JPH08254848A - Electrophotographic photoreceptor - Google Patents

Abstract

PURPOSE: To provide such an electrophotographic photoreceptor that not only for a non-contact electrifying method but for contact electrifying method, the photoreceptor has excellent wear resistance, deposition of foreign matter on the surface of the photoreceptor or contamination of the surface is hardly caused, and production of image defects can be decreased. CONSTITUTION: This electrophotographic photoreceptor has a photosensitive layer on a conductive base body. The layer which forms the outermost surface contains at least one kind of charge transfer polyesters having the structure expressed by formula as a part of the repeating structural unit, and moreover, the layer contains a conductive fine power. In formula, R1 and R2 are independently hydrogen atoms, alkyl groups, alkoxy groups, substd. amino groups, halogen atoms, or substd. or unsubstd. aryl groups, X is a substd. or unsubstd. bivalent aromatic group, T is C1-C6 bivalent straight-chain hydrocarbon group or C2-C10 bivalent branched hydrocarbon groups, and k is an integer 0 or 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having an outermost surface layer containing a charge transporting polyester and a conductive fine powder.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic apparatus such as a plain paper copying machine (PPC), a laser printer, an LED printer, a liquid crystal printer, etc., an image forming process of charging, exposing and developing is applied to a photosensitive member such as a rotating drum type. Then, an image is formed, and the formed toner image is transferred to a transfer material and then fixed to obtain a copy. Examples of the photoconductors used in these image forming apparatuses include inorganic photoconductors such as selenium, arsenic-selenium, cadmium sulfide, zinc oxide, and a-Si, and organic photoconductors (OPC). Among them, there are many occasions in which an organic photoconductor that is inexpensive and excellent in terms of manufacturability and disposability is used, and among them, a so-called function-separated type photoconductor in which a charge generation layer and a charge transport layer are laminated has a sensitivity, Since it is excellent in electrophotographic properties such as chargeability and repetitive stability, various proposals have been made and put to practical use. On the other hand, the single-layer type organic photoconductor has manufacturability, production cost, and positive charging system advantages (reduction of ozone generation, uniform charging property), but electrical performance is inferior to that of the laminated photoconductor. However, there is still plenty of room for research and development.

[0003]

The organic photoreceptors that have been proposed so far have been developed to have sufficient performance with respect to electrophotographic characteristics, but since the photosensitive layer is composed of an organic material, Poor durability against mechanical external force. That is, the problem of image quality defect due to abrasion and scratches on the surface of the photoconductor due to direct load from toner, developer, paper, cleaning member, etc. and foreign matter such as toner filming, or corona discharge. There are problems such as deterioration due to low resistance substances such as ozone and nitrogen oxides, and image deletion in high humidity environment caused by the accumulation of paper dust generated from copy paper on the surface of the photoconductor. , Photoreceptor life is regulated.

Further, recently, instead of using the conventional corona charging device, a contact charging method, that is, a conductive member to which a voltage is applied is brought into contact with the surface of the photoconductor to directly inject the charge into the surface of the photoconductor. Various contact charging methods for obtaining a desired charging potential have been proposed (JP-A-63-14).
9966), when these methods are applied to a conventional organic photoreceptor, there are the following problems. That is, 1) In general, an electrophotographic photoreceptor having a charge transport layer in which a low molecular weight charge transport material is molecularly dispersed in a polymeric binder resin as an outermost layer is used. In that case, the charge transport layer is used. If it is repeatedly used with the charging member in direct contact with, the charge transport layer will be abraded significantly, causing deterioration of the charging property, change in sensitivity, etc., and the life of the photoreceptor will be extremely longer than that of the corona charging method. It becomes short. 2) Further, since the charging member is in direct contact with the surface of the photoconductor, problems such as adhesion of foreign matter to the surface of the photoconductor and contamination are likely to occur, and image defects resulting from them appear on the copy.

There are various possible causes for abrasion of the outermost surface layer of the photoconductor and adhesion of foreign matter to the surface of the photoconductor. In the charge transport layer in which a low molecular weight charge transport material is dispersed in a binder resin, contact is caused. Because the current directly flows locally due to the variation in the method, the stress is applied not only to the surface of the photoconductor but also to the inside, and in the method of using not only direct current but also alternating voltage, the charge transport material is deeply connected. The deterioration of the coating resin is promoted. Furthermore, if the charge transport material is locally non-uniformly dispersed, since these deteriorations are also non-uniform, the film strength of the outermost surface layer is reduced and wear is increased.
It is considered that the non-uniform deterioration also forms nuclei to which foreign matters are attached. Therefore, an object of the present invention is not only the conventional non-contact charging method, but also when the contact charging method is applied, the photoconductor has excellent abrasion resistance, and foreign matter adheres to and contaminates the surface of the photoconductor. An object of the present invention is to provide an electrophotographic photosensitive member that can reduce the occurrence of image quality defects without such a situation.

[0006]

The inventors of the present invention have conducted extensive studies to solve these problems, and as a result, have found that a specific material is used not only in the conventional non-contact charging method but also in the contact charging method. As a result, the inventors have found that the photosensitive layer is less worn and image defects due to foreign matter are less likely to occur, and thus the present invention has been completed. That is, the present invention is an electrophotographic photosensitive member having a photosensitive layer on a conductive support, and in the layer forming the outermost surface, the following general formulas (I-1) and (I-
It is characterized by containing at least one kind of charge transporting polyester containing at least one kind of the structure shown in 2) as a partial structure of a repeating structural unit, and further containing conductive fine powder.

[0007]

Embedded image (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a substituted amino group, a halogen atom, or a substituted or unsubstituted aryl group, and X is a substituted or unsubstituted group. Represents a divalent aromatic group, T
Represents a divalent linear hydrocarbon group having 1 to 6 carbon atoms or a divalent branched hydrocarbon group having 2 to 10 carbon atoms, and k represents an integer selected from 0 or 1. )

In the present invention, as the charge-transporting polyester, a polyester represented by the following general formula (II) or (III) is preferably used.

[Chemical 4] [In the formula, A represents a structure represented by the above general formula (I-1) or (I-2), R represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl. Represents a group, and B and B ′ each represent a group —O— (Y—O) _m —R or a group —O— (Y—O) _m —.
Represents CO-Z-CO-O-R '(wherein R has the same meaning as described above, R'is a hydrogen atom, an alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted Represents an aralkyl group, m represents an integer of 1 to 5), Y represents a divalent alcohol residue, Z represents a divalent carboxylic acid residue, m represents an integer of 1 to 5, p represents an integer of 5 to 5000. ]

As the conductive fine powder, at least one selected from the group consisting of antimony oxide, tin oxide, titanium oxide, indium oxide, and a solid solution of tin oxide and antimony or antimony oxide is preferably used.

The present invention will be described in detail below. The photoreceptor of the present invention may have a single-layer photosensitive layer or a laminated structure in which the functional layers are separated. Figure 1
FIG. 6 shows a schematic cross-sectional view of the photoconductor used in the present invention. 1 and 2 show a case where the photosensitive layer has a single layer structure, in which a photosensitive layer 2 is provided on a conductive support 1, and in FIG. 2, an undercoat layer 3 is further provided. ing. 3 to 6 show the case where the photosensitive layer has a laminated structure. In FIG. 3, the charge generation layer 4 and the charge transport layer 5 are sequentially provided on the conductive support 1, and FIG. In, a subbing layer 3 is further provided. Further, in FIGS. 5 and 6, the charge generation layer 4, the charge transport layer 5, and the surface protective layer 6 are sequentially provided on the conductive support 1. In FIG. Is provided with an undercoat layer 3.

Examples of the conductive support include metals such as aluminum, nickel, chromium and stainless steel, as well as aluminum, titanium, nickel, chromium, stainless steel, gold, vanadium, tin oxide, indium oxide and ITO.
Examples thereof include a plastic film provided with a thin film such as the above, paper coated with or impregnated with a conductivity-imparting agent, and a plastic film. These conductive supports are used in any suitable shape such as a drum shape, a sheet shape, a plate shape, but are not limited thereto. Further, if necessary, the surface of the conductive support can be subjected to various treatments within a range that does not affect the image quality. For example, surface oxidation treatment, chemical treatment, coloring treatment, or irregular reflection treatment such as graining can be performed.

An undercoat layer may be further provided between the conductive support and the charge generation layer. This undercoat layer prevents injection of charges from the conductive support to the photosensitive layer during charging of the photosensitive layer having a laminated structure, and also causes the photosensitive layer to be integrally adhered and held to the conductive support. It exhibits an action as an adhesive layer or an action such as prevention of light reflection of the conductive support in some cases.

Materials used for forming the undercoat layer include polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin,
Polyurethane resin, polyimide resin, vinylidene chloride resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl alcohol resin, water-soluble polyester resin, nitrocellulose, casein, gelatin, polyglutamic acid, starch, starch acetate, amino starch, Known materials such as polyacrylic acid, polyacrylamide, zirconium chelate compounds, titanyl chelate compounds, titanyl alkoxide compounds, organic titanyl compounds, and silane coupling agents can be used,
These materials can be used alone or in combination of two or more. Further, fine particles of titanium oxide, silicon oxide, zirconium oxide, barium titanate, silicone resin or the like can be mixed and used. The thickness of the undercoat layer is 0.01 to 10 μm, preferably 0.05 to 2
It is set in the range of μm. As a coating method, a usual method such as a blade coating method, a Meyer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used.

In the present invention, when the photosensitive layer has a laminated structure,
Examples of the charge generating material in the charge generating layer include amorphous selenium, crystalline selenium-tellurium alloy, selenium-arsenic alloy, other selenium compounds and selenium alloys, inorganic photoconductive materials such as zinc oxide and titanium oxide, and phthalocyanine. Organic pigments and dyes such as system, squarylium, anthanthrone, perylene, azo, anthraquinone, pyrene, pyrylium salts and thiapyrylium salts are used. As the binder resin in the charge generation layer, polyvinyl butyral resin, polyvinyl formal resin, partially modified polyvinyl acetal resin, polycarbonate resin, polyester resin, acrylic resin, polyvinyl chloride resin,
Examples thereof include polystyrene resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, silicone resin, phenol resin, poly-N-vinylcarbazole resin, and the like, but are not limited thereto. These binder resins may be used alone or in combination of two or more. The compounding ratio (weight ratio) of the charge generating material and the binder resin is preferably in the range of 10: 1 to 1:10.

When a charge generating layer is further provided, a coating liquid containing the above charge generating material and a binder resin is used. Solvents in that case include methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, Ordinary organic solvents such as methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride and chloroform can be used alone or in combination of two or more. As a coating method when providing the charge generation layer, a blade coating method,
Usual methods such as the Mayer bar coating method, the spray coating method, the dip coating method, the bead coating method, the air knife coating method and the curtain coating method can be mentioned. The thickness of the charge generation layer is generally 0.1 to 5 μm, preferably 0.2 to
2.0 μm is suitable.

When the photosensitive layer has a laminated structure, the charge transport layer comprises
A charge transporting polyester containing at least one of the structures represented by the general formulas (I-1) and (I-2) as a partial structure of a repeating structural unit, and a conductive powder fine powder are contained. First, a charge-transporting polyester containing at least one of the structures represented by the general formulas (I-1) and (I-2) as a partial structure of a repeating structural unit will be described. Of these, the charge-transporting polyesters represented by the general formulas (II) and (III) are preferable, but the general formulas (I-1) and (I-
X in 2), Y in the general formulas (II) and (III)
Specific examples of Z and Z include the following groups.

Examples of X include those selected from the following groups (1) to (5).

Embedded image

[In the formula, R ₃ and R ₄ each represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted aralkyl group, and R ₅ represents hydrogen. An atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a halogen atom, V is selected from the following groups,

[Chemical 6]

{Wherein R ₆ is a hydrogen atom or has 1 carbon atom
~ 4 alkyl groups, W is selected from the following groups,

[Chemical 7] (However, e means an integer of 1 to 3.) a and b
Means an integer of 1 to 10, and c means an integer of 1 or 2. } D means an integer of 0 to 3. ]

Further, Y and Z mean the same groups as those shown in V above. The group T in the above general formulas (I-1) and (I-2) is a divalent straight-chain hydrocarbon group having 1 to 6 carbon atoms or a divalent branched carbon group having 2 to 10 carbon atoms. It represents a hydrogen group, preferably a branched hydrocarbon group having 3 to 7 carbon atoms. The specific structure of the group T is shown below.

[0021]

Embedded image

[0022]

[Chemical 9]

The charge-transporting polyesters represented by the general formulas (II) and (III) are different from each other in the formulas included in these formulas.
It may be a copolymer composed of one or more kinds of repeating structural units. The degree of polymerization of the charge transporting polyesters represented by the general formulas (II) and (III) is in the range of 5 to 5000, preferably 10 to 1000. The weight average molecular weight (Mw) of these charge-transporting polyesters is in the range of 5 × 10 ^{3 to} 7.5 × 10 ⁵ , and more preferably 1 × 10 ^{4 to} 3 × 10 ⁵ . Next, Tables 1 to 8 show specific examples of preferably used repeating structural units represented by the general formulas (I-1) and (I-2). Specific examples of the charge-transporting polyesters represented by the general formulas (II) and (III) that are preferably used are shown in Tables 9 to 14.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

[Table 3]

[0027]

[Table 4]

[0028]

[Table 5]

[0029]

[Table 6]

[0030]

[Table 7]

[0031]

[Table 8]

[0032]

[Table 9]

[0033]

[Table 10]

[0034]

[Table 11]

[0035]

[Table 12]

[0036]

[Table 13]

[0037]

[Table 14]

Further, as the conductive fine powder in the present invention, at least one selected from the group consisting of antimony oxide, tin oxide, titanium oxide, indium oxide, and a solid solution of tin oxide and antimony or antimony oxide is used. . The compounding ratio (weight ratio) of the charge transporting polyester and the conductive fine powder is preferably in the range of 20: 1 to 5: 1.

In the charge transport layer in the present invention, at least one of the above charge transporting polyesters is dissolved in a solvent, and this and conductive powder fine powder are dispersed by an appropriate dispersing method and coated on the charge generating layer. Can be provided by. Examples of the solvent used when providing the charge transport layer include aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene, ketones such as acetone and 2-butanone, and halogenated fats such as methylene chloride, chloroform and ethylene chloride. Ordinary organic solvents such as group hydrocarbons, cyclic or linear ethers such as tetrahydrofuran, dioxane, ethylene glycol and diethyl ether can be used alone or in combination of two or more.

As a method for dispersing the transportable polyester and the conductive fine powder, a dispersing means such as a ball mill, a sand mill, an attritor or a dyno mill is used. Also,
As a coating method, a usual method such as a blade coating method, a Mayer bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method and a curtain coating method can be used. The thickness of the charge transport layer used in the present invention is generally 5 to 50 μm, preferably 10 to
Set in the range of 30 μm.

Further, for the purpose of preventing the deterioration of the photoreceptor due to ozone or oxidizing gas generated in the copying machine, or light or heat, an antioxidant, a light stabilizer, a heat stabilizer or the like is added to the photosensitive layer. Agents can be added. Examples of antioxidants include hindered phenols, hindered amines, paraphenylenediamines, aryl alkanes, hydroquinones, spirochromans, spiroindanones and their derivatives, organic sulfur compounds and organic phosphorus compounds. Examples of the light stabilizer include benzophenone, benzotriazole, dithiocarbamate, and tetramethylpiperidine derivatives. Further, at least one electron-accepting substance can be contained for the purpose of improving sensitivity, reducing residual potential, and reducing fatigue during repeated use. Examples of the electron accepting substance that can be used in the electrophotographic photoreceptor of the present invention include succinic anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrabromophthalic anhydride, tetracyanoethylene, tetracyanoquinodiene. Examples thereof include methane, o-dinitrobenzene, m-dinitrobenzene, chloranil, dinitroanthraquinone, trinitrofluorenone, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid and phthalic acid. Of these, fluorenone, quinone and C
Particularly preferred are benzene derivatives having electron-withdrawing substituents such as 1, CN, and NO ₂ .

In the present invention, an additive can be contained in the photosensitive layer mainly for the purpose of obtaining good surface properties. As this type of additive, those known as modifiers for paints can be used. For example, alkyl-modified silicone oil such as dimethyl silicone oil and aromatic-modified silicone oil such as methylphenyl silicone oil are preferable examples. These additives are added in an amount of 1 to 10,000 based on the solid content of the charge transport layer.
The content may be 0 ppm, preferably 5 to 2,000 ppm.

In the present invention, when the photosensitive layer has a single layer structure, it is formed by mixing the above charge generating material, the above described polymer charge transporting material and the conductive fine powder in a solvent and applying the mixture. be able to. In that case, the mixing ratio is
The compounding ratio (weight ratio) of the polymer charge transport material and the conductive fine powder is preferably in the range of 20: 1 to 5: 1. The compounding ratio (weight ratio) of the polymer charge transport material and the charge generating material is
A range of 5: 1 to 1: 1 is preferred. The thickness of the single-layer photosensitive layer used in the present invention is generally set in the range of 10 to 50 μm, preferably 20 to 40 μm.

Furthermore, in the present invention, a conventionally known low molecular weight charge transporting material is molecularly dispersed in a polymer binder resin in the surface protective layer containing the above charge transporting polyester and conductive fine powder. It can be provided on the charge transport layer or the photosensitive layer having a single layer structure. The compounding ratio (weight ratio) of the polymer charge transport material and the conductive fine powder in the surface protective layer is preferably in the range of 5: 1 to 1: 1.

In the present invention, the thickness of the surface protective layer is generally set in the range of 1 to 10 μm, preferably 2 to 5 μm. As the dispersion method, coating method, solvent and various additives used when the surface protective layer is provided, the same ones as those described for the charge transport layer can be used.

When the electrophotographic photosensitive member of the present invention is used in an electrophotographic method by a contact charging method, the conductive member for contact charging may be in the shape of a brush, a blade, a pin electrode, a roller, or the like. But well,
Above all, it is preferable to use a roller-shaped member. The roller-shaped member is usually composed of a resistance layer, an elastic layer supporting the resistance layer, and a core material from the outside. Further, if necessary, a protective layer can be provided outside the resistance layer.

The material of the core material has conductivity, and iron, copper, brass, stainless steel, aluminum, nickel, etc. are generally used. In addition, a resin molded product in which conductive particles and the like are dispersed can be used. The material of the elastic layer has conductivity or semiconductivity, and is generally a rubber material in which conductive particles or semiconductive particles are dispersed. As the rubber material, EPDM, polybutadiene, natural rubber, polyisobutylene, SBR, C
R, NBR, silicone rubber, urethane rubber, epichlorohydrin rubber, SBS, thermoplastic elastomer, norbornene rubber, fluorosilicone rubber, ethylene oxide rubber and the like are used. As the conductive particles or semi-conductive particles, carbon black, zinc, aluminum,
Metals such as copper, iron, nickel, chromium and titanium, Zn
_{O-Al 2 O 3, SnO} 2 -Sb 2 O 3, In 2 O 3 -
_{SnO 2, ZnO-TiO 2,} MgO-Al 2 O 3, F
_{eO-TiO 2, TiO 2,} SnO 2, Sb 2 O 3, I
A metal oxide such as n ₂ O ₃ , ZnO or MgO can be used. You may use these materials individually or in mixture of 2 or more types. When two or more kinds are mixed and used, one of them may be in the form of fine particles. Further, fine particles of fluororesin can also be used.

The resistance layer and the protective layer are made of a binder resin in which conductive particles or semiconductive particles are dispersed to control the resistance, and the resistivity is 10 ³ to 10 ¹⁴ Ωcm.
Preferably 10 ⁵ to 10 ¹² Ωcm, more preferably 1
It is in the range of 0 ⁷ to 10 ¹² Ωcm. The film thickness is 0.0
It may be set in the range of 1 to 1000 μm, preferably 0.1 to 500 μm, and more preferably 0.5 to 100 μm. Examples of the binder resin include acrylic resin, cellulose resin, polyamide resin, methoxymethylated nylon, ethoxymethylated nylon, polyurethane resin, polycarbonate resin, polyester resin such as polyethylene terephthalate (PET), polyolefin resin such as polyethylene resin, and polychlorinated resin. Vinyl resin, polyarylate resin,
Polythiophene resin, styrene-butadiene resin, etc. are used. As the conductive particles or semi-conductive particles, carbon black, metal and metal oxide similar to those used for the elastic layer are used.

If necessary, antioxidants such as hindered phenol and hindered amine, fillers such as clay and kaolin, and lubricants such as silicone oil can be added. As means for forming these layers, a blade coating method, a Mayer bar coating method,
The spray coating method, the dip coating method, the bead coating method, the air knife coating method, the curtain coating method, the vacuum deposition method, the plasma coating method, etc. can be mentioned.

[0050]

In an image forming apparatus equipped with a charging device using these conductive members, when the electrophotographic photosensitive member is charged, a voltage is applied to the conductive member. It is preferable to superimpose a voltage, and it is difficult to obtain uniform charging only with a DC voltage. As for the range of voltage, positive or negative 50 to 2 for DC voltage
The range of 000V is preferable, and the range of 100 to 1500V is particularly preferable. The AC voltage to be superimposed has a peak-to-peak voltage of 400 to 1800 V, preferably 800 to 1600.
V, and more preferably 1200 to 1600V. When the peak-to-peak voltage exceeds 1800V, more uniform charging cannot be obtained as compared with the case where no AC voltage is superposed.
The frequency of the alternating voltage is preferably 100 to 2000 Hz.

[0051]

EXAMPLES The present invention will be described below with reference to examples.
The invention is not limited by these examples. The following "parts" mean "parts by weight".

Example 1 On an aluminum pipe, 10 parts of a zirconium compound (Organix ZC540, manufactured by Matsumoto Pharmaceutical Co., Ltd.) and 1 part of a silane compound (A110, manufactured by Nippon Unicar Co., Ltd.) and i
A solution consisting of 40 parts of propanol and 20 parts of butanol was applied by a dip coating method and dried by heating at 150 ° C. for 10 minutes to form an undercoat layer having a film thickness of 0.1 μm. 10 parts of chlorogallium phthalocyanine having a powder X-ray diffraction pattern shown in FIG. 7 was mixed with 15 parts of vinyl chloride-vinyl acetate-vinyl acetate copolymer (VMCH, manufactured by Nippon Unicar Co., Ltd.) and 300 parts of n-butanol,
After treatment with glass beads in a sand mill for 1 hour to disperse, the obtained coating solution is applied onto the above-mentioned undercoat layer by a dip coating method, and dried by heating at 100 ° C. for 10 minutes to give a film thickness of 0.15 μm. The charge generation layer of was formed. next,
5 parts of the above-mentioned exemplary compound (6) (weight average molecular weight: Mw = 4.2 × 10 ⁴ ) and 1 part of tin oxide as a charge-transporting polyester were mixed with 30 parts of monochlorobenzene and 30 parts of tetrahydrofuran, and mixed with glass beads. After being treated by a sand mill for 1 hour and dispersed, the obtained coating solution was applied on the above charge generation layer by a dip coating method, and dried by heating at 115 ° C. for 1 hour to give a film thickness of 20 μm.
The charge transporting layer was formed to produce an electrophotographic photoreceptor.

Example 2 An electrophotographic image was obtained in the same manner as in Example 1 except that the exemplified compound (34) (Mw = 1.2 × 10 ⁵ ) was used in place of the exemplified compound (6) as the charge transporting polyester. A photoconductor was prepared and evaluated in the same manner. Example 3 An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the exemplified compound (39) (Mw = 1.2 × 10 ⁵ ) was used in place of the exemplified compound (6) as the charge transporting polyester. It was produced and evaluated in the same manner. Example 4 An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the exemplified compound (40) (Mw = 1.1 × 10 ⁵ ) was used in place of the exemplified compound (6) as the charge transporting polyester. It was produced and evaluated in the same manner. Example 5 An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the exemplified compound (73) (Mw = 1.2 × 10 ⁵ ) was used as the charge-transporting polyester in place of the exemplified compound (6). It was produced and evaluated in the same manner.

Comparative Example 1 2 parts of a benzidine compound represented by the following structural formula (IV):
Polycarbonate resin composed of repeating structural units represented by structural formula (V) (viscosity average molecular weight: Mv = 39.00)
0) A coating solution prepared by dissolving 3 parts in 20 parts of monochlorobenzene was applied on the charge generation layer formed in the same manner as in Example 1 by a dip coating method, and dried by heating at 115 ° C. for 1 hour to give a film thickness of 20 μm. The charge transporting layer was formed to produce an electrophotographic photoreceptor.

[Chemical 10] Comparative Example 2 An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that tin oxide was removed from the coating liquid for the charge transport layer of Example 1.

Example 6 As a charge-transporting polyester, 5 parts of Exemplified compound (6) (weight average molecular weight: Mw = 4.2 × 10 ⁴ ) and 1 part of tin oxide / antimony oxide (weight ratio 85/15) were prepared. After mixing with 30 parts of monochlorobenzene and 30 parts of tetrahydrofuran and treating with glass beads in a sand mill for 1 hour to disperse, the resulting coating solution is applied onto the charge transport layer of Comparative Example 1 by a dip coating method, and 115 ° C. Was heated and dried for 1 hour to form a surface protective layer having a film thickness of 4 μm, and an electrophotographic photosensitive member was manufactured.

Example 7 An electrophotographic image was obtained in the same manner as in Example 6 except that the exemplified compound (3) (Mw = 1.1 × 10 ⁵ ) was used in place of the exemplified compound (6) as the charge transporting polyester. A photoconductor was manufactured. Example 8 An electrophotographic photosensitive member was prepared in the same manner as in Example 6 except that the exemplified compound (41) (Mw = 1.3 × 10 ⁵ ) was used in place of the exemplified compound (6) as the charge transporting polyester. Manufactured.

Comparative Example 3 An electrophotographic photosensitive member was produced in the same manner as in Example 7 except that tin oxide / antimony oxide was removed from the coating solution for the surface protective layer of Example 7. Comparative Example 4 An electrophotographic photosensitive member was produced in the same manner as in Example 8 except that tin oxide / antimony oxide was removed from the coating liquid for the charge transport layer of Example 8.

Each of the electrophotographic photoconductors manufactured as described above and the following conductive members are connected to a laser beam printer.
(XP-11 remodeling machine, made by Fuji Xerox Co., Ltd.),
A DC voltage of −600 V and an AC voltage of 1.6 KV were applied as a bias current, and a repetitive copying operation was repeated 70,000 times to evaluate the image quality of an image after copying 70,000 times.
The amount of wear of the outermost surface layer of the electrophotographic photosensitive member was measured. The results are shown in Table 15. The conductive member used was a stainless steel rod having a diameter of 6 mm as the core material, and epichlorohydrin rubber having a resistance of 10 ⁶ Ωcm as the elastic layer.
A conductive roll having a diameter of mm was produced.

[0059]

[Table 15]

Further, each electrophotographic photosensitive member was mounted on a laser beam printer (XP-11 remodeling machine, manufactured by Fuji Xerox Co., Ltd.) having an ordinary charging means using a scorotron.
The same evaluation and measurement as above were performed. The results are shown in Table 16.

[Table 16]

[0061]

In the electrophotographic photoreceptor of the present invention, since the layer forming the outermost surface is composed of the above charge transporting polyester and conductive fine particles, it can be used for both the non-contact charging method and the contact charging method. Also, compared with the conventional electrophotographic photoreceptor in which the charge transport material is molecularly dispersed, it is possible to reduce the image quality defect due to the abrasion of the layer forming the surface and the adhesion of foreign matters, and it is possible to remarkably improve the life of the electrophotographic photoreceptor. .

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an example of an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic cross-sectional view of another example of the electrophotographic photosensitive member of the present invention.

FIG. 3 is a schematic cross-sectional view of another example of the electrophotographic photosensitive member of the present invention.

FIG. 4 is a schematic cross-sectional view of another example of the electrophotographic photosensitive member of the present invention.

FIG. 5 is a schematic cross-sectional view of another example of the electrophotographic photosensitive member of the present invention.

FIG. 6 is a schematic cross-sectional view of another example of the electrophotographic photosensitive member of the present invention.

7 is a graph showing a powder X-ray diffraction pattern of chlorogallium phthalocyanine used in Example 1. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conductive support, 2 ... Photosensitive layer, 3 ... Undercoat layer, 4 ... Charge generation layer, 5 ... Charge transport layer, 6 ... Surface protective layer.

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[Procedure amendment]

[Submission date] April 25, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

[0025]

[Table 2]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

[0026]

[Table 3]

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

[0029]

[Table 6]

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

[0030]

[Table 7]

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction content]

[0036]

[Table 13]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiro Ozeki 1600 Takematsu, Minamiashigara City, Kanagawa Prefecture Fuji Xerox Co., Ltd.

Claims (7)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein at least the structure represented by the following general formulas (I-1) and (I-2) is contained in the layer forming the outermost surface. An electrophotographic photoreceptor containing at least one charge-transporting polyester containing one kind as a partial structure of a repeating structural unit, and further containing a conductive fine powder. Embedded image (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a substituted amino group, a halogen atom, or a substituted or unsubstituted aryl group, and X is a substituted or unsubstituted group. Represents a divalent aromatic group, T
Represents a divalent linear hydrocarbon group having 1 to 6 carbon atoms or a divalent branched hydrocarbon group having 2 to 10 carbon atoms, and k represents an integer selected from 0 or 1. ) 2. A charge transporting polyester is represented by the following general formula (I
The electrophotographic photosensitive member according to claim 1, which is a polyester represented by I) or (III). Embedded image [In the formula, A represents a structure represented by the above general formula (I-1) or (I-2), R represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl. Represents a group, and B and B ′ each represent a group —O— (Y—O) _m —R or a group —O— (Y—O) _m —.
Represents CO-Z-CO-O-R '(wherein R has the same meaning as described above, R'is a hydrogen atom, an alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted Represents an aralkyl group, m represents an integer of 1 to 5), Y represents a divalent alcohol residue, Z represents a divalent carboxylic acid residue, m represents an integer of 1 to 5, p represents an integer of 5 to 5000. ] 3. The conductive fine powder is at least one selected from the group consisting of antimony oxide, tin oxide, titanium oxide, indium oxide, and a solid solution of tin oxide and antimony or antimony oxide. Item 1. The electrophotographic photosensitive member according to item 1. 4. The particle size distribution of the conductive fine powder has a particle size of 1 μm.
The electrophotographic photosensitive member according to claim 1 or 3, wherein the content of the above particles is 1% by weight or less and the content of particles having a particle size of 0.3 µm or less is 50% by weight or more. 5. The electrophotographic photoreceptor according to claim 1, wherein at least a charge generation layer is provided between the layer containing the charge transporting polyester and the conductive fine powder and the conductive support. . 6. The electrophotographic photosensitive member according to claim 1, wherein the layer forming the outermost surface is a charge transport layer. 7. The electrophotographic photosensitive member according to claim 1, wherein the layer forming the outermost surface is a surface protective layer.