JPH02304573A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the electrophotographic sensitive body which has a high sensitivity and high durability and is less degraded in photosensitivity in spite of repetitive use by incorporating a specific trisquisazo compd. as a charge generating compd. into the photosensitive body. CONSTITUTION:The trisaquisazo compd. expressed by formula I is incorporated as the charge carrier generating compd. into the photosensitive body. In the formula I, L denotes -O-, -S-, -SO2. The arylene group, bivalent condensed polycyclic arom. or bivalent arom. heterocyclic group may be further substd. with a substituent. A1, A2 denote an alkylene group which may have a substituent. Cp denotes a residual coupler group. The photosensitive body which has the high sensitivity and is less changed in electrophotographic characteristics after the repetitive use is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor characterized by comprising an electrophotographic photoreceptor containing a novel tetrakisazo compound.

[Conventional technology]

Conventionally, inorganic substances such as selenium, cadmium sulfide, zinc oxide, and amorphous citalin are well known as photoconductive compositions used in electrophotographic photoreceptors. These inorganic materials have the advantage of having good electrophotographic properties, that is, very good photoconductivity, charge acceptance in the dark, and insulation properties, but on the other hand, they have various drawbacks. 0 For example, selenium photoreceptors have drawbacks such as high manufacturing costs, lack of flexibility, and are susceptible to heat and mechanical shock, while cadmium sulfide photoreceptors use a toxic substance called cadmium as a material and cause pollution. I have a sexual problem. Zinc oxide has a drawback in image stability when used repeatedly over a long period of time.

Furthermore, amorphous silicon photoreceptors have drawbacks such as extremely high manufacturing costs and the need for special surface treatment to prevent deterioration of the photoreceptor surface.

In recent years, electrophotographic photoreceptors using various organic materials have been proposed in order to eliminate the drawbacks of these inorganic materials, and some of them have been put into practical use. For example, an electrophotographic photoreceptor (US Pat. No. 3,
484, 237), aggravation of poly-N-vinylcarbazole with pyrylium salt dyes (Special Publication No. 4B-256)
58), an electrophotographic photoreceptor whose main component is a eutectic complex consisting of a dye and a resin (Japanese Patent Application Laid-open No. 10,735, 1982), and the like.

Additionally, perylene application materials (U.S. Pat. No. 3,371.884), phthalocyanine pigments (U.S. Pat. No. 3.397.08),
6, No. 4,666.802, etc.), azulenium salt pigments (JP-A-59-53850.61-212,542)
No. 4,396, etc.) Squarium base pigment (U.S. Pat. No. 4,396, etc.)
610, No. 4,644.082, etc.), polycyclic quinone pigments (JP-A-59-184,348, 62-28,7)
Recently, active research has been carried out on electrophotographic photoreceptors containing organic pigments such as No. 38) and azo pigments as shown below.
Many proposals have been made.

(Bisazo pigment) JP-A No. 47-37,543, JP-A No. 60-5゜941
No., Special Publication No. 60-45,664, Japanese Patent Publication No. 116-1983
, No. 039, JP-A No. 58-123゜541, JP-A No. 6
1-260,250, JP-A-61-228,453, JP-A-61-275゜849, JP-A-61-275
．． No. 850, JP-A-53-95033, JP-A-60-
No. 2958.

(Trisazo pigment) U.S. Patent No. 4,436,800, U.S. Patent No. 4,439.5
No. 06, JP-A-53-132,347, JP-A-55-
69,148, JP-A-57-195.767, JP-A-57-'200.045, JP-A-57-204.5
No. 56, JP-A-58-31.34Q, JP-A-58-3
1.341, JP 58-154,560, JP 58-160.358, JP 58-160,359
No., JP-A-59-127,044, JP-A-59-19
6.366, JP 59-204.046, JP 59-204,841, JP 59-218.454
No., JP-A-60-111.249, JP-A-60-11
No. 1,250, JP-A-61-11.754, JP-A-6
1-22,346, JP-A-61-35.4-1, JP-A-61-67゜865, JP-A-61-121,05
No. 9, JP-A-61-163,969, JP-A-61-1
79°746, JP-A-61-230,157, JP-A-61-251,862, JP-A-61-251. =8
No. 65, JP-A-61-269,164, JP-A-62-
21.157, JP 62-78,563, JP 62-115,452 (tetrakisazo pigment) U.S. Patent No. 4,447,513, JP 60-108
, No. 857, JP-A-60-108,858, JP-A-Sho 6
O-Ill, No. 247, JP-A-60-111,248, JP-A-60-118.843, JP-A-60-176
．． No. 046, JP-A-61-103,157, JP-A-6
1-117゜559, JP-A-61-182,051, JP-A-61-194,447, JP-A-61-196
゜253, JP-A-61-212,848, JP-A-6
1-240,246, JP-A-61-273゜548, JP-A-61-284,769, JP-A-62-18.
No. 565, JP-A-62-18,566, JP-A-62-
No. 19,875.

