JPS60244363A - Coating apparatus - 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 Field of the Invention The present invention relates to a coating device, and more particularly, to a coating device for continuously coating an outer peripheral surface of a cylindrical body with an electrophotographic photoreceptor on a load. 〇(B) Conventional technology and four-point method for coating the outer circumferential surface of a substrate to be coated, such as a cylindrical body, with a spray method, a dipping method, and a manual method using a ring-shaped liquid container. Various methods are known, such as a coating method, a curtain coating method, a blade coating method, a roll coating method, and an extrusion method.

However, while the spray method is excellent in mass production, it has the drawbacks of a small amount of coating per application, poor surface smoothness, and a wide range of film thickness from 1 μm to several tens of μm and an extremely high surface finish. It is not suitable as a coating method for electrophotographic photoreceptors that require a smooth coating layer. The dipping method is a relatively simple method, but there is a large difference in film thickness between the upper and lower parts of the cylindrical body, and when coating two or more layers, it is difficult to coat each layer with the same solvent system. The disadvantage is that the lower layer is likely to be doubled, and furthermore, mass productivity is poor.

The ring coating method shown in JP-A-53-22544, JP-A-56-101149, JP-A-58-11064, JP-A-58-180261, etc. has excellent surface smoothness of the coating layer, and also shortens the contact time with the coating liquid. Because it is short, it has the advantage of being suitable for multilayer coating. In the ring coating method, an elastic ring with an inner diameter slightly smaller than the outer diameter of a cylindrical body is integrated with an outer cylinder of a liquid container, and the cylindrical body is passed through this ring to coat the outer surface of the cylindrical body. The coating solution is supplied to the coating chamber formed by the above method, and is applied to the outer surface of the cylindrical body by moving and cooling either the cylindrical chamber or the ring, or both. However, this ring coating method was unsuccessful because it was difficult to coat a large number of cylindrical bodies in succession due to the structure of the apparatus. For example, unless the first cylindrical body and the second cylindrical body are completely joined without any gaps and passed through the ring, the coating chamber will not be formed and the coating liquid will leak out and cause the second cylindrical body to pass through the ring. This results in contamination. Furthermore, when the cylindrical body is supplied by the lower lifting means and the cylindrical body is passed through the application ring and discharged by the upper lifting means, during the transfer from the lower lifting means to the upper lifting means, both lifting means are The speeds must match exactly. Also,
When the first cylindrical body and the second cylindrical body are joined, the speeds of the two cylindrical bodies must be perfectly matched, otherwise an impact will occur during joining, resulting in disturbance of the coated surface. It is from. In addition, if the joint is not precise enough to be considered as a single cylindrical body, liquid will accumulate at the mismatched part of the joint, and this pool will drip onto the outer surface of the second cylindrical body. This may disturb the coated surface or penetrate into the inner surface of the joint and stain the inner surface of the second cylindrical body.

Furthermore, it is known to provide an intermediate ring between the first cylindrical body and the second cylindrical rest for the purpose of preventing the coating from being disturbed when coating the laminated photoreceptor, but this 9. It has the same drawbacks as mentioned above ◇ In addition, the ring coating method uses only the coating liquid above the tip of the elastic ring, so the amount of coating liquid is small (on the other hand, as mentioned above, the contact time with the cylindrical shape is short). In order to perform continuous coating, the coating liquid must be supplied intermittently, making it impossible to obtain a uniform coating surface due to the generation of bubbles and fluctuations in the liquid level, and reducing production efficiency. (Q. Purpose of the Invention The purpose of the present invention is to provide an electrophotographic photosensitive material that is capable of efficiently and continuously forming a uniform coating layer on the outer peripheral surface of a cylindrical shape, despite the drawbacks mentioned above. An object of the present invention is to provide a coating device suitable for coating the body.

(D) Structure of the Invention The present invention comprises an elevating means for elevating a cylindrical base material to be coated, a mounting table 2 for an outer circular body provided in the elevating means, and a member for holding the outer circumference of the outer circular body. This is a coating device used in a ring coating method, characterized in that both sides of the outer circular body including a stop means form a continuous outer circumferential surface when attached to the inner surface of a cylindrical body. In addition to the above-mentioned characteristics, the coating device of the present invention has a feature that allows the coating liquid in the container to overflow so that the coating liquid can be continuously supplied to the ring-shaped liquid container even while the outer circular body is stopped by the locking means. This includes devices configured as follows.

(B) Example The operation and mechanism of the coating apparatus of the present invention will be explained in detail below with reference to the drawings.

FIGS. 1(a) to 1(a) are cross-sectional views showing over time the state in which the outer circumferential surface of a cylindrical body is coated using the coating apparatus of the present invention. The cylindrical body 7 passes through the liquid container 4 having an elastic ring and is applied while being raised at a constant speed by means of a lifting device (only the rod 6 is shown). Ring-shaped liquid container 4
is provided with a coating liquid supply pipe l, and the coating layer is automatically sent from the coating liquid supply pipe to the liquid container 4 by a pump (not shown) for coating. 2
In this case, a liquid storage tank 2 is connected to the ring-shaped liquid container 4 separately through a communication pipe 3 (also referred to as a coating liquid supply pipe), and a coating liquid supply pipe 1 and an overflow pipe 5 are provided in this liquid storage tank 2. ing. Providing the overflow pipe 5 and the liquid storage tank 2 separately from the liquid container 4 makes it easy to manufacture the device, and prevents the liquid level from flowing into the overflow pipe in the vicinity of coating a cylindrical body. This is to prevent localized unevenness due to turbulence, etc., but if the outer diameter of the liquid container 4 is increased, the overflow pipe 5 can be provided inside the liquid container 4 without providing a separate liquid storage tank. Coating onto the outer circumferential surface of the cylindrical body 7 is carried out at the liquid level of the coating plate # above the tip of the elastic ring, and the height of the liquid level can be set arbitrarily. In the illustrated coating device of the present invention, the liquid level is determined by the overflow tube, and the inlet of the overflow tube 5 is located slightly above the tip of the elastic ring.

is also possible.

Consumption type (coating amount) in a cylindrical shape from the coating liquid supply pipe l
Although a somewhat larger amount of coating liquid is continuously supplied, the level of the coating liquid does not fluctuate even when the cylindrical body moves.
It can be applied under the same conditions all the time. Further, even while the outer circumferential circular body 9 is stopped in the ring container by the locking means 1O for holding it, the application liquid can be similarly supplied. Figure 1 (&) shows the state before coating on the cylindrical body 7, and continuous coating work is performed on the outer circular body 9I.
It is preferable to start with the ring container stopped by the locking means 10.

The lifting device is provided with a mounting table 8 for the outer circular body 9, and holds the outer circular body 9. The outer circular body 9 may be hollow or non-hollow as long as it has the same outer diameter as the cylindrical body and has a circular outer periphery. The upper side of the outer circumferential body 9 held on the mounting table 8 (FIG. 1(a)) Id is inserted and attached to the inner surface of the cylindrical body 7 as a substrate to be coated, and at that time, the cylindrical body 7 and the outer circumference The outer diameter is reduced by an amount equal to the outer wall thickness of the cylindrical body 7 so that the outer circumference of the circular body 9 forms a continuous outer circumferential surface. However, that part does not need to be endless.

The outer circumferential circular body 9 is formed after the application of the cylindrical body 7 is completed.
Since it is in the same state as I, its lower side (Fig. 1(a)) must also have the same structure as the upper side described above.Both sides of the outer circular body 9 have the structure described above. The present invention is not limited to this, and when inserted into a cylindrical body, it may be attached to the inner surface of the body using an expansion spring method. The mounting table 8 holds the outer circular body 9. Therefore, the mounting table 8 is as shown in Fig. 1 (
As shown by &), the outer diameter of the lower side of the outer circular body 9 is also a cylindrical body with a slightly larger inner diameter (the outer diameter can be set arbitrarily). It can also be a cylindrical body or a cylindrical body with an outer diameter slightly smaller than the inner diameter of 9.

