoic acid include succinic acid, adipic acid, sebacic acid and the like. The number of carbon atoms of the divalent alkenoic acid is preferably 4 to 20, and specific examples include maleic acid and fumaric acid. The aromatic dicarboxylic acid preferably has 8 to 20 carbon atoms, and specific examples thereof include phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. Among these, a divalent alkenoic acid having 4 to 20 carbon atoms or an aromatic dicarboxylic acid having 8 to 20 carbon atoms is preferable.

As the trivalent or higher carboxylic acid, trivalent or higher aromatic carboxylic acid or the like can be used. The carbon number of the trivalent or higher aromatic carboxylic acid is preferably 9 to 20, and specific examples thereof include trimellitic acid and pyromellitic acid. As the polycarboxylic acid, an acid anhydride or lower alkyl ester of any of dicarboxylic acid, trivalent or higher carboxylic acid, and a mixture of dicarboxylic acid and trivalent or higher carboxylic acid can be used. Specific examples of the lower alkyl ester include methyl ester, ethyl ester, isopropyl ester and the like. In the case of using a mixture of dicarboxylic acid and trivalent or higher carboxylic acid, the mass ratio of trivalent or higher carboxylic acid to dicarboxylic acid is preferably 0.01 to 10%, more preferably 0.01 to 1%. preferable.
As for the mixing ratio at the time of polycondensation of the polyol and the polycarboxylic acid, the equivalent ratio of the hydroxyl group of the polyol to the carboxyl group of the polycarboxylic acid is usually preferably 1 to 2, more preferably 1 to 1.5, 1.02-1.3 is particularly preferred.

The content of the structural unit derived from the polyol in the polyester prepolymer having an isocyanate group is preferably 0.5 to 40% by mass, more preferably 1 to 30% by mass, and particularly preferably 2 to 20% by mass. When this content is less than 0.5% by mass, the hot offset resistance is lowered, 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 this case, the low-temperature fixability may be lowered.
Polyisocyanate can be appropriately selected according to the purpose, but aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, araliphatic diisocyanate, isocyanurates, and these are blocked with phenol derivatives, oximes, caprolactam, etc. And the like.

  Specific examples of the aliphatic diisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, methyl 2,6-diisocyanatocaproate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, tetra And methyl hexane diisocyanate. Specific examples of the alicyclic diisocyanate include isophorone diisocyanate and cyclohexylmethane diisocyanate. Specific examples of the aromatic diisocyanate include tolylene diisocyanate, diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, 4,4′-diisocyanatodiphenyl, 4,4′-diisocyanato-3,3′-dimethyldiphenyl. 4,4′-diisocyanato-3-methyldiphenylmethane, 4,4′-diisocyanato-diphenyl ether, and the like. Specific examples of the araliphatic diisocyanate include α, α, α ′, α′-tetramethylxylylene diisocyanate. Specific examples of the isocyanurates include tris (isocyanatoalkyl) isocyanurate, tris (isocyanatocycloalkyl) isocyanurate, and the like. These may be used alone or in combination of two or more.

  When the polyisocyanate and the polyester resin having a hydroxyl group are reacted, the equivalent ratio of the isocyanate group of the polyisocyanate to the hydroxyl group of the polyester resin is usually preferably 1 to 5, more preferably 1.2 to 4, more preferably 1 .5-3 are particularly preferred. When the equivalent ratio exceeds 5, the low-temperature fixability may decrease, and when it is less than 1, the offset resistance may decrease.

  The content of the structural unit derived from polyisocyanate in the polyester prepolymer containing an isocyanate group is preferably 0.5 to 40% by mass, more preferably 1 to 30% by mass, and further 2 to 20% by mass. preferable. When this content is less than 0.5% by mass, the hot offset resistance may be lowered, and when it exceeds 40% by mass, the low-temperature fixability may be lowered.

  The average number of isocyanate groups that the polyester prepolymer has per molecule is preferably 1 or more, more preferably 1.2 to 5, and even more preferably 1.5 to 4. When the average number is less than 1, the molecular weight of the urea-modified polyester resin is lowered, and the hot offset resistance may be lowered.

  The diol component in the oil phase contains propylene oxide adducts of bisphenols in an amount of 50 mol% or more, and the mass ratio of the polyester prepolymer having an isocyanate group to the polyester resin having a specific hydroxyl value and an acid value is 5/95. -25/75 is preferable, and 10 / 90-25 / 75 is more preferable. When the mass ratio is less than 5/95, the hot offset resistance may be lowered, and when it exceeds 25/75, the low-temperature fixability and the glossiness of the image may be lowered.

