JPH0427957A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the electrophotographic sensitive body good in electrophotographic characteristics by incorporating a specified polyamide resin in an undercoat layer, a fluorenone type bisazo pigment as an electric charge generating material and a polyvinyl butyral resin as the binder resin for a charge generating layer. CONSTITUTION:The electrophotographic sensitive body is obtained by successively laminating on a conductive substrate 1, the undercoat layer 5, the charge generating layer 2, and a charge transfer layer 3, and the alcohol-soluble 6, 66, or 6, 10 nylon is contained in the undercoat layer 5, and the fluorenone type bisazo pigment is contained as the charge generating material, and the polyvinyl butyral resin is contained as the binder of the charge generating layer 2. When a photosensitive layer is formed into a 2-layer structure, the best electrophotographic characteristics are obtained. Thus the obtained electrophotographic sensitive body is high in sensitivity, forms a high-quality image and small in variance in the electrophotographic characteristics even at the time of repeated uses.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor, and more specifically to a functionally separated photoreceptor.

[Prior art]

Polyhinyl Rubazole, Oxadiazole, Phthalo,
Organic photoconductive substances such as anine have the advantage of being non-polluting and highly productive compared to inorganic photoconductive substances such as selenium and cadmium sulfide, but their low sensitivity has limited their practical use. There are several proposals for sensitization methods, among which a functionally separated photoreceptor in which a charge generation layer and a charge transport layer are laminated is effective.

The charge generation layer is made of azo pigments such as Sudan Red and Diamond Green B, Alcohol Yellow Pyrenequinone, and Indanthrene Brilliant Violet R.
Quinone pigments such as RP Nato, quinone anine pigments, perylene pigments, indigo pigments such as indigo and thioindigo, bisbenzimidazole pigments such as India First Orange Toner, phthalocyanine pigments such as copper phthalone anine,
It is formed by decomposing a charge-generating substance such as a quinacridone pigment into a binder resin such as polyester, polystyrene, polyvinyl chloride, polyvinyl acetate, acrylic, polyvinylpyrrolidone, methylcellulose, or hydroxypropylmethylcellulose, and coating the resin on a support.

The charge generation layer is a thin film layer, for example, 1 micron or less, in order to shorten the range of photo carriers generated inside the charge generation layer.
Preferably, it is necessary to form a thin film layer with a thickness of 0.5 microns or less. In other words, most of the incident light is absorbed by the charge generation layer to generate many photocarriers, and it is necessary to inject the generated photocarriers into the charge transport layer to avoid deactivation due to recombination and capture. Because there is.

However, when such a thin charge generating layer is coated directly on the support, very slight defects, dirt, and
Deposits, scratches, etc. tend to cause non-uniform film thickness, repellency, unevenness in the number of protrusions, etc.

Therefore, when forming the charge generation layer on the conductive layer, a resin layer is provided in the middle thereof. This resin layer is generally called an undercoat layer or an intermediate layer. Materials for forming this undercoat layer include polyurethane, polyamide, polyvinyl alcohol, Evoquin, ethylene-acrylic acid copolymer, ethylene-vinyl acetate copolymer, casein, methylcellulose, nitrocellulose, alkyd resin, etc. Are known.

However, when such an undercoat layer is interposed between the charge generation layer and the conductive layer, the thickness of the charge generation layer can be made uniform, but on the other hand, the electrical properties of the undercoat layer and the charge The integrity of the generator layer greatly influences the properties of the photoreceptor.

Here, in order to obtain smoothness on the surface of the conductive support, it is preferable that the undercoat layer be as thick as possible; however, the resistance increases and charges are more likely to be accumulated as the thickness increases. Therefore, in order to make the film thick, a material with sufficiently low resistance must be selected. Furthermore, when applying a photoconductive layer on top of this subbing layer,
It is also necessary to have solvent resistance so that it will not be immersed in the solvent.

Therefore, selection of the resin material for the undercoat layer is an important issue.

In addition, charge transport materials used for charge transport are selected from those that have an excellent ability to transport holes generated by light irradiation to the support side, and conventionally, oxazole, thiadiazole,
Styryl, benzofuran, aminostiben, phenazine and other compounds or derivatives thereof have been used.

