JPH05165244A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body which maintains high sensitivity for repeated use and good wear resistance and is reduced in scratches or wearing on its surface due to cleaning brushs or cleaning blades without causing problems such as cleaning failure of a developer. CONSTITUTION:The device for formation of picture images has a cleaning means in which a cleaning blade is brought into contact with a photosensitive body in the counter direction to the rotation direction of the photosensitive body. The coefft. of surface friction of this photosensitive body in the device is specified to <=1.5 [-] or lower, more preferably, <=1.0 [-]. The coefft. of surface friction is obtd. from the measurement with the cleaning blade brought into contact with the photosensitive body on which a thin layer of the developer is applied. More preferably, a silicone oil is incorporated into the outermost surface layer of the photosensitive body by 0.05-5wt.% to the binder resin, or more preferably, 0.05-5wt.% of the silicone oil and 0.5-2wt.% of fluorine-base surfactant are incorporated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member used when an image is formed by an electrophotographic process such as a copying machine or a printer.

[0002]

2. Description of the Related Art In recent years, electrophotographic photoconductors using organic photosensitive materials, which have advantages such as low cost, productivity, and no pollution, have become popular. Organic electrophotographic photoreceptors include a photoconductive resin typified by polyvinylcarbazole (PVK), a charge transfer complex typified by PKV-TNF (2,4,7-trinitrofluorenone), and a phthalocyanine-binder. A pigment-dispersed photoconductor, which is a typical example, and a function-separated photoconductor, which uses a combination of a charge generation substance and a charge transfer substance, has been receiving attention. When such a function-separated high-sensitivity photoconductor is used in a Carlson type copying machine or printer, after charging the photoconductor surface, the electrostatic latent image is developed by charged colored powder (toner) by exposure. Then, the visible image is transferred and fixed on paper or the like. At the same time, the photosensitive member is subjected to removal of adhered toner, charge removal, and surface cleaning (cleaning), and is repeatedly used for a long time.

Therefore, the electrophotographic photosensitive member has, of course, electrophotographic characteristics such as good chargeability and sensitivity and small dark decay, but in addition, abrasion resistance and abrasion resistance in repeated use. It is also required to be stable in mechanical durability, humidity resistance, and resistance to alteration by ultraviolet rays in corona discharge light emission.

However, in a conventional electrophotographic photoreceptor in which a charge generation layer and a charge transfer layer are sequentially laminated on a support, the charge transfer layer is formed by binding a low molecular weight charge transfer material with a polymer resin binder. Since it is formed, it is not always sufficient to make the mechanical strength characteristics and the electrophotographic characteristics compatible with each other, and with a composition having a high sensitivity or a resin binder type, it is possible to rub the cleaning brush and / or the cleaning blade during repeated use of the photoreceptor. However, electrophotographic characteristics such as scratches on the surface of the photoconductor and abrasion of the surface, low sensitivity with a composition having high abrasion resistance or resin binder species, and increased residual potential were not satisfied.

With respect to the above-mentioned drawbacks, for example, JP-A-59-59
In JP 7955-61 and JP 61-17945, a charge transfer material is prepared by using a silicone resin and a polycarbonate resin having dimethylpolysiloxane in order to improve the occurrence of scratches on the outermost surface charge transfer layer (CTL-2). (C
Spray coating with a solvent that can dissolve TM). In JP-A-60-12551, in order to improve scratch generation due to friction and corona resistance of CTM, the CTL is multi-layered and the CTM content in the deepest charge transfer layer (CTL-1) is CT.
It is more than L-2. JP-A-60-12552 discloses a thermoplastic polyester carbonate single layer or CGM or CT between CGL and CTL in order to improve adhesion between the charge generation layer (CGL) and CTL.
An intermediate layer of thermosetting polyester carbonate with M added is provided. In JP-A-60-87331 and JP-A-60-143346, the CTL is divided into two layers through a charge transferable intermediate layer in order to improve scratch generation due to friction and corona resistance of CTM. CTL-2 C
TM / R is made smaller than CTL-1. JP-A-6
In JP-A 2-272228, in order to improve wear resistance, C
A protective layer made of CTM (hydrazone compound) which is good for polycarbonate resin and polytetrafluoroethylene is provided on the TL. In Japanese Patent Application Laid-Open No. 2-160247, the CTL-1 CTM / R is CT-multilayered in order to improve the mechanical strength and the penetration of ozone into the photosensitive layer.
It is larger than that of L-2, and the resin binder of CTL-2 uses a specific polycarbonate. JP-A-2
In JP-A-161449, a protective layer containing polyetherimide as a main component is provided to improve durability. In JP-A-2-178672, an intermediate compound is provided between CTL and CGL to promote separation and injection of carriers by containing an amine compound in order to have a low residual potential in repeated use and high sensitivity. Photoconductors, etc. were proposed. These proposals do not fully satisfy both sensitivity and durability, and in recent years, there has been an increasing demand for durability while maintaining high sensitivity.

Further, when the photosensitive member is repeatedly used, scratches and abrasions on the surface of the photosensitive member due to rubbing of the cleaning brush and the cleaning blade cause the material and shape of the cleaning blade and the cleaning brush, the contact condition with the photosensitive member surface, and the like. In relation to the cleaning of the photosensitive member, there is a report relating to prevention of defective cleaning of the developer (for example, the surface of the electrophotographic photosensitive member is roughened in JP-A-60-263956, JP-A-2-101488). Fine powder is interposed between the cleaning blade and the photoconductor.
In many cases, a thin portion is provided at the end portion of the cleaning blade of JP-A-162388, and a fluorine-containing compound is contained in the photosensitive layer and the protective layer of JP-A-57-82842 and JP-A-62-272228. On the other hand, there are few reports on reduction of scratches and wear on the surface of the photoconductor due to rubbing of a cleaning brush or a cleaning blade during repeated use of the photoconductor (for example, bisphenyl Z having a specific molecular weight disclosed in JP-A-3-20768). (For example, cleaning an electrophotographic photosensitive member having a type polycarbonate with a cleaning blade having a specific shape and material) has not been sufficiently satisfied.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and a first object thereof is to provide an electronic device which maintains high sensitivity even after repeated use and has good wear resistance. To provide a photographic photoreceptor. A second object is to provide an electrophotographic photoconductor in which scratches and abrasion of the photoconductor surface due to rubbing of a cleaning brush or a cleaning blade are reduced without causing defects such as poor cleaning of the developer even after repeated use. Especially.

[0008]

According to the present invention, there is provided an electrophotographic photosensitive member for use in an image forming apparatus having a cleaning unit in which a cleaning blade is brought into contact with the rotating direction of the electrophotographic photosensitive member in a counter direction. An electrophotographic photosensitive member is provided in which the surface friction coefficient (μ) of the electrophotographic photosensitive member is 1.5 [−] or less.

Generally, in the cleaning method in which the cleaning blade is brought into contact with the electrophotographic photosensitive member in the training direction with respect to the rotation direction of the photosensitive member, a cleaning blade having a large hardness is used to prevent defective cleaning of the developer. To be done. For this reason, it becomes necessary to increase the contact pressure of the cleaning blade on the electrophotographic photosensitive member, and the amount of abrasion of the electrophotographic photosensitive member increases during repeated use. Therefore, the method of cleaning the electrophotographic photosensitive member by bringing the cleaning blade into contact with the electrophotographic photosensitive member in the counter direction with respect to the rotation direction of the electrophotographic photosensitive member is more advantageous in terms of abrasion resistance, but the present inventor According to these studies, the surface friction coefficient of the outermost surface layer of the electrophotographic photosensitive member is 1.5.
It has been found that when the value exceeds [-], inconveniences such as inversion of the cleaning blade and chattering occur. Therefore, the electrophotographic photoreceptor of the present invention has an outermost surface layer having a surface friction coefficient of 1.5 [-].
It is characterized in that it is preferably 1.0 [-] or less. Further, in the present invention, it is desirable that the contact angle of the cleaning blade with the electrophotographic photosensitive member is set to 5 ° to 50 °, preferably 10 ° to 30 °. The surface friction coefficient here is a value measured by providing a thin layer of a developer on the electrophotographic photosensitive member and then bringing the cleaning blade into contact therewith.

The material of the cleaning blade used in the present invention is urethane resin, and the impact resilience is 30% to 30%.
70% is preferable, and hardness is preferably 60 ° to 80 °. The contact pressure on the electrophotographic photosensitive member is 5 to 50 g / c.
It is more preferably 10 to 30 g / cm than m, and further preferably a plate-like shape which has been subjected to a treatment such as providing a thin portion at the end if necessary.

In the electrophotographic photosensitive member of the present invention, preferably, silicon oil is added to the outermost surface layer in an amount of 0.
05 to 5% (weight ratio), preferably 0.1 to 2% (weight ratio). With such a structure, an electrophotographic photosensitive member having a surface friction coefficient of the outermost surface layer (1.5 [-] or less) can be easily obtained. Due to the compatibility with the charge transfer material and the binder resin, the silicone oil is clouded when the content of silicon oil exceeds 5% (weight ratio) with respect to the binder resin. If it is less than 0.05% (weight ratio) with respect to the binder resin, the effect of reducing the surface friction coefficient can be obtained.

Examples of the silicone oil used in the present invention include those represented by the following general formula. In the formula, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each an alkyl group such as methyl or ethyl, phenyl,
It represents an aryl group such as naphthyl or an alkoxy group such as methoxy and ethoxy, and may be substituted with another substituent or a halogen atom. n is a positive integer. Specific examples of these include dimethyl silicone oil,
Examples include methyl-phenyl silicone oil and dimethyldiphenyl copolymer silicone oil. Further, in the present invention, the outermost surface layer may contain both silicone oil and a fluorosurfactant. Fluorine-based surfactants by themselves do not have much effect of reducing the surface friction coefficient and have poor compatibility with charge transfer substances and binder resins as compared with silicone oils, so only a very small amount can be added. However, if both are used together, a large effect of reducing the surface friction coefficient can be obtained.