  Therefore, as a specific example of the adhesive substrate contained in the toner, a polyester prepolymer obtained by reacting a polycondensate of bisphenol A propylene oxide 2 mol adduct and isophthalic acid with isophorone diisocyanate is uread with isophorone diamine. A polyester prepolymer prepared by reacting a polycondensate of bisphenol A propylene oxide 2 mol adduct and isophthalic acid with isophorone diisocyanate with isophorone diamine. Mixture of uread product with bisphenol A propylene oxide 2 mol adduct and terephthalic acid polycondensate; bisphenol A ethylene oxide 2 mol adduct / bisphenol A propylene oxide A polyester prepolymer obtained by reacting a polycondensate of idophthalic acid and a polycondensate of terephthalic acid with isophorone diisocyanate and urealated with isophorone diamine, and a bisphenol A ethylene oxide 2 mole adduct / bisphenol A propylene oxide 2 mole adduct ( Bisphenol A propylene oxide 2 mol adduct mixture ratio is 50 mol% or more) and polycondensate of terephthalic acid; polycondensation of bisphenol A ethylene oxide 2 mol adduct / bisphenol A propylene oxide 2 mol adduct and terephthalic acid A polyester prepolymer obtained by reacting a product with isophorone diisocyanate and uread with isophorone diamine, and a polycondensate of bisphenol A propylene oxide 2 mol adduct and terephthalic acid Compound: Polyester prepolymer obtained by reacting a polycondensate of bisphenol A ethylene oxide 2-mole adduct and terephthalic acid with isophorone diisocyanate, ureated with hexamethylenediamine, bisphenol A propylene oxide 2-mole adduct and terephthalate Mixture with acid polycondensate; bisphenol A ethylene oxide 2 mol adduct and polyester prepolymer obtained by reacting terephthalic acid polycondensate with isophorone diisocyanate and urethanized with hexamethylenediamine, and bisphenol A ethylene oxide 2 Mole adduct / bisphenol A propylene oxide 2 mol adduct (mixing ratio of bisphenol A propylene oxide 2 mol adduct is 50 mol% or more) and polycondensate of terephthalic acid A polyester prepolymer obtained by reacting a polycondensate of bisphenol A ethylene oxide 2 mol adduct and terephthalic acid with isophorone diisocyanate with urea and ethylenediamine, a polycondensate of bisphenol A propylene oxide 2 mol adduct and terephthalic acid A mixture of bisphenol A ethylene oxide 2-mole adduct and a polycondensate of isophthalic acid with diphenylmethane diisocyanate, urealated with hexamethylenediamine, bisphenol A propylene oxide 2-mole adduct and isophthalic acid Mixtures with acid polycondensates; bisphenol A ethylene oxide 2-mole adduct / bisphenol A propylene oxide 2-mole adduct and terephthalic acid / dodecenyl A polyester prepolymer obtained by reacting a polycondensate of an acid anhydride with diphenylmethane diisocyanate and uread with hexamethylenediamine, and a bisphenol A ethylene oxide 2 mol adduct / bisphenol A propylene oxide 2 mol adduct (bisphenol A propylene oxide). 2 mol adduct mixture ratio is 50 mol% or more) and a mixture of terephthalic acid polycondensate; a polyester prepolymer obtained by reacting bisphenol A ethylene oxide 2 mol adduct and isophthalic acid polycondensate with toluene diisocyanate. Mixture of urealated with methylenediamine and bisphenol A propylene oxide 2 mol adduct and isophthalic acid polycondensate: bisphenol A ethylene oxide 2 mol adduct / bisph A polyester prepolymer obtained by reacting a 2-mole adduct of diol A propylene oxide, a polycondensate of terephthalic acid and trimellitic acid with isophorone diisocyanate, and urethanized with a ketimine compound whose amino group is blocked with ketones, and bisphenol A ethylene A mixture of oxide 2 mol adduct / bisphenol A propylene oxide 3 mol adduct (bisphenol A propylene oxide 3 mol adduct mixture ratio is 50 mol% or more) and polycondensate of terephthalic acid, adipic acid, trimellitic acid, etc. Can be mentioned.

The toner of the present invention is usually used by adding an external additive to the base particles. As the external additive, organic fine particles such as PMMA and inorganic particles can be appropriately selected from known materials according to the purpose. Specific examples of the orientation particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, and diatomaceous earth. , Chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride and the like. These may be used alone or in combination of two or more.
The primary particle diameter of the inorganic particles is preferably 5 nm to 2 μm, and more preferably 5 nm to 500 nm. Moreover, it is preferable that the specific surface area by BET method of an inorganic particle is 20-500 m < ² > / g.
The content of inorganic particles in the toner is preferably 0.01 to 5.0% by mass, and more preferably 0.01 to 5.0% by mass. These inorganic particles are used after surface treatment from the viewpoints of improvement in fluidity and blocking property, and preservation and water resistance. Specific examples of the surface treatment include a silane coupling agent, a silylating agent, a silane coupling agent having a fluorinated alkyl group, an organic titanate coupling agent, an aluminum coupling agent, silicone oil, and modified silicone oil. Can be mentioned.

