JP3084861B2 - Electrophotographic photoreceptor - Google Patents

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 excellent mechanical properties. It is useful because it can be improved.

[0002]

2. Description of the Related Art In recent years, electrophotographic technology has been widely used and applied not only in the field of copiers but also in the field of various printers because of its immediacy and high-quality images. Photoconductors, the core of electrophotographic technology, are made of conventional inorganic photoconductors such as selenium, arsenic-selenium alloy, cadmium sulfide, and zinc oxide as photoconductive materials. A photoreceptor using an organic photoconductive material having advantages such as easy manufacturing and the like has been developed. Among the organic photoconductors, a so-called stacked photoconductor in which a charge generation layer and a charge transfer layer are stacked has been invented and has become the mainstream of research. The stacked photoreceptor can be obtained by combining a highly efficient charge generating substance and a charge transfer substance to provide a highly sensitive photoreceptor, a wide selection of materials, and a highly safe photoreceptor. Because of its high productivity and relatively low cost, it is highly likely that it will become the mainstream of photoreceptors, and has been intensively developed.

[0003]

Normally, such a photoreceptor is repeatedly used in an electrophotographic process, that is, in a cycle of charging, exposure, development, transfer, cleaning, charge elimination, etc., so that the photoreceptor deteriorates under various stresses during the process. I do.
Such deterioration includes, for example, strong oxidizing ozone or N2 generated from a corona charger commonly used as a charger.
O _x is or apply any chemical damage to the photosensitive layer, the carrier generated in the image exposure (current) flows in the light-sensitive layer or discharging light, chemical due decompose the photosensitive layer composition by light from the outside And electrical degradation. Further, other deteriorations include mechanical deterioration such as abrasion and scratches on the surface of the photosensitive layer due to rubbing of a cleaning blade, a magnetic brush or the like, contact with a developer or paper, and peeling of a film. In particular, such damage on the surface of the photosensitive layer is likely to appear on a copy image and directly impairs image quality, which is a major factor that limits the life of the photosensitive member. That is, in order to develop a photoreceptor having a long life, it is an essential condition to increase the electrical and chemical durability as well as the mechanical strength.

An example in which an overcoat layer is provided to increase the mechanical strength of a photoreceptor (JP-A-61-72)
No. 256), an example using a binder polymer having high abrasion resistance (Japanese Patent Application Laid-Open No. 57-30841), and an example using a polymer having a small friction coefficient (Japanese Patent Application Laid-open No. 60-2).
[0004] Japanese Patent Application Laid-Open No. 1-307761 and Japanese Patent Application Laid-Open No. 56-1.
Various proposals have been made, such as those described in Japanese Patent Application Laid-Open No. 26838). However, at present, these cases often involve problems such as insufficient effects and adverse effects on other characteristics.

On the other hand, there has been proposed a method of using a polysiloxane-polycarbonate block copolymer as a binder for the purpose of improving the sliding property and sliding property of the photosensitive member surface (JP-A-61-132954, JP-A-61-132954). 2-2
No. 40655), a small amount of siloxane is insufficiently effective. On the other hand, when a siloxane copolymer having a high content is used, there is a problem of adverse effects on other characteristics such as electric characteristics.

[0006]

In view of this situation, the present inventors have focused on the surface slipperiness among the mechanical strengths and minimized the contact resistance with the cleaning blade and the developer as much as possible. As a result of intensive studies on techniques to increase the slipperiness of the photoreceptor surface in order to minimize the mechanical damage caused, it was found that other characteristics could be achieved by including a polycarbonate resin with a specific polysiloxane in the side chain in the photosensitive layer. It has been found that the surface smoothness can be enhanced and the abrasion resistance can be improved without having any influence on the present invention, and the present invention has been completed.

That is, the gist of the present invention is to provide an electrophotographic photosensitive member having at least a photosensitive layer on a conductive substrate, wherein the photosensitive layer comprises a charge generating substance, a charge transporting substance, and a structural unit represented by the following general formula (1). Electrophotographic photoreceptor characterized by containing a polycarbonate resin having a polysiloxane in a side chain

[0008]

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And R ₁ and R ₂ represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group, and Z represents a substituted or unsubstituted carbon atom having 4 to 20 carbon atoms. Y ₁ to Y _{4 each} represent a polysiloxane group, a hydrogen atom, an allyl group, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group represented by the following general formula (2); At least one of Y ₁ to Y ₄ is the polysiloxane group;

[0010]

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In the general formula (2), R ₃ represents an alkylene group having 2 to 5 carbon atoms, and R ₄ to R ₈ represent an alkyl group, an aryl group or a fluoroalkyl group having 1 to 20 carbon atoms. Represents an integer of 1 to 500. ). Hereinafter, the present invention will be described in more detail.

Specific constitutions of the photosensitive layer according to the present invention are as follows: a charge generation layer mainly composed of a charge generation substance, a charge transportation layer mainly composed of a charge transport substance and a binder resin on a conductive support in this order. Stacked photoconductor. An inverted two-layered photoconductor in which a charge transport layer mainly composed of a charge transport substance and a binder resin and a charge generation layer mainly composed of a charge generation substance are laminated in this order on a conductive support; A dispersion type photoconductor in which a charge generation substance is dispersed in a layer containing a charge transport substance and a binder resin on a conductive support. Such a configuration is given as an example of a basic form.

The photoreceptor of the present invention is provided on a conductive support. Examples of the conductive support include metallic materials such as aluminum, stainless steel, copper, and nickel; insulating supports such as polyester films and paper provided with a conductive layer such as aluminum, copper, palladium, tin oxide, and indium oxide on the surface. Is used. A known barrier layer, which is usually used, may be provided between the conductive support and the charge generation layer.

Examples of the barrier layer include an anodized aluminum film, an inorganic layer such as aluminum oxide and aluminum hydroxide, polyvinyl alcohol, casein, polyvinylpyrrolidone, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide and polyamide. An organic layer is used. In the case of a stacked photoreceptor, the charge generating material used in the charge generating layer is selenium and its alloys, arsenic-selenium, cadmium sulfide, zinc oxide, other inorganic photoconductive materials, phthalocyanine, azo dyes, quinacridone, polycyclic quinone, Various organic pigments and dyes such as pyrylium salts, thiapyrylium salts, indigo, thioindigo, anthantrone, pyranthrone and cyanine can be used. Among them, metals such as metal-free phthalocyanine, copper indium chloride, gallium chloride, tin, oxytitanium, zinc, and vanadium or oxides thereof, phthalocyanines in which chloride is coordinated, azo pigments such as monoazo, bisazo, trisazo, and polyazos. preferable. The charge generating layer is made of fine particles of these substances such as polyester resin, polyvinyl acetate, polyacrylate, polymethacrylate, polyester, polycarbonate, polyvinyl acetoacetal, polyvinyl propional, polyvinyl butyral, phenoxy resin, epoxy resin,
It may be used in a dispersion layer in a form bound with various binder resins such as urethane resin, cellulose ester, cellulose ether and the like. In this case, the binder resin 1 is used.
It is used in an amount of 30 to 500 parts by weight with respect to 00 parts by weight, and its film thickness is usually 0.1 μm to 2 μm, preferably 0.15 μm to 0.8 μm. Further, the charge generation layer may contain various additives such as a leveling agent, an antioxidant, and a sensitizer for improving coating properties, if necessary. Further, the charge generation layer may be a deposited film of the above charge generation material.

Examples of the charge transport material used in the charge transport layer include carbazole, indole, imidazole,
Hexacyclic compounds such as oxazole, pyrazole, oxadiazole, pyrazoline, thiadiazole, aniline derivatives, hydrazone compounds, aromatic amine derivatives, stilbene derivatives, or polymers having a group consisting of these compounds in the main chain or side chain. Electron donating substances.

The polycarbonate resin of the present invention is used as a main binder resin of the charge transport layer. In addition, for example, vinyl polymers such as polymethyl methacrylate, polystyrene and polyvinyl chloride and copolymers thereof, various polycarbonates, polyesters, It may be used together with polyester carbonate, polysulfone, polyimide, phenoxy, epoxy, silicone resin or partially cross-linked cured product thereof.

The polycarbonate resin of the present invention is characterized by having a polysiloxane in the side chain containing the structural unit represented by the above general formula (1), and having the structure represented by the general formula (1) A polycarbonate resin containing a structural unit represented by the general formula (1), a polycarbonate resin containing a structural unit represented by the general formula (1), and / or a polycarbonate resin containing the structural unit represented by the general formula (1) It contains a polycarbonate resin composition.

The content of the side chain polysiloxane is preferably 0.01% by weight to 20% by weight, more preferably 0.1% by weight to 15% by weight, based on the polycarbonate resin. When the content is less than 0.01% by weight, the effect of improving the physical properties by introducing a polysiloxane structure is insufficient, and
If the content is more than 10% by weight, transparency and electrical properties are adversely affected. Other copolymerization components of the copolymerized polycarbonate resin having the structural unit represented by the general formula (1) are represented by the following general formula (3)
Is represented by one or more structural units represented by

[0019]

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Wherein R ₁ and R ₂ are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group, and Z is a substituted or unsubstituted C _{4 to} C 20 group. Represents a carbocycle, B ₁ to B ₄ are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms,
It represents an aryl group or a halogenated alkyl group.

The other resin to be mixed in the polycarbonate resin containing the structural unit represented by the general formula (1) and / or the polycarbonate resin composition containing the copolymerized polycarbonate resin is represented by the general formula (3). It is a resin having one or more structural units. Examples of the dihydric phenol compound that provides another copolymerization component or another mixed resin include bis- (4-hydroxyphenyl) methane, 1,1-bis- (4-hydroxyphenyl) ethane, and 1,1-bis. -(4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) propane, ie, bisphenol A, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis-
(4-hydroxyphenyl) pentane, 2,2-bis-
(4-hydroxyphenyl) -3-methylbutane, 2,
2-bis- (4-hydroxyphenyl) hexane, 2,
2-bis- (4-hydroxyphenyl) -4-methylpentane, 1,1-bis- (4-hydroxyphenyl) cyclopentane, 1,1-bis- (4-hydroxyphenyl) cyclohexane, bis- (4- (Hydroxy-3-methylphenyl) methane, 1,1-bis- (4-hydroxy-3-methylphenyl) ethane, 2,2-bis- (4
-Hydroxy-3-methylphenyl) propane, 2,2
-Bis- (4-hydroxy-3-ethylphenyl) propane, 2,2-bis- (4-hydroxy-3-isopropylphenyl) propane, 2,2-bis- (4-hydroxy-3-sec-butylphenyl) ) Propane, bis-
(4-hydroxyphenyl) phenylmethane, 1,1-
Bis- (4-hydroxyphenyl) -1-phenylethane, 1,1-bis- (4-hydroxyphenyl) -1-
Phenylpropane, bis- (4-hydroxyphenyl)
Diphenylmethane, bis- (4-hydroxyphenyl)
Examples thereof include dibenzylmethane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfide, and phenolphthalein.

The polycarbonate resin containing the structural unit represented by the general formula (1) is obtained by polymerizing or copolymerizing a dihydric phenol compound containing a dihydric phenol having a corresponding polysiloxane in a side chain, or a carbon-carbon double bond. Is produced by a hydrosilylation reaction of a polysiloxane having a Si-H structure at one end to a polycarbonate having a side chain.
The dihydric phenol having a polysiloxane in the side chain is carbon-
Divalent phenol having carbon double bond in side chain and Si at one end
It is synthesized by a hydrosilylation reaction of a polysiloxane having an —H structure.

The dihydric phenol compound having a carbon-carbon double bond in the side chain is represented by the following general formula (4).

[0024]

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Wherein R ₁ and R ₂ are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms,
Represents an aryl group or a halogen-substituted alkyl group, and Z represents an optionally substituted carbocyclic ring having 4 to 20 carbon atoms.

[0026]

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[0027] Also, Y _'1 to Y' ₄ carbon 5 2 -C - at least one functional group containing a carbon-carbon double bond, a hydrogen atom, a halogen atom, alkyl of 1 to 20 carbon atoms, aryl Or a halogen-substituted alkyl group, more preferably an allyl group, a vinyl group, a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms,
An aryl group or a halogen-substituted alkyl group, more preferably an allyl group, a vinyl group or a hydrogen atom, wherein at least one of Y ′ ₁ to Y ′ ₄ has a carbon-carbon double bond Group.

The above 2 having a carbon-carbon double bond in the side chain
Specifically, the divalent phenol compound is 2,2-bis (4
-Hydroxy-3-vinylphenyl) propane, 2,2
-Bis (4-hydroxy-3-allylphenyl) propane, 2,2-bis- (4-hydroxy-3,5-divinylphenyl) propane, 2,2-bis (4-hydroxy-3,5-diallylphenyl) ) Propane and the like can be mentioned, and among them, it is more preferable to use diallyl bisphenol A, which is generally called by the following formula, in view of availability and reactivity of hydrosilylation reaction.

[0029]

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In the present invention, the polymerization or copolymerization of the dihydric phenol compound containing a dihydric phenol having a polysiloxane in the side chain is usually carried out by any method for synthesizing a polycarbonate, such as an interfacial polymerization method, a pyridine method or a melt polymerization method. However, the interfacial polymerization method is more preferable because of easiness of purification of the produced polymer and improvement of the molecular weight.

In the synthesis of copolymerized polycarbonate by interfacial polymerization, specifically, an aqueous alkali solution is added as an acid acceptor to a dihydric phenol compound in the presence of an inert solvent such as methylene chloride, 1,2-dichloromethane or chloroform.
This is achieved by introducing and reacting phosgene. Here, the reaction rate can be increased by appropriately adding a catalyst such as a tertiary amine such as triethylamine and a phase transfer catalyst typified by a quaternary ammonium compound such as tetrabutylammonium chloride and benzyltributylammonium bromide. Phenol, p-tert-butylphenol, for the purpose of controlling the molecular weight,
Monohydric phenols such as cumylphenol and octylphenol may be allowed to coexist as appropriate. The catalyst or the molecular weight regulator can be added at any time such as at the same time as the phosgenation or after the phosgenation. If necessary, the timing of adding these reaction reagents can be divided into several times. The reaction temperature is suitably from -10C to 100C. Two or more dihydric phenol compounds are polymerized by (a) reacting all of them with phosgene first and simultaneously (b) Some of the dihydric phenol compounds are first reacted with phosgene and then polymerized by adding other components (C) Various methods can be arbitrarily selected, for example, all the components are separately reacted with phosgene, then mixed and polymerized.

Further, in the copolymerization, acid halides such as terephthalic acid chloride, inophthalic acid chloride, adibic acid chloride, sebacic acid chloride and the like and diamines such as piperazine may coexist within a range that does not significantly affect the reaction. Phloroglysin, 1,1,1-tri (4-hydroxyphenyl) ethane, or tetra (4
A small amount of a branching agent typified by a polyhydric phenol such as (-hydroxyphenyl) methane can also be used.

On the other hand, in the hydroxylation reaction of a polysiloxane having a Si-H structure at one end to a polycarbonate having a carbon-carbon double bond in a side chain, the polycarbonate contains at least a dihydric phenol represented by the above general formula (4). Obtained by polymerization as one component. In the present invention, the hydrosilylation reaction is any method generally known as the addition reaction of Si-H to olefins or alkynes, for example, a method using a free radical initiator, a method by light irradiation or high energy irradiation, a Group VIII transition metal compound, etc. Although it is essentially possible to use either a method using a transition metal catalyst or a method using a base catalyst, it is necessary to use a transition metal catalyst in order to carry out hydrosilylation in high yield and minimize side reactions. The method used is preferred.

Specific examples of the transition metal catalyst used in the hydrosilylation reaction of the present invention include platinum complexes typified by chloroplatinic acid, metallic platinum, octacarbonyl2 cobalt, rhodium complexes and the like. The catalyst may be either a homogeneous system or a heterogeneous system. The reaction is usually carried out in a solvent in which the raw material polycarbonate resin or dihydric phenol dissolves or swells, and specifically, halogenated hydrocarbons such as 1,2-dichloroethane, chloroform, carbon tetrachloride, benzene, toluene, Aromatic hydrocarbons such as xylene, chlorobenzene, aromatic halides such as o-dichlorobenzene, methyl ethyl ketone, ethyl acetate, dimethylformamide, dimethyl sulfoxide, anisole, pyridine and the like can be mentioned. From the viewpoint of catalytic activity and the like, it is more preferable to use an aromatic hydrocarbon solvent such as benzene, toluene and xylene. The reaction temperature is preferably 50 ° C. or higher, more preferably 70 ° C. or higher from the viewpoint of reaction activity.

In the present invention, the structure of the polysiloxane grafted to the side chain of the polycarbonate is composed of polyalkylsiloxane, polyarylsiloxane, or one or more of polyalkylarylsiloxane, polyfluoroalkylsiloxane, and polyfluoroalkylarylsiloxane. Homopolymer or copolymer, specifically, polydimethylsiloxane, polydiethylsiloxane, polydiphenylsiloxane, polymethylphenylsiloxane, and the like.

The chain length of the polysiloxane side chain is such that n in the general formula (2) is 1 to 500, preferably 10 to 400, and more preferably 20 to 300. When n is 1 or less, the effect of improving the physical properties by introducing a siloxane structure is not remarkable, while when it is 500 or more, production is difficult. The molecular weight of the polycarbonate resin having a polysiloxane of the present invention in the side chain is from 10,000 to 300,000, more preferably from 20,000 to 150,000 in terms of viscosity average molecular weight. When the molecular weight is 10,000 or less, the mechanical strength is insufficient, while 30
If it is more than 000, film formation is difficult and not suitable.

The viscosity average molecular weight ( _Mv ) referred to here
Is a solution of 6.0 g / l of polymer in methylene chloride,
From ηsp measured at 20 ° C., the following equations (5) and (6)
It is a value obtained from: ηsp / C = [η] (1 + K′ηsp) (5) [η] = K (M _v ) α (6) C: Polymer concentration (g / L), K ′ = 0.28, K =
1.23 × 10 ^-5 α = 0.83, [η]: intrinsic viscosity, M _v : viscosity average molecular weight

The polycarbonate resin having a polysiloxane in the side chain used in the present invention is used by adding it to the outermost surface layer of the photosensitive layer, and is most effective particularly when it is used as a binder resin of a charge transport layer. It is. In this case, the ratio of the charge transporting agent is from 30 to 100 parts by weight of the polycarbonate resin having the polysiloxane of the present invention in the side chain.
It is used in an amount of 300 parts by weight, preferably 40 to 200 parts by weight, more preferably 40 to 150 parts by weight.

