JPH05224437A - Base body for electrophotographic sensitive body and surface treatment therefor - Google Patents

Abstract

PURPOSE:To perform the removal of contaminant and roughening of the surface of a base body in one process with excellent safeness without causing an environmental problem and to prevent the formation of interference fringes due to laser light. CONSTITUTION:Fine frozen particles obtd. by freezing water vapor are sprayed on the surface of a base body to remove contaminants on the surface and to roughen the surface of the base body. Formation of interference fringes due to laser light can be prevented in the electrophotographic sensitive body using the base body subjected to this surface treatment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for an electrophotographic photoreceptor and a surface treatment method therefor, and particularly, without using a Freon-based cleaning liquid or a chlorine-based cleaning liquid such as trichloroethane,
The present invention relates to a surface treatment method for a substrate capable of removing contaminants and roughening the surface to produce a photoreceptor for a laser printer that does not generate interference fringes.

[0002]

2. Description of the Related Art Electrophotographic photoreceptors are widely used in electronic copying machines, printers, etc. Among them, organic photoreceptors having a photosensitive layer formed by coating are advantageous in terms of cost. These electrophotographic photoreceptors usually use a cylindrical body made of aluminum as a substrate, but in that case, defects in the coating film formed on the substrate cause image defects or decrease in adhesion. Sometimes. Therefore, it becomes important how the coating liquid can be uniformly coated on the substrate without any defects. By the way, since aluminum kerosene or the like is usually attached to the aluminum substrate in the processing step, conventionally, these stains are washed by the following method. That is, (1) a method of degreasing the aluminum substrate surface with an alkali, washing with water, and then drying with Freon vapor, (2) a method of performing Freon cleaning and then drying with Freon vapor,
(3) After washing with 1,1,1-trichloroethane (hereinafter referred to as trichloroethane), there is a method of drying with trichloroethane vapor, but in many cases, Freon vapor is used in the final drying step. ing. However, all of the above-mentioned conventional cleaning methods have the following problems, and are not always satisfactory and optimum methods. That is, (1) it is difficult to remove contaminants of minute deposits due to solvent cleaning, and (2) chlorine-based solvents such as Freon-based or triethane (1,1,1-trichloroethane) are used. There were problems such as being unfavorable. On the other hand, in a laser printer, since the laser light is monochromatic light, it may interfere with the surface of the photoconductor to produce a light stripe pattern, and therefore, the electrostatic latent image formed by the laser light also has a stripe pattern. However, there is a problem that a light and shade stripe pattern appears during copying. Regarding this point, conventionally, (1) an anodized layer is formed on the surface of the substrate to scatter laser light, (2) a specific light absorption layer is formed on the surface of the photoconductor, and the laser light is absorbed (3 ) A method of scattering laser light by subjecting the surface of the substrate to a honing treatment (for example, JP-A-3-64762).
Is proposed. However, even in these methods, complicated processing is required in the working process, and there is room for improvement in cost. On the other hand, it is known that cleaning is performed by using frozen fine particles of water vapor (for example, Japanese Patent Laid-Open No. HEI-1).
No. 155168 and No. 3-180035), it is not known that a substrate for an electrophotographic photoreceptor is roughened simultaneously with cleaning.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to improve the problems in the prior art. That is, an object of the present invention is to provide an electrophotographic substrate capable of preventing the formation of interference fringes due to laser light. Another object of the present invention is to provide a surface treatment method for an electrophotographic substrate, which can remove contaminants and roughen the surface in one step. Still another object of the present invention is to provide a method for surface treatment of an electrophotographic substrate which is excellent in safety without causing environmental problems.

[0005]

The above object of the present invention can be achieved by spraying fine frozen particles obtained by freezing steam onto the surface of a substrate. That is, in the electrophotographic photoreceptor substrate of the present invention, by spraying fine frozen particles obtained by freezing steam onto the substrate surface, contaminants on the substrate surface are removed and the substrate surface is roughened. Is characterized by. In the present invention, it is preferable that the surface-treated electrophotographic photosensitive member substrate is then immersed in ion-exchanged water and dried.

The present invention will be described in detail below. FIG. 1 is a schematic configuration diagram of a substrate surface treatment apparatus for carrying out the present invention. This substrate cleaning apparatus is configured to remove contaminants on the surface of a cylindrical substrate and simultaneously roughen the surface of the substrate. In FIG. 1, 1 is a cylindrical base made of aluminum or the like, which is rotatably supported, and 2 is an injection nozzle, which is installed so as to be movable in parallel with the cylindrical base. Also, 5 is a frozen particle tank, 7
Is a spray nozzle, and 8 is an ion exchange water tank. The ion-exchanged water is stored in the ion-exchanged water tank 8 from the pipe 9 in advance, and the pressurized gas from the pipe 10 causes the ion-exchanged water to be sprayed from the spray nozzle 7 in the form of water vapor. At the same time, liquid nitrogen is introduced from the pipe 6 to freeze the ion-exchanged water in the state of water vapor, and the fine frozen particles 3 are obtained. The frozen particles are collected in the frozen particle tank 5. The frozen particles are jetted from the jet nozzle 2 to the surface of the substrate by using the jet gas from the pipe 4 as a carrier gas. Thereby, the contaminants on the surface of the substrate are removed, and at the same time, the surface of the substrate is roughened by the compositional deformation. Therefore,
When the photosensitive layer is formed on the surface of the treated substrate, the laser light is scattered on the surface of the substrate, and it becomes possible to prevent the generation of interference fringes due to the laser light.

FIG. 2 is a schematic diagram of a post-treatment apparatus for immersing the cylindrical substrate surface-treated as described above in ion-exchanged water and drying it. Ion-exchanged water is introduced into the drying tank 11 through the pipe 9 and is heated to 50 to 60 ° C. by the heater 13. The ion-exchanged water is refluxed via the filter 14 by the liquid feed pump 12. By immersing the surface-treated cylindrical substrate 1 in ion-exchanged water in a drying tank and pulling it up at a constant speed, the surface of the liquid surface is dried by the residual heat of the cylindrical substrate.

[0008]

EXAMPLES The present invention will be described in detail below by showing Examples and Comparative Examples of the present invention. All "parts" mean parts by weight. (Example) An aluminum pipe (A1050) having a thickness of 1 mm, a diameter of 84 mm, and a length of 340 mm was prepared, and the aluminum pipe (A1050) was cut by a mirror lathe using a diamond tool to finish the surface into a smooth surface of Ra: 0.04 μm. It was Frozen particles of ion-exchanged water were sprayed onto the surface of this aluminum pipe using the substrate surface treatment device shown in FIG. 1 to perform surface treatment. The processing conditions in that case were as follows.
Frozen particle size: 60 μm (d32), injection gas pressure: 4.
0 kg / cm ² G, injection angle: 90 ° with respect to the tangential line and the axial direction of the aluminum pipe, injection distance: 30 mm,
Rotational speed of aluminum pipe: 300 rpm, jet nozzle moving speed: 120 mm / min. Then, it was dipped and dried by the post-treatment device shown in FIG. In that case, the temperature of the ion-exchanged water is 50 ° C and the pulling speed is 300 m.
m / min. The amount of oil remaining on the aluminum pipe surface-treated as described above is 0.25 to 0.84 μ.
g / cm ² , surface roughness: Ra is 0.22 to 0.2
It was 5 μm.

Using the above aluminum pipe as a substrate, an undercoat layer, a charge generation layer and a charge transport layer were formed by a dip coating method to prepare an electrophotographic photoreceptor having a three-layer structure. That is, the undercoat layer was applied to 8-nylon resin (trade name: laccamide, manufactured by Dainippon Paint Co., Ltd.) using a mixed solution of methanol / butanol, and after natural drying, 1
It was formed by drying at a drying temperature of 00 ° C. for 10 minutes. The charge generation layer was formed as follows. That is, polyvinyl butyral resin (trade name: BM1, manufactured by Sekisui Chemical Co., Ltd.)
1 part was dissolved in 60 parts of cyclohexane, 1 part of vanadyl phthalocyanine was added thereto, and the coating solution obtained by dispersion treatment with a sand mill was applied and dried at a drying temperature of 120 ° C. for 10 minutes to give a film thickness of 0.8 μm. The charge generation layer of was formed. The charge transport layer was formed as follows. That is,
4 parts of N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine and 6 parts of polycarbonate Z resin were added to 36 parts of monochlorobenzene. The coating solution thus obtained was dissolved and dried at a drying temperature of 120 ° C. for 60 minutes to form a charge transport layer having a film thickness of 20 μm. When a copying operation was carried out using this electrophotographic photosensitive member using a laser printer, no interference fringe pattern was observed.

