JP3470160B2 - Electrophotographic photoreceptor - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic photoreceptor for forming an electrostatic latent image, and more particularly to an electrophotographic photoreceptor having a photosensitive layer containing a compound having an electron transporting ability. .

[0002]

2. Description of the Related Art In the electrophotographic process, the surface of an electrophotographic photosensitive member is uniformly charged, the surface of the charged photosensitive member is exposed imagewise, and an electrostatic latent image is formed on the surface of the electrophotographic photosensitive member. The basic principle is that the electrostatic latent image is formed and developed by a developer such as toner to be visualized. Therefore, the electrophotographic photoreceptor used in this process needs to have good chargeability and rapid surface potential decay by light irradiation, and the characteristics required for the electrophotographic photoreceptor in these processes are solid physical property values. That is, the dark resistance is high, the quantum efficiency for generating charge carriers is good, and the charge mobility is high.

Conventionally, electrophotographic photoreceptors composed of inorganic compounds such as selenium, selenium-tellurium alloys, and selenium-arsenic have been adopted to satisfy these physical property values and have been used in many copying machines. However, since these materials have environmental problems such as toxicity and are used in an amorphous state, they are difficult to handle because, for example, they are easily crystallized due to heat, dirt, etc. and their characteristics are deteriorated. Also,
Since it is necessary to perform vacuum deposition to a film thickness of several tens of μm, there are drawbacks such as high cost.

Therefore, recently, research on an electrophotographic photosensitive member using an organic photoconductive substance has progressed, and a part thereof has been put to practical use. Most of the organic electrophotographic photoreceptors that have been put to practical use are laminated electrophotographic photoreceptors composed of a photosensitive layer having a charge-generating layer and a charge-transporting layer with separated functions. Compared with other electrophotographic photoreceptors, the sensitivity and photoreceptor life, which were inferior to those of other electrophotographic photoreceptors, have been improved, there are few problems in terms of safety at low cost, and the advantages of organic photoconductive substances in terms of material diversity, etc. Making the most of this, the development of electrophotographic photoconductors has become active.

In this type of laminated electrophotographic photoreceptor, generally, a charge generating layer made of a charge generating substance such as a pigment or a dye and a charge transporting layer made of a charge transporting substance such as hydrazone or pyrazoline are formed on a conductive substrate. Due to the nature of the electron-donating charge-transporting substance, which has a laminated photosensitive layer,
It is of the hole transfer type and has sensitivity when the surface of the photoreceptor is negatively charged. However, with negative charging, the corona discharge used during charging is more unstable than with positive charging, and ozone, nitrogen oxides, etc., which are about 10 times the positive charge, are generated, and the electrophotographic photosensitive member is adsorbed on the surface of the photosensitive layer. However, there is a problem in that it is liable to cause physical deterioration and chemical deterioration of the above, and also has an adverse effect on the environment. Further, development of a negative charging photoreceptor requires a positive polarity toner (developer), but the positive polarity toner is difficult to produce in view of the triboelectric charging series with respect to the ferromagnetic carrier particles, and is a two-component toner. In the high resistance magnetic brush development method, the negatively charged toner (developer) is more stable, and the degree of freedom in selection and use conditions is greater. From this point as well, a positively charged electrophotographic photoreceptor is desirable, and organic photoconductive Various proposals have been made for using an electrophotographic photoreceptor using a substance with a positive charge. For example, a charge generating layer containing a charge generating substance that generates holes and electrons when irradiated with light is an upper layer (surface layer), and a charge transporting layer containing a charge transporting substance having a hole transporting ability is a lower layer. The use of an electrophotographic photosensitive member having a photosensitive layer having a laminated structure as follows for positive charging has been studied. However, when such an electrophotographic photosensitive member is used for positive charging, it does not yet have sufficient performance in terms of durability and environmental characteristics. Therefore, in order to solve such a problem, an electrophotographic photoreceptor having a laminated structure in which a charge transporting layer containing a substance having an electron transporting ability as a charge transporting substance is formed on a charge generating layer has been studied, 2,4,7-Trinitro-9-fluorenone is known as such an electron transport substance. However, this substance has industrial health problems such as carcinogenicity.

Further, research has been conducted on an electrophotographic photosensitive member having a single-layer photosensitive layer as the electrophotographic photosensitive member used in the positive charging system. Among conventional single-layer type electrophotographic photoreceptors,
In the form in which the charge generation substance is dispersed in the resin, the charge generation substance also has a charge transfer function, but the sensitivity is low because there are few charge generation substances with good charge transfer characteristics for both holes and electrons. In addition, there is a defect that the charging potential is lowered by repeated use. In order to improve the hole-transporting ability of such an electrophotographic photoreceptor, even if a hole-transporting substance is simply added, the sensitivity is low and the charging potential is lowered during repeated use. It wasn't done.

Therefore, an attempt was made to improve the above-mentioned drawbacks by dispersing a charge generating substance and an electron transporting substance in a resin to form a photosensitive layer, and by further incorporating a hole transporting substance in the resin, Attempts have been made to improve the effect. Further, as an electron transporting material used for such a photosensitive layer, a diphenoquinone compound is disclosed in JP-A-4-285670, but it has insufficient sensitivity and is practically more effective in terms of repetitive characteristics. Improvement is needed. Further, as an electron transporting substance, JP-A-60-6
9657 discloses a fluorenidene methane compound, and JP-A 61-233750 discloses an antoquinodimethane and anthrone derivatives, but these are inferior in terms of repetitive properties, and JP -2513
No. 6 discloses a naphthalene dicarboxylic acid imide compound,
Japanese Unexamined Patent Publication (Kokai) No. 5-25174 discloses a naphthalenetetracarboxylic acid diimide compound, which has insufficient sensitivity and poor compatibility with a binder resin, and thus needs further improvement in practical use. Is the actual situation.

[0008]

The conventional electrophotographic photosensitive member using the electron transporting material has a problem that the sensitivity is insufficient, the residual potential is large, and the repeating property is poor. An object of the present invention is to use a charge-transporting substance having an electron-transporting ability, to provide an electron with excellent chargeability, high sensitivity, a small residual potential, and excellent durability that does not change their characteristics even after repeated use. To provide a photographic photoreceptor.

[0009]

According to the present invention , the following is provided.
An invention is provided . (1) An electrophotographic photosensitive member comprising a conductive substrate and at least a photosensitive layer formed thereon, wherein the photosensitive layer contains a fluorene compound represented by the following general formula (1).

[Chemical 1] (In the formula, R ₁ and R ₂ each represent a fluoroalkoxycarbonyl group, and m and n are 0 or 1 except when they are 0 at the same time.
Represents the integer. R ₁ and R ₂ may be different groups or the same group. Z represents = C (X) (Y) or = N (W), X and Y are a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted Represents an alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted heterocyclic group, W is a substituted or unsubstituted alkyl group,
It represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. X and Y may be different groups or the same groups. (2) The photosensitive layer comprises two layers of a charge generating layer and a charge transporting layer, and at least the charge transporting layer contains the fluorene compound represented by the general formula (1). Electrophotographic photoreceptor. (3) The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer comprises a single layer containing a charge generating substance and the fluorene compound represented by the general formula (1). (4) The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer comprises a single layer containing a charge generating substance, a hole transporting substance and the fluorene compound represented by the general formula (1).

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION
The inventors have found that the fluorene compound represented by the formula (4) has an excellent electron transporting ability, and have completed the present invention. That is, according to the present invention, a charge-transporting substance having an electron-transporting ability is used to provide excellent chargeability, high sensitivity, a small residual potential, and excellent durability that does not change their characteristics even after repeated use. It is possible to obtain an electrophotographic photosensitive member.

The fluoroalkoxycarbonyl group of R ₁ and R _{2 in} the above general formula (1) includes an alkoxycarbonyl group having a fluorine-substituted alkyl group,
The fluorine-substituted alkyl _{group, -CH 2 CF 3, - (} C
_{H 2) 2 CF 3, -} (CH 2) 3 CF 3, - (CH 2) 4 C
_{F 3, -CH 2 CH 2 F} , - (CH 2) 3 CH 2 F, -CH 2
_{CHF 2, - (CF 2)} 2 CF 3, -CH 2 CF 2 CHFCF
_{3, -CH (CF 3) 2} , - (CH 2) 2 CF 2 CF 3, -C
Examples thereof include fluoroalkyl groups such as H ₂ (CF ₂ ) ₂ CF ₃ and —CH ₂ (CF ₂ ) ₇ CF ₃ .

As the substituted or unsubstituted alkyl group,
Examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group and the like, and a trifluoromethyl group and a trichloromethyl group in which these are substituted with a halogen atom such as a fluorine atom and a chlorine atom.

Examples of the aryl group include a phenyl group and a naphthyl group, and examples of the substituent in the aryl group include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a chlorine atom, a bromine atom and a fluorine atom. And halogen-substituted alkyl groups such as trifluoromethyl group and trichloromethyl group, and cyano groups.

The alkoxycarbonyl group includes methoxy group, ethoxy group, n-propyloxy group, iso-propyloxy group, n-butyloxy group, iso-butyloxy group, n-hexyloxy group, n-octyloxy group, n. -Examples thereof include an alkoxycarbonyl group having an alkoxy group such as a decyloxy group, and examples of the substituent in the alkoxycarbonyl group include a chlorine atom, a bromine atom, a halogen atom such as a fluorine atom, a trifluoromethyl group and a trichloromethyl group. Examples thereof include halogen-substituted alkyl groups.

Examples of the aryloxycarbonyl group include an aryloxycarbonyl group having an aryl group such as a phenyl group and a naphthyl group, and a substituent in the aryloxycarbonyl group is a methyl group, an ethyl group, a propyl group, Examples thereof include an alkyl group such as a butyl group, a halogen atom such as a chlorine atom, a bromine atom and a fluorine atom, a halogen-substituted alkyl group such as a trifluoromethyl group and a trichloromethyl group, and a cyano group.
Examples of the heterocyclic group include a group composed of a heterocycle such as a thiazole ring, an oxazole ring, a benzothiazole ring, and a benzoxazole ring, and a substituent in the heterocycle includes a methyl group, an ethyl group, a propyl group, and a butyl group. Substituted with an alkyl group such as, methoxy group, ethoxy group, propoxy group, alkoxycarbonyl group including alkoxy group such as butoxy group, halogen atom such as chlorine atom, bromine atom, fluorine atom, alkyl group such as methyl group, ethyl group, etc. The amino group, cyano group, nitro group and the like can be exemplified.

Specific examples of the fluorene compound represented by the general formula (1) in the present invention are shown in Tables 1-1 to 1-9 below, but the invention is not limited thereto.

[0017]

[Table 1-1]

[0018]

[Table 1-2]

[0019]

[Table 1-3]

[0020]

[Table 1-4]

[0021]

[Table 1-5]

[0022]

[Table 1-6]

[0023]

[Table 1-7]

[0024]

[Table 1-8]

[0025]

[Table 1-9]

Next, the structure of the electrophotographic photosensitive member of the present invention will be described with reference to the drawings. As the constitution of the electrophotographic photoreceptor of the present invention, for example, as shown in FIG. 1, a charge generating layer 2 containing a charge generating substance and, if necessary, a binder resin on a conductive substrate 1 is used as a lower layer, and an electron transporting substance ( A fluorene compound represented by the general formula (1) and, if necessary, a photosensitive layer 4 having a laminated structure having a charge transport layer 3 containing a binder resin as an upper layer, and a conductive substrate as shown in FIG. 1 and the like, on which a photosensitive layer 5 having a single layer structure containing a charge generating substance, an electron transporting substance and, if necessary, a binder resin is provided. A protective layer may be provided on the photosensitive layer of FIG. 1 or 2, and an undercoat layer may be provided between the conductive substrate and the photosensitive layer. Further, the fluorene compound represented by the general formula (1) may be contained in the photosensitive layer in one kind or two or more kinds.

The charge generating substance used in the electrophotographic photosensitive member of the present invention may be either an inorganic substance or an organic substance as long as it absorbs visible light and generates a free charge. For example, amorphous selenium. , Trigonal selenium,
Inorganic substances such as selenium-arsenic alloy, selenium-tellurium alloy, cadmium sulfide, cadmium selenide, cadmium sulphide selenide, and amorphous silicon, or bisazo dyes, polyazo dyes, triarylmethane dyes, thiazine dyes, oxazine dyes Dyes, xanthene dyes, cyanine dyes, styryl dyes, pyrylium dyes, quinacridone dyes, indigo dyes, perylene dyes,
Examples thereof include organic substances such as polycyclic quinone dyes, bisbenzimidazole dyes, indanthrone dyes, squalium dyes, anthraquinone dyes and phthalocyanine dyes.

Examples of the binder resin used in the photosensitive layer in the present invention include polyethylene, polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin and alkyd. Resins, polycarbonate resins, silicone resins, melamine resins, and other addition-polymerization resins, polyaddition-type resins, polycondensation-type resins, and copolymer resins containing two or more of these resin repeating units, such as vinyl chloride-acetic acid. Examples include insulating resins such as vinyl copolymers and vinyl chloride-vinyl acetate-maleic anhydride copolymers, as well as polymer organic semiconductors such as polyvinylcarbazole. The conductive substrate supporting the photosensitive layer may be a metal plate such as aluminum, nickel, copper, gold or titanium, a metal drum or metal foil, aluminum, tin oxide, indium oxide,
A plastic film obtained by vapor deposition of nickel, titanium, copper, gold or the like, a paper coated with a conductive material, a film made of plastic, or a drum can be used.

In order to prepare an electrophotographic photoreceptor of the present invention having a photosensitive layer formed by stacking a charge generating layer and a charge transporting layer, the charge generating substance is vacuum-deposited on a conductive substrate, or
Alternatively, a charge generating layer coating solution, which is prepared by dissolving or dispersing a charge generating substance in a suitable solvent alone or together with a suitable binder resin, is applied on a conductive substrate and dried to form a charge generating layer. A charge transporting layer is formed by applying a coating solution for a charge transporting layer, which is obtained by dissolving or dispersing the fluorene compound represented by the formula (1) in a suitable solvent alone or with a suitable binder resin, and drying it. do it.

The solvent used for each coating solution is N, N
-Dimethylformamide, toluene, xylene, monochlorobenzene, dichloromethane, 1,2-dichloroethane, 1,1,1-trichloroethane, tetrahydrofuran, methyl ethyl ketone, cyclohexanone, ethyl acetate, butyl acetate and the like can be mentioned.

In order to form the charge generation layer by the coating liquid in which the charge generation substance is dispersed, the charge generation substance is ball-milled,
The particles may be made into fine particles in a dispersion solvent by a homomixer or the like, and if necessary, a binder resin may be added and mixed and dispersed to obtain a dispersion liquid, which may be applied onto a conductive substrate and dried. In this method, it is more preferable to disperse the charge generating substance under the action of ultrasonic waves because uniform dispersion is possible. The particle diameter of the charge-generating substance particles is not more than 2 μm, especially 1
μm or less is preferable. If the particle size is too large, the dispersion in the charge generation layer becomes poor. Further, if the particle size is too small, it tends to aggregate, the resistance of the charge generation layer increases, the crystal defects increase and the sensitivity and repeatability deteriorate, or there is a limit on miniaturization, The lower limit of the average particle size is preferably about 0.01 μm. When a binder resin is used in the charge generation layer, it is preferable that the charge generation material is 20 to 200 parts by weight with respect to 100 parts by weight of the binder resin. The thickness of the charge generation layer is preferably 0.1 to 10 μm, particularly preferably 0.2 to 2 μm.

The charge transport layer comprises a fluorene compound represented by the general formula (1) dissolved or dispersed in a suitable solvent alone or together with a suitable binder resin, and if necessary, a leveling agent such as silicone oil is added to the charge transport layer. It is formed by applying a layer coating liquid on the charge generation layer and drying. When a binder resin is used for the charge transport layer, it is preferable that the fluorene compound represented by the general formula (1) is in a proportion of 20 to 200 parts by weight with respect to 100 parts by weight of the binder resin. The thickness of the charge transport layer is 5
˜50 μm is preferable, and 10˜30 μm is particularly preferable.

In order to prepare the electrophotographic photosensitive member of the present invention having a photosensitive layer having a single layer structure, the charge generating substance and the fluorene compound represented by the general formula (1) are used in a suitable solvent and a suitable binder resin. Dissolve or disperse with
The photosensitive layer may be formed by applying the coating liquid for photosensitive layer onto a conductive substrate and drying it, and the ratio of the charge generating substance and the fluorene compound represented by the general formula (1) contained in the binder resin. As a binder resin 10
It is preferable that the charge generating substance is 1 to 50 parts by weight and the fluorene compound is 5 to 100 parts by weight with respect to 0 part by weight. A hole-transporting substance is added to the photosensitive layer, if necessary, and the proportion thereof is 5 with respect to 100 parts by weight of the binder resin.
It is preferable to set to 100 parts by weight. The thickness of the photosensitive layer having a single-layer structure is preferably 7 to 50 μm, particularly 10 to 30 μm.
m is preferred. The average particle size of the charge-generating substance particles in the photosensitive layer is preferably 2 μm or less, more preferably 1 μm or less. If the particle size is too large, the dispersion in the photosensitive layer becomes poor, and the particles partially project on the surface, resulting in poor surface smoothness. In some cases, discharge may occur at the projected part of the particle or toner particles may be present there. Easily adhere to the toner filming phenomenon. On the other hand, if the particle size is too small, it tends to agglomerate, which increases the resistance of the charge generation layer, increases crystal defects and deteriorates sensitivity and repeatability, or has a limit for miniaturization. The lower limit of the particle size is preferably about 0.01 μm.

As the hole transporting substance added to the photosensitive layer, compounds having a triphenylamine moiety in the molecule, compounds having a carbazole moiety, hydrazone compounds, triphenylmethane compounds, oxazole compounds,
Examples thereof include donor compounds such as styryl compounds, butadiene compounds, polysilane compounds, polyvinylcarbazole, and pyrene-formalin condensates. Specifically, for example, 4'-diphenylamino-α-phenylstilbene, 4'-bis ( 4-Methylphenyl) amino-α-phenylstilbene, N, N′-diphenyl-N, N′-
Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine, 4'-methoxy-N, N-
Diphenyl- [1,1'-biphenyl] -4-amine,
9-ethylcarbazole-3-aldehyde-1-methyl-1-phenylhydrazone, 9-ethylcarbazole-
3-aldehyde-1,1-diphenylhydrazone, 4-
Diethylaminostyryl-3-aldehyde-1-methyl-1-phenylhydrazone, 4-methoxybenzaldehyde-1-methyl-1-phenylhydrazone, 4-diphenylaminobenzaldehyde-1-benzyl-1-phenylhydrazone, 1,1-bis (4-Dibenzylaminophenyl) propane, tris (4-diethylaminophenyl) methane, 1,1-bis (4-dibenzylaminophenyl) propane, 2,2'-dimethyl-4,4'-
Bis (diethylamino) -triphenylmethane, 2,5
-Bis (4-diethylaminophenyl) -1,3,4-
Oxadiazole, 2-N, N-diphenylamino-5
-(4-Diethylaminophenyl) -1,3,4-oxadiazole, 2-N, N-diphenylamino-5-
(N-ethylcarbazol-3-yl) -1,3,4-
Oxadiazole, 3-styryl-9-ethylcarbazole, 3- (4-methoxystyryl) -9-ethylcarbazole, 4-diphenylaminostilbene, 4-dibenzylaminostilbene, 1,4-bis (4-diphenylamino) Styryl) benzene, 1,4-bis [4-di (p-tolyl) aminostyryl] benzene, 1-phenyl-3- (4-diethylaminostyryl) -5- (4-
Diethylaminophenyl) pyrazoline, 1-phenyl-
3- (4-dimethylaminostyryl) -5- (4-dimethylaminophenyl) pyrazoline and the like can be mentioned.

Further, in the electrophotographic photosensitive member of the present invention, an undercoat layer may be provided between the conductive substrate and the photosensitive layer, and the undercoat layer functions as an adhesive layer or a barrier layer. In addition to the above-mentioned binder resin, for example, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, casein, N-alkoxyalkyl nylon or other resin as it is, or a dispersion of tin oxide, indium or titanium oxide, aluminum oxide or oxidation. A vapor-deposited film of silicon or the like is used.
The thickness of the undercoat layer is preferably 2 μm or less.

A protective layer may be provided on the photosensitive layer. As the material for the protective layer, the above-mentioned binder resin is used as it is, or a low resistance substance such as tin oxide or indium oxide is dispersed. Things are suitable. Further, an organic plasma-polymerized film can be used, and the organic plasma-polymerized film may optionally contain oxygen, nitrogen, halogen, and a group III or group V atom of the periodic table.

[0037]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to this. The "parts" indicating the amounts of each material used are parts by weight.

Example 1 5 parts of a bisazo dye represented by the following chemical formula (A), 2.5 parts of butyral resin (Denka butyral resin # 3000-2: manufactured by Denki Kagaku Kogyo KK), and 9 parts of tetrahydrofuran
2.5 parts were dispersed in a ball mill for 12 hours, and then tetrahydrofuran was added so as to have a dispersion liquid concentration of 2% by weight and redispersed to prepare a coating liquid. The coating solution thus prepared was cast-coated on a 100 μm-thick polyester film on which aluminum was vapor-deposited with a doctor blade and dried to form a charge generation layer having a film thickness after drying of 1.0 μm.

[Chemical 2] Next, the exemplified compounds in Table 1 (Compound No. 6)
3) 6 parts, polycarbonate resin (K-1300: manufactured by Teijin Chemicals Ltd.) 10 parts, methylphenyl silicon (KF50)
-100 cps: manufactured by Shin-Etsu Chemical Co., Ltd.) and a coating solution having a formulation of 0.002 parts by weight and 94 parts by weight of tetrahydrofuran are prepared, cast on the charge generation layer with a doctor blade and dried to obtain a film thickness after drying. A 20.0 μm-thick charge transport layer was formed to prepare a laminated electrophotographic photoreceptor (photoreceptor No. 1) composed of an aluminum electrode / charge generation layer / charge transport layer.

Example 2 In Example 1, compound No. 63 in place of Compound No. 63 in the exemplified compounds in Table 1 above. A laminated electrophotographic photosensitive member (photosensitive member No. 2) was prepared in the same manner as in Example 1 except that 33 was used.

Example 3 A charge was obtained in the same manner as in Example 1 except that 6 parts of a trisazo dye represented by the following chemical formula (B) was used in place of 5 parts of the bisazo dye represented by the above chemical formula (A). A generator layer was formed.

[Chemical 3] Next, the exemplified compounds in Table 1 (Compound No. 6)
3) 6 parts, polycarbonate resin (K-1300: manufactured by Teijin Chemicals Ltd.) 10 parts, methylphenyl silicon (KF50)
-100 cps: manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.002 part of tetrahydrofuran, and 94 parts of tetrahydrofuran are prepared, and the solution is cast on the charge generation layer by a doctor blade and dried to obtain a film thickness of 20. A 0 μm-thick charge transport layer was formed, and a laminated electrophotographic photoreceptor (photoreceptor No. 3) composed of an aluminum electrode / charge generation layer / charge transport layer was prepared.

Example 4 In Example 3, the compound No. 63 in place of Compound No. 63 in the exemplified compounds in Table 1 above. A laminated electrophotographic photosensitive member (photosensitive member No. 4) was prepared in the same manner as in Example 3 except that 33 was used.

Example 5 A charge was obtained in the same manner as in Example 1 except that 6 parts of the bisazo dye represented by the following chemical formula (C) was used in place of 5 parts of the bisazo dye represented by the above chemical formula (A). A generator layer was formed.

[Chemical 4] Next, the exemplified compounds in Table 1 (Compound No. 6)
3) 6 parts, polycarbonate resin (K-1300: manufactured by Teijin Chemicals Ltd.) 10 parts, methylphenyl silicon (KF50)
-100 cps: manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.002 part of tetrahydrofuran, and 94 parts of tetrahydrofuran are prepared, and the solution is cast on the charge generation layer by a doctor blade and dried to obtain a film thickness of 20. A 0 μm-thick charge transport layer was formed to prepare a laminated electrophotographic photoreceptor (photoreceptor No. 5) composed of an aluminum electrode / charge generation layer / charge transport layer.

Example 6 In Example 5, compound No. 63 in place of Compound No. 63 in the exemplified compounds in Table 1 above. A laminated electrophotographic photosensitive member (photosensitive member No. 6) was prepared in the same manner as in Example 5 except that 33 was used.

Example 7 Instead of the bisazo dye represented by the chemical formula (A),
Except using X-type metal-free phthalocyanine X-H ₂ Pc is to form a charge generating layer in the same manner as in Example 1. Next, the exemplified compound in Table 1 (Compound No. 63)
6 parts, polycarbonate resin (K-1300: Teijin Chemicals Ltd.) 10 parts, methylphenyl silicone (KF50-1)
(00 cps: manufactured by Shin-Etsu Chemical Co., Ltd.) 0.002 parts, and 94 parts of tetrahydrofuran are prepared, and the solution is cast on the charge generation layer by a doctor blade and dried, and the film thickness after drying is 20.0 μm. The charge transport layer of No. 7 was formed to prepare a laminated electrophotographic photoreceptor (photoreceptor No. 7) composed of an aluminum electrode / charge generation layer / charge transport layer.

Example 8 In Example 7, compound No. 63 in place of Compound No. 63 in the exemplified compounds in Table 1 above. A laminated electrophotographic photosensitive member (photosensitive member No. 8) was prepared in the same manner as in Example 5 except that 33 was used.

Example 9 1 g of X-type metal-free phthalocyanine, polycarbonate Z
(PC-Z) 10 wt% tetrahydrofuran solution 10
and 9 g of tetrahydrofuran were placed in a ball mill pot and milled overnight. Further, 20 g of a 10 wt% tetrahydrofuran solution of PC-Z was added, followed by milling overnight (this is referred to as a 10% dispersion liquid). Next, in a 20 ml sample bottle, 1.2 g of 10% dispersion liquid, 15 w of PC-Z
4.70 g of a t% tetrahydrofuran solution, 0.45 g of a hole transporting substance represented by the following chemical formula (D), 0.27 g of the exemplary compound (Compound No. 63) in Table 1 above, 1.03 g of tetrahydrofuran, and methylphenylsilicon (K
F-50: manufactured by Shin-Etsu Chemical Co., Ltd.) was added 0.15 g of a 1 wt% tetrahydrofuran solution, and the mixture was stirred for 1 hour to prepare a coating liquid for photosensitive layer. The prepared coating liquid was applied onto an aluminum substrate and dried to prepare a single-layer type electrophotographic photosensitive member (photosensitive member No. 9) having a film thickness after drying of 20 μm.

[Chemical 5]

Comparative Example 1 A single-layer type electrophotographic photoreceptor (photoreceptor No. 10) was prepared in the same manner as in Example 9 except that the exemplified compound in Table 1 (Compound No. 63) was not added. About the electrophotographic photosensitive member obtained as described above, using an electrostatic copying paper test device (Kawaguchi Denki Seisakusho: SP-428), +6
After KV corona charging and positive charging, leave in the dark for 20 seconds, measure the surface potential V ₀ at that time, and then use a tungsten lamp so that the illuminance on the surface of the photoconductor becomes 40 lux. The exposure amount E _1/2 (lux · sec) required for the surface potential V _{0 to} be halved was measured by light irradiation. The results are shown in Table 2.

[0048]

[Table 2] As is clear from Table 2, the electrophotographic photosensitive member of the present invention is
Particularly, it is excellent in chargeability and sensitivity in positive charging. Further, the electrophotographic photosensitive member of the present invention showed little change in these characteristics even after repeated use, had a small residual potential, and was excellent in durability.

[0049]

According to the present invention, by containing a fluorene compound having a specific structure having an electron transporting ability in the photosensitive layer, it is excellent in chargeability and sensitivity, especially in positive charging, and has a small residual potential. Further, it is possible to obtain an electrophotographic photosensitive member which is excellent in durability and whose specifications do not change even after repeated use.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing an example of an electrophotographic photosensitive member according to the present invention.

FIG. 2 is a sectional view schematically showing another example of the electrophotographic photosensitive member according to the present invention.

[Explanation of symbols]

1 Conductive substrate 2 Charge generation layer 3 Charge transport layer 4 Laminated photosensitive layer 5 Photosensitive layer composed of a single layer

─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP 54-110837 (JP, A) JP 54-11738 (JP, A) JP 7-175234 (JP, A) JP 7- 70038 (JP, A) JP-A-6-266128 (JP, A) JP-A-2-272570 (JP, A) JP-A-2-268146 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 5/06 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. An electrophotographic photosensitive member comprising at least a photosensitive layer provided on a conductive substrate, wherein the photosensitive layer contains a fluorene compound represented by the following general formula (1). body. [Chemical 1] (In the formula, R ₁ and R ₂ each represent a fluoroalkoxycarbonyl group, and m and n are 0 or 1 except when they are 0 at the same time.
Represents the integer. R ₁ and R ₂ may be different groups or the same group. Z represents = C (X) (Y) or = N (W), X and Y are a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted Represents an alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted heterocyclic group, W is a substituted or unsubstituted alkyl group,
It represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. X and Y may be different groups or the same groups. ) 2. The photosensitive layer is composed of two layers, a charge generation layer and a charge transport layer, and at least the charge transport layer is represented by the general formula (1).
The electrophotographic photosensitive member according to claim 1, further comprising a fluorene compound represented by: 3. The electrophotographic photoreceptor according to claim 1, wherein the photosensitive layer comprises a single layer containing a charge generating substance and the fluorene compound represented by the general formula (1). 4. The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer comprises a single layer containing a charge generating substance, a hole transporting substance and the fluorene compound represented by the general formula (1). .