JPH01142647A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To realize high sensitivity and low residual potential of an electrophotographic sensitive body by incorporating a specified compd. into a photosensitive layer of the electrophotographic sensitive body. CONSTITUTION:A photosensitive layer is formed on an electroconductive base material of an electrophotographic sensitive body, and the photosensitive layer contains a compd. expressed by formula I, wherein each R<1>-R<6> is H atom., lower alkyl group, etc.; each l, m, n and o is an integer 1-5; at least either one of p and q is an integer 2-4. A single benzidine deriv. or a mixture of >=2 kinds thereof is used. Since the benzidine deriv. has high symmetry of molecular structure and good compatibility with a binder resin, moreover, small dependency of the drift mobility on electric field strength, special effects in providing high sensitivity and low residual potential on an electrophotographic sensitive body are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an electrophotographic photoreceptor suitably used in an image forming apparatus such as a copying machine.

<Problems to be solved by conventional technology and inventions> In recent years,
As an electrophotographic photoreceptor in image forming devices such as copying machines, this photoreceptor has a high degree of freedom in functional design, and includes a charge-generating material that generates charges when irradiated with light and a charge-transporting material that transports the generated charges. For example, a single-layer photosensitive layer containing a charge generating material, a charge transporting material, and a binder resin, or a charge generating layer containing the above charge generating material, a charge transporting material, and a binder resin. A functionally separated electrophotographic photoreceptor has been proposed, which includes a laminated photosensitive layer in which a charge transport layer and a charge transport layer are laminated.

Further, when forming a copy image using an electrophotographic photoreceptor, the Carlson process is widely used. This Carlson process consists of a charging process in which a photoreceptor is uniformly charged by corona discharge, an exposure process in which an original image is exposed to the charged photoreceptor to form an electrostatic latent image corresponding to the original image.
A development process in which an electrostatic latent image is developed with a developer containing toner to form a toner image, a transfer process in which the toner image is transferred to a base material such as paper, and a toner image transferred to the base material is fixed. The basic steps include a fixing process and a cleaning process to remove toner remaining on the photoreceptor after the transfer process. In order to form high-quality images in the Carlson process, the electrophotographic photoreceptor must be , they are required to have excellent charging properties and photosensitive properties, and to have a low residual potential after exposure.

On the other hand, in the functionally separated electrophotographic photoreceptor, the characteristics of the charge generating material and the charge transporting material greatly affect the electrical characteristics and photosensitive characteristics of the photoreceptor, and if the characteristics of each of the above materials are insufficient, the photoreceptor The electrical and photosensitive properties of the photosensitive material deteriorate, resulting in a reduction in the quality of the reproduced image.

In view of the above points, benzidine derivatives, such as 4,4'-bis[N-phenyl-N-(3-
methylphenyl)aminococyphenyl, 4,4'-bis[N,N-di(4-methylphenyl)amino]-2,2
' -dimethyldiphenyl, 4,4'-bis[N,N-
di(4-methylphenyl)amino]-3,3'-dimethyldiphenyl, etc. have been proposed (Japanese Patent Application Laid-Open No. 57-14
No. 4558, JP-A-61-62038, US Pat. No. 4,047,948, US Pat. No. 45364
57 specification, JP-A-61-124949, JP-A-81-134354, JP-A-61-134355, JP-A-82-112164).

A photoreceptor provided with a photosensitive layer containing the above-mentioned benzidine derivative generally has superior electrical properties and photosensitive properties compared to photoreceptors containing other charge transport materials.

However, the above-mentioned benzidine derivatives do not have sufficient compatibility with the binder resin, have low electron donating properties, and do not yet have sufficient charge transport ability. However, there is a problem that the residual potential is large.

<Object of the Invention> The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide an electrophotographic photoreceptor that has excellent compatibility with a binder resin, charging characteristics, and photosensitivity characteristics, and has a small residual potential. With the goal.

Means and Effects for Solving the Problems In order to achieve the above object, the electrophotographic photoreceptor of the present invention has a photoreceptor layer formed on a conductive base material, in which the photoreceptor layer has the following: - It is characterized by containing a compound represented by formula (1).

(In the formula, R'% R2, R3, R4, R5 and R6
are the same or different, a hydrogen atom, a lower alkyl group,
Indicates a lower alkoxy group or )\rogen atom. 4%
m, , n and 0 represent integers of 1 to 5, and at least one of p and q represents an integer of 2 to 4. however,
It is assumed that R5 and R6 are not hydrogen atoms at the same time. ) The present invention will be explained in detail below.

In the electrophotographic photoreceptor of the present invention, a photosensitive layer containing a compound represented by the above general formula (1) is formed on a conductive base material.

The above-mentioned conductive base material may be in the form of a sheet or a drum, and either the base material itself has conductivity or the surface of the base material has conductivity and has sufficient mechanical strength when used. Preferably. As the conductive base material, various conductive materials can be used, such as aluminum, copper,
tin, platinum, gold, silver, vanadium, molybdenum, chromium,
Examples include simple metals such as cadmium, titanium, nickel, palladium, indium, stainless steel, and brass, plastic materials on which the above metals are vapor-deposited or laminated, and glass coated with aluminum iodide, tin oxide, indium oxide, etc. Ru. Among the conductive substrates mentioned above, aluminum, especially aluminum crystal grains, are not present on the surface, preventing the occurrence of black spots, pinholes, etc. in copied images, etc., and a photosensitive layer containing a benzidine derivative, etc. In order to improve adhesion to the base material, alumite-treated aluminum is used, especially the thickness of the alumite-treated layer is 5 to 12 mm.
Anodized aluminum having a surface roughness of 1.5S or less is preferable.

In the compound represented by general formula (1) contained in the photosensitive layer, the lower alkyl group includes methyl, ethyl,
propyl, isopropyl, butyl, isobutyl, ter
1-6 carbon atoms such as t-butyl, pentyl, hexyl group, etc.
An example is an alkyl group. Among the lower alkyl groups mentioned above, alkyl groups having 1 to 4 carbon atoms are preferred.

Examples of lower alkoxy groups include alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, imbutoxy, tert-butoxy, pentyloxy, and hexyloxy groups. Among the lower alkoxy groups mentioned above, alkoxy groups having 1 to 4 carbon atoms are preferred.

Furthermore, examples of the halogen atom include fluorine, chlorine, bromine, and iodine atoms.

The substituents R', R", R', R', R' and R6 may be substituted at appropriate positions on the benzene ring or biphenyl skeleton. At least one of p and q is 2-2. 4, p and/or q
When is 2, compounds in which R5 and/or R6 are substituted at the 2,5-position or the 2', 5'-position of the biphenyl skeleton are preferred. Also, p and/or q is 3
When R5 and/or R6 are substituted at the 2°3.6-position or the 2', 3', or 6'-position of the biphenyl skeleton, compounds are preferred. Particularly preferred are benzidine derivatives in which both p and q are 2, and both R5 and R6 are substituted at the 2,5-position and the 2',5'-position of the biphenyl skeleton.

Among the benzidine derivatives represented by the above general formula (1),
Preferred compounds include, for example, the benzidine derivatives shown in the table below, which may be used singly or in combination of two or more.

In addition, the above benzidine derivative has good molecular symmetry,
It does not cause any isomerization reactions when irradiated with light, has excellent photostability, has excellent compatibility with the binder resin, has high drift mobility, and has low dependence of drift mobility on electric field strength. Therefore, an electrophotographic photoreceptor equipped with a photosensitive layer containing the above-mentioned benzidine derivative has good charging properties, high sensitivity, low residual potential, and can produce high-quality images without fog.

The compound represented by the general formula (1) above can be obtained by various methods, for example, by simultaneously or simultaneously treating the compound represented by the following general formula 0 and the compounds represented by general formulas (3) to (6). It can be produced by sequential reactions.

(In the formula, R1, R2, R3, R4, R5, R6, fl
-m % n % Olp and q are the same as above. X represents a halogen atom such as iodine. ) A compound represented by the above general formula (2) and general formulas (3) to (
The reaction with the compound represented by 6) is usually carried out in an organic solvent, and any solvent can be used as long as it does not adversely affect this reaction, such as nitrobenzene, dichlorobenzene, quinoline, Examples include organic solvents such as N,N-dimethylformamide, N-methylpyrrolidone, and dimethylsulfoxide. The reaction is usually
Copper powder, catalysts such as copper oxide copper halide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate,
It is carried out at a temperature of 150 to 250°C in the presence of a basic substance such as sodium hydrogen carbonate or potassium hydrogen carbonate.

Furthermore, in the compound represented by the general formula (1), a compound in which the substitution positions of the substituents R', R2, R3, and R4 are controlled is, for example, a compound represented by the following general formula (7). After obtaining the compound represented by general formula (8) by the reaction with the compound represented by general formula (3) (5), the compound represented by general formula (8) is then hydrolyzed to remove After acylation to obtain a compound represented by general formula (9),
Furthermore, it can be produced by reacting with a compound represented by general formula (4) (6).

(7) Gl (5) (wherein, R
7 and R6 represent lower alkyl groups, R', R''
, R3, R', R5, R6, J, m.

n s O% pSQ and X are the same as above. ) The reaction between the compound represented by the above general formula σ) and the compound represented by the general formulas (3) (5) is the reaction between the compound represented by the above general formula (2) and the general formulas (3) to (6). ) can be carried out in the same manner as the reaction with the compound represented by. The deacylation reaction of the compound represented by the general formula (8) can be carried out by a conventional method in the presence of a basic catalyst. Furthermore, the reaction between the compound represented by the above general formula ○) and the compound represented by the general formulas (4) and (6) is the reaction between the compound represented by the above general formula (■) and the general formulas (3) to (6). It can be carried out in the same manner as the reaction with the compound represented by.

In addition, in the compound represented by the general formula (1), the compound in which the substituents R1, R2, R3, R4, R5 and R6 are halogen atoms can be prepared by halogenating the reaction product after the above reaction. May be manufactured.

After the reaction is complete, the reaction mixture is concentrated and purified without purification.
Alternatively, it can be easily separated and purified by conventional means such as recrystallization, solvent extraction, and column chromatography.

In addition, as mentioned above, the compound represented by the general formula (1) is
A photoreceptor with excellent charge transport properties, high sensitivity, and low residual potential can be obtained, but if necessary, it may be used in combination with other charge transport materials as long as the charging characteristics, photosensitivity characteristics, etc. are not impaired. Examples of the other charge transport materials include tetracyanoethylene, fluorenone compounds such as 2°4.7-dolinitro-9-fluorenone, and nitrated compounds such as 2,4.8-)-linitrothioxanthone and dinitroanthracene. , succinic anhydride, maleic anhydride, dibromomaleic anhydride, oxadiazole compounds such as 2,5-di(4-dimethylaminophenyl)-1,3,4-oxadiazole, 9-(4-diethylamino Styril)
Styryl compounds such as anthracene, carbazole compounds such as polyvinylcarbazole, 1-phenyl-3-
Pyrazoline compounds such as (p-dimethylaminophenyl)pyrazoline, amine derivatives such as 4,4',4'-tris(4-diethylaminophenyl)triphenylamine, 1,1-diphenyl-4,4-bis(4 Conjugated compounds such as -dimethylaminophenyl)-1,3-butadiene, hydrazone compounds such as 4-(N,N-diethylamino)benzaldehyde N,N-diphenylhydrazone, indole compounds, oxazole compounds, isoxazole compounds compounds, thiazole compounds,
Examples include nitrogen-containing cyclic compounds such as thiadiazole compounds, imidazole compounds, pyrazole compounds, and triazole compounds, and fused polycyclic compounds. Note that the photoconductive polymer as the charge transporting material, such as poly-N-vinylcarbazole, may be used as a binder resin.

The photosensitive layer containing the compound represented by the general formula (1) above may be a single-layer photosensitive layer containing a charge generating material, the compound represented by the above general formula (1), and a binder resin, or at least a charge generating material. The photosensitive layer may be any of a laminated type photosensitive layer in which a charge generation layer containing the above compound and a charge transport layer containing the compound represented by the above general formula (1) and a binder resin are laminated. Also,
In the laminated photosensitive layer, the charge transport layer may be formed on the charge generation layer, or conversely, the charge generation layer may be formed on the charge transport layer.

Examples of the charge generating material include selenium, selenium-
Tellurium, amorphous silicon, pyrylium salts, azo compounds, disazo compounds, phthalocyanine compounds,
Examples include anthanthrone compounds, perylene compounds, indigo compounds, triphenylmethane compounds, threne compounds, toluidine compounds, pyrazoline compounds, and quinacridone compounds. The above charge generating material is
One or more types are used.

The charge generating material described above can be selected as appropriate, but in order to increase the spectral sensitivity, phthalocyanine compounds,
For example, among aluminum phthalocyanine, copper phthalocyanine, and vanadyl phthalocyanine having various crystal forms such as α type, β type, and γ type, those containing at least metal-free phthalocyanine and/or titanyl phthalocyanine are preferred. The above phthalocyanine compound may have an appropriate particle size, but the average particle size is 0°1.
Preferably, the thickness is less than μm. When the average particle size of the metal-free phthalocyanine exceeds 0.1 μm, the sensitivity of the photoreceptor decreases.

In addition, various binder resins can be used, such as styrene polymers, acrylic polymers, styrene-acrylic copolymers, polyethylene, ethylene-vinyl acetate copolymers, chlorinated polyethylene, polypropylene, and ionomers. Olefin polymers such as polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyester, alkyd resin, polyamide, polyurethane, epoxy resin, polycarbonate, polyarylate, polysulfone, diallyl phthalate resin, silicone resin, ketone resin, polyvinyl Butyral resin, polyether resin, phenol resin, photocurable resin such as epoxy acrylate, etc.
Various polymers are exemplified. One or more types of the above-mentioned binder resins may be used.

In addition, the photosensitive layer includes terphenyl, halonaphthoquinones,
Conventionally known sensitizers such as acenaphthylene, 9-(N,N
It may contain various additives such as fluorene compounds such as -diphenylhydrazino)fluorene and 9-carbazolyliminofluorene, deterioration inhibitors such as plasticizers, antioxidants, and ultraviolet absorbers.

Charge generating material in the single-layer photosensitive layer and general formula (1)
The ratio of the compound represented by the formula to the binder resin is not particularly limited and can be appropriately selected depending on the desired characteristics of the electrophotographic photoreceptor, but the ratio is based on 100 parts by weight of the binder resin. 2 to 20 parts by weight of charge generating material, especially 3 to 15 parts by weight, 40 to 200 parts by weight of a compound represented by general formula (1),
Particularly preferred is one containing 50 to 100 parts by weight. If the amount of the charge generating material and the compound represented by general formula (1) is less than the above amount, not only will the sensitivity of the photoreceptor be insufficient,
Residual potential increases. Further, if the amount exceeds the above range, the abrasion resistance of the photoreceptor will not be sufficient.

The single-layer type photosensitive layer may have an appropriate thickness, but 1
Preference is given to those having a thickness of 0 to 50 μm, especially 15 to 25 μm.

Further, the charge generation layer in the laminated photosensitive layer may be formed of a vapor deposited film, a sputtered film, etc. made of the charge generation material, and when the charge generation layer is formed together with a binder resin, the charge generation layer The ratio of the charge generating material to the binder resin can be set as appropriate, but it is preferably 5 to 5,000 parts by weight, particularly 10 to 2,500 parts by weight of the charge generating material per 100 parts by weight of the binder resin.

If the amount of the charge generating material is less than 5 parts by weight, the charge generating ability will be low, and if it exceeds 5,000 parts by weight, there will be problems such as poor adhesion. The charge generation layer may have an appropriate thickness, but may have a thickness of 0.01 to 30 μm, particularly 0.1 to 20 μm.
It is preferable to have a certain thickness.

Furthermore, the ratio of the compound represented by general formula (1) and the binder resin in the charge transport layer can be set as appropriate;
Preferably, the amount of the compound represented by formula (1) is 10 to 500 parts by weight, particularly 25 to 200 parts by weight, per 100 parts by weight of the binder resin. - If the amount of the compound represented by general formula (1) is less than 10 parts by weight, the charge transport ability will not be sufficient, and if it exceeds 500 parts by weight, the mechanical strength etc. of the charge transport layer will decrease. The charge transport layer may have an appropriate thickness, but preferably has a thickness of about 2 to 100 μm, particularly about 5 to 30 μm.

Further, the charge generation layer may contain a charge transport material together with the charge generation material, and in this case, the ratio of the charge generation material, the charge transport material, and the binder resin in the charge generation layer is set as appropriate. It is preferable that the charge generating material, the charge transporting material, and the binder resin are comprised in the same proportions as in the single-layer type photosensitive layer. Further, the charge generation layer having the above-mentioned ratio is formed to have an appropriate thickness, but is usually 0.000.
It is formed to have a thickness of about 1 to 50 μm.

The single-layer type photosensitive layer is prepared by preparing a photosensitive layer dispersion containing a charge generating material, a compound represented by the general formula [1), a binder resin, etc., and coating the dispersion on the conductive base material. It can be formed by drying or curing. The laminated photosensitive layer includes a charge generation layer dispersion containing a charge generation material and a binder resin, and a charge transport layer dispersion containing a compound represented by the general formula (1) and a binder resin. It can be formed by preparing respective coating liquids, sequentially applying them to a conductive substrate, and drying or curing them.

Further, when preparing the above-mentioned dispersion liquid, etc., various organic solvents can be used depending on the type of binder resin etc. used. The above-mentioned solvents include aliphatic hydrocarbons such as n-hexane, octane, and cyclohexane, aromatic hydrocarbons such as benzene, toluene, and xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, carbon tetrachloride, and chlorobenzene, and dimethyl ether. , ethers such as diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone, cyclohexanone, esters such as ethyl acetate, methyl acetate, dimethyl formamide, dimethyl sulfoxide, etc. The following solvents are exemplified and may be used alone or in combination of two or more. In addition, when preparing the above-mentioned dispersion liquid, etc., a surfactant, a leveling agent, etc. may be used in combination in order to improve dispersibility, coating properties, etc.

In addition, the above-mentioned dispersion liquid can be prepared using conventional methods such as mixer, ball mill, paint shaker, sand mill, etc.
It can be prepared using an attritor, an ultrasonic disperser, etc., and the obtained dispersion etc. is applied to the conductive substrate,
The electrophotographic photoreceptor of the present invention can be obtained by heating to remove the solvent.

Incidentally, in order to improve the adhesion between the conductive base material and the photosensitive layer, an undercoat layer may be formed between the conductive base material and the photosensitive layer. The undercoat layer is formed by applying a solution containing a natural or synthetic polymer so that the film thickness after drying is approximately 0.01 to 1 μm.

Further, in order to improve the adhesion between the conductive base material and the photosensitive layer, the conductive base material may be treated with a surface treatment agent such as a silane coupling agent or a titanium coupling agent. Furthermore, in order to protect the photosensitive layer, a surface protective layer may be formed on the photosensitive layer. The surface protective layer is usually made of the various binder resins or a mixed solution of the binder resin and additives such as anti-deterioration agents to a film thickness of 0.1 to 10 μm after drying, preferably 0.
．． It is formed by applying about 2 to 5 coats.

In the electrophotographic photoreceptor of the present invention, the photosensitive layer has the general formula (
Since it contains the compound represented by 1), it has excellent photostability, high sensitivity and surface potential, and low residual potential. Therefore, the electrophotographic photoreceptor of the present invention is
It is useful as a photoreceptor used in copying machines, laser beam printers, etc.

<Examples> The present invention will be described in more detail below based on Examples.

N,N'-dimethylperylene- as a charge generating material
3,4,9,10-tetracarboxy,'.

An electrophotographic photoreceptor having a laminated photosensitive layer and a single-layer electrophotographic photoreceptor were prepared using the compound shown in the above table as follows.

Examples 1 to 7 Photoreceptor for electrophotography having a laminated photosensitive layer 10 parts by weight of the above charge generating material, 10 parts by weight of vinyl chloride-vinyl acetate copolymer (manufactured by Tsukisui Kagaku Kogyo Co., Ltd., trade name: Meiko Sletsku C) and A charge generation layer coating solution consisting of a fixed amount of tetrahydrofuran is prepared, and the resulting coating solution is applied onto an aluminum sheet and heated at 100°C for 30 minutes to generate a charge with a film thickness of 0.5μ. formed a layer.

Next, a charge transport layer was formed using compound No. shown in the table above as a charge transport material. That is, 7 parts by weight of the compound shown in Table 1, 10 parts by weight of bisphenol Z type car recarbonate (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name PCZ), and a predetermined amount of benzene were mixed and dissolved to prepare a coating liquid for the charge transport layer. At the same time, a charge transport layer having a film thickness of 25 μm was formed by coating on the charge generation layer and heating and drying, thereby producing an electrophotographic photoreceptor having a laminated photosensitive layer.

Comparative Examples 1 to 3 In place of the charge transport materials of Examples 1 to 7, 4°4'-bis[N-phenyl-N-(3-methylphenyl)aminocodiphenyl (Comparative Example 1), 4°4' -Bis [N, N-
di(4-methylphenyl)amino]-2,2'-dimethyldiphenyl (Comparative Example 2), 4,4'-bis[N
, N-di(4-methylphenyl)amino]-3,3'
- Using dimethyldiphenyl (Comparative Example 3), an electrophotographic photoreceptor having a laminated photosensitive layer was produced in the same manner as in Examples 1 to 7 above.

Examples 8 to 14 Photoreceptor for electrophotography having a single-layer type photosensitive layer 8 parts by weight of the above charge generating material, 70 parts by weight of the compound shown in Table 2, bisphenol A type polycarbonate (manufactured by Kaneni Kasei Co., Ltd., trade name: Panlite L) A coating solution for a single layer type photosensitive layer consisting of 100 parts by weight of -12253 and a predetermined amount of tetrahydrofuran was prepared, coated on an aluminum sheet, and heated at a temperature of 100°C for 30 minutes.
By heating for 0 minutes, an electrophotographic photoreceptor having a single-layer photosensitive layer with a thickness of 25 μm was produced.

Comparative Examples 4 to 6 Comparative Example 1 was used instead of the charge transport material of Examples 8 to 14 above.
Electrophotographic photoreceptors having a single-layer type photosensitive layer were prepared in the same manner as in Examples 8 to 14 using the charge transport materials No. 3 to 3.

Then, in order to examine the charging characteristics and photosensitivity characteristics of the electrophotographic photoreceptors obtained in the above Examples and Comparative Examples, an electrostatic copying paper tester (manufactured by Kawaguchi Electric Co., Ltd., Model 5P-428) was used.
-6.0 KV for a photoreceptor with a laminated photosensitive layer, +6.0 KV for a photoreceptor with a single layer photosensitive layer. The electrophotographic photoreceptors of each of the Examples and Comparative Examples were negatively or positively charged by performing corona discharge under OKV conditions. In addition, the initial surface potential Vs, p, (V) of each photoreceptor was measured, and using a 10 lux tungsten lamp,
The surface of the photoreceptor is exposed to light, and the surface potential V s,p becomes 1/
Find the time until it becomes 2, and calculate the half-decreased exposure amount E l/2 (L
ow, ·see,) was calculated. Furthermore, after exposure,
The surface potential after 0.15 seconds has passed is the residual potential V r,p.

(■)

Tables 1 and 2 show the charging characteristics, photosensitive characteristics, etc. of each electrophotographic photoreceptor obtained in the above Examples and Comparative Examples.

(Hereinafter, blank spaces) As shown in Tables 1 and 2, it was found that the electrophotographic photoreceptors of Comparative Examples having a laminated type or single layer type photosensitive layer all had low sensitivity and high residual potential. On the other hand, all of the electrophotographic photoreceptors of Examples were found to have high sensitivity and low residual potential.

<Effects of the Invention> As described above, according to the electrophotographic photoreceptor of the present invention, since the photosensitive layer contains the compound represented by the general formula (1), the sensitivity is high and there is no residual It has the unique effect of having a low potential.

Claims (1)

[Scope of Claims] 1. A photoreceptor having a photosensitive layer formed on a conductive base material, for use in electrophotography, characterized in that the photosensitive layer contains a compound represented by the following general formula (1). Photoreceptor. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1) (In the formula, R^1, R^2, R^3, R^4, R^5 and R^6 are the same or different and are hydrogen atoms, It represents a lower alkyl group, a lower alkoxy group or a halogen atom. l, m, n and o represent integers of 1 to 5, p and q
At least one of these represents an integer of 2 to 4. However, R^5 and R^6 are not hydrogen atoms at the same time. ) 2, R^1, R^2, R^3, R^4, R^5 and R
^6 is the same or different, hydrogen atom, carbon number 1-4
The electrophotographic photoreceptor according to claim 1, which is an alkyl group, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom. 3, p and q are 2, and R^5 and R^6 are substituted at the 2, 5-position and the 2', 5'-position of the biphenyl skeleton; Photographic photoreceptor. 4, p and q are 3, and R^5 and R^6 are the 2, 3, 6-positions and the 2', 3', 6'- positions of the biphenyl skeleton.
The electrophotographic photoreceptor according to claim 1, wherein the electrophotographic photoreceptor is substituted at this position. 5. Claim 1 above, wherein the photosensitive layer contains metal-free phthalocyanine or titanyl phthalocyanine.
The electrophotographic photoreceptor described in .