JP2005099864A - Electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor ensuring few image defects, having high sensitivity and high durability, causing no degradation of image quality in actual copying on a large number of sheets, free of deterioration of sensitivity due to film wear and faulty cleaning, and excellent in lubricity and mechanical properties by using a coating liquid excellent in stability and nearly free of generation of bubbles therein. <P>SOLUTION: In the electrophotographic photoreceptor obtained by disposing a photosensitive layer on a conductive substrate, the photosensitive layer contains a copolymer comprising at least a repeating structural unit shown by formula [1-1] and a repeating structural unit shown by formula [1-5]. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photoconductor in the field of electrophotography, and relates to an organic electrophotographic photoconductor used by being incorporated in a copying machine or a printer.

  A description will be given of a copying machine based on the Carlson method, which is the most typical conventional electrophotographic method. After the photosensitive member is uniformly charged, the charge is erased imagewise by exposure to form an electrostatic latent image. This is developed and visualized with toner, and then the toner is transferred to a transfer body such as paper and fixed.

  On the other hand, the photoconductor is subjected to surface cleaning treatment such as removal of remaining adhered toner and charge removal, and is used repeatedly over a long period of time.

  Therefore, as an electrophotographic photoreceptor, the charging characteristics and sensitivity are good, and the dark decay is low. In addition to the electrophotographic characteristics, printing durability, abrasion resistance, and scratches on the surface are not easily scratched. It is required to have good physical properties such as resistance to ozone generated by corona discharge and durability to ultraviolet rays received during exposure, and these points are regarded as problems in practical use.

  Until now, so-called inorganic photoreceptors having an inorganic photoconductive substance such as selenium, zinc oxide, cadmium or the like as the main component of the photosensitive layer have been widely used as electrophotographic photoreceptors. However, these inorganic photoreceptors are often harmful and have problems in terms of environmental measures.

  Therefore, in recent years, organic photoreceptors using non-polluting organic substances have been actively developed and widely used. In particular, so-called function-separated type photoconductors have been actively developed in which a charge generation function and a charge transport function are assigned to different substances and compounds having desired characteristics can be selected from a wide range.

  However, such organic photoreceptors are generally inferior in mechanical strength to inorganic photoreceptors, and have problems such as abrasion and abrasion due to mechanical external forces such as a cleaning blade and a developing brush.

  For example, in a conventional photoreceptor in which a charge generation layer and a charge transport layer are sequentially laminated on a support, the charge transport layer is formed by binding a low molecular charge transport material with an inert polymer resin binder. Since the charge transport layer is generally soft, it is not always sufficient to achieve both mechanical characteristics and electrophotographic characteristics. With a highly sensitive composition or certain resin binders, a cleaning blade, etc. The surface of the photoconductor may be scratched or worn due to rubbing, etc., and the electrophotographic characteristics such as low wear or increased residual power can be satisfied with a highly wear-resistant composition or certain resin binders. There wasn't. This has become an obstacle to speeding up or downsizing of the Carlson process, which has been strongly oriented in recent years.

Regarding these problems, silicone-containing resins, fluorine-containing resins, and the like have been proposed for the charge transport layer as agents for reducing the coefficient of friction on the surface of the photoreceptor, reducing the surface energy, and reducing wear. However, they have low sensitivity, electrophotographic characteristics such as increased residual potential due to repeated use, and mechanical durability such as wear during repeated use, degradation in image quality due to scratches, and decreased sensitivity due to film wear. No resin that satisfies these requirements has been found. Furthermore, the stability of the coating solution is insufficient, the cloudiness and the viscosity change are large, and stable coating is difficult. In addition, the generation of bubbles in the coating solution is large, and there are many coating film defects and image defects (see, for example, Patent Documents 1 to 3).
JP-A-6-136108 JP-A-5-72753 JP-A-5-257298

  The object of the present invention is not only excellent in coating solution stability, but also less bubbles are generated in the coating solution, there are few image defects, and high sensitivity, high durability, deterioration of image quality when a large number of sheets are photographed, film depletion It is an object of the present invention to provide an electrophotographic photosensitive member that is excellent in lubricity and mechanical properties without causing a decrease in sensitivity or poor cleaning.

