JPH04344650A - Method for recycling substrate of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To recycle the substrate of the electrophotographic sensitive body and to reduce its manufacturing cost by removing its photosensitive layer from a used or off-grade body having the conductive substrate anodized on the surface and again forming the photosensitive layer. CONSTITUTION:The photosensitive layer is removed from the used or off-grade electrophotographic sensitive body 1 having the conductive substrate anodized on the surface, for example, by bringing a cylindrical brush 2 rotating around a shaft 2a as a center into contact with the surface of the photosensitive body 1 rotating around a shaft 1a as a center in the same direction as the brush 2, ejecting a solvent for dissolving a resin constituting the photosensitive layer from shower nozzles 4, and brushing the surface of the photosensitive layer in the presence of the solvent 3. Since the surface of the conductive substrate is not scratched, the photosensitive layer comprising an electric charge generating layer and a charge transfer layer is again formed on this conductive substrate.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recycling an anodized (alumite) conductive substrate of a used or defective electrophotographic photoreceptor.

0002

[Prior Art] In recent years, the lifespan of photoreceptors used in image forming devices such as copying machines and laser printers has been extended, and they can now be used for a longer period of time than before, but they still need to be replaced almost regularly.・It is a consumable item that should be discarded. In addition, performance has improved and OPC (organic photoconductor) photoreceptors have become widely used, but they are still consumable items that must be replaced or discarded. Moreover, not only when the photoconductor reaches the end of its lifespan, but even before its lifespan, if it deteriorates to the point where it affects image quality, it is replaced and treated as a used photoconductor.

[0003]Furthermore, photoreceptors that are found to have image defects such as white spots or black spots or coating defects in the inspection process before being shipped to the market, or have problems in electrical characteristics are treated as defective products.

0004

Conventionally, used photoreceptors that have been replaced and photoreceptors that are found to be defective due to image defects, etc., have been discarded without being reused. That is, it is impossible to remove the photosensitive layer from the surface of a photoreceptor substrate (conductive substrate) used for copying machines without damaging the surface, and removing the photosensitive layer may affect the image quality of the conductive substrate. A conductive substrate with such scratches cannot be reused as a photoreceptor substrate as it is. Furthermore, since the thickness of the conductive substrate is approximately 1 to 3 mm, it is difficult to cut away any scratches that occur. Therefore, conventionally used or defective electrophotographic photoreceptors have been discarded without being reused.

In addition, photoreceptor substrates mainly used for laser printers are anodized (anodized) for the purpose of roughening the surface, that is, providing a blocking layer on a conductive gas substrate. However, these conductive substrates are currently being discarded without being reused.

[0006] In order to produce an organic photoreceptor, polishing of the raw tube,
It requires many steps such as cleaning, coating the charge generation layer, coating the charge transport layer, and assembling the flange, making it relatively expensive in terms of manufacturing cost. Therefore, in order to reduce manufacturing costs, materials costs, manufacturing process costs, labor costs, etc. are being reviewed.

[0007] In particular, the proportion of the conductive substrate in the material cost is high, and it is desired to reuse the conductive substrate in consideration of reducing manufacturing costs and saving resources.

[0008]

[Means for Solving the Problems] As a result of intensive research by the present inventors, the surface of the anodized (alumite) treated substrate is hardened (30 HV for the aluminum substrate, 200 to 400 HV for the alumite treated product) ) Therefore, even if the photosensitive layer is wiped from the substrate surface with a brush or cloth impregnated with a solvent that can dissolve the resin forming the photosensitive layer, the resulting conductive substrate will not be damaged. It was discovered that by forming a photosensitive layer again on the surface of a conductive substrate, an electrophotographic photoreceptor having excellent image-forming ability can be obtained, and based on this knowledge, the present invention was accomplished.

[0009]

[Function] The structure of the present invention is to reapply the photosensitive layer to the surface of the conductive substrate obtained after removing the photosensitive layer from a used or defective electrophotographic photoreceptor whose surface has been subjected to anodic oxidation (alumite) treatment. This is a method for recycling an electrophotographic photoreceptor by coating a photosensitive layer. The method for removing the photosensitive layer from the electrophotographic photoreceptor is not particularly limited, and any known method can be applied.

The removal method will be explained using a brush cleaning method.

The photosensitive layer of a used or defective electrophotographic photosensitive member is removed by brush cleaning. Figure 1 shows an outline of brush cleaning. A used or defective electrophotographic photoreceptor 1 rotates around an axis 1a, and its surface is in contact with a cylindrical brush 2 that rotates around an axis 2a. A solvent for dissolving the resin forming the photosensitive layer is sprayed onto the electrophotographic photoreceptor 1 and the cylindrical brush 2 from a surrounding shower nozzle 4 . Electrophotographic photoreceptor 1 and cylindrical brush 2
are rotated in the same direction and the photoreceptor layer is removed by brushing in the presence of a solvent.