The fluorine-containing surfactant used in the present invention is preferably an oligomer having a perfluoroalkyl group having 2 to 10 carbon atoms in its main chain or side chain and having a molecular weight of 1,000 to 10,000. Commercially available products include Modiper (Nippon Yushi), Surflon (Asahi Glass), and Defencer (Dainippon Ink and Chemicals). The addition amount is 0.05 to 2% (weight ratio) with respect to the binder resin, preferably 0.1 to 1%. If the content is more than 2% (weight ratio) with respect to the binder resin, the coating liquid becomes cloudy due to the compatibility with the charge transfer substance and the binder resin. If it is less than 0.05% (weight ratio) with respect to the binder resin, the effect of reducing the surface friction coefficient cannot be obtained.

The dielectric support has a volume resistance of 10 ¹⁰
Those exhibiting inductivity of Ωcm or less, for example, metals and alloys such as aluminum, titanium, nickel, chromium, nichrome, hastelloy, palladium, magnesium, zinc, copper, gold and platinum, tin oxide, indium oxide, antimony oxide and the like. A film or cylindrical plastic, paper or the like coated with a metal oxide by vapor deposition, sputtering, or dispersion in a resin binder and coating, a film of the above metal or metal oxide or dielectric carbon. Or a plate of aluminum, an aluminum alloy, iron, nickel, a nickel alloy, a stainless alloy, a titanium alloy, etc., which are dispersed and contained in a cylindrical or cylindrical plastic, and D. I. , I. I. It is possible to use a tube or the like which has been subjected to surface treatment by cutting, superfinishing, polishing or the like after forming a raw tube by a method such as extrusion or drawing.

The charge generation layer is composed of only the charge generation material or a resin layer in which the charge generation material is dispersed or compatible.

As the charge generating material, for example, CI Pigment Blue 25 [Color Index (CI) 21
180], CI Pigment Red 41 (CI 21
200), CI Acid Red 52 (CI 4510
0), CI Basic Red 3 (CI 4521
0), and further, a phthalocyanine-based pigment having a porphyrin skeleton, an azurenium salt pigment, a squalic salt pigment,
Azo pigments having a carbazole skeleton (JP-A-53-95)
No. 033), an azo pigment having a stilstilbene skeleton (described in JP-A-53-138229), and an azo pigment having a triphenylamine skeleton (JP-A-53-53).
No. 132547), an azo pigment having a dibenzothiophene skeleton (described in JP-A No. 54-21728), an azo pigment having an oxadiazole skeleton (JP-A No.
4-12742), an azo pigment having a fluorenone skeleton (described in JP-A-54-22834),
Azo pigments having a bisstilbene skeleton (JP-A-54-1)
7733), an azo pigment having a distyryl oxadiazole skeleton (described in JP-A-54-2129), an azo pigment having a distyryl carbazole skeleton.
(Described in JP-A-54-17734), triazo pigment having a carbazole skeleton (JP-A-57-195767).
No. 57-195768) and CI Pigment Blue 16 (CI 7410).
0) etc., phthalocyanine-based pigments, CI BAT Brown 5 (CI 73410), CI BAT Die (CI
73030) and other indigo pigments, Argos Scarlet B (manufactured by Violet), Induslen Scarlet R
Organic pigments such as perylene pigments (such as Bayer Co.) can be used. Among these charge generating materials, azo pigments are particularly preferable, and among the azo pigments, disazo pigments and trisazo pigments shown below are most preferable. Specific examples of the azo pigment are shown below. In the table, A ₁ , A ₂ and A ₃ may be the same or different.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

[Table 4]

[0021]

[Table 5]

[0022]

[Table 6]

[0023]

[Table 7]

[0024]

[Table 8]

[0025]

[Table 9]

[0026]

[Table 10]

[0027]

[Table 11]

[0028]

[Table 12]

[0029]

[Table 13]

[0030]

[Table 14]

[0031]

[Table 15] The film thickness of the charge generation layer is suitably about 0.05 to 2 μm, preferably 0.1 to 1 μm. For the charge generation layer, the charge generation material is dispersed or compatible with a resin binder in an appropriate solvent, and this is applied onto the substrate or the undercoating phase.
It is formed by drying. Examples of such a resin binder include polystyrene, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, polyester, polyarylate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. Coalesce, polyvinyl acetate, polyvinylidene chloride, polyacrylate, polycarbonate, cellulose acetate resin,
Ethyl cellulose resin, polyvinyl butyral, polyvinyl acetal, polyvinyl formal, phenoxy resin, polyvinyl pyridine, poly-N-vinyl carbazole, acrylic resin, silicone resin, nitrile rubber, chloroprene rubber, butadiene rubber, epoxy resin, melamine resin, urethane resin, phenol Thermoplastic or thermosetting resins such as resins and alkyd resins can be mentioned. These binder materials may be used alone or as a mixture.
As the solvent, benzene, toluene, xylene, methylene chloride, dichloroethane, monochlorobenzene, dichlorobenzene, ethyl alcohol, methyl alcohol, butyl alcohol, isopropyl alcohol, ethyl acetate, butyl acetate, methyl ethyl ketone, dioxane, tetrahydrofuran, cyclohexane, methyl cellosolve. , Ethyl cellosolve, etc., and these solvents can be used alone or in combination.

Examples of the electron transfer material used in the present invention include poly-N-arbazole and its derivative, poly-γ-carbazolylethylglutamate and its derivative, pyrene-formaldehyde condensate and its derivative, polyvinylpyrene, polyvinylphenanthrene, There are oxazole derivatives, imidazole derivatives, triphenylamine derivatives, and compounds represented by the following formula. (1) (JP-A-55-154955, JP-A-1569)
(Described in No. 54)

[Chemical 1] [In the formula, R ₁ represents a methyl group, an ethyl group, a 2-hydroxyethyl group or a 2-chloroethyl group, R ₂ represents a methyl group, an ethyl group, a benzyl group or a phenyl group, and R 2
₃ represents hydrogen, chlorine, bromine, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, a dialkylamino group or a nitro group. (2) (described in JP-A-55-52063)

[Chemical 2] [In the formula, Ar represents a naphthalene group, anthracene group, a styryl group and a substitution product thereof, or a pyridine group, a furan group, and a thiophene group, and R represents an alkyl group or a benzyl group. (3) (described in JP-A-56-81850)

[Chemical 3] [In the formula, R ₁ is an alkyl group, a benzyl group, a phenyl group,
Represents a naphthyl group, R ₂ represents hydrogen, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a dialkylamino group, a diaralkylamino group or a diarylamino group, and n is an integer of 1 to 4 When n is 2 or more, R _{2 s} may be the same or different. R ₃ represents hydrogen or a methoxy group. ] (4) (described in Japanese Patent Publication No. 51-10983)

[Chemical 4] [In the formula, R ₁ represents an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group or a heterocyclic group, and R ₂ ,
R ₃ may be the same or different and each represents hydrogen, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a chloroalkyl group, a substituted or unsubstituted aralkyl group,
R ₂ and R ₃ may be bonded to each other to form a nitrogen-containing heterocycle. R _{4 s} may be the same or different and each represents hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group or halogen. (5) (described in JP-A-51-94829)

[Chemical 5] [In the formula, R represents hydrogen or a halogen atom, and Ar represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group or carbazolyl group. (6) (described in JP-A-52-128373)

[Chemical 6] [In the formula, R ₁ is hydrogen, halogen, a cyano group, or a carbon number of 1 to 1.
4 represents an alkoxy group having 4 or an alkyl group having 1 to 4 carbon atoms, and Ar is

[Chemical 6- (1)] R ₂ represents an alkyl group having 1 to 4 carbon atoms,
R ₃ represents hydrogen, halogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a dialkylamino group, n is 1 or 2, and when n is 2, R ₃
May be the same or different, R ₄ and hydrogen, carbon number 1
~ 4 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted benzyl group. (7) (described in JP-A-56-29245)

[Chemical 7] [Wherein R is a carbazolyl group, a pyridine group, a thienyl group, an indolyl group, a furyl group or a substituted or unsubstituted phenyl group, a styryl group, a naphthyl group or an anthryl group, and these substituents are dialkylamino groups,
Alkyl group, alkoxy group, carboxy group or ester thereof, halogen atom, cyano group, aralkylamino group,
It represents a group selected from the group consisting of an N-alkyl-N-aralkylamino group, an amino group, a nitro group and an acetylamino group. (8) (described in JP-A-58-58552)

[Chemical 8] [In the formula, R ₁ represents a lower alkyl group or a benzyl group, R ₂ represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, an amino group, or an amino group substituted with a lower alkyl group or a benzyl group. Represents a group, and n represents an integer of 1 or 2. (9) (described in JP-A-57-73075)

[Chemical 9] [Wherein R ₁ represents a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, R ₂ and R ₃ represent an alkyl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aryl group, and R ₄ represents It represents a hydrogen atom or a substituted or unsubstituted phenyl group, and Ar represents a substituted or unsubstituted phenyl group or naphthyl group. (10) (described in JP-A-58-198043)

[Chemical 10] [In the formula, n is an integer of 0 or 1, R ₁ is a hydrogen atom, an alkyl group or a substituted or unsubstituted phenyl group,
Ar ₁ represents a substituted or unsubstituted aryl group, R ₅
Represents an alkyl group including a substituted alkyl group, or a substituted or unsubstituted aryl group, and A represents

