JPH09208549A - Acenaphthene compound and electrophotographic photoreceptor using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new acenaphthene compound useful as an electron transporting agent capable of actualizing an electrophotographic photoreceptor satisfying characteristics of a photoreceptor, high in sensitivity and durability. SOLUTION: This acenaphthene compound is shown by formula I (Ar1 and Ar3 are each an aryl which may contain a substituent group; Ar2 is phenylene, naphthylene, biphenylene or anthrylene; X is an alkyl which may contain a substituent group or an aryl which may contain a substituent group) such as 5-[N-(4-formylphenyl)-N-phenylamino]acenaphthene of formula II. The compound of formula I is obtained, for example, by formylating 5-(N,N-diphenylamino) acenaphthene derivative of formula III with N,N-dimethylformamide, etc., to give an aldehyde compound of formula IV and reacting this compound with a hydrazine compound of formula V.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel acenaphthene compound useful as a charge transport agent used in an electrophotographic photoreceptor and an electrophotographic photoreceptor using the compound.

[0002]

2. Description of the Related Art An electrophotographic method is generally a method in which the surface of a photoconductor made of a photoconductive material is charged in the dark, for example, by corona discharge, and then exposed to the light to selectively dissipate the charge in the exposed area. It is a kind of image forming method in which an electrostatic latent image is dispersed to obtain an electrostatic latent image, which is visualized with toner, and then transferred and fixed on paper or the like to obtain an image. As the photoconductor, an inorganic photoconductor containing an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide, or silicon as a main component, and a charge generating agent and a low-molecular weight or high-molecular weight charge transport agent in a binder resin There is an organic photoconductor using an organic compound dispersed in. Inorganic photoconductors have many advantages and have been widely used until now.For example, selenium is difficult to produce, its production cost is high, it is vulnerable to heat and mechanical shock, and it easily crystallizes, resulting in poor performance. Resulting in. Zinc oxide and cadmium sulfide have problems in moisture resistance and mechanical strength, and the dye added as a sensitizer is deteriorated by electrification and exposure, resulting in poor durability. Silicon is also difficult to manufacture and uses a highly irritating gas, so it is expensive and sensitive to humidity.

In recent years, organic photoreceptors using various organic compounds have been studied and widely used for the purpose of overcoming the drawbacks of these inorganic photoreceptors. Organic photoreceptors include a single-layer photoreceptor in which a charge generating agent and a charge transporting agent are dispersed in a binder resin, and a laminated photoreceptor in which a charge generating layer and a charge transporting layer are functionally separated. The function-separated type organic photoconductor has been extensively researched and widely used because of its wide choice of materials and the fact that a photoconductor having any desired performance can be produced relatively easily by combining them.

Examples of the charge generating agent include azo compounds,
Many organic compounds such as bisazo compounds, trisazo compounds, tetrakisazo compounds, thiapyrylium salts, squarylium salts, azurenium salts, cyanine dyes, perylene compounds, metal-free or metal phthalocyanine compounds, polycyclic quinone compounds, thioindigo compounds, or quinacridone compounds. Pigments and dyes have been proposed and put into practical use.

As the charge transfer agent, for example, Japanese Patent Publication No. 34-
Oxadiazole compounds described in JP-A-5466, JP-A-56
No. 123544, Oxazole Compound, Japanese Examined Patent Publication No. 5
JP-A 2-41880, Pyrazoline Compound, JP-B-55
-42380 gazette and Japanese Patent Publication No. 61-40104 gazette,
JP-B-62-35673, JP-B-63-3597
No. 6, hydrazone compound, Japanese Patent Publication No. 58-32372
Compounds disclosed in Japanese Patent Publication No. 63-18738, Japanese Patent Publication No. 63-19867, and Japanese Patent Publication No. 3-393.
No. 06 stilbene compound, JP-A-62-3025
For example, there is a butadiene compound disclosed in Japanese Patent No. Organic photoconductors using these charge-transporting materials have excellent properties and some have been put into practical use, but those that sufficiently satisfy the properties required for electrophotographic photoconductors have not yet been obtained. The current situation is not.

[0006]

The charge transfer agent used in the organic photoreceptor has not only the sensitivity and other characteristics as a photoreceptor, but also a chemical stability that withstands light, ozone, and electrical loads. Stability and durability are required so that the sensitivity does not decrease even after repeated use or long-term use. An object of the present invention is to provide a novel acenaphthene compound useful as a charge transporting agent that can realize an electrophotographic photoreceptor having high sensitivity and high durability, which satisfies the characteristics of the photoreceptor, and an electrophotographic photoreceptor using the compound. To provide.

[0007]

According to the present invention, an acenaphthene compound represented by the following general formula (1) and a photosensitive layer containing the compound on a conductive support are used for electrophotography. A photoreceptor is provided.

[0008]

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[Wherein Ar ₁ and Ar ₃ represent an aryl group which may have a substituent, and Ar ₂ represents a phenylene group, a naphthylene group, a biphenylene group or an anthrylene group which may have a substituent. In the formula, X represents an alkyl group which may have a substituent or an aryl group which may have a substituent. ]

In the present invention, the acenaphthene compound represented by the above general formula (1) used as a charge transport agent is a novel compound, and these compounds are, for example, 5-
(N, N-diphenylamino) acenaphthene derivative is formylated and synthesized by a hydrazone reaction with a corresponding hydrazine compound. Formylation is Vilsmei
The general method is by the er reaction. For example, the following general formula (2)

[0011]

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[In the formula, Ar ₁ and Ar ₂ have the same meaning as in the general formula (1). ] 5- (N, N- represented by
The diphenylamino) acenaphthene derivative is formylated with N, N-dimethylformamide, phosphorus oxychloride and the like to give a compound represented by the following general formula (3):

[0013]

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[In the formula, Ar ₁ and Ar ₂ have the same meaning as in the general formula (1). ] The aldehyde compound represented by this is obtained. Next, the following general formula (4) is added to the aldehyde compound.

[0015]

[Chemical 6]

[In the formula, Ar ₃ and X have the same meaning as in the general formula (1). ] It reacts with the hydrazine compound represented by this, and the acenaphthene compound of this invention represented by the said General formula (1) is obtained.

The condensation reaction between the aldehyde compound and the hydrazine compound described above is a reaction known as a hydrazone-forming reaction and is preferably carried out in the presence of an acidic catalyst. In this case, hydrochloric acid, acetic acid or the like is used as the acidic catalyst. As the solvent, methyl alcohol, ethyl alcohol, t-butyl alcohol, toluene, tetrahydrofuran, dioxane, dimethyl sulfoxide, N, N
-Dimethylformamide or the like is used. The reaction temperature is usually room temperature to 100 ° C. The hydrazine compound represented by the general formula (4) used as a raw material in the present invention is easily synthesized by nitrosating a corresponding amine compound and then reducing the compound.

In the general formula (1), Ar ₁ and A
When r ₃ is an aryl group, the aryl group may be a phenyl group, a naphthyl group, a biphenylyl group, an anthryl group,
Examples thereof include a phenanthryl group and a pyrenyl group.
When Ar ₁ and Ar ₃ are aryl groups having a substituent, the substituents are a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, and 5 carbon atoms.
6 cycloalkyl group, benzyl group, phenyl group, halogen atom or lower alkylamino group having 1 to 4 carbon atoms, etc., and when the substituent is benzyl group or phenyl group, lower group having 1 to 4 carbon atoms. It may be further substituted with an alkyl group, a lower alkoxy group having 1 to 4 carbon atoms, or a halogen atom. Examples of the substituent such as a phenylene group which may have a substituent of Ar ₂ include a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, and a cycloalkyl having 5 to 6 carbon atoms. Examples thereof include an alkyl group, a benzyl group, a phenyl group and a halogen atom. When the substituent is a benzyl group or a phenyl group, a lower alkyl group having 1 to 4 carbon atoms or a lower alkoxy group having 1 to 4 carbon atoms or It may be further substituted with a halogen atom.

Preferred specific examples of the compound according to the present invention which can be used as the charge transfer agent are as follows.

Compound No. 1

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Compound No. 2

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Compound No. 3

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Compound No. 4

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Compound No. 5

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Compound No. 6

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Compound No. 7

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Compound No. 8

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Compound No. 9

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Compound No. 10

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Compound No. 11

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Compound No. 12

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Compound No. 13

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Compound No. 14

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Compound No. Fifteen

[Chemical 21]

Compound No. 16

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Compound No. 17

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The electrophotographic photoreceptor of the present invention has a photosensitive layer containing one or more of the above-mentioned acenaphthene compounds. There are various forms of the photosensitive layer, and any of them may be used as the photosensitive layer of the electrophotographic photosensitive member of the present invention. As a typical example, the photoreceptor is shown in FIGS.

The photoconductor of FIG. 1 comprises a conductive support 1 and a photoconductive layer 2 comprising an acenaphthene compound, a sensitizing dye and a binder resin. The photoreceptor of FIG. 2 has a photosensitive layer 2 in which a charge generating substance 4 is dispersed in a charge transport medium 3 composed of an acenaphthene compound and a binder resin on a conductive support 1.
1 is provided. In the present photoreceptor, the charge generation substance absorbs light to generate charge carriers, which are transported by the charge transport medium. In this case, it is desirable that the charge transporting material is transparent to light that generates charge carriers. The acenaphthene compound satisfies the condition that the absorption wavelength region does not overlap with the charge generating substance, with only a slight absorption in the low wavelength region from the ultraviolet to the visible region.

In the photoreceptor of FIG. 3, a photosensitive layer 22 composed of a charge-generating layer 5 mainly composed of a charge-generating substance 4 and a charge-transporting layer 3 composed of an acenaphthene compound and a binder resin is formed on a conductive support 1. It is provided. In the present photoreceptor, light transmitted through the charge transport layer 3 reaches the charge generation layer 5 and is absorbed by the charge generation substance 4 to generate charge carriers. The charge carriers are injected into the charge transport layer 3 and transported. The photosensitive member of FIG. 4 is provided with a photosensitive layer 23 in which the order of stacking the charge generation layer 5 and the charge transport layer 3 of the photosensitive member of FIG. 3 is reversed. Generation and transport of charge carriers can be explained by the same mechanism as described above. The photoreceptor of FIG. 5 has a photosensitive layer 24 in which a protective layer 6 is further laminated on the charge generation layer 5 of the photoreceptor of FIG. 4 for the purpose of improving mechanical strength.
Is provided.

The photoreceptor of the present invention as exemplified above is manufactured by a conventional method. For example, the above general formula (1)
Prepared by dissolving the acenaphthene compound represented by in a suitable solvent together with a binder resin, and adding a charge generating substance, a sensitizing dye, an electron-withdrawing compound or a plasticizer, a pigment, and other additives as necessary. It can be manufactured by applying a coating liquid of the above onto a conductive support and drying it to form a photosensitive layer of several μm to several tens μm. In the case of a photosensitive layer composed of two layers of a charge generation layer and a charge transport layer, the above-mentioned coating solution is applied onto the charge generation layer, or the charge generation layer is applied onto the charge transport layer obtained by applying the above-mentioned coating solution. It can be manufactured by forming. Further, the photoreceptor thus manufactured may be provided with an adhesive layer, an intermediate layer, and a barrier layer, if necessary.

As the solvent for preparing the coating solution, tetrahydrofuran, 1,4-dioxane, methyl ethyl ketone,
Examples thereof include polar organic solvents such as cyclohexanone, acetonitrile, N, N-dimethylformamide and ethyl acetate, aromatic organic solvents such as toluene and xylene, and chlorinated hydrocarbon solvents such as dichloromethane and dichloroethane. A solvent having a high solubility in the acenaphthene compound and the binder resin is preferably used.

Examples of the sensitizing dyes include triarylmethane dyes such as methyl violet, brilliant green, crystal violet and acid violet, xanthene dyes such as rhodamine B, eosin S and rose bengal, and thiazine dyes such as methylene blue. Examples thereof include pyrylium dyes such as benzopyrylium salts, thiapyrylium dyes, and cyanine dyes.

Examples of the electron-withdrawing compound which forms a charge transfer complex with the acenaphthene compound include chloranil, 2,3-dichloro-1,4-naphthoquinone, 1-nitroanthraquinone, 2-chloroanthraquinone and phenanthrenequinone. Quinones, aldehydes such as 4-nitrobenzaldehyde, 9-benzoylanthracene, indandione, 3,5-dinitrobenzophenone, 2,4,7-trinitrofluorenone, 2,4,4.
Ketones such as 5,7-tetranitrofluorenone, acid anhydrides such as phthalic anhydride and 4-chloronaphthalic anhydride,
Tetracyanoethylene, terephthalalmalenonitrile,
Cyano compounds such as 9-anthrylmethylidenemalenonitrile, 3-benzalphthalide, 3- (α-cyano-p-
Nitrobenzal) -4,5,6,7-tetrachlorophthalide and other phthalides.

Examples of the binder resin include polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, butadiene, polyvinyl acetal, polycarbonate, polyester, polyphenylene oxide, polyurethane, Examples thereof include various resins compatible with the acenaphthene compound, such as cellulose ester, phenoxy resin, silicon resin, and epoxy resin. The amount of the binder resin used is usually in the range of 0.4 to 10 times by weight, preferably 0.5 to 5 times by weight, with respect to the acenaphthene compound.

The photosensitive layer of the present invention may contain a well-known plasticizer for the purpose of improving film-forming property, flexibility and mechanical strength. Examples of the plasticizer include phthalic acid ester, phosphoric acid ester, chlorinated paraffin, methylnaphthalene, epoxy compound, chlorinated fatty acid ester and the like.

Further, as the conductive support on which the photosensitive layer is formed, the materials used in known electrophotographic photoreceptors can be used. For example, a metal drum such as aluminum, stainless steel or copper, a sheet or a laminate of these metals, a vapor deposition product, a metal powder, carbon black, copper iodide or a conductive substance such as a polymer electrolyte is applied together with an appropriate binder. Conductive treated plastic film,
Examples thereof include a plastic drum, paper, a paper tube, and a plastic film and a plastic drum which are made conductive by containing a conductive substance.

[0047]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described specifically with reference to examples. Parts in Examples are parts by weight.

Synthesis Example 1 (Synthesis of Compound No. 1) “Synthesis of 5- [N- (4-formylphenyl) -N-phenylamino] acenaphthene” 5- (N, N-diphenylamino) acenaphthene 32.
14 g (0.1 mol) was dissolved in 300 ml of N, N-dimethylformamide, and phosphorus oxychloride 22.7 was added at room temperature.
3 g (0.15 mol) was added dropwise over 30 minutes. 60
The temperature was raised to ° C and the mixture was stirred for 16 hours. 93% after reaction
45 g (1.05 mol) of sodium hydroxide was added to 100 parts of water.
The reaction solution was poured into the solution dissolved in 0 ml and stirred. The precipitated crystals were filtered, washed with water and methanol to give 5- [N
30.27 g (yield; 86.6%) of-(4-formylphenyl) -N-phenylamino] acenaphthene was obtained.

"4- [N- (acenaphthen-5-yl)
—N-Phenylamino] benzaldehyde Synthesis of N, N-diphenylhydrazone ”5- [N- (4-formylphenyl)-
N-phenylamino] acenaphthene 10.48 g (0.
03 mol) to N, N-dimethylformamide 150 m
Dissolve in 1 and add N, N-diphenylhydrazine hydrochloride (0.036 mol) at room temperature. Stirred at room temperature for 2 hours. After the reaction was completed, the system was cooled to 5 ° C or lower and 300 ml of methanol was added dropwise. Further, an aqueous solution prepared by diluting 3.6 ml of 28% ammonia water with 30 ml of water was added dropwise.
The precipitated crystals were filtered, washed with methanol, washed with water and dried. Column chromatography (carrier; silica gel, eluent; toluene: hexane = 1: 1)
3) and purified by 4- [N- (acenaphthen-5-yl) -N-phenylamino] benzaldehyde N, N
14.8 g of diphenylhydrazone (yield; 90.8
%, Melting point; 178.5-180.0 ° C.). The elemental analysis values were as shown below as C ₃₇ H ₂₉ N ₃ . Carbon: 86.24% (86.18%), Hydrogen: 5.53%
(5.67%), nitrogen: 8.22% (8.15%) (calculated values are shown in parentheses.) Characteristic fundamental wave number (c) of infrared absorption spectrum (KBr tablet method)
m ⁻¹ ) is 3028, 2914, 1587, 1487, ¹
It was 293 and 695 mag.

Synthesis Example 2 (Synthesis of Compound No. 6) “Synthesis of 4- [N- (acenaphthen-5-yl) -N-phenylamino] benzaldehyde N-methyl-N-phenylhydrazone” In Example 1 10.48 g of synthesized 5- [N- (4-formylphenyl) -N-phenylamino] acenaphthene
(0.03 mol) of N, N-dimethylformamide 1
After dissolving in 50 ml, at room temperature, 4.4 g (0.036 mol) of N-methyl-N-phenylhydrazine and 5 ml of glacial acetic acid were added. Stirred at room temperature for 2 hours. After the reaction was completed, the system was cooled to 5 ° C or lower and 300 ml of methanol was added dropwise. Further, 45 ml of water was added dropwise. The precipitated crystals were filtered, washed with methanol, washed with water and dried. This crystal was subjected to column chromatography (carrier; silica gel,
Eluent; toluene: hexane = 1: 3) to purify 4- [N- (acenaphthen-5-yl) -N-phenylamino] benzaldehyde N-methyl-N-phenylhydrazone 10.4 g (yield; 76 .6%, melting point; 15
7.0-158.5 ° C) was obtained. Elemental analysis value is C ₃₂ H ₂₇
It was as shown below as N ₃ . Carbon: 84.54%
(84.73%), hydrogen: 6.08% (6.00%),
Nitrogen: 9.37% (9.27%) (calculated value is shown in parentheses.) Characteristic fundamental number (c) of infrared absorption spectrum (KBr tablet method)
m ⁻¹ ) is 3020, 2914, 1589, 1491, ¹
It was 312, 748 mag.

Example 1 As a charge generating agent, the following chlorodian blue (charge generating agent No. 1)

[0052]

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1.5 parts of polyester resin (Byron 2
00, Toyobo Co., Ltd.) 8 wt% THF solution 18.5
In addition to the parts, the mixture was placed in an agate pot containing agate balls, and rotated by a planetary type fine pulverizer (made by Fritz Co.) for 1 hour to disperse. The resulting dispersion is deposited on an aluminum deposited P as a conductive support.
It was applied on an aluminum surface of the ET film using a wire bar and dried at 60 ° C. under normal pressure for 2 hours and further under reduced pressure for 2 hours to form a charge generation layer having a thickness of 0.3 μm. On the other hand, Compound No. 1 acenaphthene compound 1.
5 parts of polycarbonate resin (Panlite K-130
No. 0, Teijin Kasei Co., Ltd. 8 wt% dichloroethane solution (18.75 parts) was added and ultrasonic waves were applied to completely dissolve the acenaphthene compound. This solution was applied onto the charge generation layer with a wire bar and dried under normal pressure at 60 ° C. for 2 hours and further under reduced pressure for 2 hours to form a charge transport layer having a film thickness of 20 μm. 1 was produced. About this photoconductor Electrostatic copying paper tester (trade name "EPA-8100")
The sensitivity was measured using Kawaguchi Electric Co., Ltd. First, the photoreceptor is charged by a corona discharge of −6 kV in the dark, and then exposed to a white light of 3.0 lux, and the time (second) until the surface potential decreases to half of the initial surface potential is measured, The half-exposure amount E1 / 2 (lux · sec) was determined.
The initial surface potential of this photosensitive member was -865 V, and E1 / 2 was 1.02 lux.sec.

Examples 2 to 12 Photosensitive member No. 1 was carried out in the same manner as in Example 1 except that the charge generating agent and the charge transporting agent (acenaphthene compound) used in Example 1 were replaced with those shown in Table 1. 2-12 were produced.
The charge generating agent No. shown in Table 1 was used. 2-No. The structure of 4 is shown below.

Charge generating agent No. 2

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Charge Generating Agent No. 3

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Charge Generating Agent No. 4

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Photoreceptor No. Sensitivity was measured for 2 to 12 in the same manner as in Example 1. Table 2 shows the results.

[0059]

[Table 1]

[0060]

[Table 2]

Example 13 The charge transfer agent (acenaphthene compound) used in Example 1 was compound No. No. 1 acenaphthene compound and compound No. 1 6
Photoreceptor No. 1 was carried out in the same manner as in Example 1 except that the 1: 1 weight ratio mixture of the acenaphthene compound was used. 13 was produced. When the sensitivity of this photosensitive member was measured in the same manner as in Example 1, the initial surface potential was −861 V and E1 / 2 was 0.98 lux · second.

Example 14 As a charge generating agent, 1.5 parts of α-type titanyl phthalocyanine oxide (α-TiOPc) was added to a polyvinyl butyral resin (S-REC BX-L, manufactured by Sekisui Chemical Co., Ltd.) in an amount of 50 parts by weight in THF. In addition, 45 with ultrasonic disperser
Dispersed for minutes. The obtained dispersion is applied on an aluminum surface of an aluminum-deposited PET film as a conductive support using a wire bar, and dried at 60 ° C. under normal pressure for 2 hours and further under reduced pressure for 2 hours to obtain a film thickness of 0.2 μm. Was formed. On the other hand, Compound No. 1.5 parts of the acenaphthene compound of 1 is a polycarbonate resin (Panlite K-
1300, manufactured by Teijin Kasei Co., Ltd., was added to 18.75 parts of an 8 wt% dichloroethane solution, and ultrasonic waves were applied to completely dissolve the acenaphthene compound. This solution is applied onto the charge generation layer with a wire bar, and the temperature is maintained at 60 ° C. for 2 hours.
Further, it was dried under reduced pressure for 2 hours to form a charge transport layer having a film thickness of 20 μm. 14 was produced. About this photoconductor, an electrostatic copying paper testing device (trade name "EPA-8
100 ") was used to measure the sensitivity. First, the photoconductor is charged in a dark place by corona discharge of −6 kV, and then exposed to a monochromatic light of 800 nm with a light amount of 5.0 μW / cm ² , and the amount of energy until the surface potential is reduced to half of the initial surface potential. Then, the half-exposure dose E1 / 2 (μJ / cm ² ) was measured. The initial surface potential of this photoconductor is -930 V, and E
1/2 was 0.77 μJ / cm ² .

Example 15 The procedure of Example 14 was repeated except that X-type metal-free phthalocyanine was used in place of α-TiOPc as the charge generating agent. 15 were created. When the sensitivity of this photosensitive member was measured in the same manner as in Example 14, the initial surface potential was −932 V and E1 / 2 was 0.70 μJ / cm ² . Example 16 As a charge generating agent, the following trisazo compound was used instead of α-TiOPc.

[0064]

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The same procedure as in Example 14 was carried out except that No. 16 were produced. Example 14
When the sensitivity was measured in the same manner as in 1., the initial surface potential was -987V and E1 / 2 was 0.60 μJ / cm ² .

Example 17 The following thiapyrylium salt as a charge generating agent

[0067]

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0.1 part, Compound No.
10 parts of the acenaphthene compound 3 of No. 3 was added to 125 parts of an 8 wt% dichloroethane solution of a polycarbonate resin (Panlite K-1300, manufactured by Teijin Chemicals Ltd.), and ultrasonic waves were applied to completely dissolve the thiapyrylium salt and the acenaphthene compound. . This solution is used as a conductive support for aluminum-deposited PE.
It was coated on the aluminum surface of the T film using a wire bar and dried under normal pressure at 60 ° C. for 2 hours and further under reduced pressure for 2 hours to form a photosensitive layer having a film thickness of 20 μm. 1
7 was produced. The sensitivity of this photoconductor was measured using an electrostatic copying paper tester (trade name "EPA-8100"). First, the photoreceptor is charged by +7 kV corona discharge in the dark and then exposed to 3.0 lux white light, and the time (seconds) until the surface potential decreases to half of the initial surface potential is measured. Exposure E1 / 2 (Looks / second)
I asked. The initial surface potential of this photoconductor is + 842V,
E1 / 2 was 1.7 lux · sec.

Example 18 The charge transporting agent coating liquid used in Example 1 was applied to aluminum vapor-deposited PE.
It was applied on the aluminum surface of the T film using a wire bar and dried under normal pressure at 60 ° C. for 2 hours and further under reduced pressure for 2 hours to form a charge transport layer having a film thickness of 10 μm. On the other hand, the same disazo compound as that used in Example 2 as the charge generating agent 3.
0 part was added to 18.5 parts of an 8 wt% THF solution of a polyester resin (Vylon 200, manufactured by Toyobo Co., Ltd.), placed in an agate pot containing agate balls, and a planetary type fine pulverizer (made by Fritz) for 1 hour. Rotated and dispersed. To this dispersion, 200 parts of THF was added, and mixed by stirring to obtain a coating liquid. This coating solution was applied onto the above charge transport layer by spraying and dried under normal pressure at 60 ° C. for 2 hours and further under reduced pressure for 2 hours to form a charge generation layer having a thickness of 0.5 μm. Further, a solution prepared by dissolving an alcohol-soluble polyamide resin in isopropanol is spray-coated on the charge generation layer, and the film thickness is 0.5 μm under normal pressure at 60 ° C. for 2 hours and further under reduced pressure for 2 hours.
Of the photoconductor No. 18 were produced. The sensitivity of this photoreceptor was measured in the same manner as in Example 17. The initial surface potential of this photoreceptor is + 830V,
E1 / 2 was 1.3 lux · sec.

Comparative Example 1 Compound No. used in Example 1 The following compounds instead of the acenaphthene compound of No. 1

[0071]

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A comparative photoconductor was prepared in the same manner as in Example 1 except that was used. The sensitivity of this photoreceptor was measured in the same manner as in Example 1. The initial surface potential of this photoconductor is -82.
At 5 V, E1 / 2 was 1.31 lux.sec.

[0073]

INDUSTRIAL APPLICABILITY The novel acenaphthene compound of the present invention has an excellent charge transporting ability and can be widely used as a charge transporting material. Further, the electrophotographic photoreceptor of the present invention having a photosensitive layer containing these compounds on a conductive support exhibits excellent photoreceptor characteristics, and has the advantage that it can be widely used as an electrophotographic photoreceptor. Have

[Brief description of drawings]

FIG. 1 is a sectional view of a single-layer photoconductor for electrophotography.

FIG. 2 is a cross-sectional view of a single-layer photoconductor for electrophotography in which a charge generating substance is dispersed.

FIG. 3 is a cross-sectional view of an electrophotographic photoconductor in which a charge generation layer and a charge transport layer are laminated on a conductive support in this order.

FIG. 4 is a cross-sectional view of an electrophotographic photoconductor in which a charge transport layer and a charge generation layer are laminated in this order on a conductive support.

FIG. 5 is a cross-sectional view of an electrophotographic photoconductor provided with a protective layer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive support 2, 21, 22, 23, 24 Photosensitive layer 3 Charge transport medium, charge transport layer 4 Charge generating substance 5 Charge generating layer 6 Protective layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Chieko Inayoshi 45 Miyukigaoka, Tsukuba, Ibaraki Hodogaya Chemical Industry Co., Ltd. Tsukuba Research Institute

Claims (2)

[Claims] 1. The following general formula (1): [Wherein Ar ₁ and Ar ₃ represent an aryl group which may have a substituent, and Ar ₂ represents a phenylene group, a naphthylene group, a biphenylene group which may have a substituent, or an anthrylene group, and X Represents an alkyl group which may have a substituent or an aryl group which may have a substituent. ] The acenaphthene compound represented by these. 2. The following general formula (1): embedded image on a conductive support. [Wherein Ar ₁ and Ar ₃ represent an aryl group which may have a substituent, and Ar ₂ represents a phenylene group, a naphthylene group, a biphenylene group which may have a substituent, or an anthrylene group, and X Represents an alkyl group which may have a substituent or an aryl group which may have a substituent. ] It has a photosensitive layer containing the acenaphthene compound represented by these, The photoreceptor for electrophotography characterized by the above-mentioned.