JPH07258190A - Trinitrofluorenoneimine derivative and electrophotographic receptor - Google Patents

Abstract

PURPOSE:To obtain the novel compound having excellent electron transporting properties, capable of providing an electrophotographic receptor having high sensitivity in the case of using an electron transporting agent. CONSTITUTION:A trinitrofluorenoneimine derivative of the formula I (R is an alkyl, an alkoxy or a halogen; (n) is an integer of 0-4) such an N-(5,6,7,8- tetrahydro-1-naphthyl)-2,4,7-trinitrofluorenoneimine. The compound of the formula I, for example, is obtained by condensing 2,4,7-trintrofluorenone of the formula II with 5-amino-1,2,3,4-tetralin or its derivative in a solvent (e.g. acetic acid or propionic acid). When the compound of the formula I is used as an electron transporting agent in an electrophotographic receptor contained in a binder resin, the speed of a copying machine or a printer can be increased. The electrophotographic receptor is preferably mixed with phthalocyanine-based pigment as a charge generating agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel trinitrofluorenone imine derivative, and an electrophotographic photoreceptor used in an image forming apparatus such as a copying machine or a laser printer.

[0002]

2. Description of the Related Art Recently, in an image forming apparatus of a digital optical system using a light source having a wavelength of 700 nm or more, an organic photoconductor (OPC) having sensitivity in the wavelength region is required. Many are used. As the organic photoconductor, there are many so-called function-separated type organic photoconductors in which a charge generation layer and a charge transport layer are laminated, that is, a laminated photoconductor, but the charge generation substance and the charge transport substance are dispersed in the photoconductor layer. A single-layer type organic photoconductor is also known.

Charge transport materials used in these photoreceptors are required to have a high carrier mobility. However, most of the charge transport materials having a high carrier mobility have a hole transporting property, and therefore are practically used. In view of mechanical strength, the negative charge type laminated organic photoreceptor having a charge transport layer as the outermost layer is limited. However, the negatively charged type organic photoconductor uses a negative corona discharge, so that it produces a large amount of ozone, and thus has a problem that it pollutes the environment and deteriorates the photoconductor.

Therefore, in order to eliminate such drawbacks, the use of an electron transfer material as a charge transfer material has been studied, and JP-A-1-206349 discloses an electrophotographic compound having a diphenoquinone structure. It has been proposed to use it as an electron transfer material for photoreceptors. However, in general, electron transfer agents such as diphenoquinones are difficult to match with the charge generation agent, and therefore electron injection from the charge generation agent to the electron transfer agent is insufficient, and thus photosensitivity is insufficient. . Further, in the single-layer type organic photosensitive layer, there is a problem that the electron transport is hindered by the interaction between the diphenoquinone and the hole transport material.

Regarding the charging polarity of the photosensitive member, if one photosensitive member can be used for both positive charging and negative charging, the application range of the photosensitive member can be expanded. Further, if the organic photoconductor can be used in a single-layer dispersion type, the photoconductor can be easily manufactured, there are many advantages in preventing the occurrence of coating defects and improving the optical characteristics. A main object of the present invention is to solve the above technical problems and to provide a novel compound suitable as an electron transporting agent for an electrophotographic photoreceptor.

Another object of the present invention is to provide an electrophotographic photosensitive member in which electrons are smoothly injected and transported from a charge generating agent and the sensitivity is improved as compared with the conventional one. Still another object of the present invention is to provide an electrophotographic photosensitive member which can be positively charged. A further object of the present invention is to provide an electrophotographic photosensitive member which is suitable for use in an image forming apparatus of a digital optical system using a light source having a wavelength of 700 nm or more.

[0007]

Means and Actions for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above objects, and as a result, the general formula:

[0008]

[Chemical 3]

(In the formula, R represents an alkyl group, an alkoxy group or a halogen atom. N is an integer of 0 to 4.)
The inventors have found that the trinitrofluorenone imine derivative represented by the formula (4) has a higher electron transporting capacity than the conventional diphenoquinone compounds, and have completed the present invention. The compound represented by the general formula in the present invention has good solubility in a solvent and compatibility with a binder resin, and an electron is smoothly injected with excellent matching with a charge generating agent,
In particular, it excels in electron transport property in a low electric field.

Therefore, when the trinitrofluorenone imine derivative represented by the above general formula of the present invention is used as an electron transporting agent in an electrophotographic photoreceptor, a highly sensitive organic photoreceptor can be provided. The compounds of the present invention are also safe against carcinogenicity. Furthermore, the compound of the present invention utilizes the high electron-transporting ability of the solar cell,
It can also be used for applications such as EL devices.

Each group represented by the above general formula will be specifically described. Examples of the alkyl group include methyl,
Examples thereof include alkyl groups having 1 to 6 carbon atoms such as ethyl, n-propyl, isopropyl, t-butyl, pentyl and hexyl groups. As the alkoxy group, for example, methoxy,
Examples thereof include alkoxy groups having 1 to 6 carbon atoms such as ethoxy, propoxy, t-butoxy, pentyloxy and hexyloxy groups.

Examples of the halogen atom include chlorine, bromine, fluorine and iodine. This derivative is obtained by condensing 2,4,7-trinitrofluorenone and 5-amino-1,2,3,4-tetralin or a derivative thereof in a solvent as shown by the following reaction process formula, for example. Can be synthesized by. Examples of the solvent include acetic acid, propionic acid, butanoic acid, chloroform, tetrahydrofuran, dimethylformamide, dimethylsulfoxide and the like. If necessary, the reaction may be carried out in the presence of a suitable catalyst such as zinc chloride. The reaction may be performed usually at a temperature of 30 to 170 ° C. for about 20 minutes to 4 hours.

[0013]

[Chemical 4]

(In the formula, R and n are the same as the above.) Among the compounds of the present invention, the derivative having the simplest structural formula is a compound in which n is 0 in the above general formula. Although it has a high electron-transporting ability as described in Examples below, other compounds of the present invention in which n is an integer of 1 to 4 also show a similar high electron-transporting ability, and have a high solubility in a solvent and There is an advantage that the compatibility with the binder resin is further improved.

The electrophotographic photosensitive member of the present invention has an organic photosensitive layer provided on a conductive substrate, and this organic photosensitive layer is represented by the above-mentioned general formula as an electron transfer agent in a binder resin. It contains a trinitrofluorenone imine derivative. The organic photosensitive layer may be a single layer type containing a charge generating agent and a hole transporting agent together with an electron transporting agent, or may be a laminated type containing a charge transporting layer and a charge generating layer. The photoconductor of the present invention may be either a positive charging type or a negative charging type, but it is particularly preferable to use the positive charging type.

In the positive charging type photoreceptor, the electrons released from the charge generating agent in the exposure step are smoothly injected into the electron transporting agent represented by the above general formula, and then the electrons are transferred between the electron transporting agents. The electrons move to the surface of the photosensitive layer and cancel the positive charge (+) charged on the surface of the photosensitive layer in advance. On the other hand, holes (+) are injected into the hole transfer material, move to the surface of the conductive substrate without being trapped in the middle, and are negatively charged (-) on the surface of the conductive substrate in advance. Canceled. In this way, the sensitivity of the positive charging type photoconductor is considered to be improved.

As the hole-transporting agent, conventionally known hole-transporting substances are used, for example, oxadiazole such as 2,5-di (4-methylaminophenyl) and 1,3,4-oxadiazole. Compounds, styryl compounds such as 9- (4-diethylaminostyryl) anthracene, carbazole compounds such as polyvinylcarbazole, organic polysilane compounds, pyrazoline compounds such as 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline, Hydrazone compounds, triphenylamine compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, nitrogen-containing cyclic compounds such as triazole compounds, Such as condensed polycyclic compounds .

These hole transport agents may be used alone or in combination of two or more. Further, when using a hole transporting agent having film-forming properties such as polyvinylcarbazole, the binder resin is not always necessary. Among the hole transport materials,
Particularly, those having an ionization potential of 5.0 to 5.6 eV are preferably used. Also, the electric field strength is 3 × 10 ^-5 V
Those having a mobility of 10 ⁻⁶ Vcm or more in / cm are particularly preferable.

The hole transporting agent used in the present invention is not particularly limited, but for example, 1,1
-Bis (4-diethylaminophenyl) -4,4-diphenyl-1,3-butadiene, N-ethyl-3-carbazolylaldehyde diphenylhydrazone, p-N, N-
Diethylbenzaldehyde diphenylhydrazone, 4-
[N, N-bis (p-toluyl) amino] -β-phenylstilbene and the like can be mentioned.

The value of the ionization potential is measured by using an atmospheric photoelectron analyzer (AC-1 manufactured by Riken Keiki Co., Ltd.). In the present invention, by using a hole transfer agent having an ionization potential within the above range, the residual potential can be further lowered and the sensitivity can be improved. The reason is not clear, but it is considered as follows.

That is, the easiness of injecting charges from the charge generating agent into the hole transferring material is closely related to the ionization potential of the hole transferring material, and the ionization potential of the hole transferring material is higher than the above range. If it is large, the degree of charge injection from the charge generating agent to the hole transporting agent will be low, or the degree of transfer of holes between the hole transporting agents will be low, resulting in a decrease in sensitivity. Is recognized.

On the other hand, in a system in which a hole transfer material and an electron transfer material coexist, it is necessary to pay attention to the interaction between them and more specifically to the formation of a charge transfer complex. When such a complex is formed between the two, recombination occurs between the holes and the electrons, and the mobility of the charge is lowered as a whole. When the ionization potential of the hole transfer material is smaller than the above range, the tendency to form a complex with the electron transfer material increases, and electron-hole recombination occurs, resulting in an apparent quantum yield. Is likely to decrease, resulting in a decrease in sensitivity.

Therefore, the ionization potential of the hole transfer material is preferably within the above range. Further, in the system in which the hole transfer material and the electron transfer material coexist, a material having a bulky substituent introduced therein is used as the electron transfer material, and a complex with the hole transfer material due to steric hindrance is used. Formation is preferably suppressed. In that sense as well, it can be said that it is preferable to use the bulky compound of the present invention to which a tetrahydronaphthyl group which may have a substituent is bonded.

Examples of the charge generating agent used in the present invention include selenium, selenium-tellurium, amorphous silicon, pyrylium salts, azo pigments, disazo pigments,
Ansanthuron pigment, phthalocyanine pigment, naphthalocyanine pigment, indigo pigment, triphenylmethane pigment, slene pigment, toluidine pigment, pyrazoline pigment, quinacridone pigment, dithioketopyrrolopyrrole pigment, etc. . These charge generating agents may be used alone or in combination of two or more so as to have an absorption wavelength in a desired region. At that time, in connection with using a hole transfer agent having an ionization potential of 5.0 to 5.6 eV, a charge generation agent having an ionization potential balanced with the hole transfer agent, specifically, Has an ionization potential of 5.0 to 5.
It is desirable to use 6 eV, particularly 5.32 to 5.38 eV, in order to reduce the residual potential and improve the sensitivity.

Particularly, as the charge generating agent suitable for the organic photoconductor used in the above-mentioned image forming apparatus of the digital optical system and having a sensitivity in the wavelength region of 700 nm or more,
Examples thereof include phthalocyanine-based pigments such as X-type metal-free phthalocyanine and oxotitanyl phthalocyanine. Since these phthalocyanine pigments are excellent in matching with the compound (electron transfer agent) of the present invention represented by the above general formula, the electrophotographic photoreceptor using both of them has high sensitivity in the above wavelength range, It can be suitably used for an image forming apparatus of an optical system.

As the binder resin for dispersing the above components, various resins conventionally used in organic photosensitive layers can be used, for example, a styrene polymer,
Styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer, polyethylene, ethylene-vinyl acetate copolymer, chlorinated polyethylene, poly Vinyl chloride, polypropylene, ionomer, vinyl chloride-vinyl acetate copolymer, polyester,
Alkyd resin, polyamide, polyurethane, polycarbonate, polyarylate, polysulfone, diallylphthalate resin, ketone resin, polyvinyl butyral resin,
Thermoplastic resin such as polyether resin, polyester resin, silicone resin, epoxy resin, phenol resin,
Examples thereof include urea resins, melamine resins, other crosslinkable thermosetting resins, and photocurable resins such as epoxy acrylate and urethane-acrylate. These binder resins can be used alone or in combination of two or more. Suitable resins are styrene polymers, acrylic polymers, styrene-acrylic copolymers, polyesters, alkyd resins, polycarbonates, polyarylates and the like.

