JP2009020487A - Toner, method for manufacturing toner, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small particle diameter toner or a two-component developer, which has sharp particle size distribution without requiring a classification step, attains a long service life, and prevents the occurrence of voids and spattering in transfer. <P>SOLUTION: The toner contains core particles formed by aggregating at least resin particles, colorant particles and wax particles in an aqueous medium, wherein a dispersant used in a colorant particle dispersion with colorant particles dispersed therein, contains a polypropylene glycol ethyleneoxide addition product, and the dispersant used in the colorant particle dispersion contains the polypropylene glycol ethyleneoxide addition product and a polymeric dispersant. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a copying machine, a laser printer, plain paper FAX, a color PPC, a color laser printer, a color FAX, a toner used in these multifunction peripherals, a toner manufacturing method, and an image forming apparatus.

  In recent years, image forming apparatuses such as printers are shifting from the purpose of office use to personal use, and there is a demand for a technology that realizes miniaturization, high speed, high image quality, and colorization. Therefore, a tandem color process that enables high-speed output of color images and a clear color image with high glossiness and high translucency, and non-offset characteristics, without using fixing oil to prevent offset during fixing. Oilless fixing is required. These functions need to be compatible at the same time, and improving the characteristics of the toner as well as the process is an important factor.

  In a color printer, in a fixing process, it is necessary to melt and mix color toners in a color image to increase translucency. When toner melting failure occurs, light scattering occurs on the surface or inside of the toner image, and the original color tone of the toner dye is impaired. In addition, in the portion where different color toners overlap, light does not enter the lower layer. Reproducibility decreases. Therefore, the toner needs to have a complete melting characteristic and a translucency so as not to disturb the color tone. Further, it is required to realize oilless fixing without using silicone oil or the like for the fixing roller. In order to make this possible, a configuration in which a release agent such as wax is added to a binder resin having sharp melt characteristics has been put into practical use.

  However, the problem with toners to which a release agent such as wax is added is that the cohesiveness of the toner tends to be strong, so that the toner image during transfer and transfer defects are prominent, and it is difficult to achieve both transfer and fixing. Become. In addition, when used as a two-component development, due to heat generation due to collision and friction between particles, or mechanical collision and friction between the particle and the developing device, it is easy to generate a spent where the low melting point component of the toner adheres to the carrier surface, The charging ability of the carrier is lowered, which hinders the extension of the developer life.

  The toner is generally composed of a resin component that is a binder resin, a pigment, a charge control agent, and, if necessary, an additive component such as a release agent. These materials are preliminarily mixed at an appropriate ratio, heated and kneaded by heat melting, finely pulverized by an airflow type impact plate method or the like, and finely powder classified to complete toner base particles. There has also been proposed a method in which toner base particles are prepared by a chemical polymerization method. Thereafter, an external additive such as hydrophobic silica is externally added to the toner base particles to complete the toner. In one-component development, the toner is composed only of toner, but a two-component developer can be obtained by mixing with toner and a carrier composed of magnetic particles.

  In the conventional kneading and pulverizing method, there is a limit to the particle size of the toner that can be actually produced economically and in performance. Therefore, a toner production method using various polymerization methods different from the kneading and pulverization method has been studied.

  In Patent Document 1 below, a toner comprising particles formed by polymerization and a coating layer made of fine particles formed by emulsion polymerization on the surface of the particles, and a water-soluble inorganic salt is added to the surface of the particles. A configuration for generating a coating layer of particles is described. Moreover, the structure which produces | generates the coating layer by a microparticle on the particle | grain surface by changing the pH of a solution is disclosed.

  In the following Patent Document 2, a step of preparing an aggregated particle dispersion by forming aggregated particles in a dispersion obtained by dispersing at least resin particles, a resin fine particle dispersion obtained by dispersing resin fine particles in the aggregated particle dispersion A method for producing a toner is disclosed, which includes a step of adhering and mixing the resin particles to form resin particles on the aggregated particles to form the adhered particles, and a step of heating and fusing the adhered particles. As the method of addition and mixing, for example, it is disclosed that it may be carried out gradually continuously or may be carried out stepwise by dividing into a plurality of times. And the effect which was excellent in the charging performance which suppressed generation | occurrence | production of a fine particle and the particle size distribution was sharp by adding and mixing the said resin fine particle (additional particle) is described.

  In the following Patent Document 3, the release agent contains at least one ester composed of at least one of a higher alcohol having 12 to 30 carbon atoms and a higher fatty acid having 12 to 30 carbon atoms, and the resin particles have a molecular weight. It is disclosed that by including at least two different types of resin particles, it is excellent in fixing property, coloring property, transparency, color mixing property and the like.

  In the following Patent Document 4, the content of the surfactant in the toner particles is 3 wt% or less, and an inorganic metal salt (for example, zinc chloride) having a charge of 2 or more is contained at 10 ppm or more and 1 wt% or less. A configuration for improving moisture absorption resistance formed by ionic crosslinking is disclosed. After the resin fine particle dispersion and the colorant dispersion are mixed and an aggregate dispersion is prepared using an inorganic metal salt, the mixture is heated above the glass transition point of the resin to fuse the aggregate to form a toner. . As a result, narrow particle size distribution small particle size toners having excellent charging characteristics, environmental dependence, cleaning properties and transfer properties are described.

  Patent Document 5 below discloses a toner having a shape factor of 100 to 137, forms an aggregate particle dispersion of resin fine particles and a colorant, and the obtained aggregate particle dispersion is used as a glass transition temperature ( Tg) or more, preferably Tg to Tg + 10 ° C. The temperature is increased to a temperature range of Tg to Tg + 10 ° C., for example, after the aggregate particles are grown to the desired toner particle diameter over 2 hours, the aggregation is stopped and further A configuration in which toner particles having a shape factor in the range of 100 to 137 are formed by heating to the same temperature and fusing and coalescing the surfaces of the aggregate particles within 10 hours is disclosed.

  In Patent Document 6 below, the toner comprises at least a binder resin, a colorant, and two or more release agents having different melting points, and the volume average particle diameter D50v of the toner is in the range of 3 to 8 μm. The particle size distribution index GSDv is 1.25 or less, and the weight average molecular weight Mw of the binder resin is in the range of 6000 to 45000. Among the two or more release agents, the melting point α of the lowest melting point release agent is 90 to 115 ° C. And a composition in which the melting point of at least one other high-melting mold release agent is in the range of 1.3α to 2.1α ° C., the image is highly glossy, and the storage property is excellent. It describes the effect that documents can be obtained and excellent transparency can be obtained for OHP.

  In Patent Document 7 below, toner particles in which a resin layer (shell) formed by fusing resin particles by a salting-out / fusing method is formed on the surface of colored particles (core particles) containing a resin and a colorant. Disclosed is a configuration in which a dispersion of resin particles is added to a dispersion of colored particles to maintain a temperature above the glass transition temperature in succession to the salting-out / fusion process for obtaining colored particles. The amount of colorant present on the surface is small, and even if it is used for long-term image formation in a high-humidity environment, it does not cause changes in image density, fogging, and color due to changes in chargeability and developability. Is described.

  In Patent Document 8 below, in an electrostatic charge image developing toner including toner particles containing at least a resin and a colorant, the toner particles include a core containing resin A and at least one layer of resin B covering the core. A toner having a shell containing the toner and having a film thickness of 50 nm to 500 nm on the outermost surface layer of the shell is disclosed, and the effect of the toner for developing an electrostatic charge image having excellent offset resistance and good storage stability Is described.

  In the configuration in which these emulsified resin particles, wax particles, and pigment particles are aggregated to form particles, disclosure has been made regarding conditions such as an aggregating agent, temperature, and pH.

  However, when the balance of the aggregation speed of these particles is disturbed, for example, when the aggregation speed of the pigment is increased, the aggregation of the resin particles and the pigment particles proceeds rapidly, the wax is left behind, and the liquid remains cloudy. In some cases, particles in which only pigment is aggregated may remain.

  In addition, when a resin layer is further adhered to the core particles in which the resin particles, wax particles and pigment particles are aggregated to form a core-shell structure, if there is a large amount of wax on the surface of the core particles, the adhesion of the shell resin does not proceed, or there are many pigments. If present, the chargeability may be affected. As a result, the controllability of the shape of the toner particles is deteriorated, and the particle size distribution becomes broad, making it difficult to produce small particle size particles. In addition, a decrease in chargeability tends to cause a decrease in image quality such as omission or fog during transfer.

That is, it is important to form the core particles by adjusting the balance of the aggregation speed of the resin particles, the pigment particles, and the wax particles. However, the means for adjusting the balance of the aggregation speed to aggregate the core particles is not sufficiently disclosed. .
Japanese Unexamined Patent Publication No. 57-45558 Japanese Patent Laid-Open No. 10-073955 JP-A-10-301332 Japanese Patent Laid-Open No. 11-311877 Japanese Patent Laid-Open No. 2000-131876 JP 2004-198862 A JP 2002-116574 A JP 2004-191618 A

  A method of adding a certain amount or more of wax to improve fixability such as realization of oilless fixing is disclosed, but the wax is agglomerated in an aqueous medium to agglomerate with colorant particles and resin particles to form core particles. When the particles are produced, the particle diameter becomes coarser with the heat treatment time, and it tends to be difficult to produce small particles with a narrow particle size distribution.

  In addition, in order to avoid the coarsening of the particle diameter, the method of changing the aqueous temperature and stirring speed conversely prevents uniform mixing and aggregation of the resin particles, wax particles and pigment particles in the aqueous system, and in the aqueous system. There is a tendency that wax particles and pigment particles that remain without being taken into the core particles tend to be generated.

  During the agglomeration reaction, since the wax particles have high crystallinity, melting starts suddenly from a certain temperature. However, since the resin particles are amorphous, the rubber state continues in a certain temperature range. Also, the pigment particles are present as particles without melting. In such a state, if the agglomeration reaction between the melted wax particles and the pigment particles does not proceed uniformly, the particle size distribution of the produced core particles is widened, or particles with a large amount of wax and pigment are apt to be generated. There is a tendency.

  Also, floating wax particles and carbon black and other pigment particles that remain without being aggregated tend to cause a decrease in charge amount, an increase in toner adhesion to non-image areas, and filming on the photoreceptor or transfer body. Become. Further, when the dispersibility of the wax particles or pigment particles in the core particles is deteriorated, color turbidity is likely to occur in the toner image melted at the time of fixing, and the color developability of the toner becomes insufficient.

  In addition, a core-shell configuration is disclosed in which shell resin particles are fused to the surface of core particles (sometimes referred to as core particles) to obtain toner particles, but a shell in which shell resin particles are dispersed in a dispersion of core particles. In the method of mixing the resin dispersion and heating to form a shell, when the shell resin particles are fused to the core particles blended with the wax described above, the presence of the wax hinders the adhesion of the shell resin particles and the adhesion is difficult. In some cases, the shell resin particles do not proceed, or once the shell resin particles adhere to the core particles, the shell resin particles may be detached from the core particles due to the releasing action of the wax when the wax melts in the subsequent heat treatment step.

  Further, the carbon black particles exhibit characteristics close to inorganic, compared with other organic pigments such as phthalocyanine, quinacridone, and azo, and the carbon black particles have a certain DBP oil absorption characteristic. When heat treatment is carried out in an aqueous medium to form core particles by agglomerating with resin particles and wax particles, when the agglomeration reaction proceeds with the heating temperature being higher than the melting point of the wax, the wax is in a molten state, and carbon black particles Is the state of powder. The carbon black particles having a certain DBP oil absorption property absorb (adsorb) the melted wax due to the oil absorption. As a result, gray particles in which carbon black particles and wax are coagulated and melted tend to be generated. Further, some of the particles are easily coarsened, and the balance of particles in the aqueous system is lost, so that floating wax particles and pigment particles that are not involved in aggregation tend to remain. If these agglomeration reactions do not proceed uniformly, depending on the conditions for agglomerating the particles, it may be difficult to arbitrarily adjust the shape of the toner to a certain shape. Stabilization of aggregation and shape adjustment is an important factor in image formation.

  In addition, when the wax melted in the carbon black particles is absorbed (adsorbed), the inherent low-temperature fixability and offset-resistant fixability functions of the wax may decrease, and the fixable temperature range may tend to decrease.

  The agglomeration reaction between the carbon black particles having a certain DBP oil absorption characteristic in a powder state and the melted wax affects the core particle formation during the agglomeration reaction in an aqueous system, and also affects the fixability function of the wax. There is a tendency to influence.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a toner that can produce a toner having a small particle size having a sharp particle size distribution without a classification step, and a method for producing the toner.

  In addition, in oilless fixing without using oil in the fixing roller, a release agent such as wax is used in the toner to achieve low temperature fixing property, high temperature non-offset property, paper separating property from the fixing roller, etc. and high temperature state. An object of the present invention is to provide a toner, a toner manufacturing method, and an image forming apparatus that achieve both storage stability during storage.

  It is another object of the present invention to provide a toner and a method for producing the toner that can prevent voids and scattering during transfer and can achieve high transfer efficiency.

The constitution of the present invention is a toner containing at least core particles formed by aggregating resin particles, colorant particles and wax particles, and used as a dispersant used in a colorant particle dispersion in which the colorant particles are dispersed. And a toner containing a polypropylene glycol ethylene oxide adduct.

  Further, the configuration of the present invention includes at least a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed in an aqueous medium. A step of mixing to produce a mixed solution, and a step of adding a flocculant to the mixed solution to agglomerate the resin particles, the colorant particles and the wax particles to produce core particles, This is a method for producing a toner in which a dispersant used for a colorant particle dispersion in which colorant particles are dispersed contains a polypropylene glycol ethylene oxide adduct.

  Polypropylene glycol ethylene is used as a dispersant used in the colorant particle dispersion in a toner configuration including core particles produced by mixing and aggregating each particle dispersion in which resin particles, colorant particles and wax particles are dispersed. By containing an oxide adduct, the problem of remaining wax particles and colorant particles remaining in the core particles without being agglomerated in the aqueous system is solved, and small particle size particles are generated with a narrow particle size distribution. be able to.

  In addition, by improving the dispersibility by relaxing the phenomenon that the colorant particles in the resin aggregate locally and the dispersion is localized, it is effective to improve the durability and charging stability in development characteristics. It is done.

  Further, the effect of improving the fixing property, offset resistance and storage stability can be obtained without deteriorating the fixing function of the wax.

  In addition, in the tandem color process where image forming stations with multiple photoconductors and development units are arranged side by side and the toner of each color is successively transferred to the transfer body, it is possible to prevent voids and reverse transfer during transfer. In addition, high transfer efficiency can be obtained.

(1) Polymerization and agglomeration step The resin particle dispersion is obtained by subjecting a vinyl monomer to a homopolymer or copolymer (vinyl-based) of a vinyl monomer by emulsion polymerization or seed polymerization in a surfactant. Resin) can be prepared by producing a dispersion liquid in which resin particles are dispersed in a surfactant. As the means, for example, a high-speed rotating emulsifier, a high-pressure emulsifier, a colloid emulsifier, a ball mill having a medium, a sand mill, a dyno mill, and the like are known per se.

  When the resin in the resin particle is a resin other than the homopolymer or copolymer of the vinyl monomer, the resin can be dissolved in an oily solvent having a relatively low solubility in water. Is dissolved in the oily solvent, and the solution is dispersed in water together with a surfactant and a polymer electrolyte using a disperser such as a homogenizer, and then the oily solvent is evaporated by heating or decompressing. A dispersion is prepared by dispersing resin particles other than vinyl resin in a surfactant.

  The colorant particle dispersion is prepared by adding colorant particles such as pigments in an aqueous system and dispersing them using the appropriate dispersing means described above.

  The wax particle dispersion is prepared by adding wax particles in an aqueous system and dispersing them using the appropriate dispersing means described above.

  The toner or toner production method according to the present invention includes at least a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax in which wax particles are dispersed in an aqueous medium. A toner containing core particles obtained by mixing and aggregating a particle dispersion. The dispersant used for the colorant particle dispersion includes a polypropylene glycol ethylene oxide adduct.

  Compared to the configuration using a conventional anionic or nonionic surfactant, the generation of gray particles can be eased, and the localized cohesiveness of the colorant particles in the resin can be suppressed. Allows formation. In addition, it is possible to suppress the generation of colorant particles that are not aggregated in the aqueous system and remain without being incorporated into the core particles, and to generate particles having a small particle size and a narrow particle size distribution.

  In addition, the agglomeration reaction between the resin particles, the wax particles and the colorant particles of this structure proceeds uniformly, and in the temperature rising process from room temperature to around 90 ° C., the melted wax particles and the colorant particles are aggregated only with each other. This has the effect of avoiding the formation of coarse particles.

  The amount of the polypropylene glycol ethylene oxide adduct based on the colorant particles is preferably 1 to 25 parts by weight with respect to 100 parts by weight of the colorant particles. Preferably it is 5-20 weight part, More preferably, it is 10-20 weight part.

  In particular, when carbon black is used as a pigment, the effect appears remarkably. The carbon black particles exhibit characteristics close to inorganic, compared to other organic pigments such as phthalocyanine, quinacridone, and azo, and the carbon black particles have a certain DBP oil absorption characteristic. When heat treatment is carried out in an aqueous medium to form core particles by agglomerating with resin particles and wax particles, when the agglomeration reaction proceeds with the heating temperature being higher than the melting point of the wax, the wax is in a molten state, and carbon black particles Is the state of powder. The carbon black particles having a certain DBP oil absorption characteristic absorb oil (adsorb) the melted wax due to its oil absorption. As a result, gray particles in which carbon black particles and wax are coagulated and melted may be easily generated. In addition, when the wax melted in the carbon black particles is absorbed (adsorbed), the inherent low-temperature fixability and offset-resistant fixability functions of the wax may decrease, and the fixable temperature range may decrease.

  Therefore, the colorant particles containing the polypropylene glycol ethylene oxide adduct can adjust the aggregation speed of the carbon black particles, and as a result, the effect of suppressing the generation of gray particles in which only the carbon black particles and the wax particles are aggregated and melted Is obtained.

  Moreover, it can relieve | distribute in the state which carbon black particle | grains solidified and aggregated in the core particle, and can disperse | distribute carbon black particle uniformly in a core particle. As a result, the fogging, which is the toner adhesion to the non-image area in the development, is improved, the durability is improved, and the transferability is improved. In addition, there is an effect on the dispersibility of the wax, and an effect of improving the fixing property is obtained.

  In the toner or the toner manufacturing method according to the present invention, it is also preferable to mix and use a polymer dispersant in addition to the above-mentioned polypropylene glycol ethylene oxide adduct as a dispersant used in the colorant particle dispersion.

  By mixing the polymer dispersant, the polymer dispersant promotes aggregation with the resin particles, and the polypropylene glycol ethylene oxide adduct promotes aggregation with the wax, thereby promoting a uniform aggregation reaction. It seems that an effect can be obtained in the generation of small-diameter particles in which particles and colorant particles are uniformly dispersed in the core particles.

  As the amount of the polypropylene glycol ethylene oxide adduct and the polymer dispersant with respect to the colorant particles, the polypropylene glycol ethylene oxide adduct is 1 to 25 weights with respect to 100 parts by weight of the colorant particles, and the polymer dispersant is 100 weights of the colorant particles. It is preferable to set it as 1-25 weight part with respect to a part.

More preferably, the polypropylene glycol ethylene oxide adduct is 5 to 25 parts by weight with respect to 100 parts by weight of the colorant particles, and the polymer dispersant is preferably 4 to 20 parts by weight with respect to 100 parts by weight of the colorant particles. More preferably, the polypropylene glycol ethylene oxide adduct is preferably 10 to 20 parts by weight based on 100 parts by weight of the colorant particles, and the polymer dispersant is preferably 5 to 15 parts by weight based on 100 parts by weight of the colorant particles. The blending amount of the glycol ethylene oxide adduct is preferably equal to or greater than the blending amount of the polymer dispersant. Furthermore, as the blending ratio, the weight blending ratio of the polypropylene glycol ethylene oxide adduct and the polymer dispersant is 1:10. It is preferable to set it as -10: 1. More preferably, the ratio is 2: 1 to 8: 1. More preferably, the ratio is 3: 1 to 5: 1.

