JPH01200361A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve stability by forming a photosensitive layer contg. a specified bisazo compd. on an electrically conductive support. CONSTITUTION:A photosensitive layer contg. a bisazo compd. represented by formula I is formed on an electrically conductive support. In formula I, each of R1 and R2 is H, halogen, alkyl, alkoxy, nitro, cyano or hydroxy, R1's and R2's may be different from each other, respectively, Z is a group of atoms required to form a carbocyclic arom. ring or a heterocyclic arom. ring, X is a group of atoms required to form a heterocyclic arom. ring together with a benzene ring adjacent to X, and each of (m) and (n) is an integer of 1-3. The stability of the resulting sensitive body at the time of repeated use is improved.

Description

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

[Prior Art] Conventionally, inorganic photoreceptors having a photosensitive layer containing an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide, or silicon as a main component have been widely used as electrophotographic photoreceptors. However, these are not necessarily satisfactory in terms of sensitivity, thermal stability, moisture resistance, durability, etc. for example,
When selenium crystallizes, its properties as a photoreceptor deteriorate, making it difficult to manufacture.Also, selenium crystallizes due to heat, fingerprints, etc., and its performance as a photoreceptor deteriorates.

Furthermore, cadmium sulfide has problems with moisture resistance and durability, while zinc oxide has problems with durability.

In order to overcome these drawbacks of inorganic photoreceptors, research and development have been actively conducted in recent years on organic photoreceptors having photosensitive layers containing various organic photoconductive compounds as main components. For example, Japanese Patent Publication No. 50-10496 describes an organic photoreceptor having a photosensitive layer containing poly-N-vinylcarbazole and 2,4,7-dolinitro-9-fluorenone. However, this photoreceptor is not necessarily satisfactory in sensitivity and durability. In order to improve these shortcomings, attempts have been made to develop organic photoreceptors with higher performance by assigning carrier generation and carrier transport capabilities to different materials. Many studies have been conducted on such so-called function-separated type photoreceptors because each material can be selected from a wide range and a photoreceptor having arbitrary performance can be produced relatively easily.

[Problems to be Solved by the Invention] Many compounds have been proposed as carrier-generating substances in the functionally separated type photoreceptor as described above.

An example of using an inorganic compound as a carrier generating substance is, for example, amorphous selenium described in Japanese Patent Publication No. 43-16198, which is used in combination with an organic photoconductive compound. The disadvantage that the carrier generation layer crystallizes due to heat and deteriorates the characteristics as a photoreceptor has not been improved.

Furthermore, many electrophotographic photoreceptors using organic dyes or organic pigments as carrier-generating substances have been proposed. For example, as electrophotographic photoreceptors containing a bisazo compound in the photosensitive layer, JP-A-54-22834, JP-A-55-73057, JP-A-55-117151, and JP-A-56-46237 are already known. However, these bisazo compounds do not necessarily satisfy the characteristics of sensitivity, residual potential, or stability during repeated use, and the range of selection of carrier transport materials is also limited, which makes them difficult to meet the wide demands of electrophotographic processes. It does not fully satisfy.

[Object of the Invention] An object of the present invention is to provide an electrophotographic photoreceptor containing a specific bisazo compound having excellent carrier generation ability.

Another object of the present invention is to provide high sensitivity and low residual potential.
Furthermore, it is an object of the present invention to provide an electrophotographic photoreceptor with excellent durability whose properties do not change even after repeated use.

Still another object of the present invention is to provide an electrophotographic photoreceptor containing a bisazo compound that can effectively act as a carrier generating substance even in combination with a wide variety of carrier transporting substances.

Means for Solving Problem E] As a result of extensive research to achieve the above object, the present inventors have discovered that a specific bisazo compound can act as an excellent active ingredient for electrophotographic photoreceptors. , has completed the present invention.

That is, the above object of the present invention can be achieved by using an electrophotographic photoreceptor having a photosensitive layer containing a bisazo compound represented by the following general formula [I] on a conductive support.

General formula [Eco~Z.' [R+ and R2 each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a nitro group, a cyano group, or a doroxy group. However, R1 and R2 may be the same or different.

Z represents an atomic group necessary to form a carbocyclic aromatic ring or a carbocyclic aromatic INm, and X represents an atomic group necessary to form a cyclic aromatic ring in collaboration with an adjacent benzene ring. represents. m
and n represent an integer of 1.2 or 3, respectively. [Specific Structure of the Invention] Examples of the halogen atoms for R1 and R2 in the general formula [I] include chlorine atom, bromine atom, fluorine atom, and iodine atom, and among these, chlorine atom or bromine atom is preferred.

The alkyl group of R1 and R2 and the alkyl group having 1 to 4 carbon atoms are preferred, such as a methyl group, an ethyl group, an isopropyl group, a t-butyl group, and a trifluoromethyl group.

As the alkoxy group of R1 and R2, the number of carbon atoms is 1
-4 alkoxy groups are preferred, such as methoxy groups, ethoxy groups, isopropoxy groups, t-butoxy groups, and 2-rololytoxy groups.

Among the groups R1 and R2, preferred groups are a hydrogen atom, a halogen atom, an alkyl group, and an alkoxy group.

There is a carbocyclic aromatic ring formed by 2.

These carbocycles or heterocycles formed by 2 may have a substituent.

X jointly with the adjacent benzene ring Represents the atomic group necessary to form a cyclic aromatic ring.

In the general formula [I], m and n are 1°2 or 3
preferably at = n -1.

Both l and n may be the same integer or different integers. When l or n is 2 or more, R1 and R2
may be the same or different groups.

The bisazo compound represented by the general formula [I] of the present invention is
Specifically, the following general formula [I A I .

[IB], [IC], [Ding Di, [’IE].

[IIA], [IB], [IIC], [IIl] and [
IE].

Below are the blank general formulas (IAj General formula [IB] General 2rlc) General formula [ID1 General formula [IE] General formula [IIA] General formula [T[B] General formula [■Cl General formula 1: UD] General formula + 11EI Next, specific examples of the bisazo compound represented by the general formula [I] of the present invention will be described, but the bisazo compound of the present invention is not limited thereto.

Margin below.

The bisazo compound represented by the general formula [I] of the present invention can be easily synthesized by a known method.

Synthesis Example 1 (Synthesis of Exemplary Compound NO41 Represented by General Formula [IA]) 2.10 g of 3.6-diamitwo-9-fluorenone (0,
01 mol) was dispersed in 1011 g of hydrochloric acid, 20 ml of water, and heated at 5°C.
1.4 g of sodium nitrite (0,02
A solution of 5 moles of water was added dropwise. After continuing stirring at the same temperature for an additional hour, unnecessary materials were removed by filtration, and a solution of 4.6 g of ammonium hexafluorophosphate dissolved in 50 d of water was added to the filtrate.

The precipitated tetrazonium salt was collected by filtration and dissolved in 100 mQ of N,N-dimethylformamide (DMF).

A solution of 2-hydroxy-3-naphthoic acid-[3',4'-dicarboximido]anilide e, 3eg (0.02 mol) dissolved in 0MF200tj2 was added dropwise while maintaining the temperature at 5°C or lower.

While continuing to maintain the temperature below 5°C, add 1 (0.04 mol) to 1-liethanolamine 5 in DMF3011I2.
Add the solution dissolved in
Stir for hours. After the reaction, the precipitated crystals were collected by filtration, washed with DMF,
After washing with water and drying, the desired product 6.479 was obtained. The results of elemental analysis of this compound were as follows.

Calculated values: C=64.5%, H=3.81%, N=1
5.9% actual value: C=67.6%, 1-1=3.4
5%, N=16.1% Synthesis Example 2 (Synthesis of exemplified compound N 0.144 represented by general formula [ID]) 3.6-diamitwo-2.7-dipromo-9-fluorenone 3.68 ,01 mol) in 10 parts of hydrochloric acid and 20 parts of water.
Sodium nitrite 1.
．． A solution of 4 g (0.02 mol) dissolved in 5 vQ of water was added dropwise. After continuing stirring at the same temperature for an additional hour,
Unwanted substances were removed by filtration, and a solution of 4.6 g of ammonium hexafluorophosphate dissolved in 50 μl of water was added to the filtrate. The precipitated tetrazonium salt was collected by filtration and dissolved in N,N-dimethylformamide (DMF) 100112. 2-human Oxy-3-naphthoic acid-[3
',4'-diiminocarbonyl]anilide 6.62
A solution of 200 d of DMF (g<0.02 mol) was added dropwise.

Subsequently, while keeping the temperature below 5°C, a solution of triethanolamine 6o (0.04 mol) in DMF30tQ was added dropwise, and the mixture was stirred at below 5°C for 1 hour and at V temperature for 4 hours. After the reaction, the precipitated crystals were collected by filtration, washed with DMF, washed with water, and dried to obtain 7.06 g of the desired product. The results of elemental analysis of this compound were as follows.

Total sieve value: C = 58.1%, 1-1 = 2.47%, N
=10.6% Actual value: C=56.4%, H=2.7
2%, N-12,8% Other compounds of the present invention were prepared using 3,6-cyamitsu-substituted and unsubstituted-9-fluorenone to prepare a tetrazo compound in the same manner as in the above synthesis example, and 2-hydroxy- It can be produced by reacting with 3-naphthoic acid-[substituted diiminocarbonyl]-annealide or 2-hydroxy-3-naphthoic acid-[substituted dicarboximide goanilide, etc.

The bisazo compound of the present invention has excellent photoconductivity,
The electrophotographic photoreceptor of the present invention can be manufactured by providing a photosensitive layer in which the photoreceptor is dispersed in a binder on a conductive support. The bisazo compound of the present invention makes use of its excellent carrier generation ability, and by using it as a carrier generation substance and using a carrier transport substance that can effectively act in combination with this, the bisazo compound can be used as a so-called functionally separated photosensitive material. It can be a body. The functionally separated photoreceptor may be a mixed and dispersed type of both of the above substances, but it may be a carrier generation layer containing a carrier generation substance made of the bisazo compound of the present invention, and a carrier transport layer containing a carrier transport substance. It is more preferable to use a laminated type photoreceptor.

The electrophotographic photoreceptor of the present invention, for example, as shown in FIG. As shown in FIG. 2, a photosensitive layer 4 is provided with a functionally separated laminated structure in which a carrier generation layer 2 containing a carrier-transporting substance and a binder resin is a lower layer, and a carrier-transporting layer 3 containing a carrier-transporting substance and a binder resin is an upper layer. A photosensitive FJ4 having a laminated structure with a carrier transport layer 3 as a lower layer and a carrier generation layer 2 as an upper layer on a support 1, and a carrier generation substance and a carrier transport layer on the support 1 as shown in FIG. Examples include those provided with a single-layer photosensitive layer 4 containing a substance and a binder resin.

In the case of a photosensitive layer with a laminated structure, most of the incident light is absorbed by the charge generation layer, generating many charge generation carriers, and the generated charge carriers are deactivated by recombination or trapping. In order to inject carriers into the carrier transport layer without causing any damage, it is preferable to use one layer as much as possible within a film thickness range sufficient to generate photocarriers.

Further, the carrier transport layer is electrically connected to the carrier generation layer described above, and has the function of receiving and receiving charge carriers injected from the charge generation layer in the presence of an electric field and transporting these charge carriers to the surface. are doing.

In addition, in a functionally separated photoreceptor with a single layer structure, photocarriers are generated and transported in a single layer, and the carrier generation substance and the carrier transport substance are electrically bonded within the layer, and/or the carrier generation substance and the carrier transport substance are electrically bonded within the layer. Substances also contribute to carrier transport.

Further, the carrier generation layer may contain both the carrier generation substance and a part of the carrier transport substance.

In any of the layer configurations, a protective layer (6) may be provided on the photosensitive layer (4) as shown in FIGS. 7 to 9, and further, as shown in FIGS. A subbing layer (intermediate layer) (5) having a barrier function and adhesive properties may be provided between the support (1) and the photosensitive layer (4).

Examples of binder resins that can be used for the photosensitive layer, protective layer, and subbing layer include polystyrene, polyethylene, polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, and phenol. resin, polyester resin, alkyd resin, polycarbonate resin,
Addition polymer resins such as silicone resins and melamine resins, polyaddition resins, polycondensation resins, and copolymer resins containing two or more repeating units of these resins, such as vinyl chloride-vinyl acetate copolymers In addition to insulating resins such as polymeric resins and vinyl chloride-vinyl acetate-anofomaleic acid copolymer resins, molecular-like semiconductors such as poly-N-vinylcarbazole are exemplified.

Furthermore, organic amines can be added to the photosensitive layer of the present invention for the purpose of improving the carrier-generating function of the carrier-generating substance, and it is particularly preferable to add a secondary amine.

Examples of such secondary amines include dimethylamine, diethylamine, di-n-amylamine, di-isopropylamine, di-n-butylamine, di-isobutylamine,
Di-n amylamine, di-isoamylamine, di-n hexylamine, di-isohexylamine, di-n pentylamine, di-isopentylamine, di-n octylamine, di-isooctylamine, di-n nonylamine ,
Examples include di-isononylamine, di-n-decylamine, di-isodecylamine, di-n-monodecylamine, di-isomonodecylamine, di-n-dodecylamine, and di-isododecylamine.

The amount of the organic amines to be added is preferably 1 times or less, preferably 0.2 times to 0.005 times the amount of the carrier generating substance, based on the amount of the carrier generating substance.

Further, in the photosensitive layer of the present invention, an antioxidant can be added for the purpose of preventing ozone deterioration.

Typical examples of such antioxidants are shown below, but the invention is not limited thereto.

Group (I): Hindered phenols dibutylhydroxytoluene, 2.2'-methylenebis(6-t-butyl-4-methylphenol), 4.4
'-Butylidenebis(6-t-butyl-3-methylphenol), 4.4'-Thiobis(6-t-butyl-3-methylphenol),
-methylphenol), 2,2'-butylidene bis(6
-1-butyl-4-methylphenol), α-tocopherol, β-tocopherol, 2,2,4-trimethyl-6-hydroxy-7-t-butylchroman, pentaerythyltetrakis [3-(3,5- di-t-butyl-
4-hydroxyphenyl)propionate], 2.2'
-thiodiethylenebis[3-(3°5-di-t-butyl-4-hydroxyphenyl)propionate], 1.
6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], butylhydroxyanisole, dibutylhydroxyanisole, 1-[2-((3,5-di-tert-butyl) 4-hydroxyphenyl)propionyloxy)ethyl]-4-[3-<3.5-di-tert-butyl-4-
hydroxyphenyl)propionyloxy]-2,2,
6,6-titramethylpiveridyl, etc.

Group (n): Baraphenylenediamines N-phenyl-N'-isopropyl-〇-phenylenediamine, N,N'-di5ec-butyl-p-phenylenediamine, N-phenyl-N-8eC-butyl-p −
phenylene diamine, N.

N'-diisopropyl-p-phenylenediamine, N,
N'-dimethyl-N, N'-di-t-butyl-p-phenylenediamine, etc.

(Group I
Octyl-5-methylhydroquinone, 2-(2-octadecenyl)-5-methylhydroquinone, etc.

(TV) group: organic sulfur compounds dilauryl-3,31-thiodipropionate, distearyl-3,3'-thiodipropionate, tatetradecyl-3,3'-thiodipropionate, etc.

Group (V): Organic phosphorus compounds triphenylphosphine, tri(nonylphenyl)phosphine, tri(dinonylphenyl)phosphine, tricresylphosphine, tri(2,4-dibutylphenoxy)phosphine, etc.

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

These antioxidants may be added to any of the carrier generation layer, carrier transport layer, or protective layer, but are preferably added to the carrier transport layer.

In that case, the amount of antioxidant added is 10 parts of the carrier transport substance.
0.1 to 100 parts by weight, preferably 1 part by weight based on the 0 type can part
~50 parts by weight, particularly preferably 5 to 25 parts by weight.

Next, the conductive support supporting the photosensitive layer is a metal plate made of aluminum, nickel, etc., a metal drum or metal foil, a plastic film deposited with aluminum, tin oxide, indium oxide, etc., or paper coated with a conductive substance. , a film or drum of plastic or the like can be used.

In the present invention, the carrier generation layer is typically formed by applying a dispersion of the bisazo compound of the present invention described above in a suitable dispersion medium or solvent alone or together with a suitable binder resin, for example, by dip coating, spray coating, blade coating, etc. It can be provided by a method of coating on the support or subbing layer or carrier transport layer by roll coating or the like and drying it.

The bisazo compound of the present invention is made into fine particles of an appropriate particle size using, for example, a ball mill or a sand mill.
It can be dispersed in a dispersion medium.

A ball mill, homomixer, sand mill, ultrasonic disperser, attritor, etc. are used for dispersing the bisazo compound of the present invention.

Examples of the dispersion medium for the bisazo compound of the present invention include hydrocarbons such as hexane, benzene, toluene, and xylene;
Methylene chloride, methylene bromide, 1,2-dichloroethane, S'/l-tetrachloroethane, cis
- Halogenated hydrocarbons such as 1,2-dichloroethylene, 1,1.2-trichloroethane, 1,1.1-trichloroethane, 1,2-cyclobutane, chloroform, bromoform, chlorobenzene, acetone, methyl ethyl ketone, cyclohexanone, etc. Ketones, esters such as ethyl acetate and butyl acetate, methanol, ethanol, propatool, butanol, cyclohexanol, heptatool, ethylene glycol, methyl cellosolve,
Alcohols and their derivatives such as ethyl cellosolve and acetic acid cellosolve, ethers and acetals such as tetrahydrofuran, 1,4-dioxane, furan, and ralfural,
Armines such as pyridine, n-butylamine, diethylamine, ethylenediamine, isopropanolamine,
In addition to nitrogen compounds such as amides such as N,N-dimethylformamide, one or more of fatty acids, phenols, sulfur and phosphorus compounds such as carbon disulfide and triethyl phosphate, etc. can be used.