In the photosensitive layer, various additives known per se, such as an antioxidant, a radical scavenger, a singlet quencher, and the like, may be used as long as they do not adversely affect the electrophotographic characteristics.
A deterioration inhibitor such as an ultraviolet absorber, a softening agent, a plasticizer, a surface modifier, a bulking agent, a thickener, a dispersion stabilizer, a wax, an acceptor, a donor and the like can be added. The amounts of these additives to be added may be the same as conventional amounts. For example, the sterically hindered phenolic antioxidant is preferably added in an amount of about 0.1 to 50 parts by weight with respect to 100 parts by weight of the binder resin.

In order to improve the sensitivity of the photosensitive layer,
For example, known sensitizers such as terphenyl, halonaphthoquinones and acenaphthylene may be used in combination with the charge generating agent.
In addition to the compound represented by the above general formula, other conventionally known electron transfer agents may be contained in the photosensitive layer. Examples of such electron transfer agents include benzoquinone-based, diphenoquinone-based, malononitrile, thiopyran-based compounds, tetracyanoethylene, 2,4,8-trinitrothioxanthone, 3,4,5,7-tetranitro-9-fluorenone and the like. Fluorenone compounds, dinitrobenzene, dinitroanthracene, dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride,
Examples thereof include maleic anhydride and dibromomaleic anhydride.

As the electroconductive substrate used in the photoreceptor of the present invention, various electroconductive materials can be used. For example, aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium and cadmium. Examples include simple metals such as titanium, nickel, palladium, indium, stainless steel, and brass, plastic materials in which the above metals are vapor-deposited or laminated, and glass coated with aluminum iodide, tin oxide, indium oxide, or the like. .

The conductive substrate may be in the form of a sheet, a drum, or the like, as long as the substrate itself has conductivity or the surface of the substrate has conductivity. Further, it is preferable that the conductive substrate has sufficient mechanical strength when used. The photosensitive layer according to the present invention is manufactured by coating a coating solution prepared by dissolving or dispersing a resin composition containing each of the above components in a solvent on a conductive substrate and drying the coating solution.

The effect of the use of the electron transfer agent in the present invention is remarkable in the single-layer type photoreceptor. The single-layer type photoreceptor of the present invention can be applied to both positive charging and negative charging, but it is particularly preferable to use the positive charging type. In the single-layer type photoreceptor, the charge generating agent is the binder resin 10
0.5 to 10 parts by weight, especially 0.5 to 0 parts by weight
It is preferable to add 5 parts by weight to the photosensitive layer.

The hole transfer agent is preferably contained in the photosensitive layer in an amount of 5 to 100 parts by weight, particularly 50 to 80 parts by weight, based on 100 parts by weight of the binder resin. The electron transfer agent is preferably added to the photosensitive layer in an amount of 5 to 100 parts by weight, particularly 10 to 80 parts by weight, based on 100 parts by weight of the binder resin.
In the single-layer type photoreceptor, the thickness of the photosensitive layer is 5 to 50 μm,
In particular, it is preferable that the thickness is about 10 to 40 μm.

In order to obtain a laminated type photoreceptor, a charge generating material is vapor-deposited alone on a conductive substrate to form a charge generating layer, or a charge generating material and a binder resin are applied by means such as coating. If necessary, a charge generating layer containing a hole transferring material may be formed, and a charge transferring layer containing the compound of the present invention as an electron transferring material and a binder resin may be formed on the charge generating layer. . Alternatively, conversely to the above, the charge transport layer may be formed on the conductive substrate, and then the charge generation layer may be formed.

In the laminated photoreceptor, the charge generating material and the binder resin forming the charge generating layer can be used in various ratios, but the charge generating material 5 to 5 parts by weight relative to 100 parts by weight of the binder resin. It is preferably used in an amount of 1000 parts by weight, particularly 30 to 500 parts by weight. The electron-transporting agent and the binder resin constituting the charge-transporting layer can be used in various proportions within a range that does not hinder the transport of electrons and a range that does not crystallize. 10 to 500 parts by weight, particularly 25 to 20 parts by weight of an electron transfer agent, relative to 100 parts by weight of the binder resin, so that electrons can be easily transported.
It is preferably used in a proportion of 0 parts by weight.

