JP4462027B2 - Method for producing resin particle dispersion and method for producing electrostatic charge developing toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin particle dispersion liquid for an electrostatic image developing toner in which resin particles are stably emulsified and dispersed in an aqueous medium with low energy, and to provide a method for manufacturing an electrostatic image developing toner, by which an electrostatic image developing toner amply satisfying toner properties can be manufactured by using the dispersion, and to provide an electrostatic image developing toner obtained by the method. <P>SOLUTION: Polycondensed particles in a resin particle dispersion for an electrostatic image developing toner are dispersed in a median diameter of 0.05-2.0 &mu;m, after polycondensing a polycondensable monomer in an aqueous medium. The electrostatic image developing toner is obtained, e.g., by an emulsion polymerization-coalescence method by using the resulting resin particle dispersion. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

The present invention relates to a method for producing electrostatic charge developing toner over to be used for developing the electrostatic latent image formed by an electrophotographic method or an electrostatic recording method or the like by the developer, as well as the resin particle dispersion to be used as a raw material The present invention relates to a method for producing a liquid.

  A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In the electrophotographic method, an electrostatic image is formed on the photoreceptor by charging and exposure processes, the electrostatic latent image is developed with a developer containing toner, and visualized through transfer and fixing process steps. The developer used here includes a two-component developer composed of a toner and a carrier and a one-component developer using a magnetic toner or a non-magnetic toner alone. The toner is usually produced by using a thermoplastic resin as a pigment. In addition, a kneading and pulverizing method is used in which melt-kneading is performed together with a release agent such as a charge control agent and wax, and the mixture is cooled, finely pulverized, and further classified. In these toners, if necessary, inorganic and organic particles for improving fluidity and cleaning properties may be added to the toner particle surfaces.

  In recent years, copiers, printers using color electrophotography, and multi-function machines such as those and facsimiles have been widely used. However, in order to achieve moderate gloss in color image reproduction and transparency to obtain an excellent OHP image, It is generally difficult to use a release agent such as wax. For this reason, since a large amount of oil is applied to the fixing roll to assist the peeling, it is difficult to add a sticky feeling to a copy image containing OHP or to add an image to the image with a pen or the like, and to produce a non-uniform glossy feeling. There are many things. In normal black-and-white copying, commonly used waxes such as polyethylene, polypropylene, and paraffin are more difficult to use because they impair OHP transparency.

  For example, even if the transparency is sacrificed, it is difficult to suppress the toner exposure to the surface by the conventional toner production method by the kneading and pulverization method. Problems such as deterioration of the image quality and filming on the developing machine and the photoreceptor.

  As a fundamental improvement method for these problems, an oil phase composed of a monomer and a colorant as a resin raw material is dispersed in an aqueous phase and directly polymerized into a toner. There has been proposed a production method by a polymerization method in which the exposure to the surface is controlled by inclusion.

  In addition, as means for enabling intentional control of the toner shape and surface structure, Japanese Patent Application Laid-Open No. 63-282275 and Japanese Patent Application Laid-Open No. 6-250439 propose a method for producing a toner by an emulsion polymerization aggregation method. In general, a resin particle dispersion is prepared by emulsion polymerization or the like, while a colorant dispersion in which a colorant is dispersed in a solvent is prepared and mixed to form an aggregate corresponding to the toner particle diameter and heated. Is a method for producing toner by fusing together.

  These manufacturing methods not only realize the inclusion of the wax, but also facilitate the reduction of the toner diameter, and enable higher resolution and clearer image reproduction.

  In order to provide high-quality images in the electrophotographic process as described above and to maintain stable toner performance under various mechanical stresses, pigment, mold release material selection, amount optimization, surface release In addition to suppressing the exposure of the mold, it is extremely important to improve the releasability in the absence of gloss and fixing oil and to suppress hot offset by optimizing the resin properties.

  On the other hand, in order to reduce energy consumption, a technology capable of fixing at a lower temperature is desired. Particularly in recent years, in order to save energy, it is desirable to stop energization of the fixing machine except during use. ing. Accordingly, the temperature of the fixing device needs to be energized and instantaneously raised to the operating temperature. For this purpose, it is desirable to make the heat capacity of the fixing machine as small as possible. In this case, however, the temperature fluctuation of the fixing machine tends to be larger than before. That is, the overshoot of the temperature after the start of energization increases, and on the other hand, the temperature drop due to paper passing also increases. In addition, when paper having a width smaller than the width of the fixing device is continuously passed, the temperature difference between the paper passing portion and the non-paper passing portion also increases. In particular, when used in high-speed copying machines and printers, the power supply capacity tends to be insufficient, and there is a strong tendency to cause the above phenomenon. Therefore, there is a strong demand for a toner for electrophotography having a wide fixing latitude, which is fixed at a low temperature and does not cause an offset to a higher temperature region.

  As a means for lowering the fixing temperature of the toner, it is known to use a polycondensation type crystalline resin showing a sharp melting behavior with respect to the temperature as the binder resin constituting the toner. In many cases, the melt kneading and pulverization method is difficult to pulverize and generally cannot be used.

  Furthermore, the polymerization of the polycondensation type resin requires a reaction that takes 10 hours or more under stirring at a high temperature exceeding 200 ° C. under high power and under a high vacuum, resulting in a large amount of energy consumption. For this reason, enormous capital investment is often required to obtain durability of the reaction equipment.

  In addition, when the toner is prepared by the emulsion polymerization aggregation method as described above, after the polycondensation type crystalline resin is polymerized, it is emulsified in an aqueous medium and aggregated with a pigment or wax in a latex state. Can be fused and united.

  However, when the polycondensation resin is emulsified, it is emulsified by high shear under high heat exceeding 150 ° C., or the solvent is removed after the solution which has been dissolved in the solvent and reduced in viscosity is dispersed in an aqueous medium. It requires a very inefficient and energy consuming process.

  In addition, it is difficult to avoid problems such as hydrolysis during emulsification in an aqueous medium, and indeterminate factors are inevitable in material design.

  These problems are conspicuous in the crystalline resin, but are not limited to this, and the same is true for the amorphous resin.

By the way, there is a report that polycondensation of polyester in an aqueous medium, which has been considered difficult in the past, is possible in an aqueous medium (Sam JC, Chou YJ. US Patent, 4 355 154; 1982). There is also a report of polycondensation of polyester in an aqueous medium in the presence of a catalyst having a sulfonic acid group (USP 4355154).
JP-A-63-282275 JP-A-6-250439 Macromolecules, 2003, 36, 1772-1774. Sam JC, Chou YJ. US Patent, 4 355 154; 1982 USP 4355154

  As described above, when toner preparation is carried out, a polycondensation type crystalline resin is polymerized and then emulsified in an aqueous medium. However, if resin particles can be formed in the aqueous medium as described above, the resin There is no need to emulsify the particles in an aqueous medium, which is considered very advantageous.

  However, in the above report, the resin particles are emulsified and dispersed in an aqueous medium in an unstable state. When a toner is prepared using this dispersion, the particle size and distribution of the toner are determined according to recent technical requirements. The current situation is that the toner quality deteriorates, resulting in a decrease in image quality and the like, and a toner that sufficiently satisfies the toner characteristics cannot be obtained. In addition, even when polymerized polycondensation type crystalline resin and then emulsified in an aqueous medium, the resin particles are still emulsified and dispersed in an aqueous medium in an unstable state according to recent technical requirements. Is desired.

Accordingly, an object of the present invention is to solve the conventional problems and achieve the following object. That is, the present invention is to provide a method for producing a resin particle dispersion in which resin particles are stably emulsified and dispersed in an aqueous medium with low energy. Further, by using this, it is to provide a manufacturing how the electrostatic developing toner which can produce an electrostatic charge developing toner which fully satisfies the toner properties.

The above problem is solved by the following means. That is,
The method for producing a resin particle dispersion according to the present invention uses a scandium catalyst having an alkylbenzene sulfonate structure as a polycondensation catalyst, and at least a polyvalent carboxylic acid and a polyol as a polycondensation monomer as a raw material for polyester particles. In the aqueous medium to form polyester particles dispersed with a median diameter of 0.05 μm or more and 2.0 μm or less .

