JP2009251472A - Method for manufacturing aggregated particle, aggregated particle, toner, developer, developing device, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing aggregated particles having a particle diameter in a single micron order (1 μm or more and less than 10 μm), a narrow grain size distribution and an aspheric figure, and having both of good cleaning property and good transfer property, and to provide aggregated particles manufactured by the method, a toner and a developer containing the aggregated particles, and a developing device and an image forming apparatus using the developer. <P>SOLUTION: The aggregated particles are manufactured by the method for manufacturing aggregated particles including a dispersion liquid preparation step and an aggregation step. In the dispersion liquid preparation step, a liquid medium containing a polymer dispersant and an objective material to be processed is treated by use of a high-pressure machine having a gradual pressure release mechanism so as to atomize the objective material at a temperature higher by 100°C to 150°C than the outflow initiation temperature of the objective material measured by a flow tester, so as to prepare a dispersion liquid having fine particles of the objective material dispersed in the liquid medium. In the aggregation step, the fine particles contained in the dispersion liquid are aggregated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an aggregated particle manufacturing method, aggregated particle, toner, developer, developing device, and image forming apparatus.

  An electrophotographic image forming apparatus (hereinafter simply referred to as “image forming apparatus”) includes, for example, a photoreceptor, a charging unit, an exposing unit, a developing unit, a transferring unit, a fixing unit, a discharging unit, and a cleaning unit. Including. The image forming apparatus is an apparatus that forms an image on a recording medium by performing a charging process, an exposure process, a developing process, a transfer process, a fixing process, a cleaning process, and a charge eliminating process using the photosensitive member and these means.

  In the charging step, the surface of the photoreceptor is uniformly charged by a charging unit. In the exposure step, the charged photoconductor is exposed by an exposure unit, and an electrostatic latent image is formed on the surface of the photoconductor. In the development step, the electrostatic latent image formed on the surface of the photoreceptor is developed with a developer to form a visible image. Specifically, a visible image is formed on the surface of the photosensitive member by attaching a toner provided with a charge by a developing unit to the electrostatic latent image formed on the surface of the photosensitive member. In the transfer step, the visible image formed on the surface of the photoreceptor is transferred to a recording medium such as paper by a transfer unit. In the fixing step, the transferred visible image is fixed on the recording medium by heating, pressing, or the like by a fixing unit. In the cleaning process, the transfer residual toner remaining on the surface of the photoreceptor after the transfer process is removed by a cleaning unit. In the charge removal step, the charge on the surface of the photosensitive member is removed by the charge removal unit to prepare for the next image formation.

  In recent years, there has been a demand for higher image quality in electrophotography, and research has been conducted on reducing the particle size of toner particles contained in a developer from the viewpoint of dot reproducibility. However, for example, in the reduction of the particle size including the micronization process using a conventional jet mill or the like, the larger the toner particle size, the longer the pulverization energy is required. Moreover, it is difficult to classify fine powder, which is contrary to resource saving and energy saving.

  Therefore, a method for producing toner particles including chemical processes such as a suspension polymerization method and an emulsion aggregation method has been proposed. According to these chemical methods, particles having a particle size of about 5 μm and particles with a well-defined particle size distribution can be obtained, contributing to resource saving and energy saving. However, if toner particles having a particle diameter smaller than 5 μm are obtained with the aim of further improving the image quality, and the toner particles are used as a dry developer, there is a concern that the floating toner particles may adversely affect the human body.

  In order to solve such problems, for example, wet developers have been reviewed. The wet developer is a developer in which toner particles are dispersed in an insulating liquid. When a wet developer is used, generation of powder can be prevented.

  The basic principle of the cleaning process in a wet electrophotographic process using a wet developer is the same as that in the dry electrophotographic process. Specifically, in the cleaning process, the transfer residual toner on the surface of the photoreceptor is removed by scraping with a urethane rubber blade, for example. (For example, refer to page 15 of Patent Document 1) For this reason, toner particles having a spherical shape (hereinafter, also referred to as “spherical toner”) may pass through the blade and deteriorate the cleaning property. The dry toner included includes, for example, the shape of a deformed toner having an irregular particle shape and the shape of a spherical toner, such as a toner prepared by a pulverization method in consideration of the transferability of a spherical toner. A non-spherical toner having a shape in between is used. The wet toner contained in the wet developer is required to have a non-spherical toner shape having both good transferability of the spherical toner and easy scraping with the blade of the irregular toner, like the dry toner.

  In response to such demand, for example, a method for producing submicron particles using a wet pulverization method is disclosed in Patent Document 2, and a method for producing an electrophotographic developer using micron and submicron particle sizes using a high-pressure processing method. Is disclosed in Patent Document 3.

JP 2006-259385 A (page 15) JP 7-313894 A Japanese Patent Laid-Open No. 7-64348

  However, in the method for producing submicron particles using the wet pulverization method disclosed in Patent Document 2, the shape of the particles is too distorted, and the particle sizes using the high-pressure treatment method disclosed in Patent Document 3 are micron and submicron. In the method for producing an electrophotographic developer, particles that are too spherical are produced, and therefore, particles that meet the above-mentioned demand cannot be produced.

  The object of the present invention is a method for producing agglomerated particles having a particle size of a single micron (1 μm or more and less than 10 μm), a narrow particle size distribution, a non-spherical shape, and having both good cleaning properties and good transfer properties. It is to provide an aggregated particle produced by the production method, a toner and a developer containing the aggregated particle, and a developing device and an image forming apparatus using the developer.

The present invention uses a high-pressure machine having a stepwise pressure release mechanism for a liquid medium containing a polymer dispersant and a processed product at a temperature that is 100 ° C. or more and 150 ° C. or less higher than the flow tester outflow start temperature of the processed product. A dispersion preparation step of preparing a dispersion in which the processed product is microparticulated to disperse the processed product fine particles in a liquid medium;
An agglomeration step of aggregating the fine particles contained in the dispersion.

  In the invention, it is preferable that the volume average particle diameter of the fine particles contained in the dispersion liquid is 0.05 μm or more and 0.50 μm or less.

  In the present invention, the volume average particle diameter of the aggregated particles is 4 to 40 times the volume average particle diameter of the fine particles.

  The present invention also provides aggregated particles obtained by the above-described method for producing aggregated particles.

Further, the invention is characterized in that the processed product contains at least a resin.
In the invention, it is preferable that the processed product contains at least a colorant.

Further, the present invention is a toner comprising the aggregated particles.
Further, the present invention is a toner characterized in that the surface of toner base particles is coated with the aggregated particles.

  In the present invention, the glass transition temperature of the resin is 40 ° C. or more and 70 ° C. or less, and the weight average molecular weight of the resin is 10,000 or more and 300,000 or less.

Moreover, this invention is characterized by including a mold release agent.
The present invention also provides a developer comprising the toner.

  According to another aspect of the present invention, there is provided a developing device that develops a latent image formed on an image carrier using the developer to form a toner image.

The present invention also provides an image carrier on which a latent image is formed,
A latent image forming means for forming a latent image on the image carrier;
An image forming apparatus comprising the developing device.

  According to the present invention, in the dispersion preparation step, the liquid medium containing the polymer dispersant and the processed material is removed from the flow tester outflow start temperature of the processed material by using a high-pressure machine having a stepwise pressure release mechanism. The treated product is atomized at a temperature higher than or equal to 150 ° C. and less than or equal to 150 ° C. to prepare a dispersion in which the treated product fine particles are dispersed in a liquid medium. By doing so, it is possible to prepare a dispersion in which fine particles having a particle size of submicron and a narrow particle size distribution are dispersed. Next, the fine particles in the dispersion prepared in the dispersion preparation step are aggregated. By including the polymer dispersant in the dispersion liquid, the fine particles can be aggregated little by little while maintaining appropriate dispersibility in the aggregation process as compared with the case where the dispersion liquid does not contain the polymer dispersant. Therefore, aggregated particles having a non-spherical shape, a narrow particle size distribution, and a single particle size (1 μm or more and less than 10 μm) can be stably produced.

  According to the invention, the volume average particle diameter of the fine particles contained in the dispersion is 0.05 μm or more and 0.50 μm or less. In a liquid medium containing a polymer dispersant, the smaller the fine particles, the more stable and less agglomerated, so if the volume average particle diameter of the fine particles is less than 0.05 μm, the volume average particle diameter of the fine particles is 0.05 μm or more. Compared with the case of the above, fine particles that do not aggregate are likely to remain, and the particle size distribution may not be narrowed. When the volume average particle diameter of the fine particles exceeds 0.50 μm, the agglomerated particles whose volume average particle diameter exceeds a single micron (1 μm or more and less than 10 μm) compared to the case where the volume average particle diameter of the fine particles is 0.50 μm or less. Becomes easier to manufacture. By producing agglomerated particles by agglomerating fine particles having a volume average particle diameter of 0.05 μm or more and 0.50 μm or less, agglomerated particles having a non-spherical shape and a narrow particle size distribution (1 μm or more and less than 10 μm) are obtained. It can be manufactured more stably.

  According to the invention, the volume average particle diameter of the aggregated particles is 4 to 40 times the volume average particle diameter of the fine particles. When the volume average particle size of the aggregated particles is less than 4 times the volume average particle size of the fine particles, the shape difference is smaller than when the volume average particle size of the aggregated particles is 4 times or more the volume average particle size of the fine particles. There is a risk that aggregated particles having a large particle size distribution are produced. If the volume average particle diameter of the aggregated particles exceeds 40 times the volume average particle diameter of the fine particles, aggregated particles having a shape close to a sphere may be produced. When the volume average particle diameter of the aggregated particles is 4 to 40 times the volume average particle diameter of the fine particles, the shape difference between the particles is small, the shape is non-spherical, and the particle size distribution is single micron (1 μm or more) (Less than 10 μm) can be more stably produced.

  Moreover, according to this invention, an aggregated particle is obtained by the manufacturing method of the aggregated particle of this invention. The agglomerated particles produced by the method for producing agglomerated particles of the present invention have a non-spherical shape, a narrow particle size distribution, and a particle size of a single micron (1 μm or more and less than 10 μm). For example, when applied to the electrophotographic field, a developer with uniform performance can be obtained.

  Moreover, according to this invention, the said processed material contains resin at least. When the treated product contains at least a resin, the shape is non-spherical, the particle size distribution is narrow, the particle diameter is single micron (1 μm or more and less than 10 μm), and aggregated particles containing at least the resin can be produced. The aggregated particles can be used as a toner in the electrophotographic field, for example. Further, the aggregated particles can be used as a shell material for capsule particles, thereby greatly expanding the design range of the core material.

  Moreover, according to this invention, the said processed material contains a coloring agent at least. The agglomerated particles produced by the method for producing agglomerated particles of the present invention have a non-spherical shape, a narrow particle size distribution, and a particle size of single micron (1 μm or more and less than 10 μm). , The shape is non-spherical, the particle size distribution is narrow, the particle size is single micron (1 μm or more and less than 10 μm), and aggregated particles containing at least a colorant can be produced. The aggregated particles can be suitably used as, for example, a wet toner.

  According to the invention, the toner includes at least the aggregated particles of the invention. The aggregated particles of the present invention are non-spherical particles having a volume average particle diameter of 3 μm or less and a volume particle size distribution variation coefficient CV of 25% or less. Non-spherical particles are particles having a shape factor SF1 of 130 to 140 and a shape factor SF2 of 120 to 130. SF1 indicates the degree of roundness of the particles. SF2 indicates the degree of unevenness of the particles. In general, the smaller the toner particle size, the more difficult the transfer residual toner on the image carrier is removed by the cleaning blade, so the cleaning performance decreases. The tendency for the cleaning property to decrease as the particle diameter of the toner decreases becomes more prominent as the particle shape of the toner becomes spherical and the unevenness of the particle surface decreases. If the SF1 is less than 130, the shape of the aggregated particles contained in the toner is too round, which may deteriorate the cleaning property. When SF1 exceeds 140, the contact area between the image carrier and the intermediate transfer medium and the toner is larger than when SF1 is 140 or less, and the adhesion between the image carrier and the intermediate transfer medium and the toner is increased. Since it becomes large, the toner becomes difficult to be transferred to the recording medium, and there is a possibility that the transferability is lowered. Further, compared with the case where the shape factor SF1 is 140 or less, the shape of the aggregated particles becomes indefinite, and the aggregated particles have corners. Therefore, if the toner includes the aggregated particles of the present invention, the developer is developed in the developing tank. Aggregated particles rub against each other during idling of the agent, and the agglomerated particles are cracked, whereby fine particles of the agglomerated particles are generated and the particle size distribution may be broadened. If the SF2 is less than 120, the unevenness of the aggregated particle surface is too small and the cleaning property may be deteriorated. When SF2 exceeds 130, the transferability may be lowered, and when the developer is idling, fine particles of the aggregated particles are likely to be generated due to cracking of the aggregated particles, which may lead to a broad particle size distribution.

  When the toner contains the aggregated particles of the present invention, a toner having a single peak, a narrow particle size distribution, a non-spherical shape, and a particle size of single micron (1 μm or more and less than 10 μm) can be realized. When an image is formed with such a toner, image loss due to poor cleaning can be prevented and transferability can be improved in both dry and wet processes, so that a high-quality image can be stably formed. be able to. Further, in the dry process, the toner particles are easily collected by the filter in the image forming apparatus and the toner particles can be prevented from floating, and thus can be used without adversely affecting the human body.

  According to the present invention, the toner covers the surface of the toner base particles with the aggregated particles of the present invention. By covering the surface of the toner base particles with the aggregated particles of the present invention, when the toner base particles contain a release agent, it is possible to suppress problems caused by including the release agent, The toner can be a storable and durable toner, and a remarkable effect can be exhibited particularly when the toner in which the surface of the toner base particles is coated with the aggregated particles of the present invention is used as a dry developer. Further, since the particle size distribution of the aggregated particles of the present invention is narrow and the shape of the aggregated particles is uniform, the toner surface coated with the aggregated particles of the present invention is used as a dry developer and a wet developer. Can be made uniform, and a toner with uniform chargeability can be obtained. Therefore, it has good fixability, storability and fixability, can make the charging property uniform, and can form a high-quality image more stably.

  Moreover, according to this invention, the glass transition temperature of resin is 40 to 70 degreeC, and the weight average molecular weight of resin is 10,000 or more and 300,000 or less. When the glass transition temperature of the resin is less than 40 ° C., the physical properties of the toner such as storage stability are remarkably lowered. When the glass transition temperature of the resin exceeds 70 ° C., the low-temperature fixability deteriorates. When the weight average molecular weight of the resin is less than 10,000, the mechanical strength of the toner image after fixing is lower than when the weight average molecular weight of the resin is 10,000 or more. For example, the formed image is recorded. There is a risk of missing images from the medium. When the weight average molecular weight of the resin exceeds 300,000, the low-temperature fixability is lowered. By using a resin whose glass transition temperature and weight average molecular weight are in the above-mentioned range, it is possible to improve toner physical properties such as storability, widen the fixable temperature range, and prevent image loss. A stable image can be formed more stably.

  According to the invention, the toner includes a release agent. When the toner contains a release agent, it is possible to improve the releasability between the fixing means and the recording medium in the fixing step and to improve the fixability as compared with the case where the toner does not contain the release agent. Therefore, the fixable temperature range can be greatly increased, and a high-quality image can be formed more stably.

  Further, according to the present invention, since the latent image is developed using the developer of the present invention, a high-definition and high-resolution toner image can be stably formed on the image carrier. Therefore, a high-quality image can be stably formed.

  Further, according to the present invention, an image carrier on which a latent image is formed, latent image forming means for forming a latent image on the image carrier, and a book capable of forming a high-definition and high-resolution toner image as described above. An image forming apparatus is realized with the developing device of the invention. By forming an image with such an image forming apparatus, a high-quality image can be stably formed.

