JPS6161672A - Coating method - Google Patents

Abstract

PURPOSE:To execute uniform coating with high production efficiency and high accuracy by moving vertically one of plural vessels connected to each other by a communicating pipe with respect to the other and making movable a coating liquid by a level fall type. CONSTITUTION:The vessels 1, 1' attached with materials 2, 2' to be coated on a stage 10 are so positioned that the vessel 1' side is positioned below and after the coating liquid is poured into the vessel 1', a driving part 6 is started to revolve counterclockwise a gear 3 by which the vessel 1' is so moved as to be positioned above the vessel 1 via a vessel supporting member 9. Then coating liquid 8 in the vessel 1' flows into the vessel 1 by passing through the communicating pipe 4 as the vessel 1' ascends, by which said liquid is coated to the material 2'. The coated material 2' is taken out and the fresh material to be coated is attached thereto, then the gear 3 is rotated this time in the clockwise direction to execute wating to the material 2 in the vessel 1 and the same operation is repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION (b) Field of Industrial Application The present invention relates to a coating method and an apparatus therefor, and more particularly to a coating method and an apparatus therefor which can efficiently carry out dip coating.

(Powder) Conventional technology and its problems In the conventional dip coating method, the object to be coated is immersed in a coating solution filled in advance in a container, and then pulled up and applied. There is a difference in the film thickness between the upper and lower parts, which is thinner at the top and thicker at the bottom, and uneven coating tends to occur due to the vibration of the lifting means when lifting the object to be coated, making it difficult to get a uniform coating. It has the disadvantage that it is difficult to obtain a film.In addition, in the conventional dip coating method, in order to increase the production efficiency, it is possible to support a large number of objects to be coated with a support member, immerse them in the coating liquid at once, and then pull them up. However, it is inevitable that the equipment will become complicated and large.

In addition to the above-mentioned method of pulling up the object to be coated from the coating liquid, the dip coating method includes a method of drawing out the coating liquid from a container in which the object to be coated is immersed. This method is superior to the above-mentioned dip coating method in that it is possible to obtain a uniform coating thickness by controlling the rate of descent of the coating liquid level when the coating liquid is drawn out from the container. are doing. However, on the other hand, it is cumbersome to have to refill the container with the coating solution after the coating solution is removed from the container, and there is a waste of time required to fill the container with the coating solution, resulting in poor production efficiency. When withdrawing the coating liquid from the coating liquid, it is necessary to use a control device such as a flowmeter to control the rate of descent of the coating liquid level.

Furthermore, a liquid pump is usually used to draw out the coating solution and send it to the container, but bubbles are generated during the liquid transfer, and these bubbles adhere to the object to be coated and cause the surface to be coated. It has the disadvantage of disturbing the homogeneity, and in order to avoid this it is necessary to wait for the bubbles to disappear, but this causes a problem of wasting time and reducing production efficiency.

(Q. Purpose of the Invention The purpose of the present invention is to solve the above-mentioned production efficiency problems and adverse effects on the coating layer, and to provide a coating method that has high production efficiency and enables uniform coating with high precision.

■ Structure of the Invention An object of the present invention is to fix an object to be coated in at least one of the plurality of containers connected by a communication pipe so that the coating liquid can move between the plurality of containers; By moving one up and down, the coating liquid is caused to move between the containers, and after filling the container in which the object to be coated is fixed with the necessary amount of coating liquid, the coating liquid is removed. This is achieved by a coating method characterized in that the coating liquid is transferred to another container to form a coating film on the surface of the object to be coated.

■　Example Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows an example of the coating method according to the present invention, and FIG. 2 is a top view of FIG.

(1) and (1') are containers used to store the coating liquid (8) and are used for coating. (2)
, (2') are the objects to be coated, which in this example are cylindrical cylinders, and the same cylindrical cylinders will be used in Figures 3 and 4 below, where only the outer peripheral surface of the objects will be coated. (
10) is a mounting table on which a cylindrical cylinder is fixed. The mounting table (10) is tapered and the opening of the cylinder is pushed into it and fixed.

(4) is a communication pipe connected to containers (1) and (1') so that the coating liquid can freely flow between them. (
9) t, use the container support rod (container support side) attached to the bottom back side of the container (1) to move the top and bottom of the container 4. It is equipped with an elevating leg structure that allows for crocodile movement. (6) is a drive unit, that is, a motor, which is capable of forward and reverse rotation. (3) is a gear that is rotated by being transmitted from the drive unit (6) via 4 [1 (71). When this gear (3) rotates, rotation is applied to the container support member (9). Transmission 9: If the container (1) rises, the volume d (4') will fall.

