Process cartridge and electrophotographic apparatus

Abstract

To provide a process cartridge that improves transfer properties during repeated use in a high temperature and high humidity environment.SOLUTION: A process cartridge is removably attached to a main body of an electrophotographic device. The process cartridge has an electrophotographic photoreceptor, toner, and a developing member that supplies the toner to the electrophotographic photoreceptor. The electrophotographic photoreceptor has a surface layer containing a (meth)acrylic resin having a urethane structure. The toner has toner particles and hydrotalcite particles as an external additive. In filter fitting analysis in STEM-EDS analysis, the hydrotalcite particles contain fluorine.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a process cartridge having an electrophotographic photosensitive member and an electrophotographic apparatus. [Background technology]

[0002] In recent years, electrophotographic devices have been required to be smaller and less expensive, while at the same time being longer in life and faster in speed. However, in the electrophotographic process, longer life and faster speeds tend to cause various problems, and adding components and control units to address these problems tends to increase the size of the electrophotographic device and its cost. Therefore, in order to achieve both longer life and faster speeds and smaller size and lower costs, various efforts have been made to address these problems.

[0003] Among the above-mentioned problems is the transferability problem in which toner remains on the electrophotographic photosensitive member when a toner image formed on the electrophotographic photosensitive member (hereinafter also referred to as "photosensitive member") is transferred to a transfer material in a transfer process. If the transferability is poor, a large amount of residual toner remains on the electrophotographic photosensitive member after the transfer process, which hinders the miniaturization of waste toner containers for collecting the residual toner. Therefore, there is a demand for a process cartridge with improved transferability.

[0004] Patent Document 1 describes a toner containing a polyester resin and a layered inorganic mineral having a fluorine compound on its surface and having the interlayer space modified with organic ions. Surface-treating the layered inorganic mineral, which is often present on the toner surface, with a fluorine compound allows the highly polar fluorine compound to be efficiently present on the toner surface, and the fluorine compound is firmly fixed to the toner surface, thereby imparting high chargeability and charge stability. Furthermore, by modifying the interlayer space of the layered inorganic mineral with organic ions to impart appropriate hydrophobicity, a large amount of the layered inorganic mineral is present near the surface of the toner particles during toner granulation in an aqueous medium. Even with a very small amount of layered inorganic mineral added, the toner exhibits irregular shape and charge adjustment functions, thereby improving low-temperature fixability, which can be a problem when a large amount of layered inorganic mineral is added.

[0005] Patent Document 2 describes a toner containing an amorphous polyester resin, an addition polymerization resin, and a wax, in which the solubility parameters of the three components satisfy a certain relationship. By designing the toner so that the solubility parameters satisfy a certain relationship, the amorphous polyester resin and the addition polymerization resin form a sea-island phase separation structure, and a structure can be achieved in which the wax is encapsulated within the island-like addition polymerization resin. This reduces the amount of wax exposed on the toner surface, thereby achieving improved transferability, durability, and other properties.

[0006] Patent Document 3 describes an electrophotographic photoreceptor in which a surface layer is formed by curing a urethane acrylate having six or more radically polymerizable functional groups and a charge transport material having four radically polymerizable functional groups within a certain blending ratio. By adjusting the contents of the urethane acrylate having six or more radically polymerizable functional groups and the charge transport material having four radically polymerizable functional groups, it is possible to improve the crosslinking density of the crosslinked film while satisfying the electrical properties required of the electrophotographic photoreceptor, and therefore to achieve good abrasion resistance without impairing the electrical properties. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2017-125892 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-64807 [Patent Document 3] U.S. Patent Application No. 2017 / 184987 Summary of the Invention [Problem to be solved by the invention]

[0008] According to the investigations of the present inventors, in all of the technologies described in Patent Documents 1 to 3, the toner and photoreceptor were insufficiently designed, and therefore transferability was sometimes insufficient when repeatedly used under high temperature and high humidity conditions, and these technologies still had an unresolved problem.

[0009] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a process cartridge that improves transferability when repeatedly used in a high-temperature, high-humidity environment. [Means for solving the problem]

[0010] The above object is achieved by the present invention as follows: That is, the process cartridge according to the present invention is a process cartridge detachably mountable to the main body of an electrophotographic apparatus, the process cartridge having an electrophotographic photosensitive member, toner, and a developing member that supplies the toner to the electrophotographic photosensitive member, the electrophotographic photosensitive member having a surface layer containing a (meth)acrylic resin having a urethane structure, the toner having toner particles and hydrotalcite particles as an external additive, and the hydrotalcite particles containing fluorine in a filter fitting analysis in a STEM-EDS analysis. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a process cartridge that improves transferability when repeatedly used in a high-temperature, high-humidity environment. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic view showing an example of an electrophotographic apparatus having a process cartridge including an electrophotographic photosensitive member, toner, and a developing member. [Figure 2] (a): Schematic diagram of line analysis in STEM-EDS analysis. (b): An example of X-ray intensities of fluorine and aluminum obtained by line analysis. (c): Another example of X-ray intensities of fluorine and aluminum obtained by line analysis. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention will be described in detail below with reference to preferred embodiments. The present invention provides a process cartridge that is detachably mountable to a main body of an electrophotographic apparatus, The process cartridge comprises an electrophotographic photosensitive member, toner, and a developing member that supplies the toner to the electrophotographic photosensitive member, the electrophotographic photosensitive member having a surface layer that contains a (meth)acrylic resin having a urethane structure, the toner having toner particles and hydrotalcite particles as an external additive, and filter fitting analysis in a STEM-EDS analysis reveals that the hydrotalcite particles contain fluorine. The present invention also relates to an electrophotographic apparatus having the above process cartridge.

[0014] The inventors have conducted research and found that in the prior art, the transferability may be insufficient when used repeatedly under high temperature and high humidity conditions due to insufficient design of the toner and photoreceptor.

[0015] Therefore, the present inventors have optimized the design combination of the photoreceptor and the toner, and have found that the above-mentioned problem can be solved by having the photoreceptor have a surface layer containing a (meth)acrylic resin having a urethane structure, the toner have toner particles and hydrotalcite particles as an external additive, and in a filter fitting analysis in a STEM-EDS analysis, the hydrotalcite particles contain fluorine.

[0016] The present inventors believe that the mechanism by which the above-mentioned problems can be solved with such a configuration is as follows.

[0017] The hydrotalcite particles contained in the toner as an external additive have a strong positive charge property, so that the hydrotalcite particles are positively charged on the developing member that supplies the toner to the photoreceptor, i.e., the developing roller, while the toner particles are negatively charged, resulting in an electrostatic attraction between the hydrotalcite particles and the toner particles.

[0018] When toner is subjected to friction at the contact area between the photoreceptor and the developing roller, the fluorine-containing hydrotalcite particles are positioned more negatively than the (meth)acrylic resin in the photoreceptor surface layer in the triboelectric series, weakening the positive charge of the fluorine-containing hydrotalcite particles relative to the strong positive charge of the hydrotalcite particles. This weakens the electrostatic attraction between the hydrotalcite particles and the toner particles, allowing the hydrotalcite particles to migrate to the photoreceptor surface. The photoreceptor surface layer, which contains a resin with a urethane structure, has excellent elasticity, increasing the friction experienced by the toner at the contact area between the photoreceptor and the developing roller. This further weakens the positive charge of the hydrotalcite particles, allowing a sufficient amount of hydrotalcite particles to migrate to the photoreceptor surface. Furthermore, the inclusion of fluorine in the layered compound hydrotalcite particles allows slippage between the hydrotalcite particle layers when toner is subjected to friction at the contact area between the photoreceptor and the developing roller, further increasing the friction.

[0019] When photoreceptors are repeatedly used in high-temperature, high-humidity environments, hydrophilic discharge products accumulate on the photoreceptor surface, and moisture in the environment causes liquid bridges to form between the discharge products on the photoreceptor surface and the toner. This is thought to increase the adhesive force between the photoreceptor surface and the toner, resulting in poor transferability to the transfer material. However, hydrotalcite particles that migrate from the toner to the photoreceptor surface can incorporate anionic discharge products such as NOx between their layers through ion exchange, reducing the formation of liquid bridges between the discharge products on the photoreceptor surface and the toner, thereby reducing the adhesive force between the photoreceptor surface and the toner, improving transferability to the transfer material.

[0020] Alternatively, by incorporating the hydrotalcite particles into the toner rather than the photoreceptor, the hydrotalcite particles can be continuously supplied to the surface of the photoreceptor, and the above-mentioned effect can be maintained even during repeated use.

[0021] As explained above, the photoreceptor and the toner exert a synergistic effect on each other, which makes it possible to achieve the effect of the present invention, that is, to improve transferability during repeated use in a high-temperature, high-humidity environment.

[0022] [Electrophotographic photoreceptor] The electrophotographic photoreceptor according to the present invention is characterized by having a surface layer. The method for producing the electrophotographic photoreceptor according to the present invention includes a method in which a coating liquid for each layer described below is prepared, and the coating liquid for the desired layer is applied in 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 viewpoints of efficiency and productivity. The support and each layer will be described below.

[0023] <Support> In the present invention, the electrophotographic photoreceptor has a support. In the present invention, the support is preferably a conductive support having electrical conductivity. The shape of the support may be cylindrical, belt-like, sheet-like, or the like. Of these, a cylindrical support is preferred. The surface of the support may be subjected to electrochemical treatment such as anodization, blasting, cutting, or the like. The support is preferably made of a metal, a resin, or a glass. Examples of metals include aluminum, iron, nickel, copper, gold, stainless steel, and alloys thereof. Among these, aluminum is preferred. That is, a preferred example of the support is an aluminum support. Furthermore, the resin or glass may be made conductive by mixing or coating it with a conductive material.

[0024] <Conductive layer> In the electrophotographic photoreceptor according to the present invention, a conductive layer may be provided on the support, which can conceal scratches and irregularities on the support surface and control light reflection on the support surface. The conductive layer preferably contains conductive particles and a resin.

[0025] Examples of materials for the conductive particles include metal oxides, metals, and carbon black. Examples of metal oxides include zinc oxide, aluminum oxide, indium oxide, silicon oxide, zirconium oxide, tin oxide, titanium oxide, 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 metal oxides are used as conductive particles, the surfaces of the metal oxides may be treated with a silane coupling agent or the like, or the metal oxides may be doped with elements such as phosphorus or aluminum or their oxides, such as phosphorus, aluminum, niobium, and tantalum. The conductive particles may have a laminated structure including a core particle and a coating layer covering the core particle. Examples of the core particle include titanium oxide, barium sulfate, and zinc oxide. Examples of the coating layer include metal oxides such as tin oxide and titanium oxide. When metal oxide particles are used as the conductive particles, the volume average particle size thereof is preferably 1 nm or more and 500 nm or less, and more preferably 3 nm or more and 400 nm or less.

[0026] 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.

[0027] The average thickness of the conductive layer is preferably 1 μm or more and 50 μm or less, and particularly preferably 3 μm or more and 40 μm or less.

[0028] 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 from this, and drying it. Examples of solvents 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 dispersion methods for dispersing the conductive particles in the coating solution for the conductive layer include methods using a paint shaker, sand mill, ball mill, or liquid collision-type high-speed disperser.

[0029] <Undercoat layer> In the electrophotographic photoreceptor according to the present invention, an undercoat layer may be provided on the support or the conductive layer. By providing the undercoat layer, the adhesion between layers can be improved and a charge injection blocking function can be imparted.

[0030] 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.

[0031] Examples of the resin include polyester resin, polycarbonate resin, polyvinyl acetal resin, acrylic resin, epoxy resin, melamine resin, polyurethane resin, phenol resin, polyvinylphenol resin, alkyd resin, polyvinyl alcohol resin, polyethylene oxide resin, polypropylene oxide resin, polyamide resin, polyamic acid resin, polyimide resin, polyamideimide resin, and cellulose resin.

[0032] Examples of the polymerizable functional group possessed by 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.

[0033] Furthermore, for the purpose of improving electrical properties, the undercoat layer may further contain an electron transporting substance, a metal oxide, a metal, a conductive polymer, etc. Among these, it is preferable to use an electron transporting substance 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 above-mentioned monomer having the polymerizable functional group. Examples of metal oxides include indium tin oxide, tin oxide, indium oxide, titanium oxide, zinc oxide, aluminum oxide, silicon dioxide, etc. Examples of metals include gold, silver, aluminum, etc. The undercoat layer may further contain an additive.

[0034] The average thickness of the undercoat layer is preferably from 0.1 μm to 50 μm, more preferably from 0.2 μm to 40 μm, and particularly preferably from 0.3 μm to 30 μm.

[0035] 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 film. 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.

[0036] <Photosensitive layer> The photosensitive layer of the electrophotographic photoreceptor according to the present invention 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 containing both a charge generation material and a charge transport material.

[0037] (1) Laminated photosensitive layer The laminated photosensitive layer has a charge generating layer and a charge transport layer.

[0038] (1-1) Charge generation layer The charge generating layer preferably contains a charge generating material and a resin.

[0039] Examples of charge-generating materials 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 40% by mass or more and 85% by mass or less, and more preferably 60% by mass or more and 80% by mass or less, based on the total mass of the charge generating layer.

[0040] 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 preferred.

[0041] The charge generating layer may further contain additives such as antioxidants and ultraviolet absorbers, etc. Specific examples include hindered phenol compounds, hindered amine compounds, sulfur compounds, phosphorus compounds, and benzophenone compounds.

[0042] The average thickness of the charge generating layer is preferably from 0.1 μm to 1 μm, and more preferably from 0.15 μm to 0.4 μm.

[0043] 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 from the coating solution, and drying the coating film. 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.

[0044] (1-2) Charge transport layer The charge transport layer preferably contains a charge transport material and a resin.

[0045] 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. The content of the charge transport material in the charge transport layer is preferably 25% by mass to 70% by mass, and more preferably 30% by mass to 55% by mass, based on the total mass of the charge transport layer.

[0046] Examples of the resin include polyester resin, polycarbonate resin, (meth)acrylic resin, polystyrene resin, etc. Among these, polycarbonate resin, polyester resin, and (meth)acrylic resin are preferred. As the polyester resin, polyarylate resin is particularly preferred. The content ratio (mass ratio) of the charge transport material to the resin is preferably 4:10 to 20:10, and more preferably 5:10 to 12:10.

[0047] The charge transport layer may also 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.

[0048] The average thickness of the charge transport layer is preferably from 5 μm to 50 μm, more preferably from 8 μm to 40 μm, and particularly preferably from 10 μm to 30 μm.

[0049] 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 from the coating solution, and drying the coating film. 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 and aromatic hydrocarbon-based solvents are preferred.

[0050] (2) Single-layer photosensitive layer The single-layer 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 the coating film on a support, and drying the coating film. The charge generating material, charge transporting material, and resin are the same as those exemplified in "(1) Multilayer Photosensitive Layer" above.

[0051] <Protective layer> In the electrophotographic photoreceptor according to the present invention, a protective layer may be provided on the photosensitive layer, which can improve durability.

[0052] The protective layer is provided for the purpose of providing durability for a long life, and may be, for example, a high-strength layer containing a resin, and does not necessarily need to contain conductive particles or a charge transport material to improve charge transport performance. However, from the viewpoint of improving the basic electrical properties of the photoreceptor, it is preferable to contain conductive particles and / or a charge transport material and a resin to achieve both durability and basic electrical properties.

[0053] Examples of conductive particles include particles of metal oxides such as titanium oxide, zinc oxide, tin oxide, and indium oxide.

[0054] 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.

[0055] Examples of the resin include polyester resin, acrylic resin, phenoxy resin, polycarbonate resin, polystyrene resin, phenol resin, melamine resin, epoxy resin, etc. Among these, polycarbonate resin, polyester resin, and acrylic resin are preferred.

[0056] The protective layer may also be formed as a cured film by polymerizing a composition containing a monomer having a polymerizable functional group. Examples of the reaction include thermal polymerization, photopolymerization, and radiation-induced polymerization. Examples of the polymerizable functional group possessed by the monomer having a polymerizable functional group include an acryloyl group and a methacryloyl group. A material having charge transport capability may also be used as the monomer having a polymerizable functional group.

[0057] The protective layer may 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.

[0058] The average thickness of the protective layer is preferably 0.5 μm or more and 10 μm or less, and more preferably 1 μm or more and 7 μm or less.

[0059] The protective layer can be formed by preparing a coating solution for the protective layer containing the above-mentioned materials and solvent, forming the coating film on the photosensitive layer, and drying and / or curing the coating film. 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.

[0060] <Surface layer> In the electrophotographic photoreceptor according to the present invention, the surface layer contains a (meth)acrylic resin having a urethane structure. The urethane structure refers to a -NHC(=O)O- structure.

[0061] The surface layer referred to here is a portion of the photoreceptor that comes into contact with toner and various members during the electrophotographic process. Of the layers constituting the photoreceptor, the surface layer can be a protective layer, a charge transport layer, a single-layer photosensitive layer, or a charge generation layer, but from the viewpoint of achieving both durability and basic electrical properties in the electrophotographic process, the surface layer is preferably a protective layer or a charge transport layer, and more preferably a protective layer.

[0062] The elastic deformation rate of the surface layer is preferably 45% or more. By setting the elastic deformation rate of the surface layer to 45% or more, a certain level of elasticity is imparted to the surface layer, increasing the friction that the toner experiences at the contact portion between the photosensitive member and the developing roller, and accelerating the migration of the hydrotalcite particles contained in the toner to the surface of the photosensitive member.

[0063] The surface layer is preferably formed as a cured film by polymerizing a composition containing a monomer having a polymerizable functional group. Examples of the reaction include thermal polymerization, photopolymerization, and radiation polymerization. Examples of the polymerizable functional group possessed by the monomer having a polymerizable functional group include an acryloyl group and a methacryloyl group. A material having charge transport capability may be used as the monomer having a polymerizable functional group.

[0064] Examples of the monomer having a polymerizable functional group include the following general formulae (A-1) to (A-3).

[0065] [ka] In general formula (A-1), R1~R 12 At least two of the above are structures represented by the following general formula (U-1), and the remaining substituents are hydrogen atoms or methyl groups.

[0066] [ka] In general formula (A-2), R 21 ~R 26 At least two of the above are structures represented by the following general formula (U-1), and the remaining substituents are hydrogen atoms or methyl groups. [ka] In general formula (U-1), R 31 represents a single bond or a hydrocarbon group which may have a substituent, and Acr represents an acryloyloxy group or methacryloyloxy group which may have a substituent.

[0067] [ka] In the general formula (A-3), Acr represents an acryloyloxy group or a methacryloyloxy group which may have a substituent, and R 41 represents a hydrocarbon group which may have a substituent.

[0068] Further, specific examples of the monomer having a polymerizable functional group (hereinafter also referred to as "OCL monomer") include the following formulae (B-1) to (B-17). [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0069] Furthermore, examples of monomers having a polymerizable functional group and charge transporting ability include those represented by the following general formula (C-1). [ka] In general formula (C-1), R 51 ~R 65represents a (meth)acryloyloxy group which may have a substituent, a hydrogen atom, or a methyl group.

[0070] Further, specific examples of monomers having a polymerizable functional group and charge transporting ability include the following formulae (D-1) to (D-12). [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0071] [toner] The toner according to the present invention is characterized by having toner particles and an external additive. The components constituting the toner and the method for producing the toner will be described below.

[0072] <Toner manufacturing method> A method for producing toner particles will now be described. The toner particles can be produced by known methods, such as a kneading and pulverization method or a wet production method. From the viewpoint of uniform particle size and shape controllability, a wet production method is preferably used. Further, the wet production method includes a suspension polymerization method, a dissolution suspension method, an emulsion polymerization aggregation method, an emulsion aggregation method, etc., and an emulsion aggregation method is preferably used.

[0073] In the emulsion aggregation method, materials such as binder resin particles and colorant particles are first dispersed and mixed in an aqueous medium containing a dispersion stabilizer. A surfactant may be added to the aqueous medium. An aggregating agent is then added to aggregate the particles to the desired toner particle size, and then, or simultaneously with the aggregation, the resin particles are fused together. If necessary, the shape is controlled by heat to form toner particles.

[0074] The binder resin particles may be composite particles formed of two or more layers of resins with different compositions, which may be produced by, for example, emulsion polymerization, mini-emulsion polymerization, phase inversion emulsification, or a combination of several methods.

[0075] When an internal additive such as a colorant is contained in the toner particles, the internal additive may be contained in the resin fine particles, or a dispersion liquid of internal additive fine particles consisting only of the internal additive may be separately prepared, and the internal additive fine particles may be aggregated together with the resin fine particles when they are aggregated.

[0076] Furthermore, by adding resin particles with different compositions at different times during aggregation and allowing them to aggregate, it is also possible to produce toner particles with layer structures with different compositions.

[0077] The following can be used as the dispersion stabilizer. Examples of inorganic dispersion stabilizers include tricalcium phosphate, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, and alumina. Examples of organic dispersion stabilizers include polyvinyl alcohol, gelatin, methyl cellulose, methylhydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, and starch.

[0078] As the surfactant, known cationic surfactants, anionic surfactants, and nonionic surfactants can be used. Specific examples of cationic surfactants include dodecylammonium bromide, dodecyltrimethylammonium bromide, dodecylpyridinium chloride, dodecylpyridinium bromide, and hexadecyltrimethylammonium bromide. Specific examples of nonionic surfactants include dodecyl polyoxyethylene ether, hexadecyl polyoxyethylene ether, nonylphenyl polyoxyethylene ether, lauryl polyoxyethylene ether, sorbitan monooleate polyoxyethylene ether, styrylphenyl polyoxyethylene ether, and monodecanoyl sucrose. Specific examples of anionic surfactants include aliphatic soaps such as sodium stearate and sodium laurate, sodium lauryl sulfate, sodium dodecylbenzenesulfonate, and polyoxyethylene (2) lauryl ether sodium sulfate.

[0079] <Binder resin> The binder resin constituting the toner particles will be described. Suitable examples of the binder resin include vinyl resins and polyester resins.

[0080] Examples of the vinyl resin, polyester resin and other binder resin include the following resins or polymers. Homopolymers of styrene and its substituted derivatives such as polystyrene and polyvinyltoluene; styrene-based copolymers such as styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, and styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyamide resin, epoxy resin, polyacrylic resin, rosin, modified rosin, terpene resin, phenolic resin, aliphatic or alicyclic hydrocarbon resin, and aromatic petroleum resin. These binder resins can be used alone or in combination.

[0081] The binder resin preferably contains a carboxy group and is preferably a resin produced using a polymerizable monomer containing a carboxy group, such as vinyl carboxylic acids such as acrylic acid, methacrylic acid, α-ethylacrylic acid, and crotonic acid; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid; and unsaturated dicarboxylic acid monoester derivatives such as succinic acid monoacryloyloxyethyl ester, succinic acid monomethacryloyloxyethyl ester, phthalic acid monoacryloyloxyethyl ester, and phthalic acid monomethacryloyloxyethyl ester.

[0082] The polyester resin may be a condensation polymer of a carboxylic acid component and an alcohol component, as listed below. Examples of the carboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, cyclohexanedicarboxylic acid, and trimellitic acid. Examples of the alcohol component include bisphenol A, hydrogenated bisphenol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane, and pentaerythritol.

[0083] The polyester resin may also be a polyester resin containing a urea group. It is preferred that the carboxyl groups at the terminals of the polyester resin are not capped.

[0084] <Crosslinking agent> In order to control the molecular weight of the binder resin constituting the toner particles, a crosslinking agent may be added during polymerization of the polymerizable monomer. For example, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, divinylbenzene, bis(4-acryloxypolyethoxyphenyl)propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol #200, #400, and #600 diacrylates, dipropylene glycol diacrylate, polypropylene glycol diacrylate, polyester diacrylate (MANDA Nippon Kayaku), and those in which the above acrylates have been replaced with methacrylates.

[0085] The amount of the crosslinking agent added is preferably 0.001 parts by mass or more and 15,000 parts by mass or less relative to 100 parts by mass of the polymerizable monomer.

[0086] <Release agent> It is preferable that the toner particles contain a release agent. In particular, when an ester wax having a melting point of 60° C. or more and 90° C. or less is used, the ester wax has excellent compatibility with the binder resin, and therefore a plasticizing effect is easily obtained.

[0087] Examples of the ester wax include waxes containing fatty acid esters as the main component, such as carnauba wax and montan acid ester wax; and fatty acid esters, such as deacidified carnauba wax, from which some or all of the acid components have been deacidified; methyl ester compounds having a hydroxy group, obtained by, for example, hydrogenating vegetable oils and fats; saturated fatty acid monoesters, such as stearyl stearate and behenyl behenate; diesters of saturated aliphatic dicarboxylic acids and saturated aliphatic alcohols, such as dibehenyl sebacate, distearyl dodecanedioate and distearyl octadecanedioate; and diesters of saturated aliphatic diols and saturated aliphatic monocarboxylic acids, such as nonanediol dibehenate and dodecanediol distearate.

[0088] Among these waxes, it is preferable to use a bifunctional ester wax (diester) having two ester bonds in the molecular structure.

[0089] The difunctional ester wax is an ester compound of a dihydric alcohol and an aliphatic monocarboxylic acid, or an ester compound of a dihydric carboxylic acid and an aliphatic monoalcohol.

[0090] Specific examples of the aliphatic monocarboxylic acid include myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, melissic acid, oleic acid, vaccenic acid, linoleic acid, and linolenic acid.

[0091] Specific examples of the aliphatic monoalcohol include myristyl alcohol, cetanol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, tetracosanol, hexacosanol, octacosanol, and triacontanol.

[0092] Specific examples of dicarboxylic acids include butanedioic acid (succinic acid), pentanedioic acid (glutaric acid), hexanedioic acid (adipic acid), heptanedioic acid (pimelic acid), octanedioic acid (suberic acid), nonanedioic acid (azelaic acid), decanedioic acid (sebacic acid), dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, hexadecanedioic acid, octadecanedioic acid, eicosane dioic acid, phthalic acid, isophthalic acid, and terephthalic acid.

[0093] Specific examples of dihydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,20-eicosanediol, 1,30-triacontanediol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, spiroglycol, 1,4-phenylene glycol, bisphenol A, and hydrogenated bisphenol A.

[0094] Other usable release agents include petroleum waxes such as paraffin wax, microcrystalline wax, and petrolatum and derivatives thereof, montan wax and derivatives thereof, hydrocarbon waxes produced by the Fischer-Tropsch process and derivatives thereof, polyolefin waxes such as polyethylene and polypropylene and derivatives thereof, natural waxes such as carnauba wax and candelilla wax and derivatives thereof, higher aliphatic alcohols, fatty acids such as stearic acid and palmitic acid, and compounds thereof.

[0095] The content of the release agent is preferably 5.0 parts by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin or polymerizable monomer.

[0096] <Coloring agent> When a colorant is contained in the toner particles, there are no particular limitations, and the following known colorants can be used.

[0097] Yellow pigments that can be used include condensed azo compounds such as yellow iron oxide, Nabels Yellow, Naphthol Yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, and Tartrazine Lake, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specific examples include the following: CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, 180.

[0098] Examples of red pigments include condensed azo compounds such as red iron oxide, permanent red 4R, lithol red, pyrazolone red, watching red calcium salt, lake red C, lake red D, brilliant carmine 6B, brilliant carmine 3B, eosin lake, rhodamine lake B, and alizarin lake, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specific examples include the following: CI Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 254.

[0099] Examples of blue pigments include alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partial chloride, copper phthalocyanine compounds such as fast sky blue and indanthrene blue BG, and derivatives thereof, anthraquinone compounds, and basic dye lake compounds. Specific examples include the following: CI Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, 66.

[0100] Examples of black pigments include carbon black and aniline black. These colorants can be used alone or in combination, or in the form of a solid solution.

[0101] The content of the colorant is preferably 3.0 parts by mass or more and 15.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin or polymerizable monomer.

[0102] <Charge control agents and charge control resins> The toner particles may contain a charge control agent. Any known charge control agent can be used. In particular, a charge control agent that can charge quickly and stably maintain a constant charge amount is preferred.

[0103] As the charge control agent, the following can be mentioned as the agent that controls the toner particles to be negatively charged. Organometallic compounds and chelating compounds include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acid and dicarboxylic acid-based metal compounds. Other examples include aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, or esters, and phenol derivatives such as bisphenols. Further examples include urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, and calixarenes.

[0104] On the other hand, examples of charge control agents that control toner particles to a positive charge include: modified nigrosine compounds; guanidine compounds; imidazole compounds; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate, and onium salts such as phosphonium salts that are analogs of these, and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (lacquering agents include phosphotungstic acid, phosphomolybdic acid, phosphotungstomolybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; and resin-based charge control agents.

[0105] The charge control agents may be contained alone or in combination of two or more kinds. The content of the charge control agent is preferably 0.01 parts by mass or more and 10.00 parts by mass or less with respect to 100.00 parts by mass of the binder resin or polymerizable monomer.

[0106] <External additives> The toner according to the present invention contains hydrotalcite particles as an additive, and it is necessary that the hydrotalcite particles contain fluorine in a filter fitting analysis in a STEM-EDS analysis.

[0107] Hydrotalcite particles are generally represented by the following structural formula (1). M 2+ y M 3+ x (OH)2A n- (x / n) ·mH2O formula (1) where 0 <x≦0.5、y=1-x、m≧0である。 Said M 2+ , and M 3+ denotes divalent and trivalent metals, respectively.

[0108] M 2+is preferably at least one divalent metal ion selected from the group consisting of Mg, Zn, Ca, Ba, Ni, Sr, Cu, and Fe. 3+ is preferably at least one trivalent metal ion selected from the group consisting of Al, B, Ga, Fe, Co, and In.

[0109] A n- is an n-valent anion, CO3 2- , O.H. - , Cl - , I - , F - , Br - , SO4 2- , HCO3 - , CH3COO - , and NO3 - These may be present alone or in combination.

[0110] The hydrotalcite particles according to the present invention are characterized by containing fluorine. There are no particular limitations on the method for incorporating fluorine into the hydrotalcite particles, and examples include a method of treating the hydrotalcite particles with a fluorine-containing coupling treatment agent and a method of treating the hydrotalcite particles in an aqueous solution containing fluoride ions. From the viewpoint of uniform treatment, a wet treatment method in an aqueous solution containing fluoride ions is preferred. In the present invention, the divalent metal ions M 2+ It is preferable that magnesium is contained as the trivalent metal ion M 3+ In other words, the particulate hydrotalcite of the present invention preferably contains fluorine, magnesium, and aluminum. The hydrotalcite particles may be a solid solution containing a plurality of different elements, and may also contain a trace amount of a monovalent metal.

[0111] The number average particle size of the primary particles of the hydrotalcite particles is preferably 60 nm or more and 1000 nm or less, and more preferably 60 nm or more and 800 nm or less. If the number average particle diameter of the primary particles of the hydrotalcite particles is greater than 1000 nm, the fluidity of the toner tends to decrease, and as a result, the charging property during durability testing tends to decrease.

[0112] The hydrotalcite particles may be subjected to a hydrophobic treatment using a surface treatment agent, separate from the fluorine treatment. Examples of the surface treatment agent that can be used include higher fatty acids, coupling agents, esters, and oils such as silicone oil. Among these, higher fatty acids are preferably used, and specific examples include stearic acid, oleic acid, and lauric acid.

[0113] The hydrotalcite particles preferably contain magnesium and aluminum in a filter fitting analysis in a STEM-EDS analysis.

[0114] Furthermore, it is preferable that the hydrotalcite particles have fluorine present inside them in line analysis by STEM-EDS analysis. The presence of fluorine inside the hydrotalcite particles allows the fluorine to migrate to the photoreceptor surface by ion exchange when the hydrotalcite particles migrate to the photoreceptor surface and capture discharge products between their layers. This suppresses moisture absorption on the photoreceptor surface and reduces the formation of liquid bridges between the discharge products on the photoreceptor surface and the toner, thereby further reducing the adhesive force between the photoreceptor surface and the toner, and further improving transferability.

[0115] When the elastic deformation rate of the surface layer of the photoreceptor is η [%] and the content ratio of the hydrotalcite particles in the toner is q [mass %], it is preferable that η and q satisfy the relationship shown in the following formula (A). 100≦η / q≦300 Formula (A) When η and q satisfy the relationship shown in the above formula (A), the positive charge of the hydrotalcite particles can be weakened more efficiently when the toner is rubbed at the contact point between the photosensitive member and the developing member.

[0116] <Method for identifying hydrotalcite particles> The hydrotalcite particles, which are external additives, can be identified by a combination of shape observation using a scanning electron microscope (SEM) and elemental analysis using energy dispersive X-ray analysis (EDS). Using a scanning electron microscope "S-4800" (product name; manufactured by Hitachi, Ltd.), the toner is observed at a maximum magnification of 50,000 times. The focus is set on the surface of the toner particles, and the external additive to be identified is observed. EDS analysis of the external additive to be identified is performed, and the hydrotalcite particles can be identified from the type of element peak. When element peaks observed include an element peak of at least one metal selected from the group consisting of Mg, Zn, Ca, Ba, Ni, Sr, Cu, and Fe, which are metals that can constitute hydrotalcite particles, and an element peak of at least one metal selected from the group consisting of Al, B, Ga, Fe, Co, and In, the presence of hydrotalcite particles containing the two types of metals can be inferred. A sample of the hydrotalcite particles identified by EDS analysis is prepared separately, and its shape is observed by SEM and analyzed by EDS. The results of the analysis of the sample are compared to determine whether they match the results of the analysis of the particles to be identified, and it is determined whether they are hydrotalcite particles.

[0117] [Charged materials] The process cartridge according to the present invention may have a charging member, that is, a charging roller.

[0118] In the configuration of the present invention, the generation of residual toner after transfer can be suppressed by reducing the surface roughness of the charging roller. Specifically, it is preferable that the 10-point average surface roughness Rz of the outer circumferential surface of the charging roller is 5 μm or more and 20 μm or less. By setting the 10-point average surface roughness Rz of the outer peripheral surface of the charging roller to 20 μm or less, the convex portions present on the surface of the charging roller can be made small, and it is further preferable that the 10-point average surface roughness Rz of the outer peripheral surface of the charging roller be 15 μm or less.

[0119] Here, the protrusions on the surface of the charging roller refer to protrusions that are 3 μm or more larger than the average surface height obtained in a surface shape profile of the charging roller obtained by means of a laser microscope, a contact roughness measuring instrument, or the like.

[0120] The charging process involves applying an electric field exceeding Paschen's law in the minute gap between the charging roller and the photoconductor, generating aerial discharge to charge the photoconductor. The protrusions on the surface of the charging roller are closer to the photoconductor than the surrounding area, and the convex shape makes it easier for the electric field to concentrate, resulting in a larger discharge current than the surrounding area. As a result, the surface potential of the photoconductor surface formed by the discharge on the protrusions is higher than the surface potential formed by the discharge around the protrusions.

[0121] In areas of the photoconductor where the surface potential is high, reverse polarity toner (toner with a polarity opposite to that required for development) is likely to be developed onto the photoconductor during the development process. The reverse polarity toner is subject to electrostatic attraction in a direction that causes it to remain on the photoconductor during the transfer process, resulting in residual toner. Therefore, by reducing the height of the protrusions present on the surface of the charging roller and reducing the surface roughness Rz, it is possible to suppress the generation of residual toner on the photosensitive member.

[0122] The ten-point average surface roughness Rz of the charging roller can be measured using a device that can properly measure the control range of the surface roughness of the present invention, such as a laser microscope or a contact-type surface roughness measuring device.

[0123] The ten-point average surface roughness Rz of the charging roller can be controlled by adjusting the conditions during molding of the conductive layer (extrusion, polishing, surface layer formation), or by adding a roughness-forming material such as resin particles or inorganic particles to the conductive layer and controlling the particle size and amount of the particles added. Among these, the method of forming the conductive layer by incorporating resin particles, which are a roughness-forming material, is preferred because it can reduce the area of ​​protrusions on the surface of the charging roller.

[0124] The charging roller as the charging member according to the present invention will be described in detail below. The charging roller preferably has a conductive support and a conductive layer on the outer peripheral surface of the conductive support. The conductive layer may be mainly made of a resin material or a rubber material, but is preferably a conductive elastic layer containing a rubber material in order to ensure favorable contact with the photosensitive member. The conductive elastic layer may have one or more conductive layers on the outer peripheral surface of the conductive support, as long as the effects of the present invention can be achieved.

[0125] <Conductive support> Materials for the conductive support can be appropriately selected from those known in the field of electrophotographic conductive materials and materials usable as such conductive materials. Examples include metals or alloys such as aluminum, stainless steel, conductive synthetic resins, iron, and copper alloys. Furthermore, these may be subjected to oxidation treatment or plating with chromium, nickel, or the like. Both electroplating and electroless plating can be used. From the viewpoint of dimensional stability, electroless plating is preferred. Examples of electroless plating used here include nickel plating, copper plating, gold plating, and various other alloy platings. The plating thickness is preferably 0.05 μm or more, and considering the balance between work efficiency and anti-corrosion performance, the plating thickness is preferably 0.1 μm to 30 μm. When the support is cylindrical, it may be solid or hollow. The outer diameter of the support is preferably in the range of φ3 mm to φ10 mm.

[0126] The material constituting the conductive elastic layer is preferably mainly composed of a rubber material to ensure favorable contact with the photoreceptor. Furthermore, a conductive agent for imparting conductivity and other fillers may be added to the layer within a range that does not impair the effects of the present invention. These materials can be appropriately selected from those known in the field of electrophotographic conductive members, such as those listed below, or from materials that can be used as such conductive members.

[0127] <Rubber materials> Specific examples of rubber materials that can be used to form the conductive elastic layer include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), butyl rubber (IIR), ethylene-propylene-diene terpolymer rubber (EPDM), epichlorohydrin homopolymer (CHC), epichlorohydrin-ethylene oxide copolymer (CHR), epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer (CHR-AGE), acrylonitrile-butadiene copolymer (NBR), hydrogenated acrylonitrile-butadiene copolymer (H-NBR), chloroprene rubber (CR), acrylic rubber (ACM, ANM), and other raw rubbers, as well as liquid rubbers such as liquid butadiene rubber and liquid styrene-butadiene rubber. These can be used alone or in combination of two or more.

[0128] <Conductive materials> As the conductive material that imparts conductivity to the conductive elastic layer, conductive materials such as ionic conductive agents and electronic conductive agents can be appropriately blended. Examples of ionic conductive agents include inorganic ionic substances such as lithium perchlorate, sodium perchlorate, and calcium perchlorate; cationic surfactants such as lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, octadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, trioctylpropylammonium bromide, and modified aliphatic dimethylethylammonium ethosulfate; zwitterionic surfactants such as lauryl betaine, stearyl betaine, and dimethylalkyllauryl betaine; quaternary ammonium salts such as tetraethylammonium perchlorate, tetrabutylammonium perchlorate, and trimethyloctadecylammonium perchlorate; and organic acid lithium salts such as lithium trifluoromethanesulfonate. These can be used alone or in combination of two or more.

[0129] Examples of electronic conductive agents include: fine particles and fibers of metals such as aluminum, palladium, iron, copper, and silver; and metal oxides such as titanium oxide, tin oxide, and zinc oxide that have been treated to be conductive. Composite particles obtained by surface-treating the above-mentioned fine particles, fibers, and metal oxides through electrolytic treatment, spray coating, or mixing and shaking. Carbon powders such as furnace black, thermal black, acetylene black, ketjen black, PAN (polyacrylonitrile)-based carbon, and pitch-based carbon. Examples of furnace black include: SAF-HS, SAF, ISAF-HS, ISAF, ISAF-LS, I-ISAF-HS, HAF-HS, HAF, HAF-LS, T-HS, T-NS, MAF, FEF, GPF, SRF-HS-HM, SRF-LM, ECF, and FEF-HS. Examples of thermal black include FT and MT. Among these, carbon black is preferred because it is relatively easy to obtain and provides good conductivity.

[0130] <Other additives> If necessary, the conductive elastic layer may contain fillers, processing aids, antioxidants, crosslinking aids, crosslinking accelerators, crosslinking accelerator aids, crosslinking retarders, dispersants, foaming agents, resin particles, inorganic particles, and the like, which are generally used as compounding agents for rubber.

[0131] <Resin particles> The conductive elastic layer may contain resin particles or inorganic particles. Resin particles are preferred for favorable contact and rotation with the photoreceptor, and resin particles may be any resin known in the field of electrophotographic conductive members, such as polyurethane resin, polyester resin, polyethylene resin, polyether resin, polyamide resin, acrylic resin, or phenol resin.

[0132] <Method for manufacturing conductive elastic layer> The conductive elastic layer can be produced by mixing the rubber material, conductive material, and other additives using a closed mixer such as a Banbury mixer or a pressure kneader, or an open mixer such as an open roll, and then forming an unvulcanized conductive elastic layer on the outer peripheral surface of the conductive support by a method such as extrusion molding, injection molding, molding, etc. The layer is then vulcanized and hardened by heating or other means, and then subjected to a polishing step and a surface treatment step.

[0133] <Method for controlling the 10-point average surface roughness Rz of a conductive elastic layer> When a charging roller is configured with a conductive support and a conductive elastic layer formed on the outer peripheral surface of the conductive support, the following methods can be used to control the 10-point average surface roughness Rz of the charging roller. One example of a method for controlling the surface roughness is to add resin particles to a rubber material and then remove the rubber material in a polishing process to expose some of the resin particles on the surface of the charging roller. Another example is a method that utilizes the surface shape formed when the rubber material is extruded, or a method that controls the surface shape by further processing.

[0134] Among these, the method of adding resin particles to a rubber material and exposing the resin particles to the surface of the charging roller by a polishing process is preferred, as this method allows for strong discharge on the surface of the charging roller and allows for the independent existence of protrusions that cause residual toner.

[0135] There are no particular restrictions on the particle size of the resin particles added to the conductive elastic layer as long as they can be suitably mixed with the rubber material. However, it is preferable that the average particle size be 10 μm or more and 25 μm or less, because this allows some of the resin particles to be ground and exposed in the polishing process, and makes it easier to control the 10-point average surface roughness Rz of the charging roller within a range that can suppress residual toner after transfer (5 μm or more and 20 μm or less).

[0136] There are no particular restrictions on the amount of resin particles added to the conductive elastic layer as long as they can be suitably mixed with the rubber material. However, since this makes it easier to control the 10-point average surface roughness Rz of the charging roller within a range that can suppress residual toner after transfer (5 μm or more and 20 μm or less), it is preferable that the amount be 5 parts by mass or more and 30 parts by mass or less per 100 parts by mass of the rubber material.

[0137] <Conductive surface layer> Furthermore, as described below, a conductive surface layer may be further formed on the outer peripheral surface of the conductive elastic layer produced as described above. When the charging roller has a two-layer structure, the material constituting the conductive surface layer formed on the outer circumferential surface of the conductive elastic layer formed on the outer circumferential surface of the conductive support contains a binder resin and a conductive material that imparts conductivity, and other additives can be used in combination within a range that does not impair the effects of the present invention. Furthermore, these constituent materials can be appropriately selected from those known in the field of conductive members for electrophotography and materials that can be used as such conductive members.

[0138] <Binder resin> The binder resin material constituting the conductive surface layer can be any resin known in the field of electrophotographic conductive materials. Examples include resins, natural rubber and vulcanized natural rubber, synthetic rubber, and other rubbers. Examples of resins that can be used include epoxy resins, urethane resins, urea resins, ester resins, amide resins, imide resins, amide-imide resins, phenolic resins, vinyl resins, silicone resins, fluororesins, acrylic resins, and butyral resins. Copolymers made from two or more of the monomers that are the raw materials for these resins can also be used.

[0139] <Conductive materials> The conductive material that imparts conductivity to the conductive surface layer can be the same as the conductive material that can be used in the conductive elastic layer described above.

[0140] <Resin particles> An example of a means for controlling the 10-point average surface roughness of the charging roller surface by using a conductive surface layer is to add resin particles or inorganic particles that can act as roughening particles to the conductive surface layer. Resin particles are preferred in order to ensure favorable contact and rotation with the photoreceptor.

[0141] Examples of roughening particles include the following. Materials for the roughening particles include organic insulating particles such as resins known in the field of electrophotographic conductive materials, acrylic resins, polycarbonate resins, styrene resins, urethane resins, fluororesins, and silicone resins; and inorganic insulating particles such as titanium oxide, silica, alumina, magnesium oxide, strontium titanate, barium titanate, barium sulfate, calcium carbonate, mica, zeolite, and bentonite. In the present invention, it is preferable to use flexible organic insulating particles as roughening particles, which can reduce the distance between the convex portions in the discharge section and the photoreceptor. These particles may be used alone or in combination of two or more.

[0142] <Method for controlling the 10-point average surface roughness of the conductive surface layer of a charging roller> The ten-point average surface roughness Rz of the charging roller can be controlled by the roughening particles in the conductive surface layer by adjusting the particle size and the number of added roughening particles. Here, the particle size of the roughening particles refers to the number-average particle size of the roughening particles, and is preferably approximately 3 μm or more and 30 μm or less, since this makes it easy to control the 10-point average surface roughness Rz of the charging roller within a range that can suppress residual toner after transfer (5 μm or more and 20 μm or less). There are no particular restrictions on the amount of roughening particles added to the conductive surface layer as long as they can be suitably mixed with the binder resin. However, since this makes it easier to control the 10-point average surface roughness Rz of the charging roller within a range that can suppress residual toner after transfer (5 μm or more and 20 μm or less), it is preferable that the amount be 5 parts by mass or more and 30 parts by mass or less per 100 parts by mass of the binder resin.

[0143] <Other additives> Other additives may be added to the conductive surface layer of the charging roller as needed, as long as the effects of the present invention are not impaired. It is preferable to add a silicone additive to increase the resistance of the surface layer and provide slipperiness. Furthermore, the surface may be subjected to surface treatment such as the introduction of modified functional groups or molecular chains, coating, or the use of a release agent.

[0144] <Thickness of the conductive surface layer of the charging roller> The thickness of the conductive surface layer is preferably 0.1 μm or more and 100 μm or less, and more preferably 1 μm or more and 50 μm or less. The thickness of the surface layer can be measured by cutting out the cross section of the roller with a sharp blade and observing it with an optical microscope or an electron microscope.

[0145] <Method for manufacturing the conductive surface layer of the charging roller> The method for forming the conductive surface layer is not particularly limited, but examples include spraying, dipping, or roll coating using a paint in which a solvent is added to the raw material. The dip coating method is a simple method for forming a conductive surface layer and has excellent production stability. Furthermore, additional treatment such as heating may be performed after coating, if necessary.

[0146] [Process cartridges, electrophotographic devices] The process cartridge of the present invention is characterized in that it 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 mountable to the main body of the electrophotographic apparatus. The electrophotographic apparatus of the present invention is characterized by comprising the electrophotographic photosensitive member, charging means, exposure means, developing means and transfer means described above.

[0147] 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 101 denotes a cylindrical electrophotographic photoreceptor, which is driven to rotate around shaft 102 in the direction of the arrow at a predetermined peripheral speed. The surface of electrophotographic photoreceptor 101 is charged to a predetermined positive or negative potential by charging means 103. While the figure shows a roller charging method using a roller-type charging member, other charging methods, such as corona charging, proximity charging, and injection charging, may also be used. Exposure light 104 from an exposure means (not shown) is irradiated onto the charged surface of electrophotographic photoreceptor 101, forming an electrostatic latent image corresponding to the desired image information. The electrostatic latent image formed on the surface of electrophotographic photoreceptor 101 is developed with toner contained in developing means 105, forming a toner image on the surface of electrophotographic photoreceptor 101. The toner image formed on the surface of electrophotographic photoreceptor 101 is transferred to transfer material 107 by transfer means 106. The transfer material 107 to which the toner image has been transferred is transported to fixing means 108, where the toner image is fixed and printed out from the electrophotographic apparatus. The electrophotographic apparatus may have cleaning means 109 for removing deposits such as toner remaining on the surface of the electrophotographic photosensitive member 101 after transfer. Alternatively, a so-called cleanerless system may be used in which the deposits are removed by a developing means or the like without providing a separate cleaning means. The electrophotographic apparatus may have a charge-removing mechanism that performs a charge-removing process on the surface of the electrophotographic photosensitive member 101 with pre-exposure light 110 from a pre-exposure means (not shown). Also, guide means 112 such as a rail may be provided for attaching and detaching the process cartridge 111 of the present invention to and from the main body of the electrophotographic apparatus.

[0148] The electrophotographic photoreceptor of the present invention can be used in laser beam printers, LED printers, copiers, and the like. [Example]

[0149] The present invention will be described in more detail below using examples and comparative examples. The present invention is not limited to the following examples without departing from the gist of the present invention. In the following description of the examples, "parts" are by mass unless otherwise specified.

[0150] <Production of electrophotographic photoreceptors> Manufacturing method of [Photoreceptor 1] ■Support An aluminum tube with a mirror-finished surface, 1 mm thick, 257 mm long, and 24 mm diameter, was degreased and washed for 5 minutes at 60°C in a solution of 30 g of degreasing agent (manufactured by Kizai Corporation, product name NG-#30) dissolved in 1 L of water. It was then rinsed with water, immersed in 6% nitric acid for 1 minute at 25°C, and then rinsed again with water. Anodizing was performed in a 180 g / L sulfuric acid electrolyte (dissolved aluminum ion concentration 7 g / L) at 0.8 A / dm 2 The substrate was treated at a current density of 1000 kJ / cm2, forming an anodized film with an average thickness of 4.5 μm. After rinsing with water, the substrate was immersed in an aqueous solution of 10 g of a high-temperature sealing agent (manufactured by Okuno Chemical Industries Co., Ltd., product name: Topseal DX-500) containing nickel acetate as the main component dissolved in 1 L of water at 95°C for 30 minutes to perform a sealing treatment. The substrate was then ultrasonically cleaned and dried, and used as a conductive support.

[0151] ■ Charge generation layer Next, 10 parts of polyvinyl butyral resin (product name: S-LEC BX-1, manufactured by Sekisui Chemical Co., Ltd.) was dissolved in 600 parts of cyclohexanone. To this solution, 15 parts of oxytitanium phthalocyanine crystals, a crystalline form exhibiting a strong peak at 27.3°, Bragg angle 2θ±0.2°, in CuKα characteristic X-ray diffraction, was added as a charge-generating substance. The mixture was placed in a sand mill using 1 mm diameter glass beads and dispersed for 4 hours. Then, 600 parts of ethyl acetate was added to prepare a charge-generating layer coating solution. This charge-generating layer coating solution was dip-coated onto the support, and the resulting coating was dried at 80°C for 15 minutes to form a charge-generating layer with a thickness of 0.20 μm.

[0152] ■Charge transport layer Next, 75 parts of a compound (charge transport material) represented by the following formula (CTM-1) and 75 parts of a biphenyl copolymer polycarbonate resin (weight average molecular weight 30,000) having a structural unit represented by (Binder-1) and a structural unit represented by (Binder-2) in a mass ratio of 9:1 were dissolved in a mixed solvent of 340 parts toluene and 200 parts tetrahydrofuran to prepare a coating solution for the charge transport layer. [ka] [ka] [ka] 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 120° C. for 60 minutes to form a charge transport layer having a thickness of 25.5 μm.

[0153] ■Protective layer Next, the following materials were prepared: 25 parts of the compound represented by the above formula (D-6) as OCL monomer 1 75 parts of the compound represented by the above formula (B-1) as OCL monomer 2 These were mixed with a mixed solvent of 360 parts of 2-propanol and 40 parts of tetrahydrofuran and stirred to prepare a coating liquid for a protective layer. This protective layer coating solution was dip-coated onto the charge transport layer to form a coating film, which was then dried at 50°C for 6 minutes. The coating film was then irradiated with an electron beam for 2.0 seconds under a nitrogen atmosphere while rotating the support (irradiated object) at a speed of 300 rpm under conditions of an acceleration voltage of 70 kV and a beam current of 5.0 mA. The dose at the protective layer position was 14 kGy. The coating film was then heated to 120°C under a nitrogen atmosphere. The oxygen concentration from electron beam irradiation to the subsequent heat treatment was 15 ppm. The coating film was then naturally cooled in the atmosphere to 25°C, and then heat-treated for 1 hour under conditions that brought the coating film temperature to 120°C, forming a protective layer with a thickness of 3.5 μm. In this manner, photoreceptor 1 was prepared.

[0154] Manufacturing methods for [Photoreceptor 2] to [Photoreceptor 31] and [Comparative Photoreceptor 1] to [Comparative Photoreceptor 12] In the manufacturing method of [Photoreceptor 1], the material and number of copies of the protective layer and the electron beam irradiation conditions for the protective layer were changed as shown in Table 1 below. Otherwise, [Photoreceptor 2] to [Photoreceptor 31] and [Comparative Photoreceptor 1] to [Comparative Photoreceptor 12] were manufactured in the same manner as the manufacturing method of [Photoreceptor 1].

[0155] Formulas (E-1) to (E-4), formulas (F-1) to (F-3), and formulas (G-1) to (G-2) in Table 1 are shown below. [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0156] [Table 1]

[0157] Manufacturing method of [photoreceptor 32] A charge generating layer and a charge transporting layer were formed on a support in the same manner as in Example 1. Next, the following materials were prepared. 50 parts of the compound represented by the above formula (D-6) as OCL monomer 1 50 parts of the compound represented by the above formula (B-1) as OCL monomer 2 5 parts of 1-hydroxycyclohexyl phenyl ketone as a polymerization initiator These were mixed with a mixed solvent of 360 parts of 2-propanol and 40 parts of tetrahydrofuran and stirred to prepare a coating liquid for a protective layer. This protective layer coating solution was dip-coated onto the charge transport layer to form a coating film, and the resulting coating film was dried for 6 minutes at 50° C. Thereafter, in a nitrogen atmosphere, an electrodeless lamp H bulb (manufactured by Heraeus K.K.) was used, and the lamp intensity was 0.7 W / cm. 2 Under these conditions, the support (irradiated object) was rotated at a speed of 300 rpm, and the coating film was irradiated with ultraviolet light for 20 seconds. The temperature of the coating film was then raised to 120°C in a nitrogen atmosphere. The oxygen concentration from the time of ultraviolet irradiation to the time of the subsequent heat treatment was 15 ppm. Next, the coating film was naturally cooled in the atmosphere until the temperature reached 25°C, and then heat-treated for 1 hour under conditions that brought the temperature of the coating film to 120°C, forming a protective layer with a thickness of 3.5 μm. In this manner, photoreceptor 32 was produced.

[0158] Manufacturing methods for [Photoreceptor 33] to [Photoreceptor 36] and [Comparative Photoreceptor 13] to [Comparative Photoreceptor 16] In the manufacturing method of [Photoreceptor 32], the material and number of copies of the protective layer and the ultraviolet irradiation conditions for the protective layer were changed as shown in Table 2 below. Otherwise, [Photoreceptor 33] to [Photoreceptor 36] and [Comparative Photoreceptor 13] to [Comparative Photoreceptor 16] were manufactured in the same manner as the manufacturing method of [Photoreceptor 32].

[0159] [Table 2]

[0160] ■ Photoconductor analysis <Method for measuring elastic deformation rate> The elastic deformation rate of the surface layer of the photoreceptor was measured using a Fischer hardness tester (product name: H100VP-HCU, manufactured by Fischer) under a high temperature and high humidity (30°C / 80%RH) environment (HH environment). A Vickers square pyramid diamond indenter with a facing angle of 136° was used as the indenter. The indenter was pressed into the surface of the surface layer to be measured, and a load was applied up to 2mN over 7 seconds, and then gradually reduced over 7 seconds, and the indentation depth was continuously measured until the load reached 0mN. The elastic deformation rate was calculated from the results.

[0161] <Analysis of (meth)acrylic resins with urethane structures> The presence or absence of a urethane structure and a (meth)acrylic resin in the surface layer of the photoreceptor was analyzed using pyrolysis GCMS and FTIR as follows.

[0162] <Pyrolysis GCMS> The surface layer of the prepared photoreceptor was peeled off by scraping it off with a razor. The peeled surface layer was immersed in chloroform and irradiated with ultrasound for 1 hour using an ultrasonic device. The components insoluble in chloroform were then removed and dried to obtain a residue. The residue was then mixed with a TMAH methylating agent, and the mixture was analyzed under the following measurement conditions. From the analysis results, it was confirmed whether compounds derived from urethane structures and (meth)acrylic resins were detected, and the structure before thermal decomposition was estimated. (Measurement conditions) Pyrolysis device: JPS-700 (Japan Analysis Industry) Decomposition temperature: 590℃ GC / MS equipment: Focus GC / ISQ (Thermo Fisher) Column: HP-5MS, length 60 m, inner diameter 0.25 mm, film thickness 0.25 μm Inlet temperature: 200℃ Flow pressure: 100kPa Split: 50mL / min MS ionization: EI Ion source temperature: 200℃ Mass Range 45-650

[0163] <ftir> The surface layer of the photoreceptor was measured at 600cm by Fourier transform infrared total reflection spectroscopy. -1 ~4000cm -1 The infrared spectrum was measured under the following conditions, and it was confirmed that it was consistent with the structure estimated from the pyrolysis GCMS results. (Measurement conditions) Instrument: FT / IR-420 (JASCO Corporation) Accessory equipment: ATR equipment IRE (Internal Reflection Element): Ge Incident angle: 45 degrees Accumulation count: 32

[0164] <Toner manufacturing> <Preparation example of resin particle dispersion 1> 70.0 parts styrene 28.7 parts butyl acrylate 1.3 parts acrylic acid 3.2 parts n-lauryl mercaptan The above materials were placed in a container and mixed by stirring. An aqueous solution of 1.5 parts of Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 150.0 parts of ion-exchanged water was added to this solution and dispersed. An aqueous solution of 0.3 parts potassium persulfate and 10.0 parts ion-exchanged water was added with slow stirring for an additional 10 minutes. After nitrogen substitution, emulsion polymerization was carried out at 70°C for 6 hours. After polymerization was completed, the reaction solution was cooled to room temperature, and ion-exchanged water was added to obtain resin particle dispersion 1 with a solids concentration of 12.5% ​​by mass and a glass transition temperature of 48°C. The particle size distribution of the resin particles contained in this resin particle dispersion 1 was measured using a particle size analyzer (HORIBA, Ltd., LA-920), and the number-average particle size of the resin particles contained was 0.2 μm. Furthermore, no coarse particles exceeding 1 μm were observed.

[0165] <Preparation example of resin particle dispersion 2> 78.0 parts styrene 20.7 parts butyl acrylate 1.3 parts acrylic acid 3.2 parts n-lauryl mercaptan The above materials were placed in a container and mixed by stirring. An aqueous solution of 1.5 parts of Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 150.0 parts of ion-exchanged water was added to this solution and dispersed. While slowly stirring for another 10 minutes, an aqueous solution of 0.3 parts potassium persulfate and 10.0 parts ion-exchanged water was added. After nitrogen substitution, emulsion polymerization was carried out at 70°C for 6 hours. After polymerization was completed, the reaction solution was cooled to room temperature, and ion-exchanged water was added to obtain resin particle dispersion 2 with a solids concentration of 12.5% ​​by mass and a glass transition temperature of 60°C. The particle size distribution of the resin particles contained in this resin particle dispersion 2 was measured using a particle size analyzer (HORIBA, Ltd., LA-920), and the number-average particle size of the resin particles contained was 0.2 μm. Furthermore, no coarse particles exceeding 1 μm were observed.

[0166] <Preparation example of resin particle dispersion 3> 76.0 parts styrene 22.7 parts butyl acrylate 1.3 parts acrylic acid 3.2 parts n-lauryl mercaptan The above materials were placed in a container and mixed by stirring. An aqueous solution of 1.5 parts of Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 150.0 parts of ion-exchanged water was added to this solution and dispersed. While slowly stirring for another 10 minutes, an aqueous solution of 0.3 parts potassium persulfate and 10.0 parts ion-exchanged water was added. After nitrogen substitution, emulsion polymerization was carried out at 70°C for 6 hours. After polymerization was completed, the reaction solution was cooled to room temperature, and ion-exchanged water was added to obtain resin particle dispersion 3 with a solids concentration of 12.5% ​​by mass and a glass transition temperature of 58°C. The particle size distribution of the resin particles contained in this resin particle dispersion 3 was measured using a particle size analyzer (HORIBA, Ltd., LA-920), and the number-average particle size of the resin particles contained was 0.2 μm. Furthermore, no coarse particles exceeding 1 μm were observed.

[0167] <Preparation example of release agent dispersion 1> 100.0 parts of behenyl behenate (melting point: 72.1°C) and 15.0 parts of Neogen RK were mixed with 385.0 parts of ion-exchanged water and dispersed for about 1 hour using a wet jet mill JN100 (manufactured by Joko Corporation) to obtain release agent dispersion 1. The wax concentration of release agent dispersion 1 was 20.0 mass%. The particle size distribution of the release agent particles contained in this release agent dispersion 1 was measured using a particle size measuring device (manufactured by Horiba, Ltd., LA-920), and the number average particle size of the release agent particles contained was 0.35 µm. Furthermore, no coarse particles exceeding 1 µm were observed.

[0168] <Preparation example of release agent dispersion 2> 100.0 parts of hydrocarbon wax HNP-9 (manufactured by Nippon Seiro Co., Ltd., melting point: 75.5°C) and 15 parts of Neogen RK were mixed with 385.0 parts of ion-exchanged water, and the mixture was dispersed for about 1 hour using a wet jet mill JN100 (manufactured by Jokou Corporation) to obtain release agent dispersion 2. The wax concentration of release agent dispersion 2 was 20.0% by mass. The particle size distribution of the release agent particles contained in this release agent dispersion 2 was measured using a particle size measuring device (manufactured by Horiba, Ltd., LA-920), and the number average particle size of the release agent particles contained was 0.35 μm. Furthermore, no coarse particles exceeding 1 μm were observed.

[0169] <Preparation example of colorant dispersion 1> 50.0 parts of copper phthalocyanine (Pigment Blue 15:3) as a colorant and 5.0 parts of Neogen RK were mixed with 200.0 parts of ion-exchanged water and dispersed for approximately 1 hour using a wet jet mill JN100 to obtain Colorant Dispersion 1. The solids concentration of Colorant Dispersion 1 was 20.0% by mass. The particle size distribution of the colorant particles contained in Colorant Dispersion 1 was measured using a particle size analyzer (HORIBA, Ltd., LA-920), and the number-average particle size of the colorant particles contained was 0.20 μm. Furthermore, no coarse particles exceeding 1 μm were observed.

[0170] Manufacturing method of [Toner particles 1] ·Resin particle dispersion 1:265.0 parts Release agent dispersion 1:10.0 parts Release agent dispersion 2: 8.0 parts Colorant dispersion 1:8.0 parts To form the core of the toner particles, the above materials were placed in a round stainless steel flask and mixed. Then, a homogenizer (IKA Ultra Turrax T50) was used to disperse the mixture at 5000 rpm for 10 minutes. While stirring, the temperature inside the container was adjusted to 30°C, and a 1 mol / L aqueous solution of sodium hydroxide was added to adjust the pH to 8.0. As a flocculant, an aqueous solution of 0.25 parts aluminum chloride dissolved in 10.0 parts ion-exchanged water was added to the mixture at 30°C over 10 minutes with stirring. After leaving the mixture for 3 minutes, the temperature was raised to 60°C to form aggregated particles (core formation). The volume-based median diameter of the formed aggregated particles was conveniently measured using a Coulter Counter Multisizer 3 (registered trademark, manufactured by Beckman Coulter). When the volume-based median diameter reached 7.0 μm, 2:15.0 parts of resin particle dispersion was added and the mixture was stirred for another hour to form a shell. Thereafter, a 1 mol / L aqueous solution of sodium hydroxide was added to adjust the pH to 9.0, and the temperature was raised to 95° C. to spheronize the aggregated particles. When the average circularity reached 0.980, the temperature was lowered and the mixture was cooled to room temperature, thereby obtaining toner particle dispersion 1. Hydrochloric acid was added to the obtained toner particle dispersion 1 to adjust the pH to 1.5 or less, and the mixture was stirred and left for 1 hour before undergoing solid-liquid separation using a pressure filter to obtain a toner cake. This was reslurried with ion-exchanged water to make a dispersion again, and then subjected to solid-liquid separation using the aforementioned filter. The reslurrying and solid-liquid separation were repeated until the electrical conductivity of the filtrate reached 5.0 μS / cm or less, after which solid-liquid separation was finally performed to obtain a toner cake. The obtained toner cake was dried and further classified using a classifier so that the volume-based median diameter was 7.0 μm, obtaining toner particles 1.

[0171] Method for producing toner particles 2 to 9 In the manufacturing method of [Toner Particles 1], the type and amount of aggregating agent added were changed as shown in Table 3 below. Otherwise, [Toner Particles 2] to [Toner Particles 9] were manufactured in the same manner as the manufacturing method of [Toner Particles 1].

[0172] [Table 3]

[0173] Method for producing toner particles 10 ·Resin particle dispersion 3: 265.0 parts Release agent dispersion 1:10.0 parts Release agent dispersion 2: 8.0 parts Colorant dispersion 1:8.0 parts To form the core of the toner particles, the above materials were placed in a round stainless steel flask and mixed. Then, a homogenizer (IKA Ultra Turrax T50) was used to disperse the mixture at 5000 rpm for 10 minutes. While stirring, the temperature inside the container was adjusted to 30°C, and a 1 mol / L aqueous solution of sodium hydroxide was added to adjust the pH to 8.0. An aqueous solution of 0.25 parts aluminum chloride dissolved in 10.0 parts ion-exchanged water was added as an aggregating agent at 30°C over 10 minutes with stirring. After leaving the mixture for 3 minutes, the temperature was raised to 60°C to form aggregated particles (core formation). The volume-based median diameter of the formed aggregated particles was conveniently measured using a Coulter Counter Multisizer 3 (registered trademark, manufactured by Beckman Coulter, Inc.). When the volume-based median diameter reached 7.0 μm, a 1 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 9.0, and the mixture was then heated to 95°C to spheronize the aggregated particles. When the average circularity reached 0.980, the temperature was lowered and the mixture was cooled to room temperature to obtain Toner Particle Dispersion 2. Hydrochloric acid was added to the obtained toner particle dispersion 2 to adjust the pH to 1.5 or less, and the mixture was stirred and left for 1 hour. Then, solid-liquid separation was performed using a pressure filter to obtain a toner cake. This was reslurried with ion-exchanged water to form a dispersion again, and then solid-liquid separation was performed using the aforementioned filter. The reslurrying and solid-liquid separation were repeated until the electrical conductivity of the filtrate reached 5.0 μS / cm or less, after which solid-liquid separation was finally performed to obtain a toner cake. The obtained toner cake was dried and further classified using a classifier to obtain a volume-based median diameter of 7.0 μm, thereby obtaining toner particles 10.

[0174] Method for producing [hydrotalcite particles 1] A mixed aqueous solution of 1.03 mol / L magnesium chloride and 0.239 mol / L aluminum sulfate (liquid A), a 0.753 mol / L sodium carbonate aqueous solution (liquid B), and a 3.39 mol / L sodium hydroxide aqueous solution (liquid C) were prepared. Next, solutions A, B, and C were added to a reaction vessel using a metering pump at a flow rate such that the volume ratio of solution A to solution B was 4.5:1. The pH of the reaction solution was maintained in the range of 9.3 to 9.6 using solution C, and the reaction temperature was 40°C to form a precipitate. After filtration and washing, the mixture was re-emulsified in ion-exchanged water to obtain a raw hydrotalcite slurry. The hydrotalcite concentration in the resulting hydrotalcite slurry was 5.6% by mass. The resulting hydrotalcite slurry was vacuum-dried overnight at 40°C. NaF was dissolved in ion-exchanged water to a concentration of 100 mg / L, and the pH was adjusted to 7.0 using 1 mol / L HCl or 1 mol / L NaOH. The dried hydrotalcite was added to the slurry to a concentration of 0.1% (w / v%). The mixture was stirred at a constant speed using a magnetic stirrer for 48 hours to prevent precipitation. The mixture was then filtered through a 0.5 μm pore membrane filter and washed with ion-exchanged water. The obtained hydrotalcite was dried in vacuum at 40°C overnight and then crushed.

[0175] Method for producing [Hydrotalcite particles 2] to [Hydrotalcite particles 13] In the method for producing [hydrotalcite particles 1], the volume ratio of liquid A:liquid B and the concentration of the NaF aqueous solution were adjusted appropriately.Otherwise, [hydrotalcite particles 2] to [hydrotalcite particles 13] were produced in the same manner as in the method for producing [hydrotalcite particles 1].

[0176] Method for producing [hydrotalcite particles 14] [Hydrotalcite particles 14] were produced in the same manner as in the production method of [Hydrotalcite particles 1], except that ion-exchanged water was used instead of the NaF aqueous solution.

[0177] Method for producing [hydrotalcite particles 15] A mixed aqueous solution of 1.03 mol / L magnesium chloride and 0.239 mol / L aluminum sulfate (liquid A), a 0.753 mol / L sodium carbonate aqueous solution (liquid B), and a 3.39 mol / L sodium hydroxide aqueous solution (liquid C) were prepared. Next, liquid A, liquid B, and liquid C were poured into a reaction vessel using a metering pump at a flow rate such that the volume ratio of liquid A to liquid B was 4.5:1. The pH value of the reaction solution was maintained in the range of 9.3 to 9.6 using liquid C, and the reaction temperature was 40°C to generate a precipitate. After filtration and washing, the mixture was re-emulsified in ion-exchanged water to obtain a raw material hydrotalcite slurry. The hydrotalcite in the obtained hydrotalcite slurry had a concentration of 5.6% by mass. The obtained hydrotalcite slurry was maintained at 95°C, and surface treatment was performed by adding 5 parts by mass of fluorosilicone oil to 95 parts by mass of solids. Next, the mixture was filtered and washed with water, dried at 100°C for 24 hours, and crushed using an atomizer mill (manufactured by Dalton Co., Ltd.) to obtain hydrotalcite particles 15.

[0178] Manufacturing method of [Toner 1] 100.0 parts of the toner particles 1 obtained above were externally mixed with 0.3 parts of hydrotalcite particles 1 and 1.5 parts of silica particles 1 (RX200: average primary particle size 12 nm, HMDS treatment, manufactured by Nippon Aerosil Co., Ltd.) using an FM10C (manufactured by Nippon Coke and Engineering Co., Ltd.) The external addition conditions were as follows: the lower blade was set to A0 blade, the gap between the deflector wall was set to 20 mm, the amount of toner particles charged was 2.0 kg, the rotation speed was 66.6 s-1, the external addition time was 10 minutes, and the cooling water temperature was 20°C and the flow rate was 10 L / min. Thereafter, the mixture was sieved through a mesh having an opening of 200 μm to obtain Toner 1.

[0179] Manufacturing methods for [Toner 2] to [Toner 25] and [Comparative Toner 1] In the manufacturing method of [Toner 1], the type of toner particles and the type and amount of hydrotalcite particles added were changed as shown in Table 4 below. Otherwise, [Toner 2] to [Toner 25] and [Comparative Toner 1] were manufactured in the same manner as the manufacturing method of [Toner 1].

[0180] Manufacturing method of [Comparative Toner 2] In the manufacturing method of [Toner 1], hydrotalcite particles 1 were changed to polytetrafluoroethylene fine particles "Fluoro A" (manufactured by Shamrock, average primary particle size 0.3 μm). Otherwise, [Comparative Toner 2] was manufactured in the same manner as [Toner 1].

[0181] Manufacturing method of [Comparative Toner 3] Comparative Toner 2 was produced in the same manner as Toner 1, except that the hydrotalcite particles 1 were replaced with fluorine-containing alumina particles.

[0182] [Table 4]

[0183] The obtained toners 1 to 25 and comparative toners 1 to 3 were analyzed to determine whether the hydrotalcite particles contained fluorine, magnesium, and aluminum, and, if fluorine was contained, whether fluorine was present inside the hydrotalcite particles. The content q of the hydrotalcite particles relative to the toner was also measured. The results are shown in Table 5 below.

[0184] [Table 5]

[0185] ■ Toner analysis <Method for analyzing each element in hydrotalcite particles> Analysis of each element in the hydrotalcite particles is carried out by EDS mapping measurement of the toner using a scanning transmission electron microscope (TEM). EDS mapping measurement has spectral data for each pixel in the analysis area, and by using a silicon drift detector with a large detection element area, EDS mapping can be measured with high sensitivity. By performing statistical analysis on the spectral data for each pixel obtained by EDS mapping measurement, it is possible to obtain a principal component mapping that extracts pixels with similar spectra, making it possible to map specific components.

[0186] The sample for observation is prepared according to the following procedure. 0.5 g of toner is weighed out and placed in a cylindrical mold with a diameter of 8 mm using a Newton press, which is left to stand for 2 minutes under a load of 40 kN to prepare a cylindrical toner pellet with a diameter of 8 mm and a thickness of approximately 1 mm. A 200 nm thick thin section is prepared from the toner pellet using an ultramicrotome (Leica, FC7). STEM-EDS analysis was performed using the following equipment and conditions. Measuring instrument 1: Scanning transmission electron microscope; JEOL JEM-2800 Measurement equipment 2: EDS detector; JEOL JED-2300T dry SD100GV detector (detector area: 100 mm 2 ) Measurement equipment used 3: EDS analyzer; NORAN System 7 manufactured by Thermo Fisher Scientific (STEM-EDS requirements) STEM accelerating voltage: 200kV ·Magnification: 20,000x Probe size: 1nm STEM image size: 1024 x 1024 pixels (EDS elemental mapping images are acquired at the same position.) EDS mapping size: 256 x 256 pixels, Dwell time: 30 μs, Integration count: 100 frames The ratio of polyvalent metal elements in the toner particles and the ratio of each element in the hydrotalcite particles were calculated based on multivariate analysis as follows. The filter fitting analysis according to the present invention will now be described. EDS mapping was obtained using the STEM-EDS analyzer. The collected spectral mapping data was then subjected to multivariate analysis using the COMPASS (PCA) mode in the measurement command of the NORAN System 7, and principal component map images were extracted. In this case, the setting values ​​were as follows: Kernel size: 3×3 Quantitative map setting: High (slow) Filter Fit Type: High Precision (Slow) At the same time, this operation also calculates the area ratio of each extracted principal component to the EDS measurement field of view.Quantitative analysis was performed on the obtained EDS spectra of each principal component using the Cliff-Lorimer method. Distinguishing between toner particles and hydrotalcite particles is done based on the quantitative analysis results of the obtained STEM-EDS principal component mapping. Particles can be identified as hydrotalcite particles based on particle size, shape, content of polyvalent metals such as aluminum and magnesium, and their quantitative ratios. Furthermore, when fluorine is present in hydrotalcite particles, the particles can be determined as fluorine-containing hydrotalcite particles by the following method.

[0187] (Method for analyzing fluorine contained in hydrotalcite particles) Based on the mapping data obtained by the STEM-EDS analysis using the method described above, the fluorine contained in the hydrotalcite particles is analyzed. If the EDS spectrum obtained from the principal component mapping image of the particle extracted by COMPASS has a fluorine peak intensity that is 1.5 times or more the background intensity, it is determined that the particle contains fluorine.

[0188] <Method for analyzing fluorine inside hydrotalcite particles> Based on the mapping data obtained by the STEM-EDS analysis using the method described above, fluorine inside the hydrotalcite particles is analyzed. Specifically, EDS line analysis is performed in the normal direction of the particle surface to analyze the fluorine present inside. A schematic diagram of the line analysis is shown in Figure 2(a). For toner particle 1 and hydrotalcite particle 3 adjacent to toner particle 2, line analysis is performed in the normal direction to the outer periphery of hydrotalcite particle 3, i.e., in the direction of 5. Note that 4 indicates the boundary of the toner particle. The area in the acquired STEM image where the relevant particles existed was selected using the rectangular selection tool, and line analysis was performed under the following conditions. (Line analysis conditions) ·STEM magnification; 800,000x Line length: 200nm Line width: 30nm Number of line divisions: 100 points (measure intensity every 2 nm) or When the fluorine element peak intensity in the EDS spectrum of the hydrotalcite particle is 1.5 times or more the background intensity, and when the fluorine element peak intensity at both ends of the hydrotalcite particle in line analysis (points a and b in Figure 2(a)) does not exceed 3.0 times the peak intensity at point c, the element is determined to be contained inside the hydrotalcite particle. Point c is the midpoint of line segment ab (i.e., the midpoint of the above-mentioned both ends). Examples of fluorine X-ray intensities obtained by line analysis are shown in Figures 2(b) and 2(c). When hydrotalcite particles contain fluorine internally, the graph of X-ray intensity normalized by peak intensity will have a shape like that shown in Figure 2(b). When hydrotalcite particles contain fluorine derived from a surface treatment agent, the graph of X-ray intensity normalized by peak intensity will have peaks near points a and b, both ends of the fluorine graph, as shown in Figure 2(c). By checking the fluorine-derived X-ray intensity in line analysis, it can be confirmed that the hydrotalcite particles contain fluorine internally.

[0189] <Method for measuring the content ratio q of hydrotalcite particles in toner> The content ratio q of hydrotalcite particles in the toner can be quantified using fluorescent X-ray analysis and a calibration curve created from a standard sample. The fluorescent X-ray measurement of each element conforms to JIS K 0119-1969, and is specifically as follows. The measurement equipment used was a wavelength dispersive X-ray fluorescence analyzer "Axios" (PANalytical) and the accompanying dedicated software "SuperQ ver.4.0F" (PANalytical) for setting measurement conditions and analyzing measurement data. Rh was used as the anode of the X-ray tube, the measurement atmosphere was vacuum, the measurement diameter (collimator mask diameter) was 27 mm, and the measurement time was 10 seconds. Light elements were detected using a proportional counter (PC), and heavy elements were detected using a scintillation counter (SC). The measurement sample was prepared by placing approximately 4 g of toner in a special aluminum ring for pressing, flattening it, and then pressing it at 20 MPa for 60 seconds using a tablet press to form pellets with a thickness of approximately 2 mm and a diameter of approximately 39 mm. The tablet press used was the "BRE-32" manufactured by Mayekawa Testing Machinery Co., Ltd. Measurements are carried out under the above conditions, and elements are identified based on the peak positions of the obtained X-rays. Their concentrations are then calculated from the counting rate (unit: cps), which is the number of X-ray photons per unit time. To 100 parts by mass of toner not containing hydrotalcite particles, a separately prepared sample of hydrotalcite particles is added so that the amount is 0.10 parts by mass, and the mixture is thoroughly mixed using a coffee mill. Similarly, 0.20 parts by mass and 0.50 parts by mass of hydrotalcite particles are mixed with the toner, respectively, and these are used as samples for the calibration curve. For each sample, the count rate (unit: cps) derived from the metal elements in the hydrotalcite is measured. At this time, the acceleration voltage and current value of the X-ray generator are set to 24 kV and 100 mA, respectively. A linear calibration curve is obtained by plotting the obtained X-ray count rate on the vertical axis and the amount of hydrotalcite particles added in each calibration curve sample on the horizontal axis. Next, the toner to be analyzed is pelletized as described above using a tablet molding compressor, and the counting rate derived from the metal elements in the hydrotalcite is measured. Then, the content ratio q of the hydrotalcite particles in the toner is determined from the calibration curve.

[0190] <Manufacturing of charging members (charging rollers)> Manufacturing method of [Charging roller 1] <1. Preparation of Rubber Mixture for Molding Conductive Elastic Layer> The materials shown in Table 6 were mixed in the amounts shown in Table 6 in a 6L pressure kneader (product name: TD6-15MDX, manufactured by Toshin Co., Ltd.) to obtain an unvulcanized rubber mixture. The mixing conditions were a filling rate of 70 vol%, a blade rotation speed of 30 rpm, and a time of 16 minutes.

[0191] [Table 6]

[0192] Furthermore, the unvulcanized rubber mixture obtained above was mixed with each material in the types and amounts shown in Table 7 below using an open roll to prepare a rubber mixture for forming a conductive elastic layer. The mixer used was an open roll with a roll diameter of 12 inches. The mixing conditions were a front roll rotation speed of 10 rpm, a rear roll rotation speed of 8 rpm, a roll gap of 2 mm, and a total of 20 left and right turns, followed by 10 thin passes with a roll gap of 1.0 mm.

[0193] [Table 7]

[0194] <2. Forming the conductive elastic layer> A round bar with a total length of 252 mm and an outer diameter of 6 mm was prepared. The surface of the free-cutting steel bar was electrolessly nickel-plated. Next, using a roll coater, an adhesive "Metalock U-20" (trade name, manufactured by Toyo Kagaku Kenkyusho) was applied to the entire circumference of the round bar, excluding 11 mm at each end. In this example, the adhesive-coated round bar was used as a conductive support. Next, a die with an inner diameter of 10.0 mm was attached to the tip of a crosshead extruder having a mechanism for feeding the conductive support and a mechanism for discharging the unvulcanized rubber roller, and the temperatures of the extruder and crosshead were adjusted to 100°C, and the conveying speed of the conductive support was adjusted to 60 mm / sec. Under these conditions, the rubber mixture for forming the conductive elastic layer was fed from the extruder, and the outer periphery of the conductive support was coated with the rubber mixture for forming the conductive elastic layer in the crosshead, thereby obtaining an unvulcanized rubber roller. Next, the unvulcanized rubber roller was placed in a hot-air vulcanizing furnace at 170°C and heated for 60 minutes to vulcanize the layer of unvulcanized rubber composition, resulting in a roller with a conductive resin layer formed on the outer peripheral surface of the conductive support. After that, 12 mm of each end of the conductive resin layer was cut off, leaving a longitudinal length of 228 mm for the conductive resin layer portion. Finally, the surface of the conductive resin layer was polished with a rotary grindstone, thereby obtaining a charging roller A with a conductive layer, which had a diameter of 8.5 mm at positions 90 mm from the center to both ends and a central diameter of 8.6 mm.

[0195] <3. Forming the conductive surface layer> Furthermore, a conductive surface layer was formed on the charging roller A with a conductive layer produced as described above in the following manner. First, methyl isobutyl ketone was added to the caprolactone-modified acrylic polyol solution to adjust the solid content to 10% by mass. A mixed solution was prepared using 1000 parts by mass of this acrylic polyol solution (100 parts by mass of solid content) and the materials shown in Table 8 below. At this time, the mixture of block HDI and block IPDI had an "NCO / OH=1.0".

[0196] [Table 8]

[0197] Next, 210 g of the mixed solution and 200 g of glass beads having an average particle size of 0.8 mm as a medium were mixed in a 450 mL glass bottle, and pre-dispersed for 24 hours using a paint shaker disperser. Furthermore, 30 parts by mass of polyurethane particles with an average particle size of 9.0 μm (product name: Dynamic Beads UCN-5090, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.) were added to the glass bottle containing the dispersed paint, per 100 parts by mass of caprolactone-modified acrylic polyol, and the mixture was dispersed again for 10 minutes using a paint shaker to obtain a paint for forming a surface layer. The conductive layer-equipped charging roller A was immersed in the coating material for forming the surface layer by a dipping method, with its longitudinal direction aligned vertically. The dipping time for the dip coating was 9 seconds, and the withdrawal speed was an initial speed of 20 mm / sec and a final speed of 2 mm / sec, with the speed varying linearly with time. The resulting coated product was air-dried at room temperature for 30 minutes, then dried for 1 hour in a hot air circulation dryer set at 90°C, and further dried for 1 hour in a hot air circulation dryer set at 160°C, producing charging roller 1 according to the present invention. The 10-point average surface roughness of [charging roller 1] was 12.4 μm.

[0198] Manufacturing method of [Charging roller 2] In the manufacturing method of [Charged Roller 1], the conductive roughening particles were changed to cross-linked polymethyl methacrylate resin particles (product name: MBX-30, manufactured by Techpolymer) with an average particle size of 30 μm. Otherwise, [Charged Roller 2] was manufactured in the same manner as the manufacturing method of [Charged Roller 1]. The 10-point average roughness of [Charged Roller 2] was 28.5 μm.

[0199] ■Charging Roller Analysis <Measuring method for 10-point average surface roughness> Measurement was carried out using a surface roughness measuring instrument (product name: SE-3500, manufactured by Kosaka Laboratory Co., Ltd.) in accordance with the surface roughness standard of JIS B 0601-1994. The rubber part of the charging roller was divided into four parts longitudinally and four parts circumferentially, resulting in 16 areas, each of which was measured at 16 randomly selected points, and the arithmetic mean value was calculated. The measurement conditions were a cutoff value of 0.8 mm and an evaluation length of 8 mm.

[0200] [evaluation] [Examples 1 to 75 and Comparative Examples 1 to 23] The transferability (residual toner density) was evaluated using a modified Canon LBP7700C laser beam printer. The evaluation machine and software were modified to increase the rotation speed of the developing roller to 360 mm / sec. The toner cartridge was loaded with the prepared toner, and the prepared photoreceptor and charging roller were attached. The toner cartridge was then left in a high temperature and high humidity (30°C / 80%RH) environment (HH environment) for 24 hours. After leaving the toner cartridge in this environment for 24 hours, it was installed in a modified Canon LBP7700C laser beam printer.

[0201] To evaluate transferability, 10,000 sheets of A4 paper were printed in landscape orientation with a 5.0% coverage image centered on each side with 50 mm margins under a high-temperature environment. Evaluation was performed after 10,000 sheets had been printed. To evaluate transferability, a solid image was printed, and residual toner remaining on the photoreceptor after the solid image was formed was removed by taping it off with transparent polyester adhesive tape. The density difference was calculated by subtracting the density of the paper with only the adhesive tape attached from the density of the paper with the removed adhesive tape attached. Density measurements were performed at five locations on the photoreceptor after the solid image was formed, and the average value was calculated. The following evaluation was then performed based on the density difference. The density was measured using an X-Rite color reflection densitometer (X-rite 500 Series, manufactured by X-rite Co., Ltd.) A rating of C or higher was considered to be good. (Evaluation criteria) A: Density difference is less than 0.030 B: Density difference is 0.030 or more and less than 0.050 C: Density difference is 0.050 or more and less than 0.100 D: Density difference is 0.100 or more The evaluation results are shown in Tables 9 and 10 below.

[0202] [Table 9]

[0203] [Table 10] [Explanation of symbols]

[0204] 101 Electrophotographic photoreceptor 102 axes 103 Charging means 104 Exposure light 105 Developing means 106 Transcription means 107 Transfer material 108 Fixing means 109 Cleaning means 110 Pre-exposure light 111 Process cartridge 112 Guidance means< / ftir>

Claims

1. A process cartridge that is detachably mountable to a main body of an electrophotographic apparatus, the process cartridge has an electrophotographic photosensitive member, a toner, and a developing member that supplies the toner to the electrophotographic photosensitive member, the electrophotographic photoreceptor has a surface layer containing a (meth)acrylic resin having a urethane structure, the toner comprises toner particles and hydrotalcite particles as an external additive; In a filter fitting analysis in a STEM-EDS analysis, the hydrotalcite particles contain fluorine. A process cartridge characterized by:

2. 2. The process cartridge according to claim 1, wherein the surface layer of the electrophotographic photosensitive member has an elastic deformation rate of 45% or more.

3. 3. The process cartridge according to claim 1, wherein the hydrotalcite particles contain magnesium and aluminum in a filter fitting analysis in a STEM-EDS analysis.

4. 4. The process cartridge according to claim 1, wherein fluorine is present inside the hydrotalcite particles in line analysis by STEM-EDS analysis.

5. 5. The process cartridge according to claim 1, wherein, when an elastic deformation rate of the surface layer of the electrophotographic photosensitive member is η [%] and a content ratio of the hydrotalcite particles in the toner is q [% by mass], η and q satisfy a relationship represented by the following formula (A): 100≦η / q≦300 Formula (A)

6. the process cartridge has a charging member, the charging member has a conductive support and a conductive layer provided on the outer peripheral surface of the conductive support, 6. The process cartridge according to claim 1, wherein the charging member has an outer peripheral surface having a ten-point average surface roughness Rz of 5 μm or more and 20 μm or less.

7. An electrophotographic apparatus comprising the process cartridge according to any one of claims 1 to 6.

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