  In view of the present situation, the present inventors have of course made improvements in the slipperiness of the photoreceptor, and as a result of intensive studies on the stability of the coating solution, the photosensitive layer contains a specific copolymer polycarbonate. Thus, the present inventors have found that the slipperiness and durability can be improved without affecting other physical properties at all, that there is no image defect and that the coating solution stability is excellent, and the present invention has been completed.

That is, the object of the present invention is achieved by taking any of the following configurations.
(Claim 1)
In an electrophotographic photoreceptor having a photosensitive layer provided on a conductive substrate, the photosensitive layer has at least a repeating structural unit represented by the following general formula [1-1] and a repeating unit represented by the following general formula [1-5]. An electrophotographic photoreceptor comprising a copolymer having a structural unit.

Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl having 1 to 6 carbon atoms. Group, a cyclic hydrocarbon residue having 4 to 10 carbon atoms, and a substituted or unsubstituted aryl group.)

(R ₂₂ and R ₂₃ represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group, Z represents a substituted or unsubstituted carbocycle having 4 to 20 carbon atoms, P ₁ to P ₄ represent a polysiloxane group represented by the following general formula [1-6], 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, At least one of P ₁ to P ₄ is the polysiloxane group, R ₂₄ in the following general formula [1-6] represents an alkylene group having 2 to 5 carbon atoms, and R ₂₅ to R ₃₁ are carbon atoms. A 1-20 alkyl group, an aryl group, or a fluoroalkyl group, and n represents an integer of 1-500.)

(Claim 2)
The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer contains a charge transport material represented by the following general formula [1-8].

(However, in this general formula, R ₄₀ and R ₄₁ represent a substituted or unsubstituted alkyl group or aryl group, and the substituent is an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group. .

Ar ₁ and Ar ₂ represent a substituted or unsubstituted aryl group, and an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group is used as the substituent.

R ₄₂ and R _{43 each} represents a substituted or unsubstituted aryl group or a hydrogen atom, and an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group is used as the substituent. )
(Claim 3)
An electrophotographic photoreceptor having a photosensitive layer provided on a conductive substrate, wherein the photosensitive layer further contains a terpolymer having a repeating unit represented by the following general formula [1-9]. The electrophotographic photosensitive member according to claim 1.

(Wherein R ₄₄ , R ₄₅ , R ₄₆ , R ₄₇ , R ₄₈ , R ₄₉ , R ₅₀ or R ₅₁ each represents a hydrogen atom, a halogen atom or a lower alkyl group. N represents an integer of 2 or more. , Ra and Rb each represent a hydrogen atom, an alkyl group or an aryl group which may have a substituent, or Ra and Rb joined together to form a substituted or unsubstituted carbocyclic or heterocyclic ring. Represents the group to be formed.)
(Claim 4)
4. The electrophotographic photoreceptor according to claim 3, wherein the general formula [1-9] is represented by the following general formula [1-10].

( Wherein R _{52 to} R ₅₉ represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, or an aryl group. Z represents at least two or more substituted or unsubstituted groups. And a C 4-10 carbocyclic ring having an alkyl group, a cycloalkyl group, or an aryl group.)
(Claim 5)
The electrophotographic photoreceptor according to claim 1, 2, 3, or 4, wherein the photosensitive layer contains a polycarbonate represented by the general formula [1-9].

  According to the present invention, not only the coating solution stability is excellent, but also the generation of bubbles in the coating solution is small, the image defects are small, and the image quality at the time of shooting a large number of sheets with high sensitivity and high durability is deteriorated due to film depletion. It is possible to provide an electrophotographic photosensitive member which is excellent in lubricity and mechanical properties without causing a decrease in sensitivity or poor cleaning.

    The copolymer used in the present invention is a dihydric phenol represented by the general formula [1-1] ′ and

Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl having 1 to 6 carbon atoms. Group, a cyclic hydrocarbon residue having 4 to 10 carbon atoms, and a substituted or unsubstituted aryl group.)
A silicon atom-containing dihydric phenol represented by the general formula [1-2] ′, [1-4] ′, [1-5] ′ or [1-7] ′ and phosgene, carbonate ester, or chloroformate Are copolymerized to produce the general formulas [1-1] and [1-2], [1-1] and [1-4], [1-1] and [1-5] or [1-1]. And a polycarbonate copolymer such as [1-7].