The brush-cleaned electrophotographic photoreceptor substrate is
After performing ultrasonic cleaning in an organic solvent bath heated to 40 to 80°C, the electrophotographic photoreceptor substrate is immersed in an organic solvent cold bath of 19 to 23°C, and then placed in a vapor bath of organic solvent heated to the boiling point. Insert, steam clean, and dry.

Solvents for dissolving the resin forming the photosensitive layer used in the present invention include chlorine-based solvents such as 1,1,1-trichloroethane, trichlorethylene, and perchlorethylene, and fluorine-based solvents such as Freon-112. Examples include solvents and alcohols such as isopropyl alcohol. As the organic solvent used for ultrasonic cleaning, cold bath, and steam cleaning, the above-mentioned solvents can be used, and it is preferable to use the same solvent as the one that dissolves the resin forming the photosensitive layer.

An example of the conditions for each step is shown below.

(1) Brush cleaning Brush rotation speed: 60 to 100 rpm Photoreceptor rotation speed: 60 to 100 rpm Cleaning time: 30 seconds to 3 minutes (2) Ultrasonic cleaning bath temperature: 20 to 80°C Immersion time: 30 seconds to 3 minutes (3) Cold bath temperature: 15 to 30°C Immersion time: 30 seconds to 3 minutes (4) Steam cleaning cleaning time: 30 seconds to 3 minutes (5) Drying temperature: 60 to 130°C Drying time: 30 A conductive substrate subjected to anodization (alumite treatment) obtained by a method that takes a second to three minutes or more can be reused as a photoreceptor substrate for electrophotographic photoreceptors and laser printers. It is possible to reduce manufacturing costs.

[0016]

[Examples] The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples.

EXAMPLE A used electrophotographic photoreceptor was cleaned with a brush as shown in FIG. 1 using 1,1,1-trichloroethane as a cleaning solution, and
, ultrasonic cleaning in a 1,1-trichloroethane hot bath, 2
immersed in a 1,1,1-trichloroethane cold bath at 0°C;
Steam cleaning in 1,1,1-trichloroethane vapor, 9
It was dried at 0°C for 60 seconds. The conditions for the photosensitive layer removal step are as follows.

(1) Brush cleaning cleaning liquid: 1,1,1-trichloroethane Brush rotation speed:
100 rpm Photoconductor rotation speed: 50 rpm Cleaning time: 60 seconds (2) Ultrasonic cleaning Cleaning liquid: 1,1,1-trichloroethane Cleaning liquid temperature: 6
0°C Immersion time: 60 seconds Ultrasonic wave: 28KHz (3) Cold bath liquid: 1,1,1-trichloroethane Immersion time: 60 seconds (4) Steam cleaning Cleaning liquid: 1,1,1-trichloroethane Cleaning time: 60
On the surface of the conductive substrate from which the second photosensitive layer has been removed, the following solution A is dip-coated using a known dipping method to a dry film thickness of 0.4 μm, and dried at 80°C for 30 minutes to form a charge-generating layer. Further, the following liquid B was applied by dip coating on the surface of the substrate coated with liquid A so that the film thickness after drying was 17 μm.
A charge transport layer was formed by drying at ℃ for 1 hour.

When the obtained electrophotographic photoreceptor was mounted on a predetermined laser printer and used, it was possible to obtain a good image quality free of image defects such as interference unevenness, white streaks, black streaks, and white spots.

Liquid A: 2 parts by weight of ε-type copper phthalocyanine (Liophoton EPPC, manufactured by Toyo Ink Co., Ltd.), 1 part by weight of butyral resin (S-LEC BL-1, manufactured by Sekisui Chemical Co., Ltd.), and 100 parts by weight of tetrahydrofuran. A liquid obtained by dispersion treatment in a ball mill for 8 hours. B liquid butadiene charge transport material (1,1-bis(p-
diethylaminophenyl)-4,4-diphenyl-1,
Obtained by dissolving 1 part by weight of 3-butadiene (manufactured by Takasago Fragrance Co., Ltd.) and 1 part by weight of polycarbonate resin (Panlite L-1225, manufactured by Teijin Kasei Ltd.) in 10 parts by weight of dichloromethane. liquid.

[0021]

[Chemical formula 1]

[0022]

[Effects of the Invention] As described above, by the method of the present invention, it is possible to reuse used or defective electrophotographic photoreceptors that were conventionally disposed of, and it is possible to reduce the manufacturing cost in photoreceptor manufacturing. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of brush cleaning according to the present invention.

[Explanation of symbols]

1 Used electrophotographic photoreceptor 2 Cylindrical brush 4 Shower nozzle

Claims (1)

[Claims] Claim 1: The photosensitive layer is removed from a used or defective electrophotographic photoreceptor whose conductive substrate surface has been anodized, and a photosensitive layer consisting of a charge generation layer and a charge transport layer is reattached to the obtained conductive substrate. 1. A method for recycling an electrophotographic photoreceptor substrate, comprising: