JPH05142789A - Method for removing coating film of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obviate the generation of defects in the coating film of an electrophotographic sensitive body by preventing the bouncing back of the hair tips of a brush at the time of removing the unnecessary coating film at the bottom end of the photosensitive body in the production stage of the electrophotographic sensitive body. CONSTITUTION:A brush device 5 for removing the coating film constituted by providing a plate 52 for preventing the bouncing back of the hair tips of the brush so as to cover the brush at the top end of a supporting member 51 supporting the brush is rotated in the circumferential direction of the electrophotographic sensitive drum in the state of maintaining the contact of the brush with the bottom end of the electrophotographic sensitive drum and the coating film is removed by drawing the electrophotographic sensitive drum upward at the time of removing the coating film of the electrophotographic sensitive body formed by a dip coating method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing an unnecessary coating film at the time of manufacturing an electrophotographic photosensitive member. More specifically, after forming a photosensitive layer by a dip coating method, an unnecessary portion of the lower end portion of the electrophotographic photosensitive drum is formed. The present invention relates to a method for removing a coating film from an electrophotographic photosensitive member, which is improved so that the coating film will not be defective due to the bristles of the brush repelling when the coating film is removed.

[0002]

2. Description of the Related Art In an electrophotographic photosensitive member, an intermediate layer is optionally provided on a conductive substrate, and then a photosensitive layer is formed.
When such an electrophotographic photosensitive member is used in a copying machine, a laser printer or the like, the distance between the electrophotographic photosensitive member and the developing roll must be always kept constant in order to improve the developing performance. Therefore, usually, a method such as applying a roller to the end portion of the electrophotographic photosensitive member or holding it by coloring is adopted. In this case, since the roller and the portion in contact with the coloring ring are subject to rubbing, there is a problem that the photosensitive layer is unevenly peeled or worn when the photosensitive layer is present. Therefore, it is necessary that the photosensitive layer is not formed in that portion. Among the coating methods conventionally used for forming a photosensitive layer and the like, the dip coating method in which a substrate is dipped in a coating liquid and then the substrate is pulled up to apply the coating liquid is a substrate of any shape, particularly a cylindrical substrate. Since it is possible to form a coating film having a constant film thickness on the surface of No. 1, it is suitable for manufacturing an electrophotographic photosensitive member. In that case, it is possible to easily expose the upper end of the substrate so as not to form a coating film by adjusting the dipping height of the substrate, but the lower end is soaked in the coating solution. , A coating layer is formed. Therefore, the coating layer formed on the lower end must be removed after coating.

Conventionally, in order to remove the coating layer at the lower end of the substrate, for example, as disclosed in JP-A-59-142555, a method of removing by ultrasonic waves, JP-A-60-97861. As described in the publication, a method of peeling with a brush, and a method of removing with a scraping member, as described in JP-A-61-2222571, are known. Among these methods, a brush method is preferable as a method that can be easily and cleanly removed without disturbing the boundary surface.

[0004]

However, in the brush device used conventionally, generally, as shown in FIG. 5, the fibers 52 for the brush are bristled in the planting holes provided in the support member 51. Has been formed. When such a brush device is scraped by rotating the brush device in the circumferential direction of the electrophotographic photosensitive drum 1 by using a removing device as shown in FIG. When pulling out the body drum, as shown in FIG. 6, the bristle tips of the brush are dragged by the electrophotographic photosensitive drum and lifted (5
3) There is a problem in that when the hair ends come off the electrophotographic photosensitive drum, the surface of the solvent 7 in the container storage tank 6 is repelled and the solvent 7 splashes, causing a defect on the surface of the coating film 2. The present invention has been made to remedy the drawbacks caused by such conventional brushes. That is, an object of the present invention is to provide an improved method for removing a coating film from an electrophotographic photosensitive member, which prevents the coating film from being defective due to the bristles of the brush rebounding.

[0005]

As a result of intensive studies, the present inventor has found that the above object can be achieved by providing a brush bounce prevention plate on the upper end portion of the brush support member, and completed the present invention. Came to do. That is, the electrophotographic photosensitive coating film removing method of the present invention, when removing the electrophotographic photosensitive coating film formed by the dip coating method, the brush of the brush so as to cover the brush at the upper end of the supporting member that supports the brush. The brush device for removing a coating film provided with a bristling bounce prevention plate is rotated in the circumferential direction of the electrophotographic photosensitive drum in a state where the brush is in contact with the lower end portion of the electrophotographic photosensitive drum. It is characterized in that the coating film is removed by pulling upward.

The present invention will be described in detail. Figure 1
It is a schematic block diagram of the coating film removal apparatus for implementing this invention. In the figure, reference numeral 1 denotes a drum-shaped substrate on the surface of which an electrophotographic photoreceptor coating film 2 is formed, which is supported by a support member (not shown) so as to be movable in the vertical direction. The solvent storage tank 6 is filled with the solvent 7, and a plurality of, for example, 2 to 4 brush devices 5 are arranged. The brush device has the structure shown in FIGS. 2 and 3. That is, the brush device includes a brush support member 51, a brush 52,
It is composed of prevention plates 54 and 55 for preventing the bristles of the brush from rebounding. 2 shows the case where the prevention plate 54 is a flat plate, and FIG. 3 shows the case where the claw 56 is attached to the lower end of the tip of the prevention plate 55. A support member 51 that supports the brush is rotatably supported by a rotating device (not shown).

In the above brush device, the length of the protruding portions of the prevention plates 54 and 55 is preferably set to be slightly shorter than the length of the brush. Further, the claw 56 is set so as to always hold a part of the brush. Further, as the material of the brush, nylon, polyethylene, polypropylene, polyester, etc. are suitable. The size of one hole for brushing the brush is about 0.5 to 2 mm, and the distance between the holes is about 1 to 3 mm. The entire width of the brush is preferably used in correspondence with the width of the coating film to be removed.

Regarding the electrophotographic photosensitive drum on which the coating film is formed by the dip coating method, when the coating film is removed by using the above coating film removing device, the electrophotographic photosensitive drum is lowered and the lower end portion thereof is lowered. Is immersed in a solvent and brought into contact with the brush.
The brush device is arranged in the circumferential direction of the electrophotographic photosensitive drum,
It is rotated at a speed of 50 rpm, which causes the peeling of the coating film. The operation time is usually preferably 5 to 60 seconds.
The brush device may be disposed inside the electrophotographic photosensitive drum, but it can be omitted if it is not necessary to remove the coating film inside the electrophotographic photosensitive drum. The solvent used may be the same as that used for the coating liquid for forming the coating film. Further, any material can be used as long as it has solubility in the coating film.

[0009]

In the present invention, even if the brush device is rotated in the circumferential direction of the electrophotographic photosensitive drum 1 and scraped by using the removing device as shown in FIG. 1, the bristles of the brush are prevented from rebounding. As a result of the plate being pressed by the plate, when the electrophotographic photosensitive drum is pulled out after completion of the removing work as in the conventional brush device, as shown in FIG. 6, the bristle tips of the brush are dragged by the electrophotographic photosensitive drum. Lift (5
3) When the hair tips come off, the surface of the solvent 7 is not repelled and the solvent 7 does not splash. Further, when the bristles bounce prevention plate of the brush having the claws 56 is provided, the claws 56 are set so as to always hold a part of the brush, so that the bounce prevention effect is enhanced.

[0010]

EXAMPLES The present invention will be described below with reference to examples. Example 1 An aluminum pipe having an outer diameter of 84 mm, an inner diameter of 82 mm and a length of 310 mm was used as a substrate, and a coating layer was formed so that the aluminum pipe was exposed by 10 mm from both ends. That is, as the coating liquid, a copolymer nylon resin (trade name: CM
8000 (manufactured by Toray Industries, Inc.) 8 parts (parts by weight, the same applies hereinafter) were dissolved in 60 parts of methanol and 40 parts of butanol. Using this, it was applied by the dip coating device shown in FIG.

In FIG. 7, reference numeral 12 is a coating tank, which is filled with the coating liquid 9. Coating liquid 9 is pump 10
It is pressurized with and is supplied to the coating tank 12 through the filter 11. 13 is a float for preventing foaming during application.
The conductive substrate 1 is attached to the support 14 and can be moved up and down by the rotation of the screw screw 15.
The application was performed by immersing the aluminum pipe to a height of 10 mm from the upper end and then pulling it up at a speed of 100 mm / min. After coating, there was a small amount of liquid pool in the lower part of the substrate, and the coating liquid invaded the back side up to about 10 mm from the bottom and was wet.

After air-drying for about 3 minutes, the film was treated with a coating film removing device having a brush device without a bristling bounce prevention plate. Using butanol as a solvent, a brush device equipped with a polyester brush is arranged so as to make contact with the inside and outside of the aluminum pipe, and 5 seconds per 15 seconds.
It was rotated and extracted. After that, when the aluminum pipe was pulled up at a speed of 100 mm / min, the splashing of the brush caused the solvent to scatter, causing several spots on the coating film. Next, replace the brush device with one having a prevention plate 55 having a claw 56 as shown in FIG.
When the same extraction operation was performed, there was no brush rebound, and thus a good coating film without defects was obtained.

[0013]

According to the present invention, an undesired coating film on the lower end portion of the electrophotographic photosensitive member is removed at the time of manufacturing the electrophotographic photosensitive member by using the brush device provided with the brush bounce prevention plate of the brush. When the photoconductor drum is pulled out, the bristle tips of the brush are not dragged by the electrophotographic photoconductor drum and lifted. Therefore, when the hair tips come off, the surface of the solvent 7 is not repelled and the solvent 7 does not splash, and a high-quality electrophotographic photosensitive member having no coating film defects can be manufactured.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a coating film removing apparatus used in the present invention.

FIG. 2 is a cross-sectional view of one example of a brush device used in the present invention.

FIG. 3 is a cross-sectional view of another example of the brush device used in the present invention.

FIG. 4 is a vertical cross-sectional view (a) and a horizontal cross-sectional view (b) of a coating film removing device using a conventional brush device.

FIG. 5 is a perspective view of a conventional brush device.

FIG. 6 is a diagram illustrating a rebounding state when a coating film removing device using a conventional brush device is used.

FIG. 7 is a schematic configuration diagram of a dip coating device for forming a photosensitive layer and the like.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base | substrate 53 ... Brush lifting 2 ... Coating film 54,55 ... Prevention plate 3 ... Exposed part 56 ... Claw 5 ... Brush device 6 ... Solvent storage tank 51 ... Brush support member 7 ... Solvent 52 ... Brush

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[Procedure amendment]

[Submission date] December 14, 1992

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

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[Figure 5]

[Figure 6]

[Figure 7]

Claims (1)

[Claims] 1. A coating comprising a brush tip bounce prevention plate provided on the upper end of a supporting member for supporting the brush so as to cover the brush when removing the electrophotographic photoreceptor coating formed by the dip coating method. The film removing brush device is rotated in the circumferential direction of the electrophotographic photosensitive drum in a state of being in brush contact with the lower end of the electrophotographic photosensitive drum, and the coating film is removed by pulling out the electrophotographic photosensitive drum upward. A method for removing an electrophotographic photoreceptor coating film, which comprises: