JPH05158250A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a highly durable positively charged electrophotographic sensitive body enhanced in wear resistance, capable of obtaining a high-quality picture without causing blur, etc., having an excellent cleaning property and without deteriorating the picture due to the toner filming on the surface layer of the photosensitive body by incorporating a charge generating material, a charge-transfer material and polycarbonate resin and further a lubricant and a reinforcing agent into the charge generating layer. CONSTITUTION:A charge-transfer layer 2 and a charge generating layer 3 are laminated in this order on a conductive substrate 1 to constitute an electrophotographic sensitive body. In this case, the charge generating layer 3 contains a charge generating material, a charge-transfer material and polycarbonate resin and further contains a lubricant and a reinforcing agent. The polycarbonate resin is used as the binder resin for the photosensitive layer, various lubricants are dispersed in the binder resin of the charge generating layer 3, and the lubricant content is controlled to 10-50wt.% of the binder resin. The content of the selected reinforcing agent is adjusted to 10-200wt.% of the binder resin, and the reinforcing agent content is controlled to 1-1000wt.% of the lubricant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive charging electrophotographic photoreceptor having a charge transport layer and a charge generating layer in this order on a conductive support.

[0002]

2. Description of the Related Art Heretofore, in order to form an image by an electrophotographic method, a so-called Carlson method is generally used.
An electrostatic latent image is formed by uniformly charging and imagewise exposing the surface of the photoconductor, and the latent image is developed to form a toner image, which is transferred and fixed on a transfer material to form an image. Be seen.

On the other hand, the photosensitive member after transfer is subjected to static elimination by a static eliminator and rubbing a cleaning member such as a cleaning blade or a cleaning brush to remove residual toner, and is repeatedly used for a long period of time.

Therefore, as an electrophotographic photosensitive member, of course, electrophotographic characteristics such as good charging characteristics and sensitivity and small dark decay, as well as printing durability after repeated use, abrasion resistance,
It is also required to have good physical properties such as humidity resistance, and resistance (environmental resistance) to ozone generated during corona discharge and ultraviolet rays during exposure.

Conventionally, selenium has been used as an electrophotographic photoreceptor.
Inorganic photoreceptors having a photosensitive layer containing an inorganic photoconductive substance such as zinc oxide and cadmium sulfide as a main component are widely used. On the other hand, the use of various organic photoconductive materials as materials for the photosensitive layer of an electrophotographic photoreceptor has been actively developed and studied in recent years.

For example, Japanese Patent Publication No. 50-10496 discloses an organic photoreceptor having a photosensitive layer containing poly-N-vinylcarbazole and 2,4,7-trinitro-9-fluorenone. However, this photoreceptor is not always satisfactory in sensitivity and durability.

In order to improve such drawbacks, an organic photoconductor having high sensitivity and high durability is developed by separately sharing a charge generation function and a charge transport function in different materials in a photosensitive layer. Attempts are being made. In this kind of function-separated type electrophotographic photoreceptor,
Since a substance exhibiting each function can be selected from a wide range, it is possible to relatively easily manufacture an electrophotographic photoreceptor having arbitrary characteristics. According to such an organic electrophotographic photoreceptor, since the photosensitive layer can be formed by coating, the manufacturing cost is low, pollution and environmental pollution can be prevented, and various shapes (sheet shape, etc.) can be easily processed.

However, the organic electrophotographic photoreceptor has the following drawbacks, and there is a strong demand for solving these drawbacks.

(A) For example, since a layer is formed by binding a low molecular weight organic compound with a high molecular weight organic resin (binder), the mechanical strength is not always sufficient, and the photoreceptor is used in a non-wearing state. At times, the surface of the photoreceptor is scratched or worn due to rubbing of the developing blade.

(B) The photoconductor is mainly used for negative charging. As described in JP-A-60-247647, a thin charge generating layer is provided on a support and a relatively thick charge is formed on the support. It is configured to have a transport layer.

The reason for this is that when negatively charged, a hole transporting material can be used, which is advantageous in terms of high sensitivity and the like, while an electron transporting material has excellent characteristics. This is because it is extremely rare, has toxicity or carcinogenicity, and cannot be used.

In addition, when the photoconductor is negatively charged by using the hole transporting material, a large amount of ozone is generated at the time of charging to deteriorate the environmental conditions. Further, the ozone and other ionic substances are adsorbed on the surface of the photoconductor to deteriorate the material, and repeated use causes a decrease in potential, an increase in residual potential, a decrease in sensitivity, a decrease in image quality, and a decrease in life of the photoconductor. ..

Therefore, research and development have been carried out on a positive charging photoreceptor having a charge transport layer containing a charge transport substance having a hole transport property on a support and a charge generation layer as a surface layer on the charge transport layer. .. According to the photoconductor for positive charging, generation of ozone during charging is extremely small, which is advantageous in environmental hygiene.

However, the charge generating layer provided as the surface layer contains the charge generating substance in the form of fine particles at a high density,
There is a problem that it is easily worn and deteriorated due to mechanical shock, changes in temperature and humidity conditions, and the like.

