JPH01147550A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain superior carrier generating performance by forming on a conductive substrate a photosensitive layer containing a specified bisazo compound. CONSTITUTION:The photosensitive layer formed on the conductive substrate contains at least one of the bisazo compounds represented by formula I in which X is H, cyano, or halogen; R1 is H, halogen, alkyl, alkoxy, trifluoroalkyl, or cyano; R2 is H, halogen, alkyl, or alkoxy; Z is an atomic group necessary to form an aromatic hydrocarbon ring or hetero ring; and Y is a group of formula II, thus permitting the obtained photosensitive body to be high in sensitivity and durability and small in residual potential.

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 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. 5G-10496 describes an organic photoreceptor having a photosensitive layer containing poly-N-vinylcarbazoletro-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 the carrier generation function and the carrier transport function to different substances. 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] The first object of the present invention is to provide an electrophotographic photoreceptor containing a specific bisazo compound having excellent carrier generation ability.

A second object of the present invention is to provide an electrophotographic photoreceptor that is highly sensitive, has a low residual potential, is highly durable, and does not change its characteristics even after repeated use. .

A third 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.

Other objects of the invention will become apparent from the description of the specification circular.

[Means for Solving the Problems] As a result of intensive research to achieve the above object, the present inventors have found that a bisazo compound represented by the following general formula [I] has excellent effectiveness in electrophotographic photoreceptors. The present invention was completed by discovering that it can function as a component.

General formula [I] °・,Z,' In the formula, In the formula, R2 represents a hydrogen atom, a hydrogen atom, an alkyl group or an alkoxy group.

Z represents an atomic group necessary to constitute a carbocyclic aromatic ring or a heterocyclic aromatic ring.

In the general formula [I], X represents a hydrogen atom, a cyan group, or a halogen atom (for example, a chlorine atom), and a cyano group is particularly preferred.

The alkyl group represented by R1 is, for example, a methyl group, ethyl group, propyl group, etc., the alkoxy group is, for example, a methoxy group, an ethoxy group, etc., the trifluoroalkyl group is, for example, a trifluoromethyl group, and the halogen atom is For example, it is a chlorine atom.

Specific examples of the halogen atom, alkyl group, or alkoxy group represented by R2 are the same as those for R1.

The alkyl group or alkoxy group represented by R1 and R2 may have a substituent.

2, and these aromatic rings formed by Z may have a substituent.

The bonding position of the group represented by Y to the benzene ring is not particularly limited.

Specific examples of the bisazo compound represented by the general formula [I] (hereinafter referred to as the bisazo compound of the present invention) include:
For example, compounds having the following structural formula may be mentioned, but the bisazo compounds of the present invention are not limited thereto.

General formula (Im) General formula (Ib) -Shell formula (Ie) General formula (Id) The above bisazo compounds can be easily synthesized by known methods.

Synthesis Example (Synthesis of Exemplified Compound N018) 2.499 (0.01 mol) of 4'-diamino-2-methyl-β-cyanostilbene was dissolved in 10 mj2 of hydrochloric acid and 2 ml of water.
0112, and a solution of 1.40 (1 (0,02-El) sodium nitrite dissolved in 51Q of water was added dropwise while keeping the temperature below 5°C. After continuing stirring at the same temperature for an additional hour, Insoluble materials were removed by filtration, and a solution of 4.9 liters of ammonium hexafluorophosphate dissolved in 50,112 liters of water was added to the filtrate. It was dissolved in .12.

A solution prepared by dissolving DMF 400i12 was added dropwise while keeping the temperature below 5°C.

Subsequently, while maintaining the temperature below 5°C, a solution of 51 J (0.04 mol) of triethanolamine in 30 mN of DMF 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 6.3 g of the desired product.

The bisazo compound of the present invention has excellent photoconductivity, and when an electrophotographic photoreceptor is manufactured using the same, a photosensitive layer in which the bisazo compound of the present invention is dispersed in a binder is provided on a conductive support. However, among the photoconductivity of the bisazo compound of the present invention, it is used as a carrier-generating substance by taking advantage of its particularly excellent carrier-generating ability, and together with a carrier-transporting substance that can effectively act in combination with this. By using this, particularly excellent results can be obtained when a so-called functionally separated photoreceptor is constructed.

The functionally separated type photoreceptor may be a mixed and dispersed type of both of the above substances, but it may be a laminated type photoreceptor in which a carrier generation layer containing a carrier generation substance and a carrier transport layer containing a carrier transport substance are laminated. is more preferable.

When the bisazo compound of the present invention is used as a carrier-generating substance, there are no particular restrictions on the carrier-transporting substance used in combination with it, but examples include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazoone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, amine derivatives, oxazolone derivatives, benzothiazole derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, These include phenazine derivatives, aminostilbene derivatives, 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 by light irradiation to the support side, and is suitable for combination with the bisazo compound of the present invention. Preferred substances are the following general formulas (A), (B) and (
Examples include those represented by C).

General formula (A> However, A' 1 , Ar 2 and Ar 4 each represent a substituted or unsubstituted aryl group, Ar3 represents a substituted or unsubstituted arylene group, and R1 represents a hydrogen atom, a substituted or unsubstituted aryl group, and R1 represents a hydrogen atom, a substituted or unsubstituted arylene group, Represents an alkyl group or a substituted or unsubstituted aryl group.

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

General formula (B) However, R1 is a substituted or unsubstituted aryl group, or a substituted.

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 in detail, it is described in JP-A-58-134642 and JP-A-58-134642.
It is described in the publication No. 166354.

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

unsubstituted amiLL hydroxy group, R3 is □substituted,
Represents an unsubstituted aryl group, substituted or unsubstituted heterocyclic group. Synthesis methods and examples of these compounds are given in Japanese Patent Publication No. 57-
It is described in detail in Japanese Patent No. 148750, and 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.

Various configurations of electrophotographic photoreceptors are known, but
The electrophotographic photoreceptor of the present invention can take any of these forms.

Usually, the configuration is as shown in FIGS. 1 to 6. Figures 1 and 2
In the figure, a photosensitive IJ 4 is provided on a conductive support 1, which is a laminate of a carrier generation layer 2 containing the above-mentioned bisazo compound as a main component and a carrier transport layer 3 containing a carrier transport substance as a main component.

As shown in FIGS. 3 and 4, this photosensitive layer 4 may be provided via an intermediate 1Ii5 provided on a conductive support.

When the photosensitive layer 4 has a two-layer structure in this manner, a photoreceptor having the most excellent electrophotographic properties can be obtained. Further, in the present invention, as shown in the fifth factor and FIG. It may be provided directly or via the intermediate layer 5. Further, in the present invention, a protective layer may be provided as the outermost layer.

The carrier generation layer 2 constituting the two-layered photosensitive layer 4 is formed directly on the conductive support 1 or the carrier transport m3, or on an intermediate layer 5 such as an adhesive layer or barrier layer as required. For example, it can be formed by the following method.

M-1) A method of applying a solution in which a bisazo compound is dissolved in a suitable solvent, or a solution in which a binder resin is mixed and dissolved, if necessary.

M-2) A bisazo compound is made into fine particles (preferably particle size of 5 μm or less, more preferably 1 μm or less) in a dispersion medium using a ball mill, homomixer, etc., and a binder resin is added as necessary to mix and disperse the resulting dispersion, and the mixture is applied. how to.

Solvents or dispersion media used to form the carrier generation layer include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N,N-dimethylformamide, acetone, methylethylketone, cyclohexanone, and benzene. , toluene, xylene, chloroform, 1.2-dichloroethane, 1.2-dichloropropane, 1.1.2-trichloroethane, 1,1.1-trichloroethane, trichloroethylene, tetrachloroethane, dichloromethane, tetrahydrofuran, dioxane,
Examples include methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cellosolve, and the like.

Further, the carrier transport layer can be formed in the same manner as the carrier generation layer described above.

Any binder resin can be used to form the carrier generation layer or the carrier transport layer, but it is preferable to use a film-forming polymer that is hydrophobic, has a high dielectric constant, and is electrically insulating. preferable. Examples of such molecular polymers include, but are not limited to, the following:

P-1) Polycarbonate P-2) Polyester P-3) Methacrylic acid P-4) Acrylic resin P-5) Polyvinyl chloride P-6) Polyvinylidene chloride P-7) Polystyrene P-8) Polyvinyl acetate P-9 ) Styrene-butadiene copolymer P-10) Vinylidene chloride-acrylonitrile copolymer p-11) Vinyl chloride-vinyl acetate copolymer P-12>
Vinyl chloride-vinyl acetate-maleic anhydride copolymer p-13) Silicone resin p-14) Silicone-alkyd resin p-15) Phenol formaldehyde resin p-16) Styrene-
Alkyd resin p-17) Poly-N-vinylcarbazole p-18) Polyvinyl butyral p-19) Polyvinyl formal These binder resins can be used alone or as a mixture of two or more.

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 preferably 0 to 100:1 to 500:O to
It is 500.

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.

In addition, the carrier transport substance is 20 to 200 ffl ffi per 100 parts by weight of the binder' resin in the carrier transport layer.
parts by weight, particularly preferably from 30 to 150 parts by weight.

The thickness of the carrier generation layer formed as described above is
Preferably 0.01 to 10 μm1, particularly preferably 0.1
~5μl.

Further, the thickness of the carrier transport layer to be formed is preferably 5 to 50 Ltm, particularly preferably 5 to 30 μm.

On the other hand, when the photoreceptor of the present invention has a single-layer functionally separated structure, the weight ratio of binder: carrier generating substance: carrier transporting substance in the photosensitive layer is 0 to 100: 1 to 500: 1 to 50.
0 is preferable, and the thickness of the photosensitive layer to be formed is 5 to 50 μm.
is preferable, particularly preferably 5 to 30 μm.

The conductive materials used in the electrophotographic photoreceptor of the present invention include metal plates including alloys, metal drums or conductive polymers, aluminum including conductive compounds and alloys such as indium oxide, palladium, gold, etc. Apply a thin metal layer of
Examples include paper and plastic films made conductive by vapor deposition or lamination. As an intermediate layer such as an adhesive layer or a barrier layer, in addition to the high molecular weight polymer used as the binder resin, polyvinyl alcohol, ethyl cellulose, and the like can be used.

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.

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, and the like.

The amount of 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.

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

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

Group (I): sender biphenols dibutylhydroxytoluene, 2,2'-methylenebis(6-t-butyl-4-methylphenol), 4.4
'-Butylidenebis(6-[-butyl-3-methylphenol), 4.4'-Thiobis(6-t-butyl-3
-methylphenol), 2,2'-butylidene bis(6
-t-butyl-4-methylphenol), α-tocoff I
role, β-tocopherol, 2.2.4-trimethyl-6-hydroxy-7-t-butylchroman, pentaerythyltetrakis [3-(3.5-di-butyl-4-hydroxyphenyl)propionate], 2 .2
' -thiodiethylenebis[3- (3.

5-di-t-butyl-4-hydroxyphenyl)propionate], 1,6-hexanediol bis[3- (
3.5-di-t-butyl-4-hydroxyphenyl)propionate 1, butylhydroxyanisole, dibutylhydroxyanisole, 1-[2-((3.5-di-tert-butyl-4-hydroxyphenyl)propionyloxy)ethyl] -4- [3-(3.5-di-tert-butyl-4-hydroxyphenyl)buOpionyloxy]-2.2.6.6-tetramethylbiveridyl and the like.

Group (n): Paraphenylenediamines N-phenyl-N'-isopropyl-p-phenylenediamine, N. N'-Gsec-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 and the like.

Group (III): Hydroquinones 2,5-di-t-octylhydroquinone, 2.

6-Sidodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2
-[-octyl-5-methylhydroquinone, 2-(2
-octadecenyl)-5-methylhydroquinone, etc.

(rV) group: organic sulfur compounds dilauryl-3,3'-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 can be used in carrier generation layers, carrier transport layers, or maintenance layers. Although it may be added to any layer, it is 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
~50 parts by weight, particularly preferably 5 to 25 parts by weight.

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, q-nitro phthalic anhydride,
4-nitrophthalic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, 0-dinitrobenzene, m-dinitrobenzene, 1.3.5-trinitrobenzene, varanitrobenzonitrile, Picryl chloride, quinone chlorimide,
Chloranil, brumanil, dichlorodicyanobarabenzoquinone, anthraquinone, dinitroanthraquinone, 2
, 7-dinitrofluorenone, 2.4.7-trinitrofluorenone, 2゜4.5.7-tetranitrofluorenone, 9-fluorenylidene [dicyanomethylene malonodinitrile], 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.

The amount of electron-accepting substance added is carrier-generating substance-'R clove-accepting substance-100: 0.01 to 200 in weight ratio;
Preferably the ratio is 100:0.1 to 100.

The electron-accepting substance may be added to the carrier transport layer. The addition m of the electron-accepting substance to such a layer is a weight ratio of carrier-transporting substance:electron-accepting substance-100=0.01 to 100.
, preferably 100:'0.1 to 50.

The photoreceptor of the present invention may also contain an ultraviolet absorber or the like for the purpose of protecting the photosensitive layer, if necessary, or a dye for color sensitivity correction.

The electrophotographic photoreceptor of the present invention has the above structure,
As is clear from the Examples described later, 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 by examples.
This does not limit the embodiments of the present invention.

Example 1 Vinyl chloride-vinyl acetate-
Maleic anhydride copolymer [Eslec MF-10J (
An intermediate layer with a thickness of 0.05 μm was provided, and 2 g of exemplified compound No. 12 and polycarbonate resin "Panlite L-12504 (manufactured by Yojin Kasei Co., Ltd.) 2 (] 1) were placed on top of it. .2-dichloroethane 1101A 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 that, a carrier transport layer was applied. As a material, the following structural formula (K-1) 60 was applied to polycarbonate resin "Panlite Shiichi 1250J 10 (+) dissolved in 1,2-dichloroethane 801Q so that the film thickness after drying was 15 μm. A carrier transport layer was formed in this manner, and a photoreceptor of the present invention was produced.

(K-1) The photoreceptor obtained as described above was subjected to the following characteristic evaluation using an electrostatic paper tester model SP-428 manufactured by Kawaguchi Electric. After charging for 5 seconds at a charging voltage of -6 kV, 5
Leave it in the dark for seconds, then increase the illuminance on the photoreceptor surface to 351ux.
The exposure amount required to attenuate the surface potential by half (half-reduced exposure amount) El by irradiating halogen lamp light so that
/2 was calculated. Also, exposure m of 30 lux-sec
The surface potential (residual potential) VR after exposure was determined. Further, similar measurements were repeated 100 times. The results are shown in Table 1.

Comparative Example 1 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 performed in the same manner as in Example 1, and the results shown in Table 1 were obtained.

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

Examples 2-4 Exemplary compound No. 107 as a carrier generating substance.

2.20 respectively, the following compounds were used as carrier transport substances, and the other conditions were the same as in Example 1.
When a photoreceptor of the present invention was prepared and the same measurements were performed, the results shown in Table 2 were obtained.

(K-2) (K-3) (K-4>C2μ% Table 2 Example 5 Aluminum was vapor-deposited on a polyester film, the intermediate layer used in Example 1 was provided, and exemplified compound N
2g of 0.77 and polycarbonate resin "Panlite L"
-1250J 2 Q and 1,2-dichloroethane 1
10112 and was dispersed for 8 hours using a sand grinder. This dispersion liquid was applied so that the film thickness when dried was 0.5 .mu.m to form a carrier generation layer. Furthermore, as a carrier transport substance, the following structural formula (K-5) 6a was added to a polycarbonate resin "Panlite 11300 J (manufactured by Yojin Kasei Co., Ltd.) 10 g dissolved in 801 g of 1,2-dichloroethane. After drying, A carrier transport layer was formed by coating to a film thickness of 15 μm, and a photoreceptor of the present invention was manufactured.

(K-5> The same measurements as in Example 1 were performed on this photoreceptor, and the results are shown in Table 3.

Comparative Example 2 An electrophotographic photoreceptor was produced in the same manner as in Example 5, except that a stilbene azo pigment represented by the following structural formula (G-2) was used as a carrier-generating substance.

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

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 6 to 8 Vinyl chloride-vinyl acetate-
Maleic anhydride copolymer [S-LEC MF-10J
(manufactured by Block Chemical Co., Ltd.) with a thickness of 0.05 μm was provided, and on top of that, Exemplified Compound No. 14.20 and polycarbonate resin “Panlite L-1250J 2 o” were added to tetrahydrofuran 80- , 12 in a ball mill
Spread out time. The film thickness when drying this dispersion was 0.5 μ-
6 g of each of the compounds represented by the following structural formulas (K-6, ni-7, ni-8) and a polycarbonate resin rZ- 200J (manufactured by Mitsubishi Gas Chemical)
100 dissolved in 1,2-dichloroethane 80112 was applied so that the film thickness after drying was 15 μl,
A carrier transport layer was formed to produce a photoreceptor of the present invention.