1. Method for Producing Aggregated Particles The method for producing aggregated particles according to the first embodiment of the present invention includes a step of releasing a liquid medium containing a polymer dispersant and a treated product in a step of preparing a dispersion. Using a high-pressure machine, the treated product is atomized at a temperature higher by 100 ° C. or more and 150 ° C. or less than the flow tester outflow start temperature of the treated product to prepare a dispersion liquid in which the treated product fine particles are dispersed in a liquid medium. . By doing so, it is possible to prepare a dispersion in which fine particles having a particle size of submicron and a narrow particle size distribution are dispersed. Next, the fine particles in the dispersion prepared in the dispersion preparation step are aggregated. By including the polymer dispersant in the dispersion liquid, the fine particles can be aggregated little by little while maintaining appropriate dispersibility in the aggregation process as compared with the case where the dispersion liquid does not contain the polymer dispersant. Therefore, aggregated particles having a non-spherical shape, a narrow particle size distribution, and a single particle size (1 μm or more and less than 10 μm) can be stably produced.

  FIG. 1 is a flowchart showing the procedure of the method for producing aggregated particles according to the present embodiment. The method for producing aggregated particles according to the present embodiment includes a coarse powder preparation step t1, a slurry preparation step t2, a dispersion preparation step t3, and an aggregation step t4. In the coarse powder preparation step t1, the processed product is roughly pulverized to obtain a coarse powder of the processed product. In the slurry preparation step t2, the coarse powder of the processed product obtained in the coarse powder preparation step t1 and the liquid medium are mixed to prepare a coarse slurry. In the dispersion preparation step t3, the coarse powder of the processed product contained in the coarse powder slurry obtained in the slurry preparation step t2 is finely divided to prepare a dispersion in which the fine particles of the processed product are dispersed in the liquid medium. The dispersion liquid preparation step t3 includes a fine particle formation step t3a for forming the coarse powder contained in the coarse powder slurry, a cooling step t3b for cooling the dispersion obtained in the fine particle formation step t3a, and a dispersion obtained by the cooling step t3b. And a decompression step t3c for decompressing the liquid. In the aggregation step t4, the fine particles contained in the dispersion obtained in the dispersion preparation step t3 are aggregated so that the aggregated particles of the present invention are obtained.

(1) Coarse powder preparation step t1
In the coarse powder preparation step t1, the processed product is roughly pulverized to obtain a coarse powder of the processed product. The treated product can be used in an aqueous medium as long as it has a softening point that allows the particles of the treated product to be fused together. Specific examples include synthetic resins and waxes. When a synthetic resin is used as the processed product, for example, a melt-kneaded product containing only the synthetic resin, or a melt-kneaded product in which additives such as a colorant, a release agent, and a charge control agent are mixed with the synthetic resin is roughly pulverized, A coarse powder of the processed product is obtained.

  In the following description of the method for producing aggregated particles, a case is described in which a synthetic resin is used as a processed product and an additive such as a colorant, a release agent, and a charge control agent is included together with the synthetic resin.

  In order to obtain a melt-kneaded product, it is preferable to melt-knead additives such as a colorant, a release agent, and a charge control agent together with a synthetic resin that is a raw material for aggregated particles. The melt-kneaded material is, for example, powder-mixed with a synthetic resin and additives such as a colorant, a release agent, and a charge control agent, and then a temperature higher than the melting temperature of the synthetic resin, usually about 80 to 200 ° C., preferably It can manufacture by melt-kneading, heating at about 100-150 degreeC.

  Examples of the melt kneading include general kneaders such as a twin screw extruder, a three-roller, and a lab blast mill. More specifically, for example, a uniaxial or biaxial extruder such as TEM-100B (trade name, manufactured by Toshiba Machine Co., Ltd.) and PCM-65 / 87 (trade name, manufactured by Ikegai Co., Ltd.), and knee dicks. (Product name, manufactured by Mitsui Mining Co., Ltd.)

  The melt-kneaded product is cooled to become a solidified product. The cooled and solidified product of the melt-kneaded product is coarsely pulverized by a powder pulverizer such as a cutter mill, a feather mill, or a jet mill to obtain a synthetic resin coarse powder. The particle size of the coarse powder is not particularly limited, but is, for example, a particle size that can pass through the inlet of the high-pressure machine used in the micronization step t3 described later, preferably 450 μm or more and 1000 μm or less, more preferably about 500 μm to 800 μm. is there. Depending on the type of the kneader, the melt-kneaded product is cooled inside the kneader, and a melt-kneaded product having the above-mentioned preferred coarse particle size is obtained. Without being subjected to coarse pulverization, the slurry may be subjected to a slurry preparation step t2 described later.

(Synthetic resin)
Although it will not specifically limit as a synthetic resin if it is a thermoplastic resin, For example, a polyester resin, an acrylic resin, a polyurethane, and an epoxy resin can be used.

  Known polyesters can be used, and examples thereof include polycondensates of polybasic acids and polyhydric alcohols.

  As the polybasic acid, those known as polyester monomers can be used, for example, terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid and other aromatic carboxylic acids, maleic anhydride Examples thereof include aliphatic carboxylic acids such as acid, fumaric acid, succinic acid, alkenyl succinic anhydride, and adipic acid, and methyl esterified products of these polybasic acids. A polybasic acid can be used individually by 1 type, or can use 2 or more types together.

  As the polyhydric alcohol, those known as polyester monomers can be used. For example, aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, glycerin, cyclohexanediol, cyclohexanedimethanol And aromatic diols such as alicyclic polyhydric alcohols such as hydrogenated bisphenol A, ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, and the like. A polyhydric alcohol can be used individually by 1 type, or can use 2 or more types together.

  The polycondensation reaction between the polybasic acid and the polyhydric alcohol can be carried out according to a conventional method. For example, the polybasic acid and the polyhydric alcohol are contacted in the presence or absence of an organic solvent and in the presence of a polycondensation catalyst. The process is terminated when the acid value, softening point, etc. of the polyester to be produced reach a predetermined value. Thereby, polyester is obtained. When a methyl esterified product of a polybasic acid is used as a part of the polybasic acid, a demethanol polycondensation reaction is performed. In this polycondensation reaction, for example, the carboxyl group content at the end of the polyester can be adjusted by appropriately changing the mixing ratio of polybasic acid and polyhydric alcohol, the reaction rate, etc., and thus the properties of the resulting polyester are modified. it can. Further, when trimellitic anhydride is used as the polybasic acid, a modified polyester can be obtained also by easily introducing a carboxyl group into the main chain of the polyester.

  Although it does not restrict | limit especially as an acrylic resin, An acidic group containing acrylic resin can be used preferably. The acidic group-containing acrylic resin is, for example, an acrylic resin monomer or an acrylic resin monomer containing an acidic group or a hydrophilic group and / or a vinyl having an acidic group or a hydrophilic group when an acrylic resin monomer or an acrylic resin monomer and a vinyl monomer are polymerized. It can manufacture by using together a system monomer.

  Known acrylic resin monomers can be used, for example, acrylic acid that may have a substituent, methacrylic acid that may have a substituent, acrylic ester that may have a substituent, and a substituent. Methacrylic acid ester and the like. Acrylic resin monomers can be used alone or in combination of two or more.

  As the vinyl monomer, known monomers can be used, and examples thereof include styrene, α-methylstyrene, vinyl bromide, vinyl chloride, vinyl acetate, acrylonitrile and methacrylonitrile. A vinyl monomer can be used individually by 1 type, or can use 2 or more types together. The polymerization is performed by solution polymerization, suspension polymerization, emulsion polymerization, or the like using a general radical initiator.

  Although it does not restrict | limit especially as a polyurethane, For example, an acidic group or a basic group containing polyurethane can be used preferably. The acidic group or basic group-containing polyurethane can be produced according to a known method. For example, an acid group or basic group-containing diol, polyol and polyisocyanate may be subjected to addition polymerization. Examples of the acidic group or basic group-containing diol include dimethylolpropionic acid and N-methyldiethanolamine. Examples of the polyol include polyether polyols such as polyethylene glycol, polyester polyols, acrylic polyols, and polybutadiene polyols. Examples of the polyisocyanate include tolylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Each of these components can be used alone or in combination of two or more.

Although it does not restrict | limit especially as an epoxy resin, An acidic group or a basic group containing epoxy resin can be used preferably. An acidic group or basic group-containing epoxy resin is produced, for example, by adding or addition polymerizing a base epoxy resin with a polycarboxylic acid such as adipic acid and trimellitic anhydride or an amine such as dibutylamine or ethylenediamine. be able to.
Specific examples of additives such as a colorant, a release agent and a charge control agent will be described later.

(2) Slurry preparation process t2
In the slurry preparation step t2, the synthetic resin coarse powder (hereinafter referred to as “resin coarse powder”) obtained in the coarse powder preparation step t1 is mixed with the liquid medium, and the resin coarse powder is dispersed in the liquid medium. A slurry of resin coarse powder is prepared.

  Mixing of the resin coarse powder and the liquid medium is performed using a general mixer. As the mixer, for example, a PUC colloid mill (trade name, manufactured by Nippon Ball Valve Co., Ltd.), a grinding and atomizing machine T.I. K. Examples include Mycolloider (R) M type (trade name, manufactured by Primix Co., Ltd.) and Super Mas Colloider (trade name, manufactured by Masuko Sangyo Co., Ltd.).

  The liquid medium to be mixed with the resin coarse powder is not particularly limited as long as it is a liquid material that does not dissolve and uniformly disperse the resin coarse powder, but considering the ease of process management, waste liquid treatment after all processes, Water is preferred.

  The amount of the resin coarse powder added to the liquid medium is not particularly limited, but is preferably 3% by weight to 45% by weight, more preferably 5% by weight to 30% by weight of the total amount of the resin coarse powder and the liquid medium. is there. The mixing of the resin coarse powder and the liquid medium may be carried out under heating or cooling, but is usually carried out at room temperature.

(Polymer dispersant)
As the polymer dispersant, a polymer dispersant having an aggregating ability can be used. The polymer dispersant having coagulation ability has both dispersibility and coagulation ability, and functions as a dispersant in the slurry preparation step S2 and the dispersion preparation step S3 described later, and in the aggregation step S4 described later, a cationic system. By adding a dispersant or the like, the polymer dispersant is electrically neutralized, so that the dispersion stability of the polymer dispersant is lost and the fine particles are aggregated.

The polymer dispersant is preferably added to water before the resin coarse powder is added to water.
Examples of the polymer dispersant include acrylic monomers such as (meth) acrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, Β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2-acrylate Hydroxypropyl, hydroxyl group-containing acrylic monomers such as 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Ester monomers such as N-methylol acrylamide, vinyl alcohol monomers such as N-methylol methacrylamide, ethers with vinyl alcohol, vinyl alkyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether Monomers, vinyl alkyl ester monomers such as vinyl acetate, vinyl propionate and vinyl butyrate, aromatic vinyl monomers such as styrene, α-methylstyrene and vinyltoluene, acrylamide, methacrylamide and diacetone Acrylamide, amide monomers such as these methylol compounds, nitrile monomers such as acrylonitrile and methacrylonitrile, acid chloride monomers such as acrylic acid chloride and methacrylic acid chloride, vinyl pyridine, vinyl chloride One or two kinds selected from vinyl nitrogen-containing heterocyclic monomers such as redone, vinylimidazole, and ethyleneimine, and crosslinkable monomers such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, allyl methacrylate, and divinylbenzene. (Meth) acrylic polymers containing the following hydrophilic monomers, polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene Polyoxyethylene polymers such as nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester, etc. Cellulose polymers such as limer, methylcellulose, hydroxyethylcellulose, and hydroxypropylcellulose can be raised, but are not limited thereto.

  The polymer dispersant may be used in combination with other dispersants. Dispersants that can be used in combination include sodium polyoxyethylene lauryl phenyl ether sulfate, potassium polyoxyethylene lauryl phenyl ether sulfate, sodium polyoxyethylene nonyl phenyl ether sulfate, sodium polyoxyethylene oleyl phenyl ether sulfate, polyoxyethylene cetyl phenyl ether sulfate Sodium, polyoxyethylene lauryl phenyl ether ammonium sulfate, polyoxyethylene nonyl phenyl ether ammonium sulfate, polyoxyalkylene alkylaryl ether sulfate such as polyoxyethylene oleyl phenyl ether ammonium sulfate, polyoxyethylene lauryl ether sodium sulfate, polyoxyethylene lauryl ether sulfuric acid Potassium, polyoxyethylene olei Ether sulfate, polyoxyethylene cetyl ether sodium sulfate, polyoxyethylene lauryl ether sulfate, such as polyoxyalkylene alkyl ether sulfates such as polyoxyethylene oleyl ether ammonium sulfate but not limited thereto.

The addition amount of the dispersant including the dispersant to be used in combination is not particularly limited, but is preferably 0.05% by weight to 10% by weight, more preferably 0.1% by weight or more of the total amount of the liquid medium and the dispersant. 3% by weight or less.
In this way, a slurry containing resin coarse powder having a particle size of about 60 μm is obtained.

(3) Dispersion preparation step t3
In the dispersion preparation step t3, the liquid medium containing the polymer dispersant and the resin coarse powder, that is, the slurry of the resin coarse powder obtained in the slurry preparation step t2, is obtained using a high-pressure machine having a stepwise pressure release mechanism. The particle size distribution is narrow by preparing fine particles of resin coarse powder at a temperature 100 ° C. or more and 150 ° C. or less higher than the flow tester outflow start temperature of the coarse powder, and preparing a dispersion in which fine particles of the resin coarse powder are dispersed in the liquid medium. Agglomerated particles having a particle size of submicron are obtained. The dispersion preparation step t3 includes a micronization step t3a, a cooling step t3b, and a decompression step t3c.

(High pressure machine with gradual pressure release mechanism)
An example of a high-pressure machine having a stepwise pressure release mechanism is a high-pressure homogenizer. The high-pressure homogenizer is an apparatus that pulverizes particles such as resin coarse powder under pressure. In the present embodiment, a method for forming fine particles or granulating a synthetic resin or the like using a high-pressure homogenizer is referred to as a high-pressure homogenizer method.

  As the high-pressure homogenizer, commercially available products, those described in patent literature, and the like can be used. Commercially available high-pressure homogenizers include, for example, microfluidizer (trade name, manufactured by Microfluidics), nanomizer (trade name, manufactured by Nanomizer), and optimizer (trade name, manufactured by Sugino Machine Co., Ltd.). Chamber type high pressure homogenizer, high pressure homogenizer (trade name, manufactured by Rannie), high pressure homogenizer (trade name, manufactured by Sanmaru Kikai Kogyo Co., Ltd.), and high pressure homogenizer (trade name, manufactured by Izumi Food Machinery Co., Ltd.) Is mentioned. Examples of the high-pressure homogenizer described in the patent literature include those described in International Publication No. 03/059497 pamphlet. Among these, the high-pressure homogenizer described in International Publication No. 03/059497 is preferable.

  In the high-pressure homogenizer method using the high-pressure homogenizer described in the pamphlet of International Publication No. 03/059497, the micronization step t3a, the cooling step t3b, and the decompression step t3c can be performed.

  Below, it describes about the micronization process t3a, the cooling process t3b, and the pressure reduction process t3c in the case of using the high-pressure homogenizer described in the pamphlet of International Publication No. 03/059497.

(3) -1, micronization step t3a
In the micronization step t3a, the liquid medium containing the polymer dispersant and the resin coarse powder, that is, the resin coarse powder slurry obtained in the slurry preparation step t2, is used to start the flow of the resin coarse powder in a flow tester using a high-pressure homogenizer. Are processed at a temperature of 100 ° C. or higher and 150 ° C. or lower to make resin coarse powder fine particles. In order to make the resin coarse powder into fine particles, for example, a slurry of the resin coarse powder is passed through a pressure-resistant nozzle under heat and pressure.

