JPH02254465A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To restrain deterioration of electrostatic chargeability of a photosensitive body due to repeated uses and to enhance stability and sharpness of a copied image for a long period by incorporating a specified trisazo pigment and a specified compound in a photosensitive layer. CONSTITUTION:The photosensitive layer of this photosensitive body contains the trisazo pigment of formula I in which A is a group of formula II or III or the like; X is a desired aromatic or heterocyclic ring; Ar1 is same as X; Ar2 is a desired aromatic ring; R1 is H, lower alkyl, or the like; and R2 is lower alkyl, carboxy, or the like, and the compound of formula V in which each of R4 - R7 is H, OH, or the like; and each of R8 and R9 H, alkenyl, or the like. The compound of formula I is used as an electric charge generating material, and its component is embodied by formula IV, and the component of formula V is embodied by alpha-tocopherol (5,7,8-trimethyltocol) of formula VI and the like.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrophotographic photoreceptor, and particularly to an electrophotographic photoreceptor that has excellent charging stability even when used repeatedly over a long period of time. .

[Conventional technology]

Inorganic materials such as selenium, cadmium sulfide, and zinc oxide have been conventionally known as photoconductive materials for electrophotographic photoreceptors. However, these inorganic materials do not necessarily satisfy the characteristics such as photosensitivity, thermal stability, and durability required for electrophotographic photoreceptors, as well as manufacturing conditions. For example, selenium tends to crystallize due to heat, dirt, etc., and its properties tend to deteriorate. In addition, it has drawbacks such as 1!2 manufacturing cost, impact resistance, toxicity, and other issues that require careful handling.

Photoreceptors using cadmium sulfide have poor moisture resistance and durability, and also have problems such as toxicity. Zinc oxide also has the disadvantage of poor moisture resistance and durability.

For electrophotographic photoreceptors using these inorganic photoconductive materials,
Photoreceptors using organic photoconductive substances are being actively researched and developed because of their light weight, ease of film formation, manufacturing cost, and wide variation as organic compounds. For example, in the early days, photoreceptors containing polyvinylcarbazole and 2,4,7-trinitro-9-fluorenone described in Japanese Patent Publication No. 50-10496;
A photoreceptor in which polyvinylcarbazole is sensitized with a pyrylium salt dye or a photoreceptor having a eutectic complex as a main component has been proposed, as described in Japanese Patent No. 8-25658. However, these photoreceptors do not have sufficient sensitivity and durability.

Therefore, in recent years, a functionally separated type photoreceptor in which a charge generation layer and a charge transport layer are separated has been proposed, and
A photoreceptor comprising a combination of chlordiane blue and a hydrazone compound as described in JP-A-53-133445, JP-A-5/1-21728, and JP-A-Sho 54- with a bisazo compound as the charge generating substance. 2283
4, as a charge transport material, JP-A-58-19
8043, JP-A-58-199352, etc. are known.

Even in these function-separated photoconductors, there has been an increasing demand for ozone resistance in recent years. When the photoconductor is actually used in a copying machine, it is exposed to ozone generated by the charger, so the photoconductor is strong. Subject to oxidation. Particularly in the case of organic photoreceptors, this effect is significant, and the materials constituting the photosensitive layer gradually oxidize and decompose, resulting in deterioration in the performance and durability of the photoreceptor. As a countermeasure, Japanese Patent Application Laid-Open No. 57-122444 and Japanese Patent Application Laid-Open No. 61-156052
It has been proposed to add an antioxidant to Photosensitive J- as shown in Japanese Patent Application Laid-Open No. 156131/1983.

However, these proposals are insufficient to prevent the deterioration of chargeability due to repeated use of the photoreceptor.

[Problem to be solved by the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photoreceptor with long life and high reliability, which prevents deterioration in chargeability due to repeated use of the photoreceptor.

(Means for Solving the Problems) According to the present invention, in an electrophotographic photoreceptor in which a photosensitive layer containing a charge-generating substance and a charge-transporting substance is provided on a conductive support, one charge-generating substance is as follows: A compound represented by Arson (1) is used, and the following - Arson (n) is used in the photosensitive layer.
An electrophotographic photoreceptor is provided, which is characterized by containing a compound represented by:

/
An aromatic ring such as a naphthalene ring, a hetero ring such as a dibenzofuran ring, or a substituted product thereof; Ar and Ar are an aromatic ring such as a benzene ring or a naphthalene ring, or a substituted product thereof;
R and R3 represent hydrogen, a lower alkyl group, a phenyl group or a substituted product thereof, and R2 represents a lower alkyl group, a carboxyl group or an ester thereof. ) Since it is possible to reliably suppress the decrease in the chargeability of the photoconductor due to R+,
To provide stable and clear copied images over a long period of time.

Specific examples of the trisazo pigment represented by the general formula (1) used in the present invention are shown below.

1<7 (wherein R4, R,, RG and R7 represent a hydrogen atom, a hydroxyl group, an alkoxy group, or an alkyl group, provided that at least one of R4, R,, R, and R7 is a hydroxyl group) ), R8 and R3 are hydrogen atoms.

Represents an alkenyl group or an alkyl group. ) The electrophotographic photoreceptor of the present invention uses the trisazo pigment represented by the general formula (1) as a charge generating substance and contains the compound represented by the general formula (II) in the photosensitive layer. Use\-CI+.

Specific examples of the compound represented by the above-mentioned (II) that can be used in the present invention include the following compounds.

IL α-tocopherol (5,7,8 trimethyl docol)
Further, in the present invention, a charge transport substance is used together with a charge generation substance, and the charge transport substance includes a hole transport substance and an electron transport substance. Examples of the hole transport substance include compounds represented by the following general formulas (1) to (12).

β-tocopherol (5,8-dimethyltocol) γ-
Tocopherol (7,8-dimethyltoco-nori, δ-tocopherol (8-methyltocol)) Among these, it is preferable to use α-tocopherol in view of the expression of effects.These compounds may be used alone or in combination of two or more. Can be used as a mixture.

L<.

[In the formula, R1 represents a methyl group, an ethyl group, a 2-hydroxyethyl group, or a 2-chloroethyl group, and R2 represents a methyl group, an ethyl group, a benzyl group, or a phenyl group,
R1 is hydrogen, chlorine, bromine, an alkyl group having 1 to 4 carbon atoms,
It represents an alkoxyl group, dialkylamino group or nitro group having 1 to 4 carbon atoms. ] [In the formula, Ar is naphthalene,
It represents anthracenes, styryl groups and substituted products thereof, pyridines, furans, and thiophenes, and R represents an alkyl group or a benzyl group. ] [In the formula, R1 is an alkyl group, a benzyl group, a phenyl group,
Represents a naphthyl group, R2 represents hydrogen, an alkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 3 carbon atoms, a dialkylamino group, a dialkylamino group, or a diarylamino group, and n represents an integer of 1 to 4. When n is 2 or more, R2 may be the same or different. R8 represents hydrogen or a methoxy group. ] represents a lkyl group, and
R2 and R3 may be bonded to each other to form a nitrogen-containing heterocycle; 6R4 may be the same or different; hydrogen;
Represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group, or a halogen. [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. ]
[In the formula, R represents an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group, or a heterocyclic group, R2,
R1 may be the same or different, and hydrogen, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a chloroalkyl group, a substituted or unsubstituted ara [wherein R is hydrogen, halogen, cyano group, carbon Ar represents an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms, R2 represents an alkyl group having 1 to 4 carbon atoms, and R3 is hydrogen.

represents a halogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a dialkylamino group, where n is 1 or 2, and when n is 2, R3 may be the same or different; R4 and R6 represent hydrogen, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a substituted or unsubstituted benzyl group. [In the formula, 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, in which these substituents are a dialkylamino group, an alkyl group, an alkoxy group,
Represents a group selected from the group consisting of a carboxy group or an ester thereof, a halogen atom, a cyano group, an aralkylamino group, an N-alkyl-N-aralkyl amino group, an amino group, a nitro group, and an acetylamino group. ] R engineering [wherein R□ represents a lower alkyl group or a benzyl group, R2 is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a 21.0 group, an amino group, a lower alkyl group, or a benzyl group represents an amino group substituted with , and n represents an integer of 1 or 2. ] p.

[In the formula, R1 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom, R2 and R3 represent an alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group, and R4 represents a hydrogen atom or a substituted or represents an unsubstituted phenyl group, and Ar represents a substituted or unsubstituted phenyl group or naphthyl group. ] RG may form a ring), m is 0, 1.2
or an integer of 3, and when m is 2 or more, R2 may be the same or different. [In the formula, n is O or an integer of 1, R represents a hydrogen atom, an alkyl group, or a substituted or unsubstituted phenyl group,
R2 and R3 represent hydrogen, a halogen atom, a substituted or unsubstituted alkyl group, or an alkoxy group, and A is above.

[In the formula, RL, R2 and R1 represent hydrogen, a lower alkyl group, a lower alkoxy group, a dialkylamino group or a halogen atom, and n represents O or 1. 〕〕9-
represents an anthryl or a substituted or unsubstituted N-alkylcarbazolyl group, where R4 is a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group , R5 and [wherein R1 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom, R2,
R3 may be the same or different and represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom. ] The compound represented by the general formula (1) includes, for example, 9-ethylcarbazol-3-aldehyde, 1-methyl-1-
Phenylhydrazone, 9-ethylcarbazole-3-aldehyde 1-benzyl-1-phenylhydrazone, 9-
ethylcarbazole-3-aldehyde], 1-diphenylhydrazone, etc.

Examples of the compound represented by general formula (2) include 4-diethylaminostyrene-β-aldehyde 1-methyl-1
-Phenylhydrazone, 4-methoxynaphthalene-1-
Examples include aldehyde 1-benzyl-1-phenylhydrazone.

Examples of the compound represented by the general formula (3) include 4-methyl-1-xybenzaldehyde 1-methyl-1-phenylhydrazone, 2,4-dimethoxybenzaldehyde 1-benzyl-1-phenylhydrazone, and 4-diethylaminobenzaldehyde. 1,1-diphenylhydrazone.

4-methoxybenzaldehyde 1-benzyl-1-(4
-methoxy)phenylhydrazone, 4-diphenylaminobenzaldehyde 1-benzyl-1-phenylhydrazone, 4-dibenzylaminobenzaldehyde-1,1
-Diphenylhydrazone, etc.

The compound represented by general formula (4) includes, for example, 1.1
-bis(4-dibenzylaminophenyl)propane, tris(4-diethylaminophenyl)methane, 1,1-
Bis(4-dibenzylaminophenyl)propane, 2.
Examples include 2'dimethyl-4,4'-bis(diethylamino)-triphenylmethane.

The compound represented by general formula (5) includes, for example, 9-(
Examples include 4-diethylaminostyryl)anthracene, 9-promo-1O-(4-diethylaminostyryl)anthracene, and the like.

The compound represented by general formula (6) includes, for example, 9-(
4-dimethylaminobenzylidene) fluorene, 3-(
Examples include 9-fluorenylidene)-9-ethylcarbazole.

The compound represented by general formula (7) includes, for example, 1.2
-bis(4-diethylaminostyryl)benzene.

1.2-Bis(2,4-dimethoxystyryl)benzene The compound represented by the general formula (8) includes, for example, 3-styryl-9-ethylcarbazole, 3-(4-methoxystyryl)-9- Examples include ethylcarbazole.

Examples of the compound represented by the general formula (9) include 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 4-ditolylaminostilbene, 1-(4-diphenylaminostyryl)naphthalene, and -(4-diethylaminostilbene). styryl) naphthylene, etc.

The compound represented by the general formula (10) includes, for example, 4'
-diphenylamino-α-phenylstilbene, 4'-
Examples include methylphenylamino-α-phenylstilbene.

The compound represented by the general formula (11) includes, for example, 1-
Phenyl-3-(4-diethylaminostyryl)-5-
(4-diethylaminophenyl)pyrazoline, 1-phenyl-3-(4-dimethylaminostyryl)-5-(4
-dimethylaminophenyl)pyrazoline, etc.

The compound represented by general formula (12) includes N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(
1,1'-biphenyl]-4,4'-diamine, N, N
'Diphenyl-N.

Examples include N'-bis(chlorophenyl)-[1,1'-biphenyl]-4°4'-diamine and 3,3'-dimethylbenzidine.

Other hole transport substances include, for example, 2,5-bis(4-diethylaminophenyl)-1,3,4-oxadiazole, 2,5-bis[4-(4-diethylaminostyryl)phenyl: -1,3,4-oxydiazole, 2-(9-ethylcarbazolyl-3-)-5-(
Oxadiazole compounds such as 4-diethylaminophenyl)-1,3,4-oxadiazole, 2-vinyl-
Examples include low molecular weight compounds such as oxazole compounds such as 4-(2-chlorophenyl)-5-(4-diethylaminophenyl)oxazole and 2-(4-diethylaminophenyl)-4-phenyloxazole. Also, poly-N
- Polymer compounds such as vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, polyvinylanthracene, pyrene formaldehyde resin, and ethylcarbazole formaldehyde resin can also be used.

Examples of electron transport substances include chloranil, bromoanil, tetracyanoethylene, tetracyanoquinone dimethane, 2,4.7-trinitro-9-fluorenone, 2,4,5.7-tetranitro-9-fluorenone, 2, 4,5.7-titranitroxanthone, 2,4゜8-1-linitrothioxanthone, 2,6.8-trinitro-411-indeno(1,2-b)thiophene-
4-one, 1,3.7-trinitrodibenzothiophene-5,5-dioxide, and the like.

The photosensitive layer of the electrophotographic photoreceptor of the present invention can be of a monodisperse type or a functionally separated type by combining a charge generating substance and a charge transporting substance.

In the case of a dispersed layer structure, a photosensitive layer in which a charge generating substance and a charge transporting substance are dispersed in a binder is provided on a conductive substrate.

In the case of a functionally separated type, a charge generation layer containing a charge generation substance and a binder is formed on the substrate, and a charge transport layer containing a charge transport substance and a binder is formed on top of the charge generation layer. charge generation layer if necessary.

The charge transport layers may be stacked in reverse. In the case of a functionally separated type, a charge transport substance may be contained in the charge generation layer. In particular, in the case of a positively charged structure, the sensitivity is improved.

Furthermore, an intermediate layer may be provided between the photosensitive layer and the substrate in order to improve adhesion and charge blocking properties. Furthermore, a protective layer may be provided on the photosensitive layer in order to improve mechanical durability such as abrasion resistance. Binders used in forming the charge generation layer, charge transport layer and dispersed photosensitive layer include polycarbonate (bisphenol A type, bisphenol A type), polyester, methacrylic resin, acrylic resin,
Polyethylene, vinyl chloride, vinyl acetate, polystyrene, phenolic resin, epoxy resin, polyurethane, vinylidene chloride, alkyd resin, silicone resin, polyvinyl carbazole, polyvinyl butyral, polyvinyl formal, polyarylate, polyacrylamide, polyamide, phenoxy resin, etc. are used. . These binders can be used alone or as a mixture of two or more.

When producing a photoreceptor using the layer structure and materials described above, there is a preferable range for the film thickness and the ratio of the materials.

(Lamination of substrate/charge generation layer/charge transport layer).

In the charge generation layer, the general formula (1) for the binder is
The proportion of the charge generating substance represented by is 20 to 500% by weight,
The film thickness is preferably 0.1 to 5 μm. In the charge transport layer, the ratio of charge transport substance to binder is 20 to 200
The weight percent and film thickness are preferably 5 to 50 μI.

In the case of (substrate/charge transport layer/stack of charge generation layer), in charge transport JM, the ratio of the charge transport material to the binder is 20 to 200% by weight, and the film thickness is 5 to 50 μm. preferable. In the charge generation layer, the general formula (r
) to the binder at a ratio of 10 to 100
It is preferable that the content is % by weight. Furthermore, it is preferable to include a charge transporting substance in the charge generation layer, which has the effect of suppressing residual potential and improving sensitivity. In this case, the charge transport material is 20 to 2
It is preferable to contain 00 parts by weight.

Further, the amount of the compound represented by the general formula (ff) of the present invention to be added to the photosensitive layer is in the case of a monofunctionally separated type.

When added to a charge transport substance, 0.0% is added to the charge transport substance.
The amount is preferably 0.001 to 50.0% by weight. When added to the charge generation layer, the amount is 0.01 to 0.01 to the charge generation substance.
It is preferably ioo,o% by weight. In the case of a dispersed type, it is preferable to add 0.001 to 50.0 weight Z to the charge transport material.

Generally, the intermediate layer provided as necessary is mainly composed of resin, and these resins are coated with photosensitive 7i5.
Considering that the resin is coated with a solvent, it is desirable that the resin has high solvent resistance to common organic solvents. Such resins include polyvinyl alcohol, casein,
Examples include water-soluble resins such as sodium polyacrylic acid, alcohol-soluble resins such as copolymerized nylon and methoxymethylated nylon, and curable resins that form a three-dimensional network structure such as polyurethane, melamine resin, phenol resin, and epoxy resin. It will be done.

Further, fine powder pigments of metal oxides such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, and indium oxide may be added to the intermediate layer to prevent moire and reduce residual potential.

Examples of the solvent or dispersion medium used in forming the charge generation layer and the charge transport layer include N,N'-dimethylformamide, acetylene, methyl ethyl ketone, cyclohexanone, benzene, and toluene.

Examples include xylene, chloroform, 1,2-dichloroethane, dichloromethane, monochlorobenzene, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and the like.

The photosensitive layer can be formed by immersing the substrate in a coating solution for the charge generation layer or charge transport layer, or by spraying the coating solution onto the substrate.

Substrates used in the electrophotographic photoreceptor of the present invention include metal drums and sheets made of aluminum, brass, stainless steel, nickel, etc., materials such as polyethylene terephthalate, polypropylene, nylon, paper, etc., on which metals such as aluminum and nickel are vapor-deposited. , or titanium oxide,
Examples include sheet-like or cylindrical substrates such as plastics and paper that are coated with a conductive substance such as tin oxide or carbon black together with a suitable binder to conductivity treatment.

〔effect〕

Since the electrophotographic photoreceptor of the present invention has the above-mentioned structure, the photoreceptor characteristics such as chargeability do not deteriorate even after repeated use over a long period of time, and therefore its practical value is extremely high.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Alcohol-soluble nylon resin (CM-8000
, nylon 6/66/610/12 copolymer, manufactured by Toshisha Co., Ltd.) 10 parts by weight.

It was dissolved in a mixed solvent consisting of 80 parts by weight of methanol and 50 parts by weight of n-butanol, 30 parts by weight of titanium oxide powder (Tiebake A-100 (manufactured by Ishihara Sangyo Co., Ltd.)) was added thereto, and dispersed in a ball mill for 12 hours. The intermediate layer coating solution was applied by dip coating and dried at 120°C for 10 minutes to a thickness of 3°0μ.
An intermediate layer of 1 was provided. Next, 5 parts by weight of butyral resin (S-LEC BL-5 (manufactured by Tanezu Chemical Industry Co., Ltd.)) was dissolved in 150 parts by weight of cyclohexanone, and exemplified compound Nα (
10 parts by weight of the trisazo pigment (67) was added and dispersed in a ball mill for 48 hours, and further 210 parts by weight of cyclohexanone was added and dispersed for 3 hours. This was taken out into a container and diluted with cyclohexanone while stirring so that the solid content was 1.5% by weight. The coating solution for charge generating JtW thus obtained was dip coated onto the intermediate layer, and the coating solution was applied at 120°C.
After drying for 10 minutes, a charge generation layer having a thickness of 0.2 tones was provided. Next, 8 parts by weight of a charge transporting substance having the following structural formula (a), 10 parts by weight of polycarbonate resin (-1300 parts by weight for Panlite)
; manufactured by Teijin Chemicals), 0.002 parts by weight of silicone oil (KF-50 manufactured by Shin-Etsu Chemical Co., Ltd.), 0.2 parts by weight of α-tocopherol, and 85 parts by weight of methylene chloride to prepare a charge transport layer coating solution. did. This was applied by dip coating onto the charge generation layer and dried at 120°C for 20 minutes to a thickness of 21 μm.
A charge transport layer was formed.

In this way, the photoreceptor of the present invention was produced.

Examples 2 to 4 α, an additive to the charge transport layer used in Example 1
A photoreceptor of the present invention was prepared in the same manner as in Example 1 except that the compounds shown in the table below were used in place of tocopherol.

Comparative Examples 1 to 3 Three types of photoreceptors for comparison were prepared in the same manner as in Example 1, except that the additives added to the charge transport layer in Example 1 were replaced with those shown in the table below.

Example 5 A photoreceptor was prepared in the same manner as in Example 1, except that α-tocopherol was added to the charge generation layer of Example 1 at a weight of 5% by weight relative to the charge generation substance, and α-tocopherol was removed from the charge transport layer. did.

The photoconductor obtained in the above manner was printed using a laser printer (
It was attached to PC-LASER-6000 (■Ricoh fjB) and evaluated. In addition, in order to evaluate the potential, the developing device was removed and a surface electrometer was attached thereto. PC-L above
The surface potential was measured at the initial stage and after printing 20,000 sheets using ASER-6000. The results are shown in Table-1.

Table-1 Example 6 8 parts by weight of the charge transport substance used in Example 1, 1 part of polycarbonate resin (Panlite-1300: manufactured by Teijin Chemicals)
0 parts by weight of silicone oil (KF-50; manufactured by Shin-Etsu Chemical Co., Ltd.) and 1 part by weight of β-tocopherol were dissolved in 85 parts by weight of methylene chloride to prepare a charge transport layer coating solution. This was applied by dip coating onto an aluminum drum with a diameter of 40 mm and a length of 255 mm.
It was dried for 5 minutes to form a charge transport layer with a thickness of 20 mm.

Next, 10 parts by weight of butyral resin [S-LEC BL-3 (manufactured by W. Mizu Kagaku Kogyo Co., Ltd.) was dissolved in 150 parts by weight of cyclohexanone, 1.2 parts by weight of the trisazo pigment of exemplified compound Nα (67) was added thereto, and ball milled. Dispersed for 48 hours at
Furthermore, 210 parts by weight of cyclohexanone and the structural formula (
3 parts by weight of the charge transport substance shown in a) was added and dispersed for 3 hours. This was taken out into a container and diluted with cyclohexanone while stirring so that the solid content was 1.0% by weight. The thus obtained charge generation layer coating liquid was spray coated onto the charge transport J and dried at 120°C for 10 minutes to form a charge generation layer with a thickness of 3 μm, thereby producing the electrophotographic photoreceptor of the present invention. did.

Comparative Example 4 A photoreceptor was prepared in the same manner as in Example 6 except that β-tocopherol was removed from the charge generation layer.

Laser printer PC-1, ASER-6000 (manufactured by Ricoh) modified from the photoreceptor obtained as above
was installed and evaluated. Is the modification content correct for each process?
fF'/If, type photoreceptor can be evaluated, and the charger, quenching lamp, and laser writing optical system can be operated even without passing paper. Furthermore, the GL imager was removed and a surface electrometer was attached to it. With the above modified laser printer,
The surface potential of the photoreceptor was measured at the initial stage and after the photoreceptor rotated 10,000 times. The results are shown in Table-2.

Table-2 Representative patent attorney pond? Ilf@Akira (and 1 other person)

Claims (1)

[Claims] (1) In an electrophotographic photoreceptor in which a photosensitive layer containing a charge-generating substance and a charge-transporting substance is provided on a conductive support, a compound represented by the following general formula (I) is used as the charge-generating substance, and An electrophotographic photoreceptor characterized in that the photosensitive layer contains a compound represented by the following general formula (II). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (However, A is ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ( Here, rings or substituted products thereof, Ar_2 and Ar_3 are aromatic rings such as benzene rings and naphthalene rings, or substituted products thereof, R_1 and R_3 are hydrogen, lower alkyl groups, phenyl groups or substituted products thereof, R_2 is lower alkyl groups, carboxyl (Represents a group or its ester.) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (II) (In the formula, R_4, R_5, R_6 and R_7 represent a hydrogen atom, a hydroxyl group, an alkoxy group, or an alkyl group (however, At least one of R_4, R_5, R_6 and R_7 is a hydroxyl group), R_8 and R_
9 represents a hydrogen atom, an alkenyl group or an alkyl group. )