Therefore, for example, JP-A-2-189550, JP-A-2-189551, JP-A-2-236555, and JP-A-2-23
6556, and JP-A-2-240655, etc., as a binder resin of the surface layer of the photoreceptor, various substituted polycarbonate, cyclic polycarbonate containing a central carbon atom, polycarbonate having a silicon atom as a central atom, polycarbonate-polycarbonate Various polycarbonates such as siloxane block copolymers have been proposed.

It has been pointed out that these polycarbonates are excellent in dispersibility of a charge generating substance and film characteristics, are resistant to photoelectric fatigue deterioration due to repeated charging exposure, and are excellent in mechanical abrasion resistance.

By the way, in recent copying machines and the like, high speed, high durability, and high image quality are demanded, and therefore, further improvement in film strength of the surface layer of the photoreceptor has been demanded. By the way, as one of the measures against the film strength of the surface layer of the photoconductor, for example, in JP-A-61-117558, SiO ₂ , CrO ₂ , Al ₂ O ₃ , SiC, TiO ₂ , as a reinforcing agent in the photoconductive layer, It has been proposed to incorporate inorganic compound particles such as ZnO.

Further, JP-A-63-30850 and JP-A-64-3
Japanese Patent No. 5448 describes a technique of incorporating a solid lubricant and silicone oil into the surface layer of a photoreceptor. Further, JP-A-2-189550 and JP-A-2-189551 propose techniques for incorporating a polycarbonate resin and a fluororesin or fluororesin particles into the surface layer of a photoreceptor.

However, in an organic photoreceptor for positive charging, which contains an organic photoconductive pigment in a high density and has a thin charge generating layer as a surface layer, high durability and high image quality which are required recently are achieved. Insufficient to do so, image defects such as image blur and image unevenness are unavoidable due to abrasion and damage of the photosensitive layer surface during repeated image formation, and further improvement of film properties is desired. It is rare.

[0020]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member for positive charging which is free from abrasion of the surface due to friction, scratches, image blurring and the like and which provides a high quality copied image. Another object of the present invention is to provide a highly durable electrophotographic photosensitive member which has good cleaning properties and does not cause image deterioration due to toner filming on the surface layer of the photosensitive member.

Still another object of the present invention is to provide a positive charging electrophotographic photosensitive member which does not cause fogging due to an increase in residual potential during repeated image formation, and which can stably obtain high density and clear image quality. To provide.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to an electrophotographic photosensitive member comprising a conductive support and a charge transport layer and a charge generation layer laminated in this order, wherein the charge generation layer is a charge generation substance, a charge transport substance and a polycarbonate resin. And an lubricant and a reinforcing agent are contained in the electrophotographic photosensitive member.

In a preferred embodiment of the present invention, the charge generation layer contains an antioxidant.

The electrophotographic photoreceptor of the present invention will be described in detail below.

The drawings are schematic sectional views for explaining the layer structure of the electrophotographic photosensitive member of the present invention. 1 and 2, 1 is a conductive support, 2 is a charge transport layer, 3 is a charge generation layer, and 4 is an intermediate layer provided between the conductive support 1 and the charge transport layer 2. The charge generation layer 3 of the present invention
Contains at least one of polycarbonate resins having structural units represented by the following general formula (1), general formula (2), general formula (3) and general formula (4) as a binder resin.

[0026]

[Chemical 2]

R _{1 to} R ₈ in the general formula (1) are each a hydrogen atom, a halogen atom, a lower alkyl group or an aryl group,
R ₉ and R ₁₀ represent a hydrogen atom, a lower alkyl group or an aryl group. However, at least one of R _{1 to} R ₈ is a halogen atom, a lower alkyl group or an aryl group, or at least one of R ₉ and R ₁₀ is a lower alkyl group or an aryl group having 3 or more carbon atoms.

Further, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R _{8 in the} general formulas (2), (3) and (4) are used.
Represents a hydrogen atom, a halogen atom or a lower alkyl group, and R ₉ , R ₁₀ , R ₁₁ and R ₁₂ represent a hydrogen atom, a lower alkyl group or an aryl group. Z is an atomic group necessary for forming a carbocycle or a heterocycle, A ₁ is -C (R ₁₃ ) (R ₁₄ )-, -Si (R ₁₅ ) (R ₁₆ )-, -S-,
-SO _2- , -CO-, -O- or-(CH ₂ ) n- [wherein n is an integer of 2 or more, R ₁₃ and R ₁₄ are bonded to each other to form a carbocycle or a heterocycle, R Each of ₁₅ and R ₁₆ is a substituted or unsubstituted alkyl group or aryl group, and 1 and m are l (l + m) = 0.1 to 0.9. Specific examples of the repeating unit of the polycarbonate represented by the general formula (1) include the following.

[0029]

[Chemical 3]

[0030]

[Chemical 4]

[0031]

[Chemical 5]

[0032]

[Chemical 6]

Next, specific examples of the repeating unit of the polycarbonate represented by the general formula (2) are as follows.

[0034]

[Chemical 7]

[0035]

[Chemical 8]

[0036]

[Chemical 9]

[0037]

[Chemical 10]

Next, specific examples of the compound of the repeating unit of the polycarbonate represented by the general formula (3) are as follows.

