Process cartridge and electrophotographic apparatus

Abstract

To stabilize the amount of toner supplied from a toner supply roller to a developing roller to prevent the occurrence of a banding image.SOLUTION: A process cartridge 70 has a photoreceptor unit 26 and a developing unit 4. The developing unit 4 has a developing roller 22 that rotates in contact with the photoreceptor drum 1, and a toner supply roller 34 that rotates in contact with the developing roller 22. The direction of movement of a surface of the developing roller 22 and the direction of movement of a surface of the toner supply roller 34 are opposite to each other at a position where the rollers are in contact with each other. The developing roller and the toner supply roller are configured to rotate while satisfying a specific speed ratio. The surface of the developing roller 22 is a surface of an elastic layer. The toner supply roller 34 has a shaft body and a resin layer provided on an outer peripheral surface. The photoreceptor drum 1 has a surface layer containing polyarylate resin having a structural unit represented by the specific formula (A1) and a structural unit represented by the specific formula (A2).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 designed to have longer life spans. However, in the electrophotographic process, longer life spans tend to cause various problems. Therefore, various efforts have been made to address the various problems that come with longer life spans. Among the above-mentioned problems is one caused by changes in the surface conditions of the toner supply roller, developing roller, and electrophotographic photosensitive member (hereinafter simply referred to as "photosensitive member") mounted in the electrophotographic device due to repeated use of the electrophotographic device. When the surface conditions of the toner supply roller, developing roller, and photosensitive member change, the contact state between the toner supply roller and developing roller, and between the developing roller and photosensitive member, becomes unstable. When the contact state becomes unstable, image defects such as streaky unevenness tend to occur. Hereinafter, an electrophotographic image with streaky unevenness may be referred to as a "banding image."

[0003] In order to solve these problems, various improvements have been made to the configuration of the developing roller and the toner supply roller that supplies toner to the developing roller. Patent Document 1 describes a developing device in which the developer supply roller has a hollow core along all or part of its central axis. The hollow core of the developer supply roller makes it more susceptible to deformation due to stress applied to its circumferential surface. This prevents the contact pressure between the developing roller and the developer supply roller from becoming too high, thereby suppressing the occurrence of banding images caused by increased driving torque of the developing roller. Patent Document 2 describes an image forming apparatus that satisfies the following conditions. First, the amount of water-washed transfer of inorganic silicon fine particles on the surface of toner particles is 0.20 mass% or less. Also, the range of the peripheral speed ratio, which is the ratio of the peripheral speed of the developer carrier to the peripheral speed of the image carrier, is 120% to 300%. Furthermore, the dark potential Vd of the image carrier and the bias Vb applied to the regulating member that regulates the developer satisfy the relationship Vd < Vb. In Patent Document 2, by controlling the release of the external additive with the above configuration, the image flow is suppressed. As a result, it is possible to suppress an increase in the tackiness of the photosensitive member surface due to the adhesion of discharge products caused by image flow and moisture in the atmosphere, and to keep the surface state of the photosensitive member stable. In order to stably form high-quality images even during long-term use, the amount of toner supplied from the toner supply roller to the developing roller needs to be stable between the developing roller and the toner supply roller that supplies toner to the developing roller. In order to stabilize the amount of toner supplied from the toner supply roller to the developing roller, it is effective to adopt a configuration in which the rotation directions of the developing roller and the toner supply roller are opposite to each other at the rubbing portion (hereinafter referred to as the "counter configuration").

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] According to the studies of the present inventors, in the technologies described in Patent Documents 1 and 2, when a counter configuration is adopted to stabilize the amount of toner supplied from the toner supply roller to the developing roller, the coefficient of kinetic friction at the contact portion between the developing roller and the photosensitive member may increase. And, the problem was that image defects such as the occurrence of banding images occurred due to this increase in the coefficient of kinetic friction.

[0006] Therefore, an object of the present invention is to provide a process cartridge that can form high-quality electrophotographic images by stabilizing the amount of toner supplied from the toner supply roller to the developing roller and further suppressing the occurrence of banding images. [Means for solving the problem]

[0007] The above object can be achieved by the present invention as follows: That is, the process cartridge according to the present invention is a process cartridge that is detachably mountable to the main body of an electrophotographic apparatus, and the process cartridge includes an electrophotographic photosensitive member, and a developing roller for developing an electrostatic latent image formed on the surface of the electrophotographic photosensitive member; And, a toner supply roller that is disposed in contact with the developing roller and supplies toner to the developing roller; a driving force receiving portion that receives a driving force for driving the toner supply roller, a first driving force transmitting portion that transmits the driving force received by the driving force receiving portion to the toner supply roller, and a second driving force transmitting portion that transmits the driving force generated by driving the toner supply roller to the developing roller; The developing roller and the toner supply roller have a configuration in which the direction of movement of the surface of the developing roller and the direction of movement of the surface of the toner supply roller during operation are opposite to each other at the contact position between the developing roller and the toner supply roller, and R represented by the following formula (E1) is 1.2≦R≦1. 3 It is configured to rotate by filling R=V RS / V D (E1) (In formula (E1), V RS represents the absolute value of the peripheral speed [m / s] of the toner supply roller, and V D represents the absolute value of the peripheral speed [m / s] of the developing roller. the surface of the developing roller is the surface of an elastic layer, the MD-1 hardness of the surface of the developing roller is 50° or more and 55° or less, The toner supply roller has a shaft and a resin layer provided on the outer peripheral surface of the shaft, and the electrophotographic photosensitive member , Po It has a surface layer containing acrylate resin. the polyarylate resin has a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2), and the molar ratio of the structural unit represented by the following formula (A1) to the structural unit represented by the following formula (A2) in the surface layer of the electrophotographic photosensitive member is within a range of 1.4:0.7 to 1.2:0.9 (structural unit represented by formula (A1):structural unit represented by formula (A2)). It is characterized by the fact that [ka] [ka] [Effects of the Invention]

[0008] According to the present invention, a process cartridge can be provided that can form high-quality electrophotographic images by stabilizing the amount of toner supplied from the toner supply roller to the developing roller and further suppressing the occurrence of banding images caused by an increase in the dynamic friction coefficient between the developing roller and the photosensitive member. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic cross-sectional view of a process cartridge according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic view showing a drive mechanism for a toner supply roller and a developing roller according to an embodiment of the present invention. [Figure 3] FIG. 2 is a schematic view showing a drive mechanism for a toner supply roller and a developing roller according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below with reference to preferred embodiments. The present invention relates to a process cartridge that is detachably mountable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member and a developing roller for developing an electrostatic latent image formed on the surface of the electrophotographic photosensitive member; And, a toner supply roller that is disposed in contact with the developing roller and supplies toner to the developing roller; a driving force receiving portion that receives a driving force for driving the toner supply roller, a first driving force transmitting portion that transmits the driving force received by the driving force receiving portion to the toner supply roller, and a second driving force transmitting portion that transmits the driving force generated by driving the toner supply roller to the developing roller; The developing roller and the toner supply roller have a configuration in which the direction of movement of the surface of the developing roller and the direction of movement of the surface of the toner supply roller during operation are opposite to each other at the contact position between the developing roller and the toner supply roller, and R represented by the following formula (E1) is 1.2≦R≦1. 3 It is configured to rotate by filling R=V RS / V D (E1) (In formula (E1), V RSrepresents the absolute value of the peripheral speed [m / s] of the toner supply roller, and V D represents the absolute value of the peripheral speed [m / s] of the developing roller. the surface of the developing roller is the surface of an elastic layer, the MD-1 hardness of the surface of the developing roller is 50° or more and 55° or less, The toner supply roller has a shaft and a resin layer provided on the outer peripheral surface of the shaft, and the electrophotographic photosensitive member , Po It has a surface layer containing acrylate resin. the polyarylate resin has a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2), and the molar ratio of the structural unit represented by the following formula (A1) to the structural unit represented by the following formula (A2) in the surface layer of the electrophotographic photosensitive member is within a range of 1.4:0.7 to 1.2:0.9 (structural unit represented by formula (A1):structural unit represented by formula (A2)). The present invention relates to a process cartridge characterized by: [ka] [ka]

[0011] The inventors have studied the matter and found that the prior art has not provided sufficient countermeasures against the increase in the coefficient of dynamic friction between the developing roller and the photosensitive member that accompanies changes in the surface of the developing roller. Therefore, the inventors have studied and optimized the combination of the configuration of the developing roller and toner supply roller with the surface material of the photoreceptor. As a result, they have found that the above problem can be solved by adopting the following configuration. First, the developing roller and the toner supply roller are configured so that the surface movement direction of the developing roller and the surface movement direction of the toner supply roller are opposite to each other at the contact position between the developing roller and the toner supply roller. Furthermore, the developing roller and the toner supply roller are configured so that R, as shown in the following formula (E1), satisfies the condition 1.2≦R≦1. 3 The rotor is configured to rotate when the rotor is filled with the R=V RS / V D Formula (E1) (In formula (E1), V RS represents the absolute value of the peripheral speed [m / s] of the toner supply roller, and V D represents the absolute value of the peripheral speed [m / s] of the developing roller.)

[0012] The surface of the developing roller is the surface of an elastic layer, the toner supply roller has a shaft and a resin layer provided on the outer peripheral surface of the shaft, and the photoreceptor has a surface layer containing a polyarylate resin having a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2). [ka] [ka]

[0013] The present inventors believe that the mechanism by which the above-mentioned problems can be solved with such a configuration is as follows. The developing roller and toner supply roller are configured in a counter-rotational configuration with R greater than 1, stabilizing the amount of toner supplied from the toner supply roller to the developing roller. However, when the developing roller and toner supply roller are configured in a counter-rotational configuration with R greater than 1, the friction between the developing roller and the toner supply roller is significantly affected. If friction with the toner supply roller reduces viscoelasticity and creates unstable areas on the surface of the developing roller, the coefficient of kinetic friction between the developing roller and the photosensitive drum increases when that area contacts the photosensitive drum. Furthermore, under the above configuration, the friction between the toner supply roller and the developing roller is significantly affected, and the surface of the developing roller is likely to heat up due to friction with the toner supply roller. In particular, if the surface of the developing roller is an elastic layer, the surface of the developing roller is pulled by contact with the toner supply roller, temporarily stretching the surface. After passing the contact point with the toner supply roller, the developing roller itself heats up, causing the surface of the developing roller to shrink due to entropy elasticity. At the same time, the friction with the toner supply roller reduces viscoelasticity in areas on the surface of the developing roller. When the portion of the developing roller surface that has become unstable due to the temperature rise comes into contact with the photosensitive member, the frictional state between the developing roller and the photosensitive member fluctuates, the coefficient of dynamic friction between the developing roller and the photosensitive member increases, and as a result, image defects such as banding occur.

[0014] Therefore, the present inventors have considered combining a photoreceptor having a surface layer containing a polyarylate resin having a structural unit represented by formula (A1) and a structural unit represented by formula (A2). On the one hand, the structural units represented by formula (A1) and formula (A2) contain ester moieties with highly electronegative oxygen atoms, and these ester moieties are polarized, resulting in a δ- charge. On the other hand, the methyl group of the trimethylcyclohexane structure present in the structural unit represented by formula (A2) is electron-donating, resulting in a δ+ charge. Therefore, a strong electrostatic attraction acts between the polymers, separate from the van der Waals forces, resulting in strong bonding between the polymers. Therefore, the polyarylate resin exhibits minimal change in response to external forces such as heat.

[0015] By combining the developing roller with a photoreceptor having a surface layer containing the polyarylate resin, even if a portion of the developing roller with an unstable surface condition comes into contact with the photoreceptor, the effect is less than when the developing roller comes into contact with a photoreceptor having a conventional surface layer, and as a result, an increase in the coefficient of dynamic friction between the developing roller and the photoreceptor can be suppressed.

[0016] As shown by the above mechanism, in the process cartridge of the present invention, the above-mentioned configurations of the developing roller and toner supply roller and the above-mentioned surface material of the photosensitive body have a synergistic effect, making it possible to achieve the effects of the present invention.

[0017] The configuration of the photosensitive member used in the process cartridge according to the present invention will be described in detail below.

[0018] [Electrophotographic photoreceptor] The photoreceptor used in the process cartridge according to the present invention has a surface layer containing a polyarylate resin having a structural unit represented by formula (A1) and a structural unit represented by formula (A2). A method for producing a photoreceptor includes preparing a coating liquid for each layer described below, coating the layers in the desired order, and drying the coating liquid. Examples of methods for applying the coating liquid include dip coating, spray coating, inkjet coating, roll coating, die coating, blade coating, curtain coating, wire bar coating, and ring coating. Among these, dip coating is preferred from the viewpoints of efficiency and productivity.

[0019] The support and each layer will be described below. <Support> In the present invention, the 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 which an aluminum support using aluminum is preferred. Furthermore, the resin or glass may be made conductive by mixing or coating it with a conductive material.

[0020] <Conductive layer> In the present invention, the photoreceptor may have a conductive layer 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. 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 the conductive particles, the surface 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 oxides thereof. The conductive particles may have a layered 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 a metal oxide such as tin oxide. When metal oxide particles are used as the conductive particles, the volume average particle size is preferably 1 nm or more and 500 nm or less, and more preferably 3 nm or more and 400 nm or less. 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. The 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. 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.

[0021] <Undercoat layer> In the photoreceptor used in the present invention, an undercoat layer may be provided on the support or the conductive layer. By providing an undercoat layer, the adhesion between layers can be improved and a charge injection blocking function can be imparted. The undercoat layer preferably contains a resin. Alternatively, the undercoat layer may be formed as a cured film by polymerizing a composition containing a monomer having a polymerizable functional group. 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. 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.

[0022] 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 additives. The 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. 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.

[0023] <Photosensitive layer> The photosensitive layer of the photoreceptor used in 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 has a photosensitive layer containing both a charge generation material and a charge transport material.

[0024] (1) Laminated photosensitive layer The laminated photosensitive layer has a charge generating layer and a charge transport layer.

[0025] (1-1) Charge generation layer The charge generating layer preferably contains a charge generating material and a resin. 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. 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. 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. The thickness of the charge generating layer is preferably 0.1 μm or more and 1 μm or less, and more preferably 0.15 μm or more and 0.4 μm or less. 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.

[0026] (1-2) Charge transport layer The charge transport layer preferably contains a charge transport material and a resin. 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. Examples of the resin include polyester resin, polycarbonate resin, acrylic resin, polystyrene resin, etc. Among these, polycarbonate resin and polyester 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.

[0027] 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. The 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. 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.

[0028] (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 transport material, a resin, and a solvent, forming a coating film from the coating solution, and drying the coating film. The charge generating material, charge transport material, and resin are the same as those exemplified in "(1) Multilayer Photosensitive Layer" above.

[0029] <Protective layer> In the photoreceptor used in the present invention, a protective layer may be provided on the photosensitive layer, which can improve durability. The protective layer preferably contains conductive particles and / or a charge transport material, and a resin. Examples of conductive particles include particles of metal oxides such as titanium oxide, zinc oxide, tin oxide, and indium oxide. 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. 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.

[0030] 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. 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. The 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. The protective layer can be formed by preparing a coating solution for the protective layer containing the above-mentioned materials and solvent, forming a coating film from the coating solution, and drying and / or curing the coating 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.

[0031] <Surface layer> In the photoreceptor used in the present invention, the surface layer contains a polyarylate resin having a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2). [ka] [ka]

[0032] The surface layer here refers to the portion of the photoreceptor that comes into contact with toner and various members during the electrophotographic process. The surface layer can be a protective layer, a charge transport layer, or a single-layer photosensitive layer, but from the viewpoint of achieving both cost reduction and basic electrical properties in the electrophotographic process, the surface layer is preferably a charge transport layer.

[0033] The polymer components recovered from the surface layer of the photoreceptor were dissolved in deuterated chloroform. 1 Obtained by subjecting to H-nuclear magnetic resonance (NMR) analysis 1 The H-nuclear magnetic resonance spectrum can have peaks at the following positions: 1 The H-nuclear magnetic resonance spectrum can have peaks at 8.97±0.02, 8.43±0.02, 7.67±0.02, 8.30±0.02, 1.71±0.03, 0.42±0.02, 1.01±0.02 ppm. 1 The presence of peaks at 8.97±0.02, 8.43±0.02, and 7.67±0.02 ppm in the H-nuclear magnetic resonance spectrum indicates the presence of an IPA (isophthalic acid) structure contained in formula (A1) or formula (A2). 1The presence of a peak at 8.30±0.02 in the H-nuclear magnetic resonance spectrum indicates the presence of a TPA (terephthalic acid) structure contained in formula (A1) or formula (A2). 1 The H-nuclear magnetic resonance spectrum has a peak at 1.71±0.03 ppm, which indicates the presence of the bisphenol A structure contained in formula (A1). 1 The H-nuclear magnetic resonance spectrum has peaks at 0.42±0.02 and 1.01±0.02 ppm, indicating the presence of the bisphenol TMC structure contained in formula (A2). 1 When the H-nuclear magnetic resonance spectrum has all of the peaks described above, it indicates that the compound contains a compound having a structural unit represented by formula (A1) and a structural unit represented by formula (A2).

[0034] A specific method for recovering the polymer component from the surface layer of the photoreceptor and analyzing it with NMR will be described below. <Recovery of polymer components from the surface layer> The recovery of the polymer component from the surface layer of the photoreceptor is carried out by reprecipitation of the resin in the surface layer in the following manner. 1. Cut the photoconductor The photoreceptor is cut using a jigsaw at a position 10 cm from the end of the photoreceptor in the generatrix direction. 2. Clean the inside of the cut 10cm photoconductor Wipe the inside of the photoreceptor with Silbon paper soaked in chloroform. 3. Elution of the surface layer Immerse 3 cm of the cut end of the photoreceptor in chloroform. Specifically, approximately 60 cc of chloroform is placed in a 100 mL beaker and the sample is immersed at room temperature for 5 minutes. 4. Concentrate (concentrated liquefaction) Concentrate to 2 mL using a rotary evaporator. 5. Re-sedimentation Prepare 50 mL of a methanol / acetone mixture (volume ratio 1:1), and add the entire amount of the above concentrated solution dropwise while stirring. 6. Filter Set a filter paper (No. 5C-40, manufactured by Kiriyama Seisakusho Co., Ltd.) on Kiriyama Rotor (SU-40, manufactured by Kiriyama Seisakusho Co., Ltd.) and perform suction filtration. 7. Dry Collect the residue on the filter paper with a spatula and vacuum dry it (70 °C for 1 hour).

[0035] <NMR Analysis> · Preparation of measurement sample Dissolve 20 mg of the sample in 1 g of deuterated chloroform containing the reference substance tetramethylsilane, and transfer the entire amount 1 to a tube for 1H-NMR analysis. As the deuterated chloroform, for example, deuterated chloroform (manufactured by Sigma-Aldrich Japan Co., Ltd., chloroform-d, product number 612200) can be used. Also, 1 As the tube for 1H-NMR analysis, an NMR tube (manufactured by Norell, ST500-7, product number S3010) can be used. · NMR spectrum measurement Apparatus: AVANCE500 manufactured by Bruker Conditions: Automatic measurement by proton NMR and ICON-NMR Number of integrations: 32 times Reference peak: Set the methyl group peak of tetramethylsilane to 0 ppm

[0036] The molar ratio of the structural unit represented by formula (A1) and the structural unit represented by formula (A2) in the surface layer of the photoreceptor teeth [[ID=​32]]、 From the viewpoint of mechanical strength, 1.4:0.7 to 1.2:0.9 (structural unit represented by formula (A1): structural unit represented by formula (A2)) is in the range of do. Also, from the viewpoint of suppressing an increase in the dynamic friction coefficient between the developing roller and the photoreceptor, it is preferable that the content ratio of the polyarylate resin in the surface layer of the photoreceptor satisfies the following conditions. That is, the content ratio of the polyarylate resin having the structural unit represented by formula (A1) and the structural unit represented by formula (A2) with respect to the total mass of the surface layer is preferably 15% by mass or more, and more preferably 20% by mass or more.

[0037] [Developing Roller] The developing roller used in the present invention must have an elastic layer on its surface, which is an elastic roller configured by providing a conductive elastic rubber layer having a predetermined volume resistivity as an elastic layer around a conductive base, such as a metal core. The configuration of the developing roller according to one aspect of the present disclosure will be described in detail below.

[0038] <Conductive substrate> The conductive substrate may be a cylindrical or hollow cylindrical conductive mandrel. The mandrel may be cylindrical or hollow cylindrical in shape and may be made of the following conductive materials. That is, examples of the conductive material include metals or alloys such as aluminum, copper alloys, and stainless steel; iron plated with chromium or nickel; and conductive synthetic resins. A known adhesive may be applied to the surface of the conductive substrate as appropriate in order to improve adhesion to an elastic layer or the like provided on its outer periphery.

[0039] <Elastic layer> The elastic layer may include multiple layers with different properties depending on the required function. The elastic layer is preferably formed by molding a rubber material. Examples of rubber materials include ethylene-propylene-diene copolymer rubber (EPDM), acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), natural rubber (NR), isoprene rubber (IR), styrene-butadiene rubber (SBR), fluororubber, silicone rubber, epichlorohydrin rubber, NBR hydride, and urethane rubber. These materials may be used alone or in combination of two or more. Depending on the required properties, the surface of the elastic layer may be subjected to commonly known surface treatments such as ultraviolet rays, electron beams, or impregnation treatment. In order to suppress the change in the dynamic friction coefficient between the developing roller and the photosensitive member, the MD-1 hardness of the outer surface of the developing roller measured at a temperature of 23°C is: 50° More than 55° do.

[0040] The elastic layer can be made conductive by blending a conductivity-imparting agent such as an electronically conductive substance or an ionic conductive substance. Examples of electronically conductive materials include conductive carbon, such as carbon blacks such as Ketjenblack EC and acetylene black; rubber carbons such as SAF (Super Abrasion Furnace), ISAF (Intermediate SAF), HAF (High Abrasion Furnace), FEF (Fast Extruding Furnace), GPF (General Purpose Furnace), SRF (Semi-Reinforcing Furnace), FT (Fine Thermal), and MT (Medium Thermal); oxidation-treated carbons for color (ink); and metals such as copper, silver, and germanium and their metal oxides. Among these, conductive carbons are preferred because they allow easy control of conductivity with a small amount. Examples of the ionically conductive substance include inorganic ionically conductive substances such as sodium perchlorate, lithium perchlorate, calcium perchlorate, and lithium chloride; and organic ionically conductive substances such as modified aliphatic dimethylammonium ethosulfate and stearylammonium acetate. These conductivity-imparting agents are blended in an appropriate amount according to the conductivity required for the elastic layer.

[0041] The elastic layer may further contain various additives, as needed, such as particles, conductive agents, plasticizers, fillers, extenders, crosslinking agents, crosslinking accelerators, vulcanization aids, crosslinking aids, acid acceptors, cure inhibitors, antioxidants, and antioxidants. These optional components may be blended in amounts that do not impair the features of the present disclosure. Examples of crosslinking agents include sulfur-based crosslinking agents such as powdered sulfur, oil-treated powdered sulfur, precipitated sulfur, colloidal sulfur, and dispersible sulfur, as well as organic sulfur-containing compounds such as tetramethylthiuram disulfide and N,N-dithiobismorpholine. Considering the need to impart good rubber properties, the blending ratio of sulfur is preferably 0.5 parts by mass or more and 2.0 parts by mass or less per 100 parts by mass of the total rubber material. Furthermore, when using an organic sulfur-containing compound as a crosslinking agent, it is preferable to adjust the amount of sulfur in the molecule to fall within the above range. Examples of fillers that can be used include zinc oxide, silica, carbon black, talc, calcium carbonate, magnesium carbonate, and aluminum hydroxide. By incorporating these fillers, the mechanical strength of the binder resin can be expected to be improved. Furthermore, by using conductive carbon black, which functions as an electronic conductor, as the filler, electronic conductivity can be imparted to the electrophotographic member, as described above. The filler is incorporated in an appropriate amount depending on the properties required for the molded product.

[0042] Next, the configuration of the toner supply roller used in the present invention will be described in detail. [Toner supply roller] The toner supply roller used in the present invention must have a conductive shaft and a resin layer on the shaft. The structure of the toner supply roller used in the present invention will be described in detail below.

[0043] <Shaft> The shaft functions as a support member for the toner supply roller and as an electrode. The shaft is made of a conductive material such as a metal or alloy such as aluminum, copper alloy, or stainless steel; iron plated with chromium or nickel; or conductive synthetic resin. The shaft is either solid or hollow cylindrical.

[0044] <Resin layer> From the viewpoint of strength, the resin layer preferably contains a polyurethane resin (crosslinked urethane resin) as a binder resin, which will be described later. Furthermore, the resin layer is preferably a foamed layer having voids capable of storing toner particles within the layer so that the toner particles can be uniformly supplied to the surface of the developing roller as a toner supply roller. Examples of the voids include a large number of through-holes and non-through-holes. Another example of the voids may be a porous layer in which bubbles are connected to each other (open cells). The foamed layer containing the cross-linked urethane resin is preferably in an open cell state with large voids. The physical properties of the surface of such a foamed layer having voids, such as the average cell diameter, number of cells, air permeability, and density of the entire layer, are preferably determined by the developer. foam The physical properties of the foam layer are not particularly limited, but it is preferable that the foam layer has values ​​within the following ranges. Average surface cell diameter: 100 μm or more and 500 μm or less; Number of cells: 50 to 300 cells / inch; Ventilation rate: 0.5L / min or more and 3.0L / min or less; Density: 0.05g / cm 3 More than 0.20g / cm 3 below.

[0045] <Cross-linked urethane resin> The cross-linked urethane resin is a reaction product of a polyol and a compound having an isocyanate group. Examples of polyols used to synthesize the cross-linked urethane resin of the toner supply roller of the present invention include polyester polyols, polyether polyols, acrylic polyols, polycarbonate polyols, and polycaprolactone polyols. Among these, polyether polyols are preferred because the cross-linked urethane resin has flexibility.

[0046] Examples of polyether polyols include polyethylene glycol, polypropylene glycol, poly-1,4-butanediol, poly-1,5-pentanediol, polyneopentyl glycol, poly-3-methyl-1,5-pentanediol, poly-1,6-hexanediol, poly-1,8-octanediol, and poly-1,9-nonanediol. Among these, polypropylene glycol, poly-1,4-butanediol, poly-1,5-pentanediol, polyneopentyl glycol, poly-3-methyl-1,5-pentanediol, and poly-1,6-hexanediol are preferred from the viewpoint of suppressing an increase in hardness. Examples of polyester polyols include the following: Polyester polyols obtained by the condensation reaction of a diol component such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, or 1,9-nonanediol, or a triol component such as trimethylolpropane, with a dicarboxylic acid such as adipic acid, suberic acid, sebacic acid, phthalic anhydride, terephthalic acid, or hexahydroxyphthalic acid. Among these, polyester polyols obtained by the condensation reaction of a diol component such as propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, or 1,6-hexanediol with a dicarboxylic acid such as adipic acid, suberic acid, or sebacic acid are preferred from the viewpoint of suppressing an increase in hardness.

[0047] Examples of polycaprolactone polyols include poly-ε-caprolactone and poly-γ-caprolactone.

[0048] Examples of polycarbonate polyols include polycarbonate polyols obtained by condensation reaction of a diol component such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, or 1,9-nonanediol with a dialkyl carbonate such as phosgene or dimethyl carbonate, or a cyclic carbonate such as ethylene carbonate. Among these, polycarbonate polyols obtained by condensation reaction of a diol component such as neopentyl glycol, 3-methyl-1,5-pentanediol, 1,5-pentanediol, 1,6-hexanediol, or 1,8-octanediol with a dialkyl carbonate such as dimethyl carbonate are preferred from the viewpoint of suppressing an increase in hardness. If necessary, these polyol components may be chain-extended in advance with an isocyanate compound such as 2,4-tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), or isophorone diisocyanate (IPDI) to form a prepolymer.

[0049] <Isocyanate compounds> The isocyanate compound is not particularly limited, but examples thereof include aliphatic polyisocyanates such as ethylene diisocyanate and 1,6-hexamethylene diisocyanate (HDI); alicyclic polyisocyanates such as isophorone diisocyanate (IPDI), cyclohexane-1,3-diisocyanate, and cyclohexane-1,4-diisocyanate; aromatic isocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), polymeric diphenylmethane diisocyanate, xylylene diisocyanate, and naphthalene diisocyanate; and copolymers thereof, isocyanurates, TMP adducts, biurets, and block products thereof. Among these, aromatic isocyanates such as tolylene diisocyanate and diphenylmethane diisocyanate are preferred. The polyol component and the isocyanate compound are preferably mixed so that the ratio (molar ratio) of isocyanate groups in the isocyanate compound to hydroxyl groups in the polyol component is 1.0 to 2.0. If the mixing ratio is within the above range, it is possible to suppress the remaining unreacted components.

[0050] <Crosslinking agent> A crosslinking agent is preferably included as a component constituting the crosslinked urethane resin. Examples of crosslinking agents include tri- or higher functional isocyanates and tri- or higher functional polyols, which can be used to form a crosslinked structure. Alternatively, a known crosslinking agent that is optimal for urethane resins may be used. Examples include amine-based crosslinking agents such as ethylenediamine, and imide-based crosslinking agents such as carbodiimide.

[0051] <Other components in the resin layer> The resin layer may contain a conductive filler as needed, provided that the effect of the present invention is not impaired. The resin layer preferably contains an electronically conductive filler. As the conductive filler, carbon black, aluminum, copper, and other conductive metals can be used. Among these, carbon black is particularly preferred because it is relatively easy to obtain and has high conductivity and reinforcing properties. The resin layer can contain catalysts, foaming agents, foam stabilizers, and other auxiliary agents as needed. The catalyst is not particularly limited and can be appropriately selected from various conventionally known catalysts. Examples include amine catalysts (triethylenediamine, bis(dimethylaminoethyl)ether, N,N,N',N'-tetramethylhexanediamine, 1,8-diazabicyclo(5.4.0)undecene-7, 1,5-diazabicyclo(4.3.0)nonene-5, 1,2-dimethylimidazole, N-ethylmorpholine, N-methylmorpholine, etc.), organometallic catalysts (tin octoate, tin oleate, dibutyltin dilaurate, dibutyltin diacetate, tetra-i-propoxytitanium, tetra-n-butoxytitanium, tetrakis(2-ethylhexyloxy)titanium, etc.), and acid salt catalysts (carboxylates, formates, octoates, borates, etc.) that reduce the initial activity of the amine catalysts and organometallic catalysts. The catalysts may be used alone or in combination. The foaming agent is not particularly limited, and can be appropriately selected from various conventionally known foaming agents. In particular, water is preferably used as a foaming agent because it reacts with polyisocyanate to generate carbon dioxide gas. Furthermore, the use of other foaming agents in combination with water does not detract from the gist of the present invention. The foam stabilizer is not particularly limited and can be appropriately selected from various conventionally known foam stabilizers. Other additives, such as crosslinking aids, flame retardants, colorants, ultraviolet absorbers, and antioxidants, may be used as needed within the range that does not impair the effects of the present invention.

[0052] [Process cartridges, electrophotographic devices] The process cartridge according to the present invention is a process cartridge detachably mountable to the main body of an electrophotographic apparatus, and is characterized by comprising the electrophotographic photosensitive member, developing roller, and toner supply roller described above, wherein the developing roller is configured to develop an electrostatic latent image formed on the surface of the photosensitive member, and the toner supply roller is disposed in contact with the developing roller and configured to supply toner to the developing roller. An electrophotographic apparatus according to the present invention is characterized by having the above process cartridge.

[0053] FIG. 1 shows an example of a main cross section of a process cartridge 70 equipped with a photosensitive member, a developing roller, and a toner supply roller. The process cartridge 70 includes a photosensitive unit 26 and a developing unit 4. The photosensitive unit 26 includes a photosensitive drum 1, a charging roller 2, and a cleaning member 6. The developing unit 4 includes a developing roller 25 and a toner supply roller 34. The aforementioned charging roller 2 and cleaning member 6 are arranged around the photosensitive drum 1. The cleaning member 6 is composed of an elastic member 7 formed of a rubber blade and a cleaning support member 8. The tip of the elastic member 7 is arranged to abut against the photosensitive drum 1 in the counter direction to the rotation direction. The toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 falls into a removed toner chamber 27. The photosensitive drum 1 is rotated in accordance with the image forming operation by transmitting the driving force of a main body driving motor (not shown) serving as a driving source to the photosensitive unit . The charging roller 2 is rotatably attached to the photosensitive unit 26 via a charging roller bearing, and is pressed toward the photosensitive drum 1 by a charging roller pressure member and comes into contact with the photosensitive drum 1, thereby rotating in conjunction with the rotation of the photosensitive drum 1.

[0054] The developing unit 4 has a developing roller 25 that rotates in contact with the photosensitive drum 1, and a developing frame 31 that supports the developing roller 25. Around the developing roller 25, a toner supply roller 34 that rotates in the direction of arrow C in contact with the developing roller 25, and a developing blade 35 that regulates the toner layer on the developing roller 25 are arranged. The developing roller 25 and the photosensitive drum 1 rotate so that their surfaces move in the same direction at the opposing portion (contact portion). A predetermined DC bias is applied to the developing roller 25, and the toner is negatively charged by frictional charging. At the developing portion where the toner contacts the photosensitive drum 1, the toner transfers only to the bright potential portion due to the potential difference, thereby visualizing the electrostatic latent image.

[0055] The developing blade 35 is disposed below the developing roller 25 in the plane of FIG. 1 and abuts against the developing roller 25 in the counter direction, regulating the coating amount of the toner supplied by the toner supply roller 34 and imparting an electric charge. The developing blade 35 may be composed of a flexible plate-like member and a developing blade support that fixes the plate-like member. The developing blade 35 may also be composed of an elastic plate made of stainless steel (SUS). The toner is frictionally charged by the friction between the developing blade 35 and the developing roller 25, imparting an electric charge and simultaneously regulating the layer thickness. A predetermined voltage is applied to the developing blade 35 from a blade bias power supply (not shown) to stabilize the toner coating.

[0056] The toner supply roller 34 contacts the developing roller 25 at a nip N. In the present invention, the toner supply roller 34 and the developing roller 25 are configured so that, during operation (rotation), the surface of the toner supply roller 34 moves in the nip N in the opposite direction to the surface of the developing roller 25 in the nip N (counter configuration). That is, the surface of the developing roller 25 moves in the opposite direction to the surface of the toner supply roller 34 at the contact position with the toner supply roller 34. The toner supply roller 34 and the developing roller 25 are in contact with each other with a predetermined intrusion amount, i.e., the amount of recession ΔE that the toner supply roller 34 is recessed by the developing roller 25. The toner supply roller 34 and the developing roller 25 must rotate in opposite directions at the nip N with the following peripheral speed difference: That is, the developing roller 25 and the toner supply roller 34 are configured to rotate such that R, as shown in the following formula (E1), satisfies 1.2≦R≦1.5. R=V RS / V D (E1) (In formula (E1), V RS represents the absolute value of the peripheral speed [m / s] of the toner supply roller 34, and V D represents the absolute value of the peripheral speed of the developing roller [m / s].) This operation recovers the remaining toner on the developing roller 25 while supplying toner to the developing roller 25. At this time, by adjusting the potential difference between the toner supply roller 34 and the developing roller 25, the amount of remaining toner recovered on the developing roller 25 and the amount of toner supplied to the developing roller 25 can be adjusted.

[0057] The toner supply roller 34 includes, for example, a conductive support as a shaft body and a foam layer supported by the conductive support. Specifically, the conductive support may be a core metal electrode with an outer diameter of φ5 (mm), and a foamed urethane layer as a foamed layer made of open-cell foam (open cells) around the core metal electrode, in which cells are connected to each other, may be provided, and the roller rotates in the direction of C in the figure during operation. By making the urethane surface layer open-cell foam, a large amount of toner can penetrate into the toner supply roller 34. The resistance of the toner supply roller 34 is, for example, 1×10 9It may be Ω.

[0058] The amount of penetration of the toner supply roller 34 into the developing roller 25, that is, the amount of depression ΔE by which the toner supply roller 34 is made into a depression by the developing roller 25, can be set to 1.0 mm. Here, we will explain how to measure the resistance of the toner supply roller 34. The toner supply roller 34 is brought into contact with an aluminum sleeve with a diameter of 30 mm so that the penetration amount, which will be described later, is 1.5 mm. By rotating this aluminum sleeve, the toner supply roller 34 is rotated at 30 rpm relative to the aluminum sleeve. Next, a DC voltage of -50 V is applied to the developing roller 25. At this time, a 10 kΩ resistor is provided on the ground side, and the current is calculated by measuring the voltage across the resistor, and the resistance of the toner supply roller 34 is calculated. 34 The surface cell diameter can be set to, for example, 50 μm to 1000 μm. Here, cell diameter refers to the average diameter of foam cells in an arbitrary cross section. First, the area of ​​the largest foam cell is measured from an enlarged image of the arbitrary cross section, and the maximum cell diameter is obtained by converting this area into a diameter equivalent to a perfect circle. Then, foam cells that are half or less of this maximum cell diameter are eliminated as noise, and the remaining individual cell areas are similarly converted to obtain the average cell diameter.

[0059] The toner supplied from the toner supply roller 34 to the surface of the developing roller 25 is frictionally charged by the friction between the developing blade 35 and the developing roller 25, and the layer thickness is regulated while the toner is given an electric charge. The toner is then transported to the contact area (developing section) between the photosensitive drum 1 and the developing roller 25, and transferred only to the light potential area. The remaining toner remaining on the surface of the developing roller 25 returns to the developer container, is collected from the surface of the developing roller 25 by the toner supply roller 34, and is stored inside the toner supply roller 34.

[0060] The structure for driving the developing roller 25 and the toner supply roller 34 includes a driving force receiving portion, a first driving force transmitting portion, and a second driving force transmitting portion. do.Here, the driving force receiving portion is configured to receive a driving force for driving the toner supply roller 34. The first driving force transmitting portion is configured to transmit the driving force received by the driving force receiving portion to the toner supply roller 34. The second driving force transmitting portion is configured to transmit the driving force generated by the driving of the toner supply roller 34 to the developing roller 25. Since the rotational drive of the developing roller 25 is indirectly performed via the second driving force transmitting portion in response to the input of driving force from an external source, the second driving force transmitting portion absorbs sudden fluctuations in frictional force, thereby suppressing instability in the toner coating amount on the developing roller 25 (Reference Patent Document: JP 2014-134787 A). Specifically, since the developing roller 25 contacts both the toner supply roller 34 and the photosensitive drum 1, sudden fluctuations in frictional force occurring between the developing roller 25 and the photosensitive drum 1 affect the rotation of the toner supply roller 34, which contacts the developing roller 25. This may result in instability in the toner coating amount supplied to the developing roller 25 by the toner supply roller 34. The structureIn this configuration, the toner supply roller 34 is first driven by an external driving force, and then the developing roller 25 is driven via the second driving force transmission unit. Therefore, even if a sudden change in frictional force occurs between the developing roller 25 and the photosensitive drum 1, the toner supply roller 34 is driven by an external driving force that is not affected by the frictional force change, and the second driving force transmission unit absorbs the frictional force change. This allows the toner supply roller 34 to stably supply toner to the developing roller 25. The above configuration, which prevents sudden frictional force changes from causing instability in the toner coat amount, is suitable for suppressing banding during repeated use in the present invention. The second driving force transmission unit may include a third driving force transmission unit, a fourth driving force transmission unit, and a fifth driving force transmission unit. Here, the third driving force transmission unit is provided at the end of the shaft of the toner supply roller 34 and is configured to transmit the driving force generated by the driving of the toner supply roller 34 to the fourth driving force transmission unit. The fourth drive force transmission unit is configured to be driven by the drive force received from the third drive force transmission unit, thereby transmitting the drive force to the fifth drive force transmission unit. The fifth drive force transmission unit is provided at an end of the shaft body of the developing roller 25, and is configured to receive the drive force from the fourth drive force transmission unit to drive the developing roller 25.

[0061] FIG. 2 is a schematic diagram showing a specific example of a preferred configuration for driving the developing roller and toner supply roller described above. The driving force input to coupling (driving force receiving portion) 101 is transmitted to driving force transmission member 103 through intermediate body 102, thereby rotating toner supply roller 134. Here, the combination of intermediate body 102 and driving force transmission member 103 corresponds to the first driving force transmission portion described above. The rotational driving force transmitted to toner supply roller 134 is transmitted to gear (third driving force transmission portion) 104a, gear (fourth driving force transmission portion) 104b, and gear (fifth driving force transmission portion) 104c in this order, thereby rotating developing roller 125. Here, the configuration consisting of the combination of gears 104a, 104b, and 104c corresponds to the second driving force transmission portion described above. That is, gear 104a is provided at the end of shaft body 105 of toner supply roller 134 and transmits the driving force generated by the driving of toner supply roller 134 to gear 104b. Next, gear 104b is driven by the driving force received from gear 104a and transmits the driving force to gear 104c. Gear 104c is located at the end of the shaft member 106 of the developing roller 125 and receives the driving force from gear 104b to drive the developing roller 125. This allows the driving force generated by the driving of the toner supply roller 134 to be transmitted to the developing roller 125. In the example shown in FIG. 2, there is play in the meshing portions between gears 104a, 104b, and 104c, so that sudden fluctuations in frictional force occurring between the developing roller 125 and the photosensitive drum can be absorbed. Furthermore, the driving force transmitted from the outside to the toner supply roller 134 via the coupling 101, the intermediate member 102, and the driving force transmission member 103 is not affected by the frictional force fluctuations, so the toner supply roller 134 is driven stably. This suppresses fluctuations in the amount of toner supplied from the toner supply roller 134 to the developing roller 125.

[0062] The specific configuration of the second driving force transmission unit is not limited to the configuration consisting of the combination of gears 104a, 104b, and 104c illustrated in Fig. 2. The specific configuration of the second driving force transmission unit may be any configuration using any mechanism as long as it is capable of transmitting the driving force generated by driving toner supply roller 134 to developing roller 125.

[0063] To drive the developing roller 125 and the toner supply roller 134 mentioned above The structure In this configuration, the above R must satisfy the relationship 1.2≦R≦1.3. To achieve this, the toner supply roller 134, the second driving force transmission unit, and the developing roller 125 must be drivingly connected. In other words, the radius of the developing roller 125 must be r D [mm], and the radius of the toner supply roller 134 is r RS [mm] and do Here, the radius r of the developing roller 125 D and the radius r of the toner supply roller 134 RS In contrast to under In the formula (E2), λ represents the ratio of rotational angular velocities. λ=ω RS / ω D (E2) (In formula (E2), ω RS represents the rotational angular velocity [rad / s] of the toner supply roller 134, and ω D represents the rotational angular velocity [rad / s] of the developing roller 125.

[0064] FIG. 3 shows another example of a configuration for driving the developing roller and the toner supply roller. The driving force input to coupling 201 is transmitted to gear 204a through intermediate member 202, and then to gears 204b and 204c in this order, thereby rotating and driving developing roller 225. The rotational driving force is then transmitted to gears 204d, 204e, and 204f in this order, thereby rotating and driving toner supply roller 234. In the present invention, from the viewpoint of suppressing an increase in the coefficient of dynamic friction between the developing roller and the photosensitive member due to changes in the surface of the developing roller, the above R satisfies 1.2≦R≦1.3. vinegar. The process cartridge according to the present invention can be used in laser beam printers, LED printers, copiers, facsimiles, and multifunction machines thereof. [Example]

[0065] 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 examples, "parts" are by mass unless otherwise specified. Moreover, Examples 2 and 4 to 26 in the following description are reference examples.

[0066] <Production of electrophotographic photoreceptors> <Preparation of Photoreceptor 1> (Support) A machined aluminum alloy cylinder having an outer diameter of 24 mm, a length of 257 mm and a wall thickness of 0.75 mm was used as the support.

[0067] (Formation of undercoat layer) One hundred parts of rutile-type titanium dioxide particles (product name: MT-600B, average primary particle size: 50 nm, manufactured by Teika) were mixed with 500 parts of toluene and stirred, and 5.0 parts of vinyltrimethoxysilane (product name: KBM-1003, manufactured by Shin-Etsu Chemical) were added and stirred for 8 hours. The toluene was then removed by distillation under reduced pressure, and the mixture was dried at 120°C for 3 hours to obtain rutile-type titanium dioxide particles that had been surface-treated with vinyltrimethoxysilane. Next, the following materials were prepared: 18 parts of rutile titanium dioxide particles surface-treated with vinyltrimethoxysilane N-methoxymethylated nylon (product name: Torezin EF-30T, manufactured by Nagase ChemteX): 4.5 parts Copolymer nylon resin (product name: Amilan (trademark) CM8000, manufactured by Toray Industries): 1.5 parts These were added to a mixed solvent of 90 parts of methanol and 60 parts of 1-butanol to prepare a dispersion, which was then dispersed in a vertical sand mill using glass beads with a diameter of 1.0 mm for 5 hours to prepare a coating solution for the undercoat layer. The support was dip-coated with this undercoat layer coating solution to form a coating film, and the coating film was dried at 100° C. for 10 minutes to form an undercoat layer with a thickness of 2.00 μm.

[0068] (Formation of Charge Generation Layer) As a charge-generating substance, 10 parts of Y-type oxytitanium phthalocyanine crystals, which have a strong peak at a Bragg angle (2θ±0.2°) of 27.3° in CuKα characteristic X-ray diffraction, were prepared. 10 parts of this Y-type oxytitanium phthalocyanine crystals and 150 parts of 4-methoxy-4-methylpentanone-2 were placed in a sand mill using glass beads with a diameter of 1 mm, and were ground and dispersed for 1.5 hours using the sand grinding mill. Next, 105 parts of a solution in which 5 parts of polyacetal resin (trade name: S-LEC BX-1, manufactured by Sekisui Chemical Co., Ltd.) had been dissolved in 100 parts of 4-methoxy-4-methylpentanone-2 was added, and the mixture was dispersed for 0.5 hours. Then, 250 parts of 1,2-dimethoxyethane was added to prepare a coating solution for the charge generation layer. The coating solution for the charge generation layer was dip-coated onto the resulting undercoat layer to form a coating film, which was then dried at 100°C for 10 minutes to form a charge generation layer with a thickness of 0.15 μm.

[0069] The X-ray diffraction measurements were carried out under the following conditions. [Powder X-ray diffraction measurement] Measuring equipment used: Rigaku Electric Co., Ltd., X-ray diffraction equipment RINT-TTRII X-ray tube:Cu Tube voltage: 50KV Tube current: 300mA Scanning method: 2θ / θ scan Scan speed: 4.0° / min Sampling interval: 0.02° Starting angle (2θ): 5.0° Stop angle (2θ): 40.0° Attachment: Standard sample holder Filter: Not used Incident Monochromator: Used Counter monochromator: Not used Divergence slit: open Divergence vertical limit slit: 10.00 mm Scattering slit: open Receiving slit: open Flat plate monochromator: used Counter: Scintillation counter

[0070] (Formation of surface layer (charge transport layer)) Next, the following materials were prepared: 56 parts of a charge transport material represented by the following formula (CTM1): 26 parts of a charge transport material represented by the following formula (CTM2): 5 parts of a charge transport material represented by the following formula (CTM3): 30 parts of a polyarylate resin having a molar ratio of structural units represented by the following formula (A1-1) to structural units represented by the following formula (A2-1) of 1.2:0.9: 70 parts of a polycarbonate resin having a structural unit represented by the following formula (A3): These were dissolved in a mixed solvent of 23 parts orthoxylene, 23 parts methyl benzoate, and 23 parts dimethoxymethane to prepare a surface layer coating solution. The charge generating layer was dip-coated with this surface layer coating solution to form a coating film, and the coating film was dried at 125°C for 30 minutes to form a surface layer with a thickness of 15 μm. [ka] [ka] [ka] [ka] [ka] [ka]

[0071] (Analysis of the surface layer of an electrophotographic photoreceptor) The polymer component recovered from the surface layer of the obtained photoreceptor was dissolved in deuterated chloroform. 1 H-nuclear magnetic resonance analysis revealed that 1H-NMR spectra were obtained. 1 The H-NMR spectrum had peaks at 8.97±0.02, 8.43±0.02, 7.67±0.02, 8.30±0.02, 1.71±0.03, 0.42±0.02, and 1.01±0.02 ppm, which identified that the surface layer of the photoreceptor contained structural units represented by formula (A1) and (A2). Also 1 The integrals at 1.71±0.03 ppm, 1.01±0.02 ppm, and 8.30±0.02 ppm were calculated from the H-NMR spectrum and divided by the number of protons. The integral per proton (hereinafter referred to as 1H) at 8.30±0.02 ppm was set to 1, and the ratio of the integral per 1H at 1.71±0.03 ppm to the integral per 1H at 1.01±0.02 ppm was calculated. This ratio was used as the molar ratio of the structural unit represented by formula (A1) to the structural unit represented by formula (A2) in the surface layer. The molar ratio of the structural unit represented by formula (A1) to the structural unit represented by formula (A2) in the surface layer of photoreceptor 1 was 1.2:0.9 (structural unit represented by formula (A1) : structural unit represented by formula (A2)). 1 From the H-NMR spectrum, an integral value of 2.25±0.02 (pk1) ppm was calculated, indicating a polycarbonate resin having a structural unit represented by formula (A3). Furthermore, integral values ​​of 1.71±0.03 (pk2), 1.01±0.02 (pk3), 8.30±0.02, 8.43±0.02 (pk4), and 8.97±0.02 (pk5) ppm were calculated. These calculated values ​​were divided by the number of protons to calculate the integral value per H. The integral value per H for each of pk1 to pk5 was multiplied by the molecular weight, and the proportion of pk2 to pk5, with the sum of pk1 to pk5 taken as 100%, was used to determine the polyarylate resin content (mass %) relative to the total mass of the surface layer. The polyarylate resin content of the surface layer of photoreceptor 1 relative to the total mass of the surface layer was 20% by mass.

[0072] <Preparation of photoreceptors 2 to 15> Photoreceptors 2 to 15 were produced in the same manner as photoreceptor 1, except that the types and mixing ratios of materials were appropriately adjusted to obtain surface layers with the configurations shown in Table 1.

[0073] <Preparation of Photoreceptor 16> The surface layer of photoreceptor 1 was formed in the same manner as photoreceptor 1, except that the polycarbonate resin having the structural unit represented by formula (A3) was changed to a polycarbonate resin having the structural unit represented by the following formula (A4). [ka]

[0074] [Table 1]

[0075] In addition, (A1-2) and (A2-2) in Table 1 are structural units represented by the following formula (A1-2) and (A2-2), respectively. [ka]

[0076] [ka]

[0077] <Preparation of Photoreceptor 17> Photoreceptor 17 was produced in the same manner as in the formation of the surface layer of photoreceptor 1, except that the surface layer coating liquid was prepared as follows. The following materials were prepared: 56 parts of a charge transport material represented by formula (CTM1) 26 parts of a charge transport material represented by formula (CTM2) 5 parts of a charge transport material represented by formula (CTM3), 100 parts of a polyarylate resin having a structural unit represented by formula (A5) These were dissolved in a mixed solvent of 23 parts of orthoxylene / 23 parts of methyl benzoate / 23 parts of dimethoxymethane to prepare a coating solution for the charge transport layer. [ka]

[0078] <Preparation of developing roller 1> (Preparing the base) A stainless steel (SUS304) mandrel with an outer diameter of 6 mm and a length of 270 mm was prepared, and a conductive vulcanizing adhesive (product name: Metalock U-20, manufactured by Toyo Kagaku Kenkyusho) was applied to the circumferential surface of the mandrel and baked to prepare the mandrel as the base.

[0079] (Formation of the first elastic layer) The materials for the elastic layer shown in Table 2 were mixed for 16 minutes using a 6-liter pressure kneader (trade name: TD6-15MDX, manufactured by Toshin Co., Ltd.) at a filling rate of 70% by volume and a blade rotation speed of 30 rpm to obtain mixture A.

[0080] [Table 2]

[0081] Next, the materials shown in Table 3 were mixed with open rolls having a roll diameter of 12 inches (0.30 m) at a front roll rotation speed of 10 rpm, a rear roll rotation speed of 8 rpm, and a roll gap of 2 mm, with a total of 20 left and right reversals. After that, the roll gap was set to 0.5 mm and thin-threading was performed 10 times to obtain mixture B.

[0082] [Table 3]

[0083] Next, the mixture B was extruded simultaneously with the mandrel by extrusion molding using a crosshead to form a cylindrical shape coaxially with the mandrel as the center, and a layer of mixture B was formed on the outer peripheral surface of the mandrel. An extruder with a cylinder diameter of 45 mm (Φ45) and L / D=20 was used, and the temperatures during extrusion were controlled to a head of 90°C, a cylinder of 90°C, and a screw of 90°C. Both longitudinal ends of the mandrel of the layer of mixture B were cut, and the length of the layer of mixture B in the longitudinal direction of the mandrel was set to 237 mm. Thereafter, the mandrel was heated in an electric furnace at a temperature of 160°C for 40 minutes to vulcanize the layer of mixture B, thereby forming a vulcanized member. Subsequently, the surface of the vulcanized member was polished with a plunge-cut grinding type polishing machine to obtain a roller in which a first elastic layer having a thickness of 3.0 mm was formed on the outer periphery of the core metal.

[0084] (Formation of second elastic layer) The materials listed in Table 4, except for the roughness-forming particles, were mixed and stirred to form the second elastic layer. The materials were then dissolved in methyl ethyl ketone (Kishida Chemical Co., Ltd.) to a solids concentration of 30% by mass, mixed, and uniformly dispersed using a sand mill. Methyl ethyl ketone was added to this mixture to adjust the solids concentration to 25% by mass, and the materials listed in the roughness-forming particles column in Table 4 were added. The mixture was then stirred and dispersed using a ball mill to obtain a coating solution for the second elastic layer. The roller on which the first elastic layer had been formed was immersed in the coating solution to coat the second elastic layer to a thickness of approximately 15 μm. The coating was then dried and cured by heating at 135°C for 60 minutes, forming a second elastic layer. This resulted in the development roller 1.

[0085] [Table 4]

[0086] (Analysis of developing roller 1) The developing roller was left for 24 hours in an environment with a temperature of 23°C and a relative humidity of 53%. Next, a micro rubber hardness tester (product name: MD-1capa, manufactured by Kobunshi Keiki Co., Ltd.) was used with a 0.16 mm diameter indenter to measure the hardness at 12 points at 90° intervals around the circumference of the developing roller, at positions 20 mm inward from the center and both ends, and the average of these measurements was taken as the MD-1 hardness. The MD-1 hardness of developing roller 1 was 50°.

[0087] <Production of developing roller 2> In forming the first elastic layer, the amount of carbon black used in preparing mixture A was changed to 30 parts by mass, and the other factors were the same as in the case of developing roller 1. The MD-1 hardness of the surface of the resulting developing roller 2 is shown in Table 6.

[0088] <Production of developing roller 3> In forming the first elastic layer, the amount of zinc oxide used in preparing mixture A was changed to 14 parts by mass, and the other factors were the same as in the case of developing roller 1. The MD-1 hardness of the surface of the resulting developing roller 3 is shown in Table 6.

[0089] <Production of Developing Roller 4> Developing roller 4 was produced in the same manner as developing roller 1, except that the method for forming the first elastic layer was changed as follows. The MD-1 hardness of the surface of the resulting developing roller 4 is shown in Table 6. (Formation of the first elastic layer) For the material of the first elastic layer, the materials shown in Table 5 were mixed in a kneader (product name: Trimix TX-15, manufactured by Inoue Seisakusho Co., Ltd.) to form an addition-type silicone rubber composition, which was then poured into a mold heated to 115° C. After the material was poured, the mixture was heated and molded at 120° C. for 10 minutes, cooled to room temperature, and then demolded from the mold to obtain a roller having a first elastic layer with a thickness of 3.0 mm formed on the outer periphery of a core metal.

[0090] [Table 5]

[0091] <Production of the developing roller 5> Among the materials for the first elastic layer, dimethylpolysiloxane was changed to HMS-082 (manufactured by Gelest Co., Ltd.), and the amount of HMS-082 used was changed to 3 parts by mass, and the developing roller was produced in the same manner as the developing roller 4. The MD-1 hardness of the surface of the resulting developing roller 5 is shown in Table 6.

[0092] <Production of the developing roller 6> Among the materials for the first elastic layer, dimethylpolysiloxane was changed to HMS-082 (manufactured by Gelest Co., Ltd.), and the amount of HMS-082 used was changed to 6 parts by mass, except that the developing roller was produced in the same manner as the developing roller 4. The MD-1 hardness of the surface of the resulting developing roller 6 is shown in Table 6.

[0093] [Table 6]

[0094] <Production of Toner Supply Roller 1> A 5 mm diameter core made of stainless steel (SUS304) was coated with a primer (product name: DY39-012, manufactured by Dow Corning Toray Co., Ltd.) and baked to prepare the shaft. The following materials (A) to (F) were blended, and the resulting blend was mixed to obtain a urethane rubber composition, which was then foamed by a mechanical froth method to produce a polyurethane foam. This polyurethane foam was cut into a rectangular parallelepiped shape measuring 19 mm square and 220 mm long, and a shaft insertion hole of 5 mm diameter was provided in the center of each 19 mm square face along the longitudinal direction. The shaft was press-fitted into the shaft insertion hole, and the shaft and polyurethane foam were bonded together by heat welding. Thereafter, the outer periphery of the polyurethane foam was polished using a traverse type processing machine to prepare a conductive roll with an outer diameter of 13 mm. (A): Carbon black (Ketjen Black 600JD): 5.0 parts by mass (B): Polyol A (polyethylene propylene ether triol having a number average molecular weight of 2000, trade name: Actocol EP-550N, manufactured by Mitsui Chemicals, Inc.): 100.0 parts by mass (C): Polyisocyanate mixture (NCO% = 45, MDI = 20%, product name: Cosmonate TM20, manufactured by Mitsui Chemicals, Inc.): 24.4 parts by mass (D): Silicone foam stabilizer (product name: SRX274C, manufactured by Toray Dow Corning Silicones Co., Ltd.): 1.0 part by mass (E): 0.3 parts by mass of tertiary amine catalyst A (a mixture of bis(2-dimethylaminoethyl) ether and dipropylene glycol, trade name: TOYOCAT-ET, manufactured by Tosoh Corporation) (F): Amine catalyst B (trade name: TOYOCAT-L33, manufactured by Tosoh Corporation): 0.2 parts by mass

[0095] <Production of Toner Supply Roller 2> A 5 mm diameter core made of stainless steel (SUS304) was coated with a primer (product name: DY39-012, manufactured by Dow Corning Toray Co., Ltd.) and baked to prepare the shaft. The following materials (A) to (D) were blended and thoroughly kneaded with a twin roll mill to obtain a rubber composition. (A): Millable type silicone rubber (KE-3601SB-U, manufactured by Shin-Etsu Chemical Co., Ltd.): 100 parts by mass (B): White catalyst (C-25A, manufactured by Shin-Etsu Chemical Co., Ltd.): 1.0 part by mass (C): Crosslinking agent (C-25B, manufactured by Shin-Etsu Chemical Co., Ltd.): 2.5 parts by mass (D): Chemical foaming agent (AIBN, manufactured by Otsuka Chemical Co., Ltd.): 10 parts by mass The shaft and rubber composition were extruded as a single unit using an extruder, and the rubber composition was heated in an infrared heating oven at 230°C for 20 minutes for primary vulcanization, followed by secondary vulcanization in a hot air drying oven at 230°C for 7 hours to produce a roller base with a foam layer. The outer periphery of this roller base was polished using a traverse processing machine to produce a conductive roll with an outer diameter of 13 mm.

[0096] <Production of Toner Supply Roller 3> It was produced in the same manner as toner supply roller 1, except that the conductive filler was changed from carbon black to an ionic conductive material (lithium N,N-bis(trifluoromethanesulfonyl)imide (product name: EF-N115, manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.); 5 parts by mass).

[0097] [evaluation] <Evaluation of the variation in the dynamic friction coefficient (Evaluation (1))> A surface property measuring instrument (product name: Heidon: Type 14, manufactured by Shinto Scientific Co., Ltd.) was used to measure the dynamic friction coefficient between the developing roller and the electrophotographic photosensitive member, and the fluctuation in the dynamic friction coefficient was evaluated. The jig of the measuring instrument was modified so that the developing roller could be brought into contact with the electrophotographic photosensitive member, and a vertical load of 60 g was applied using a weight. The electrophotographic photosensitive member was rotated at a speed of 310 rpm using a rotational support mechanism prepared separately from the measuring instrument, and the dynamic friction coefficient was measured. The coefficient of dynamic friction measured with a developing roller at room temperature is defined as A, and the coefficient of dynamic friction measured with a developing roller heated to a surface temperature of 40°C, assuming a temperature rise, is defined as B. The change in the coefficient of dynamic friction with and without a temperature rise was calculated as B / A x 100.

[0098] <Evaluation of the occurrence of banding images after repeated use in a room temperature environment (Evaluation (2))> In an environment with a temperature of 23°C and a relative humidity of 50%, the charging potential was set to -550V, the exposure potential to -100V, and 10,000 sheets of halftone images were continuously printed, depicting horizontal lines with a width of 1 dot and an interval of 2 dots in the direction perpendicular to the rotational direction of the photoreceptor. The electrophotographic device used here was a modified Hewlett-Packard laser beam printer. Specific examples include modified models such as Color Laser Jet Enterprise M653dn, Color Laser Jet Enterprise M553dn, and Color Laser Jet CP4525dn. The halftone images were visually inspected for streaky irregularities and evaluated according to the following criteria. (Evaluation criteria) A: No horizontal streaks are observed. B: Slight horizontal streak-like unevenness is observed. C: Horizontal streak-like irregularities are observed at positions corresponding to the rotation pitch of the charging roller. D: Significant horizontal streak-like unevenness is observed.

[0099] <Evaluation of the occurrence of banding images after repeated use in a low-temperature, low-humidity environment (Evaluation (3))> As in evaluation (2), a durability test was conducted in which 10,000 sheets were passed through in a low-temperature, low-humidity environment (temperature 15°C, relative humidity 10%). After passing 10,000 sheets, the image was evaluated in the same manner as in evaluation (2) above and judged according to the above criteria.

[0100] [Example 1] The electrophotographic photosensitive member 1 and developing roller 1 manufactured above were mounted on a modified Heidon: Type 14, and evaluation (1) was carried out. In the process cartridge, a counter configuration is used, and a coupling, intermediate body, and gear are arranged as shown in Figure 2, so that a driving force is input to the end of the toner supply roller shaft (hereinafter referred to as "RS input configuration"). In addition, the arrangement of the coupling, intermediate body, and gear, the gear ratio of each gear, and the radius r of the developing roller are set so that R = 1.25. D and the radius r of the toner supply roller RS The rotational angular velocity ω of the developing roller used was adjusted. D and the rotational angular velocity ω of the toner supply roller RS However, various gear ratios were configured so that λ shown in the following formula (E2) was λ=1.12. λ=ω RS / ω D (E2) In addition, the radius r of the developing roller used in this case D is r D = 12.00 [mm], and the radius r of the toner supply roller RS is r RS = 13.35 [mm]. Using these values, λ × r RS / r D = 1.25, and 1.2 ≤ λ × r RS / r D Meets the condition of ≦1.5. The electrophotographic photosensitive member 1, developing roller 1, and toner supply roller 1 manufactured above were attached to this process cartridge, and evaluations (2) and (3) were carried out. The results are shown in Table 7.

[0101] [Examples 2 to 13, 15 to 26] Evaluation was carried out in the same manner as in Example 1, except that the electrophotographic photosensitive member, developing roller, toner supply roller and R value were changed as shown in Table 7. The evaluation results are shown in Table 7.

[0102] [Example 14] As shown in Figure 3, a coupling, an intermediate body, and a gear were arranged so that an external driving force was input to the end of the mandrel of the developing roller (hereinafter referred to as "D input configuration"). Except for this, evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 7.

[0103] [Comparative Examples 1 to 3] Evaluation was carried out in the same manner as in Example 1, except that the combinations of the electrophotographic photosensitive member, developing roller, toner supply roller, and R value were changed as shown in Table 8. The evaluation results are shown in Table 8. In all of the comparative examples, the dynamic friction coefficient changed with temperature rise, and streaky defective images were noticeable.

[0104] [Table 7]

[0105] [Table 8]

[0106] The disclosure according to an embodiment of the present invention includes the following configuration. (Configuration 1) A process cartridge that is detachably mountable to a main body of an electrophotographic apparatus, The process cartridge is electrophotographic photoreceptors, a developing roller for developing an electrostatic latent image formed on the surface of the electrophotographic photosensitive member; and a toner supply roller that is disposed in contact with the developing roller and supplies toner to the developing roller; and The developing roller and the toner supply roller are The direction of movement of the surface of the developing roller and the direction of movement of the surface of the toner supply roller during operation are opposite to each other at the contact position between the developing roller and the toner supply roller, and The rotation occurs when R in the following formula (E1) satisfies 1.2≦R≦1.5. It is structured as follows: R=V RS / V D (E1) (In formula (E1), V RS represents the absolute value of the peripheral speed [m / s] of the toner supply roller, and V D represents the absolute value of the peripheral speed [m / s] of the developing roller.) the surface of the developing roller is the surface of an elastic layer, the toner supply roller has a shaft and a resin layer provided on an outer peripheral surface of the shaft, The electrophotographic photoreceptor has a surface layer containing a polyarylate resin having a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2): A process cartridge characterized by: [ka] [ka] (Configuration 2) The polymer component recovered from the surface layer of the electrophotographic photosensitive member is dissolved in deuterated chloroform. 1 Obtained by H-nuclear magnetic resonance analysis 1 2. The process cartridge according to claim 1, wherein the H-nuclear magnetic resonance spectrum has peaks at 8.97±0.02, 8.43±0.02, 7.67±0.02, 8.30±0.02, 1.71±0.03, 0.42±0.02, and 1.01±0.02 ppm. (Configuration 3) 3. The process cartridge according to Structure 1 or 2, wherein the molar ratio of the structural unit represented by Formula (A1) to the structural unit represented by Formula (A2) in the surface layer of the electrophotographic photosensitive member is within a range of 1.4:0.7 to 1.0:1.1 (structural unit represented by Formula (A1):structural unit represented by Formula (A2)). (Configuration 4) The process cartridge according to any one of Configurations 1 to 3, wherein the content of the polyarylate resin having the structural unit represented by Formula (A1) and the structural unit represented by Formula (A2) in the surface layer of the electrophotographic photosensitive member is 15 mass % or more relative to the total mass of the surface layer. (Configuration 5) a driving force receiving portion that receives a driving force for driving the toner supply roller; a first driving force transmitting portion for transmitting the driving force received by the driving force receiving portion to the toner supply roller; a second driving force transmission unit for transmitting a driving force generated by driving the toner supply roller to the developing roller; 5. The process cartridge according to any one of Configurations 1 to 4, comprising: (Configuration 6) the second driving force transmission unit includes a third driving force transmission unit, a fourth driving force transmission unit, and a fifth driving force transmission unit, the third driving force transmission unit is provided at an end of the shaft of the toner supply roller and transmits a driving force generated by driving the toner supply roller to the fourth driving force transmission unit; the fourth driving force transmission unit is driven by the driving force received from the third driving force transmission unit to transmit the driving force to the fifth driving force transmission unit, the fifth driving force transmission unit is provided at an end of a shaft body of the developing roller, and receives a driving force from the fourth driving force transmission unit to drive the developing roller. 6. The process cartridge according to claim 5. (Configuration 7) The radius of the developing roller is r D [mm], and the radius of the toner supply roller is r RS[mm], the toner supply roller, the second driving force transmission unit, and the developing roller have a width λ, which is expressed by the following formula (E2), of 1.2≦λ×r RS / r D 7. The process cartridge according to aspect 5 or 6, wherein the drive coupling satisfies the relationship ≦1.5. λ=ω RS / ω D (E2) (In formula (E2), ω RS represents the rotational angular velocity [rad / s] of the toner supply roller, and ω D represents the rotational angular velocity [rad / s] of the developing roller. (Configuration 8) 8. The process cartridge according to any one of Configurations 1 to 7, wherein R satisfies 1.2≦R≦1.3. (Configuration 9) 9. The process cartridge according to any one of Configurations 1 to 8, wherein the MD-1 hardness of the surface of the developing roller is 20° or more and 55° or less. (Configuration 10) 10. The process cartridge according to any one of Configurations 1 to 9, wherein the resin layer is a foam layer. (Configuration 11) 11. The process cartridge according to any one of Configurations 1 to 10, wherein the resin layer contains a polyurethane resin as a binder resin. (Configuration 12) 12. The process cartridge according to any one of Configurations 1 to 11, wherein the resin layer contains an electronically conductive filler. (Configuration 13) 13. An electrophotographic apparatus comprising the process cartridge according to any one of Configurations 1 to 12. [Explanation of symbols]

[0107] 1 Photosensitive drum 2 Charging roller 4 Development unit 6 Cleaning material 7 Rubber Blade 8 Cleaning support member 25 Developing roller 26 Photoconductor unit 31 Developing frame 34 Toner supply roller 35 Developing blade 70 Process cartridge 101 Coupling (driving force receiving part) 102 Intermediates 103 Driving force transmission member 104a Gear (third driving force transmission part) 104b Gear (fourth driving force transmission part) 104c Gear (fifth driving force transmission part) 105 shaft 106 Core body 125 Developing roller 134 Toner supply roller 225 Developing roller 234 Toner supply roller

Claims

1. A process cartridge that is detachably mountable to a main body of an electrophotographic apparatus, The process cartridge is an electrophotographic photoreceptor; a developing roller for developing an electrostatic latent image formed on the surface of the electrophotographic photosensitive member; a toner supply roller that is disposed in contact with the developing roller and supplies toner to the developing roller; a driving force receiving portion that receives a driving force for driving the toner supply roller; a first driving force transmitting portion for transmitting the driving force received by the driving force receiving portion to the toner supply roller; a second driving force transmission unit for transmitting a driving force generated by driving the toner supply roller to the developing roller; and The developing roller and the toner supply roller are The direction of movement of the surface of the developing roller and the direction of movement of the surface of the toner supply roller during operation are opposite to each other at the contact position between the developing roller and the toner supply roller, and The rotation occurs when R represented by the following formula (E1) satisfies 1.2≦R≦1.

3. It is structured as follows: R=V ＲＳ / V Ｄ (E1) (In formula (E1), V ＲＳ represents the absolute value of the peripheral speed [m / s] of the toner supply roller, and V Ｄ represents the absolute value of the peripheral speed [m / s] of the developing roller.) the surface of the developing roller is the surface of an elastic layer, the MD-1 hardness of the surface of the developing roller is 50° or more and 55° or less; the toner supply roller has a shaft and a resin layer provided on an outer peripheral surface of the shaft, the electrophotographic photoreceptor has a surface layer containing a polyarylate resin, The polyarylate resin has a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2), the molar ratio of the structural unit represented by the following formula (A1) to the structural unit represented by the following formula (A2) in the surface layer of the electrophotographic photosensitive member is within a range of 1.4:0.7 to 1.2:0.9 (structural unit represented by formula (A1):structural unit represented by formula (A2)); A process cartridge characterized by: 【Chemistry 1】 【Chemistry 2】

2. The polymer component recovered from the surface layer of the electrophotographic photosensitive member is dissolved in deuterated chloroform. １ Obtained by subjecting to H-nuclear magnetic resonance analysis １ 2. The process cartridge according to claim 1, wherein the H-nuclear magnetic resonance spectrum has peaks at 8.97±0.02, 8.43±0.02, 7.67±0.02, 8.30±0.02, 1.71±0.03, 0.42±0.02, and 1.01±0.02 ppm.

3. 2. The process cartridge according to claim 1, wherein the content of the polyarylate resin having the structural unit represented by formula (A1) and the structural unit represented by formula (A2) in the surface layer of the electrophotographic photosensitive member is 15% by mass or more relative to the total mass of the surface layer.

4. the second driving force transmission unit includes a third driving force transmission unit, a fourth driving force transmission unit, and a fifth driving force transmission unit, the third driving force transmission unit is provided at an end of the shaft of the toner supply roller and transmits a driving force generated by driving the toner supply roller to the fourth driving force transmission unit; the fourth driving force transmission unit is driven by the driving force received from the third driving force transmission unit to transmit the driving force to the fifth driving force transmission unit, the fifth driving force transmission unit is provided at an end of a shaft body of the developing roller, and receives a driving force from the fourth driving force transmission unit to drive the developing roller. The process cartridge according to claim 1 .

5. 2. The process cartridge according to claim 1, wherein the resin layer is a foam layer.

6. 2. The process cartridge according to claim 1, wherein the resin layer contains a polyurethane resin as a binder resin.

7. 2. The process cartridge according to claim 1, wherein the resin layer contains an electronically conductive filler.

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

Images