When the photoreceptor of the present invention has a laminated structure, the weight ratio of binder: carrier generating substance: carrier transporting substance in the carrier generating layer is 0 to 100: 1 to 500: 0 to 50.
It is 0.

If the content of the carrier-generating substance is less than this, the photosensitivity will be low (and the residual potential will increase), and if it is more than this, the dark decay and acceptance potential will decrease.

The thickness of the carrier generation layer formed as described above is
Preferably 0.01 to 10 μm, particularly preferably 0.1
~5 μm.

Further, the carrier transport layer can be formed by coating and drying a carrier transport substance dissolved or dispersed in an appropriate solvent or dispersion medium alone or together with the above-mentioned binder resin. As the dispersion medium used, the dispersion medium used in dispersing the carrier-generating substance can be used.

Carrier transport substances that can be used in the present invention include:
Although not particularly limited, examples include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole 134 forms, imidazole H13 forms, imidasilone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, Amine derivatives, oxacilone derivatives, 11 benzothiazoles, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene etc.

As the Ki/ria transport substance used in the present invention, one is preferably used that not only has an excellent ability to transport holes generated during light irradiation to the support side, but also is suitable for combination with the bisazo compound of the present invention. Preferred examples of such carrier transport substances include those represented by the following general formulas (A), (B) and (C).

General formula (A) However, △"1, Ar2, Ar4 are that'e tL B
m or an unsubstituted aryl group, Ars represents a substituted or unsubstituted arylene group, and R1 represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group.

Specific examples of such compounds are described in detail on pages 3 to 4 of JP-A-58-65440 and pages 3-6 of JP-A-58-198043.

General formula (B)', N-N=C-+C1(=CH)n R+R
3 However, R1 is a substituted or unsubstituted aryl group, or a substituted group.

It is an unsubstituted heterocyclic group, and R2 is a hydrogen atom and is substituted.

It represents an unsubstituted alkyl group, a substituted or unsubstituted aryl group, and n is an integer of 0.1 or 2.
It is described in the publications No. 8-134642 and No. 58-166354.

General formula (C) However, R1 is a substituted or unsubstituted argyl group or a substituted or unsubstituted aryl group, and R2 is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted.

They are an unsubstituted alkoxy group, a substituted or unsubstituted amino group, or a hydroxy group, and R3 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. Synthesis methods for these compounds and their illustrations are described in detail in Japanese Patent Publication No. 148750/1983, which can be incorporated into the present invention.

Other preferred carrier transport materials of the present invention include:
Examples include hydrazone compounds described in JP-A-57-67940, JP-A-59-15252, and JP-A-57-101844, respectively.

The carrier transporting material in the carrier transporting layer is preferably 20 to 200 parts by weight, particularly preferably 30 to 150 parts by weight, per 100 parts by weight of the binder resin.

The thickness of the carrier transport layer to be formed is preferably 5 to 5.
0 μm1, particularly preferably 5 to 30 μm.

Further, in the case of a monolayer functionally separated type electrophotographic photoreceptor using the bisazo compound of the present invention, the ratio of the binder to the bisazo compound of the present invention:carrier transport substance is 0 to 100:
1-500: preferably 0-500, and the thickness of the photosensitive layer formed is preferably 5-50 μl, particularly preferably 5-500:
It is 30 μm.

In the present invention, the carrier generation layer may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential or fatigue during repeated use, etc.

Examples of electron-accepting substances that can be used here include succinic anhydride, maleic anhydride, dibromaleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride,
Tetrabromo phthalic anhydride, 3-nitro phthalic anhydride,
4-nitrophthalic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, 0-dinitrobenzene, m-dinitrobenzene, 1.3.5-trinitrobenzene, paranitrobenzonitrile, Vicryl chloride, quinone chlorimide,
O-ranil, brumanil, dichlorodicyanobara benzoquinone, anthraquinone, dinitroanthraquinone, 2
．． 7-sinitrofluorenone, 2.4.7-dolinitrofluorenone, 2゜4.5.7-titranitofluorenone, 9-fluorenylidene [dicyanomethylenemalonodinitrile], polynitro-9-fluorenylidene-[
dicyanomethylenemalonodinitrile], picric acid, 0
-Nitrobenzoic acid, p-nitrobenzoic acid, 3.5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3.5-dinitrosalicylic acid, phthalic acid, mellitic acid, and other compounds with high electron affinity. can be mentioned.

Further, the addition ratio of the electron-accepting substance is bisazo compound of the present invention:electron-accepting substance=100:0.01 to
200, preferably 100:0.1-100.

This electron-accepting substance may be added to the carrier transport layer. The ratio of electron-accepting substances added to this layer is the weight ratio of total carrier transport substance: electron-accepting substance = 100:
0.01-100, preferably 100:0.1-
It is 50.

In addition, the photoreceptor of the present invention may also contain, if necessary, an ultraviolet absorber, an antioxidant, etc. for the purpose of protecting the photosensitive layer, and may also contain a dye for color sensitivity correction.

The electrophotographic photoreceptor containing the bisazo compound of the present invention can be sensitive to visible light and near-infrared light, but preferably has an absorption maximum at a wavelength of about 400 to 850 μm.

Examples of light sources with such wavelengths include halogen lamps,
Fluorescent lamps, tungsten lamps, gas lasers such as argon lasers, helium-neon lasers, lasers, and semiconductor lasers are generally used.

The electrophotographic photoreceptor of the present invention has the above structure,
As is clear from the Examples described below, it has excellent charging characteristics, sensitivity characteristics, and image forming characteristics, and especially shows little fatigue deterioration even when used repeatedly, and has excellent durability.

[Examples] Hereinafter, the present invention will be specifically explained using Examples, but the embodiments of the present invention are not limited thereby.

Example 1 Vinyl chloride-vinyl acetate-
Maleic anhydride copolymer “S-LEC MF-10J (
An intermediate layer with a thickness of 0.05 μm is provided, and an exemplified compound N0 represented by the general formula [IA] is provided thereon.
2g of 11 and polycarbonate m fat [Panlite l-1
250J (manufactured by Teijin Chemicals) 2(+) was added to 110ml of 1,2-dichloroethane and dispersed in a ball mill for 12 hours.

This dispersion was applied to a dry film thickness of 0.5 μm to form a carrier generation layer, and on top of this, 6 g of the following structural formula (CT-1) and a polycarbonate resin [Pan] were applied as a carrier transport layer. A photoreceptor of the present invention was prepared by forming a carrier transport layer by applying a solution obtained by dissolving 10 (l) of Light L-1250J in 801 g of 1,2-dichloroethane so that the film thickness after drying was 15 μm.

(CT-1) Photoreceptor obtained as above! 413 Using EPA-8100 model R# electric paper test machine manufactured by Kawaro Denki Seisakusho,
The following characteristics were evaluated. After charging with V for 5 seconds to a charging voltage of -6, leave it in the dark for 5 seconds, then irradiate with halogen lamp light so that the illumination intensity on the photoreceptor surface is 35 Qux-Sec to attenuate the surface potential by half. The exposure length (half exposure ff1) El/2 required for this was determined. Also 30f
The surface potential (residual potential) VR after exposure with a lux-sec exposure group was determined. Further, similar measurements were repeated 100 times. The results are shown in Table 1.

Comparative Example 1 The following bisazo compound (CG-1
) A comparative photoreceptor was prepared in the same manner as in Example 1, except that the photoreceptor was used.

(CG-1) Regarding this comparative photoreceptor, measurements were performed in the same manner as in Example 1, and the results were not shown in Table 1.

As is clear from the results in Table 1 and above, the photoreceptor of the present invention is extremely superior in sensitivity, residual potential, and repetition stability compared to the comparative photoreceptor.

Examples 2 to 4 Exemplary compound No. 20 represented by the general formula [IC] with the carrier generating substance and L, Exemplary compound No. 28 represented by the general formula [IB], Exemplary compound No. 28 represented by the general formula [IA] Photoreceptors of the present invention were prepared in the same manner as in Example 1, using No. 53 and the following compounds as carrier transport substances, respectively, and the same measurements were performed. Table 2 shows the results. The following results were obtained.

(CT-2) (CT-3) (CT-4) From the results in Table 2 and above, it is clear that the electrophotographic photoreceptor using the bisazo compound of the present invention as the 4-Yaria-generating substance was produced in the same manner as in Example 1. It can be seen that the sensitivity is low, the residual potential is low, and the repeatability is excellent.

Examples 5 to 9 Aluminum was vapor-deposited on a polyester film, the intermediate layer used in Example 1 was provided, and the general formula [IC
] Exemplified compound No. 69, Exemplified compound No. 80 represented by general formula [IE], Exemplified compound No. 80 represented by general formula [IA], Exemplified compound No. 101 represented by general formula [IA], Exemplified compound N represented by general formula [IC] 0.126, 2 g each of exemplified compound N 0.132 represented by the general formula [IC] and polycarbonate resin "Panlite 1-1250J 2 Q" were added to 110 g of 1,2-dichloroethane and dispersed with a sand grinder for 8 hours.

This dispersion liquid was applied so that the film thickness when dried was 0.5 μm to form each carrier generation layer. Furthermore, on top of that, the following structural formula (CT-5) 6a is added as a carrier transport layer.
Polycarbonate resin [1300J for Panlite]
(mjinkaseisha14) ioo and i.

