JP2002311608A - Electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor excellent in surface lubricity, wear resistance and electrical response of a photosensitive layer and using a binder resin excellent in solubility in a solvent when a coating liquid for forming the photosensitive layer on an electrically conductive substrate is prepared and giving a coating liquid excellent in storage stability. SOLUTION: The electrophotographic photoreceptor is obtained by forming a photosensitive layer on an electrically conductive substrate and the binder resin in the photosensitive layer is a polyarylate resin having constitutional units of formula (I) as principal repeating units and containing <10 mol% constitutional units of formula (II).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member having a photosensitive layer formed on a conductive support, and more particularly, to a surface slip, abrasion resistance, and electrical response as a photosensitive layer. The present invention relates to an electrophotographic photoreceptor using a binder resin, which is excellent in solvent solubility when preparing a coating solution for forming the photosensitive layer on a conductive support and has excellent storage stability of the coating solution.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic image forming method, a photosensitive member having a photosensitive layer formed on a conductive support is uniformly charged and then exposed to light, and the charge of the exposed portion is changed. To form an electrostatic latent image, and the charged electrostatic toner is made visible by developing a latent image by attaching charged toner to an unexposed portion. A method of transferring the image to a transfer material and fixing the visible image to the transfer material by heating, pressurizing, or the like is widely used in copying machines, printers, and the like because a high-quality image can be obtained immediately.

As the photoconductive material of the photoreceptor, conventional inorganic materials such as selenium, arsenic-selenium alloy, cadmium sulfide, and zinc oxide have recently been superior in safety and film formability. Due to their properties, they are being replaced by organic photoconductive materials. On the other hand, the photosensitive layer of the photoreceptor made of an organic photoconductive material includes a single layer type in which a photoconductive substance is dispersed in a binder resin, and a charge generation in which a charge generation substance is dispersed in a binder resin. There is a laminated type consisting of two layers of a layer and a charge transporting layer in which a charge transporting substance is dispersed in a binder resin, and the latter laminated type can provide a highly safe photoreceptor with a wide selection of materials, The use of a charge generating substance and a charge transporting substance makes it possible to obtain a highly sensitive photoreceptor, and the advantages such as a high productivity are utilized.

Since the electrophotographic photosensitive member is repeatedly used in an electrophotographic process, that is, in a cycle of charging, exposure, development, transfer, cleaning, charge elimination, and the like, for example, it is rubbed with a cleaning blade, a magnetic brush, or the like. And
The photosensitive layer is worn out due to contact with the developer, transfer material, etc.
Abrasion undergo mechanical degradation of delamination or the like, by strongly oxidizing ozone or NO _X or the like generated from the corona charger is generally used as a charger, also generated by the image exposure carriers ( Current) flows, or is chemically and electrically deteriorated by static elimination light, external light, and the like. When the photosensitive layer is of the stacked type, the deterioration is caused by electric charge The transport layer, the binder resin in the layer, these mechanical degradation, and, chemical,
It will endure durability against electrical degradation.

[0005] Also, due to the growing demand for high-speed printing in recent years,
There is a demand for a material that is compatible with a higher speed electrophotographic process, and the photosensitive layer is required to have electrical responsiveness due to the shortening of the above-described electrophotographic process cycle. It is known that although it is mainly controlled by the charge transport material, it greatly varies depending on the binder resin.

Further, each of the layers constituting the electrophotographic photoreceptor includes:
Since the binder resin is formed by applying a coating solution on the surface of the support and drying the coating solution, the binder resin is also required to have solubility in a solvent when the coating solution is prepared and storage stability of the coating solution.

[0007] In order to meet these required performances, as binder resins, conventionally, thermoplastic resins such as polymethyl methacrylate, polystyrene, polyvinyl chloride, polycarbonate, polyester, polysulfone, phenoxy resins, epoxy resins, silicone resins Thermosetting resins such as are used, in which, since polycarbonate can express relatively excellent performance, is often used,
As a binder resin for the photosensitive layer of the electrophotographic photosensitive member, for example, 1,1-bis (4′-hydroxyphenyl) -1-
Phenylethane [bisphenol P] type polycarbonate (JP-A-50-98332), 1,1-
Bis (4'-hydroxyphenyl) cyclohexane [bisphenol Z] type polycarbonate (JP-A-5
No. 9-71057), copolymerization of 1,1-bis (4′-hydroxyphenyl) -1-phenylethane [bisphenol P] and 2,2-bis (4′-hydroxyphenyl) propane [bisphenol A] There are known polycarbonates of the type (JP-A-59-184251) and copolymerization-type polycarbonates containing a bis (4-hydroxyphenyl) ketone (JP-A-5-21478).

However, the electrophotographic photoreceptor using polycarbonate as a binder resin for the photosensitive layer is not always sufficient in abrasion resistance and abrasion resistance. On the other hand, the electrophotographic photoreceptor is a polyester having a diol component of diphenol. It has been proposed to use an arylate resin. For example, JP-A-56-135844 discloses a polyarylate resin using bisphenol A as a diol component, and JP-A-3-6567 discloses a diol component. Polyarylate resin using bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F] and bisphenol A
0-288845 and JP-A-10-288846
In the publication, 2,2-bis (3 ′
-Methyl-4'-hydroxyphenyl) propane [bisphenol C] or 2,2-bis (3 ', 5'-
An electrophotographic photoreceptor using a polyarylate resin using dimethyl-4'-hydroxyphenyl) propane [tetramethylbisphenol A] as a binder resin is disclosed.

An electrophotographic photoreceptor using these conventionally known polyarylate resins as a binder resin for a photosensitive layer is disclosed in JP-A-56-135844.
Although the sensitivity and the abrasion resistance are improved, the storage stability of the coating solution is inferior. In the resin disclosed in JP-A-3-6567, although the mechanical properties are improved, the sensitivity and the electric resistance are improved. Sufficient performance cannot be obtained in terms of responsiveness, and Japanese Patent Application Laid-Open Nos. Hei 10-288845 and
In the resin disclosed in 0-288846, mechanical properties,
Although improvements in solvent solubility and storage stability of the coating solution were observed, electrical responsiveness was insufficient.

Therefore, any resin conventionally known as a binder resin for a photosensitive layer of an electrophotographic photosensitive member can be used to smoothly operate even by repeated contact with a transfer material or the like, and to improve the surface slipperiness. Abrasion resistance, and electrical responsiveness such as easiness of charging and easiness of static elimination, and further, solvent solubility in forming a coating solution in forming a photosensitive layer on a conductive support, and its coating It is not possible to satisfy both of the storage stability of the liquid at the same time and a binder resin capable of simultaneously satisfying these properties and an electrophotographic photoreceptor using the same are required.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art. Therefore, the present invention provides a photosensitive layer having excellent surface slipperiness, abrasion resistance, and electrical response. And to provide an electrophotographic photoreceptor using a binder resin which is excellent in solvent solubility during preparation of a coating solution in forming the photosensitive layer on a conductive support and storage stability of the coating solution. Aim.

[0012]

The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that the above object can be achieved by using a specific copolymer polyarylate resin as a binder resin in a photosensitive layer. In other words, the present invention is an electrophotographic photosensitive member having a photosensitive layer formed on a conductive support, wherein the binder resin in the photosensitive layer is represented by the following formula (I): The structural unit represented is the main repeating unit, and the following general formula
An electrophotographic photoreceptor, which is a polyarylate resin containing the structural unit represented by (II) in a proportion of less than 10 mol%.

[0013]

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[Formula (I) represents a structural unit in which the phenylene group at the right end is a p-phenylene group and a structural unit in which the m-phenylene group is the m-phenylene group. Is less than 30 mol%. ]

[0015]

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[In the formula (II), A represents an arylene group which may have a substituent, n is 0 or 1, and when n is 1, X represents a single bond or a substituent. An alkylene group which may be substituted (however, when it is a methylene group, the structure including A is not the same as the structure in the formula (I)); a cycloalkylene group which may have a substituent; Represents a phenylene dimethylene group, an ether group, a carbonyl group, a thioether group, a sulfinyl group, or a sulfonyl group which may have a benzene ring, and the benzene ring bonded to X may have a substituent. Formula (II) represents a structural unit in which the phenylene group at the right end is a p-phenylene group and a structural unit in which the right-hand phenylene group is an m-phenylene group.
The proportion of structural units that are phenylene groups is less than 30 mol%; ]

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION In the electrophotographic photoreceptor of the present invention, a binder resin of a photosensitive layer formed on a conductive support has a constitutional unit represented by the above formula (I) as a main repeating unit,
And 10 mol% of the structural unit represented by the general formula (II).
It is essential that the resin is a polyarylate resin containing the resin in a proportion of less than 10%, so that the object of the present invention can be achieved.

In the polyarylate resin of the present invention, the structural unit of the above formula (I) constituting the main repeating unit is bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol] as a diol component F] and an esterification reaction of terephthalic acid and isophthalic acid as dicarboxylic acid components, and the structural unit of the general formula (II) includes an aromatic diol as a diol component and a dicarboxylic acid component. Based on an esterification reaction with terephthalic acid and isophthalic acid.

Here, in the general formula (II), examples of the arylene group of A include a phenylene group and a naphthylene group, among which a phenylene group is preferred.
Further, it is preferable that n is 1, and when n is 1, the alkylene group of X has 1 to 5 carbon atoms, and the cycloalkylene group has 5 to 8 carbon atoms. X is preferably a single bond, an alkylene group which may have a substituent, a cycloalkylene group which may have a substituent, a phenylene dimethylene group which may have a substituent, or an ether. Among the group, carbonyl group, thioether group, sulfinyl group, and sulfonyl group, a single bond or an alkylene group which may have a substituent is preferable, and a methylene group which may have a substituent is particularly preferable. .

In the above general formula (II), examples of the substituent in the arylene group of A and the alkylene group, cycloalkylene group and phenylenedimethylene group of X include alkyl groups having 1 to 10 carbon atoms. And a halogenated alkyl group thereof, an alkoxy group having 1 to 10 carbon atoms, a phenyl group, a halogen atom and the like. Also, X
The same can be mentioned as the substituent on the benzene ring bonded to.

In the present invention, the preferred methylene group as X is preferably any of an unsubstituted methylene group, a monoalkyl-substituted methylene group, and a dialkyl-substituted methylene group, and a dialkyl-substituted methylene group is preferred. Particularly preferred is a methyl group as the substituted alkyl group. It is particularly preferable that the benzene ring in the arylene group of A and the phenylene group bonded to X has no substituent or has a methyl group as a substituent at the 2-, 3-, 5-, or 6-position. preferable. The general formula
(II), the A 1, n is preferably, when a methylene group of the X is preferably, A also including the basic structure _{[-A-CH 2 -C 6 H 4} - ] in formula (I) It is necessary that the structure is not the same as that of the formula (I), and if the structure is the same as that of the formula (I), the effect of the present invention cannot be achieved.

Examples of the aromatic diol as a diol component constituting the structural unit of the general formula (II) containing A and X include, for example, pyrocatechol, resorcinol, hydroquinone, xylylene glycol and the like. Dihydroxybenzenes, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-
Dihydroxynaphthalenes such as dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, bis (4-hydroxyphenyl), bis (3-methyl- 4-hydroxyphenyl), bis (3-t-butyl-4-hydroxyphenyl), bis (3,5-dimethyl-4-hydroxyphenyl), bis (3,5-di-t-butyl-4-hydroxyphenyl) ), Bis (2,3,5-trimethyl-4-hydroxyphenyl), bis (2,3,5,6-tetramethyl-4-hydroxyphenyl) and the like, Phenyl) methane,
Bis (4-hydroxyphenyl) methane [bisphenol F], 2-hydroxyphenyl-4-hydroxyphenyl-methane, bis (3-methyl-4-hydroxyphenyl) methane [dimethylbisphenol F], bis (2,3,5 -Trimethyl-4-hydroxyphenyl)
Methane, bis (2,3,5,6-tetramethyl-4-hydroxyphenyl) methane, bis (3-phenyl-4-
Hydroxyphenyl) methane, 1,1-bis (4′-hydroxyphenyl) ethane [bisphenol E],
1-bis (3'-methyl-4'-hydroxyphenyl)
Ethane, 1,1-bis (3 ′, 5′-dimethyl-4′-
Hydroxyphenyl) ethane, 1,1-bis (3 ′,
6'-dimethyl-4'-hydroxyphenyl) ethane,
1,1-bis (2 ′, 3 ′, 6′-trimethyl-4′-
Hydroxyphenyl) ethane, 1,1-bis (2 ′,
3 ′, 5 ′, 6′-tetramethyl-4′-hydroxyphenyl) ethane, 1,1-bis (3′-phenyl-4 ′)
-Hydroxyphenyl) ethane, 1,1-bis (4′-
Hydroxyphenyl) propane, 1,1-bis (3′-
Phenyl-4'-hydroxyphenyl) propane, 2,
2-bis (4'-hydroxyphenyl) propane [bisphenol A], 2,2-bis (3'-methyl-4'-
Hydroxyphenyl) propane [bisphenol C],
2,2-bis (3′-ethyl-4′-hydroxyphenyl) propane, 2,2-bis (3′-i-propyl-)
4'-hydroxyphenyl) propane, 2,2-bis (3'-s-butyl-4'-hydroxyphenyl) propane, 2,2-bis (3 ', 5'-dimethyl-4'-hydroxyphenyl) propane [Tetramethylbisphenol A], 2,2-bis (2 ', 3', 5'-trimethyl-4'-hydroxyphenyl) propane, 2,2-bis (2 ', 3', 5 ', 6'- Tetramethyl-4′-hydroxyphenyl) propane, 2,2-bis (3′-phenyl-4′-hydroxyphenyl) propane [bisphenol Q], 2,2-bis (4′-hydroxyphenyl) butane, 2, 2-bis (4'-hydroxyphenyl) -3-methylbutane, 2,2-bis (4'-hydroxyphenyl) pentane, 2,2-bis (4'-hydroxyphenyl) -4-methylpentane, 2,2 -Screw 4'-hydroxyphenyl) hexane, bis such phenolphthalein (hydroxyphenyl) alkanes,
Bis (4-hydroxyphenyl) phenylmethane, bis (2,3,5-trimethyl-4-hydroxyphenyl)
Phenylmethane, bis (4-hydroxyphenyl) diphenylmethane, 1,1-bis (4′-hydroxyphenyl) -1-phenylethane [bisphenol P], 1,
1-bis (2 ′, 3 ′, 5′-trimethyl-4′-hydroxyphenyl) -1-phenylethane, 1,1-bis (4′-hydroxyphenyl) -1-phenylpropane, 2,2-bis (4′-hydroxyphenyl) -1,
Bis (hydroxyphenyl) phenylalkanes such as 3-diphenylpropane, 1,1-bis (4′-hydroxyphenyl) cyclopentane, 1,1-bis (4′-
Hydroxyphenyl) cyclohexane [bisphenol Z], 1,1-bis (2 ′, 3 ′, 5′-trimethyl-
Bis (hydroxyphenyl) cycloalkanes such as 4′-hydroxyphenyl) cyclohexane, bis (4 ′
-Hydroxyphenyl) -1,4-phenylenedimethylene, bis (2 ', 6'-dimethyl-4'-hydroxyphenyl) -1,4-phenylenedimethylene, bis (2', 3 ', 6'-trimethyl -4'-hydroxyphenyl) -1,4-phenylenedimethylene, bis (2 ', 6'-dimethyl-4'-hydroxyphenyl)
-1,4-phenylenebis (α-methylethylidene),
Bis (2 ′, 3 ′, 6′-trimethyl-4′-hydroxyphenyl) -1,4-phenylenebis (α-methylethylidene), bis (2 ′, 3 ′, 6′-trimethyl-
4′-hydroxyphenyl) -1,3-phenylenebis (α-methylethylidene), bis (4′-hydroxyphenyl) -1,4-phenylenebis (α-methylvinylidene), bis (2′-methyl-4) Bis (hydroxyphenyl) phenylenediethylenes such as' -hydroxyphenyl) -1,4-phenylenebis (α-methylvinylidene), bis (4-hydroxyphenyl) ether [bisphenol O], bis (3,5-dimethyl Bis (hydroxyphenyl) ethers such as -4-hydroxyphenyl) ether, bis (hydroxyphenyl) ketones such as bis (4-hydroxyphenyl) ketone and bis (3,5-dimethyl-4-hydroxyphenyl) ketone;
Bis (hydroxyphenyl) sulfides such as bis (4-hydroxyphenyl) sulfide and bis (3,5-dimethyl-4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfoxide, bis (3,5-dimethyl- Bis (hydroxyphenyl) sulfoxides such as 4-hydroxyphenyl) sulfoxide; bis (hydroxyphenyl) such as bis (4-hydroxyphenyl) sulfone [bisphenol S] and bis (3,5-dimethyl-4-hydroxyphenyl) sulfone
Sulfones and the like.

In the above formula (I) and the above formula (II), a structural unit in which the rightmost phenylene group is a p-phenylene group derived from terephthalic acid as a dicarboxylic acid component,
M- derived from isophthalic acid as a dicarboxylic acid component
A phenylene group, and the ratio of the m-phenylene group to the total of both structural units is less than 30 mol%, preferably 1 to 9 mol%, Particularly preferred is 1 to 7 mol%. When the proportion of the structural unit that is an m-phenylene group is greater than or equal to the above range, the electrical responsiveness and the like of the photosensitive layer of the electrophotographic photosensitive member will be poor.
The storage stability of the coating solution in forming the photosensitive layer on a conductive support tends to be poor.

The aromatic dicarboxylic acid as a dicarboxylic acid component constituting these structural units includes derivatives such as halides such as terephthalic acid and isophthalic acid chloride.

The polyarylate resin as the binder resin in the present invention contains the structural unit represented by the above formula (I) as a main repeating unit, and contains 10 mol% of the structural unit represented by the above general formula (II). Less than
It is preferable to contain the structural unit represented by the general formula (II) at a ratio of 1 to 9 mol%, particularly preferably 1 to 7 mol%. When the proportion of the structural unit represented by the general formula (II) is greater than or equal to the above range, the abrasion resistance and the electrical responsiveness of the photosensitive layer of the electrophotographic photoreceptor will be inferior. In forming the photosensitive layer on the conductive support, the solvent solubility in preparing the coating solution and the storage stability of the coating solution tend to be poor.

In the present invention, the polyarylate resin is prepared by subjecting the aromatic diol as a diol component and the aromatic dicarboxylic acid as a dicarboxylic acid component to known polymerization methods such as an interfacial polymerization method, a melt polymerization method, and a solution polymerization method. It is produced by a polycondensation reaction using a synthetic method. For example,
In the production by the interfacial polymerization method, an aqueous alkali solution of an aromatic diol is mixed with a halogenated hydrocarbon solution of an aromatic dicarboxylic acid, and in the presence or absence of a quaternary ammonium salt or a quaternary phosphonium salt as a catalyst, 0-40 ° C
After the reaction, the aqueous phase and the organic phase are separated, and the polymer dissolved in the organic phase is separated by a known method, followed by washing and drying.

Here, examples of the alkali component used in the aqueous alkali diol solution of an aromatic diol include hydroxides of alkali metals such as sodium hydroxide and potassium hydroxide, and halogens of an aromatic dicarboxylic acid. Examples of the halogenated hydrocarbon solvent used in the halogenated hydrocarbon solution include dichloromethane, trichloromethane,
2-dichloroethane, trichloroethane, tetrachloroethane, dichlorobenzene and the like can be mentioned. Examples of the quaternary ammonium salt or quaternary phosphonium salt as a catalyst include, for example, salts of tertiary alkylamines such as tributylamine and trioctylamine with hydrochloric acid, bromate and iodic acid, benzyltrimethylammonium chloride, benzyltriethyl and the like. Ammonium chloride, benzyltributylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium bromide, trioctylmethylammonium chloride, N-laurylpyridinium chloride, laurylpicolinium chloride,
Examples include tetrabutylphosphonium bromide and triethyloctadecylphosphonium bromide.

In the polycondensation reaction, phenol, cresol, ethylphenol, propylphenol, t-butylphenol, dimethylphenol, methyl-t-butylphenol, trimethylphenol, tetramethylphenol, dimethyl-t-phenol are used as molecular weight regulators. Monofunctional phenols such as butylphenol, dimethyl-acetylphenol, and phenylphenol, acetic chloride, butyric chloride, octyl chloride, benzoyl chloride, benzenesulfonyl chloride, benzenesulfinyl chloride, benzenephosphonyl chloride, and substituted products thereof Monofunctional acid halides and the like, among which at least the 2-position and 6-position
Phenols having a methyl group at the 2-position, specifically, for example, 2,6-dimethylphenol, 2,3,6-trimethylphenol, 2,4,6-trimethylphenol,
2,3,4,6-tetramethylphenol, 2,6-dimethyl-4-t-butylphenol, 2,6-dimethyl-4-nonylphenol, 2,6-dimethyl-4-acetylphenol, α-tocopherol and the like Is preferred, and 2,3,6-trimethylphenol is particularly preferred.

The polyarylate resin of the present invention has a viscosity average molecular weight of 10,000 to 300,000.
Is preferred, more preferably from 15,000 to 100,000, and particularly preferably from 20,000 to 50,000. If the viscosity average molecular weight is less than the above range, the photosensitive layer of the electrophotographic photoreceptor tends to have poor mechanical properties such as abrasion resistance, whereas if the viscosity average molecular weight exceeds the above range, the photosensitive layer is formed on a conductive support. The applicability of the coating solution tends to be poor.

As the binder resin for the photosensitive layer in the present invention, in addition to the polyarylate resin, for example, polyacrylic acid esters, polymethacrylic acid esters, polyvinyl acetate, and the like may be used as long as the effects of the present invention are not impaired. Polyvinyl acetoacetal, polyvinyl propional, polyvinyl butyral, cellulose ester, cellulose ether, polyester, polycarbonate, phenoxy resin, epoxy resin, urethane resin and the like may be used in combination.

The conductive support in the electrophotographic photosensitive member of the present invention is not particularly limited.
Aluminum, aluminum alloy, stainless steel, copper,
Metal material such as nickel, metal, carbon, resin material added conductivity by adding conductive powder such as tin oxide, and
A resin, glass, paper, or the like in which a conductive material such as aluminum, nickel, and ITO (indium oxide-tin oxide) is deposited or applied on the surface thereof is mainly used. Further, a conductive material having an appropriate resistance value may be applied on a conductive support made of a metal material for controlling conductivity, surface characteristics and the like and covering defects. Examples of the form include those conventionally used, such as a drum, a sheet, or a belt. When a metal material such as aluminum or an aluminum alloy is used as the conductive support, the surface thereof may be subjected to anodic oxidation treatment, conversion coating treatment, or the like, or may be subjected to sealing treatment when subjected to anodic oxidation treatment. Is preferred. The support surface may be smooth, or may be roughened by a cutting or polishing treatment, and further roughened by adding particles of an appropriate particle size to the support material. It may be something.

The photosensitive layer formed on the conductive support may be a single layer type in which a charge generating substance and a charge transporting substance are dispersed in a binder resin, or a single layer type in which the charge generating substance is dispersed in a binder resin. And a charge generation layer dispersed in a binder resin and a charge transport layer dispersed in a binder resin.

The charge generating substance is not particularly limited. For example, selenium and its alloys, cadmium sulfide, other inorganic photoconductive materials, phthalocyanine pigments, azo pigments, quinacridone pigments, indigo pigments, perylene pigments Various photoconductive materials such as organic photoconductive materials such as organic pigments such as polycyclic quinone pigments, anthantrone pigments and benzimidazole pigments are used. Among them, organic pigments are preferable, and phthalocyanine pigments and azo pigments are particularly preferable.

Examples of the phthalocyanine pigment include metals such as metal-free phthalocyanine, copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, and germanium, or oxides, halides, hydroxides, and alkoxides thereof. Phthalocyanine. In particular, X type, τ type metal-free phthalocyanine, A type, B type, D type
Preference is given to types such as titanyl phthalocyanine, vanadyl phthalocyanine, chloroindium phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine and the like. In addition, among the crystal forms of titanyl phthalocyanine, A type and B type are described in W.S. Heller et al. Show them as phase I and phase II, respectively (Zei
t. Kristallogr. 159 (1982) 17
3), Type A is what is known as a stable type. D
The type is a crystal type characterized by showing a clear peak at a diffraction angle (2θ ± 0.2 °) of 27.3 ° in powder X-ray diffraction using CuKα ray. The phthalocyanine pigments may be used singly or in a mixed state. The mixed state may be an acid paste in a manufacturing / processing step such as synthesis, pigmentation, or crystallization, even if they are mixed. A mixed state may be produced by a treatment, a grinding treatment, a solvent treatment or the like.

In the present invention, the amount ratio of the binder resin to the charge generating substance in the photosensitive layer is preferably 30 to 500 parts by weight of the charge generating substance with respect to 100 parts by weight of the binder resin.

The charge transporting substance is not particularly limited either. For example, aromatic nitro compounds such as 2,4,7-trinitrofluorene, cyano compounds such as tetracyanoquinodimethane, diphenoquinone, etc. Electron-withdrawing substances such as quinones, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, oxadiazole derivatives, pyrazoline derivatives, thiadiazole derivatives and other heterocyclic compounds, aniline derivatives, hydrazone derivatives, aromatic or heterocyclic Ring amine derivatives, stilbene derivatives, butadiene derivatives, enamine compounds, compounds in which a plurality of these derivatives are bonded, and electron-donating substances such as polymers having a group containing these derivatives in a main chain or a side chain. Can be
Among them, carbazole derivatives, hydrazone derivatives, aromatic or heterocyclic amine derivatives, stilbene derivatives, and butadiene derivatives, and compounds in which a plurality of these derivatives are bonded are preferable, and aromatic or heterocyclic amine derivatives, stilbene derivatives, and A compound in which a plurality of butadiene derivatives are bonded is particularly preferable, and specific examples thereof include a compound represented by the following general formula (III).

[0037]

Embedded image

[In the formula (III), Z is a single bond or divalent
Indicates the base, Y¹, Y^Two, Y^Three, And Y^FourAre independent
An optionally substituted arylene group, or substituted
A divalent heterocyclic group which may have a group;¹as well as
n^TwoIs each independently 0 or 1, and n¹And n^TwoIs 0
When, Y^FiveAnd Y⁶Each independently has a substituent
Alkyl group which may be present, ant which may have a substituent
Or a monovalent heterocyclic group which may have a substituent
And n¹And n^TwoWhen is 1, Y^FiveAnd Y ⁶Are each
Independently, an alkylene group which may have a substituent,
Arylene group which may have a substituent, or
An optionally substituted divalent heterocyclic group;¹, R^Two, R
^Three, R^Four, R^Five, R⁶, R⁷, And R⁸Are independent
An alkyl group which may have a substituent,
Optionally having a cycloalkyl group, a substituent
Aryl group, monovalent compound which may have a substituent
A ring group or a hydrogen atom, m¹, M^Two, M^Three,as well as
m^FourAre each independently an integer from 0 to 4. ]

In the formula (III), examples of the divalent organic group represented by Z include an alkylene group which may have a substituent and a cycloalkylene group which may have a substituent. Or an arylene group which may have a substituent, and those groups bonded with an oxygen atom or a sulfur atom, for example, [-O-Z'-O-], [-Z'-0
-Z'-], [-SZ'-S-], [-Z'-S-
Z'-] (where, Z 'is an alkylene group, a cycloalkylene group, or an arylene group) and the like.

The alkylene group represented by Z has 1 carbon atom.
To 6, preferably a methylene group or an ethylene group, and the cycloalkylene group preferably has 5 to 8 carbon atoms, and a cyclopentylene group or a cyclohexylene group is preferred. Particularly preferred, and
Examples of the arylene group include a phenylene group, a naphthylene group, an anthrylene group and the like, and a phenylene group is particularly preferred. Among the above, in the present invention, Z is particularly preferably a single bond.

The substituent in the alkylene group, cycloalkylene group and arylene group represented by Z is, for example, an alkyl group having usually 1 to 6 carbon atoms and usually having 5 carbon atoms.
An alkenyl group having 1 to 6 carbon atoms such as a cycloalkyl group, a vinyl group, an allyl group, an aryl group such as a phenyl group, a naphthyl group and an anthryl group, a hydroxyl group, a nitro group,
Examples include a cyano group and a halogen atom.

In the general formula (III), Y ^{1 to} Y
⁴ is each independently an arylene group which may have a substituent or a divalent heterocyclic group which may have a substituent, and when n ¹ and n ² are 0, Y ⁵ And Y ⁶ are each independently an alkyl group optionally having a substituent, an aryl group optionally having a substituent, or a monovalent heterocyclic group optionally having a substituent. And when n ¹ and n ² are 1, Y ⁵ and Y ⁶ are each independently an alkylene group which may have a substituent, an arylene group which may have a substituent, or a substituent Wherein the alkyl group has 1 carbon atom.
To 6, and particularly preferably a methyl group or an ethyl group, and the alkylene group preferably has 1 to 6 carbon atoms, and is preferably a methylene group or an ethylene group. Particularly preferred examples of the aryl group include, for example, a phenyl group, a naphthyl group, and an anthryl group.A phenyl group is particularly preferred. And a phenylene group is particularly preferable. As the monovalent heterocyclic group, a heterocyclic group having an aromatic property is preferable, and examples thereof include a furyl group, a thienyl group, and a pyridyl group. As the valent heterocyclic group, an aromatic heterocyclic group is preferable, and examples thereof include a furylene group, a thienylene group, and a pyridylene group. In the above, in the present invention, Y ¹ , Y ² ,
Y ³ and Y ⁴ are particularly preferably phenylene groups,
n ¹ and n ² are 0, and Y ⁵ and Y ⁶ are particularly preferably phenyl groups.

In the above general formula (III), R ^{1 to} R
It is preferably from 1 to 8 carbon atoms as ⁸ alkyl group, particularly preferably that has 1 to 6 carbon atoms, also, it is preferably the cycloalkyl group is a 5 to 8 carbon atoms, A cyclopentyl group or a cyclohexyl group is particularly preferable, and examples of the aryl group include a phenyl group, a naphthyl group, and an anthryl group. A phenyl group is particularly preferable, and a monovalent heterocyclic group is aromatic. A heterocyclic group having a group property is preferable, for example, a furyl group,
Examples thereof include a thienyl group and a pyridyl group. In the above,
In the present invention, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R
^{As 6} , ⁶ , R ⁷ and R ⁸ , a methyl group or a phenyl group is particularly preferred.

Incidentally, arylene groups of Y ^{1 to} Y ⁴ , divalent heterocyclic groups, alkyl groups and aryl groups of Y ⁵ and Y ⁶ ,
A monovalent heterocyclic group, an alkylene group, an arylene group, and 2
Examples of the substituent on the divalent heterocyclic group, and the alkyl group, cycloalkyl group, aryl group, and monovalent heterocyclic group represented by R ^{1 to} R ⁸ include, for example, an alkyl group having usually 1 to 6 carbon atoms, A cycloalkyl group having usually 5 to 8 carbon atoms, an alkoxy group having usually 1 to 6 carbon atoms, an acyl group such as an alkenyl group usually having 1 to 6 carbon atoms such as a vinyl group and an allyl group, an acetyl group and a benzoyl group. Phenyl group, naphthyl group, aryloxy group such as anthryl group, phenoxy group, aryloxy group such as naphthoxy group, methylthio group, alkylthio group such as ethylthio group, phenylthio group, arylthio group such as naphthylthio group, dimethylamino group, diethylamino Substituted amino such as group, diallylamino group, diphenylamino group, dinaphthylamino group, dipyridylamino group, dithienylamino group , A hydroxyl group, a nitro group, and cyano group, and a halogen atom and the like. Among the above, in the present invention, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an alkylthio group, an arylthio group, a dialkylamino group, a hydroxyl group, a cyano group, and a halogen atom are preferable, and a methyl group or a phenyl group Is particularly preferred.

In the present invention, the amount ratio of the binder resin to the charge transporting material in the photosensitive layer is preferably 30 to 200 parts by weight, more preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin. Is more preferable.

In the present invention, if necessary, methyl violet, brilliant green,
Dyes such as triphenylmethane dyes such as crystal violet, thiazine dyes such as methylene blue, quinone dyes such as quinizarin, and chloranil;
Dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 1-chloro-5-nitroanthraquinone, 2-
Chloroanthraquinone, quinones such as phenanthrenequinone, aldehydes such as 4-nitrobenzaldehyde,
9-benzoylanthracene, indandione, 3,5
Ketones such as dinitrobenzophenone, 3,3 ′, 5,5′-tetranitrobenbuphenone, 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, tetracyanoethylene, Cyano compounds such as terephthalalmalononitrile, 9-anthrylmethylidenemalononitrile, 4-nitrobenzalmalononitrile, 4- (p-nitrobenzoyloxy) benzalmalononitrile, 3-benzalphthalide, 3- (α- Phthalides such as cyano-p-nitrobenzal) phthalide and 3- (α-cyano-p-nitrobenzal) -4,5,6,7-tetrachlorophthalide; condensed polycyclic aromatic compounds such as perylene; Acid, acid anhydrides such as 4-chloronaphthalic anhydride, metal salts or metal complexes of substituted or unsubstituted salicylic acid, aromatic May be electron-withdrawing compounds such as metal salts or metal complexes of carboxylic acids have been added, further, for example, phthalic acid esters, phosphoric acid esters, chlorinated fatty acid esters, chlorinated paraffin, epoxy compounds,
Plasticizers such as methylnaphthalene, and additives such as antioxidants, heat stabilizers, ultraviolet absorbers, antistatic agents, lubricants, mold release agents, flame retardants, and leveling agents may be added.

An undercoat layer may be provided between the conductive support and the photosensitive layer. The undercoat layer may be made of aluminum oxide, silicon oxide, titanium oxide, iron oxide, zinc oxide. Fine particles such as metal oxides such as zirconium oxide, calcium titanate, strontium titanate, metal titanates such as barium titanate, nitrides such as titanium nitride and silicon nitride, titanium carbide and carbides such as silicon carbide, Usually, it is dispersed in a binder resin such as polyacrylic acid, polyvinyl alcohol, polyvinyl butyral, polyvinyl pyrrolidone, polyurethane resin, polyamide resin, cellulose, casein, epoxy resin, phenol resin, and melamine resin, and the fine particles and the binder resin are dispersed. On the support surface as a coating solution in which is dissolved or dispersed in a solvent or a dispersion medium. And cloth, by drying, preferably particle concentration of 10 to 80 wt%, preferably 0.05 to 20 m, more preferably 0.1 to 10
It is formed with a thickness of μm.

In this case, as the fine particles, titanium oxide or aluminum oxide is preferable, and titanium oxide is particularly preferable. The surface of titanium oxide is tin oxide,
It may be treated with an inorganic substance such as aluminum oxide, antimony oxide, zirconium oxide, or silicon oxide, or an organic substance such as stearic acid, polyol, or silicone. The fine particles preferably have an average primary particle diameter of 10 to 100 nm.

The polyarylate resin as a binder resin for the photosensitive layer in the present invention is used for the photosensitive layer in the case of a single layer type, and is used for either the charge generation layer or the charge transport layer in the case of the multilayer type. However, it is preferably used at least for the layer located on the surface side or the charge transport layer.

Further, on the surface of the photoreceptor having the above-mentioned various laminated structures, a surface protective layer containing the above-mentioned binder resin or the like as a main component is preferably 0.01 to 20 μm, more preferably 0.1 to 20 μm. It may be provided with a thickness of 10 μm.

In the present invention, when the photosensitive layer is formed of a single-layer type, the charge generating substance, the charge transporting substance, and the polyarylate resin, or, if necessary, other binder resins or additives. Agent or the like, as a coating solution obtained by dissolving or dispersing in a solvent or a dispersion medium, in the case of a laminated type, the charge generation substance, and the polyarylate resin or other binder resin or additives, etc., in a solvent or a dispersion medium. As a coating solution dissolved or dispersed, or, as the coating solution in which the charge transport material, and the polyarylate resin or other binder resin or additives and the like as necessary, are dissolved or dispersed in a solvent or a dispersion medium, On the support, or on the undercoat layer formed thereon, as a dry film thickness, in the case of a single layer type, preferably 5 to 50 μm,
More preferably, it is 10 to 45 μm, and in the case of a laminated type, the charge generation layer is preferably 0.1 to 1 μm, more preferably 0.1 to 1 μm.
15 to 0.6 μm, the charge transport layer is preferably 5 to 50 μm.
m, more preferably 10 to 45 μm, and drying.

The solvent or dispersion medium used for preparing the coating solution at this time is, for example, methyl alcohol,
Alcohols such as ethyl alcohol and propyl alcohol, methyl formate, ethyl acetate, methyl cellosolve, methyl cellosolve acetate, tetrahydrofuran, 1,4
Ethers such as dioxane, ethyl acetate, esters such as butyl acetate, acetone, methyl ethyl ketone, ketones such as cyclohexanone, benzene, toluene, aromatic hydrocarbons such as xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,
Chlorinated hydrocarbons such as 1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene, n-butylamine, isopropanolamine, diethylamine, triethanolamine, ethylenediamine, triethylenediamine Nitrogen-containing compounds such as, acetonitrile,
Non-protonic polar solvents such as N-methylpyrrolidone, N, N-dimethylformamide, dimethylsulfoxide and the like are used, and these are used alone or in combination of two or more.

Examples of the coating method at this time include a dipping method, a spray method, a bar coater method, a blade method, a roll coater method, a wire bar method, a knife coater method and the like.

In the preparation of the coating solution or dispersion,
In the case of a single-layer type photosensitive layer and in the case of a charge-transporting layer in a laminated type photosensitive layer, the solid content concentration is preferably 40% by weight or less, more preferably 10 to 35% by weight, and the viscosity is preferably 50 to 50% by weight. In the case of a charge generating layer in a laminated photosensitive layer, the solid content concentration is preferably 15% by weight or less, more preferably 1 to 10% by weight, and the viscosity is preferably 0.1 to 10 cps. .

The electrophotographic photosensitive member of the present invention has a surface slipperiness,
Excellent wear resistance and electrical response, and 750-85
Since it has a high sensitivity in the wavelength region of 0 nm, it is suitably used particularly in a copier or a printer using a semiconductor laser as an exposure light source.

In the use of the electrophotographic photosensitive member of the present invention,
As the charger, a corona charger such as a corotron or a scorotron, a contact charger such as a charging roll or a charging brush, or the like is used. Exposure is performed using a halogen lamp, a fluorescent lamp, a laser (semiconductor, He-Ne), an LED, This is performed by a body internal exposure method or the like. The development is performed by a dry development method such as a cascade development, a one-component insulating toner development, a one-component conductive toner development, a two-component magnetic brush development, a wet development method, or the like.
The transfer is performed by electrostatic transfer method such as corona transfer, roller transfer, belt transfer, pressure transfer method, adhesive transfer method, etc., and the fixing is performed by heat roller fixing, flash fixing, oven fixing, pressure fixing, etc. Cleaning is performed using a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, or the like.

[0057]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the invention.

Production Example 1 of Polyarylate Resin 940 ml of deionized water and 26.94 g of sodium hydroxide were charged into a 1 liter beaker, dissolved while stirring with nitrogen bubbling, and then 1.79 g of 2,3,6-trimethylphenol. 0.34 g of benzyltriethylammonium chloride, 61.40 g of bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F], and 2,2-bis (4'-hydroxyphenyl) propane [bisphenol A] 2.88
g, and dissolved under stirring. Then, the alkali aqueous solution was transferred to a 2 liter reaction tank, and a solution prepared by dissolving 49.96 g of terephthalic acid chloride and 2.63 gg of isophthalic acid chloride in 470 ml of dichloromethane was stirred at 20 ° C. The reaction was stopped by adding 8.88 ml of acetic acid and 470 ml of dichloromethane. After stirring for 30 minutes, the organic phase was separated. Was washed twice with 940 ml of a 0.1N aqueous sodium hydroxide solution, and
After washing twice with 10 ml and twice with 710 ml of deionized water, the organic phase was poured into 5000 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure to obtain m- in formula (I). The ratio of the structural unit that is a phenylene group is 5 mol% with respect to the total of the structural unit that is a p-phenylene group and the structural unit that is an m-phenylene group, where A in the general formula (II) is a phenylene group, and n is 1, the proportion of the structural unit in which X is a dimethylmethylene group or an m-phenylene group is 5 mol% with respect to the total of the structural unit in the p-phenylene group and the structural unit in the m-phenylene group; A polyarylate resin in which the ratio of the structural unit of (I) was 95 mol% and the ratio of the structural unit of the general formula (II) was 5 mol% was obtained. The viscosity average molecular weight of the obtained polyarylate resin was measured by the following method.
400. The results are shown in Table 1 below.

A viscosity average molecular weight resin sample was dissolved in dichloromethane to give a concentration c of 6.00.
g / l of solution was prepared and the flow-down time t _{0 of} dichloromethane was
There is used an Ubbelohde capillary viscometer of 136.16 seconds, to measure the flow time t ₁ of the resin solution in a constant temperature bath set at 20.0 ° C., it was calculated viscosity average molecular weight according to the following formula. (1) Relative viscosity η _rel = t ₁ / t ₀ (2) Specific viscosity η _sp = η _rel -1 (3) a = 0.438 × η _sp +1 (4) b = 100 × η _sp / c (5) ) Viscosity η = b / a (6) Viscosity average molecular weight Mv = 3207 × η ^1.205

Preparation Example 2 of Polyarylate Resin 600 ml of deionized water and 7.25 g of sodium hydroxide were charged into a 1 liter beaker, dissolved while stirring with nitrogen bubbling, and then 0.48 g of 2,4,6-trimethylphenol was added. , 0.09 g of benzyltriethylammonium chloride and bis (3,5-dimethyl-4-
After adding 17.39 g of (hydroxyphenyl) methane [tetramethylbisphenol F] and dissolving with stirring,
This alkaline aqueous solution was transferred to a 1-liter reaction vessel, and a solution of 14.15 g of terephthalic acid chloride dissolved in 300 ml of dichloromethane was added dropwise at 20 ° C. over 1 hour with stirring, and further reacted for 5 hours with stirring. Acetic acid 2.39m
and 150 ml of dichloromethane were added to terminate the reaction. After stirring for 30 minutes, the organic phase was separated, and the organic phase was washed twice with 340 ml of a 0.1N aqueous sodium hydroxide solution. After washing twice with 340 ml and twice with 340 ml of deionized water, the organic phase was poured into 2500 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure to obtain m- in the above formula (I). A polyarylate resin having a phenylene group constituent ratio and a viscosity average molecular weight as shown in Table 1 was obtained.

Preparation Example 3 of Polyarylate Resin A 1-liter beaker was charged with 282 ml of deionized water and 8.06 g of sodium hydroxide, and dissolved while stirring with nitrogen bubbling.
4 g, benzyltriethylammonium chloride 0.
09 g and bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F]
After adding 19.84 g and dissolving with stirring, this aqueous alkali solution was transferred to a 1-liter reaction tank, and dichloromethane 141 was added.
A solution prepared by dissolving 11.24 g of terephthalic acid chloride and 4.82 g of isophthalic acid chloride in 20 ml of the solution was added to 20 ml of the solution.
The mixture was added dropwise with stirring at 1 ° C. over 1 hour, and further reacted for 3 hours with stirring.
The reaction was stopped by adding 0 ml, and after stirring for another 30 minutes,
The organic phase was separated and the organic phase was washed twice with 210 ml of 0.1N aqueous sodium hydroxide solution, twice with 210 ml of 0.1N aqueous hydrochloric acid solution and twice with 210 ml of deionized water. Was poured into 2,000 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure, whereby the ratio of the structural unit which is the m-phenylene group in the formula (I) and the viscosity average molecular weight are shown in Table 1 below. A polyarylate resin was obtained.

Preparation Example 4 of Polyarylate Resin 600 ml of deionized water and 7.26 g of sodium hydroxide were charged into a 1 liter beaker, dissolved with stirring while bubbling with nitrogen, and then 0.5 ml of pt-butylphenol was added.
5 g, benzyltriethylammonium chloride 0.
09 g and bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F]
After adding 9.86 g and dissolving with stirring, this alkaline aqueous solution was transferred to a 1-liter reaction tank,
A solution prepared by dissolving 7.22 g of terephthalic acid chloride and 7.22 g of isophthalic acid chloride in 1 l was added dropwise at 20 ° C. with stirring over 1 hour, and further reacted with stirring for 3 hours, followed by 2.39 ml of acetic acid. And dichloromethane 150m
The reaction was quenched by the addition of 1 l, and after further stirring for 30 minutes, the organic phase was separated, and the organic phase was washed twice with 600 ml of a 0.1N aqueous sodium hydroxide solution, and further washed with 600 ml of a 0.1N aqueous hydrochloric acid solution. After washing twice with 600 ml of deionized water twice, the organic phase was poured into 2250 ml of methanol,
The precipitated polymer was separated by filtration and dried under reduced pressure to obtain a polyarylate resin having a ratio of the structural unit of m-phenylene group in the formula (I) and a viscosity average molecular weight as shown in Table 1 below. Was.

Preparation Example 5 of Polyarylate Resin 470 ml of deionized water and 13.46 g of sodium hydroxide were charged into a 1 liter beaker, dissolved with stirring while bubbling with nitrogen, and then 1.35 g of 2,3,6-trimethylphenol. 0.17 g of benzyltriethylammonium chloride, 30.27 g of bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F], and 2,2-bis (4'-hydroxyphenyl) propane [bisphenol A] 1.42
g, and dissolved under stirring. Then, the aqueous alkali solution was transferred to a 1-liter reaction tank, and a solution obtained by dissolving 26.28 g of terephthalic acid chloride in 235 ml of dichloromethane was added.
The mixture was added dropwise at 20 ° C. over 1 hour with stirring, and further stirred for 5 hours.
After reacting for an hour, 4.44 ml of acetic acid and 235 ml of dichloromethane were added to stop the reaction. After stirring for 30 minutes, the organic phase was separated, and the organic phase was washed twice with 350 ml of a 0.1N aqueous sodium hydroxide solution. And 0.1N
After washing twice with 350 ml of an aqueous hydrochloric acid solution and twice with 350 ml of deionized water, the organic phase was poured into 2500 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure to obtain the compound represented by the formula (I). The proportion of the structural unit that is an m-phenylene group, A, X in the general formula (II),
And the proportion of the structural unit that is an m-phenylene group,
A polyarylate resin having the ratio of the structural unit of (I) to the structural unit of the general formula (II) and the viscosity average molecular weight as shown in Table 1 was obtained.

Production Example 6 of Polyarylate Resin 470 ml of deionized water and 13.51 g of sodium hydroxide were placed in a 1-liter beaker, dissolved with stirring while bubbling with nitrogen, and then 1.36 g of 2,3,6-trimethylphenol. 0.17 g of benzyltriethylammonium chloride, 28.78 g of bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F], and 2,2-bis (4′-hydroxyphenyl) propane [bisphenol A] 2.85
g, and dissolved under stirring. Then, the aqueous alkali solution was transferred to a 1-liter reaction tank, and a solution obtained by dissolving 26.37 g of terephthalic acid chloride in 235 ml of dichloromethane was added.
The mixture was added dropwise at 20 ° C. over 1 hour with stirring, and further stirred for 5 hours.
After reacting for an hour, the reaction was stopped by adding 4.45 ml of acetic acid and 235 ml of dichloromethane, and after stirring for another 30 minutes, the organic phase was separated and the organic phase was washed twice with 350 ml of a 0.1N aqueous sodium hydroxide solution. And 0.1N
After washing twice with 350 ml of an aqueous hydrochloric acid solution and twice with 350 ml of deionized water, the organic phase was poured into 2500 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure to obtain the compound represented by the formula (I). The proportion of the structural unit that is an m-phenylene group, A, X in the general formula (II),
And the proportion of the structural unit that is an m-phenylene group,
A polyarylate resin having the ratio of the structural unit of (I) to the structural unit of the general formula (II) and the viscosity average molecular weight as shown in Table 1 was obtained.

Preparation Example 7 of Polyarylate Resin 400 ml of deionized water and 4.91 g of sodium hydroxide were charged into a 1 liter beaker, dissolved with stirring while bubbling with nitrogen, and then 0.2 ml of pt-butylphenol was added.
1 g, benzyltriethylammonium chloride 0.1 g
06 g, bis (3,5-dimethyl-4-hydroxyphenyl) methane [tetramethylbisphenol F] 9.6
7 g and 2.15 g of 2,2-bis (4′-hydroxyphenyl) propane [bisphenol A] were added,
After dissolving with stirring, this aqueous alkali solution was transferred to a 1-liter reaction tank, and 4.89 g of terephthalic acid chloride and 4.8 of isophthalic acid chloride were added to 200 ml of dichloromethane.
A solution in which 9 g was dissolved was added dropwise at 20 ° C. with stirring over 1 hour, and further reacted for 3 hours with stirring.
The reaction was stopped by adding 62 ml and 100 ml of dichloromethane, and after further stirring for 30 minutes, the organic phase was separated and the organic phase was washed with 450 ml of a 0.1N aqueous sodium hydroxide solution.
Wash twice and further add 450 ml of 0.1N aqueous hydrochloric acid solution.
After washing twice with 450 ml of deionized water twice, the organic phase was poured into 1500 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure to obtain the compound of the above formula (I).
In the formula (II), A, X and the proportion of the m-phenylene group in the general formula (II), the structural unit in the formula (I) and the general formula
The ratio of the structural unit of (II) and the viscosity average molecular weight are shown in Table 1 below.
The polyarylate resin as shown in was obtained.

Preparation Example 8 of Polyarylate Resin 400 ml of deionized water and 5.84 g of sodium hydroxide were charged into a 1 liter beaker, dissolved with stirring under nitrogen bubbling, and then dissolved in 0.2 ml of pt-butylphenol.
2 g, benzyltriethylammonium chloride 0.
06 g and 2,83 g of 2,2-bis (4′-hydroxyphenyl) propane [bisphenol A] were added and dissolved under stirring.
The solution was transferred to a reaction vessel, and a solution obtained by dissolving 10.37 g of terephthalic acid chloride in 200 ml of dichloromethane was added at 20 ° C.
The mixture was added dropwise over 1 hour with stirring, and further reacted for 3 hours with stirring. Then, 2.61 ml of acetic acid and 100 parts of dichloromethane were added.
The reaction was quenched by adding 3 ml of water, and after stirring for another 30 minutes, the organic phase was separated. The organic phase was washed twice with 450 ml of a 0.1N aqueous sodium hydroxide solution, and further washed with 450 ml of a 0.1N aqueous hydrochloric acid solution. After washing twice with 450 ml of deionized water twice, the organic phase was poured into 1500 ml of methanol, and the precipitated polymer was separated by filtration and dried under reduced pressure, whereby A, X, and And polyarylate resins having the proportions of the structural units of m-phenylene groups as shown in Table 1 below. Incidentally, the viscosity average molecular weight of the polyarylate resin, the resin does not dissolve in dichloromethane,
Measurement was not possible.

[0067]

[Table 1]

Example 1, Comparative Examples 1 to 7 A conductive support having a 700-μm-thick aluminum vapor-deposited layer formed on the surface of a biaxially stretched polyethylene terephthalate resin film having a thickness of 75 μm was used. The following coating liquid for a charge generation layer was applied using a bar coater and dried to form a charge generation layer having a thickness of 0.4 μm.

Coating Solution for Charge Generating Layer To 10 parts by weight of β-oxytitanium phthalocyanine having the following structure as a charge generating material, 150 parts by weight of 4-methoxy-4-methylpentanone-2 was added and pulverized by a sand grind mill. Then, 100 parts by weight of a 1,2-dimethoxyethane solution having a concentration of 5% by weight of polyvinyl butyral ("Denka Butyral @ 6000C" manufactured by Denki Kagaku Kogyo KK) and a phenoxy resin (manufactured by Union Carbide Co., Ltd.) were used as binder resins. "PKHH") 100 parts by weight of a mixture with 100 parts by weight of a 5% by weight strength 1,2-dimethoxyethane solution are added, and an appropriate amount of 1,2 is added.
Add 2-dimethoxyethane to bring the solids concentration to 4% by weight.
Dispersion adjusted to.

[0070]

Embedded image

Next, the following charge transport layer coating solution is applied on the charge generation layer using a film applicator and dried at 120 ° C. for 20 minutes to form a 20 μm thick charge transport layer. An electrophotographic photosensitive member was manufactured.

As the charge transporting material for the coating solution for the charge transporting layer, a compound having the following structure of the above general formula (III) was used.
Polyarylate resin 100 obtained in Production Examples 1 to 8
A solution obtained by further adding 0.03 parts by weight of a silicone oil as a leveling agent to 650 parts by weight and dissolving in 640 parts by weight of a mixed solvent of tetrahydrofuran / toluene (weight ratio: 8/2).

[0073]

Embedded image

At this time, each charge transporting substance coating solution was
The solubility was evaluated by visually observing the dissolution state of the polyarylate resin of each Preparation Example in a tetrahydrofuran / toluene mixed solvent, and the dissolution state after allowing each charge transporting substance coating solution to stand at room temperature for 2 months was evaluated. The storage stability was evaluated by visual observation, and the results are shown in Table 2 below.

Separately, with respect to each of the obtained electrophotographic photosensitive members, the surface slip property, abrasion resistance, and electrical response were evaluated by the methods described below. The results are shown in Table 2 below.

Surface slippery fully automatic friction and wear tester (DFPM- manufactured by Kyowa Interface Science Co., Ltd.)
SS ") and 0.1 mg / c of toner on the surface of the photosensitive layer.
m ^{2 on} the surface of the photoreceptor sample uniformly placed
m, a urethane rubber piece having a width of 1 cm is pressed at an angle of 45 degrees, a load of 200 g, a speed of 5 mm / sec, and a stroke of 20 m.
The coefficient of friction was measured under the conditions of m and 100 repetitions.

Using a wear-resistant Taber abrasion tester (manufactured by Toyo Seiki Co., Ltd.), a diameter of 10
cm of the photoreceptor sample cut into a circle at 23 ° C.
In an atmosphere of 50% RH, the abrasion loss of the photosensitive layer after 1,000 rotations under a condition of a worn wheel CS-10F and no load was measured.

[0078] Electrical responsive electrophotographic Engineers electrophotographic characteristic evaluation apparatus made in accordance with metric ( "Fundamentals and Applications of connection electrophotographic technology" electrophotographic Gakkai, Corona Co. issued, pp 404-405) using a photosensitive The body is affixed to an aluminum drum in a cylindrical shape, and after establishing conduction between the drum and the conductive support of the photoreceptor, the drum is rotated at a constant rotation speed, and the cycle of charging, exposure, potential measurement, and static elimination is performed. An electrical property evaluation test was carried out using an initial surface potential of -700 V and exposure of 780 n
m, static elimination was performed using 660 nm monochromatic light, and the surface potential (V) when 780 nm light was irradiated at 2.4 μJ / cm ^2.
L) in an atmosphere of 25 ° C. and 50% RH (VL: N
N) and under an atmosphere of 5 ° C. and 10% RH (VL: L
L). The time required from the exposure to the potential measurement was 139 milliseconds.

Example 2 A compound having the following structure of the above general formula (III) (where the phenylbutadiene chain on the left side is one of the two benzene rings on the left end in parentheses and the phenylbutadiene chain on the right side is 50 parts by weight of each of the two benzene rings at the right end in the parentheses) and an antioxidant (“Irganox 1” manufactured by Ciba-Geigy)
076 ") was prepared and evaluated in the same manner as in Example 1 except that the charge transport layer coating solution prepared by adding 8 parts by weight was used and evaluated. The results are shown in Table 2 below. .

[0080]

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[0081]

[Table 2]

[0082]

According to the present invention, the photosensitive layer has excellent surface slipperiness, abrasion resistance, and electrical responsiveness, and can be used for preparing a coating solution for forming the photosensitive layer on a conductive support. And an electrophotographic photosensitive member using a binder resin having excellent solvent solubility and storage stability of the coating solution.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/30 C08K 5/30 5/3465 5/3465 C08L 67/03 C08L 67/03 G03G 5/06 313 G03G 5/06 313 (72) Inventor: Akira Fujii, 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Inside of Mitsubishi Chemical Research Laboratory (72) Inventor Protector: 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Mitsubishi Chemical F-term in Yokohama Research Institute, Inc. (Reference) 2H068 AA13 AA20 AA37 BA13 BB20 BB27 BB52 BB53 FA03 FA04 FA05 FA30 4J002 CF161 CF162 EA046 EN016 EN056 ER016 EU026 GS00 4J029 AA04 AB01 AB04 AD01 AE18 BB03A BB12B01B CB12B01B

Claims (10)

[Claims] An electrophotographic photoreceptor having a photosensitive layer formed on a conductive support, wherein a binder resin in the photosensitive layer has a structural unit represented by the following formula (I) as a main repeating unit, And a structural unit represented by the following general formula (II):
An electrophotographic photoreceptor comprising a polyarylate resin containing less than 0 mol%. Embedded image (Formula (I) represents a structural unit in which the phenylene group on the right end is a p-phenylene group and a structural unit in which the m-phenylene group is present, and the ratio of the structural unit that is the m-phenylene group to the total of both structural units is: Less than 30 mol%. [Chemical formula 2] [In the formula (II), A represents an arylene group which may have a substituent, n is 0 or 1, and when n is 1, X is
A single bond or an alkylene group which may have a substituent (however, when it is a methylene group,
It is not the same as the structure in (I). ), A cycloalkylene group which may have a substituent, a phenylene dimethylene group which may have a substituent, an ether group, a carbonyl group, a thioether group, a sulfinyl group, or a sulfonyl group; The benzene ring may have a substituent. Formula (II) represents a structural unit in which the rightmost phenylene group is a p-phenylene group and a structural unit in which the m-phenylene group is a m-phenylene group, and the ratio of the structural unit that is the m-phenylene group to the total of both structural units. Is less than 30 mol%. ] 2. In the general formula (II), A is a phenylene group which may have a substituent, n is 1, X is
The electrophotographic photosensitive member according to claim 1, wherein is an alkylene group which may have a substituent. 3. The electrophotographic photoreceptor according to claim 2, wherein the alkylene group of X is a dialkyl-substituted methylene group. 4. In the formulas (I) and (II), the ratio of the constitutional unit in which the phenylene group on the right end is an m-phenylene group is the same as the constitutional unit in which the p-phenylene group is a p-phenylene group.
The electrophotographic photoreceptor according to any one of claims 1 to 3, wherein the amount is 1 to 9 mol% based on the total of the phenylene group-containing structural units. 5. A polyarylate resin comprising 91 to 99 mol% of a structural unit represented by the above formula (I) and 9-1 mol% of a structural unit represented by the above general formula (II). The electrophotographic photosensitive member according to claim 1. 6. The electrophotographic photosensitive member according to claim 1, wherein the polyarylate resin has a viscosity average molecular weight of 10,000 to 300,000. 7. The photosensitive layer contains a charge-generating substance and a charge-transporting substance, wherein the charge-transporting substance is a carbazole derivative, a hydrazone derivative, an aromatic or heterocyclic amine derivative, a stilbene derivative, and a butadiene derivative, and derivatives thereof. 7. The electrophotographic photoreceptor according to claim 1, wherein the electrophotographic photoreceptor is any compound selected from the group consisting of compounds in which a plurality of compounds are bonded. 8. The electrophotographic photoreceptor according to claim 7, wherein the charge transporting substance is a compound in which a plurality of aromatic or heterocyclic amine derivatives, stilbene derivatives, and butadiene derivatives are bonded. 9. The charge-transporting substance represented by the following general formula (III):
The electrophotographic feeling according to claim 7 or 8, which is a compound to be prepared.
Light body. Embedded image[In the formula (III), Z represents a single bond or a divalent organic group,
Y¹, Y^Two, Y^Three, And Y^FourIs each independently a substituent
Optionally having an arylene group or a substituent
A divalent heterocyclic group which may be¹And n^TwoIs German
Standing for 0 or 1 and n¹And n^TwoIs 0, Y^Five
And Y⁶Are each independently an optionally substituted
Alkyl group, aryl group which may have a substituent, or
A monovalent heterocyclic group which may have a substituent;¹
And n^TwoWhen is 1, Y^FiveAnd Y ⁶Are each independently
An alkylene group which may have a substituent,
Optionally having an arylene group or a substituent
A divalent heterocyclic group;¹, R^Two, R^Three, R^Four, R
^Five, R⁶, R⁷, And R⁸Each independently has a substituent
May have an alkyl group or a substituent
Cycloalkyl group, aryl which may have a substituent
Group, monovalent heterocyclic group which may have a substituent, or water
Represents an elementary atom, m¹, M^Two, M^Three, And m^FourAre independent
Is an integer of 0 to 4. ] 10. The photosensitive layer is of a laminated type comprising two layers: a charge generating layer in which a charge generating substance is dispersed in a binder resin, and a charge transporting layer in which a charge transporting substance is dispersed in a binder resin. 10. The electrophotographic photosensitive member according to any one of 1 to 9.