JPS60111247A - Photosensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity and stability by incorporating a specified tetrakisazo compd. CONSTITUTION:A carrier generating layer 2 formed on a conductive substrate 1 is composed essentially of a tetrakisazo compd. represented by formula I in which X1-X4 are each H, halogen, 1-4C alkyl or alkoxy; A is formula II, III, or IV; in formula II Y is carbamoyl or sulfamoyl; Z is an atomic group necessary to form an aromatic carbon or hetero ring; in formula III, R1 is H, 1-4C alkyl, amino, carboxy, its ester, carbamoyl, or cyano; R2 is an aromatic carbon ring group; and in formula IV, R3 is 1-4C alkyl, aralkyl, or an aromatic carbon ring group. A photosensitive layer 4 is formed by laminating a carrier transfer layer 3 composed essentially of a carrier transfer material on said carrier generating layer 2. As a result, the obtained electrophotographic sensitive body is stable against heat and light, superior in electrostatic charging characteristics, sensitivity, residual potential, etc., and sufficiently high in sensitivity to a long wavelength light source.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a photoreceptor, and more particularly to a novel electrophotographic photoreceptor containing a tetrakisazo compound.

(Prior Art) Conventionally, photoreceptors having a photosensitive layer mainly composed of an inorganic photoconductor such as selenium, zinc oxide, or cadmium oxide have not been widely used. However, these were not necessarily fully satisfactory in terms of sensitivity, heat resistance, printing durability, etc.

On the other hand, in recent years, electrophotographic photoreceptors having a photosensitive layer containing an organic photoconductive compound as a main component have attracted attention. They are relatively easy to manufacture, can be used in cylindrical drum, sheet, and ftL shapes, have many advantages such as low manufacturing cost, easy handling, and excellent heat resistance. However, for example, poly-N-vinylcarbazole, which has been put into practical use in
4゜7-) In an electrophotographic photoreceptor having a layer mainly composed of a charge transfer complex formed from a Lewis acid such as IJ nitro-9-fluorene, sensitivity and printing durability are essential. However, I have not been able to obtain satisfactory results.

However, with the invention of functionally separated electrophotographic photoreceptors such as laminated type or dispersion ridge type in which the carrier generation function and carrier transport function are shared by separate substances from the viewpoint of photoconductive function, various types of electrophotographic photoreceptors have been developed. advantages have emerged. These functional type IIIA electrophotographic photoreceptors have a wide range of materials to choose from, and are relatively easy to achieve high performance in terms of electrophotographic properties such as charging characteristics, sensitivity, and residual potential, as well as printing durability. It has the advantage that it is easy to create an electrophotographic photoreceptor with desired characteristics.

Various inorganic and organic substances have been proposed as carrier-generating substances that primarily take charge of carrier generation in function-separated electrophotographic photoreceptors having such advantages. As an inorganic material, a carrier generation layer formed from amorphous selenium is well known, but this has the disadvantage that it crystallizes under high temperature conditions and its performance deteriorates. Furthermore, among photoconductive organic dyes and pigments, various organic substances have been proposed to be used as carrier-generating substances.
No. 033, JP-A-53-132347, JP-A-Sho FIFI-69148, JP-A-56-1160
Azo compounds such as those described in JP-A No. 40 and JP-A-57-200045 are already known. However, these azo compounds are not necessarily satisfactory in terms of characteristics such as sensitivity, residual potential, and stability upon repeated use. In addition, the current situation is that a material that fully satisfies the wide range of requirements of electrophotographic processes, such as the selection range of carrier transporting substances, has not yet been obtained.

Furthermore, in recent years, Ar laser, He
Gas lasers such as -Ne lasers and semiconductor lasers are beginning to be used. These lasers are turned on in chronological order
Copiers and computer output printers that have image processing functions such as intelligent copiers that are capable of 10FF, high-speed, high-resolution recording, and the ability to diversify recording formats. It is seen as particularly promising as a light source. Among these, semiconductor lasers are attracting attention because their nature does not require an electrical signal/optical signal conversion element such as an acousto-optic element, and the device can be made compact and compact.

However, this semiconductor laser has a low output power compared to a gas laser, and the oscillation wavelength is also long (approximately 780 nm).
(above), the spectral sensitivity of conventional photoreceptors is too short for short wavelengths, and it is impossible to use them as photoreceptors using semiconductor lasers as light sources.

