JPH0882940A - Production of electrophotographic photoreceptor and its photosensitive layer - Google Patents

Abstract

PURPOSE: To improve the adhesion of a photosensitive layer of an electro- photographic photoreceptor to the substrate and to prevent the peeling of a film at the time of repetitive use by adding a specified additive to the photoreceptor. CONSTITUTION: Silicone oil is added to one of the photosensitive layers of an electrophotographic photoreceptor as a layer brought into contact with the substrate so as to improve the adhesion of the layer to the substrate and to prevent the peeling off of a film at the time of repetitive use. A coating film excellent in adhesion can easily be formed by adding silicone oil to a coating soln. used for forming the layer and coating a substrate with the resultant coating soln.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoconductor for electrophotography which is used when an image is formed by an electrophotographic process such as a copying machine, a printer or a facsimile and a method for producing a photosensitive layer thereof.

[0002]

2. Description of the Related Art Recently, in this type of electrophotographic photoreceptor,
Materials using organic materials, which are advantageous in terms of cost and ease of disposal, have come to be used in many cases. In addition, as a support for these electrophotographic photoconductors, a support in which an intermediate layer containing a resin as a main component is formed on the surface of a metal aluminum drum has been widely used in the past. Those that form an oxide film and do not have an intermediate layer have also been used.

In this case, since the charge generation layer is directly provided on the metal surface having the anodized film, the adhesion of the film becomes weaker than the case where the charge generation layer is provided through the intermediate layer. For this reason, there arises a problem that the film peels off during repeated use.

[0004]

Since the adhesion of the photosensitive layer to the support affects the durability of the drum, various methods have been tried to improve the adhesion. However, if the resin is changed to improve the adhesion,
Due to the characteristics peculiar to the resin, there have been problems such as an increase in dark attenuation rate and defects such as fog appearing in the image. In addition, when an intermediate layer, which has been used conventionally, is formed on the anodized film, and a photosensitive layer is formed thereon, the adhesion is improved, but the residual potential rises significantly and does not affect other characteristics. A method for improving the adhesion has not yet been found.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor having sufficient adhesion to the metal surface of the charge generating layer and having sufficient durability even after repeated use, and It is an object of the present invention to provide a method for manufacturing a photoconductor for electrophotography.

Therefore, in the electrophotographic photoreceptor of the present invention,
Adhesion is improved by including silicone oil in the layer in contact with the support, and a charge generation layer having excellent adhesion can be easily obtained by the manufacturing method in which silicone oil is added to the coating material forming the layer. The layer in contact with the support is the charge generation layer or the charge transfer layer. This is because the order of forming the charge generation layer and the charge transfer layer may be opposite to each other.

The silicone oil used in the present invention may be, for example, SH21PA manufactured by Toray Dow Corning Co., Ltd. or other commercially available ones, but those which are not easily affected by environmental changes are desirable.
The addition amount of silicone oil can be appropriately selected within a range where the effect is recognized, but it is preferably about 50 to 1000 ppm in weight ratio with respect to the elements constituting the film of the layer in contact with the support. If the amount added is too small, the effect of the addition does not appear, while if it is too large, the electrophotographic characteristics of the photosensitive layer are likely to be adversely affected. When silicon oil is added to the charge generation layer or the charge transfer layer, the addition method may be a method of impregnating the charge generation layer or the charge transfer layer after forming it, or a coating used when forming the charge generation layer or the charge transfer layer. Although it is possible to add it to the liquid,
If anything, the latter method of adding to the coating solution is preferable. By forming a layer containing silicon oil by this method, an electrophotographic photoreceptor having sufficient durability and adhesion can be easily obtained without increasing the number of manufacturing steps.

The electrophotographic photosensitive member used in the present invention has a photosensitive layer formed on a conductive support. The photosensitive layer has a charge generating layer and a charge transfer layer, and may be further protected. Some include a plurality of layers in which layers are laminated, ones formed only by a charge generation layer, or one formed by a single layer in which a charge transfer material is mixed in the charge generation layer.

The conductive support used in the present invention has an anodized film on the surface of a support itself having conductivity, for example, a metal such as aluminum, titanium, zinc, copper, chromium, nickel, or an alloy thereof. An oxide film such as is formed.

The charge generation layer is composed of a resin layer in which a charge generation material is dispersed or compatible with a resin, or a mixture of this resin layer and a charge transfer material.

As the charge generating material, known materials such as various phthalocyanine pigments, azo pigments, disazo pigments, indigo pigments and quinacridone pigments are used. Further, these charge generating materials can be used alone or in combination of two or more kinds. As the resin used for the charge generation layer, polyvinyl chloride, polyvinyl acetate, polyester, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polystyrene, polycarbonate, acrylic resin, phenol resin, etc. are used. These resins may be used alone or as a mixture. Solvents for the coating liquid used when forming the charge generation layer from these resins include toluene, methylene chloride, monochlorobenzene, methyl alcohol, ethyl alcohol, ethyl acetate, tetrahydrofuran, cyclohexane and the like. These solvents may be used alone or as a mixture. The thickness of the charge generation layer is 0.05 to 5 μm, preferably about 0.1 to 2 μm.

The charge transfer layer is formed by making the charge transfer material compatible with the resin. The charge transfer material includes an electron transfer material and a hole transfer material. Examples of the electron transfer substance include chloroanil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, and the like. There are substances and those obtained by polymerizing them.

As the hole transfer material, pyrene, N-ethylcarbazole, N-isopropylcarbazole, N-
Methyl-N-phenylhydrazino-3-methylidene-9
-Ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, N, N-
Diphenylhydrazino-3-methylidene-10-ethylphenothiazine, p-diethylaminobenzaldehyde-N, N-diphenylhydrazone, p-diethylaminobenzaldehyde-N-α-naphthyl-N-phenylhydrazone, 1,3,3, -trimethylindo Renin-ω
-Hydrazones such as aldehyde-N, N-diphenylhydrazone, p-pyrrolidinobenzaldehyde-N, N-diphenylhydrazone, p-diethylaminobenzaldehyde-3-methylbenzothiazolinone-2-hydrazone, 2,5-bis ( p-diethylaminophenyl)-
1,3,4-oxadiazole, 1-phenyl-3-
(P-Diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [quinolyl (2)]
-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [pyridyl (2)]-3- (p-diethylaminostyryl) -5-
(P-Diethylaminophenyl) pyrazoline, 1- [6
-Methoxypyridyl (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [pyridyl (3)]-3- (p-diethylaminostyryl) -5- (p- There are pyrazolines such as diethylaminophenyl) pyrazolin, triarylmethane compounds, oxadiazole compounds, thiazole compounds, triphenylamine, poly-N-vinylcarbazole and the like, and these known charge transfer materials may be used alone or in combination.
A combination of two or more species can be used.

As the resin of the charge transfer layer, polystyrene, ketone resin, phenol resin, polyester, polycarbonate, polyvinyl butyral, polyvinyl formal, polyacrylamide, polyamide and the like are used. These resins may be used alone or as a mixture.
Further, various additives usually used for these resins, for example, an ultraviolet absorber, an antioxidant and the like can be appropriately added. Tetrahydrofuran, dioxane, cyclohexane, toluene, dichloroethane, methylene chloride, monochlorobenzene and the like can be used as a solvent for the coating liquid when the charge transfer layer is formed of these resins. These solvents can also be used alone or as a mixture. The thickness of the charge transfer layer is 5 to 40 μm, preferably about 15 to 25 μm.

As the coating method for forming the photosensitive layer using the coating liquid, known methods such as a spin coater, an applicator, a spray coater, a bar coater, a dip coater and a doctor blade are used. The applied photosensitive layer is dried by heating with hot air, infrared rays or the like.

[0016]

EXAMPLES Next, examples of the present invention will be described in detail.

[Example 1] 3% by weight of titanyl phthalocyanine and 2% by weight of butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) were placed on an aluminum cylinder having a diameter of 80 mm and an anodized film having a thickness of about 10 μm. Disperse and dissolve in tetrahydrofuran, silicone oil (SH21
PA, manufactured by Toray Dow Corning) for solid content of 500
The coating solution added with ppm was applied by dip coating, and then dried by heating to form a charge generation layer having a thickness of about 0.2 μm. Next, the charge transfer substance (M) represented by the structural formula 1 and the polycarbonate resin (Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) (B) were used in a weight ratio of M / B = 0.8 and a solid content concentration of 25% by weight. A coating solution dissolved in methylene chloride was applied onto the charge generation layer by dip coating, and then dried by heating to form a charge transfer layer having a thickness of about 20 μm to prepare an electrophotographic photoreceptor. The charge transfer material of Formula 1 is 1,1-bis (P-diethylaminophenyl)-
It is 4,4-diphenyl-1,3-butadiene.

[0018]

The electrophotographic photosensitive member was mounted on a page printer and evaluated for continuous printing of 60,000 pages. Further, the adhesion strength was evaluated by the JISK5400 cross-cut tape method. Simply speaking of this board tape method,
This is an evaluation method in which the photosensitive film of the photoconductor is cut into a grid pattern with a cutter, the tape is adhered to the film surface, and then the amount of the film attached to the tape is expressed by points when the tape is peeled off.

[Example 2] The amount of silicone oil added was 1
A sample was prepared and evaluated in the same manner as in Example 1 except that the content was changed to 000 ppm.

[Example 3] The amount of silicone oil added was 5
A sample was prepared and evaluated in the same manner as in Example 1 except that the content was changed to 0 ppm.

Comparative Example 1 A sample was prepared and evaluated in the same manner as in Example 1 except that silicone oil was not added.

[Comparative Example 2] The addition amount of silicone oil was 1
A sample was prepared and evaluated in the same manner as in Example 1 except that the content was changed to 0000 ppm.

Example 4 3% by weight of titanyl phthalocyanine and 2% by weight of butyral resin (BX-1, Sekisui Chemical Co., Ltd.) were placed on a 30 mmφ aluminum cylinder having an anodized film having a thickness of about 10 μm on tetrahydrofuran. After being dispersed and dissolved in, a commercially available silicone oil was added to the solid content in an amount of 500 ppm, and a dip coating was performed.
It was heated and dried to form a charge generation layer having a thickness of about 0.2 μm. Next, a charge transfer material (M) represented by Structural Formula 2 and a polycarbonate resin (Z-200, manufactured by Mitsubishi Gas Chemical Co., Inc.)
(B) and (B) in a weight ratio of M / B = 0.8 and a solid content concentration of 25% by weight, a coating solution dissolved in methylene chloride is applied onto the charge generation layer by dip coating, and then dried by heating to a thickness. About 20μ
A charge transfer layer of m was formed to prepare a photoconductor for electrophotography. The charge transfer material of formula 2 is 1-P-dibenzylaminophenyl-1-P-diethylaminophenyl-4,4-
It is diphenyl-1,3-butadiene.

[0025]

The electrophotographic photosensitive member is mounted on a contact type charging system (brush charging) laser printer, and is mounted on the laser printer.
The continuous printing of 00 sheets was evaluated.

[Example 5] An X-type metal-free phthalocyanine (P) and a charge transfer material (M) represented by the structural formula 3 were placed on a 30 mmφ aluminum cylinder having an anodized film with a thickness of about 10 μm. Polyester resin (Vylon 200, manufactured by Toyobo) (B) in a weight ratio of P / M / B =
2/1/2, dispersed and dissolved in a tetrahydrofuran / toluene (1/1) mixed solution so that the solid content concentration is 25% by weight, and silicone oil (SH28PA, manufactured by Toray Dow Corning) is added to the solid content of 500 ppm. The applied coating solution was applied by dip coating, and then dried by heating to form a photosensitive layer having a thickness of about 20 μm to prepare an electrophotographic photoreceptor. The charge transfer material of Formula 3 is 4-dibenzylamino-2-methylbenzaldehyde-N, N-diphenylhydrazone.

[0028]

The same electrophotographic photosensitive member as in Example 4 was evaluated for continuous printing.

[Comparative Example 3] A sample was prepared and evaluated in the same manner as in Example 4 except that silicone oil was not added.

Comparative Example 4 A sample was prepared and evaluated in the same manner as in Example 5 except that silicone oil was not added.

The above Examples 1, 2, 3, 4 and Comparative Example 1,
The results of Nos. 2, 3 and 4 are shown in Table 1.

[0033]

[Table 1]

[0034]

As described above, in the electrophotographic photoreceptor according to the present invention, by adding silicone oil to the layer in contact with the support whose surface is anodized, the adhesion of the film is improved and the repetition is improved. The film will not peel off during use and will have sufficient durability. The electrophotographic photosensitive member can be easily manufactured by the method for manufacturing an electrophotographic photosensitive member in which the layer in contact with the support is formed of a coating solution containing silicon oil.

Claims (6)

[Claims] 1. An electrophotographic photoreceptor comprising a photosensitive support comprising a single or a plurality of layers formed on a conductive support whose surface is anodized, wherein the layer in contact with the support contains silicone oil. A photoreceptor for electrophotography, which is characterized by: 2. The electrophotographic photosensitive member according to claim 1, wherein the layer in contact with the support is a charge generation layer obtained by mixing the silicone oil, the resin, and the charge generation material. 3. The electrophotographic photosensitive member according to claim 1, wherein the layer in contact with the support is a charge transfer layer obtained by mixing the silicone oil, a resin, and a charge transfer material. 4. A method for producing a photosensitive layer of an electrophotographic photosensitive member, which is characterized in that a photosensitive layer coating material containing silicon oil is applied to a conductive support whose surface is anodized to form an electron. A method for producing a photosensitive layer of a photographic photoreceptor. 5. The method for producing a photosensitive layer of an electrophotographic photoreceptor according to claim 4, wherein the photosensitive layer coating material is a coating liquid containing a charge generation layer, the silicone oil and a resin. 6. The electron according to claim 5, wherein the amount of the silicone oil in the coating liquid is 50 to 1000 ppm in weight ratio with respect to an element forming a layer in contact with the support. A method for producing a photosensitive layer of a photographic photoreceptor.