Next, as an example of a toner production method, a method for forming toner base particles while producing an adhesive substrate will be described below. In such a method, preparation of an aqueous medium phase, preparation of an oil phase containing a toner material, emulsification or dispersion of the toner material, formation of an adhesive substrate, removal of the solvent, heavy weight having reactivity with active hydrogen groups. Synthesis of a compound, synthesis of a compound having an active hydrogen group, and the like are performed. The aqueous medium can be prepared by dispersing the resin particles in the aqueous medium. The addition amount of the resin particles in the aqueous medium is preferably 0.5 to 10% by mass.
The oil phase containing the toner material is prepared in a solvent by a compound having an active hydrogen group, a polymer having a site capable of reacting with the active hydrogen group-containing compound, a colorant, a release agent, a charge control agent, and the polyester. A toner material such as a resin can be dissolved or dispersed. In the toner material, components other than the polymer having a site capable of reacting with the active hydrogen group-containing compound, the colorant, and the polyester resin are added and mixed in the aqueous medium when the resin particles are dispersed in the aqueous medium. Alternatively, the oil phase containing the toner material may be added to the aqueous medium when it is added to the aqueous medium.
The emulsification or dispersion of the toner material can be performed by dispersing the oil phase containing the toner material in an aqueous medium. Then, when the toner material is emulsified or dispersed, an adhesive base material is obtained by subjecting a polymer having a site capable of reacting with the active hydrogen group-containing compound and the active hydrogen group-containing compound to an extension reaction and / or a crosslinking reaction. Generate.

Adhesive substrates such as urea-modified polyester-based resins contain, for example, an oil phase containing a polymer having reactivity with active hydrogen groups such as polyester prepolymers having isocyanate groups, and active hydrogen groups such as amines. The oil phase containing the toner material may have an active hydrogen group in advance. The oil phase may be emulsified or dispersed in an aqueous medium together with the compound to be produced, and then both may be subjected to an extension reaction and / or a crosslinking reaction in the aqueous medium. The oil phase containing the toner material may be emulsified or dispersed in an aqueous medium by emulsifying or dispersing it in an aqueous medium to which a compound is added, and subjecting both to an extension reaction and / or a crosslinking reaction in the aqueous medium. Then, a compound having an active hydrogen group is added, and an extension reaction and / or a cross-linking reaction are performed in the aqueous medium from the particle interface. It may be. When both are subjected to an extension reaction and / or a cross-linking reaction from the particle interface, a urea-modified polyester resin is preferentially formed on the surface of the toner to be produced, and a concentration gradient of the urea-modified polyester resin can be provided in the toner.
The reaction conditions for producing the adhesive substrate can be appropriately selected according to the combination of the polymer having a site capable of reacting with the active hydrogen group-containing compound and the compound having an active hydrogen group. The reaction time is preferably 10 minutes to 40 hours, more preferably 2 hours to 24 hours. The reaction temperature is preferably 0 to 150 ° C, more preferably 40 to 98 ° C.

As a method for stably forming a dispersion containing a polymer having a site capable of reacting with an active hydrogen group-containing compound such as a polyester prepolymer having an isocyanate group in an aqueous medium, active hydrogen is added in the aqueous medium phase. An oil phase prepared by dissolving or dispersing a toner material such as a polymer having a site capable of reacting with a group-containing compound, a colorant, a release agent, a charge control agent and the polyester resin in a solvent is added, and shear force is applied. Examples of the method include dispersion.
Dispersion can be performed using a known disperser, and examples of the disperser include a low-speed shear disperser, a high-speed shear disperser, a friction disperser, a high-pressure jet disperser, and an ultrasonic disperser. A high-speed shearing disperser is preferable because the particle diameter of the dispersion can be controlled to 2 to 20 μm.
When a high-speed shearing disperser is used, conditions such as the number of rotations, dispersion time, dispersion temperature and the like can be appropriately selected according to the purpose. The rotation speed is preferably 1000 to 30000 rpm, more preferably 5000 to 20000 rpm. In the case of a batch system, the dispersion time is preferably 0.1 to 5 minutes, and the dispersion temperature is preferably 0 to 150 ° C., more preferably 40 to 98 ° C. under pressure. The dispersion temperature is generally easier to disperse when the temperature is higher.
The amount of the aqueous medium used when emulsifying or dispersing the toner material is preferably 50 to 2000 parts by mass, more preferably 100 to 1000 parts by mass with respect to 100 parts by mass of the toner material. If the amount used is less than 50 parts by mass, the dispersion state of the toner material may be deteriorated, and toner base particles having a predetermined particle diameter may not be obtained. May be.
In the step of emulsifying or dispersing the oil phase containing the toner material, it is preferable to use a dispersant from the viewpoints of stabilizing the dispersion such as oil droplets to obtain a desired shape and sharpening the particle size distribution.
The dispersant can be appropriately selected according to the purpose, and examples thereof include surfactants, sparingly water-soluble inorganic compound dispersants, and polymeric protective colloids, and surfactants are preferred. These may be used alone or in combination of two or more.