(Objective of the Invention) An object of the present invention is to provide an electrophotographic photoreceptor containing a tetrakisazo compound that is stable to heat and elements and has excellent carrier generation ability.

Another object of the present invention is to provide high sensitivity, low residual potential,
It is also 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 tetrakisazo compound that can effectively act as a carrier generating substance even in combination with a wide variety of carrier transporting substances.

Still another object of the present invention is to provide a photoreceptor having sufficient practical sensitivity even to long wavelength light sources such as semiconductor lasers.

(Structure of the Invention) In order to achieve the above object, the present inventors have conducted intensive research and found that a tetrakisazo compound represented by the following general formula (1) can act as an active ingredient of a photoreceptor. Inside, x, xl, xs, and x4 are each a hydrogen atom, a halogen atom (chlorine atom, bromine atom, iodine atom, or fluorine atom), or an alkyl group having 1 to 4 carbon atoms (including saturated O unsaturated ones. For example, Methyl group, ethyl group, indole ring, n-
butyl group, vinyl group, etc.), alkoxy groups having 1 to 4 carbon atoms (including saturated and unsaturated ones; for example, methoxy group, ethoxy group, ls).

-propoxy group, n-butoxy group, vinyloxy group, etc.)
represents.

Preferably it represents a hydrogen atom.

A is Rs R21 υ R4 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (saturated,
Contains unsaturated ones. For example, methyl group, ethyl group, 1s
o-propyl group, n-butyl group, vinyl group, etc.), p, nyl group, aralkyl group (eg 1-benzyl group, 7-enethyl group, etc.).

Preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (including saturated and unsaturated ones, such as a methyl group, an ethyl group,
(lll0-propyl group, n-butyl group, vinyl group, etc.), and more preferably a hydrogen atom.

R1 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (including saturated and unsaturated, specific examples are the same as above for R4K), an aralkyl group (for example, same as above for R), an aromatic carbocyclic group (for example, a 71-nyl group) , naphthyl group, anthryl group, etc.) or an aromatic heterocyclic group (eg, carbazolyl group, dibenzofuryl group, etc.).

Preferably, it represents an aromatic carbocyclic group (examples are the same as above), an aromatic heterocyclic group (examples are the same as above), and more preferably an aromatic carbocyclic group (examples are the same as above).

2 is an atomic group necessary to form an aromatic carbocycle or aromatic heterocycle, and specifically, an atomic group forming a benzene ring, a naphthalene ring, an indole ring, a pensono 2 ring, a carbazole ring, etc. represents, but is not limited to this.

Bird is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (for example, s R
4), amine groups (e.g., amino groups, methylamino groups, anilino groups, etc.), carboxy groups, and their ester groups (
For example, ethoxycarbonyl group, pentylcarbonyl group, etc.), carbamoyl group (Example L: N-methylcarbamoyl group, N-phenylcarbamoyl group, etc.), cyano group, preferably 1° hydrogen atom, carbon number 1-4 are an alkyl group (the example is the same as R4) and a cyan group.

R1 is an aromatic carbocyclic group, preferably a phenyl group.

R3 is an alkyl group having 1 to 4 carbon atoms (for example, an aralkyl group as shown above for R4 (for example, same as above for R4), or an aromatic carbocyclic group (for example, same as for R5), preferably an alkyl group having 1 to 4 carbon atoms. an alkyl group (examples are as above), and an aromatic carbocyclic group (examples are as above).

These X, , X,, X,, X,, R,, R,
,R,,R,,R,.

The series of groups or rings listed in 2 may have the following substituents in addition to the above-mentioned unsubstituted groups. That is, for example, alkyl groups having 1 to 4 carbon atoms (including saturated and unsaturated ones; examples are the same as those described for R4), halogen atoms (
chlorine atom, bromine atom, fluorine atom, iodine atom), carbon number 1
~4 alkoxy groups (including saturated and unsaturated ones, such as methoxy group, ethoxy group, l5o-propoxy group, f
lee-butoxy group, allyloxy group, etc.), hydroxy group, arylox group (e.g., phenoxy group, naphthoxy group, etc.), acyloxy group (e.g., acetyloxy group,
penzoyloxy group, etc.), carboxy group, its ester group (e.g., ethoxycarbonyl group, phenoxycarbonyl group, etc.), carbamoyl group (e.g., N-methylcarbamoyl M, N-phenylcarbamoyl group, etc.), acyl group (
For example, acetyl group, benzoyl group44), sulfo group,
Sulfamoyl group (e.g. N-ethylsulfamoyl group, N-naphthyl, sulfamoyl group, etc.), amino group (
For example, amine group, dimethylamino group, anilino group, etc.),
Acylamino groups (e.g. acetylamino groups, benzoylamino groups, etc.), sulfonamide groups (e.g. methanesulfonamide groups, benzenesulfonamide groups, etc.), cyano groups, nitro groups, aromatic carbocyclic groups (e.g. phenyl groups, naphthyl groups, etc.) ), aromatic heterocyclic groups (e.g. oxacylyl group,
Examples include imidazolyl group.

Preferably, an argyl group having 1 to 4 carbon atoms (examples are the same as above), a halogen atom (examples are the same as above), and 1 to 4 carbon atoms.
an alkoxy group (examples are the same as above), a cyan group, and a nitro group.

The series of substituents listed above may be further substituted with substituents such as the series of groups listed above.

That is, in the present invention, by using the tetrakisazo compound represented by the general formula 1J as a photoconductive substance constituting the photosensitive layer of an electrophotographic photoreceptor, or by using only the excellent carrier generation ability of the tetrakisazo compound of the present invention. By using this with the carrier generating material of the pi @ type electrophotographic photoreceptor, which generates and transports carriers using separate substances, it is possible to achieve stable characteristics in KW cells such as thermal light. It is possible to produce an electrophotographic photoreceptor that has excellent electrophotographic properties such as durability, band WL%, sensitivity, and residual potential, and printing durability, and has sufficient sensitivity to a long wavelength light source.

(Structure of the Invention) Examples of the tetrakisazo compound useful in the present invention represented by the general formula [0] include those having the following structural formula; It can be easily synthesized by known methods.

Synthesis Example 1 (Synthesis of Exemplary Compound (A-1)) J, Med
, Pharm, Chem, 1.197-211
(1957), 4,4'-dinitrodiphenylamine and 4,4'-short piphenyl were condensed in nitrobenzene in the presence of copper powder and potassium carbonate to obtain N.

N, N: N'-tetrakis(p-nitrone-nyl)-4
s4 diamino bifunyl was obtained. Reduced with iron and hydrochloric acid in N,N-dimethylformamide by a conventional method.
, N, N'.

N'-tetrakis(p-aminophenyl)-4,4'-
Diaminobiphenyl was obtained. Thus obtained N, N, N'
, N'--tetrakis(p-aminophenyl) -4,
5.5 g (0.01 mol) of 4'-diaminobiphenyl was dispersed in 100 m of 6N hydrochloric acid, and 3.0 F (0.044 mol) of nitrite sorter was added to the mixture while stirring and maintaining the temperature at 0 to 5°C. An aqueous solution dissolved in 20 ml of water was added dropwise, and stirring was continued for 1 hour at the same temperature.

After that, 3.0 g of urea was added to decompose unreacted sodium nitrite, a small amount of residue was filtered off, 42% borohydrogen fluoride fi30d was added to the filtrate, and the precipitate was collected by filtration. After washing with water, it was dried. The obtained octazonium salt was dissolved in N,N-dimethylformamide lfiQgm under cooling.

Add 2-hydroxy-3-naphthoanilide (
Naphthol As) 10. After adding fl (0.04 mol) to an internal temperature of 5 to 10°C and dissolving it, 11.9 g of triethanolamine (O, O
A solution prepared by dissolving 704 of N,N-dimethylformamide (S mol) was added dropwise while stirring while maintaining the internal temperature at 5 to 10°C.

After the dropwise addition, the mixture was stirred at the same temperature for 1 hour, and then stirred and reacted at room temperature for 3 hours. After that, the precipitate that precipitated was collected by filtration, and 1.5e
12.5 g of the target tetrakisazo compound was obtained by washing twice with 1 liter of N,N-dimethylformamide and once with 1 liter of acetone and drying.

Yield: 76% Melting point: 300° C. or higher In the infrared absorption spectrum, amide absorption appeared at ν=1680 cIrL” and from the following elemental analysis results, it was confirmed that an ordinary tetrakisazo compound was synthesized.

Elemental analysis calculated value Observed value C (%) 75.90 75.74 H (%) 4゜41 4.7O N (%) 11.92 11.83 Synthesis example 2 (synthesis of exemplified compound (A-31)) N, N, N', N'-tetrakis (p
-aminophenyl) -4,4'-diaminobifuranyl 5.5 g (0.01 mol) at 100 mA! Dispersed in 06N hydrochloric acid, stirred and maintained at θ ~ 5°C, 3.0 g' (
A cold aqueous solution of 20 ml of sodium nitrite (0,044 mol) dissolved in water was added dropwise, and stirring was continued for 1 hour at the same temperature.

After that, 3.0 g of urea was added to decompose unreacted sodium nitrite, a small amount of residual liquid was filtered off, 42% borohydrofluoric acid aOm was added to the filtrate, and the precipitate was collected by filtration. death,
After washing with water, it was dried.

The obtained octazonium salt was dissolved in N,N-dimethylformamide 1500-200 ml while cooling.

To this solution was added 5 mols of 2-hydroxy-3-(4-methoxyphenylcarbamoyl)benzo(t)carbasol (su7tolhs-8a)-14,9f (0.04 mol).
After adding and dissolving at an internal temperature of ~10°C, a solution of 6 = 511 (o, 8 mol of o) of sodium acetate, which had been prepared in advance, dissolved in 7°d water was heated to a temperature of 5 to 10°C. The mixture was added dropwise while stirring while maintaining the internal temperature.

After the dropwise addition, the mixture was stirred at the same temperature for 1 hour, and then stirred and reacted at room temperature for 3 hours. Thereafter, the precipitate precipitated was collected by filtration, washed twice with ig water, then twice with 11f) N,N-dimethylformamide, then once with le acetate, and dried. 8.91 of the azo compound was obtained.

Yield: 42% Melting point: 300°C or higher The infrared absorption spectrum shows amide absorption at ν = 1680 cm-' and the following elemental analysis results indicate that the desired tetrakisazo compound will not be synthesized. Elemental analysis calculated value Observed value C ( %) 74.70 74.61 H (%) 4.37 4.51 N (%) 11.88 11.94 The photosensitive layer of the electrophotographic photoreceptor of the present invention is formed by the tetrakisazo compound represented by the general formula (I). may be used as a carrier-generating substance constituting the compound, and may be combined with a carrier-transporting substance having a carrier-transporting ability to provide a so-called functionally separated photosensitive layer of a laminated type or a dispersed type. Regarding the composition of the photosensitive layer,
It is also possible to use not only one type of tetrakisazo compound represented by the general formula CI') but also a combination of two or more types, or in combination with another tetrakisazo compound or other carrier-generating substance.

The coupler components represented by A above may be appropriately combined to form a tetrakisazo compound with a plurality of types of Kab2-components.

8! Electrophotographic photoreceptor of the present invention! In the case of a functionally separable type, the mechanical configuration may be any of the 19 conventionally known configurations. Usually, the configuration is as shown in FIGS. 1 to 6.

1 and 3 are laminates of a conductive support 1, a carrier generation layer 2 containing the above-mentioned tetrakisazo compound as a main component, and a carrier transport layer 3 containing a carrier transport substance as a main component. A second structure including a photosensitive layer 4 consisting of
4 have a structure in which an intermediate layer 5 is interposed between the conductive support l and the photoreceptor M4 in the structure shown in FIGS. 1 and 3, respectively. As described above, the best electrophotographic properties can be obtained when the photosensitive layer 4 has a two-layer structure. In the case shown in FIG. 5, a photosensitive layer 4 formed by medium-pressure dispersion of a layer 6 containing the above-mentioned tetrakisazo compound as a main component, which is a carrier transport substance, is directly applied onto a conductive support l. The provided structure, shown in FIG. 6, is a structure in which a photosensitive layer 4 similar to that shown in FIG. 5 is provided on a conductive support l with an intermediate layer 5 interposed therebetween.

Examples of the carrier transporting substance include electron-transporting electron-accepting substances such as trinitrofluorenone and tetranitrofluorenone, or heavy metals having a heterocyclic compound in the side chain, such as poly-N-vinylcarbazole. conjugation, triazole derivatives, oxadiazole derivatives, imidazole conductors, pyrazoline derivatives, polyarylalkane visiting conductors, phenylene thione derivatives, hydrazone conductors, amino-substituted chalcone derivatives, triarylamine derivatives, carbazole derivatives, stilbene derivatives, etc. Examples include hole-transporting electron-donating substances, but the carrier-transporting substances used in the present invention are not limited to these.