[Chemical 10- (1)]9-anthryl group or substituted or unsubstituted N-ar
Represents a carbcarbazolyl group, where R_FourIs a hydrogen atom,
Alkyl group, alkoxy group, halogen atom or  A group, a substituted or unsubstituted aryl group, R_Fiveand
R₆May form a ring), and m is 0, 1, 2
Or an integer of 3 and when m is 2 or more, R₂Is the same
It may be one or different. (11) (described in JP-A-49-105537)

[Chemical 11] [In the formula, R ₁ , R ₂ and R ₃ R ₃ represent hydrogen, a lower alkyl group, a lower alkoxy group, a dialkylamino group or a halogen atom, and n represents 0 or 1. (12) (described in JP-A-52-139066)

[Chemical 12] [Wherein R ₁ and R ₂ represent an alkyl group containing a substituted alkyl group or a substituted or unsubstituted aryl group, and A 1
Represents a substituted amino group, or a substituted or unsubstituted aryl group or allyl group. ]

[Chemical 13] [Wherein, X represents a hydrogen atom, a lower alkyl group, or a halogen atom, and R represents an alkyl group containing a substituted alkyl group,
Alternatively, it represents a substituted or unsubstituted aryl group, and A represents a substituted amino group or a substituted or unsubstituted aryl group. ] The compound represented by Chemical formula 1 is, for example, 9-ethylcarbazole-3-aldehyde-1-methyl-1-
Phenylhydrazone, 9-ethylcarbazole-3-aldehyde-1-benzyl-1-phenylhydrazone, 9
-Ethylcarbazole-3-aldehyde-1,1-diphenylhydrazone and the like. Examples of the compound represented by Chemical formula 2 include 4-diethylaminostyryl-β-aldehyde-1-methyl-1-phenylhydrazone, 4-methoxynaphthalene-1-aldehyde-1-benzil-1.
-Such as phenylhydrazone. The compound represented by Chemical formula 3 includes 4-methoxybenzaldehyde-1
-Methyl-1-phenylhydrazone, 2,4-dimethoxybenzaldehyde-1-benzyl-1-phenylhydrazone, 4-diethylaminobenzaldehyde-1,1
-Diphenylhydrazone, 4-methoxybenzaldehyde-1-benzyl-1- (4-methoxy) phenylhydrazone, 4-diphenylaminobenzaldehyde-1-
Examples thereof include benzyl-1-phenylhydrazone and 4-dibenzylaminobenzaldehyde-1,1-diphenylhydrazone. Examples of the compound represented by Chemical formula 4 include:
1,1-bis (4-dibenzylaminophenyl) propane, tris (4-diethylaminophenyl) methane,
1,1-bis (4-dibenzylaminophenyl) propane, 2,2'-dimethyl-4,4'-bis (diethylamino) -triphenylmethane and the like. Examples of the compound represented by Chemical formula 5 include 9- (4-diethylaminostyryl) anthracene and 9-bromo-10- (4-diethylaminostyryl) anthracene. Examples of the compound represented by Chemical formula 6 include 9- (4-dimethylaminobenzylidene) fluorene and 3- (9-fluorenylidene) -9-ethylcarbazole. The compound represented by Chemical formula 7 is, for example, 1,2-bis (4-diethylaminostyryl) benzene. Examples of the compound represented by Chemical formula 8 include 3-styryl-9-ethylcarbazole and 3- (4-methoxystyryl) -9-ethylcarbazole. Examples of the compound represented by Chemical formula 9 include 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 4-ditolylaminostilbene, 1- (4-diphenylaminostyryl) naphthalene, 1- (4-diethylaminostyryl). There is naphthalene. The compound represented by Chemical formula 10 is, for example,
4'-diphenylamino-α-phenylstilbene,
4'-N, N-bis (4-methylphenyl) amino-α
-Phenylstilbene and the like. Examples of the compound represented by Chemical formula 11 include 1-phenyl-3- (4-diethylaminostyryl) -5- (4-diethylaminophenyl) pyrazoline and 1-phenyl-3- (4-dimethylaminostyryl) -5-. (4-dimethylaminophenyl)
There is pyrazoline. Examples of the compound represented by Chemical formula 12 include 2,5-bis (4-diethylaminophenyl) -1,3,4-oxadiazole, 2-N, N-diphenylamino-5- (4-diethylaminophenyl)
-1,3,4-oxadiazole, 2- (4-dimethylaminophenyl) -5 (4-dimethylaminophenyl)
1.3,4-oxadiazole and the like. Examples of the compound represented by Chemical formula 13 include 2-N, N-diphenylamino-5- (N-ethylcarbazol-3-yl)-
1,3,4-oxadiazole, 2- (4-diethylaminophenyl) -5- (N-ethylcarbazole-3-
Yl) -1,3,4-oxadiazole and the like. Still other examples of the electron donating compound are listed below. (14) (described in Japanese Patent Publication No. 58-32372)

[Chemical 14] [In the formula, R ₁ represents a lower alkyl group, a lower alkoxy group, or a halogen atom, and n represents an integer of 0 to 4,
R ₂ and R ₃ may be the same or different and each represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, or a halogen atom. ] (15) (described in Japanese Patent Application No. 1-280763)

[Chemical 15] [Wherein R ₁ , R ₃ and R ₄ are a hydrogen atom, an amino group, an alkoxy group, a thioalkoxy group, an aryloxy group, a methylenedioxy group, a substituted or unsubstituted alkyl group,
A halogen atom or a substituted or unsubstituted aryl group, R ₂ represents a hydrogen atom, an alkoxy group, a substituted or unsubstituted alkyl group, or halogen. However, R
Except when ₁ , R ₂ , R ₃ and R ₄ are all hydrogen atoms. In addition, k, l, m and n are integers of ₁ , ₂ , 3 or 4, and when each is an integer of 2, 3 or 4, R ₁ , R ₂ , R ₃ and R ₄ may be the same. May be different. ] (16) (described in Japanese Patent Application No. 1-77839)

[Chemical 16] [In the formula, Ar represents a condensed polycyclic hydrocarbon group having 18 or less carbon atoms, and R ₁ and R ₂ represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group,
It represents a substituted or unsubstituted phenyl group, which may be the same or different. ]

(17) (described in Japanese Patent Application No. 62-98394)

A-CH = CH-Ar-CH = CH-A [In the formula, Ar is a substituted or unsubstituted aromatic hydrocarbon group.
And A is Represents a hydrogen group, R₁And R₂Is a substituted or non-replaced
Alkyl group, or substituted or unsubstituted alkyl group, alkyl group
It is a reel group). ]

(18) (described in Japanese Patent Application No. 2-94812)

[Chemical 18] [In the formula, Ar represents an aromatic hydrocarbon group, a hydrogen atom, a substituted or unsubstituted alkyl group, or an aryl group. When n is 0 or 1 and m is 1 or 2, and when n = 0 and m = 1, Ar and R may jointly form a ring. ]

Examples of the benzidine compound represented by the formula 14 include N, N'-diphenyl-bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine and 3,3 '. -Dimethyl-N, N, N ', N'-tetrakis (4-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine and the like. Examples of the biphenylamine compound represented by Chemical formula 15 include 4'-methoxy-N, N-diphenyl- [1,1'-biphenyl] -4-amine, 4'-methyl-N, N-bis (4-
Methylphenyl)-[1,1′-biphenyl] -4-amine, 4′-methoxy-N, N-bis (4-methylphenyl)-[1,1′-biphenyl] -4-amine and the like. Examples of the trianolamine compound represented by Chemical formula 16 include 1-N, N-diphenylaminopyrene and 1
-N, N-bis (p-tolylamino) pyrene and the like. Examples of the diolefin aromatic compound represented by Chemical formula 17 include 1,4-bis (4-N, N-diphenylamino) styrylbenzene and 1,4-bis [4-N, N-
Bis (p-tolyl) amino] styrylbenzene and the like. Examples of the stilpyrene compound represented by Chemical formula 18 include 1- (4-N, N-diphenylamino) styrylpyrene and 1- [4-N, N-bis (p-tolyl) amino].
There is still pyrene.

In particular, a substance that transports a negative charge, that is, an electron may be used for the electrophotographic photoreceptor. Examples of the electron transport material include chloranil, bromanil, tetracinoethylene, tetracyanoquinodimethane, 2,4,7-
Trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro- Indeno 4H-indeno [1,2-b] thiophen-4-one, 1,3,7-
Examples include trinitrodibenzothiophene-5,5-dioxide.

As the resin binder of the charge transfer layer for compatibilizing or dispersing the above charge transfer substances, polycarbonate, polyarylate, polyacrylate, polyester, polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer are used. , Styrene-maleic anhydride copolymer, polyvinyl chloride, polyvinyl acetate,
Vinyl chloride-vinyl acetate copolymer, polyvinylidene chloride, phenoxy resin, cellulose acetate, ethyl cellulose, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, silicone resin, epoxy resin, melamine resin, urethane resin, Examples include thermoplastic or thermosetting resins such as phenolic resins and alkyd resins. These may be used alone or in combination.

As the solvent at this time, tetrahydrofuran, dioxane, cyclohexane, toluene, monochlorobenzene, dichloroethane, methylene chloride or the like can be used. The solvent may also be used alone or in combination of two or more.

If desired, a plasticizer and a leveling agent may be added. Examples of the plasticizer include halogenated paraffin, dimethyl naphthalene, dibutyl phthalate,
Examples thereof include polymers and copolymers of dioctyl phthalate, tricresyl phosphate and the like, polyester and the like. Examples of the leveling agent include silicone oil and perfluoro group-containing oligomer or polymer.

Further, in the present invention, an intermediate layer of polyamide, polyvinyl alcohol, polyvinyl acetal, polyacrylic acid, polyhydroxymethacrylate, epoxy resin or the like is provided between the support and the photosensitive layer, or the resin and a white pigment such as an oxide. It is also possible to provide a white pigment layer made of titanium, zinc oxide, magnesium oxide, barium sulfate, and lithopone. The thickness of the intermediate layer or the white pigment layer is suitably 0.05 to 10 μm, preferably 0.2.
The film thickness is about 5 μm.

[0041]

【Example】

Hereinafter, the present invention will be described in more detail with reference to Examples. Example 1 Polyamide (CM8000, manufactured by Toray Industries, Inc.) was formed as an undercoating layer of about 0.2 μm on an 80 mmφ aluminum cylinder, and a cyclohexanone dispersion liquid of the following azo pigment was applied by dip coating and heating and drying to the above. A charge generation layer of 0.1 μm was formed.

[Chemical 19] Next, a charge transfer material (D) represented by the following structural formula 20 and a binder resin (R) represented by the following structural formula 21 and having a viscosity average molecular weight of 50,000 were used as D / R = 5/10 (weight ratio). ,
A coating solution for charge transfer layer (prepared to have a solid content concentration of 15% (solvent: methylene chloride solution) and then added with 0.1% (ratio to R) of silicone oil (KF-50, manufactured by Shin-Etsu Silicone Co., Ltd.) A solvent: methylene chloride solution) was applied on the charge generation layer by dip coating and dried by heating to form a charge transfer layer of about 22 μm to prepare an electrophotographic photoreceptor.

[Chemical 20]

[Chemical 21]

Next, the above electrophotographic photosensitive member was mounted on a copying machine of the following specifications by the usual Carlson process, and a copying test was performed on 100,000 sheets. Image evaluation and the eddy current type film thickness before and after the copying test were used. It was measured with a meter. (Copier specifications) Cleaning blade Material: Polyurethane resin Rebound: 50% Hardness: 70 ° Contact angle: 20 ° Cleaning brush Material: Acrylic resin Copy speed: 40 sheets / minute After installing the electrophotographic photoreceptor before the copy test on a modified machine that removes the charging device, developing device, transfer device, cleaning brush, and installed a torque meter, provide a thin layer of developer on the electrophotographic photosensitive member, and expose and pass the paper. The surface friction coefficient was determined from the torque detected by rotating the electrophotographic photosensitive member without contacting only the cleaning blade.

Example 2 Example 1 except that the amount of silicone oil added was changed to 2%.
Samples were prepared and evaluated in the same manner as in.

Example 3 A sample was prepared and evaluated in the same manner as in Example 1 except that the amount of silicone oil added was changed to 0.05%.

Example 4 Example 1 except that the amount of silicone oil added was changed to 5%.
Samples were prepared and evaluated in the same manner as in.

Example 5 Samples were prepared and evaluated in the same manner as in Example 1 except that 0.1% (R ratio) of a fluorine-containing surfactant (Diffense MCF300, manufactured by Dainippon Ink and Chemicals, Inc.) was added.

Example 6 Samples were prepared and evaluated in the same manner as in Example 5 except that the amount of the fluorine-containing surfactant added was changed to 1%.

Example 7 A sample was prepared and evaluated in the same manner as in Example 5 except that the amount of the fluorine-containing surfactant added was changed to 0.05%.

Example 8 A sample was prepared and evaluated in the same manner as in Example 1 except that the amount of the fluorine-containing surfactant added was changed to 2%.

Example 9 Samples were prepared and evaluated in the same manner as in Example 5 except that the fluorine-containing surfactant was changed to Defensa MCF300 (manufactured by Dainippon Ink and Chemicals, Inc.).

Example 10 A sample was prepared and evaluated in the same manner as in Example 5, except that the fluorine-containing surfactant was changed to MODIPER FT1329 (manufactured by NOF CORPORATION).

Comparative Example 1 A sample was prepared and evaluated in the same manner as in Example 1 except that the amount of silicone oil added was changed to 0.01%.

Comparative Example 2 A sample was prepared in the same manner as in Example 1 except that the amount of silicone oil added was changed to 10%, but the sample could not be prepared because the coating liquid became cloudy.

Comparative Example 3 Fluorosurfactant was added to 0.1 without addition of silicone oil.
%, Samples were prepared and evaluated in the same manner as in Example 1 except that the addition was made.

Comparative Example 4 A sample was prepared in the same manner as in Example 1 except that the amount of the fluorine-containing surfactant added was changed to 5%. However, the sample could not be prepared because the coating liquid became cloudy.

The results are shown in Table 16.