Furthermore, the binder for dispersing and holding the charge-generating substance and the charge-transporting substance should not only have good dispersion and retention properties of both substances, but also should not impair the electrophotographic properties of the photoreceptor, and should have good printing durability and abrasion resistance. , physical properties such as moisture resistance, and environmental resistance.

Moreover, these charge generating substances, charge transporting substances, and their binders are required to be in harmony with each other to maintain good electrophotographic properties and physical properties of the photoreceptor without impairing other properties. Although these factors determine the life and death of a photoreceptor, it is extremely difficult to obtain a suitable combination.

[Purpose of the invention]

The purpose of the present invention is to provide electrophotographic properties that provide smoothness and cleanliness to the surface of a conductive support, have low resistance and solvent resistance, and have an undercoat layer that does not impair the sensitivity of the photoreceptor. The purpose of the present invention is to provide an electrophotographic photoreceptor with good quality.

[Structure of the invention]

In accordance with the object of the present invention, alcohol-soluble nylon (
We focused on polyamide resin), but the performance fluctuated greatly depending on the thickness of the undercoat layer, and if it was thick, the sensitivity would decrease,
Residual potential increases due to repeated use, and if it is thin, charging performance may deteriorate and image defects may occur.It is difficult to determine the optimum thickness. Unsatisfactory results such as performance fluctuations cannot be achieved. However, nylon 6.66 and 6
Polyamide resin containing No. 10 as a monomer component showed useful effects in accordance with the object of the present invention.

In addition, by combining the polyamide resin subbing layer with a charge generation layer containing a fluorenone bisazo pigment and a polybutyral resin, high sensitivity and high image quality are achieved, and there is little change in electrophotographic characteristics even after repeated use. We obtained knowledge that can be used to develop photoreceptors.

Based on the above findings, the object of the present invention is to: provide an electrophotographic photoreceptor in which a subbing layer/charge generation layer/charge transport layer is sequentially laminated on a conductive support; and 610 as monomer components, (1) contains a fluorenone-based bisazo pigment as a charge generating substance, and (3) contains polyvinyl butyral resin as a binder of the charge generating layer. Achieved by a photographic photoreceptor.

In addition, as an aspect of the present invention, a charge transport layer (referred to as CTL)
It is preferable that the binder contains bisphenol Z-type recarbonate resin, and further contains a charge transport material (CTM).
It is preferable to use a compound having a σ-phenylstilbene structure and/or a compound having a distyryl structure in combination with the charge generating substance (labeled CGM) and a fluorenone-based bisazo pigment.

Further, the present invention will be explained in detail and specifically.

The copolyamide resin used in the present invention is preferably a linear polyamide, and preferably has low or amorphous properties suitable for solution coating. Such a resin can be obtained by copolymerizing a mixture of two or more types of nylon raw materials.

Examples of raw materials for nylon include caprolactam or 6-aminocaproic acid, which is a raw material for nylon 6, hexamethylene diamine, a raw material for nylon 66 and nylon 610, and dicarboxylic acids such as adipic acid and sebacic acid. his(4-amino-/chlorohequinyl)methane, methquine cleandiamine or its hydride, piperazine, 2,5-dimethylpiperazine,
Diamines such as trimethylhexamethylene diamine may also be mentioned.

In the present invention, especially nylon 6/66/61
0 copolymer.

Also, as a commercially available product, Ultramid (BASF Japan Ltd.) 6/6
6/ 610 copolymerized nylon erhamite (DuPont)
Japan) 6/66/6] 0 copolymer nylon, etc.

As for the properties, it has good adhesion and hole blocking properties, and also suppresses the increase in residual potential.

The polyamide resin is dissolved in alcohol such as methanol, ethanol, butanol, etc., but it is also effective to add aromatic hydrocarbons such as toluene, xylene, etc. to improve solution stability. The thickness of the undercoat layer (marked as UCL) is 0.
．． Approximately 01 to 5 μm is suitable.

In the present invention, if a copolymerized polyamide resin is used for LICL, it has excellent adhesion to the support, increases the durability of the photoreceptor, has an electrical resistance of 1011 to 10" Ωcm, lower than other resins, and has almost no charge accumulation. Also, it has good coating properties and gives a thin and smooth surface.

In the electrophotographic photoreceptor of the present invention, a fluorenone disazo pigment is used as the CGM. In particular, when the following fluorenone disazo pigments are used in the present invention, sensitivity,
It shows significantly improved effects in terms of durability, image quality, etc.

The fluorenone-based disazo pigment used in the present invention is represented by the following symbol [F].

Tsuzuriyo (F) Xl and X each represent a halogen atom.

p and q each represent an integer of 0.1 or 2, and when p and q are 2, Xl and X2 may be the same or different groups, respectively.

A represents a group represented by the following - binding allowance CF-]).

- Tsuzuriyo CF-1) In the formula, Ar represents a fluorinated hydrocarbon group, an aromatic carbocyclic group or an aromatic heterocyclic group having a substituent. 2 represents a group of nonmetallic atoms necessary to form a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle. m
and n each represent Ol or an integer of 2. However, m and n never become 0 at the same time.

Specific examples of the fluorenone disazo pigment used in the present invention are listed below, but the present invention is not limited thereto.

Sample No.

The fluorenone disazo pigment represented by CF) used in the present invention can be easily synthesized by two known methods, for example, by the method described in Japanese Patent Application No. 62-304862.

The polyvinyl butyral resin according to the present invention has the following binding margin [
v].

- Tsuzuri (V) In the formula, R represents a hydrogen atom, a methyl group, or an ethyl group. or,
a, b, s and h represent the degree of polymerization.

Generally, the physical and chemical properties of polyvinyl butyral resin vary depending on its composition, and its mechanical properties and solution viscosity vary depending on its degree of polymerization.

The polyvinyl butyral used as the binder of the charge generation layer (denoted as CGL) according to the present invention is obtained by saponifying polyvinyl acetate resin and converting the vinyl acetate portion (a structural unit with a degree of polymerization index S in the binding margin (V)) into the polyvinyl butyral. Produce a polyhinyl alcohol resin to remain, select conditions to leave a vinyl alcohol structural unit with a degree of polymerization index, and create an acetalized structural unit with a degree of polymerization index a of at least one of formaldehyde, acetaldehyde, and propylaldehyde. and butyraldehyde to form a butyralized structural unit with a polymerization degree index, the degree of butyralization is preferably 50 mol% or more, and (a + b) is 5
It is preferably 0 mol% or more.

In addition, a degree of polymerization of 1000 or more is required. The upper limit is 10,000 or less, preferably 5,000 or less.

The binder: bisphenol Z-type recarbonate resin used in the CTL according to the present invention is a polymer containing a repeating unit represented by the following binding margin [z] as a main structural composition.

General formula [z] In the formula, R1 and R2 each represent a halogen atom, a hydrogen atom, a methyl group, an ethyl group or a propyl group.

These polycarbonate resins have improved the drawbacks of conventionally used bisphenol A type carbonates, and since a cyclohexyl ring is formed at the central carbon atom of these polycarbonates, the molecular chain of the polycarbonate is unique. directional alignment is effectively prevented.

This prevents the polycarbonate from crystallizing, causing the solution to gel, or precipitating on the film surface during the formation of the photosensitive layer, thereby preventing property deterioration such as a decrease in yield due to abnormal convexities and image defects due to poor cleaning. be able to. The cyclohexyl ring of the above-mentioned binding margin (Z) directly contributes to these remarkable effects.

Furthermore, in the present invention, by using the polycarbonate shown by the binding margin (Z) as the binder resin, the film has excellent physical properties, excellent electrophotographic properties such as charge retention and sensitivity residual potential, and can be used repeatedly. It is possible to create an electrophotographic photoreceptor that exhibits stable characteristics with little fatigue deterioration even when subjected to.

In addition, when used as a photoreceptor, the surface of the photosensitive layer is less likely to be scratched even when rubbed by a magnetic bra or cleaning blade, and the photosensitive layer has less abrasion, and it has a high printing durability without defective properties such as poor cleaning. Photographic photoreceptors can be created.

The polycarbonate resin of the present invention can be easily synthesized according to a conventional method using, for example, the phenolic compounds shown in the section below.

In the formula, R, and R2 represent a hydrogen atom, a chlorine atom, or a methyl group. However, not all of them are hydrogen atoms.

To illustrate the method for producing the polycarbonate resin of the present invention, specifically, in the presence of an inert solvent such as methylene chloride or 1,2-dichloroethane, the phenolic compound is added to the phenolic compound,
Add an alkaline aqueous solution or pyridine as an acid acceptor,
An example is a method of reacting while introducing phosgene.

When using an alkaline aqueous solution as an acid acceptor, the reaction rate can be increased by using a tertiary amine such as trimethylamine or triethylamine, or a quaternary ammonium compound such as tetrabutylammonium chloride or benzyltributylammonium bromide as a catalyst. do.

Also, if necessary, phenol, p-t
- Monohydric phenol such as butylphenol may be present. The catalyst may be added from the beginning, or any method may be used, such as adding it after the oligomer is produced to increase the molecular weight.

In addition, the type 2 polycarbonate resin according to the present invention may optionally contain a co-condensation type polycarbonate containing other repeating units in addition to the repeating unit of binding margin [Z], such as 4
．． 4'-dihydroxy-3-methylphenyl-1,l-
The physical, chemical, or electrical properties may be adjusted using a polycarbonate prepared by cocondensing a mixture of cyclohexane with a small amount of bisphenol A. Furthermore, if necessary, other polymers may be mixed and used within a range that does not interfere with the intended effect. The mixing ratio in this case is 50wt
% or less is preferable.

Since the binder used in the present invention is polycarbonate-based, it can provide the photoreceptor with the excellent charging performance, repeatability, printing durability, etc. that polycarbonate inherently exhibits.

Specific examples of the repeating unit of type 2 polycarbonate used in the present invention include the following.

In addition to the above-mentioned effects, by further incorporating the exemplary B repeating unit into the layer structure of the present invention, there is a remarkable effect of improving the drawbacks of environmental resistance when polyvinyl butyral is used in CGL.

That is, the photoreceptor obtained with the structure of the present photoreceptor showed a remarkable effect on the increase in residual potential when a large number of sheets were printed under normal temperature and normal humidity conditions or under low temperature and low humidity conditions.

Examples of binders that may be used in combination with the Type 2 polycarbonate used as the binder described above include the following.

(1) Polyester (2) Methacrylic resin (3) Acrylic resin (4) Polyvinyl chloride (5) Polyvinylidene chloride (6) Polystyrene (7) Polyvinyl acetate (8) Styrene copolymer resin (e.g. styrene-butadiene copolymer) polymer, styrene-methyl methacrylate copolymer, etc.) (9) Acrylonitrile copolymer resin (e.g., vinylidene chloride-acrytronitrile copolymer, etc.) (10) Vinyl chloride-vinyl acetate copolymer ( 11)
Vinyl chloride-vinyl acetate-maleic anhydride copolymer (12) Silicone resin (13) Silicone-alkyd resin (14)
Phenolic resin (e.g., phenol-formaldehyde resin, cresol formaldehyde resin, etc.) (15) Styrene-alkyd resin (16) Poly-
N-vinylcarbazole (17) Polyvinyl butyral (18) Polyvinyl formal (+9) Polyhydroxystyrene These binders can be used alone or in combination in the carbonate of the present invention as a mixture of two or more.

Next, the compound having a σ-phenylstilbene structure used in the present invention is represented by the following symbol [T1].

General formula (Tl) In the formula, Ar is an aliphatic group or an aromatic group, Ar
.

represents a phenylene group, and Ar, Ar2 may form a ring. R++ and R+□ represent a hydrogen atom, an aliphatic group, or an aromatic group, and R13 represents an aliphatic group or an aromatic group.

The aromatic group represents a phenyl group, a naphthyl group, or a condensed polycyclic ring, and includes Ar, Arz, Ars+ R++, R+z
, the aliphatic group and aromatic group mentioned in R include an alkyl group,
It may contain substituents such as an alkoxy group, a halogen atom, and an amine group.

Ar, Ar2 may form a ring such as a carbazole ring or an indoline ring, and the ring formed by RIz, R□ is 5 to
It is a 7-membered carbocyclic or heterocyclic ring.

The above compound has a high carrier transport ability and contributes to high sensitivity.

Below, examples of compounds represented by Tsuzuriyo [T1] will be described, It is not limited to this.

Specific example of polymerization of knee binding margin [T1]: Technique 1 I8 +13 'r, -IQ Has a distyryl structure used in the invention rib i -4-Zi
(For R6 items, use the binding margin % formula below.) General formula [1”2] Ar.

ring group, Represents a fused polycyclic heterocyclic group.

Synopsis 3:) Group: fused polycyclic hydrocarbon group, heterocyclic group, fused polycyclic heterocyclic group.

Synopsis of substitution 3 groups: fused polycyclic hydrocarbon group, heterocyclic group, fused polycyclic carbon group 1, Synthesis of substitution 3 groups: fused polycyclic hydrocarbon group, heterocycle basis,
1, R3 represents a fused polycyclic heterocyclic group, and may form a ring together with Ar and 80;
alkoxy 7 groups, fujnoquine groups and 777 groups, halogen radicals L1 carboxyl groups, aryl groups, bitroxyl groups, nitro groups, amino groups, and further substituted or unsubstituted 6 groups; algylamino groups; Represents an arylamino group, an aralkylaquinone, an m-shaped hydrocarbon group, a condensed polycyclic hydrocarbon group, and a heterocyclic group.

R4, Rs and R8 are also substituted with 1. < is unsubstituted syntax 4
,) group, argyl group, 7-cnyl group,! Lukoki Uki, 7
, y-/k) group, and ano group, halogen atom, carpokyl group, acyl group, hydroquinol group, di-1-o group, amino group, further substituted group, < is an unsubstituted continuation six groups ; Represents an arylamino group, an arylamino group, an acylgylamino group, a cyclic hydrocarbon group, a synthetic polycyclic hydrogen group, and a heterocyclic group.

i, l represents an integer from θ to 5, and 1 represents an integer from 0 to 4.

The above-mentioned compound has high performance as a CTM and greatly contributes to high sensitivity.

A specific example of CTM represented by the following C7 general formula [T2] will be given below.

T, -9 T. CR+ T2-II T.

There are no particular restrictions on the 0-ton M that can be used in combination in the present invention, but examples include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidacilone derivatives, imidazolidine derivatives, bis imidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, amine derivatives, oxacylone derivatives,
benzothiazole derivatives, benzimidazole derivatives,
Quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, poly-N-vinylcarbazole, poly-l vinylpyrene,
Poly-9-vinylanthracene and the like.

The CTM used in the present invention is preferably one that not only has an excellent ability to transport holes generated during light irradiation to the support side, but also is suitable for combination with the organic pigment used in the present invention.

Examples of the dispersion medium for the organic pigment used in the present invention include hydrocarbons such as hexane, benzene, toluene, and xylene, methylene chloride, methylene chloride, and methylene chloride.
1,2-dichloroethane, 5yn-tetrachloroethane, cis-1+ 2-dichloroethylene, l.

Halogenated hydrocarbons such as 1.2-trichloroethane, 1,1.1-trichloroethane, 1.2-dichloropropane, chloroform, bromoform, chlorobenzene,
Ketones such as acetone, methyl ethyl ketone, cyclohexanone, esters such as ethyl acetate, butyl acetate, alcohols such as methanol, ethanol, propatool, butanol, cyclohexanol, heptatool, ethylene glycol, methyl cellosolve, ethyl cellosolve, acetic cellosolve, etc. These derivatives, ethers such as tetrahydrofuran, l,4-dioxane, furan, and furfural, acetals, amines such as pyridine, butylamine, diethylamine, ethylenediamine, and isopropanolamine, and amides such as N,N-dimethylformamide, etc. In addition to nitrogen compounds, examples include fatty acids, phenols, sulfur and phosphorus compounds such as carbon disulfide and triethyl phosphate.

The polyvinyl butyral and Z-type polycarbonate according to the present invention are CTL of a functionally separated photoreceptor.

Alternatively, they may be mixed with each other as long as the functions of each CGL layer are not impaired.

The photosensitive layer structure of the photoreceptor of the present invention adopts a laminated structure, but if necessary, a protective layer (0CL) provided as a surface layer and a CT
At least one electron-accepting substance may be contained in any one of L, CGL, or UCL, or a plurality of layers thereof, for the purpose of improving sensitivity, reducing residual potential, or reducing fatigue during repeated use.

Additionally, silicone oil may be present as a surface modifier. Further, an ammonium compound may be contained as a durability improver.

Furthermore, ultraviolet absorbers, antioxidants, etc. may be used.

Preferred ultraviolet absorbers include nitrogen-containing compounds such as benzoic acid, stilbene compounds and derivatives thereof, triazole compounds, imidazole compounds, triazine compounds, coumarin compounds, oxadiazole compounds, thiazole compounds and derivatives thereof.

Examples of the antioxidant include hindered phenol, hindered amine, paraphenylene diamine, aryl alkane, hydroquinone, spirochroman, spiroindanone and derivatives thereof, organic sulfur compounds, organic phosphorus compounds, and the like.

If necessary, the CGL according to the present invention may contain less than 5 Qwt% of a thermoplastic resin for the purpose of improving processability and physical properties (preventing cracks, imparting flexibility, etc.).

As the conductive support used in the construction of the electrophotographic photoreceptor of the present invention, the following are mainly used, but the support is not limited thereto.

l) Metal plates such as aluminum plates and stainless steel plates.

2) A thin layer of metal such as aluminum, palladium, or gold is provided on a support such as paper or plastic film by lamination or vapor deposition.

3) A layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is provided on a support such as paper or a plastic film by coating or vapor deposition.

The photoreceptor of the present invention has a conductive support 1 as shown in FIG.
A photosensitive layer 4 made of a laminate of CGL 2 containing CGM as a main component and CTL 3 containing CTM as a main component on top.
will be established. Further, a UCL 5 is provided on the conductive support 1. When the photosensitive layer 4 has a two-layer structure in this manner, an electrophotographic photoreceptor having the best electrophotographic properties can be obtained.

Furthermore, a protective layer 6 may be provided on the photosensitive layer 4, as shown in FIG. 2, if necessary.

Further, the CGL 2 constituting the photosensitive layer 4 having a two-layer structure is UC
It can be formed by the following method directly on the conductive support 1 having L 5 or after providing an intermediate layer such as an adhesive layer or a blocking layer as necessary.

(1) A method of applying a solution in which CGM is dissolved in a suitable solvent. (2) A dispersion liquid obtained by forming CGM into fine particles in a dispersion medium using a ball mill, sand grinder, etc. and mixing and dispersing the CGM with a binder as necessary. How to apply.

Specifically, dipping, spraying, blading,
Application methods such as roll methods are optionally used.

The thickness of CGL2 formed in this way is 0.01
~5μm is preferred, more preferably 0.05μm.
~3 μm.

Further, the thickness of the CTL 3 can be changed as necessary, but it is usually preferably 5 to 30 μm. The composition ratio in CTL3 is preferably 0.1 to 5 vt of the binder to parts by weight (denoted as wt) of the CTM of the present invention. It is also possible to disperse particulate CGM in CTL 3.

Further, when the CGL is configured as a dispersed type in a binder, it is preferable to use the binder in a range of 5 wt or less relative to the CGM l vt.

The photoreceptor of the present invention has the above-mentioned structure, and is excellent in charge-charging characteristics, sensitivity characteristics, and image forming characteristics, as is clear from the examples described below.

In particular, even when subjected to a reversal development system, fatigue deterioration is small, image quality is good, and durability is excellent.

〔Example〕

Examples of the present invention will be specifically described below, but the embodiments of the present invention are not limited thereby.
Elbamide 8061 (manufactured by DuPont) 5g 50°
A tlcL coating solution was prepared by dissolving 800ml of warmed methanol (+) and adding 200ml of nibtanol + nQ.AQn ring was immersed in the LICL coating solution to a thickness of 0.
Form a 1 μm uCL.

Next, as a binder for CGL, 8 g of polyvinyl) (tyral resin: Elex BX-) (manufactured by Kasumi Kagaku Co., Ltd.) was added to 1010 g.
After dissolving in 0O methyl ethyl ketone, 20 g of CGM exemplified compound F-23 was added and dispersed for 30 hours using a sand grinder to prepare a CGL coating solution, which was dip coated onto the UCL to a thickness of 0.4 μm. CGL was formed.

Furthermore, type 2 polycarbonate resin as a binder for CTL; 200 g of Kneepilon Z-200 (manufactured by Mitsubishi Gas Chemical)
was dissolved in 1,2-dichloroethane 10100O+, and C
A CTL coating solution was prepared by adding 150 g of TM exemplified compound T+-2 (α-phenylstilbene type), and the solution was dip-coated onto the CGL to form a CTL with a dry thickness of 17 μm.

After that, dry for 100"0160 minutes and LICL/
A photoreceptor of the present invention was prepared and assembled in the order of CGL/C.

Furthermore, following the same preparation and creation conditions as in Example 1, CG
Example 2~ by changing the combination of M, CTM and binder
Sample photoreceptors of Comparative Example 7 and Comparative Examples 1 and 2 were prepared.

Example 2 An example of CTM of Example 1 T! Changed to -10.

Example 3 5i! The CGM of Example 1 was changed to Example F-15.

Example 4 The CGM of Example 1 is designated as example F-15, and the CTM is designated as example T.

Changed to -10.

Example 5 The binder of CTL in Example 1 was changed to polyvinyl butyral resin Esle Tsuku BM-5 (manufactured by Fukusuihi Gakusha).

Example 6 IJcL resin of Example 1 was mixed with nylon 6/nylon 66/
Changed to nylon 610 copolymer (L) (Mite 8062, manufactured by DuPont).

Example 7 The IJcL resin of Example 1 was mixed with nylon 6/nylon 66/
Changed to nylon 610 copolymer (ELL (Might 8063, manufactured by DuPont) and CGM to Example F-4.

Comparative Example 1 The IJCL resin of Example 1 was used as CM-8000 (manufactured by Toshisha Co., Ltd.)
Changed to.

Comparative Example 2 The CGL/(inder) of Example 1 was changed to polycarbonate resin Kneepilon Z-200 (manufactured by Mitsubishi Gas Ihigakusha).

Comparative Example 3 A sample was prepared in the same manner as in Example 1 except that UCL was not coated.

The obtained photoreceptor was transferred to an electrophotographic copying machine U-Bix2025.
(Manufactured by Konica) We installed it on a modified machine and conducted a 10,000-copy live-action test. Around 100,000 copies, the charging potential Va (V) at the development position and the surface potential were changed from 600V to 100V.
Expressed as the exposure amount required to attenuate to V; Sensitivity E'
, ::(lx-sec) Measure the residual potential Vr (V) t
:. The results are shown in Tables 1 and 2.

The photoreceptors of Examples 1 to 7 provided good image quality with high density, no fogging, and no unevenness over 100,000 copies. Also, there is little change in electrophotographic properties.

On the other hand, in the photosensitive pairs of Comparative Examples 1 to 3, fogging occurred in the images after 100,000 copies. Furthermore, in Comparative Example 2, unevenness was observed in the image from the beginning, and it was found that this was due to unevenness in the CGL of the photoreceptor. In Comparative Example 3, many fine dot-like white defects were observed in the image from the beginning.

As described above, the photoreceptor of the present invention has high sensitivity and long-term use.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views showing examples of the mechanical structure of the photoreceptor of the present invention, respectively. 1... Conductive support 2... Carrier generation layer 3... Carrier transport layer 4... Photosensitive layer 5... Subbing layer 6... Protective layer

Claims (3)

[Claims] (1) In an electrophotographic photoreceptor in which a subbing layer/charge generation layer/charge transport layer are sequentially laminated on a conductive support, (a) the subbing layer is made of an alcohol-soluble polyamide containing nylon 6, 66, and 610 as monomer components; A hand electrophotographic photoreceptor comprising: (b) a fluorenone-based bisazo pigment as a charge generating substance; and (c) a polyvinyl butyral resin as a binder of the charge generating layer. (2) The electrophotographic photoreceptor according to claim 1, wherein the binder of the charge transport layer contains bisphenol Z-type polycarbonate resin. (3) The electrophotographic photoreceptor according to claim 1 or 2, which contains a compound having an α-phenylstilbene structure and/or a compound having a distyryl structure as a charge transport substance.