  As the surfactant, an anionic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, and the like can be used. Examples of the anionic surfactant include alkylbenzene sulfonate, α-olefin sulfonate, phosphate ester, and the like, and those having a fluoroalkyl group are preferably used. As an anionic surfactant having a fluoroalkyl group, a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms or a metal salt thereof, disodium perfluorooctanesulfonylglutamate, 3- [ω-fluoroalkyl (C6-C11) oxy ] Sodium 1-alkyl (C3-C4) sulfonate, sodium 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonate, fluoroalkyl (C11-C20) carboxylic acid or Its metal salt, perfluoroalkylcarboxylic acid (C7 to C13) or its metal salt, perfluoroalkyl (C4 to C12) sulfonic acid or its metal salt, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- (2 -Hydroxyethyl) perfluorooctance Examples include sulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, and the like. Commercially available surfactants having a fluoroalkyl group include Surflon S-111, S-112, S-113 (manufactured by Asahi Glass Co., Ltd.), Fluorard FC-93, FC-95, FC-98, FC-129. (Above, manufactured by Sumitomo 3M), Unidyne DS-101, DS-102 (above, manufactured by Daikin Industries, Ltd.), MegaFuck F-110, F-120, F-113, F-191, F-812, F- 833 (above, manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (above, manufactured by Tochem Products), Footage 100, 150 (above, manufactured by Neos).

As cationic surfactants, amine salt type surfactants such as alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazoline; alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts And quaternary ammonium salt type surfactants such as alkylisoquinolinium salts and benzethonium chloride. Among them, aliphatic primary, secondary or tertiary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts, benzalkonium salts, benzethonium chloride, Examples include pyridinium salts and imidazolinium salts. Commercially available cationic surfactants include Surflon S-121 (Asahi Glass Co., Ltd.); Florard FC-13
5 (manufactured by Sumitomo 3M); Unidyne DS-202 (manufactured by Daikin Industries, Ltd.), MegaFac F-150, F-824 (manufactured by Dainippon Ink &Co.); Xtop EF-132 (manufactured by Tochem Products); It is preferable to use a footent F-300 (manufactured by Neos).
Examples of nonionic surfactants include fatty acid amide derivatives and polyhydric alcohol derivatives.
Specific examples of the amphoteric surfactant include alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine, N-alkyl-N, N-dimethylammonium betaine and the like.

Specific examples of the hardly water-soluble inorganic compound dispersant include tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite.
Polymeric protective colloids include monomers having carboxyl groups, alkyl (meth) acrylates having hydroxyl groups, vinyl ethers, vinyl carboxylates, amide monomers, acid chloride monomers, monomers having nitrogen atoms or heterocyclic rings thereof, and the like. Examples thereof include homopolymers or copolymers obtained by polymerization, polyoxyethylene resins, and celluloses. In addition, the homopolymer or copolymer obtained by polymerizing the above monomers includes those having a structural unit derived from vinyl alcohol.

  Specific examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride and the like. Specific 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, glycerol monoacrylate, glycerol monomethacrylate, etc. Is mentioned. Specific examples of vinyl ether include vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether and the like. Specific examples of vinyl carboxylate include vinyl acetate, vinyl propionate, vinyl butyrate and the like. Specific examples of the amide monomer include acrylamide, methacrylamide, diacetone acrylamide, N-methylol acrylamide, N-methylol methacrylamide and the like. Specific examples of the acid chloride monomer include acrylic acid chloride and methacrylic acid chloride. Specific examples of the monomer having a nitrogen atom or a heterocyclic ring thereof include vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, and ethyleneimine. Specific examples of the polyoxyethylene resin include polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, Examples include polyoxyethylene lauryl phenyl ether, polyoxyethylene phenyl stearate, and polyoxyethylene pelargonate phenyl. Specific examples of celluloses include methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose and the like.

Specific examples of the dispersant include acids such as calcium phosphate salts and those that are soluble in alkali. When calcium phosphate is used as the dispersant, the calcium phosphate salt can be removed by dissolving the calcium salt with hydrochloric acid or the like and washing it with water or decomposing with an enzyme.
A catalyst can be used for the elongation reaction and / or the crosslinking reaction in producing the adhesive substrate. Specific examples of the catalyst include dibutyltin laurate and dioctyltin laurate.

As a method for removing the organic solvent from the dispersion liquid such as an emulsified slurry, the temperature of the entire reaction system is gradually raised to evaporate the organic solvent in the oil droplets, and the dispersion liquid is sprayed in a dry atmosphere to obtain the oil. Examples include a method of removing the organic solvent in the droplets. When the organic solvent is removed, toner base particles are formed. The toner base particles can be washed, dried, etc., and further classified. Classification may be performed by removing fine particle portions in a liquid by a cyclone, decanter, centrifugation, or the like, or classification may be performed after drying.
The obtained toner base particles may be mixed with particles such as a release agent and a charge control agent. At this time, by applying a mechanical impact force, it is possible to prevent particles such as a release agent from detaching from the surface of the toner base particles. As a method of applying mechanical impact force, a method of applying impact force to a mixture using a blade rotating at a high speed, throwing the mixture into a high-speed air current, and accelerating the particles or particles to an appropriate collision plate The method of making it collide etc. is mentioned. As an apparatus used in this method, an Ong mill (manufactured by Hosokawa Micron Corporation), an I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) and a pulverization air pressure are lowered, and a hybridization system (manufactured by Nara Machinery Co., Ltd.) Kryptron system (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.