(K-7) (K-8) The same measurements as in Example 1 were performed, and the results shown in Table 4 were obtained.

Table 4 Example 9 The surface of an aluminum drum with a diameter of 60 mm was coated with vinyl chloride-vinyl acetate-maleic anhydride copolymer "S-LEC MF-10J (Sekisui Chemical Co., Ltd. vJ) with a thickness of 0.
A 05 μm intermediate layer is provided on which the exemplified compound NO.4 is applied.
3,20 and polyester resin [By0n 200J (
Toyobo Co., Ltd.) 2g and 1,2-dichloroethane 80-
The dispersion liquid was mixed with a ball mill and dispersed for 24 hours using a ball mill dispersion machine.
A carrier generation layer was formed.

On top of the colander, 30 g of the following compound (K-9) and 50 g of polycarbonate resin "Niepiron 3-1000J (manufactured by Mitsubishi Gas Chemical Co., Ltd.) were added to 4 oo1 of 1,2-dichloroethane.
A drum-shaped photoreceptor was prepared by dissolving the carrier transport layer in 12 and coating it to a dry film thickness of 18 μm.

(K-9) The photoreceptor thus prepared is transferred to an electrophotographic copying machine r U
-B ix1550M RJ (Roku Konishi Photography a)
When it was installed on a modified machine manufactured by the company, and the images were copied, the resulting copied images were high in contrast, faithful to the original, and clear. Moreover, this did not change even after repeating 10,000 times.

Comparative Example 3 A drum-shaped comparative photoreceptor was prepared in the same manner as in Example 9, except that an azo compound represented by the following IN formula (G-3) was used as the carrier generating substance. When the copied images were evaluated, only images with a lot of fog were obtained. Moreover, as the copying process is repeated, the contrast of the copied image decreases, and the copied image cannot be printed even if the copying process is repeated s, ooo times.

(G-3) Example 10 Vinyl chloride-vinyl acetate-
Maleic anhydride copolymer “S-LEC MF-10J (
An intermediate layer with a thickness of O and OSμ- is provided, and the intermediate layer is made of a material with the following structural formula (K-
10) and 10 g of polycarbonate resin “Panlite L-1250J” were mixed with 8 g of 1,2-dichloroethane.
A carrier transport layer was formed by applying a solution dissolved in 01ρ so that the film thickness after drying was 15 μl.

(K-10) Furthermore, exemplified compound No. 18.20, the above carrier transport substance t, sg, polycarbonate resin "Panlite L-1250J2Q" and 1.2-dichloroethane 70*(l and 1.1 .2-Trichloroethane 30
- In addition, apply a dispersion liquid using a ball mill for 24 hours,
A photoreceptor was prepared by providing a carrier generation layer having a thickness of 4 μm after drying.

When this photoreceptor was measured in the same manner as in Example 1, the results shown in Table 5 were obtained.

As is clear from the results of the Examples and Comparative Examples shown in Table 5 and above, the photoreceptor of the present invention has better characteristics than the comparative photoreceptor, such as stability, sensitivity, durability, and combination with a wide range of carrier transport substances. It is extremely superior in terms of performance.

[Brief explanation of the drawing]

FIGS. 1 to 6 are cross-sectional views showing structural examples of the photoreceptor of the present invention, respectively. 1... Conductive support 2... Carrier generation layer 3.
...Carrier transport layer 4...Photosensitive layer 5...Intermediate layer 6...Layer containing carrier transport substance 7...Carrier generating substance

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] ▲Mathematical formulas, chemical formulas, tables, etc.▼ [In the formula,
It represents an alkoxy group, a trifluoroalkyl group, or a cyano group, and R_2 represents a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group. Z represents an atomic group necessary to constitute a carbocyclic aromatic ring or a heterocyclic aromatic ring. Y is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ Mathematical formulas, chemical formulas , table, etc. Represents ▼. ] (2) The photosensitive layer contains a carrier transporting substance and a carrier generating substance, and the carrier generating substance has the general formula [I
The electrophotographic photoreceptor according to claim 1, which is a bisazo compound represented by the following. (3) 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. Electrophotographic photoreceptor.