To explain the operation procedure of the apparatus 1'' according to the example of FIGS.
) on each of the objects (2) and (2') to be coated!
When the container (1) (1') is attached to the i-base and the coating is started from the position shown in Fig. 1, the container (1')
After pouring and filling the coating g (δ), the drive unit (6) is started, the gear (3) is rotated counterclockwise, and the container support side (9) is advanced to position the container (1). By rotating the container (one position and up and down reversed),
The liquid (8) in the pot 21j flows into the trough (11) through the communication pipe (4) as the container (1') rises, so that the object to be coated (2
') can be applied. He was painted! Remove the cloth ((c) and attach a new object to be coated. Next, rotate the gear (3) clockwise and attach the new object to be coated (2).
) and repeating this operation, it is possible to continuously coat the object to be coated. In order to prevent the coating liquid from running out, the container can be provided with a coating liquid replenishment port at the bottom of the container. (Not shown) FIGS. 3 and 4 are examples in which only one container is moved up and down to coat the object. (5) is a coating liquid storage container that stores the coating liquid. Although not shown below the container support member (9) in FIGS. 3 and 4, there is provided an elevating mechanism that is movable up and down via a drive section.

In FIG. 3, the object to be coated is coated by moving the coating liquid storage container (5) up and down. To explain the operating procedure, the coating liquid storage container (5) is positioned lower than the container (1), and the object to be coated (2) is attached to the mounting table (10). After that, when the drive unit is started and the coating liquid storage container (5) is raised through the container support member (9), the coating liquid (8) is sent to the container (1) through the communication pipe (4). The ascent is stopped when the container has been filled with the necessary amount of coating liquid. Then, the drive unit is started again and the coating liquid storage container (5) is lowered through the container support member (9) to a position lower than the position of the container (1).
The coating liquid (8) in ) is returned to the coating liquid storage container (5), so that the object to be cleaned (2) is coated.

In Fig. 4, the object to be coated is coated by moving the container (9) up and down.To explain the operating procedure, the container (1) is placed at a higher position than the coating liquid storage container (5). Let me,
Attach the object to be coated (2) to the mounting table α■.After this, start the drive unit and move the object (2) to the container (1) through the container support member (9).
The coating liquid (8) in the coating liquid storage container (5) is sent to the container (13) through the communication pipe (4), and the coating liquid is lowered at the point where the necessary groove is filled in the container. Then, when the drive unit is started again and the container (1) is raised through the container support member (9) to a higher position than the coating liquid storage container (5), the coating liquid (8) is raised. ) is returned to the coating liquid storage container (5), so that the object to be coated (2) is coated.

The material used for the device of the present invention is not particularly limited, but
The inside of the container and the inside of the communication pipe, which are in contact with the coating liquid, preferably have excellent solvent resistance. Furthermore, the communication pipe is preferably made of soft resin, rubber, etc. that allows the bending position of the pipe to change as the application container or the liquid storage container moves up and down, and the internal volume of the pipe can be adjusted so that the moving speed of the application liquid does not change greatly. The inner diameter of the communicating pipe is not particularly limited, but it is usually about 5.
It is about ~20a+. It is preferable that the object-to-be-coated table in the container has a structure that allows the object to be coated to be fixed so that it does not move during coating. For example, in the case where the object to be coated is a cylindrical cylinder, metal or hard resin may be used for the tapered mounting table mentioned above, but it is better to use elastic resin or rubber so that the coating liquid can penetrate inside the cylinder. This is preferable because it is difficult to do.

Next, an example will be described in which an electrophotographic photosensitive drum is manufactured by applying an electrophotographic coating liquid to a cylindrical cylinder.

A cylindrical cylinder was coated using a coating apparatus similar to that shown in FIG. The coating was applied only to the outer peripheral surface of the . As a result of coating at a rising and falling speed of the coating container of 0.54 m/-, a uniform coated layer with a solid content of 12 η was obtained.

In the present invention, the number of containers used for coating is appropriately determined depending on mass productivity.

[F] Effects of the invention According to the present invention, the following effects can be obtained.

(1) The coating method uses a liquid level drop method to obtain a uniform coating film.

(2) Since the liquid level drop control is performed by moving the container up and down, a complicated control device is not required.

(3) Since the coating liquid is moved between coating containers, the extraction and supply of the coating liquid can be performed at the same time, eliminating wasted time and improving production efficiency.

(4) Since there is no need to use a liquid pump to move the coating liquid, troubles due to the generation of bubbles can be prevented.

(5) It is not affected by the shape of the object to be coated and is suitable for coating on spherical or cylindrical substrates.

(6) Suitable for manufacturing electrophotographic photosensitive drums that require uniform coating film.

[Brief explanation of the drawing]

1, 3, and 4 are schematic diagrams showing examples of the coating method and apparatus of the present invention, and FIG. 2 is a schematic diagram of FIG. 1 viewed from above. (1), (f) Coating container (2), (z) Object to be coated (3) Gear (4) Communication pipe (5) Coating liquid storage container (6) Drive unit (force shaft
(8) Coating liquid (9) Container support member Ql Mounting table Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) An object to be coated is fixed in at least one arbitrary container connected by a communication pipe so that the coating liquid can be transferred between the plurality of containers, and at least one arbitrary one of the plurality of containers is moved up and down. By this, the coating liquid is caused to move between the containers, and after filling the container in which the object to be coated is fixed with the necessary amount of coating liquid, the coating liquid is extracted and the coating liquid is transferred to another container. A coating method characterized by forming a coating film on the surface of an object to be coated.