  Since the toner of the present invention has a smooth surface, it has excellent properties such as transferability and chargeability, and can form a high-quality image. Further, when the toner of the present invention contains an adhesive substrate obtained by reacting a compound having an active hydrogen group with a polymer having reactivity to the active hydrogen group in an aqueous medium, the transferability and fixability are improved. Further excellent properties such as Therefore, the toner of the present invention can be used in various fields and can be suitably used for image formation by electrophotography.

  The volume average particle diameter of the toner of the present invention is preferably 3 to 8 μm, and more preferably 4 to 7 μm. When the volume average particle diameter is less than 3 μm, in the two-component developer, the toner may be fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier may be reduced. In the case of a one-component developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner may occur. When the volume average particle diameter exceeds 8 μm, it becomes difficult to obtain a high-resolution and high-quality image, and when the toner in the developer is balanced, the fluctuation of the toner particle diameter may increase. .

  The ratio of the volume average particle diameter to the number average particle diameter of the toner of the present invention is preferably 1.00 to 1.25, and more preferably 1.05 to 1.25. As a result, in the two-component developer, even if the toner balance for a long period of time is performed, the toner particle diameter in the developer is little changed, and good and stable developability can be obtained even in the case of long-term stirring in the developing device. . In the case of a one-component developer, even if the balance of the toner is performed, the fluctuation of the toner particle diameter is reduced, and the toner filming on the developing roller and the toner on a member such as a blade for thinning the toner Therefore, even when the developing device is used (stirred) for a long time, good and stable developability can be obtained, so that a high-quality image can be obtained. When this ratio exceeds 1.25, it becomes difficult to obtain a high-resolution and high-quality image, and when the balance of the toner in the developer is performed, the fluctuation of the toner particle diameter may increase. is there.

  The ratio of the volume average particle diameter to the volume average particle diameter and the number average particle diameter can be measured as follows using a particle size measuring device Multisizer III (manufactured by Beckman Coulter, Inc.). First, 0.1 to 5 ml of a surfactant such as an alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of an electrolyte aqueous solution such as an approximately 1% by mass sodium chloride aqueous solution. Next, about 2 to 20 mg of a measurement sample is added. The aqueous electrolyte solution in which the sample is suspended is subjected to a dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser, and then the volume and number of toners are measured using a 100 μm aperture to obtain the volume distribution and number distribution. calculate. From the obtained distribution, the volume average particle diameter and the number average particle diameter of the toner can be obtained.

The developer of the present invention contains the toner of the present invention, and may further contain other components appropriately selected such as a carrier. For this reason, it is excellent in transferability, chargeability, etc., and a high quality image can be formed stably. The developer may be a one-component developer or a two-component developer. However, when used in a high-speed printer or the like corresponding to the recent improvement in information processing speed, the developer has a long life. A two-component developer is preferred because it improves.
When the developer of the present invention is used as a one-component developer, even if the balance of the toner is performed, the fluctuation of the toner particle diameter is small, the filming of the toner on the developing roller, the blade for thinning the toner, etc. Therefore, good and stable developability and images can be obtained even with long-term stirring in the developing device.
When the developer of the present invention is used as a two-component developer, there is little fluctuation in the particle diameter of the toner even if the toner balance is maintained over a long period of time, and good and stable developability even with long-term agitation in the developing device. An image is obtained.

The carrier can be appropriately selected depending on the purpose, but a carrier having a core material and a resin layer covering the core material is preferable. The material of the core material can be appropriately selected from known materials, and examples thereof include 50 to 90 emu / g manganese-strontium-based material, manganese-magnesium-based material, and the like. The volume average particle diameter of the core material is preferably 10 to 150 μm, and more preferably 40 to 100 μm. If the volume average particle size is less than 10 μm, fine particles are increased in the carrier, and magnetization per particle may be reduced to cause carrier scattering. If it exceeds 150 μm, the specific surface area is decreased, and In the case of a full color with many solid portions, the reproduction of the solid portions may be deteriorated.
The content of the carrier in the two-component developer is preferably 90 to 98% by mass, and more preferably 93 to 97% by mass.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples. In the examples, “part” and “%” in each example are based on mass.

<Resin synthesis>
Bisphenol A, divalent carboxylic acid and 2 parts of dibutyltin oxide were charged into a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and reacted at 230 ° C. for 8 hours under normal pressure. Next, after reacting under reduced pressure of 10 to 15 mmHg for 5 hours, trimellitic anhydride was added to the reaction vessel and reacted under normal pressure to synthesize resin 1 (polyester resin) shown in Table 1. Acid value (KOH mg / g) = 15.3.

<Method for measuring acid value>
In accordance with the measurement method described in JIS K0070-1992, measurement is performed under the following conditions.
Sample preparation: 0.5 g of sample is added to 120 ml of toluene and dissolved by stirring at room temperature (23 ° C.) for about 10 hours. Further, 30 ml of ethanol is added to prepare a sample solution.
The measurement can be calculated by the apparatus described above, and specifically, the calculation is performed as follows.
Titrate with a pre-standardized N / 10 caustic potash to alcohol solution, and obtain the acid value from the consumption of the alcohol potash solution by the following calculation.
Acid value = KOH (ml) x N x 56.1 / sample mass (where N is a factor of N / 10 KOH)

<Measurement of resin melting point>
The melting point in the present invention is determined by the peak top showing the maximum endotherm of the DSC curve in differential scanning calorimetry (DSC). 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 50 ml / 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

<Master batch production>
50% of resin 1 shown in Table 1 and magenta pigment (CI Pigment Red 269 / manufactured by Dainichi Seika Co., Ltd., CI Pigment Violet 23 / DIC) mixed at the ratio shown in Table 1 and the surface treatment shown in Table 2 10% of Agent 1 was mixed at 1000 rpm for 5 minutes with a Henschel mixer (Mitsui Mine Co., Ltd.), then kneaded with an open roll kneader (Mitsui Mine Co., Ltd.), and 2 mm large with a Rotoplex crusher. A pigment dispersion powder was prepared as a master batch.

<Manufacture of toner>
In a beaker, 10 parts of polyester prepolymer, 75 parts of polyester resin, and 130 parts of ethyl acetate were stirred and dissolved. Next, 5 parts of paraffin wax and 20 parts of the above master batch were added, and the particle size was measured at a feeding speed of 1 kg / hour and a peripheral speed of the disk of 6 m / second using an ultra visco mill (manufactured by Imex). Three passes were performed under the condition of filling 80% by volume of 0.5 mm zirconia beads. Further, 2.7 parts of a ketimine compound was added and dissolved to prepare a toner material liquid.
Add 150 parts of an aqueous medium into a container, add 100 parts of toner material solution while stirring at 12,000 rpm using a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.), and mix for 10 minutes to prepare an emulsified slurry. did.
In a Kolben equipped with a stirrer and a thermometer, 100 parts of an emulsified slurry was charged, and the solvent was removed at 30 ° C. for 12 hours while stirring at a stirring peripheral speed of 20 m / min to obtain a dispersed slurry.
After filtering 100 parts of the dispersion slurry under reduced pressure, 100 parts of ion-exchanged water was added to the filter cake, followed by mixing at 12000 rpm for 10 minutes using a TK homomixer, followed by filtration. To the obtained filter cake, 300 parts of ion-exchanged water was added, mixed for 10 minutes at 12000 rpm using a TK homomixer, and then filtered twice. 20 parts of a 10 wt% aqueous sodium hydroxide solution was added to the obtained filter cake, mixed at 12000 rpm for 30 minutes using a TK homomixer, and then filtered under reduced pressure. To the obtained filter cake, 300 parts of ion-exchanged water was added, mixed at 12000 rpm for 10 minutes using a TK homomixer, and then filtered. To the obtained filter cake, 300 parts of ion-exchanged water was added, mixed for 10 minutes at 12000 rpm using a TK homomixer, and then filtered twice. Further, 20 parts of 10 wt% hydrochloric acid was added to the obtained filter cake, and the mixture was mixed for 10 minutes at 12000 rpm using a TK homomixer, and then filtered. To the obtained filter cake, 300 parts of ion-exchanged water was added, mixed for 10 minutes at 12000 rpm using a TK homomixer, and then filtered twice to obtain a filter cake.
The obtained final filter cake was dried at 45 ° C. for 48 hours using a circulating dryer, and sieved with a mesh having a mesh size of 75 μm to obtain toner mother particles. To 100 parts of the obtained toner base particles, 1.0 part of hydrophobic silica as an external additive and 0.5 part of hydrophobized titanium oxide are added and mixed using a Henschel mixer (Mitsui Mining Co., Ltd.). Thus, a toner for evaluation was produced.

  A toner for evaluation was produced in the same manner as in Example 1 except that 95 parts of the naphthol pigment and 5 parts of the dioxazine pigment in Example 1 were changed.

  An evaluation toner was prepared in the same manner as in Example 2 except that both of the magenta pigments in Example 2 were changed to powders and used without producing a master batch.

  An evaluation toner was produced in the same manner as in Example 2 except that the surface treating agent in Example 2 was not used.

  Evaluation toner in the same manner as in Example 2, except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 2 having a melting point of 81 ° C., an acid value of 1.2 (KOH mg / g) and a viscosity of 15 cp. Was made.

  A toner for evaluation was produced in the same manner as in Example 2, except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 2 having a melting point of 93 ° C. and an acid value of 23 (KOH mg / g) and a viscosity of 23 cp. did.

  A toner for evaluation was produced in the same manner as in Example 2 except that the masterbatch resin 1 in Example 2 was changed to resin 2 having a melting point of 118 ° C. and an acid value of 4.7 (KOH mg / g).

  A toner for evaluation was produced in the same manner as in Example 2 except that the masterbatch resin 1 in Example 2 was changed to Resin 3 having a melting point of 123 ° C. and an acid value of 46 (KOH mg / g).

  Toner for evaluation in the same manner as in Example 2 except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 4 having a melting point of 105 ° C. and an acid value of 18.9 (KOH mg / g) and a viscosity of 23 cp. Was made.

  Evaluation was conducted in the same manner as in Example 2 except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 5 having a melting point of 63 ° C. and an acid value of 9.6 (KOH mg / g) and a viscosity of 6.3 cp. A toner was prepared.

