JPS63313161A - Method for removing coated film in end part of drum - Google Patents

Abstract

PURPOSE:To surely and completely remove the coated film in the end part of a drum formed with the coated film on the peripheral face thereof in a short period of time by stages for immersing the end part of the drum into a solvent which dissolves the coated film then transferring the drum into water. CONSTITUTION:The solvent in the coated film is dissolved in the water and the coated film is put into the state of being detached in the form of a film from the outside peripheral face of the drum 10 formed with the coated film over the entire range of the outside peripheral face when the end part of said drum is immersed into the solvent which has an excellent hydrophilic property and dissolved the coated film. The end part of the drum is then immersed into the water 21 in a container 20 through the aperture 23a of a blade 23 having the diameter slightly smaller than the outside diameter of the drum by which the aperture 23a is brought into sliding contact with the outside peripheral face of the drum and the coated film is scraped down. The number of the times to replace the solvent is, therefore, decreased and the coated film in the end part is surely and completely removed in a short period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to: 1. For example, when manufacturing an electrophotographic photosensitive drum, a coating liquid containing a photosensitive substance is applied to the outer peripheral surface of a cylindrical drum. The present invention relates to a method of forming a coating film using a method of forming a coating film, and then removing the coating film from the end of the drum.

(Prior Art) For example, a method for manufacturing an electrophotographic photosensitive drum by coating a 9-cylindrical drum with a coating liquid containing a photosensitive substance is to immerse the drum in a coating liquid while holding the drum approximately vertically. A commonly used dipping method is to form a coating film with a uniform thickness on the outer peripheral surface of the drum by moving the drum out of the coating liquid at a constant speed in the axial direction.

In an electrophotographic photosensitive drum, in order to fit a flange to the end of the drum or perform conductive treatment on the end of the drum, it is preferable that no coating liquid is applied to the end of the drum. However, in the above-mentioned dipping method, since the drum is held substantially vertically and withdrawn from within the coating liquid, the coating liquid is always applied to the lower end of the drum to form a coating film. For this reason, it is necessary to remove the coating film formed at the end of the drum coated with the coating liquid by the dipping method.

In order to solve such problems, for example,
-170858 discloses that the end of the drum is immersed in a solvent capable of dissolving the coating film formed on the outer peripheral surface of the drum, and a flexible plate is slidably attached to the immersed end of the drum. A method is disclosed in which an unnecessary coating film is removed from the end of the drum.

(Problems to be Solved by the Invention) In the method disclosed in JP-A-60-170858, there is a risk that the coating film components dissolved in the solvent may adhere to the end of the drum immersed in the solvent. be. For this reason, coating components must be removed from the solvent and contaminated solvents must be frequently replaced with uncontaminated ones.

The present invention solves the above conventional problems, and its purpose is to eliminate the need for frequent replacement of solvents, etc.
It is an object of the present invention to provide a method capable of removing the coating film on the end of a drum in a short period of time.

(Means for Solving the Problems) The method for removing a coating film from the end of a drum according to the present invention removes the coating film from the end of the drum having a coating film formed on its circumferential surface by removing a coating film that can dissolve the coating film and has excellent hydrophilicity. and immersion in a solvent.

The method includes the steps of removing the end of the drum from the solvent and immersing it in water, and scraping off the coating film on the end of the drum immersed in water, thereby achieving the above object. .

(Example) The present invention will be described below with reference to an example in which an electrophotographic photosensitive drum is manufactured.

For example, the method for removing a coating film from the end of a drum according to the present invention is as follows.

A coating solution containing a photosensitive substance is applied by dipping,
This is carried out to remove the paint film from the end of the drum, which has a paint film formed on almost the entire outer peripheral surface.

In the method of the present invention, first, the end portion of the drum on which the coating film is formed on substantially the entire outer peripheral surface of the drum is melted.

and immersed in a solvent with excellent hydrophilicity. As this solvent, tetrahydrofuran (TIIF), acetone, etc. are used. Hold the drum approximately vertically in such a solvent, the end with the coating to be removed.