On the other hand, in the method for producing an electrostatic charge developing toner of the present invention, at least a step of aggregating the resin particles to obtain agglomerated particles in a dispersion in which the resin particles are dispersed, and fusing the aggregated particles by heating. And having a process
At least one of the dispersions in which the resin particles are dispersed is obtained by the method for producing a resin particle dispersion of the present invention .

According to the present invention, a method for producing a resin particle dispersion in which resin particles are stably emulsified and dispersed in an aqueous medium with low energy can be provided. Further, by using this, the toner properties can provide sufficient Satisfied electrostatic developing toner which can produce an electrostatic charge developing toner production how.

  Hereinafter, the present invention will be described in detail.

(Resin particle dispersion)
In the resin particle dispersion of the present invention, polycondensation resin particles are emulsified and dispersed in an aqueous medium with a median diameter of 0.05 μm to 2.0 μm, and the polycondensation resin particles are polycondensable in an aqueous medium. It is obtained by direct polycondensation of monomers.
However, the resin particle dispersion of the present invention and the method for producing the same apply a scandium catalyst having an alkylbenzene sulfonate structure as a polycondensation catalyst, and at least a polyvalent monomer as a polycondensable monomer that is a raw material for polyester particles. Carboxylic acid and polyol are polycondensed in an aqueous medium to form polyester particles.

  In such a resin particle dispersion of the present invention, the polycondensable monomer is directly polycondensed in an aqueous medium so that the median diameter of the polycondensation resin particles is 0.05 μm or more and 2.0 μm or less. The polycondensation resin particles can be obtained with low energy. Moreover, the dispersion state of the polycondensation resin particles in the medium in the aqueous medium is realized, for example, in an isolated state in water, and becomes a stable state for a long time before the agglomeration operation using an aggregating agent for tonerization. Only when the operation is performed, it is possible to form aggregated particles with high controllability. Therefore, when this dispersion is used, the particle size distribution as a toner is improved and the composition and structure of each toner are made uniform, so that the toner characteristics are sufficient. A satisfactory toner is obtained.

  Here, the median diameter (center diameter) of the polycondensation resin particles is 0.05 μm or more and 2.0 μm or less, preferably 0.1 μm or more and 1.5 μm or less, more preferably 0.1 μm or more and 1.0 μm or less. is there. When the median diameter is in the above range, the dispersion state of the polycondensation resin particles in the medium in the aqueous medium is stabilized as described above. Therefore, if the median diameter is too small at the time of toner preparation, the agglomeration property at the time of particle formation is deteriorated, free resin particles are easily generated, and the viscosity of the system is also easily increased. It becomes difficult to control the diameter. On the other hand, if it is too large, the generation of coarse powder is likely to occur, the particle size distribution is deteriorated, and the release agent such as wax is easily released, so that the releasability at the time of fixing and the offset generation temperature are lowered.

  The median diameter of the polycondensation resin particles can be measured, for example, with a laser diffraction particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.).

  In addition, the polycondensation resin particles are suitable not only for the median diameter, but also for generation of ultrafine powder and ultracoarse powder, and the ratio of the polycondensation resin particles having a median diameter of 0.03 μm or less or 5.0 μm or more. Is preferably 10% or less of the total, more preferably 5% or less. This ratio can be obtained by plotting the relationship between the particle diameter and the frequency integration in the measurement result in LA 920 and obtaining from the frequency integration amount of 0.03 μm or less or 5.0 μm or more.

  Hereafter, the manufacturing method of the resin particle dispersion liquid of this invention is demonstrated. In order to obtain the resin particle dispersion of the present invention, for example, a polycondensable monomer is first emulsified and dispersed in an aqueous medium by, for example, mechanical shearing or ultrasonic waves as a target resin particle raw material. At this time, if necessary, additives such as a polycondensation catalyst and a surfactant are also added to the water-soluble medium. And polycondensation is advanced by, for example, heating the solution.

  Usually, polycondensation resins do not proceed in an aqueous medium in principle because they are dehydrated during polymerization. However, for example, when a polycondensable monomer is emulsified in an aqueous medium together with a surfactant that causes micelles to form in the aqueous medium, the monomer is placed in a micro hydrophobic field in the micelle. Then, dehydration occurs, and the generated water can be discharged into an aqueous medium outside the micelles to allow polymerization to proceed. In this way, a dispersion liquid in which polycondensation resin particles are emulsified and dispersed in an aqueous medium is obtained with low energy.

Here, in order to control the median diameter of the obtained polycondensation resin particles within the above range, or to control the ratio of the polycondensation resin particles having a large particle size and a small particle size to be low, for example, the following treatment is performed. Is preferred.
1) The polycondensable monomer is not directly added to the aqueous medium, but the polycondensable monomer is once mixed and melted together with other additives (for example, a polycondensation catalyst and a surfactant). A method in which this oil-based solution is added to an aqueous medium, subjected to first stirring (for example, stirring by a homogenizer), and further subjected to second stirring (for example, stirring by ultrasonic waves) to emulsify and disperse.
2) The polymerizable monomer is mixed and melted with other additives (for example, a polycondensation catalyst and a surfactant), and this oil-based solution is stirred and emulsified (for example, stirred by a homogenizer) in an aqueous medium heated to, for example, about 100 ° C. Emulsification), and further finely emulsified and dispersed (for example, finely emulsified and dispersed by Yoshida Kikai Kogyo Nanomizer),
3) A polymerizable monomer is mixed and melted with other additives (for example, a polycondensation catalyst and a surfactant), and a small amount of a solvent (for example, ethyl acetate) is added, followed by stirring and emulsification in an aqueous medium (for example, a homogenizer). Stirring and emulsification), and further finely emulsified and dispersed (for example, finely emulsified and dispersed by Nanomizer manufactured by Yoshida Kikai Kogyo Co., Ltd.).
4) A polymerizable monomer is mixed and melted together with other additives (for example, a polycondensation catalyst and a surfactant), and stirred and emulsified while gradually adding an aqueous medium heated to, for example, about 100 ° C. to the oil-based solution ( For example, a method of realizing phase inversion emulsification by stirring and emulsifying with a homogenizer and further adding an aqueous medium or a surfactant as necessary.

  In order to polycondense the polycondensable monomer at a low temperature, a polycondensation catalyst is usually used. As such a polycondensable catalyst having catalytic activity at a low temperature, an acid having a surface active effect, a rare earth-containing catalyst, or a hydrolase is preferably exemplified. By using these catalysts, for example, polycondensation can be caused in a room temperature aqueous medium at 100 ° C. or lower. In addition, in order to advance the polycondensation faster or to use a wider range of monomers, the polycondensation can be advanced in an aqueous medium under heating at 100 ° C. or higher.

  An acid having a surface-active effect is a catalyst having a chemical structure composed of a hydrophobic group and a hydrophilic group, and having an acid structure in which at least a part of the hydrophilic group is composed of protons, and has both an emulsifying function and a catalytic function. It is. Examples of acids having a surface active effect include alkylbenzene sulfonic acids such as dodecylbenzene sulfonic acid, isopropyl benzene sulfonic acid, keryl benzene sulfonic acid, and camphor sulfonic acid, alkyl sulfonic acid, alkyl disulfonic acid, and alkylphenol sulfonic acid. , Alkyl naphthalene sulfonic acid, alkyl tetralin sulfonic acid, alkyl allyl sulfonic acid, petroleum sulfonic acid, alkyl benzimidazole sulfonic acid, higher alcohol ether sulfonic acid, alkyl diphenyl sulfonic acid, monobutyl phenyl phenol sulfuric acid, dibutyl phenyl phenol sulfuric acid, dodecyl sulfuric acid Higher fatty acid sulfate, higher alcohol sulfate, higher alcohol ether sulfate, higher fatty acid amide alkylol sulfate , Higher fatty acid amide alkylated sulfate, naphthenyl alcohol sulfate, sulfated fat, sulfosuccinate, various fatty acids, sulfonated higher fatty acid, higher alkyl phosphate, resin acid, resin acid alcohol sulfate, naphthenic acid, and All these salt compounds are mentioned, and a plurality of them may be combined as necessary.

As the rare earth-containing catalyst, lanthanoid elements such as lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), and the like are effective, particularly alkylbenzene sulfonates and alkyl sulfates. Ester salts or those having a triflate structure are effective. The metal triflate is preferably a compound represented by the structural formula X (OSO ₂ CF ₃ ) ₃ X. In the formula, X is scandium (Sc), yttrium (Y), ytterbium (Yb), samarium (Sm), or the like.

  Further, as the rare earth-containing catalyst, lanthanoid triflate and the like are also preferable. The lanthanoid triflate is detailed in the Journal of Synthetic Organic Chemistry, Vol. 53, No. 5, p44-54).

  The hydrolase is not particularly limited as long as it catalyzes an ester synthesis reaction. Examples of the hydrolase include EC (enzyme number) 3.1 group (Maruo, Lipoprotein lipase, etc.) such as carboxyesterase, lipase, phospholipase, acetylesterase, pectinesterase, cholesterol esterase, tannase, monoacylglycerol lipase, lactonase and lipoprotein lipase. Hydrolysis enzymes classified into EC 3.2 group that act on glycosyl compounds such as esterase, glucosidase, galactosidase, glucuronidase, and xylosidase classified as “Enzyme Handbook” supervised by Tamiya (1982) etc., epoxide hydrase, etc. Classified into EC3.4 group that acts on peptide bonds such as hydrolase, aminopeptidase, chymotrypsin, trypsin, plasmin, subtilisin etc. And hydrolase classified into EC 3.7 group such as hydrolase and phloretin hydrase.

  Among these esterases, the enzyme that hydrolyzes glycerol esters and liberates fatty acids is called lipase, but lipase has high stability in organic solvents, catalyzes ester synthesis reaction in high yield, and can be obtained at a low price. There are advantages such as. Therefore, it is desirable to use lipase also in the manufacturing method of the polyester of this invention from the surface of a yield or cost.

  Lipases of various origins can be used, but preferred are the genus Pseudomonas, the genus Alcaligenes, the genus Achromobacter, the genus Candida, the genus Aspergillus, Examples thereof include lipases obtained from microorganisms such as (Rhizopus) genus and Mucor genus, lipases obtained from plant seeds, lipases obtained from animal tissues, pancreatin, and steapsin. Among these, it is desirable to use lipases derived from microorganisms of the genus Pseudomonas, Candida, and Aspergillus.

  These polycondensation catalysts may be used alone or in combination.

  On the other hand, examples of the polycondensation monomer used for polycondensation include polycarboxylic acids, polyols, and polyamines. In particular, the polycondensation monomer is preferably a polyester obtained by using a polycarboxylic acid and a polyol.

  The polyvalent carboxylic acid is a compound containing two or more carboxyl groups in one molecule. Among these, a divalent carboxylic acid is a compound containing two carboxyl groups in one molecule. For example, oxalic acid, succinic acid, maleic acid, adipic acid, β-methyladipic acid, azelaic acid, sebacic acid, Nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, fumaric acid, citraconic acid, diglycolic acid, cyclohexane-3,5-diene-1,2-carboxylic acid, malic acid, citric acid, hexahydroterephrine Tar acid, malonic acid, pimelic acid, tartaric acid, mucoic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylenedi Glycolic acid, p-phenylene diglycolic acid, o-phenylene jig Cholic acid, diphenylacetic acid, diphenyl-p, p'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracene dicarboxylic acid, etc. Can do. Examples of the polyvalent carboxylic acid other than the divalent carboxylic acid include trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, and pyrenetetracarboxylic acid.

  In particular, among polycarboxylic acids, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decane dicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, terephthalic acid Trimellitic acid, pyromellitic acid and the like are preferably used. Since these polyvalent carboxylic acids are hardly soluble or insoluble in water, the ester synthesis reaction proceeds in a suspension in which the polyvalent carboxylic acid is dispersed in water.

  A polyol is a compound containing two or more hydroxyl groups in one molecule. Among these, divalent polyol is a compound containing two hydroxyl groups in one molecule, such as ethylene glycol, propylene glycol, butanediol, diethylene glycol, hexanediol, cyclohexanediol, octanediol, decanediol, dodecanediol, etc. Can be mentioned. Examples of polyols other than divalent polyols include glycerin, pentaerythritol, hexamethylol melamine, hexaethylol melamine, tetramethylol benzoguanamine, and tetraethylol benzoguanamine.

  In particular, among polyols, it is preferable to use divalent polyols such as 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol. Since these polyols are hardly soluble or insoluble in water, the ester synthesis reaction proceeds in a suspension in which the polyol is dispersed in water.

  Further, an amorphous resin or a crystalline resin can be easily obtained by a combination of these polycondensable monomers.

  For example, polyvalent carboxylic acids used to obtain crystalline polyesters and crystalline polyamides include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, peric acid, azelaic acid, sebacic acid, Maleic acid, fumaric acid, citraconic acid, itaconic acid, glutamic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, these And acid anhydrides or acid chlorides thereof.

  Further, for example, as the polyol used for obtaining the crystalline polyester, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1, 4, butenediol, neopentyl glycol, 1,5-pentane glycol, 1,6-hexane glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetra Mention may also be made of methylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A and the like.

  Also, for example, polyamines used to obtain polyamides include ethylenediamine, diethylenediamine, triethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butanediamine, 1,4, butene. Examples include diamine, 2,2-dimethyl-1,3-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,4-cyclohexanediamine, and 1,4-cyclohexanedimethylamine. .

  The polycondensation resin particles obtained by polycondensation of such a polycondensable monomer are preferably crystalline. In particular, by using a crystalline resin, low-temperature fixing of toner can be easily realized.

  As such a crystalline polycondensation resin, polyester obtained by reacting 1,9 nonanediol and 1,10 decamethylenecarboxylic acid, or cyclohexanediol and adipic acid, 1,6 hexanediol and sebacic acid, Polyester obtained by reacting, polyester obtained by reacting ethylene glycol and succinic acid, polyester obtained by reacting ethylene glycol and sebacic acid, reacting 1,4-butanediol and succinic acid Mention may be made of the polyester obtained. Among these, polyesters obtained by reacting 1,9 nonanediol with 1,10 decamethylene carboxylic acid and 1,6 hexanediol with sebacic acid are more preferable.

  Here, the crystalline melting point Tm in the case of crystallinity is 50 to 120 ° C, preferably 55 to 90 ° C. When Tm is less than 50 ° C., the cohesive force of the binder resin itself in a high temperature range is reduced, and therefore, peeling is likely to deteriorate and hot offset is likely to occur during fixing. This is because the minimum fixing temperature may rise without being obtained.

Here, for the measurement of the melting point of the crystalline resin, a differential scanning calorimeter (DSC) was used, and the input shown in JIS K-7121 when measuring from room temperature to 150 ° C. at a heating rate of 10 ° C. per minute. It can be determined as the melting peak temperature of the compensated differential scanning calorimetry. The crystalline resin may show a plurality of melting peaks, but in the present invention, the maximum peak is regarded as the melting point.
Moreover, the glass transition point of an amorphous resin means the value measured by the method (DSC method) prescribed | regulated to ASTMD3418-82.

  On the other hand, when the polycondensable resin particles are amorphous, the glass transition point Tg is 50 to 80 ° C., preferably 50 to 65 ° C. When Tg is less than 50 ° C., the cohesive strength of the binder resin itself in a high temperature range is reduced, so that hot offset is likely to occur during fixing, and when it exceeds 80 ° C., sufficient melting cannot be obtained. This is because the fixing temperature may increase.

  The weight average molecular weight of the polycondensation resin particles obtained by polycondensation of the polycondensable monomer is suitably in the range of 1500 to 60000, preferably 3000 to 40000. When the weight average molecular weight is less than 1500, the cohesive force of the binder resin tends to decrease and the hot offset property may decrease. When the weight average molecular weight exceeds 60000, the hot fixing property is good but the minimum fixing temperature may increase. . Further, it may be partially branched or cross-linked by selecting the carboxylic acid valence or alcohol valence of the monomer.

  The particle size of the polycondensation resin particles obtained by polycondensation of the polycondensable monomer is preferably 10 μm or less in terms of the volume center particle size, more preferably 7 μm or less, 1 μm or less. When the particle diameter is larger than 10 μm, it is not preferable in terms of image quality characteristics such as resolution when used as a toner. Further, when the particle diameter is larger than 10 μm, the molecular weight increase and the speed in polycondensation are not sufficient, which is a problem in terms of image quality strength after fixing in production.

