Electrophotographic photoreceptor

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a highly sensitive and highly reliable electrophotographic photosensitive member. More specifically, the present invention relates to an electrophotographic photosensitive member having a cured film formed by using an organometallic compound and an electron-accepting compound as an undercoat layer.

【0002】

[Conventional technology]

Electrophotographic apparatus has high speed and high print quality, and is used in fields such as copiers and laser beam printers. As a photoconductor used in an electrophotographic apparatus, an organic photoconductor (OPC) using an organic photoconducting material has been developed and is widely used. In addition, the structure of the photoconductor is changed from a single-layer photoconductor in which a charge-transfer complex structure or a charge-generating material is dispersed in a binder resin to a function-separated photoconductor in which a charge-generating layer and a charge-transporting layer are separated. The performance has improved. Currently, the mainstream of this function-separated photoconductor has a structure in which an undercoat layer is first formed on an aluminum substrate, and then a charge generation layer and a charge transport layer are formed. With the progress of electrophotographic apparatus, higher quality image quality is required for the performance of the photoconductor. In order to improve the repeatability and environmental stability of the photoconductor, all of the charge generation layer, charge transport layer and undercoat layer are important for each of the electrophotographic characteristics such as sensitivity, image quality and repeatability. Influencing.

【0003】

Conventionally, regarding the formation of an undercoat layer or an intermediate layer using a curable compound that is polycondensed by hydrolysis of an organometallic compound, for example, JP-A-59-22438, JP-A-61-94057, JP-A-P. It is described in No. 2-59767, No. 3-18858, No. 4-124674, No. 4-145416, No. 4-162047, etc., and is publicly known.

【0004】

[Problems to be Solved by the Invention]

Of the carriers generated in the charge generation layer, holes move through the charge transport layer and recombine with the surface charge, but electrons need to move through the undercoat layer and recombine with the induced charge on the substrate. is there. However, when the transportability of electrons in the undercoat layer is low, the electrons remain localized in the undercoat layer or at the interface with the charge generation layer, and the residual potential rises when the photoconductor is used repeatedly. And image quality defects occur. Therefore, it is necessary to impart high electron transportability to the undercoat layer. However, when the undercoat layer is formed by using a coating solution for forming an undercoat layer in which a low molecular weight electron transporting material such as trinitrofluorenone or a diphenoquinone compound is dissolved in a polymer binder resin, the charge of the upper layer is generated. At the time of film formation of the layer or the charge transport layer, low molecular weight components were eluted and mixed with the upper layer, causing secondary damage in electrical characteristics and often impairing the uniformity of the coating film. Further, in the case of an electrophotographic photosensitive member having an undercoat layer formed by using the above-mentioned curable compound, it was not sufficiently satisfactory in terms of electrical characteristics.

【0005】

The present invention has been made for the purpose of improving the above-mentioned problems in the prior art. Therefore, an object of the present invention is to provide an electrophotographic photosensitive member having an improved undercoat layer and excellent in sensitivity, image quality and repeatability.

【0006】

[Means for solving problems]

In view of the above points, the present inventor has investigated an undercoat layer having higher sensitivity, image quality and repeatability, and as a result, a cured film containing an electron-accepting compound and an organometallic compound has been obtained. It has been found that the above object can be achieved by using the pulling layer, and the present invention has been completed. That is, the electrophotographic photosensitive member of the present invention is obtained by sequentially laminating a charge generation layer and a charge transport layer on a conductive support, and an organometallic compound and an organometallic compound between the conductive support and the charge generation layer. It is characterized by having a cured film formed of one or both of the silane coupling agents, an electron-accepting compound, and a binder resin as an undercoat layer. In the present invention, the electron-accepting compound is preferably an electron-transporting material.

【0007】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the laminated electrophotographic photosensitive member of the present invention will be described in detail. As the conductive support, in addition to metals such as copper, aluminum, nickel, and iron, plastic or paper that has been conductively treated by depositing a metal on the surface or forming a coating film in which conductive powder is dispersed is used. The formed tubular, belt-shaped and sheet-shaped substrates can be used. Further, in order to prevent interference fringes, the surface of the conductive support can be roughened by using methods such as etching, anodic oxidation, wet blasting, sand blasting, rough cutting, and centerless grinding. ..