  Toner for evaluation in the same manner as in Example 2, except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 6 having a melting point of 120 ° C. and an acid value of 22.3 (KOH mg / g) and a viscosity of 31 cp. Was made.

  Evaluation was conducted in the same manner as in Example 2 except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 7 having a melting point of 71 ° C. and an acid value of 10.5 (KOH mg / g) and a viscosity of 3.5 cp. A toner was prepared.

  Toner for evaluation in the same manner as in Example 2, except that the surface treatment agent 1 in Example 2 was changed to the surface treatment agent 8 having a melting point of 108 ° C. and an acid value of 21.5 (KOH mg / g) and a viscosity of 55 cp. Was made.

[Comparative Example 1]
The masterbatch resin 1 in Example 2 was changed to a resin 4 having a melting point of 120 ° C. and an acid value of 15.3 (KOH mg / g), and the amount of naphthol pigment used in the magenta pigment (1) was 75 parts. A comparative evaluation toner was prepared in the same manner as in Example 2 except that the amount of the dioxazine pigment used as the magenta pigment (2) was changed to 25 parts.

[Comparative Example 2]
In the same manner as in Comparative Example 1, except that the amount of naphthol pigment used as the magenta pigment (1) in Comparative Example 1 was changed to 99.5 parts and the amount used of the dioxazine pigment used as the magenta pigment (2) was changed to 0.5. A toner for comparative evaluation was prepared.

[Comparative Example 3]
Comparative Example 1 and Comparative Example 1 except that the amount of naphthol pigment used as magenta pigment (1) in Comparative Example 1 was changed to 85 parts, and that the amount used was changed to 15 using quinacridone instead of dioxazine pigment as magenta pigment (2). Similarly, a comparative evaluation toner was produced.

[Comparative Example 4]
Comparative evaluation toner in the same manner as in Comparative Example 3, except that the amount of naphthol pigment used in the magenta pigment (1) in Comparative Example 3 was changed to 95 parts and the amount of quinacridone used in the magenta pigment (2) was changed to 5. Was made.

<Color reproducibility evaluation and coloring degree evaluation>
As with the image density evaluation, only the paper is imaged on Tokishi Art N 110Kg (Mitsubishi Paper Co., Ltd.) so that the attached amount is 0.4 mg / cm ^2, and the fixing member temperature is always 160 ° C. After being controlled, the sample was fixed at a linear velocity of 280 mm / sec to obtain a sample for evaluation.
The chromaticness index a * and b * in the L * a * b * color system (CIE: 1976) was measured for the formed solid image using a chromaticity meter (X-Rite 938, manufactured by X-Rite). The value of C * represented by the following formula (1) was obtained, and the saturation of each color toner was evaluated.
C * = [(a *) 2+ (b *) 2] 1/2 (1)
The evaluation criteria for saturation are as follows.
A: Very good. C * is 75 or more.
○: Good. C * is 73 or more and less than 75.
Δ: Slightly poor C * is 70 or more and less than 73.
X: Defect. C * is less than 70.
The results are shown in Table 3.
Further, from the calculated a * b *, the color difference from JapanColor was calculated by the following formula (2), and ΔE was evaluated.
ΔE = [(a *) 2- (b *) 2] 1/2 (2)
The evaluation criteria for color difference are as follows.
A: Very good. ΔE is less than 1.
○: Good. ΔE is 1 or more and less than 3
Δ: Slightly defective ΔE is 3 or more and less than 5 ×: Defect. ΔE is 5 or more The results are shown in Table 3.
Further, the image density of the sample was measured using a chromaticity meter (X-Rite 938, manufactured by X-Rite).
The image density evaluation criteria are as follows.
A: Very good. Image density 1.5 or higher
○: Good. C * is 1.4 or more and less than 1.5.
Δ: Slightly poor C * is 1.3 or more and less than 1.4.
X: Defect. C * is less than 1.3.
The results are shown in Table 3.

<Long-term running test under high temperature and high humidity>
The toner obtained above and 60 μm ferrite carrier were stirred and mixed at a toner concentration of 4% for 20 minutes to obtain a two-component developer. The two-component developer was subjected to a printing durability test of 50000 sheets at a document density of 5% using a copying machine (Imagio Neo C355) manufactured by Ricoh Co., Ltd. in an environment of 40 ° C./80%. The image densities of the formed first and 50,000th fixed images were measured by a reflection densitometer manufactured by Macbeth (modified so that three decimal places can be measured). Measure the density difference between the unused paper and the white area of the fixed image. If the density difference is less than 0.01, ◎, 0.01 to less than 0.02, ○, 0.02 to less than 0.03 Was judged as x for cases where Δ was 0.03 or more.
Table 3 shows the results of the evaluation.

According to the evaluation results, the toner of Comparative Example 1 was a toner having a low color saturation and a large color difference because the ratio of the dioxazine pigment was high. Since the toner of Comparative Example 2 has a low ratio of the dioxazine pigment, the toner has a low bluish color and a large color difference. Since the quinacridone pigment was used as the magenta pigment in the toners of Comparative Example 3 and Comparative Example 4, the pigment segregated and became a toner with low chroma and large color difference.
On the other hand, since the toners of Examples 1 to 13 satisfy the requirements of the scope of the present invention, toners having high saturation, excellent hue, and no scumming during running under high temperature and high humidity were obtained.