The lifting device includes means for lifting and lowering at a constant speed. The means for raising and lowering may be any known method, such as a motor, a hydraulic cylinder, a pneumatic cylinder, or the like.

At 2 in FIG. 1(,), the outer circular body 9I held by the locking means 10 is attached to the raised cylindrical body 7. Simultaneously with or after mounting, the locking means 1O is separated from the outer circumferential body 9T so as to release its holding. The cylindrical body 7 is applied while continuing to rise at a constant speed (FIG. 1(b)).

When the outer circular body 9 reaches the position of the outer circular body 9 in FIG. Figure (C)).

Since the cylindrical body 9 has a flow of coating liquid from the outer circular body 9I above it and forms a continuous outer circumferential surface, it is possible to coat the cylindrical body 9 with a uniform film thickness over the entire length.

On the other hand, the cylindrical body 7 that has been coated is discharged together with the outer circular body 9' by the elevating device 11 serving as a discharging means, and the elevating means having the mounting table 8 is lowered to prepare the next cylindrical body ( Figure 1 (C)). The ejection means may be of any known type. ◎ Fig. 2 shows the locking means 10 compared to Fig. 1 (
In the sectional view seen from above in b), there are four locking means (0 locking means), but it is sufficient to have at least two locking means.

The materials of the mounting table 8, the outer circular body 9, and the locking means 10 are metal,
Any material such as plastic may be used.

The outer circle can be reused by removing the paint film. Continuous coating can be performed automatically by using known detection means for raising and lowering the lifting device, operating the locking means, etc.

The viscosity of the liquid applied using the coating device of the present invention can be selected over a wide range, but is usually 0.5 to
Approximately 1,000 centivoise (OP), preferably 1~
It is 5000F.

Using the ring-shaped liquid container of the coating device shown in Fig. 1,
A dispersion liquid with the following formulation was applied onto the outer peripheral surface of a 16111 aluminum pipe (length 33 m). Coating speed I Q NI
L/sec was applied continuously to 30 aluminum tubes by the method described above and dried. Coating film thickness is 20μm
I failed. The coating liquid was constantly fed from the coating liquid supply pipe 1 at a rate of 3 d7 sec. When the potential was measured after drying, there was only a variation in potential within 2% in the circumferential direction and length direction. It was confirmed that the same quality could be ensured with good reproducibility for the shaped bodies.

CF) Effects of the Invention According to the present invention, an extremely uniform coating layer can be formed over the entire length of the cylindrical body. Also, by employing the outer circumferential circular body 2 and its locking means, the operation of the elevating means and the discharging means is controlled. It has become possible to separate reliable and efficient continuous coating, and it has also become possible to continuously supply the coating liquid.

[Brief explanation of drawings]

Figures 1 (a) to (,) are cross-sectional views of the main parts showing a state in which coating is performed using a specific example of the coating device according to the second aspect of the present invention. Figure 2 shows the locking means. A front sectional view showing a specific example is shown below. ◎ l...Coating liquid supply pipe 2...Storage tank 3...Communication pipe 4...Ring Coating container 5... Overflow pipe 6... Rotsu door... Cylindrical body 8... Placement table 9 and 9''... Outer circumference circular body 10...Locking means 11...Ejection means building 1

Claims (2)

[Claims] (1) A lifting means for raising a cylindrical body as a substrate to be coated, a mounting table for the outer circular body provided in the lifting means, and a locking means for holding the outer circumference of the outer circular body, A coating device used in a ring coating method having a structure in which both sides of the ring form a continuous outer circumferential surface when attached to the inner surface of a cylindrical body. (2) The coating device according to claim 1, further comprising means for overflowing the coating liquid.