Immerse for about 2 to 6 seconds. As a result, the coating film on the end of the drum immersed in the solvent becomes semi-dissolved.

The end of the drum is then withdrawn from the solvent and the portion immersed in the solvent is immediately immersed in water.

Since the semi-dissolved coating film contains a solvent with excellent hydrophilic properties, the solvent in the semi-dissolved coating film is dissolved in water, and the semi-dissolved coating film is dissolved. be reconfigured to a state in which it is not. At this time, the reconstituted coating becomes film-like.

There is a gap between the outer peripheral surface of the drum and the outer peripheral surface of the drum.

And with the end of the drum immersed in water.

Alternatively, with the end of the drum removed from the water, a flexible plate or the like is brought into sliding contact with the end of the drum in order to scrape off the reconstituted coating film. The reconstructed paint film.

Since it is in the form of a film with a gap between it and the outer peripheral surface of the drum, it can be easily scraped off by sliding a flexible plate or the like into it.

In the method of the present invention, the step of immersing the drum end having a semi-dissolved paint film in water and then scraping off the paint film on the drum end is carried out using, for example, a container shown in FIG. be done. Water 21 is stored in the container 20, and the container 20 is made of a flexible material such as polyethylene or fluororesin so as to have a predetermined distance from the upper surface of the water 21 stored in the container 20. The thickness of the material is 0.
A blade 23 of approximately 5 to 2.0 ms+ is provided. The blade 23 has an opening 23a formed in its center and having an inner diameter slightly smaller than the outer diameter of the drum 10 immersed in the water 21. The outer peripheral portion of the blade 23 is supported by a support 24 attached to the inner peripheral surface of the container 20.

Further, 10 is a drum having a coating film formed on its outer peripheral surface, and the lower end of the drum 10 has already been immersed for about 2 to 6 seconds in a solvent that can dissolve the coating film and has excellent hydrophilic properties. has been done.

The drum 1O, with the coating film at the lower end in a semi-dissolved state, is inserted into the opening 23a of the blade 23, and the lower end, which is in a semi-dissolved state, is immersed in water. in this case.

The outer peripheral surface of the drum 10 comes into sliding contact with the peripheral edge of the opening 23a of the blade 23 when passing through the opening 23a of the blade 23.

The semi-dissolved coating film on the lower end of the drum 10 immersed in water is reconstituted to an undissolved state as described above, and forms a film as shown in FIG. This means that there is a gap.

In this state, the drum 10 is moved upward.

The lower end of the drum 10 immersed in the water 21 is withdrawn from the water 21. At this time, the outer peripheral surface of the drum 10 moves upward while slidingly contacting the peripheral edge of the opening 23a of the blade 23.And, as shown in FIG. 23 because it is strongly abutted against the periphery of the opening 23a.

This film-like coating is scraped off.

In this way, the blade 23 is attached to the container 20 that stores the water 21.
, the paint film on the end of the drum 10 is removed by withdrawing the end of the drum 10 from the water 21.

(Effects of the Invention) As described above, the method for removing the paint film on the drum end of the present invention can reliably remove the paint film on the drum end in a short time.

Moreover, it can be completely removed. Since the solvent in which the end of the drum is immersed only leaves the coating in a semi-dissolved state, the solvent is not contaminated much by the coating components and there is no need to frequently replace the solvent.

Figure 1 is a sectional view showing an example of the implementation state of the method of the present invention, Figure 2 is an enlarged view of the main part thereof, and Figure 3 is an enlarged view of the main part for explaining the operation. .

10...Drum, 20...Container, 21...Water, 2
3...Blade.

that's all

Claims (1)

[Claims] 1. A step of immersing the end of the drum on which a coating film is formed on the circumferential surface in a solvent that can dissolve the coating film and has excellent hydrophilicity; A method for removing a coating film from an end of a drum, the method comprising: removing the drum from the drum and immersing it in water; and scraping off the coating from the end of the drum immersed in water.