JPH0934151A - Production of electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the reflection of the interference fringes of an anodically oxidized film in a photosensitive layer and to improve printing quality by bringing an electrode for anodic oxidation into contact with the inside surface of a cylindrical aluminum substrate. SOLUTION: A bar-shaped and U-shaped titanium electrode 7A for anodic oxidation is disposed to face the non-photosensitive layer region of the outside surface of the cylindrical aluminum substrate 5 and brought into point contact, by a spring effect, with the opening end of the inside surface of the cylindrical aluminum substrate 5. The electrode 7A for anodic oxidation is formed by symmetrically coupling the two U-shaped electrodes. In such a case, the contacts of the electrode 7A are disposed in correspondence to the non-photosensitive layer part of the aluminum substrate 5 and, therefore, the interference patterns are not generated in the photosensitive layer even if the interference fringes are generated in the anodically oxidized film. The mounting of the electrode 7A for anodic oxidation is easy if the electrode is formed out of the bar-shaped and U-shaped metal and is brought into point contact with the opening end of the cylindrical aluminum substrate 5. The interference fringes of the anodically oxidized film are generated at the distance furthest from the photosensitive layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an aluminum base for a photoreceptor for electrophotography, and more particularly to a method for anodizing an aluminum base.

[0002]

2. Description of the Related Art Electrophotographic technology has been developed in the field of copying machines, and has recently been applied to laser printers, etc., and boasts image quality, high speed, and quietness that are incomparable to conventional impact printers. , Is spreading rapidly. Photoreceptors used in these devices are formed by providing a photoconductive layer on a conductive substrate. As the photoconductive layer, a material using an organic substance is mainly used, and a function-separated structure is generally used.

FIG. 3 is a sectional view showing a conventional laminated type electrophotographic photoreceptor. The undercoat layer 3, the charge generation layer 2, and the charge transport layer 1 are sequentially laminated on the aluminum substrate 4. The undercoat layer 3 prevents injection of holes from the conductive substrate to improve the charge retention characteristics of the photoconductor, and is of a type using an organic resin typified by polyamide and an anodized film on the surface of an aluminum substrate. There are two types of formation: the latter is generally advantageous in terms of reliability under high temperature and high humidity environment.

In the anodizing treatment of an aluminum substrate, a conductive substrate that has been dimensionally processed and surface-treated is degreased and washed with a commercially available detergent, degreased with an alkaline solution, and then anodized with an acid solution. Next, the porous film formed by washing with water and anodic oxidation is sealed with nickel acetate. FIG. 4 is a perspective view showing an aluminum substrate on which an anodizing electrode in a conventional anodizing process is mounted.

An anodizing electrode 6 is mounted on the inner surface of a cylindrical aluminum substrate 5. The electrode 6 is in point contact with the aluminum substrate. The aluminum substrate 5 with the electrodes attached is immersed in an electrolytic bath 8 for anodic oxidation. FIG.
FIG. 3 is a plan view showing an aluminum substrate immersed in an electrolytic bath. Aluminum is mainly used for the anodizing electrode.

[0006]

However, when the anodic oxidation treatment is performed, the aluminum substrate is oxidized and the anodizing electrode is also oxidized at the same time, and an oxide film is formed on the electrode surface, which deteriorates electrical conduction. Therefore, it is necessary to drop the oxide on the electrode surface every time. In order to reduce this trouble, a titanium electrode is often used, but in this case as well, an oxide film is formed on the electrode surface with repeated use, and the contact resistance increases. As a result, the conditions of anodic oxidation due to the electrolysis of the electrode contact portion are locally different, and the probability of producing concentric interference fringes (unevenness and thickness unevenness of the oxide film) around the contact portion increases. .

When the photosensitive layer is applied in this state, there is a problem that the interference fringe pattern is reflected in the print quality and the print quality is deteriorated. FIG. 6 is a perspective view showing an interference fringe pattern generated on a photosensitive layer of a conventional electrophotographic photoreceptor. The present invention has been made in view of the above points, and an object thereof is to provide an electrophotographic photosensitive member having good printing quality by preventing interference fringes of an anodized film from being reflected on the photosensitive layer.

[0008]

According to the present invention, there is provided a method for producing an electrophotographic photosensitive member comprising an aluminum substrate surface anodized according to the present invention. This is accomplished by bringing the anodizing electrode into contact with the inner surface of the cylindrical aluminum substrate, facing the layer region.

In the above-mentioned invention, the anodizing electrode is a rod-shaped or U-shaped metal, and it is effective to make point contact with the opening end of the cylindrical aluminum substrate by a spring action.

[0010]

The contact of the electrode is provided corresponding to the non-photosensitive layer portion of the aluminum substrate, so that even if interference fringes are generated on the anodized film, no interference fringe pattern is generated on the photosensitive layer. If the anodizing electrode is made of a rod-shaped or U-shaped metal and is brought into point contact with the opening end of the cylindrical aluminum substrate by the spring action, the electrode can be easily attached to the aluminum substrate, and the interference pattern of the anodized film Occurs at the furthest distance from the photosensitive layer.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. It is preferable to perform degreasing cleaning before anodizing the aluminum substrate. In order to enhance the degreasing effect, etching is usually performed with an alkali such as caustic soda, but etching with an acid that does not easily cause large etching pits is preferable. Anodizing is a treatment in sulfuric acid and the concentration of sulfuric acid is 1
The optimum value is 60 to 200 g / l. The temperature during electrolysis is 1
The optimum temperature is 8 to 22 ° C, but 20 ° C or higher is particularly preferable. The amount of aluminum dissolved in sulfuric acid is 10 g / l or less, preferably 3 to 7 g / l. Although it is easy to use nickel acetate as the sealing agent after anodizing, pure water treatment by water quality control is most suitable in terms of quality, and the treatment temperature is preferably 60 to 80 ° C. The treatment time is 5 to 10 minutes, preferably 8 to 10 minutes.
Cleaning after the sealing treatment is preferably performed with a warm pure water shower, but ultrasonic cleaning is more efficient.