  Thus, in order to obtain polycondensation resin particles having a predetermined particle size in an aqueous medium, the polymerization method is suspension polymerization method, dissolution suspension method, miniemulsion method, microemulsion method, microemulsion method, multistage swelling. It is preferable to use a heterogeneous polymerization form in an ordinary aqueous medium such as a method or an emulsion polymerization method including seed polymerization. In this case, as shown above, the polycondensation reaction, and finally the final molecular weight and the polymerization rate depend on the final particle size of the particles, so that the most preferable particle size form of 1 μm is achieved, and the efficiency is high. As a production form capable of achieving the production, a polymerization method in which submicron particles of 1 μm or less, such as a miniemulsion method and a microemulsion method, are used as the final form is more preferable.

  When polycondensation resin particles are polycondensed in an aqueous medium, the above materials are emulsified or dispersed in the aqueous medium using, for example, mechanical shear or ultrasonic waves. Accordingly, a surfactant, a polymer dispersant, an inorganic dispersant, and the like can be added to the aqueous medium.

  Examples of the surfactant used herein include anionic surfactants such as sulfate ester, sulfonate, and phosphate ester; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene glycol And nonionic surfactants such as polyphenols, alkylphenol ethylene oxide adducts, and polyhydric alcohols. Among these, anionic surfactants and cationic surfactants are preferable. The nonionic surfactant is preferably used in combination with the anionic surfactant or the cationic surfactant. The said surfactant may be used individually by 1 type, and may use 2 or more types together. As anionic surfactants, sodium dodecylbenzenesulfonate, sodium alkylnaphthalenesulfonate, sodium arylalkylpolyethersulfonate, 3,3-disulfonediphenylurea-4,4-diazo-bis-amino-8-naphthol-6 Sodium sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sodium sulfonate, dialkylsulfosuccinate Sodium sulfate, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium caprate, sodium caprylate, caproic acid Thorium, potassium stearate, and the like calcium oleate. Examples of the cationic surfactant include alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, distearyl ammonium chloride and the like. Nonionic surfactants include polyethylene oxide, polypropylene oxide, combinations of polypropylene oxide and polyethylene oxide, esters of polyethylene glycol and higher fatty acids, alkylphenol polyethylene oxide, esters of higher fatty acids and polyethylene glycol, higher fatty acids and polypropylene oxide. Examples thereof include esters and sorbitan esters. Examples of the polymer dispersant include sodium polycarboxylate and polyvinyl alcohol, and examples of the inorganic dispersant include calcium carbonate. However, these do not limit the present invention. Further, in order to prevent the Ostwald Ripping phenomenon of the monomer emulsion particles in an ordinary aqueous medium, a higher alcohol represented by heptanol or octanol or a higher aliphatic hydrocarbon represented by hexadecane is often added as a stabilizer. It is also possible.

  In addition, when polycondensation resin particles are polycondensed in an aqueous medium, components necessary for normal toner such as a fixing agent such as a colorant and wax, and other charging assistants are mixed in advance in the aqueous medium, and then polycondensed. At the same time, it can be mixed in the polycondensation resin particles.

(Method for producing electrostatic charge developing toner)
In the method for producing an electrostatic charge developing toner of the present invention, at least a step of aggregating the resin particles to obtain aggregated particles (aggregation step) in a dispersion in which the resin particles are dispersed, and heating the aggregated particles And a step of fusing (fusing step). And in this manufacturing method called emulsion polymerization aggregation method, the resin particle dispersion of the present invention is applied as a dispersion in which resin particles are dispersed.

  In the aggregation step, the polycondensation resin particles in the resin particle dispersion of the present invention are prepared in an aqueous medium, so that they can be used as they are as a resin dispersion, and this resin particle dispersion can be used as needed. Aggregated particles having a toner diameter can be formed by mixing with the colorant particle dispersion and the release agent particle dispersion, adding an aggregating agent, and heteroaggregating these particles. In addition, after forming the first aggregated particles by aggregation in this way, the resin particle dispersion of the present invention or another resin particle dispersion is further added to form the second shell layer on the surface of the first particles. Is also possible. In this illustration, the colorant dispersion is separately adjusted. However, when the colorant is mixed in advance with the polycondensation resin particles, the colorant dispersion is not necessary.

  Here, as a flocculant, besides a surfactant, an inorganic salt or a divalent or higher metal salt can be suitably used. In particular, when a metal salt is used, it is preferable in characteristics such as cohesion control and toner chargeability. Further, for example, a surfactant can be used for emulsion polymerization of resin, dispersion of pigment, dispersion of resin particles, dispersion of release agent, aggregation, stabilization of aggregated particles, and the like. Specifically, sulfate surfactants, sulfonates, phosphates, soaps and other anionic surfactants, amine salts, quaternary ammonium salts and other cationic surfactants, polyethylene glycols, It is also effective to use nonionic surfactants such as alkylphenol ethylene oxide adducts and polyhydric alcohols as the dispersing means, and as a dispersion means, general use such as a ball mill, sand mill, dyno mill having a rotating shear homogenizer or media Can be used

  In addition to the resin particle dispersion of the present invention, addition polymerization resin particle dispersions prepared using conventionally known emulsion polymerization and the like can be used together.

  Examples of addition polymerization monomers for preparing these resin particle dispersions include styrenes such as styrene and parachlorostyrene, vinyl naphthalene, vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, propion. Vinyl esters such as vinyl acrylate, vinyl benzoate, vinyl butyrate, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, 2-chloroethyl acrylate, Methylene aliphatic carboxylic esters such as phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide such as vinyl methyl ether, vinyl ethyl ether, vinyl Monomers having an N-containing polar group, such as N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone, methacrylic acid, acrylic Homopolymers and copolymers of vinyl monomers such as vinyl carboxylic acids such as acid, cinnamic acid and carboxyethyl acrylate, and various waxes can also be used.

  In the case of addition polymerization monomers, emulsion polymerization can be carried out using an ionic surfactant or the like to produce a resin particle dispersion, and in the case of other resins, it is oily and the solubility in water is compared. If it is soluble in a low solvent, the resin is dissolved in those solvents and dispersed in an aqueous medium with a disperser such as a homogenizer together with an ionic surfactant or polymer electrolyte, and then heated or decompressed. Then, the resin particle dispersion can be obtained by evaporating the solvent.

  After the aggregation step, in the fusion step (fusion / unification step), the resin particles are heated to a temperature above the glass transition point or above the melting point to fuse and coalesce the aggregate particles. The toner can be obtained by washing and drying.

  In addition, after completion of the fusion process, desired toner particles are obtained through an arbitrary washing process, solid-liquid separation process, and drying process. In consideration of charging properties, the washing process should be sufficiently washed with ion exchange water. Is desirable. Moreover, although there is no restriction | limiting in particular in a solid-liquid separation process, From the point of productivity, suction filtration, pressure filtration, etc. are suitable. Further, the drying process is not particularly limited, but freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity.

Hereinafter, constituent components of the toner (raw materials used in the production method) will be described.
First, the following can be used as the colorant. Examples of the black pigment include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, nonmagnetic ferrite, and magnetite.
Examples of yellow pigments include yellow lead, zinc yellow, yellow iron oxide, cadmium yellow, chrome yellow, hansa yellow, hansa yellow 10G, benzidine yellow G, benzidine yellow GR, sren yellow, quinoline yellow, permanent yellow NCG and the like. be able to.
Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, benzidine orange G, indanthrene brilliant orange RK, and indanthrene brilliant orange GK.
Red pigments include Bengala, Cadmium Red, Red Plum, Mercury Sulfide, Watch Young Red, Permanent Red 4R, Risor Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Rhodamine B Lake, Lake Red C , Rose Bengal, Eoxin Red, Alizarin Lake and the like.
Blue pigments include bitumen, cobalt blue, alkali blue rake, Victoria blue rake, fast sky blue, induslen blue BC, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxare. Rate.
Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake.
Examples of the green pigment include chromium oxide, chromium green, pigment green, malachite green lake, final yellow green G, and the like.
Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide.
Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white.
Examples of the dye include various dyes such as basic, acidic, dispersed, and direct dyes, such as nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

  These colorants are used alone or in combination. With respect to these colorants, for example, a dispersion of colorant particles can be prepared using a media type dispersing machine such as a rotary shearing homogenizer, a ball mill, a sand mill, or an attritor, or a high-pressure opposed collision type dispersing machine. Further, these colorants can be dispersed in an aqueous system by a homogenizer using a polar surfactant.