When forming a two-layered photosensitive layer, the carrier generation layer 2 can be provided by the following method.

(a) A method of applying a solution prepared by dissolving the above-mentioned tetrakisazo compound in a suitable solvent, or a solution obtained by adding a binder to the solution and mixing it.

(b) A method of forming the aforementioned tetrakisazo compound into fine particles in a dispersion medium using a ball mill, a homomixer, etc., and applying a dispersion obtained by mixing and dispersing with a binder added as necessary.

Solvents or dispersion media used to form the carrier generation layer include n-butylamine, diethylamine, ethylenediamine, impropaturamine, triethanolamine, triethylenediamine, N,N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, and benzene. , toluene, xylene, chloroform,
Examples include 1,2-dichloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and the like.

When a binder is used to form a carrier generation layer or a carrier transport layer, any binder can be used, but it is particularly suitable for forming an electrically insulating film that is hydrophobic and has a high dielectric constant. High molecular weight polymers are preferred. Examples of such polymers include, but are not limited to, the following:

a) Polycarbonate b) Polyester C) Methacrylic resin d) Acrylic resin e) Polyvinyl chloride f) Polyvinylidene chloride g) Polystyrene h) Polyvinyl acetate I) Styrene-butadiene copolymer j) Vinylidene chloride-acrylonitrile copolymer k) Vinyl chloride-vinyl acetate copolymer l) Vinyl chloride-vinyl acetate-maleic anhydride copolymer m) Silicone resin n) Silicone-alkyd resin 0) Phenol-formaldehyde resin p) Styrene-alkyd resin q) Poly- N-vinylcarbazole r) Polyvinyl butyral These binders can be used alone or in a mixture of two or more.

The thickness of the carrier generation layer 2 formed in this way is 0.
．． It is preferably 0.01 to 20 μm, more preferably 0.01 to 20 μm. (IF 1 to 5 μm. In addition, in the case where a photosensitive layer or a carrier generation layer is formed by fractionating the tetrakisazo compound described above, the tetrakisazo compound is a powder with a particle size of 5 μm or less, preferably 1 μm or less. It is preferable that

The conductive support in the present invention may be a metal plate, a metal drum, or a conductive thin layer made of a conductive polymer, a conductive compound such as indium oxide, or a metal such as aluminum, palladium, or gold, by coating, vapor deposition, lamination, etc. A material provided on a substrate such as paper or a plastic film is used. The intermediate layer which functions as an adhesive layer or a barrier layer may be made of a polymer having a tN content such as a binder or a polymer as described above, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, or aluminum oxide. used.

(Effects of the Invention) The photoreceptor of the present invention has the above structure, and by using the tetrakisazo compound represented by the general formula CII as a photoconductive substance constituting the photolayer, IN<of the photoreceptor. , or by utilizing only the excellent carrier generation ability of the tetrakisazo compound of the present invention and performing carrier generation and transport using separate substances, a carrier generation material for a five-functionally separated electrophotographic photoreceptor. By using it as a material, it exhibits robust and stable properties under thermal imaging, etc., and has electrophotographic properties such as physical properties of the film, charging properties, sensitivity, and residual potential, as well as low fatigue deterioration even after repeated use, and printing durability. It is possible to create an electrophotographic photoreceptor with excellent properties.

Further, the electrophotographic photoreceptor of the present invention can be used for long wavelength light (~780n).
As a photoreceptor, it has good sensitivity not only to ordinary copiers but also to long-wavelength light sources such as semiconductor lasers, and is used for electrophotography such as laser printers and laser hook stains. Can be used widely in applied fields.

(Example) Examples of the present invention will be explained in detail, but the embodiments of the present invention are not limited thereby. Vinyl chloride - vinyl acetate - on a conductive support
Maleic anhydride copolymer [S-LEC MF-10J (
An intermediate layer with a thickness of 0.05 μm was provided, and 2 parts by weight of Exemplified Compound (A-3) was added thereon at 1,2-
A carrier-generating layer was formed by dispersing and mixing a solution in 140 parts by weight of dichloroethane and applying the solution to a dry film thickness of 0.5 μm.

Next, 6 parts by weight of l-phenyl-3-(p-diethylaminostyryl)-5-(p-diethylaminophanyl) pyrano 9F and 10 parts by weight of polyester [Vylon 200J (manufactured by Toyobo Co., Ltd.)] were mixed with 1,2-dichloroethane ( stomach)
The film thickness after drying this solution is 10 μm.
A carrier transport layer was formed by coating the powder to form an electrophotographic photoreceptor of the present invention.

Regarding this electrophotographic photoreceptor, the electrostatic copying paper tester rP
The electrophotographic characteristics were measured using a dynamic method using "Model S-428" (manufactured by Kawaguchi Electric Seisakusho).

The surface potential VA when the surface of the photosensitive layer of the photoreceptor was charged for 5 seconds at a charging voltage of -6, OKV.Then, the surface potential was determined by irradiating light from a tungsten lamp so that the illuminance at the surface pressure of the photoreceptor was 351 ux. Exposure amount required to attenuate VA by half (half-reduced exposure amount)] IE3A (Iux*
The surface potentials (residual potentials) VR were determined after applying g with an exposure dose of ssc) and 301 uxamac.

Further, similar measurements were repeated 100 times.

The results are shown in Table 1.

Table 1 Comparative Example 1 A comparative photoreceptor was prepared in the same manner as in Example 1 except that the following trisazo compound was used as a carrier generating substance.

When this comparative electrophotographic photoreceptor was measured in degrees Celsius in the same manner as in Example 1, the results shown in Table 2 were obtained.

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

Example 2 An electrophotographic photoreceptor of the present invention was produced in the same manner as in Example 1, except that exemplified compounds (A-J, ) were used as carrier-generating substances.

When this electrophotographic photoreceptor was measured in the same manner as in Example, the results shown in Table 3 were obtained.

Table 83 Example 3 Aluminum was deposited on a polynisder film, the intermediate layer used in Example 1 was provided, and 2 parts by weight of Exemplified Compound (A-7) was added to 140 M of 1.2-dichloroethane.
A carrier-generating layer was formed by dispersing and mixing a portion of the liquid and applying the solution to a dry film thickness of 0.5 μmK.

Next, 6 parts by weight of p-(NpN-diethylamino)benzaldehyde-1,l-diphenylhydrazone and 10 parts by weight of polycarbonate [Panlite L-1250J (Teijin Kasei Co., Ltd. $1!) were added to 1p2-dichloroethane by weight. The film thickness after drying the solution dissolved in
A carrier transport layer was formed by coating the powder to form an electrophotographic photoreceptor of the present invention.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, VA = -720V, v34
=1.9 lux fistsee, VB=OV.

Comparative Example 2 The same measurements as in Example 1 were carried out on this comparative electrophotographic photoreceptor in the same manner as in Example 3 except that the following trisazo compound was used as a carrier generating substance. VA = -F )10V.

8%:=6.81uxssec, VR=-15V
Met.

As is clear from the above results, the electrophotographic photoreceptor of the present invention has significantly superior initial characteristics than the comparative electrophotographic photoreceptor.

Example 4 The electrophotographic photoreceptor of the present invention according to Example 3 and the comparative electrophotographic photoreceptor according to Comparative Example 2 were each used in an electrophotographic copying machine "U".
- Bix 2000RJ (manufactured by Konishiroku Photo Industry Co., Ltd.) was used to perform charging, exposure, and cleaning operations at 10.0
Immediately after carrying out the durability test 00 times, the same measurements as in Example 1 were carried out again. The results are shown in Table 4.

Table 4 Characteristics after 10,000 cycles of durability test As is clear from the results, the electrophotographic photoreceptor of Comparative Example 2 had significantly deteriorated characteristics, while the electrophotographic photoreceptor of Example 30 of the present invention had the following characteristics: It can be seen that even after 10,000 charging-exposure cycles, the characteristics remained stable with almost no change from the initial state.

Example 5 The exemplified compound (A-1
0) 2Ji parts and polycarbonate [Panlite L-
A carrier generation layer was formed by coating a solution prepared by dispersing and mixing 2 parts by weight of 1250J (Teijin Kasei Co., Ltd.) in 140 parts by weight of 1,2-dicycloethane so that the film thickness after drying was 1 μm.

Next, 6 parts by weight of 3-(p-methoxystyryl)-9-cp-methoxyphenyl)carbazole and 10 parts by weight of methacrylic resin "Acrivet" (manufactured by Mitsubishi Ray 3F Co., Ltd.) were mixed with 1,2-dichloroethane (3 parts by weight). ) A carrier transport layer was formed by applying a solution dissolved in 5 parts by weight to a film thickness of 10 μm after drying to form an electrophotographic photoreceptor of the present invention.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, E%=2.1 1ux"sse, Vn=(
) It was V.

Example 6 A 2% ethylenediamine solution of exemplified compound (A-13) was coated on the conductive support provided with the intermediate layer used in Example 1 so that the film thickness after drying was 0.3 μm to generate carriers. formed a layer.

Furthermore, 1-phenyl-3-(p-diethylaminostyryl)-fi-(p-diethylaminophenyl)
6 parts by weight of pyrazoline and 10 parts by weight of polycarbonate [Nipiron 8-1ool (manufactured by Mitsubishi Gas Chemical Co., Ltd.)]
, was dissolved in 90 parts by weight of 2-dichloroethane, and coated to form a carrier transport layer to a film thickness of 14 μm after drying, thereby producing an electrophotographic photoreceptor of the present invention.

When this electrophotographic photoreceptor was measured in the same manner as in Example 1, E% = 1.81 ux sea, V
n=Ov〇Also, this electrophotographic photoreceptor was used in an electrophotographic copying machine [U-B
After copying the image, a clear copy image faithful to the original, with high contrast, and excellent gradation was obtained. Even if this was repeated io, ooo times, the same copy image as the initial one was obtained.

Example 7 A film made of vinyl chloride-vinyl acetate-maleic anhydride copolymer "Esle MF-10J" (manufactured by Block Chemical Co., Ltd.) with a thickness of 0.0 mm was deposited on a polyester film on which aluminum was vapor-deposited.
An intermediate layer of 05 μm was provided, and the exemplified compound (A-6
), 6 parts by weight of 4,4'-dimethyltriphenylamine, and polycarbonate [Panlite L-125
Add 10 parts by weight of 0J (manufactured by Ryotaikasei Co., Ltd.) to 100 parts by weight of 1,2-dichloroethane, and use a ball mill. An electrophotographic photoreceptor was prepared.

Regarding this electrophotographic photoreceptor, the electrostatic copying paper tester "s"
The electrophotographic properties were measured by the dynamic method using p-, izsya J (manufactured by Kawaguchi Electric Seisakusho).

The surface of the photosensitive layer was charged at +6 KV for 5 seconds, and then the light from a tungsten lamp was applied to the surface of the photosensitive layer at an illuminance of 35 b.
Irradiate in such a way that
As a result, E%=1.91ux@s+@e, and the surface potential (residual potential) when an exposure amount of 301ux@see was applied was VR=OV.

Example 8 The surface of an aluminum drum with a diameter of 100 snts was coated with vinyl chloride-vinyl acetate-maleic anhydride copolymer [ESLE, MF-10J (Sekisui Chemical Co., Ltd. #1, thickness 0.0
A 5 μm intermediate layer is provided, and exemplified compound (A-4) is placed on top of the intermediate layer.
4.9 was mixed with 400 d of 1,2-dichloroethane, and a dispersion liquid was dispersed in a ball mill dispersion machine for a period of time, and a dispersion liquid was applied so that the film thickness after drying was 0.6 μm to form a carrier generation layer.

Furthermore, on top of K, N is represented by the following structural formula.

30 g of N-diethylaminobenzaldehyde-1,1-diphenylhydrazone and polycarbonate resin "Nipilon S-1000J"
Mitsubishi Gas Chemical Co., Ltd.) 50.9 was dissolved in 400 d of 1,2-dichloroethane and coated to form a carrier transport layer so that the film thickness after drying was 13 μm VC, and a drum-shaped electrophotographic photoreceptor was created. did.

The photoreceptor produced in this way was used in an electronic copying machine [U-Bl].
When I installed it on a modified xV2J (manufactured by Konishiroku Photo Industry Co., Ltd.) and copied images, I was able to obtain clear copied images with high contrast and faithfulness to IJx images.

Moreover, this did not change even if it was repeated i o, o o o times.

Comparative Example 3 Example 8 except that the exemplary compound (A-4) in Example 8 was replaced with a trisazo compound represented by the following structural formula.
A drum-shaped comparative electrophotographic photoreceptor was prepared in the same manner as in Example 8, and the copied images were evaluated in the same manner as in Example 8. Only images with a lot of fog were obtained. Also, as copying is repeated, the contrast of the copied image decreases, and
If you repeat this 0,000 times, you will not be able to obtain a duplicate image.