When the electrophotographic photosensitive member produced according to the present invention was used for development, an excellent image having good print quality could be obtained. FIG. 1 is a perspective view showing an aluminum substrate on which an anodizing electrode according to an embodiment of the present invention is mounted. FIG. 2 is a perspective view showing an aluminum substrate on which an anodizing electrode according to another embodiment of the present invention is mounted.

The rod-shaped U-shaped titanium anodic oxidation electrodes 7 and 7A were brought into point contact with the opening end of the cylindrical aluminum substrate 5 by a spring action. The anodizing electrode 7A is formed by connecting two U-shaped electrodes symmetrically. Ten anodizing electrodes were set as one rack, and ten racks were manufactured. Using the manufactured rack, 100 aluminum substrates were anodized and sealed.

The cylindrical aluminum substrate mounted on the rack was degreased with a degreasing agent (fine cleaner 315, temperature 50 ° C.) and washed with water to remove the degreasing agent. Thereafter, degreasing was further performed with nitric acid HNO ₃ . Next, electrolytic treatment was carried out in sulfuric acid at a temperature of 20 ° C. for 24 minutes, and washing was performed with pure water. The sealing treatment was performed using nickel acetate (trade name: alumite sealer / Nippon Kagaku Sangyo Co., Ltd.) at a temperature of 70 ° C. for 8.5 minutes, washing with pure water, and further 40 kH in pure water.
It was washed with an ultrasonic cleaner of z for 3 minutes and dried with hot air.

CGL was produced using the obtained aluminum substrate.
(Charge generation layer: X-type metal-free phthalocyanine dispersed in vinyl chloride-vinyl acetate copolymer at a ratio of 1: 1)
Was applied for about 0.2 μm and dried in an oven at 80 ° C. for about 30 minutes. Next, CTL (charge transport layer: a mixture of polycarbonate resin and hydrazone-based conductive material) is about 22 μm.
m coating and drying in a drying oven at 90 ° C. for about 2 hours.

The obtained photoreceptor was left in the dark for 2 days and then anodized, and a printing test was carried out in that order. Comparative Example The anodizing treatment of the aluminum substrate was performed in the same manner as in the example except that the contact of the electrode was provided at a position facing the photosensitive layer using the conventional anodizing electrode.

FIG. 7 is a diagram showing the transition of the interference fringe pattern occurrence rate of the electrophotographic photoconductors according to the embodiment of the present invention and a different example in comparison with the characteristics of the electrophotographic photoconductor according to the comparative example. Is. It can be seen that the electrophotographic photoconductors according to the examples of the present invention and the different examples do not have an interference fringe pattern, whereas the electrophotographic photoconductors according to the comparative examples have an interference fringe pattern.

[0018]

According to the present invention, the anodizing electrode is brought into contact with the inner surface of the cylindrical aluminum substrate so as to face the non-photosensitive layer region of the outer surface of the cylindrical aluminum substrate. Even if interference fringes are generated, no interference fringe pattern is generated on the photosensitive layer, and an electrophotographic photoreceptor having good printing quality can be obtained.

Further, since the rod-shaped or U-shaped metal anodic oxidation electrode is brought into point contact with the opening end of the cylindrical aluminum substrate by the spring action, the electrode can be easily mounted on the aluminum substrate and is used for electrophotography. The productivity of the photoconductor is improved, and the interference fringes of the anodic oxide film are generated at the position most distant from the photosensitive layer, so that the influence on the photosensitive layer is reduced and the area of the photosensitive layer can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view showing an aluminum substrate on which an anodizing electrode according to an embodiment of the present invention is mounted.

FIG. 2 is a perspective view showing an aluminum substrate on which an anodizing electrode according to another embodiment of the present invention is mounted.

FIG. 3 is a sectional view showing a conventional electrophotographic photoreceptor.

FIG. 4 is a perspective view showing an aluminum substrate on which an anodizing electrode in a conventional anodizing process is mounted.

FIG. 5 is a plan view showing an aluminum substrate immersed in an electrolytic bath.

FIG. 6 is a perspective view showing an interference fringe pattern generated on a photosensitive layer of a conventional electrophotographic photoreceptor.

FIG. 7 is a diagram showing the transition of the interference fringe pattern occurrence rate of the electrophotographic photoconductors according to the examples of the present invention and different examples in comparison with the characteristics of the electrophotographic photoconductor according to the comparative example.

[Explanation of symbols]

 1 Charge Transport Layer 2 Charge Generation Layer 3 Undercoat Layer 4 Aluminum Substrate 5 Cylindrical Aluminum Substrate 6 Anodizing Electrode 7 Anodizing Electrode 7A Anodizing Electrode 8 Electrolyte Bath

Claims (2)

[Claims] 1. An electrophotographic apparatus in which an anode electrode is brought into contact with the inner surface of a cylindrical aluminum substrate to form an oxide film on the surface of the substrate by anodizing treatment, and a non-photosensitive layer region is formed at the end of the outer surface of the substrate. A method for producing a photoconductor, comprising forming an oxide film by bringing an anode electrode into contact with the inner surface of a cylindrical aluminum substrate facing the non-photosensitive layer region of the outer surface of the cylindrical aluminum substrate. Body manufacturing method. 2. The manufacturing method according to claim 1, wherein the anodizing electrode is a rod-shaped or U-shaped metal, and is point-contacted with the opening end of the cylindrical aluminum base body by a spring action. Manufacturing method of electrophotographic photoreceptor.