[Problems to be Solved by the Invention] Although these electrophotographic photoreceptors have improved the mechanical properties and flexibility of the inorganic electrophotographic photoreceptors to a certain extent,
The sensitivity was still insufficient, and the electrical characteristics sometimes changed after repeated use many times, so it did not necessarily satisfy the requirements for an electrophotographic photoreceptor.

[Purpose of the invention]

An object of the present invention is to provide a novel electrophotographic photoreceptor having high sensitivity and high durability. Another object of the invention is to provide a new electrophotographic photoreceptor that exhibits little reduction in photosensitivity even after repeated use.

[Means to solve the problem]

The present invention provides an electrophotographic photoreceptor comprising a layer containing a charge carrier transporting compound and a charge carrier generating compound on a conductive support, or a layer containing a charge carrier transporting compound and a layer containing a charge carrier generating compound. The present invention relates to an electrophotographic photoreceptor characterized by containing a novel tetrakisazo compound represented by the following general formula (1) as a charge carrier generating compound.

General formula (1) In general formula (1), L is 10-1-S-1-SO□
-, arylene group, divalent fused polycyclic aromatic group or 2
arylene group, fused polycyclic aromatic group, and heteroaromatic ring group may be further substituted with a substituent; A6, A may have an rIt substituent. Represents an alkylene group.

Cp represents a coupler residue.

-a The tetrakisazo compound represented by formula [1] will be explained in more detail.

L is -0-1-S-5-SO,- or an arylene group such as phenylene, naphthalene, anthrylene, biphenylene, terphenylene, etc., indene, fluorene, acetophthene, perylene, sulolenone, anthrone, anthraquinone, benzanthrone; , divalent groups derived from fused polycyclic aromatic rings such as isocoumarin, and lysine, quinoline, oxazole, thiazole, oxadiazole, benzoxazole, benzimidazole, benzothiazole, benzotriazole, dibenzofuran, carbazole, xanthine, etc. Examples include divalent groups derived from heteroaromatic rings.

When L has a substituent, the substituent includes an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a dialkylamino group having two alkyl groups having 1 to 18 carbon atoms, and a dialkylamino group having two alkyl groups having 1 to 18 carbon atoms. 1-18 acyl group, carbon number 1-18
Acyloxy group having 2 to 18 carbon atoms, alkoxycarbonyl group having 2 to 18 carbon atoms, aryloxycarbonyl group having 7 to 16 carbon atoms, amide group having 1 to 18 carbon atoms, aryl group having 6 to 15 carbon atoms, aryl having 6 to 15 carbon atoms Examples include an oxy group, a halogen atom, a hydroxy group, a carboxyl group, a nitro group, a cyano group, and a trifluoromethyl group.

A+, At is methylene, ethylene, propylene,
Mention may be made of alkylene groups such as butylene, bentylene, octadecylene and the like.

Cp represents a known coupler residue that reacts with a diazonium salt, and is preferably a known coupler residue of an azo compound used as a charge generating compound for an electrophotographic photoreceptor. The coupler residues shown are preferred.

RI R) X is fused with a benzene ring to which a hydroxy group and Y are bonded to form an aromatic ring such as a naphthalene ring or anthracene ring, or an indole ring, a carbazole ring, a benzocarbazole ring, a dibenzofuran ring, etc. Represents an atomic group necessary to form a heterocycle.

When X is an aromatic ring or a heterocyclic ring having a substituent, the substituent includes a halogen atom (e.g., fluorine atom, chlorine atom, bromine atom, etc.), an alkyl group having 1 to 18 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, dodecyl group, octadecyl group, isopropyl group, isobutyl group, etc.), trifluoromethyl group, nitro group, amino group, cyano group, alkoxy group having 1 to B carbon atoms (e.g. methoxy group, (ethoxy group, butoxy group, etc.), and the number of substituents and substitution positions are arbitrary.

Y is -CONRiR4, C0NHN=CRsR4, -C
OOR' or a 5-membered heterocyclic ring or a 6-membered heterocyclic ring which may have a substituent.

R' represents an alkyl group having 1 to 12 carbon atoms or an aryl group.

When R1 is an unsubstituted alkyl group, specific examples include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, isopropyl group, isobutyl group, isoamyl group, isohexyl group, neopentyl group, tert-
Examples include butyl group.

When R1 is a substituted furkyl group, the substituent includes a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, a cyano group, an amino group, an alkylamino group having 1 to 12 carbon atoms, and an alkylamino group having 1 to 12 carbon atoms.
A dialkylamino group having two alkyl groups of 12, a halogen atom, and a carbon number of 6~! There are 5 aryl groups, etc. Examples include hydroxyalkyl groups (e.g., hydroxymethyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, 2-hydroxypropyl group, etc.), alkoxyalkyl groups (e.g., methoxymethyl group, 2-methoxyethyl group, 3-methoxypropyl group, ethoxymethyl group, 2-ethoxyethyl group, etc.), cyanoalkyl group (e.g., cyanomethyl group, 2-cyanoethyl group, etc.), aminoalkyl group (e.g., aminomethyl group, 2-aminoethyl group, (3-aminopropyl group, etc.), (alkylamino)alkyl group (e.g. (methylamino)methyl group, 2
-(methylamino)ethyl group, (ethylamino)methyl group, etc.), (dialkylamino)alkyl group (e.g., (
dimethylamino)methyl group, 2-(dimethylamino)ethyl group, etc.), halogenoalkyl group (e.g., fluoromethyl group, trifluoromethyl group, chloromethyl group, etc.),
Aralkyl group (e.g. benzyl group, phenethyl group, etc.)
can be given.

When R1 is an unsubstituted aryl group, specific examples include a phenyl group, a naphthyl group, an anthryl group, and the like.

When R1 is a substituted aryl group, the di-substituents include a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, a cyano group, an amino group, an alkylamino group having 1 to 12 carbon atoms, and an alkylamino group having 1 to 12 carbon atoms.
Examples include a dialkylamino group having two 12 alkyl groups, an arylazo group having 6 to 12 carbon atoms, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a nitro group, and a trifluoromethyl group. Examples include hydroxyphenyl group, alkoxyphenyl group (e.g., methoxyphenyl group, ethoxyphenyl group, etc.), cyanophenyl group, aminophenyl group, (alkylamino)phenyl group (e.g., (methylamino)phenyl group, (ethylamine) phenyl group, etc.), (dialkylamino) phenyl group (e.g., (dimethylamino) phenyl group, (diethylamino) phenyl group, etc.), halogenophenyl group (e.g., fluorophenyl group, chlorophenyl group, bromophenyl S, etc.), Alkylphenyl groups (for example, tolyl group, ethylphenyl group, cumenyl group, xylyl group, mesityl group, etc.), nitrophenyl group, trifluoromethylphenyl group, and substituents thereof (which may be the same or different from each other) Mention may be made of phenyl groups having two or three atoms.

However, the position of the substituent is arbitrary.

R1 is a hydrogen atom, a lower alkyl group having 1 to 6 carbon atoms, a carbamoyl group, a carboxyl group, an alkoxycarbonyl group having an alkoxy group having 1 to 12 carbon atoms, or an aryloxycarbonyl group having an aryloxy group having 6 to 20 carbon atoms. and substituted or unsubstituted amino groups are preferred.

When R8 is a substituted amino group, specific examples include a methylamino group, an ethylamino group, a propylamino group, a phenylamino group, a tolylamino group, a benzylamino group, a diethylamino group, a diphenylamino group, and the like.

When R1 is a lower alkyl group, specific examples include a methyl group, an ethyl group, a propyl group, a rutile group, an isopropyl group, an isobutyl group, and the like.

When R'' is an alkoxycarbonyl group, specific examples thereof include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, an isopropoxycarbonyl group, a benzyloxycarbonyl group, and the like.

When R2 is an aryloxycarbonyl group, specific examples thereof include a phenoxycarbonyl group and a doloxycarbonyl group.

R3 is an alkyl group having 1 to 20 carbon atoms, an aromatic carbocyclic group such as a phenyl group, a naphthyl group, an aromatic heterocyclic group such as a dibenzofuranyl group, a carbazolyl group, a dibenzocarbazolyl group, or a substituted group thereof. Body is preferred.

When R3 is a substituted or unsubstituted alkyl group, specific examples thereof include the same groups as the above-mentioned examples of the substituted or unsubstituted alkyl group for R1.

When R3 is an aromatic carbocyclic group having a substituent or an aromatic heterocyclic group having a substituent, specific examples of the substituent include a hydroxy group, a cyano group, a nitro group, a halogen atom (e.g., a fluorine atom, a chlorine atom, , bromine atom, etc.), carbon number 1-1
2 alkyl groups (e.g., methyl group, ethyl group, propyl group, isopropyl group, etc.), alkoxy groups having 1 to 12 carbon atoms (e.g., methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, isopropoxy group) basis,
isobutoxy group, isoamyloxy group, tart-butoxy group, neopentyloxy group, etc.), trifluoromethyl group, trimethylsilyl group, methanesulfonyl group, amino group, alkylamino group having 1 to 12 carbon atoms (e.g.
methylamino group, ethylamino group, propylamino group, etc.), dialkylamino group having 1 to 12 carbon atoms (e.g. dimethylamino group, diethylamino group, N-methyl-N-
ethylamino group, etc.), an arylamino group having 6 to 12 carbon atoms (e.g., phenylamino group, tolylamino group, etc.),
Diarylamino group having two aryl groups having 6 to 15 carbon atoms (e.g. diphenylamino group, etc.), 6 to 15 carbon atoms
12 arylazo groups (e.g. phenylazo group, chlorophenylazo group, fluorophenylazo group, promophenylazo group, cyanophenylazo group, ethoxycarbonylphenylazo group, nitrophenylazo group, acetamidophenylazo group, methylphenylazo group, methylphenylazo group, n-octylphenylazo group, trifluoromethylphenylazo group, trimethylsilylphenylazo group, methanesulfonylphenylazo group, etc.), carboxyl group, alkoxycarbonyl group having an alkoxy group having 1 to 18 carbon atoms ( For example, methoxycarbonyl group, ethoxycarbonyl group, etc.), aryloxycarbonyl group having an aryloxy group having 6 to 16 carbon atoms (
For example, phenoxycarbonyl group, naphthoxycarbonyl group, etc.), alkali metal carboxylad group (examples of alkali metal cations, Na", K", Li, etc.), alkali metal sulfonato groups (examples of alkali metal cations, Na
", K", L t・, etc.), alkylcarbonyl group (
(e.g., acetyl group, propionyl group, benzylcarbonyl group, etc.), arylcarbonyl group having an aryl group having 6 to 12 carbon atoms (e.g., benzoyl group, toluoyl group, etc.), alkylthio group having 1 to 12 carbon atoms (e.g., methylthio group, ethylthio group, etc.), or carbon number 1 to 12
arylthio groups (e.g., phenylthio group, tolylthio group, etc.), the number of substituents is 1 to 5, and when multiple substituents are bonded, they may be the same or different from each other. The bonding position of the substituent may be arbitrary.

As R4, a hydrogen atom or the same group as the above-mentioned specific example of Rs is preferable.

When Y represents a non-disubstituted 5-membered heterocyclic ring or a 6-membered heterocyclic ring,
Specific examples include an imidazole ring, an oxazole ring, a thiazole ring, a benzimidazole ring, a benzothiazole ring, a benzoxazole ring, a pyrimidine ring, and a perimidine ring.

When Y represents a 5-membered or 6-membered heterocyclic ring having a substituent, specific examples of the substituent are the same as the above-mentioned specific examples of the substituent when Rs is an aromatic carbocyclic group having a substituent. I can give you the basics.

Although it is possible to substitute at any position from the 3rd to 8th positions of the naphthalene ring, it is preferable to substitute at the 8th position.

B represents an aromatic hydrocarbon divalent group or a heterocyclic divalent group containing a nitrogen atom in the ring, and these are all alkyl groups, halogen atoms, nitro groups, trifluoromethyl groups,
Examples of divalent groups of aromatic hydrocarbons that may be substituted with cyano groups or hydroxy groups include O-phenylene groups, O-phenylene groups, O-phenylene groups, O-phenylene groups, O-phenylene groups,
- Naphthylene group, peri-naphthylene group, 1,2-anthraquinonylene group, 9,10-phenanthrylene group, etc. Examples of heterocyclic divalent groups containing a nitrogen atom in the ring include 3,4-pyrazolesilyl group, 2.3-pyridiyl group, 4.5-pyrimidinediyl group, 6.7-indazolediyl group, .6-benzimidazolediyl group, 6°7-chiralindiyl group, etc.

Next, specific examples of the tetrakisazo compounds of the present invention will be given, but the present invention is not limited thereto. Alternatively, it represents a coupler residue shown in Table 4.

Table 2 Table 2 (continued) Table 2 (continued) Table 2 (continued) Table 2 (continued) Table 2 (continued) Table 2 (continued) Table 2 (continued) Table 2 ( Table 2 (continued) Table 4 (continued) Table 4 (continued) Table 4 (continued) Table 4 (continued) Table 4 (continued) Table 4 (continued) Table 4 (continued) Table 4 (vt) The novel tetrakisazo compound of the present invention can be easily synthesized by the following method. That is, the tetraamino compound represented by the general formula [2] is octaazotized by a conventional method and camped with the corresponding coupler in the presence of an alkali, or the octazonium salt is isolated in the form of a borofluoride salt, zinc chloride double salt, etc. After that, it can be easily synthesized by coupling with a coupler in a solvent such as N,N-dimethylformamide or dimethyl sulfoxide in the presence of an alkali.

General formula [2] However, the symbol has the same meaning as in the general formula [1] above.

-A tetraamino compound of formula (21) can be obtained by reducing the tetranitro compound [3], which can be synthesized by the synthesis route (11 or (2)) shown below, under appropriate conditions, for example, with iron powder and dilute hydrochloric acid or with stannous chloride and hydrochloric acid. It can be easily synthesized by

Synthetic route (1) Synthetic route (2) [3] However, L represents the same meaning as in the above general formula (1).