  By containing a certain amount of the polymer-based dispersant, the aggregation rate can be adjusted, and the colorant particles in the core particles can be dispersed in an aggregated state and can be relaxed. It seems to be a ratio that can suppress the phenomenon that particles are localized and can exert an effect of being uniformly dispersed.

  Moreover, it is also preferable to mix and use a polymer-type dispersing agent with the polypropylene glycol ethylene oxide adduct mentioned above as a dispersing agent used for a wax particle dispersion.

  The amount of the polypropylene glycol ethylene oxide adduct and the polymer dispersant with respect to the wax particles is as follows: the polypropylene glycol ethylene oxide adduct is 2 to 20 parts by weight with respect to 100 parts by weight of the wax particles, and the polymer dispersant is 100 parts by weight with respect to the wax particles. It is preferable to set it as 1-15 weight part.

More preferably, the polypropylene glycol ethylene oxide adduct is 3 to 15 parts by weight with respect to 100 parts by weight of the wax particles, and the polymer dispersant is preferably 2 to 10 parts by weight with respect to 100 parts by weight of the wax particles. More preferably, the polypropylene glycol ethylene oxide adduct is preferably 5 to 12 parts by weight with respect to 100 parts by weight of the wax particles, and the polymer dispersant is 3 to 6 parts by weight with respect to 100 parts by weight of the wax particles. The blending amount of the oxide adduct is preferably equal to or greater than the blending amount of the polymer dispersant. Further, as the blending ratio, the weight blending ratio of the polypropylene glycol ethylene oxide adduct and the polymer dispersant is 1: 1 to 10. : 1 is preferable. More preferably, the ratio is 2: 1 to 8: 1. More preferably, the ratio is 3: 1 to 5: 1.

  By containing a certain amount of polymer-based dispersant, the agglomeration speed can be adjusted, the wax particles can be dispersed in the core particles in a coagulated state and can be relaxed, and the wax particles are dispersed in the core particles. It seems to be a ratio that can exert the effect of being uniformly scattered.

  In the toner or toner production method according to the present invention, the polypropylene glycol ethylene oxide adduct is a nonionic surfactant obtained by adding ethylene oxide to propylene glycol, and is preferably a pluronic type nonionic surfactant.

  The ethylene oxide in the total molecule of the polypropylene glycol ethylene oxide adduct is preferably 40 wt% or more and 80 wt% or less. Preferably they are 50 wt% or more and 80 wt% or less, More preferably, 70 wt% or more and 80 wt% or less are preferable.

  This is an appropriate range for forming uniformly agglomerated core particles by combining the aggregation speeds of the resin particles and the colorant particles. This is a range where the balance between hydrophobicity and hydrophilicity can be taken.

  The weight average molecular weight of the propylene glycol moiety which is a hydrophobic group is preferably 1750 or more and 3850 or less. Preferably 2250 or more and 3850 or less are preferable. More preferably 2750 or more and 3850 or less.

  Propylene glycol has low water solubility and is soluble in water up to several hundred molecular weights, but not higher molecular weights. This is because, by setting the weight average molecular weight of the propylene glycol portion, which is a hydrophobic group, to 1750 or more, an adsorption site to the colorant particle is secured, and the colorant particle has appropriate hydrophobicity. Moreover, the effect which prevents aggregation of a colorant particle | grain progressing excessively is acquired by making the weight average molecular weight of the propylene glycol part which is a hydrophobic group into 3850 or less.

  Its chemical structural formula is shown in (Chemical Formula 1). This nonionic surfactant has a shape in which a hydrophilic group is located at both ends with a hydrophobic group in between. a, b, and c are integers, and are set as needed to adjust the weight average molecular weight of the propylene glycol moiety and the weight ratio of ethylene oxide in the total molecule of the polypropylene glycol ethylene oxide adduct.

  In the toner or toner manufacturing method according to the present invention, the polymer dispersant is preferably polyvinyl alcohol or alcohol of partially saponified polyvinyl alcohol.

Copolymer resins having a hydrophilic part and a hydrophobic part in the molecule, for example, styrene-acrylic acid copolymer, styrene-acrylic acid-acrylic acid alkyl ester copolymer, styrene-methacrylic acid copolymer Or acrylic acid-based dispersants such as styrene-methacrylic acid-acrylic acid alkyl ester copolymers,
For example, a maleic acid dispersant such as a styrene-maleic acid copolymer, a styrene-maleic acid half ester copolymer, an acrylic ester-maleic acid copolymer, or a styrene-acrylic acid ester-maleic acid copolymer,
For example, sulfonic acid-based dispersants such as acrylic acid ester-styrene sulfonic acid copolymer, styrene-methacryl sulfonic acid copolymer, or acrylic acid ester-allyl sulfonic acid copolymer, or salts thereof can be mentioned. .

  Alternatively, acrylic monomers containing hydroxyl groups include β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, methacryl Acid γ-hydroxypropyl, 3-chloro-2-hydroxypropyl acrylate, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Water-soluble polymers such as esters, N-methylol acrylamide and N-methylol methacrylamide are preferred.

  Alternatively, a water-soluble urethane resin (such as a reaction product of polyethylene glycol, polycaprolactone diol and the like and polyisocyanate) is preferable.

  Alternatively, water-soluble polymers such as vinyl methyl ether, vinyl ethyl ether, and vinyl propyl ether are preferable.

  Or esters of compounds containing vinyl alcohol and a carboxyl group, such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acrylic acid chloride, methacrylic acid chloride and other acids Water-soluble polymers such as chlorides are preferred.

  Alternatively, water-soluble polymers such as homopolymers or copolymers such as those having a nitrogen atom such as vinylpyridine, vinylpyrrolidone, vinylimidazole, ethyleneimine or a heterocyclic ring thereof are preferable.

  Alternatively, polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxy Polyoxyethylene-based water-soluble polymers such as ethylene stearyl phenyl ester and polyoxyethylene nonyl phenyl ester are preferred.

  Alternatively, water-soluble polymers such as alkyl cellulose, hydroxy-alkyl cellulose, carboxyalkyl cellulose, and celluloses such as methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose are preferable. These celluloses can be dissolved in water at 25 ° C. at 0.5% or more, and those having an etherification degree of 0.6 to 1.5 and an average degree of polymerization of 50 to 3000 are preferable.

Among these, acrylic acid such as styrene-acrylic acid copolymer, styrene-acrylic acid-acrylic acid alkyl ester copolymer, styrene-methacrylic acid copolymer, or styrene-methacrylic acid-alkyl acrylate copolymer. Dispersants,
Maleic acid-based dispersants such as styrene-maleic acid copolymer, styrene-maleic acid half ester copolymer, acrylic acid ester-maleic acid copolymer or styrene-acrylic acid ester-maleic acid copolymer,
A sulfonic acid dispersant such as an acrylate-styrene sulfonic acid copolymer, a styrene-methacryl sulfonic acid copolymer, or an acrylate-allyl sulfonic acid copolymer, or a salt thereof is preferable.

  More preferably, a maleic acid-based dispersant or an acrylic acid-based dispersant is a styrene-acrylic acid copolymer, a styrene-maleic acid copolymer, a styrene-maleic acid half ester copolymer, or an acrylic acid ester-maleic acid copolymer. Polymers or their salts are particularly preferred.

  It is preferable to dissolve the polymer dispersant by forming a salt at the maleic acid or acrylic acid moiety in the polymer dispersant. Examples of the alkali neutralizer include aminomethylpropanol, 2-aminoisopropanol, triethanolamine, and aqueous ammonia.

  Or inorganic alkali agents, such as alkali metal hydroxides, such as sodium hydroxide, lithium hydroxide, or potassium hydroxide, etc. can be mentioned.

  The content of the alkali neutralizer can be an amount (neutralization equivalent) or more that can neutralize the polymer dispersant as a counter ion, and is approximately 1.2 to 1.5 of the neutralization equivalent. It is preferable from the point of cohesion etc. to contain in double quantity.

  In addition, as a polymer dispersant used for wax particles, a polyolefin maleate sodium (Na) salt using a polyolefin such as polyethylene or polypropylene can be preferably used as one having an effect of enhancing the adsorptivity to wax.

  From the viewpoints of the dispersion state of the dispersion, the aggregation property with respect to the aggregation reaction temperature of the core particles, the developability, and the fixability, the polymer-based dispersant has a glass transition point of 40 to 150 ° C., a softening point of 90 to 220 ° C., and a weight average molecular weight of 3000-50,000 and an acid value of 50-250 mgKOH / g are preferable.

  More preferably, the glass transition point is 50 to 130 ° C., the softening point is 100 to 180 ° C., the weight average molecular weight is 3000 to 30,000, the acid value is 80 to 200 mgKOH / g, and more preferably, the glass transition point is 80 to 120. The softening point is preferably 120 to 180 ° C., the weight average molecular weight is 7,000 to 30,000, and the acid value is preferably 100 to 200 mgKOH / g.

  When the glass transition point is lower than 40 ° C., the agglomeration reaction is accelerated and the produced core particles tend to be coarse. When the glass transition point is higher than 150 ° C., the aggregation reaction is delayed, and the wax particles remaining in the aqueous system that do not participate in aggregation tend to increase. When the softening point is lower than 90 ° C., the agglomeration reaction is accelerated and the produced core particles tend to be coarse. When the softening point is higher than 220 ° C., the aggregation reaction is delayed, and the wax particles remaining in the aqueous system that do not participate in aggregation tend to increase. When the weight average molecular weight is less than 3000, the aggregation reaction is accelerated, and the produced core particles tend to be coarse. When the weight average molecular weight is larger than 50,000, the aggregation reaction is delayed, and the wax particles remaining in the aqueous system that do not participate in aggregation tend to increase. When the acid value is less than 50 mgKOH / g, the dispersion stability of the wax dispersion tends to be lowered. When the acid value is larger than 250 mgKOH / g, the progress of aggregation is accelerated and the produced core particles tend to be coarse.

  In particular, the glass transition point of the polymer dispersant is preferably equal to or higher than the temperature at which the core particles are aggregated. Desirably, the glass transition point is 90 ° C. or higher. The reason for this is that in the process of increasing the temperature in the aqueous system, the wax particles tend to aggregate from the temperature range exceeding the glass transition point of the polymer dispersant, which tends to be a large residue floating in the aqueous system. There is a tendency. When the glass transition point of the polymer dispersant is equal to or higher than the aggregation temperature of the core particles, a large residue floating in the aqueous system tends not to be generated.

  The acid value refers to the number of milligrams of potassium hydroxide required to neutralize the acid contained in 1 g of a sample. The sample is dissolved in alcohol-ether and titrated with 0.5N potassium hydroxide using phenolphthalein as an indicator. Performed in accordance with JIS-K-0070.

  Further, in the toner or the toner production method of the present invention, when carbon black is used as a colorant in the black toner, the carbon black preferably contains carbon black having a DBP oil absorption of 45 to 70 (ml / 100 g). . Preferably it is 45-63 (ml / 100g), More preferably, it is 45-60 (ml / 100g), More preferably, it is 45-53 (ml / 100g). Carbon black having a DBP oil absorption of less than 45 (ml / 100 g) has not produced a suitable sample.

  By using carbon black having a DBP oil absorption of 45 to 70 (ml / 100 g), the aggregation of carbon black tends to be relieved to occur abnormally and the carbon black particles tend to be easily incorporated into the core particles. . Moreover, when it is set as the shell structure which made the shell resin particle adhere to the core particle mentioned later, it exists in the tendency for the BET specific surface area value by nitrogen adsorption | suction of a production | generation particle to become small. As a result, fog that is toner adhesion to the non-image area during development tends to be reduced. It is considered that the dispersion state of carbon black affects the surface state.

  Carbon black has characteristics close to inorganic, compared to other organic pigments such as phthalocyanine, quinacridone, and azo, and its aggregating properties (particles when aggregating agent is added) in agglomeration reaction with wax particles and resin particles. Tend to be different. Therefore, it seems preferable to use carbon black having a certain oil absorption characteristic in carbon black.

  In addition, the effect tends to be more exhibited when used with a wax having a certain melting point. When the agglomeration reaction proceeds, the wax is in a molten state, and the carbon black particles are in a powder state. The carbon black particles having a certain DBP oil absorption characteristic absorb oil (adsorb) the melted wax due to its oil absorption. Therefore, there may be a case where the original low-temperature fixability and offset-resistant fixability functions of the wax are inhibited.

  Therefore, by regulating the DBP oil absorption characteristics of carbon black particles in the agglomeration reaction between molten wax having a certain melting point and carbon black particles in a powder state, the phenomenon that carbon black particles first grow is suppressed. Even if the core particles are reduced in size, the carbon black particles are taken into the core particles, and the effect of eliminating the carbon black particles remaining in the core particle dispersion without being aggregated can be obtained. Further, the present inventors have found an effect capable of suppressing the phenomenon that the fixing function of the wax is lowered.

  In the toner or toner production method of the present invention, the surfactant used in the resin particle dispersion is preferably a mixture of a nonionic surfactant and an ionic surfactant. Of the surfactants used in the resin particle dispersion, the nonionic surfactant preferably has 50 to 95 wt% with respect to the total surfactant. More preferably, it is 55-90 wt%, More preferably, it is 60-85 wt%.

  Further, in the toner or the toner production method of the present invention, the resin particles are obtained by emulsion polymerization of a monomer using a polymerization initiator in an aqueous medium, and the addition amount of the polymerization initiator is 0.5 to 2.5 parts by weight with respect to 100 parts by weight of the monomer, the polymerization initiator is a persulfate having a solubility of 4 g or more in 100 g of water at a water temperature of 20 ° C., and the monomer is a styrene monomer And (meth) acrylic acid ester monomer and vinyl monomer having an acid group, the compounding amount of the vinyl compound having an acid group is 0.1 to 5.0 wt% in the monomer It is preferable to do.

  The addition amount of the polymerization initiator tends to affect the aggregation of the resin particles, the colorant particles and the wax particles depending on the amount of the hydrophilic group derived from the polymerization initiator. In other words, by setting the addition amount of the polymerization initiator within the above-described appropriate range, the resin particles are rapidly aggregated, and the resin particles are aggregated with each other without forming the core particles aggregated with the wax particles and the colorant particles. The phenomenon that the coarse particles are generated can be alleviated, and agglomeration of the core particles is prevented from being delayed, leading to improvement in productivity. This is an appropriate range in which the aggregating reaction can be prevented from progressing slowly or conversely. The appropriate amount of the polymerization initiator added is preferably 0.7 to 2.0 parts by weight, more preferably 1.0 to 1.5 parts by weight.

  The polymerization initiator is preferably a persulfate having a solubility of 4 g or more in 100 g of water having a water temperature of 20 ° C. The cohesiveness and fixability of the core particles can be made appropriate by optimizing the amount of hydrophilic groups derived from the polymerization initiator. When the solubility is less than 4 g, it takes time to dissolve the persulfates during the emulsion polymerization reaction, and the productivity becomes slow. The dispersion state of persulfates during emulsification tends to change, and the cohesiveness during the coagulation reaction tends to become unstable.

  It is preferable that the compounding quantity of the vinyl compound which has an acid group is 0.1 to 5.0 weight% in a monomer. Preferably it is 0.2 to 4.5 weight%, More preferably, it is 0.5 to 2.0 weight%. This is a range in which the resin particles, the colorant particles and the wax particles can be properly aggregated.

  The toner production method according to the present invention includes a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed in an aqueous medium. Are mixed to produce a mixed solution, and a flocculant is added to the mixed solution to produce core particles in which resin particles, colorant particles and wax particles are aggregated. The dispersant used in the colorant particle dispersion in which the colorant particles are dispersed includes a polypropylene glycol ethylene oxide adduct.

  In the toner production method of the present invention, the pH of the mixed dispersion obtained by mixing the resin particle dispersion, the colorant particle dispersion, and the wax particle dispersion in an aqueous medium is adjusted to a range of 9.5 to 12.2. It is preferable to do. The pH is preferably adjusted to 10 to 11.5, and more preferably adjusted to the range of 10.5 to 11. The pH can be adjusted by adding 1N NaOH.

  By setting the pH value to 9.5 or more, generation of wax particles and colorant particles that are released without being aggregated can be suppressed, and core particles having a small particle size and a narrow particle size distribution can be formed. By setting the pH value to 12.2 or less, it is possible to form a core particle having a small particle size in which each particle is uniformly dispersed without being coarsened.

  Thereafter, a water-soluble inorganic salt is added to the mixed dispersion, and heat treatment is performed at a temperature equal to or higher than the glass transition temperature (Tg) of the resin particles and / or the melting point of the wax, whereby at least resin particles, colorant particles, and wax particles are obtained. , Core particles having a predetermined volume average particle diameter in which at least a part is melted and aggregated are formed.

  It is preferable that the pH of the liquid when the core particles having the predetermined volume average particle diameter are formed is maintained in the range of 7.0 to 9.5, thereby reducing the liberation of the colorant particles and the wax particles, There is an effect that core particles in which each particle is uniformly dispersed can be obtained.

  The amount of NaOH to be added, the type and amount of flocculant, the pH of the emulsion polymerization resin dispersion, the pH of the colorant dispersion, the pH of the wax dispersion, the heating temperature, and the time are appropriately selected. If the pH of the liquid when the particles are formed is less than 7.0, the colorant or wax released due to poor aggregation increases, and as a result of the time required for aggregation, the core particles produced tend to increase. When the pH exceeds 9.5, the core particles tend to become coarse. In addition, secondary aggregation between core particles tends to occur.

  In addition, when using a persulfate such as potassium persulfate as a polymerization initiator when polymerizing and producing an emulsion polymerization resin, the residue of the resin particle dispersion is decomposed by the heat during the heat aggregation process to change the pH. (Lower), after emulsion polymerization, heating at a certain temperature or higher (preferably 80 ° C. or higher in order to sufficiently disperse the residue) and heating for a certain time (preferably about 1 to 5 hours) It is preferable to perform the treatment. The pH of the resin particle dispersion is preferably 4 or less, more preferably 1.8 or less.

  For the measurement of pH (hydrogen ion concentration), 10 ml of a sample to be measured is collected from the liquid tank using a pipette and placed in a beaker having the same volume. This beaker is immersed in cold water, and the sample is cooled to room temperature (30 ° C. or lower). Using a pH meter (Seven Multi: manufactured by METTLER TOLEDO), immerse the measurement probe in the sample cooled to room temperature. When the meter display is stable, read the value and use it as the pH value.

  The heating rate of the mixed dispersion is preferably from 0.1 to 10 ° C./min. When it is slower than 0.1 ° C./min, the productivity is lowered. If it is faster than 10 ° C./min, the shape tends to be too spherical before the particle surface becomes smooth.

  In the toner production method of the present invention, as a preferred embodiment of core particle generation, a resin particle dispersion, a colorant particle dispersion, and a wax particle dispersion are mixed in an aqueous medium to form a mixed dispersion. A method of heating the mixed dispersion and adding a water-soluble inorganic salt as a flocculant to the mixed dispersion after the liquid temperature of the mixed dispersion reaches a certain temperature is also preferable.

  By adding the flocculant when the temperature of the mixed dispersion reaches a certain level or more, the phenomenon that the agglomeration proceeds slowly with the temperature rise time is avoided, and the agglomeration reaction proceeds at once with the addition of the flocculant, and in a short time. Core particles can be generated. Further, it is possible to form a core particle having a small particle size and a narrow particle size distribution in which each particle is uniformly dispersed.

  Further, as described later, when waxes having different melting points are used in combination, the low melting point wax is first melted in the process of raising the temperature. Since melting starts and aggregation starts, this is an effective method for preventing the formation of aggregates of low melting point wax particles or high melting point particle waxes. It is possible to prevent the wax from being unevenly distributed in the core particles, thereby preventing the particle size distribution of the core particles from being widened and the particle shape from becoming uneven.

  As the flocculant to be added, an aqueous solution containing a water-soluble inorganic salt having a constant water concentration is used. After adjusting the pH value of the aqueous solution, at least a resin particle dispersion, a colorant particle dispersion, and a wax particle dispersion It is also preferable to take a configuration in which the mixture is added to the mixed dispersion.

  It is considered that the aggregating action of the particles as the aggregating agent can be further enhanced by adjusting the pH value of the aqueous solution containing the aggregating agent to a constant value. It is preferable to have a certain relationship with the pH value of the mixed dispersion, and adding an aqueous flocculant solution with a different pH value to the mixed dispersion suddenly disturbs the pH balance of the liquid, so the aggregated particles are coarse. Or wax dispersion tends to be non-uniform. In order to suppress such a phenomenon, it is effective to adjust the pH of the flocculant aqueous solution.

  When the mixed dispersion obtained by mixing the resin particle dispersion, the colorant particle dispersion, and the wax particle dispersion is heat-treated and the pH value of the mixed dispersion before the addition of the aqueous solution containing the flocculant is HG, the flocculant is contained. The pH value of the aqueous solution is preferably adjusted to be in the range of HG + 2 to HG-4. The range is preferably HG + 2 to HG-3, more preferably HG + 1.5 to HG-2, and still more preferably HG + 1 to HG-2.

  When an aqueous flocculant solution having a different pH value is added to the mixed dispersion, the pH balance of the liquid is abruptly disturbed, so that the agglomeration reaction is difficult to proceed with delay, and the core particles tend to become coarse. In order to suppress such a phenomenon, it is effective to adjust the pH of the flocculant aqueous solution. Although the cause is unknown, a configuration in which the pH value of the aqueous solution containing the flocculant is lower than the pH value of the mixed dispersion is more preferable.

  By setting it as HG-4 or more, the aggregating action of the particles as the aggregating agent can be further enhanced, and the agglutination reaction can be accelerated. By setting it to HG + 2 or less, there is an effect of suppressing the phenomenon that the core particle becomes coarse or the particle size distribution becomes broad.

  The timing of adding the flocculant is that the temperature of the mixed dispersion obtained by mixing the resin particle dispersion, the colorant particle dispersion, and the wax particle dispersion reaches or exceeds the melting point of the wax measured by the DSC method described later. A configuration in which a flocculant is added later is preferable. By adding a flocculant in the state where the wax has started to melt, the agglomeration of the wax particles to be melted, the resin particles and the colorant particles proceeds all at once. It seems that melting progresses and particles are formed.

  At this time, when the temperature of the mixed dispersion reaches the specific temperature of the wax, the aggregation of the particles proceeds by adding an aggregating agent, and then 0.5 to 5 hours, preferably 0.5 to 3 hours. Preferably, core particles having a predetermined particle size distribution are produced by heat treatment for 1 to 2 hours. The heat treatment may be performed while keeping the specific temperature of the wax, but it is preferably 80 to 95 ° C, more preferably 90 to 95 ° C. Aggregation reaction can be accelerated, leading to reduction of processing time.

  Furthermore, as described later, when two or more kinds of wax are included, it is preferable to adjust the specific temperature of the wax having the lower melting point. More preferably, the specific temperature of the wax having the higher melting point is adjusted. It is effective to add the flocculant in a temperature state where the melting of the wax particles is started.

  The flocculant may be added all at once, but it is also preferable to add the flocculant dropwise over a period of 1 to 120 minutes. Although it may be divided, continuous dripping is preferred. By dropping the flocculant at a constant rate into the heated mixed dispersion, the flocculant gradually and uniformly mixes with the entire mixed dispersion in the reaction kettle, and the uneven distribution makes the particle size distribution broad. In addition, there is an effect of suppressing the generation of floating particles without adding to the aggregation of wax particles and colorant particles. Moreover, the rapid fall of the liquid temperature of a mixed dispersion liquid can be suppressed. Preferably it is 5-60 min, More preferably, it is 10-40 min, More preferably, it is 15-35 min. For 1 min or longer, the shape of the core particles does not proceed to an indefinite shape, and a stable shape is obtained. By setting it to 120 min or less, an effect of suppressing the presence of particles floating alone without adding to the aggregation of the colorant particles and the wax particles can be obtained.

  A configuration in which 1 to 50 parts by weight of the flocculant is dropped with respect to 100 parts by weight of the total of the resin particles, the colorant particles and the wax particles is preferable. Preferably it is 5-25 weight part, More preferably, it is 5-20 weight part, More preferably, it is 10-15 weight part. When the dripping amount of the flocculant is less than 1 part by weight, the agglomeration reaction does not proceed, and when the dripping amount of the flocculant is too large, the resulting particles tend to be coarse.

  In addition to the resin particle dispersion, the colorant particle dispersion, and the wax particle dispersion, ion-exchanged water may be added to the mixed dispersion in order to adjust the solid concentration in the liquid. The solid concentration in the liquid is preferably 5 to 40 wt%.

  Further, as the flocculant, it is also preferable to use a water-soluble inorganic salt adjusted to a constant concentration with ion exchange water or the like. The concentration of the flocculant aqueous solution is preferably 5 to 50 wt%.

  The toner production method of the present invention may further include a step of further shifting the pH in the core particle dispersion in which the core particles in which the resin particles, the colorant particles, and the wax particles are dispersed are dispersed to 0.5 to 5 acid side. preferable.

  After the core particles having a certain particle diameter are formed, the core particles can be prevented from becoming coarse even if the heat treatment is continued by further adjusting the pH. The surface of the core particle can be made smoother, and the shape can be made close to a spherical shape. Moreover, the effect which accelerates | stimulates adhesion of shell resin in the following process is acquired.

  The pH in the liquid when core particles having a certain particle diameter are formed is in the range of 7.0 to 9.5, and is further shifted 0.5 to 5 to the acidic side. It is preferable to shift to this range.

  Preferably, the pH is shifted 1.5 to 4 to the acidic side and the pH is shifted to 3 to 8, more preferably the pH is shifted to 2 to 3 and the pH is preferably shifted to 4 to 7.5.

  In the toner production method of the present invention, the shell resin particle dispersion in which the shell resin particles are dispersed is added to and mixed with the core particle dispersion in which the core particles are dispersed. A configuration in which toner base particles are produced by fusing the toner particles is also preferable. In this case, the resin particles used for the core particles may be referred to as first resin particles.

  By forming a fused layer of shell resin particles on the surface of the core particle, an effect on stabilization of charging can be obtained (sometimes referred to as a shell layer). In addition, from the viewpoint of improving the storage stability of the toner at a high temperature, resin particles having a high glass transition point (Tg (° C.)) are used. From the viewpoint of charging stability, it is desirable to form resin particles containing a charge adjusting agent as a shell layer.

  As a condition for dropping the shell resin particle dispersion into the core particle dispersion, the dropping rate of the shell resin particles is 0.14 parts by weight / min to 2 parts by weight / min with respect to 100 parts by weight of the generated core particles. The structure which produces | generates by dripping on dripping conditions is preferable. Preferably it is 0.15 weight part / min-1 weight part / min, More preferably, it is 0.2 weight part / min-0.8 weight part / min.

  The addition time of the shell resin particle dispersion is added as it is when the core particles reach a predetermined particle size. The addition is preferably carried out by dropping a constant amount quantitatively continuously. When a predetermined total amount is added all at once, or when the dropping rate of the shell resin particles exceeds 2 parts by weight / min, only the shell resin particles tend to aggregate and the particle size distribution tends to be broad. In addition, when the input amount is increased, the liquid temperature rapidly decreases and the agglomeration reaction stops, and some of the shell resin particles remain floating in the aqueous system without being attached to the core particles. May end up.

  Further, when the dropping rate of the shell resin particles is less than 0.14 parts by weight / min, the amount of the shell resin particles attached to the core particles per unit time is reduced, and the core particles are separated when the heating is continued. As a result, the core particles become coarse and the particle size distribution tends to be broad.

  By optimizing the dropping conditions of the shell resin particle dispersion, aggregation of the core particles or aggregation of only the shell resin particles can be prevented, thereby enabling generation of particles having a small particle size and a narrow particle size distribution.

  A configuration in which the shell resin particle dispersion is dropped is preferable so that the fluctuation of the liquid temperature of the core particle dispersion in which the produced core particles are dispersed is suppressed to within 10%.

  In the configuration in which the shell resin particles are fused to the core particles, the shell resin particle dispersion in which the shell resin particles are dispersed is added to the core particle dispersion, and heat treatment is performed on the core particles, and the shell resin particles are converted into the core particles. As a condition for forming the resin fusion layer to be fused, it is preferable to add after adjusting the pH value of the shell resin particle dispersion to a certain range.

  By adjusting the pH value of the shell resin particle dispersion to a certain range and adding the shell resin particle dispersion, the generation of floating shell resin particles that do not participate in fusion is suppressed, and the shell resin particles adhere to the core particles. The objective is to make the particle size favorable, or to suppress the occurrence of secondary aggregation between the core particles.

  In the configuration in which the pH value of the shell resin particle dispersion is adjusted to a certain range, the pH value of the shell resin particle dispersion adjusted to an alkaline state is preferably in the range of 7.5 to 10.5. Preferably it is 8.5-10, More preferably, it is 9-9.5. By adjusting the shell resin particle dispersion to the alkali state described above, the generation of white particles in which the shell resins are aggregated and the generation of secondary particles in which the core particles are aggregated are suppressed, and the shell resin is adhered to the core particles. The effect which promotes is acquired.

  Moreover, it is preferable to add the shell resin particle dispersion liquid in which the shell resin particles whose pH value is adjusted to an alkaline state are dispersed to the core particle dispersion liquid having a pH value in the range of 7 or less and 2 or more. By adjusting the pH value of the core particle dispersion to the above-described range, the adhesion of the shell resin particles to the core particles is promoted, the generation of floating shell resin particles that do not participate in fusion is suppressed, It is possible to suppress the occurrence of aggregation and form a narrow particle size distribution with a small particle size. Moreover, when the pH value of the core particle dispersion is set to 7 or less to be in an acidic state, for example, when magnesium sulfate is used as the flocculant, an effect of removing remaining magnesium hydroxide can be obtained. If magnesium hydroxide remains, the toner tends to absorb moisture when left under high humidity, so it is also aimed to suppress absorption.

  Furthermore, by causing the pH value of the shell resin particle dispersion and the pH value of the core particle dispersion to have a certain relationship, the pH balance in the aqueous system is partly disturbed, so that the shell resin particles to the core particles The aim is to promote the adhesion of the particles, suppress the generation of floating shell resin particles that do not participate in fusion, and further suppress the occurrence of secondary aggregation between the core particles.

  The pH value of the core particle dispersion is in the range of 7 or less and 2 or more, and the shell resin particle dispersion is added after adjusting the pH value of the shell resin particle dispersion to 7.5 to 10.5. Adhesion is promoted, generation of floating shell resin particles that do not participate in fusion is suppressed, generation of secondary aggregation between core particles is suppressed, and a narrow particle size distribution can be formed with a small particle size.

  When the pH value of the core particle dispersion is less than 2 and the pH value of the shell resin particle dispersion is less than 7.5, the adhesion of the shell resin particles to the core particles does not proceed, and the shell resin particles are transferred to the core particles. There is a tendency to remain floating without being fused. When the pH value of the core particle dispersion is greater than 7 and the pH value of the shell resin particle dispersion is greater than 10.5, the adhesion of the shell resin particles to the core particles does not proceed, and the produced particles It tends to be coarse. The pH value can be adjusted by adding sodium hydroxide or hydrochloric acid solution.

  It is preferable to maintain the pH value of the shell resin particle dispersion and the core particle dispersion in a certain relationship, and the pH value of the shell resin particle dispersion in which the shell resin particles are dispersed is the core particle dispersion in which the core particles are dispersed. It is preferable to adjust the pH to a value higher than the pH value, that is, to be added in an alkaline state.

  The pH value of the shell resin particle dispersion in which the shell resin particles are dispersed is preferably 0.5 or more higher than the pH value of the core particle dispersion in which the core particles are dispersed. More preferably, it is 1 or more, More preferably, it is 2 or more, Preferably it is 5 or less. When the difference in pH value is smaller than 0.5, the generation of floating shell resin particles that do not participate in fusion tends to increase. On the other hand, when the difference in pH value exceeds 5, floating shell resin particles that do not participate in fusion are generated, and secondary agglomeration between core particles occurs, and the generated particles tend to be coarse.

  When the pH value of the shell resin particle dispersion in which the shell resin particles are dispersed is lower than the pH value of the core particle dispersion in which the core particles are dispersed, the generation of shell resin particles tends to increase, It remains cloudy.

  Further, after the shell resin particles are adhered to the surface of the core particles, the pH in the aqueous system is further adjusted to a range of 3.2 to 6.8, and then the temperature is 0.5 or more at a temperature equal to or higher than the glass transition temperature of the shell resin particles. It is also preferable to employ a method of heat treatment for ˜5 hours. By setting the pH within this range, it is possible to further promote the surface smoothness of the particle shape while suppressing secondary aggregation between the core particles. In addition, in a system using magnesium sulfate, which is a water-soluble inorganic salt added as a flocculant, magnesium hydroxide produced by agglomeration reaction that is partially alkaline is oxidized in an acid state and removed as water-soluble. Thus, the effect of lowering moisture absorption, which is a phenomenon in which the toner easily absorbs water, can be obtained.

  In order to improve the durability, storage stability, and high temperature non-offset property of the toner, the thickness of the resin layer fused with the shell resin particles is preferably 0.5 μm to 2 μm. If the thickness of the resin layer is less than 0.5 μm, the effects of storage stability and high temperature non-offset properties cannot be exhibited, and if the thickness of the resin layer is more than 2 μm, the low-temperature fixability is inhibited.

  It is preferable that the main component of the surfactant used in the shell resin particle dispersion is a nonionic surfactant, and the surfactant used in the shell resin particle dispersion is a nonionic surfactant and an ionic surfactant. A configuration in which the nonionic surfactant has 50 to 95 wt% with respect to the entire surfactant is preferable. More preferably, it is 55-90 wt%, More preferably, it is preferable to have 60-85 wt%. By setting it to 50 wt% or more, adhesion of the shell resin particle fine particles to the core particles can be promoted. By setting it to 95 wt% or less, there is an effect of stabilizing the dispersion of the resin particles themselves in the resin particle dispersion.

  A glass-lined SUS kettle as a preferred reaction kettle used for the agglomeration reaction is not particularly limited as an agitating blade for agitating the dispersion, but a blade shape having a wide width in the depth direction (flat blade) is used. It is valid. As the flat plate wing, a trade name Max Blend wing manufactured by Sumitomo Heavy Industries, Ltd. or a full zone wing manufactured by Shinko Pantech Co., Ltd. is effective.

  FIG. 7 is a schematic diagram showing the configuration of the Max Blend wing, and FIG. 8 is a plan view seen from above. Moreover, the structure of a full zone blade | wing is shown in the schematic in FIG. 9, and the top view seen from the top in FIG. A shaft 301 is connected to a stirring motor (not shown). 302 is a stirring tank, 303 is a water surface of the liquid, 304 is a flat max blend blade, and 305 holes are provided in the blade to adjust the stirring strength of the liquid. Reference numeral 306 denotes a flat rectangular blade, and a stirring blade 307 is provided below the flat rectangular blade. The tip is bent about 130 degrees. Reference numeral 308 denotes the length of the stirring blade.

  The rotational speed of the stirring blade varies depending on the particle concentration in the dispersion and the target particle size, but is preferably 0.5 to 2.0 m / s. More preferably, it is 0.7-1.8 m / s, More preferably, it is 1.0-1.6 m / s. When the rotation speed of the stirring blade is too low than 0.5 m / s, the particle size of the generated particles tends to be large and the particle size distribution tends to be widened. If the rotational speed of the stirring blade is higher than 2.0 m / s, the aggregation of particles is hindered, the shape is likely to be indefinite, and the generation of particles is difficult.

  After the particles are formed in the aqueous system, toner base particles can be obtained through an arbitrary washing step, solid-liquid separation step, and drying step. In this washing step, washing with ion-exchanged water is preferably performed from the viewpoint of improving the chargeability. A method of washing using an acid and an alkali is also preferable.

  There is no restriction | limiting in particular as a separation method in a solid-liquid separation process, From a viewpoint of productivity, well-known filtration methods, such as a suction filtration method and a pressure filtration method, are mentioned preferably.

  There is no restriction | limiting in particular as a drying method in a drying process, Well-known drying methods, such as a flash jet drying method, a fluidized drying method, and a vibration type fluidized drying method, are mentioned preferably from a viewpoint of productivity.

  As the flocculant, a water-soluble inorganic salt is selected, and examples thereof include alkali metal salts and alkaline earth metal salts. Examples of the alkali metal include lithium, potassium, and sodium, and examples of the alkaline earth metal include magnesium, calcium, strontium, and barium. Of these, potassium, sodium, magnesium, calcium, and barium are preferable. Examples of the counter ion (anion constituting the salt) of the alkali metal or alkaline earth metal include chloride ion, bromide ion, iodide ion, carbonate ion and sulfate ion. It is also preferable to use it after adjusting to a constant concentration with ion-exchanged water or the like.

  Examples of the aqueous medium include water such as distilled water and ion exchange water, and alcohols. These may be used individually by 1 type and may use 2 or more types together. The content of the polar surfactant in the dispersant having the polarity cannot be generally defined and can be appropriately selected according to the purpose.

  Examples of nonionic surfactants include higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, fatty acid amide ethylene oxide adducts, and fats and ethylene oxides. Adduct, Polyethylene glycol type nonionic surfactant such as polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl of other alcohol And polyhydric alcohol type nonionic surfactants such as ethers and fatty acid amides of alkanolamines.

  Examples of the ionic surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap, and cationic surfactants such as an amine salt and a quaternary ammonium salt. Etc.

  Specific examples of the anionic surfactant include sodium dodecylbenzenesulfonate, sodium dodecylsulfate, sodium alkylnaphthalenesulfonate, sodium dialkylsulfosuccinate and the like.

Specific examples of the cationic surfactant include alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, distearyl ammonium chloride and the like. These may be used individually by 1 type and may use 2 or more types together.
(2) Wax In oilless fixing without using oil in the fixing roller, low temperature fixing, high temperature non-offset property, or improvement of separation from a heating roller such as copy paper during fixing, further low temperature fixing, high temperature resistance In order to increase the margin of fixing characteristics that conflict with each other in terms of offset property and storage stability at high temperatures, and to improve the functionality thereof, it is preferable to add a wax, and it is preferable to add a plurality of waxes.

  In the toner or the toner manufacturing method of the present invention, the wax is configured to include at least a wax having an endothermic peak temperature of 50 to 90 ° C. In order to achieve low-temperature fixing, it is preferable to use a wax having a low melting point. Preferably it is 55-85 degreeC, More preferably, it is 58-85 degreeC, More preferably, it is 68-74 degreeC. Storage stability is improved by setting it to 50 ° C. or higher, and low-temperature fixability and color glossiness are improved by setting it to 90 ° C. or lower.

  In the toner or toner production method of the present invention, as a preferred embodiment of the wax, a configuration in which a plurality of waxes are added is also preferred.

  As a preferred first wax form, the wax contains at least the first wax and the second wax, and the endothermic peak temperature (referred to as the melting point Tmw1 (° C.)) of the first wax is 50 to 90 ° C. The endothermic peak temperature (melting point Tmw2 (° C.)) of the second wax by DSC method is preferably 80 to 120 ° C. Tmw1 is preferably 55 to 85 ° C, more preferably 58 to 85 ° C, and still more preferably 68 to 74 ° C. Tmw2 is more preferably 85 to 100 ° C, further preferably 90 to 100 ° C.

  By using waxes having different melting points, the functions of the wax are separated, so that both low temperature fixing and high temperature offset resistance can be achieved, and a wide fixing temperature range characteristic can be obtained.

  In addition, when the core particles are generated by the wax particle dispersant using the specific dispersant described above, the aggregation progresses uniformly, and the wax particles and the colorant particles that float without being added to the aggregate are reduced. It is effective for producing core particles having a narrow particle size distribution.

  When the melting point Tmw1 (° C.) is lower than 50 ° C., the core particles to be produced tend to be coarse and the storage stability tends to deteriorate. When it is higher than 90 ° C., the low-temperature fixability and the color gloss tend not to be improved.

  When the melting point Tmw2 (° C.) is smaller than 80 ° C., the high temperature non-offset property and the paper separation property tend to be weakened. When the temperature exceeds 120 ° C., the cohesiveness of the wax decreases, the number of free particles that do not aggregate in the aqueous system increases, and the shape tends to be uneven.

  In the form using a plurality of waxes, as a preferred second form, the wax contains at least a first wax and a second wax, and the first wax is a higher alcohol and carbon having 16 to 24 carbon atoms. It is preferable that the ester wax which consists of at least one of the higher fatty acids of several 16-24 is included, and the second wax contains an aliphatic hydrocarbon wax.

  Moreover, in the form using a plurality of waxes, as a preferred third form, the wax contains at least a first wax and a second wax, and the first wax has an iodine value of 25 or less and a saponification value of 30 to 30. It is preferable that the wax contains 300 and the second wax contains an aliphatic hydrocarbon wax.

  In the second and third preferred forms of the wax, the endothermic peak temperature (melting point Tmw1 (° C.)) of the first wax by DSC is 50 to 90 ° C., preferably 55 to 85 ° C., more preferably 58 to It is 85 degreeC, More preferably, it is 68-74 degreeC.

  When the temperature is lower than 50 ° C., the storage stability and heat resistance of the toner tend to deteriorate. When the temperature exceeds 90 ° C., the cohesiveness of the wax decreases, the number of free particles that do not participate in the coagulation in the aqueous system increases, and the low-temperature fixability and glossiness tend not to improve.

  Further, the endothermic peak temperature (melting point Tmw2 (° C.)) of the second wax by DSC method is 80 to 120 ° C., preferably 85 to 100 ° C., more preferably 90 to 100 ° C. When the temperature is lower than 80 ° C., the storage stability is deteriorated, the high temperature non-offset property and the separation property of the copy paper from the fixing roller tend to be weakened. When the temperature exceeds 120 ° C., the cohesiveness of the wax decreases, and the free particles that do not participate in the coagulation increase in the aqueous system, and the low-temperature fixability and color translucency tend to be inhibited.

  In the second or third form preferable as a wax, a fat containing a first wax containing a specific wax together with a second wax containing a specific aliphatic hydrocarbon wax is used as the wax. Group hydrocarbon wax suppresses the presence of particles that are not agglomerated in the core particles, suppresses the particle size distribution of the core particles from broadening, and the core particles rapidly become coarse when shelled. Can be suppressed.

  During the heat agglomeration, the first wax becomes more compatible with the resin, which promotes the agglomeration of the aliphatic hydrocarbon wax with the resin. It seems that it can be prevented. Furthermore, the first wax tends to be improved in low-temperature fixability due to partial progress of compatibilization with the resin. In addition, since the aliphatic hydrocarbon wax hardly compatibilizes with the resin, this wax can exhibit the function of improving the high temperature offset property and the separation property of the copy paper from the fixing roller. That is, the first wax has a function as a dispersion aid during the emulsification dispersion treatment of the aliphatic hydrocarbon wax, and further has a function as a low-temperature fixing aid.

  In the first, second or third preferred form of the wax, when the core particles are formed by aggregating the wax particles having different melting points with the resin particles and the colorant particles in the aqueous system, the first wax, the second When the dispersion obtained by separately emulsifying and dispersing each of the waxes is mixed with the resin dispersion and the colorant dispersion and heated to agglomerate, the wax floats without being taken into the core particles due to the difference in the melting rate of the wax. Presence of particles and aggregation of core particles tend not to proceed, and the particle size distribution tends to spread.

  Therefore, in the production of the wax particle dispersion, it is preferable that the first wax and the second wax are mixed and emulsified and dispersed. In this method, the first wax and the second wax are heated and emulsified and dispersed in the emulsifying and dispersing apparatus at a constant blending ratio. The charging may be performed separately or simultaneously, but it is preferable that the final dispersion liquid contains the first wax and the second wax in a mixed state.

  Further, in the first, second or third preferred form as the wax, when the weight ratio of the first wax to 100 parts by weight of the wax in the dispersion of wax particles is ES1, and the weight ratio of the second wax is FT2, FT2 / ES1 is preferably 0.2 to 10. More preferably, it is 1-9, More preferably, it is the range of 1.5-3. If FT2 / ES1 is smaller than 0.2, that is, if the first wax weight ratio is too large, the effect of high temperature non-offset property cannot be obtained, and the storage stability tends to deteriorate. On the other hand, if FT2 / ES1 is larger than 10, that is, if the second wax weight ratio is too large, low-temperature fixing cannot be realized, and the above-described core particles tend to be coarse. Further, setting the blending ratio of FT2 to 1.5 times or more and 3 times or less of ES1 is a well-balanced ratio capable of satisfying both low temperature fixing property, high temperature storage stability and fixing high temperature non-offset property.

  In the first, second, or third embodiment preferable as the wax, the total amount of added wax is preferably 5 to 30 parts by weight with respect to 100 parts by weight of the binder resin. Preferably it is 8-25 weight part, More preferably, 10-20 weight part is preferable. When the amount is less than 5 parts by weight, the low temperature fixing property, the high temperature non-offset property, and the separation property of the copying paper from the fixing roller tend to deteriorate. When the amount is more than 30 parts by weight, it tends to be difficult to control particles having a small particle diameter.

  In the first, second, or third embodiment preferable as the wax, a configuration in which Tmw2 is higher than Tmw1 by 5 ° C. or more and 50 ° C. or less is preferable. More preferably, the temperature is 10 ° C. or higher, 40 ° C. or lower, more preferably 15 ° C. or higher, and preferably 35 ° C. or lower. The functions of a plurality of waxes can be efficiently separated, and there is an effect of achieving both low-temperature fixing properties, high-temperature non-offset properties, and paper separation properties. When the temperature is lower than 5 ° C., the effect of achieving both low-temperature fixability, high-temperature non-offset property, and separation property of the copy paper from the fixing roller tends to be difficult to obtain. When the temperature is higher than 50 ° C., the first wax and the second wax are phase-separated and tend not to be uniformly taken into the toner particles.

  A preferred first wax includes at least one ester composed of at least one of a higher alcohol having 16 to 24 carbon atoms and a higher fatty acid having 16 to 24 carbon atoms. By using this wax, it is possible to suppress the presence of particles that are not incorporated into the core particles and the aliphatic hydrocarbon wax to float, to suppress the particle size distribution of the core particles from being broadened, and to form a shell. In addition, it is possible to alleviate the phenomenon that the core particles are coarsened rapidly. Moreover, low temperature fixing can be promoted. The combined use with the second wax improves the high temperature non-offset property and separability of the copy paper from the fixing roller and prevents coarsening of the particle size, and enables generation of core particles having a small particle size and a narrow particle size distribution.

  As alcohol components, in addition to monoalcohols such as methyl, ethyl, propyl or butyl, glycols such as ethylene glycol or propylene glycol or multimers thereof, triols such as glycerin or multimers thereof, and polyhydric alcohols such as pentaerythritol Sorbitan or cholesterol is preferred. When the alcohol component is a polyhydric alcohol, the higher fatty acid may be a mono-substituted product or a poly-substituted product.

Specifically, esters comprising a higher alcohol having 16 to 24 carbon atoms and a higher fatty acid having 16 to 24 carbon atoms, such as stearyl stearate, palmityl palmitate, behenyl behenate or stearyl montanate,
Esters comprising a higher fatty acid having 16 to 24 carbon atoms such as butyl stearate, isobutyl behenate, propyl montanate or 2-ethylhexyl oleate and a lower monoalcohol,
Montanic acid monoethylene glycol ester, ethylene glycol distearate, monostearic acid glyceride, monobehenic acid glyceride, tripalmitic acid glyceride, pentaerythritol monobehenate, pentaerythritol dilinoleate, pentaerythritol trioleate or pentaerythritol tetrastearate, etc. Esters comprising a higher fatty acid having 16 to 24 carbon atoms and a polyhydric alcohol, or
Higher fatty acids having 16 to 24 carbon atoms and polyhydric alcohols such as diethylene glycol monobehenate, diethylene glycol dibehenate, dipropylene glycol monostearate, distearic diglyceride, tetrastearic acid triglyceride, hexabehenic acid tetraglyceride or decastearic acid decaglyceride Preferable examples include esters composed of multimers. These waxes may be used alone or in combination of two or more.

  When the alcohol component and / or the acid component has less than 16 carbon atoms, the function as a dispersion aid is hardly exhibited, and when it exceeds 24, the function as a low-temperature fixing aid is hardly exhibited.

  A preferred first wax includes a wax having an iodine value of 25 or less and a saponification value of 30 to 300. By using together with the second wax, it is possible to prevent the core particles from becoming coarse and to generate core particles having a small particle size and a narrow particle size distribution. By regulating the iodine value, the effect of improving the dispersion stability of the wax can be obtained, the core particles can be formed uniformly with the resin particles and the colorant particles, and the core particles with a small particle size and narrow particle size distribution can be formed. And The iodine value is preferably 20 or less, the saponification value is 30 to 200, more preferably the iodine value is 10 or less, and the saponification value is 30 to 150.

  If the iodine value is larger than 25, the core particles cannot be formed uniformly with the resin particles and the colorant particles, and the floating particles of the wax that do not participate in the aggregation increase, resulting in coarse core particles and broad particle size distribution. It tends to be easy. If the floating particles remain in the toner, filming of the photoreceptor or the like is caused. The repulsion due to the charge effect of the toner is difficult to be mitigated during the multi-layer transfer of toner in the primary transfer. When the saponification value is less than 30, it becomes difficult to form a uniform core particle having a small particle diameter, and the chargeability of the toner is lowered, and the chargeability during continuous use tends to be lowered. When the saponification value is larger than 300, suspended matter in the aqueous system increases, and fog and toner scattering tend to increase.

  It is preferable that the heat loss at 220 ° C. of the wax having a defined iodine value and saponification value is 8% by weight or less. If the loss on heating is more than 8% by weight, the glass transition point of the toner is lowered and the storage stability of the toner tends to be impaired. Further, it adversely affects the development characteristics, and tends to cause fogging and photoconductor filming. The particle size distribution of the generated toner tends to be broad.

Molecular weight characteristics in gel permeation chromatography (GPC) of waxes with prescribed iodine value and saponification value, number average molecular weight is 100 to 5000, weight average molecular weight is 200 to 10,000, and ratio of weight average molecular weight to number average molecular weight (weight average molecular weight / Number average molecular weight) is 1.01 to 8, the ratio of Z average molecular weight to number average molecular weight (Z average molecular weight / number average molecular weight) is 1.02 to 10, and the molecular weight is 5 × 10 ² to 1 × 10 ⁴ . It preferably has at least one molecular weight maximum peak. More preferably, the number average molecular weight is 500-4500, the weight average molecular weight is 600-9000, the ratio of weight average molecular weight to number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01-7, Z average molecular weight and number average. The molecular weight ratio (Z average molecular weight / number average molecular weight) is 1.02 to 9, more preferably the number average molecular weight is 700 to 4000, the weight average molecular weight is 800 to 8000, and the ratio of the weight average molecular weight to the number average molecular weight (weight average). (Molecular weight / number average molecular weight) is 1.01 to 6, and the ratio of Z average molecular weight to number average molecular weight (Z average molecular weight / number average molecular weight) is 1.02 to 8.

The number average molecular weight is less than 100, the weight average molecular weight is less than 200, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is less than 1.01, and the ratio of the Z average molecular weight to the number average molecular weight When (Z average molecular weight / number average molecular weight) is smaller than 1.02 and the molecular weight maximum peak is located in a range smaller than 5 × 10 ² , the storage stability is deteriorated, and photoconductor filming is likely to occur. Tend to be. The particle size distribution of the generated toner tends to be broad.

The number average molecular weight is greater than 5000, the weight average molecular weight is greater than 10,000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is greater than 8, and the ratio of the Z average molecular weight to the number average molecular weight (Z When the average molecular weight / number average molecular weight) is larger than 10 and the molecular weight maximum peak is located in a range larger than the region of 1 × 10 ⁴ , the low-temperature fixability tends to be lowered. It tends to be difficult to reduce the particle size when the emulsified dispersed particles of wax are produced.

  As the first wax, materials such as a meadow foam oil derivative, carnauba wax derivative, jojoba oil derivative, wood wax, beeswax, ozokerite, carnauba wax, canderia wax, ceresin wax or rice wax are also preferred, and these Derivatives are also preferably used. One type or a combination of two or more types can be used.

  As the meadow foam oil derivative, meadow foam oil fatty acid, metal salt of meadow foam oil fatty acid, meadow foam oil fatty acid ester, hydrogenated meadow foam oil or meadow foam oil triester can be preferably used. An emulsion dispersion having a small particle size and a uniform particle size distribution can be prepared. It is a preferable material that is effective for low-temperature fixability in oilless fixing, prolonging the life of the developer, and improving transferability. These can be used alone or in combination of two or more.

  The meadow foam oil fatty acid obtained by saponification and decomposition of meadow foam oil is preferably composed of a fatty acid having 4 to 30 carbon atoms. As the metal salt, a metal salt such as sodium, potassium, calcium, magnesium, barium, zinc, manganese or aluminum can be used. High temperature non-offset property is good.

  Meadowfoam oil fatty acid esters include, for example, esters such as methyl, ethyl, butyl, glycerin, pentaerythritol, polypropylene glycol, or trimethylolpropane. Ester or meadow foam oil fatty acid trimethylolpropane ester is preferred. Effective for low-temperature fixability.

  Hydrogenated Meadowfoam oil is obtained by hydrogenating Meadowfoam oil to make unsaturated bonds saturated bonds. Low temperature fixability and glossiness can be improved.

  Furthermore, an esterification reaction product of a meadow foam oil fatty acid and a polyhydric alcohol such as glycerin, pentaerythritol, trimethylolpropane, or the like is obtained by using tolylene diisocyanate (TDI), diphenylmethane-4,4′-diisocyanate (MDI), or the like. An isocyanate polymer of a meadow foam oil fatty acid polyhydric alcohol ester obtained by crosslinking with isocyanate can also be preferably used. Effective for extending the life of a two-component developer.

  As jojoba oil derivatives, jojoba oil fatty acid, metal salt of jojoba oil fatty acid, jojoba oil fatty acid ester, hydrogenated jojoba oil, jojoba oil triester, maleic acid derivative of epoxidized jojoba oil, isocyanate of jojoba oil fatty acid polyhydric alcohol ester Polymers and halogenated modified jojoba oil can also be preferably used. An emulsion dispersion having a small particle size and a uniform particle size distribution can be prepared. Easy mixing and dispersion of resin and wax. It is a preferable material that is effective for low-temperature fixability in oilless fixing, prolonging the life of the developer, and improving transferability. These can be used alone or in combination of two or more.

  Jojoba oil fatty acid obtained by saponifying and decomposing jojoba oil consists of fatty acids having 4 to 30 carbon atoms. As the metal salt, a metal salt such as sodium, potassium, calcium, magnesium, barium, zinc or aluminum can be used. High temperature non-offset property is good.

  Examples of jojoba oil fatty acid esters include methyl, ethyl, butyl, glycerin, pentaerythritol, polypropylene glycol, trimethylolpropane and the like, and in particular, jojoba oil fatty acid pentaerythritol monoester, jojoba oil fatty acid pentaerythritol triester, jojoba Oil fatty acid trimethylolpropane ester and the like are preferable. Effective for low-temperature fixability.

  Hydrogenated jojoba oil is obtained by hydrogenating jojoba oil to make unsaturated bonds saturated bonds. Effective for improving low-temperature fixability and gloss.

  Furthermore, esterification reaction products of jojoba oil fatty acid and polyhydric alcohols such as glycerin, pentaerythritol, trimethylolpropane, tolylene diisocyanate (TDI), diphenylmethane-4,4′-disicocyanate (MDI), etc. An isocyanate polymer of jojoba oil fatty acid polyhydric alcohol ester obtained by crosslinking with the above isocyanate can also be preferably used. Effective for extending the life of a two-component developer.

  The saponification value refers to the number of milligrams of potassium hydroxide required to saponify 1 g of a sample. In the case of a wax, the alkali amount necessary for cleaving the ester bond is the saponification value, and a wax having a high saponification value means that the number of ester bonds is large. It is considered that there are many hydrocarbons. To determine the saponification value, a sample is saponified in an alcohol solution of about 0.5 N potassium hydroxide.

  The iodine value refers to the amount of halogen absorbed when halogen is allowed to act on a sample, and expressed in terms of g relative to 100 g of the sample. It is the number of grams of iodine absorbed, and the higher this value, the higher the degree of unsaturation of the fatty acid in the sample. Add iodine and mercury (II) chloride alcohol solution or iodine glacial acetic acid solution to chloroform or carbon tetrachloride solution of the sample, and titrate the remaining iodine without reacting with sodium thiosulfate standard solution to absorb iodine Calculate the amount.

  For the measurement of the loss on heating, the weight of the sample cell is precisely weighed to 0.1 mg (W1 mg), 10 to 15 mg of the sample is put in this, and it is precisely weighed to 0.1 mg (W2 mg). The sample cell is set on a differential thermobalance, and the measurement is started with a weighing sensitivity of 5 mg. After the measurement, the weight loss when the sample temperature reaches 220 ° C. is read to 0.1 mg by the chart (W3 mg). The apparatus is TGD-3000 manufactured by Vacuum Riko, the heating rate is 10 ° C./min, the maximum temperature is 220 ° C., the holding time is 1 min, and the heating loss (%) = W 3 / (W 2 −W 1) × 100. .

  Measurement of endothermic peak temperature (melting point ° C) and onset temperature by DSC of wax uses TA Instruments Q100 type (use a genuine electric refrigerator for cooling), measurement mode is “standard”, purge gas (N2) The flow rate is 50 ml / min, the power is turned on, the temperature in the measurement cell is set to 30 ° C., and the sample is left in that state for 1 hour. The aluminum pan containing the sample was put into the measuring instrument. Thereafter, the temperature was maintained at 5 ° C. for 5 minutes, and the temperature was increased to 150 ° C. at a temperature increase rate of 1 ° C./min. For the analysis, “Universal Analysis Version 4.0” attached to the apparatus was used. In the graph, the horizontal axis represents the bath temperature, the vertical axis represents the heat flow, the temperature at which the endothermic curve starts to rise from the baseline was the onset temperature, and the peak value of the endothermic curve was the endothermic peak temperature (melting point).

  As the second wax, an aliphatic hydrocarbon wax such as polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax, microcrystalline wax, paraffin wax or Fischer-to-push wax can be preferably used.

  The wax particle dispersion is prepared by heating, melting, and dispersing wax in ion exchange water in an aqueous medium to which a surfactant is added.

  The dispersed particle diameter of the wax is 20% to 200 nm for the 16% diameter (PR16), 40 to 300 nm for the 50% diameter (PR50), and 84% diameter (PR84) for the volume particle diameter cumulative distribution when integrated from the small particle diameter side. It is preferable that emulsified and dispersed to a size of 400 nm or less and PR84 / PR16 of 1.2 to 2.0, with particles of 200 nm or less being 65% by volume or more and particles exceeding 500 nm being 10% by volume or less.

  Preferably, the 16% diameter (PR16) is 20 to 100 nm, the 50% diameter (PR50) is 40 to 160 nm, the 84% diameter (PR84) is 260 nm or less, and PR84 / PR16 is 1.2 to 1.8. It is preferable that particles of 150 nm or less are 65 volume% or more and particles exceeding 400 nm are 10 volume% or less.

  More preferably, the 16% diameter (PR16) is 20 to 60 nm, the 50% diameter (PR50) is 40 to 120 nm, the 84% diameter (PR84) is 220 nm or less, and PR84 / PR16 is 1.2 to 1.8. It is preferable that particles of 130 nm or less are 65 volume% or more, and particles exceeding 300 nm are 10 volume% or less.

  When the core particles are formed by mixing and aggregating the resin particle dispersion, the colorant particle dispersion, and the wax particle dispersion, the first resin particles, the shape adjusting resin particles, and the colorant particles can be uniformly aggregated. . There is an effect of reducing particles floating in water without being taken into core particles.

  PR16 is greater than 200 nm, 50% diameter (PR50) is greater than 300 nm, PR84 is greater than 400 nm, PR84 / PR16 is greater than 2.0, particles of 200 nm or less are less than 65% by volume, and particles greater than 500 nm If it exceeds 10% by volume, the wax particles that are not taken into the core particles and float in water tend to increase. Furthermore, the amount of wax that is exposed and released on the surface of the toner base obtained by fusing the shell resin particles to the core particles increases, filming on the photoreceptor, and adhesion of low melting point components in the toner to the carrier (spent toner). And the handling property in development tends to decrease.

  When PR16 is smaller than 20 nm, 50% diameter (PR50) is smaller than 40 nm, and PR84 / PR16 is smaller than 1.2, the load increases during emulsification dispersion, heat generation tends to increase, and productivity tends to decrease. It becomes. It is difficult to maintain the dispersed state of the wax particles, and reaggregation of the wax tends to occur during standing.

  A rotating body in which a wax melt obtained by melting the wax at a wax concentration of 40 wt% or less is rotated at high speed through a fixed gap with a fixed gap in a medium to which a dispersant maintained at a temperature equal to or higher than the melting point of the wax is added. The wax particles can be finely dispersed by emulsifying and dispersing by the action of high shear force generated by the above.

  3 and 4, a gap of about 0.1 mm to 10 mm is provided on the wall of the tank having a constant capacity, and the rotating body is 30 m / s or more, preferably 40 m / s or more, more preferably 50 m / s or more. By rotating at a high speed, a strong shearing force acts on the aqueous system, and an emulsified dispersion having a fine particle size can be obtained. The water temperature is heated above the melting point of the wax. The treatment liquid can be formed by a treatment for about 30 seconds to 5 minutes.

  A rotating body that rotates at a speed of 30 m / s or more, preferably 40 m / s or more, more preferably 50 m / s or more, with a gap of about 1 to 100 μm provided to a fixed stationary body as shown in FIGS. By adding a strong shearing force action, a fine dispersion can be prepared.

  Compared with a disperser such as a homogenizer, particles having a small particle size and a narrow particle size distribution can be formed. Further, even if the particles are left for a long time, the fine particles forming the dispersion liquid do not re-aggregate and can maintain a stable dispersion state, and the storage stability of the particle size distribution is improved.

  When the melting point of the wax is as high as 95 ° C. or higher, a molten liquid is prepared by setting the heating temperature to be equal to or higher than the melting point of the wax by setting a high pressure state. Alternatively, the wax is dissolved in an oily solvent. This solution is obtained by dispersing fine particles in water together with a surfactant and a polymer electrolyte using the disperser shown in FIGS. 3, 4, 5, and 6, and then evaporating the oily solvent by heating or decompressing. .

The particle size can be measured using a Horiba laser diffraction particle size measuring device (LA920), a Shimadzu laser diffraction particle size measuring device (SALD2100), or the like.
(3) Resin Examples of the resin fine particles of the toner of the present embodiment include a thermoplastic binder resin. Specifically, styrenes such as styrene, parachlorostyrene and α-methylstyrene, acrylic monomers such as methyl acrylate, ethyl acrylate, n-propyl acrylate, lauryl acrylate and 2-ethylhexyl acrylate , Methacrylic monomers such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, and other carboxyl groups such as acrylic acid, methacrylic acid, maleic acid and fumaric acid Homopolymers such as unsaturated polyvalent carboxylic acid-based monomers possessed as, copolymers obtained by combining two or more of these monomers, or mixtures thereof.

  As polymerization initiators, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2 , 2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile and other azo or diazo polymerization initiators, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and its salt, 2,2′-azobis (2-amidinopropane) salt, etc.), peroxide compounds and the like.

  The resin particle content in the resin particle dispersion is usually 5 to 50% by weight, preferably 10 to 40% by weight.

  The glass transition point of the resin particles constituting the core particles in order to eliminate the presence of particles that float without being agglomerated in the formation of core particles by agglomeration reaction with wax and colorant, and to form particles with a sharp particle size distribution is The structure which is 45 degreeC-60 degreeC and a softening point is 90 degreeC-140 degreeC is preferable. More preferably, the glass transition point is 45 ° C to 55 ° C, the softening point is 90 ° C to 135 ° C, and still more preferably, the glass transition point is 45 ° C to 52 ° C, and the softening point is 90 ° C to 130 ° C. preferable.

  Moreover, as a preferable structure of the resin particles, a structure in which the weight average molecular weight (Mw) is 10,000 to 60,000, and the ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5 to 6 is used. preferable. It is preferable that the weight average molecular weight (Mw) is 10,000 to 50,000 and the ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5 to 3.9. More preferably, the weight average molecular weight (Mw) is 10,000 to 30,000, and the ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5 to 3. The coarsening of the core particles can be prevented, and particles having a narrow particle size distribution can be efficiently generated. In addition, low-temperature fixability is possible, and further, there is an effect that the image gloss can be made constant by reducing the change of the image gloss to the fixing temperature. Normally, since the glossiness of an image increases as the fixing temperature rises, the glossiness of the image fluctuates due to a change in fixing temperature, and it is necessary to control the temperature of the fixing severely. However, with this configuration, the effect of little fluctuation in image glossiness can be obtained even when the fixing temperature varies.

  When the glass transition point of the resin particles is lower than 45 ° C., the core particles are coarsened. Storage stability and heat resistance are reduced. When it is higher than 60 ° C., the low-temperature fixability deteriorates. When Mw is smaller than 10,000, the core particles are coarsened. Storage stability and heat resistance are reduced. If it exceeds 60,000, the low-temperature fixability deteriorates. When Mw / Mn is larger than 6, the shape of the core particles is not stable, tends to be indefinite, and irregularities remain on the particle surface, resulting in poor surface smoothness.

  The resin particles used for the core particles are preferably 60 wt% or more, more preferably 70 wt% or more, still more preferably 80 wt% or more based on the total toner resin.

  Moreover, in the structure which fuse | melts a shell resin particle to a core particle to a core particle, and forms a resin melt | fusion layer, as a characteristic of the shell resin particle, a glass transition point is 55 to 75 degreeC, and a softening point is 140 degreeC. ˜180 ° C., weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is 50,000 to 500,000, ratio Mw / Mn of weight average molecular weight (Mw) to number average molecular weight (Mn) is 2 to 10 The structure which is is preferable. More preferably, the glass transition point is 60 ° C to 70 ° C, the softening point is 145 ° C to 180 ° C, the Mw is 80,000 to 500,000, and the Mw / Mn is 2 to 7. More preferably, the glass transition point is 65 ° C to 70 ° C, the softening point is 150 ° C to 180 ° C, Mw is 120,000 to 500,000, and Mw / Mn is 2 to 5.

  The aim is to improve durability, high-temperature offset resistance, and separation between the copy paper and the fixing roller by promoting fusion to the surface of the core particles and increasing the softening point. If the glass transition point of the shell resin particles is lower than 55 ° C., secondary aggregation tends to occur. Moreover, storage stability deteriorates. When it is higher than 75 ° C., the heat-fusibility to the core particle surface is lowered, and the uniform adhesion is lowered. When the softening point of the shell resin particles is lower than 140 ° C., durability, high-temperature offset resistance, and separation properties are deteriorated. When it is higher than 180 ° C., glossiness and translucency are lowered. By making the molecular weight distribution close to monodisperse by reducing Mw / Mn, the thermal fusion of the shell resin particles to the surface of the core particles can be performed uniformly. When the Mw of the shell resin particles is less than 50,000, durability, high temperature non-offset property, and separation between the copy paper and the fixing roller are deteriorated. If it exceeds 500,000, the low-temperature fixability, glossiness, and translucency are lowered.

  The molecular weights of the polymer dispersant, resin, wax and toner are values measured by gel permeation chromatography (GPC) using several types of monodisperse polystyrene as standard samples.

  The apparatus is HLC8120GPC series manufactured by Tosoh Corporation, the column is TSKgel super HM-H H4000 / H3000 / H2000 (6.0 mm ID-150 mm × 3), eluent THF (tetrahydrofuran), flow rate 0.6 mL / min, sample concentration 0 .1%, injection amount 20 μL, detector RI, measurement temperature 40 ° C., pre-measurement treatment was performed by dissolving the sample in THF and allowing it to stand overnight, followed by filtration with a 0.45 μm membrane filter to remove additives such as silica. The resin component is measured. The measurement conditions are conditions in which the molecular weight distribution of the target sample is included in a range in which the logarithm of the molecular weight and the count number are linear in a calibration curve obtained with several types of monodisperse polystyrene standard samples.

  The softening point of the polymer dispersant and the binder resin is measured by a constant load extrusion type capillary rheometer flow tester (CFT500) manufactured by Shimadzu Corporation.

First, a sample is filled in a cylinder, heated from the surroundings and melted, and a certain pressure is applied from above by a piston. The molten sample is extruded through a die having a narrow hole (diameter 1 mm, length 1 mm), and the fluidity of the sample, that is, the melt viscosity is determined from the flow rate (cm ³ / g).

  First, a heating furnace surrounding the cylinder and die is provided and set to 50 ° C. Fill the cylinder with 1 g of sample. Hold at 50 ° C. for 2.5 min without applying load. A load is applied to remove air from the sample. At this time, the length of the piston coming out of the heating furnace is set to about 12 to 15 mm. When the total holding time reaches 5 minutes, the temperature rise is started.

A load of 9.8 × 10 ⁵ N / m ² is applied to the piston, and the piston is heated at a heating rate of 6 ° C./min. When the sample starts to melt, the downward movement of the piston begins. When the movement of the piston stops, the temperature rise and pressurization are stopped.

  At this time, the viscosity at each temperature can be measured from the relationship with the temperature rise temperature characteristic in the relationship between the moving amount of the descending piston and the temperature.

  FIG. 11 shows a flow curve. The horizontal axis shows the temperature, and the vertical axis shows the image of the piston movement. At the time of A, it is a region of the solid state of the sample, and as the temperature rises thereafter, A to B are transition regions, and the sample is deformed by receiving a compressive load, and the internal voids gradually decrease. B is a temperature at which the internal voids disappear and a single transparent body having a uniform appearance with a non-uniform stress distribution is obtained.

  B to C are regions where there is no clear change in the piston position within a finite time, and it is difficult for the sample to flow out of the die, and this region includes the rubbery elastic region of the sample.

  C is defined as a temperature at which the sample starts to flow (outflow start temperature (Tfb)) at a temperature at which the sample starts to flow and the piston starts to descend.

  The region from C to D through E is the flow region where the sample clearly flows out of the die, where E is the point where the sample has finished flowing out.

  The softening point of the binder resin is defined by the melting temperature in the 1/2 method (softening point Ts ° C.). Specifically, the softening point is defined as the temperature at which the piston moves 50% from the outflow start temperature with respect to the total movement distance of the piston from the outflow start temperature to the outflow end temperature.

  11, the temperature at which the piston starts to descend (temperature at which the sample flows) is first measured. This is the outflow start temperature (Tfb). The piston position at this time is read and made the minimum value (Smin).

Thereafter, as the temperature rises, the sample continues to flow out of the die, and the temperature at the outflow end point E at which the outflow of the sample is completed and the position of the piston are read and set as the outflow end point (Smax).
1/2 of the difference between the outflow end point (Smax) and the minimum value (Smin) is obtained (X = (Smax−Smin) / 2), and the temperature at the position of the point D where X and the minimum value Smin of the curve are added is calculated. calculate. This is the melting temperature (softening point Ts ° C.) in the 1/2 method.

  Use a differential scanning calorimeter (TA Instruments, Q100 type (a genuine electric refrigerator is used for cooling)) for the glass transition point of the polymer dispersant and binder resin. N2) After turning on the power at a flow rate of 50 ml / min, set the temperature in the measurement cell to 30 ° C, leave it in that state for 1 hour, and then put 10 mg ± 2 mg of the sample to be measured as a sample amount in a genuine aluminum pan The aluminum pan containing the sample was put into the measuring instrument. Thereafter, the temperature was maintained at 5 ° C. for 5 minutes, and the temperature was increased to 150 ° C. at a temperature increase rate of 1 ° C./min. For the analysis, “Universal Analysis Version 4.0” attached to the apparatus was used. In the graph, it refers to the temperature at the intersection of the extension of the baseline below the glass transition point and the tangent that indicates the maximum slope from the peak rise to the peak apex.

In measuring the thermal properties of these resins, it is necessary to extract the solid content of the resin particles from the emulsion obtained by emulsion polymerization. As a method for extracting the solid content of the resin particles from the emulsion, a configuration in accordance with the toner aggregation step is performed. First, 2 ml of 1N NaOH is added to 20 g of the emulsion, 6 g of magnesium sulfate and 20 g of ion-exchanged water are added, and then the temperature is raised to 85 ° C. and heated for 1 hour. Thereafter, the mixture is cooled, 0.5 ml of 1N HCl is added, filtered, the precipitated sample is dried, and the molecular weight, softening point, glass transition point, etc. of the obtained polymer are measured.
(4) Colorant As the black pigment of the colorant (pigment) used in the present embodiment, carbon black is preferably used. The DBP oil absorption (ml / 100 g) of carbon black is preferably 45 to 70. For example, Mitsubishi Chemical Corporation # 52 (particle size 27 nm, DBP oil absorption 63 ml / 100 g), # 50 (28 nm, 65 ml / 100 g), # 47 (23 nm, 64 ml / 100 g), # 45 (same as above) 24 nm, 53 ml / 100 g), # 45L (24 nm, 45 ml / 100 g), Cabot REGAL 250R (35 nm, 46 ml / 100 g), REGAL 330R (25 nm, 65 ml / 100 g), MOGULL (24 nm) , 60 ml / 100 g). More preferred are # 45, # 45 and REGAL250R.

  The DBP oil absorption is a quantitative representation of the chain aggregate state (structure) of the particles, and is expressed by a primary structure by chemical bonding and a secondary structure by physical bonding by van der Waals force.

DBP oil absorption (JISK6217) was measured by putting 20 g (Ag) of sample dried at 150 ° C. ± 1 ° C. for 1 hour into a mixing chamber of an absorber meter (manufactured by Brabender, spring tension 2.68 kg / cm), After setting the limit switch to about 70% of the maximum torque in advance, the mixer is rotated. At the same time, DBP (specific gravity 1.045 to 1.050 g / cm ³ ) is added from the automatic burette at a rate of 4 ml / min. As the end point is approached, the torque increases rapidly and the limit switch is turned off. The DBP oil absorption (= Bx100 / A) (ml / 100 g) per 100 g of the sample is determined from the DBP amount (Bml) added so far and the sample weight.

  Examples of pigments used as color toners include yellow pigments, C.I. I. Acetoacetic acid arylamide monoazo yellow pigments such as C.I. Pigment Yellow 1, 3, 74, 97 or 98; I. Acetoacetic acid arylamide disazo yellow pigments such as C.I. Pigment Yellow 12, 13, 14, and 17; I. Solven Yellow 19, 77, 79 or C.I. I. Disperse Yellow 164 is blended, and C.I. I. Benzimidazolone pigments of CI Pigment Yellow 93, 180 and 185 are preferred.

  Examples of magenta pigments include C.I. I. Red pigments such as CI Pigment Red 48, 49: 1, 53: 1, 57, 57: 1, 81, 122, 5; I. Red dyes such as Solvent Red 49, 52, 58 and 8 can be preferably used.

  Examples of cyan pigments include C.I. I. A blue dyed pigment of phthalocyanine and its derivatives such as Pigment Blue 15: 3 can be preferably used. The addition amount is preferably 3 to 8 parts by weight with respect to 100 parts by weight of the binder resin.

In addition, the particle diameter has taken the arithmetic mean diameter by a SEM electron microscope. The particle size of carbon black is preferably 20 to 40 nm. Preferably the particle size is 20-35 nm. When the particle diameter is larger than 35 nm, the coloring power tends to decrease. When the particle diameter is smaller than 20 nm, dispersion in the liquid tends to be difficult.
(5) External additive In this embodiment, inorganic fine powder is mixed and added as an external additive. External additives include silica, alumina, titanium oxide, zirconia, magnesia, ferrite, magnetite and other metal oxide fine powders, barium titanate, calcium titanate, titanates such as strontium titanate, barium zirconate, zircon Zirconates such as calcium acid and strontium zirconate, or mixtures thereof are used. The external additive is hydrophobized as necessary.

  Examples of the silicone oil-based material to be treated by the external additive include dimethyl silicone oil, methyl hydrogen silicone oil, methyl phenyl silicone oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, methacryl-modified silicone oil, and alkyl-modified silicone oil. An external additive treated with at least one of fluorine-modified silicone oil, amino-modified silicone oil, and chlorophenyl-modified silicone oil is preferably used. Examples thereof include SH200, SH510, SF230, SH203, BY16-823 or BY16-855B manufactured by Toray Dow Corning Silicone.

  For the treatment, the external additive and the material such as silicone oil are mixed with a mixer such as a Henschel mixer (FM20B manufactured by Mitsui Mining Co., Ltd.), the method of spraying the silicone oil-based material onto the external additive, the silicone oil as the solvent There is a method of preparing by dissolving or dispersing a system material, mixing with an external additive, and then removing the solvent. The silicone oil-based material is preferably blended in an amount of 1 to 20 parts by weight with respect to 100 parts by weight of the external additive.

  As silane coupling agents, dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane, allylphenyldichlorosilane, benzylmethylchlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, Vinyltriacetoxysilane, divinylchlorosilane, dimethylvinylchlorosilane, or the like can be preferably used. The silane coupling agent treatment is a dry treatment in which the vaporized silane coupling agent is reacted with the external additive made into a cloud by stirring or the like, or a silane coupling agent in which the external additive is dispersed in a solvent is dropped. It is processed by a wet method or the like.

  It is also preferable to treat the silicone oil-based material after the silane coupling treatment.

  The external additive having positive electrode chargeability is treated with aminosilane, amino-modified silicone oil or epoxy-modified silicone oil.

  Moreover, in order to improve hydrophobic treatment, the combined use of treatment with hexamethyldisilazane, dimethyldichlorosilane, or other silicone oil is also preferable. For example, it is preferable to treat with at least one of dimethyl silicone oil, methylphenyl silicone oil, and alkyl-modified silicone oil.

  Moreover, it is also preferable to treat the surface of the external additive with one or more selected from the group of fatty acid esters, fatty acid amides, fatty acids and fatty acid metal salts (hereinafter referred to as fatty acids). Surface-treated silica or titanium oxide fine powder is more preferable.

  Examples of fatty acids or fatty acid metal salts include caprylic acid, capric acid, undecylic acid, lauric acid, myristylic acid, parimitic acid, stearic acid, behenic acid, montanic acid, laccellic acid, oleic acid, erucic acid, sorbic acid, linoleic acid, etc. Is mentioned. Of these, fatty acids having 12 to 22 carbon atoms are preferred.

Moreover, as a metal which comprises a fatty-acid metal salt, aluminum, zinc, calcium, magnesium, lithium, sodium, lead, or barium is mentioned, Among these, aluminum, zinc, or sodium is preferable. Particularly preferred are aluminum distearate (Al (OH) (C ₁₇ H ₃₅ COO) ₂ ) or aluminum monostearate (Al (OH) ₂ (C ₁₇ H ₃₅ COO)), etc. Is preferred. Having an OH group can prevent overcharging and suppress poor transfer. Further, it is considered that the processability with the external additive is improved during the treatment.

  The aliphatic amide has 16 to 24 carbon atoms such as palmitic acid amide, palmitoleic acid amide, stearic acid amide, oleic acid amide, arachidic acid amide, eicosenoic acid amide, behenic acid amide, erucic acid amide or ligrinoceric acid amide. Saturated or monovalent unsaturated aliphatic amides are preferably used.

  Examples of fatty acid esters include esters comprising higher alcohols having 16 to 24 carbon atoms and higher fatty acids having 16 to 24 carbon atoms such as stearyl stearate, palmityl palmitate, behenyl behenate or stearyl montanate, butyl stearate, Esters consisting of higher fatty acids having 16 to 24 carbon atoms and lower monoalcohols such as isobutyl behenate, propyl montanate or 2-ethylhexyl oleate, or fatty acid pentaerythritol monoester, fatty acid pentaerythritol triester, or fatty acid trimethylol Propane ester or the like is preferably used.

  Materials such as hydroxystearic acid derivatives, polyhydric alcohol fatty acid esters such as glycerin fatty acid ester, glycol fatty acid ester or sorbitan fatty acid ester are preferred, and one kind or a combination of two or more kinds can also be used.

  As a preferred form of the surface treatment, it is also preferred that the surface of the external additive to be treated is treated with a coupling agent and / or polysiloxane such as silicone oil and then treated with a fatty acid or the like. This is because a uniform treatment is possible as compared with the case where the fatty acid of the hydrophilic silica is simply treated, and the toner can be highly charged and the fluidity when added to the toner is improved. In addition, the above-described effects can be obtained even in a configuration in which fatty acid or the like is treated together with a coupling agent and / or silicone oil.

  Dissolve fatty acid in a hydrocarbon-based organic solvent such as toluene, xylene or hexane, and mix it with an external additive such as silica, titanium oxide, alumina, etc. It is produced by depositing, applying a surface treatment, and then removing the solvent and performing a drying treatment.

  The mixing ratio of the polysiloxane and the fatty acid is preferably 1: 2 to 20: 1. When the ratio is higher than 1: 2, the amount of charge of the external additive increases, and the image density tends to decrease, and charge-up tends to occur in two-component development. When the amount of fatty acid or the like is less than 20: 1, the effect on transfer loss and reverse transferability tends to decrease.

  At this time, the ignition loss of the external additive whose surface is treated with fatty acid or the like is preferably 1.5 to 25% by weight. More preferably, it is 5-25 weight%, More preferably, it is 8-20 weight%. When the loss on ignition of the external additive is less than 1.5% by weight, the function of the treating agent is not sufficiently exhibited, and the effect of improving the chargeability and transferability does not appear. When the ignition loss of the external additive is more than 25% by weight, the untreated agent is present, which adversely affects the developability and durability.

  Unlike the conventional pulverization method, the surface of the toner base particles produced according to the present invention is formed from only a resin, which is advantageous in terms of charge uniformity. This is because compatibility with the external additive used is important.

  A configuration in which 1 to 6 parts by weight of an external additive having an average particle diameter of 6 nm to 200 nm is externally added to 100 parts by weight of the toner base particles is preferable. When the average particle diameter is smaller than 6 nm, filming on the suspended particles and the photoreceptor tends to occur. The reverse transfer during transfer tends to occur. If it exceeds 200 nm, the fluidity of the toner tends to deteriorate. When the amount is less than 1 part by weight, the fluidity of the toner tends to deteriorate. Reverse transfer during transfer tends to occur easily. When the amount is more than 6 parts by weight, the floating particles and the filming on the photoreceptor tend to occur easily.

  Further, an external additive having an average particle diameter of 6 nm to 20 nm is added to 0.5 to 2.5 parts by weight with respect to 100 parts by weight of the toner base particles, and an external additive having an average particle diameter of 20 nm to 200 nm is added to 100 parts by weight of the toner base particles. On the other hand, a configuration in which at least 0.5 to 3.5 parts by weight is externally added is also preferable. By using an external additive that is functionally separated by this configuration, the charge imparting property and the charge retention property are improved, and a margin can be further taken against reverse transfer, dropout, and toner scattering during transfer. At this time, the ignition loss of the external additive having an average particle diameter of 6 nm to 20 nm is preferably 0.5 to 20% by weight, and the ignition loss of the average particle diameter of 20 nm to 200 nm is preferably 1.5 to 25% by weight. . By increasing the loss on ignition with an average particle size of 20 nm to 200 nm more than the loss on ignition of an external additive with an average particle size of 6 nm to 20 nm, it is effective for reverse transfer during transfer and voiding. Is demonstrated.

  By specifying the loss on ignition of the external additive, a margin can be taken against reverse transfer, dropout, and scattering during transfer. It is possible to improve the handling property in the developing unit and increase the uniformity of the toner density.

  If the loss on ignition with an average particle size of 6 nm to 20 nm is less than 0.5% by weight, the transfer margin for reverse transfer and hollow out tends to be narrow. If it exceeds 20% by weight, the surface treatment becomes uneven, and there is a tendency for variation in charging to occur. The ignition loss is preferably 1.5 to 17% by weight, more preferably 4 to 10% by weight.

  If the loss on ignition with an average particle size of 20 nm to 200 nm is less than 1.5% by weight, the transfer margin for reverse transfer and hollow out tends to be narrow. If it exceeds 25% by weight, the surface treatment becomes uneven, and there is a tendency for variation in charging to occur. The ignition loss is preferably 2.5 to 20% by weight, more preferably 5 to 15% by weight.

  The external additive having an average particle diameter of 6 nm to 20 nm and an ignition loss of 0.5 to 20% by weight is 0.5 to 2 parts by weight with respect to 100 parts by weight of the toner base particles, and the average particle diameter is 20 nm to 0.5 to 3.5 parts by weight of an external additive having 100 nm and an ignition loss of 1.5 to 25% by weight based on 100 parts by weight of the toner base particles, an average particle diameter of 100 to 200 nm, and an ignition loss of 0 A configuration in which at least 0.5 to 2.5 parts by weight of an external additive of 1 to 10% by weight with respect to 100 parts by weight of toner base particles is externally added is also preferable. The structure of the external additive with the function of specifying the average particle size and loss on ignition improves the charge imparting property, charge retention, reverse transfer during transfer, and improvement of voids. Effective for removal.

  Further, an external additive having a positive charging property with an average particle diameter of 6 nm to 200 nm and an ignition loss of 0.5 to 25% by weight is further added to 0.2 to 1.5 parts by weight based on 100 parts by weight of the toner base particles. It is also preferable to perform the external addition treatment.

  The effect of adding an external additive having a positive charging property can prevent the toner from being overcharged during long-term continuous use, thereby further extending the developer life. Furthermore, the effect of suppressing scattering during transfer due to overcharging can also be obtained. In addition, the spent on the carrier can be prevented. If the amount is less than 0.2 parts by weight, it is difficult to obtain the effect. If it exceeds 1.5 parts by weight, fogging during development increases. The ignition loss is preferably 1.5 to 20% by weight, more preferably 5 to 19% by weight.

  The average particle diameter is a value obtained by taking an enlarged photograph with an SEM (scanning electron microscope) and obtaining an average value of major and minor axes of about 100 particles.

  For loss on drying (% by weight), about 1 g of a sample is placed in a container that has been dried, allowed to cool, and precisely weighed in advance, and weighed accurately. Dry in a hot air dryer (105 ° C ± 1 ° C) for 2 hours. After cooling in a desiccator for 30 minutes, the weight is precisely weighed and calculated from the following formula.

  Loss on drying (% by weight) = [Loss on drying (g) / Amount of sample (g)] × 100.

  For ignition loss, about 1 g of a sample is placed in a magnetic crucible that has been dried, allowed to cool, and precisely weighed in advance, and weighed accurately. Ignite for 2 hours in an electric furnace set to 500 ° C. After standing to cool in a desiccator for 1 hour, its weight is precisely weighed and calculated from the following formula.

  Loss on ignition (% by weight) = [Loss on ignition (g) / Sample amount (g)] × 100.

  Further, the moisture absorption amount of the treated external additive is preferably 1% by weight or less. Preferably it is 0.5 weight% or less, More preferably, it is 0.1 weight% or less, More preferably, it is 0.05 weight% or less. When the moisture absorption amount of the external additive is more than 1% by weight, the chargeability is lowered and filming on the photoreceptor during durability is caused. The water adsorption amount was measured with a continuous vapor adsorption device (BELSORP18: Nippon Bell Co., Ltd.) for the water adsorption device.

  The degree of hydrophobicity is determined by methanol titration, weighing 0.2 g of the product to be tested in 50 ml of distilled water charged in a 250 ml beaker. At the tip, methanol is dropped from a burette that is invaded in the liquid until the total amount of the external additive is wet. At that time, slowly stir slowly with an electromagnetic stirrer. The degree of hydrophobicity is calculated by the following equation from the amount of methanol a (ml) essential for complete wetting.

Hydrophobicity = (a / (50 + a)) × 100 (%).
(6) Toner powder physical properties In this embodiment, toner base particles containing a binder resin, a colorant and a wax have a volume average particle size of 3 to 6 μm, a volume-based variation coefficient of 10 to 25%, and a number-based distribution. The toner particles having a particle diameter of 2.0 to 3.63 μm in the toner have a content of 10 to 85% by number, and toner particles having a particle diameter of 3.5 to 4.53 μm in the volume-based distribution are 25 to 75 volume%. Toner particles having a particle size of 6.06 μm or more in a volume-based distribution are contained in an amount of 5% by volume or less,
The volume% of toner particles having a particle diameter of 3.5 to 4.53 μm in the volume-based distribution is V34, and the number% of toner particles having a particle diameter of 3.5 to 4.53 μm in the number-based distribution is P34. P34 / V34 is preferably in the range of 0.4 to 2.2.

  Preferably, the toner base particles have a volume average particle size of 3 to 5 μm, a volume-based variation coefficient of 10 to 20%, and a content of toner particles having a particle size of 2.0 to 3.63 μm in a number-based distribution is 15 ~ 85% by number, toner particles having a particle size of 3.5 to 4.53 μm in a volume-based distribution are 30 to 65% by volume, toner particles having a particle size of 6.06 μm or more in a volume-based distribution are 2 volumes %, And P34 / V34 is preferably in the range of 0.5 to 1.5.

  More preferably, the toner base particles have a volume average particle size of 3 to 5 μm, a volume-based variation coefficient of 10 to 16%, and a content of toner particles having a particle size of 2.0 to 3.63 μm in a number-based distribution. 25 to 85% by number, toner particles having a particle size of 3.5 to 4.53 μm in the volume-based distribution are 40 to 60% by volume, toner particles having a particle size of 6.06 μm or more in the volume-based distribution are It is preferably contained at 0.5% by volume or less, and P34 / V34 is preferably in the range of 0.5 to 0.9.

  In a high resolution image quality, and further in a tandem configuration, it is possible to prevent reverse transfer during transfer and prevent voids and achieve both oil-less fixing. The toner particle size distribution affects toner fluidity, image quality, storage stability, filming on a photoreceptor, a developing roller, and a transfer body, aging characteristics, transferability, and in particular, multi-layer transfer in a tandem system. In addition, it affects the high temperature non-offset property and glossiness in oilless fixing. In a toner containing a wax for realizing oil-less fixing, the amount of fine powder affects the compatibility with tandem transferability.

  When the volume average particle size exceeds 6 μm, it is impossible to achieve both image quality and transfer. When the volume average particle size is less than 3 μm, it tends to be difficult to convey toner particles during development.

  If the content of toner particles having a particle size of 2.0 to 3.63 μm in the number-based distribution is less than 10% by number, it tends to be impossible to achieve both image quality and transfer. When it exceeds 85% by number, it tends to be difficult to convey the toner during development. Further, filming on the photosensitive member, the developing roller, and the transfer member may occur. Furthermore, fine powder tends to be offset at high temperature because of its high adhesion to the heat roller. In the tandem system, toner aggregation tends to be strong, and a transfer failure of the second color tends to occur during multilayer transfer. An appropriate range is required.

  When toner particles having a particle size of 3.5 to 4.53 μm in the volume-based distribution are less than 25% by volume, the image quality tends to deteriorate. If it exceeds 75% by volume, it tends to be impossible to achieve both image quality and transfer.

  If toner particles having a particle size of 6.06 μm or more in the volume reference distribution are contained in excess of 5% by volume, the image quality is deteriorated, which tends to cause transfer defects.

  When P34 / V34 is smaller than 0.4, the amount of fine powder present becomes excessive, and the fluidity, transferability, and background fog tend to deteriorate. When it is larger than 2.2, there are many large particles and the particle size distribution becomes broad, and the image quality tends not to be improved.

  The purpose of defining P34 / V34 can be used as an index for making toner particles small and narrowing the particle size distribution.

  The coefficient of variation is the standard deviation of the toner particle size divided by the average particle size. This is based on the particle diameter measured using a Coulter counter (Coulter). The standard deviation is expressed as the square root of the value obtained by dividing the square of the difference from the average value of each measured value when (n-1) is measured when n particle systems are measured.

  In other words, the coefficient of variation represents the extent of the particle size distribution, and if the coefficient of variation of the volume particle size distribution is less than 10% or the coefficient of variation of the number particle size distribution is less than 10%, it is difficult to produce, This will increase costs. When the variation coefficient of the volume particle size distribution is larger than 25% or the variation coefficient of the number particle size distribution is larger than 28%, the particle size distribution becomes broad, the toner cohesion becomes stronger, and filming or transfer to the photosensitive member is performed. It tends to cause defects.

  Further, the shape index of the toner is preferably 1.25 to 1.55, more preferably 1.33 to 1.46, and still more preferably 1.35 to 1.42. When the shape index of the toner is smaller than 1.25, the crazing property by the rubber blade in which the spherical shape progresses is deteriorated. On the other hand, when the toner shape index is larger than 1.55 and the indefinite shape is advanced, the transferability is lowered. Tend to be.

  Further, when the shape index of the toner base particles is SC and the volume average particle diameter is d50 (μm), the product of SC and d50 (SC × d50) is preferably 3.9 to 7.3. Preferably it is 4.0-6.6, More preferably, it is 4.1-5.7.

  By prescribing this numerical value, the cleaning performance with the rubber blade tends to deteriorate when the spheroidization of the shape proceeds when the particle shifts to a small particle size. In addition, when the particles shift to a large particle size, if the shape progresses to an irregular shape, there is a tendency to deteriorate transferability and image quality. In the case of a small particle size, the shape is shifted to an irregular shape. In order to maintain the cleaning property and to maintain the image quality by shifting the shape to a spherical shape in the case of a large particle size particle, the product of SC and d50 is set within a certain range. When SC × d50 is smaller than 3.9, the cleaning property tends to be deteriorated. When SC × d50 is larger than 7.3, the image quality tends to be deteriorated.

  The particle size distribution is measured by using a Coulter Counter TA-II type (Coulter Counter Co., Ltd.) and connecting an interface (manufactured by Nikkaki Co., Ltd.) for outputting the number distribution and volume distribution and a personal computer. The electrolyte solution is a surfactant (sodium lauryl sulfate) added to a concentration of 1% by weight. About 2 mg of the toner to be measured is added to about 50 ml, and the electrolyte solution in which the sample is suspended is dispersed by an ultrasonic disperser for about 3 minutes. Processing was performed, and an aperture of 70 μm was used with a Coulter counter TA-II type. In the 70 μm aperture system, the particle size distribution measurement range is 1.26 μm to 50.8 μm, but the region less than 2.0 μm is not practical because the measurement accuracy and measurement reproducibility are low due to the influence of external noise and the like. Therefore, the measurement area was set to 2.0 μm to 50.8 μm.

  The shape index was obtained by the following formula using a real surface view microscope (VE7800) manufactured by Keyence Corporation, taking about 100 toner base particles magnified 1000 times, measuring the maximum length and the projected area (d : Maximum length of toner particles, A: projected area of toner particles).

SC (shape factor) = π · d ² / (4 · A)
(7) Oilless Color Fixation In this embodiment, the present invention is suitably used for an electrophotographic apparatus having a fixing process of an oilless fixing configuration in which oil is not used as a toner fixing means. As the heating means, electromagnetic induction heating is a preferable configuration from the viewpoint of shortening the warm-up time and saving energy. A heating and pressurizing unit having at least a magnetic field generating unit, a rotary heating member having at least a heat generation layer and a release layer generated by electromagnetic induction, and a rotary pressurizing member forming a fixed nip with the rotary heating member; In this configuration, a transfer medium such as copy paper on which toner is transferred is passed between the rotary heating member and the rotary pressure member, and is fixed. As a feature thereof, the warm-up time of the rotary heating member is very fast compared to the case where a conventional halogen lamp is used. For this reason, since the copying operation is started in a state where the temperature of the rotary pressure member is not sufficiently raised, low temperature fixing and a wide range of offset resistance are required.

  As a configuration, a configuration using a fixing belt in which a heating member and a fixing member are separated is also preferably used. As the belt, a heat resistant belt such as a nickel electroformed belt or a polyimide belt having heat resistance and deformability is preferably used. In order to improve releasability, it is preferable to use silicone rubber, fluororubber, or fluororesin as the surface layer.

  In such fixing, conventionally, release oil has been applied to prevent offset. If the toner has releasability without using oil, it is not necessary to apply release oil. Therefore, by using the toner of this embodiment, low temperature fixing and a wide range of offset resistance can be realized without using oil, and high color translucency can be obtained. Further, the toner can be prevented from being overcharged, and toner flying due to the charging action with the heating member or the fixing member can be suppressed.

(1) 39.7mol% in carrier production example in terms of MnO, 9.9 mol% in terms of MgO, in 0.8 mol% wet ball mill 49.6Mol% and SrO terms in terms _{of Fe} 2 _{O 3,} and ground for 10 hours, mixed Then, it was kept at 950 ° C. for 4 hours, and calcination was performed. This was pulverized with a wet ball mill for 24 hours, then granulated with a spray dryer, dried, and held in an electric furnace at 1270 ° C. for 6 hours in an atmosphere with an oxygen concentration of 2%, followed by firing. Then, it was crushed and further classified to obtain a ferrite particle core material having an average particle diameter of 50 μm and a saturation magnetization of 65 emu / g when the applied magnetic field was 3000 oersted.

Next, R ₁ and R ₂ represented by (Chemical Formula ₂ ) are methyl groups, that is, (CH ₃ ) ₂ SiO _2/2 units are 15.4 mol%, and R ₃ represented by (Chemical Formula 3) is a methyl group, that is, A fluorine-modified silicone resin was obtained by reacting 250 g of polyorganosiloxane having 82.6 mol% of (CH ₃ ) ₂ SiO _3/2 units and 21 g of CF ₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃ . Further, 100 g of the fluorine-modified silicone resin in terms of solid content and 10 g of aminosilane coupling agent (γ-aminopropyltriethoxysilane) were weighed and dissolved in 300 cc of toluene solvent.

  Coating was performed on 10 kg of the ferrite particles by stirring the coating resin solution for 20 minutes using an immersion drying type coating apparatus. Thereafter, baking was performed at 260 ° C. for 1 hour to obtain carrier CA1.

Next, examples of the toner of the present invention will be described, but the present invention is not limited to these examples.
(2) Preparation of resin particle dispersion (Table 1) shows the characteristics of the resin particles obtained in the prepared resin particle dispersion (RL1, RL2, RL3, RH1, RH2, RH3, RH4, RH5, RH6). Show.

  “Mn” is the number average molecular weight, “Mw” is the weight average molecular weight, “Mz” is the Z average molecular weight, and “Mw / Mn” is the ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn). , “Mz / Mn” is the ratio Mz / Mn of the Z average molecular weight (Mz) to the number average molecular weight (Mn), “Mp” is the peak value of molecular weight, Tg (° C.) is the glass transition point, and Ts (° C.) is softened. Represents a point.

(a) Preparation of Resin Particle Dispersion RL1 A monomer liquid composed of 240.1 g of styrene, 59.9 g of n-butyl acrylate, and 8 g of acrylic acid was added to 440 g of ion-exchanged water (Sanyo). Kasei Co., Ltd .: Nonipol 400) 7.2 g, anionic surfactant (Daiichi Kogyo Seiyaku, Neogen S20-F (20 wt% aqueous solution concentration)) 24 g (substantial anion amount 4.8 g), dodecanethiol 8 g were used. Then, 4.5 g of potassium persulfate was added thereto, and emulsion polymerization was performed at 78 ° C. for 3 hours. Thereafter, aging treatment was further performed at 90 ° C. for 4 hours to prepare a resin particle dispersion RL1 in which resin particles were dispersed. The pH of the resin dispersion at this time was 1.8.

  (Table 2) shows the nonionic amount (g), the anionic amount (g), and the ratio of the nonionic amount (% by weight) to the total amount of the surfactant used in each resin particle dispersion. In a liquid using an anionic surfactant (Daiichi Kogyo Seiyaku, Neogen S20-F (solid content: 20 wt% concentration)), the weight ratio in Table 2 represents the actual anion amount ratio.

  (Table 3) and (Table 4) show the blending amounts of acrylic acid, potassium persulfate, etc. used in each resin particle dispersion based on the preparation of resin particle dispersion RL1 in the emulsion polymerization of each resin particle dispersion. Show. Potassium persulfate parts by weight indicate parts by weight with respect to 100 parts by weight of the monomer component.

(3) Preparation of pigment dispersion
(a) Preparation of pigment particle dispersion CBS1 In a 1 L beaker, 308 g of ion-exchanged water and 11.2 g of dispersant A (EP1) of polypropylene glycol ethylene oxide adduct were weighed, and the solid content of the surfactant was measured with a magnetic stirrer. Stir until dissolved. 80 g of carbon black CB1 was added to the aqueous dispersant A, and further stirred with a magnetic stirrer for 10 minutes. Next, the contents were transferred to a 1 L tall beaker and dispersed using a homogenizer (manufactured by IKA, T-25) at a rotation speed of 9500 rpm for 10 minutes. This dispersion was further dispersed with a disperser (TK Fillmix: 56-50 manufactured by Tokushu Kika Co., Ltd.). The produced dispersion was designated as pigment particle dispersion CBS1. The pigment concentration was about 20% by weight.
The colorant (pigment) used in (Table 5), the surfactant of the polypropylene glycol ethylene oxide adduct used in (Table 6), and the polymer surfactant used in (Table 7) are shown.

  Based on the adjustment conditions of the pigment particle dispersion CBS1, the colorant (pigment) used in each colorant dispersion, the conditions of the dispersant and pigment dispersion used are shown in (Table 8). The numbers in parentheses of Dispersant A and Dispersant B are the weight parts of the surfactant based on 100 parts by weight of the colorant particles. The dispersant na1 is Eleminol NA100 and na4 is Eleminol NA400 (manufactured by Sanyo Chemical Industries).

  Table 9 shows the ion-exchanged water, colorant weight (g), material dispersant amount (g), and pigment concentration (wt%) used when producing the dispersion.

(4) Preparation of wax dispersion
(a) Preparation of Wax Particle Dispersion WA11 FIG. 3 is a schematic view of a stirring and dispersing device (TK Film Mix manufactured by Tokushu Kika Co., Ltd.), and FIG. Reference numeral 801 denotes an outer tank, in which cooling water is injected from 808 and discharged from 807. Reference numeral 802 denotes a dam plate that stops the liquid to be processed, and a hole is formed in the center portion. The processed liquid is sequentially taken out through 805 from here. Reference numeral 803 denotes a rotating body that rotates at a high speed and is fixed to the shaft 806 and can rotate at a high speed. A hole of about 1 to 5 mm is formed on the side surface of the rotating body, and the liquid to be processed can be moved. The tank is 1 L, and about half of the liquid to be treated is charged. The speed MAX of the rotating body can be up to 50 m / s.

  The diameter of the rotating body is 52 mm, and the inner diameter of the tank is 56 mm. Reference numeral 804 denotes a raw material inlet for continuous processing. Sealed during high-pressure processing or batch processing.

Under normal pressure in the tank, 30 g of wax (W1) and 150 g of wax (W11) were charged into 402 g of ion-exchanged water in which 18 g of dispersant A (EP1) of polypropylene glycol ethylene oxide adduct was dissolved, and the speed of the rotating body Was 30 min / s for 5 min, and then the rotational speed was increased to 50 m / s for 2 min. A wax particle dispersion WA11 was formed.
(Table 10), (Table 11), and (Table 12) show the wax materials and their characteristics used in the preparation of the wax particle dispersion, respectively.

  Based on the adjustment conditions of the wax particle dispersion WA11, the wax used in each wax particle dispersion wax particle dispersion (WA11 to WA20) and the types and characteristics of the used dispersants are shown in Table 13. “First wax” and “second wax” indicate the wax material charged in the wax particle dispersion, and the value in parentheses at the end of the symbol indicating the wax indicates the blending weight ratio (weight ratio) of the wax. Represent. The numbers in parentheses of Dispersant A and Dispersant B are the weight parts of the surfactant based on 100 parts by weight of the wax particles.

  Table 14 shows the ion exchange water amount (g), wax weight (g), dispersant amount (g), and wax concentration (wt%) used when producing the wax dispersion. Moreover, when using wax W13, W14, W15, the inside of the tank is pressurized to 0.4 MPa.

(5) Preparation of toner base
(a) Preparation of toner base B1 (STD)
204 g of the first resin particle dispersion RL1, 50 g of the carbon black particle dispersion CBS1, and 80 g of the wax particle dispersion WA11 are placed in a cylindrical 2 L glass container equipped with a thermometer, a cooling pipe, a pH meter, and a stirring blade. Then, 480 ml of ion-exchanged water was added, and mixed for 10 minutes using a homogenizer (manufactured by IKA: Ultra Tarrax T25) to prepare a mixed particle dispersion.

  Thereafter, 1N NaOH was added to the obtained mixed dispersion to adjust the pH to 11.5, and then 300 g of a 23 wt% magnesium sulfate aqueous solution was added and stirred for 10 min. Thereafter, the temperature was raised from 20 ° C. to 90 ° C. at a rate of 1 ° C./min, followed by heat treatment for 2 hours to obtain a core particle dispersion in which the liquid became transparent. The obtained core particle dispersion had a pH of 9.1.

  The pH of the transparent core particle dispersion was adjusted to 6.5 and heat-treated for 2 hours. The purpose is to remove the minute irregularities remaining on the surface of the core particles by shifting the pH to the acidic side and continue heating while preventing so-called secondary aggregation in which the core particles aggregate. This is to promote the aggregation of core particles that have not been aggregated, promote the adhesion of the shell resin to be fused in the next step, and narrow the particle size distribution of the generated particles.

  Thereafter, 110 g of a shell resin particle dispersion RH3 having a pH adjusted to 8 is added in a state where the water temperature is 92 ° C., and after the dropwise addition, heat treatment is performed for 3.5 hours to obtain particles in which the shell resin particles are fused. It was.

Then, after cooling, the reaction product (toner base material) was filtered and washed with ion-exchanged water three times. The toner base thus obtained was dried at 40 ° C. for 6 hours using a fluid dryer.
(b) Preparation of toner base B2 (STD)
204 g of the first resin particle dispersion RL1, 50 g of the carbon black particle dispersion CBS2, and 80 g of the wax particle dispersion WA12 are placed in a cylindrical 2 L glass container equipped with a thermometer, a cooling pipe, a pH meter, and a stirring blade. Then, 480 ml of ion-exchanged water was added, and mixed for 10 minutes using a homogenizer (manufactured by IKA: Ultra Tarrax T25) to prepare a mixed particle dispersion.

  Thereafter, 1N NaOH was added to the obtained mixed dispersion to adjust the pH to 11, and then 300 g of a 23 wt% magnesium sulfate aqueous solution was added and stirred for 10 min. Thereafter, the temperature was raised from 20 ° C. to 90 ° C. at a rate of 1 ° C./min, followed by heat treatment for 2 hours to obtain a core particle dispersion in which the liquid became transparent. The obtained core particle dispersion had a pH of 8.4.

  The pH of the transparent core particle dispersion was adjusted to 7.0 and heat-treated for 1.5 hours. Thereafter, the pH of the core particle dispersion was readjusted to 5.5.

  Thereafter, 110 g of a shell resin particle dispersion RH3 having a pH adjusted to 9 was added in a state where the water temperature was set to 92 ° C., and heat treatment was performed for 2.5 hours after the completion of dropping to obtain particles in which the shell resin particles were fused. .

Then, after cooling, the reaction product (toner base material) was filtered and washed with ion-exchanged water three times. The toner base thus obtained was dried at 40 ° C. for 6 hours using a fluid dryer.
(c) Preparation of toner base B4 (V2)
204 g of the first resin particle dispersion RL1, 41 g of the carbon black particle dispersion CBS4, and 50 g of the wax particle dispersion WA14 are placed in a cylindrical 2 L glass container equipped with a thermometer, a cooling pipe, a pH meter, and a stirring blade. Then, 410 ml of ion-exchanged water was added and mixed for 10 minutes using a homogenizer (manufactured by IKA: Ultra Tarrax T25) to prepare a mixed particle dispersion.

  Thereafter, 1N NaOH was added to the obtained mixed dispersion to adjust the pH to 11.5 and stirred for 10 minutes. Thereafter, when the temperature was raised from 20 ° C. at a rate of 1 ° C./min and reached 80 ° C. (the pH value of the mixed dispersion was 8.4), the pH value of the aqueous solution was adjusted to 5.4 with a concentration of 23% by weight. 267 g of magnesium sulfate aqueous solution is continuously added dropwise over a required time of 60 minutes, heated for 0.5 hours, heated to 90 ° C., and heated for 1.5 hours to obtain a core particle dispersion in which the liquid became transparent. It was. The obtained core particle dispersion had a pH of 8.8. The pH of the core particle dispersion was adjusted to 5.8 and heated for 1 hour.

  Thereafter, 80 g of a shell resin particle dispersion RH5 having a pH adjusted to 7.5 is added in a state where the water temperature is set to 92 ° C., and heat treatment is performed for 4 hours after the dropping is completed to obtain particles in which the shell resin particles are fused. It was.

  Then, after cooling, the reaction product (toner base material) was filtered and washed with ion-exchanged water three times. The toner base thus obtained was dried at 40 ° C. for 6 hours using a fluid dryer.

  Toner bases B3, B5, B8, and B14 to B17 were evaluated by trial production by changing the wax particle dispersion or the colorant particle dispersion based on the conditions of (a) B1.

  The toner bases B10, B18, and B19 were evaluated as prototypes by changing the wax particle dispersion or the colorant particle dispersion based on the condition (b) B2.

  The toner bases B6 and B7 were evaluated by trial production by changing the wax particle dispersion or the colorant particle dispersion based on the condition (c) B4.

  Table 15 shows the composition of each toner matrix prepared as an example of toner matrix preparation.

  Table 16 shows the characteristics obtained with the toner base prepared. d50 (μm) represents the volume average particle diameter, volume variation coefficient, and shape index of the toner base particles.

  In the process of agglomerating and fusing resin particles, pigment particles, and wax particles to produce toner, the agglomeration property of the core particles whether or not pigment fine particles and wax fine particles are surrounded by resin fine particles This confirmation can be made by taking out the reaction solution during the aggregation and fusion reaction at regular intervals and subjecting it to centrifugation. If the pigment particles and the wax particles are taken into the toner, the reaction liquid is separated into two solid-liquid layers when centrifuged, and the supernatant becomes colorless and transparent. When the wax particles are not taken into the toner, the supernatant liquid becomes cloudy. When the pigment particles are not taken into the toner, the supernatant liquid shows the hue of the pigment. For example, cyan toner indicates cyan, and black toner indicates black.

For the core particle aggregating property, the dispersion sampled during the core particle agglutination reaction was diluted with an equal amount of ion-exchanged water, placed in a test tube, and placed in a centrifuge at 3000 min ⁻¹ for 5 minutes. It shows a state in which the turbidity of the centrifuged supernatant is visually determined.

  B1 to B8 and B14 to B17 have a small particle size and a small particle size when the supernatant liquid becomes transparent in 1.5 hours (h) to 3.5 hours (h) after the liquid temperature of the core particle dispersion reaches 90 degrees. Particles with a narrow distribution are obtained.

  B10 became substantially transparent in about 5 to 6 hours, but the particle size distribution slightly increased and the particle size distribution tends to be slightly widened. In image evaluation, there is a tendency that fogging and transfer character skipping are slightly larger than those of other B1 to B8 and B14 to B17 toners.

In B18 and B19, floating wax particles and pigment particles that do not participate in poor aggregation remain, and the turbidity tends not to disappear.
(6) External additive Next, examples of the external additive will be described. (Table 17) shows each material and its characteristic about the external additive (S1, S2, S3, S4, S5, S6, S7, S8, S9) used in the present Example.

In the case of processing with a plurality of types of the processing material 1 and the processing material 2, () shows the blending weight ratio of each processing material. “5-minute value” and “30-minute value” represent the charge amount ([μC / g]), which were measured by the blow-off method of frictional charge with an uncoated ferrite carrier. Specifically, in an environment of 25 ° C. and 45 RH%, 50 g of carrier and 0.1 g such as silica are mixed in a 100 ml polyethylene container, and stirred for 5 minutes and 30 minutes at a speed of 100 min ⁻¹ by longitudinal rotation. 0.3 g was collected and measured by blowing with nitrogen gas at 1.96 × 10 ⁴ [Pa] for 1 minute.

For negative chargeability, the 5-minute value is preferably −100 to −800 μC / g, and the 30-minute value is preferably −50 to −600 μC / g. A high charge amount of silica can exhibit such characteristics with a small amount of addition.
(7) Toner Composition and External Addition Processing Next, a toner composition and an example of external addition processing will be described. Table 18 shows the material composition of the toner according to the present invention prepared as a toner preparation example. Unblended indicates no addition. Note that the value in parentheses at the end of the symbol indicating the external additive in the external additive column represents the blending amount (parts by weight) of the external additive with respect to 100 parts by weight of the toner base. In the external addition process (Henschel mixer FM20B, manufactured by Mitsui Mining Co., Ltd.), stirring blade Z0S0 type, rotation speed 2000 min ⁻¹ , treatment time 5 min, and input amount 1 kg were performed.

  FIG. 1 is a cross-sectional view showing a configuration of an image forming apparatus for forming a full-color image used in this embodiment. In FIG. 1, the outer casing of the color electrophotographic printer is omitted. The transfer belt unit 17 includes a transfer belt 12, a first color (yellow) transfer roller 10Y made of an elastic body, a second color (magenta) transfer roller 10M, a third color (cyan) transfer roller 10C, and a fourth color (black). Transfer roller 10K, drive roller 11 made of aluminum roller, second transfer roller 14 made of elastic body, second transfer driven roller 13, belt cleaner blade 16 for cleaning the toner image remaining on the transfer belt 12, and opposed to the cleaner blade A roller 15 is provided at a position to be used. At this time, the distance from the first color (Y) transfer position to the second color (M) transfer position is 70 mm (second color (M) transfer position to third color (C) transfer position, third color (C). The fourth color (K) transfer position is the same distance from the transfer position), and the peripheral speed of the photosensitive member is 125 mm / s.

The transfer belt 12 is used by kneading a conductive filler in an insulating polycarbonate resin and forming a film with an extruder. In the present example, a film obtained by adding 5 parts by weight of conductive carbon (for example, ketjen black) to 95 parts by weight of polycarbonate resin (for example, Iupilon Z300, manufactured by Mitsubishi Gas Chemical) as the insulating resin was used. Further, the surface is coated with a fluororesin, the thickness is about 100 μm, the volume resistance is 10 ⁷ to 10 ¹² Ω · cm, and the surface resistance is 10 ⁷ to 10 ¹² Ω / □. This is also for improving dot reproducibility. This is to effectively prevent slack and charge accumulation due to long-term use of the transfer belt 12, and the coating of the surface with a fluororesin is effective for toner filming on the surface of the transfer belt after long-term use. This is to prevent it. If the volume resistance is less than 10 ⁷ Ω · cm, retransfer is likely to occur, and if it is greater than 10 ¹² Ω · cm, the transfer efficiency deteriorates.

The first transfer roller with carbon conductive urethane foam roller having an outer diameter of 8 mm, the resistance value is ¹⁰ 2 ^{~10 6 Ω.} During the first transfer operation, the first transfer roller 10 is pressed against the photoreceptor 1 with a pressing force of 1.0 to 9.8 (N) via the transfer belt 12, and the toner on the photoreceptor is transferred onto the belt. Is done. If the resistance value is smaller than 10 ² Ω, retransfer is likely to occur. If it exceeds 10 ⁶ Ω, transfer defects are likely to occur. If it is less than 1.0 (N), transfer defects occur, and if it is greater than 9.8 (N), transfer character omission occurs.

The second transfer roller 14 is a carbon conductive foamed urethane roller having an outer diameter of 10 mm, and the resistance value is 10 ² to 10 ⁶ Ω. The second transfer roller 14 is pressed against the transfer roller 13 via the transfer belt 12 and a transfer medium 19 such as paper or OHP. The transfer roller 13 is configured to be driven to rotate by the transfer belt 12. In the second transfer, the second transfer roller 14 and the counter transfer roller 13 are pressed against each other with a pressing force of 5.0 to 21.8 (N), and the toner is transferred from the transfer belt onto the recording material 19 such as paper. The If the resistance value is smaller than 10 ² Ω, retransfer is likely to occur. If it exceeds 10 ⁶ Ω, transfer defects are likely to occur. If it is smaller than 5.0 (N), transfer failure occurs. If it is larger than 21.8 (N), the load increases and jitter tends to occur.

  Four sets of image forming units 18Y, 18M, 18C, and 18K for each color of yellow (Y), magenta (M), cyan (C), and black (K) are arranged in series as shown in the figure.

  Each of the image forming units 18Y, 18M, 18C, and 18K is composed of the same constituent members except for the developer contained therein, so that the Y image forming unit 18Y will be described to simplify the description, and the units for other colors The description of is omitted.

  The image forming unit is configured as follows. 1 is a photosensitive member, 3 is a pixel laser signal light, 4 is a developing roller having an outer diameter of 10 mm made of aluminum having a magnet having a magnetic force of 1200 gauss, and is opposed to the photosensitive member with a gap of 0.3 mm. Rotate in the direction of. 6 is a stirring roller that stirs the toner and carrier in the developing device and supplies them to the developing roller. The composition ratio of the carrier and the toner is read by a magnetic permeability sensor (not shown) and is supplied from a toner hopper (not shown) in a timely manner. A metal magnetic blade 5 regulates the magnetic brush layer of the developer on the developing roller. The developer amount is 150 g. The gap was 0.4 mm. Although the power supply is omitted, a DC voltage of −500 V and an AC voltage of 1.5 kV (pp) and a frequency of 6 kHz are applied to the developing roller 4. The peripheral speed ratio between the photoreceptor and the developing roller was 1: 1.6. The mixing ratio of toner and carrier was 93: 7, and the developer amount in the developing unit was 150 g.

  A charging roller 2 having an outer diameter of 10 mm made of epichlorohydrin rubber is applied with a DC bias of -1.2 kV. The surface of the photoreceptor 1 is charged to −600V. 8 is a cleaner, 9 is a waste toner box, and 7 is a developer.

  The paper is transported from below the transfer unit 17 so that the paper 19 is fed by a paper feed roller (not shown) to the nip portion where the transfer belt 12 and the second transfer roller 14 are pressed. A conveyance path is formed.

  The toner on the transfer belt 12 is transferred to the paper 19 by +1000 V applied to the second transfer roller 14, and includes a fixing roller 201, a pressure roller 202, a fixing belt 203, a heating medium roller 204, and an induction heater unit 205. It is conveyed to the fixing unit and fixed there.

  FIG. 2 shows the fixing process. A belt 203 is placed between the fixing roller 201 and the heat roller 204. A predetermined load is applied between the fixing roller 201 and the pressure roller 202, and a nip is formed between the belt 203 and the pressure roller 202. An induction heater unit 205 including a ferrite core 206 and a coil 207 is provided on the outer peripheral surface of the heat roller 204, and a temperature sensor 208 is provided on the outer surface.

  The belt has a structure in which 30 μm of Ni is used as a base, silicone rubber is 150 μm thereon, and further, PFA tube is 30 μm.

  The pressure roller 202 is pressed against the fixing roller 201 by a pressure spring 209. The recording material 19 having the toner 210 moves along the guide plate 211.

  A fixing roller 201 as a fixing member is a silicone rubber having a rubber hardness (JIS-A) of 20 degrees according to JIS standard on the surface of an aluminum hollow roller metal core 213 having a length of 250 mm, an outer diameter of 14 mm, and a thickness of 1 mm. An elastic layer 214 having a thickness of 3 mm is provided. A silicone rubber layer 215 is formed thereon with a thickness of 3 mm and has an outer diameter of about 26 mm. It receives a driving force from a driving motor (not shown) and rotates at 125 mm / s.

  The heat roller 204 is a hollow pipe having a thickness of 1 mm and an outer diameter of 20 mm. The surface temperature of the fixing belt was controlled to 170 ° using a thermistor.

  The pressure roller 202 as a pressure member has a length of 250 mm and an outer diameter of 20 mm. This is provided with a 2 mm thick elastic layer 217 made of silicone rubber having a rubber hardness (JIS-A) of 55 degrees according to JIS standards on the surface of a hollow roller metal core 216 made of aluminum having an outer diameter of 16 mm and a thickness of 1 mm. . The pressure roller 202 is rotatably installed, and a nip width of 5.0 mm is formed between the pressure roller 202 and the fixing roller 201 by a spring-loaded spring 209 on one side 147N.

  The operation will be described below. In the full color mode, all of the first transfer rollers 10 of Y, M, C, and K are pushed up and press the photoreceptor 1 of the image forming unit via the transfer belt 12. At this time, a DC bias of +800 V is applied to the first transfer roller. An image signal is sent from the laser beam 3 and is incident on the photoreceptor 1 whose surface is charged by the charging roller 2 to form an electrostatic latent image. The toner on the developing roller 4 that rotates in contact with the photoreceptor 1 visualizes the electrostatic latent image formed on the photoreceptor 1.

  At this time, the image forming speed of the image forming unit 18Y (125 mm / s equal to the peripheral speed of the photoconductor) and the moving speed of the transfer belt 12 are 0.5 to 1.5% slower than the transfer belt speed. Is set to

  In the image forming process, the Y signal light 3Y is input to the image forming unit 18Y, and image formation with Y toner is performed. Simultaneously with the image formation, the first transfer roller 10Y causes the Y toner image to be transferred from the photoreceptor 1Y to the transfer belt 12. At this time, a DC voltage of +800 V was applied to the first transfer roller 10Y.

  With a time lag between the first color (Y) first transfer and the second color (M) first transfer, M signal light 3M is input to the image forming unit 18M, and image formation with M toner is performed. Simultaneously with the image formation, the M toner image is transferred from the photosensitive member 1M to the transfer belt 12 by the action of the first transfer roller 10M. At this time, the first color (Y) toner is formed and the M toner is transferred. Similarly, image formation with C (cyan) and K (black) toners is performed, and simultaneously with image formation, a YMCK toner image is formed on the transfer belt 12 by the action of the first transfer rollers 10C and 10K. This is a so-called tandem method.

On the transfer belt 12, the four color toner images are positioned and overlapped to form a color image. After the transfer of the last K toner image, the four color toner images are collectively transferred to the paper 19 fed from a paper feed cassette (not shown) at the same time by the action of the second transfer roller 14. At this time, the transfer roller 13 was grounded, and a DC voltage of +1 kV was applied to the second transfer roller 14. The toner image transferred to the paper was fixed by a pair of fixing rollers 201 and 202. The paper was then discharged out of the apparatus through a pair of discharge rollers (not shown). The residual transfer toner remaining on the intermediate transfer belt 12 was cleaned by the action of the cleaning blade 16 to prepare for the next image formation.
(Example of image evaluation)
Next, an example of image output evaluation for toner and two-component developer will be described. Here, an image forming apparatus is used, and a two-component developer of toner and carrier is subjected to a running durability test of 100,000 sheets with an A4 plate output to measure the charge amount and the image density, and the non-output sample Evaluation was made on background fogging in the image area, uniformity on the entire solid image, transferability (letter skipping during printing, reverse transfer, transfer omission), and toner filming. Image density (ID) evaluation measured the black solid part using the reflection densitometer RD-914 made from Macbeth Division of Kollmorgen Instruments Corporate.

The mixing ratio of the toner and the carrier was 8:92 (% by weight). In an environment of 25 ° C. and 45 RH%, a carrier of 46 g and a toner of 4 g were mixed in a 100 ml polyethylene container and stirred for 10 minutes at a speed of 100 min ⁻¹ by longitudinal rotation.

The charge amount was measured by the blow-off method of frictional charging with the ferrite carrier. Specifically, in an environment of 25 ° C. and a relative humidity of 45% RH, 0.3 g of a sample for durability evaluation was collected and measured by blowing with nitrogen gas at 1.96 × 10 ⁴ Pa for 1 minute.
(Table 19) shows, for each of the two-component developers (DB1 to DB19) used in this example, a configuration of toner and carrier as the two-component developer, and a 100,000 sheet running durability test using A4 size paper. Results of implementation and evaluation are shown.

  If the fog level is 0.01 or less, the fog level is a better level “A”, and if it is 0.01 or less and 0.03 or less, the fog level is slightly increased “B”, 0. If it is greater than 0.03, it indicates a problematic level “C”.

  As for the uniformity of the entire solid image, when a solid image sample is taken on the entire surface in A4 size, if the image density partially changes and the image density difference is small, the comparison between “A” and “A”. If the image density difference is a level that can be seen a little, “B” is indicated. If the image density difference is partially noticeable, “B” is indicated.

  For character skipping at the time of transfer, when the characters “轟, 議, 魏” are printed, evaluation is performed with the state of toner present around the line. If the toner present around the line is low and the level is “ “A” is indicated by “B” if the toner level is slightly present around the line, and “C” if the toner level is high near the line.

  In reverse transfer, when two or more color image samples are printed, the first color toner is transferred from the photoconductor to the transfer belt, and then the second color toner is transferred from the photoconductor to the transfer belt. A phenomenon in which part of the first color toner adheres to the second color photoconductor. In the evaluation, the toner of the first color adheres to the photoconductor of the second color, is removed from the photoconductor by the craning blade, and the amount of toner collected in the waste toner box is visually evaluated. “A” if the first and second color toners are hardly mixed, “B” if the first and second color toners are a little mixed, clearly mixed. For example, “C”.

  In the middle of transfer, a pattern “+” where lines intersect is printed, and the presence state of toner is evaluated at this intersection. If the level at which the toner is present at the intersection, “A” is indicated, “B” if the level at which there is no toner at the intersection is “B”, and “C” if no toner is present at the intersection. .

Two-component developer DB1~DB8, DB14~DB17 was performed 100,000 sheets running durability test A4 size paper (Panasonic designated paper (104g ^{/ m} 2)). Regarding the image density before and after the running test, the image density showed a stable characteristic with little change of 1.4 or more. The toner filming on the photoconductor was at a level where there was no practical problem. In addition, toner filming on the transfer belt was at a level causing no practical problem. Further, no transfer belt cleaning failure occurred. Even in a full-color image in which the three colors overlap, no paper wrapping around the fixing belt occurred.

    Further, with respect to the non-image area fogging and the entire surface solid image uniformity, the two-component developer according to the present invention was free from the occurrence of ground fogging in the non-image area, and did not scatter toner, and had high resolution. Further, the uniformity when taking the entire solid image at the time of development was also good. With regard to transferability (character skipping during transfer, reverse transfer, and transfer skipping), skipping and the like were at a level that has no practical problem. In addition, no transfer failure occurred even in a full-color image in which the three colors overlapped. The transfer efficiency was about 95%.

  In DB10, the background fogging of the non-image part is slightly generated, and the character skip at the time of transfer is slightly generated.

  On the other hand, in DB18 and DB19, phenomena such as a decrease in image density and an increase in fogging, which are considered to be influenced by loose wax particles and pigment particles that do not participate in aggregation, have occurred.

  Table 20 shows the evaluation results for the minimum fixing temperature, the offset property at high temperature, the high-temperature storage stability, and the paper wrapping property around the fixing belt.

The minimum fixing temperature and the offset generation temperature at high temperatures are A4 size paper (Panasonic specified by a fixing device using a solid image with an adhesion amount of 1.0 mg / cm ^{2 at} a process speed of 125 mm / s and a belt not coated with oil. It measured on the conditions of paper (104g / m < ² >).

In the storage stability test at high temperature, the state of the toner after standing at 50 ° C. for 24 hours was evaluated. In the table, “A” indicates that the evaluation result is good, thermal aggregation does not occur after standing at high temperature, and the powder state is maintained. "B" indicates that the level of evaluation is slightly inferior to A, the aggregate in 30 g / cm ² or more little load loosened. “C” indicates that there is a problem, and after standing at a high temperature, the agglomerates are formed and the agglomerates do not collapse unless a load of 300 g / cm ² or more is applied.

  The film transmittance for OHP was measured using a spectrophotometer U-3200 (Hitachi) to measure the transmittance of 700 nm light.

  In the fixing property evaluation, TB1 to TB8 exhibited a low temperature fixing property of 145 ° C. or lower and a high temperature non-offset property of 190 ° C. or higher. The high-temperature storage stability was also good. However, TB10 has a tendency that the high-temperature non-offset property is slightly lower than other toners.

  In TB18 and TB14, both the low-temperature fixability and the high-temperature non-offset property were poor, and a sufficient fixable temperature range could not be obtained.

  The present invention is useful not only for an electrophotographic system using a photoconductor but also for a system in which a paper or a toner containing a conductive material is directly deposited on a substrate as a wiring pattern.

Sectional drawing which shows the structure of the image forming apparatus used in the Example of this invention Sectional drawing which shows the structure of the fixing unit used in the Example of this invention Schematic of the stirring and dispersing apparatus used in the examples of the present invention View from above of the stirring and dispersing device used in the examples of the present invention Schematic of the stirring and dispersing apparatus used in the examples of the present invention View from above of the stirring and dispersing device used in the examples of the present invention Schematic of the stirring and dispersing apparatus used in the examples of the present invention View from above of the stirring and dispersing device used in the examples of the present invention Schematic of the stirring and dispersing apparatus used in the examples of the present invention View from above of the stirring and dispersing device used in the examples of the present invention Schematic of calculation method of softening point (melting temperature in 1/2 method) of binder resin by flow tester of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging roller 3 Laser signal light 4 Developing roller 5 Blade 10 1st transfer roller 12 Transfer belt 13 Drive tension roller 14 2nd transfer roller 17 Transfer belt unit 18B, 18C, 18M, 18Y Image forming unit 18 Image forming unit Group 201 Fixing roller 202 Pressure roller 203 Fixing belt 205 Induction heater unit 206 Ferrite core 207 Coil 801 Outer tank 802 Dam plate 803 Rotating body 806 Shaft 807 Cooling water discharge port 808 Cooling water injection port

Claims (32)

A toner comprising at least core particles produced by agglomerating resin particles, colorant particles and wax particles,
A toner containing a polypropylene glycol ethylene oxide adduct in a dispersant used for a colorant particle dispersion in which the colorant particles are dispersed. The toner according to claim 1, wherein the dispersant used in the colorant particle dispersion includes a polypropylene glycol ethylene oxide adduct and a polymer dispersant. The toner according to claim 1, wherein the weight average molecular weight of the hydrophobic group portion of the polypropylene glycol ethylene oxide adduct is 1750 or more and 3850 or less. The toner according to claim 1 or 2, wherein the ethylene oxide in the total molecule of the polypropylene glycol ethylene oxide adduct is 40 wt% or more and 80 wt% or less. The toner according to claim 2, wherein the polymer dispersant is 1 to 25 parts by weight with respect to 100 parts by weight of the colorant particles, and the polypropylene glycol ethylene oxide adduct is 1 to 25 parts by weight with respect to 100 parts by weight of the colorant particles. The toner according to claim 2, wherein the polymer-based dispersant includes a maleic acid-based dispersant or an acrylic acid-based dispersant, and the polymer-based dispersant has a glass transition point of 40 to 150 ° C. The polymer dispersant is at least one selected from a styrene-acrylic acid copolymer, a styrene-maleic acid copolymer, a styrene-maleic acid half ester copolymer, an acrylate-maleic acid copolymer, and salts thereof. The toner according to claim 2, comprising one substance. The toner according to claim 2, wherein the blending weight ratio of the polymer-based dispersant and the polypropylene glycol ethylene oxide adduct is 1:10 to 10: 1. The toner according to claim 1, wherein shell toner particles are further fused to core particles. The wax comprises at least a first wax and a second wax, the endothermic peak temperature of the first wax by DSC (referred to as the melting point Tmw1 (° C.)) is 50 to 90 ° C., and the second wax The toner according to claim 1, wherein the endothermic peak temperature (melting point Tmw2 (° C)) of the wax by DSC method is 80 to 120 ° C. The wax includes at least a first wax and a second wax, and the first wax includes an ester wax composed of at least one of a higher alcohol having 16 to 24 carbon atoms and a higher fatty acid having 16 to 24 carbon atoms. The toner according to claim 1, wherein the second wax contains an aliphatic hydrocarbon wax. The wax includes at least a first wax and a second wax, the first wax includes a wax having an iodine value of 25 or less and a saponification value of 30 to 300, and the second wax is an aliphatic hydrocarbon type The toner according to claim 1, wherein the toner comprises a wax. The toner according to claim 10, wherein the melting point of the second wax is 5 to 50 ° C. higher than the melting point of the first wax. The surfactant used for the resin particle dispersion is a mixture of a nonionic surfactant and an ionic surfactant, and the nonionic surfactant has 50 to 95 wt% with respect to the entire surfactant. Toner. In an aqueous medium, at least a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed are mixed to form a mixed solution. Process,
Adding a flocculant to the mixed solution, and aggregating the resin particles, the colorant particles, and the wax particles to produce core particles,
A method for producing a toner, wherein the dispersant used in the colorant particle dispersion in which the colorant particles are dispersed contains a polypropylene glycol ethylene oxide adduct. A resin particle dispersion liquid in which resin particles are dispersed, a colorant particle dispersion liquid in which colorant particles are dispersed, and a wax particle dispersion liquid in which wax particles are dispersed are mixed to produce a mixed liquid. The toner manufacturing method according to claim 15, wherein the core particles are generated by the adding step. The water temperature of the mixed dispersion obtained by mixing the resin particle dispersion in which the resin particles are dispersed, the colorant particle dispersion in which the colorant particles are dispersed, and the wax particle dispersion in which the wax particles are dispersed reaches the melting point of the wax or higher. The method for producing a toner according to claim 15 or 16, wherein a coagulant is added later. In an aqueous medium, at least a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed are mixed to form a mixed solution. Process,
Adding a flocculant to the mixed solution, and aggregating the resin particles, the colorant particles and the wax particles to produce core particles;
The toner according to claim 15, further comprising a step of shifting the pH in the core particle dispersion liquid in which the core particles in which the resin particles, the colorant particles, and the wax particles are aggregated are dispersed to 0.5 to 5 acid side. Production method. The method further comprises adding a shell resin particle dispersion in which shell resin particles are dispersed to a core particle dispersion containing core particles, and heating to fuse the shell resin particles to the core particles. A method for producing the toner. A step of adding a shell resin particle dispersion in which shell resin particles having a pH value adjusted to an alkaline state are dispersed to a core particle dispersion in which core particles having a pH value of 7 or less and 2 or more are dispersed. 19. A method for producing a toner according to 19. The method for producing a toner according to claim 19 or 20, wherein the shell resin particle dispersion in which the shell resin particles adjusted to an alkaline state are dispersed has a pH value in the range of 7.5 to 10.5. The toner according to any one of claims 19 to 21, which is added by adjusting the pH value of the shell resin particle dispersion in which the shell resin particles are dispersed to an alkaline state equal to or higher than the pH value of the core particle dispersion in which the core particles are dispersed. Production method. The method for producing a toner according to claim 15, wherein the dispersant used in the colorant particle dispersion includes a polypropylene glycol ethylene oxide adduct and a polymer dispersant. The toner production method according to claim 15 or 23, wherein the polypropylene glycol ethylene oxide adduct has a hydrophobic group weight average molecular weight of 1750 or more and 3850 or less. The method for producing a toner according to claim 15 or 23, wherein ethylene oxide in the total molecule of the polypropylene glycol ethylene oxide adduct is 40 wt% or more and 80 wt% or less. The toner production according to claim 23, wherein the polymer dispersant is 1 to 25 parts by weight with respect to 100 parts by weight of the colorant particles, and the polypropylene glycol ethylene oxide adduct is 1 to 25 parts by weight with respect to 100 parts by weight of the colorant particles. Method. The method for producing a toner according to claim 23, wherein the polymer-based dispersant includes a maleic acid-based dispersant or an acrylic acid-based dispersant, and a glass transition point of the polymer-based dispersant is 40 to 150 ° C. The polymer dispersant is at least one selected from a styrene-acrylic acid copolymer, a styrene-maleic acid copolymer, a styrene-maleic acid half ester copolymer, an acrylate-maleic acid copolymer, and salts thereof. 28. A method for producing a toner according to claim 23 or 27, comprising two substances. The method for producing a toner according to claim 23, wherein a blending weight ratio of the polymer dispersant and the polypropylene glycol ethylene oxide adduct is 1:10 to 10: 1. The surfactant used for the resin particle dispersion is a mixture of a nonionic surfactant and an ionic surfactant, and the nonionic surfactant has 50 to 95 wt% with respect to the total surfactant. A method for producing the toner according to the description. At least a magnetic field generating means, a heating member having a rotating action having at least a heat generating layer and a release layer that generate heat by electromagnetic induction, and a pressing member having a rotating action that forms a fixed nip with the heating member. 15. An image comprising a heating and pressurizing unit, and having a fixing process in which a transfer medium on which the toner according to claim 1 is transferred is fixed between the heating member and the pressing member. Forming equipment. At least a magnetic field generating means, a heating member having a rotating action having at least a heat generating layer and a release layer that generate heat by electromagnetic induction, and a pressing member having a rotating action that forms a fixed nip with the heating member. 30. A fixing process comprising a heating and pressing unit, wherein a transfer medium onto which the toner manufactured by the method according to any one of claims 15 to 29 is transferred is fixed between the heating member and the pressing member. An image forming apparatus.

Images