A carrier transport layer was formed by applying a solution dissolved in 80 vQ of 2-dichloroethane so that the film thickness after drying was 15 μm, and photoreceptors of the present invention were prepared.

(CT-5) The same measurements as in Example 1 were performed on these photoreceptors, and the results are shown in Table 3.

Comparative Example 2 An electrophotographic photoreceptor was produced in the same manner as Examples 5 to 9, except that a bisazo compound represented by the following structural formula (CG-2) was used as a carrier generating substance.

The same measurements as in Example 1 were performed on this comparative photoreceptor, and the results are shown in Table 3.

(CG-2) Table 3 Examples 10 to 12 Vinyl chloride-vinyl acetate-
71 twin acid anhydride copolymer “S-LEC MF-10J
(manufactured by Block Chemical Co., Ltd.) with a thickness of 0.05 μm, and in the -L layer, 2 g of exemplified compound N0.158 having the structure of general formula [IB] and polycarbonate resin [
Panlite L-1250J 21) and Terra Il:
F lower 5:/110 iN was added and dispersed in a ball mill for 12 hours. This dispersion was applied to a dry film thickness of 0.5 μm to form a chyrelia generation layer, and furthermore, a carrier transport layer was formed using the following structural formulas (CT-6) and (CT-7).
), (CT-8) and 10 g of polycarbonate resin rZ-200J (manufactured by Mitsubishi Gas Kaisha, Ltd.) dissolved in 1,2-dichloroethane 801Q, the film thickness after drying was 15 μm. A carrier transport layer was formed by coating the photoreceptor of the present invention.

(CT-6) (CT-7) (CT-8) Measurements were carried out in the same manner as in Example 1, except that a fluorescent lamp was used instead of the halogen lamp in Example 1. The results are shown in Table 4. became.

Table 4 Example 13 The surface of an aluminum drum with a diameter of 601 IIl was coated with vinyl chloride-vinyl acetate-maleic anhydride copolymer "S-LEC MF-10J (Active Water Chemistry)" with a thickness of 0.
．． 05μ- intermediate layer is provided thereon, and exemplified compound No. 177 having the structure of general formula [IB], general formula [ID]
Exemplary compound No. which shows the structure of

196, Exemplary compound N having the structure of general formula [IE]
20 of O, 205 and polyester resin "Byron 200"
J (manufactured by Toyobo Co., Ltd.) 2Q was mixed with 100% 1,2-dichloroethane and Q, and the dispersion was dispersed for 24 hours using a ball mill dispersion machine. The dispersion was applied to a carrier so that the film thickness after drying was 0.6μI. A generation layer was formed.

Further, on top of this, 300 u of the following compound (CT-9) and 50 u of polycarbonate resin "Nipiron 3-1000J (manufactured by Mitsubishi Gas Chemical Co., Ltd.) were added to 400 u of 1,2-dichloroethane.
1Q and coated to form a carrier transport layer so as to have a film thickness of 18 μm after drying, thereby producing a photoreceptor.

(CT-9) Electrophotographic copying of the photoreceptor produced in this way
When it was installed on a modified U-Bix1550M RJ (manufactured by Konica) and an image was copied, a copy image with high contrast, faithful to the original, and clear was obtained.

Moreover, this did not change even if it was repeated io and ooo times.

Comparative Example 3 The exemplified compound in Example 13 was represented by the following structural formula (CG-3
) Example 13 except that the bisazo compound represented by
A drum-shaped comparative photoreceptor was prepared in the same manner as in Example 13, and the copied images were evaluated in the same manner as in Example 13. Only images with a lot of fog were obtained. Also, as copying is repeated, the contrast of the copied image decreases, and
After repeating this process 00 times, hardly any copied images were obtained.

(CG-3) Example 14 Exemplary compound No. 53-2 represented by general formula [IIA]
g and polycarbonate resin [Panlite L-1250J
(manufactured by Teijin Kasei) was added to 110 t12 of 1,2)-dichloroethane and dispersed in a ball mill for 12 hours. This dispersion was applied onto a polyester film on which aluminum had been vapor-deposited so that the dry film thickness would be 1 μm to form a carrier generation layer, and on top of that a carrier transport layer was formed using the following structural formula (CT-10). 6g was mixed with polycarbonate resin "Panlite L-1250J 10Q" in 1.
A carrier transport layer was formed by applying a solution dissolved in 2-dichloroethane 110d to a dry film thickness of 15 μm, thereby forming an electrophotographic photoreceptor of the present invention.

(CT-10) This photoreceptor was measured in the same manner as in Example 1, and the results shown in Table 5 were obtained.

Comparative Example 4 The following bisazo compound (CG-4
) A comparative photoreceptor was prepared in the same manner as in Example 14, except that the photoreceptor was used.

(CG-4) Regarding this comparative photoreceptor, measurements were performed in the same manner as in Example 1, and the results shown in Table 5 were obtained.

Table 5 Examples 15 to 17 Exemplary compounds N of general formula [I[B] as carrier generating substances
0.28, general formula [IIC]IC compound No.

132, general formula [■D] using exemplified compound No. 69,
A photoreceptor of the present invention was prepared in the same manner as in Example 1 except that compounds with the following structural formulas were used as carrier transport substances, and the same measurements were performed. .

(CT-11) (CT-12) (CT-13) As is clear from the results in Table 6, the electrophotographic photoreceptor containing the bisazo compound of the present invention as a carrier generating substance can generate a wide range of carriers. It is found that it can be used in combination with a transport substance and exhibits excellent electrophotographic properties.

Example 18 A layer of vinyl chloride-vinyl acetate-maleic anhydride copolymer "S-LEC MF-10J (manufactured by Katsusui Kagaku Co., Ltd.) with a thickness of 1,
An intermediate layer of 0.05 μm constant was provided, and 4 g of exemplified compound No. 80 of the general formula [IIE] was added to 4 g of 1,2-dichloroethane 4.
00 d and dispersed in a ball mill disperser for 24 hours, the dispersion coating was applied so that the film thickness after drying was 0.6 μm to form a carrier generation layer.

Furthermore, the structural formula already described (CT-9>309 and the polycarbonate resin "Nipiron S-1000J")
(30 Gas Chemical Company II) 50! II Dissolved in 1.2-dichloroethane 4001.12, and the film thickness after drying was 1.
A carrier transport layer is formed by coating to a thickness of 3 μ-.
A drum-shaped photoreceptor was created.

The photoreceptor created in this way can be printed on an electrophotographic printer.
When installed on a modified LP-3010J (manufactured by Konica), a copy image with high contrast, faithful to the original, and clear was obtained. Also, this is io, oo.

No matter how many times it was repeated, it didn't change.

Comparative Example 5 - Except that the carrier generating substance in Example 18 was replaced with a bisazo compound (CG-5) represented by the following structural formula,
A drum-shaped comparative photoreceptor was prepared in the same manner as in Example 18, and the copied images were evaluated in the same manner as in Example 18. Only images containing many capri were obtained. Furthermore, as copying was repeated, the contrast of the copied image decreased, and after 2000 repetitions, hardly any copied image could be obtained.

(CG-5) As is clear from the results of the above Examples and Comparative Examples, the photoreceptor of the present invention has better stability, sensitivity, durability, combination with a wide range of carrier transport substances, etc. than the comparative photoreceptor. It is extremely superior in terms of performance.

[Brief explanation of the drawing]

1 to 9 are sectional views showing the layer structure of the photoreceptor of the present invention, and 1 to 6 in the figures represent the following, respectively. 1... Conductive support 2... Carrier generation layer 3.
...Carrier transport layer 4...Photosensitive layer 5...Intermediate FJ
+ 6...1st layer Fig. 1 Fig. 4 Fig. 2 Fig. 5 Fig. 3 Fig. 6

Claims (3)

[Claims] (1) An electrophotographic photoreceptor comprising a photosensitive layer containing a bisazo compound represented by the following general formula [I] on a conductive support. General formula [I] ▲ Numerical formulas, chemical formulas, tables, etc. are included▼ [R_1 and R_2 each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a nitro group, a cyano group, or a hydroxy group. However, R_1 and R_2
may be the same or different, respectively. Z represents an atomic group necessary to form a carbocyclic aromatic ring or a heterocyclic aromatic ring. X is an atom necessary to form a heteroaromatic ring having ▲a mathematical formula, a chemical formula, a table, etc.▼ or ▲a ▲a mathematical formula, a chemical formula, a table, etc.▼ as part of it, together with the adjacent benzene ring. represents a group. m and n each represent an integer of 1, 2 or 3. ] (2) The photosensitive layer contains a carrier-generating substance and a carrier-transporting substance, and the carrier-generating substance has the general formula [
The electrophotographic photoreceptor according to claim (1), which is a bisazo compound represented by I]. (3) Claim (1) or (2) characterized in that the photosensitive layer is constituted by a laminate of a carrier generation layer containing a carrier generation substance and a carrier transport layer containing a carrier transport substance. The electrophotographic photoreceptor described above.