Synthesis example (compound group (5) in Table 1, coupler is (Cp) in Table 2
Synthesis of a tetrakisazo compound which is '-21)) A tetraamino compound represented by the following structural formula [4] 4.
96 g (0.01 sol) were added to dilute hydrochloric acid prepared from 25 ml of concentrated hydrochloric acid and 30 d of water and stirred for about 30 minutes on a 60° C. water bath.The mixture was then cooled to 0° C. and added with 3.0 ml of sodium nitrite. A solution of 04 g dissolved in water was added dropwise at 0° C. over about 20 minutes. Thereafter, the mixture was stirred at the same temperature for 1 hour, a small amount of unreacted material was filtered off, and the filtrate was prepared in a separate container.Coupler (Cp'-21) 15.
28g (0.04sol), sodium acetate 12.3g
was added dropwise to a solution consisting of 50 d of water and 300 ml of DMF while stirring under water cooling. After stirring at room temperature for 2 hours, the formed crystals were collected by filtration and purified by repeated washing with water and acetone. 16.56 g of a black powder bundle of tetrakisazo compound was obtained. Yield 80%, decomposition temperature 27
0℃ or higher.

Elemental analysis value Molecular weight 2070.24 as C+xsH*mN+sO++ Calculated value C74,26%, H4,28%, N12°18% Actual value C74,31%, H4,25%, NI2°06% Electrophotographic exposure of the present invention The body has an electrophotographic photosensitive layer containing one or two types of tetrakisazo compounds represented by the general formula (1). Various forms of electrophotographic photoreceptors are known, and the electrophotographic photoreceptor of the present invention may be any type of photoreceptor;
or (II[) type electrophotographic photoreceptor structure.

(1) An electrophotographic photosensitive layer in which a tetrakisazo compound is dispersed in a binder or a charge carrier transport medium is provided on a conductive support.

(■) A charge carrier generation layer containing a tetrakisazo compound as a main component is provided on a conductive support, and a charge carrier transport layer is provided thereon.

(III) A charge carrier transport layer is provided on a conductive support, and a charge carrier generation layer containing a tetrakisazo compound as a main component is provided thereon.

The tetrakisazo compound of the present invention has an action of generating charge carriers with extremely high efficiency when it absorbs light.The generated charge carriers are transported by a charge carrier transporting compound.

To produce an electrophotographic photoreceptor of type (1), fine particles of a tetrakisazo compound are dispersed in a binder solution or a solution containing a charge carrier transport compound and a binder solution, and this is coated on a conductive support. , just dry it. The thickness of the electrophotographic photosensitive layer at this time is 3 to 30 μm.
, preferably 5 to 20μ.

To prepare a photoreceptor of type (If), a charge carrier generation layer is formed by vacuum evaporation of a tetrakisazo compound on a conductive support, or fine particles of a tetrakisazo compound are deposited in a suitable solution in which a binder resin is dissolved. The dispersion obtained by dispersing in a solvent is applied and dried to form a charge carrier generation layer, and if necessary, the surface is finished by a method such as puff polishing or the film thickness is adjusted. , by applying a solution containing a charge carrier transporting substance and a binder resin thereon and drying it. The thickness of the charge carrier generation layer at this time is 0. O
1μ to 4μ, preferably 0. The thickness of the charge carrier transport layer is preferably 3μ to 30μ, preferably 5μ to 2μ.
0 μ is good.

The type (III) electrophotographic photoreceptor can be produced by reversing the stacking order of the type ('') electrophotographic photoreceptor.

Used with type photoreceptors such as N), (■) and (fil).
The tetrakisazo compound is used after being dispersed into particles of 0.1 μm to 2 μm, preferably 0.31 I to 2 tt, using a dispersing machine such as a ball mill, sand mill, or vibration mill.

If the amount of the tetrakisazo compound used in the type (f) electrophotographic photoreceptor is too small, the sensitivity will be poor, and if it is too large, the charging property will be poor, the film strength of the electrophotographic photosensitive layer will be poor, and the When a binder is used, the tightening ratio of the tetrakisazo compound in the photographic photosensitive layer is 0.01 to 2 times the weight of the binder, preferably 0.05
The ratio of the charge carrier transport compound to the binder is 0.1 to 2 times by weight, preferably 0.1 to 1 times by weight. 3-1
．． In the case of a charge carrier transport compound that can itself be used as a binder, the amount of the tetrakisazo compound to be added is 0 to 5 times the weight of the charge carrier transport compound.
．． It is preferable to use 0.01 to 0.5 times the amount by weight.

Furthermore, when forming a tetrakisazo compound-containing layer which becomes a charge carrier generating compound-containing layer in type (■) and (III) electrophotographic photoreceptors, the amount of tetrakisazo compound used is 0.1 times or more by weight relative to the binder. Preferably, if it is less than that, sufficient sensitivity cannot be obtained, and it can be used without a binder. The proportion of the charge carrier transport compound in the charge carrier transport compound-containing layer is preferably 0.2 to 2 times, preferably 0.3 to 1.5 times the weight of the binder. If a molecular charge carrier transport compound is used, no other binder can be used.

The conductive support used in the electrophotographic photoreceptor of the present invention includes a metal plate made of aluminum, copper, zinc, etc., a plastic sheet or plastic film made of polyester, aluminum, indium oxide, tin oxide, etc.
Paper that has been vapor-deposited or dispersed coated with a conductive material such as copper iodide, or that has been conductively treated with an inorganic salt such as sodium chloride or calcium chloride or an organic quaternary ammonium salt is used.

When a binder is used, it is preferable to use a film-forming polymer that is hydrophobic, has a high dielectric constant, and is electrically insulating. Examples of such a polymer include the following: These examples can be listed, but of course the examples are not limited to these examples.

Polycarbonate, polyester, polyester carbonate, polysulfone, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer Coalescence, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone
Alkyd resin, phenol-formaldehyde resin,
Styrene-alkyd resin, styrene-maleic anhydride copolymer, phenoxy resin, polyvinyl butyral resin, poly-N-vinylcarbazole.

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

In the photoreceptor of the present invention, a plasticizer can be used in combination with a resin binder.

Plasticizers include biphenyl, chlorinated biphenyl, 0-terphenyl, p-terphenyl, dibutyl phthalate, dimethyl glycol phthalate, dioctyl phthalate,
Examples include triphenyl phosphoric acid, chlorinated paraffin, dilauryl thiodipropionate, and the like.

When producing the electrophotographic photoreceptor of the present invention, additives such as a sensitizer may be used in the photosensitive layer.

Sensitizers include triallylmethane dyes such as brilliant green, Victoria blue B, methyl violet, crystal violet, and acid halo B; xanthine dyes such as rhodamine B, rhodamine 6G, rhodamine G extra, eosin S1 erythrosine, rosebencal, and fluorescein; Thiazine dyes such as methylene blue, C11, Ba5ic, Violet7 (C,1,
Anthracene dyes such as 48020), cyanine dyes, 2
．． Examples include pyrylium dyes such as 6-diphenyl-4-(N,N-dimethylaminophenyl)thiapyrylium verchlorate and benzopyrylium salt (described in Japanese Patent Publication No. 4B-25,658).

Further, in order to improve the surface properties of the electrophotographic photoreceptor, silicone oil, fluorine-based surfactant, etc. can be used.

In the present invention, charge carrier transport materials used in the charge carrier transport layer are 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.

Compounds that transport electrons include compounds having an electron-withdrawing group, such as 2,4,7-) dinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 9-dicyanomethylene-2, 4,7-dolintrofluorenone, 9-dicyanomethylene-2,4,5,7-tetranitrofluorenone, tetranitrocarbazole,
Kurorani JLt, 2. 3-dichloro-5,6-dicyanobenzoquinone, 2,4.7-dolinitro9.10-
phenanthrenequinone, tetrachlorophthalic anhydride,
Examples include terracyanolythylene and tetracyanoquinodimethane.

Compounds that transport holes include compounds having an electron-donating group, such as polymer compounds, such as (a) Japanese Patent Publication No. 34-1
Polyvinylcarbazole and its derivatives described in Japanese Patent Publication No. 0,966, (b) Japanese Patent Publication No. 43-18.674, Japanese Patent Publication No. 43-19゜1
Polyvinylpyrene, polyvinylanthracene, poly-2-vinyl-4-(4'-dimethylaminophenyl)-5-phenyloxazole, poly-3-
Vinyl polymers such as vinyl-N-ethylcarbazole; (c) Polymers such as polyacetylene, polyindene, and copolymers of acenaphthylene and styrene described in Japanese Patent Publication No. 1986-193; (d) Japanese Patent Publication No. 1984-1983 Condensation resins such as pyrene-formaldehyde resin, brompyrene-formaldehyde resin, and ethylcarbazole-formaldehyde resin described in Japanese Patent Publication No. 940, (e) Japanese Patent Publication No. 56-90,883 and Japanese Patent Publication No. 56-161.550. Among various triphenylmethane polymers or low molecular weight ones, (f) triazole derivatives described in U.S. Pat. No. 3,112,197 etc., (g) U.S. Pat.
, 189.447, (h) imidazole derivatives described in Japanese Patent Publication No. 37-16.096, etc. (1) U.S. Patent No. 3,615,402 No. 3,820
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．． No. 336, JP-A No. 54-83゜435, No. 54-1
10,836, US Pat. No. 54-119,925, publications, etc., (1) U.S. Pat.
．． No. 703, No. 3,240.597, No. 3.658.
No. 520, No. 4,232,103, No. 4,175,9
No. 61, No. 4,012゜376, West German Patent ([)A
S)L Llo.

