JPH03267166A - Coating vessel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Al Industrial Field of Application) This invention relates to a coating container for containing a coating liquid and applying coating to the surface of a substrate.

(bl) Conventional technology As a method of forming a coating film on the surface of a substrate, conventionally, the substrate is immersed in a coating liquid stored in a coating tank (coating container), pulled up, and dried. The coating method was common.In the dip coating method, the entire substrate is immersed in the coating tank at once. The coating of the substrate can be done at the same time, allowing for mass production.

Recently, a method has also been developed in which a coating film is formed on the surface of a substrate by passing the substrate through the inner diameter side of a ring-shaped coating container containing a coating liquid.

This latter coating method is also used, for example, when forming a photoresist film on a cylindrical substrate of a photoreceptor, and the coating is performed as follows.

The inner diameter side of the ring-shaped coating container is set horizontally.
Instead of the wall, a spacer, which will be described later, is in close contact with a ring-shaped blade provided on the inner diameter side of the bottom surface of the coating container, and contains the photosensitive liquid. The spacer supports the cylindrical substrate to be coated from above and below. Further, the lower spacer is pushed up along with the cylindrical base almost perpendicularly to the axial direction using a push-up jig.
It passes through the ring of the ring-shaped coating container from bottom to top. As a result, the upper spacer, which served as the inner wall of the ring-shaped coating container, moves upward, and the outer peripheral surface of the cylindrical base set underneath comes into direct contact with the photosensitive liquid. In this state, the cylindrical substrate is pushed upward, and a photosensitive liquid is applied to the outer peripheral surface of the cylindrical substrate to form a photosensitive film. When the coating of the cylindrical substrate is completed, the spacer under the cylindrical substrate is fixed to the inner diameter side of the ring-shaped coating container and acts as a wall.
Contains photosensitive liquid.

As described above, in a coating device using a ring-shaped coating container, the amount of coating liquid, especially the amount to be discarded, is small and the coating efficiency is relatively high, and the device is small and costs can be reduced.

(C1 Problem to be solved by the invention) However, in all of the above-mentioned methods, there is a problem that the concentration and viscosity of the coating liquid tend to change within the coating container.The coating liquid becomes concentrated due to evaporation of the solvent from the coating liquid. As a result, the density and viscosity change over time, and the thickness of the formed coating film differs each time.Therefore, the photoreceptor, which is a product, has its electrophotographic properties, especially chargeability, sensitivity, This affects the residual potential and increases the variation.

In particular, when applying a charge generation layer and a charge transport layer to a substrate by passing the substrate through a photosensitive liquid in a ring-shaped coating container, the amount of coating liquid per substrate is extremely large, as it is several ml. Since the amount of fresh liquid refilled per hour is also small.

Therefore, the problem of the above-mentioned negative effects is serious.

Therefore, an object of the present invention is to provide a coating container in which the concentration and viscosity of the coating liquid contained therein do not change.

(Means for Solving Problem d1) In this invention, a coating liquid is stored, a substrate to be coated in the coating liquid is coated, and the coating liquid is replenished in order to maintain a constant liquid amount. The coating container is characterized in that the mouth is provided sufficiently below the level of the coating liquid when the amount of the coating liquid decreases, and the outlet is provided at approximately the level of the liquid when the constant amount of liquid is stored.

(e) Effect: In the coating container according to the present invention, new coating liquid is supplied from the replenishment port provided sufficiently below the liquid level when the coating liquid decreases so that the amount is larger than the fixed amount required for coating. do. Then, new coating liquid enters from the bottom of the coating container and the old coating liquid at the top rises, and especially the upper layer of the coating liquid, where the concentration and viscosity have increased due to the explosion of solvent, rises above the level of the constant liquid volume. The liquid then flows out from the outlet provided at the liquid level of a certain amount. In other words, the concentration and clay of the coating liquid are kept constant by replenishing the adjusted new coating liquid, overflowing the coating liquid, and discharging the part where the concentration and viscosity have changed. No variation in film thickness occurs. Therefore, for example, in the case of coating the substrate of a photoreceptor, the thickness of the photoresist film becomes constant, the electrophotographic characteristics of the photoreceptor are stabilized, and image quality is not adversely affected during image formation.

(f) Embodiment diagram is a schematic diagram of a photoreceptor coating apparatus to which a coating container according to an embodiment of the present invention is applied.

The coating container unit 10 is ring-shaped, and the cylindrical substrate 30 of the photoreceptor to be coated passes through the inner diameter side of the ring. A blade 3 is provided on the bottom of the coating liquid pan (coating container in this embodiment) 1 in a portion that comes into close contact with the cylindrical base.
The blade 3 is fixed by a blade holder 3a. A replenishment port 1) for replenishing new coating liquid is provided at the lowest part of the wall of the coating liquid pan 1. Further, a discharge port 12 is provided at a position approximately at the liquid level when a constant amount of liquid is required. A replenishment pipe 17 is connected to the replenishment port 1) to a tank 18, and a pump 16 is used to replenish the photosensitive liquid. A discharge pipe 13 is connected to the discharge port 12 and reaches a tank 14 . A pipe 19 pumps the photosensitive liquid from the tank 14 to the tank 18.
Circulate by 5. A lid 2 is provided above the liquid coating plate 1, and an opening 2a having an outer diameter slightly larger than the outer diameter of the cylindrical base body and a stirring hole for setting two stirrers 4 are provided in the center of the M2. 2b is formed. The ring-shaped liquid coating plate 1 does not have a wall on the inner diameter side, and instead, the cylindrical base body 30 slides on the blade 3 and accommodates the photosensitive liquid 20,
During the coating operation, the cylindrical base 30, the liquid applicator 1, M2, and the blade 3 constitute the coating container UNINO 1-10. The cylindrical substrate to be coated does not constitute the coating container unit 10 before or after the coating operation, and the spacer 5a or 5b on either the upper or lower side of the cylindrical substrate 30 is in close contact with the blade for coating. A construction container unit 10 is configured.

The coating container unit 10 is fixed to a frame 8 below its outer periphery. The spacer char 7 serves to fix the upper and lower spacers 5a or 5b in a predetermined position. A push-up jig 6b of the push-up device 6 is provided below the lower spacer 5b. In the push-up device 6, a feed screw 6a is connected to the push-up jig 6b from below, and rotation of a motor 6c is transmitted through a gear portion 6e. The push-up device 6 uses a push-up jig 6b to cause the lower spacer 5b and the cylindrical substrate 30 set therein to pass through the photosensitive liquid (coating liquid of this embodiment) 20 contained in the coating container unit 10. As a result, the cylindrical substrate 30 comes into direct contact with the photosensitive liquid 20, and a photosensitive film 21 is formed.

A San-7 S1 is attached to the upper part of the push-up jig 6b, and a sensor S2 is attached at a position below the coating container unit 10 corresponding to the San-7 S1 at the position where the spacer is fixed. When the push-up device 6 pushes up the cylindrical substrate and the lower spacer 5b comes to a predetermined position in the coating container unit 10, the coating of the cylindrical substrate is completed. At this time, the positions of sensor S1 and sensor S2 are perfectly aligned, and sensor S2 detects sensor S1 and turns on. Conversely, when the push-up jig descends to set the next cylindrical base, sensor S2 does not detect sensor S1 and is turned off. Based on the detection timing of the sensor, the photosensitive liquid in the coating container unit 7) is replenished and stirred between coating operations.

That is, the photosensitive liquid 2o whose concentration and viscosity have been adjusted is placed in the tank 18.
From there, it is supplied to the supply port 1) by pump ↓6. At this time, if you replenish the photosensitive liquid in excess of the certain amount required for coating, the liquid level of the photosensitive liquid in the coating container will rise, and the photosensitive liquid in the upper layer, which has a higher concentration and viscosity, will be drained. It rises above the position of the outlet 12 and is discharged from the outlet 12 through the discharge pipe 13 into the tank 14 . Thereafter, stirring is performed in the coating container, and in the tank 14, solvent is added and stirred by a viscosity control device (not shown), and the mixture is returned to the tank 18 through the vibrator 19.

In this example, as a photosensitive liquid (coating liquid), 2 parts by weight of dibrom anthron and butyral resin (Eslesoc BM.
2, Sekisui Chemical) 2 parts by weight, cyclohexanone 23
0 parts by weight was prepared and dispersed in a ball mill for 8 hours, and the viscosity was 6.
cP's was used. By replenishing excess new solution and overflowing it between coating operations, the viscosity of the photosensitive solution did not change significantly over time and remained stable at around ±0.5 cP. Moreover - the amount of coating used on cylindrical substrates is always 0.05 g/n? A photoreceptor with a stable photoresist film thickness can be formed before and after the photoreceptor.

In this example, the application was applied to a coating device that uses a ring-shaped coating container unit.
Even when applied to other areas, it can be coated with a photosensitive liquid that always has a stable density and viscosity.

(G1 Effects of the Invention As described above, according to this invention, when the coating liquid decreases, new coating liquid can be supplied from the replenishment port provided sufficiently below the liquid level in an amount larger than the fixed amount required for coating. In this way, the coating liquid whose concentration and viscosity have changed due to evaporation of the solvent is overflowed from the discharge port provided at the top, and the coating liquid whose concentration and viscosity have changed is replenished accordingly. However, the concentration and viscosity of the coating liquid changes, so the concentration and clay of the coating liquid are kept constant.Therefore, there is no variation in the thickness of the coating film, for example, when coating the substrate of a photoreceptor. , the thickness of the photoresist film becomes constant, and a photoreceptor having stable electrophotographic properties can be manufactured.

[Brief explanation of drawings]

The figure is a schematic configuration diagram of a photoconductor coating apparatus to which a coating container according to an embodiment of the present invention is applied. 1-liquid coating device (coating container of this example), 1)-supply port, 12-discharge port, 20-photosensitive liquid (coating liquid of this example), 30-cylindrical substrate (this example) ).

Claims (1)

[Claims] (1) A replenishment port for storing the coating liquid and applying the coating to the substrate to be coated in the coating liquid, and for replenishing the coating liquid to maintain a constant liquid level, is provided to reduce the liquid volume of the coating liquid. What is claimed is: 1. A coating container which is provided sufficiently below a liquid level when a certain amount of liquid is stored, the coating container being provided with a discharge port substantially at a liquid level when a certain amount of liquid is stored.