JPH06100839B2 - Electrophotographic photoreceptor - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electrophotographic photosensitive member that is preferably used in an image forming apparatus such as a copying machine.

(Prior Art) In recent years, as an electrophotographic photosensitive member having a photosensitive layer formed on a conductive substrate, an organic photosensitive member is used which has good processability and is advantageous in terms of manufacturing cost and has a large degree of freedom in functional design. Has been done. The above-mentioned organic photoreceptor has a photosensitive layer in which a charge generating function and a charge transporting function are separated by a charge generating material that generates a charge by light irradiation and a charge transporting material that transports the generated charge, thereby improving the sensitivity. There is known a function-separated type electrophotographic photoreceptor for achieving the above-mentioned purpose. The photosensitive layer of the function-separated electrophotographic photoreceptor is a laminated photoreceptor in which a charge generation layer containing at least a charge generation material and a charge transport layer containing a charge transport material and a binder resin are laminated. In addition, various types of single-layer type photoreceptors in which a charge generating material and a charge transporting material are dispersed in a binder resin have been proposed.

Since the laminated photoreceptor has various functions separated by the charge generation layer and the charge transport layer, it has an advantage that it has high sensitivity and a wide selection range of photosensitive materials, unlike the single-layer photoreceptor.

By the way, since many charge transport materials are of positive charge transport type and have a durable surface, a charge generation layer is provided on a conductive substrate, and a charge transport layer is further provided on the charge generation layer. It is common to have a body structure. However, in such a negative charging laminated photoreceptor, ozone is generated in the atmosphere at the time of negative charging to cause deterioration of the photoreceptor and pollution of the copying environment, and at the time of development, a positive charging toner which is difficult to manufacture is required. There is a problem such as

On the other hand, the above-mentioned single-layer type photoreceptor can be positively charged, and a negatively chargeable toner can be used as a toner for developing an electrostatic latent image on the photoreceptor. This is advantageous because, in general, it is easy to obtain a toner that is negatively charged, so that the selection range of toner materials is wide and various toner materials can be used. However, since electrons and holes are moved in one layer, one of them becomes a trap and the residual potential tends to increase. In addition, there is a problem that the combination of the charge generating material and the charge transporting material greatly affects the electrophotographic characteristics such as charging characteristics, sensitivity and residual potential.

Therefore, in view of the above problems, a diamine derivative having a small electric field strength dependency on drift mobility and a perylene-based compound are combined to obtain a positive charging single layer having excellent charging characteristics, sensitivity, electrophotographic characteristics such as residual potential, and the like. Type electrophotographic photoreceptor (Japanese Patent Application No. 62-277158 (see Japanese Patent Publication No. 5-20742))
Was proposed first.

(Problems to be Solved by the Invention) However, the photoconductor disclosed in Japanese Patent Application No. 62-277158 previously proposed has excellent electrophotographic properties such as charging property, sensitivity, residual potential, etc. The inventors of the present invention have conducted extensive studies to provide a photoreceptor having excellent surface potential stability even after repeating the above procedure. As a result, the photoreceptor of the present invention has been completed.

Therefore, it is an object of the present invention to provide a positively chargeable single-layer type electrophotographic photosensitive member which is excellent not only in electrophotographic characteristics such as charging characteristics, sensitivity and residual potential but also in repeated stability.

(Means and Actions for Solving Problems) Accordingly, in the present invention, the following general formula [1] is used as a charge generating material in the binder resin. (Wherein R ¹ , R ² , R ³ , and R ⁴ represent an alkyl group), and the above-mentioned perylene compound 10
0.62 to 1.88 parts by weight of oxotitanyl phthalocyanine with respect to 0 parts by weight, and the following general formula [I
I] And a hydrazone-based compound represented by the following general formula [III], a fluorene-based compound represented by the following general formula [IV], and m- represented by the following general formula [V]. Phenylenediamine compounds (In the formula, R ⁵ represents a hydrogen atom or an alkyl group) (In the formula, R ⁶ , R ⁷ , R ⁸ and R ⁹ represent a hydrogen atom or an alkyl group) (In the formula, R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , and R ^{14 each} represent an alkyl group, an alkoxyl group, or a halogen atom. All the substituents may be the same or different from each other.) A photosensitive layer containing at least one selected from the group consisting of The above object was achieved by constructing the body.

As a result of earnest studies by the present inventors, the perylene-based compound represented by the general formula [I] as a charge generation material, oxotitanyl phthalocyanine, and the general formula [II] as a charge transport material.
In a photoreceptor having a single-layer type photosensitive layer containing a diamine derivative represented by a binder resin, a hydrazone compound represented by the general formula [III], the general formula [I
V] a fluorene compound represented by the general formula [V]
It has been found that a stable surface potential can be maintained even when the copying process is repeated by selecting and mixing at least one kind from the group consisting of m-phenylenediamine compounds represented by

(Preferable Embodiments of the Invention) The perylene-based compound as the charge generating material used in the present invention is represented by the general formula [1], and R ¹ , R ² , R ³ and R in the formula
Examples of the alkyl group among ⁴ include alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl and hexyl groups.

Specifically, N, N'-di (3,5-dimethylphenyl) perylene-3,4,9,10-tetracarboxydiimide, N, N'-
Di (3-methyl-5-ethylphenyl) perylene-3,4,
9,10-Tetracarboxydiimide, N, N'-di (3,5-diethylphenyl) perylene-3,4,9,10-tetracarboxydiimide, N, N'-di (3,5-dipropylphenyl ) Perylene-3,4,9,10-tetracarboxydiimide, N, N '
-Di (3,5-diisopropylphenyl) perylene-3,4,
9,10-Tetracarboxydiimide, N, N'-di (3-methyl-5-isopropylphenyl) perylene-3,4,9,10
-Tetracarboxydiimide, N, N'-di (3,5-dibutylphenyl) perylene-3,4,9,10-tetracarboxydiimide, N, N'-di (3,5-di-tert-butylphenyl )
Perylene-3,4,9,10-tetracarboxydiimide, N,
N'-di (3,5-dipentylphenyl) perylene-3,4,9,
10-tetracarboxydiimide, N, N'-di (3,5-dihexylphenyl) perylene-3,4,9,10-tetracarboxydiimide and the like are exemplified, but among them, N, N'-di (3 ,Five
-Dimethylphenyl) perylene-3,4,9,10-tetracarboxydiimide is preferred.

The oxotitanyl phthalocyanine used as the charge generation material in the present invention has, for example, the following general formula [V] having various crystal types such as α type, β type, γ type, δ type and ε type.
I] (In the formula, X represents a halogen atom, and n represents 0 or an integer of 1 or more), and oxotitanyl phthalocyanine is exemplified. Among them, the halogen atom in the general formula [VI] is bromine or Chlorine, n = 0,
Bragg angle (2θ ± 0.2 in X-ray diffraction spectrum
°) is 6.9 °, 9.6 °, 15.6 °, 17.6 °, 21.9 °, 23.6
Α-type oxotitanyl phthalocyanine which shows strong diffraction peaks at °, 24.7 ° and 28.0 ° and has the largest diffraction peak at 6.9 ° among the Bragg angles is preferable.

Since the perylene-based compound does not have spectral sensitivity on the long wavelength side, the spectral sensitivity region is shifted to the long-wavelength side by adding 0.62 to 1.88 parts by weight to 100 parts by weight of the perylene-based compound of the oxotitanyl phthalocyanine. , The sensitivity of the photoconductor becomes higher when combined with a halogen lamp having a large red spectral energy. However, only by adding 0.62 parts by weight or less of oxotitanyl phthalocyanine to 100 parts by weight of the perylene compound, the sensitizing effect on the long wavelength side does not occur. On the contrary, if 1.88 parts by weight or more of oxotitanyl phthalocyanine is added to 100 parts by weight of perylene-based compound, the spectral sensitivity on the long wavelength side is increased and the reproducibility of the red original document is deteriorated.

Examples of the diamine derivative as the charge transport material used in the present invention include 3,3′-dimethyl-N, N, N ′, N′-tetrakis-4-methylphenyl (represented by the general formula [II]. 1,1'-biphenyl) -4,4'-diamine is used.

As the binder resin used in the present invention, various ones, for example, a styrene polymer, an acrylic polymer, a styrene-acrylic polymer, polyethylene, an ethylene-vinyl acetate copolymer, a chlorinated polyethylene, a polypropylene. ,
Olefin-based polymers such as ionomer, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyester,
Alkyd resin, polyamide, polyurethane, epoxy resin, polycarbonate, polyarylate, polysulfone, diallyl phthalate, silicone resin, ketone resin, polyvinyl butyral resin, polyether resin, phenol resin, and photocurable resin such as epoxy acrylate. Polymers can be used, but the sensitivity of the photoconductor is improved, the abrasion resistance and repeatability of the photoconductor are excellent, and the selection range of the solvent that dissolves the binder resin is wide (4,4 ').
-Cyclohexylidenediphenyl) carbonate is preferred. When poly (4,4′-cyclohexylidenediphenyl) carbonate is used, tetrahydrofuran is different from bisphenol A type polycarbonate, which has conventionally been able to use only chlorine-based solvents such as dichloromethane and monochlorobenzene from the viewpoint of solution stability. Since a solvent such as methyl ethyl ketone can also be used, it is preferable in terms of safety and hygiene and is easy to handle. Among the above poly (4,4′-cyclohexylidenediphenyl) carbonates, the molecular weight is 15,000 to 25,000 and the glass transition point is 58 ° C.
Something is preferable.

The use ratio of the perylene compound, the diamine derivative and the binder resin is not particularly limited and can be appropriately selected according to the desired characteristics of the electrophotographic photoreceptor, etc., but the binder resin is 100 parts by weight. On the other hand, the perylene compound is 2 to 20 parts by weight, preferably 3 to 15 parts by weight, the diamine derivative 40 to
200 parts by weight, preferably 50-100 parts by weight are used. When the amount of the perylene compound and the diamine derivative used is less than the above-mentioned amount, not only the sensitivity of the photoconductor is insufficient but also the residual potential becomes large. On the other hand, if it exceeds the above range, the abrasion resistance of the photoconductor becomes insufficient.

Furthermore, in the single-layer type photoreceptor containing the perylene compound and the diamine derivative in the binder resin, the hydrazone compound represented by the general formula [III], the general formula [I
V] a fluorene compound represented by the general formula [V]
One of the m-phenylenediamine compounds represented by the formula (1) is selected and mixed, or the hydrazone represented by the general formula [III] is added to the fluorene compound represented by the general formula [IV]. By combining two types of compounds, or by selecting and mixing two kinds of m-phenylenediamine type compounds represented by the general formula [V], it is possible to prevent a decrease in surface potential during repetition of the copying process and stabilize. The surface potential can be maintained.

The alkyl group in the above general formulas [III], [IV] and [V] is an alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl and hexyl groups. Is exemplified.
Examples of the alkoxyl group in the general formula [V] include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, tert-butoxy, pentyloxy, hexyloxy groups and the like. Further, the halogen atom in the general formula [V] is fluorine,
Included are chlorine, bromine and iodine atoms.

Examples of the hydrazone compound represented by the general formula [III] include 3-carbazolylaldehyde N, N-diphenylhydrazone, N-methyl-3-carbazolylaldehyde N,
N-diphenylhydrazone, N-ethyl-3-carbazolylaldehyde N, N-diphenylhydrazone, N-propyl-3-carbazolylaldehyde N, N-diphenylhydrazone, N-isopropyl-3-carbazolylaldehyde N , N-diphenylhydrazone, N-butyl-3-carbazolylaldehyde N, N-diphenylhydrazone, N
-Isobutyl-3-carbazolylaldehyde N, N-diphenylhydrazone, N-tert-butyl-3-carbazolylaldehyde N, N-diphenylhydrazone, N-pentyl-3-carbazolylaldehyde N, N-diphenyl Hydrazone, N-hexyl-3-carbazolyl aldehyde N,
Examples of N-diphenylhydrazone and the like, among them,
N-ethyl-3-carbazolyl aldehyde N, N-diphenylhydrazone is preferred.

Examples of the fluorene compound represented by the general formula [IV] include 9-carbazolyliminofluorene, 9- (3-methylcarbazolylimino) fluorene, 9- (3,6-dimethylcarbazolylimino). Fluorene, 9- (3,6-
Diethylcarbazolylimino) fluorene, 9- (3-
Ethyl-6-methylcarbazolylimino) fluorene,
9- (3,6-dipropylcarbazolylimino) fluorene, 9- (3,6-diisopropylcarbazolylimino)
Fluorene, 9- (3,6-dibutylcarbazolylimino) fluorene, 9- (3,6-diisobutylcarbazolylimino) fluorene, 9- (3,6-di-tert-butylcarbazolylimino) fluorene , 9- (3,6-dipentylcarbazolylimino) fluorene, 9- (3,6-dihexylcarbazolylimino) fluorene, 9- (3,6
-Dimethylcarbazolylimino) -3-methylfluorene, 9- (3,6-dimethylcarbazolylimino) -3,6-
Examples include dimethylfluorene, 9- (3,6-dimethylcarbazolylimino) -3,6-diethylfluorene, and 9- (3,6-dimethylcarbazolylimino) -3-ethylfluorene, but among them, 9-carbazolyliminofluorene is preferred.

Examples of the m-phenylenediamine compound represented by the general formula [V] include N, N, N ', N'-tetraphenyl-1,3-
Phenylenediamine, N, N, N ', N'-tetrakis (3-
Tolyl) -1,3-phenylenediamine, N, N, N ', N'-tetraphenyl-3,5-tolylenediamine, N, N, N', N'-
Tetrakis (3-tolyl) -3,5-tolylenediamine,
N, N, N ', N'-tetrakis (4-tolyl) -1,3-phenylenediamine, N, N, N', N'-tetrakis (4-tolyl) -3,5-tolylenediamine, N , N, N ', N'-Tetrakis (3-ethylphenyl) -1,3-phenylenediamine, N, N, N', N'-Tetrakis (4-propylphenyl) -1,3-phenylenediamine, N , N, N ′, N′-tetraphenyl-5-methoxy-1,3-phenylenediamine,
N, N, -bis (3-tolyl) -N ', N'-diphenyl-1,
3-phenylenediamine, N, N'-bis (4-tolyl)-
N, N'-diphenyl-1,3-phenylenediamine, N, N '
-Bis (4-tolyl) -N, N'-bis (3-tolyl)-
1,3-phenylenediamine, N, N'-bis (4-tolyl)
-N, N'-bis (3-tolyl) -3,5-tolylenediamine, N, N'-bis (4-ethylphenyl) -N, N'-bis (3-ethylphenyl) -1,3 -Phenylenediamine,
N, N'-bis (4-ethylphenyl) -N, N'-bis (3
-Ethylphenyl) -3,5-tolylenediamine, N, N,
N ', N'-tetrakis (2,4,6-trimethylphenyl)-
1,3-phenylenediamine, N, N, N ', N'-tetrakis (2,4,6-trimethylphenyl) -3,5-tolylenediamine, N, N, N', N'-tetrakis (3 , 5-Dimethyl) -1,3
-Phenylenediamine, N, N, N ', N'-tetrakis (3,5
-Dimethyl) -3,5-tolylenediamine, N, N, N ', N'-
Tetrakis (3,5-diethyl) -1,3-phenylenediamine, N, N, N ', N'-tetrakis (3,5-dimethyl) -3,5
-Tolylenediamine, N, N, N ', N'-tetrakis (3-
Chlorophenyl) -1,3-phenylenediamine, N, N,
N ', N'-tetrakis (3-bromophenyl) -1,3-phenylenediamine, N, N, N', N'-tetrakis (3-iodophenyl) -1,3-phenylenediamine, N, N, N ′,
N'-tetrakis (3-fluorophenyl) -1,3-phenylenediamine and the like are exemplified, but among them, the interaction between molecules becomes small due to poor symmetry of molecules, and conversely with resin. Since it has a characteristic that it is extremely difficult to crystallize and can be sufficiently dissolved in a resin due to an increase in the interaction of R, R ¹⁰ , R ¹¹ , R ¹³ and R ¹⁴ in the above general formula [V] are meta-positioned with respect to the nitrogen atom. A compound that is used as a substituting group, or
A compound in which R ¹⁰ and R ¹⁴ are substituted at the para position with respect to the nitrogen atom and R ¹¹ and R ¹³ are substituted at the meta position with respect to the nitrogen atom is preferable. Specifically, N, N, N ', N'-tetrakis (3-tolyl) -1,3-phenylenediamine, N, N'-bis (4-tolyl) -N, N'-bis (3- Tolyl) -1,3-phenylenediamine.

Incidentally, each of the above compounds can be used in an appropriate amount depending on the characteristics of the photoreceptor, but when a hydrazone compound is used among the above compounds, a diamine compound and a hydrazone compound as a charge transport material are used. And 95: 5 to 90: 1
It is preferably contained in the photosensitive layer in a weight ratio of 0.

When a fluorene compound is used among the above compounds, it is preferable that the diamine compound and the fluorene compound as the charge transport material are contained in the photosensitive layer in a weight ratio of 90:10 to 80:20. .

In the case of using the m-phenylenediamine compound among the above compounds, the ratio of the diamine compound and the m-phenylenediamine compound as the charge transport material is 75:25.
It is preferable that the photosensitive layer contains it in a weight ratio of from 25 to 75:75, particularly from 70:30 to 50:50.

That is, if the photosensitive layer contains each of the above compounds in a ratio smaller than the above weight ratio, the repeating characteristics are not sufficient, and if the above compounds are contained in a ratio exceeding the above weight ratio, the repeating characteristics become high, but the sensitivity and the like are sufficient. It will not be.

In addition, when an antioxidant is used in combination, it is possible to preferably prevent deterioration of a charge transporting material or the like having a structure that is affected by oxidation and is inexpensive, due to oxidation.

As the above-mentioned antioxidant, 2,6-di-tert-butyl-p
-Cresol, triethylene glycol-bis [3-
(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], penta Erythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-di-tert-butyl-4-] Hydroxyphenyl) propionate], 2,2-thiobis (4-
Methyl-6-tert-butylphenol), N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,
Examples thereof include phenolic antioxidants such as 4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, and among them, 2,6-di-tert-butyl-p -Cresol is preferred.

The photoconductor of the present invention can be obtained by preparing a coating solution containing each of the above-mentioned components, coating the coating solution on a conductive substrate, and drying.

The conductive substrate may be in the form of a sheet or a drum having conductivity, various materials having conductivity,
For example, aluminum whose surface is anodized or untreated, aluminum alloy, copper, tin, platinum, gold,
A simple metal such as silver, vanadium, molybdenum, chromium, cadmium, titanium, nickel, palladium, indium, stainless steel, or brass, or a plastic material on which a layer of the above metal, indium oxide, tin oxide or the like is formed by a method such as vapor deposition. Examples thereof include glass and the like, but among them, aluminum subjected to anodic oxidation by the sulfuric acid alumite method and sealed with nickel acetate is preferable.

In addition, the conductive substrate may be subjected to a surface treatment with a surface treatment agent such as a silane coupling agent or a titanium coupling agent, if necessary, to enhance the adhesion to the photosensitive layer.

In adjusting the coating solution, an appropriate organic solvent is used according to the type of the binder resin used, and examples of the organic solvent include alcohols such as methanol, ethanol, propanol, isopropanol and butanol. , Aliphatic hydrocarbons such as n-hexane, octane and cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, carbon tetrachloride and chlorobenzene, tetrahydrofuran, ethylene glycol dimethyl ether Various solvents such as ethers such as ethylene glycol diethyl ether, ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and methyl acetate are illustrated, and one solvent or a mixture of two or more solvents is used. Further, when adjusting each of the above-mentioned coating solutions, in order to improve dispersibility, coatability, etc., silicone oil such as polydimethylsiloxane, a leveling agent such as a surfactant, or terphenyl, halonaphthoquinones, acenaphthylene, etc. Various additives such as conventionally known sensitizers may be used in combination.

Each of the above-mentioned coating liquids and the like can be prepared by using a conventionally used mixing / dispersing method, for example, a paint shaker, a mixer, a ball mill, a sand mill, an attritor, an ultrasonic disperser, or the like, and the obtained dispersion liquid or the like is coated. On the occasion,
Conventional coating methods such as dip coating, spray coating, spin coating,
Roller coating, blade coating, curtain coating, bar coating and the like are used.

The single-layer type photosensitive layer of the electrophotographic photosensitive member of the present invention may have an appropriate thickness, but is 15 to 30 μm, and particularly 18 to 27 μm.
Those having a thickness of are preferable.

(Example) Below, this invention is demonstrated in detail based on an Example.

Example 1 100 parts by weight of poly- (4,4′-cyclohexylidenediphenyl) carbonate (trade name Polycarbonate Z, manufactured by Mitsubishi Gas Chemical Co., Inc.), N, N′-di (3,5-dimethylphenyl)
8 parts by weight of perylene-3,4,9,10-tetracarboxydiimito, 0.1 part by weight of α-type oxotitanyl phthalocyanine, 3,
95% by weight of 3'-dimethyl-N, N, N ', N'-tetrakis-4-methylphenyl (1,1'-biphenyl) -4,4'-diamine, N-ethyl-3-carbazolylaldehyde N, N-
5 parts by weight of diphenylhydrazone, 5 parts by weight of antioxidant (Kawaguchi Chemical Co., Ltd., trade name Antage BHT), 0.01 parts by weight of polydimethylsiloxane (Shin-Etsu Chemical Co., Ltd.) and a predetermined amount of tetrahydrofuran are mixed and dispersed by an ultrasonic disperser. A single-layer type photosensitive layer dispersion liquid is prepared and coated on an aluminum alumite-treated aluminum tube to form a photosensitive layer having a thickness of about 23 μm, which is then heat treated at about 100 ° C. to form an electrophotographic photosensitive member. Created.

Example 2 A single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 0.15 part by weight of the α-type oxotitanyl phthalocyanine of Example 1 was used.

Example 3 A single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 0.05 part by weight of the α-type oxotitanyl phthalocyanine of Example 1 was used.

Example 4 A single-layer type electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that 10 parts by weight of 9-carbazolyliminofluorene was added.

Example 5 3,3'-Dimethyl-N, N, N ', N'-tetrakis-4-methylphenyl (1,1'-biphenyl) -used in Example 1
Using 30 parts by weight instead of 95 parts by weight of 4,4'-diamine, N-
Ethyl-3-carbazolyl aldehyde N, N-diphenylhydrazone, except that 70 parts by weight of N, N, N ', N'-tetrakis (3-tolyl) -1,3-phenylenediamine are used instead of 5 parts by weight. In the same manner as in Example 1, a single-layer type electrophotographic photoreceptor was prepared.

Example 6 3,3'-Dimethyl-N, N, N ', N'-tetrakis-4-methylphenyl (1,1'-biphenyl) -used in Example 1
70 parts by weight instead of 95 parts by weight of 4,4'-diamine, N-
Ethyl-3-carbazolyl aldehyde N, N'-bis (4-tolyl) -N, N'-bis (3-tolyl) -1,3-phenylenediamine instead of 5 parts by weight of N, N-diphenylhydrazone A single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 30 parts by weight was used.

Example 7 A single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 5 except that 10 parts by weight of 9-carbazolyliminofluorene was added.

Example 8 Further, a single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 6 except that 10 parts by weight of 9-carbazolyliminofluorene was added.

Comparative Example 1 A single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 0.01 part by weight of the α-type oxotitanyl phthalocyanine of Example 1 was used.

Comparative Example 2 A single-layer type electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 0.3 part by weight of the α-type oxotitanyl phthalocyanine of Example 1 was used.

Comparative Example 3 3,3′-Dimethyl-N, N, N ′, N′-tetrakis-4 without adding N-ethyl-3-carbazolylaldehyde N, N-diphenylhydrazone used in Example 1 -Methylphenyl (1,1'-biphenyl) -4,4'-diamine A single-layer type electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that 100 parts by weight was used instead of 95 parts by weight. did.

Comparative Example 4 3,3'-Dimethyl-N, N, N ', N'-tetrakis-4-methylphenyl (1,1'-biphenyl) -used in Example 1
In the same manner as in Example 1 except that 4,4'-diamine was not added and 100 parts by weight was used instead of 5 parts by weight of N-ethyl-3-carbazolylaldehyde N, N-diphenylhydrazone. A layer type electrophotographic photoreceptor was prepared.

Then, in order to examine the charging characteristics and the photosensitive characteristics of the electrophotographic photoreceptors obtained in the above-mentioned Examples and Comparative Examples, an electrostatic copying test apparatus (Gentec Cynthia 30 manufactured by Gentec Co., Ltd.) was used.
M) was used to positively charge each of the electrophotographic photoconductors.

Incidentally, the measured surface potential V _SP (V) of the electrophotographic photosensitive member, using a tungsten lamp of the illuminance 10 lux, and the exposure surface of an electrophotographic photoreceptor, the surface potential V _SP
The half-exposure dose E1 / 2 (μJ / c
m ² ) was calculated. The surface potential 0.15 seconds after the exposure was taken as the residual potential V _rp (V).

Further, it was also examined whether or not the surface potential was lowered by repeated use 1000 times. By the repeated use of the photoreceptor, the surface potential of the photoreceptor was reduced by 100 V or more was evaluated as ×, and the reduction in the range of 50 to 100 V was evaluated as Δ, and only 50 V or less was evaluated as ○. .

Furthermore, after copying a gray original with the same lightness as red and measuring the reflection density of the obtained copy with a reflection densitometer, The red reproducibility was examined by calculating The red reproducibility of 70% or less was evaluated as x, the range of 70 to 100% was evaluated as Δ, and the 100% or more was evaluated as o.

Table 1 shows the results of the charging characteristics, the photosensitive characteristics, etc. of the electrophotographic photosensitive members obtained in the above Examples and Comparative Examples.

As is clear from Table 1, the electrophotographic photoreceptors of Examples 1 to 8 all have excellent charging characteristics and high sensitivity,
It was found that the residual potential was small and the repeatability and red color reproducibility were excellent.

On the other hand, the electrophotographic photosensitive members of Comparative Examples 1 to 4 are all excellent in red color reproducibility, but their repeating characteristics are insufficient. Furthermore, Comparative Example 1 and Comparative Example 4
The electrophotographic photosensitive member of No. 1 had low sensitivity and high residual potential.

(Effects of the Invention) As described above, according to the electrophotographic photosensitive member of the present invention, the charging characteristics are excellent, the sensitivity is high, the residual potential is small, and further, the repeating characteristics and the red color reproducibility are also excellent. Also,
Since it is a single-layer type photoreceptor, it has not only excellent positive charging property but also a unique effect that it can be easily manufactured with high yield and is inexpensive.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-207148 (JP, A) JP-A-62-242951 (JP, A)

Claims (3)

[Claims] 1. The following general formula [1] is used as a charge generating material in a binder resin. (Wherein R ¹ , R ² , R ³ , and R ⁴ represent an alkyl group), and the above-mentioned perylene compound 10
0.62 to 1.88 parts by weight of oxotitanyl phthalocyanine with respect to 0 parts by weight, and the following general formula [I
I] And a hydrazone-based compound represented by the following general formula [III], a fluorene-based compound represented by the following general formula [IV], and m- represented by the following general formula [V]. An electrophotographic photoreceptor, comprising: forming a photosensitive layer containing at least one selected from the group consisting of phenylenediamine compounds on a conductive substrate. (In the formula, R ⁵ represents a hydrogen atom or an alkyl group) (In the formula, R ⁶ , R ⁷ , R ⁸ and R ⁹ represent a hydrogen atom or an alkyl group) (In the formula, R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , and R ^{14 each} represent an alkyl group, an alkoxyl group, or a halogen atom. And all the substituents may be the same or different from each other). 2. The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains an antioxidant. 3. A perylene-based compound is N, N'-bis (3,5-
The electrophotographic photosensitive member according to claim 1, which is dimethylphenyl) perylene-3,4,9,10-tetracarboxydiimide.