No. 518, Special Publication No. 49-35, 702, No. 39-27
, No. 577, JP-A No. 55-144.250, No. 56-
Arylamine derivatives described in US Pat. No. 119,132, US Pat. No. 56-2.437, publications, etc.; (m) amino-substituted chalcone derivatives described in US Pat. N,N-bical basil derivatives described in U.S. Patent No. 3,542,546 etc., (o) U.S. Patent No. 3
, 257,203, etc. (p) Styryl anthracene derivatives described in JP-A-56-46-234, etc., (q) JP-A-54-110,837, etc. Fluorenone derivatives, (r) U.S. Pat.
No. 59,143 (corresponding to U.S. Patent No. 4,150°987), No. 55-52,063, No. 55-52,064
No. 55-46.760, No. 55-85,495, No. 57-11゜350, No. 57-148,749, No. 57-104.144, etc. (s) U.S. Pat. No. 4,047,948, 4. 04
No. 7.949, No. 4,265,990, No. 4.273
, No. 846, No. 4,299,897, No. 4.306,
Benzidine derivatives described in JP-A-58-190.953 and JP-A-59-95.
No. 540, No. 59-97, 148, No. 59-195,
Examples include stilbene derivatives described in JP-A No. 658 and JP-A No. 62-36,647.

In the present invention, the compound that transports charge carriers is (a
The present invention is not limited to the compounds listed in ) to (1), and all hitherto known charge carrier transport compounds can be used.

When producing the electrophotographic photoreceptor of the present invention, additives such as an aggravating agent may be added to the charge generation layer and the charge transport layer, or a charge transport compound may be added to the charge generation layer. May be used.

Exacerbators include chloranil, tetracyanoethylene,
Examples include methylbioleft, rhodamine B, cyanine dye, merocyanine dye, pyrylium dye, and thiapyrylium dye.

In addition, in the electrophotographic photoreceptor of the present invention, an adhesive layer or a barrier layer can be provided between the conductive support and the photosensitive layer, if necessary. The materials used for these layers include:
In addition to the polymers used in the resin binder, gelatin, casein, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, and JP-A-59-84
, 247, styrene-butadiene polymer latex or aluminum oxide described in JP-A-59-114,544, and the thickness of these layers is preferably lum or less.

The photoreceptor obtained as described above may be further provided with measures to prevent interference fringes that occur when coherent light such as a laser is used for exposure, if necessary. Such techniques include the installation of an undercoat layer having a light scattering and reflective surface as described in JP-A No. 60-186.850;
Installation of a titanium black-containing subbing layer as described in No. 258, a method for absorbing most of the light from the light source used in a charge carrier generation layer as described in JP-A-58-82, 249, JP-A-61-18
, 963, a method for causing a charge carrier transport layer to have a phase-separated structure, a method for incorporating a substance that absorbs or scatters coherent light into a photoconductive layer, as described in JP-A-60-86゜550; A method of providing a recessed portion having a depth of 1 part 4 or more of the wavelength of coherent light on the surface of a photoreceptor described in JP-A-63-106.757, JP-A-62-172,371, JP-A-62-
Examples include the method described in No. 174.771, in which a light scattering layer or a light absorption layer is provided on the back side of a transparent support.

The electrophotographic photoreceptor of the present invention has been described in detail above, and the electrophotographic photoreceptor of the present invention is generally characterized by high sensitivity and little change in electrophotographic characteristics upon repeated use.

The electrophotographic photoreceptor of the present invention can be widely applied to photoreceptors for printers using lasers, cathode ray tubes, LEDs, etc. as light sources in addition to electrophotographic copying machines.

The photoconductive composition containing the tetrakisazo compound of the present invention can be used as a photoconductor for the picture tube of a video camera, or for a light receiving device provided on the entire surface of a one-dimensional or two-dimensional array of semiconductor circuits for signal transfer or scanning. It can be used as a photoconductive layer of a solid-state imaging element having a layer (photoconductive layer). Also, A,
In, Ghosh.

Tom Feng, J. Appl Ph5y.

49 (12), 59B2 (1978), it can also be used as a photoconductive layer in solar cells.

The tetrakisazo compound of the present invention can also be used as photoconductive colored particles in a photoelectrophoresis system and colored particles in a dry or wet electrophotographic developer.

In addition, the tetrakisazo compound of the present invention can be
17.162, JP 55-19,063, JP 55-161,250, JP 57-147,656
As disclosed in the above publication, the above-mentioned charge carrier transporting compounds such as oxadiazole derivatives and hydrazine derivatives are dispersed in an alkali-soluble resin such as a phenol resin, and coated on a conductive support such as aluminum. After drying, image exposure, toner development, and etching with an alkaline aqueous solution yield a printing plate with high resolution, high durability, and high sensitivity, and it is also possible to create printed circuits.

Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the Examples.
In the examples, "1 part" means "C parts by weight".

Example 1 5 parts of a tetrakisazo compound synthesized in Synthesis Example, which is the compound group (5) in Table 1 and whose coupler is (Cp-21) in Table 2, and 5 parts of a polyester resin (trade name: BaiC17200, specially manufactured by Toyobo) was added to 50 parts of tetrahydrofuran,
After dispersing in a ball mill for 12 hours, the dispersion was transferred to a conductive support using a wire round iron to form an aluminum vapor deposited film on a 75 μm polyethylene terephthalate support. Product name: Metal Me 75TS (manufactured by Toshi ■)
It was coated on top and dried to obtain a charge generation layer with a thickness of about 0.5 μm.

Next, 3.6 parts of p-(diphenylamino)benzaldehyde-N'-methyl-N'-phenylhydrazone and a polycarbonate resin (Panlite-13
00, manufactured by Kijin ■) 4 parts, dichloromethane 13.3 parts and 1
A solution prepared by mixing and dissolving 26.6 parts of , 2-dichloroethane was applied using an applicator to form a charge transport layer with a thickness of 18 μm, thereby producing an electrophotographic photoreceptor having a photosensitive layer made of 2N.

The electrophotographic properties of these photoreceptors were evaluated as follows using an electrostatic copying paper tester (Kawaguchi Electric Seisakusho Model 5P-428) (measured by static method). First, the initial surface potential Vs when the photoreceptor is charged by corona discharge of 16 KV, and the surface potential when discharged in the dark for 30 seconds.
. was measured.

Next, the photoreceptor surface is exposed to light from a tungsten lamp at an illuminance of 31 ux, and the exposure amount E50 required for the surface potential to attenuate to half of the initial surface potential v0 is determined.
And the surface potential (residual potential vm) after 30 seconds of exposure was measured. Further, similar measurements were repeated 3000 times. The results are shown in Table 5.

Table 5 Examples 2 to 25 A two-layer electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that the tetrakisazo compound shown in Table 6 was used instead of the tetrakisazo compound used in Example 1. As in Example 1, 850, ■3, and ■. , V, were measured.

The results are shown in Table 6.

Example 26 5 parts of the tetrakisazo compound used in Example-1, 40 parts of the hydrazone compound used in Example 1, and a copolymer of benzyl methacrylate and methacrylic acid 9 [η) 30°C
100 parts of methyl ethyl ketone (0.12%, methacrylic acid content: 32.9%) were added to 660 parts of dichloromethane, and dispersed in a ball mill for 12 hours. This dispersion was coated on a grained aluminum plate with a thickness of 0.25 mm and dried to produce an electrophotographic printing plate material having an electrophotographic photosensitive layer with a thickness of 6 μm.

After charging the surface potential of the photosensitive layer to +500 V by corona discharge (+5 KV) on this sample in a dark place, the sample surface was exposed to tungsten light with a color temperature of 2854 at an illuminance of 2.0 Lux. As a result, the half-reduced exposure amount (E5
0) was 3,0 Iu+c·sec.

Next, this sample was charged to a surface potential of +500 in a dark place, and then brought into close contact with a transparent original with a positive image and imagewise exposed. Add this to rsoperH (manufactured by Esso Standard Co., Ltd.)
petroleum solvent) 11. 5 g of polymethyl methacrylate (toner) dispersed in fine particles and 0.0 g of soybean oil lecithin.
It was possible to obtain a clear positive toner image by immersing the toner in a liquid developer consisting of Olg.

The toner image was further fixed by heating at 100° C. for 30 seconds. This printing plate material was immersed for 1 minute in an etching solution in which 70 g of sodium metasilicate hydrate was dissolved in 140 m of glycerin, 550 m of ethylene glycol, and 150 m of ethanol, and was washed with a stream of water while lightly brushing to remove toner adhesion. A printing plate was obtained by removing the photosensitive layer in the areas not covered by the photosensitive layer.

The printing plate produced in this way was
When printed using a D-offset printing machine, 50,000 sheets of very clear prints with no background smudges could be printed.

Patent Applicant Fuji Photo Film Co., Ltd. Procedural Amendment
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Claims (1)

[Scope of Claims] An electrophotographic photoreceptor comprising a layer containing a charge transporting compound and a charge generating compound, or a layer containing a charge transporting compound and a layer containing a charge generating compound on a conductive support. , the charge generating compound is represented by the following general formula [1
] An electrophotographic photoreceptor comprising a tetrakisazo compound represented by the following. General formula [1] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ In the general formula [1], L is -O-, -S-, -SO_
2-, represents an arylene group, a divalent fused polycyclic aromatic group, or a divalent heteroaromatic group. A_1 and A_2 represent alkylene groups. Cp represents a coupler residue.