Comparative Example The same aluminum pipe as in the above example was washed with trichloroethane, then with Freon and dried. Next, a wet honing process was performed with an apparatus as shown in FIG. In FIG. 3, reference numeral 1 denotes a base, which is rotatably mounted. Reference numeral 15 is an abrasive recovery tank in which the abrasive 17 is recovered. The abrasive dispersed in the ion-exchanged water 16 is
It is supplied to the injection nozzle 2 by the liquid feed pump 12, and is injected onto the surface of the substrate 1 by the injection gas from the pipe 4.
In addition, 9 is a piping for supplying ion-exchanged water.
The wet honing treatment conditions were as follows. Alundum (trade name: Alundum # 400, manufactured by Showa Denko KK) was used as an abrasive. Substrate pressure for injection is 1.5k
g / cm ² G, the injection angle was 90 ° with respect to the tangential line and the axial direction of the aluminum pipe, the injection distance was 30 mm, the rotation speed of the aluminum pipe was 100 rpm, and the injection nozzle moving speed was 540 mm / min. Then, the treated aluminum pipe was washed with deionized water and Freon and dried. The amount of oil remaining on this surface-treated aluminum pipe was 0.25 to 1.13 μg / cm ² , and the surface roughness: Ra was 0.14 to 0.22 μm. Using the aluminum pipe whose surface was roughened as described above, an electrophotographic photosensitive member having a three-layer structure was produced in the same manner as in the above example. When a copy operation was performed using a laser printer using this electrophotographic photoreceptor,
No interference fringe pattern was observed.

As is clear from the comparison between the above-mentioned examples and comparative examples, the examples of the present invention have the same amount of oil remaining on the surface of the substrate as the comparative examples, and the surface roughening The degrees were almost similar, and they could be sufficiently used as substrates for electrophotographic photoreceptors. Therefore, according to the present invention, cleaning with trichloroethane as in the above comparative example,
Further, it is possible to produce an electrophotographic photoreceptor having the same effect as the conventional one without requiring a pretreatment step such as cleaning with Freon and without requiring a cleaning step with Freon after the surface treatment. is there.

[0012]

Since the present invention has the above-mentioned structure, it is possible to remove the contaminants from the surface of the substrate and to roughen the surface of the substrate in one step, which is in contrast to the conventional technique. The number of steps can be reduced and the production cost can be reduced. Moreover, it is excellent in safety without causing any environmental problems. Further, the electrophotographic photosensitive member formed using the electrophotographic substrate surface-treated according to the present invention does not generate an interference fringe pattern due to a laser Punter or the like.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a substrate surface treatment apparatus for carrying out the present invention.

FIG. 2 is a schematic configuration diagram of a post-processing device.

FIG. 3 is a schematic configuration diagram of a conventional wet honing processing apparatus.

[Explanation of symbols]

1 ... Cylindrical substrate, 2 ... Injection nozzle, 3 ... Frozen particles, 5 ...
Frozen particle tank, 7 ... Spray nozzle, 8 ... Ion exchange water tank, 11 ... Drying tank, 12 ... Liquid feed pump, 13 ... Heating heater, 14 ... Filter.

Claims (3)

[Claims] 1. A substrate for an electrophotographic photoreceptor, which has been surface-treated by spraying fine frozen particles obtained by freezing water vapor onto the surface of the substrate. 2. An electrophotographic photosensitive member characterized by spraying fine frozen particles obtained by freezing water vapor onto a substrate surface to remove contaminants on the substrate surface and roughen the substrate surface. Substrate surface treatment method. 3. The method for treating the surface of a substrate for an electrophotographic photosensitive member according to claim 2, wherein the substrate is immersed in ion-exchanged water and dried after the injection of the fine frozen particles.