JPH02118581A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve the sensitivity and durability of the photosensitive body by incorporating a specific compd. into the photosensitive layer. CONSTITUTION:The compd. expressed by formula I is incorporated into the photosensitive layer. In the formula, Cp denotes a residual coupler group and is preferably the residual group of formulas II, III. In the formulas, X denotes a hydrocarbon ring, heterocycle; Y denotes H, -CON(-R<1>)-R2, etc.; R<1> to R<3> denote H, hydrocarbon group, etc. The photosensitive body is produced by forming the photosensitive layer 2a consisting of the disazo compd. 3 expressed by the formula and a binder 4, such as polyester resin, on a conductive base 1 consisting of, for example, a polyester film deposited with Al by evaporation, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a photosensitive layer containing a disazo compound.

[Conventional technology]

So-called electrophotography, which combines photoconductive substances and electrostatic phenomena to record images, was developed by Carlson in U.S. Pat.
It originated from ``electron photography,'' which was revealed in issue 1776.

In electrophotography, a photoconductive material whose electrical resistance changes depending on the amount of light irradiation is dispersed in an insulating binder resin and coated on a support is used as a photoreceptor. . After this photoconductive material is given a sea-like surface charge by corona charging in a dark place, it loses its surface charge in accordance with the brightness value of image exposure, and an electrostatic latent image is formed.

The surface of such an electrostatic latent image is then treated with a suitable electrostatic indicator material, ie, toner, to form a visible image. The toner can be used with a dry carrier or colloidally suspended in an organic solvent and can be deposited by Coulomb force depending on the charge of the electrostatic latent image.

The attached display substance can be fixed by heat, pressure, or the like.

Further, the electrostatic latent image can be transferred to a second support (for example, paper, film, etc.), developed, and fixed.

In such electrophotography, the basic characteristics required of an electrophotographic photoreceptor are (1) ability to be charged to an appropriate potential in the dark, and (2) ability to retain charge in the dark. (3) ability to quickly dissipate charge by light irradiation;

In addition, from a practical standpoint, (4) a photoreceptor with an appropriate area can be easily manufactured, (5) it has good repeat stability,
(6) It must be durable, and (7) It must be inexpensive.

Conventionally, selenium, cadmium sulfide, zinc oxide, and the like have been widely used as photoconductive materials for electrophotographic photoreceptors. However, while these inorganic compounds have many advantages, they also have various disadvantages. For example, selenium has difficult manufacturing conditions and is expensive to manufacture. It also crystallizes easily due to temperature, humidity, fingerprints, etc., and its properties as a photoreceptor deteriorate, so it must be handled with care. It had drawbacks such as: Furthermore, cadmium sulfide has particularly poor moisture resistance, and auxiliary means such as installing a heater are required to prevent the photoreceptor from absorbing moisture. In addition, zinc oxide has problems with mechanical strength such as hardness and abrasion resistance, and since it is sensitized with dyes such as rose bengal, photobleaching of the dye due to corona charging can shorten the life of the photoreceptor. It was shrinking. These inorganic compounds contain heavy metals, and if handled incorrectly, there is a risk of developing a pollution problem.

In recent years, in order to overcome the drawbacks of these inorganic compound photoconductive materials, research and development of electrophotographic photoreceptors using various organic photoconductive compounds has been actively conducted. for example,
Poly-N-vinyl carbazole 2.4.7-IJ
Electrophotographic photoreceptor made of nitrofluorenone (U.S. Pat. No. 3,484,237), poly-N-vinylcarbazole sensitized with pyrylium salt dye (Japanese Patent Publication No. 48-25658), dye and resin A photoconductive material made of a eutectic consisting of
and so on. Compared to inorganic compound-based electrophotographic photoreceptors, such organic compound-based electrophotographic photoreceptors have the advantage of being easier to form a film, have extremely high productivity, and can provide inexpensive photoreceptors. ing. However, with respect to photoconductive polymers such as EVA and poly-N-vinylcarbazole, polymers alone have poor film properties, flexibility, adhesion, etc., and in order to improve these drawbacks, plastic material,
A binder or the like is added, but this causes problems such as a decrease in sensitivity and an increase in residual potential.

In addition, organic compound-based low-molecular photoconductive compounds have a wide range of binders to choose from, and if an appropriate polymer is selected,
Although it is possible to produce products with excellent mechanical properties such as filmability and adhesiveness, on the other hand, they do not fully satisfy the requirements for electrophotographic photoreceptors such as photosensitivity and repeatability.

[Problems to be solved by the present invention]

The problem to be solved by the present invention is to overcome the drawbacks of conventional inorganic compound-based electrophotographic photoreceptors, improve the drawbacks of organic compound-based electrophotographic photoreceptors that have been proposed so far, and put them into practical use. An object of the present invention is to provide an electrophotographic photoreceptor having extremely high sensitivity and durability.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention can be realized by the general formula (1), but especially by the general formula (II) and the general formula (III).
) Provided is an electrophotographic photoreceptor containing a compound represented by the general formula (■) (wherein Cp represents all coupler residues).

The Kab2-residue in the compound represented by the general formula (1) may be selected from known Kab2-components or the Kab2-residue of the general formula (
V) (In the formula, X represents a hydrocarbon group or a heterocycle which may have a substituent, Y is a hydrogen atom, and R2 and R3 each independently have a hydrogen atom or a substituent. (R1 and R2 may mutually form a ring.) A coupler residue represented by the following formula is preferable.

Specific examples of RR and R3 in the Kab2-residues of the above general formulas (n), (I[I), (fV) and (V) include:
Methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, isopropyl group, isobutyl group, inamyl group, isohexyl group, neopentyl group, t@rt
- Alkyl groups having 1 to 20 carbon atoms such as butyl groups; aromatic hydrocarbon groups such as phenyl groups and naphthyl groups; aromatic heterocyclic groups such as pyridyl groups, carbazolyl groups, and benzotriazolyl groups, etc. .

When R, R and R are substituted alkyl groups, examples of the substituent include a halogen atom, a nitro atom, a cyano group,
Examples include a hydroxyl group, a substituted hydroxyl group, a thiol group, a substituted thiol group, an amino group, a substituted amino group, an aryl group, and the like. Specific examples of the substituted alkyl group, which may be a substituted alkyl group having two or more of these substituents, include a chloromethyl group, a trifluoromethyl group, and a chloromethyl group such as a 2-bromoethyl group; a nitromethyl group; Nitroalkyl group such as 3-nitropropyl group; Cyanoalkyl group such as cyanomethyl group, 2-cyanoethyl group; Hydroxymethyl group, 2-hydroxyethyl group,
Hydroxydialkyl groups such as 2-hydroxypropyl group and 3-hydroxypropyl group; methoxymethyl group, 2-hydroxypropyl group;
Substituted hydroxyalkyl groups such as methoxyethyl group, ethoxymethyl group, phenoxymethyl group; Thiohydroxyalkyl group such as thiohydroxymethyl group, 2-thiohydroxyethyl group: Substituted thiohydroxy group such as methylthiomethyl group, 2-methylthioethyl group Alkyl group Aminoalkyl group such as niaminomethyl group, 2-aminoethyl group; methylaminomethyl group, ethylaminemethyl group, dimethylaminomethyl group%2-(dimethylamino)ethyl group, phenylaminomethyl group, diphenylaminomethyl group Examples include substituted aminoalkyl groups.

R% When R and R are a substituted aromatic hydrocarbon group or a substituted aromatic heterocyclic group, the substituents include an alkyl group, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted hydroxyl group, a thiol group, Examples include a substituted thiol group, an amino group, and a substituted amino group. These substituents are 2
It may be a substituted aromatic hydrocarbon group or a substituted aromatic heterocyclic group having at least 1 or more substituted aromatic hydrocarbon groups.

Specific examples when R, R and R are substituted phenyl groups include tolyl group, ethylphenyl group, kyalkylphenyl group; chlorophenylated phenyl group such as chlorophenyl group, fromophenyl group; nitrophenyl group; cyanophenyl group. group; hydroxyphenyl group; substituted hydroxyphenyl group such as methoxyphenyl group, ethoxyphenyl group; thiohydroxyphenyl group; methylthiophenyl group,
Examples include substituted thiophenyl groups such as ethylthiophenyl groups, niaminophenyl groups; substituted aminophenyl groups such as methylaminophenyl groups, dimethylaminophenyl groups, phenylamino 7-enyl groups, and diphenylaminophenyl groups.

Specific examples when R, R and R are substituted condensed aromatic hydrocarbon groups include alkylnaphthyl groups such as methylnaphthyl group and ethylnaphthyl group; halogen-substituted 7-tyl groups such as chloronaphthyl group and bromonaphthyl group; ; Hydroxynaphthyl group; Substituted hydroxynaphthyl group such as methoxynaphthyl group and ethoxynaphthyl group; Thiohydroxynaphthyl group: Substituted thionaphthyl group such as ethylthionaphthyl group and ethylthionaphthyl group; Aminonaphthyl group; Methylaminonaphthyl group, dimethylamino Examples include substituted aminonaphthyl groups such as naphthyl group, phenylaminonaphthyl group, and diphenylaminonaphthyl group.

Specific examples when R%R and R are substituted aromatic heterocyclic groups, especially KM-substituted benzothiazolyl groups, include alkylbenzothiazolyl groups such as methylbenzothiazolyl group and ethylbenzothiazolyl group: chloro Halogen-substituted benzothiazolyl groups such as benzothiazolyl group and bromobenzothiazolyl group; nitrobenzothiazolyl group; cyanobenzothiazolyl group; hydroxybenzothiazolyl group; methoxybenzothiazolyl group, ethoxybenzothia Substituted hydroxybenzothiazolyl group such as zolyl group; thiohydroxybenzothiazolyl group: methylthiobenzothiazolyl group,
Substituted thiobenzothiazolyl group such as ethylthiobenzothiazolyl group; aminobenzothiazolyl group; methylaminobenzothiazolyl group, dimethylaminobenzothiazolyl group, phenylaminobenzothiazolyl group, diphenylamino Examples include substituted aminobenzothiazolyl groups such as benzothiazolyl groups.

The disazo compound represented by the general formula (1) according to the present invention can be produced by a conventionally known method. for example,
"Journal Op Chemical Society" 1371
(1963), 2-methyl-4,5-
By reacting bis(4-nitrophenyl)oxazole with bromine in an acetic acid solvent, 4,4'-dinitrobenzyl represented by the following formula CM) is produced.

Furthermore, the compound of formula (Vl) is reduced with zinc in the presence of calcium chloride in ethanol to produce 4,4'-diaminobenzyl represented by the following formula (■).

Next, the compound represented by the formula (■) is diazotized by a conventional method and coupled with the coupler Cp in the presence of an alkali, or the diazonium salt of the compound represented by the formula (■) is converted into a borohydrofluoride or a zinc salt. Once isolated as a salt, the compound of formula (1) can be easily converted into a compound of formula (1) by coupling with a coupler in the presence of an alkali in a suitable solvent, for example, an inert organic solvent such as N,N'-dimethylformamide or dimethyl sulfoxide. compounds can be manufactured.

Specific examples of the disazo compounds of the above-mentioned Monna (I) that can be used in the present invention are shown in Tables M1 to 6 in terms of structural formulas.

The electrophotographic photoreceptor of the present invention can have various structures. Examples are shown in Figures 1-4. The photoreceptor shown in FIG. 1 has a photosensitive layer (2a) formed by dispersing an azo compound (3) in a binder (4) on a conductive support (1). The photoreceptor shown in FIG. 2 has a photosensitive layer (2b) formed by dispersing an azo compound (3) in a charge transport medium consisting of a charge transport substance (5) and a binder on a conductive support. The photoreceptor shown in FIGS. 3 and 4 has a photosensitive layer (2c) consisting of a charge carrier generation layer (6) mainly composed of an azo compound (3) and a charge transport layer (7) composed of a charge transport substance and a binder. or (2d) respectively. In the case of FIG. 1, the azo compound (3) performs both the generation of charge carriers necessary for light attenuation and charge transport. In the case of the photoreceptor of FIG. 2, the charge transport material together with the binder forms the charge transport medium (5), while the azo compound (3) acts as a charge carrier generating material.

Although this charge transport medium (5) does not have the ability to generate charge carriers like the azo compound (5), it has the ability to accept and transport charge carriers generated from the azo compound. That is, in the photoreceptor shown in FIG. 2, the generation of charge carriers necessary for light attenuation is carried out by the azo compound (3), while the transport of charge carriers is carried out mainly by the charge transport medium (5). In the case of the photoreceptors shown in Figures 83 and 4, the azo compound (3) contained in the charge carrier generation layer (6) generates charge carriers, while the charge transport layer (7) does not allow injection of charge carriers. Receive and transport the goods. That is, the mechanism of action is the same as that of the photoreceptor shown in FIG. 2, in which the generation of charge carriers necessary for light attenuation is carried out by an azo compound, and the transport of charge carriers is carried out by a charge transport medium.

The photoreceptor shown in FIG. 1 can be manufactured by dispersing an azo compound in a binder solution, coating this dispersion on a conductive support, and drying it.

The photoreceptor shown in FIG. 2 can be manufactured by dispersing an azo compound in a solution containing a charge transporting substance and a binder, coating this dispersion on a conductive support, and drying it. The photoreceptor shown in FIG. 3 can be obtained by vacuum-depositing an azo compound on a conductive support, or by applying a dispersion obtained by dispersing fine particles of an azo compound in a solvent or a binder solution, and drying it. It can be manufactured by applying a solution containing a charge transporting substance and a binder thereon and drying it. The photoreceptor shown in Fig. 4 is produced by coating a conductive support with a solution containing a charge transport substance and a binder and drying it, and then vacuum-depositing an azo compound thereon, or by depositing fine particles of an azo compound in a solvent or a binder solution. A can be produced by coating and drying the dispersion obtained by dispersing the liquid in the liquid.

The thickness of the photosensitive layer of these photoreceptors is 3 to 50 μm, preferably 5 to 20 μm in the case of the photoreceptors shown in FIGS.
It is. In the case of the photoreceptor shown in FIGS. 3 and 4, the thickness of the charge carrier generation layer is 5 μm or less, preferably 0.01 to 5 μm.
The thickness of the charge transport layer is 3 to 50 μm, preferably 5 to 20 μm.

Further, in the photoreceptor shown in FIG. 1, the proportion of the azo compound in the photosensitive layer is 10 to 70% by weight, preferably 30 to 50% by weight based on the photosensitive layer. In the photoreceptor shown in Figure 2,
The proportion of the azo compound in the photosensitive layer is 1 to 50% by weight, preferably 3 to 30% by weight, and the proportion of the charge transport material is 10 to 90% by weight, preferably 10 to 60% by weight. The ratio of the charge transport substance in the charge transport medium in the photoreceptor shown in the FAS diagram and in FIG. 4 is 10 to 95, preferably 10
~60 weight class.

Examples of the conductive support used in the photoreceptor of the present invention include aluminum, copper, zinc, stainless steel, chromium,
Metal plates and drums are made of metals or alloys such as titanium, nickel, molybdenum, vanadium, indium, gold, and platinum, or conductive polymers, conductive compounds such as indium oxide, aluminum, palladium, gold, etc. Examples include coating metal or alloy, vapor deposition, laminating paper, plastic film, etc.

As the binder, it is preferable to use a hydrophobic polymer capable of forming an electrically insulating film. Examples of such high molecular weight polymers include polycarbonate,
Polyester, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene/, polyvinyl acetate, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride
Vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole, polyvinyl buty''s Examples include, but are not limited to, polyvinyl formal and polysulfone.

These binders can be used alone or as a mixture of two or more.

Additionally, additives such as plasticizers, sensitizers, surface modifiers, etc. can also be used together with these binders.

Examples of plasticizers include biphenyl, chlorinated biphenyl, 0-terphel, p-terphenyl, dibutyl phthalate, diethylene glycol phthalate, dioctyl phthalate, triphenyl phosphoric acid, methylnaphthalene, benzophenone, chlorinated paraffin, polypropylene, polystyrene, and various fluorohydrocarbons. etc.

Examples of the sensitizer include chloranil, tetracyanoethylene, methyl violet, rhodamine B1 cyanine dye, merocyanine dye, biryllium dye, and thiavirilicum dye.

Examples of the surface modifier include silicone oil, 7-tsuso resin, and the like.

Furthermore, in the present invention, in order to improve the adhesion between the conductive support and the photosensitive layer, and to prevent the injection of free charges from the conductive support to the photosensitive layer, Between,
An adhesive layer or barrier layer can also be provided as required. Materials used for these layers include, in addition to the polymer compound used for the binder, casein, gelatin, polyvinyl alcohol, ethyl cellulose, nitrocellulose, polyvinyl butyral, phenolic resin, polyamide, carboxy-methylcellulose vinylisoychloride-based polymer latex. , styrene-butadiene polymer latex, polyurethane, gelatin, aluminum oxide, tin oxide, titanium oxide, and the like.

In addition, charge transport materials are generally classified into two types: compounds that transport electrons and compounds that transport holes.
Both can be used in the electrophotographic photoreceptor of the present invention.

Examples of the electron transporting substance include chloranil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4.7-)linitro-9-fluorenone,
2.4,5.7-tetranitro-9-fluorenone, 9
-dicyanomethylene-21417-17 ditrofluorenone, 9-dicyanomethylene vy -214p5.7-
Tetranitrofluorenone, 2,4.5.7-tetranitroxanthone, 2.4.8- trinidrothioxanthone, tetranitrocarbasol chloranil, 2.3-
Dichloro-5,6-dicyatupenzoquinone, 2.4.7
- Trinitro-9,1O-7 enanthrenequinone, tetrachlorophthalic anhydride, etc. can be mentioned.

Examples of the hole transport substance include low molecular weight compounds such as evapyrene, N-ethylcarbazole, N-isopropylcarbazole, N-phenylcarbazole, or N-methyl-2-phenylhydrazino-3-methylitene-9-ethylcarbazole. , N,N-diphenylhydrazino-3-
Methylidene-9-ethylcarbazole, p-N,N-dimethylaminobenzaldehyde diphenylhydrazone 5
Hydrazones such as PN, N-diethylaminobenzaldehyde diphenylhydrazone, p-N, N-diphenylaminobenzaldehyde diphenylhydrazone, 2.
5-bis(p-diethylaminophenyl)-1,3,4
-Oxadiazole, pyrazolines such as l-phenylene/L/-3-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, triphenylamine, N, N, N[N'-tetraphenyl -1,f-biphenyl-4,4'-diamine, N,N'-diphenyl-N,N'-bis(3-methyl7enyl) -x,r-
Examples include biphenyl-4,4'-diamine. or,
Examples of the polymer compound include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole,
Examples include polyvinylpyrene, polyvinylanthracene, polyvinylacridine, pyrene-formaldehyde resin, ethylcarbazole-formaldehyde resin, triphenylmethane polymer, and the like.

The charge transport materials are not limited to those described here, and can be used alone or in combination of two or more kinds.

When a laminated photoreceptor is formed by coating, the solvent that dissolves the binder varies depending on the type of binder, but it is preferably selected from those that do not dissolve the lower H5. Specific examples of organic solvents include alcohols such as methanol, ethanol, and n-propanol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; N,N-dimethylformamide, N,N
- Amides such as dimethylacetamide; ethers such as tetrahydrofuran, dioxane, methyl cellosolve;
Esters such as methyl acetate and ethyl acetate; sulfoxides and sulfones such as dimethyl sulfoxide and sulfolane; aliphatic and rogenated hydrocarbons such as methine chloride/, chloroform, carbon tetrachloride, and trichloroethane; benzene,
C) Aromatics such as toluene, xylene, monochlorobenzene, dichlorobenzene, etc.

As the coating method, for example, a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a wire bar coating method, a flade coating method, a roller coating method, a curtain coating method, and the like can be used.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the Examples. still,
In the examples, "parts" indicate "parts by weight." In addition, the dimensional value of the disazo compound means /l in Tables 1 to 6.

Example 1 10 parts of a polyester resin (trade name "Vylon 200" manufactured by Toyobo Co., Ltd.), 10 parts of an AI disazo compound, and 80 parts of tetrahydrofuran were pulverized and mixed in a vibrating mill, and the resulting dispersion was coated on an aluminum-deposited Ll polyester film. The photoreceptor was coated with a wire bar and dried to obtain a photoreceptor having a photoreceptor layer having a thickness of about 10μ and having the structure shown in the ninth construction drawing. Next, an electrostatic copying paper tester @ Model 5P-4 was applied to the photosensitive layer surface of this photoreceptor.
28 (manufactured by Kawaguchi Electric Seisakusho Co., Ltd.), the photoreceptor was first charged by corona discharge at an applied voltage of -6 kV in a dark place.
Leave it in the dark for 0 seconds, then turn on the tungsten lamp.
The photosensitive layer is irradiated with light so that the surface has an illumination intensity of 5 lux, and the time required for the surface potential to decrease to the ring of the surface potential after being left in a dark place for 0 seconds is measured, and the photosensitivity E, ( When the lux/second) was calculated, it was EH-16.5 lux/second.

Example 2 3 parts of polyester resin (same product as Example 1), 2.4.
7-) 3 parts of Rinitro 9-fluorenone, 0.6 parts of the disazo compound of Ya 1, and 30 parts of tetrahydrofuran were pulverized and mixed in a ball mill, and the resulting dispersion was placed on a polyester film coated with aluminum using a wire bar. After coating and drying, a photoreceptor having the structure shown in FIG. 2 having a photosensitive layer having a thickness of about 9 μm was prepared. Next, the sensitivity of this photoreceptor was measured according to Example 1 and was found to be 9 to -8 flux seconds.

Example 3 3 parts of ml of disazo compound was added to phenoxy resin (trade name:
PKHHJ (manufactured by Union Carbide) was dissolved in 75 parts of dioxane and pulverized and mixed using a vibrating mill.The resulting dispersion was coated onto an aluminum-deposited polyester film using a wire bar and dried. A charge generation layer having a thickness of 1 μm was formed. On this charge generation layer, 5 parts of p-diethylaminebenzaldehyde-diphenylhydrazone and a polycarbonate resin (trade name "Panlite L-
A solution prepared by dissolving 5 parts of 1250WJ (manufactured by Teijin Kasei Co., Ltd.) in 65 parts of methylene chloride was coated using a wire bar and dried to form a charge transport layer with a thickness of 10 μm to obtain a photoreceptor having the structure shown in FIG. 3. The sensitivity of the thus produced photoreceptor was measured according to Example 1 and found to be E) S = 2.0 lux·sec.

Examples 4 to 20 Photoreceptors having the structure shown in FIG. 3 were prepared in the same manner as in Example 3, except that the disazo compounds shown in Table 7 below were used in place of the disazo compounds in The sensitivity was measured and the results listed in the same table were obtained.

Example 21 in Table 7 A third experiment was carried out in the same manner as in Example 3, except that all of N-ethylcarbazole-3-methylidene-N-aminoindoline was used instead of p-diethylaminobenzaldehyde-diphenylhydrazone as the charge transport material. A photoreceptor having the structure shown in the figure was prepared, and its sensitivity was measured according to Example 1, and the sensitivity was found to be -3.5 lux·sec.

Examples 22 to 40 The disazo compounds shown in Table 8 below were used in place of the disazo compound in 41, and N-ethylcarbazole-3-methylidene-N- was used in place of p-diethylaminobenzaldehyde-diphenylhydrazone as the charge transport substance. The third step was carried out in the same manner as in Example 3 except that aminoindoline was used.
A photoreceptor having the structure shown in the figure was prepared, and the sensitivity was measured according to Example 1, and the results listed in Table 8 were obtained.

/ Example 41 The third example was prepared in the same manner as in Example 3 except that N-ethylcarbazo)v-3-methylidene-N-aminotetrahydroquinoline was used instead of p-diethylaminobenzaldehyde-diphenylhydrazone as the charge transport material. A photoreceptor having the structure shown in the figure was prepared, and the sensitivity was measured according to Example 1, and the sensitivity was Ey2-4.0 lux·sec.

Examples 42 to 60 The disazo compounds shown in Table 9 below were used in place of the disazo compound in A1, and N-ethylcarbasol-3-methylidene was used in place of p-diethylaminobenzaldehyde-diphenylubicin as the charge transport substance. A photoreceptor having the structure shown in FIG. 3 was prepared in the same manner as in Example 3 except that -N-aminotetrahydroquinoline was used, and the sensitivity was measured in accordance with Example 1, and the results listed in the table were obtained. .

/ / Table 8 Table 9 Example 61 3 parts of polycarbonate resin (same product as Example 3), p''
A solution of 3 parts of diethylaminobenzaldehyde phenylhydrazone dissolved in 35 parts of tetrahydrofuran was applied onto a polyester film coated with aluminum using a wire spar and dried to form a charge transport layer with a thickness of about 10 μm.

Next, the paint used to form the charge generation layer in Example 3 was applied onto the charge transport layer using a wire bar and dried to form a charge generation layer with a thickness of about 0.8 μm. A photoreceptor was obtained. The sensitivity of the nine photoreceptors thus produced was measured in accordance with Example 1 by performing corona discharge at an applied voltage of +6 kV, and found to be 8 wheels -2.8 lux·sec.

〔Effect of the invention〕

Since the electrophotographic photoreceptor of the present invention has excellent durability and high sensitivity, it can be widely used in RPC copying machines and the like.

[Brief explanation of the drawing]

1 to 4 are enlarged partial cross-sectional views of the electrophotographic photoreceptor according to the present invention. 1... Conductive support, 2ma2be2e*2a... Photosensitive layer, 3° disazo compound, 4... Binder 5... Charge transport material, 6... Charge carrier generation layer, 7... Charge transport layer.

Claims (1)

[Claims] 1. Electrophotography characterized by containing a compound represented by the general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, Cp represents a coupler residue.) Photoreceptor for use. 2. Cp is general formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula (III) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula (IV) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or General formula (V) ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, X represents a hydrocarbon ring or heterocycle that may have a substituent, Y is a hydrogen atom, ▲ Numerical formula, chemical formula ,
There are tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. Alternatively, it represents a heterocyclic group, and R^1 and R^2 may mutually form a ring. 2. The electrophotographic photoreceptor according to claim 1, which is a coupler residue represented by the following formula.