JPS63271462A - Organic photosensitive body - Google Patents

Abstract

PURPOSE:To increase the sensitivity and surface potential of a photosensitive body and to reduce the residual potential by using different specified compds. as an electric charge generating material, an electric charge transferring material and a binding resin. CONSTITUTION:In the single layer type photosensitive layer of a photosensitive body, a perylene compd. (A) represented by formula I is used as an electric charge generating material, a hydrazone compd. (B) represented by formula II as an electric charge transferring material and poly(4,4'-cyclohexylidene diphenyl) carbonate as a binding resin. In the formulae, each of R<1>-R<4> is lower alkyl or lower alkoxy and R<5> is H or lower alkyl. N,N'-di(3,5-dimethylphenyl) perylene-3,4,9,10-tetracarboxydi-imide is preferably used as the compd. A and N-methyl-3-carbazolylaldehyde N,N-diphenylhydrazone as the compd. B.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an organic photoreceptor, and more particularly to an organic photoreceptor suitable as an electrophotographic photoreceptor.

<Problems to be solved by conventional technology and inventions> In recent years,
As a photoreceptor for electrophotography, an organic photoreceptor is used because it has good processability and is advantageous in terms of manufacturing cost, and also has a large degree of freedom in functional design. In particular, functionally separated organic photoreceptors are becoming more and more popular because they can achieve higher sensitivity by separating each function using a charge-generating material that generates a charge when irradiated with light and a charge-transporting material that transports the generated charge. It is being For example, a single-layer type photoreceptor in which a polycyclic aromatic hydrocarbon is contained in a polyvinylcarbazole-based photoconductor as a charge transport material (Japanese Patent Application Laid-Open No. 143438), a bisazo-based photoconductor as a charge-generating material, etc. a charge generation layer containing a pigment;
Certain hydrazone compounds and poly(
4,4'-cyclohexylidene diphenyl) carbonate and a charge transport layer (see JP-A No. 81-2707H);
A multi-layer photoreceptor (special photoreceptor) in which a charge generation layer containing a perylene pigment as a charge generation material and a charge transport layer containing a specific hydrazone compound as a charge transport material are laminated on a conductive substrate. (Refer to Publication No. 55-15H54)
It has been known.

The single-layer photoconductor described above can be produced simply by dispersing polycyclic aromatic hydrocarbon in a polyvinylcarbazole photoconductor, coating it on a conductive substrate, and drying it. Good sex. In addition, in the case of the above-mentioned single-layer photoconductor, not only can it be positively charged, but also a toner that can be negatively charged is generally easily obtained as a toner for developing the electrostatic latent image on the photoconductor, so the selection of toner materials is advantageous. It has the advantage of being wide and allowing the use of various toner materials.

However, the above-mentioned single-layer photoreceptor in which a polycyclic aromatic hydrocarbon is dispersed in a polyvinylcarbazole-based photoconductor does not have sufficient sensitivity, and the material constituting the photosensitive layer must be carefully selected. The choice of material for the photosensitive layer is narrow. In addition, the above-mentioned single-layer photoreceptor has a low surface potential during corona charging and a large residual potential, and the surface potential decreases with repeated use, so it does not have sufficient repeatability and is not sufficient as an organic photoreceptor. The problem is that it does not exhibit certain characteristics.

On the other hand, the above-mentioned multi-layer type photoreceptor has a charge generation layer and a charge transport layer that separate each function, so unlike the above-mentioned single-layer type photoreceptor, it has high sensitivity and a wide selection of photosensitive materials. It has the advantage of being spacious. However, since the charge transport material is generally a hole transport substance, it is possible to negatively charge the photoreceptor, but it is difficult to charge it positively.
Contrary to the single-layer type photoreceptor described above, the selection range of toner materials is narrower. Furthermore, since the charge generation layer has a thin layer thickness of 1 to 2 μm, it is not only necessary to form the charge generation layer with high precision, but also to form a charge transport layer on the charge generation layer. This increases the number of manufacturing steps for the body, resulting in poor workability, low yield, and high costs. Furthermore, since ozone is generated when negatively charged by corona discharge, it is necessary to provide an exhaust passage for exhausting ozone in a copying machine or the like, resulting in the problem of an increase in the size of the apparatus. Also,
In order to solve the above-mentioned problems, if a single-layer type photoreceptor is constructed from the charge-generating material and the charge-transporting material, only a photoreceptor with low sensitivity and high residual potential will be obtained, which is suitable for use in electrophotography, etc. The characteristics as a photoreceptor are not sufficient.

<Object of the Invention> The present invention has been made in view of the above problems, and provides an inexpensive single-layer organic photoreceptor that has excellent positive chargeability, high sensitivity and surface potential, and low residual potential. The purpose is to

Means and Effects for Solving the Problems In order to achieve the above objects, the organic photoreceptor of the present invention is a photoreceptor having a single-layer type photoreceptor layer consisting of a charge generating material, a charge transporting material, and a binder resin. In the body, the charge generating material has the following general formula (
It is a perylene compound represented by 1), the charge transport material is a hydrazone compound represented by the following general formula, and the binder resin is poly(4,4''-cyclohexylidene diphenyl) carbonate. It is characterized by:

(In the formula, R', R2, R3 and R4 are the same or different and each represents a lower alkyl group or a lower alkoxy group.) (In the formula, R5° represents a hydrogen atom or a lower alkyl group.) Detailed description of the invention.

The photosensitive layer of the organic photoreceptor of the present invention is a single layer type, and includes a perylene compound represented by the above general formula (1) as the charge generating material and the above general formula (2) as the charge transporting material.
It contains a hydrazone compound represented by and poly(4,4''-cyclohexylidene diphenyl) carbonate as a binder resin.

The lower alkyl group in the above general formula (1) and general formula (2) includes an alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tOrt-butyl, pentyl, and hexyl group. Illustrated.

Examples of the lower alkoxy group in the above general formula (1) include alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, tert-butoxy, pentyloxy, and hexyloxy groups. be done.

The perylene compounds represented by the above general formula (1) include N,N''-di(3,5-dimethylphenyl)perylene-3,4,9,10-tetracarboxydiimide, N,
N”-di(3,5-diethylphenyl)perylene-3,
4,9,10-tetracarboxydiimide, N, N--
di(3-methyl-5-ethylphenyl)perylene-3,
4,9,10-tetracarboxydiimide, N, N--
Di(3,5-dipropylphenyl)perylene-3,4,
9,10-tetracarboxydiimide, N,N--di(
3゜5-diisopropylphenyl)perylene-3,4゜9,lO-tetracarboxydiimide, N,N--di(
3,5-dibutylphenyl)perylene-3゜4, 9.
10-tetracarboxydiimide, NIN'-di(3,
5-di-tert-butylphenyl)perylene-3,4
,9,10-tetracarboxydiimide, N,N--di(3,5-diethylphenyl)perylene-3,4,9,
10-tetracarboxydiimide, N,N-di(3,
5-jexyphenyl)perylene-3,4,9,10-
Tetracarboxydiimide, N,N--di(3-methyl-5-methoxyphenyl)perylene-3,4,9゜10
-tetracarboxydiimide, N,N--di(3-methyl-5-ethoxyphenyl)perylene-3,4,9,t
o-tetracarboxydiimide, N,N''-di(3-ethyl-5-methoxyphenyl)perylene-3,4,9,
10-tetracarboxydiimide, N,N”-di(3-
Propyl-5-methoxyphenyl)perylene-3,4,
9,10-tetracarboxydiimide, N,N--di(
3゜5-dimethoxyphenyl)perylene-3,4,9゜10-tetracarboxydiimide, N,N--di(3,
5-jethoxyphenyl)perylene-3゜4, 9.1
0-tetracarboxydiimide, NIN゛-di(3,5
-dipropoxyphenyl)perylene-3,4,9,10
-tetracarboxydiimide, N, N=-di(3,5-
diisopropoxyphenyl)perylene-3,4,9,1
0-tetracarboxydiimide, N,N″-di(3,5
-dibutoxyphenyl)perylene-3,4,9,10-
Tetracarboxydiimide, N,N--di(3,5-dipentyloxyphenyl)perylene-3,4°9.10
-tetracarboxydiimide, N,N--di(3,5-
dihexyloxyphenyl)perylene-3,4,9,1
Examples include 0-tetracarboxydiimide. Among the above perylene compounds, those having an alkyl group or alkoxy group having 1 to 3 carbon atoms, especially N,N''-di(
3,5-dimethylphenyl)perylene-3,4,9,t
o-Tetracarboxydiimide is preferred. The above perylene compounds may be used alone or in combination of two or more.

Further, as the hydrazone compound represented by the above general formula (2), 3-carbazolyl aldehyde N is used.

N-diphenylhydrazone, N-methyl-3-carbazolyl aldehyde N, N-diphenylhydrazone, N-
Ethyl-3-carbazolylaldehyde N,N-diphenylhydrazone, N-propyl-3-carbazolyl, aldehyde N,N-diphenylhydrazone, N-isopropyl-3-carbazolylaldehyde N,N-diphenylhydrazone, N- Butyl-3-carbazolylaldehyde N, N-diphenylhydrazone, N-inbutyl-
3-Carbazolylaldehyde N,N-diphenylhydrazone, N-1ert-butyl-3-carbazolylaldehyde N,N-diphenylhydrazone, N-pentyl-3-carbazolylaldehyde N,N-diphenylhydrazone, N -Hexyl-3-carbazolyl aldehyde N,N-diphenylhydrazone is exemplified. Among the above hydrazone compounds, those having an alkyl group having 1 to 3 carbon atoms, particularly N-methyl-3-carbazolyl aldehyde N,N-diphenylhydrazone, are preferred. The above hydrazone compounds may be used alone or in combination of two or more.

Further, poly(4,4'-cyclohexylidene diphenyl) carbonate is used as a binder resin for the perylene compound and hydrazone compound. This poly(4,4
As the '-cyclohexylidene diphenyl) carbonate, various kinds can be used, for example, those having a degree of polymerization of about 50 to 5,000.

The above poly(4,4″-cyclohexylidene diphenyl)
By dispersing the perylene compound or the like in carbonate, the sensitivity of the single-layer organic photoreceptor is increased, unlike a single-layer organic photoreceptor using bisphenol A polycarbonate, polyester, or the like. Further, by using the above-mentioned binder resin, not only is the compatibility with the above-mentioned hydrazone compound etc. excellent, but also the abrasion resistance of the photoreceptor and the repeatability of the photoreceptor are excellent. That is, since the perylene compound, the hydrazone compound, and the binder resin are combined, an organic photoreceptor having excellent photosensitive properties, electrical properties, and mechanical properties can be obtained. Also, poly(
When 4,4=-cyclohexylidene diphenyl) carbonate is used, the range of solvents used when preparing the perylene-based compound and hydrazone-based compound dispersion is widened, so the above-mentioned dispersion can be easily prepared. Moreover, the coating properties on conductive substrates are also improved.

More specifically, when the above-mentioned bisphenol A type polycarbonate or polyester is used, the dispersibility of the above-mentioned perylene-based compounds and hydrazone-based compounds is not sufficient, so not only the sensitivity of the photoreceptor is low, but also the durability of the photoreceptor is decreased. Poor abrasion resistance and insufficient repeatability. In particular, the above polyester does not have sufficient abrasion resistance. Additionally, when using the above-mentioned poly(4゜4''-cyclohexylidene diphenyl) carbonate, unlike bisphenol A polycarbonate, for which conventionally only chlorinated solvents such as dichloromethane and monochlorobenzene could be used due to solution stability etc. , tetrahydrofuran, methyl ethyl ketone, and other ketone-based solvents can also be used, which is preferable in terms of safety and hygiene and easy to handle.

The proportions of the perylene compound, hydrazone compound, and binder resin can be appropriately selected depending on the desired characteristics of the organic photoreceptor. 2 to 20 parts by weight of compound, preferably 5 to 10 parts by weight, 40 to 11 parts by weight of hydrazone compound
0 parts by weight, preferably 60 to 90 parts by weight are used.

If the amount of perylene compound and hydrazone compound used is less than the above-mentioned amount, the sensitivity of the photoreceptor will not be sufficient, and the residual potential will increase. Further, if the amount exceeds the above range, the abrasion resistance of the photoreceptor will not be sufficient.

Note that normally, if a large amount of the above perylene compound is used, the positive chargeability will not be sufficient, and if a small amount is used, the sensitivity etc. will decrease. and a binder resin, this organic photoreceptor has high sensitivity and surface potential even with a small amount of perylene compound, and has excellent positive chargeability with small residual potential, abrasion resistance, and repeatability. can be obtained.

Further, the above-mentioned perylene compounds may have spectral sensitivity on the short wavelength side. Therefore, in applications requiring color reproducibility in the blue region, it is preferable to use various spectral sensitizers, and it is particularly preferable to use phthalocyanine compounds.

Various types of phthalocyanine compounds can be used, but metal-free phthalocyanine is preferred.

The metal-free phthalocyanine may have an appropriate particle size, but preferably has an average particle size of 0.1 μm or less. The average particle size of metal-free phthalocyanine is 0.1
If it exceeds μm, the sensitivity of the photoreceptor decreases. The above average particle diameter was determined by a light scattering method (device name: dynamic light scattering photometer).

Further, metal-free phthalocyanine can be used in an appropriate amount, but 0.000 parts by weight per 100 parts by weight of the above-mentioned binder resin.
It is preferable to add 2 to 1 part by weight. If the amount added is less than 0.2 parts by weight, the blue reproducibility will not be sufficient, and if it exceeds 1 part by weight, the metal-free phthalocyanine will have spectral sensitivity in the red region, resulting in insufficient red reproducibility.

In addition, among the above metal-free phthalocyanines, β-type metal-free phthalocyanine, especially the average particle size of 0.005
~0.05μI is preferred. When the average particle size of the β-type metal-free phthalocyanine is less than 0.005 μm, the dispersibility is insufficient, and when it exceeds 0.05771, the sensitivity of the photoreceptor decreases.

Furthermore, in order to enhance the stability of the photoreceptor containing the metal-free phthalocyanine, it is preferable to use a phthalocyanine pigment such as aluminum phthalocyanine or titanyl phthalocyanine, especially copper phthalocyanine, together with the metal-free phthalocyanine. Further, copper phthalocyanine can be used in an appropriate amount, but 1 to 10% by weight, particularly 3 to 10% by weight, based on the metal-free phthalocyanine.
Preferably, 10% by weight is used. If the amount of copper phthalocyanine is less than 1% by weight, it is not sufficient to stabilize the metal-free phthalocyanine, and if it exceeds 10% by weight, the surface potential will decrease. Note that as the amount of copper phthalocyanine increases, the stabilizing effect of metal-free phthalocyanine increases, and the residual potential of the photoreceptor also decreases.

Further, it is even more preferable to use the copper phthalocyanine in combination with the β-type metal-free phthalocyanine, and in this case, the average particle size of the copper phthalocyanine is 0.0.
It is preferable to use 0.01% or less. In particular, in order to obtain a stable organic photoreceptor with a small residual potential by reducing the amount of copper phthalocyanine, it is preferable to co-precipitate the copper phthalocyanine with metal-free phthalocyanine. The coprecipitation described above can be carried out by a conventional method, for example, by dropping a sulfuric acid solution of steel phthalocyanine and metal-free phthalocyanine into water or the like during the production of copper phthalocyanine. The phthalocyanine obtained by the above-mentioned coprecipitation not only becomes fine particles of copper phthalocyanine, but also almost eliminates deterioration of electrical properties due to the thermal history of the photoreceptor, and also provides a photoreceptor with low residual potential and excellent color reproducibility. It will be done. In addition, in the phthalocyanine produced by the above coprecipitation method, in order to improve blue reproducibility with a small amount, the average particle size of the copper phthalocyanine is 0.0.
It is preferable that the particle diameter is 0.01 μm or less.

The photosensitive layer having the above composition may contain other charge-generating materials, charge-transporting materials, etc., as long as they do not impede the photosensitive properties. Examples of the charge generating materials include selenium, selenium-tellurium, amorphous silicon, pyrylium salts, azo pigments, disazo pigments, anthanthrone pigments, phthalocyanine pigments, indigo pigments, triphenylmethane pigments, and slenium pigments. Examples include pigments, toluidine pigments, pyrazoline pigments, other perylene pigments, and quinacridone pigments. In addition, examples of the charge transport material include tetracyanoethylene, 2.4.7-
) Fluorenone compounds such as dinitro-9-fluorenone, nitrated compounds such as 2,4.8-)linitrothioxanthone and dinitroanthracene, succinic anhydride, maleic anhydride, dibromomaleic anhydride, 2,5-di( 4
Oxadiazole compounds such as -dimethylaminophenyl)-1,3,4-oxadiazole, styryl compounds such as 9-(4-diethylaminostyryl)anthracene, carbazole compounds such as polyvinylcarbazole, 1-phenyl- 3-(p-dimethylaminophenyl)
Nitrogen-containing cyclic compounds such as pyrazoline compounds such as pyrazoline, indole compounds, oxazole compounds, inoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, triazole compounds, and fused polycycles Examples include compounds of the above group. Furthermore, conventionally known sensitizers such as terphenyl, halonaphthoquinones, and acenaphthylene may be used.

Further, the above binder resin may be used in combination with other conventionally known binder resins. Examples of the other binder resins include styrene polymers, acrylic polymers, styrene-acrylic copolymers, polyethylene, ethylene-vinyl acetate copolymers, chlorinated polyethylene, polypropylene, and olefin-based ionomers. Polymers, polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, polyesters, alkyd resins, polyamides, polyurethanes, epoxy resins, other polycarbonates, polyarylates, polysulfones, diallyl phthalate resins, silicone resins, ketone resins,
Examples include polyvinyl butyral resin, polyether resin, phenol resin, and photocurable resin such as epoxy acrylate. The above binder resins may be used alone or in combination of two or more.

The photosensitive layer of the organic photoreceptor containing the above-mentioned perylene compound, hydrazone compound, binder resin, etc. may have an appropriate thickness;
It is preferable to have a thickness of μ■, and is formed by preparing a dispersion of the above-mentioned perylene compound, applying it to a conductive substrate, and removing the solvent.

The above-mentioned conductive substrate may be in the form of a sheet or a drum, and it is preferable that the substrate itself is conductive or the surface of the substrate is conductive and has sufficient mechanical strength when used. . Various conductive materials can be used as the conductive substrate, such as aluminum, copper,
tin, platinum, gold, silver, vanadium, molybdenum, chromium,
Examples include simple metals such as cadmium, titanium, nickel, palladium, indium, stainless steel, and brass, plastic materials on which the above metals are vapor-deposited or laminated, and glass coated with aluminum iodide, tin oxide, indium oxide, etc. . Among the above-mentioned conductive substrates, aluminum is preferable, and in particular, aluminum crystal grains are not present on the surface, preventing the occurrence of black spots and pinholes in copied images, etc., and the above-mentioned perylene compounds, hydrazone, etc. In order to improve the contact between the photosensitive layer containing compounds, etc. and the substrate, alumite-treated aluminum,
Among them, the thickness of the alumite treatment layer is 5 to 12 μm,
Alumite-treated aluminum with a surface roughness of 1.5s or less is preferred.

Moreover, various organic solvents can be used when preparing the above-mentioned dispersion liquid. Examples of the solvent include aliphatic hydrocarbons such as n-hexane, octane, and cyclohexane;
Aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as dichloromethane, dichloroethane, carbon tetrachloride, and chlorobenzene; ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and diethylene glycol dimethyl ether; , ketones such as acetone, methyl ethyl ketone, and cyclohexanone, esters such as ethyl acetate and methyl acetate, dimethyl formamide, and dimethyl sulfoxide, which are used either -S or a mixture of two or more thereof. In addition, when preparing the above-mentioned dispersion, a surfactant, a leveling agent, etc. may be used in combination in order to improve dispersibility, coating properties, etc.

Further, the above-mentioned dispersion liquid can be prepared using a conventional method such as a ball mill, a paint shaker, a sand mill, an attritor, an ultrasonic disperser, etc., and the obtained dispersion liquid is applied to the conductive substrate. The organic photoreceptor of the present invention can be obtained by heating and removing the solvent.

The photosensitive layer of the organic photoreceptor of the present invention has a photosensitive layer containing a specific perylene compound, a hydrazone compound, and a specific polycarbonate, and therefore has excellent positive chargeability and a single-layer structure. Although it is a photoreceptor, it has high sensitivity and surface potential, and low residual potential. Further, since it is a single-layer type photoreceptor, an inexpensive organic photoreceptor can be easily manufactured with high yield. Therefore, the organic photoreceptor of the present invention is useful as a photoreceptor used in various applications such as copying machines and laser printers.

<Examples> The present invention will be described in more detail below based on Examples.

Example I N,N--di(3,5-dimethylphenyl)perylene-
8 parts by weight of 3,4,9,10-tetracarboxydiimide, N-methyl-3-carbazolyl aldehyde N,N-
Using 75 parts by weight of diphenylhydrazone, 100 parts by weight of poly(4,4'-cyclohexylidene diphenyl) carbonate (product name: Polycarbonate Z, manufactured by Mitsubishi Gas Chemical Co., Ltd.) and a predetermined amount of tetrahydrofuran, using an ultrasonic disperser. A dispersion was prepared and coated on an alumite-treated aluminum plate to produce an organic photoreceptor having a photosensitive layer with a thickness of about 20 μm.

Example 2 N-methyl-3-carbazolyl aldehyde of Example 1
1. Using N-isopropyl-3-carbazolyl aldehyde N,N-diphenylhydrazone instead of N,N-diphenylhydrazone. An organic photoreceptor was produced in the same manner as in Example 1 above.

Example 3 N, N=-di(3,5-dimethylphenyl) of Example 1
In place of perylene-3,4,9,10-tetracarboxydiimide, N,N--di(3,5-dimethoxyphenyl)perylene-3,4,9°lO-tetracarboxydiimide is used to carry out the above procedure. An organic photoreceptor was produced in the same manner as in Example 1.

Example 4 N,N″-di(3,5-dimethoxyphenyl)perylene-3,4,9,10-tetracarboxydiimide and N-ethyl-3-carbazolyl aldehyde of Example 3
An organic photoreceptor was prepared in the same manner as in Example 1 using N,N-diphenylhydrazone.

Comparative Example 1 Polyester (Toyobo I
Using Vylon RV200 (trade name, manufactured by II Co., Ltd.),
An organic photoreceptor was produced in the same manner as in the above example.

Comparative Example 2 In place of the poly(4,4'-cyclohexylidene diphenyl) carbonate and tetrahydrofuran of Example 1, bisphenol A type polycarbonate (trade name: Panlite L, manufactured by Ontaisha) and dichloromethane were used, and the same as in the above example was used. An organic photoreceptor was produced in the same manner.

Comparative Example 3 N-methyl-3-carbazolyl aldehyde of Example 1
N,N-diethylaminobenzaldehyde N instead of N,N-diphenylhydrazone.

An organic photoreceptor was prepared in the same manner as in Example 1 using N-diphenylhydrazone.

Comparative Example 4 N-methyl-3-carbazolyl aldehyde of Example 1
N,N-diphenylaminobenzaldehyde N instead of N,N-diphenylhydrazone.

An organic photoreceptor was prepared in the same manner as in Example 1 using N-diphenylhydrazone.

Comparative Example 5 In place of the perylene compound and hydrazone compound of Example 1, N,N--dimethylperylene-3,4,9,
to-tetracarboxydiimide and N-ethyl-6
-Medoxy 3-carbazolylaldehyde An a-organic photoreceptor was prepared in the same manner as in Example 1 above using N-methyl-N-phenylhydrazone.

Comparative Example 6 An organic photoreceptor was produced in the same manner as in Example 1 except that the perylene compound of Example 1 was replaced with a bisazo pigment.

In order to investigate the charging characteristics and photosensitivity characteristics of the above-mentioned electrophotographic photoreceptor, an electrostatic copying paper tester (manufactured by Kawaguchi Electric Co., Ltd., 5
The organic photoreceptors of each of the Examples and Comparative Examples were positively charged by performing corona discharge under the conditions of +6.0 KV using a photoreceptor (type P-428).

In addition, the surface potential V s, p, (V) of each photoreceptor was measured, and the surface of the photoreceptor was exposed to light using a tungsten lamp with the illuminance adjusted so that the surface of the photoreceptor was 10 lux. The potential V s,p is 1
/2, and find the half-decreased exposure amount El/2 (μ
J/cj) was calculated. Also, after exposure, 0.15
The surface potential after seconds has passed is the residual potential V r,p.

(v).

In addition, it was also investigated whether the surface potential would decrease after repeated use 1000 times. Note that the surface potential of the photoreceptor hardly decreases due to repeated use of the photoreceptor as ○,
Items that were significantly degraded and were not practical were evaluated as ×.

Furthermore, using a copying machine equipped with the above-mentioned photoreceptors, each photoreceptor was set to +8. It was corona charged under OKV conditions, exposed, and developed with dry toner. In addition, the process of scraping off the residual toner on the photoreceptor with a polyurethane blade in pressure contact with the photoreceptor was repeated 15 times, that is, 15 copies were made, and the degree of wear (μn) on each photoreceptor was examined. , the abrasion resistance was evaluated.

The results of the charging characteristics, photosensitivity characteristics, repeatability characteristics, etc. of each organic photoreceptor obtained in the above Examples and Comparative Examples are shown in the table.

As is clear from the table, all of the organic photoreceptors of the present invention were found to have a small half-life exposure, good sensitivity, and a small residual potential. Further, it was found that all of the examples did not accumulate residual potential even after repeated use, did not have a large residual potential, and were excellent in repeatability and wear resistance. On the other hand, all of the photoreceptors of Comparative Examples had insufficient sensitivity and high residual potential.

In particular, polyester and bisphenol A are used as binder resins.
Comparative Examples 1 and 2 using type polycarbonate both had insufficient abrasion resistance, and Comparative Example 3 had a large decrease in surface potential due to repeated use and did not have sufficient repeatability. Moreover, the surface potential of Comparative Example 5 was low.

<Effects of the Invention> As described above, according to the organic photoreceptor of the present invention, the photosensitive layer contains a specific perylene compound, hydrazone compound, and poly(4,4'-cyclohexylidene diphenyl) carbonate. In addition to having excellent positive chargeability, the photoreceptor has a single-layer structure, has high sensitivity and surface potential, and has a small residual potential. Also,
In addition to being excellent in abrasion resistance and repeatability, since it is a single-layer type photoreceptor, it has the unique effects of being easily manufactured at a high yield and being inexpensive.

Claims (1)

[Scope of Claims] 1. A photoreceptor having a single-layer photosensitive layer comprising a charge-generating material, a charge-transporting material, and a binder resin, wherein the charge-generating material is perylene represented by the following general formula (1). The charge transport material is a hydrazone compound represented by the following general formula (2), and the binder resin is poly(4
, 4'-cyclohexylidene diphenyl) carbonate. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) (In the formula, R^1, R^2, R^3, and R^4 are the same or different and represent a lower alkyl group or a lower alkoxy group.) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(2) (In the formula, R^5 represents a hydrogen atom or a lower alkyl group) 2. Perylene compounds are N,N'-di(3,5-dimethylphenyl) ) The organic photoreceptor according to claim 1, which is perylene-3,4,9,10-tetracarboxydiimide. 3. The organic photoreceptor according to claim 1, wherein the hydrazone compound is N-methyl-3-carbazolylaldehyde N,N-diphenylhydrazone. 4. The photosensitive layer contains 2 to 20 parts by weight of a perylene compound and a hydrazone compound based on 100 parts by weight of the binder resin.
The organic photoreceptor according to claim 1, containing 0 to 110 parts by weight.