JPH037939B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a photoreceptor, and more particularly to a novel electrophotographic photoreceptor having a photosensitive layer containing a bisazo compound. (Prior Art) Conventionally, inorganic photoreceptors having a photosensitive layer containing an inorganic photoconductive compound such as selenium, zinc oxide, or cadmium sulfide 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 decreases. 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, in Japanese Patent Publication No. 50-10496, poly-N-vinylcarbazole and 2,4,7-
There is a description of an organic photoreceptor having a photosensitive layer containing trinitro-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 functionally separated electrophotographic photoreceptors because each material can be selected from a wide range and a photoreceptor with arbitrary performance can be produced relatively easily. Ta. Many compounds have been proposed as carrier generating substances for such functionally separated electrophotographic photoreceptors. As an example of using an inorganic compound as a carrier generating substance, for example,
-There is amorphous selenium described in Publication No. 16198,
Although this is used in combination with an organic photoconductive compound, the drawback that the carrier generation layer made of amorphous selenium crystallizes due to heat and deteriorates the properties 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 an electrophotographic photoreceptor containing a bisazo compound or a trisazo compound in the photosensitive layer, JP-A-54-22834, JP-A-56-143437
Publication No. 138646, Japanese Patent Application Publication No. 1983-138646, Japanese Patent Application Publication No. 1983-
Publication No. 176055 and the like are already known. However, these bisazo compounds or trisazo compounds are
They do not necessarily satisfy the characteristics of sensitivity, residual potential, or stability during repeated use, and the selection range of carrier transport materials is also limited, so they do not fully satisfy the wide range of requirements of electrophotographic processes. do not have. Furthermore, in recent years, Ar laser has been used as a light source for photoreceptors.
Gas lasers such as He-Ne lasers and semiconductor lasers are beginning to be used. A characteristic of these lasers is that they can be turned on and off in a time-series manner, making them particularly promising light sources for copiers with image processing functions, such as intelligent copiers, and printers for computer output. 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 because they can be made smaller and lighter. However, this semiconductor laser has a low output compared to a gas laser, and the oscillation wavelength is also long (approximately 780 nm or more), so the spectral sensitivity of conventional photoreceptors is too high on the short wavelength side. It cannot be used as a photoreceptor using a laser as a light source. (Objective of the Invention) An object of the present invention is to provide a photoreceptor containing a specific bisazo compound that is stable against heat and light and has excellent carrier generation ability. Another object of the present invention is to provide an electrophotographic photoreceptor with high sensitivity, low residual potential, and excellent durability whose characteristics 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 transport 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. Still other objects of the present invention will become apparent from the description in the specification. As a result of extensive research to achieve the above object, the present inventors have discovered that a bisazo compound represented by the following general formula [] can act as an active ingredient of a photoreceptor, and have completed the present invention. be. General formula [] [However, in the formula, _Y1 and _Y2 : a group selected from a hydrogen atom, a halogen atom, a cyano group, an alkyl group, or an alkoxy group, A:

【formula】

【formula】

[expression] or

[Formula], Q is a substituted or unsubstituted carbamoyl group (

[Formula]), substituted and unsubstituted sulfamo yl group (

[Formula]), R ₄ : hydrogen atom, substituted/unsubstituted alkyl group having 1 to 4 carbon atoms, substituted/unsubstituted aralkyl group, substituted/unsubstituted phenyl group, R ₅ : hydrogen atom , substituted/unsubstituted alkyl groups having 1 to 4 carbon atoms, substituted/unsubstituted aromatic carbocyclic groups (e.g., substituted/unsubstituted phenyl groups, substituted/unsubstituted
(unsubstituted naphthyl group, substituted/unsubstituted anthryl group, etc.), or substituted/unsubstituted aromatic heterocyclic group (eg, substituted/unsubstituted carbazolyl group, substituted/unsubstituted dibenzofuryl group, etc.). Substituents for these groups include, for example, carbon atoms with 1
~4 substituted/unsubstituted alkyl groups (e.g. methyl group, ethyl group, isopropyl group, tertiary butyl group,
trifluoromethyl group, etc.), substituted/unsubstituted aralkyl groups (e.g., benzyl group, phenethyl group, etc.), halogen atoms (chlorine atom, bromine atom, fluorine atom, iodine atom), substituted/unsubstituted aralkyl groups with 1 to 4 carbon atoms. Substituted alkoxy groups (e.g., methoxy, ethoxy, isopropoxy, tertiary butoxy, 2-chloroethoxy, etc.), hydroxy groups, substituted/unsubstituted aryloxy groups (e.g., p-chlorophenoxy, 1- naphthoxy group, etc.), acyloxy group, carboxy group (e.g., acetyloxy group, p-cyanobenzoyloxy group, etc.), its ester group (e.g., ethoxycarbonyl group, m-bromophenoxycarbonyl group, etc.), carbamoyl group ( For example, aminocarbonyl group, tertiary butylaminocarbonyl group, anilinocarbonyl group, etc.), acyl group (e.g., acetyl group, o-nitrobenzoyl group, etc.), sulfo group, sulfamoyl group (e.g.,
aminosulfonyl group, tertiary butylaminosulfonyl group, p-tolylaminosulfonyl group, etc.), amino group, acylamino group (e.g., acetylamino group, benzoylamino group, etc.), sulfonamide group (e.g., methanesulfonamide group, p-tolylaminosulfonyl group, etc.) -toluenesulfonamide group, etc.), cyano group, nitro group, etc., but preferably substituted or unsubstituted alkyl groups having 1 to 4 carbon atoms (e.g., methyl group, ethyl group, isopropyl group, n-butyl group, trifluoromethyl group, etc.), halogen atoms (chlorine atom, bromine atom, fluorine atom, iodine atom), substituted/unsubstituted alkoxy groups having 1 to 4 carbon atoms (e.g. methoxy group, ethoxy group, tertiary butoxy group, 2-chloroethoxy group, etc.) cyano group, nitro group. Z is an atomic group necessary to form a substituted/unsubstituted aromatic carbocycle or a substituted/unsubstituted aromatic heterocycle, and specifically, for example, a substituted/unsubstituted benzene ring, a substituted/unsubstituted aromatic heterocycle, etc. Represents an atomic group forming an unsubstituted naphthalene ring, a substituted/unsubstituted indole ring, a substituted/unsubstituted carbazole ring, etc. Examples of substituent groups for the atomic groups forming these rings include a series of substituents such as those listed as substituents for R ₄ and R ₅ , but halogen atoms (chlorine atoms, bromine atoms, (iodine atom, fluorine atom), sulfo group, sulfamoyl group (for example, aminosulfonyl group, p-tolylaminosulfonyl group, etc.). R ₁ is a hydrogen atom, a substituted or unsubstituted alkyl group,
Substituted/unsubstituted amino group, carboxyl group, ester group thereof, substituted/unsubstituted carbamoyl group, cyano group, preferably hydrogen atom, carbon number 1-4
Substituted/unsubstituted alkyl groups (e.g., methyl group, ethyl group, isopropyl group, tertiary butyl group,
trifluoromethyl group, etc.) and cyano group. A′ is a substituted or unsubstituted aryl group, preferably a substituted or unsubstituted phenyl group, and a series of substituents such as those listed as substituents for R ₄ and R ₅ are listed as substituents for these groups. However, preferably halogen atoms (chlorine atom, bromine atom, fluorine atom, iodine atom), substituted or unsubstituted alkyl groups having 1 to 4 carbon atoms (for example, methyl group, ethyl group, isopropyl group, tertiary butyl group) group, trifluoromethyl group, etc.), and substituted/unsubstituted alkoxy groups having 1 to 4 carbon atoms (eg, methoxy group, ethoxy group, isopropoxy group, tertiary butoxy group, 2-chloroethoxy group). R ₂ and R ₃ represent a substituted/unsubstituted alkyl group, a substituted/unsubstituted aralkyl group, and a substituted/unsubstituted aryl group, preferably having 1 to 1 carbon atoms.
4 substituted/unsubstituted alkyl groups (e.g., methyl group, ethyl group, isopropyl group, tertiary butyl group,
trifluoromethyl group, etc.), substituted/unsubstituted phenyl group (e.g., phenyl group, p-methoxyphenyl group, m-florphenyl group, etc.). (Effects of the Invention) That is, in the present invention, by using a bisazo compound represented by the above general formula [] as a photoconductive substance constituting the photosensitive layer of a photoreceptor, heat and light resistance, which is the object of the present invention, can be achieved. It is stable and has excellent electrophotographic properties such as charge retention, sensitivity, and residual potential. It also shows little fatigue deterioration even after repeated use, and has sufficient sensitivity even in the wavelength region of 780 nm or more. It is possible to create a photoreceptor with (Structure-2 of the Invention) Among the bisazo compounds represented by the above general formula [] used in the present invention, atomic groups represented by the following general formulas [] and [] are preferred. General formula [] [In the formula, A, Y ₁ and Y ₂ are the same as the general formula []. ] General formula [ ] [In the formula, A, Y ₁ and Y ₂ are the same as the general formula []. ] Specific examples of the disazo compound useful in the present invention represented by the general formula [ ] include those having the following structural formula, but the disazo compound of the present invention is not limited by this. do not have.

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

The above bisazo compounds can be easily synthesized by known methods. Synthesis Example 1 (Synthesis of Exemplary Compound A-(1)) First, the outline of the synthesis route is shown below. That is, dinitro compounds 1 to 1 were reduced with tin in hydrochloric acid to give diamino compounds 2 to 1 according to JP-A-51-141632. This diamino form 2-33g (0.1 mol)
was added and dispersed in a mixture of 1.4 parts of concentrated hydrochloric acid and 0.7 parts of water, and a solution of 13.8 g (0.2 moles) of sodium nitrite dissolved in 0.2 parts of water was added dropwise at 5°C under ice-cooling.
After the dropwise addition was completed, the mixture was stirred for 1 hour to react. After the reaction was completed, the reaction solution was filtered, 0.7 g of 42% hydroborofluoric acid was added to the filtrate, and the resulting precipitate was collected by filtration, washed with water, and thoroughly dried. The obtained salt was dissolved in N,N-dimethylformamide 10 to prepare a tetrazonium salt solution to be used in the next reaction. Next, 2-hydroxy-3-(4-methoxy-2
-methylphenylcarbamoyl)-benzo[a]
Carbazole (naphthol AS-SR) 79g (0.2
mole), 60 g of triethanolamine to 10 N,
The tetrazonium salt solution prepared above was added dropwise to the solution dissolved in N-dimethylformamide while cooling with ice, and the mixture was further stirred for 2 hours to react. The resulting crystals were collected by filtration, washed twice with 10 parts of N,N-dimethylformamide and twice with 10 parts of acetone, and dried to yield 73 g (66
%) was obtained. The melting point is 300℃ or higher, the FD-MS spectrum shows an M ⁺ peak at m/z 1099, the infrared spectrum shows a peak of 1 to 1690 cm ^-1 (amide absorption), and elemental analysis shows that C= 74.21
%, N=12.68%, H=4.24% (calculated value is C=
74.30%, N=12.74%, H=4.22%), it is understood that the target substance was synthesized. The bisazo compound of the present invention has excellent photoconductivity, and when producing an electrophotographic photoreceptor using the same, a photosensitive layer in which the bisazo compound of the present invention is dispersed in a binder is formed on a conductive support. It can be manufactured by providing. Another method is to use the bisazo compound of the present invention as a carrier generating substance that takes advantage of its particularly excellent carrier generating ability among its photoconductivity properties, and to use it together with a carrier transporting substance that can effectively act in combination with this. It is also possible to make a so-called functionally separated electrophotographic photoreceptor, such as a laminated type or a dispersed type. Further, the bisazo compound used in the present invention can be used alone or in combination of two or more of the bisazo compounds represented by the above general formula [], or may be used in combination with other bisazo compounds. Various mechanical configurations of electrophotographic photoreceptors are known, and the electrophotographic photoreceptor of the present invention can take any of these forms. Usually, the configuration is as shown in FIGS. 1 to 6. 1 and 3, a carrier generation layer 2 containing the above-mentioned bisazo compound as a main component is provided on a conductive support 1.
and a carrier transport layer 3 containing a carrier transport substance as a main component. As shown in FIGS. 2 and 4, this photosensitive layer 4 may be provided via an intermediate layer 5 provided on a conductive support. When the photosensitive layer 4 has a two-layer structure in this manner, an electrophotographic photoreceptor having the most excellent electrophotographic properties can be obtained. Further, in the present invention, as shown in FIGS. 5 and 6, a photosensitive layer 4 comprising the carrier generating substance 7 dispersed in a layer 6 mainly composed of a carrier transporting substance is provided on the conductive support 1. It may be provided directly or via the intermediate layer 5. When the bisazo compound of the present invention is used as a carrier generating substance, examples of the carrier transporting substance used in combination with the bisazo compound include electron-accepting substances that easily transport electrons such as trinitrofluorenone or tetranitrofluorenone, as well as poly-N-
Polymers having heterocyclic compounds in their side chains such as vinylcarbazole, triazole derivatives, oxadiazole derivatives, imidazole derivatives, birazoline derivatives, polyarylalkane derivatives, phenylenediamine derivatives, hydrazone derivatives, amino-substituted chalcone derivatives , triarylamine derivatives, carebazole derivatives, stilbene derivatives, and other electron-donating substances that easily transport holes, but the carrier transporting substance used in the present invention is not limited to these. The carrier generation layer 2 constituting the photosensitive layer 4 having a two-layer structure is the conductive support 1 or the carrier transport layer 3.
It can be formed directly thereon or, if necessary, with an intermediate layer such as an adhesive layer or a barrier layer provided thereon, for example, 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 is added and mixed as necessary. M-2 A bisazo compound is made into fine particles in a dispersion medium using a ball mill, a homomixer, etc.
A method in which a binder is added as necessary and a mixed and dispersed dispersion is applied. Solvents or dispersion media used for forming the carrier generation layer include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N,N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, benzene, and toluene. , xylene, chloroform,
Examples include 1,2-dichloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and the like. When using a binder in the carrier generation layer or carrier transport layer, any binder can be used, but it is preferable to use a film-forming polymer that is hydrophobic, has a high dielectric constant, and is electrically insulating. . Examples of such high molecular weight polymers include, but are not limited to, the following. P-1 Polycarbonate P-2 Polyester P-3 Methacrylic resin 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 These binders can be used alone or in a mixture of two or more. The thickness of the carrier generation layer 2 thus formed is preferably 0.01 μm to 20 μm, more preferably 0.05 μm to 5 μm. Further, when the carrier generation layer or the photosensitive layer is a dispersed type, the particle size of the azo compound is preferably 5 μm or less, more preferably 1 μm or less. The conductive support used in the electrophotographic photoreceptor of the present invention is a metal plate including an alloy, a metal drum or a conductive polymer, a conductive compound such as indium oxide, aluminum including an alloy, palladium, gold, etc. Examples include paper, plastic film, etc. that have been made conductive by coating, vapor depositing, or laminating a thin metal layer. As an intermediate layer such as an adhesive layer or a barrier layer, in addition to the polymer used as the binder, an organic polymer material such as polyvinyl alcohol, ethyl cellulose, or carboxymethyl cellulose, or aluminum oxide is used. The electrophotographic photoreceptor of the present invention has the above-mentioned structure, and 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. Hereinafter, the present invention will be specifically explained in Examples,
This does not limit the embodiments of the present invention. (Examples) Example 1 32 g of Exemplified Compound A and 2 g of polycarbonate resin "Panlite L-1250" (manufactured by Teijin Chemicals) were added to 110 ml of 1,2-dichloroethane, and dispersed in a ball mill for 12 hours. This dispersion was applied to a polyester film on which aluminum was vapor-deposited so that the dry film thickness was 1 μm to form a carrier generation layer.
-(1-Ethyl-4-carbazolyl)methylideneamino-1,2,3,4-tetrahydroquinoline (Structural formula K-(1) below) 6g and polycarbonate resin "Panlite L-1250" 10g and 1,2- The film thickness after drying the solution dissolved in 110ml of dichloroethane is
A carrier transport layer was formed by coating to a thickness of 15 μm, and an electrophotographic photoreceptor of the present invention was prepared. The photoreceptor obtained as described above was subjected to the following temporal evaluation using an electrostatic paper tester model SP-428 manufactured by Kawaguchi Electric Seisakusho Co., Ltd. After charging with a charging voltage of -6KV for 5 seconds, leave in the dark for 5 seconds, then irradiate with halogen lamp light so that the illuminance on the photoreceptor surface is 35 lux, and calculate the exposure amount required to attenuate the surface potential by half. (Half-reduced exposure amount) E1/2 was determined. Also
The surface potential (residual potential) V _R after exposure with an exposure amount of 30 lux·sec was determined. Furthermore, similar measurements were repeated 100 times. The results are shown in Table 1.

[Table] Comparative Example 1 The following bisazo compound G was used as a carrier generating substance.
A comparative photoreceptor was prepared in the same manner as in Example 1 except that -(1) was used. Regarding this electrophotographic photoreceptor for comparison, Example 1
When measurements were carried out in the same manner as above, the results shown in Table 2 were obtained.

[Table] As is clear from the above results, the electrophotographic photoreceptor of the present invention is extremely superior in sensitivity, residual potential, and repetition stability compared to the comparative electrophotographic photoreceptor. Example 2-4 Exemplary compounds A-(5) and A as carrier generating substances
-(10) and A-(39) were used as carrier transport substances, 1-(1-ethyl-4-carbazolyl)methylideneamino-indoline (compound K-(2) below) and 4-methoxy-4, respectively. '-(4-methoxy)styryl-triphenylamine (compound K-(3) below), and 4-methyl-4'-(4-chloro)-
Styryl-triphenylamine (compound K- below)
(4)), and in the same manner as in Example 1, an electrophotographic photoreceptor of the present invention was prepared, and the same measurements were performed, and the results shown in Table 3 were obtained.

[Table] Example 5 A vinyl chloride-vinyl acetate-maleic anhydride copolymer "Eslec MF-10" (manufactured by Sekisui Chemical Co., Ltd.) was placed on a conductive support made of aluminum foil laminated on a polyester film. thickness
A 0.05 μm intermediate layer is provided, and exemplified compound A is placed on top of the intermediate layer.
2 g of -(42) was mixed with 110 ml of 1,2-dichloroethane and dispersed in a ball mill for 24 hours. The dispersion was applied to a dry film thickness of 0.5 μm to form a carrier generation layer. On this carrier generation layer, 6 g of 4-methyl-triphenylamine and methacrylic resin "Acrypet" (manufactured by Mitsubishi Rayon Co., Ltd.) are added.
An electrophotographic photoreceptor of the present invention was prepared by dissolving 10 g of 1,2-dichloroethane in 70 ml of 1,2-dichloroethane and applying the solution to a dry film thickness of 10 μm to form a carrier transport layer. When the same measurements as in Example 1 were carried out on this electrophotographic photoreceptor, the first measurement was E1/2.
= 2.1lux・sec, V _R = 0V were obtained. Example 6 On the conductive support provided with the intermediate layer used in Example 5, a 1% ethylenediamine solution of Exemplified Compound A-(48) was applied to a dry film thickness of 0.3 μm, and a carrier was applied. A generation layer was formed. Then, 1-phenyl-3-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline (compound K-(5) below) 6g of polyester resin "Bylon 200" (manufactured by Toyobo Co., Ltd.) 10g and 70ml of 1,2-dichloroethane
The electrophotographic photoreceptor of the present invention was prepared by dissolving this solution into a carrier transport layer and applying this solution to a dry film thickness of 12 μm. The same measurements as in Example 1 were performed on this electrophotographic photoreceptor, and the results shown in Table 4 were obtained. Comparative Example 2 A comparative electrophotographic photoreceptor was prepared in the same manner as in Example 6 except that exemplified compound A-(48) was replaced with bisazo compound G-(2) represented by the following structural formula. The same measurements as in Example 1 were performed on this electrophotographic photoreceptor, and the results are shown in Table 4.

[Table] Example 7 A carrier generation layer was formed in the same manner as in Example 5 except that Exemplified Compound A-(42) was replaced with Exemplified Compound A-(2). On top of this, 6 g of 3-(p-methoxystyryl)-9-(p-methoxyphenyl)carbazole (compound K-(6)) and 10 g of polycarbonate "Panlite L-1250" (manufactured by Teijin Chemicals), A carrier transport layer was formed by coating a solution dissolved in 70 ml of 1,2-dichloroethane so that the film thickness after drying was 10 μm, thereby producing an electrophotographic photoreceptor of the present invention. Regarding this electrophotographic photoreceptor, measurements were carried out in the same manner as in Example 1. E1/2=2.5lux・
sec and V _R =0V. Example 8 An intermediate layer with a thickness of 0.05 μm made of vinyl chloride-vinyl acetate-maleic anhydride copolymer “Eslec MF-10” (manufactured by Sekisui Chemical Co., Ltd.) was provided on the surface of an aluminum drum with a diameter of 100 mm, and then Add 4 g of Exemplified Compound A-(46) to 400 ml of 1,2-dichloroethane.
The dispersion liquid was mixed with the following and dispersed for 24 hours using a ball mill dispersion machine, and the 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 this, 30 g of p-(N,N-diethylamino)benzaldehyde-1,1-diphenylhydrazone (compound K-(6) below) and 50 g of polycarbonate resin "Corpilon S-1000" (manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 1,2-dichloroethane A carrier transport layer was formed by dissolving the solution in 400 ml and coating it to a film thickness of 13 μm after drying, thereby producing a drum-shaped electrophotographic photoreceptor. The photoreceptor thus created was attached to a modified electrophotographic copying machine "U-Bix V2" (manufactured by Konishiroku Photo Industry Co., Ltd.), and when the image was copied, the contrast was high and the image was clear and faithful to the original. A duplicate image was obtained. Moreover, this did not change even after repeating this 10,000 times. Comparative Example 3 In Example 8, Exemplary Compound A-(46) was converted into a trisazo compound (G-
A drum-shaped comparative photoreceptor was prepared in the same manner as in Example 8, except that (3)) was replaced, and copied images were evaluated in the same manner as in Example 8. Only images with a lot of fog were obtained. Ta. Also, as copying is repeated, the contrast of the copied image decreases, and
After repeating this process several times, almost no duplicate images were obtained. Example 9 A layer of vinyl chloride-vinyl acetate-maleic anhydride copolymer "Eslec MF-10" (manufactured by Sekisui Chemical Co., Ltd.) was placed on a conductive support made of aluminum foil laminated on a polyester film.
A 0.05 μm intermediate layer is provided, and exemplified compound A is placed on top of the intermediate layer.
- Add 5 g of (35) and 3.3 g of polycarbonate resin "Panlite L-1250" (manufactured by Teijin Chemicals) to 100 ml of dichloromethane, and disperse the dispersion in a ball mill for 24 hours so that the film thickness when dried is 10 μm. An electrophotographic photoreceptor was prepared. The photoconductor obtained in the above manner is charged with a +
E1/2 and E1/2 in the same manner as in Example 1 except that 6KV was used.
_VR was measured. The first result is E1/2=
It was 3.5lux·sec and V _R =+10V. Example 10 4-Methoxy-4'- as a carrier transport layer on a polyester film deposited with aluminum
6 g of styryl-triphenylamine and 10 g of polyester resin "Vylon 200" (manufactured by Toyo Boseki Co., Ltd.) were dissolved in 70 ml of 1,2-dichloroethane, and this solution was applied so that the film thickness after drying was 10 μm. Next, 1 g of exemplified compound A-(9) and A-
(40) was mixed with 110 ml of 1,2-dichloroethane and dispersed in a ball mill for 24 hours. The dispersion was applied to a dry film thickness of 0.5 μm to form a carrier generation layer, and the electrophotographic photosensitive material of the present invention formed a body. When the thus obtained photoreceptor was evaluated in the same manner as in Example 9, it was found that E1/2 = 3.3 lux·sec and V _R = +15V. Example 11 A 2% ethylenediamine solution of Exemplified Compound A-(41) was applied onto a polyester film laminated with aluminum to a dry film thickness of 0.5 μm to form a carrier generation layer. Furthermore, 1-[4-(N,
N-diethylamino)-benzylidene]-amino-
1,2,3,4 tetrahydroquinoline (compound K-(7) below), 4,4′-dimethyl-4″-(4-methoxy)styryl-triphenylamine (compound K-(8) below), or Separately about 10 g each of 4,4'-dimethyl-triphenylamine (compound K-(9) below) and polycarbonate. Resin (manufactured by Teijin Chemicals, Panlite L-1250) 14g
A solution prepared by dissolving 1,2-dichloroethane in 140 ml was coated so as to have a dry film thickness of 12 μm, and dried to obtain photoreceptors containing three different carrier transport substances. These three types of photoreceptors are manufactured by Kawaguchi Electric Manufacturing Co., Ltd.
The following specific evaluations were performed using an electrostatic paper tester model SP-428 manufactured by Co., Ltd. Charge the material with a charging voltage of -6KV for 5 seconds, leave it in the dark for 5 seconds, and then irradiate it with barogen light so that the surface potential of the material is 35 lux. The exposure amount (E1/2) was measured. In addition, the surface potential (residual potential) V _R after exposure with an exposure amount of 30 lux·sec was measured. As shown in Table 5, the results were good in combination with any carrier transport substance.

[Table] Comparative Example 4 A comparative photoreceptor was prepared in the same manner as in Example 11, except that the exemplified compound A-(41) was replaced with the following bisazo compound (G-(4)), and the characteristics were evaluated. As a result, As shown in Table 6, the results varied depending on the carrier transport substance.

[Table] Example 12 On the conductive support provided with the intermediate layer used in Example 5, 2 g of exemplified compound A-(9)) and 100 ml of 1,2-dichloroethane were well dispersed and mixed, and after drying, A carrier generation layer was created by applying the film to a thickness of 0.3 μm. 4- is then added thereon as a carrier transport material.
6 g of methyl-4'-styryl-triphenylamine (compound K-(10) below) and polycarbonate "Panlite L-1250" (manufactured by Teijin Chemicals) A carrier transport layer was formed by dissolving 10 g of 1,2-dichloroethane in 90 g of 1,2-dichloroethane and applying the solution to a dry film thickness of 10 μm, thereby producing an electrophotographic photoreceptor of the present invention. The electrophotographic properties of this electrophotographic photoreceptor at room temperatures of 25° C. and 60° C. were measured in the same manner as in Example 7. The results are shown in Table 7.

[Table] As is clear from the above results, the electrophotographic photoreceptor of the present invention has good sensitivity and residual potential characteristics even at high temperatures, and is stable against heat. Example 13 2 g of Exemplified Compound A-(40) and 110 ml of 1,2-dichloroethane were well dispersed and mixed on the conductive support provided with the intermediate layer used in Example 5, and the film thickness after drying was 0.3 μm. A carrier generation layer was created by applying the following coating. This carrier generation layer was irradiated with UV light of 1500 cd/cm ² for 10 minutes by placing an ultra-high pressure mercury lamp (manufactured by Tokyo Shibaura Electric Co., Ltd.) 30 cm away. Next, 1-(1-phenyl-
4-carbazolyl)methylideneamino-1,2,
3,4-tetrahydroquinoline (compound K- below)
(11)) 7g and polycarbonate [Panlite L-
1250] (manufactured by Teijin Chemicals) 10g, 1,2-dichloroethane A carrier transport layer was formed by applying a solution dissolved in 90 g to a dry film thickness of 12 μm, thereby producing an electrophotographic photoreceptor of the present invention. The same measurements as in Example 5 were performed on this electrophotographic photoreceptor. The results are shown in Table 8. Example 14 An electrophotographic photoreceptor of the present invention was prepared in the same manner as in Example 13, except that UV light was not irradiated after the carrier generation layer was formed, and the same measurements as in Example and 5 were carried out. The results are shown in Table 8.

[Table] As is clear from the above results, the electrophotographic photoreceptor of the present invention has excellent sensitivity and residual potential characteristics against UV light irradiation, has small fluctuations in acceptance potential, and is stable against light. I can understand. Comparative Example 5 Compound A-(40) was mixed with the following bisazo compound (G
-(5)) Same as Example 13 and Example 14 except that An electrophotographic photoreceptor was prepared in the same manner, and the same measurements as in Example 5 were performed. The results are shown in Table 9.

[Table] As is clear from the above results, the sensitivity and residual potential characteristics of the electrophotographic photoreceptor prepared using the above compound deteriorate when irradiated with UV light, and the amount of variation in acceptance potential is large. Example 14 In Example 5, Exemplified Compound A-(42) was replaced with A-
A drum-shaped electrophotographic photoreceptor was produced in the same manner except that (1) was replaced. The spectral sensitivity of this photoreceptor at 790 nm was 1.12 μJ/cm ² (half exposure amount). A practical test was carried out on the photoreceptor of the present invention using a practical machine equipped with a semiconductor laser (790 nm) with a laser beam intensity of 0.85 mW on the surface of the photoreceptor. After the surface of the photoreceptor was charged to -6 KV, it was exposed to laser light and reverse development was performed at a bias voltage of -250 V. A good image without fogging was obtained. Comparative Example 6 A comparative photoreceptor was obtained in the same manner as in Example 14, except that the following comparative bisazo compound was used in place of Exemplified Compound A-35. The spectral sensitivity of this photoreceptor at 790nm is
It was 12.1 μJ/cm ² (half exposure amount). Using this comparative photoreceptor, an actual photographic test using a semiconductor laser was conducted in the same manner as in Example 14, but there was a lot of fog and no good images could be obtained. As is clear from the results of the above Examples and Comparative Examples, the electrophotographic photoreceptor of the present invention has better characteristics such as stability, sensitivity, durability, and combination with a wide range of carrier transport materials than the comparative electrophotographic photoreceptor. It is extremely excellent.

[Brief explanation of the drawing]

1 to 6 are sectional views showing examples of the mechanical structure of the electrophotographic photoreceptor of the present invention, and 1 to 7 in the figures represent the following, respectively. 1... Conductive support, 2... Carrier generation layer,
3... Carrier transport layer, 4... Photosensitive layer, 5... Intermediate layer, 6... Layer containing a carrier transport substance, 7
...Carrier generating substance.

Claims (1)

[Scope of Claims] 1. An electrophotographic photoreceptor comprising a photosensitive layer containing a bisazo compound represented by the following general formula [] on a conductive support. General formula [] [Wherein, Y ₁ and Y ₂ are a group selected from a hydrogen atom, a halogen atom, a cyano group, an alkyl group, or an alkoxy group, A: [Formula] [Formula] [Formula] or [Formula], and Z: Substituted/unsubstituted aromatic carbocycle or atomic group necessary to constitute substituted/unsubstituted aromatic carbocycle, Q: substituted/unsubstituted carbamoyl group or substituted/unsubstituted aromatic carbocycle;
Unsubstituted sulfamoyl group, R ₁ : hydrogen atom, substituted/unsubstituted alkyl group, substituted/unsubstituted amino group, substituted/unsubstituted carbamoyl group, carboxy group and its ester group, or cyano group, A′: Substituted/unsubstituted aryl group, R ₂ and R ₃ represent substituted/unsubstituted alkyl group, substituted/unsubstituted aralkyl group, or substituted/unsubstituted aryl group. 2. The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer contains a carrier transporting substance and a carrier generating substance, and the carrier generating substance is a bisazo compound represented by the general formula [].