【0008】

An undercoat layer is formed on the surface of the conductive support for the purpose of stabilizing electrical characteristics, preventing image quality defects, improving chargeability, improving adhesion, etc., but the undercoat layer in the present invention is , An organometallic compound and one or both of a silane coupling agent, an electron-accepting compound, and a cured film formed of a binder resin. By performing a curing treatment using an organometallic compound or a silane coupling agent in the undercoat layer, low-molecular-weight electron-accepting compounds do not elute when the upper layer is applied, resulting in a more stable and excellent electrophotographic photosensitive member. Can be formed. Further, when an organometallic compound or a silane coupling agent is used, excellent electrophotographic properties that cannot be obtained when they are not used in combination can be obtained. Further, excellent electrophotographic characteristics such as high photoattenuation and low residual potential in the electrophotographic photosensitive member of the present invention cannot be obtained by using other curable resins.

【0009】

As the electron accepting compound used for the undercoat layer of the present invention, for example, the following can be used. That is, quinones such as 2,5-dihydroxy-p-quinone; 1,2-dihydroxyanthraquinone, 1,5-dihydroxyanthraquinone, 1,8-dihydroxyanthraquinone, 1-aminoanthraquinone, anthraquinone-2,2-dicarboxylic acid. , Anthraquinones such as nitroanthraquinone, dinitroanthraquinone, quinizarin, 2,3-dihydroxykinizarin; 2,6-naphthoquinone, 2-hydroxy-1,4-naphthoquinone, 5,8-dihydroxy-1,4-naphthoquinone, etc. Naphthoquinones; o-benzoquinone, p-benzoquinone, methoxybenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dichloro-5,6-dicyano-p-benzoquinone, anthraquinone, etc. Benthraquinones; pyrimidines such as 4,6-dihydroxypyrimidine; 3,3', 5,5'-tetra-tert-butyl-4,4'-diphenoquinone, 3,5'-di-tert-butyl-3' , 5-Diphenyl-4,4-diphenoquinone, 3,5-dimethyl-3,5-di-tert-butyl-4,4-diphenoquinone, 3,5-diphenyl-3,5-di -tert-butyl-4,4-diphenoquinone, 3,5-dimethoxy-3,5-di-tert-butyl-4,4-diphenthraquinone, 3,3,5,5-tetra-t -Butyl-4,4'-diphenoquinone, 3,5'-bis (α, α, γ, γ-tetramethylbutyl) -3', 5-di (α-methylpropyl) -4,4'-diphenthraquinone, 3,5-bis (α, α, γ, γ-tetramethylbutyl) -3', 5'-di (α-methylpropyl) -4,4'-diphenoquinone, 3,5'-bis (α, α) , γ, γ-Tetramethylbutyl) -3', 5-diphenyl-4,4'-diphenoquinone, 3,5'-bis (α, γ-dimethylbutyl) -3', 5-diphenyl-4,4' -Diphenoquinone, 3,

【0010】

When the structure has one or more hydrolyzable polymerizable substituents, a more curable coating film is formed. Examples of the hydrolyzable polymerizable group include an alkoxyl group such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a t-butoxy group and a hexyloxy group, and a hydroxyl group. Among these electron-accepting compounds, fluorenone-based compounds, diphenoquinone-based compounds, and anthracinodimethane-based compounds have excellent charge transport properties, and preferable properties can be obtained.

【0011】

Further, in the undercoat layer of the present invention, either one or both of the organometallic compound and the silane coupling agent are used in combination with the electron-accepting compound. These compounds can be used alone or as a mixture of multiple compounds or as a polycondensate. Among them, the zirconium-containing organic compound or silane coupling agent has high film-forming properties, has a low residual potential, has a small potential change due to the environment, and has a small potential change due to repeated use, and is excellent in performance.

【0012】

Examples of the organometallic compound that can be used in the present invention include organometallic compounds containing zirconium, titanium, aluminum, manganese and the like. The following are exemplified as specific examples thereof. Examples of organic zirconium compounds include zirconium butoxide, ethyl zirconium acetoacetate, zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl acetate zirconium butoxide, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octanate, Examples thereof include zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, zirconium methacrylate butoxide, stearate zirconium butoxide, and isosterate zirconium butoxide.

【0013】

Examples of organic titanium compounds include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate, titanium. Examples thereof include lactate ammonium salt, titanium lactate ethyl ester, titanium triethanolaminate, and polyhydroxytitanium stearate.

【0014】

Examples of organoaluminum compounds include aluminum isopyrate, monobutoxyaluminum diisopropilate, aluminum butyrate, diethylacetacetate, aluminumdiisopropirate, aluminum tris (ethylacetacetate) and the like.

【0015】

The organometallic compound containing zirconium, titanium, aluminum, and silicon shown here is a compound having hydrolytic condensability, and a coating film that has been cured can be obtained by applying a humidification treatment in the curing step.

【0016】

Examples of silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-β- (methoxyethoxysilane), γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyl-tris (β-methoxyethoxy). ) Silane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl)- γ-Aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, N, N-bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, N-phenyl-γ -Aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane and the like can be mentioned. Among these, particularly preferably used silane compounds are vinyltriethoxysilane, vinyltris-β- (methoxyethoxysilane), γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3). , 4-Epoxycyclohexyl) ethyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyl Dimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane and the like.

【0017】

The electron-accepting compound is blended in the range of 0.1 to 98% by weight, preferably 5 to 90% by weight, based on the total amount of the electron-accepting compound, the organometallic compound and the silane coupling agent.

【0018】

As the binder resin used for the undercoat layer, acetal resin such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, etc. Polymer compounds such as polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride strong filler resin, silicone resin, silicone alkyd resin, phenolformaldehyde resin, and melamine resin can be used. The binder resin can be used in the range of 1 to 95% by weight, preferably 5 to 90% by weight, based on the total solid content of the undercoat layer.

【0019】

Various organic or inorganic fine powders can be mixed in the undercoat layer for the purpose of preventing interference fringes and improving the electrical characteristics. In particular, white pigments such as titanium oxide, zinc oxide, zinc oxide, zinc sulfide, lead white, and lithopone, extender pigments such as alumina, calcium carbonate, and barium sulfate, or teflon resin particles, benzoguanamine resin particles, and styrene resin particles are effective. Is. When blending fine powder, it can be blended in the range of up to 90% by weight. The particle size of the fine powder to be added is preferably in the range of 0.01 μm to 2 μm. If the particle size is too large, the undercoat layer becomes uneven and the partial non-uniformity becomes large electrically, so that image quality defects are likely to occur. Further, if the particle size is too small, a sufficient light scattering effect cannot be obtained.

【0020】

In general, when the film thickness of the undercoat layer is increased, the concealing property of the unevenness of the base material is increased, so that the image quality defect is reduced, but on the other hand, the electrical repeatability is also deteriorated. Therefore, it is desirable that the film thickness of the undercoat layer is in the range of 0.1 to 5 μm. The undercoat layer in the present invention becomes a strong cured film that does not dissolve when the upper layer is formed by the coating liquid by undergoing a drying and curing treatment after coating. Usually, the undercoat layer is cured by drying at a temperature in the range of 40 ° C to 200 ° C for 3 minutes to 8 hours. By making the reaction of the hydrolyzable reactive group used in the present invention more robust, better electrical stability and image quality can be obtained, but in order to allow the hydrolyzable reaction to proceed more reliably, Humidification treatment may be added during the drying process. The humidification treatment is performed by applying moist hot air to the surface of the coating film. It is desirable that the wet hot air used at that time has a temperature between 30 and 180 ° C.

【0021】

The charge generation layer provided on the undercoat layer is formed by forming a charge generation material by vacuum deposition or by dispersing and coating the charge generation material together with an organic solvent and a binder resin. Charge generating materials include amorphous selenium, crystalline selenium, selenium-tellu alloy, selenium-arsenic alloy, other selenium compounds and selenium alloys, inorganic photoconductors such as zinc oxide and titanium oxide, and metal-free phthalocyanines. Various phthalocyanine pigments such as titanyl phthalocyanine, copper phthalocyanine, tin phthalocyanine, gallium phthalocyanine, various organic pigments and dyes such as squarerium-based, antoanthron-based, perylene-based, azo-based, anthraquinone-based, pyrene-based, pyrylium salt, thiapyrylium salt, etc. Used. Further, these organic pigments generally have several kinds of crystal types, and in particular, in the case of phthalocyanine pigments, various crystal types such as α type and β type are known, but depending on the purpose. Any of these crystal forms can be used as long as it is a pigment that can obtain sensitivity. For the charge generation layer, a silane coupling agent or an organometallic alkoxide can be used for various purposes such as prevention of aggregation of the charge generation material, improvement of dispersibility, and improvement of electrical characteristics. When these substances are added, the charge generating material may be surface-treated with these substances in advance and then treated with a dispersion liquid, or a silane coupling agent or an organometallic alkoxide may be added to the coating liquid.

【0022】

Examples of the binder resin in the charge generation layer include the following. For example, polycarbonate resin such as bisphenol A type or bisphenol Z type, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polystyrene resin, polyvinyl acetate resin, styrene-butadiene copolymer resin, vinylidene chloride-acrylonitrile copolymer. Examples thereof include resins, vinyl chloride-vinyl acetate-maleic anhydride copolymer resins, silicon resins, silicone-alkyd resins, phenol-formaldehyde resins, styrene-alkyd resins, poly-N-vinylcarbazole and the like. These binder resins can be used alone or in combination of two or more. The blending ratio (weight ratio) of the charge generating material and the binder resin is preferably in the range of 10: 1 to 1:10. The thickness of the charge generation layer is generally set in the range of 0.01 to 5 μm, preferably 0.05 to 2.0 μm.

【0023】

As a method of dispersing the charge generating material in the resin, a method using a roll mill, a ball mill, a vibration mill, an attritor, a sand mill, a colloid mill or the like can be adopted. The solvent used at that time is methanol. , Ethanol, propanol, alcohols such as n-butyl alcohol, esters such as ethyl acetate and butyl acetate, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and 1,2-dichloroethane, etc. Can be given.

【0024】

A charge transport layer is provided on the charge generation layer, and the charge transport layer is composed of a charge transport material and, if desired, a binder resin. Examples of the charge transport material used for the charge transport layer include those shown below. Oxaziazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenyl-pyrazolin, 1- [pyridyl- (2)]-3 -(P-diethylaminostyryl) -5- (p-diethylaminostyryl) Pyrazoline derivatives such as pyrazoline, triphenylamine, tri (p-methylphenyl) amine, N, N-bis (3,4-dimethylphenyl) biphenyl- Aromatic tertiary amino compounds such as 4-amine and dibenzylaniline, N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1-biphenyl] -4,4'- Aromatic tertiary diamino compounds such as diamine, 1,2,4- such as 3- (4'-dimethylaminophenyl) -5,6-di (4'-methoxyphenyl) -1,2,4-triazine Triazine derivatives, hydrazone derivatives such as 4-diphenylaminobenzaldehyde-1,1-diphenylhydrazone, quinazoline derivatives such as 2-phenyl-4-styryl-quinazoline, 6-hydroxy-2,3-di (p-methoxyphenyl) -benzofurans Benzofuran derivatives such as p- (2,2-diphenylvinyl) -N, N-diphenylaniline and other α-stilben derivatives, enamine derivatives, carbazole derivatives such as N-ethylcarbazole, poly-N-vinylcarbazole and its derivatives. Hole transporting substances such as. Quinone compounds such as chloranil, bromoanil and anthraquinone, tetracyanoquinodimethane compounds, 2,4,7-trinitrofluorenone, 2,4,5, Electron transport substances such as fluorenone compounds such as 7-tetranitro-9-fluorenone, xanthone compounds, thiophene compounds, and diphenoquinone compounds. Further, a polymer or the like having a group composed of the above-mentioned compound in the main chain or the side chain can also be used. The above charge transport materials may be used alone or in combination of two or more.

【0025】

Examples of the binder resin used for the charge transport layer include acrylic resin, polyarylate, polyester resin, polycarbonate resin such as bisphenol A type or bisphenol Z type, polystyrene, acrylonitrile-styrene copolymer, and acrylonitrile-butadiene copolymer. , Polyvinyl butyral, polyvinyl formal, polysulfone, polyacrylamide, polyamide, insulating resin such as chlorine rubber, and organic photoconductive polymers such as polyvinylcarbazole, polyvinylanthracene, and polyvinylpyrene.

【0026】

The charge transport layer can be formed by applying a solution in which the charge transport material and the binder resin shown above are dissolved in an appropriate solvent and drying. Examples of the solvent used for forming the charge transport layer include aromatic hydrocarbons such as benzene, toluene and chlorobenzene, ketones such as acetone and 2-butanone, and halogenation of methylene chloride, chloroform and ethylene chloride. Aliphatic hydrocarbons, cyclic or linear ethers such as tetrahydrofuran, dioxane, ethylene glycol and diethyl ether, or mixed solvents thereof and the like can be used. The blending ratio of the charge transport material and the binder resin is preferably 10: 1 to 1: 5.

【0027】

Additives such as antioxidants, light stabilizers, and heat stabilizers are added to the charge transport layer for the purpose of preventing deterioration of the photoconductor due to ozone, oxidizing gas, or light / heat generated in the electrophotographic apparatus. can do. For example, examples of the antioxidant include hindered phenol, hindered amine, paraphenylenediamine, aryl alkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, organic sulfur compounds, organic phosphorus compounds and the like.

【0028】

Examples of the light stabilizer include derivatives such as benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine. Further, an electron-accepting substance can be contained for the purpose of improving sensitivity, reducing residual potential, reducing fatigue during repeated use, and the like. Examples of the electron-accepting substance that can be used in the electrophotographic photosensitive member of the present invention include succinic anhydride, maleic anhydride, dibrom phthalic anhydride, phthalic anhydride, tetrabrom phthalic anhydride, tetracyanoethylene, and tetracyanokinodi. Examples thereof include methane, o-dinitrobenzene, m-dinitrobenzene, chloranyl, dinitroanthraquinone, trinitrofluorenone, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid and phthalic acid. Of these, fluorenone, quinone, Cl, CN, NO₂A benzene derivative having an electron-withdrawing substituent such as, etc. can be particularly preferably used.

【0029】

The coating can be performed by using a coating method such as a dip coating method, a spray coating method, a bead coating method, a plate coating method, or a roller coating method. It is desirable to perform heat drying at a temperature of 30 ° C to 200 ° C for a time in the range of 5 minutes to 2 hours. The film thickness of the charge transport layer is generally set in the range of 5 to 50 μm, preferably 10 to 40 μm.

【0030】

A surface protective layer can be formed on the charge transport layer, if necessary. As the surface protective layer, there is an insulating resin protective layer or a low resistance protective layer in which a resistance adjusting agent is added to the insulating resin. In the case of a low resistance protective layer, for example, a layer in which conductive fine particles are dispersed in an insulating resin can be mentioned. As conductive fine particles, electrical resistance is 10⁹Fine particles having an average particle size of 0.3 μm or less, preferably 0.1 μm or less, which are Ω · cm or less and exhibit white, gray or bluish white, are preferably used. For example, molybdenum oxide, tungsten oxide, antimony oxide, tin oxide, titanium oxide, indium oxide, a solid solution of tin oxide and antimony or antimony oxide, or a mixture thereof, or a mixture of these metal oxides in a single particle. Things, or covered things, etc. can be mentioned. Among them, a solid solution of tin oxide or tin oxide and antimony or antimony oxide is preferably used because the electric resistance can be appropriately adjusted and the protective layer can be made substantially transparent. (Refer to JP-A-57-30847 and JP-A-57-128344). Examples of the insulating resin include condensed resins such as polyamide, polyurethane, polyester, epoxy resin, polyketone and polycarbonate, and vinyl polymers such as polyvinylketone, polystyrene and polyacrylamide.

【0031】

The electrophotographic photosensitive member of the present invention can be used in electrophotographic devices such as light lens copiers, laser beam printers that emit near-infrared light or visible light, digital copiers, LED printers, and laser facsimiles. .. Further, the electrophotographic photosensitive member of the present invention can be applied to a method using any of a one-component system, a two-component normal developer and a reverse developer. Further, the electrophotographic photosensitive member of the present invention can obtain good characteristics with less current leakage even when a contact charging method using a charging roller, a charging brush or the like is applied.

【0032】

[Example]

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. Example 1 3 parts by weight of polyvinyl butyral resin (Sekisui Chemical Co., Ltd. Eslek BM-S) is dissolved in 10 parts by weight of toluene, and further 3,3', 5,5'-tetra-t-butyl-4,4'-diphenoquinone 5 The weight part was dissolved. 40 parts by weight of a 50% by weight solution of an organic zirconium compound (zirconium tetrabutyrate) was added dropwise to this solution, mixed with stirring, and filtered to obtain a coating liquid for forming an undercoat layer. This coating liquid is applied by ring coating on a 30 mmφ aluminum substrate roughened by liquid honing treatment, air-dried at room temperature for 5 minutes, and then dried and cured at 170 ° C for 10 minutes. An undercoat layer having a film thickness of 1 μm was formed.

【0033】

As a charge generating material, a mixture consisting of 15 parts by weight of gallium phthalocyanine chloride, 10 parts by weight of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nippon Unicar Co., Ltd.) and 300 parts by weight of n-butyl alcohol was dispersed in a sand mill for 4 hours. .. The obtained dispersion was immersed and coated on the undercoat layer and dried to form a charge generation layer having a film thickness of 0.2 μm. Next, N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine 4 parts by weight and bisphenol Z polycarbonate resin (molecular weight 40,000) ) 6 parts by weight and 80 parts by weight of chlorobenzene were added and dissolved. Using the obtained solution, a charge transport layer having a film thickness of 20 μm was formed by coating and drying, and an electrophotographic photosensitive member composed of three layers was prepared. The obtained electrophotographic photosensitive member was charged to -700 V using an electrical characteristic evaluation device, and then exposed to a predetermined amount of light to measure the potential. The results are shown in Table 1.

【0034】

Comparative example 1 3 parts by weight of polyvinyl butyral resin is dissolved in 10 parts by weight of toluene, 43 parts by weight of a 50% by weight toluene solution of an organic zirconium compound (zirconium tetrabutyrate) is added dropwise, mixed by stirring, and filtered to form an undercoat layer. A coating solution was obtained. Using this coating liquid, an electrophotographic photosensitive member composed of an undercoat layer, a charge generation layer and a charge transport layer was prepared by the method shown in Example 1. Table 1 shows the results of the electrical characteristics evaluated using the obtained electrophotographic photosensitive member.

【0035】

Comparative example 2 3 parts by weight of polyvinyl butyral resin is dissolved in 10 parts by weight of toluene, and 5 parts by weight of 3,3', 5,5'-tetra-t-butyl-4,4'-diphenoquinone is dissolved and filtered. A coating liquid for forming a pulling layer was obtained. Using this coating liquid, an electrophotographic photosensitive member composed of an undercoat layer, a charge generation layer and a charge transport layer was prepared by the method shown in Example 1. Table 1 shows the results of the electrical characteristics evaluated using the obtained electrophotographic photosensitive member.

【0036】

Comparative example 3 The binder resin was changed to 3 parts by weight of resolphenol resin (Pryofen J-325, manufactured by Dainippon Ink and Chemicals Co., Ltd.) and dissolved in 10 parts by weight of n-butyl alcohol without using an organometallic compound. 5 parts by weight of 3,3', 5,5'-tetra-t-butyl-4,4'-diphenoquinone was dissolved and filtered to obtain a coating liquid for forming an undercoat layer. Using this coating liquid, an electrophotographic photosensitive member composed of an undercoat layer, a charge generation layer and a charge transport layer was prepared by the method shown in Example 1. Table 1 shows the results of the electrical characteristics evaluated using the obtained electrophotographic photosensitive member.

【0037】

[table 1]

<img file="JPH09197701A_D0001.tif" />【0038】

Example 2 3 parts by weight of polyvinyl butyral resin (Eslek BX-1, manufactured by Sekisui Chemical Co., Ltd.) was dissolved in 10 parts by weight of cyclohexanone, and 5 parts by weight of 2,3-dimethoxy-5-methyl-1,4-benzoquinone was further dissolved. .. 42 parts by weight of a 50% by weight toluene solution of an organic zirconium compound (cetylacetone zirconium butyrate) was mixed with the obtained solution, dissolved by stirring, and filtered to obtain a coating liquid for forming an undercoat layer. This coating liquid was applied onto an arninium substrate having a diameter of 30 mm so that the film thickness after drying was 1 μm, and dried and cured at 170 ° C. for 10 minutes to form an undercoat layer. A mixture consisting of 15 parts by weight of titanyl phthalocyanine, which is a charge generating material, 10 parts by weight of polyvinyl butyral resin (Eslek BM-S, manufactured by Sekisui Chemical Co., Ltd.), and 300 parts by weight of n-butyl alcohol was dispersed in a sand mill for 4 hours. The obtained dispersion was applied onto the undercoat layer and dried to form a charge generation layer having a film thickness of 0.2 μm. Next, 90 parts by weight of tri (p-methylphenyl) amine, which is a charge transport material, 100 parts by weight of polycartate resin (C-1400, manufactured by Teijin Chemicals Ltd.), silicone oil (KF-54, manufactured by Shinetsu Chemical Co., Ltd.) A charge transport layer coating solution consisting of 0.002 parts by weight and 870 parts by weight of tetrahydrofuran was prepared, applied on the charge generation layer, and dried to form a charge transport layer having a thickness of 24 μm, and electrophotographic photosensitive consisting of three layers was formed. The body was made. The obtained electrophotographic photosensitive member was charged to -700 V using an electrical characteristic evaluation device, and then exposed to a predetermined amount of light to measure the potential. The results are shown in Table 2.

【0039】

Examples 3 to 10 An electrophotographic photosensitive member was prepared according to the formulation shown in Example 2, except that the mixture shown in Table 2 was used instead of 2,3-dimethoxy-5-methyl-1,4-benzoquinone in Example 2. The evaluation was performed in the same manner. The results obtained are shown in Table 2.

【0040】

Comparative example 4 In Example 2, except that a coating liquid obtained by dissolving 1 part by weight of polyvinyl butyral resin in 10 parts by weight of toluene was used as the coating liquid for forming the undercoat layer to form an undercoat layer having a film thickness of 1 μm. An electrophotographic photosensitive member was prepared by forming a charge generation layer and a charge transport layer under the same conditions as in Example 2. The electrophotographic photosensitive member was evaluated in the same manner. The results obtained are shown in Table 2.

【0041】

[Table 2]

<img file="JPH09197701A_D0002.tif" />【0042】

Examples 11-19 In Example 2, electrophotographic photosensitive with the formulation shown in Example 2, except that the compounds shown in Table 3 were used in place of acetylacetone zirconium butyrate and 2,3-dimethoxy-5-methyl-1,4-benzoquinone. A body was prepared and evaluated in the same manner. The results obtained are shown in Table 3.

【0043】

[Table 3]

<img file="JPH09197701A_D0003.tif" />【0044】

Example 20 5 parts by weight of 3,3', 5,5'-tetra-t-butyl-4,4'-diphenoquinone in 10 parts by weight of tetrahydrofuran, 40 parts by weight of a 50% by weight solution of an organic zirconium compound (acetylacetone zirconium butyrate) in toluene. And 20 parts by weight of γ-aminopropyltrimethoxysilane were added and mixed, and the mixture was stirred and filtered to obtain a coating liquid for forming an undercoat layer. This coating liquid is applied by ring coating on a 30 mmφ aluminum substrate roughened by liquid phonening treatment, air-dried at room temperature for 5 minutes, and then dried and cured at 170 ° C for 10 minutes. This was carried out to form an undercoat layer having a film thickness of 0.2 μm. A mixture consisting of 15 parts by weight of hydroxygallium phthalocyanine, which is a charge generating material, 10 parts by weight of vinyl chloride-vinyl acetate copolymer resin (VMCH, manufactured by Nippon Unicar Co., Ltd.), and 300 parts by weight of n-butyl alcohol was prepared in a sand mill for 4 hours. Distributed processing was performed. The obtained dispersion was immersed and coated on the undercoat layer and dried to form a charge generation layer having a film thickness of 0.2 μm. Next, N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine 4 parts by weight and bisphenol Z polycarbonate resin (molecular weight 40,000) ) Using a solution obtained by dissolving 80 parts by weight of chlorobenzene by adding 6 parts by weight, a charge transport layer having a thickness of 20 μm is formed by coating and drying to prepare an electrophotographic photosensitive member consisting of three layers. did. The obtained electrophotographic photosensitive member was charged to -700 V using an electrical characteristic evaluation device, and then exposed to a predetermined amount of light to measure the potential. The results are shown in Table 4.

【0045】

[Table 4]

<img file="JPH09197701A_D0004.tif" />【0046】

[Effect of the invention]

The electrophotographic photosensitive member of the present invention is a photoconductor in which a charge generating layer and a charge transporting layer are sequentially laminated on a conductive support, and at least an organometallic compound and a silane cup are formed between the conductive support and the charge generating layer. Since it has a cured film formed of either or both of the phosphorus agents, an electron-accepting compound, and a binder resin as the undercoat layer, the undercoat layer does not elute when the upper layer is applied, and stable electrical characteristics are maintained. It has. In addition, by using an organometallic compound or a silane coupling agent in combination with an electron-accepting compound, excellent electrophotographic properties such as high photoattenuation and low residual potential can be obtained as compared with the case where they are used alone. It has excellent sensitivity, image quality, and repeatability.