  The colorant is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner.

  The colorant can be added in the range of 4 to 15% by weight with respect to the total weight of the toner constituting solids. When a magnetic material is used as the black colorant, 12 to 240% by weight can be added unlike other colorants.

  The blending amount of the colorant is a necessary amount for securing the color developability at the time of fixing. Moreover, OHP transparency and color developability can be ensured by setting the center diameter (median diameter) of the colorant particles in the toner to 100 to 330 nm.

  The center diameter (median diameter) of the colorant particles was measured, for example, with a laser diffraction particle size distribution measuring apparatus (LA-920, manufactured by Horiba, Ltd.).

  Further, when used as a magnetic toner, magnetic powder may be contained. Specifically, a material that is magnetized in a magnetic field is used, but a ferromagnetic powder such as iron, cobalt, or nickel, or a compound such as ferrite or magnetite is used. When obtaining toner in the aqueous phase, it is necessary to pay attention to the aqueous phase migration of the magnetic material, and it is preferable to modify the surface of the magnetic material in advance, for example, to perform a hydrophobic treatment or the like.

  In addition, magnetic materials such as ferrite, magnetite, reduced iron, cobalt, nickel, manganese and other metals, alloys, and compounds containing these metals are used as internal additives, and quaternary ammonium salt compounds, nigrosine as charge control agents. Various charge control agents, such as dyes consisting of complexes of aluminum compounds, aluminum, iron, chromium, and triphenylmethane pigments, can be used, but the ionic strength that affects the aggregation and temporary stability From the viewpoints of control of wastewater and reduction of wastewater contamination, materials that are difficult to dissolve in water are suitable.

  Specific examples of the release agent include, for example, various ester waxes, low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene, silicones that show a softening point by heating, oleic acid amide, erucic acid amide, ricinoleic acid amide, stearic acid Fatty acid amides such as amides, plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil, animal waxes such as beeswax, montan wax, ozokerite, ceresin, paraffin Examples thereof include mineral-based and petroleum-based waxes such as wax, microcrystalline wax, microcrystalline wax, Fischer-Tropsch wax, and modified products thereof.

  These waxes are hardly dissolved in a solvent such as toluene at room temperature or very little even if dissolved.

  These waxes are dispersed in an aqueous medium together with a polymer electrolyte such as an ionic surfactant, polymer acid or polymer base, heated above the melting point, and have a strong shearing ability and pressure discharge type. It can be dispersed in the form of particles with a disperser (Gorin homogenizer, manufactured by Gorin Co., Ltd.) to produce a dispersion of particles of 1 μm or less.

  It is desirable to add the release agent in the range of 5 to 25% by weight with respect to the total weight of the toner constituting solids, in order to ensure the peelability of the fixed image in the oilless fixing system.

  In addition, the particle diameter of the release agent particle dispersion was measured, for example, with a laser diffraction particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.). In addition, when using a release agent, after the resin particles, colorant particles, and release agent particles are aggregated, it is possible to add resin particle dispersion to adhere the resin particles to the surface of the aggregated particles. It is desirable from the viewpoint of securing the property.

The cumulative volume average particle diameter D ₅₀ of the toner obtained by the method for producing an electrostatic charge developing toner of the present invention is in the range of 3.0 to 9.0 μm, preferably in the range of 3.0 to 5.0 μm. When D ₅₀ is _less than 3.0 μm, the adhesion is increased and the developability may be lowered. On the other hand, if it exceeds 9.0 μm, the resolution of the image may deteriorate.

  Further, the volume average particle size distribution index GSDv of the obtained toner is preferably 1.30 or less. When GSDv exceeds 1.30, the resolution is deteriorated, which may cause image defects such as toner scattering and fogging.

Here, the cumulative volume average particle size D ₅₀ and the average particle size distribution index are, for example, the particle size distribution measured by a measuring instrument such as Coulter Counter TAII (manufactured by Nikka Kisha Co., Ltd.), Multisizer II (manufactured by Nikka Kisha Co., Ltd.), or the like. The particle size range (channel) divided based on the volume and number are cumulative distributions starting from the small diameter side, and the particle size that is 16% cumulative is the volume D _16v , the number D _16P , and the particle that is 50% cumulative The diameter is _defined as a volume D _50v and a number D _50P , and the particle diameter at a cumulative 84% is defined as a volume D _84v and a number D _84P . Using these, the volume average particle size distribution index (GSDv) is calculated as (D _84v / D _16V ) ^1/2 and the number average particle size distribution index (GSDp) is calculated as (D _84P / D _16P ) ^1/2 .

The shape factor SF1 of the obtained toner is in the range of 100 to 140, preferably 110 to 135, from the viewpoint of image formability. The shape factor SF1 is obtained as follows. First, an optical microscope image of the toner dispersed on the slide glass is taken into a Luzex image analyzer through a video camera, and the peripheral length (ML) and the projection area (A) of 50 or more toners are measured. Multiplier / projection area = ML ² / A) was defined as the toner shape factor SF1.

  The obtained toner is dried in the same manner as a normal toner for the purpose of imparting fluidity and improving cleaning properties, and then inorganic particles such as silica, alumina, titania and calcium carbonate, and resins such as vinyl resins, polyesters and silicones. The particles can be added to the surface of the toner particles while being sheared in a dry state.

  In addition, when adhering to the toner surface in an aqueous medium, examples of inorganic particles include silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, etc. Can be used by dispersing with an ionic surfactant, polymer acid, or polymer base.

  The toner obtained by the method for producing an electrostatic charge developing toner of the present invention described above is used as an electrostatic charge developer. The developer is not particularly limited except that it contains the electrostatic image developing toner, and can have an appropriate component composition depending on the purpose. When the electrostatic image developing toner is used alone, it is prepared as a one-component electrostatic image developer, and when used in combination with a carrier, it is prepared as a two-component electrostatic image developer.

  The electrostatic charge developer (electrostatic charge developing toner) can be used in an image forming method of a normal electrostatic charge developing method (electrophotographic method). Specifically, the image forming method of the present invention includes, for example, an electrostatic latent image forming step, a toner image forming step, a transfer step, and a cleaning step. Each of the above steps is a general step per se, and is described in, for example, JP-A-56-40868 and JP-A-49-91231. The image forming method of the present invention can be carried out using an image forming apparatus such as a copier or a facsimile machine known per se. The electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrostatic latent image carrier. The toner image forming step is a step of developing the electrostatic latent image with a developer layer on a developer carrier to form a toner image. The developer layer is not particularly limited as long as it contains the electrostatic image developer of the present invention containing the electrostatic image developing toner of the present invention. The transfer step is a step of transferring the toner image onto a transfer body. The cleaning step is a step of removing the electrostatic charge image developer remaining on the electrostatic latent image carrier. In the image forming method of the present invention, an embodiment that further includes a recycling step is preferable. The recycling step is a step of transferring the electrostatic charge image developing toner collected in the cleaning step to a developer layer. The image forming method including the recycling step can be performed using an image forming apparatus such as a toner recycling system type copying machine or facsimile machine. The present invention can also be applied to a recycling system in which the cleaning process is omitted and toner is collected simultaneously with development.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited at all.

  The toner of this example was prepared by preparing the following resin particle dispersion, colorant particle dispersion, and release agent particle dispersion, respectively, and mixing and stirring them at a predetermined ratio, while polymerizing a metal salt. Is added and ionically neutralized to form agglomerated particles. Next, inorganic hydroxide is added to adjust the pH of the system from weakly acidic to neutral, and then the mixture is heated to a temperature equal to or higher than the glass transition point of the resin particles to fuse and unite. After completion of the reaction, a desired toner is obtained through sufficient washing, solid-liquid separation, and drying processes. Hereinafter, each preparation method is demonstrated.

(Preparation of resin particle dispersion (1))
-Dodecylbenzenesulfonic acid: 36 parts by weight-1,9 nonanediol: 80 parts by weight-1, 10 decamethylene dicarboxylic acid: 115 parts by weight-Ion exchange water: 1000 parts by weight

  According to the above composition, first, dodecylbenzenesulfonic acid, 1,9 nonanediol, and 1,10 decamethylene dicarboxylic acid were mixed, heated to 120 ° C. and melted, and then this oil-based solution was heated to 95 ° C. The mixture was poured into the exchanged water, and immediately after that, it was emulsified with a homogenizer (IKA Corporation, Ultra Tarrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 5 minutes, and then the emulsion was maintained at 70 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (1) having a particle central diameter (median diameter) of 400 nm, a melting point of 70 ° C., a weight average molecular weight of 5500, and a solid content of 18% was obtained.
The particles of the resin particle dispersion (1) had a median particle ratio of 0.03 μm or less or 5.0 μm or more (hereinafter referred to as large / small particle total ratio) of 1.2%.

(Preparation of resin particle dispersion (2))
-Dodecylbenzenesulfonic acid: 36 parts by weight-1,6 hexanediol: 59 parts by weight-Sebacic acid: 101 parts by weight-Ion exchange water: 1000 parts by weight

  In accordance with the above composition, first, dodecylbenzenesulfonic acid, 1,6 hexanediol, and sebacic acid are mixed, heated to 140 ° C. and melted, and then this oil-based solution is put into ion-exchanged water heated to 95 ° C. Immediately after that, the mixture was emulsified with a homogenizer (manufactured by IKA, Ultra Tarrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 5 minutes, and then the emulsion was maintained at 70 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (2) having a particle central diameter (median diameter) of 720 nm, a melting point of 69 ° C., a weight average molecular weight of 4500, and a solid content of 16% was obtained.
The particles of the resin particle dispersion (2) had a large / small particle ratio of 4.4%.

(Preparation of resin particle dispersion (3))
-Dodecyl sulfate: 30 parts by weight-1,9 nonanediol: 80 parts by weight-Azelaic acid: 94 parts by weight-Ion exchange water: 1000 parts by weight

  According to the above formulation, first, dodecyl sulfate, 1,9 nonanediol, and azelaic acid are mixed, heated to 110 ° C. and melted, and then this oil-based solution is put into ion-exchanged water heated to 95 ° C., Immediately thereafter, the mixture was emulsified with a homogenizer (manufactured by IKA, Ultra Tarrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 5 minutes, and then the emulsion was maintained at 70 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (3) having a median particle diameter (median diameter) of 220 nm, a melting point of 55 ° C., a weight average molecular weight of 7500, and a solid content of 17% was obtained.
The particles of the resin particle dispersion (3) had a large / small particle overall ratio of 0.5%.

(Preparation of resin particle dispersion (4))
・ Isopropylbenzenesulfonic acid: 25 parts by weight ・ Terephthalic acid: 46 parts by weight ・ Polyoxyethylene (2,4) -2,2-bis (4-hydroxyphenyl) propane: 34 parts by weight ・ Ethylene glycol: 20 parts by weight Ion exchange water: 500 parts by weight

  In accordance with the above formulation, isopropylbenzene sulfonic acid, terephthalic acid, polyoxyethylene (2,4) -2,2-bis (4-hydroxyphenyl) propane, and ethylene glycol were mixed, heated to 110 ° C. and melted, This oil-based solution was poured into ion-exchanged water and emulsified with a homogenizer (IKA, Ultra Tarrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 5 minutes, and then the emulsion was maintained at 90 ° C. in a flask while stirring and held for 20 hours.

As a result, an amorphous polyester resin particle dispersion (4) having a particle center diameter (median diameter) of 520 nm, a glass transition point of 55 ° C., a weight average molecular weight of 4500, and a solid content of 14% was obtained.
The particles of the resin particle dispersion (4) had a large / small particle ratio of 2.3%.

(Preparation of resin particle dispersion (5))
-Scandium dodecylbenzenesulfonate (rare earth-containing catalyst): 36 parts by weight-1,9 nonanediol: 80 parts by weight-1, 10 decamethylene dicarboxylic acid: 115 parts by weight-Ion exchange water: 1000 parts by weight

  According to the above formulation, scandium dodecylbenzenesulfonate (rare earth-containing catalyst), 1,9 nonanediol, and 1,10 decamethylene dicarboxylic acid were mixed, heated to 120 ° C. and melted, and then this oil-based solution was heated to 95 ° C. Then, the mixture was put into an aqueous medium heated to 5 and immediately emulsified with a homogenizer (manufactured by IKA, Ultra Tarrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 5 minutes, and then the emulsion was maintained at 80 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (5) having a particle central diameter (median diameter) of 370 nm, a melting point of 70 ° C., a weight average molecular weight of 4900, and a solid content of 18% was obtained.
The particles of the resin particle dispersion (5) had a large / small particle ratio of 1.8%.

(Preparation of resin particle dispersion (6))
Dodecylbenzenesulfonic acid: 12 parts by weight Lipase (from Pseudomonas genus: enzyme catalyst): 50 parts by weight 1,9 nonanediol: 80 parts by weight 1,10 decamethylenedicarboxylic acid: 115 parts by weight 1000 parts by weight

  According to the above formulation, dodecylbenzenesulfonic acid, lipase, 1,9 nonanediol, and 1,10 decamethylene dicarboxylic acid are first mixed, heated to 120 ° C. and melted, and then this oil-based solution is heated to 85 ° C. Immediately after that, the mixture was emulsified with a homogenizer (IKA, Ultra Tarrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 5 minutes, and then the emulsion was maintained at 80 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (6) having a particle center diameter (median diameter) of 1070 nm, a melting point of 69 ° C., a weight average molecular weight of 4500, and a solid content of 20% was obtained.
The particles of the resin particle dispersion (6) had a large / small particle ratio of 8.8%.

(Preparation of resin particle dispersion (7): for comparison)
-Dodecylbenzenesulfonic acid: 18 parts by weight-1,9 nonanediol: 80 parts by weight-1, 10 decamethylene dicarboxylic acid: 115 parts by weight-Ion exchange water: 1000 parts by weight

  In accordance with the above formulation, first, 1,9 nonanediol and 1,10 decamethylene dicarboxylic acid were mixed, heated to 120 ° C. and melted, then poured into room temperature ion-exchanged water in which dodecylbenzenesulfonic acid was dissolved, and homogenizer ( The emulsion was emulsified with IKA (Ultra Turrax) for 1 minute. Thereafter, the emulsion was maintained at 60 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (7) having a particle central diameter (median diameter) of 2100 nm, a melting point of 69 ° C., a weight average molecular weight of 3500, and a solid content of 18% was obtained.
The particles of the resin particle dispersion (7) had a large / small particle ratio of 10.8%.

(Preparation of resin particle dispersion (8): for comparison)
-Dodecylbenzenesulfonic acid: 36 parts by weight-1,4 butanediol: 45 parts by weight-Azelaic acid: 94 parts by weight-Ion exchange water: 1000 parts by weight

  According to the above composition, azelaic acid and 1,4 butanediol were mixed, heated to 110 ° C. and melted, then poured into ion-exchanged water heated to 95 ° C. in which dodecylbenzenesulfonic acid was dissolved, and homogenizer (manufactured by IKA). , Ultra Turrax) for 5 minutes. Thereafter, the mixture was further emulsified in an ultrasonic bath for 30 minutes, and then the emulsion was maintained at 70 ° C. in a flask while stirring and held for 15 hours.

As a result, a crystalline polyester resin particle dispersion (8) having a particle central diameter (median diameter) of 25 nm, a melting point of 48 ° C., a weight average molecular weight of 6500, and a solid content of 15% was obtained.
The particles of the resin particle dispersion (8) had a large / small particle ratio of 12%.

(Preparation of resin particle dispersion (9): non-crystalline vinyl resin latex)
-Styrene: 460 parts by weight-n-butyl acrylate: 140 parts by weight-Acrylic acid: 12 parts by weight-Dodecanethiol: 9 parts by weight

  According to the above formulation, each component was mixed and dissolved to prepare a solution. On the other hand, 12 parts by weight of an anionic surfactant (manufactured by Rhodia, Dowfax) was dissolved in 250 parts by weight of ion-exchanged water, and the solution was added and dispersed and emulsified in a flask (monomer emulsion A). Furthermore, 1 part by weight of an anionic surfactant (manufactured by Rhodia, Dowfax) was dissolved in 555 parts by weight of ion-exchanged water and charged into a polymerization flask. The polymerization flask is sealed, a reflux tube is installed, and the polymerization flask is heated to 75 ° C. with a water bath while being slowly stirred while injecting nitrogen.

  Next, 9 parts by weight of ammonium persulfate was dissolved in 43 parts by weight of ion-exchanged water and dropped into the polymerization flask through a metering pump over 20 minutes, and then the monomer emulsion A was also passed through the metering pump. Add dropwise over 200 minutes.

  Thereafter, the polymerization flask is kept at 75 ° C. for 3 hours while continuing the slow stirring to complete the polymerization.

As a result, an anionic resin particle dispersion (9) having a median particle diameter (median diameter) of 210 nm, a glass transition point of 53.5 ° C., a weight average molecular weight of 31,000, and a solid content of 42% was obtained.
The particles of the resin particle dispersion (9) had a large / small particle ratio of 0.2%.

(Preparation of resin particle dispersion (10))
0.05 mol% of dibutyltin oxide was added to 40 parts by weight of 1,9 nonanediol and 57.5 parts by weight of 1,10 decamethylene dicarboxylic acid, and the mixture was stirred at 200 ° C. in a flask equipped with a stirring blade. Then, polymerization was allowed to proceed for 6 hours under reduced pressure to obtain a crystalline polyester resin having a weight average molecular weight of 6200 and a melting point of 69 ° C. By adding 460 g of ion-exchanged water in which 3.2 g of sodium dodecylbenzenesulfonate is dissolved to 80 g of this resin, heating to 140 ° C. under pressure in a stainless steel flask, and simultaneously emulsifying with Ultra Turrax for 1 hour, A crystalline polyester resin particle dispersion was obtained.
As a result, a resin particle dispersion (10) having a particle central diameter (median diameter) of 450 nm, a melting point of 69 ° C., and a solid content of 15% was obtained.
The particles of the resin particle dispersion (10) had a large / small particle ratio of 4.5%.

(Preparation of colorant particle dispersion (1))
Yellow pigment (Daiichi Seika Co., Ltd., Y74): 50 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku, Neogen R): 5 parts by weight

  According to the above formulation, the components were mixed and dissolved, dispersed for 5 minutes with a homogenizer (IKA Corporation, Ultra Tarrax) for 10 minutes and an ultrasonic bath, a yellow colorant having a center diameter (median diameter) of 240 nm and a solid content of 21.5%. A particle dispersion (1) was obtained.

(Preparation of colorant particle dispersion (2))
In the preparation of the colorant particle dispersion liquid (1), it was prepared in the same manner as the colorant particle dispersion liquid (1) except that a cyan pigment (manufactured by Dainichi Seika Co., Ltd., copper phthalocyanine B15: 3) was used instead of the yellow pigment. Thus, a Cyan colorant particle dispersion (2) having a center diameter (median diameter) of 190 nm and a solid content of 21.5% was obtained.

(Preparation of colorant particle dispersion (3))
In the preparation of the colorant particle dispersion (1), except that a magenta pigment (manufactured by Dainichi Ink Chemical Co., PR122) was used instead of the yellow pigment, it was prepared in the same manner as the colorant particle dispersion (1). A colorant particle dispersion (3) having a center diameter (median diameter) of 165 nm and a solid content of 21.5% was obtained.

(Preparation of colorant particle dispersion (4))
In the preparation of the colorant particle dispersion (1), except that a black pigment (Cabot, carbon black) was used instead of the yellow pigment, the colorant particle dispersion (1) was prepared in the same manner as the colorant particle dispersion (1). A colorant particle dispersion (4) having a median diameter of 170 nm and a solid content of 21.5% was obtained.

(Preparation of release agent particle dispersion)
Paraffin wax (Nippon Seiwa Co., Ltd., HNP9; melting point 70 ° C.): 50 parts by weight Anionic surfactant (Rohdia Dow Fax): 5 parts by weight

  In accordance with the above formulation, the components were heated to 95 ° C. and sufficiently dispersed with a homogenizer (IKA, Ultra Turrax T50), then dispersed with a pressure discharge type homogenizer (Gorin homogenizer, Gorin), and the center diameter. A release agent particle dispersion having a median diameter of 180 nm and a solid content of 21.5% was obtained.

[Toner Reference Example 1]
(Preparation of toner particles)
Resin particle dispersion (1): 233 parts by weight (42 parts by weight of resin)
-Resin particle dispersion (9) 50 parts by weight (21 parts by weight of resin)
Colorant particle dispersion (1) 40 parts by weight (8.6 parts by weight of pigment)
-40 parts by weight of release agent particle dispersion (8.6 parts by weight of release agent)
-Polyaluminum chloride: 0.15 parts by weight-Ion exchange water: 300 parts by weight

  In accordance with the above formulation, the components (excluding the resin particle dispersion (9)) were thoroughly mixed and dispersed in a round stainless steel flask with a homogenizer (manufactured by IKA, Ultra Turrax T50), and then the flask was heated with an oil bath for heating. The mixture was heated to 42 ° C. with stirring and maintained at 42 ° C. for 60 minutes, and then 50 parts by weight (21 parts by weight of resin) of the resin particle dispersion (9) was added and gently stirred.

  Thereafter, the pH in the system was adjusted to 6.0 with a 0.5 mol / liter sodium hydroxide aqueous solution, and then heated to 95 ° C. while stirring was continued. During the temperature increase up to 95 ° C, the pH in the system usually drops to 5.0 or less, but here, an aqueous sodium hydroxide solution is added dropwise to keep the pH from dropping to 5.5 or less. did.

  After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, and then solid-liquid separated by Nutsche suction filtration. And it re-dispersed in 3 liters of ion-exchanged water at 40 ° C. and stirred and washed at 300 rpm for 15 minutes. This washing operation was repeated 5 times, followed by solid-liquid separation by Nutsche suction filtration, and then vacuum drying for 12 hours to obtain toner particles.

When the particle size of the toner particles was measured with a Coulter counter, the cumulative volume average particle size D ₅₀ was 4.6 μm, and the volume average particle size distribution index GSDv was 1.20. The shape factor SF1 of the toner particles obtained from the shape observation by Luzex was 130 potato shapes.

  1.2 parts by weight of hydrophobic silica (manufactured by Cabot, TS720) was added to 50 parts by weight of the toner particles, and mixed with a sample mill to obtain an externally added toner.

  Then, using a ferrite carrier having an average particle diameter of 50 μm coated with 1% of polymethyl methacrylate (manufactured by Soken Chemical Co., Ltd.), the externally added toner is weighed so that the toner concentration becomes 5%. A developer was prepared by stirring and mixing for a minute.

(Evaluation of toner)
Using the above developer, Fuji Xerox's DocuCenterColor500 modified machine uses Fuji Xerox J-coated paper as the transfer paper, and the process speed is adjusted to 180 mm / sec, and the toner fixing property is examined. The oil-less fixability by the PFA tube fixing roll is good, and the minimum fixing temperature (this temperature is determined by image rubbing by image cloth rubbing) is 120 ° C. or higher, and the image exhibits sufficient fixability. At the same time, it was confirmed that the transfer paper was peeled off without any resistance. The surface gloss of the image at a fixing temperature of 140 ° C. was as good as 65%, both developability and transferability were good, and there was no image defect and a high quality and good image (◯) was shown. The occurrence of hot offset was not observed even at a fixing temperature of 200 ° C.

  Further, before the preparation of the toner, the stability of the resin particle dispersion (1) used was measured by weighing 100 g of the resin particle dispersion into a 300 ml stainless beaker, and after shear homogenization with an IKA Ultra Tarax T50 in the beaker for 1 minute. When the resin particle dispersion is filtered through a 77-micron nylon mesh and examined by the method of observing the presence or absence of aggregation (shear homogenization method), the formation of aggregates is not observed at all and the dispersion is in a stable state. (◎).

[Toner Reference Example 2]
In Reference Example 1, the resin particle dispersion (1) is changed to the resin particle dispersion (2) and the colorant particle dispersion (1) is changed to the colorant particle dispersion (2) according to the blending amount in Table 1. Then, toner particles were obtained in the same manner as in Reference Example 1 except that the pH during heating at 95 ° C. was maintained at 5.0.

The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.40 μm, and the volume average particle size distribution index GSDv is 1.19. The shape factor SF1 was slightly spherical with 124.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. It was confirmed that the minimum fixing temperature was 115 ° C. or higher, the image showed sufficient fixability, and the transfer paper was peeled off without any resistance. The surface gloss of the image at a fixing temperature of 150 ° C. was as good as 70%, both developability and transferability were good, and there was no image defect and a high quality and good image (◯) was shown. Also, no hot offset was observed at a fixing temperature of 200 ° C.

