JPH01200264A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body which has high sensitivity and small residual potential and excellent durability by the characteristic of a bisazo compd. that said compd. is excellent in carrier generatability by incorporating the bisazo compd. expressed by special formula onto a photosensitive layer formed on a base of the electrophotographic sensitive body. CONSTITUTION:This electrophotographic sensitive body contains the bisazo compd. expressed by general formula I in the photosensitive layer formed on the conductive base of said body. In general formula I, R denotes a halogen atom, alkyl group, alkoxy group, nitro group, cyano group or hydroxy group. X and Y denote a hydrogen atom, substd. or unsubstd. alkyl group, substd. or unsubstd. aryl group, substd. or unsubstd. heterocyclic group; X and Y form the ring cooperatively with each other. Further, Z denotes an atom group neces sary for forming a carbocyclic arom. ring or heterocyclic arom. ring.

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.

In addition, cadmium sulfide has problems with moisture resistance and durability, and zinc oxide has problems with durability, etc.

In order to overcome these drawbacks of inorganic photoreceptors, research and development of organic photoreceptors having photosensitive layers containing various photoconductive compounds as a main component has been actively conducted in recent years. For example, Japanese Patent Publication No. 50-10496 describes a paid photoreceptor having a photosensitive layer containing poly-N-vinylcarbazole and 2,4,7-t-nitro-9-fluorenone. However, this photoreceptor is not necessarily satisfactory in sensitivity and durability. In order to improve these drawbacks, 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 functional separation type photoreceptors because each material can be selected from a wide range and a photoreceptor with 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 photoconductor of the photoconductor separation type as described above.

Examples of using a reed-free compound as a carrier-generating substance include amorphous selenium described in Japanese Patent Publication No. 43-16198, which is used in combination with a photoconductive compound. However, 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 are not necessarily satisfactory in terms of sensitivity, residual potential, or stability during repeated use, and the range of carrier transport materials that can be selected is also limited. It does not fully satisfy the requirements.

[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.
Another object of the present invention is to provide an electrophotographic photoreceptor that is highly durable and 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 the Problems] As a result of intensive 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 [I] [In the formula, R represents a halogen atom, an alkyl group, an alkoxy group, a nitro group, a cyano group, or a hydroxy group, and X and Y represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or
Represents an unsubstituted aryl group, a substituted/unsubstituted heterocyclic group, X and Y may cooperate with each other to form a ring, and X and Y may be the same or different from each other. .

Z represents an atomic group necessary to form a carbocyclic aromatic ring or a heterocyclic aromatic ring. [Specific Structure of the Invention] Examples of the halogen atom for R in -la formula [I] include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom, and among these, a chlorine atom or a bromine atom is preferred.

The alkyl group for R is preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, ethyl group, isopropyl group, (-butyl group, trifluoromethyl group, etc.).

The alkoxy group for R is preferably an alkoxy group having 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, an isopropoxy group, a t-butoxy group, a 2-chloroethoxy group, and the like.

Among R, preferred are a halogen atom, an alkyl group, and an alkoxy group.

Among the substituted and unsubstituted alkyl groups represented by X and Y, an example of the unsubstituted alkyl group is a methyl group, and an example of the substituted alkyl group is a trifluoromethyl group.

Examples of the aryl group represented by X and Y include a phenyl group and a naphthyl group.

Examples of the heterocyclic group represented by Can be mentioned.

X and Y can cooperate with each other to form a ring, and examples of such a ring include a substituted or unsubstituted quinoline ring, an indoline ring, and the like. Further, X and Y may be the same group or different groups.

Z represents an atomic group necessary to form a carbocyclic aromatic ring or a heterocyclic aromatic ring, and examples of the former formed by Z include substituted and unsubstituted benzene rings, naphthalene rings, etc. Examples of the latter formed by Z include substituted and unsubstituted dibenzothiophene rings, carbazole rings, and the like. Among these, preferred is a substituted/unsubstituted benzene ring. In the present invention,
The carbocyclic aromatic ring or heterocyclic aromatic ring formed by Z includes those having substituents, and ff1
Examples of the 1A group include a halogen atom, an amino group, an alkyl group, a hydroxy group, and the like.

Next, specific examples of the bisazo compound shown in the above-mentioned drinkable material [I] of the present invention will be described, but the bisazo compound of the present invention is not limited thereto.

R=CH3Y=H R=CI Y=H R=Br Y=H R=I Y=H l nee, nee nee.” R=F Y=CH.

R=CN　　　　　　　　　　Y=CH.

R=OHY=) R=I Y=KD R=F Y=HR=CN
Y=HR=NO2Y=HR=OHY=CH.

R=OCH, Y=H The bisazo compound represented by the above-mentioned -drinking agent [I] of the present invention can be easily synthesized by a known method.

Synthesis Example 1 (Synthesis of Exemplified Compound N 0.1) 2.7-Diami2-4-methyl-9-fluorenone 2.24Q (0,
01 mole) was dispersed in 1011 g of hydrochloric acid and 201 g of water, and heated at 5°C.
Sodium nitrite 1.40g (0,02
A solution of 5112 moles of water was added dropwise. After continuing stirring at the same temperature for another 1 hour, insoluble matter was removed by filtration.
A solution of 4.6 g of ammonium hexafluorophosphate dissolved in 501Q of water was added to the filtrate. The precipitated tetrazonium salt was collected by filtration, and N,N-dimethylformamide (DMF) 1
It was dissolved at 00 mN. A solution of 2-hydroxy-3-naphthoic acid-benzylidene aminoanilide 5.80Q (0.02 mol) dissolved in DMF 200.1 was added dropwise while maintaining the temperature at 5° C. or lower.

Subsequently, while keeping the temperature below 5°C, a solution of triethanolamine 5 (1 (0.04 mol)) in DMF 30mj2 was added dropwise, and the mixture was stirred at below 5°C for 1 hour and at room temperature for 4 hours. After the reaction, the precipitated crystals were collected by filtration. , washed with DMF, washed with water and dried to obtain 5.87 g of the desired product.

In elemental analysis, this compound was found to have an actual value (C-72,0
%, H-4, 22%, N=14.0%) is the theoretical value (C
= 72.6%, H = 4.11%, N-13.6%
), the target exemplary compound NO
It was confirmed that the temperature was 1.

Synthesis Example 2 (Synthesis of Exemplary Compound No.407) 2.7-Diami2-4-fluoro-9-fluorenone 2.28a
(0.01 mol) was dispersed in 101f of hydrochloric acid and 201f of water, and while keeping the temperature below 5°C, 1.40 mol of sodium nitrite (+(
A solution of 0.02 mol) dissolved in 51 g of water was added dropwise. After stirring for another hour at the same temperature, insoluble matter was removed by filtration, and 4.6 g of ammonium hexafluorophosphate was added to the filtrate in 50 g of water.
m! A solution dissolved in 2 was added. The precipitated tetrazonium salt was collected by filtration and washed with N.

Dissolved in N-dimethylformamide (DMF) 1001Q. 2-Hydroxy-5 while keeping the temperature below 5℃
-(benzylideneaminocarbamoylzo[a]-cacarbazolf 58g (0.02 mol) was added to DMF200
The solution dissolved in the liquid was added dropwise.

Triethanolamine 6 while continuing to maintain the temperature below 5℃! ;I (0.04 mol) as DM F 3 On
The solution was added dropwise to the mixture, and the mixture was stirred at a temperature below 5° C. for 1 hour and at the lowest temperature for 4 hours. After the reaction, the precipitated product was collected by filtration, washed with DMF,
Wash with water, dry, and remove the target6. 12g was obtained.

This compound has the actual value (C = 72.2%, H = 3,
79%, N=14.2%) is the theoretical value (C=72.
6%, H=3, 67%, N=13. 'l1%), the target exemplified compound No. It was confirmed that it was 407.

Other compounds of the present invention were also prepared in the same manner as in the synthesis example 2 above.

7-Diami2-4-substituted-9-fluorenone was used to prepare the tetrazo form, followed by methyleneaminocarbamoyl 2-hydroxy-3-(2-hydroxy-3-naphthoate).
Substituted methyleneaminocarbamoyl)-benzo[a]-
It can be produced by reacting with substituted or unsubstituted carbazole.

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. The photosensitive layer 114 has a function-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 provided, as shown in FIG. A photosensitive layer 4 having a laminated structure including a carrier transport layer 3 as a lower layer and a carrier generation layer 2 as an upper layer is provided on a support 1, and 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. It is preferable to make the layer as thin as possible within a range of thickness sufficient to generate photocarriers in order to inject them into the carrier transport layer without causing damage.

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 either layer structure, a protective layer may be provided on the photosensitive layer as shown in FIGS. 7 to 9, and a protective layer may be provided on the photosensitive layer as shown in FIGS. 4 to 6. A subbing layer (intermediate layer) having barrier function and adhesive properties may be provided between the two layers.

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 Examples include insulating resins such as composite resins and vinyl chloride-vinyl acetate-maleic anhydride copolymer resins, as well as polymeric solid semiconductors such as poly-N-vinylcarbazole.

Further, organic amines may be added to the photosensitive layer of the present invention for the purpose of improving the carrier generation ability of the carrier generation substance, and it is particularly preferable to add a secondary amine.

Such secondary amines include, for example, dimethylamine, diethylamine, di-n propylamine, 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, di-isononylamine, di-n-decylamine, di- -isodecylamine, di-n-monodecylamine, di-isomonodecylamine, di-n-dodecylamine, di-isododecylamine, etc.

The amount of organic amines to be added is preferably 1' or less, preferably 0.2 to 0.005 times 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(6-1-butyl-3-methylphenol), 4,4'-thiobis(6-t-butyl-3-
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-monobutyl-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-humanOxyphenyl)propionyloxy]-2,2,6
, 6-titramethylpiperidyl, etc.

([) group: paraphenylenediamines N-phenyl-N'-isopropyl-p-phenylenediamine, N,N'-di-5ec-butyl-p-phenylenediamine, N-phenyl-N-sec-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.

(rV) group: organic sulfur compounds dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate, etc.

Group (V): wired 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% of the carrier transport substance.
0.1 to 100 heavy machinery parts, preferably 1
~2 parts by weight, particularly preferably 5 to 25 parts by weight.

Next, as a conductive support for supporting the photosensitive layer, a metal plate made of aluminum, nickel, etc., a metal drum, or a gold R
It is possible to use foil, a plastic film coated with aluminum, tin oxide, indium oxide, etc., or a paper, plastic film coated with a conductive substance, or a drum.

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, 5yn-tetrachloroethane, cis-
Halogenated hydrocarbons such as 1,2-dichloroethylene, 1.1.2-trichloroethane, 1.1.1-trichloroethane, 1.2-dichloropropane, chloroform, bromoform, and chlorobenzene; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; ethyl acetate,
Esters such as butyl acetate, methanol, ethanol,
Alcohols and derivatives thereof such as propatool, butanol, cyclohexanol, heptatool, ethylene glycol, methyl cellosolve, ethyl cellosolve, acetic acid cellosolve, tetrahydrofuran, 1,4-dioxane,
Ethers such as furan and ralfural, acetals, amines such as pyridine, n-butylamine, diethylamine, ethylenediamine, isopropanolamine, N,
Nitrogen compounds such as amides such as N-dimethylformamide, fatty acids and phenols, and sulfur and phosphorus compounds such as carbon disulfide and triethyl phosphate are included.

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 θ~100: 1~500: 0~500
It is.

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 10μ11, 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 derivatives, imidazole derivatives, imidasilone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds,
Pyrazoline derivatives, amine derivatives, oxacilone derivatives, benzothiazole derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives,
These include poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, and the like.

The carrier transporting substance used in the present invention is preferably one that has an excellent ability to transport holes generated during light irradiation to the support side, and is suitable for combination with the bisazo compound of the present invention. Preferred substances are the following - drinking costs (A), (B) and (
, C).

General formula (A) However, Ar1, Ar2, Ar4G, tsotL
Sott represents a substituted or unsubstituted aryl group, Ar3 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.

-・Drinking fee (B) However, R1 is a substituted or unsubstituted aryl group, or a substituted group.

It is an unsubstituted hetero rA group, and R2 is a hydrogen atom, 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. 8i34642 and No. 5111-166354.

General formula (C) R8 However, R1 is Vfi-substituted, unsubstituted alkyl group or substituted,
It is an unsubstituted aryl group, and R2 is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted alkyl group.

It is an unsubstituted alkoxy group, a substituted or unsubstituted amino group, or a hydroxy group, and R3 does not represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. Synthetic methods for these compounds and their illustrations are described in detail in Japanese Patent Publication No. 148150/1982, which can be incorporated into the present invention.

Other preferable transport items of the present invention include the following:
Examples include hydrazone compounds described in JP-A No. 5252 and JP-A No. 57-1018114, respectively.

The carrier generating substance in the carrier transport layer is preferably 20 to 200 parts by weight per 100 mm of binder resin,
Particularly preferred is a portion of 30 to 150 mm.

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

Further, in the case of a monolayer functionally separated electrophotographic photoreceptor using the bisazo compound of the present invention, the ratio of binder to bisazo compound diquitria transport material of the present invention is 0 to 100:
1~! ion: O to 500 is preferred, and the thickness of the photosensitive layer j2 to be formed is preferably 5-50 μm, particularly preferably 5 to 30 μm.

According to the present invention, one or more electron-accepting substances may be contained in the rear generation layer for the purpose of improving sensitivity, reducing residual potential or fatigue during repeated use, etc. Gulp.

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, I-dinitrobenzene, 1.3.5-1-dinitrobenzene, paranitrobenzo Nitrile, picryl chloride, quinone chlorimide, chloranil, brumanil, dichlorodicyanobarabenzoquinone, anthraquinone, dinitroanthraquinone,
2,7-dini-1-rofluorenone, 2,4.7-1-linitrofluorenone, 2゜4.5.7-titranitrofluorenone, 9-fluorenylidene [dicyanomethylene malonodinitrile], polynitro-9-fluorenylidene -[dicyanomethylenemalonodinitrile], picric acid, 0-nitrobenzoic acid, p-nitrobenzoic acid, 3.5
Examples include -dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, mellitic acid, and other compounds with high electron affinity.

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 as follows: total chyrelia transport substance:electron-accepting substance=100:
0.01 to ioo, preferably 100:0.1
~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, semiconductor lasers, and the like 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 has excellent durability, with little fatigue deterioration even after repeated use.

[Example 1] Hereinafter, the present invention will be specifically explained using actual working 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 2 g of exemplified compound N011 and 2 g of polycarbonate resin “Panlite L-1250J (manufactured by Ondai Kasei Co., Ltd.) are placed thereon at 1.2 g. - dichloroethane (110 ml) 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 chitria generation layer, and on top of that, as a carrier transport substance,
A carrier transport layer was formed by applying the following structural formula (K-1) 6o to a polycarbonate resin "Panlite L-1250J100" dissolved in 80N of 1,2-dichloroethane so that the film thickness after drying was 15 μm. A photoreceptor of the present invention was prepared.

(K-1) The photoreceptor obtained as described above was subjected to the following characteristic evaluation using an EPA-8100 electrostatic paper tester manufactured by Nichidenmon Seisakusho. After being charged for 5 seconds, it was left in the dark for 5 seconds, and then the illuminance on the photoreceptor surface was set to 35
The exposure aperture (
Half exposure! Then, E1/2 was calculated. Also 3 Q fox
-Surface potential (residual potential) after exposure with an exposure amount of SQc
Vn was determined. Further, similar measurements were repeated 100 times. The results are shown in Table 1.

Comparison VA1 The following bisazo compound (G-1) was used as a carrier generating substance.
A comparative photoreceptor was prepared in the same manner as in Example 1 except that .

(G-1) Regarding this comparative photoreceptor, measurements were carried out in the same manner as in Example 1, and the results are not shown in Table 3 (exclusive).

As can be easily seen from the results shown in Table 1, the photoreceptor of the present invention is extremely superior in sensitivity, residual potential, and repeated stability compared to the comparative photoreceptor.

Examples 2 to 4 Exemplary compounds No, 6, N0 as carrier generating substances
A photoreceptor of the present invention was prepared in the same manner as in Example 1 except that 48, No. 48 and No. 96 were used respectively, and the following compounds were used as the chyrelia transport substance, and the same measurements were performed. The results were not shown.

(K-2>(K-3> (K-4) C鵞Hs From the results shown in Table 2 and above, the electrophotographic photoreceptor using the bisazo compound of the present invention as a carrier-generating substance can be produced in the same manner as in Example 1. It can be seen that the sensitivity is high, 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 exemplified compound N
20 of each of O, 33, 81, 131, 179 and 238 and polycarbonate resin [Panrai 1 to L-1
250J 2 ++ and 1,2-dichloroethane 11
01g and dispersed with a sand grinder for 8 hours. This dispersion was applied to give a dry film thickness of 0.5 μm to form a chirelia-generating layer.

Furthermore, the following structural formula (
K-5) 6g of borino J-bonate resin "Panlite 11500J (Ondai Kasei Co., Ltd. FJ) 10g and 1.2
- A solution dissolved in 80% dichloroethane was coated to give a film thickness of 15 μm after drying to form a chyrelia transport layer, thereby producing photoreceptors of the present invention.

When the same measurements as in Example 1 were carried out on this photoreceptor, the results shown in No. 3:S were obtained.

Comparative Example 2 An electrophotographic photoreceptor was prepared in the same manner as in Example 5, except that a bisazo pigment represented by the following 1°4 formula (G-2>) was used as a carrier generator. When the same measurements as in Example 1 were carried out on the body, 11 results were shown in Table 3 (J).

(G-2> As is clear from the results in Table 3 and above, the photoreceptor of the present invention is extremely superior in sensitivity, residual potential, and repetition stability compared to the comparative photoreceptor.

Examples 10-12 Lamination of aluminum foil on polyester film 1
A vinyl chloride-vinyl acetate-maleic anhydride copolymer [S-LEC MF-10J
(manufactured by Shimizu Chemical Co., Ltd.) with a thickness of 005 μm, and on top of that, 2 g of Exemplified Compound N 0.116 and 1 polycarbonate resin “Panry IL-1250J”
2 g of the mixture was added to 110 grams of Te1-Rahydrofuran, and dispersed in a ball mill for 12 hours. This dispersion was coated to a dry film thickness of 05 μm to form a carrier generation layer, and further thereon, a carrier transport substance having the following structural formula (K-6) was applied.

A solution obtained by dissolving 6 g of each of the compounds represented by (K-7>, (K-8) and 10 g of polycarbonate resin rZ-200J (Mitsubishi Gas Chemical Co., Ltd. A carrier transport layer was formed by coating to a film thickness of 15 μm, and a photoreceptor of the present invention was prepared.

(K-6> (K-7) (K-8) The same measurements as in Example 1 were performed except that a fluorescent pair was used instead of the halogen lamp in Example 1, and the results shown in Table 4 were obtained. Ta.

Table 4 Example 13 A vinyl chloride-vinyl acetate-maleic anhydride copolymer [S-LEC MF-10J (manufactured by Shimizu Chemical Co., Ltd.) with a thickness of 0.05 μm was coated on the surface of an aluminum drum with a diameter of 6 Q mm.
An intermediate layer of m is provided, and the exemplary compound N O,9,1 is provided thereon.
2g of 37 and 160 and polyester resin [Pylon 2
00J (manufactured by Toyobo Co., Ltd.) 2° and 110 mRk of 1,2-dichloroethane were mixed, and 24
The time-dispersed dispersions were applied so that the film thickness after drying was 0.6 μm to form carrier generation layers.

Furthermore, the following compound (K
-9) 30 (+ and polycarbonate resin "Kneepilon S"
-1000J (manufactured by Mitsubishi Gas Chemical Co., Ltd.) 50a and 1.
A carrier transport layer was formed by dissolving the mixture in 2-dichloroethane 4001Q and coating it to a film thickness of 18 μm after drying, thereby producing a drum-shaped photoreceptor.

(K-9) Electrophotographic copying of each photoreceptor produced in this way
When I installed it on a modified U-Bix1550MRJ (manufactured by Nika Corporation) and copied the image, the contrast was high.
A copy image that is faithful to the original and clear is obtained.

Moreover, this did not change even after repeating 10,000 times.

Comparative Example 3 The exemplified compound in Example 13 was represented by the following structural formula (G-3).
A drum-shaped comparative photoreceptor was prepared in the same manner as in Example 13, except that the azo compound represented by
When copying images were evaluated in the same manner as above, only images with a lot of fog were obtained. Also, make a copy! I! As it is returned, the contrast of the copied image decreases until it reaches 10,0
After repeating this process 00 times, almost no copy image was obtained.

(G-3) Examples 14 to 17 Lamination of aluminum foil on polyester film 1
- vinyl chloride-vinyl acetate-maleic anhydride copolymer [S-LEC MF-10J
(manufactured by Shimizu Kagaku Co., Ltd.) with a thickness of 1.05 μm, and on top of that, as a chyrelia transport substance, the following structural formula (
K-'10) and a polycarbonate resin [Panlite l-1250, 1100 dissolved in 1,2-dichloroethane 801Q] were applied to a dry film thickness of 15 μI to form a carrier transport layer. was formed.

(K-10) Furthermore, exemplified compounds No. 71, 193. 2
2g of 25°255, the above carrier transport substance 1. sg
, Polycarbonate 1~Resin [Panlite L-1250
J 2 'J was added to 1,2-dichloroethane 30112, and the resulting solution was coated using a ball mill for 24 hours to provide a carrier generation layer having a thickness of 4 μm after drying, thereby producing a photoreceptor of the present invention.

When these photoreceptors were measured in the same manner as in Example 1, the results shown in Table 5 were 1q.

As is clear from the results shown in Table 5, the photoreceptor of the present invention is excellent in sensitivity, residual potential, and repeatability.

Example 18 Exemplary compound No. 0.30 (2 g of +) and polycarbonate resin Panrai 1-L-12501 (manufactured by Yondai Kasei Co., Ltd.) 2 g
was added to 110 d of 1,2-dichloroethane and dispersed in a ball mill for 12 hours. This dispersion was applied onto a polynisdel film coated with aluminum to a dry film thickness of 1 μm.
A layer of carrier generation layer 6, and a carrier transport layer formed on top of the carrier generation layer with the following structural formula (K-11
) 6o with polycarbonate resin [Panrai 1-L-12
50] 10 g and 110 d of 1,2-dichloroethane
A carrier transport layer was formed by applying a solution dissolved in water so that the WA thickness after drying was 15 μm, thereby forming an electrophotographic photoreceptor of the present invention.

(K-11) This photoreceptor was measured in the same manner as in Example 1, and the results shown in Table 6 were obtained.

Comparative Example 4 The following bisazo compound (G-4) was used as a carrier generating substance.
A comparative photoreceptor was prepared in the same manner as in Example 18 except that .

(G-4> This comparative photoreceptor was measured in the same manner as the actual m1M1, and the results shown in Table 6 were obtained.

Table 6 Examples 19-21 Exemplary compound No. 271 as a carrier generating substance.

342 and 457, and compounds with the following structural formulas were used as carrier transport substances, and the rest was as in Example 1.
A photoreceptor of the present invention was prepared in the same manner as in Example 8, and the same measurements were performed, and the results shown in Table 7 were obtained.

(K-12) (K-13) (K-14) Table 7, Example 22 Diameter 1001! l! An intermediate layer with a thickness of 1.05 μm made of vinyl chloride-vinyl acetate-maleic anhydride copolymer [varnish coating MF-10] (manufactured by Shimizu Chemical Co., Ltd.) was provided on the surface of the aluminum drum No. 1, and on top 4g of Exemplified Compound No. 395 was added to 1,2-dichloroethane 4001
1j2 and dispersed for 24 hours using a ball mill dispersion machine, the dispersion was applied to a dry film thickness of 0.6 μm to form a carrier generation layer.

Furthermore, the structural formula (K-9) 30o already described above and the polycarbonate resin [Nipiron S-1000] (
50 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was dissolved in 1,2-dichloroethane 400 and coated to form a carrier transport layer such that the film thickness after drying was 13 μm, and a drum-shaped photoreceptor was formed. .

The photoreceptor created in this way can be printed on an electrophotographic printer [
LP-3010] (manufactured by Konica) When installed on a modified model, a copy image with high contrast, faithful to the original, and clear was obtained. Moreover, this did not change even after repeating 10,000 times.

Comparative Example 5 A drum-shaped comparative photoreceptor was prepared in the same manner as in Example 22, except that the carrier-generating substance in Example 22 was replaced with a bisazo compound (G-5) represented by the following structural formula. When the copied image was evaluated in the same manner as in Example 22, only images with a lot of fog were obtained.Furthermore, as the copying was repeated, the last of the copied image decreased to 1, and the image was repeated 2000 times. And the copy image is 1r1
-I missed it.

(G-5> It is clear from the results of the above Examples and Comparative Examples that the photoreceptor of the present invention has better stability, sensitivity, durability, and a wide range of Girria transport substances than the comparative photoreceptor. It has remarkable characteristics such as ability to cooperate.

[Brief explanation of the drawing]

1 to 9 are cross-sectional views without showing the layer structure of the photoreceptor of the present invention, and 1 to G in the figures represent the following, respectively.

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.・Unsubstituted alkyl group, substituted ・
It represents an unsubstituted aryl group or a substituted/unsubstituted heterocyclic group, and X and Y may work together to form a ring, and X and Y may be the same or different from each other. Z represents an atomic group necessary to form a carbocyclic aromatic ring or a heterocyclic aromatic ring. ] (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), wherein 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.