[0039]

[Chemical 11]

[0040]

[Chemical 12]

Next, specific examples of the repeating unit of the polycarbonate-siloxane copolymer represented by the general formula (4) are as follows.

[0042]

[Chemical 13]

Among the various polycarbonates described above, the coating liquid for the charge generating layer, which uses the polycarbonates belonging to the general formulas (1) and (2) as a binder, has excellent dispersion stability of the charge generating substance and forms the charge generating layer. At this time, it is advantageous in terms of charging performance, repeatability, printing durability and mechanical strength, and since crystallization of the binder does not occur, it has advantages such as toner filming and other image defects.

Further, the polycarbonates of the general formulas (3) and (4) have not only the excellent characteristics peculiar to polycarbonate but also the excellent abrasion resistance of the photosensitive layer.

The polycarbonates represented by the above general formulas (1) to (4) are used as the main binder resin of the photosensitive layer of the present invention. In addition, bisphenol A has a structure in which two methyl groups are symmetrically bonded to the central carbon atom. So-called A Type polycarbonate, polyester, styrene acrylic resin, polyvinyl butyral resin or the like may be contained.

In order to increase the mechanical strength of the charge generation layer, a lubricant and a particulate reinforcing agent are contained.

As the lubricant, at least one selected from fluorine atom-containing resin or powder thereof, polyolefin resin or powder thereof, fatty acid ester, fatty acid metal salt and waxes is preferably used. Examples of the fluorine atom-containing resin or its powder include tetrafluoroethylene resin, trifluoroethylene chloride resin, hexafluoroethylene propylene resin, vinyl fluoride resin, vinylidene fluoride resin, fluorodichloroethylene resin, and the like. And the powder of each of the above resins and the like.

Examples of the polyolefin resin or its powder include homopolymer resins such as polyethylene resin, polypropylene resin, polybutene resin and polyhexene resin, copolymer resin powder such as ethylene-propylene copolymer and ethylene-butene copolymer. And terpolymer resins such as ethylene-propylene-hexene copolymer.

The fatty acid ester is a monohydric or polyhydric alcohol ester of a fatty acid having 8 to 35 carbon atoms, which is a solid form derived from an alcohol having 1 to 20 carbon atoms or a powder thereof. Examples thereof include methyl stearate, ethylene glycol monostearate, glyceryl tri (1,2-oxyl stearate), and 1,2,4-butanetriol tristearate.

The fatty acid metal salt has 8 carbon atoms.
There are ~ 35 saturated or unsaturated fatty acid metal salts.

Examples of the metal constituting the fatty acid metal salt include lithium, sodium, potassium, rubidium, magnesium, calcium, zinc, strontium, cadmium, barium, mercury, aluminum, chromium, tin, titanium, zirconium, lead, manganese. , Iron, cobalt, nickel, etc., and other ammonium fatty acid salts may be included. Further, as the fatty acid constituting the fatty acid metal salt, for example, caprylic acid, pelargonic acid, caproic acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, behenic acid. , Lignoceric acid, cerotic acid and the like. Further, a mixture of these fatty acids, alcohol esters, amides and the like of these fatty acids are also included in the present invention.

Examples of the waxes include carbowax, which is a solid wax having a molecular weight of up to 6000, such as polyethylene glycol and methoxy polyethylene glycol, and also cholesterol; techlorane or perchlorpentacyclodecane; having a molecular weight of about 4000 or less. Polycaprolactone; low molecular weight fluorocarbon compounds such as waxy short chain telomers of tetrafluoroethylene and low molecular weight polluting polytetrafluoroethylene powder.

The above-mentioned various lubricants are preferably 0.01 to
It is dispersed and contained in the binder resin of the charge generation layer as powder with a diameter of 3 μm, and the content is 1 to 50 with respect to the binder resin.
Weight%

Each of the above-mentioned lubricants is dispersed and contained in the charge generation layer forming the surface layer of the photoreceptor together with the particulate reinforcing agent described below, and the active species generated by corona discharge, development, transfer,
Increases durability against mechanical friction due to cleaning and the like.

As the reinforcing agent, at least one selected from acrylic resin fine particles, silicone resin fine particles, melamine resin fine particles, benzoguanamine resin fine particles, metal oxide fine particles, inorganic compound whiskers and the like is used.

As the acrylic resin fine particles, for example, thermosetting acrylic resin fine particles such as melamine-modified acrylic resin and epoxy-modified acrylic resin which are hardened with styrene-acrylic resin, methyl methacrylate resin or isocyanate compound are used.

The silicone resin particles include, for example, silicone resins such as organopolysiloxane, and other thermosetting resins such as acrylic modified silicone resin, epoxy modified silicone resin, alkyd modified silicone resin, polyester modified silicone resin, urethane modified silicone resin. Fine particles are used.

As the melamine resin fine particles, fine particles of thermosetting resin obtained from melamine and formaldehyde are used.

Further, as the benzoguanamine resin fine particles, fine particles of a thermosetting resin obtained from benzoguanamine and formaldehyde are used.

Examples of the metal oxide fine particles include Si
_{O 2, CrO 2, Al 2} O 3, CeO 2, Fe 2 O 3, TiO 2, ZnO, ZrO 2, Mg0
And the like are used.

As the inorganic compound whiskers, for example, a mustache-shaped single crystal body of potassium titanate, calcium titanate, silicon carbide, silicon nitride or the like is used.

The reinforcing agent is usually in the form of fine particles having a diameter of 5 μm or less, preferably 0.05 to 3 μm, and is contained in an amount of 10 to 200% by weight with respect to the binder resin of the charge generation layer. The content ratio of the reinforcing agent to the lubricant contained in the layer is 1 to 1000% by volume.

In order to improve the dispersibility of the reinforcing agent in the charge generation layer, it is preferable to treat the particle surface with a surface active agent, a silane coupling agent, or the like.

In the present invention, as described above, an intermediate layer is formed on a conductive support if necessary, a charge transport layer is provided as a lower layer thereon, and a charge generation layer as a surface layer is further provided thereon to form a photosensitive layer. The charge-generating layer contains a charge-transporting substance together with the charge-generating substance, so that the charge generated by absorbing light in the charge-generating layer can be quickly transferred to the lower charge-transporting layer. To achieve high sensitivity.

As the charge generating substance contained in the charge generating layer, the following organic photoconductive materials which absorb visible light and generate free carriers can be used.

(1) Azo pigments such as monoazo pigments, polyazo pigments, metal complex salt azo pigments, pyrazolone azo pigments, stilbene azo pigments and thiazole azo pigments (2) perylene pigments such as perylene anhydride and perylene imide ( 3) Anthraquinone-based or polycyclic quinone-based pigments such as anthraquinone derivatives, anthanthrone derivatives, dibenzpyrenequinone derivatives, pyranthrone derivatives, violanthrone derivatives and isobiolanthrone derivatives (4) Indigooid pigments such as indigo derivatives and thioindigo derivatives (4) 5) Phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine (6) Carbonium pigments such as diphenylmethane pigment, triphenylmethane pigment, xanthene pigment and acridine pigment (7) Azine pigment, oxazine pigment And thiazine pigments and other quinoneimine pigments (8) Cyanine pigments and azomethine pigments and other methine pigments (9) Quinoline pigments (10) Nitro pigments (11) Nitroso pigments (12) Benzoquinone and naphthoquinone pigments (13) Naphthalimide pigments (14) Perinone pigments such as bisbenzimidazole derivatives.

Among them, the pigments preferably used in the present invention include polycyclic quinone pigments represented by the following general formula (5), (6) or (7).

[0068]

[Chemical 14]

[In the above formulas, X is a halogen atom,
It represents a nitro group, a cyano group, an acyl group or a carboxyl group, n is an integer of 0 to 4 and m is an integer of 0 to 6. Specific examples of the polycyclic quinone pigment are disclosed in JP-A-60
-172044, pages 24-26. In addition, other charge generating substances that can be used include the following general formula (8)
Bisazo compound of.

[0070]

[Chemical 15]

[However, in this general formula (8), X ₁ , X ₂
Represents a hydrogen atom or a halogen atom.

A ₂ :

[0073]

[Chemical 16]

(X is a hydroxy group, or -N (R ²⁰ ) (R ²¹ ).
Or -NHSO ₂ -R ²² , wherein R ²⁰ and R ²¹ are respectively
Hydrogen atom, substituted or unsubstituted alkyl group, R ²² is a substituted or unsubstituted alkyl group or substituted or unsubstituted aryl group> Y
Is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, a carboxyl group, a sulfo group, a substituted,
Unsubstituted carbamoyl group or substituted or unsubstituted sulfamoyl group provided that when m is 2 or more, the groups may be different from each other. ) Z is a group of atoms necessary for constituting a substituted or unsubstituted carbocyclic aromatic ring or a substituted or unsubstituted heterocyclic aromatic ring, and R ¹⁹ is a hydrogen atom, a substituted or unsubstituted amino group. , A substituted or unsubstituted carbamoyl group, a carboxyl group or an ester group thereof, A ₃ is a substituted or unsubstituted aryl group, n is an integer of 1 or 2, and m is an integer of 0 to 4. Specific examples of the bisazo compound represented by the general formula (8) are described, for example, in JP-A-1-200361, pp. 3-10.

As another charge generating substance, a bisazo compound represented by the following general formula (9) can be used.

[0076]

[Chemical 17]

(However, in this general formula, A ₄ is

[0078]

[Chemical 18]

Z is a group of atoms necessary for forming a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle, Y is a hydrogen atom, a hydroxyl group, a carboxyl group or an ester group thereof. , Sulfo group, substituted or unsubstituted carbamoyl group, or substituted or unsubstituted sulfamoyl group, R ²³ : hydrogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted amino group, substituted or unsubstituted carbamoyl group A carboxyl group or an ester group thereof, or a cyano group, Ar ³ : a substituted or unsubstituted aryl group, R ²⁴ : a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted Represents an aryl group, a substituted or unsubstituted alkoxy group or a halogen atom. ) Specific examples of the bisazo compound represented by the general formula (9) are described on pages 2 to 4 of JP-A 1-219841.