[Table 16] In Comparative Example 1 and Comparative Example 3, the cleaning test could not be performed because the cleaning blade was cracked and cleaning failure occurred.

Example 11 An 80 mmφ aluminum cylinder was dip-coated with the following coating solution for an intermediate layer and dried by heating to form an intermediate layer of about 30 μm. (Intermediate layer coating solution) alkyd resin (BECKOLITE M-6401, manufactured by Dainippon Ink and Chemicals, Inc.) 3 parts by weight Melamine resin (SUPER BECKAMINE G-821, manufactured by Dainippon Ink and Chemicals, Inc.) 2 parts by weight TiO ₂ (CR- (EL, manufactured by Ishihara Sangyo Co., Ltd.) 30 parts by weight Methyl ethyl ketone 15 parts by weight Disperse a liquid for 24 hours, then add methyl ethyl ketone /
Diluted with isopropyl alcohol = 11/9 parts by weight to obtain a coating liquid for intermediate layer. Next, a cyclohexanone dispersion of the following azo pigment was applied by dip coating and heat drying to form a charge generation layer of about 0.1 μm.

[Chemical formula 22]

Next, a charge transfer material (D) represented by the following structural formula 23 and a binder resin (R) having a viscosity average molecular weight of 50,000 represented by the following structural formula 24 and D / R = 5/10.
(Weight ratio) and solid content concentration of 15% (solvent: methylene chloride solution) and then adjusted to silicon oil (KF-5).
0, manufactured by Shin-Etsu Silicone Co., Ltd., 1.0% (ratio to R), and a fluorine-based surfactant (Modiper FT1329, manufactured by NOF CORPORATION) 0.1% (compared to R) for charge transfer layer coating. A liquid (solvent: methylene chloride solution) was applied onto the charge generation layer by dip coating and heat-dried to form a charge transfer layer of about 30 μm to prepare an electrophotographic photoreceptor.

[Chemical formula 23]

[Chemical formula 24]

Next, the above electrophotographic photosensitive member was mounted on a copying machine of the following specifications by a usual Carlson process, and a copying test was performed on 100,000 sheets to evaluate the image thickness and the thickness of the photosensitive layer before and after the copying test as an eddy current type film thickness. It was measured with a meter. (Copier specifications) Cleaning blade Material: Polyurethane resin Rebound: 55% Hardness: 65 ° Contact angle: 15 ° Contact pressure: 17g / cm Cleaning brush Material: Polyester resin Copy speed: 60 sheets / minute

Example 12 A sample was prepared in the same manner as in Example 11 except that the fluorine-containing surfactant was changed to Defencer MCF312 (manufactured by Dainippon Ink and Chemicals), and the same evaluation was performed.

Example 13 A sample was prepared and evaluated in the same manner as in Example 11 except that the contact angle of the cleaning blade was changed to 10 °.

Example 14 A sample was prepared and evaluated in the same manner as in Example 11 except that the contact angle of the cleaning blade was changed to 30 °.

Comparative Example 5 A sample was prepared and evaluated in the same manner as in Example 11 except that the contact angle of the cleaning blade was changed to 3 °.

Comparative Example 6 A sample was prepared and evaluated in the same manner as in Example 11 except that the contact angle of the cleaning blade was changed to 60 °.

Comparative Example 7 A sample was prepared and evaluated in the same manner as in Example 11 except that the contact angle of the cleaning blade was changed to 110 °. Table 17 shows the copy test results.

[0066]

[Table 17]

EFFECT OF THE INVENTION Since the electrophotographic photosensitive member of the present invention has a surface friction coefficient (μ) of 1.5 [−] or less, it has high sensitivity and excellent abrasion resistance, Even when used, there is no defect such as poor cleaning of the developer, and scratches and wear on the surface due to rubbing of the cleaning brush and cleaning blade are reduced.

Front page continuation (72) Inventor Hiroyuki Kishi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Tomohiro Inoue 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Yoshiaki Kawasaki 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd.

Claims (4)

[Claims] 1. An electrophotographic photosensitive member for use in an image forming apparatus having a cleaning means in which a cleaning blade is brought into contact with the rotating direction of the electrophotographic photosensitive member in a counter direction, the surface friction coefficient of the electrophotographic photosensitive member. (Μ)
Is 1.5 [-] or less. 2. The electrophotographic photosensitive member according to claim 1, wherein the outermost surface layer contains silicon oil in an amount of 0.05 to 5% (weight ratio) with respect to the binder resin. 3. The electrophotographic photosensitive member according to claim 1, wherein the outermost surface layer contains both silicone oil and a fluorine-containing surfactant. 4. Silicon oil is contained in an amount of 0.05 to 5% (weight ratio) with respect to the binder resin, and a fluorine-containing surfactant is included in an amount of 0.05 to 2% (weight ratio) with respect to the binder resin. The electrophotographic photosensitive member according to claim 3, wherein