  Further, the stability of the used resin particle dispersion (2) was examined by the above-described shear homogenization method before the preparation of the toner. As a result, no aggregation was observed and the stability was good (◎).

[Toner Reference Example 3]
In Reference Example 1, the resin particle dispersion (1) was changed to the resin particle dispersion (3) according to the blending amount in Table 1, and the resin particle dispersion (9) was changed to the resin particle dispersion (4). Toner particles were obtained in the same manner as in Reference Example 1 except that the colorant particle dispersion (2) was changed to the colorant particle dispersion (3) and the amount of polyaluminum chloride was 0.12 parts by weight.

The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.20 μm, the volume average particle size distribution index GSDv is 1.22, the shape factor SF1 is 119, and the toner particles are spherical.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. It was confirmed that the minimum fixing temperature was 100 ° C. or higher, the image showed sufficient fixability, and the transfer paper was peeled off without any resistance. The surface gloss of the image at a fixing temperature of 150 ° C. was as good as 85%, both developability and transferability were good, and an extremely high quality image (◎) was obtained without image defects. No occurrence of hot offset was observed even at a fixing temperature of 200 ° C.

  Further, the stability of the resin particle dispersions (3) and (4) used before the preparation of the toner was examined by the shear homogenization method described above. Met.

[Toner Example 4]
In Reference Example 1, toner particles were obtained in the same manner as in Reference Example 1, except that the resin particle dispersion (1) was changed to the resin particle dispersion (5) according to the blending amount in Table 1.

The toner particles had a cumulative volume average particle diameter D ₅₀ of 3.92 μm, a volume average particle size distribution index GSDv of 1.22, and a shape factor SF1 of 135 potato.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. It was confirmed that the minimum fixing temperature was 110 ° C. or higher, the image showed sufficient fixability, and the transfer paper was peeled off without any resistance. The surface gloss of the image at a fixing temperature of 150 ° C. was as good as 55%, both developability and transferability were good, and there was no image defect and a high quality and good (◯) image was shown. The occurrence of hot offset was not observed even at a fixing temperature of 200 ° C.

  Further, when the stability of the used resin particle dispersion (5) was examined by the above-described shear homogenization method before toner preparation, no aggregation was observed and the stability was good (◎).

[Toner Reference Example 5]
In Reference Example 2, the resin particle dispersion (2) was changed to the resin particle dispersion (6) in accordance with the blending amount shown in Table 1, and all the resin particle dispersions were used as the resin particle dispersion (6). Toner particles were obtained in the same manner as in Reference Example 1 except that (9) was not used.

The cumulative volume average particle diameter D ₅₀ of the toner particles is 3.50 μm, the volume average particle size distribution index GSDv is 1.25, and the shape factor SF1 is 120.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. It was confirmed that the minimum fixing temperature was 90 ° C. or higher, the image showed sufficient fixability, and the transfer paper was peeled off without any resistance. The surface gloss of the image at a fixing temperature of 150 ° C. was as good as 55%, both developability and transferability were good, and there was no image defect and a high quality and good image (◯) was shown. At the fixing temperature of 200 ° C., some hot offset was observed.

  Further, when the stability of the used resin particle dispersion (6) was examined by the above-described shear homogenization method before the toner was prepared, the occurrence of agglomeration was slightly observed but there was no problem (◯). It was almost stable.

[Toner Comparative Example 1]
In Reference Example 2, the resin particle dispersion (2) was changed to the resin particle dispersion (7) in accordance with the blending amount shown in Table 1, and toner particles were obtained in the same manner as in Reference Example 2.

The toner particles had a cumulative volume average particle diameter D ₅₀ of 5.50 μm, a volume average particle size distribution index GSDv of 1.30, a shape factor SF1 of 135 and a potato shape.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. The image was satisfactory and the minimum fixing temperature was 120 ° C. or higher, and the image showed sufficient fixability. However, the peeled state of the transfer paper was poor, and waving and winding after fixing of the paper were confirmed. Hot offset was observed from the fixing temperature of 180 ° C. Occurrence of coarse powder was observed in the toner, and defects such as white spots were observed in the image (×).

  Further, when the stability of the resin particle dispersion (7) used was examined by the shear homogenization method described above before the toner was prepared, a large amount of aggregation was observed (×).

[Toner Comparative Example 2]
In Reference Example 2, the resin particle dispersion (2) was changed to the resin particle dispersion (8) in accordance with the blending amount shown in Table 1, and toner particles were obtained in the same manner as in Reference Example 2.

The accumulated volume average particle diameter D ₅₀ of the toner particles 5.70Myuemu, volume average particle size distribution index GSDv of 1.26, a shape factor SF1 was 120 spherical.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. The image was not good, the minimum fixing temperature was 90 ° C. or more, and the image showed a sufficient fixing property, but the transfer paper was not peeled well, and undulation and winding after fixing of the paper were confirmed. In addition, significant hot offset was observed from a fixing temperature of 140 ° C., and there were image defects (×).

  Further, before the toner was prepared, the stability of the resin particle dispersion (8) used was examined by the shear homogenization method described above, and a slight occurrence of aggregation was observed (Δ).

[Toner Comparative Example 3]
In Reference Example 2, the resin particle dispersion (2) was changed to the resin particle dispersion (10) in accordance with the blending amount shown in Table 1, and toner particles were obtained in the same manner as in Reference Example 2.

The cumulative volume average particle diameter D ₅₀ of the toner particles is 5.95 μm, the volume average particle size distribution index GSDv is 1.40, and the shape factor SF1 is 118.

Using these toner particles, an externally added toner was obtained in the same manner as in Reference Example 1, and a developer was further prepared. The toner fixability was examined in the same manner as in Reference Example 1. As a result, oil-less fixability with a PFA tube fixing roll was investigated. The image was not good, the minimum fixing temperature was 130 ° C. or higher, and the image showed a sufficient fixing property, but the peeled-off state of the transfer paper was poor, and undulation and wrapping after fixing of the paper were confirmed. In addition, significant hot offset was observed from a fixing temperature of 160 ° C. In addition, solid image roughness and toner scattering on fine lines were observed, which was unsatisfactory (×).

  Further, when the stability of the resin particle dispersion (10) used was examined by the shear homogenization method described above before the toner was prepared, agglomeration was remarkable and a considerable amount of agglomerate remained on the nylon mesh. (×).

The results of these Examples, Reference Examples and Comparative Examples are summarized in Table 1. In the table, the evaluation criteria for the stability of the resin particle dispersion are “◎” indicating no occurrence of agglomeration, “○” indicating a slight occurrence but no problem, Δ indicating a slight occurrence, and “×”. A large amount of aggregation occurred. The evaluation criteria for image quality were “品質” being extremely good, “◯” being good, and “x” being image defect occurrence.

  From these results, as in this example, the median diameter of the polycondensation resin particles emulsified and dispersed by direct polycondensation in an aqueous medium is set within a predetermined range, so that the toner using the polycondensation resin as a raw material can be efficiently used. It can be seen that, in addition to making it possible to manufacture the toner, it is possible to dramatically improve the image quality fixing performance of the toner.

  On the other hand, even in the case of polycondensation resin particles emulsified and dispersed by direct polycondensation in an aqueous medium as in the comparative example, the median diameter is out of the predetermined range, or a polycondensation resin is obtained separately. After that, in the case of polycondensation resin particles dispersed in an aqueous medium, it can be seen that the toner characteristics (image quality and fixability) are worse than those of the examples even when the median diameter is within a predetermined range. .

Claims (2)

Using a scandium catalyst having an alkylbenzene sulfonate structure as a polycondensation catalyst, as a polycondensation monomer that is a raw material for polyester particles, polycondensation of at least a polyvalent carboxylic acid and a polyol in an aqueous medium, A method for producing a resin particle dispersion comprising forming polyester particles dispersed at 0.05 μm or more and 2.0 μm or less. A method for producing an electrostatic charge developing toner comprising: a step of aggregating the resin particles in a dispersion in which the resin particles are dispersed to obtain aggregated particles; and a step of heating and aggregating the aggregated particles. And
A method for producing an electrostatic charge developing toner, wherein at least one of the dispersions in which the resin particles are dispersed is obtained by the method for producing a resin particle dispersion according to claim 1 .