The charge generating substance as described above is dispersed and contained in the polycarbonate binder resin in the form of fine particles having a diameter of 0.1 to 1 μm to form a layer.

It is essential that the charge generation layer as the surface layer of the photoreceptor of the present invention contains a charge transport substance together with the above-mentioned charge generation substance, and the charge transport substance as the lower layer is the charge transport substance. At least one selected from the group of the following charge transport substances contained in the layer is contained.

Examples of the charge transport material include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives,
Bisimidazolidine derivative, styryl compound, hydrazine compound, pyrazoline derivative, oxazolone derivative, benzothiazole derivative, benzimidazole derivative, quinazoline derivative, benzofuran derivative, acridine derivative, phenazine derivative, aminostilbene derivative, poly
-N-vinylcarbazole, poly-1-vinylpyrene, poly-9
-Vinyl anthracene and the like.

Specific examples include styryl compounds represented by the following general formula (10) or (11).

[0084]

[Chemical 19]

In the above general formula, R ²⁵ and R ²⁶ represent the following two groups which are substituted or unsubstituted; an alkyl group and an aryl group, the substituent being an alkyl group, an alkoxy group, a substituted amino group,
Examples thereof include a hydroxyl group, a halogen atom and an aryl group.

Ar ⁴ and Ar ⁵ represent a substituted or unsubstituted aryl group, and examples of the substituent include an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom and an aryl group.

R ²⁷ and R ²⁸ represent a substituted or unsubstituted aryl group or a hydrogen atom, and as the substituent, an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom or an aryl group is used.

[0088]

[Chemical 20]

In the above general formula, R ²⁹ is a substituted or unsubstituted aryl group, R ³⁰ is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, an amino group, a substituted amino group, a hydroxyl group, R ³¹ Is a substituted or unsubstituted aryl group, substituted,
It represents an unsubstituted heterocyclic group.

Further, the following general formula (1
The hydrazone compound of 2), (13), (14) or (15) can also be used.

[0091]

[Chemical 21]

In the formula, R ³² and R ³³ each represent a hydrogen atom or a halogen atom, R ³⁴ and R ³⁵ each represent a substituted or unsubstituted aryl group, and Ar ⁶ represents a substituted or unsubstituted arylene group.

[0093]

[Chemical formula 22]

In the formula, R ³⁶ is a methyl group, ethyl group, 2-hydroxyethyl group or 2-chloroethyl group, R ³⁷ is a methyl group, ethyl group, benzyl group or phenyl group, R ³⁸ is a methyl group, ethyl group, A benzyl group or a phenyl group is shown.

[0095]

[Chemical formula 23]

In the formula, R ³⁹ is a substituted or unsubstituted naphthyl group,
R ⁴⁰ represents a substituted or unsubstituted three groups; an alkyl group, an aralkyl group or an aryl group, R ⁴¹ represents a hydrogen atom, an alkyl group or an alkoxy group, and R ⁴² and R ⁴³ represent a substituted or unsubstituted three groups. Group: The same or different groups selected from an alkyl group, an aralkyl group and an aryl group are shown.

[0097]

[Chemical formula 24]

In the formula, R ⁴⁴ is a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, R ⁴⁵ is a hydrogen atom or a substituted,
The following two unsubstituted groups; an alkyl group, an aryl group, Q is a hydrogen atom, a halogen atom, an alkyl group, a substituted amino group,
It represents an alkoxy group or a cyano group, and m represents an integer of 0 or 1.

Further, as a charge transport material, the following general formula (1
The pyrazoline compound of 6) can also be used.

[0100]

[Chemical 25]

In the formula, n represents 0 or 1, R ⁴⁶ , R ⁴⁷ and R ⁴⁸ are a substituted or unsubstituted aryl group, R ⁴⁹ and R ⁵⁰ are a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, Alternatively, it represents a substituted or unsubstituted aryl group or aralkyl group. However,
Neither R ⁴⁹ nor R ⁵⁰ is a hydrogen atom, and n is 0.
Then R ⁴⁹ is not a hydrogen atom.

Further, the amine derivative represented by the following general formula (17) can also be used as the charge transport material.

General formula (17) Ar ⁹ -N (Ar ⁷ ) (Ar ⁸ ) In the formula, Ar ⁷ and Ar ⁸ represent a substituted or unsubstituted phenyl group,
As a substituent, a halogen atom, an alkyl group, a nitro group,
Alkoxy groups are used.

Ar ⁹ represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group, fluorenyl group or heterocyclic group, and the substituent is an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, an aryloxy group or an aryl group. , Amino group, nitro group, piperidino group, morpholino group, naphthyl group, anthryl group and substituted amino group. However,
An acyl group, an alkyl group, an aryl group, or an aralkyl group is used as a substituent of the substituted amino group.

Specific examples of the charge transport material represented by the general formulas (10) to (17) are described in JP-A-60-172044.

As the binder resin contained in the charge transport layer, all resins for electrophotography are useful,
For example, polyethylene, polypropylene, acrylic resin,
Methacrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl butyral resin, vinyl formal resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, silicone resin, melamine resin, etc. Addition type resins, polycondensation type resins, and copolymer resins containing two or more of repeating units of these resins, for example, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate
In addition to insulating resins such as maleic anhydride copolymer resin, polymer organic semiconductors such as poly-N-vinylcarbazole can be mentioned. The polycarbonate resins of the general formulas (1) to (4) for the charge generation layer are preferably used as the polycarbonate resin.

Hereinafter, the layer structure of the photoreceptor of the present invention will be described more specifically with reference to FIG.

In the figure, the conductive support 1 may be formed of either a conductive material or an insulating material. Examples of the conductive material include metals such as stainless steel, aluminum, chromium, molybdenum, iridium, tellurium, titanium, platinum and palladium, and alloys thereof. Examples of the insulating material include a film or sheet of synthetic resin such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene and polyamide, glass, ceramic, paper and the like. When an insulating material is used, its surface is preferably subjected to a conductive treatment. In particular,
For example, in the case of glass, conductive treatment is performed with indium oxide, tin oxide, etc., and in the case of synthetic resin film such as polyester film, aluminum, silver, lead, nickel,
Conductive treatment of metal such as gold, chromium, molybdenum, iridium, niobium, tantalum, vanadium, titanium, platinum by vacuum vapor deposition, electron beam vapor deposition, sputtering or the like or by laminating with the above metal. ..

An intermediate layer 4 is preferably provided on the conductive support 1 for the purpose of preventing charge injection from the support 1 and improving the adhesiveness between the support 1 and the charge transport layer 2. Be done. In other words, in addition to the binder resin used in the charge transport layer, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, casein, starch and other organic polymer compounds are applied by dip coating, spray coating, or by vacuum deposition or sputtering of aluminum oxide or the like. The intermediate layer 4 having a thickness of 0.01 to 2 μm is formed by the above method. Then, 20 to 200 parts by weight, preferably 30 to 100 parts by weight of the charge transporting material is mixed with 100 parts by weight of the binder resin on the intermediate layer 4, and the charge transporting layer 2 having a thickness of 5 to 50 μm is contained.
Is formed. Then, a binder resin is formed on the charge transport layer 2.
5 to 500 parts by weight, preferably 20 to 100 parts by weight, of the charge generating substance are dispersed and contained in 100 parts by weight, the charge transporting substance is contained in a compatible amount of 20 to 200 parts by weight, and the lubricant is used in an amount of 1: 1. To 30 parts by weight, preferably 2 to 20 parts by weight, contained in a compatible or dispersed state, and the reinforcing agent in an amount of 5 to 200 parts by weight, preferably
The photoconductor of the present invention is obtained by laminating a charge generating layer 3 containing 0.05 to 10 μm in a thickness of 10 to 100 and further containing 0.1 to 100 parts by weight, preferably 1 to 50 parts by weight of the following antioxidant, if necessary. To get

Examples of the antioxidant include the following (I) group
Examples of the compound of group (V) are mentioned.

Group (I): Hindered phenols Dibutylhydroxytoluene, 2,2'-methylenebis (6-
t-butyl-4-methylphenol), 4,4'-butylidene bis (6-t-butyl-3-methylphenol), 4,4'-thiobis (6-t-butyl-3-methylphenol), 2, 2'-butylidene bis (6-t-butyl-4-methylphenol), α-tocophenol, β-tocophenol, 2,2,4-trimethyl-6-
Hydroxy-7-t-butylchroman, pentaerythyltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2'-thiodiethylenebis [3-
(3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,6-hexanediolbis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], butylhydroxy Anisole, dibutylhydroxyanisole, etc. Group (II): para-phenylenediamines N-phenyl-N′-isopropyl-p-phenylenediamine,
N, N'-di-sec-butyl-p-phenylenediamine, N'-phenyl-N-sec-butyl-p-phenylenediamine, N, N'-diisopropyl-p-phenylenediamine, N, N'-dimethyl -N,
N'-di-t-butyl-p-phenylenediamine and the like.

Group (III): Hydroquinones 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl
-5-Chlorohydroquinone, 2-t-octyl-5-methylhydroquinone, 2- (2-octadecenyl) -5-methylhydroquinone, etc.

Group (IV): Organic Sulfur Compounds Dilauryl-3,3'-thiodipropionate, distearyl-3-3'-thiodipropionate, ditetradecyl-3,
3'-thiodipropionate etc.

Group (V): Organophosphorus compounds Triphenylphosphine, tri (nonylphenyl) phosphine, tri (dinonylphenyl) phosphine, tricresylphosphine, tri (2,4-dibutylphenoxy) phosphine and the like.

These compounds are known as antioxidants for rubbers, plastics, fats and oils, and commercially available products are easily available.

Among the antioxidants of the groups (I) to (V), the hindered phenols of the group (I), which are particularly excellent in the antioxidant effect, are preferably used in the present invention.
In the photoconductor of the present invention, when the amount of the charge generating substance in the charge generating layer is less than 5 parts by weight with respect to 100 parts by weight of the binder resin, the light absorption is insufficient and the sensitivity is lowered to more than 500 parts by weight. In this case, the film becomes brittle and the mechanical strength is reduced.

When the amount of the charge transport material is less than 20 parts by weight with respect to 100 parts by weight of the binder resin, charge injection and transport are deteriorated and the sensitivity is lowered, and when it exceeds 200 parts by weight, the film becomes brittle and mechanical strength is increased. Is reduced.

Next, when the amount of the lubricant is less than 1 part by weight per 100 parts by weight of the binder resin, the lubricating effect cannot be obtained, and cleaning failure occurs or mechanical strength is reduced.
If it exceeds the weight part, the film becomes brittle and the mechanical strength is lowered.

Next, if the amount of the reinforcing agent is less than 10 parts by weight per 100 parts by weight of the binder resin, the effect of improving the film strength cannot be obtained, and if it exceeds 200 parts by weight, the film becomes brittle and the mechanical strength decreases. ..

Hereinafter, the present invention will be described in detail with reference to Examples, but the embodiments of the present invention are not limited thereto.

[0121]

[Example] 15 aluminum drums having a length of 355.5 mm and an outer diameter of 80 mmφ were prepared, each of which was coated with a coating solution for a charge transport layer having the following formulation by a dip coating method, dried at 100 ° C. for 30 minutes, and dried to a thickness of 20 μm. Was formed on the charge transport layer.

Coating solution formulation for charge transport layer: 1,2-dichloroethane 1000 parts by weight Polycarbonate (Mitsubishi Gas Chemical Co., Ltd. Iupilon Z-200) 160 parts by weight Charge transport material (CTM1) 120 parts by weight Silicon oil (manufactured by Shin-Etsu Silicon Co., Ltd. KF-54) 0.1 parts by weight Next, on the 15 aluminum drums having the charge transport layer, the composition of the basic formulation of the following charge generation layer coating solution was changed as shown in Table 1 to prepare 15 types of coating solutions. Then, these were coated by a circular slide hopper coating method so as to have a thickness of 2 μm, and 15 test photoconductors of Test Nos. 1 to 15 were obtained.

Test Nos. 1 to 12 are for the present invention, and Test Nos. 13 to 15 are for comparison.

Basic formulation of coating liquid for charge generation layer: 1,2-dichloroethane 1000 parts by weight Binder resin (A) 50 parts by weight Charge generation material (CGM) 25 parts by weight Charge transport material (CTM) 35 parts by weight Lubricant ( B) X parts by weight Reinforcing agent (C) Y parts by weight Antioxidant (D) Z parts by weight

[0125]

[Table 1]

The structures of the charge generating substance (CGM), the charge transporting substance (CTM) and the binder resin (A) used in the coating liquid for the charge generating layer in Table 1 are shown below.

[0127]

[Chemical formula 26]

The CGM3 had an X-ray diffraction spectrum with respect to Cu-K rays of 9.5 ± of the black angle 2θ.
It is a titanyl phthalocyanine in crystalline form with peaks at 2 °, 24.1 ± 0.2 ° and 27.2 ± 0.2 °.

[0129]

[Chemical 27]

[0130]

[Chemical 28]

[0131]

[Chemical 29]

Next, the substance names of the lubricant (B) and the reinforcing agent (C) contained in the coating liquid for the charge generating layer are shown in Table 2 below.
Shown in.

[0133]

[Table 2]

Structural formula of the lubricant B1 in Table 2 above:

[0135]

[Chemical 30]

Next, the chemical structural formula, manufacturer and trade name of the antioxidant (D) contained in the coating liquid for charge generating layer are shown below.

Structure of Antioxidant D1: Sumilizer BH
T Sumitomo Chemical Co., Ltd.

[0138]

[Chemical 31]

Structure of Antioxidant D2: Irganox 56
5 Made by Ciba Geigy

[0140]

[Chemical 32]

Structure of Antioxidant D3: Irganox 10
10 Made by Ciba Geigy

[0142]

[Chemical 33]

Structure of Antioxidant D4: Sumilizer MB
Sumitomo Chemical Co., Ltd.

[0144]

[Chemical 34]

[Test Method] The photoconductor for test No. 1
~ 12 and comparative photoconductor Nos. 13-15 are made by Konica U-BIX
Installed on a 3035 modified machine (correctly modified charging characteristics), repeated 100 times for each test in an atmosphere of relative humidity 60% and temperature 20 ° C.
Performed 00 times of live-action tests, and evaluated the degree of image density and fog at the 10000th time on three levels of "○", "△", and "×".
The results are shown in Table 3.

Further, the black paper potential (V _B ) and the white paper potential (V _W ) of the photoconductor at the initial and 10,000 times of the above-mentioned 10000 times repeated actual copying test were measured, and the results are shown in Table 3.

The black paper potential (V _B ) in Table 3 is the reflection density.
The surface potential of the photoconductor for the document of 1.3 and the white paper potential (V _W ) are the surface potential of the photoconductor for the document of reflection density "0", and the probe of the electrometer is placed at the position of the developing device before and after the actual copying. And measured.

Since a halogen lamp of 300 ° K is used as the exposure light source, considering the color balance,
An IR cut filter with a cut wavelength of 630 nm was placed in the optical path for testing. In the evaluation of the image quality of the live-action test, paying attention to the image density and the degree of fogging, the image density of 1.1 or more is "○", 0.9 to 1.1 is "△", and less than 0.9 is "x".
Fogging 0.50 or more is "x", 0.02 to 0.49 is "△", 0.02
Less than was designated as "○".

Further, the amount of wear on the surface of the photoreceptor was measured after 10,000 copies. That is, the film thickness of the photoconductor was measured at the initial stage and after copying 10,000 times, and the difference was taken as the amount of wear (μm) of the photoconductor, and the results are shown in Table 3.

The developer of this embodiment is U-BIX.
A developer for 5070 was used.

[0151]

[Table 3]

From Table 3, in the test according to the present invention, it is possible to achieve a high image quality for a long period of time because the amount of wear of the photoconductor is small during the repeated image formation, the electrostatic characteristic of the photoconductor is not deteriorated. However, in the comparative test, the abrasion amount of the surface layer of the photoconductor is large, an image defect occurs, or the electrophotographic performance is deteriorated. Therefore, the concentration decreases,
It is understood that the fog increases and the image quality deteriorates.

[0153]

EFFECT OF THE INVENTION Since the photoreceptor of the present invention is a positive charging photoreceptor having a charge transport layer as a lower layer and a charge generating layer and an upper layer, it is possible to prevent pollution such as ozone generation and also to the charge generating layer. By containing a specific binder resin, a lubricant, a reinforcing agent and, if necessary, an antioxidant, it is possible to give the photoreceptor a property of being highly resistant to photoelectric deterioration and mechanical abrasion and having high durability. When the photoconductor is used for a long period of time, high image quality can be stably obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a layer structure of a photoreceptor of the present invention.

FIG. 2 is a cross-sectional view showing a layer structure of a photoconductor of the present invention.

[Explanation of symbols]

 1 Conductive Support 2 Charge Transport Layer 3 Charge Generation Layer 4 Intermediate Layer

[Procedure amendment]

[Submission date] February 25, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0145

[Correction method] Change

[Correction content]

[Test Method] The photoconductor for test No. 1
~ 12 and comparative photoconductor Nos. 13-15 are made by Konica U-BIX 3
Mounted on 035 modified machine (correctly modified charging characteristics) and repeated 1000 times for each test under the atmosphere of relative humidity 60% and temperature 20 ° C.
Carried out 0 times of the live-action test, it showed the result in Table 3.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0148

[Correction method] Change

[Correction content]

Since a halogen lamp of 300 ° K is used as the exposure light source, considering the color balance,
An IR cut filter with a cut wavelength of 630 nm was placed in the optical path for testing .

Claims (6)

[Claims] 1. An electrophotographic photosensitive member comprising a conductive support and a charge transport layer and a charge generation layer laminated in this order, wherein the charge generation layer contains a charge generation substance, a charge transport substance and a polycarbonate resin. And an electrophotographic photoreceptor containing a lubricant and a reinforcing agent. 2. The lubricant contains at least one selected from a fluorine atom-containing resin or powder thereof, a polyolefin resin or powder thereof, a fatty acid ester, a fatty acid metal salt, and waxes. 1. The electrophotographic photosensitive member according to 1. 3. The reinforcing agent contains at least one selected from acrylic resin fine particles, silicon resin fine particles, melamine resin fine particles, benzoguanamine resin fine particles, metal oxide fine particles, and whiskers of inorganic compounds. Or the electrophotographic photosensitive member according to 2. 4. The polycarbonate resin comprises the following general formula (1), general formula (2), general formula (3) and general formula (4).
The electrophotographic photosensitive member according to claim 1, which contains at least one selected from the group consisting of a polymer or a copolymer having the structural unit shown by as a main repeating unit. [Chemical 1] [R _{1 to} R _{8 in} the general formula (1) are each a hydrogen atom, a halogen atom, a lower alkyl group or an aryl group, and are R ₉ , R _10;
Represents a hydrogen atom, a lower alkyl group, or an aryl group. However, at least one of R _{1 to} R ₈ is a halogen atom, a lower alkyl group or an aryl group, or at least one of R ₉ and R ₁₀ is a lower alkyl group or an aryl group having 3 or more carbon atoms. Further, in the general formula (2), the general formula (3) and the general formula (4), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each a hydrogen atom. A halogen atom or a lower alkyl group,
R ₉ , R ₁₀ , R ₁₁ and R ₁₂ represent a hydrogen atom, a lower alkyl group or an aryl group. Z is an atomic group necessary for forming a carbocycle or a heterocycle, A ₁ is -C (R ₁₃ ) (R ₁₄ )-, -Si (R ₁₅ ) (R ₁₆ )-, -S
_{-, - SO 2 -, -} CO -, - O- or - (CH ₂₎ n- (where, n is an integer of 2 or more, R ₁₃ and R ₁₄ combine to form a carbocyclic or heterocyclic ring; , R ₁₅ and R ₁₆ are each a substituted or unsubstituted alkyl group or aryl group, l and m
Represents l (l + m) = 0.1 to 0.9. ) 5. The electrophotographic photosensitive member according to claim 1, wherein the charge generation layer contains an antioxidant. 6. The electrophotographic photoreceptor according to claim 1, wherein the antioxidant comprises a hindered phenol compound.