  Examples of the corresponding polycarbonate corresponding to the homopolymer or the monomer as the third copolymerization component are described in, for example, JP-A-51-88226, specifications 14 to 16p.

(Wherein R ₉ , R ₁₀ , R ₁₁ and R ₁₂ each represent a hydrogen atom, an alkyl group, an aryl group or a halogen atom, and R ₁₃ and R ₁₄ each represent a hydrogen atom, an alkyl group or an aryl group. .)

(Wherein R ₁₇ is an alkylene group or alkylidene group having 2 to 6 carbon atoms, R _{18 to} R ₂₁ are alkyl groups having 1 to 3 carbon atoms, phenyl group or substituted phenyl, substituted or unsubstituted cycloalkyl group, n Represents 1 to 200.)

Wherein R ₂₂ and R ₂₃ 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 Q represents a substituted or unsubstituted carbocycle having 4 to 20 carbon atoms. P ₁ to P ₄ are a polysiloxane group represented by the following general formula [1-6] ′, a hydrogen atom, an allyl group, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group, or an alkyl halide. And at least one of P ₁ to P ₄ is the polysiloxane group, R ₂₄ in the following general formula [1-6] ′ represents an alkylene group having 2 to 5 carbon atoms, R ₂₅ to R ₃₁ represents an alkyl group having 1 to 20 carbon atoms, an aryl group, or a fluoroalkyl group, and n represents an integer of 1 to 500.)

(Wherein, X represents an alkylene group, R ₃₂ , R ₃₃ and R ₃₄ each independently represents an optionally substituted alkyl group or aryl group, and R ₃₅ has 1 to 15 carbon atoms.) R ₃₆ , R ₃₇ , R ₃₈ and R ₃₉ each independently represents a hydrogen atom, an alkyl group or a halogen atom, and m and n are 0 or a positive integer.)
Methods for synthesizing these monomers are described in detail in JP-A-2-236555, JP-A-4-268369, JP-A-5-158249, and the like.

  Specific monomers are shown below.

  Specific polymer examples are as follows.

  Various configurations of the photoreceptor are known.

  The present invention can take any of these forms of the photoreceptor, but it is desirable to use a laminated or dispersed function separation type photoreceptor. In this case, normally, it becomes a structure as shown to Fig.1 (a)-(f). The layer structure shown in FIG. 1 (a) is such that a carrier generation layer 2 is formed on a conductive support 1, and a carrier transport layer 3 is laminated thereon to form a photosensitive layer 4, and FIG. ) Is a photosensitive layer 4 ′ in which the carrier generation layer 2 and the carrier transport layer 3 are reversed. FIG. 4C shows an intermediate layer 5 provided between the photosensitive layer 4 having the layer structure of FIG. 5A and the conductive support 1, and FIG. 4D shows the conductive layer 4 ′ having the layer structure of FIG. An intermediate layer 5 is provided between the conductive support 1 and the intermediate support 5. The layer structure of FIG. 5E is a structure in which a photosensitive layer 4 ″ containing a carrier generating material 6 and a carrier transporting material 7 is formed. FIG. 8F shows such a photosensitive layer 4 ″ and a conductive support. 1 is provided with an intermediate layer 5. In the configurations of FIGS. 1A to 1F, a protective layer may be further provided on the outermost layer.

  The negatively charged photoreceptor is preferably the type (c), and the positively charged photoreceptor is preferably (b) or (f). Further, a plurality of charge transport layers may be provided to improve durability and sensitivity.

  In the present invention, the photosensitive layer means each layer on the support of the photosensitive member, and thus the protective layer is included in this category.

  The binder of the present invention is preferably used for forming the charge generation layer 2, the charge transport layer 3 or the protective layer, and any mixture can be used as long as it has good miscibility. It is preferable to use an electrically insulating film-forming polymer. Examples of such a high molecular polymer include the following.

Polycarbonate Polyester Methacrylic acid Acrylic resin Polyvinyl chloride Polyvinylidene chloride Polystyrene Polyvinyl acetate Styrene-butadiene copolymer Vinylidene chloride-acrylonitrile copolymer Vinyl chloride-vinyl acetate copolymer Vinyl chloride-vinyl acetate-maleic anhydride copolymer Silicone resin Silicone-alkyd resin Phenol-formaldehyde resin Styrene-alkyd resin Poly-N-vinylcarbazole Polyamide Polyurethane Polyketone Epoxy resin Polyvinyl butyral Polyvinyl formal The polycarbonate copolymer of the present invention is used for fine adjustment of physical properties and coating properties as required. A mixture with other polycarbonates may also be used. The mixing ratio of other polycarbonates varies depending on the silicon atom-containing monomer unit length, polysiloxane chain length, and content, but is preferably 0 to 95%, and preferably 5 to 80%.

  In the present invention, the charge generation layer is coated with a dispersion obtained by dispersing the charge generation material alone or together with an appropriate binder resin on a conductive support or an intermediate layer as required, and then dried. It can form by the method of making it, a vacuum evaporation method, etc.

In the photoreceptor of the present invention, a pigment as shown in the following representative example is used as a charge generating material.
(1) Azo pigments such as monoazo pigments, bisazo pigments, triazo pigments, metal complex azo pigments (2) Perylene pigments such as perylene acid anhydride and perylene imide (3) Anthraquine derivatives, anthanthrone derivatives, dibenzpyrenequinone derivatives Polycyclic quinone pigments such as pyranthrone derivatives, violanthrone derivatives and isoviolanthrone derivatives (4) indigoid pigments such as indigo derivatives and thioindigo derivatives (5) phthalocyanine pigments such as metal phthalocyanines and metal-free phthalocyanines Examples thereof include dibromoanthanthrone pigments, bisimidazopyridonoperylene, and Y-type titanyl phthalocyanines described in Japanese Patent Application No. 62-173640.

  In the present invention, a ball mill, an attritor, a sand grinder or the like is used for dispersing the charge generating material.

  In the charge generation layer formed as described above, the mass ratio between the charge generation material and the binder is preferably 100: 0 to 1000. If the content ratio of the charge generation material is less than this, the photosensitivity is low, resulting in an increase in the residual potential.

  When the charge generation material is contained in the charge generation layer, the ratio of the charge generation material to the charge transport material is preferably 10: 0 to 10: 1000, particularly preferably 10: 0, in mass ratio. 10: 100.

  The charge generation layer can be applied by dip coating, spray coating, blade coating, roll coating or the like.

  The thickness of the charge generation layer to be formed is preferably 0.01 to 10 μm.

  In the present invention, an intermediate layer may be provided between the conductive support and the charge generation layer, and the thickness of the intermediate layer is 0.01 to 15 μm. Preferably it is set as the range of 0.05-3 micrometers. If the thickness is less than 0.01 μm, the injection of charges from the support to the photosensitive layer cannot be prevented. Also, pinholes are likely to occur in the photoreceptor due to the unevenness of the support. If the thickness exceeds 15 μm, the residual potential of the photosensitive layer cannot be effectively removed.

  Further, as the binder used for the intermediate layer, an arbitrary one is selected in consideration of electrical resistance, environmental resistance, adhesion with other layers, insolubility in the solvent of other layers, and the like.

  These solvents can be used alone or as a mixed solvent of two or more.

  As a method for forming the intermediate layer, a resin is dissolved in a solvent, and dip coating, spray coating, bead coating, or the like may be used.

  Next, the charge transport layer used in the present invention will be described.

  In the present invention, the charge transport layer is formed by a method in which a solution or dispersion obtained by dissolving and dispersing the charge transport material and the binder resin of the present invention in a solvent is applied onto the charge generation layer and dried. Can do.

  In the photoreceptor of the present invention, pyrazoline compounds, hydrazone compounds, stilbene compounds, triphenylamine compounds, benzidine compounds, oxazole compounds, indole compounds, carbazole compounds, and the like are used as the charge transport material.

  In more detail, the charge transporting material preferably used in the present invention is preferably a compound represented by the general formulas [II] to [X] described in Japanese Patent Application No. 5-240801. Specific examples of the compounds are described in pages 58 to 64 of the above Japanese Patent Application No. 5-240801.

  Examples of the conductive support 1 used in the photoconductor according to the present invention include a metal plate including an alloy, a metal drum or a conductive polymer, a conductive compound such as indium oxide, and an aluminum including an alloy, palladium, gold, and the like. Examples thereof include paper, plastic film and the like which are made conductive by applying, evaporating or laminating a thin metal layer. As the intermediate layer 5 such as an adhesive layer or a barrier layer, an organic polymer substance such as polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, polyamide, or aluminum oxide is used in addition to the polymer used as the binder resin.

  In the photoreceptor according to the present invention, for the purpose of improving the charge generation function of the charge generation material, an organic amine described in, for example, Japanese Patent Application Laid-Open No. 60-172044 is included in the photosensitive layer 4 in an amount of 1 or less. Preferably, it can be contained in an amount of 0.2 to 0.005 times. For the purpose of improving sensitivity and reducing residual potential or fatigue during repeated use, the electron-accepting material described in the above publication is contained in the charge generating layer 2 in an amount of 0.01 to 200 parts by weight, preferably 0.1 to 100 parts by weight of the charge generating substance. -100 mass parts can be contained.

  The polycarbonate copolymer resin containing silicon atoms or the polycarbonate resin having polysiloxane in the side chain used in the present invention is used by adding to the photosensitive layer, but particularly when used as a binder resin for the charge transport layer. Is effective. The proportion of the charge transfer agent in that case is 30 to 300 parts by weight, preferably 40 to 200 parts by weight, more preferably 40 to 150 parts by weight based on 100 parts by weight of the polycarbonate polymer or copolymer resin having a silicon atom of the present invention. Used in the range of parts by mass. Moreover, as another usage pattern, it may be used for the uppermost layer such as a protective layer.

  The charge transport layer may contain various additives such as an antioxidant and a sensitizer as necessary. The charge transport layer may be used in a thickness of 10 to 60 μm, preferably 10 to 45 μm. In the case of the dispersion type photosensitive layer, the above-mentioned charge generating material is dispersed in the charge transport medium having the above-mentioned blending ratio containing the polycarbonate polymer or copolymer resin of the present invention. In that case, the particle size needs to be sufficiently small, and is preferably 1 μm or less, more preferably 0.5 μm or less. If the amount of the charge generating material dispersed in the photosensitive layer is too small, sufficient sensitivity cannot be obtained, and if it is too large, there are adverse effects such as a decrease in chargeability and a decrease in sensitivity, for example, preferably 0.5 to 50% by mass. It is used in a range, more preferably in a range of 1 to 20% by mass. The film thickness of the photosensitive layer is usually 5 to 50 μm, more preferably 10 to 45 μm. In this case as well, known plasticizers for improving film formability, flexibility, mechanical strength, additives for suppressing residual potential, dispersion aids for improving dispersion stability, coatability A repelling agent and a surfactant, for example, silicone oil, fluorine-based oil and other additives may be included for improving the resistance.

Examples of the present invention will be specifically described below, but the present invention is not limited thereto.
Laminated photoreceptor sample 1-1
30 g of polyamide resin CM-8000 (manufactured by Toray Industries, Inc.) was charged into a mixed solution of 900 ml of methanol and 100 ml of 1-butanol, and heated and dissolved at 50 ° C. This solution was dip-coated on an aluminum drum substrate having an outer diameter of 80 mm and 355.5 mm to form a 0.3 μm intermediate layer.

  Next, 10 g of polyvinyl butyral resin ESREC BL-S (manufactured by Sekisui Chemical Co., Ltd.) was dissolved in 1000 ml of methyl ethyl ketone, 30 g of the exemplified compound (CGM-1) was mixed as CGM, and dispersed for 20 hours using a sand mill. Using this solution, dip coating was performed on the intermediate layer to form 0.5 μm thick CGL.

  Next, 150 g of exemplified compound CTM-1 as CTM and 200 g of exemplified compound (P-1-2-1) as CTL binder were dissolved in 1,000 ml of 1,2-dichloroethane.

  Using this solution, dip coating was performed on the CGL, followed by drying at 100 ° C. for 60 minutes to form a CTL having an average film thickness of 21 μm.

In this way, a laminated photoreceptor sample 1-1 comprising the intermediate layer, CGL, and CTL was obtained. (For Example 1-1)
Laminated photoreceptor samples 1-2 and 1-3
In the photoreceptor sample 1-1, laminated photoreceptor samples 1-2 and 1-3 were obtained in the same manner except that the CTL binder shown in Table 1 was used. (For Examples 1-2 and 1-3)
Laminated photoreceptor sample 1-4
15 g of polyamide resin racamide 5003 (manufactured by Dainippon Ink & Co., Ltd.) was put into a mixed solution of 800 ml of methanol and 200 ml of 1-butanol, and heated and dissolved at 50 ° C. This solution was dip coated on an aluminum drum substrate having an outer diameter of 80 mm and 355.5 mm to form a 0.5 μm intermediate layer.

  Next, 10 g of silicone resin KR-5240 (solid content 20%) (manufactured by Shin-Etsu Chemical Co., Ltd.) is dissolved in a mixed solvent of 700 ml of methyl ethyl ketone and 300 ml of cyclohexanone. And dispersed for 20 hours using a sand mill. This solution was dip-coated on the intermediate layer to form a 1.0 μm thick charge generation layer.

  Next, 150 g of exemplary compound (CTM-2) as CTM and 150 g of exemplary compound (P-1-4-1) as a charge transport layer binder were dissolved in 1000 ml of 1,2-dichloroethane.

  Using this solution, dip coating was performed on the charge generation layer, followed by drying at 100 ° C. for 60 minutes to form a charge transport layer having an average film thickness of 20 μm.

In this way, a laminated photoreceptor sample 1-4 comprising an intermediate layer, a charge generation layer, and a charge transport layer was obtained.
Laminated photoreceptor sample 1-5 to 1-9
Laminated photoreceptor samples 1-5 to 1-9 were obtained in the same manner except that the charge transport layer binder shown in Table 1 was used in the laminated photoreceptor sample 1-4. (For Examples 1-5 to 1-9)
Laminated photoreceptor sample 1-10
The process until the formation of the intermediate layer was performed in the same manner as for the photoreceptor sample 1-1.

  Next, 2.5 g of polyvinyl butyral resin ESREC BX-1 (manufactured by Sekisui Chemical Co., Ltd.) is dissolved in 1000 ml of methyl isobutyl ketone, and 10 g of the exemplified compound (CGM-3) is mixed therein as a charge generating substance. Time dispersed. Using this solution, the charge generation layer having a thickness of 0.5 μm was formed by dip coating on the intermediate layer.

  Next, a charge transport layer was formed in the same manner as in the photoreceptor sample 1-4 except that the exemplified compound (P-1-7-1) was used as the charge transport layer binder and CTM-3 was used as the CTM.

Thus, a laminated photoreceptor sample 1-10 composed of an intermediate layer, a charge generation layer, and a charge transport layer was obtained. (For Example 1-10)
Laminated photoreceptor 1-11 to 1-13
Laminated photoreceptor samples 1-11 to 13 were obtained in the same manner as in laminated photoreceptor sample 1-9, except that the charge transport layer binder shown in Table 1 was used. (For Examples 1-11 to 13)
Laminated photoreceptor sample 1-14
A laminated photoreceptor sample 1-14 was obtained in the same manner except that the CTL binder was changed to C-1-1 in the laminated photoreceptor sample 1-1. (For Comparative Example 1-1)
Laminated photoreceptor samples 1-15 and 1-16
Laminated photoreceptor samples 1-15 and 16 were obtained in the same manner except that the CTL binder in the laminated photoreceptor sample 1-4 was changed to C-1-2 and C-1-3, respectively. (For Comparative Examples 1-2 and 1-3)
Laminated photoreceptor sample 1-17
A laminated photoreceptor sample 1-17 was obtained in the same manner except that the CTL binder was changed to C-1-4 in the laminated photoreceptor sample 1-10. (For Comparative Example 1-4)
Laminated photoreceptor sample 1-18
A laminated photoreceptor sample 1-18 was obtained in the same manner except that 75 g each of C-1-2 and BPZ were used in the laminated photoreceptor sample 1-2. (For Comparative Example 1-5)
Examples 1-1 to 1-13 and Comparative Examples 1-1 to 1-5
-Evaluation of photoconductor-
Laminated photoconductor samples 1-1 to 1-18 were mounted on “U-Bix4045” (manufactured by Konica), and a live-action test of 100,000 copies was performed. The initial image was observed and the thickness loss after 100,000 copies was investigated.
-Evaluation of coating solution-
Each CTL solution used was observed for turbidity when left at 20 ° C. for 1 month. The case where there was turbidity was marked as x, and the case where there was no turbidity was marked as ◯. Further, the viscosity immediately after adjustment and the viscosity after standing for 1 week were measured using a B-type viscometer. (Under 23 ℃)
Vis ratio = viscosity after 1 week / viscosity immediately after preparation

-Evaluation of photoreceptor surface-
Each of the obtained photoreceptors was visually observed on the surface of the photoreceptor.

○ 2 or less per bubble failure
△ 3-10 per bubble failure
× 11 or more per bubble failure The practical level is ○ class. According to the live-action test, it is clear that image defects are often caused by bubble failures.

  The above results are shown in Table 1.

  From the results shown in Table 1, it can be seen that the photoreceptor of the present invention is stable with little change over time in the coating solution. In addition, it can be seen that the image quality is stable even during actual shooting and the image quality is stable over a long period of time because of less film wear.

  The same result was obtained when a single layer was used.

FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conductive support body 2 Carrier generation layer 3 Carrier transport layer 4 Photosensitive layer 5 Intermediate layer

Claims (5)

In an electrophotographic photoreceptor having a photosensitive layer provided on a conductive substrate, the photosensitive layer has at least a repeating structural unit represented by the following general formula [1-1] and a repeating unit represented by the following general formula [1-5]. An electrophotographic photoreceptor comprising a copolymer having a structural unit.

Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl having 1 to 6 carbon atoms. Group, a cyclic hydrocarbon residue having 4 to 10 carbon atoms, and a substituted or unsubstituted aryl group.)

(R ₂₂ and R ₂₃ represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group or a halogenated alkyl group, Z represents a substituted or unsubstituted carbocycle having 4 to 20 carbon atoms, P ₁ to P ₄ represent a polysiloxane group represented by the following general formula [1-6], 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, At least one of P ₁ to P ₄ is the polysiloxane group, R ₂₄ in the following general formula [1-6] represents an alkylene group having 2 to 5 carbon atoms, and R ₂₅ to R ₃₁ are carbon atoms. A 1-20 alkyl group, an aryl group, or a fluoroalkyl group, and n represents an integer of 1-500.)

The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer contains a charge transport material represented by the following general formula [1-8].

(However, in this general formula, R ₄₀ and R ₄₁ represent a substituted or unsubstituted alkyl group or aryl group, and the substituent is an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group. .
Ar ₁ and Ar ₂ represent a substituted or unsubstituted aryl group, and an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group is used as the substituent.
R ₄₂ and R _{43 each} represents a substituted or unsubstituted aryl group or a hydrogen atom, and an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group is used as the substituent. ) An electrophotographic photoreceptor having a photosensitive layer provided on a conductive substrate, wherein the photosensitive layer further contains a terpolymer having a repeating unit represented by the following general formula [1-9]. The electrophotographic photosensitive member according to claim 1.

(Wherein R ₄₄ , R ₄₅ , R ₄₆ , R ₄₇ , R ₄₈ , R ₄₉ , R ₅₀ or R ₅₁ each represents a hydrogen atom, a halogen atom or a lower alkyl group. N represents an integer of 2 or more. , Ra and Rb each represent a hydrogen atom, an alkyl group or an aryl group which may have a substituent, or Ra and Rb joined together to form a substituted or unsubstituted carbocyclic or heterocyclic ring. Represents the group to be formed.) 4. The electrophotographic photoreceptor according to claim 3, wherein the general formula [1-9] is represented by the following general formula [1-10].

( Wherein R _{52 to} R ₅₉ represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, or an aryl group. Z represents at least two or more substituted or unsubstituted groups. And a C 4-10 carbocyclic ring having an alkyl group, a cycloalkyl group, or an aryl group.) The electrophotographic photoreceptor according to claim 1, 2, 3, or 4, wherein the photosensitive layer contains a polycarbonate represented by the general formula [1-9].

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