Japanese Patent No. 2537503 JP-A-50-120632 JP 63-25664 A Japanese Patent Laid-Open No. 5-127422 JP-A-8-179556 Japanese Patent No. 3661422 JP 2003-215847 A

Claims (23)

  In a toner including toner base particles granulated from a suspension obtained by suspending an oil phase in an organic solvent containing a toner material including at least a binder resin component, a colorant, and a release agent in an organic solvent. A magenta toner for electrophotography, wherein a naphthol pigment and a dioxazine pigment are used as an agent, and a mixing ratio of the naphthol pigment and the dioxazine pigment is 99: 1 to 80:20.   2. The magenta toner for electrophotography according to claim 1, wherein a master batch in which the colorant is previously dispersed in a resin for the master batch is used.   The magenta toner for electrophotography according to claim 1, wherein the colorant is surface-treated with an acidic surface treatment agent.   The electrophotographic magenta toner according to claim 3, wherein the surface treatment agent has an acid value of 3 KOHmg / g or more and 20 KOHmg / g or less.   The magenta toner for electrophotography according to any one of claims 2 to 4, wherein the resin for the master batch has an acid value of 5 KOHmg / g or more and 40 KOHmg / g or less.   The surface treatment agent and the colorant are previously dispersed in the masterbatch resin, and the dispersion of the resin, the surface treatment agent and the colorant is melt kneading. The magenta toner for electrophotography according to any one of 5.   The magenta toner for electrophotography according to claim 6, wherein the melting point of the surface treatment agent is lower than the melting point of the resin.   The magenta toner for electrophotography according to claim 6 or 7, wherein the melting point of the surface treatment agent is 70 ° C or higher and 110 ° C or lower.   9. The electrophotographic magenta toner according to claim 1, wherein the release agent has a viscosity at 90 ° C. of 5 centipoise or more and 50 centipoise or less.   The surface treatment agent and the colorant are previously dispersed in the masterbatch resin, and the dispersion of the masterbatch resin, the release agent, and the colorant is used as a colorant for the presscake pigment after pigment washing. 10. The electrophotographic magenta toner according to claim 6, wherein the toner is an electrophotographic magenta toner.   The dispersion of the masterbatch resin, the surface treatment agent, and the colorant includes melt mixing of the masterbatch resin, the surface treatment agent, and the colorant, and the melt mixing uses an open-type melt kneader. The magenta toner for electrophotography according to claim 10.   Production of toner in which an oil phase of an organic solvent containing a toner material containing at least a binder resin component, a colorant, and a release agent is suspended in an aqueous medium in the form of droplets, and toner base particles are granulated from the droplets In the method, a naphthol pigment and a dioxazine pigment are used as colorants, and the mixing ratio of the naphthol pigment and the dioxazine pigment is 99: 1 to 80:20. Method.   13. The method for producing a magenta toner for electrophotography according to claim 12, wherein a master batch in which the colorant is dispersed in advance in a resin for the master batch is used.   The method for producing a magenta toner for electrophotography according to claim 12 or 13, wherein the colorant is surface-treated with an acidic surface treatment agent.   The method for producing a magenta toner for electrophotography according to any one of claims 12 to 14, wherein the surface treatment agent has an acid value of 3 KOHmg / g or more and 20 KOHmg / g or less.   16. The method for producing a magenta toner for electrophotography according to claim 13, wherein the master batch resin has an acid value of 5 KOHmg / g or more and 40 KOHmg / g or less.   15. The method according to claim 14, further comprising a step of dispersing the binder resin, the surface treatment agent, and the colorant in advance, wherein the step of dispersing the binder resin, the surface treatment agent, and the colorant is melt kneading. The method for producing a magenta toner for electrophotography according to any one of 16.   18. The method for producing an electrophotographic magenta toner according to claim 17, wherein the melting point of the surface treatment agent is lower than the melting point of the masterbatch resin.   The method for producing a magenta toner for electrophotography according to claim 17 or 18, wherein the melting point of the surface treatment agent is 70 ° C or higher and 110 ° C or lower.   The method for producing an electrophotographic magenta toner according to any one of claims 17 to 19, wherein the release agent has a viscosity at 90 ° C of 5 centipoise or more and 50 centipoise or less.   21. The step of dispersing the masterbatch resin, the surface treatment agent, and the colorant in advance uses a presscake pigment after pigment washing as the colorant. Manufacturing method of magenta toner for electrophotography.   The magenta toner for electrophotography according to any one of claims 17 to 21, wherein an open-type melt kneader is used in the step of melting and mixing the resin for the master batch, the surface treatment agent, and the colorant. Production method.   23. The magenta for electrophotography according to claim 12, further comprising a step of dispersing the binder resin component, a release agent, and a colorant in the organic solvent to form the oil phase. Toner manufacturing method.