JPS6053676B2 - Rotary painting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention allows paint to flow down onto the surface of an object to be painted while rotating on a flat surface, so that the centrifugal force caused by the rotation of the object causes the paint to fall onto the surface of the object to be painted. It relates to a rotary coating method in which a coating film is formed by diffusing the present invention.

The biggest bottleneck in this type of painting method is the particles and dust that adhere to the surface of the object to be painted, and if these exist, such as when a high degree of decorativeness is required, the point of attachment may be This is because it causes a delta-shaped paint film breakage toward the outer circumference.

In order to avoid the adhesion of dust and dust, the painting work room may be configured as a clean air room, but this requires expensive equipment and is not very efficient as a painting equipment.

Furthermore, even in a clean air room, it is not possible to remove minute dust and dirt that adheres to the surface of the object to be painted before the painting process, and only the dust that falls and adheres during the painting process in the room can be removed. It's just something you get. Particularly, when the object to be painted is a molded product such as a synthetic resin that is easily charged, the adhesion of dust and dirt is noticeable. Although dust and dirt can be easily removed by removing the electrical charge, it is still not possible to remove particles caught in minute irregularities on the surface of the object to be coated. As a result of various research and considerations, the inventor of the present invention came up with the idea that the rotational speed of the object to be coated should be increased, and moreover, the high rotational speed could be increased to 1.
It has been found that it is sufficient to set the thickness to 500 μm or more.

This will be explained below based on the experimental data shown. This experimental data is based on coating object A, which is injection-molded from polycarbonate resin into a substantially disk shape with a wall thickness of 3rr1/m and a diameter of 150 m/m, and a siloxane-based paint with a viscosity of 9 CpS to form a coating film B. It was created by

Further, approximately 1.0 cc of the paint was dropped onto the surface of the object to be painted A which was rotating at an appropriate speed as described below. 1st
In the conditions shown in Figures A and b, the rotational speed of the object to be coated is 500 r'Pm.
Figure 2 A, b to Figure 6 A, b shows the adhesion status of thread dust and particulate dust when the engine speed is set to 500 rpm.
The speed is increased gradually.

As is clear from these, the string dust and grain dust that adhered to the surface at 500 rpm remain attached to the surface of the object to be coated.
It has been coated with coating film B. When the speed is gradually increased to about 1000 r'Pm, thread dust and particulate dust are slightly reduced as shown in Figure 2 A and b, and when the speed is further increased to about 1500 r'Pm, most of the dust is reduced as shown in Figure 3 A and b. The thread dust has been removed or moved to the vicinity of the peripheral edge of the object to be coated A, and some particulate dust remains. This level is acceptable even for objects to be coated that require highly decorative properties. Third
As shown in Figures A and B, as the object continues to rotate and the coating progresses, the threads remaining on the edge of the object begin to flow outward from the edge. This rotation speed is 2000 rpm, 250
When the speed is increased from 0 rpm to 3000 rpm, Fig. 4 A, b
As shown in Fig. 5A and Fig. 6A and b, thread dust and grain dust are both removed. This is because when the rotational speed of the object to be painted exceeds a certain value, threads and particles are forced outward along the surface of the object by the action of centrifugal force and the flow of paint. As a result, it is coated.
It was revealed that the rotation speed of objects is effective in removing dust and dust.

It has also been found that dust and dust floating around during painting are blown away by the wind pressure caused by the rotation of the object and do not adhere to the surface of the object. In addition, the rotation of the object to be painted is 150 degrees, which is satisfactory for the time being, although some dust and dust remain.
It may last until the painting is completed at around 0r'Pm,
Alternatively, coating may be started at a rotational speed of 1500 r'Prn 8 degrees and gradually increased to about 3000 r'Pm.

In addition, when increasing the thickness of coating film B, 1500r
After applying the coating to the entire surface at pm or more, the rotational speed of the object to be coated may be reduced while the paint continues to flow down. As described above, according to the rotary coating method according to the present invention,
By simply rotating the object to be coated at a high speed of 1500 rpm or higher, dust and dust adhering to any object to be coated can be easily removed.

In particular, it is an extremely suitable coating method for base coating and top coating of molded products that form a metal vapor deposited layer, and is also suitable for use in molded products that are easily charged, such as lenses molded with polycarbonate resin or acrylic resin, to provide hardness, weather resistance, and resistance. This is a highly effective method for applying coating agents to improve scratch resistance.

[Brief explanation of the drawing]

The drawings show the rotational speed of the object to be painted and the adhesion status of dust etc. Figure 1 A, b is 500 rpm, Figure 2 A, b
is 1000 rpm1 Figure 3 A, b is 1500 rpm1 Figure 4 A, b is 2000 rpm1 Figure 5 A, b is 2500
r'Pml FIGS. 6A and 6B show the state in which the objects to be coated are rotated at 3000 rpm, respectively. A: Object to be painted, B: Paint film.

Claims (1)

[Claims] 1. By rotating the object on a flat surface and letting the paint flow down onto the surface of the rotating object, the centrifugal force caused by the rotation of the object causes the paint to be applied onto the surface of the object. 1. A rotary coating method in which the coating material is diffused into the coating material, characterized in that the rotational speed of the object to be coated is set to be 1500 rpm or more when the coating material is flowing down. 2. The rotary coating method according to claim 1, wherein the rotation speed of the object to be coated is gradually increased from 1500 rpm. 3. Claim 1, wherein the rotation of the object to be coated is at 1500 rpm or more and after a required period of rotation has elapsed, the speed is reduced to a normal speed while the paint continues to flow down.
Rotary coating method described in section.