  As the pressure-resistant nozzle, a general pressure-resistant nozzle capable of liquid flow can be used. For example, a multiple nozzle having a plurality of liquid flow paths can be preferably used. The liquid flow passages of the multiple nozzles may be formed concentrically around the axis of the multiple nozzle, or a plurality of liquid flow passages may be formed substantially parallel to the longitudinal direction of the multiple nozzles. As an example of the multiple nozzle used in the method for producing particles of the present embodiment, the inlet diameter and the outlet diameter are about 0.05 to 0.35 mm, and the length of the multiple nozzle is 0.5 to 5 cm. Examples include one or a plurality of liquid flow paths, preferably about 1-2.

The slurry of the resin coarse powder is introduced into the pressure-resistant nozzle from the inlet of the pressure-resistant nozzle, and the dispersion discharged from the outlet of the pressure-resistant nozzle has, for example, a micronized particle size of 0.3 to 1 μm and a submicron size. The particles are heated to a flow tester outflow start temperature of 100 ° C. or higher and 150 ° C. or lower and are pressurized to about 150 to 250 MPa.
One pressure-resistant nozzle may be provided, or a plurality of pressure-resistant nozzles may be provided.

(3) -2, cooling step t3b
In the cooling step t3b, the dispersion liquid containing fine particles (hereinafter also simply referred to as “fine particles”) of the resin coarse powder obtained in the micronization step t3a is heated and pressurized. Although the cooling temperature is not particularly limited, for example, the temperature of the dispersion is cooled to 30 ° C. or lower if one guideline is given. When the temperature of the dispersion is cooled to 30 ° C. or lower, the pressure applied to the dispersion is reduced to about 5 to 20 MPa.

  For cooling, a general liquid cooler having a pressure-resistant structure can be used, and among them, a cooler having a large cooling area such as a serpentine cooler is preferable. Further, it is preferable that the cooling gradient is reduced from the inlet of the cooler to the outlet of the cooler, that is, the cooling capacity is lowered. As a result, finer resin resin particles can be achieved more efficiently. Further, it is possible to prevent coarsening due to adhesion between fine particles of resin coarse powder, and to improve the yield of fine particles of resin coarse powder.

  The dispersion liquid containing the fine resin fine particles discharged from the pressure-resistant nozzle in the micronization step t3a is introduced into the cooler from, for example, the cooler inlet and is cooled inside the cooler having a cooling gradient. It is discharged from the exit. One or a plurality of coolers may be provided.

(3) -3, decompression step t3c
In the decompression step t3c, the pressure of the pressurized dispersion liquid containing fine particles of the resin coarse powder obtained in the cooling step t3b is reduced to a pressure at which bubbling does not occur, that is, bubbles do not occur. The dispersion liquid supplied from the cooling step t3b to the decompression step t3c is in a state of being pressurized to about 5 to 20 MPa. The pressure reduction is preferably performed gradually in steps.

  For this decompression operation, it is preferable to use a multistage decompression device described in WO 03/059497. The multistage pressure reducing device includes an inlet passage, an outlet passage, and a multistage pressure reducing means. The inlet passage introduces a dispersion liquid containing fine particles of resin coarse powder into the multistage decompression device. The outlet passage is formed so as to communicate with the inlet passage, and discharges the dispersion liquid containing fine particles of the reduced resin coarse powder to the outside of the multistage decompression device. The multistage pressure reducing means is provided between the inlet passage and the outlet passage, and two or more pressure reducing members are connected via a connecting member.

  Examples of the decompression member used for the multistage decompression means include a pipe-like member. An example of the connecting member is a ring-shaped seal. The multistage pressure reducing means is configured by connecting a plurality of pipe-shaped members having different inner diameters with a ring-shaped seal. For example, two to four pipe-like members having the same inner diameter are connected from the inlet passage to the outlet passage, and then one pipe-like member having an inner diameter approximately twice as large as these is connected. Dispersion liquid containing fine particles of resin coarse powder flowing through the pipe-shaped member by connecting about 1 to 3 small pipe-shaped members having an inner diameter of about 5 to 20% than the pipe-shaped member having a large inner diameter. Is gradually reduced to a pressure at which no bubbling occurs, preferably to atmospheric pressure.

  A heat exchanging means using a refrigerant or a heat medium may be provided around the multistage pressure reducing means, and cooling or heating may be performed according to the pressure value applied to the dispersion containing fine particles of resin coarse powder.

  The dispersion containing fine particles of the resin coarse powder obtained in the cooling step t3b is provided, for example, by providing a pressure resistant pipe between the cooling step t3b and the pressure reducing step t3c, and providing a supply pump and a supply valve on the pressure resistant pipe. The cooling process t3b is supplied to the decompression process t3c and introduced into the inlet passage of the multistage decompression device.

  The dispersion liquid containing resin particles having a reduced diameter reduced in the multistage depressurization apparatus is discharged from the outlet passage to the outside of the multistage depressurization apparatus.

One or more multistage pressure reducing devices may be provided.
In this way, a dispersion containing fine particles of resin coarse powder is obtained. In the present embodiment, the volume average particle diameter of the fine particles contained in the dispersion is preferably 0.05 μm or more and 0.50 μm or less. By producing particles by agglomerating fine particles having a volume average particle size of 0.05 μm or more and 0.50 μm or less, the shape difference between the particles is small, the shape is non-spherical, and the particle size distribution in the aggregation step t4 described later. Particles having a narrow single micron (1 μm or more and less than 10 μm) can be stably produced. If the volume average particle size of the fine particles is less than 0.05 μm, the smaller the fine particles in the liquid medium containing the polymer dispersant, the more stable and less aggregated. Compared with the case of the above, fine particles that do not aggregate are likely to remain, and the particle size distribution may not be narrowed. When the volume average particle diameter of the fine particles exceeds 0.50 μm, particles whose volume average particle diameter exceeds a single micron (1 μm or more and less than 10 μm) are compared with the case where the volume average particle diameter of the fine particles is 0.50 μm or less. Easy to manufacture.

Here, the volume average particle diameter of the fine particles is a value measured by a laser diffraction / scattering particle size measuring device (for example, Microtrack MT3000 manufactured by Nikkiso Co., Ltd.).

(4) Aggregation step t4
In the aggregation step t4, an aggregating agent is added to the dispersion obtained in the dispersion preparation step S3 to aggregate the fine particles, so that the shape is non-spherical, the particle size distribution is narrow, and the particle size is single micron (1 μm to 10 μm). Less than) agglomerated particles. Specifically, for example, particles having a small particle diameter among particles contained in the fine particles by the cohesive force of the polymer dispersant having an aggregating ability while adding an external force such as shear by adding the coagulant to the dispersion. In order to agglomerate the ultrafine particles and prevent the agglomeration from proceeding excessively, the generation of coarse particles that are particles having a large particle size among the particles contained in the fine particles is suppressed by an external force. The particle size distribution can be controlled from both the coarse particle side and the particle size distribution of the aggregated particles can be narrowed.

  The fine particles are aggregated by a granulator, for example. The granulating apparatus includes an agitating container to be accommodated, and an agitating means provided in the agitating container for agitating the fine particle dispersion, and the granulating apparatus can apply a shearing force from one mechanical direction. It is preferable to use an emulsifier or a disperser. Thereby, the particle diameter and shape of the formed aggregated particles can be made more uniform.

  Specific examples of the emulsifier and the disperser include, for example, Ultra Tarrax (trade name, manufactured by IKA Japan Co., Ltd.), Polytron homogenizer (trade name, manufactured by Kinematica Co., Ltd.), TK Auto Homo Mixer (trade name, manufactured by Primix Co., Ltd.). ), Max Blend (Sumitomo Heavy Industries, Ltd.) and other batch emulsifiers, Ebara Milder (trade name, manufactured by Ebara Corporation), TK Pipeline Homomixer (trade name, manufactured by Primix Corporation), TK Homomic Lineflow (trade name, manufactured by Primix Co., Ltd.), Fillmix (trade name, manufactured by Primix Co., Ltd.), colloid mill (trade name, manufactured by Shinko Pantech Co., Ltd.), Thrasher (trade name, manufactured by Mitsui Miike Chemical Industries, Ltd.) ), Trigonal wet pulverizer (trade name, manufactured by Mitsui Miike Chemical Co., Ltd.), Cabi Continuous emulsifiers such as Ron (trade name, manufactured by Eurotech Co., Ltd.), Fine Flow Mill (trade name, manufactured by Taiheiyo Kiko Co., Ltd.), Claremix (trade name, manufactured by M Technique Co., Ltd.), Fillmix (product) Name, manufactured by Primix Co., Ltd.).

  In mixing the dispersion and the flocculant, the stirring speed, stirring temperature, and stirring time of the granulating apparatus may be appropriately selected from values that provide aggregated particles having a desired particle size, particle size distribution, and shape. The shape of the aggregated particles is an external force, heat, time, and in this embodiment, the stirring speed (the number of revolutions of the granulator), the stirring temperature, and the stirring time are complicatedly entangled. Approaches a sphere and keeps a wrinkle-like shape if it is low, but even if the stirring temperature is high, if the stirring time is short and the stirring speed is slow, the shape of the aggregated particles becomes distorted. In addition, when the stirring time is long, the shape of the aggregated particles gradually approaches a sphere, but when the stirring temperature is low, the shape of the aggregated particles remains distorted no matter how long stirring is performed. The stirring time can be appropriately selected according to various conditions such as synthetic resin, binder resin, colorant, other toner additive components, flocculant and dispersant, and concentration contained in the processed product. it can.

  As described above, the polymer dispersant also has an aggregating ability, and in the aggregation step S4, the polymer dispersant is electrically neutralized by adding an aggregating agent such as a cationic dispersant. The dispersion stability of the molecular dispersant is lost, and the fine particles are aggregated. The polymer dispersant has a long chain in the molecule, and the polymer dispersant itself is considered to be dispersed in the dispersion by bridging the fine particles. Innumerable functional groups in the molecule, for example, polyacrylic acid, can neutralize the carboxyl group with the agglomerated salt contained in the aggregating agent and finely adjust the degree of invalidation, that is, destabilization. Accordingly, since the fine particles can be gradually aggregated while maintaining appropriate dispersibility, aggregated particles having a narrow particle size distribution and a non-spherical shape can be produced.

(Flocculant)
As the aggregating agent, for example, a cationic dispersant, a polyvalent metal salt, or the like can be used. Examples of the cationic dispersant include, for example, alkyltrimethylammonium type cationic dispersants, alkylamidoamine type cationic dispersants, alkyldimethylbenzylammonium type cationic dispersants, cationized polysaccharide type cationic dispersants, and alkylbetaine type cationic dispersants. Dispersants, alkylamide betaine type cationic dispersants, sulfobetaine type cationic dispersants, amine oxide type cationic dispersants, metal salts and the like are preferable. Examples of the metal salt include chlorides such as sodium, potassium, calcium, and magnesium, and sulfates.

  In addition, the polyvalent metal salt used as the flocculant is a divalent or higher metal salt. The divalent or higher metal is preferably an alkaline earth metal such as magnesium, calcium or barium, a Group 13 element of the periodic table such as aluminum, and particularly preferably magnesium or aluminum. Specific examples of the divalent or higher metal salt include magnesium sulfate, aluminum sulfate, barium chloride, magnesium chloride, calcium chloride, aluminum chloride, aluminum hydroxide, and magnesium hydroxide.

  Among the above-mentioned flocculants, sodium chloride is preferable because of its relatively high solubility in water and a slow flocculation rate. The amount of the flocculant used is preferably 0.5 to 20 parts by weight, more preferably 0.5 to 18 parts by weight, particularly preferably 100 parts by weight of the fine particle dispersion. 1.0 to 18 parts by weight. If the amount is less than 0.5 part by weight, the agglomeration effect may be insufficient. If the amount exceeds 20 parts by weight, the agglomerated particles may become too large due to overaggregation.

  In this way, an aqueous dispersion containing aggregated particles is obtained. In the present embodiment, the particle diameter of the aggregated particles is preferably 4 to 40 times the particle diameter of the fine particles contained in the dispersion containing fine resin coarse particles. If the particle size of the aggregated particles is less than 4 times the particle size of the fine particles contained in the dispersion containing the fine resin particles, the fine particles contained in the dispersion containing the fine resin particles Compared to a case where the particle diameter is 4 times or more, there is a possibility that aggregated particles having a large shape difference and a wide particle size distribution are produced. If the particle diameter of the aggregated particles exceeds 40 times the particle diameter of the fine particles contained in the dispersion containing fine resin coarse particles, aggregated particles having a shape close to a sphere may be produced. The particle size of the aggregated particles is 4 to 40 times the particle size of the fine particles contained in the dispersion containing fine particles of the resin coarse powder, so that there is little shape difference between the particles, the shape is non-spherical, Single-micron (1 μm or more and less than 10 μm) particles having a narrow distribution can be produced more stably.

  In the above-described method for producing aggregated particles, the process from t1 to t4 may be performed only once, or after the process from t1 to t4 is performed once, the process from t3 to t4 may be performed repeatedly. Good.

2. Aggregated particles The aggregated particles according to the second embodiment of the present invention are obtained by the method for producing aggregated particles of the present invention. The agglomerated particles produced by the method for producing agglomerated particles of the present invention have a non-spherical shape, a narrow particle size distribution, and a particle size of a single micron (1 μm or more and less than 10 μm). For example, when applied to the electrophotographic field, a developer with uniform performance can be obtained.

  The aggregated particles of the present embodiment are non-spherical particles having a volume average particle diameter of 3 μm or less and a volume particle size distribution variation coefficient CV represented by the following formula (1) of 25% or less.

Coefficient of variation CV (%) = (standard deviation / volume average particle diameter) × 100 (1)
In the present embodiment, non-spherical particles are particles having a shape factor SF1 of 130 to 140 and a shape factor SF2 of 120 to 130.

  In the present embodiment, the shape factor SF1 indicating the roundness of the particles and the shape factor SF2 indicating the unevenness of the particles are values measured according to the following method.

  In a 100 ml beaker, 2.0 g of particles, 1 ml of sodium alkyl ether sulfate and 50 ml of pure water were added and stirred well to prepare a particle dispersion. This particle dispersion was treated with an ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho Co., Ltd.) at an output of 50 μA for 5 minutes and further dispersed. After standing for 6 hours and removing the supernatant, 50 ml of pure water was added and stirred for 5 minutes with a magnetic stirrer, followed by suction filtration using a membrane filter (diameter 1 μm). The washed product on the membrane filter was vacuum-dried in a desiccator containing silica gel for about overnight.

A metal film (Au film, film thickness 0.5 μm) was formed on the surfaces of the particles whose surfaces had been cleaned in this way by sputtering deposition. From this metal film-coated particle, 200 to 300 particles were randomly extracted at an acceleration voltage of 5 kV and a magnification of 1000 times with a scanning electron microscope (trade name: S-570, manufactured by Hitachi, Ltd.). I took a photo. The electron micrograph data is subjected to image analysis with image analysis software (trade name: A image-kun, manufactured by Asahi Kasei Engineering Co., Ltd.). Particle analysis parameters of the image analysis software “A image-kun” are: small figure removal area: 100 pixels, shrinkage separation: number of times 1; small figure: 1; number of times: 10, noise removal filter: none, shading: none, result display unit : Μm. The shape factors SF1 and SF2 are obtained by the following formulas (A) and (B) from the maximum particle length MXLNG, the perimeter length PERI, and the graphic area AREA.
SF1 = {(MXLNG) 2 / AREA} × (100π / 4) (A)
SF2 = {(PERI) 2 / AREA} × (100 / 4π) (B)

  The shape factor SF1 is a value represented by the above formula (A), and indicates the degree of roundness of the shape of the particles. When the value of SF1 is 100, the shape of the particle is a true sphere, and becomes larger as the value of SF1 increases. The shape factor SF2 is a value represented by the above formula (B), and indicates the degree of unevenness of the surface shape of the particles. When the value of SF2 is 100, unevenness does not exist on the particle surface, and the larger the value of SF2, the more prominent the unevenness.

  When the obtained agglomerated particles are used as a powder, the agglomerated particles are dried by solid-liquid separation by general separation means such as filtration and centrifugation.

  In the present embodiment, it is preferable that the aforementioned processed product includes at least a synthetic resin. When the treated product contains at least a synthetic resin, the shape is non-spherical, the particle size distribution is narrow, the particle size is single micron (1 μm or more and less than 10 μm), and aggregated particles containing at least the synthetic resin can be produced. . The aggregated particles can be used as a toner in the electrophotographic field, for example. Further, the aggregated particles can be used as a shell material for capsule particles, thereby greatly expanding the design range of the core material. In the case of manufacturing a capsule structure, the material to be the core material and the particles of the present invention forming the shell layer are used. The substance used as the core material is not particularly limited.

  In the present embodiment, it is preferable that the aforementioned processed product includes at least a colorant. The agglomerated particles produced by the method for producing agglomerated particles of the present invention have a non-spherical shape, a narrow particle size distribution, and a particle size of a single micron (1 μm or more and less than 10 μm). By including, it is possible to produce agglomerated particles having a non-spherical shape, a narrow particle size distribution, a particle size of single micron (1 μm or more and less than 10 μm), and containing at least a colorant. The aggregated particles can be suitably used as, for example, a wet toner.

3. Toner The agglomerated particles of the present invention produced as described above can be used as dry and wet toners as they are, for example, or can be further agglomerated to a desired size and used as dry toner.

  The toner according to the third embodiment of the present invention includes at least the aggregated particles of the present invention. The aggregated particles of the present invention are non-spherical particles having a volume average particle diameter of 3 μm or less and a volume particle size distribution variation coefficient CV of 25% or less. Non-spherical particles are particles having SF1 of 130 to 140 and SF2 of 120 to 130. SF1 indicates the degree of roundness of the particles. SF2 indicates the degree of unevenness of the particles. In general, the smaller the toner particle size, the more difficult the transfer residual toner on the image carrier is removed by the cleaning blade, so the cleaning performance decreases. The tendency for the cleaning property to decrease as the particle diameter of the toner decreases becomes more prominent as the particle shape of the toner becomes spherical and the unevenness of the particle surface decreases. If the SF1 is less than 130, the shape of the aggregated particles contained in the toner is too round, which may deteriorate the cleaning property. When SF1 exceeds 140, the contact area between the image carrier and the intermediate transfer medium and the toner is larger than when SF1 is 140 or less, and the adhesion between the image carrier and the intermediate transfer medium and the toner is increased. Since it becomes large, the toner becomes difficult to be transferred to the recording medium, and there is a possibility that the transferability is lowered. Further, compared with the case where the shape factor SF1 is 140 or less, the shape of the aggregated particles becomes indefinite, and the aggregated particles have corners. Therefore, if the toner includes the aggregated particles of the present invention, the developer is developed in the developing tank. Aggregated particles rub against each other during idling of the agent, and the agglomerated particles are cracked, whereby fine particles of the agglomerated particles are generated and the particle size distribution may be broadened. If the SF2 is less than 120, the unevenness of the aggregated particle surface is too small and the cleaning property may be deteriorated. When SF2 exceeds 130, the transferability may be lowered, and when the developer is idling, fine particles of the aggregated particles are likely to be generated due to cracking of the aggregated particles, which may lead to a broad particle size distribution.

  When the toner contains the aggregated particles of the present invention, a toner having a single peak, a narrow particle size distribution, a non-spherical shape, and a particle size of single micron (1 μm or more and less than 10 μm) can be realized. When an image is formed with such a toner, image loss due to poor cleaning can be prevented and transferability can be improved in both dry and wet processes, so that a high-quality image can be stably formed. be able to. Further, in the dry process, the toner particles are easily collected by the filter in the image forming apparatus and the toner particles can be prevented from floating, and thus can be used without adversely affecting the human body.

A method for further aggregating the agglomerated particles according to the second embodiment of the present invention to produce the toner according to the third embodiment of the present invention is not particularly limited. For example, the method described in the aggregating step t4 described above is used. Similarly to the method, the aggregated particles according to the second embodiment of the present invention can be aggregated to produce the toner according to the third embodiment of the present invention.

In order to obtain a melt-kneaded product, it is preferable to melt-knead additives such as a synthetic resin, a colorant, a release agent, and a charge control agent, which are raw materials for aggregated particles. The melt-kneaded material is, for example, powder-mixed with a synthetic resin, a colorant, a release agent, a charge control agent, and the like, and then a temperature equal to or higher than the melting temperature of the synthetic resin, usually about 80 to 200 ° C., preferably 100 to 150. It can be produced by melt-kneading while heating to about ° C.

(Binder resin)
The toner of the present embodiment includes at least a binder resin and a colorant. The binder resin is not particularly limited as long as it is a thermoplastic resin, and the synthetic resin described in (synthetic resin) in the above-described coarse powder preparation step t1 can be used. Resins, polyurethanes, epoxy resins and the like can be suitably used. Among these resins, polyester resins, acrylic resins, and epoxy resins are more preferable. Since these resins are excellent in transparency and can impart good powder fluidity, low-temperature fixability, secondary color reproducibility and the like to the obtained toner particles, they are suitable as binder resins for color toners. Furthermore, what grafted polyester resin and acrylic resin can also be used suitably.

  In consideration of easy granulation operation, kneadability with a colorant and uniform shape and size of the toner particles obtained, a binder resin having a softening point of 150 ° C. or lower is preferable. A binder resin having a temperature of from 150 ° C. to 150 ° C. is particularly preferable. Among such binder resins, the glass transition temperature of the binder resin is preferably 40 ° C. or higher and 70 ° C. or lower, and the weight average molecular weight of the binder resin is preferably 10,000 or higher and 300,000 or lower. When the glass transition temperature of the binder resin is less than 40 ° C., the physical properties of the toner such as storage stability are remarkably lowered. When the glass transition temperature of the binder resin exceeds 70 ° C., the low-temperature fixability deteriorates. When the weight average molecular weight of the binder resin is less than 10,000, the mechanical strength of the toner image after fixing is lower than that when the weight average molecular weight of the binder resin is 10,000 or more. There is a risk of missing images from the recording medium. When the weight average molecular weight of the binder resin exceeds 300,000, the low-temperature fixability is lowered. By using a binder resin having a glass transition temperature and a weight average molecular weight within the above-mentioned range, it is possible to improve toner physical properties such as storage stability, widen the fixable temperature range, and prevent image loss. A high-quality image can be formed more stably.

  Binder resins can be used alone or in combination of two or more different types. Furthermore, even if it is the same resin, what differs in any or all of molecular weight, a monomer composition, etc. can use multiple types.

(Coloring agent)
Examples of the colorant include a yellow toner colorant, a magenta toner colorant, and a cyan toner colorant.

  Examples of the colorant for yellow toner include C.I. I. Pigment yellow 1, C.I. I. Pigment yellow 5, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 15 and C.I. I. Pigment yellow 17 pigment yellow 180, C.I. I. Organic pigments such as CI Pigment Yellow 93, Pigment Yellow 74, and Pigment Yellow 185; inorganic pigments such as yellow iron oxide and ocher; I. Nitro dyes such as Acid Yellow 1, C.I. I. Solvent Yellow 2, C.I. I. Solvent Yellow 6, C.I. I. Solvent Yellow 14, C.I. I. Solvent Yellow 15, C.I. I. Solvent Yellow 19, and C.I. I. Examples thereof include oil-soluble dyes such as Solvent Yellow 21.

  Examples of the colorant for magenta toner include C.I. I. Pigment red 49, C.I. I. Pigment red 57, C.I. I. Pigment red 81, C.I. I. Pigment red 122, C.I. I. Solvent Red 19, C.I. I. Solvent Red 49, C.I. I. Solvent Red 52, C.I. I. Basic Red 10 and C.I. I. Disperse Red 15 etc. are mentioned.

  Examples of the colorant for cyan toner include C.I. I. Pigment blue 15, C.I. I. Pigment blue 16, C.I. I. Solvent Blue 55, C.I. I. Solvent Blue 70, C.I. I. Direct Blue 25, and C.I. I. Direct Blue 86 and the like can be mentioned.

  In addition to these pigments, red pigments and green pigments can be used. A coloring agent can be used individually by 1 type, or can use 2 or more types together. Two or more of the same color can be used, and one or more of the different colors can also be used.

  The colorant is preferably used as a masterbatch. A master batch of a colorant can be produced, for example, by kneading a synthetic resin melt and a colorant. As the synthetic resin, the same kind of resin as the toner binder resin or a resin having good compatibility with the toner binder resin is used. The use ratio of the synthetic resin and the colorant is not particularly limited, but is preferably 30 parts by weight or more and 100 parts by weight or less with respect to 100 parts by weight of the synthetic resin. The master batch is used after being granulated to have a particle diameter of about 2 to 3 mm, for example.

  The content of the colorant in the toner is not particularly limited, but is preferably 2 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the binder resin. When using a masterbatch, it is preferable to adjust the usage amount of the masterbatch so that the content of the colorant in the toner of the present invention falls within the above range. By using the colorant in the above-mentioned range, it is possible to form a good image having a sufficient image density, high color developability and excellent image quality.

(Release agent)
In the present embodiment, the toner preferably contains a release agent. When the toner contains a release agent, it is possible to improve the releasability between the fixing means and the recording medium in the fixing step and to improve the fixability as compared with the case where the toner does not contain the release agent. Therefore, the fixable temperature range can be greatly increased, and a high-quality image can be formed more stably.

  The release agent used in the present invention is not particularly limited, and publicly known waxes such as paraffin wax and derivatives thereof, and microcrystalline wax and derivatives thereof can be used. Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof, low molecular weight polypropylene wax and derivatives thereof, and hydrocarbon synthetic waxes such as polyolefin polymer wax and derivatives thereof, carnauba wax and derivatives thereof, ester waxes, and the like Can be mentioned. The amount of the release agent used is not particularly limited and can be appropriately selected from a wide range, but is preferably 0.2 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the binder resin. If the release agent is contained in an amount of more than 20 parts by weight, filming on the photoconductor and spent on the carrier may easily occur. If the release agent is less than 0.2 parts by weight, the function of the release agent may be increased. There is a risk that it may not be fully utilized.

  Although the melting point of the release agent is not particularly limited, if the melting point is too high, there is no effect in improving the fixing property, that is, improving the release property, and if the melting point is too low, the storage property is deteriorated. The melting point of is preferably 30 ° C. or higher and 120 ° C. or lower.

(Charge control agent)
In the present embodiment, the toner may contain a charge control agent. As the charge control agent, a charge control agent for positive charge control or negative charge control can be used. For example, positive dyes such as nigrosine dyes, basic dyes, quaternary ammonium salts, quaternary phosphonium salts, aminopyrines, pyrimidine compounds, polynuclear polyamino compounds, aminosilanes, nigrosine dyes and derivatives thereof, triphenylmethane derivatives, guanidine salts, and amidine salts. Charge control agents for charge control and, for example, oil-soluble dyes such as oil black and spiron black, metal-containing azo compounds, azo complex dyes, metal salts of naphthenic acid, metal complexes and metal salts of salicylic acid and its derivatives (metal is Chromium, zinc, zirconium, etc.), boron compounds, fatty acid soaps, long-chain alkyl carboxylates, and charge control agents for controlling negative charges such as resin acid soaps. One charge control agent can be used alone, or two or more charge control agents can be used in combination. The amount of the compatible charge control agent used is preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the binder resin, more preferably 0.5 to 100 parts by weight of the binder resin. It is not less than 3 parts by weight. If the charge control agent is contained in an amount of more than 5 parts by weight, the carrier is contaminated, toner scattering occurs, and if the content of the incompatible charge control agent is less than 0.5 parts by weight, Sufficient charging characteristics cannot be imparted.

  In the present embodiment, the toner preferably covers the surface of the toner base particles with the aggregated particles of the second embodiment of the present invention. As the toner base particles, the aggregated particles of the second embodiment of the present invention may be used, or particles that can be used as other toners may be used. By covering the surface of the toner base particles with the aggregated particles according to the second embodiment of the present invention, when the toner base particles contain a release agent, problems caused by including the release agent can be suppressed. It can be a toner having good fixability, storage stability and durability, and exhibits a remarkable effect particularly when a toner in which the surface of toner base particles is coated with the aggregated particles of the present invention is used as a dry developer. Can do. Further, since the particle size distribution of the aggregated particles of the present invention is narrow and the shape of the aggregated particles is uniform, the toner surface coated with the aggregated particles of the present invention is used as a dry developer and a wet developer. Can be made uniform, and a toner with uniform chargeability can be obtained. Therefore, it has good fixability, storability and fixability, can make the charging property uniform, and can form a high-quality image more stably.

(1) Dry toner When the toner of the present embodiment is used as a dry toner, powder flowability improvement, triboelectric chargeability improvement, heat resistance, long-term storage stability improvement, cleaning property improvement, photoreceptor surface wear property control, etc. An external additive having the above function may be externally added to the toner.

(External additive)
As the external additive, those commonly used in this field can be used, and examples thereof include fine silica powder, fine titanium oxide powder and fine alumina powder. These inorganic fine powders are used for the purpose of hydrophobization, chargeability control, etc., silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups and other organics. It is preferably treated with a treating agent such as a silicon compound. The said processing agent can be used individually by 1 type, or can use 2 or more types together.

  The external additive is added in an amount of 1 part by weight with respect to 100 parts by weight of the toner in consideration of the charge amount necessary for the toner, the influence on the abrasion of the photosensitive member by adding the external additive and the environmental characteristics of the toner. The amount is preferably 10 parts by weight or less and more preferably 5 parts by weight or less.

  The external additive preferably has a number average particle diameter of primary particles of 10 nm to 500 nm. By using an external additive having such a particle size, the effect of improving the fluidity of the toner is more easily exhibited.

(2) Wet toner When used as a wet toner, for example, a wet toner dispersion in which the toner of the present invention (preferably a toner having a volume average particle diameter of 1 μm to 3 μm) is dispersed in an insulating liquid is prepared. . The method for preparing the wet toner dispersion is not particularly limited, and can be prepared by a general method.

(Insulating liquid)
As the insulating liquid used in the present invention, known ones can be used, for example, liquid n-paraffinic hydrocarbons, iso-paraffinic hydrocarbons, or mixtures thereof, alicyclic hydrocarbons, aromatic hydrocarbons, Examples thereof include halogenated aliphatic hydrocarbons and silicone oils. Among these, it is preferable to use silicone oil. By using the silicone oil, it functions as a release agent when fixing the toner particles to the recording medium, so that the occurrence of offset can be effectively prevented, that is, the offset resistance is improved.

  Silicone oil has a polysiloxane skeleton and is composed of a polymer represented by the general formula:-[O-SiR1 (R2)] n-, where R1 and R2 are a methyl group, a phenyl group, or hydrogen. Certain straight silicone oils, reactive modified silicone oils having amino groups, epoxy groups, carboxyl groups, carbinol groups, methacrylic groups, mercapto groups, phenol groups, etc. in at least one of the side chain and terminal, and polyether groups, methylstyryl Group, alkyl group, higher fatty acid ester group, hydrophilic special group, higher fatty acid group, non-reactive modified silicone oil having fluorine or the like in at least one of its side chain and terminal, etc., one or two of these A combination of the above can be used. Among these, it is more preferable to use a non-reactive modified polysiloxane (non-reactive modified silicone) as a main component. When the non-reactive modified polysiloxane is a main component, the thermal stability of the silicone oil is higher, so that a wet developer having more stable characteristics can be obtained.

  In the preparation of the wet toner dispersion, a dispersant soluble in the insulating liquid, for example, a surfactant may be used. By using a dispersant that is soluble in the insulating liquid, the dispersibility of the wet toner of the present invention in the insulating liquid can be improved.

  The content of the wet toner of the present invention in the wet toner dispersion is not particularly limited, but is preferably 1 wt% or more and 30 wt% or less, and more preferably 5 wt% or more and 20 wt% or less.

  In addition to the above, the wet toner dispersion may contain components such as a charge control agent and magnetic powder. Examples of the charge control agent include benzoic acid metal salt, salicylic acid metal salt, alkyl salicylic acid metal salt, catechol metal salt, metal-containing bisazo dye, nigrosine dye, tetraphenylborate derivative, quaternary ammonium salt, alkyl Examples include pyridinium salts, chlorinated polyesters, and nitrohumic acids. Examples of the magnetic powder include magnetite, maghemite, various ferrites, cupric oxide, nickel oxide, zinc oxide, zirconium oxide, titanium oxide, magnesium oxide, and other metal oxides such as Fe, Co, and Ni. The thing comprised with the magnetic material containing a magnetic metal etc. are mentioned.

  In addition to the above materials, for example, zinc stearate, zinc oxide, cerium oxide, or the like may be added to the dispersion.

4. Developer The developer according to the fourth embodiment of the present invention includes the toner according to the third embodiment of the present invention. When the developer contains the toner according to the third embodiment of the present invention, a developer with uniform performance can be obtained.

(1) Dry developer As described above, a dry toner in which an external additive is externally added to the toner particles as necessary can be used as it is as a one-component developer, or can be mixed with a carrier to form a two-component. It can be used as a developer.

  When used as a one-component developer, the toner is used only without using a carrier. When used as a one-component developer, a blade and a fur brush are used, the toner is triboelectrically charged with a developing sleeve, and the toner is transported by adhering the toner onto the sleeve to form an image.

  When used as a two-component developer, the toner of the present invention is used with a carrier. As the carrier, known ones can be used. For example, single or composite ferrite composed of iron, copper, zinc, nickel, cobalt, manganese, chromium, etc. is used as carrier core particles, and the surface of the carrier core particles is coated with a coating substance. Examples thereof include a resin-coated carrier or a resin-dispersed carrier in which magnetic particles are dispersed in a resin.

  As the coating material of the resin-coated carrier, known materials can be used, for example, polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, metal compound of ditertiary butyl salicylic acid, styrene Resins, acrylic resins, polyacids, polyvinyllarls, nigrosine, aminoacrylate resins, basic dyes, basic dye lakes, fine silica powders, fine alumina powders, and the like.

  Although it does not restrict | limit especially as resin used for a resin dispersion type carrier, For example, a styrene acrylic resin, a polyester resin, a fluorine resin, a phenol resin, etc. are mentioned. The resin used for the coating material of the resin-coated carrier and the resin-dispersed carrier is preferably selected according to the toner component, and one kind can be used alone or two or more kinds can be used in combination.

The shape of the carrier is preferably a spherical shape or a flat shape.
Although the particle diameter of the carrier is not particularly limited, it is preferably 10 μm or more and 100 μm or less, and more preferably 20 μm or more and 50 μm or less, considering high image quality.

The volume resistivity of the carrier is preferably 10 ⁸ Ω · cm or more, and more preferably 10 ¹² Ω · cm or more. The volume resistivity of the carrier is determined by placing the carrier in a container having a cross-sectional area of 0.50 cm ² and tapping it, then applying a load of 1 kg / cm ² by the weight packed in the container, It is a value obtained by reading a current value when a voltage that generates an electric field of 1000 V / cm is applied during the period. When the resistivity of the carrier is low, when a bias voltage is applied to the developing sleeve, charges are injected into the carrier, and carrier particles are likely to adhere to the photoreceptor. Further, breakdown of the bias voltage is likely to occur.

  The magnetization strength (maximum magnetization) of the carrier is preferably 10 emu / g or more and 60 emu / g or less, more preferably 15 emu / g or more and 40 emu / g or less. The magnetization strength depends on the magnetic flux density of the developing roller, but under the general magnetic flux density conditions of the developing roller, if it is less than 10 emu / g, the magnetic binding force does not work and causes carrier scattering. There is a fear. On the other hand, if the magnetization strength exceeds 60 emu / g, it is difficult to maintain a non-contact state with the image carrier in the non-contact development in which the carrier spikes are too high. Further, in the contact development, there is a risk that a sweep is likely to appear in the toner image.

The use ratio of the dry toner and the carrier in the two-component developer is not particularly limited and can be appropriately selected according to the type of the dry toner and the carrier, but an example is a resin-coated carrier (density 5 to 8 g / cm ² ). The dry toner may be used so that the dry toner is contained in the developer in an amount of 2 to 30% by weight, preferably 2 to 20% by weight, based on the total amount of the developer. In the two-component developer, the carrier coverage with dry toner is preferably 40 to 80%.

(2) Wet developer The wet toner dispersion in which the above-described wet toner is dispersed in an insulating liquid can be used as it is as a wet developer.

5. Image forming apparatus An image forming apparatus according to the fifth embodiment of the present invention uses the developer according to the fourth embodiment of the present invention.

(1) Dry Process Image Forming Apparatus The dry developer can be used, for example, in the dry process image forming apparatus shown in FIG. FIG. 2 is a schematic cross-sectional view schematically showing the configuration of the dry process image forming apparatus 1 according to the fifth embodiment of the present invention. The dry process image forming apparatus 1 is a multifunction machine having both a copying function, a printer function, and a facsimile function, and forms a full-color or monochrome image on a recording material in accordance with transmitted image information. That is, the dry-process image forming apparatus 1 has three types of printing modes, ie, a copier mode (copying mode), a printer mode, and a FAX mode, and an operation input from an operation unit (not shown), a personal computer, and a portable terminal device The print mode is selected by the control unit (to be described later) in response to reception of a print job from an external device using the information recording storage medium or the memory device.

  The dry process image forming apparatus 1 includes a toner image forming unit 2, a transfer unit 3, a fixing unit 4, a recording material supply unit 5, and a discharge unit 6. Each member constituting the toner image forming unit 2 and some members included in the transfer unit 3 are black (b), cyan (c), magenta (m), and yellow (y) colors included in the color image information. In order to correspond to the image information, four each are provided. Here, each member provided by four according to each color is distinguished by attaching an alphabet representing each color to the end of the reference symbol, and when referring collectively, only the reference symbol is used.

  The toner image forming unit 2 includes a photosensitive drum 11, a charging unit 12, an exposure unit 13, a developing device 14, and a cleaning unit 15. The charging unit 12, the developing device 14, and the cleaning unit 15 are arranged around the photosensitive drum 11 in this order. The charging unit 12 is disposed below the developing device 14 and the cleaning unit 15 in the vertical direction. The charging unit 12 and the exposure unit 13 correspond to a latent image forming unit.

  The photosensitive drum 11 serving as an image carrier is supported by a driving unit (not shown) so as to be rotatable around an axis, and includes a conductive substrate (not shown) and a photosensitive layer formed on the surface of the conductive substrate. The conductive substrate can take various shapes, and examples thereof include a cylindrical shape, a columnar shape, and a thin film sheet shape. Among these, a cylindrical shape is preferable. The conductive substrate is formed of a conductive material. As the conductive material, those commonly used in this field can be used. For example, metals such as aluminum, copper, brass, zinc, nickel, stainless steel, chromium, molybdenum, vanadium, indium, titanium, gold, platinum, and the like. A conductive layer made of one or more of aluminum, aluminum alloy, tin oxide, gold, indium oxide and the like is formed on a film-like substrate such as two or more alloys, synthetic resin film, metal film or paper. And a resin composition containing conductive particles and / or a conductive polymer. As the film-like substrate used for the conductive film, a synthetic resin film is preferable, and a polyester film is particularly preferable. As a method for forming the conductive layer in the conductive film, vapor deposition, coating, and the like are preferable.

  The photosensitive layer is formed, for example, by laminating a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material. It is preferable to provide an undercoat layer between the conductive substrate and the charge generation layer or the charge transport layer. By providing an undercoat layer, the scratches and irregularities present on the surface of the conductive substrate are coated to smooth the surface of the photosensitive layer, to prevent deterioration of the chargeability of the photosensitive layer during repeated use. Alternatively, an advantage of improving the charging characteristics of the photosensitive layer in a low humidity environment can be obtained. Further, a laminated photoreceptor having a three-layer structure having a high durability and having a photoreceptor surface protective layer as the uppermost layer may be used.

  The charge generation layer is mainly composed of a charge generation material that generates a charge upon irradiation with light, and contains a known binder resin, plasticizer, sensitizer, and the like as necessary. As the charge generation material, those commonly used in this field can be used. Phthalocyanine pigments such as metal-free phthalocyanine, squalium dye, azulenium dye, thiapyrylium dye, carbazole skeleton, styryl stilbene skeleton, triphenylamine skeleton, dibenzothiophene skeleton, oxadiazole skeleton, fluorenone skeleton, bis stilbene skeleton, distyryl oxa And azo pigments having a diazole skeleton or a distyrylcarbazole skeleton. Among these, metal-free phthalocyanine pigments, oxotitanyl phthalocyanine pigments, bisazo pigments containing a fluorene ring and / or a fluorenone ring, bisazo pigments composed of aromatic amines, trisazo pigments, etc. have high charge generation ability and high sensitivity. Suitable for obtaining a photosensitive layer. One type of charge generating material can be used alone, or two or more types can be used in combination. Although the content of the charge generation material is not particularly limited, it is preferably 5 parts by weight or more and 500 parts by weight or less, more preferably 10 parts by weight or more and 200 parts by weight or less with respect to 100 parts by weight of the binder resin in the charge generation layer. is there.

  As the binder resin for the charge generation layer, those commonly used in this field can be used. For example, melamine resin, epoxy resin, silicone resin, polyurethane, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, polycarbonate, phenoxy resin , Polyvinyl butyral, polyarylate, polyamide and polyester. Binder resin can be used individually by 1 type, or can use 2 or more types together as needed.

  The charge generation layer generates charge by dissolving or dispersing appropriate amounts of charge generation materials, binder resins and, if necessary, plasticizers and sensitizers in an appropriate organic solvent capable of dissolving or dispersing these components. It can be formed by preparing a layer coating solution, applying this charge generation layer coating solution to the surface of the conductive substrate, and drying. The film thickness of the charge generation layer thus obtained is not particularly limited, but is preferably 0.05 μm or more and 5 μm or less, more preferably 0.1 μm or more and 2.5 μm or less.

  The charge transport layer laminated on the charge generation layer has a charge transport material having the ability to accept and transport the charge generated from the charge generation material and a binder resin for the charge transport layer as essential components. Contains known antioxidants, plasticizers, sensitizers, lubricants and the like. As the charge transport material, those commonly used in this field can be used, for example, poly-N-vinylcarbazole and derivatives thereof, poly-γ-carbazolylethyl glutamate and derivatives thereof, pyrene-formaldehyde condensation product and derivatives thereof, Polyvinylpyrene, polyvinylphenanthrene, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, 9- (p-diethylaminostyryl) anthracene, 1,1-bis (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, pyrazoline Derivatives, phenylhydrazones, hydrazone derivatives, triphenylamine compounds, tetraphenyldiamine compounds, triphenylmethane compounds, stilbene compounds, 3-methyl-2-benzothiazoline -Donating substances such as azine compounds, fluorenone derivatives, dibenzothiophene derivatives, indenothiophene derivatives, phenanthrenequinone derivatives, indenopyridine derivatives, thioxanthone derivatives, benzo [c] cinnoline derivatives, phenazine oxide derivatives, tetracyano And electron accepting substances such as ethylene, tetracyanoquinodimethane, promanyl, chloranil and benzoquinone. The charge transport materials can be used alone or in combination of two or more. Although the content of the charge transport material is not particularly limited, it is preferably 10 parts by weight or more and 300 parts by weight or less, more preferably 30 parts by weight or more and 150 parts by weight or less with respect to 100 parts by weight of the binder resin in the charge transport material. .

  As the binder resin for the charge transport layer, those commonly used in this field and capable of uniformly dispersing the charge transport material can be used. For example, polycarbonate, polyarylate, polyvinyl butyral, polyamide, polyester, polyketone, epoxy resin, polyurethane , Polyvinyl ketone, polystyrene, polyacrylamide, phenol resin, phenoxy resin, polysulfone resin, and copolymer resins thereof. Among these, in consideration of film formability, wear resistance of the resulting charge transport layer, electrical characteristics, etc., polycarbonate containing bisphenol Z as a monomer component (hereinafter referred to as “bisphenol Z type polycarbonate”), bisphenol Z type polycarbonate And a mixture of polycarbonate with other polycarbonates are preferred. Binder resin can be used individually by 1 type, or can use 2 or more types together.

  The charge transport layer preferably contains an antioxidant together with the charge transport material and the binder resin for the charge transport layer. As antioxidants, those commonly used in this field can be used, such as vitamin E, hydroquinone, hindered amine, hindered phenol, paraphenylenediamine, arylalkanes and their derivatives, organic sulfur compounds, and organic phosphorus compounds. Can be mentioned. One antioxidant can be used alone, or two or more antioxidants can be used in combination. The content of the antioxidant is not particularly limited, but is 0.01% by weight or more and 10% by weight or less, preferably 0.05% by weight or more and 5% by weight or less of the total amount of components constituting the charge transport layer.

  The charge transport layer is dissolved or dispersed in a suitable organic solvent that can dissolve or disperse these components in an appropriate amount such as a charge transport material and a binder resin, and if necessary, an antioxidant, a plasticizer, and a sensitizer. The charge transport layer coating solution is prepared, and the charge transport layer coating solution is applied to the surface of the charge generation layer and dried. The film thickness of the charge transport layer thus obtained is not particularly limited, but is preferably 10 to 50 μm, more preferably 15 to 40 μm.

  Note that a photosensitive layer in which a charge generation material and a charge transport material are present can be formed in one layer. In that case, the type, content, binder resin, and other additives of the charge generation material and the charge transport material may be the same as in the case of separately forming the charge generation layer and the charge transport layer.

  In this embodiment, the photosensitive drum formed by forming the organic photosensitive layer using the charge generation material and the charge transport material as described above is used. Instead, an inorganic photosensitive layer using silicon or the like is formed. Can be used.

  The charging unit 12 faces the photosensitive drum 11 and is arranged so as to be separated from the surface of the photosensitive drum 11 along the longitudinal direction of the photosensitive drum 11 with a gap, and the surface of the photosensitive drum 11 has a predetermined polarity and Charge to potential. As the charging unit 12, for example, a charging brush type charger, a charger type charger, a saw-tooth type charger, an ion generator, or the like can be used. In the present embodiment, the charging unit 12 is provided so as to be separated from the surface of the photosensitive drum 11, but is not limited thereto. For example, a charging roller may be used as the charging unit 12, and the charging roller may be arranged so that the charging roller and the photosensitive drum are in pressure contact with each other, or a contact charging type charger such as a charging brush or a magnetic brush may be used. .

  The exposure unit 13 is arranged such that light of each color information emitted from the exposure unit 13 passes between the charging unit 12 and the developing device 14 and is irradiated on the surface of the photosensitive drum 11. The exposure unit 13 branches the image information into light of each color information of black, cyan, magenta, and yellow in the unit, and the surface of the photosensitive drum 11 charged to a uniform potential by the charging unit 12 is light of each color information. To form an electrostatic latent image on the surface. As the exposure unit 13, for example, a laser scanning unit including a laser irradiation unit and a plurality of reflecting mirrors can be used. In addition, a unit in which an LED array, a liquid crystal shutter, and a light source are appropriately combined may be used.

  The developing device 14 includes a developing tank 20 and a toner hopper 21. The developing tank 20 is disposed so as to face the surface of the photosensitive drum 11, and is a container that supplies toner to the electrostatic latent image formed on the surface of the photosensitive drum 11 and develops it to form a visible toner image. It is a shaped member. The developing tank 20 accommodates toner in its internal space, and accommodates a roller member such as the developing roller 110, the supply roller 111, and the agitation roller 112 or a screw member and rotatably supports the developing tank. An opening 114 is formed on a side surface of the developing tank 20 facing the photosensitive drum 11, and the developing roller 110 is rotatably provided at a position facing the photosensitive drum 11 through the opening 114.

  The developing roller 110 is a roller-like member that supplies toner to the electrostatic latent image on the surface of the photoconductor 11 at the pressure contact portion or the closest portion with the photoconductor drum 11. When supplying the toner, a potential having a polarity opposite to the charging potential of the toner is applied to the surface of the developing roller 110 as a developing bias voltage (hereinafter simply referred to as “developing bias”). As a result, the toner on the surface of the developing roller 110 is smoothly supplied to the electrostatic latent image. Further, by changing the development bias value, the toner adhesion amount, that is, the toner amount supplied to the electrostatic latent image can be controlled.

  The supply roller 111 is a roller-like member provided to face the developing roller 110 so as to be rotationally driven, and supplies toner to the periphery of the developing roller 110. The agitating roller 112 is a roller-like member provided so as to be able to rotate and face the supply roller 111, and supplies the toner newly supplied from the toner hopper 21 into the developing tank 20 to the periphery of the supply roller 111.

  The toner hopper 21 is provided so that a toner replenishing port (not shown) provided at the lower part in the vertical direction and a toner receiving port (not shown) provided at the upper part in the vertical direction of the developing tank 20 communicate with each other. Supply toner accordingly. Further, the toner hopper 21 may not be used, and the toner may be directly supplied from each color toner cartridge.

  The cleaning unit 15 removes the toner remaining on the surface of the photosensitive drum 11 after transferring the toner image to the recording material, and cleans the surface of the photosensitive drum 11. For the cleaning unit 15, for example, a plate-like member such as a cleaning blade is used. In the image forming apparatus 1 of the present invention, an organic photosensitive drum is mainly used as the photosensitive drum 11, and the surface of the organic photosensitive drum is mainly composed of a resin component. Surface degradation is likely to proceed due to the chemical action of ozone. However, the deteriorated surface portion is worn by receiving a rubbing action by the cleaning unit 15 and is gradually but surely removed. Therefore, the problem of surface deterioration due to ozone or the like is practically solved, and the charging potential by the charging operation can be stably maintained over a long period of time. Although the cleaning unit 15 is provided in this embodiment, the present invention is not limited to this, and the cleaning unit 15 may not be provided.

  According to the toner image forming unit 2, the surface of the photosensitive drum 11 that is uniformly charged by the charging unit 12 is irradiated with signal light corresponding to the image information from the exposure unit 13 to form an electrostatic latent image. Toner is supplied from the developing device 14 to form a toner image. After the toner image is transferred to the intermediate transfer belt 25, the toner remaining on the surface of the photosensitive drum 11 is removed by the cleaning unit 15. This series of toner image forming operations is repeatedly executed.

  The transfer unit 3 is disposed above the photosensitive drum 11 and includes an intermediate transfer belt 25, a driving roller 26, a driven roller 27, an intermediate transfer roller 28, a transfer belt cleaning unit 29, and a transfer roller 30.

  The intermediate transfer belt 25 is an endless belt-like member that is stretched by a driving roller 26 and a driven roller 27 to form a loop-shaped movement path, and is driven to rotate in the direction of an arrow B. When the intermediate transfer belt 25 passes through the photosensitive drum 11 while being in contact with the photosensitive drum 11, an intermediate transfer roller 28 disposed on the surface of the photosensitive drum 11 is opposed to the photosensitive drum 11 via the intermediate transfer belt 25. A transfer bias having a polarity opposite to the charging polarity of the toner is applied, and the toner image formed on the surface of the photosensitive drum 11 is transferred onto the intermediate transfer belt 25. In the case of a full-color image, each color toner image formed on each photoconductor drum 11 is sequentially transferred onto the intermediate transfer belt 25 to form a full-color toner image.

  The driving roller 26 is provided so as to be rotatable around its axis by driving means (not shown), and the intermediate transfer belt 25 is driven to rotate in the direction of arrow B by the rotational driving. The driven roller 27 is provided so as to be able to be driven and rotated by the rotational drive of the driving roller 26, and applies a certain tension to the intermediate transfer belt 25 so that the intermediate transfer belt 25 does not loosen. The intermediate transfer roller 28 is provided in pressure contact with the photosensitive drum 11 via the intermediate transfer belt 25 and capable of being driven to rotate about its axis by a driving unit (not shown). The intermediate transfer roller 28 is connected to a power source (not shown) for applying a transfer bias as described above, and has a function of transferring the toner image on the surface of the photosensitive drum 11 to the intermediate transfer belt 25.

  The transfer belt cleaning unit 29 is provided so as to face the driven roller 27 through the intermediate transfer belt 25 and to contact the outer peripheral surface of the intermediate transfer belt 25. Since the toner adhering to the intermediate transfer belt 25 due to contact with the photosensitive drum 11 causes the back surface of the recording material to be contaminated, the transfer belt cleaning unit 29 removes and collects the toner on the surface of the intermediate transfer belt 25.

  The transfer roller 30 is provided in pressure contact with the drive roller 26 via the intermediate transfer belt 25, and can be driven to rotate about an axis by a drive unit (not shown). At the pressure contact portion between the transfer roller 30 and the driving roller 26, that is, the transfer nip portion, the toner image carried and conveyed by the intermediate transfer belt 25 is transferred to the recording material fed from the recording material supply means 5 described later. The The recording material carrying the toner image is fed to the fixing unit 4.

  According to the transfer unit 3, the toner image transferred from the photosensitive drum 11 to the intermediate transfer belt 25 at the pressure contact portion between the photosensitive drum 11 and the intermediate transfer roller 28 rotates the intermediate transfer belt 25 in the arrow B direction. It is conveyed to the transfer nip portion by driving, and transferred to the recording material there.

  The fixing unit 4 is provided downstream of the transfer unit 3 in the recording material conveyance direction, and includes a fixing roller 31 and a pressure roller 32. The fixing roller 31 is rotatably provided by a driving unit (not shown), and heats and melts the toner constituting the unfixed toner image carried on the recording material to fix it on the recording material. A heating unit (not shown) is provided inside the fixing roller 31. The heating unit heats the fixing roller 31 so that the surface of the fixing roller 31 reaches a predetermined temperature (heating temperature). For example, a heater or a halogen lamp can be used as the heating means. The heating means is controlled by fixing condition control means described later. The control of the heating temperature by the fixing condition control means will be described in detail later. A temperature detection sensor is provided near the surface of the fixing roller 31 to detect the surface temperature of the fixing roller 31. The detection result by the temperature detection sensor is written in the storage unit of the control means described later.

  The pressure roller 32 is provided so as to be in pressure contact with the fixing roller 31 and is supported so as to be driven to rotate by the rotation drive of the pressure roller 32. The pressure roller 32 assists fixing of the toner image on the recording material by pressing the toner and the recording material when the toner is melted and fixed on the recording material by the fixing roller 31. A pressure contact portion between the fixing roller 31 and the pressure roller 32 is a fixing nip portion.

  According to the fixing unit 4, the recording material onto which the toner image has been transferred by the transfer unit 3 is sandwiched between the fixing roller 31 and the pressure roller 32, and the toner image is recorded under heating when passing through the fixing nip portion. By being pressed against the material, the toner image is fixed on the recording material, and an image is formed.

  The recording material supply unit 5 includes an automatic paper feed tray 35, a pickup roller 36, a transport roller 37, a registration roller 38, and a manual paper feed tray 39. The automatic paper feed tray 35 is a container-like member that is provided in the lower part of the image forming apparatus 1 in the vertical direction and stores a recording material. Recording materials include plain paper, color copy paper, overhead projector sheets, postcards, and the like. The pickup roller 36 takes out the recording material stored in the automatic paper feed tray 35 one by one and feeds it to the paper transport path S1. The conveyance rollers 37 are a pair of roller members provided so as to be in pressure contact with each other, and convey the recording material toward the registration rollers 38. The registration rollers 38 are a pair of roller members provided so as to be in pressure contact with each other, and the recording material fed from the conveyance roller 37 is used for conveying the toner image carried on the intermediate transfer belt 25 to the transfer nip portion. Synchronously, it is fed to the transfer nip. The manual paper feed tray 39 is a device that takes recording material into the image forming apparatus 1 by manual operation. The recording material taken from the manual paper feed tray 39 passes through the paper conveyance path S2 by the conveyance roller 37. Then, it is fed to the registration roller 38. According to the recording material supply means 5, the toner image carried on the intermediate transfer belt 25 is conveyed to the transfer nip portion by the recording material supplied one by one from the automatic paper feed tray 35 or the manual paper feed tray 39. In synchronism with this, the sheet is fed to the transfer nip portion.

  The discharge unit 6 includes a conveyance roller 37, a discharge roller 40, and a discharge tray 41. The conveyance roller 37 is provided on the downstream side of the fixing nip portion in the sheet conveyance direction, and conveys the recording material on which the image is fixed by the fixing unit 4 toward the discharge roller 40. The discharge roller 40 discharges the recording material on which the image is fixed to a discharge tray 41 provided on the upper surface in the vertical direction of the image forming apparatus 1 in the dry process. The discharge tray 41 stores the recording material on which the image is fixed.

  The dry-process image forming apparatus 1 includes a control unit (not shown). The control means is provided, for example, in the upper part of the internal space of the image forming apparatus 1 for a dry process, and includes a storage unit, a calculation unit, and a control unit. The storage unit of the control means includes various set values via an operation panel (not shown) arranged on the upper surface of the dry process image forming apparatus 1, sensors (not shown) arranged at various locations inside the dry process image forming apparatus 1, and the like. Detection result, image information from an external device, and the like are input. In addition, programs for executing various means are written. Examples of the various means include a recording material determination means, an adhesion amount control means, and a fixing condition control means. As the storage unit, those commonly used in this field can be used, and examples thereof include a read only memory (ROM), a random access memory (RAM), and a hard disk drive (HDD).

  As the external device, an electrical / electronic device capable of forming or obtaining image information and electrically connected to an image forming apparatus of a dry process can be used. For example, a computer, a digital camera, a television, a video recorder, Examples include DVD recorders, HDDVDs, Blu-ray disc recorders, facsimile machines, and portable terminal devices.

  The calculation unit takes out various data written in the storage unit, that is, an image formation command, a detection result, image information, and a program of various means, and performs various determinations. The control unit sends a control signal to the corresponding device according to the determination result of the calculation unit, and performs operation control. The control unit and the calculation unit include a processing circuit realized by a microcomputer, a microprocessor, or the like that includes a central processing unit (CPU). The control means includes a main power supply together with the processing circuit described above, and the power supply supplies power not only to the control means but also to each device in the image forming apparatus of the dry process.

(2) Wet Process Image Forming Apparatus The wet toner containing aggregated particles according to the second embodiment of the present invention can be used in, for example, the wet process image forming apparatus 201 shown in FIG. FIG. 3 is a schematic cross-sectional view schematically showing the configuration of the wet-process image forming apparatus 201 according to the fifth embodiment of the present invention. The image forming apparatus 201 includes a photosensitive drum 211, a charging device 212, a toner image forming unit 202, a developing device 214, a transfer device 203, and a cleaning roller 215. The photosensitive drum 211 corresponds to an image carrier.

  Around the photosensitive drum 211, a toner image forming unit 202, a developing device 214, a transfer device 203, and a cleaning roller 215 are arranged in this order. As indicated by an arrow 211a, the photosensitive drum 211 can be rotated clockwise by a driving mechanism (not shown). By this rotation operation, the image carrying surface of the surface of the photosensitive drum 211 carrying the electrostatic latent image or the toner image is relatively to the cleaning roller 215, the toner image forming unit 202, the developing device 214, the transfer device 203, and the like. Moving.

  Photosensitive drum 211 includes a base having a conductive surface and a photosensitive layer formed on the conductive surface. The photosensitive layer contains, for example, a material that changes in a charged state or the like by light irradiation, for example, an amorphous silicon photosensitive material. This photoreceptor layer is charged to a positive polarity by a charging device 212 described later. The photoreceptor layer can be covered with a release layer (not shown).

  The toner image forming unit 202 includes a static elimination device (not shown), a charging device 212, and a writing device 213.

  The static eliminator uniformly eliminates the portion of the photosensitive layer of the photosensitive drum 211 that is located in front of the static eliminator. That is, the static eliminator erases the electrostatic latent image from the photoreceptor layer after the transfer process.

  The charging device 212 is, for example, a corona charger represented by a corotron charger and a scorotron charger. The charging device 212 uniformly charges a portion of the photoconductor layer of the photoconductor drum 211 positioned in front of the charging device 212 to positive polarity.

  The writing device 213 includes a light source such as a laser exposure device or an LED and an optical system that guides light emitted from the light source to a photosensitive layer. The writing device 213 irradiates the photoconductor layer with light corresponding to the image information, and neutralizes the light irradiation portion of the photoconductor layer. As a result, an electrostatic latent image composed of an irradiated portion that is a low potential portion and a non-irradiated portion that is a high potential portion can be obtained.

  The developing device 214 supplies the wet toner of the present invention to the image bearing surface of the photosensitive drum 211. The developing device 214 includes, for example, a container 220 that stores wet toner, a developing roller 210 that is rotatably arranged with a slight gap from the image carrying surface, and a rotating roller that rotates the developing roller 210 counterclockwise in the drawing. And a voltage applying mechanism (not shown) for applying a voltage to the developing roller 210.

  By rotating the developing roller 210 counterclockwise in the drawing, a toner layer made of wet toner can be formed between the developing roller 210 and the photosensitive drum 211. At this time, the potential of the developing roller 210 is set to a potential between the surface potential at the irradiated portion of the photosensitive drum 211 and the surface potential at the non-irradiated portion. By doing so, in the toner layer formed between the developing roller 210 and the photosensitive drum 211, the positively charged toner particles move toward the light irradiation portion of the photosensitive layer. As a result, a toner image is formed on the image bearing surface of the photosensitive drum 211 with a pattern corresponding to the electrostatic latent image.

  The transfer device 203 includes an intermediate transfer roller 226 and a backup roller 230. The transfer device 203 transfers the toner image on the surface of the photosensitive drum 211 to the recording medium 235 via the intermediate transfer roller 226. The transfer device 203 uses a pressure generated by pressing the photosensitive drum 211 and the intermediate transfer roller 226 to transfer the toner image from the photosensitive drum 211 to the intermediate transfer roller 226. To transfer a toner image from the intermediate transfer roller 226 to a recording medium 235 such as a sheet and an OHP sheet, pressure generated by pressing the intermediate transfer roller 226 and the backup roller 230 is used.

  The intermediate transfer roller 226 is pressed against the photosensitive drum 211 so that the transfer surface is in contact with the image carrying surface of the photosensitive drum 211. The intermediate transfer roller 226 rotates in the direction of the arrow 226 as the photosensitive drum 211 rotates.

  The backup roller 230 is pressed against the intermediate transfer roller 226 so that its pressure surface is in contact with the transfer surface of the intermediate transfer roller 226 via the recording medium 235. The backup roller 230 rotates in the direction of the arrow 230 a as the intermediate transfer roller 226 rotates.

  The transfer device 203 may further include a heater. That is, the transfer device 203 may be configured such that pressure and heat can be used for transferring the toner image from the photosensitive drum 211 to the intermediate transfer roller 226 and transferring the toner image from the intermediate transfer roller 226 to the recording medium 235235. Good. Further, the transfer device 203 may include a transport mechanism that moves the recording medium 235 in the direction of the arrow 235a.