The charge transport layer may contain various additives such as an antioxidant and a sensitizer, if necessary. The thickness of the charge transport layer is 10 to 60 μm, preferably 10 to 45 μm.
It is good to use with a thickness of μm. In the case of the dispersion type photosensitive layer, the above-mentioned charge generating substance is dispersed in the charge transport medium containing the polycarbonate resin having the polysiloxane of the present invention in the side chain and having the above-described mixing ratio. In this case, the particle size must be sufficiently small, and is preferably 1 μm or less, more preferably 0.5 μm or less. If the amount of the charge generating substance dispersed in the photosensitive layer is too small, sufficient sensitivity cannot be obtained. If the amount is too large, adverse effects such as a decrease in chargeability and a decrease in sensitivity occur. %, More preferably in the range of 1 to 20% by weight. The thickness of the photosensitive layer is usually 5 to 50 μm, more preferably 10 to 45 μm. Also in this case, a known plasticizer for improving film formability, flexibility, mechanical strength, etc., an additive for suppressing residual potential, a dispersion auxiliary for improving dispersion stability, and a coating property. Leveling agents, surfactants, such as silicone oils, to improve
Fluorine-based oil and other additives may be contained.

These photoreceptors may be provided with an overcoat layer mainly composed of a conventionally known thermoplastic or thermosetting polymer as the outermost surface. These photosensitive layers are formed on a conductive support by a known method such as roll coating, bar coating, dip coating, spoon coating, and multi-nozzle coating.

As a method for forming each layer, a known method such as sequentially applying a coating solution obtained by dissolving or dispersing a substance to be contained in a layer in a solvent can be applied.

[0042]

According to the present invention, an electrophotographic photosensitive member containing a polycarbonate resin having a specific polysiloxane in a side chain in the photosensitive layer according to the present invention has no adverse effect on electric characteristics and the like, and has no slippage on the surface and sliding. The remarkable improvement in the performance of the photoconductor makes it difficult to be damaged by a cleaning blade, a developer, or the like, which is extremely effective in extending the life of the photoconductor, and is useful for a high-speed copying machine or printer.

[0043]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, which should not be construed as limiting the scope of the invention. The repeating structural units of the polycarbonate resin used in each of the following examples are represented as (a), (b), and (c) as follows.

[0044]

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[0045]

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[0046]

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Example 1 10 parts by weight of a bisazo compound having the following structure was added to 150 parts by weight of 4-methoxy-4-methylpentanone 2,
Pulverization and dispersion treatment was performed with a sand grind mill. The pigment dispersion obtained here was treated with polyvinyl butyral (trade name # 6000-C, manufactured by Denki Kagaku Kogyo KK) in 5%
3. In addition to the dimethoxyethane solution, finally a solid concentration of 4.
A 0% dispersion was made.

The thus obtained dispersion is applied to the surface of a polyethylene terephthalate film having a surface on which aluminum is vapor-deposited, using a wire bar, and the charge generation layer is coated so that the dry film thickness becomes 0.4 g / m ^2. Provided.

[0049]

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Next, 95 parts by weight of a hydrazone compound was added onto the charge generation layer.

[0051]

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The above structural units (a), (b) and (c)
The weight ratio of 49: 49: 2 including, a polycarbonate resin having a polysiloxane side chain (M _v 32,400)
A solution prepared by dissolving 100 parts by weight of a mixed solvent of 1,4-dioxane and tetrahydrofuran is applied by an applicator, and dried at room temperature for 30 minutes and at 125 ° C. for 30 minutes so that the film thickness after drying becomes 21 μm. A charge generation layer was provided.

The electrophotographic photoreceptor thus prepared was used as a photoreceptor characteristic measuring device (Model EPA-, manufactured by Kawaguchi Electric Co., Ltd.).
8100) and charged so that the current flowing into the aluminum surface becomes 72 μA, and then exposure and static elimination are performed. The chargeability (V _o ) at that time, and the decrease in potential (dark) after leaving for 2 seconds from the start of charging (dark) Attenuation DD), half-life exposure sensitivity (E1 / 2 reference potential 500 V), and residual potential ( _Vr ) were measured. The results are shown in Table 1.

The coating solution for the charge generation layer and the charge transport layer prepared here was applied with a diameter of 30 mm, a length of 250 mm, and an inner thickness of 1 m.
m of an aluminum cylinder was sequentially applied by a dipping method to obtain a charge generation layer of 0.4 g / m ² and a charge transport layer of 21 g / m ² .
A μm drum-shaped photoreceptor was prepared. The photosensitive member was fixed to a surface tester (Haydon manufactured by Shinto Kagaku Co., Ltd.), and the edge of the cleaning blade used in a commercially available copying machine was circumferentially attached to the photosensitive member at an angle of 45 degrees. And apply a load of 50 g in the longitudinal direction of the photoreceptor.
The cleaning blade was moved at 0 mm / min, and the frictional force at that time was measured. The results are shown in Table 1.

Further, the photoreceptor was mounted on a copying machine having a blade cleaning member, and the amount of abrasion on the surface of the photoreceptor was measured when 100,000 copies were run, and the results are shown in Table 1.

Example 2 The same polycarbonate resin as used in Example 1 and 10 parts by weight of the same polycarbonate resin used in Example 1 and 90 parts by weight of a polycarbonate resin having the same weight of the structural units (a) and (B) were used. Except for Example 1
A photoreceptor was manufactured in the same manner as described above, and the electrical characteristics, frictional resistance, and wear amount were measured. The results are shown in Table 1.

Comparative Example 1 A photoconductor was produced in the same manner as in Example 1 except that a polycarbonate resin having the structural units (a) and (b) in an equal weight was used as a polycarbonate resin for a binder. The amount of wear was measured. The results are shown in Table 1.

[0058]

[Table 1] Table 1 ────────────────────────────────── Electrical characteristics Slip property Abrasion resistance V _o DD V _r E1 / 2 friction wear amount (V) (V) (V ) (luk / sec) (gw) (μm) ─────────────────── ─────────────── Example 1 1040 45 12 1.12 18 9.9 Example 2 1025 40 10 1.10 22 10.4 Comparative Example 1 1020 41 12 1.10 42 11.2 ──────── ──────────────────────────

As is evident from the results in Table 1, all the photoconductors using the copolymerized polycarbonate resin to which the polysiloxane of the present invention is grafted show good electrical properties equivalent to those of the comparative examples. In addition, as a result of the improvement of the surface slipperiness, it can be seen that even in a copy test using an actual machine, the amount of wear of the photosensitive layer is small and good wear resistance is exhibited.

Continuation of front page (56) References JP-A-2-240658 (JP, A) JP-A-4-234050 (JP, A) JP-A-4-163559 (JP, A) JP-A-61-219049 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 5/05 101 G03G 5/147 C08G 64/08 C08G 81/00 CA (STN)

Claims (2)

(57) [Claims] 1. An electrophotographic photosensitive member having at least a photosensitive layer on a conductive substrate, wherein the photosensitive layer comprises a charge generating substance,
An electrophotographic photoreceptor comprising a charge-transporting substance and a polycarbonate resin having a polysiloxane in a side chain, comprising a structural unit represented by the following general formula (1). Embedded image And R ₁ and R ₂ represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group, and Z represents a substituted or unsubstituted carbon ring having 4 to 20 carbon atoms. , Y ₁ to Y ₄ represent a polysiloxane group, a hydrogen atom, an allyl group, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group represented by the following general formula (2); _At least one of ₁ to Y ₄ is the polysiloxane group; In the general formula (2), R ₃ represents an alkylene group having 2 to 5 carbon atoms, R ₄ to R ₈ represent an alkyl group, an aryl group, or a fluoroalkyl group having 1 to 20 carbon atoms, and n represents 1 to 500
Indicates an integer. ) 2. The polysiloxane content of the side chain is from 0.01 to 2.
2. The electrophotographic photoreceptor according to claim 1, comprising 20% by weight of a polycarbonate resin.