JP2002210405A - Color changeover coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color changeover coating method, in which the quantities of each color coating material and a cleaning solvent to be used in a process of applying a plurality of color coating materials with a same spray coater are decreased and which is advantageous in environmental correspondence and cost reduction. SOLUTION: In performing the color changeover coating with >=2 kinds of the color coating materials having different colors by the spray coater having a color change valve, after coating the color coating material of each color, the remaining color coating material in the inside of the tip of the coater is extruded with air and/or a solvent from the valve, the inside is cleaned with the solvent and/or air, the extruded coating material and the cleaning liquid are recovered in every coating material of each color and reutilized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention reduces the amount of each color paint and a cleaning solvent (thinner) used in a process of applying a plurality of color paints by the same spray coating machine, thereby reducing environmental requirements and reducing costs. Also useful for a color change coating method.

[0002]

2. Description of the Related Art A color change valve (hereinafter, abbreviated as "CCV") is a color changing device for paints. It is possible to appropriately switch to the color specified for the article to be conveyed by the above. A valve is built in according to the number of colors to be changed, and a cleaning circuit is also provided.

Conventionally, a plurality of coating materials having different colors are applied to objects to be successively conveyed on a conveyor in a coating line by using the CCV in the order of a predetermined color using a CCV. The color change coating method is already known. However, according to this method, for example,
When changing from the colored paint A to the colored paint B, the colored paint A remaining in the path from the CCV to the spray coater is used.
Since they are discarded together with the cleaning solvent, they have a disadvantage that they are not preferable for environmental measures such as resource saving and are not desirable in terms of cost.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned defects in color change coating using CCV. As a result of intensive studies, it has been found that two or more types of coloring different in color using CCV are used. In order to paint the paint sequentially,
After the coating of the colored paint of each coating color is completed, the paint remaining inside the tip of the coating machine from the valve is extruded with air and / or a solvent, and then the inside is washed with a solvent and / or air, and these components are washed. It has been found that the object can be achieved by collecting the extruded paint and the washing liquid for each colored paint and reusing them, and thus completed the present invention.

That is, according to the present invention, two or more kinds of colored paints having different colors are sequentially changed by a spray coater having a color change valve (CCV). The colored paint remaining inside the tip of the coating machine from the valve is extruded with air and / or solvent, and then the interior is washed with solvent and / or air,
The present invention relates to a color change coating method (hereinafter, referred to as “the present method”), in which the extruded paint and the washing liquid are collected for each colored paint of each coating color and reused.

Hereinafter, the present method will be described in detail.

[0007] As the spray coating machine having the color change valve in the present method, a known spray coating machine can be used. Specifically, a plurality of colored paint tanks, a solvent (thinner) tank, a paint pumping section, a solvent pumping section, a CCV
Etc., and a plurality of paint tanks each store color paint having a different color tone according to the purpose, and the paint in each tank is independently pumped to the CCV by a paint pumping unit. I have. An organic solvent-based or water-based colored paint having a desired color tone is CCV.
The valve is opened and closed to be fed to a spray coating machine through a hollow body such as a hose or a pipe.

[0008] In this method, after the colored paint fed from the CCV through the hollow body is sprayed from the spray coater (coating gun) and the coating on the object is completed, the paint is changed to another colored paint (color change). In doing so, the colored paint remaining in the hollow body path from the CCV outlet to the spray coater is extruded with air and / or a solvent, and then the inside of the path is washed with a solvent and / or air, and then extruded. In addition, the colored paint obtained by the washing is recovered without being discarded and reused.

The details of the method will be described with reference to the drawings.

FIG. 1 is a system diagram of an embodiment relating to the present method.

That is, a plurality of colored paint tanks (1),
A solvent (thinner) tank (2), a plurality of paint feeding sections (3), a solvent feeding section (not shown), a CCV (5), and the like are provided. Colored paints having different color tones are stored separately, and the colored paints in each tank are independently pumped to the CCV (5) by the operation of the paint pumping section (3). It is preferable that the coloring paint is an organic solvent-based or water-based liquid paint. Then, the colored paint is pressure-fed to the spray coating machine (7) through a hose or pipe (6) by opening and closing the valve of the CCV (5). In addition, a solvent mixing device (11) is provided on a path from the solvent tank (2) to the CCV (5), and a paint regulator (12) is provided on a path from the CCV (5) to the spray coating machine (7). It is preferable to provide them.

The colored paint a is fed from the CCV (5) and sprayed from a spray coating machine (coating gun) (7), which is applied to an object to be coated (not shown) to perform coating. After the coating is completed, the air and / or the solvent is pumped to the CCV (5) from the air pumping section (13) and remains in the path (6) from the CCV (5) to the spray coater (7). Most of the colored paint a is extruded and discharged out of the system.

The air for extrusion can be pumped by connecting an air compressor (not shown) to the CCV (5), and the solvent can be pumped from the solvent tank (2) through a hose or the like. Via CCV (5)
Can be carried out.

The extrusion of the colored paint a remaining in the path from the CCV (5) to the spray coater (7) is performed by spray coating only air, a solvent only, or a mixed system of air and a solvent from the CCV (5). This is done by forcing the machine (7) into its path, whereby most of the colored paint a remaining in the path is extruded and discharged out of the system. The discharged colored paint a is collected without being discarded as it is.

[0015] The solvent used here is a colored paint a
Preferably, those contained in or compatible with the above are used, and water and an organic solvent are used. The extruded colored paint a is supplied to a branch (14) provided near the spray coater (7).
It is preferable to discharge from the collection tank (15),
Spraying from the spray coating machine (7) and discharge to the outside of the system may be performed. In the case of providing a fork (14) and discharging,
It is preferable to use a dump valve (16).

After extruding the colored paint a in this way,
Further, the colored paint a may remain on the inner walls and corners of the route.
And a solvent and / or air is fed into the passage under pressure to clean the inside. The washing operation can be performed in the same manner as in the extrusion described above.

In the extrusion and washing steps, if the extrusion is carried out only with air, the washing in the next step can be carried out with a solvent alone or with a mixed system of air and solvent, and the extrusion is carried out with a mixed system of air and solvent. Alternatively, when the cleaning is performed only with the solvent, it is preferable that the cleaning is performed only with the air.

The colored paint a thus taken out of the system by extrusion and washing is recovered in the recovery tank (15) without being mixed with other colored paints, and is recovered by the CCV.
It can be reused by putting it in the paint tank (1) for the colored paint a communicating with (5).

After the extrusion and washing of the color paint a remaining in the path from the CCV (5) to the spray coater (7) as described above are completed, another color paint, for example, a color paint b From CCV (5) spray coating machine (paint gun)
It is possible to spray-coat the object to be coated by pressure feeding to (7).
After the coating of the colored paint b is completed, the colored paint b remaining in the path from the CCV (5) to the spray coater (7) is extruded and washed in the same manner as described above, and discharged and collected. The method is achieved by reducing the colored paint b to the paint tank (1) and reusing it.

When the other colored paints c, d, e,... Are further applied, the present method can be achieved by applying, extruding, washing, collecting, and reusing in the same manner as described above.

Examples of the colored paint include a solid color paint, a metallic paint, a light interference paint, a clear paint and the like. These are preferably liquid paints, and the viscosity at the time of painting is 13 to 40 seconds / Ford cup # 4. / 20 ° C., and the amount of application to the substrate is preferably in the range of 10 to 100 g / m ² .

The colored paint discharged from the passage is collected
It is preferable to carry out each of the coloring paints so that they do not mix with each other. Specifically, for example, in performing color change painting using three types of colored paints a, b, and c, dedicated collection tanks for each of these colored paints a, b, and c are prepared, and each tank is colored. It is preferable to collect the paint, and when the paint has accumulated to some extent, it is returned to the paint tank and reused. As a method of collecting the colored paints a, b, and c in the collection tank, for example, these collection tanks are placed on a moving table and the branch road (14)
It is preferable to set in advance so that the base automatically moves so that the colored paint that has passed through the dump valve (16) and the recovery tank for storing the same will coincide with the recovery tank, thereby simplifying the recovery operation.

[0023]

According to the present invention, when a plurality of colored paints are applied by the same spray coating machine, the amount of each colored paint and a cleaning solvent (thinner) is reduced, the environmental compatibility is improved, and the cost is reduced. It is now possible.

[Brief description of the drawings]

FIG. 1 is a system diagram of an embodiment of the present method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Colored paint tank 2 Solvent tank 3 Paint feed section 5 CCV (color change valve) 6 Route of hoses and pipes 7 Spray coater 13 Air feed section 14 Branch path 15 Recovery tank 16 Dump valve

Claims (1)

[Claims] 1. When two or more kinds of colored paints having different colors are successively changed by a spray coater having a color change valve, after the colored paints of each paint color have been applied, the valve is applied to the inside of the tip of the coating machine. The remaining colored paint is extruded with air and / or a solvent, then the inside is washed with a solvent and / or air, and the extruded paint and the washing liquid are collected for each colored paint of each coating color. A color change coating method characterized by being reused.