The intermediate transfer roller 226 may be an intermediate transfer belt.
The cleaning roller 215 removes toner remaining on the image bearing surface after transfer.

  As described above, since the developing devices 14 and 214 develop the electrostatic latent image using the developer according to the fourth embodiment of the present invention, high-definition and high-resolution toner on the photosensitive drums 11 and 211. An image can be formed stably. Therefore, a high-quality image can be stably formed.

  As described above, in the image forming apparatuses 1 and 201 according to the fifth and fifth embodiments of the present invention, the photosensitive drums 11 and 211 on which the electrostatic latent images are formed and the photosensitive drums 11 and 211 are electrostatically connected. The image forming apparatus 1 includes a toner image forming unit 2 202 for forming a latent image, and developing devices 14 and 214 capable of forming high-definition and high-resolution toner images on the photosensitive drums 11 and 211 as described above. , 201 is realized. By forming an image with such an image forming apparatus, a high-quality image can be stably formed.

Each physical property in Examples and Comparative Examples was measured as follows.
[Volume average particle diameter of fine particles and aggregated particles, and coefficient of variation CV of fine particles and aggregated particles]
Measurement was performed using a laser diffraction / scattering particle size distribution measuring apparatus (trade name: Microtrack MT3000, manufactured by Nikkiso Co., Ltd.). In order to prevent aggregation of the measurement sample (fine particles and aggregated particles), a dispersion liquid in which the measurement sample (fine particles and aggregated particles) is dispersed in an aqueous solution of Family Fresh (manufactured by Kao Corporation) and stirred. Injection was performed twice and the average was obtained. The measurement conditions were: measurement time: 30 seconds, particle refractive index: 1.4, particle shape: non-spherical, solvent: water, solvent refractive index: 1.33. Measure the volume particle size distribution of the measurement sample (fine particles or agglomerated particles), and calculate from the measurement results the particle size at which the cumulative volume from the small particle size side in the cumulative volume distribution is 50% as the volume average particle size (μm) of the particles did. Further, the standard deviation (μm) in the volume particle size distribution was obtained, and the coefficient of variation CV (%) was calculated based on the following formula (1). The coefficient of variation means that the smaller the value, the narrower the particle size distribution width.
Coefficient of variation CV (%) = {(standard deviation of volume particle size distribution) / (volume average particle diameter)} × 100
... (1)

[Shape Factor SF1 and Shape Factor SF2 of Aggregated Particles]
To a 100 ml beaker, 2.0 g of aggregated particles, 1 ml of sodium alkyl ether sulfate and 50 ml of pure water were added and stirred well to prepare a dispersion of aggregated particles. This dispersion was treated with an ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho Co., Ltd.) at an output of 50 μA for 5 minutes and further dispersed. After standing for 6 hours and removing the supernatant, 50 ml of pure water was added, and the mixture was stirred with a magnetic stirrer for 5 minutes, and then subjected to suction filtration using a membrane filter (caliber: 1 μm). The washed product on the membrane filter was vacuum-dried in a desiccator containing silica gel for about overnight.

A metal film (Au film, film thickness 0.5 μm) was formed on the surface of the agglomerated particles whose surface had been cleaned in this manner by sputtering deposition. About 500 of these metal film-coated aggregated particles were randomly extracted with a scanning electron microscope (trade name: S-570, manufactured by Hitachi, Ltd.) at an acceleration voltage of 5 kV and at a magnification of 1000 times. I took a photo. The electron micrograph data was subjected to image analysis with image analysis software (trade name: A image-kun, manufactured by Asahi Kasei Engineering Co., Ltd.). The analysis parameters of the image analysis software “A image-kun” are: small figure removal area: 100 pixels, shrinkage separation: number of times 1; small figure: 1; number of times: 10, noise removal filter: none, shading: none, result display unit: μm. The shape factor SF1 and the shape factor SF2 were obtained from the maximum length MXLNG, the perimeter length PERI, and the graphic area AREA of the agglomerated particles thus obtained by the following equations (2) and (3).
SF1 = {(MXLNG) 2 / AREA} × (100π / 4) (2)
SF2 = {(PERI) 2 / AREA} × (100 / 4π) (3)

[Glass transition point of binder resin (Tg)]
In accordance with Japanese Industrial Standard (JIS) K7121-1987, a differential scanning calorimeter (trade name: DSC220, manufactured by Seiko Denshi Kogyo Co., Ltd.) was used to heat 1 g of a sample at a heating rate of 10 ° C. per minute to obtain a DSC curve. It was measured. Draw the endothermic peak corresponding to the glass transition of the obtained DSC curve at a point where the slope is maximum with respect to the straight line that extends the base line on the high temperature side to the low temperature side and the curve from the rising part of the peak to the vertex. The temperature at the intersection with the tangent was determined as the glass transition point (Tg).

[Binder resin flow tester outflow start temperature (Ti)]
In a flow characteristic evaluation apparatus (trade name: Flow Tester CFT-100C, manufactured by Shimadzu Corporation), a load of 10 kgf / cm ² (9.8 × 10 ⁵ Pa) was applied to produce 1 g of binder resin (nozzle diameter 1 mm, Set to be extruded from a length of 1 mm), heated at a heating rate of 6 ° C. per minute, obtained the temperature when the molten binder resin started to come out of the die hole, and started outflow of the binder resin to the flow tester The temperature (Ti) was set.

[Molecular weight Mw of binder resin]
Using a GPC apparatus (trade name: HLC-8220 GPC, manufactured by Tosoh Corporation), at a temperature of 40 ° C., a 0.25 wt% tetrahydrofuran (hereinafter referred to as THF) solution of the sample was used as the sample solution, and the sample solution was injected. The molecular weight distribution curve was determined with an amount of 200 μL. The molecular weight at the peak of the obtained molecular weight distribution curve was determined as the peak top molecular weight. Moreover, the weight average molecular weight Mw was calculated | required from the obtained molecular weight distribution curve. The molecular weight calibration curve was prepared using standard polystyrene.

[Melting point of release agent]
Using a differential scanning calorimeter (trade name: DSC220, manufactured by Seiko Denshi Kogyo Co., Ltd.), 1 g of the release agent was heated from a temperature of 20 ° C. to 200 ° C. at a heating rate of 10 ° C. per minute, and then from 200 ° C. to 20 ° C. The DSC curve was measured by repeating the rapid cooling operation twice. The temperature at the top of the endothermic peak corresponding to the melting of the DSC curve measured in the second operation was determined as the melting point of the release agent.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. In the following examples and comparative examples, the flow tester outflow start temperature is simply referred to as outflow start temperature (Ti).

Example 1
[Coarse powder preparation step t1]
Polyester (binder resin, glass transition point (Tg) 58 ° C., outflow start temperature (Ti) 87 ° C., Mw = 77000) 81.8 parts by weight, masterbatch (containing CI Pigment Red 122) 12% Parts by weight, paraffin wax (release agent, trade name: HNP11, Nippon Seiki Co., Ltd., melting point 68 ° C.) 4.2 parts by weight, and alkyl salicylic acid metal salt (charge control agent, trade name: BONTRON E-84, (Orient Chemical Co., Ltd.) 1.5 parts by weight was mixed with a Henschel mixer for 10 minutes, and then melt-kneaded using a twin-screw extrusion kneader (trade name: PCM65, Ikegai Co., Ltd.) Obtained.

[Slurry preparation step t2]
900 parts by weight of the melt-kneaded product obtained in the coarse powder preparation step t1, 90 parts by weight of a dispersant (trade name: New Coal 10N, manufactured by Nippon Emulsifier Co., Ltd.), a wetting agent (trade name: Air Roll, Toho Chemical Industries, Ltd.) 2 parts by weight) and 2008 parts by weight of ion-exchanged water were added to a PUC colloid mill (trade name, manufactured by Nippon Ball Valve Co., Ltd.), and wet pulverized to obtain a melt-kneaded slurry.

[Particulate formation step t3a, cooling step t3b, decompression step t3c]
Next, using a high-pressure homogenizer nano3000, the melt-kneaded product contained in the melt-kneaded product slurry was microparticulated under the following micronization conditions, cooled, and decompressed to obtain a dispersion in which the melt-kneaded product fine particles were dispersed. .

<Mineralization conditions>
Pressure 210Mpa
Set temperature 200 ℃
Nozzle diameter 0.07mm

[Aggregating step t4]
12 parts by weight of a flocculant (primary sodium chloride, manufactured by Wako Pure Chemical Industries, Ltd.) is added to 600 parts by weight of the dispersion in which the fine particles of the melt-kneaded product obtained in the micronization step t3a are dispersed, and Claremix W motion is used. Then, an aqueous dispersion of particles was prepared by aggregating fine particles contained in a dispersion in which fine particles of the melt-kneaded material were dispersed under the following aggregation conditions.

<Aggregating conditions>
Set temperature 62 ℃
Rotation speed (rotor / stator) 18000rpm / 16200rpm
Set temperature holding time 10 minutes

The aqueous dispersion of aggregated particles obtained as described above was thoroughly washed with ion-exchanged water and then dried to obtain aggregated particles. The aggregated particles were used as the toner of Example 1. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 1.34 Coefficient of variation (%) 21

(Example 2)
In the micronization step t3a, the setting temperature was changed from 200 ° C. to 188 ° C., and in the aggregation step t4, the addition amount of the flocculant was changed from 12 parts by weight to 9 parts by weight. A toner of Example 2 was obtained. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 1.93 Coefficient of variation (%) 24

(Example 3)
Performed in the same manner as in Example 1 except that the setting temperature was changed from 200 ° C. to 235 ° C. in the micronization step t3a and the addition amount of the flocculant was changed from 12 parts by weight to 11 parts by weight in the aggregation step t4. The toner of Example 3 was obtained. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 2.01 Coefficient of variation (%) 22

Example 4
In the micronization step t3a, the addition amount of the dispersant (trade name: New Coal 10N, manufactured by Nippon Emulsifier Co., Ltd.) was changed from 90 parts by weight to 45 parts by weight, and the addition amount of ion exchange water was changed from 2008 parts by weight to 2053 parts by weight. The toner of Example 4 was obtained in the same manner as in Example 1 except that the amount of the toner was changed. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 1.98 Coefficient of variation (%) 31

(Example 5)
In the micronization step t3a, the addition amount of the dispersant (trade name: New Coal 10N, manufactured by Nippon Emulsifier Co., Ltd.) was changed from 90 parts by weight to 180 parts by weight, and the addition amount of ion exchange water was changed from 2008 parts by weight to 1918 parts by weight. The toner of Example 5 was obtained in the same manner as in Example 1 except that the amount of the toner was changed. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 1.63 Coefficient of variation (%) 42

(Example 6)
As a binder resin, instead of the polyeltel used in Example 1, the glass transition point (Tg) is 53 ° C., the outflow start temperature (Ti) is 80 ° C., and the weight average molecular weight (Mw) is 48000. A toner of Example 6 was obtained in the same manner as in Example 1 except that a certain polyester was used. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 2.03 Coefficient of variation (%) 23

(Example 7)
As a binder resin, instead of the polyeltel used in Example 1, the glass transition point (Tg) is 55 ° C., the outflow start temperature (Ti) is 84 ° C., and the weight average molecular weight (Mw) is 52000. A toner of Example 7 was obtained in the same manner as in Example 1 except that a certain polyester was used and the addition amount of the flocculant was changed from 12 parts by weight to 13 parts by weight in the aggregation step t4. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 1.29 Coefficient of variation (%) 20

(Example 8)
As the binder resin, instead of the polyeltel used in Example 1, the glass transition point (Tg) is 65 ° C., the outflow start temperature (Ti) is 96 ° C., and the weight average molecular weight (Mw) is 190000. Example 1 except that a polyester was used, the setting temperature was changed from 200 ° C. to 245 ° C. in the micronization step t3a, and the addition amount of the flocculant was changed from 12 parts by weight to 10 parts by weight in the aggregation step t4. In the same manner, a toner of Example 8 was obtained. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 2.27 Coefficient of variation (%) 23

Example 9
As the binder resin, instead of the polyeltel used in Example 1, the glass transition point (Tg) is 66 ° C., the outflow start temperature (Ti) is 98 ° C., and the weight average molecular weight (Mw) is 203000. Example 1 except that a polyester was used, the setting temperature was changed from 200 ° C. to 245 ° C. in the micronization step t3a, and the addition amount of the flocculant was changed from 12 parts by weight to 10 parts by weight in the aggregation step t4. The toner of Example 9 was obtained in the same manner as described above. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle size (μm) 2.45 Coefficient of variation (%) 28

(Example 10)
A flocculant (primary sodium chloride, manufactured by Wako Pure Chemical Industries, Ltd.) 18 parts by weight is further added to 600 parts by weight of the aqueous dispersion of particles before washing with the ion-exchanged water prepared in Example 1, and Claremix W Motion. A water dispersion of agglomerated particles was produced by agglomerating under the following agglomeration conditions using

<Aggregating conditions>
Set temperature 62 ℃
Rotation speed (rotor / stator) 18000rpm / 0rpm
Set temperature holding time 10 minutes

The aqueous dispersion of aggregated particles obtained as described above was thoroughly washed with ion-exchanged water and then dried to obtain the toner of Example 6. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 5.14 Coefficient of variation (%) 20

(Comparative Example 1)
A toner of Comparative Example 1 was obtained in the same manner as in Example 1 except that the set temperature was changed from 200 ° C. to 185 ° C. in the micronization step t3a. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 2.34 Coefficient of variation (%) 48

(Comparative Example 2)
In the micronization step t3a, the process was carried out in the same manner as in Example 1 except that the set temperature was changed from 200 ° C. to 240 ° C. However, the nozzle was clogged and micronization could not be performed. Since the set temperature was too high, it is considered that the melt-kneaded product caused excessive aggregation.

(Comparative Example 3)
The toner of Comparative Example 3 was obtained in the same manner as in Example 1 except that the addition amount of the dispersant was changed from 90 parts by weight to 23 parts by weight in the micronization step t3a and the aggregation step t4 was not performed. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle diameter (μm) 1.12 Coefficient of variation (%) 72

(Comparative Example 4)
To 600 parts by weight of the aqueous dispersion of particles before washing with ion-exchanged water prepared in Comparative Example 1, 18 parts by weight of a flocculant (primary sodium chloride, manufactured by Wako Pure Chemical Industries, Ltd.) is further added. Using motion, the particles were aggregated under the following aggregation conditions to prepare an aqueous dispersion of aggregated particles.

<Aggregating conditions>
Set temperature 62 ℃
Rotation speed (rotor / stator) 18000rpm / 0rpm
Set temperature holding time 10 minutes

The aqueous dispersion of aggregated particles obtained as described above was thoroughly washed with ion-exchanged water and then dried to obtain the toner of Comparative Example 4. The volume average particle diameter and coefficient of variation measured with a flow type particle image analyzer (FPIA-2000 type) were as follows.
Volume average particle size (μm) 5.42 Coefficient of variation (%) 38

[Production of wet toner]
By adding 97 parts by weight of ISOPAR L (trade name, manufactured by Showa Shell Sekiyu KK) to 3 parts by weight of the toners of Examples 1-9 and Comparative Examples 1-3, Examples 1-9, Wet toners containing the toners of Comparative Examples 1 to 3 were obtained.

[Production of dry toner]
By adding 1.5 parts by weight of silica fine particles (trade name: R972, manufactured by Nippon Aerosil Co., Ltd.) as an external additive to 100 parts by weight of the toner of Example 10 and Comparative Example 4, Example 10 was added. A dry toner containing the toner of Comparative Example 4 was obtained.

[Preparation of two-component developer]
Using a ferrite core carrier having a volume average particle diameter of 45 μm as the carrier, a V-type mixer (trade name) is used so that the coverage of the dry toner containing the toners of Example 10 and Comparative Example 4 with respect to the carrier becomes 60%. : V-5, manufactured by Tokuju Kogyo Co., Ltd.) for 20 minutes each to prepare a two-component developer containing the toners of Example 10 and Comparative Example 4.
Table 1 shows a list of physical properties relating to the particles obtained in Examples 1 to 10 and Comparative Examples 1 to 4.

  Using each of the wet toners prepared with the toners obtained in Examples 1 to 9 and Comparative Examples 1 to 3, the image forming apparatus 201 shown in FIG. 3 outputs an image as follows, and the image is reproduced with the image. And cleaning properties were evaluated.

  For image formation, the photosensitive drum 211 was rotated clockwise at a speed of 20 cm / s to 100 cm / s, and the photosensitive drum 211 was uniformly charged so that the surface had a potential of about −500V. Next, an electrostatic latent image is formed on the surface of the photosensitive drum 211 by irradiating the photosensitive drum 211 with a laser beam based on the image data, and the electrostatic latent image is exposed by developing wet toner on the surface. Turned into. At this time, the gap between the photosensitive drum 211 and the developing roller 210 is about 100 μm, and a bias of about −400 V was applied to the surface of the developing roller 210 in order to promote the adhesion of the wet toner. The exposed toner image was transferred onto the conveyed paper. At this time, a voltage of about +1000 V was applied to the transfer roller. The paper on which the toner image was transferred was separated from the intermediate transfer roller 226, and then the toner image was fixed with heat and pressure by a heat fixing roller. At this time, the heat fixing roller temperature was heated to about 150 ° C. After the printed paper was discharged, the developer remaining on the surface of the photosensitive drum 211 was removed by a cleaner such as a urethane scraper, and the surface of the photosensitive drum 211 was neutralized with light.

(Image reproducibility)
Under the conditions that each of the copying machines is filled with a two-component developer, and a halftone image having an image density of 0.3 and a diameter of 5 mm can be copied at an image density of 0.3 to 0.5, the line width is A manuscript on which an original image with a fine line of exactly 100 μm was formed was copied onto a recording medium, and the obtained copy image was used as a measurement sample. The image density is an optical reflection density measured by a reflection densitometer (trade name: RD-918, manufactured by Macbeth).

  The fine line formed on the measurement sample is magnified 100 times by a particle analyzer (trade name: Luzex 450, manufactured by Nireco Co., Ltd.), and a copy image is displayed by an indicator from the monitor image on which the fine line magnified 100 times is projected. The line width of the thin line formed on was measured.

The thin line formed in the copy image has irregularities, and the line width of the thin line varies depending on the measurement position. Therefore, the line width is measured at a plurality of measurement positions, and the average value of the line widths is calculated. The average value was taken as the line width of the thin line formed on the copy image. At this time, the line width less than 100 μm due to transfer failure or the like was not counted, and the line width value less than 100 μm was not used when calculating the average value of the line width. The line width of the thin line formed on the copy image was divided by the original image line width of 100 μm, and the obtained value was multiplied by 100 to obtain the value of fine line reproducibility. The closer the value of fine line reproducibility is to 100, the better the reproducibility of fine lines, the better the image reproducibility, and the better the resolution, indicating that the image reproducibility is better.
Image reproducibility was evaluated based on the following evaluation criteria.
○: Good. The fine line reproducibility value is 100 or more and less than 105.
Δ: Yes. The fine line reproducibility value is 105 or more and less than 115.
X: Defect. The fine line reproducibility value is 115 or more.

[Cleanability]
The halftone image used in the above image reproducibility was output, and the surface of the photoreceptor after cleaning near the latent image was observed with an optical microscope. The determination was made according to the following criteria.
○: Good. Residual toner particles cannot be confirmed.
Δ: Yes. A slight amount of residual toner particles can be confirmed.
X: Defect. Residual toner particles are scattered.

[Transferability]
Transferability was evaluated using transfer efficiency. The transfer efficiency is the ratio of the amount of toner transferred from the surface of the photosensitive drum to the intermediate transfer belt with respect to the amount of toner on the surface of the photosensitive drum in the primary transfer. The amount of toner on the surface of the photosensitive drum before transfer is sucked using a charge amount measuring device (trade name: 210HS-2A, manufactured by Trek Japan Co., Ltd.) in a state where the solvent is completely dried. The quantity was obtained by measuring. The amount of toner transferred to the intermediate transfer belt was also obtained in the same manner.

The transfer efficiency was calculated by the following formula (4).
Transfer efficiency [%] = (Amount of toner transferred to the intermediate transfer belt
/ Toner amount on the surface of the photosensitive drum before transfer) × 100 (4)

The evaluation criteria are as follows.
A: Very good. The transfer efficiency is 98% or more.
○: Good. The transfer efficiency is 95% or more and less than 98%.
Δ: No problem in actual use. The transfer efficiency is 90% or more and less than 95%.
X: Defect. Transfer efficiency is less than 90%.
.

〔Comprehensive evaluation〕
Based on the evaluation of the image reproducibility, the cleaning property, and the transfer property, the wet toner of the present invention was comprehensively evaluated.
The overall evaluation criteria are as follows.
A: Very good. The evaluation results of image reproducibility, cleanability and transferability are all “◯” or “◎”.
○: Good. In the evaluation results of image reproducibility, cleaning property, and transferability, there is no cross and Δ is 1 to 2 pieces.
Δ: Yes. The evaluation results of image reproducibility, cleaning property and transferability are all Δ.
X: Defect. At least one of the evaluation results of image reproducibility, cleaning performance, and transferability is x. Or, the toner cannot be manufactured.

  Table 2 shows the evaluation results and comprehensive evaluation results of the toners obtained in Examples 1 to 9 and Comparative Examples 1 to 3.

  Using the two-component developers containing toner obtained in Example 10 and Comparative Example 4, toner scattering, photoconductor filming, and image reproducibility were evaluated by the following methods.

[Toner scattering]
A two-component developer containing the toner obtained in Example 6 and Comparative Example 8 was filled in a developing tank of a color copying machine (trade name: MX-2700, manufactured by Sharp Corporation), and the temperature was 35 ° C. and relative humidity was 80. The developing tank was idled for 3 hours in a high-temperature and high-humidity environment. It was judged that the smaller the difference between the toner concentration in the two-component developer before idling and the toner concentration in the two-component developer after idling, the better and less the toner scattering. The toner density difference was used as an index of the difference in toner density before and after idling, and the toner density difference was calculated using the following formula (5).
Toner density difference (%) = {(toner density before idling−toner density after idling) / toner density before idling} × 100 (5)

The evaluation criteria are as follows.
A: Very good. The toner density difference is less than 0.5%. The toner density difference is 0.5% or more and less than 1.0%.
Δ: Yes. The toner density difference is 1.0% or more and less than 1.5%.
X: Defect. The toner density difference is 1.5% or more.

[Photoreceptor filming]
Using the color copier, the toner adhesion amount to the developing roller as ^{0.6mg / cm 2 ~0.7mg / cm 2} , the toner adhesion amount of the single-color solid portion of the unfixed toner image formed on the recording medium 0 A continuous live-action test was performed in which an evaluation chart having an original density of 5% including an image solid portion and a character portion was formed on 10000 sheets of recording medium with each toner single color adjusted to 5 mg / cm ² . After a continuous live-action test of 10,000 sheets, a solid image corresponding to the length actually used is output in the longitudinal direction of the developing roller and the photosensitive member, and the obtained solid image is visually observed to obtain a solid image. Filming on the photoreceptor was evaluated by judging whether or not streaks or filming marks were generated. The evaluation criteria are as follows.
○: Good. There are no streaks on the solid image and filming marks on the surface of the photoreceptor.
Δ: Yes. Although there are no streaks on the solid image, filming marks are confirmed on the surface of the photoreceptor.
X: Defect. Streaks on the solid image and filming marks are confirmed on the surface of the photoreceptor.

(Image reproducibility)
Under the conditions that each of the copying machines is filled with a two-component developer, and a halftone image having an image density of 0.3 and a diameter of 5 mm can be copied at an image density of 0.3 to 0.5, the line width is A manuscript on which an original image with a fine line of exactly 100 μm was formed was copied onto a recording medium, and the obtained copy image was used as a measurement sample. The image density is an optical reflection density measured by a reflection densitometer (trade name: RD-918, manufactured by Macbeth).

  The fine line formed on the measurement sample is magnified 100 times by a particle analyzer (trade name: Luzex 450, manufactured by Nireco Co., Ltd.), and a copy image is displayed by an indicator from the monitor image on which the fine line magnified 100 times is projected. The line width of the thin line formed on was measured.

The thin line formed in the copy image has irregularities, and the line width of the thin line varies depending on the measurement position. Therefore, the line width is measured at a plurality of measurement positions, and the average value of the line widths is calculated. The average value was taken as the line width of the thin line formed on the copy image. At this time, the line width less than 100 μm due to transfer failure or the like was not counted, and the line width value less than 100 μm was not used when calculating the average value of the line width. The line width of the thin line formed on the copy image was divided by the original image line width of 100 μm, and the obtained value was multiplied by 100 to obtain the value of fine line reproducibility. The closer the value of fine line reproducibility is to 100, the better the reproducibility of fine lines, the better the image reproducibility, and the better the resolution, indicating that the image reproducibility is better.
Image reproducibility was evaluated based on the following evaluation criteria.
A: Very good. The fine line reproducibility value is 100 or more and less than 105.
○: Good. The fine line reproducibility value is 105 or more and less than 115.
Δ: Yes. The fine line reproducibility value is 115 or more and less than 125.
X: Defect. The fine line reproducibility value is 125 or more.
[Transferability]
Transferability was evaluated using transfer efficiency. The transfer efficiency is the ratio of the amount of toner transferred from the surface of the photosensitive drum to the intermediate transfer belt with respect to the amount of toner on the surface of the photosensitive drum in the primary transfer. The amount of toner on the surface of the photosensitive drum before transfer was obtained by suction using a charge amount measuring device (trade name: 210HS-2A, manufactured by Trek Japan Co., Ltd.) and measuring the amount of the sucked toner. . The amount of toner transferred to the intermediate transfer belt was also obtained in the same manner.
The transfer efficiency was calculated by the following formula (6).
Transfer efficiency [%] = (Amount of toner transferred to the intermediate transfer belt
/ Toner amount on surface of photosensitive drum before transfer) × 100 (6)

The evaluation criteria are as follows.
A: Very good. The transfer efficiency is 98% or more.
○: Good. The transfer efficiency is 95% or more and less than 98%.
Δ: No problem in actual use. The transfer efficiency is 90% or more and less than 95%.
X: Defect. Transfer efficiency is less than 90%.

〔Comprehensive evaluation〕
The overall evaluation criteria are as follows.
A: Very good. The evaluation results of toner scattering, photoconductor filming, image reproducibility, and transferability do not have Δ and X.
○: Good. In the evaluation results of toner scattering, photoconductor filming, image reproducibility, and transferability, there is no x and Δ is one.
Δ: Yes. The evaluation results of toner scattering, photoconductor filming, image reproducibility, and transferability have no x, and Δ is 2 or more.
X: Defect. There is at least one x in the evaluation results of toner scattering, photoconductor filming, image reproducibility, and transferability.

  Table 3 shows the evaluation results and comprehensive evaluation results of the toners obtained in Example 10 and Comparative Example 4.

  As shown in Table 1, when agglomerated particles are produced by the method for producing agglomerated particles of the present invention, agglomerated particles having a non-spherical shape, a narrow particle size distribution, and a submicron particle size can be obtained. In Example 4, the particle size of the aggregated particles was less than 4 times the particle size of the fine particles, and therefore the shape of the aggregated particles was more distorted than in the other examples. In Example 5, the particle diameter of the fine particles was less than 0.05 μm, and there were fine particles that could not be aggregated. Therefore, the value of the coefficient of variation was larger than that of the other examples.

  As shown in Tables 2 and 3, the toner of the present invention containing the aggregated particles of the present invention has a good cleaning property and can stably form a high-quality image. Further, when used as a dry toner, toner scattering can be suppressed, and adverse effects on the human body can be prevented. In Example 4 and Example 7, the value of SF1 was larger than in the other examples, and fine particles of toner particles were generated in the developing tank, so that the image reproducibility was lowered. In Example 5, since the value of the coefficient of variation was larger than that in the other examples, the image reproducibility was lowered. In Example 6, both the values of SF1 and SF2 are smaller than those of the other examples and have a slightly rounded shape. However, since the particle diameter of the toner is relatively larger than that of the other examples, it is easily caught by the cleaning blade. The cleaning property was good. However, the image reproducibility was lowered due to the relatively large particle size compared to the other examples.

  In Comparative Example 1 in which the set temperature is low in the fine particle forming process, both the value of SF1 and the value of SF2 are larger than those of the example, and the degree of fusion between the fine particles is weak. The reproducibility was poor. Since the shape of the toner manufactured by the pulverization method of Patent Document 2 is similar to the shape of the toner of Comparative Example 1, it can be estimated that the image reproducibility of the toner manufactured by the manufacturing method of Patent Document 2 is poor. . In Comparative Example 3 in which the aggregation process is not performed, the toner is exposed to a high temperature far exceeding the melting point of the binder resin in the micronization process, and the shape of most of the toner particles becomes spherical. Reproducibility was also reduced. Since the shape of the toner manufactured by the manufacturing method of Patent Document 3 using the high-pressure processing method is similar to the shape of the toner of Comparative Example 1, the cleaning property and image quality of the toner manufactured by the manufacturing method of Patent Document 3 are also similar. It can be estimated that the reproducibility is poor.

It is a flowchart which shows the procedure of the manufacturing method of the aggregated particle of this Embodiment. It is a schematic sectional drawing which shows typically the structure of the image forming apparatus 1 of the dry process which is 5A Embodiment of this invention. It is a schematic sectional drawing which shows typically the structure of the image forming apparatus 201 of the wet process which is 5B embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus of dry process 2 Toner image forming means 3 Transfer means 4 Fixing means 5 Recording material supply means 6 Discharge means 201 Wet process image forming apparatus 211 Photosensitive drum 212 Charging device 202 Toner image forming means 214 Developing device 203 Transfer Device 215 Cleaning roller

Claims (13)

Using a high-pressure machine having a stepwise pressure release mechanism, a liquid medium containing a polymer dispersant and a treated product is treated at a temperature higher by 100 ° C. or more and 150 ° C. or less than the flow tester outflow start temperature of the treated product. A dispersion preparing step of preparing a dispersion in which the treated particles are dispersed in a liquid medium after being finely divided;
An aggregating step of aggregating the fine particles contained in the dispersion.   2. The method for producing aggregated particles according to claim 1, wherein a volume average particle diameter of the fine particles contained in the dispersion liquid is 0.05 μm or more and 0.50 μm or less.   The method for producing aggregated particles according to claim 1 or 2, wherein the volume average particle diameter of the aggregated particles is 4 to 40 times the volume average particle diameter of the fine particles.   Aggregated particles obtained by the method for producing aggregated particles according to any one of claims 1 to 3.   The aggregated particles according to claim 4, wherein the processed product contains at least a resin.   The aggregated particle according to claim 4, wherein the processed product contains at least a colorant.   A toner comprising the aggregated particles according to claim 5.   A toner comprising the toner base particles coated with the aggregated particles according to claim 5.   9. The toner according to claim 7, wherein the resin has a glass transition temperature of 40 ° C. or more and 70 ° C. or less, and a weight average molecular weight of the resin of 10,000 or more and 300,000 or less.   The toner according to claim 7, further comprising a release agent.   A developer comprising the toner according to claim 7.   12. A developing device comprising: developing a latent image formed on an image carrier using the developer according to claim 11 to form a toner image. An image carrier on which a latent image is formed;
A latent image forming means for forming a latent image on the image carrier;
An image forming apparatus comprising: the developing device according to claim 12.

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