Example 9 A vinyl chloride-vinyl acetate-maleic anhydride copolymer [ESLE, MF-10J (
An intermediate layer with a thickness of 0605 μm was provided, and 5 g of exemplified compound (A-15) and 3.3 fI of polycarbonate resin (Panrai) L-1250J (manufactured by Yondai Kasei Co., Ltd.) were added thereon in dichloromethane. In addition to 1001, the film thickness when dried is 10/
The electrophotographic photoreceptor was prepared by coating the film to give an electrophotographic photoreceptor.

The VR of the photoreceptor obtained as described above was measured to be 8% in the same manner as in Example 1, except that the charging voltage was changed to +6 KV. The first result is E% = 3.01ux book sea and V
R=-3V.

Example 10 A vinyl chloride-vinyl acetate-maleic anhydride copolymer [Esle,
MF-10J (manufactured by Tanezu Kagaku Co., Ltd.), thickness 0.05
Provide an intermediate layer of μm, and exemplified compound (A-34)
4g of ethane with 1,2-dichloro 400vtlK mixed,
A carrier-generating layer was formed by applying a dispersion that had been dispersed in a ball mill dispersing machine under pressure so as to have a dry film thickness of 0.5 μm.

Furthermore, p-(N#N-diethylamino)
Benzaldehyde-1,1-diphenylhydrazone 30
g and polycarbonate resin [Panlite L-1250j
(manufactured by Ryotai Kasei Co., Ltd.) in 400 ml of 1,2-dichloroethane and coated on the film to form a carrier transport layer so that the film thickness after drying becomes 12 μm. Created.

The spectral sensitivity of this photoreceptor at 780 times mK was o, so (half exposure amount).

Next, this photoreceptor is heated so that the laser light intensity on the surface of the photoreceptor is (1
, 85mW semiconductor laser (780nm)'
r: A live-action test was conducted using the experimental machine.

After the surface of the photoreceptor was charged to -6 KV, it was exposed to laser light and reversely developed at a bias voltage of -350 V. A good image without fog was obtained.

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

Examples 11 to 14 In Example 10, instead of Exemplified Compound (A-34),
Exemplified compound (A'''1) z (A-35) t (A
-''7) A drum-shaped photoreceptor was obtained in the same manner except that t (A-40) and (A-42) were used.

The spectral sensitivity of each photoreceptor at 780 mK was as shown in Table 5.

Table 5 Next, even in the actual photographing process using the experimental machine described in Example 10, each photoreceptor provided good IL images without fogging, and these did not change even after 10,000 repetitions.

As is clear from the above results, the photoreceptor of the present invention is extremely excellent in characteristics such as sensitivity and residual potential, and also in repeatability characteristics.

Furthermore, it is an excellent photoreceptor that is sufficiently practical in terms of sensitivity at long wavelengths and repetition stability.

[Brief explanation of drawings]

FIG. 6 is a sectional view showing an example of the mechanical structure of the electrophotographic photoreceptor of the present invention. 1... Conductive support 2... Carrier generation layer 3... Carrier transport layer 4... Photosensitive layer 5... Intermediate layer 6... Layer 7 containing a voice transport substance...・Carrier-generating substance agent Yoshimi Kuwahara Figure 1 - Figure 2 Figure 5 Ruiro

Claims (2)

[Claims] (1) A photoreceptor comprising at least one tetrakisazo compound represented by the following general formula [IJ] in a photosensitive layer on a conductive support. General formula [I] (where x, x, x3.X4: hydrogen atom, ISO'171M
Child, alkyl group having 1 to 4 carbon atoms or carbon A: υh 2: Atom group necessary to constitute aromatic carbon ring or aromatic heterocycle Y: Carbamoyl group or sulfamoyl group R8: Hydrogen atom, having 1 to 4 carbon atoms 4 alkyl group, amino group, cyan group, carbamoyl group, carboxy group or ester group thereof R, aromatic carbocyclic group R3 and R3': alkyl group having 1 to 4 carbon atoms, aralkyl group, aromatic carbocyclic group represents a group. ) (2) The photosensitive layer contains a carrier-generating substance and a carrier-transporting substance, and the carrier-generating substance is represented by the general formula [D
The photoreceptor according to claim (1), which is a tetrakisazo compound represented by: