Electrophotographic apparatus and image forming method

Abstract

To provide an image formation method for suppressing the generation of a streak-like image defect even when using an electrophotographic photoreceptor which uses a resin with high abrasion resistance on its surface in combination with a toner including a resin excellent in low-temperature fixability.SOLUTION: In an electrophotographic device, a surface layer of an electrophotographic photoreceptor is a polymer film of a composition which contains a compound selected from a group made of compounds with a guanamine structure and compounds with a melamine structure and a specific charge transporting material. A toner includes toner particles which contain a resin A having a unit with a specific structure. A content ratio of the unit with the specific structure in the resin A is 30.0 mass% to 100.0 mass%.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an electrophotographic apparatus and an image forming method. [Background technology]

[0002] The surface of an electrophotographic photoreceptor used in an electrophotographic apparatus is subjected to electrical and mechanical external forces during a charging process and a cleaning process, and therefore is required to have durability (such as abrasion resistance) against these external forces. In response to this demand, conventionally, improvement techniques have been used, such as using a resin with high abrasion resistance (such as a curable resin) in the surface layer of an electrophotographic photoreceptor (Patent Document 1).

[0003] On the other hand, a major problem caused by increasing the abrasion resistance of the surface of the electrophotographic photoreceptor is the effect on the cleaning performance performed by the cleaning blade. The effects on cleaning performance include problems such as an increase in driving torque caused by an increase in the frictional force between the highly wear-resistant surface of the electrophotographic photosensitive member and the cleaning blade, toner slipping through due to minute vibrations of the cleaning blade, and reversal of the cleaning blade.

[0004] In addition, in recent years, a technique for fixing toner at a low temperature has been proposed in order to reduce the amount of energy used by image forming apparatuses. Patent Document 2 describes a technique related to a toner having a resin containing a crystalline polyester as a resin. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2009-229549 A [Patent Document 2] JP 2005-234046 A Summary of the Invention [Problem to be solved by the invention]

[0006] According to the investigations of the present inventors, when the electrophotographic photoreceptor described in Patent Document 1 is used in combination with a toner having a resin containing a crystalline polyester as a resin (for example, the toner described in Patent Document 2), a streak-like image defect may occur, which is thought to be due to the toner passing through the cleaning portion of the photoreceptor, and this poses a problem.

[0007] An object of the present invention is to provide an image forming method which suppresses the occurrence of streak-like image defects even when an electrophotographic photoreceptor using a resin with enhanced abrasion resistance on the surface is used in combination with a toner having a resin with excellent low-temperature fixing property. [Means for solving the problem]

[0008] The above object can be achieved by the present invention described below. That is, an electrophotographic apparatus having an electrophotographic photosensitive member, charging means for charging the surface of the electrophotographic photosensitive member, image exposure means for irradiating the charged surface of the electrophotographic photosensitive member with image exposure light to form an electrostatic latent image on the surface of the electrophotographic photosensitive member, developing means having toner and developing the electrostatic latent image with the toner to form a toner image on the surface of the electrophotographic photosensitive member, transfer means for transferring the toner image from the surface of the electrophotographic photosensitive member to a transfer material, cleaning means for removing residual toner remaining on the surface of the electrophotographic photosensitive member after transfer by the transfer means with a cleaning blade, and fixing means for fixing the toner image transferred to the transfer material to the transfer material, The surface layer of the electrophotographic photoreceptor is a polymerized film of a composition containing a compound selected from the group consisting of compounds having a guanamine structure and compounds having a melamine structure, and two or more kinds of charge transport materials having a structure represented by the following general formula (I), 1 ~Ar 4 may be the same or different and each independently represents a substituted or unsubstituted aryl group; Ar 5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' 1 -X)n1 R' 2 each c is independently 0 or 1; k is 0 or 1; and the total number of D is 2 to 4; 1 and R' 2 each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; n 1 represents 0 or 1, X represents an oxygen, NH, or sulfur atom, and Y represents -OH, provided that two or more kinds of charge transporting materials having a structure represented by the general formula (I) have two or more -OH represented by Y, and at least one kind of charge transporting material has four -OH represented by Y; [ka] The toner in the developing means has toner particles containing a resin A having a unit represented by the following general formula (II), The resin A is a crystalline resin, The content of the unit represented by the following formula (II) in the resin A is 30.0% by mass to 100.0% by mass: [ka] (In formula (II), R Z1 represents a hydrogen atom or a methyl group, R Z2 represents an alkyl group having 18 to 36 carbon atoms. The electrophotographic apparatus is characterized in that Effect of the Invention

[0009] According to the present invention, even when an electrophotographic photosensitive member having excellent wear resistance is combined with a toner having excellent low-temperature fixing property, cleaning stability can be maintained, and an electrophotographic device can be provided in which image defects due to toner slip-through are suppressed. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus of the present invention. [Diagram 2]FIG. 2 is a diagram showing an example of a state in which an electrophotographic photosensitive member according to the present invention comes into contact with a cleaning blade. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] An embodiment of the present invention is as follows. That is, an electrophotographic apparatus having an electrophotographic photosensitive member, charging means for charging the surface of the electrophotographic photosensitive member, image exposure means for irradiating the charged surface of the electrophotographic photosensitive member with image exposure light to form an electrostatic latent image on the surface of the electrophotographic photosensitive member, developing means having toner and developing the electrostatic latent image with the toner to form a toner image on the surface of the electrophotographic photosensitive member, transfer means for transferring the toner image from the surface of the electrophotographic photosensitive member to a transfer material, cleaning means for removing residual toner remaining on the surface of the electrophotographic photosensitive member after transfer by the transfer means with a cleaning blade, and fixing means for fixing the toner image transferred to the transfer material to the transfer material, The surface layer of the electrophotographic photoreceptor is a polymerized film of a composition containing a compound selected from the group consisting of compounds having a guanamine structure and compounds having a melamine structure, and two or more kinds of charge transporting materials having a structure represented by the following general formula (I): [ka] In general formula (I), Ar 1 ~Ar 4 may be the same or different, and each independently represents a substituted or unsubstituted aryl group; Ar 5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' 1 -X)n 1 R' 2 each c is independently 0 or 1; k is 0 or 1; and the total number of D is 2 to 4; 1 and R' 2 each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; 1represents 0 or 1, X represents an oxygen, NH, or sulfur atom, and Y represents -OH, provided that two or more kinds of charge transporting materials having a structure represented by the general formula (I) have two or more -OH represented by Y, and at least one kind of charge transporting material has four -OH represented by Y; The toner in the developing means has toner particles containing a resin A having a unit represented by the following general formula (II), The content of the unit represented by the following general formula (II) in the resin A is 30.0% by mass to 100.0% by mass: [ka] (In general formula (II), R Z1 represents a hydrogen atom or a methyl group, R Z2 represents an alkyl group having 18 to 36 carbon atoms. The electrophotographic apparatus is characterized in that

[0012] Furthermore, an embodiment according to the present invention is as follows. That is, a charging step of charging the surface of an electrophotographic photoreceptor; an image exposure step of irradiating the charged surface of the electrophotographic photoreceptor with image exposure light to form an electrostatic latent image on the surface of the electrophotographic photoreceptor; a developing step of developing the electrostatic latent image with a toner to form a toner image on the surface of the electrophotographic photoreceptor; a transfer step of transferring the toner image from the surface of the electrophotographic photoreceptor to a transfer material; a cleaning step of removing residual toner remaining on the surface of the electrophotographic photoreceptor after the transfer step by using a cleaning blade; a fixing step of fixing the toner image transferred onto the transfer material; An image forming method comprising: The surface layer of the electrophotographic photoreceptor is A polymerized film of a composition containing a compound selected from the group consisting of compounds having a guanamine structure and compounds having a melamine structure, and two or more kinds of charge transport materials having a structure represented by the following general formula (I): [ka] In general formula (I), Ar 1 ~Ar 4 may be the same or different and each independently represents a substituted or unsubstituted aryl group; Ar 5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' 1 -X)n 1 R' 2 each c is independently 0 or 1; k is 0 or 1; and the total number of D is 2 to 4; 1 and R' 2 each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; 1 represents 0 or 1, X represents an oxygen, NH, or sulfur atom, and Y represents -OH; However, two or more kinds of charge transporting materials having a structure represented by the general formula (I) have two or more -OH groups represented by Y, and at least one kind of charge transporting material has four -OH groups represented by Y; The toner has toner particles containing a resin A having a unit represented by the general formula (II), The resin A is a crystalline resin, The content of the unit represented by the general formula (II) in the resin A is 30.0% by mass to 100.0% by mass. [ka] (In general formula (II), R Z1 represents a hydrogen atom or a methyl group, R Z2 represents an alkyl group having 18 to 36 carbon atoms. The image forming method is characterized in that

[0013] The mechanism by which the image forming method according to one embodiment of the present invention solves the problems described above is believed to be as follows. When a highly wear-resistant curable resin is used for the surface layer of an electrophotographic photoreceptor, the wear force between the electrophotographic photoreceptor and the cleaning blade tends to increase due to deterioration of the electrophotographic photoreceptor surface caused by repeated charging processes. This tendency is particularly noticeable in high-temperature and high-humidity environments, and the cleaning state becomes unstable, which may cause so-called cleaning chatter. In the vicinity of the contact portion between the electrophotographic photoreceptor and the cleaning blade, a stable cleaning state is maintained under a steady state due to the presence of an external additive of the toner, but when the cleaning state becomes unstable, toner particles may enter there and cause the toner to slip through.

[0014] As a result of the inventors' investigation, it was found that the toner slip-through can be effectively suppressed when a toner containing resin A having a unit represented by the general formula (II) of the present invention is used. Although the reason for this is unclear, it is presumed that the toner particles themselves contribute to lubrication, suppressing the toner particles from slipping through.

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail. [Electrophotographic photoreceptor] The surface layer of the electrophotographic photoreceptor according to the present invention is a polymerized film of a composition containing a compound selected from the group consisting of compounds having a guanamine structure and compounds having a melamine structure, and two or more kinds of charge transporting materials having a structure represented by the following general formula (I): [ka] In general formula (I), Ar 1 ~Ar 4 may be the same or different and each independently represents a substituted or unsubstituted aryl group; Ar 5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' 1 -X)n 1 R' 2 -Y, c's each independently represent 0 or 1, k's represents 0 or 1, and the total number of D's is 2 to 4. 1 and R'2 each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; 1 represents 0 or 1, X represents an oxygen, NH, or sulfur atom, and Y represents --OH. However, two or more kinds of charge transporting materials having the structure represented by the general formula (I) have two or more -OH groups represented by Y, and at least one kind of charge transporting material has four -OH groups represented by Y.

[0016] The surface layer here means a layer present on the outermost surface of an electrophotographic photoreceptor. In the electrophotographic photoreceptor according to the present invention, a protective layer is formed on the photosensitive layer formed on the conductive support, and the protective layer serves as a surface layer. In the electrophotographic photoreceptor of the present invention, a conductive layer or an undercoat layer, or both, may be provided between the conductive support and the charge generating layer. The method for producing the electrophotographic photoreceptor according to the present invention includes a method in which the coating liquid for each layer described below is prepared, coated in the desired order, and dried. In this case, the coating liquid can be applied by dip coating, spray coating, inkjet coating, roll coating, die coating, blade coating, curtain coating, wire bar coating, ring coating, etc. Among these, dip coating is preferred from the viewpoint of efficiency and productivity.

[0017] Hereinafter, each of the components, such as the conductive support, the conductive layer, the undercoat layer, the photosensitive layer, and the protective layer, will be described.

[0018] <Conductive support> In the present invention, the electrophotographic photoreceptor has a conductive support. The conductive support may be in the form of a cylinder, a belt, a sheet, or the like. Of these, a cylindrical shape is preferred. The surface of the conductive support may be subjected to electrochemical treatment such as anodization, blasting, cutting, wet honing, treatment with an acidic treatment solution, boehmite treatment, or the like. The material of the conductive support is preferably a metal, a resin, or a glass. Examples of the metal include aluminum, iron, nickel, copper, gold, stainless steel, and alloys thereof. Among them, an aluminum support using aluminum is preferable. In addition, it is preferable that the resin or glass is made conductive by a process such as mixing with or coating with a conductive material.

[0019] <Conductive layer> In the present invention, a conductive layer may be provided on the conductive support. By providing the conductive layer, scratches and irregularities on the surface of the conductive support can be concealed and light reflection on the surface of the conductive support can be controlled. The conductive layer preferably contains conductive particles and a resin.

[0020] The conductive particles may be made of a material such as metal oxide, metal, or carbon black. Examples of metal oxides include zinc oxide, aluminum oxide, indium oxide, silicon oxide, zirconium oxide, tin oxide, titanium oxide, strontium titanate, magnesium oxide, antimony oxide, bismuth oxide, etc. Examples of metals include aluminum, nickel, iron, nichrome, copper, zinc, silver, etc. Among these, it is preferable to use metal oxides as the conductive particles, and it is particularly preferable to use titanium oxide, tin oxide, or zinc oxide. When a metal oxide is used as the conductive particles, the surface of the metal oxide may be treated with a silane coupling agent or the like, or the metal oxide may be doped with an element such as phosphorus or aluminum or an oxide thereof. The conductive particles may have a laminated structure having a core particle and a coating layer that covers the core particle. Examples of the core particle include titanium oxide, barium sulfate, zinc oxide, etc. Examples of the coating layer include metal oxides such as tin oxide. When a metal oxide is used as the conductive particles, the volume average particle size is preferably from 1 nm to 500 nm, and more preferably from 3 nm to 400 nm.

[0021] Examples of the resin include polyester resin, polycarbonate resin, polyvinyl acetal resin, acrylic resin, silicone resin, epoxy resin, melamine resin, polyurethane resin, phenol resin, and alkyd resin. The conductive layer may further contain silicone oil, resin particles, a masking agent such as titanium oxide, and the like.

[0022] The average thickness of the conductive layer is preferably from 1 μm to 50 μm, and particularly preferably from 3 μm to 40 μm. The conductive layer can be formed by preparing a coating solution for the conductive layer containing the above-mentioned materials and solvent, forming a coating film of this, and drying it. Examples of the solvent used in the coating solution include alcohol-based solvents, sulfoxide-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents. Examples of the dispersion method for dispersing the conductive particles in the coating solution for the conductive layer include a method using a paint shaker, a sand mill, a ball mill, and a liquid collision type high-speed disperser.

[0023] <Undercoat layer> In the present invention, an undercoat layer may be provided on the conductive support or the conductive layer. By providing an undercoat layer, the adhesion between layers can be improved and a charge injection blocking function can be imparted. The undercoat layer preferably contains a resin. Alternatively, the undercoat layer may be formed as a cured film by polymerizing a composition containing a monomer having a polymerizable functional group.

[0024] Examples of the resin include polyester resin, polycarbonate resin, polyvinyl acetal resin, acrylic resin, epoxy resin, melamine resin, polyurethane resin, phenol resin, polyvinyl phenol resin, alkyd resin, polyvinyl alcohol resin, polyethylene oxide resin, polypropylene oxide resin, polyamide resin, polyamic acid resin, polyimide resin, polyamideimide resin, and cellulose resin.

[0025] Examples of the polymerizable functional group contained in the monomer having a polymerizable functional group include an isocyanate group, a blocked isocyanate group, a methylol group, an alkylated methylol group, an epoxy group, a metal alkoxide group, a hydroxyl group, an amino group, a carboxyl group, a thiol group, a carboxylic anhydride group, and a carbon-carbon double bond group.

[0026] For the purpose of improving electrical properties, the undercoat layer may further contain an electron transporting material, a metal oxide, a metal, a conductive polymer, etc. Among these, it is preferable to use an electron transporting material or a metal oxide. Examples of the electron transport substance include a quinone compound, an imide compound, a benzimidazole compound, a cyclopentadienylidene compound, a fluorenone compound, a xanthone compound, a benzophenone compound, a cyanovinyl compound, an aryl halide compound, a silole compound, a boron-containing compound, etc. An electron transport substance having a polymerizable functional group may be used as the electron transport substance, and the undercoat layer may be formed as a cured film by copolymerizing the electron transport substance with the monomer having the polymerizable functional group described above. Examples of metal oxides include indium tin oxide, tin oxide, indium oxide, titanium oxide, strontium titanate, zinc oxide, aluminum oxide, silicon dioxide, etc. Examples of metals include gold, silver, aluminum, etc. The undercoat layer may further contain an additive.

[0027] The average thickness of the undercoat layer is preferably from 0.1 to 50 μm, and particularly preferably from 15 to 50 μm. The undercoat layer can be formed by preparing a coating solution for the undercoat layer containing the above-mentioned materials and solvent, forming a coating film from the coating solution, and drying and / or curing the coating solution. Examples of the solvent used in the coating solution include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.

[0028] <Middle Class> An intermediate layer may further be provided between the undercoat layer and the photosensitive layer. The intermediate layer is, for example, a layer containing a resin, and examples of the resin include polymer compounds such as acetal resin, polyvinyl alcohol resin, polyvinyl acetal resin, polyurethane resin, polyester resin, acrylic resin, and methacrylic resin. The intermediate layer may be a layer containing an organometallic compound. The organometallic compound used in the intermediate layer may be an organometallic compound containing a metal atom such as zirconium, silicon, titanium, aluminum, or manganese.

[0029] <Photosensitive layer> The photosensitive layer of an electrophotographic photoreceptor is mainly classified into (1) a multi-layer type photosensitive layer and (2) a single-layer type photosensitive layer. (1) The multi-layer type photosensitive layer has a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material. (2) The single-layer type photosensitive layer is a photosensitive layer that contains both a charge generation material and a charge transport material.

[0030] (1) Laminated photosensitive layer The laminated type photosensitive layer has a charge generating layer and a charge transport layer.

[0031] (1-1) Charge generation layer The charge generating layer preferably contains a charge generating material and a resin.

[0032] Examples of the charge generating material include azo pigments, perylene pigments, polycyclic quinone pigments, indigo pigments, and phthalocyanine pigments. Among these, azo pigments and phthalocyanine pigments are preferred. Among phthalocyanine pigments, oxytitanium phthalocyanine pigments, chlorogallium phthalocyanine pigments, and hydroxygallium phthalocyanine pigments are preferred. The content of the charge generating material in the charge generating layer is preferably from 40% by mass to 85% by mass, and more preferably from 60% by mass to 80% by mass, based on the total mass of the charge generating layer.

[0033] Examples of the resin include polyester resin, polycarbonate resin, polyvinyl acetal resin, polyvinyl butyral resin, acrylic resin, silicone resin, epoxy resin, melamine resin, polyurethane resin, phenol resin, polyvinyl alcohol resin, cellulose resin, polystyrene resin, polyvinyl acetate resin, polyvinyl chloride resin, etc. Among these, polyvinyl butyral resin is more preferable.

[0034] The charge generating layer may further contain additives such as an antioxidant and an ultraviolet absorbing agent, etc. Specific examples of such additives include hindered phenol compounds, hindered amine compounds, sulfur compounds, phosphorus compounds, and benzophenone compounds.

[0035] The average thickness of the charge generating layer is preferably from 0.1 to 1 μm, and more preferably from 0.15 to 0.4 μm. The charge generating layer can be formed by preparing a coating solution for the charge generating layer containing the above-mentioned materials and solvent, forming a coating film of this, and drying it. Examples of the solvent used in the coating solution include alcohol-based solvents, sulfoxide-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.

[0036] (1-2) Charge transport layer The charge transport layer contains a charge transport material and a resin.

[0037] Examples of the charge transport material include polycyclic aromatic compounds, heterocyclic compounds, hydrazone compounds, styryl compounds, enamine compounds, benzidine compounds, triarylamine compounds, and resins having groups derived from these materials. Among these, triarylamine compounds and benzidine compounds are preferred. These may be used alone or in combination of two or more. The content of the charge transport material in the charge transport layer is preferably from 25% by weight to 70% by weight, and more preferably from 30% by weight to 55% by weight, based on the total weight of the charge transport layer.

[0038] Examples of the resin include polyester resin, polycarbonate resin, acrylic resin, polystyrene resin, etc. Among these, polycarbonate resin and polyester resin are preferable.

[0039] The charge transport layer may further contain additives such as antioxidants, ultraviolet absorbers, plasticizers, leveling agents, slipping agents, and abrasion resistance improvers. Specific examples of such additives include hindered phenol compounds, hindered amine compounds, sulfur compounds, phosphorus compounds, benzophenone compounds, siloxane-modified resins, silicone oils, fluororesin particles, polystyrene resin particles, polyethylene resin particles, silica particles, alumina particles, and boron nitride particles.

[0040] The thickness of the charge transport layer is preferably from 5 to 50 μm, and particularly preferably from 10 to 30 μm.

[0041] The charge transport layer can be formed by preparing a coating solution for the charge transport layer containing the above-mentioned materials and solvent, forming a coating film of this, and drying it. Examples of the solvent used in the coating solution include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents. Among these solvents, ether-based solvents or aromatic hydrocarbon-based solvents are preferred.

[0042] (2) Single-layer photosensitive layer The single-layer type photosensitive layer can be formed by preparing a coating solution for the photosensitive layer containing a charge generating material, a charge transporting material, a resin and a solvent, forming a coating film of this, and drying it. The charge generating material, the charge transporting material and the resin are the same as the examples of materials in "(1) Multi-layer type photosensitive layer" above.

[0043] <Protective layer (surface layer)> The protective layer serving as the surface layer of the electrophotographic photoreceptor is a polymerized film of a composition containing a compound selected from the group consisting of guanamine compounds and melamine compounds, and two or more kinds of charge transport materials having the structure represented by formula (I) above.

[0044] (Guanamine compounds) In the present invention, the guanamine compound used in the protective layer means a compound having a guanamine skeleton, such as acetoguanamine, benzoguanamine, formoguanamine, steroguanamine, spiroguanamine, and cyclohexylguanamine.

[0045] In the present invention, the guanamine compound is preferably one selected from the compounds represented by the general formula (A) and their multimers. The reason for this is that such compounds contain a functional group (R 1 This is thought to be because the polymer has a high molecular weight (equivalent to 1000 nm), which suppresses the adsorption of discharge gases and moisture, and because there are up to four cross-linking sites in one molecule, which results in a highly cross-linked film. [ka]

[0046] In formula (A), R 1 represents an alkyl group having 1 to 10 carbon atoms, a phenyl group having 6 to 10 carbon atoms, or an alicyclic hydrocarbon group having 4 to 10 carbon atoms. In particular, a phenyl group having 6 to 10 carbon atoms is preferable. R2 to R5 each independently represent a hydrogen atom or -CH2-OR 16 R 16 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. 2 ~R 5 -CH2-OR 16 And R 16 is preferably a methyl group or an n-butyl group.

[0047] The alkyl group may be linear or branched. The alkyl group, phenyl group, and alicyclic hydrocarbon group may be unsubstituted or may have a substituent. R 1 When represents an alkyl group, it preferably contains 1 to 8 carbon atoms, and more preferably 1 to 5 carbon atoms. R 1When represents a phenyl group, the number of carbon atoms is more preferably from 6 to 8. Furthermore, examples of the substituent of the phenyl group include a methyl group, an ethyl group, and a propyl group. R 1 When represents an alicyclic hydrocarbon group, the number of carbon atoms is preferably 5 to 8. Furthermore, examples of the substituent of such an alicyclic hydrocarbon group include a methyl group, an ethyl group, and a propyl group.

[0048] R 16 When represents an alkyl group, the carbon number is preferably 1 to 8, and more preferably 1 to 6. Furthermore, examples of the substituent of such an alkyl group include a methyl group, an ethyl group, and a butyl group.

[0049] The compound represented by formula (A) can be synthesized by any known method, for example, a method using guanamine and formaldehyde. The multimer of the compound represented by the general formula (A) is a compound obtained by polymerizing a plurality of compounds represented by the general formula (A). The degree of polymerization of the multimer is preferably 2 to 200, more preferably 2 to 100. The compound represented by the general formula (A) may be used alone or in combination of two or more. In particular, the compound represented by the general formula (A) is preferably used in combination of two or more kinds, or as a multimer, since the solubility in a solvent is improved.

[0050] Specific examples of the compound represented by general formula (A) are shown below. The specific examples are monomers, but may be polymers of these. In the following example compounds, "Me" represents a methyl group, "Bu" represents a butyl group, and "Ph" represents a phenyl group.

[0051] [ka]

[0052] [ka]

[0053] [ka]

[0054] [ka]

[0055] Examples of commercially available products of the compound represented by general formula (A) include "Super Beckamine(R) L-148-55, Super Beckamine(R) 13-535, Super Beckamine(R) L-145-60, Super Beckamine(R) TD-126" manufactured by Dai Nippon Ink Co., Ltd., and "Nicalac BL-60, Nikalac BX-4000" manufactured by Nippon Carbide Co., Ltd. After synthesis or after purchasing a commercially available product, the compound represented by formula (A) may be dissolved in a suitable solvent such as toluene, xylene, ethyl acetate, etc., and washed with distilled water, ion-exchanged water, etc., or may be treated with an ion-exchange resin to remove the influence of residual catalyst.

[0056] (Melamine compounds) In the present invention, the melamine compound used in the protective layer means a compound having a melamine skeleton, and is preferably one selected from the compounds represented by general formula (B) and polymers thereof. [ka] In formula (B), R 6 ~R 11 each independently represents a hydrogen atom, -CH2-OH, -CH2-OR 12 , -OR 12 Shows.

[0057] R 12 represents an alkyl group having 1 to 5 carbon atoms. Such an alkyl group may be linear or branched. Preferred examples include a methyl group, an ethyl group, and a butyl group.

[0058] The compound represented by the general formula (B) can be synthesized by any known method, for example, a method using melamine and formaldehyde.

[0059] The multimer of the compound represented by general formula (B) is a compound obtained by polymerizing a plurality of compounds represented by general formula (B). The degree of polymerization of the multimer is preferably 2 to 200, more preferably 2 to 100. The compound represented by general formula (B) may be used alone or in combination of two or more. In particular, the compound represented by general formula (B) is preferably used in combination of two or more types, or as a multimer, since the solubility in a solvent is improved.

[0060] Specific examples of the compound represented by formula (B) are shown below. Although the following specific examples are monomers, they may be polymers.

[0061] [ka]

[0062] Commercially available examples of the compound represented by general formula (B) include Super Melami No. 90 (manufactured by NOF Corp.), Super Beckamin® TD-139-60 (manufactured by DIC Corp.), U-Ban 2020 (manufactured by Mitsui Chemicals Corp.), Sumitex Resin M-3 (manufactured by Sumitomo Chemical Co., Ltd.), and Nikalac MW-30 (manufactured by Nippon Carbide Corp.).

[0063] Furthermore, after synthesis or after purchasing a commercially available product, the compound represented by general formula (B) (including polymers) may be dissolved in a suitable solvent such as toluene, xylene, ethyl acetate, etc., and washed with distilled water, ion-exchanged water, etc., or may be treated with an ion-exchange resin to remove the influence of residual catalyst.

[0064] In the present invention, the charge transport material has at least one type of substituent (hereinafter also referred to as "reactive group") selected from -OH, -OCH3, -NH2, -SH and -COOH. Among them, those having at least three such reactive groups are preferable. This is presumably because, by increasing the reactive groups in a specific charge transport material, the crosslink density increases, a crosslinked film with higher strength is obtained, and the rotation torque of the electrophotographic photoreceptor is reduced, particularly when a blade cleaner is used, thereby suppressing damage to the blade and abrasion of the electrophotographic photoreceptor.

[0065] In the present invention, the charge transporting material is preferably a compound represented by the general formula (I). [ka] In general formula (I), Ar 1 ~Ar 4 may be the same or different, and each independently represents a substituted or unsubstituted aryl group; Ar 5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' 1 -X)n 1 R' 2 Each c is independently 0 or 1, k is 0 or 1, and the total number of D is 2 to 4. 1 and R' 2 each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; n 1 represents 0 or 1, X represents an oxygen, NH, or sulfur atom, and Y represents --OH. However, two or more kinds of charge transporting materials having the structure represented by the general formula (I) have two or more -OH groups represented by Y, and at least one kind of charge transporting material has four -OH groups represented by Y.

[0066] Specific examples of the compound represented by formula (I) include the following exemplary compounds.

[0068] [ka]

[0069] [ka]

[0070] [ka]

[0071] [ka]

[0072] [ka]

[0073] [ka]

[0075] The protective layer preferably contains a binder resin, which allows for appropriate surface wear and prevents an increase in the frictional force between the electrophotographic photoreceptor and the cleaning blade. Examples of the binder resin include butyral resin, polyvinyl butyral resin, polyvinyl acetal resin, cellulose resin, polyamide resin, and polyvinyl phenol resin. The content of the binder resin in the protective layer is preferably from 5% by mass to 20% by mass. The weight average molecular weight of the binder resin is preferably from 2,000 to 100,000.

[0076] It is preferable to add an antioxidant to the protective layer for the purpose of preventing deterioration due to acidic gases generated in the charging device. As the antioxidant, known antioxidants such as hindered phenol antioxidants, hindered amine antioxidants, organic sulfur antioxidants, phosphite antioxidants, dithiocarbamate antioxidants, thiourea antioxidants, and benzimidazole antioxidants may be used.

[0077] Furthermore, various particles may be added to the protective layer for the purpose of improving strength and reducing frictional force. Examples of the resin particles include silicone particles, silicone resin particles, silicone surface-treated silica particles, tetrafluoroethylene particles, trifluoroethylene particles, hexafluoropropylene particles, vinyl fluoride particles, and vinylidene fluoride particles.

[0078] The protective layer may contain a metal, a metal oxide, carbon black, or the like. Examples of metals include aluminum, zinc, copper, chromium, nickel, silver, stainless steel, and the like, and also include those in which these metals are vapor-deposited on the surfaces of plastic particles. Examples of metal oxides include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony- or tantalum-doped tin oxide, and antimony-doped zirconium oxide.

[0079] A curing catalyst may be used in the protective layer to promote the curing of the guanamine compound, the melamine compound, and the specific charge transport material. An acid-based catalyst is preferably used as the curing catalyst. As the acid-based catalyst, aliphatic carboxylic acids such as acetic acid, chloroacetic acid, trichloroacetic acid, trifluoroacetic acid, oxalic acid, maleic acid, malonic acid, and lactic acid, aromatic carboxylic acids such as benzoic acid, phthalic acid, terephthalic acid, and trimellitic acid, aliphatic and aromatic sulfonic acids such as methanesulfonic acid, dodecylsulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, and naphthalenesulfonic acid are used, but it is preferable to use a sulfur-containing material.

[0080] The average thickness of the protective layer is preferably from 3 μm to 22 μm. The protective layer can be formed by preparing a coating solution for the protective layer containing the above-mentioned materials and solvent, forming a coating film from the coating solution, and drying and / or curing the coating solution. Examples of the solvent used in the coating solution include alcohol-based solvents, ketone-based solvents, ether-based solvents, sulfoxide-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.

[0081] [Process cartridges, electrophotographic devices] The process cartridge of the present invention integrally supports the electrophotographic photosensitive member described above and at least one means selected from the group consisting of a charging means, a developing means, a transfer means and a cleaning means, and is detachably attachable to the main body of the electrophotographic apparatus. The electrophotographic apparatus of the present invention comprises the electrophotographic photosensitive member, charging means, exposure means, developing means and transfer means described above.

[0082] FIG. 1 shows an example of a schematic configuration of an electrophotographic apparatus having a process cartridge equipped with an electrophotographic photosensitive member. Reference numeral 1 denotes a cylindrical electrophotographic photoreceptor, which is driven to rotate around an axis 2 in the direction of the arrow at a predetermined peripheral speed. The surface of the electrophotographic photoreceptor 1 is charged to a predetermined positive or negative potential by a charging means 3. Although FIG. 1 shows a roller charging method using a roller-type charging member, other charging methods such as a corona charging method, a proximity charging method, and an injection charging method may be adopted. Exposure light 4 is irradiated from an exposure means (not shown) onto the charged surface of the electrophotographic photoreceptor 1, and an electrostatic latent image corresponding to the target image information is formed. The electrostatic latent image formed on the surface of the electrophotographic photoreceptor 1 is developed with toner contained in a developing means 5, and a toner image is formed on the surface of the electrophotographic photoreceptor 1. The toner image formed on the surface of the electrophotographic photoreceptor 1 is transferred to a transfer material 7 by a transfer means 6. The transfer material 7 to which the toner image has been transferred is transported to a fixing means 8, where the toner image is fixed, and the transfer material is printed out outside the electrophotographic device. The electrophotographic device has a cleaning means 9 for removing deposits such as toner remaining on the surface of the electrophotographic photoreceptor 1 after transfer. The electrophotographic apparatus may have a mechanism (not shown) for supplying a lubricant to the surface of the electrophotographic photosensitive member. The electrophotographic apparatus may have a charge removing mechanism for removing charge from the surface of the electrophotographic photosensitive member 1 by pre-exposure light 10 from a pre-exposure means (not shown). In addition, a guide means 12 such as a rail may be provided for mounting and removing the process cartridge 11 of the present invention to and from the main body of the electrophotographic apparatus.

[0083] The electrophotographic photoreceptor of the present invention can be used in laser beam printers, LED printers, copiers, facsimiles, and combination machines thereof.

[0084] [Toner and Developer] The toner used in the present invention has toner particles containing a resin A having a unit represented by the following general formula (II), and the content of the unit represented by the following general formula (II) in the resin A is 30.0 mass % to 100.0 mass %. [ka] In the general formula (II), R Z1 represents a hydrogen atom or a methyl group, RZ2 represents an alkyl group having 18 to 36 carbon atoms.

[0085] The resin A may be a vinyl resin, or a hybrid resin in which a resin other than a vinyl resin is bonded to the unit of general formula (II). When the resin A is a vinyl resin, it may be a random copolymer resin of the polymerizable monomers forming each unit, or it may be a block copolymer. From the viewpoint of low-temperature fixability and ease of control of other properties, it is preferable to use a vinyl resin as the resin A.

[0086] The unit of the general formula (II) has R Z2 The presence of this moiety makes it easier for the resin A to assume a crystalline structure, thereby exhibiting the above-mentioned lubricating properties.

[0087] When the content of the unit of general formula (II) in the resin A is 30.0% by mass to 100.0% by mass, the lubricity of the resin is improved. When the content of the unit of the general formula (II) in the resin A is less than 30.0% by mass, the lubricity of the resin tends to decrease. The content is preferably 50.0% by mass or more. There is no particular upper limit, but when other units described later are contained, it is preferably 90.0% by mass or less.

[0088] The unit represented by the general formula (II) is preferably a unit derived from at least one (first polymerizable monomer) selected from the group consisting of (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms. Examples of (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms include (meth)acrylic acid esters having a linear alkyl group having 18 to 36 carbon atoms [stearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, heneicosanyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, octacosyl (meth)acrylate, myrisyl (meth)acrylate, dotriacontyl (meth)acrylate, etc.] and (meth)acrylic acid esters having a branched alkyl group having 18 to 36 carbon atoms [2-decyltetradecyl (meth)acrylate, etc.]. Among these, from the viewpoint of ease of forming a crystalline structure of the toner, it is preferable to use at least one selected from the group consisting of (meth)acrylic acid esters having a linear alkyl group having a carbon number of 18 to 36. It is more preferable to use at least one selected from the group consisting of linear stearyl (meth)acrylate and behenyl (meth)acrylate. The unit represented by the general formula (II) may be used alone or in combination of two or more kinds.

[0089] The melting point of resin A is preferably 45°C or higher and 90°C or lower, and more preferably 50°C or higher and 85°C or lower.

[0090] The resin A may contain units other than those represented by the general formula (II) above. That is, the resin A may further contain a unit represented by the following formula (III) or general formula (IV). [ka] [ka] In formula (IV), R Z3 represents a hydrogen atom or a methyl group.

[0091] When the resin A is a vinyl resin, examples of the polymerizable monomer forming the unit other than the general formula (II) include the following. The polymerizable monomer forming the unit other than the general formula (II) may be used alone or in combination of two or more. Monomers having a nitrile group; for example, acrylonitrile, methacrylonitrile, etc. Monomers having a hydroxy group; for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc.

[0092] Monomers having an amide group; for example, acrylamide, monomers obtained by reacting an amine having 1 to 30 carbon atoms with a carboxylic acid having 2 to 30 carbon atoms (such as acrylic acid and methacrylic acid) having an ethylenically unsaturated bond by a known method. Monomer having a urea group: for example, a monomer obtained by reacting an amine having 3 to 22 carbon atoms [primary amines (such as normal butylamine, t-butylamine, propylamine, and isopropylamine), secondary amines (such as di-normal ethylamine, di-normal propylamine, and di-normal butylamine), aniline, and cycloxylamine] with an isocyanate having 2 to 30 carbon atoms and an ethylenically unsaturated bond by a known method.

[0093] Monomers having a carboxy group; for example, methacrylic acid, acrylic acid, 2-carboxyethyl (meth)acrylate. Vinyl esters; such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl pivalate, and vinyl octoate.

[0094] Further examples include styrene and its derivatives such as styrene and o-methylstyrene, and (meth)acrylic acid esters such as methyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

[0095] Also included are unsaturated monoolefins such as ethylene, propylene, butylene, isobutylene; and unsaturated polyenes such as butadiene, isoprene. Aromatic divinyl compounds; alkyl chain linked diacrylate compounds; alkyl chain linked diacrylate compounds containing ether linkages; aromatic and ether linkage linked diacrylate compounds; polyester type diacrylates; polyfunctional crosslinkers. Examples of the aromatic divinyl compound include divinylbenzene and divinylnaphthalene. Examples of the diacrylate compounds linked by alkyl chains include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and compounds in which the acrylate of the above compounds is replaced with a methacrylate.

[0096] When the resin A is a vinyl resin, it can be produced using the exemplified polymerizable monomer and polymerization initiator. From the viewpoint of efficiency, the polymerization initiator is preferably used in an amount of 0.05 to 10 parts by mass per 100 parts by mass of the polymerizable monomer.

[0097] The polymerization initiator includes the following. 2,2'-Azobisisobutyronitrile, 2,2'-Azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-Azobis(2,4-dimethylvaleronitrile), 2,2'-Azobis(2-methylbutyronitrile), Dimethyl-2,2'-azobisisobutyrate, 1,1'-Azobis(1-cyclohexanecarbonitrile), 2-Carbamoylazoisobutyronitrile, 2,2'-Azobis(2,4,4-trimethylpentane), 2-Phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2,2'-Azobis(2-methylpropane), Methyl ethyl ketone peroxide, Acetone Ketone peroxides such as ethyl acetone peroxide and cyclohexanone peroxide, 2,2-bis(tert-butylperoxy)butane, tert-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, di-tert-butyl peroxide, tert-butylcumyl peroxide, dicumyl peroxide, α,α'-bis(tert-butylperoxyisopropyl)benzene, isobutyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-Trimethylhexanoyl peroxide, benzoyl peroxide, m-trioyl peroxide, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxycarbonate, dimethoxyisopropyl peroxydicarbonate, di(3-methyl-3-methoxybutyl) peroxycarbonate, acetylcyclohexylsulfonyl peroxide, tert-butyl peroxyacetate, tert-butyl peroxy diisobutyrate, tert-butyl peroxy neodecanoate, tert-butyl peroxy 2-ethylhexanoate, tert-butyl peroxy laurate, tert-butyl peroxy benzoate, tert-butyl peroxy isopropyl carbonate, di-tert-butyl peroxy isophthalate, tert-butyl peroxy allyl carbonate, tert-amyl peroxy 2-ethylhexanoate, di-tert-butyl peroxy hexahydroterephthalate, di-tert-butyl peroxy azelate.

[0098] In addition, when the resin A is a hybrid resin in which a resin other than a vinyl resin is bonded to the above formula (III) unit, the resin other than the vinyl resin can be silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone-indene resin, petroleum resin, etc. Among these, it is preferable to use polyester resin from the viewpoint of low-temperature fixing property and charge control. The polyester resin can be either amorphous polyester or crystalline polyester, but amorphous polyester is more preferable.

[0099] The polyester resin is a resin having a "polyester unit" in the binder resin chain, and specific examples of components constituting the polyester unit include divalent or higher alcohol monomer components and acid monomer components such as divalent or higher carboxylic acids, divalent or higher carboxylic acid anhydrides, and divalent or higher carboxylic acid esters.

[0100] Examples of the dihydric or higher alcohol monomer component include alkylene oxide adducts of bisphenol A such as polyoxypropylene(2.2)-2,2-bis(4-hydroxyphenyl)propane, polyoxypropylene(3.3)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene(2.0)-2,2-bis(4-hydroxyphenyl)propane, polyoxypropylene(2.0)-polyoxyethylene(2.0)-2,2-bis(4-hydroxyphenyl)propane, and polyoxypropylene(6)-2,2-bis(4-hydroxyphenyl)propane; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, and 1,6-hexanediol. Examples of suitable glycerol include 1,4-butadiene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, and 1,3,5-trihydroxymethylbenzene.

[0101] Among these, the alcohol monomer component that is preferably used is an aromatic diol, and the alcohol monomer component that constitutes the polyester resin preferably contains the aromatic diol in a proportion of 80 mol % or more.

[0102] On the other hand, examples of the acid monomer components such as the divalent or higher carboxylic acid, the divalent or higher carboxylic acid anhydride, and the divalent or higher carboxylic acid ester include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, or anhydrides thereof; alkyl dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, glutaconic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid, mesaconic acid, citraconic acid, and itaconic acid, or anhydrides thereof; succinic acid or anhydrides thereof substituted with an alkyl group or alkenyl group having 6 to 18 carbon atoms; and unsaturated dicarboxylic acids or anhydrides thereof such as fumaric acid, maleic acid, and citraconic acid.

[0103] Among these, preferred acid monomer components are polycarboxylic acids such as terephthalic acid, succinic acid, adipic acid, fumaric acid, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, and anhydrides thereof.

[0104] A preferred method for obtaining the hybrid resin is to carry out a polymerization reaction of either or both of the vinyl resin, vinyl copolymer unit, and polyester resin in the presence of a polymer containing a monomer component capable of reacting with each of the vinyl resin, vinyl copolymer unit, and polyester resin.

[0105] The content of the resin A in the toner particles of the toner is preferably 40.0% by mass or more because the effect of the lubrication of the resin described above is easily obtained. More preferably, it is 50.0% by mass or more. There is no particular upper limit, but considering the content of the colorant and release agent contained in the toner particles, it is preferably 90.0% by mass or less.

[0106] The toner of the present invention may contain a resin other than the resin A as necessary for the purpose of improving pigment dispersibility, etc., to the extent that the effect of the present disclosure is not impaired. Examples of the resin other than Resin A include the following. Polyvinyl chloride, phenolic resin, natural resin modified phenolic resin, natural resin modified maleic acid resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane resin, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone-indene resin, petroleum-based resin. The content of the resin other than the resin A in the toner particles of the toner is preferably from 0% by mass to 30.0% by mass.

[0107] <Degree of crystallinity of resin A> The crystallinity of the resin A is preferably from 30% to 70%. When the crystallinity of the resin A is within this range, the lubricating property of the resin, which is the effect of the present invention, is easily exhibited.

[0108] The crystallinity of Resin A can be measured by wide-angle X-ray diffraction and calculated under the following conditions. X-ray diffraction equipment: Bruker AXS D8 ADVANCE X-ray source: Cu-Kα ray (wavelength 0.15418nm) Output: 40kV, 40mA Slit type: Slit DS, SS=1°, RS=0.2mm Measurement range: 2θ=5°~60° Step interval: 0.02° Scan speed: 1° / min

[0109] The wide-angle X-ray diffraction profile obtained under the above measurement conditions is separated into a crystal peak and an amorphous scattering peak, and the degree of crystallinity is calculated from their areas using the following formula. Formula) Crystallinity (%)=Ic / (Ic+Ia)×100 Ic: Total area of ​​crystal peaks detected in the range of 5≦2θ≦60 Ia: Total area of ​​amorphous scattering detected in the range of 5≦2θ≦60 The degree of crystallinity of the resin A of the present invention contained in the toner is measured by isolating the crystalline resin component contained in the toner and using the above-mentioned method. As a method for isolating the crystalline resin component, a method of washing the toner with hexane to dissolve the release agent and non-crystalline resin in the toner can be mentioned.

[0110] <Release agent> The toner particles may contain a wax as a release agent. Examples of such wax include the following: Hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymers, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax; oxides of hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof; waxes whose main component is fatty acid esters such as carnauba wax; and partially or completely deoxidized fatty acid esters such as deoxidized carnauba wax. Saturated straight-chain fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassidic acid, eleostearic acid, and valinaric acid; saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; polyhydric alcohols such as sorbitol; esters of fatty acids such as palmitic acid, stearic acid, behenic acid, and montanic acid with alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, hexamethylene bi saturated fatty acid bisamides such as stearic acid amide; unsaturated fatty acid amides such as ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N,N'-dioleyl adipic acid amide, and N,N'-dioleyl sebacic acid amide; aromatic bisamides such as m-xylene bisstearic acid amide and N,N'-distearyl isophthalic acid amide; fatty metal salts (commonly known as metal soaps) such as calcium stearate, calcium laurate, zinc stearate, and magnesium stearate; waxes grafted onto aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid; partial esters of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; and methyl ester compounds having hydroxyl groups obtained by hydrogenating vegetable oils and fats.

[0111] Among these waxes, from the viewpoint of improving low-temperature fixing property and fixing separation property, preferred are hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax, and fatty acid ester waxes such as carnauba wax, and more preferred are hydrocarbon waxes from the viewpoint of further improving hot offset resistance. The content of the wax is preferably 3 to 20 parts by mass per 100 parts by mass of the binder resin.

[0112] <Coloring agent> The toner may contain a colorant, if necessary. Examples of the colorant include the following.

[0113] Examples of black colorants include carbon black; yellow colorants, magenta colorants, and cyan colorants used to tone the color to black. As colorants, pigments may be used alone, or dyes and pigments may be used in combination. From the viewpoint of image quality of full-color images, it is preferable to use dyes and pigments in combination. Examples of pigments for magenta toner include the following. CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48:2, 48:3, 48:4, 49, 50, 51, 52, 53, 54, 55, 57:1, 58, 60, 63, 64, 68, 81:1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; CI Pigment Violet 19; CI Bat Red 1, 2, 10, 13, 15, 23, 29, 35.

[0114] Dyes for magenta toners include solvent dyes such as CI Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; CI Disperse Red 9; CI Solvent Violet 8, 13, 14, 21, 27; CI Disperse Violet 1; basic dyes such as CI Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; and CI Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

[0115] Pigments for cyan toners include the following: CI Pigment Blue 2, 3, 15:2, 15:3, 15:4, 16, 17; CI Vat Blue 6; CI Acid Blue 45; copper phthalocyanine pigments having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton. Dyes for cyan toners include CI Solvent Blue 70.

[0116] Yellow toner pigments include: CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185; CI Vat Yellow 1, 3, 20. Yellow toner dyes include CI Solvent Yellow 162.

[0117] These colorants may be used alone or in mixture, or further in the form of a solid solution. The colorant is selected in consideration of hue angle, chroma, brightness, light resistance, OHP transparency, and dispersibility in toner. The content of the colorant is preferably 0.1 to 30.0 parts by mass based on the total amount of the resin components.

[0118] <Charge control agent> The toner particles may contain a charge control agent, if necessary. By blending a charge control agent, the charge characteristics can be stabilized and the amount of triboelectric charge can be controlled to an optimum level according to the development system. As the charge control agent, known substances can be used, but particularly preferred are metal compounds of aromatic carboxylic acids, which are colorless, can charge the toner quickly, and can stably maintain a constant charge amount. Examples of negative charge control agents include metal salicylate compounds, metal naphthoate compounds, metal dicarboxylate compounds, polymeric compounds having sulfonic acid or carboxylic acid on the side chain, polymeric compounds having sulfonate or sulfonate ester on the side chain, polymeric compounds having carboxylate or carboxylate ester on the side chain, boron compounds, urea compounds, silicon compounds, and calixarenes. The charge control agent may be added internally or externally to the toner particles. The content of the charge control agent is preferably 0.2 parts by mass to 10.0 parts by mass, more preferably 0.5 parts by mass to 10.0 parts by mass, based on 100 parts by mass of the binder resin.

[0119] <Inorganic fine particles> The toner may contain inorganic fine particles as necessary. The inorganic fine particles may be added internally to the toner particles, or may be mixed with the toner as an external additive. Examples of the inorganic fine particles include silica fine particles, titanium oxide fine particles, alumina fine particles, or composite oxide fine particles thereof. Among the inorganic fine particles, silica fine particles and titanium oxide fine particles are preferred for improving flowability and uniform charging. The inorganic fine particles are preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil, or a mixture thereof. From the viewpoint of improving fluidity, inorganic fine particles as external additives should have a specific surface area of ​​50 m 2 / g to 400m 2 From the viewpoint of improving durability and stability, it is preferable that the inorganic fine particles as the external additive have a specific surface area of ​​10 m 2 / g to 50m2 In order to achieve both improved fluidity and durability and stability, inorganic fine particles having a specific surface area within the above range may be used in combination. The content of the external additive is preferably 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the toner particles. The toner particles and the external additive can be mixed using a known mixer such as a Henschel mixer.

[0120] <Toner softening point (Tm)> From the viewpoint of low-temperature fixability and storage stability, the toner of the present invention preferably has a softening point of 70° C. to 120° C., more preferably 75° C. to 110° C., and even more preferably 100° C. or lower.

[0121] The softening point of the toner is measured using a constant load extrusion type capillary rheometer "Flow characteristic evaluation device Flow Tester CFT-500D" (manufactured by Shimadzu Corporation) according to the manual that comes with the device. With this device, a constant load is applied from above the measurement sample with a piston while the measurement sample filled in a cylinder is heated and melted, and the molten measurement sample is extruded from the die at the bottom of the cylinder, and a flow curve showing the relationship between the piston descent amount and temperature can be obtained.

[0122] The softening point is the "melting temperature in the 1 / 2 method" described in the manual attached to the "Flow property evaluation device Flow Tester CFT-500D." The melting temperature in the 1 / 2 method is calculated as follows. First, calculate half the difference between the amount of piston descent when the outflow ends (end of outflow, Smax) and the amount of piston descent when the outflow starts (minimum point, Smin) (this is X. X=(Smax-Smin) / 2). Then, the temperature of the flow curve when the amount of piston descent is the sum of X and Smin is the melting temperature in the 1 / 2 method. The measurement sample is prepared by compressing approximately 1.0 g of resin at approximately 10 MPa for approximately 60 seconds using a tablet molding machine (e.g., NT-100H, manufactured by NPA Systems) in an environment of 25°C to form a cylindrical shape with a diameter of approximately 8 mm.

[0123] The specific operations for the measurement are performed according to the manual that comes with the device. The measurement conditions for the CFT-500D are as follows. Test mode: Temperature rise method Starting temperature: 50℃ Achieved temperature: 200℃ Measurement interval: 1.0℃ Heating rate: 4.0℃ / min Piston cross-sectional area: 1.000cm2 Test load (piston load): 10.0kgf (0.9807MPa) Preheat time: 300 seconds Die hole diameter: 1.0mm Die length: 1.0mm

[0124] <Developer> The toner can be used as a one-component developer, but in order to further improve dot reproducibility and provide stable images over a long period of time, it is preferable to mix the toner with a magnetic carrier and use it as a two-component developer. As the magnetic carrier, generally known carriers can be used, such as iron oxide; metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, and rare earth elements, alloy particles thereof, and oxide particles thereof; magnetic materials such as ferrite; and magnetic material-dispersed resin carriers (so-called resin carriers) that contain a magnetic material and a binder resin that holds the magnetic material in a dispersed state. When the toner is mixed with a magnetic carrier to be used as a two-component developer, the mixing ratio of the magnetic carrier is preferably 2% by mass to 15% by mass, and more preferably 4% by mass to 13% by mass, in terms of the toner concentration in the two-component developer.

[0125] <Toner manufacturing method> The method for producing the toner of the present invention is not particularly limited, and known methods such as a pulverization method, a suspension polymerization method, a dissolution suspension method, an emulsion aggregation method, and a dispersion polymerization method can be used.

[0126] <Method of measuring weight average particle size (D4) of toner> The weight-average particle size (D4) of the toner is calculated as follows. The measurement device used is a precision particle size distribution measurement device using the narrow hole electrical resistance method, "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.), equipped with a 100 μm aperture tube. The measurement conditions are set and the measurement data is analyzed using the accompanying dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.). The measurement is performed with an effective measurement channel count of 25,000 channels. The electrolyte solution used for the measurement is prepared by dissolving special grade sodium chloride in ion-exchanged water to a concentration of approximately 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter).

[0127] Before performing measurements and analysis, the dedicated software is set up as follows. In the "Change Standard Measurement Method (SOM)" screen of the dedicated software, set the total count number in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using "Standard Particle 10.0 μm" (Beckman Coulter). Press the "Measure Threshold / Noise Level" button to automatically set the threshold and noise level. In addition, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check "Flush aperture tube after measurement." In the "Pulse to particle size conversion setting" screen of the dedicated software, set the bin interval to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range to 2 μm to 60 μm.

[0128] The specific measurement method is as follows. (1) Pour about 200 mL of the electrolyte solution into a 250 mL round-bottom glass beaker made exclusively for the Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 revolutions per second. Then, use the "Aperture Tube Flush" function of the dedicated software to remove dirt and air bubbles from inside the aperture tube. (2) Place about 30 mL of the electrolyte solution in a 100 mL flat-bottom glass beaker. Add about 0.3 mL of a solution of "Contaminon N" (a 10% aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments made from nonionic surfactants, anionic surfactants, and organic builders, manufactured by Wako Pure Chemical Industries, Ltd.) diluted 3 times with ion-exchanged water as a dispersant. (3) Prepare an ultrasonic disperser "Ultrasonic Dispersion System Tetora150" (manufactured by Nikkaki Bios Co., Ltd.) that has two built-in oscillators with an oscillation frequency of 50 kHz and a phase shift of 180 degrees and an electrical output of 120 W. Place 3.3 L of ion-exchanged water in the water tank of the ultrasonic disperser, and add about 2 mL of the above-mentioned Contaminon N to this water tank. (4) The beaker (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid surface of the electrolyte solution in the beaker is maximized. (5) While the electrolyte solution in the beaker in (4) is irradiated with ultrasonic waves, 10 mg of toner particles are added little by little to the electrolyte solution and dispersed. Then, ultrasonic dispersion treatment is continued for another 60 seconds. During ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be between 10°C and 40°C. (6) Using a pipette, add the electrolyte solution (5) in which the toner particles are dispersed to the round-bottom beaker (1) placed in the sample stand, and adjust the measurement concentration to about 5%. Then, measurements are continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software that comes with the device, and the weight-average particle size (D4) is calculated. Note that when the dedicated software is set to Graph / Volume%, the "Average diameter" on the "Analysis / Volume Statistics (Arithmetic Mean)" screen is the weight-average particle size (D4).

[0129] <Method for measuring average circularity of toner> The average circularity of the toner is measured using a flow type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) under the measurement and analysis conditions during the calibration process. The measurement principle of the flow-type particle image analyzer "FPIA-3000" (Sysmex Corporation) is to capture still images of flowing particles and perform image analysis. The sample added to the sample chamber is sent to the flat sheath flow cell by the sample suction syringe. The sample sent to the flat sheath flow is sandwiched between the sheath liquid and forms a flat flow. The sample passing through the flat sheath flow cell is irradiated with a strobe light at 1 / 60 second intervals, making it possible to capture still images of the flowing particles. In addition, since the flow is flat, the image is captured in focus. The particle images are captured by a CCD camera, and the captured images are processed with an image processing resolution of 512 x 512 pixels (0.37 x 0.37 μm per pixel), and the contours of each particle image are extracted, and the projected area S and perimeter L of the particle image are measured.

[0130] Next, the equivalent circle diameter and circularity are calculated using the above area S and perimeter L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of ​​the particle image, and the circularity C is defined as the perimeter of the circle calculated from the equivalent circle diameter divided by the perimeter of the projected particle image, and is calculated using the following formula. Circularity C=2×(π×S)1 / 2 / L When the particle image is circular, the circularity is 1.000, and the greater the degree of unevenness on the outer periphery of the particle image, the smaller the circularity value. After calculating the circularity of each particle, the range of circularity from 0.200 to 1.000 is divided into 800, the arithmetic mean of the resulting circularities is calculated, and this value is taken as the average circularity.

[0131] The specific measurement method is as follows. First, about 20 mL of ion-exchanged water from which impurities such as solids have been removed is placed in a glass container, and about 0.2 mL of a solution of "Contaminon N" (a 10% aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments made from a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries) diluted about three times by mass with ion-exchanged water is added as a dispersant. Add about 0.02 g of the measurement sample and disperse it for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. At this time, cool the dispersion appropriately so that the temperature of the dispersion becomes 10℃ to 40℃. As the ultrasonic disperser, a tabletop ultrasonic cleaner disperser ("VS-150" (manufactured by Velvoclear)) with an oscillation frequency of 50 kHz and an electrical output of 150 W was used. A specified amount of ion-exchanged water was placed in the water tank, and approximately 2 mL of Contaminon N was added to the water tank.

[0132] For the measurement, the flow type particle image analyzer equipped with a standard objective lens (10x) is used, and the particle sheath "PSE-900A" (manufactured by Sysmex Corporation) is used as the sheath liquid. The dispersion liquid prepared according to the procedure is introduced into the flow type particle image analyzer, and 3000 toner particles are measured in the HPF measurement mode and total count mode. The binarization threshold for particle analysis is set to 85%, the analysis particle diameter is set to a circle equivalent diameter of 1.98 μm to 39.96 μm, and the average circularity of the toner is calculated. Before starting the measurement, automatic focus adjustment is performed using standard latex particles (e.g., Duke Scientific's "RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A" diluted with ion-exchanged water). After that, it is preferable to perform focus adjustment every 2 hours from the start of the measurement. EXAMPLES

[0133] The present invention will be described in more detail below with reference to Production Examples and Examples, which are not intended to limit the scope of the present invention. Note that the numbers of parts in the following formulations are all by weight unless otherwise specified.

[0134] [Example of manufacturing electrophotographic photoreceptor] <Production Example of Electrophotographic Photoreceptor 1> ·Support An aluminum cylinder having a length of 357.5 mm, a thickness of 0.7 mm, and an outer diameter of 30 mm was prepared as a support (conductive support). The surface of the prepared aluminum cylinder was machined using a lathe. The cutting conditions were a R0.1 bit, a spindle speed of 10,000 rpm, and a bit feed rate that was continuously changed in the range of 0.03 to 0.06 mm / rpm.

[0135] - Formation of undercoat layer Zinc oxide particles (average particle size: 70 nm, specific surface area: 15 m 2 To this was added 0.75 parts of a silane coupling agent (compound name: N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, product name: KBM603, manufactured by Shin-Etsu Chemical Co., Ltd.), and the mixture was stirred for 2 hours. Thereafter, the tetrahydrofuran was distilled off under reduced pressure, and the mixture was dried by heating at 120°C for 3 hours to obtain surface-treated zinc oxide particles. Next, 25 parts of butyral (product name: BM-1, manufactured by Sekisui Chemical Co., Ltd.) as a polyol and 22.5 parts of blocked isocyanate (product name: Sumidur BL-3173, manufactured by Sumitomo Bayern Urethane Co., Ltd.) were dissolved in 142 parts of methyl ethyl ketone. 100 parts of the surface-treated zinc oxide particles and 1 part of anthraquinone were added to this solution, and the mixture was dispersed in a sand mill using glass beads with a diameter of 1 mm for 5 hours. After the dispersion treatment, 0.008 parts of dioctyltin dilaurate and 6.5 parts of silicone resin particles (Tospearl 145, manufactured by GE Toshiba Silicones) were added and stirred to prepare a coating liquid for an undercoat layer. The obtained coating liquid for undercoat layer was dip-coated onto the support to form a coating film, and the coating film was dried at 190° C. for 24 minutes to form an undercoat layer with a thickness of 25 μm.

[0136] Formation of charge generating layer Next, 15 parts of hydroxygallium phthalocyanine crystals having strong peaks at Bragg angles 2θ±0.2° at 7.4° and 28.2° in CuKα characteristic X-ray diffraction, 10 parts of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nippon Union Carbide Co., Ltd.), and 300 parts of n-butyl alcohol were mixed and dispersed for 4 hours in a sand mill using glass beads with a diameter of 1 mm to prepare a coating solution for the charge generating layer. This charge generating layer coating liquid was dip coated onto the undercoat layer, and the resulting coating was dried at 80° C. for 10 minutes to form a charge generating layer having a thickness of 0.2 μm.

[0137] Formation of charge transport layer A coating liquid for the charge transport layer was prepared by mixing 4 parts of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1']biphenyl-4,4'-diamine as a charge transport material, 6 parts of bisphenol Z type polycarbonate resin (viscosity average molecular weight: 40,000), and 0.1 parts of 2,6-di-t-butyl-4-methylphenol as an antioxidant, and mixing and dissolving the mixture with 24 parts of tetrahydrofuran and 11 parts of toluene. This charge transport layer coating liquid was dip coated onto the charge generating layer to form a coating film, and the resulting coating film was dried at 135° C. for 35 minutes to form a charge transport layer with a thickness of 32 μm.

[0138] Formation of a surface protective layer As a compound having a guanamine structure, 5 parts of the above-mentioned compound (A)-15 were used, and as a charge transport material, the above-mentioned compound 1 -63 copies of 16, 1 A coating solution for a surface protective layer was prepared by mixing and dissolving 27 parts of 1-8, 5 parts of butyral resin as a binder resin, 1 part of 3,5-di-t-butyl-4-hydroxytoluene as an antioxidant, 0.15 parts of dodecylbenzenesulfonic acid, 50 parts of isobutyl alcohol, and 50 parts of cyclopentanol. This coating solution for a surface protective layer was dip-coated on the charge transport layer to form a coating film, and the resulting coating film was air-dried at room temperature for 30 minutes and then heat-treated at 150°C for 1 hour to harden it, forming a surface protective layer with a thickness of 18 μm, and an electrophotographic photoreceptor 1 was obtained.

[0140] <Measuring method for resin melting point> The melting point of the resin is measured using a DSC Q1000 (manufactured by TA Instruments) under the following conditions. Heating rate: 10℃ / min Measurement start temperature: 20℃ End of measurement temperature: 180℃ The melting points of indium and zinc are used for temperature correction of the device detection section, and the heat of fusion of indium is used for heat correction. Specifically, about 5 mg of a sample is weighed out and placed in an aluminum pan, and differential scanning calorimetry is performed using an empty silver pan as a reference. The peak temperature of the maximum endothermic peak in the first heating process is taken as the melting point. The maximum endothermic peak refers to the peak with the largest amount of endothermic heat when there are multiple peaks.

[0141] [Developer manufacturing example] As the resin A, resins A1 to A12 were produced by the following method. (Production example of resin A1) Toluene 150.0 parts Behenyl acrylate (compound represented by structural formula (a-1)) 54.0 parts (90.0% by mass) Methyl methacrylate 6.0 parts Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were put into a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. The reaction vessel was heated to 70°C while stirring at 200 rpm to carry out a polymerization reaction for 12 hours, and a solution in which the polymer of the monomer composition was dissolved in toluene was obtained. Next, the temperature of the solution was lowered to 25°C, and then the solution was poured into 1000.0 parts of methanol while stirring, and the methanol insoluble matter was precipitated. The obtained methanol insoluble matter was filtered, washed with methanol, and then vacuum dried at 40°C for 24 hours to obtain resin A1. [ka]

[0142] (Production example of resin A2) Resin A2 was produced in the same manner as in the Production Example of Resin A1, except that the following structural formula (a-2) was used instead of behenyl acrylate in the Production Example of Resin A1. [ka]

[0143] (Resin A3 manufacturing example) Resin A3 was produced in the same manner as in the Production Example of Resin A1, except that the behenyl acrylate in the Production Example of Resin A1 was replaced with the compound represented by the following structural formula (a-3). [ka]

[0144] (Resin A4 manufacturing example) Toluene 150.0 parts Behenyl acrylate (compound represented by the above structural formula (a-1)) 60.0 parts (100.0% by mass) Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were mixed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Other than that, Resin A4 was produced in the same manner as in the production example of Resin A1.

[0145] (Resin A5 manufacturing example) Toluene 150.0 parts Behenyl acrylate (compound represented by the above structural formula (a-1)) 18.0 parts (30.0% by mass) Methyl methacrylate 42.0 parts Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were mixed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Other than that, Resin A5 was produced in the same manner as in the production example of Resin A1.

[0146] (Production example of resin A6) Toluene 150.0 parts Behenyl acrylate (compound represented by the above structural formula (a-1)) 57.0 parts (95.0% by mass) Acrylic acid 3.0 parts Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were mixed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Other than that, Resin A6 was produced in the same manner as in the production example of Resin A1.

[0147] (Resin A7 manufacturing example) Toluene 150.0 parts Behenyl acrylate (compound represented by the structural formula (a-2)) 18.0 parts (30.0% by mass) Methyl methacrylate 42.0 parts Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were mixed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Other than that, Resin A7 was produced in the same manner as in the production example of Resin A1.

[0148] (Resin A8 manufacturing example) Resin A8 was produced in the same manner as in the Production Example of Resin A1, except that behenyl methacrylate (a compound represented by the following structural formula (a-4)) was used instead of behenyl acrylate in the Production Example of Resin A1. [ka]

[0149] (Resin A9 manufacturing example) Toluene 150.0 parts Behenyl acrylate (compound represented by the above structural formula (a-1)) 54.0 parts (90.0% by mass) Styrene 6.0 parts Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were mixed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Other than that, Resin A9 was produced in the same manner as in the production example of Resin A1.

[0150] (Production example of resin A10) Resin A10 was produced in the same manner as in the Production Example of Resin A1, except that the behenyl acrylate in the Production Example of Resin A1 was replaced with the compound represented by the following structural formula (a-5). [ka]

[0151] (Production example of resin A11) Resin A11 was produced in the same manner as in the Production Example of Resin A1, except that the following structural formula (a-6) was used instead of behenyl acrylate. [ka]

[0152] (Production example of resin A12) Toluene 150.0 parts Behenyl acrylate (compound represented by the above structural formula (a-1)) 6.0 parts (10.0% by mass) Methyl methacrylate 54.0 parts Polymerization initiator: Azoisobutyronitrile (AIBN) 1.5 parts The above materials were mixed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Other than that, Resin A12 was produced in the same manner as in the production example of Resin A1.

[0153] Table 1 shows the content of the monomer unit represented by formula (II) in resins A1 to A12. [Table 1]

[0154] (Production Example of Crystalline Polyester Resin C) Dodecanedioic acid 50 parts by mole 1,6-Hexanediol 50 parts by mole Octadecanoic acid 5 mole parts The raw material monomers and tin(II) octylate (0.5 parts per 100 parts of the total amount of raw material monomers) were placed in a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen inlet tube, and a thermocouple. The temperature was gradually raised to 160°C while stirring under a nitrogen gas atmosphere, and the reaction was carried out at 160°C for 5 hours while stirring. Thereafter, the pressure in the reaction vessel was reduced to 8.3 kPa, and the temperature was raised to 200°C and reacted for 4 hours (first reaction step). After that, the pressure in the reaction vessel was gradually released to return to normal pressure, and then 5.0 mol parts of dodecanoic acid were added per 100 mol parts of the total amount of the raw carboxylic acid component and alcohol component, and reacted at 200°C under normal pressure for 2 hours. Thereafter, the pressure in the reaction vessel was reduced to 5 kPa or less again, and the reaction was carried out at 200°C for 3 hours to obtain a crystalline polyester resin C (second reaction step).

[0155] (Production Example of Amorphous Polyester Resin D) After replacing the atmosphere in a 5L four-neck flask equipped with a nitrogen inlet tube, a cooling tube, a stirrer, and a thermocouple with nitrogen, the raw materials and tin(II) octylate shown in Table 2 were added, and the mixture was heated to 180°C and reacted for 10 hours. After further reacting for 5 hours at 15 mmHg (first reaction step), trimellitic anhydride was added according to Table 4 as the second reaction step, and the mixture was reacted at 180°C for 3 hours to obtain amorphous polyester resin D.

[0156] (Production Example of Amorphous Polyester Resin E) Amorphous polyester resin E was produced in the same manner as in the production example of amorphous polyester resin D, except that the raw materials shown in Table 2 were used and the reaction was stopped in the second reaction step when it was confirmed that the softening point had reached the temperature shown in Table 2.

[0157] [Table 2] In Table 2, the abbreviations have the following meanings: BPA-PO: Propylene oxide adduct of bisphenol A BPA-EO: Ethylene oxide adduct of bisphenol A TPA: Terephthalic acid TMA anhydride: Trimellitic anhydride

[0158] (Production Example of Resin A1 Dispersion) Toluene (Wako Pure Chemical Industries, Ltd.) 300 parts 100 parts of resin A1 The above materials were weighed, mixed, and dissolved at 90°C. Separately, 2.0 parts of sodium dodecylbenzenesulfonate and 4.0 parts of sodium laurate were added to 700 parts of ion-exchanged water and dissolved by heating at 90°C. The toluene solution and the aqueous solution were then mixed and stirred at 7000 rpm using an ultra-high speed stirring device TK Robomix (manufactured by Primix). Furthermore, the mixture was emulsified at a pressure of 200 MPa using a high-pressure impact dispersing machine Nanomizer (manufactured by Yoshida Kikai Kogyo). After that, the toluene was removed using an evaporator, and the concentration was adjusted with ion-exchanged water to obtain an aqueous dispersion (resin A1 dispersion) with a concentration of 20% by mass.

[0159] (Production Examples of Resin A2 Dispersion to Resin A12 Dispersion) In the production example of the resin A1 dispersion, resins A2 to A12 were used instead of resin A1. Other than that, Resin A2 dispersions to Resin A12 dispersions were produced in the same manner as in the production example of Resin A1 dispersion.

[0160] (Production example of resin B) Xylene 100.0 parts Styrene 100.0 parts n-Butyl acrylate 10.0 parts Acrylic acid 1.5 parts Dodecanethiol 6.0 parts Carbon tetrabromide 1.0 parts The above materials were put into a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. The reaction vessel was heated to 185°C while stirring at 200 rpm to carry out a polymerization reaction for 10 hours. The solvent was then removed, and the mixture was vacuum dried at 40°C for 24 hours to obtain Resin B.

[0161] (Example of resin B dispersion production) Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.) 300 parts ·Resin B 100 parts Anionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 0.5 parts The above materials were weighed, mixed, and dissolved. Next, 20.0 parts of 1 mol / L ammonia water was added and stirred at 4000 rpm using an ultra-high speed stirring device TK Robomix (manufactured by Primix). Furthermore, 700 parts of ion-exchanged water was added at a rate of 8 g / min to precipitate resin B. Then, tetrahydrofuran was removed using an evaporator, and the concentration was adjusted with ion-exchanged water to obtain an aqueous dispersion of resin B (resin B dispersion) with a concentration of 20% by mass.

[0162] (Production Example of Crystalline Polyester Resin C Dispersion) Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.) 300 parts Crystalline resin Polyester resin C 100 parts Anionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 0.5 parts The above materials were weighed, mixed, and dissolved. Next, 20.0 parts of 1 mol / L ammonia water was added and stirred at 4000 rpm using an ultra-high speed stirring device TK Robomix (manufactured by Primix). Furthermore, 700 parts of ion-exchanged water was added at a rate of 8 g / min to precipitate crystalline polyester resin C. Then, tetrahydrofuran was removed using an evaporator, and the concentration was adjusted with ion-exchanged water to obtain an aqueous dispersion of crystalline polyester resin C (crystalline polyester resin C dispersion) with a concentration of 20% by mass.

[0163] (Production Example of Amorphous Polyester Resin D Dispersion) Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.) 300 parts Amorphous polyester resin D 100 parts Anionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 0.5 parts The above materials were weighed, mixed, and dissolved. Next, 20.0 parts of 1 mol / L ammonia water was added and stirred at 4000 rpm using an ultra-high speed stirring device TK Robomix (manufactured by Primix). Furthermore, 700 parts of ion-exchanged water was added at a rate of 8 g / min to precipitate amorphous polyester resin D. Thereafter, tetrahydrofuran was removed using an evaporator, and the concentration was adjusted with ion-exchanged water to obtain an aqueous dispersion of amorphous polyester resin D (amorphous polyester resin D dispersion) with a concentration of 20% by mass.

[0164] (Production Example of Amorphous Polyester Resin E Dispersion) Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.) 300 parts Amorphous polyester resin E 100 parts Anionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 0.5 parts The above materials were weighed, mixed, and dissolved. Next, 20.0 parts of 1 mol / L ammonia water was added and stirred at 4000 rpm using an ultra-high speed stirring device TK Robomix (manufactured by Primix). Furthermore, 700 parts of ion-exchanged water was added at a rate of 8 g / min to precipitate amorphous polyester resin E. Then, tetrahydrofuran was removed using an evaporator, and the concentration was adjusted with ion-exchanged water to obtain an aqueous dispersion of amorphous polyester resin E (amorphous polyester resin E dispersion) with a concentration of 20% by mass.

[0165] (Production Example of Release Agent Microparticle Dispersion) Aliphatic hydrocarbon compound HNP-51 (manufactured by Nippon Seiro) 120 parts Anionic surfactant Neogen RK (manufactured by Daiichi Kogyo Seiyaku) 6 parts -Ion-exchanged water 400 parts The above materials were weighed and placed in a mixing vessel equipped with a stirrer, then heated to 90°C and circulated through a Clearmix W Motion (M Technique) for 60 minutes to perform dispersion processing. The dispersion processing conditions were as follows: Rotor outer diameter: 3cm Clearance: 0.3mm Rotor speed: 19000 r / min Screen rotation speed: 19000 r / min After the dispersion treatment, the mixture was cooled to 40° C. under the cooling treatment conditions of a rotor rotation speed of 1000 r / min, a screen rotation speed of 0 r / min, and a cooling rate of 10° C. / min, thereby obtaining an aqueous dispersion liquid (release agent dispersion liquid) with a release agent concentration of 20 mass %.

[0166] (Production of colorant particle dispersion) Cyan pigment (Dainichi Seika: Pigment Blue 15:3) 50.0 parts Anionic surfactant Neogen RK (manufactured by Daiichi Kogyo Seiyaku) 7.5 parts 442.5 parts ion-exchanged water The above materials were weighed, mixed, dissolved, and dispersed for approximately 1 hour using a high-pressure impact disperser Nanomizer (manufactured by Yoshida Kikai Kogyo Co., Ltd.) to obtain an aqueous dispersion (colorant particle dispersion) containing dispersed colorant particles with a concentration of 10% by mass.

[0167] (Toner 1 manufacturing example) ·Resin A1 dispersion 500 parts ·Resin B dispersion liquid 120 parts Release agent dispersion 50 parts Colorant microparticle dispersion 80 parts 160 parts deionized water The above materials were put into a round stainless steel flask, mixed, and then 10 parts of 10% magnesium sulfate aqueous solution was added. The mixture was then dispersed for 10 minutes at 5000 r / min using a homogenizer Ultra Turrax T50 (manufactured by IKA). The mixture was then heated to 58°C in a heating water bath using a stirring blade while appropriately adjusting the rotation speed so that the mixture was stirred. The volume average particle size of the formed aggregated particles was appropriately confirmed using a Coulter Multisizer III, and when aggregated particles with a volume average particle size of about 6.00 μm were formed, 100 parts of sodium ethylenediaminetetraacetate was added, and the mixture was heated to 75° C. while continuing to stir. The mixture was then held at 75° C. for 1 hour to fuse the aggregated particles. Thereafter, the mixture was cooled to 50° C. and held at that temperature for 1 hour to promote crystallization of the polymer. After that, the mixture was cooled to 25° C., filtered, separated into solid and liquid, and washed with ion-exchanged water. After washing, the mixture was dried using a vacuum dryer to obtain toner particles 1 having a weight average particle size (D4) of about 6.05 μm.

[0168] Next, mix the following materials in a Henschel mixer FM-10C (manufactured by Mitsui Miike Chemical Industry) at a rotation speed of 30 s. -1 The mixture was mixed at 10 minutes rotation time to obtain toner 1. 100 parts of toner particles 3 parts of silica particles with an average particle size of 130 nm and surface-treated with hexamethyldisilazane 1 part of silica particles with an average particle size of 20 nm and surface-treated with hexamethyldisilazane Toner 1 had a weight average particle size (D4) of 6.1 μm and an average circularity of 0.975.

[0169] (Production Examples of Toner 2 to Toner 12) In the production example of toner 1, resin A2 dispersion liquid to resin A12 dispersion liquid were used instead of resin A1 dispersion liquid. Other than that, in the same manner as in the production example of toner 1, toners 2 to 12 were produced.

[0170] (Toner 13 manufacturing example) In the production example of toner 1, 100 parts of sodium ethylenediaminetetraacetate was added, and then the mixture was heated to 75° C. while continuing to stir. The mixture was then held at 75° C. for 1 hour to fuse the aggregated particles. Thereafter, the mixture was cooled to 50° C. and held at that temperature for 3 hours to promote crystallization of the polymer. Except for the above, toner 13 was produced in the same manner as in the production example of toner 1.

[0171] (Toner 14 manufacturing example) Toner 14 was produced in the same manner as in Production Example of Toner 1, except that the materials in Production Example of Toner 1 were changed as follows. Crystalline polyester resin C dispersion 75 parts Amorphous polyester resin D dispersion 300 parts Amorphous polyester resin E dispersion 150 parts Release agent dispersion 50 parts Colorant microparticle dispersion 80 parts 160 parts deionized water Table 3 shows the weight average particle size (D4), average circularity and softening point (Tm) of toner 1 to toner 14. [Table 3]

[0172] (Magnetic carrier manufacturing example) Number average particle size: 0.30μm, magnetization strength under a magnetic field of (1000 / 4π(kA / m): 65Am 2 / kg) of magnetite 1 Number average particle size: 0.50μm, magnetization strength under a magnetic field of (1000 / 4π(kA / m): 65Am 2 / kg) of magnetite 2 To 100 parts of each of the above materials, 4.0 parts of a silane compound (3-(2-aminoethylaminopropyl)trimethoxysilane) was added, and the mixture was mixed and stirred at high speed in a container at 100° C. or higher to treat each of the fine particles. Phenol: 10% by weight Formaldehyde solution: 6% by weight (Formaldehyde 40% by mass, methanol 10% by mass, water 50% by mass) Magnetite treated with the above silane compound 1: 58% by mass Magnetite 2 treated with the above silane compound: 26% by mass 100 parts of the above material, 5 parts of a 28% by mass aqueous ammonia solution, and 20 parts of water were placed in a flask, and the temperature was raised to 85°C over 30 minutes while stirring and mixing, and the temperature was maintained for 3 hours to cause a polymerization reaction and harden the resulting phenolic resin. The hardened phenolic resin was then cooled to 30°C, and water was added, after which the supernatant liquid was removed, and the precipitate was washed with water and then air-dried. This was then dried under reduced pressure (5mmHg or less) at a temperature of 60°C to obtain spherical magnetic carrier 1 with magnetic material dispersion. The 50% particle diameter (D50) based on volume of magnetic carrier 1 was 34.21μm.

[0173] <Production example of two-component developer 1> 92.0 parts of magnetic carrier 1 and 8.0 parts of toner 1 were mixed in a V-type mixer (V-20, manufactured by Seishin Enterprise Co., Ltd.) to obtain two-component developer 1.

[0174] <Production Examples of Two-Component Developers 2 to 14> In the production example of the two-component developer 1, toner 2 to toner 14 were used instead of toner 1, respectively. Other than that, two-component developer 2 to two-component developer 14 were produced in the same manner as in the production example of two-component developer 1.

[0175] Example 1 [Evaluation: Measurement of crystallinity of crystalline resin in two-component developer] The crystallinity of Resin A1 in Two-Component Developer Resin 1 was determined by the above-mentioned method for measuring the crystallinity of resins. The results are shown in Table 4.

[0176] [Evaluation: Toner slip-through evaluation] The electrophotographic photoreceptor 1 thus prepared was mounted on a modified electrophotographic copier iR-ADV C5560F III manufactured by Canon Inc., and a toner slip-through evaluation was performed. The electrophotographic photoreceptor was mounted in a drum cartridge for the electrophotographic copier iR-ADV C5560F III (from which the charging roller cleaning brush was removed for the toner slip-through evaluation) such that the top end of the electrophotographic photoreceptor coating was located at the rear side of the modified electrophotographic copier iR-ADV C5560F III. An example of the state in which the electrophotographic photoreceptor and the cleaning blade come into contact is shown in Fig. 2. The cleaning blade 13 used was the same as that attached to the drum cartridge for the electrophotographic copier iR-ADV C5560F III (hardness: 80 JISA°, resilience at 25°C: 35%). The cleaning blade 13 has a blade undersurface 132 and a blade front surface 131, and the contact angle (narrow angle) between the electrophotographic photoreceptor 1 and the blade undersurface 132 of the cleaning blade 13 was set to 25°, and the contact pressure with the electrophotographic photoreceptor was set to 40 N / m. The prepared two-component developer 1 for evaluation was set in the developing device of the cyan station of the evaluation machine. A mechanism for supplying a lubricant onto the surface of the electrophotographic photoreceptor was added upstream of the cleaning blade.

[0177] The evaluation was performed in a high-temperature, high-humidity environment of 30°C / 80% RH. After continuous image formation on 10,000 sheets with an image ratio of 1%, the toner remaining on the charging roller was taped onto a blank sheet of paper, and the density difference with the blank sheet was measured using a densitometer (product name: 504 Spectrodensitometer; manufactured by X-Rite Inc.), and the evaluation was performed according to the following criteria. A was the best rank, and D was the worst rank. A: The difference in density between the toner remaining on the charging roller and white paper is less than 0.03 (excellent). B: The difference in density between the toner remaining on the charging roller and white paper is 0.03 to less than 0.06 (slightly better). C: The difference in density between the toner remaining on the charging roller and the white paper is 0.06 or more and less than 0.10 (the acceptable level in this invention). D: The difference in density between the toner remaining on the charging roller and the white paper is 0.10 or more (a level that is unacceptable in the present invention).

[0178] [Example 2~ 6 , 11~12、 Comparative Examples 1 to 4 Example 2 6 , 11~12、 As Comparative Examples 1 to 4, image evaluation was performed in the same manner as in Example 1 for the combinations of electrophotographic photoreceptors and two-component developers shown in Table 4. In Comparative Example 4, the crystallinity of crystalline polyester resin C was measured. The evaluation results are shown in Table 4.

[0179] [Table 4] [Explanation of symbols]

[0180] 1. Electrophotographic photoreceptor 2-axis 3. Charging means 4 Exposure light 5. Developing method 6 Transfer Method 7 Transfer material 8 Fixing Method 9 Cleaning Method 10 Pre-exposure light 11 Process cartridge 12 Guidance means 13 Cleaning blade

Claims

1. An electrophotographic photoreceptor; A charging means for charging the surface of the electrophotographic photoreceptor; an image exposure means for irradiating an image exposure light onto the charged surface of the electrophotographic photoreceptor to form an electrostatic latent image on the surface of the electrophotographic photoreceptor; a developing means having a toner and developing the electrostatic latent image with the toner to form a toner image on the surface of the electrophotographic photoreceptor; a transfer means for transferring the toner image from the surface of the electrophotographic photoreceptor to a transfer material; a cleaning means for removing residual toner remaining on the surface of the electrophotographic photoreceptor after transfer by the transfer means, using a cleaning blade; a fixing means for fixing the toner image transferred onto the transfer material, The surface layer of the electrophotographic photoreceptor is a polymerized film of a composition containing at least one compound selected from the group consisting of compounds having a guanamine structure and compounds having a melamine structure, and two or more kinds of charge transporting materials having a structure represented by the following general formula (I): 【Chemistry 1】 In general formula (I), Ar １ ~Ar ４ may be the same or different, and each independently represents a substituted or unsubstituted aryl group; Ar ５ represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' １ -X)n １ R' ２ -Y, each c independently represents 0 or 1, k represents 0 or 1, and the total number of Ds is 2 to 4; Here, R' １ and R' ２ each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; １ represents 0 or 1, X represents an oxygen atom, an NH atom, or a sulfur atom, and Y represents -OH; However, two or more kinds of charge transporting materials having a structure represented by general formula (I) have two or more —OH groups represented by Y, and at least one kind of charge transporting material has four —OH groups represented by Y; The toner in the developing means has toner particles containing a resin A having a unit represented by the following general formula (II), The resin A is a crystalline resin, The content of the unit represented by the following general formula (II) in the resin A is 30.0 mass % to 100.0 mass %: 【Chemistry 2】 (In general formula (II), R Ｚ１ represents a hydrogen atom or a methyl group, R Ｚ２ represents an alkyl group having 18 to 36 carbon atoms. Electrophotographic apparatus characterized in that

2. 2. The electrophotographic apparatus according to claim 1, wherein the resin A has a crystallinity of 30% to 70%.

3. 3. The electrophotographic apparatus according to claim 1, wherein the resin A further contains a unit represented by the following formula (III) or general formula (IV): 【Chemistry 3】 【Chemistry 4】 In formula (IV), R Ｚ３ represents a hydrogen atom or a methyl group.

4. 4. The electrophotographic apparatus according to claim 1, wherein the surface layer of the electrophotographic photoreceptor contains a binder resin.

5. 4. The electrophotographic apparatus according to claim 1, wherein the surface layer of the electrophotographic photoreceptor contains an amide resin, a butyral resin, or a polyvinyl butyral resin.

6. An electrophotographic device according to claim 1, wherein a surface layer of the electrophotographic photosensitive member contains a polyvinyl butyral resin.

7. 7. A process cartridge which integrally supports the electrophotographic photosensitive member according to claim 1 and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, a discharging means and a cleaning means, and is detachably mountable to a main body of an electrophotographic apparatus.

8. a charging step of charging the surface of an electrophotographic photoreceptor; an image exposure step of irradiating the charged surface of the electrophotographic photoreceptor with image exposure light to form an electrostatic latent image on the surface of the electrophotographic photoreceptor; a developing step of developing the electrostatic latent image with a toner to form a toner image on the surface of the electrophotographic photoreceptor; a transfer step of transferring the toner image from the surface of the electrophotographic photoreceptor to a transfer material; a cleaning step of removing residual toner remaining on the surface of the electrophotographic photoreceptor after the transfer step by using a cleaning blade; a fixing step of fixing the toner image transferred onto the transfer material; An image forming method comprising: The surface layer of the electrophotographic photoreceptor is A polymerized film of a composition comprising at least one compound selected from the group consisting of a compound having a guanamine structure and a compound having a melamine structure, and two or more charge transport materials having a structure represented by the following general formula (I): 【Chemistry 5】 In general formula (I), Ar １ ~Ar ４ may be the same or different, and each independently represents a substituted or unsubstituted aryl group; Ar ５ represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group, and D represents -(-R' １ -X)n １ R' ２ each c is independently 0 or 1; k is 0 or 1; and the total number of D is 2 to 4; １ and R' ２ each independently represents a linear or branched alkylene group having 1 to 5 carbon atoms; １ represents 0 or 1, X represents an oxygen atom, an NH atom, or a sulfur atom, and Y represents -OH; However, two or more kinds of charge transporting materials having a structure represented by the general formula (I) have two or more —OH groups represented by Y, and at least one kind of charge transporting material has four —OH groups represented by Y, The toner has toner particles containing a resin A having a unit represented by the following general formula (II), The resin A is a crystalline resin, The content of the unit represented by the general formula (II) in the resin A is 30.0% by mass to 100.0% by mass. 【Chemistry 6】 (In general formula (II), R Ｚ１ represents a hydrogen atom or a methyl group, R Ｚ２ represents an alkyl group having 18 to 36 carbon atoms.

1. An image forming method comprising:

Images