The thickness of the laminated photosensitive layer is preferably 0.01 to 5 μm, particularly 0.1 to 3 μm for the charge generation layer, and 2 to 100 μm for the charge transport layer.
It is preferable that it is formed to a thickness of m, especially about 5 to 50 μm. In the single-layer type photoreceptor, between the conductive substrate and the photosensitive layer, in the laminated type photoreceptor, between the conductive substrate and the charge generation layer, or between the conductive substrate and the charge transport layer. In between, a barrier layer may be formed in a range that does not impair the characteristics of the photoreceptor. A protective layer may be formed on the surface of the photosensitive layer.

When the above-mentioned photosensitive layer is formed by a coating method, the above-mentioned charge generating material, charge transporting material, binder resin and the like are used together with a suitable solvent by a known method, for example,
A dispersion may be prepared by dispersing and mixing using a roll mill, a ball mill, an attritor, a paint shaker, an ultrasonic disperser, or the like, and the dispersion may be applied and dried by a known means.

As the solvent for forming the dispersion liquid, various organic solvents can be used. For example, alcohols such as methanol, ethanol, isopropanol and butanol, and aliphatic hydrocarbons such as n-hexane, octane and cyclohexane. , Benzene, toluene, xylene and other aromatic hydrocarbons, dichloromethane, dichloroethane, carbon tetrachloride, chlorobenzene and other halogenated hydrocarbons, dimethyl ether, diethyl ether, tetrahydrofuran,
Examples thereof include ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and methyl acetate, dimethylformaldehyde, dimethylformamide and dimethyl sulfoxide. These solvents can be used alone or in combination of two or more.

Further, in order to improve the dispersibility of the charge transport material and the charge generating material and the smoothness of the surface of the photosensitive layer, a surfactant, a leveling agent, etc. may be used.

[0039]

EXAMPLES The present invention will be described below with reference to examples. Example N- (5,6,7,8-tetrahydro-1-naphthyl)
-Preparation of 2,4,7-trinitrofluorenone imine 2.4,7-Trinitrofluorenone 3.15 g (1
(0.00 mmol) and 1-amino-5,6,7,8-tetrahydronaphthalene (1.77 g, 12.00 mmol) were dissolved in 50 ml of acetic acid and reacted at 110 ° C for 2 hours. After the reaction, it was added to 300 ml of water, and the precipitated crystals were washed with water. The crystals were dried and then purified by silica gel column chromatography (eluted with chloroform: hexane = 1: 2) to give 1.46 g of the title compound (a compound in which n in the general formula is 0) as a dark red powder. Yield 33%) was obtained.

The melting point of this product was 241 ° C. The infrared absorption spectrum of this product is shown in FIG. (Evaluation of electron transporting ability) The electron transporting ability of the compounds obtained in the examples was evaluated by the TOF method. As a result, this compound showed 4.08 × 10 ⁻⁷ cm ² / V at an electric field strength of 3 × 10 ⁵ V / cm.
・ It showed a mobility of seconds and was found to have a high electron transporting ability. (Production of Photoreceptor) Sample No. 1-5
Was produced. Sample No. The compound obtained in the example was used as the one- electron transfer agent, and the X-type metal-free phthalocyanine (Ip =
5.38 eV) and using p-N,
N-diethylbenzaldehyde diphenylhydrazone (Ip = 5.20 eV) was used. Further, polycarbonate was used as a binder resin, and these materials were mixed and dispersed in a predetermined amount of dichloromethane with a ball mill to prepare a single-layer type photosensitive layer coating solution. Then, after applying this coating solution on an aluminum foil with a wire bar,
It was dried with hot air for 0 minutes to prepare a single-layer type electrophotographic photosensitive member having a film thickness of 15 to 20 μm.

(Component) (Parts by Weight) Charge Generating Agent 1 Hole Transfer Agent 60 Electron Transfer Agent 40 Binder Resin 100 Sample No. Sample No. 2 as a charge generating agent In place of the compound used in 1, oxotitanyl phthalocyanine (Ip = 5.32e
V) was used, and sample No. A single layer type electrophotographic photosensitive member was produced in the same manner as in 1. Sample No. As a 3 electron transfer agent, 2,6-, instead of the compound obtained in the example
Dimethyl-2 ', 6'-di-t-butyl-4,4'-diphenoquinone was used, except for sample No. A single layer type electrophotographic photosensitive member was produced in the same manner as in 1. Sample No. 4 Sample No. 4 except that it does not contain an electron transfer agent. A single layer type electrophotographic photosensitive member was produced in the same manner as in 1. Sample No. Sample No. 5 as a charge generating agent. 100 parts by weight of the same compound as used in Example 1, 100 parts by weight of polyvinyl butyral resin as a binder resin, and a predetermined amount of tetrahydrofuran as a solvent were mixed and dispersed by a ball mill to prepare a coating solution for the charge generation layer. This coating solution was applied onto an aluminum foil with a wire bar and then dried with hot air at 100 ° C. for 60 minutes to form a charge generation layer having a film thickness of about 1 μm.

On the other hand, 100 parts by weight of the compound obtained in the example as an electron transfer agent, 100 parts by weight of a polycarbonate resin as a binder resin and a predetermined amount of toluene as a solvent were mixed and dispersed by a ball mill to obtain a coating liquid for a charge transport layer. Prepared. This coating solution was applied onto the charge generation layer with a wire bar, and then dried with hot air at 100 ° C. for 60 minutes to form a charge transport layer having a film thickness of 20 μm, and a positive charging type laminated photoreceptor was produced. . Sample No. Instead of the compound obtained in the example as a 6- electron transfer agent, 2,6-
Dimethyl-2 ', 6'-di-t-butyl-4,4'-diphenoquinone was used, except for sample No. In the same manner as in No. 5, a positive charging type laminated photoconductor was produced. (Evaluation of Electrophotographic Photoreceptor) Using an electrostatic copying tester (EPA-8100 manufactured by Kawaguchi Electric Co., Ltd.), an applied voltage was applied to the photoreceptor of each sample to positively charge it, and white halogen light as a light source was used. The electrophotographic characteristics were measured by using monochromatic light having a wavelength of 780 nm (half-value width of 20 nm) extracted by using a bandpass filter. The results are shown in Table 1.

In the table, V1 indicates the initial surface potential of the photoconductor when the photoconductor is charged by applying a voltage, and V2 is measured as the residual potential, which is the surface potential 0.8 seconds after the start of exposure. It is a thing. E1 / 2 is the half exposure amount when the initial surface potential V1 is attenuated to 1/2.

[0044]

[Table 1]

From Table 1, sample No. in which the compound of the present invention was used as an electron transfer agent. It can be seen that the photoconductors 1, 2, and 5 have high sensitivity because the residual potentials are lowered.

[0046]

The compound of the present invention has an effect of excellent electron transporting property. Therefore, the electrophotographic photosensitive member using the compound of the present invention as an electron transfer material has an effect of excellent sensitivity. Further, in particular, the electrophotographic photosensitive member using the compound of the present invention as an electron transporting agent in combination with a phthalocyanine pigment as a charge generating agent was used in a digital optical image forming apparatus using a light source having a wavelength of 700 nm or more. In that case, there is an effect that the sensitivity is high.
Therefore, when the photoconductor of the present invention is used, the speed of a copying machine, a printer or the like can be increased.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum of the product obtained in the example.

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[Procedure amendment]

[Submission date] June 17, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

These hole transport agents may be used alone or in combination of two or more. Further, when using a hole transporting agent having film-forming properties such as polyvinylcarbazole, the binder resin is not always necessary. Among the hole transport materials,
Particularly, those having an ionization potential of 5.0 to 5.6 eV are preferably used. In addition, the electric field strength is 3 × 10 ⁵ V
Those having a mobility of 1 × 10 ⁻⁶ cm ² / V · sec or more in / cm are particularly preferable.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Fukami 1-2-2 Tamatsukuri, Chuo-ku, Osaka-shi, Osaka Mita Industry Co., Ltd.

Claims (3)

[Claims] 1. A general formula: (In formula, R shows an alkyl group, an alkoxy group, or a halogen atom. N is an integer of 0-4.) The trinitrofluorenone imine derivative represented by these. 2. An electrophotographic photoreceptor having an organic photosensitive layer provided on a conductive substrate, wherein the organic photosensitive layer is contained in a binder resin.
An electrophotographic photoreceptor comprising a trinitrofluorenone imine derivative represented by the following general formula as an electron transfer agent. [Chemical 2] (In the formula, R represents an alkyl group, an alkoxy group, or a halogen atom. N is an integer of 0 to 4.) 3. The electrophotographic photosensitive member according to claim 2, which contains a phthalocyanine pigment as a charge generating agent.