JPH056011A - Photosensitive body - Google Patents

Abstract

PURPOSE:To obtain the photosensitive body which has excellent transferability and lessens the fatigue deterioration and increase of a residual potential particularly after repetitive use by providing a photosensitive layer contg. a specific distilyl compd. CONSTITUTION:This photosensitive body has the photosensitive layer contg. the distilyl compd. expressed by formula I on a conductive base. In the formula I, R1, R2 respectively independently denote a hydrogen atom, alkyl group, alkoxy group or halogen atom; Ar1 to Ar4 respectively independently denote a hydrogen atom, an alkyl group, aryl group, heterocyclic group, etc., which respectively may have a substituent. The case where at least either of Ar1, Ar2 is a hydrogen atom and at least either of Ar3, Ar4 is a hydrogen atom is excluded. Z is a residual group forming a 5-membered ring or 6-membered ring by bonding to a benzene ring and a nitrogen atom and may have a substituent. This compd. is asymmetrical around the nitrogen atom and stereoscopic faults are decreased in this way. Crystallization is suppressed in a binder resin and the good compatibility with the binder resin is exhibited.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photoreceptor having a photosensitive layer containing a novel distyryl compound.

[0002]

2. Description of the Related Art Conventionally, as a photoreceptor, one having a photosensitive layer containing an inorganic photoconductive substance as a main component and one having a photosensitive layer containing an organic photoconductive substance as a main component are known. Inorganic materials have drawbacks such as high toxicity, poor film-forming property, lack of flexibility, and high manufacturing cost.

On the other hand, research using organic photoconductive substances typified by polyvinylcarbazole compounds in the photosensitive layer of the photoconductor has progressed and has already been put to practical use. In general, an organic photoconductive substance is better in transparency, lighter in weight and excellent in film forming property than an inorganic photoconductive substance, but inferior in terms of sensitivity, durability and stability due to environmental changes. Therefore, the charge generation function and the charge transport function in the photoconductive function are separately assigned to different substances with high sensitivity and repeated stability,
A function-separated photoreceptor having excellent durability has been developed.

The above-mentioned function-separated type photoreceptor has a photosensitive layer in which a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material are laminated, or a charge generation material and a charge transport layer. Some have a photosensitive layer containing a material in a binder resin. In recent years, for example, JP-A-60-175052 and JP-A-62-1
Japanese Patent No. 20346 discloses a photoconductor containing a styryl compound having a symmetrical structure around a nitrogen atom represented by the following general formula.

[0005]

[Chemical 2]

(In the formula, R _{1 to} R ₄ and Ar represent those described in the above-mentioned respective publications).
No. 7055 discloses a styryl compound represented by the following general formula.

[0007]

[Chemical 3]

(In the formula, Ar ₁ and Ar _{2 each} represent an aromatic hydrocarbon or a heterocyclic residue, R ₁ and R ₂ are independently a hydrogen atom,
It represents a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a dialkylamino group, a diarylamino group, a diaalkylamino group, a cyano group or a nitro group. A
May have a substituent on a benzene ring or a residue which is bonded to a nitrogen atom to form a 5- or 6-membered ring. )

[0009]

However, in the above-mentioned photosensitive member, by repeating the image forming process such as charging, exposure and charge elimination, ozone generated at the time of charging and a laser irradiated with high brightness are obtained. As a result, the charge transport material is deteriorated, and there is a problem that an image bleeding occurs due to a decrease in charging potential or an increase in residual potential. Further, the distyryl compound having a symmetrical structure as described in the above publication has a large molecular size, has a low compatibility with a binder resin due to steric hindrance, and has a drawback that crystals are likely to precipitate.

Therefore, an object of the present invention is to eliminate the above-mentioned problems and to contain a distyryl compound excellent in compatibility with a binder resin and charge transporting ability, and having high sensitivity, excellent charging ability and ozone resistance, and particularly repeated It is an object of the present invention to provide a photoreceptor having less fatigue deterioration with use.

[0011]

The present invention provides a photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains a distyryl compound represented by the following general formula (I). To do.

[0012]

[Chemical 4]

(Wherein R ₁ and R ₂ are independently a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom, Ar ₁ ,
Ar ₂ , Ar ₃ and Ar ₄ each independently represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group, a heterocyclic group or a condensed polycyclic group. However, the case where at least one of Ar ₁ and Ar ₂ is a hydrogen atom and at least one of Ar ₃ and Ar ₄ is a hydrogen atom is excluded. Z is a benzene ring or a residue which is bonded to a nitrogen atom to form a 5- or 6-membered ring and may have a substituent. ) A method for producing the distyryl compound of the general formula (I) used in the present invention is described below.

The distyryl compound of the present invention is, for example, an aldehyde compound represented by the following general formula (II)

[0015]

[Chemical 5]

(In the formula, R ₁ , R ₂ and Z have the same meaning as (I).)
It can be synthesized by condensing a phosphorus compound represented by the following general formula (III-a) or (III-b).

[0017]

[Chemical 6]

(In the formula, Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are synonymous with (I). X is

[0019]

[Equation 1]

A trialkyl group or triarylphosphonium group represented by or a dialkyl group or diaryl phosphite group represented by PO (OR ₄ ) ₂ is shown. However, in the formula, Y represents a halogen atom, and R ₃ and R ₄ each represent an alkyl group or an aryl group. ) Further, the compound represented by the general formula (I) is condensed with the compounds represented by the following general formulas (III-a) and (IV), or is represented by the general formula (III-b) and (V). It can also be synthesized by condensing the represented compound.

[0021]

[Chemical 7]

(Where Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , R ₁ ,
R ₂ and Z have the same meaning as (I), and X has the same meaning as (III-a). As the reaction solvent in the above method, for example, hydrocarbons, alcohols and ethers are preferable, and methanol, ethanol, iso-propyl alcohol, butanol, 2-methoxyethanol, 1,2-dimethoxyethane, bis (2
-Methoxyethyl) ether, dioxane, tetrahydrofuran, toluene, xylene, dimethylsulfoxide, N, N-dimethylformamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone. Among them, polar solvents such as N, N-dimethylformamide and dimethyl sulfoxide are preferable.

As the condensing material, caustic soda, caustic potash, sodium amide, sodium hydrogen, and alcoholates such as sodium methylate and potassium ter-butoxide are used.

The reaction temperature is about 0 ° C to about 100 ° C, preferably 10 ° C to 80 ° C, and can be selected over a wide range.

All of the distyryl compounds represented by the above general formula (I) are structurally characterized in that they are asymmetrical with respect to the nitrogen atom. Since the crystallization can be suppressed in (1), it exhibits good compatibility with the binder resin. Further, the distyryl compound has a cyclic structure, and this structure is particularly effective for ozone deterioration.

The general formulas used for the photoreceptor of the present invention are as follows.
Specific examples of the distyryl compound represented by (I) are shown below, but the invention is not limited thereto.

[0027]

[Chemical 8]

[0028]

[Chemical 9]

[0029]

[Chemical 10]

[0030]

[Chemical 11]

[0031]

[Chemical formula 12]

[0032]

[Chemical 13]

[0033]

[Chemical 14]

[0034]

[Chemical 15]

[0035]

[Chemical 16]

[0036]

[Chemical 17]

[0037]

[Chemical 18]

The distyryl compound, which is a photoconductive material, acts as a charge transport material and transports charge carriers generated by absorbing light very efficiently.

By forming a photosensitive layer containing one or more of the above distyryl compounds on a conductive support, it is possible to provide a photosensitive material of the present invention having high sensitivity and excellent ozone resistance. As the form, for example, FIG.
An example is shown in FIG.

For example, a conductive support 1 as shown in FIG.
A function-separated type laminated photoreceptor in which a charge generation layer 5 containing a charge generation material 2 and a charge transport layer 6 containing a charge transport material 3 are laminated in this order, or a conductive material as shown in FIG. A functionally separated photoreceptor in which a charge transporting layer 6 containing a charge transporting material 3 and a charge generating layer 5 containing a charge generating material 2 are laminated in this order on a conductive support 1. A single-layer type photoreceptor in which the photosensitive layer formed on the conductive support 1 as shown in FIG. 3 is formed by mixing the charge generating material 2 and the charge transporting material 3 together with a binder resin to form the photosensitive layer 4. Further, as shown in FIG. 4, a surface protective layer 7 is provided on the surface of the photosensitive member of FIG. 1, and an intermediate layer 8 is provided between the conductive support 1 and the photosensitive layer 4 as shown in FIG. It may be one.

First, the case of producing a laminated photoreceptor as shown in FIG. 1 as the photoreceptor of the present invention will be described. In this case, the charge generating material is vacuum-deposited on the conductive support or is dissolved in a solvent such as amine and applied, or the pigment is dissolved in a suitable solvent or a binder resin if necessary. The coating solution prepared by dispersing in a solution is applied and dried to form a charge generation layer.
It is prepared by coating and drying a solution containing the distyryl compound of the present invention represented by (I) and a binder resin to form a charge transport layer. In the case of vacuum vapor deposition, phthalocyanines such as metal-free phthalocyanine, titanyl phthalocyanine, and aluminum chlorophthalocyanine are used. When dispersed, for example, a bisazo pigment is used. At this time, the proportion of the distyryl compound in the charge transport layer is 0.02 to 2 parts by weight with respect to 1 part by weight of the binder resin,
It is preferably 0.03 to 1.3 parts by weight, and the film thickness of the charge transport layer is 3 to 30 μm, preferably 5 to 20 μm. The thickness of the charge generation layer is 4 μm or less, preferably 2 μm or less.

It has been confirmed that such a function-separated type laminated photoconductor has a sufficient charge holding ability, the dark decay rate is so small that there is no problem in practical use, and the sensitivity is also excellent. Further, the half-exposure value is sufficiently smaller than that of the single-layer type photoreceptor, and the distyryl compound is particularly effective as a charge transport material for a laminated photoreceptor.

A case where a single-layer type photoconductor as shown in FIG. 3 is manufactured as the photoconductor in the present invention will be described.

In this case, fine particles of the charge generating material are dispersed in a solution in which a distyryl compound and a binder resin are dissolved, and this is coated and dried on a conductive support to form a photosensitive layer to prepare a photosensitive member. .. At this time, the mixing ratio of the distyryl compound in the photosensitive layer is 0.01 to 2 parts by weight, preferably 0.05 to 5 parts by weight with respect to 1 part by weight of the binder resin in the photosensitive layer.
1 part by weight is desirable. When the amount of the charge generating material is small with respect to the binder resin in the photosensitive layer, sufficient sensitivity cannot be obtained, and when the amount is large, problems such as poor charging and weak mechanical strength of the photosensitive layer occur. Therefore, 0.01 to 2 parts by weight, preferably 0.2 to 1 part by weight per 1 part by weight of the binder resin in the photosensitive layer.
It is preferable to add 2 parts by weight. The thickness of the photosensitive layer is usually 3 to 30 μm, preferably 5 to 20 μm.

The single-layer type photoreceptor as described above has a sufficient charge holding ability as compared with the conventional one, and the dark attenuation rate is small enough to cause no problem in practical use, and the sensitivity is high.

The photoreceptor of the present invention may be provided with an intermediate layer as shown in FIG. 5, whereby the adhesion is improved, the coatability is improved, the support is protected, and the support side is provided. The charge injection property to the photosensitive layer can be improved.

Suitable materials for the intermediate layer are polyimide, polyamide, nitrocellulose polyvinyl butyral, polyvinyl alcohol, aluminum oxide and the like, and the film thickness is preferably 1 μm or less.

Further, the photoreceptor of the present invention may be provided with a surface protective layer. As a material used for the surface protective layer, a polymer such as an acrylic resin, a polyaryl resin, a polycarbonate resin, or a urethane resin is directly used,
Alternatively, a material in which a low resistance compound such as tin oxide or indium oxide is dispersed is suitable.

It is also possible to use organic plasma polymerized membranes. The organic plasma polymerized film is appropriately oxygen,
It may contain nitrogen, halogen, and atoms of Group 3 and Group 5 of the periodic table.

As the conductive support used in the photoconductor of the present invention, a sheet or drum of copper, aluminum, iron, nickel or the like is used. Also, these metals are vacuum-deposited or electroless plated on a plastic film, or a layer of a conductive compound such as a conductive polymer, indium oxide or tin oxide is similarly formed on a support such as paper or a plastic film. It is provided by coating or vapor deposition.

Examples of the charge generating material used in the photoreceptor of the present invention include bisazo pigments, triarylmethane dyes, thiazine dyes, oxazine dyes, xanthene dyes, cyanine dyes, styryl dyes, pyrylium. Dyes, azo dyes, quinacdrine dyes, indigo pigments, perylene pigments, polycyclic quinone pigments, bisbenzimidazole pigments, indathlon pigments, squarylium pigments, phthalocyanine pigments, and other organic substances, and selenium. Inorganic substances such as selenium / tellurium, selenium / arsenic, cadmium sulfide, and amorphous silicon can be used. In addition, any material can be used as long as it absorbs light and generates charge carriers with extremely high efficiency.

The binder resin used in the production of the above-mentioned photosensitive member is electrically insulating, and when measured alone, the binder resin is 1 × 10 ^12.
It is desirable to have a volume resistance of Ω · cm or more. For example, a binder such as a thermoplastic resin, a thermosetting resin, a photocurable resin, or a photoconductive resin known per se can be used. Specifically, saturated polyester resin, polyamide resin, acrylic resin, ethylene-vinyl acetate resin, ion-crosslinked olefin copolymer (ionomer), styrene-butadiene block copolymer, polycarbonate, vinyl chloride-vinyl acetate copolymer, Cellulose ester,
Thermoplastic resin such as polyimide and styrene resin; thermosetting resin such as epoxy resin, urethane resin, silicone resin, phenol resin, melamine resin, xylene resin, alkyd resin and thermosetting acrylic resin; photocurable resin; polyvinyl carbazole, Examples thereof include photoconductive resins such as polyvinylpyrene, polyvinylanthracene, and polyvinylpyrrole, and these binder resins may be used alone or in combination of two or more kinds.

When the charge transporting material is a polymer charge transporting material which itself can be used as a binder, other binder resin may not be used.

The photoreceptor of the present invention includes a binder resin, a plasticizer such as halogenated paraffin, polychlorinated biphenyl, dimethylnaphthalene, dibutylphthalate, and O-terphenyl, chloranil, tetracyanoethylene, 2,4,7-.
Electron withdrawing sensitizers such as trinitrofluorenone, 5,6-dicyanobenzoquinone, tetracyanoquinodimethane, tetrachlorophthalic anhydride, 3,5-dinitrobenzoic acid, methyl violet, rhodamine B, cyanine dye, pyrylium salt, A sensitizer such as thiapyrylium salt may be used.

[0055]

[Synthesis Example] The method for synthesizing the distyryl compound represented by the above compound example (3) is shown below.

The following formula:

[0057]

[Chemical 19]

3.39 g of an aldehyde compound represented by
And the following formula:

[0059]

[Chemical 20]

3.04 g of a phosphonate compound represented by
Was dissolved in 70 ml of dimethylformamide. While cooling the obtained solution to 5 ° C. or lower, a suspension containing 1.5 g of potassium ter-butoxide in 70 ml of dimethylformamide was added dropwise, and the mixture was stirred at room temperature for 8 hours and then left overnight. The obtained mixture was barged in 900 ml of ice water and then neutralized with dilute hydrochloric acid. After about 1 hour, the precipitated crystal was filtered, the filtered product was washed with water and recrystallized with acetonitrile twice to obtain 3.2 g of yellow crystal (yield 65%).

The results of elemental analysis are as follows.

[0062]

[Table 1]

[0063]

EXAMPLES The distyryl compounds of the present invention used in the following examples were synthesized by the above-mentioned synthesis examples or a method similar thereto.

Example 1

[0065]

[Chemical 21]

0.45 parts by weight of the disazo compound represented by the general formula (VI), polyester resin (Vylon 200,
0.45 parts by weight of cyclohexanone 5 manufactured by Toyobo Co., Ltd.
It was dispersed by a sand mill together with 0 part by weight. The resulting dispersion of the disazo compound was applied on a 100 μm thick aluminized mylar using a film applicator so that the dry film thickness was 0.3 g / m ^2, and then dried to form a charge generation layer. On top of this, 50 parts by weight of distyryl compound (1) and polycarbonate (Panlite K-130
0, Teijin Kasei Co., Ltd.) 50 parts by weight dissolved in 400 parts by weight of 1,4-dioxane was applied to a dry film thickness of 16 μm and dried to form a charge transport layer,
A photoreceptor having a photosensitive layer composed of two layers was produced. The thus prepared photoconductor is incorporated into a commercially available electrophotographic copying machine (EP-450Z manufactured by Minolta Camera Co., Ltd.) to obtain -6 Kv.
Of the initial surface potential V ₀ (v),
Exposure amount necessary for the surface potential to be attenuated to half of the initial surface potential (hereinafter, half exposure amount) E _1/2 (Lux · sec), the attenuation rate of the initial potential when left in the dark for 1 second DDR ₁ ( %) Was measured. The results are shown in Table 2.

Examples 2 to 4 Example 1 except that the distyryl compounds (2), (3) and (4) were used in place of the distyryl compound (1) used in Example 1.
Three types of laminated photoconductors were produced in the same manner as in. For each of the photoconductors, V ₀ , E _1/2 and D were obtained in the same manner as in Example 1.
DR ₁ was measured and the results are shown in Table 2.

Example 5

[0069]

[Chemical formula 22]

0.45 parts by weight of the disazo compound represented by the general formula (VII), polystyrene resin (molecular weight 4000
0) 0.45 parts by weight was dispersed by a sand mill together with 50 parts by weight of cyclohexanone. The resulting dispersion of disazo compound was dried on aluminized mylar having a thickness of 100 μm using a film applicator to give a dry film thickness of 0.3 g.
/ M ² and then dried to form a charge generation layer. 50 parts by weight of a distyryl compound (5) and a polyarylate resin (U-100, manufactured by Unitika Ltd.)
A solution having 0 parts by weight dissolved in 400 parts by weight of 1,4-dioxane is applied to a dry film thickness of 20 μm and dried to form a charge transport layer, and a photosensitive layer having two photosensitive layers is formed. The body was made. V ₀ , E _1/2 and DDR ₁ of this photoconductor were measured in the same manner as in Example 1, and the results are shown in Table 2.

Examples 6 to 8 Example 1 except that the distyryl compounds (6), (7) and (8) were used in place of the distyryl compound (5) used in Example 5.
Three types of laminated photoconductors were produced in the same manner as in. For each of the photoconductors, V ₀ , E _1/2 and D were obtained in the same manner as in Example 1.
DR ₁ was measured and the results are shown in Table 2.

Example 9

[0073]

[Chemical formula 23]

0.45 parts by weight of a polycyclic quinone pigment represented by the above general formula (VIII), polycarbonate (K-1300,
Teijin Kasei Co., Ltd.) 0.45 parts by weight of dichloroethane 50
It was dispersed with a sand mill together with parts by weight. The resulting polycyclic quinone pigment dispersion was applied onto a 100 μm thick aluminized mylar using a film applicator to a dry film thickness of 0.4 g / m ² and then dried to form a charge generation layer. Formed. On this, 60 parts by weight of distyryl compound (9) and polyarylate resin (U-100, Unitika
Co., Ltd.) A solution of 50 parts by weight dissolved in 400 parts by weight of 1,4-dioxane is applied so as to have a dry film thickness of 18 μm and dried to form a charge transport layer, which is composed of two layers. A photoreceptor having a photosensitive layer was prepared. V ₀ , E _1/2 and DDR ₁ of this photoconductor were measured in the same manner as in Example 1, and the results are shown in Table 2. Further, as for the above-mentioned photoreceptor, a commercially available electrophotographic copying machine (EP- manufactured by Minolta Camera Co., Ltd.) is used.
350Z) was repeatedly photographed during negative charging. 1
Even after the actual shooting of 000 sheets, the gradation is excellent in the final image as well as in the initial stage, and there is no sensitivity change and a clear image can be obtained.
It was confirmed that the photoreceptor of the present invention is stable in repeatability.

Examples 10 to 11 Two types of laminated photoconductors were prepared in the same manner as in Example 9 except that the distyryl compounds (11) and (13) were used in place of the distyryl compound (9) used in Example 9. Was produced. For each of the photoconductors, V ₀ , E _1/2 and DD were obtained in the same manner as in Example 1.
R ₁ was measured and the results are shown in Table 2.

Example 12

[0077]

[Chemical formula 24]

0.45 part by weight of the perylene pigment represented by the general formula (IX) and 0.45 part by weight of butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) together with 50 parts by weight of dichloroethane were subjected to sand milling. Dispersed. The resulting dispersion of the perylene pigment was applied onto a 100 μm thick aluminized mylar using a film applicator so that the dry film thickness was 0.4 g / m ^2, and then dried to form a charge generation layer. .. A solution obtained by dissolving 50 parts by weight of the distyryl compound (15) and 50 parts by weight of a polycarbonate resin (PC-Z, Mitsubishi Gas Chemical Co., Inc.) in 400 parts by weight of 1,4-dioxane was dried to a thickness of 18 μm. The coating liquid was applied as described above and dried to form a charge transport layer, to prepare a photoreceptor having a photosensitive layer composed of two layers. V ₀ , E _1/2 and DDR ₁ of this photoconductor were measured in the same manner as in Example 1, and the results are shown in Table 2.

Examples 13 to 14 Two types of laminated photoconductors were prepared in the same manner as in Example 12 except that the distyryl compounds (16) and (21) were used instead of the distyryl compound (15) used in Example 12. Was produced. For each of the photoconductors, V ₀ in the same manner as in Example 1,
E _1/2 and DDR ₁ were measured and the results are shown in Table 2.

Example 15 0.45 part by weight of a titanyl phthalocyanine pigment and 0.45 part by weight of butyral resin (PC-Z, manufactured by Mitsubishi Gas Chemical Co., Inc.) were dispersed in a sand mill together with 50 parts by weight of dichloroethane. The resulting dispersion liquid of the titanyl phthalocyanine pigment was applied on aluminized mylar having a thickness of 100 μm using a film applicator so that the dry film thickness was 0.3 g / m ^2, and then dried to form a charge generation layer. .. 50 parts by weight of a distyryl compound (22) and a polycarbonate resin (PC-Z, manufactured by Mitsubishi Gas Chemical Co., Inc.) 50
A photoconductor having a photosensitive layer composed of two layers, which is prepared by coating a solution in which 400 parts by weight of 1,4-dioxane is mixed to a dry film thickness of 18 μm and drying the solution to form a charge transport layer. Was produced. V ₀ , E _1/2 and DDR ₁ of this photoreceptor were measured in the same manner as in Example 1 and the results are shown in Table 2.
Shown in.

Examples 16 to 17 Two kinds of laminated photoreceptors were prepared in the same manner as in Example 15 except that the distyryl compounds (23) and (24) were used instead of the distyryl compound (22) used in Example 15. Was produced. For each of the photoconductors, V ₀ in the same manner as in Example 1,
E _1/2 and DDR ₁ were measured and the results are shown in Table 2.

Example 18 0.45 parts by weight of copper phthalocyanine and 0.2 parts by weight of tetranitrocopper phthalocyanine were dissolved in 500 parts by weight of 98% concentrated sulfuric acid with sufficient stirring. This was mixed with 5000 parts by weight of water to deposit a charge generating material composition of copper phthalocyanine and tetranitrocopper phthalocyanine, filtered, washed with water, and dried at 120 ° C. under reduced pressure. 10 parts by weight of the photoconductive composition thus obtained was used as a thermosetting acrylic resin (Acridic A-405, Dainippon Ink
22.5 parts by weight, melamine resin (Super Beckamine J820, Dainippon Ink Co., Ltd.) 7.5 parts by weight,
15 parts by weight of the distyryl compound (25) was placed in a ball mill pot together with 100 parts by weight of a solvent in which methyl ethyl ketone and xylene were mixed in the same amount, and the mixture was dispersed for 48 hours to prepare a photosensitive coating liquid. This coating solution was applied onto an aluminum support and dried to form a photosensitive layer having a thickness of about 15 μm, to prepare a single-layer type photosensitive body.

The photoconductor thus prepared was used as a commercially available electrophotographic copying machine (EP-450Z manufactured by Minolta Camera Co., Ltd.).
V ₀ , E _1/2 , and DDR ₁ were measured by the same method as in Example 1 except that the device was installed in the apparatus and charged by a corona discharge of +6 Kv, and the results are shown in Table 3.

Further, regarding the photoconductor of Example 18 and the photoconductors of Example 19 and Comparative Examples 8 to 11 described later, a commercially available electrophotographic copying machine (EP-350 manufactured by Minolta Camera Co., Ltd.) was used.
Z) was repeatedly photographed during positive charging. V ₀ before and after actual copying of 10,000 sheets for each photoconductor,
E _1/2 and residual potential V _R (V) were measured, and the results are shown in Table 4.
In addition, the image characteristics after the actual copying of 10,000 sheets were evaluated. In the photoconductors of Examples 18 and 19, the sensitivity did not change as in the initial stage, and the gradation was excellent in the final image.
A clear image was obtained, and it was confirmed that the photoreceptor of the present invention was stable in repeatability.

Examples 19 to 21 Three kinds were prepared in the same manner as in Example 18 except that the distyryl compounds (27), (31) and (37) were used in place of the distyryl compound (25) used in Example 18. A photoconductor was manufactured.
V ₀ , E _1/2 , D was obtained in the same manner as in Example 1 except that each photoconductor was charged by a corona discharge of +6 Kv.
DR ₁ was measured and the results are shown in Table 3.

Comparative Examples 1 to 4 Instead of the distyryl compound (25) used in Example 18, the distyryl compounds (1-1), (1-2) and (1
Three types of single-layer type photoconductors were produced in the same manner as in Example 18 except that (3) and (1-4) were used. Further, V ₀ , E _1/2 and DDR ₁ were measured in the same manner as in Example 1 except that each photoconductor was charged by +6 Kv corona discharge, and the results are shown in Table 3.

[0087]

[Chemical 25]

Comparative Examples 5-8 Instead of the distyryl compound (25) used in Example 18, the distyryl compounds (1-5), (1-6) and (1
Three types of single-layer type photoconductors were produced in the same manner as in Example 18 except that (7) and (1-8) were used. Further, V ₀ , E _1/2 and DDR ₁ were measured in the same manner as in Example 1 except that each photosensitive member was charged by +6 Kv corona discharge, and the results are shown in Table 3. In Comparative Examples 5 to 8,
The compounds (1-5), (1-6), (1-7) and (1-8) had poor compatibility with the binder resin, and some crystals were precipitated during the coating of the photosensitive layer.

[0089]

[Chemical formula 26]

[0090]

[Table 2]

[0091]

[Table 3]

[0092]

[Table 4]

[0093]

EFFECT OF THE INVENTION The photoreceptor of the present invention has a photosensitive layer containing the above-mentioned distyryl compound, and thus provides a photoreceptor having excellent charge transporting properties, and particularly less fatigue deterioration and increase in residual potential after repeated use. I was able to.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a photoreceptor according to the present invention in which a charge generation layer and a charge transport layer are laminated on a conductive support.

FIG. 2 is a schematic cross-sectional view of a photoconductor according to the present invention in which a charge transport layer and a charge generation layer are laminated on a conductive support.

FIG. 3 is a schematic sectional view of a photosensitive member according to the present invention having a photosensitive layer on a conductive support.

FIG. 4 is a schematic cross-sectional view of a photoreceptor according to the present invention in which a surface protective layer is provided on the surface of a single-layer type photoreceptor.

FIG. 5 is a schematic cross-sectional view of a photoreceptor according to the present invention in which an intermediate layer is provided between a conductive support and a photosensitive layer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive support 2 Charge generating material 3 Charge transporting material 4 Photosensitive layer 5 Charge generating layer 6 Charge transporting layer 7 Surface protective layer 8 Intermediate layer

Claims (1)

1. A photoconductor comprising a conductive support and a photosensitive layer containing a distyryl compound represented by the following general formula (I). [Chemical 1] (In the formula, R ₁ and R ₂ are independently a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom, Ar ₁ , Ar ₂ , Ar ₃ ,
Ar _4's each independently represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group, a heterocyclic group or a condensed polycyclic group. However, the case where at least one of Ar ₁ and Ar ₂ is a hydrogen atom and at least one of Ar ₃ and Ar ₄ is a hydrogen atom is excluded. Z is a benzene ring or a residue which is bonded to a nitrogen atom to form a 5-membered ring or a 6-membered ring and may have a substituent. )