JP2005234321A - Electrophotographic photoreceptor, process cartridge and electrophotographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress significant lowering of sensitivity and occurrence of a ghost and frictional memory as problems specific to an electrophotographic photoreceptor using a curable resin in a surface layer. <P>SOLUTION: In this electrophotographic photoreceptor having an intermediate layer and a photosensitive layer in this order on a support, a surface layer of the electrophotographic photoreceptor contains a curable resin and the intermediate layer contains a copolymerized polyamide resin having a specified repeating structural unit and titanium oxide particles whose average primary particle diameter is ≤100 nm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrophotographic photosensitive member, a process cartridge having an electrophotographic photosensitive member, and an electrophotographic apparatus.

  In recent years, electrophotographic photoreceptors using organic photoconductive materials have been developed and put to practical use because of their advantages such as high safety, excellent productivity, and low cost.

  With recent demands for higher image quality, higher speed, and higher durability of electrophotographic apparatuses, electrophotographic photoreceptors are required to have improved mechanical durability, particularly surface mechanical durability.

  Further, the electrophotographic photoreceptor is also required to improve the surface releasability. If the releasability of the surface of the electrophotographic photosensitive member is low, the amount of toner (transfer residual toner) remaining on the surface of the electrophotographic photosensitive member after transferring the toner image to the transfer material increases. When the amount of the transfer residual toner is large, the output image becomes a so-called bulging shape, and there arises a problem that the toner is fused to the surface of the electrophotographic photosensitive member and filming occurs.

  As a technique for satisfying the above requirements for an electrophotographic photosensitive member, for example, Japanese Patent Application Laid-Open No. 05-181299 (Patent Document 1) discloses a phenol resin, which is a curable resin, as a binder resin for the surface layer of an electrophotographic photosensitive member. The technique used as is disclosed. Japanese Patent Application Laid-Open No. 57-030846 discloses a technique for controlling resistance of a surface layer by adding metal oxide particles as conductive particles to the surface layer of an electrophotographic photoreceptor.

  However, it is difficult to say that the electrophotographic photosensitive member having such a surface layer sufficiently satisfies the above requirements. At present, an electrophotographic photosensitive member exhibiting electrophotographic characteristics with little potential change due to repeated use, that is, an electrophotographic photosensitive member capable of outputting a high-quality image even after repeated use has not been obtained.

  In particular, when a curable resin is used as the binder resin for the surface layer of the electrophotographic photosensitive member, if it is repeatedly used in a low-temperature and low-humidity environment, a significant decrease in sensitivity occurs or the first cycle exposure (image exposure) history. May appear as a density difference in an output image (particularly a halftone image) in the second cycle, or a so-called ghost may occur. Further, the surface of the electrophotographic photosensitive member is rubbed by the vibration of a member (such as a cleaning blade) in contact with the electrophotographic photosensitive member, and the memory (rubbing memory) appears as a streak in the output image. There is also.

  An electrophotographic photoreceptor is generally produced by forming a photosensitive layer containing a photoconductive substance (a charge generating substance or a charge transporting substance) on a support. Usually, the surface of a member (such as a blank tube) used for a support has defects such as dirt, foreign matter adhesion, and scratches. These defects have a more or less adverse effect on electrophotographic characteristics. An intermediate layer for covering these defects is often provided between them. In addition, in order to remove these defects, the surface of the member used for the support is cut or polished, and high-precision cleaning is also performed, which increases the cost of the electrophotographic photosensitive member. Leads to.

The intermediate layer is generally formed using an inorganic material such as aluminum oxide or aluminum hydroxide, or an organic material such as polyvinyl pyrrolidone, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide, or polyamide. Further, an intermediate layer obtained by adding inorganic particles, organic pigments, or the like to these organic materials is also known.
JP 05-181299 A Japanese Unexamined Patent Publication No. 57-030846

  An object of the present invention is to suppress significant sensitivity reduction, ghosting, and rubbing memory, which are problems specific to an electrophotographic photoreceptor using a curable resin for the surface layer.

  It is another object of the present invention to provide a process cartridge and an electrophotographic apparatus having an electrophotographic photosensitive member in which remarkable sensitivity reduction, generation of ghost and rubbing memory are suppressed.

The present invention provides an electrophotographic photosensitive member having an intermediate layer and a photosensitive layer in this order on a support,
The surface layer of the electrophotographic photoreceptor contains a curable resin,
The intermediate layer contains a copolymerized polyamide resin having a repeating structural unit represented by the following formula (1), and titanium oxide particles having an average primary particle size of 100 nm or less.

(In formula (1), R ¹⁰¹ and R ¹⁰² each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted aryl group. Ar ¹⁰¹ and Ar ¹⁰² each independently represent a substituted or unsubstituted cyclohexylene group or a substituted or unsubstituted cyclohexylidene group.

  The present invention also provides a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

  According to the present invention, it is possible to suppress the significant reduction in sensitivity, the occurrence of ghost and rubbing memory, which are problems specific to an electrophotographic photoreceptor using a curable resin for the surface layer.

  In addition, according to the present invention, it is possible to provide a process cartridge and an electrophotographic apparatus having an electrophotographic photosensitive member in which remarkable sensitivity reduction, generation of ghost and rubbing memory are suppressed.

  Hereinafter, the present invention will be described in detail.

  As described above, the electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor having an intermediate layer and a photosensitive layer in this order on a support.

  The photosensitive layer is separated into a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material even if it is a single layer type photosensitive layer containing the charge transporting material and the charge generating material in the same layer. A laminated type (functional separation type) photosensitive layer may be used, but a laminated type photosensitive layer is preferred from the viewpoint of electrophotographic characteristics. The laminated photosensitive layer has a normal layer type photosensitive layer laminated in the order of the charge generation layer and the charge transport layer from the support side, and a reverse layer type photosensitive layer laminated in the order of the charge transport layer and the charge generation layer from the support side. However, a normal photosensitive layer is preferred from the viewpoint of electrophotographic characteristics.

  FIG. 1 shows an example of the layer structure of the electrophotographic photosensitive member of the present invention.

  In the electrophotographic photosensitive member having the layer structure shown in FIG. 1A, an intermediate layer 103, a single-layer type photosensitive layer 104 containing a charge generating substance and a charge transporting substance are sequentially provided on a support 101. Further thereon, a layer 105 containing a curable resin is provided as a surface layer. In addition, the electrophotographic photosensitive member having the layer structure shown in FIG. 1B includes an intermediate layer 103, a charge generation layer 1041 containing a charge generation material, and a charge transport layer 1042 containing a charge transport material on a support 101. Are provided in order, and a layer 105 containing a curable resin is provided thereon as a surface layer.

  In addition, in the electrophotographic photosensitive member having the layer structure shown in FIG. 1C, an intermediate layer 103 and a charge generation layer 1041 containing a charge generation material are sequentially provided on a support 101, and a surface is formed on the intermediate layer 103. A layer 105 ′ containing a curable resin is provided as a layer. The layer 105 ′ containing a curable resin also has a function (charge transporting ability) similar to that of the charge transport layer 1042 by containing a charge transporting substance.

  Further, the layer 105 containing the curable resin of the electrophotographic photosensitive member having the layer structure shown in FIGS. 1A and 1B may also contain a charge transport material. When the layer 105 containing a curable resin contains a charge transport material, the layer 105 is also a second photosensitive layer (second charge transport layer).

  Any other layer configuration may be used as long as the surface layer of the electrophotographic photosensitive member contains a curable resin, but the preferred layer configuration in the present invention is the layer configuration shown in FIG. It is. Hereinafter, the electrophotographic photosensitive member having the layer structure shown in FIG. 1B will be described as an example.

  As a support body, what is necessary is just to have electroconductivity (electroconductive support body), For example, metal (alloy-made) support bodies, such as aluminum, aluminum alloy, and stainless steel, can be used. Moreover, the said metal support body and plastic support body which have the layer in which aluminum, aluminum alloy, stainless steel, nickel, copper, iron, an indium oxide tin oxide alloy etc. were formed into a film by vacuum deposition can also be used. In addition, a support in which conductive particles such as carbon black, tin oxide particles, titanium oxide particles, and silver particles are impregnated into plastic or paper together with an appropriate binder resin, or a plastic support having a conductive binder resin, etc. Can also be used. In addition, examples of the shape of the support include a cylindrical shape and a belt shape, and a cylindrical shape is preferable.

  The intermediate layer of the electrophotographic photoreceptor of the present invention contains a copolymerized polyamide resin having a repeating structural unit represented by the above formula (1).

As described above, R ¹⁰¹ and R ¹⁰² in the formula (1) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted aryl group. Among these, a hydrogen atom, an alkyl group, and an alkoxy group are preferable. Examples of the alkyl group of R ¹⁰¹ and R ^{102 in} the above formula (1) include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group, and the alkoxy group includes a methoxy group, an ethoxy group, and an n-propoxy group. Group, isopropoxy group and the like, and aryl group includes phenyl group, naphthyl group, anthryl group, pyrenyl group and the like.

In addition, ^examples of the substituent that the alkyl group, alkoxy group, and aryl group of R ¹⁰¹ and R ¹⁰² may have include a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, a methyl group, and an ethyl group. Alkyl groups such as propyl group, butyl group, alkoxy groups such as methoxy group, ethoxy group, propoxy group, butoxy group, aryl groups such as phenyl group, naphthyl group, anthryl group, pyrenyl group, pyridyl group, thienyl And monovalent heterocyclic groups such as a group, a furyl group, and a quinolyl group.

  The copolymerized polyamide resin used for the intermediate layer of the electrophotographic photoreceptor of the present invention is one or more repeating structural units other than the repeating structural unit represented by the above formula (1) and the repeating structural unit represented by the above formula (1). And a copolymer. This copolymer may be a binary copolymer or a ternary or higher copolymer.

  As the repeating structural unit other than the repeating structural unit represented by the above formula (1), a repeating structural unit having an imino group (—NH—) at the end in the same manner as the repeating structural unit represented by the above formula (1), Examples thereof include a repeating structural unit represented by the above formula (1) and a repeating structural unit having a carbonyl group (—CO—) for forming an amide bond at the end. Examples of such repeating structural units include repeating structural units derived from lactams such as γ-butyrolactam, ε-caprolactam, lauryl lactam, 1,4-butanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1, Repetitive structural units derived from dicarboxylic acids such as 20-eicosanedicarboxylic acid and diamines such as 1,4-butanediamine, 1,6-hexamethylenediamine, 1,8-octamethylenediamine, 1,12-dodecanediamine And repeating structural units derived from piperazine. However, since the copolymerized polyamide resin used for the intermediate layer of the electrophotographic photosensitive member of the present invention is a kind of polyamide resin, at least one of the repeating structural units other than the repeating structural unit represented by the above formula (1). The seed is a repeating structural unit having a carbonyl group at the end.

  The copolymerization ratio of the copolymerized polyamide resin used for the intermediate layer of the electrophotographic photoreceptor of the present invention is such that the repeating structural unit represented by the above formula (1) is all of the repeating structural units of the copolymerized polyamide resin. The amount is preferably 5 to 40 mol%, more preferably 5 to 30 mol%, based on the number of moles. If the ratio of the repeating structural unit represented by the above formula (1) in the copolymerized polyamide resin is too low, the effect of the present invention is difficult to obtain. If it is too high, the intermediate layer becomes a hard and brittle film. When a photosensitive layer is formed on the layer, cracks or the like may occur.

  The number average molecular weight of the copolymerized polyamide resin used in the intermediate layer of the electrophotographic photosensitive member of the present invention is preferably 10,000 to 50,000, and more preferably 15,000 to 35,000. If the number average molecular weight is too small or too large, it is difficult to maintain the film uniformity of the intermediate layer.

  As a method for producing a copolymerized polyamide used for the intermediate layer of the electrophotographic photosensitive member of the present invention, a usual method for producing a polyamide resin (such as a polycondensation method) can be applied. Examples thereof include a combination method and an interfacial polymerization method. In the polymerization, a monobasic acid such as acetic acid or benzoic acid, or a monoacid base such as hexylamine or aniline may be added as a molecular weight regulator. In addition, heat stabilizers such as sodium phosphite, sodium hypophosphite, phosphorous acid, hypophosphorous acid, hindered phenol, and other polymerization additives may be added.

  Specific examples of the repeating structural unit represented by the above formula (1) are shown below.

  Specific examples of the repeating structural unit other than the repeating structural unit represented by the above formula (1) are shown below.

  Specific examples of the copolymerized polyamide resin used for the intermediate layer of the electrophotographic photoreceptor of the present invention are shown below.

  In the intermediate layer of the electrophotographic photosensitive member of the present invention, a resin other than the copolymerized polyamide resin may be used in combination. Examples of the resin other than the copolymerized polyamide resin include acrylic resin, allyl resin, alkyd resin, ethyl cellulose resin, ethylene-acrylic acid copolymer, epoxy resin, casein resin, silicone resin, gelatin resin, nylon, phenol resin, and butyral resin. Polyacrylate resins, polyacetal resins, polyamide resins other than the above-mentioned copolymerized polyamide resins, polyallyl ether resins, polyimide resins, polyurethane resins, polyester resins, polyethylene resins, polycarbonate resins, polystyrene resins, polysulfone resins, polyvinyl alcohol resins, polybutadiene resins , Polypropylene resin, urea resin and the like. When using the said copolymerization polyamide resin and other resin together in an intermediate | middle layer, it is preferable that the ratio of the said copolymerization polyamide resin is 50-99 mass% with respect to the resin total mass used for an intermediate | middle layer.

  The intermediate layer of the electrophotographic photoreceptor of the present invention also contains titanium oxide particles having an average primary particle size of 100 nm or less.

  Examples of the crystalline form of the titanium oxide particles used in the intermediate layer of the electrophotographic photoreceptor of the present invention include amorphous, anatase, rutile, brookite and the like, and any crystalline form of titanium oxide particles can be used.

  Further, in order to improve the dispersibility of the titanium oxide particles in the intermediate layer, to adjust the electrical resistance, and to improve the humidity dependency, the titanium oxide used in the intermediate layer of the electrophotographic photosensitive member of the present invention. Various surface treatments may be performed on the particles.

  With respect to the particle size of the titanium oxide particles used in the intermediate layer of the electrophotographic photoreceptor of the present invention, the average primary particle size must be 100 nm or less, preferably 60 nm or less, from the viewpoint of electrical characteristics and liquid stability. is there. The lower limit of the average primary particle size is preferably 10 nm or more.

  In the present invention, the particle size is a particle size determined by a TEM (transmission electron microscope).

  The ratio of the copolymerized polyamide and titanium oxide particles in the intermediate layer is preferably in the range of 1: 0.5 to 1: 4 (mass ratio) from the viewpoint of electrical characteristics and liquid stability.

  Moreover, you may add various additives to the intermediate | middle layer of the electrophotographic photoreceptor of this invention as needed. Examples of the additive include particles of metal oxides such as aluminum oxide, silicon oxide, calcium titanate, strontium titanate, tin oxide, and zinc oxide, carbon black, organic silicate compounds, and organic zirconium compounds. It is done. The ratio of the titanium oxide particles to these additives is preferably in the range of 1: 0 to 1: 0.5 (mass ratio).

  The intermediate layer can be formed by applying and drying an intermediate layer coating solution obtained by dispersing the titanium oxide particles together with the polyamide resin and a solvent. In order to improve the coating property of the intermediate layer coating solution, silicone oil, fluorine atom-containing surfactant, or the like may be added to the intermediate layer coating solution.

  The thickness of the intermediate layer is preferably 0.05 to 10 μm, and more preferably 0.2 to 5 μm. If the thickness of the intermediate layer is too thin, it is difficult to obtain the effect of the present invention, and if it is too thick, the residual potential tends to increase.

  Note that a conductive layer may be provided between the support and the intermediate layer for the purpose of preventing interference fringes due to scattering of laser light or the like. The conductive layer can be formed by dispersing conductive particles such as carbon black, metal particles, and metal oxide particles in a binder resin. The thickness of the conductive layer is preferably 1 to 40 μm, and more preferably 2 to 20 μm.

  The charge generation layer can be formed by applying and drying a charge generation layer coating solution obtained by dispersing a charge generation material together with a binder resin and a solvent. Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, a vibration mill, an attritor, a liquid collision type high-speed disperser, and the like. The ratio between the charge generating material and the binder resin is preferably in the range of 1: 0.5 to 1: 4 (mass ratio).

  Examples of the charge generating material include azo pigments such as monoazo, disazo, and trisazo, phthalocyanine pigments such as metal phthalocyanine and nonmetal phthalocyanine, indigo pigments such as indigo and thioindigo, and perylene acid anhydride and perylene imide. Perylene pigments, polycyclic quinone pigments such as anthraquinone and pyrenequinone, squarylium dyes, pyrylium salts and thiapyrylium salts, triphenylmethane dyes, inorganic substances such as selenium, selenium-tellurium, amorphous silicon, quinacridone pigments, And azurenium salt pigments, cyanine dyes, xanthene dyes, quinone imine dyes, styryl dyes, cadmium sulfide, and zinc oxide. These charge generation materials may be used alone or in combination of two or more.

  Examples of the binder resin used for the charge generation layer include acrylic resin, allyl resin, alkyd resin, epoxy resin, diallyl phthalate resin, silicone resin, styrene-butadiene copolymer, nylon, phenol resin, butyral resin, benzal resin, polyacrylate. Resin, Polyacetal resin, Polyamideimide resin, Polyamide resin, Polyallyl ether resin, Polyarylate resin, Polyimide resin, Polyurethane resin, Polyester resin, Polyethylene resin, Polycarbonate resin, Polystyrene resin, Polysulfone resin, Polyvinyl acetal resin, Polybutadiene resin, Polypropylene Resins, methacrylic resins, urea resins, vinyl chloride-vinyl acetate copolymers, vinyl acetate resins and the like. In particular, a butyral resin is preferable. These can be used singly or in combination of two or more as a mixture or copolymer.

  The solvent used in the coating solution for the charge generation layer is selected from the solubility and dispersion stability of the binder resin and charge generation material used, and the organic solvents include alcohols, sulfoxides, ketones, ethers, esters, aliphatic halogens. Hydrocarbons and aromatic compounds.

  The thickness of the charge generation layer is preferably 5 μm or less, and more preferably 0.01 to 1 μm.

  In addition, various sensitizers, antioxidants, ultraviolet absorbers, plasticizers, and the like can be added to the charge generation layer as necessary.

  The charge transport layer (charge transport layer that is not the surface layer of the electrophotographic photoreceptor) is formed by applying a charge transport layer coating solution obtained by dissolving a charge transport material and a binder resin in a solvent and drying. be able to. The ratio between the charge transport material and the binder resin is preferably in the range of 2: 1 to 1: 2 (mass ratio).

  Examples of the charge transport material include triarylamine compounds, hydrazone compounds, styryl compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds, and triarylmethane compounds. These charge transport materials may be used alone or in combination of two or more.

  Examples of the binder resin used for the charge transport layer include acrylic resin, acrylonitrile resin, allyl resin, alkyd resin, epoxy resin, silicone resin, nylon, phenol resin, phenoxy resin, butyral resin, polyacrylamide resin, polyacetal resin, polyamide. Imide resin, polyamide resin, polyallyl ether resin, polyarylate resin, polyimide resin, polyurethane resin, polyester resin, polyethylene resin, polycarbonate resin, polystyrene resin, polystyrene resin, polysulfone resin, polyvinyl butyral resin, polyphenylene oxide resin, polybutadiene resin, Examples include polypropylene resin, methacrylic resin, urea resin, vinyl chloride resin, and vinyl acetate resin. In particular, polyarylate resin, polycarbonate resin and the like are preferable. These can be used singly or in combination of two or more as a mixture or copolymer.

  Solvents used in the coating solution for the charge transport layer include ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate, ethyl acetate and n-butyl acetate, aromatic hydrocarbons such as toluene and xylene, 1,4- Ethers such as dioxane and tetrahydrofuran, and hydrocarbons substituted with halogen atoms such as chlorobenzene, chloroform and carbon tetrachloride are used.

  The thickness of the charge transport layer is preferably 5 to 40 μm, and more preferably 7 to 30 μm.

  In addition, an antioxidant, an ultraviolet absorber, a plasticizer, and the like can be added to the charge transport layer as necessary.

  Next, a layer containing a curable resin that becomes the surface layer of the electrophotographic photosensitive member will be described.

  A curable resin is made from a low molecular weight curable resin monomer / oligomer, and by applying energy such as heating or light irradiation from the outside, reactions such as addition and condensation proceed, resulting in a network structure that is insoluble and insoluble. It is a resin that is in a molten state (cured state).

  Examples of the curable resin include phenol resin, acrylic resin, epoxy resin, isocyanate resin, melamine resin, siloxane resin, unsaturated polyester resin, alkyd resin, urea resin, and the like. Among these, a phenol resin, an acrylic resin, an epoxy resin, an isocyanate resin, a melamine resin, and a siloxane resin are preferable from the viewpoint of strength as a binder resin for the surface layer. These can be used singly or in combination of two or more as a mixture or copolymer.

  The layer containing a curable resin that becomes the surface layer of the electrophotographic photosensitive member can be formed by applying and curing a coating solution obtained by dissolving a curable resin monomer / oligomer in a solvent.

  Examples of the solvent used in the coating solution include alcohols such as methanol, ethanol, and propanol, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate and n-butyl acetate, diethyl ether, diisopropyl ether, tetrahydrofuran, Examples include ethers such as dioxane, aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as cyclohexane and n-heptane, and halogenated hydrocarbons such as chlorobenzene, dichloromethane, chloroform, and carbon tetrachloride. Among these, alcohols that do not adversely affect the lower layer are preferred.

  Examples of the curable resin excellent in the solubility of the monomer / oligomer in alcohol include a phenol resin.

  Generally, a phenol resin is obtained by a reaction between phenols such as phenol, cresol, and xylenol, or polyhydric phenols such as biphenol, bisphenol A, and bisphenol F (collectively referred to as phenols) and aldehydes such as formaldehyde. The resulting resin. There are two types of phenolic resins: a resol type obtained by reacting phenols with an excess of aldehydes and an alkali catalyst, and an acid catalyst using phenols with an excess of aldehydes. It can be divided into novolak types. Among these phenol resins, a resol type phenol resin is preferable from the viewpoint of being one-component, alcohol-soluble, and easily curing a coating solution containing the resin.

  The resol type phenol resin is also soluble in alcohol and ketone solvents, and is heated and three-dimensionally cross-linked and cured to produce an insoluble and infusible tough structure (cured product).

  The surface layer of the electrophotographic photoreceptor preferably contains a charge transport material and / or conductive particles from the viewpoint of electrophotographic characteristics.

  As the charge transport material used for the surface layer of the electrophotographic photoreceptor, the same charge transport layer as that described above (a charge transport layer that is not the surface layer of the electrophotographic photoreceptor) can be used. Is preferable, and a charge transport material having a substituted or unsubstituted hydroxyalkyl group, a substituted or unsubstituted hydroxyalkoxy group, or a substituted or unsubstituted hydroxyphenyl group in the molecule is more preferable. .

  The conductive particles used for the surface layer of the electrophotographic photosensitive member include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, indium oxide doped with tin, tin oxide doped with antimony and tantalum. And metal oxide particles such as zirconium oxide doped with antimony, carbon black, and the like. Among these, metal oxide particles are preferable from the viewpoint of transparency of the surface layer, and tin oxide particles are more preferable from the viewpoint of dispersibility and electric resistance controllability. Further, the tin oxide particles may be subjected to a surface treatment described later.

  The average particle diameter of the conductive particles used for the surface layer of the electrophotographic photosensitive member is preferably 0.3 μm or less, and more preferably 0.1 μm or less, from the viewpoint of the transparency of the surface layer.

  The surface layer of the electrophotographic photosensitive member preferably contains lubricating particles from the viewpoint of improving the releasability of the surface of the electrophotographic photosensitive member. Among the lubricating particles, fluorine atom-containing resin particles, silicon atom-containing particles, and alumina particles are preferable, and fluorine atom-containing resin particles are more preferable. Fluorine atom-containing resin particles include tetrafluoroethylene resin, trifluoroethylene chloride resin, hexafluoroethylene propylene resin, vinyl fluoride resin, vinylidene fluoride resin, ethylene difluoride dichloride resin, Among these, particles of these copolymers are mentioned, and among these, tetrafluoroethylene resin particles and vinylidene fluoride resin particles are preferable.

  When conductive particles or lubricating particles are used for the surface layer of the electrophotographic photosensitive member, a method of dispersing them in the coating solution includes a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, a roll mill, a vibration mill, an attritor, a liquid A method using a collision type high-speed disperser can be mentioned.

  In the case where conductive particles and lubricating particles are included in the surface layer of the electrophotographic photosensitive member, the conductive particles are preferably surface-treated with a surface treatment agent such as a fluorine atom-containing compound or a siloxane compound. . By using the conductive particles surface-treated with these surface treatment agents, the dispersibility and dispersion stability of the conductive particles and the lubricating particles are improved. Examples of the fluorine atom-containing compound include a fluorine atom-containing silane coupling agent, a fluorine-modified silicone oil, and a fluorine atom-containing surfactant.

  Specific examples of the fluorine atom-containing silane coupling agent are given below.

  Specific examples of the fluorine-modified silicone oil are given below.

(In the formula (SO-1), n ^so1 and n ^so2 are each independently a positive integer.)

  Specific examples of the fluorine atom-containing surfactant will be given below.

In (the formula (SA-1) ~ (SA -25), X sa _{is, -CF 3, -C 4 F 9} , .R represents a monovalent fluorocarbon groups such as -C _{8 F 17} ^sa is An alkylene group, an arylene group or an alkylene arylene group, and when there are a plurality of R ^{sa s in the} formula, they may be the same or different.)

  The surface treatment of conductive particles using a fluorine atom-containing compound is roughly classified into two methods, a wet method and a dry method. In terms of the stability of the treatment reaction, ease of handling, etc., the method is wet. The method is preferred. When conducting the surface treatment of the conductive particles by a wet method, for example, it can be performed as follows.

  That is, the conductive particles before the surface treatment and the fluorine atom-containing compound are mixed and dispersed in a solvent, and the fluorine atom-containing compound is adhered to the surface of the conductive particles. Examples of the dispersion method include a dispersion method using a ball mill, a sand mill, or the like. After dispersion of the conductive particles, the solvent is removed from the dispersion, and the fluorine atom-containing compound is fixed to the surface of the conductive particles. Moreover, you may heat-process further after this as needed. Further, a catalyst for promoting the reaction may be added to the dispersion. Furthermore, you may further grind | pulverize the electroconductive particle after surface treatment as needed.

  The ratio of the fluorine atom-containing compound to the conductive particles is preferably 1 to 65% by mass, more preferably 1 to 50% by mass, based on the total mass of the conductive particles surface-treated with the fluorine atom-containing compound.

  In addition, even if it contains the said fluorine atom containing compound in the surface layer of an electrophotographic photoreceptor rather than as a surface treating agent of electroconductive particle, the effect similar to the above can be acquired.

  Further, by incorporating conductive particles surface-treated with a siloxane compound in the surface layer of the electrophotographic photosensitive member, the dispersibility and dispersion stability of the conductive particles and the lubricating particles are improved, and the surface layer of the electrophotographic photosensitive member is improved. Thus, the surface stability of the electrophotographic photosensitive member can be obtained.

  In addition, when the curable resin used for the surface layer of the electrophotographic photosensitive member is a phenol resin, streaky unevenness or cells may be formed when the surface layer of the electrophotographic photosensitive member is thickened. However, they can also be suppressed by incorporating conductive particles surface-treated with a siloxane compound in the surface layer of the electrophotographic photoreceptor.

  Specific examples of the siloxane compound are given below.

(In the above formula (SX-1), X ^sx represents a hydrogen atom or a methyl group. The plurality of X ^sx may be the same or different, but hydrogen for all of X ^sx (The atomic ratio is 0.1 to 50%, and n ^sx is a positive integer.)

  The weight average molecular weight of the siloxane compound having the structure represented by the formula (SX-1) is preferably 200 to 30000.

  The surface treatment of conductive particles using a siloxane compound is roughly classified into two methods, a wet method and a dry method. In terms of the stability of the treatment reaction and ease of handling, the wet method is used. preferable. When conducting the surface treatment of the conductive particles by a wet method, for example, it can be performed as follows.

  That is, the conductive particles before the surface treatment and the siloxane compound are mixed and dispersed in a solvent, and the siloxane compound is adhered to the surface of the conductive particles. Examples of the dispersion method include a dispersion method using a ball mill, a sand mill, or the like. After dispersion of the conductive particles, the solvent is removed from the dispersion, and the siloxane compound is fixed to the surface of the conductive particles. Moreover, you may heat-process further after this as needed. When heat treatment is performed, hydrogen atoms in the Si—H bond in the siloxane compound are oxidized by oxygen in the air to form a new siloxane bond. As a result, the siloxane compound has a three-dimensional structure (network structure), and the surfaces of the conductive particles are covered with the three-dimensional structure. Further, a catalyst for promoting the reaction may be added to the dispersion. Furthermore, you may further grind | pulverize the electroconductive particle after surface treatment as needed.

  The ratio of the siloxane compound to the conductive particles is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, based on the total mass of the conductive particles surface-treated with the siloxane compound.

  Note that the same effect as described above can be obtained even when the above siloxane compound is contained in the surface layer of the electrophotographic photosensitive member rather than as a surface treatment agent for conductive particles.

  In the present invention, the thickness of the surface layer of the electrophotographic photosensitive member containing a curable resin is preferably 0.1 to 10 μm, and more preferably 0.5 to 7 μm.

  In addition, an antioxidant, an ultraviolet absorber, a plasticizer, and the like can be added to the surface layer of the electrophotographic photoreceptor of the present invention as necessary. For example, the antioxidant is added for the purpose of preventing deterioration of the surface layer due to adhesion of active substances such as ozone and nitrogen oxide generated during charging.

  When applying the coating liquid for each of the above layers, for example, a coating method such as a dip coating method (dip coating method), a spray coating method, a spinner coating method, a roller coating method, a Meyer bar coating method, a blade coating method, or the like should be used. Can do.

  FIG. 2 shows an example of a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.

  In FIG. 2, reference numeral 1 denotes a cylindrical electrophotographic photosensitive member, which is driven to rotate at a predetermined peripheral speed in the direction of an arrow about an axis 2.

  The surface of the electrophotographic photosensitive member 1 that is rotationally driven is uniformly charged to a predetermined positive or negative potential by a charging unit (primary charging unit: charging roller or the like) 3, and then subjected to slit exposure, laser beam scanning exposure, or the like. Exposure light (image exposure light) 4 output from exposure means (not shown) is received. In this way, electrostatic latent images corresponding to the target image are sequentially formed on the surface of the electrophotographic photosensitive member 1.

  The electrostatic latent image formed on the surface of the electrophotographic photoreceptor 1 is developed with toner contained in the developer of the developing means 5 to become a toner image. Next, the toner image formed and supported on the surface of the electrophotographic photoreceptor 1 is transferred from a transfer material supply means (not shown) to the electrophotographic photoreceptor 1 and the transfer means by a transfer bias from a transfer means (transfer roller or the like) 6. 6 (contact portion) is sequentially transferred onto a transfer material (paper or the like) P taken out and fed in synchronization with the rotation of the electrophotographic photosensitive member 1.

  The transfer material P that has received the transfer of the toner image is separated from the surface of the electrophotographic photosensitive member 1 and introduced into the fixing means 8 to receive the image fixing, and is printed out as an image formed product (print, copy). Is done.

  The surface of the electrophotographic photosensitive member 1 after the transfer of the toner image is cleaned by a cleaning means (cleaning blade or the like) 7 to remove the developer (toner) remaining after transfer, and further from a pre-exposure means (not shown). After being subjected to charge removal processing by pre-exposure light (not shown), it is repeatedly used for image formation. As shown in FIG. 2, when the charging unit 3 is a contact charging unit using a charging roller or the like, pre-exposure is not necessarily required.

  Among the above-described components such as the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5, the transfer unit 6 and the cleaning unit 7, a plurality of components are housed in a container and integrally combined as a process cartridge. The process cartridge may be configured to be detachable from an electrophotographic apparatus main body such as a copying machine or a laser beam printer. In FIG. 2, the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5 and the cleaning unit 7 are integrally supported to form a cartridge, and the electrophotographic apparatus is used by using a guide unit 10 such as a rail of the electrophotographic apparatus main body. The process cartridge 9 is detachable from the main body.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to these. In the examples, “part” means “part by mass”.

(Example 1)
An aluminum cylinder (aluminum alloy of JIS A3003) having a diameter of 30 mm, a length of 260.5 mm, and a wall thickness of 1.5 mm was used as a support. The surface of this support was mirror finished.

  Next, 6 parts of the copolymerized polyamide resin (PA-4) (number average molecular weight: 20000) in Table 1 is dissolved in a mixed solvent of 66 parts of methanol / 1.8 parts of propanol to prepare a copolymerized polyamide resin solution. did.

  Next, a mixed solvent of 7 parts of titanium oxide particles having an average primary particle size of 35 nm (TTO55N, manufactured by Ishihara Sangyo Co., Ltd.) and 28 parts of methanol / 1 part of 12-propanol was dispersed in a sand mill for 24 hours. A titanium oxide particle dispersion was prepared.

  The copolymerized polyamide resin solution and the titanium oxide particles were mixed and dispersed with an ultrasonic disperser for 2 hours to prepare an intermediate layer coating solution.

  This intermediate layer coating solution was dip-coated on a support and dried at 100 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.8 μm.

  Next, a crystalline oxytinanium phthalocyanine having a structure represented by the following formula and having strong peaks at 9.6 ° and 27.3 ° with a Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction ( 4 parts of charge generating material)

2 parts of polyvinyl butyral resin (trade name: BX-1, manufactured by Sekisui Chemical Co., Ltd.) and 70 parts of cyclohexanone are dispersed for 10 hours in a sand mill using glass beads having a diameter of 1 mm, and then ethyl acetate 100 Part was added to prepare a coating solution for charge generation layer.

  This charge generation layer coating solution was dip-coated on the intermediate layer and dried at 90 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.25 μm.

  Next, 40 parts of a compound (charge transport material) having a structure represented by the following formula:

Further, 50 parts of bisphenol Z-type polycarbonate (trade name: Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) is dissolved in a mixed solvent of 300 parts of chlorobenzene / 50 parts of dimethoxymethane to obtain a coating solution for a charge transport layer. Prepared.

  This charge transport layer coating solution was dip coated on the charge generation layer and dried in hot air at 110 ° C. for 1 hour to form a charge transport layer having a thickness of 20 μm.

  Next, 100 parts of antimony-doped tin oxide particles (trade name: T-1, manufactured by Mitsubishi Materials Corporation, average particle size: 0.02 μm) are added to a fluorine atom-containing compound having a structure represented by the following formula (trade name) : LS-1090, manufactured by Shin-Etsu Chemical Co., Ltd.) 7 parts

(Hereinafter referred to as “treatment amount: 7%”).

  50 parts of the surface-treated antimony-doped tin oxide particles and 150 parts of ethanol were dispersed in a sand mill for 60 hours, and 20 parts of tetrafluoroethylene resin particles (number average particle size: 0.18 μm) were added. Further, the mixture was dispersed in a sand mill apparatus for 8 hours.

  Thereafter, 30 parts of a monomer / oligomer of a resol type phenolic resin (trade name: PL-4804, manufactured by Gunei Chemical Industry Co., Ltd.) was dissolved to prepare a coating solution for the surface layer. The dispersion state of the coating solution was good.

  The surface layer coating solution was dip coated on the charge transport layer and cured with hot air at 145 ° C. for 1 hour to form a layer having a thickness of 3 μm. The formed layer was a uniform film without unevenness.

  In this way, an electrophotographic photosensitive member in which the layer containing the curable resin was a surface layer was produced.

  The electrophotographic photosensitive member is mounted on a laser beam printer (trade name: LBP-NX: manufactured by Canon Inc.) remodeling machine (variable voltage applied to charging roller, variable exposure light amount), and electrophotographic characteristics Was evaluated. The charge was set so that the dark part potential was −700 V, and this was irradiated with laser light having a wavelength of 780 nm, and the amount of light necessary to reduce the potential of −700 V to −200 V was measured. . The sensitivity was measured after outputting 5000 images in an initial environment and a low temperature and low humidity (15 ° C./10% RH) environment. When measuring the surface potential of the electrophotographic photosensitive member, an electrometer probe was installed in place of the developing device.

  In addition, as an evaluation of ghost, an appropriate character pattern is printed for one turn of the electrophotographic photosensitive member in an initial environment in a normal temperature and normal humidity (23 ° C./55% RH) environment, and then a full-tone image is output. It was confirmed whether or not a ghost was generated. As the image sample, an entire black image and an image having a density of one dot and one space were used, and sampled at densities F5 (center value) and F9 (the lightest density) that can be set by the printer. The evaluation criteria are as follows.

A: A ghost is not visible under any conditions B: An image with a density of 1 dot 1 space, a ghost is visible at a density F9 C: An image with a density of 1 dot 1 space, a ghost is visible at a density F5 D: Full black image, density Ghost appears at F9 E: Full black image, ghost appears at density F5

  In addition, a part of the surface of the electrophotographic photosensitive member is rubbed and charged with urethane rubber for 1 minute, and is left to stand for 3 days to output an image. Observed.

  Further, the amount of abrasion on the surface of the electrophotographic photosensitive member is determined after an initial film thickness and 5000 images are output using an eddy current film thickness measuring device (trade name: Permascope, manufactured by Fisher Instruments). It calculated | required from the difference with the film thickness of.

  The evaluation results are shown in Table 2.

(Example 2)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the surface layer was formed as follows. The evaluation results are shown in Table 2.

  That is, 100 parts of antimony-doped tin oxide particles (trade name: T-1, manufactured by Mitsubishi Materials Corporation, average particle size: 0.02 μm), a fluorine atom-containing compound having a structure represented by the following formula (trade name: LS) -1090, Shin-Etsu Chemical Co., Ltd.) 7 parts,

And 250 parts of ethanol was stirred with a stirrer for 48 hours, filtered, washed, and then heat-treated at 150 ° C. for 2 hours to perform surface treatment of the antimony-doped tin oxide particles.

  45 parts of the surface-treated antimony-doped tin oxide particles, 18 parts of an acrylic resin monomer having a structure represented by the following formula,

6.8 parts of 2-methylthioxanthone (photoinitiator), 14 parts of tetrafluoroethylene resin particles (number average particle size: 0.18 μm), and 150 parts of ethanol were dispersed for 90 hours in a sand mill apparatus, A coating solution for the layer was prepared.

This coating solution for the surface layer is dip-coated on the charge transport layer, dried, and then cured by irradiating with an ultraviolet ray having a light intensity of 250 W / cm ^{2 with} a high-pressure mercury lamp for 60 seconds, and then at 120 ° C. for 2 hours. The film was dried with hot air to form a layer having a thickness of 3 μm.

  In this way, an electrophotographic photosensitive member in which the layer containing the curable resin was a surface layer was produced.

(Example 3)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the surface layer was formed as follows. The evaluation results are shown in Table 2.

  That is, 26 parts of tetrafluoroethylene resin particles (number average particle size: 0.18 μm), fluorine atom-containing compound having a structure represented by the following formula (trade name: LS-1090, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 Part,

And 300 parts of ethanol was disperse | distributed for 60 hours with the sand mill apparatus, and the tetrafluoroethylene resin particle dispersion liquid was prepared.

  164 parts of this tetrafluoroethylene resin particle dispersion, 40 parts of monomer / oligomer of resol type phenol resin (trade name: PL-4852, manufactured by Gunei Chemical Industry Co., Ltd., nonvolatile component: 75%), and the following formula 21 parts of a compound (charge transport material) having the structure shown by

Were mixed and stirred for 4 hours to prepare a coating solution for the surface layer.

  The surface layer coating solution was dip coated on the charge transport layer and cured with hot air at 145 ° C. for 1 hour to form a layer having a thickness of 3 μm.

  In this manner, an electrophotographic photosensitive member in which the layer containing the curable resin (second charge transport layer) was a surface layer was produced.

Example 4
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the surface layer was formed as follows. The evaluation results are shown in Table 2.

  That is, the same surface-treated antimony-doped tin oxide particles 50 parts as in Example 1 and a mixed solvent of ethanol 170 parts / 2-propanol 100 parts were dispersed in a sand mill device for 66 hours to obtain a tin oxide particle dispersion. Prepared.

  In this tin oxide particle dispersion, 30 parts of a thermosetting epoxy resin monomer having a structure represented by the following formula,

And 7 parts of an acid anhydride (curing catalyst) represented by the following formula

Was added to prepare a coating solution for the surface layer.

  This coating solution for the surface layer was dip-coated on the charge transport layer and cured by heat treatment at 80 ° C. for 30 minutes and then at 130 ° C. for 2 hours to form a layer having a thickness of 3 μm.

  In this way, an electrophotographic photosensitive member in which the layer containing the curable resin was a surface layer was produced.

(Example 5)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the surface layer was formed as follows. The evaluation results are shown in Table 2.

  That is, 10 parts of a compound (charge transport material) having a structure represented by the following formula:

And 20 parts of a solution of a modified burette having a structure represented by the following formula (12) (solid content: 67% by mass)

Was dissolved in a mixed solvent of 350 parts of tetrahydrofuran / 150 parts of cyclohexanone to prepare a coating solution for the surface layer.

  This coating solution for the surface layer was spray-coated on the charge transport layer, allowed to stand at room temperature for 30 minutes, and then cured with hot air at 145 ° C. for 1 hour to form a layer having a thickness of 3 μm.

  In this manner, an electrophotographic photosensitive member in which the layer containing the curable resin (second charge transport layer) was a surface layer was produced.

(Comparative Example 1)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the intermediate layer was formed as follows. The evaluation results are shown in Table 2.

  That is, Example 1 except that the titanium oxide particles having an average primary particle size of 35 nm used in the intermediate layer coating solution were changed to titanium oxide particles having an average primary particle size of 210 nm (CR-60, manufactured by Ishihara Sangyo Co., Ltd.). In the same manner as described above, an intermediate layer coating solution was prepared.

  This intermediate layer coating solution was dip-coated on a support and dried at 100 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.8 μm.

(Comparative Example 2)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the intermediate layer was formed as follows. The evaluation results are shown in Table 2.

  That is, for the intermediate layer in the same manner as in Example 1, except that the copolymerized polyamide resin used in the coating solution for the intermediate layer was changed to a polyamide resin (Daiamide T-171, manufactured by Daicel Huls) outside the scope of the present invention. A coating solution was prepared.

  This intermediate layer coating solution was dip-coated on a support and dried at 100 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.8 μm.

(Comparative Example 3)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the intermediate layer was formed as follows. The evaluation results are shown in Table 2.

  That is, an intermediate layer coating solution was prepared in the same manner as in Example 1 except that the intermediate layer coating solution did not contain titanium oxide particles having an average primary particle size of 35 nm.

  This intermediate layer coating solution was dip-coated on a support and dried at 100 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.8 μm.

(Comparative Example 4)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that no intermediate layer was provided between the support and the charge generation layer. The evaluation results are shown in Table 2.

(Comparative Example 5)
In Example 1, an electrophotographic photosensitive member was produced and evaluated in the same manner as in Example 1 except that the surface layer was formed as follows. The evaluation results are shown in Table 2.

  That is, 50 parts of surface-treated antimony-doped tin oxide particles and 150 parts of 1,4-dioxane as in Example 1 were dispersed for 66 hours in a sand mill apparatus, and further, tetrafluoroethylene resin particles (number average particles) (Diameter: 0.18 μm) 20 parts were added, and the mixture was further dispersed for 12 hours in a sand mill.

  Thereafter, 30 parts of a polycarbonate resin (Iupilon Z-800, manufactured by Mitsubishi Gas Chemical Co., Ltd.), which is a thermoplastic resin, was dissolved and dispersed in a sand mill apparatus for 1 hour to prepare a coating solution for the surface layer.

  The coating solution for the surface layer was spray-coated on the charge transport layer and dried with hot air at 100 ° C. for 30 minutes to form a layer having a thickness of 3 μm.

  In this way, an electrophotographic photosensitive member in which the layer containing the thermoplastic resin was a surface layer was produced.

(Comparative Example 6)
In Example 1, an electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that a layer containing a curable resin was not provided on the charge transporting layer and the charge transporting layer was a surface layer of the electrophotographic photosensitive member. Prepared and evaluated. The evaluation results are shown in Table 2.

  In Comparative Examples 5 and 6, the surface scraping after outputting 5000 images reached the charge transport layer.

It is a figure which shows the example of a layer structure of the electrophotographic photoreceptor of this invention. 1 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having the electrophotographic photosensitive member of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Support body 103 Intermediate | middle layer 104 Single layer type photosensitive layer 105 Layer containing curable resin 1041 Charge generation layer 1042 Charge transport layer 105 'Layer containing curable resin 1 Electrophotographic photoreceptor 2 Axis 3 Charging means 4 Exposure light DESCRIPTION OF SYMBOLS 5 Developing means 6 Transfer means 7 Cleaning means 8 Fixing means 9 Process cartridge 10 Guide means P Transfer material

Claims (16)

In an electrophotographic photosensitive member having an intermediate layer and a photosensitive layer in this order on a support,
The surface layer of the electrophotographic photoreceptor contains a curable resin,
The electrophotographic photoreceptor, wherein the intermediate layer contains a copolymerized polyamide resin having a repeating structural unit represented by the following formula (1) and titanium oxide particles having an average primary particle size of 100 nm or less.

(In formula (1), R ¹⁰¹ and R ¹⁰² each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted aryl group. Ar ¹⁰¹ and Ar ¹⁰² each independently represent a substituted or unsubstituted cyclohexylene group or a substituted or unsubstituted cyclohexylidene group.   The curable resin contained in the surface layer of the electrophotographic photosensitive member is at least one curable resin selected from the group consisting of a phenol resin, an acrylic resin, an epoxy resin, an isocyanate resin, a melamine resin, and a siloxane resin. The electrophotographic photosensitive member according to claim 1.   The electrophotographic photosensitive member according to claim 2, wherein the phenol resin is a resol type phenol resin.   The electrophotographic photosensitive member according to claim 1, wherein the surface layer of the electrophotographic photosensitive member contains conductive particles.   The electrophotographic photosensitive member according to claim 4, wherein the conductive particles contained in the surface layer of the electrophotographic photosensitive member are metal oxide particles.   The electrophotographic photosensitive member according to claim 5, wherein the metal oxide particles are tin oxide particles.   The electrophotographic photosensitive member according to claim 1, wherein the surface layer of the electrophotographic photosensitive member contains a charge transport material.   The electrophotographic photosensitive member according to claim 7, wherein the charge transporting material contained in the surface layer of the electrophotographic photosensitive member is a charge transporting material having a hydroxy group in the molecule.   The charge transport material having a hydroxy group in the molecule is at least one selected from the group consisting of a substituted or unsubstituted hydroxyalkyl group, a substituted or unsubstituted hydroxyalkoxy group, and a substituted or unsubstituted hydroxyphenyl group. The electrophotographic photosensitive member according to claim 8, which is a charge transport material having one group in the molecule.   The electrophotographic photosensitive member according to claim 1, wherein the surface layer of the electrophotographic photosensitive member contains lubricating particles.   11. The lubricating particles contained in the surface layer of the electrophotographic photosensitive member are at least one particle selected from the group consisting of fluorine atom-containing resin particles, silicon atom-containing particles, and alumina particles. Electrophotographic photoreceptor.   The surface layer of the electrophotographic photosensitive member contains at least one selected from the group consisting of a fluorine atom-containing silane coupling agent, a fluorine-modified silicone oil, a fluorine atom-containing surfactant, and a siloxane compound. The electrophotographic photosensitive member according to any one of -11. The electrophotographic photosensitive member according to claim 1, wherein the repeating structural unit represented by the formula (1) is a repeating structural unit represented by the following formula (2).

(In the formula ^(2), R ^{101, R 102} has the same meaning as ^{R 101, R 102} of each of the formulas (1), each independently, a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted R ^{201 to} R ²²⁰ each independently represents a hydrogen atom or a monovalent substituent.   The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains at least one selected from the group consisting of oxytitanium phthalocyanine, chlorogallium phthalocyanine, and hydroxygallium phthalocyanine.   15. An electrophotographic apparatus main body integrally supporting the electrophotographic photosensitive member according to claim 1 and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, and a cleaning means. A process cartridge that is detachable.   An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an exposure unit, a developing unit, and a transfer unit.

Images