JPH05185023A - Multicolor coating method - Google Patents

Abstract

PURPOSE:To easily draw a parting line after coating at the time of coating a material in multiple colors by forming a first-color coating film on the material and then forming a second-color coating film while masking the material on the region shifted from the parting line to ward the first-color coating film. CONSTITUTION:When a material 1 such as an automobile body is multicolor- coated, an electrodeposition coating film is firstly formed on the material 1, an intermediate coating film is formed, as required, and a first-color coating film 2 is formed thereon. A masking material 5 is fixed along the predetermined parting line 4 by using a double coated adhesive tape on the ends. A second- color coating film 6 is formed on the masking material 5 beyond the parting line 4. The masking material 5 is removed, the part of the second-color coating film 6 on the first-color coating film 2 beyond the parting line 4 is irradiated with a laser beam emitted from a laser oscillator and removed, and a two-tone coating is obtained with the colors separated by the parting line 4.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a multicolor coating method.
More specifically, it relates to a method of removing an extra second color coating film on the surface of the first color coating film, for example, when the object to be coated is multicolored.

[0002]

2. Description of the Related Art In painting an automobile body or the like, so-called two-tone painting in which the body is divided into two or more colors is used as one means for improving the appearance.

When the object to be coated is divided into multiple colors, a method of forming a first color coating film, covering the coating film, and then forming a second color coating film has been conventionally used. This conventional method will be described with reference to the drawings.

6 to 8 are explanatory views showing a conventional multicolor coating method in the order of steps.

As shown in FIG.
The color coating film 12 is formed, and then the parting line 14 is positioned. As a method of positioning the parting line (hereinafter referred to as a parting method), for example, an applicator film having the same size as a predetermined dimension from a geometrically target line (hereinafter referred to as a character line) in the object to be coated to the parting line. Alternatively, using a positioning film or a jig such as a synthetic resin mold product, a marking can be made at some point on the parting line with a felt pen, and the marking is connected with a parting tape 13 to obtain the parting line 14. It is common. Next, a masking material 15 for covering the first color coating film is attached onto the parting tape 13 using a double-sided adhesive tape.

Next, as shown in FIG. 7, the second color coating film 16
To form. The second color coating film 16 covers even a part of the masking material 15.

Finally, as shown in FIG. 8, the parting tape 13 and the masking material 15 are removed. Thus, the two-tone coating can be obtained with the upper end of the parting tape 13, that is, the parting line 14 as a boundary.

In addition to the narrow parting tape, a parting tape integrated with a masking material is used, but when the parting line is curved or the distance between both ends of the coating film is long. Has the drawback that the parting line is distorted due to slack of the tape, even if the integrated one is used. Furthermore, depending on the position of the character line,
If the jig becomes large, it will be difficult to close off,
There is a drawback that the coating cost increases.

Moreover, in any conventional method, when the masking material and the parting tape are peeled off after the coating and drying of the second color coating film in any case, the second color coating film on the masking material peels off in the form of strips. As a result, there is a problem in that it adheres to the first color coating film to cause coating bleeding, or even a necessary portion of the second color coating film is peeled off together with the parting tape.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems in the conventional parting method, and an object thereof is to provide a method for performing two-tone painting without accurately positioning the parting line. And

[0011]

According to the present invention, after a first color coating film is formed on an object to be coated, masking is performed by shifting the first color coating film side from a predetermined parting line to the second color coating film side, and then the second coating film is formed. A multi-color coating characterized by forming a color coating film and removing the masking, and then irradiating a laser beam to remove a portion of the second color coating film existing on the first color coating film beyond the parting line. Regarding the painting method.

[0012]

According to the multicolor coating method of the present invention, the masking of the first color coating film is not accurately applied to the parting line using the parting tape as in the conventional case when the second color coating is applied. Provided with a slight deviation on the color coating surface side, after the second color coating, the extra second color coating film on the first color coating surface is irradiated with a laser beam to decompose, carbonize, volatilize, evaporate, etc. It is removed by the method described above, and it is possible to make a break more easily than the conventional method.

[0013]

The multicolor coating method of the present invention will be described below with reference to the drawings.

1 to 4 are explanatory views showing an embodiment of the method of the present invention in the order of steps.

As shown in FIG.
The color coating film 2 is formed. When the article 1 to be coated is an automobile body or the like, an electrodeposition coating film, and if necessary, an intermediate coating film is formed on the article 1 to be coated, and the first color coating film 2 is formed thereon. .. After that, the masking material 5 is almost along the parting line 4.
Are attached to the ends using double-sided adhesive tape. The parting line can be determined by a conventional method that has been used conventionally, but by irradiating the laser beam from the laser oscillator with a small output (for example, Ne-He laser) to the position of the parting line and utilizing the light spot, A masking material may be attached. In the method of the present invention, the masking material 5 is the second
Exactly the parting line 4 if it does not cover the area of the color coating
The position of the parting line does not need to be as accurate as the conventional method at this stage because it is not necessary to follow the method, and the operation is easier than the conventional method. Alternatively, a parting tape may be attached in advance along the parting line 4, and the masking material 5 may be attached to the parting tape using a double-sided adhesive tape. In this case, the parting tape does not need to be accurately aligned with the parting line 4.

The deviation of the edge of the masking material from the parting line is preferably narrow as long as the work is not difficult, and is usually in the range of about 5 to 15 mm.

Next, as shown in FIG. 2, the second color coating film 6
To form. The second color coating film 6 extends over the parting line 4 and even over the masking material 5. FIG. 3 is a view showing a state after the masking material 5 has been peeled off, and the second color coating film 6 crosses the parting line 4 and is left over the unmasked portion on the first color coating film 2. It exists as the second color coating film 7. By irradiating the extra second color coating film 7 with a laser beam emitted from a laser oscillator to remove the laser beam, two-tone painting in which the parting line 4 is color-coded as shown in FIG. 4 is obtained. In FIG. 3, 9 is an optical fiber for guiding a laser beam.

FIG. 5 shows an additional second color coating film 7 with a laser beam.
It is explanatory drawing at the time of removing. In FIG. 5, the tip of the laser beam emitted from the laser oscillator 8 is a supporting device.
First by an optical fiber 9 held by 10
The second color coating film portion 7 to be removed on the color coating film 2 is guided and irradiated, and sequentially moved to remove the coating film. In FIG. 5, the article to be coated 1 and the supporting device 10 are separated from each other for ease of illustration, but in reality, the two are located close to each other,
The tip of the optical fiber 9 supported by the supporting device 10 is arranged to be close to the painted surface.

The supporting device 10 for supporting the tip of the optical fiber 9 preferably has five or more axes and a traveling function, and for example, a robot with a traveling axis is used. The tip of the optical fiber 9 is preferably supported so that the laser beam is always irradiated perpendicularly to the surface to be irradiated. In addition to the laser beam irradiation device, the support device 10 is provided with an identification device for identifying the first color coating film and the second color coating film and for confirming the range of the second color coating film to be removed. Is good. While confirming the second color coating film portion 7 to be removed by this identification device, the tip portion of the optical fiber 9 is reciprocated up and down to remove the second color coating film portion 7, and at the same time, the supporting device 10 is removed. The object to be coated 1 is moved in one direction (for example, the parting line direction) to remove the entire second color coating film portion 7 to be removed.

The laser beam is applied to the second color film on the first color coating film.
Only the color coating film is removed without damaging the first color coating film, and the wavelength, output, irradiation time, etc. are
And the type of the second color paint, the thickness of the second color coating film, and the like. When painting a car, YA with an output of 10 to 300 W
It is preferable to irradiate the G laser beam while moving at a speed of 0.2 to 5 mm / sec, usually about 1 mm / sec.

The irradiation spots can be widened by bundling a large number of the optical fibers, and it is preferable to change the number of the optical fibers to be used and change the area of the irradiation spots according to the situation.

Next, a specific example of the present invention will be described. A polybutadiene-based electrodeposition coating is electrodeposited on a 0.8 mm thick dull steel plate that has been subjected to zinc phosphate chemical conversion treatment, and baked at 170 ° C for 25 minutes to form an electrodeposition coating with a thickness of 20 μm. A black melamine-alkyd resin coating composition was applied on almost half of the coating composition to a thickness of 25 μm after drying and baked at 140 ° C. for 20 minutes to form a black first color coating film. Next, about 10 mm from the parting line
A masking material was applied so that it was shifted to the black coating film side. Next, apply red melamine-alkyd resin paint to the rest of the coating so that it slightly covers the masking material.
It was baked for 20 minutes to form a red second color coating film having a thickness of 30 μm, and then the masking material was peeled off to obtain a test piece.

Next, a laser beam from a YAG laser oscillator having an output of 100 W was guided by a quartz optical fiber (high power laser guide optical fiber made by Toshiba Corp.) and adhered to the black coating side from the parting line of the test piece. It was irradiated on the red coating film. The moving speed of the fiber tip was about 1 mm / sec. Thus, the excess red coating could be removed without damaging the black coating.

As described above, according to the method of the present invention, it is not necessary to perform the troublesome operation of accurately sticking the parting tape along the parting line, and the parting in multicolor coating can be easily performed with a reduced number of steps. be able to.

[0025]

According to the method of the present invention, it is possible to easily perform a parting off of a multicolor coating film without using a parting tape to determine a parting line.

Further, the parting line is sharply determined by removing the coating film with the laser beam, and the parting line can be adjusted even after the second color coating, so that the parting defect is reduced and the cost is reduced.

[Brief description of drawings]

1 shows an embodiment of the method of the invention,
It is explanatory drawing which shows the state which attached the masking material on the 1st color coating film.

FIG. 2 shows an embodiment of the method of the invention,
It is explanatory drawing which shows the state which formed the 2nd color coating film.

FIG. 3 shows an embodiment of the method of the present invention,
It is explanatory drawing which shows the state which removed the masking material.

FIG. 4 shows an embodiment of the method of the invention,
It is explanatory drawing which shows the state which removed the 2nd color coating film which exceeded the parting line with a laser beam.

FIG. 5 shows an embodiment of the method of the present invention,
It is explanatory drawing at the time of removing an excessive coating film with a laser beam after completion | finish of 2nd color coating.

FIG. 6 is an explanatory view showing a conventional method and showing a state in which a parting tape and a masking material are attached to the first color coating film.

FIG. 7 is an explanatory view showing a conventional method and showing a state in which a second color coating film is formed.

FIG. 8 is an explanatory view showing a conventional method and showing a state in which a parting tape and a masking material are removed.

[Explanation of symbols]

 1 coating object 2 first color coating film 4 parting line 5 masking material 6 second color coating film 7 extra second color coating film portion 9 optical fiber

Claims (1)

[Claims] 1. After forming a first color coating film on an object to be coated,
Masking is performed by shifting to the first color coating film side from a predetermined parting line, then forming a second color coating film, and after removing the masking, existing on the first color coating film beyond the parting line. A multicolor coating method, which comprises irradiating a laser beam to remove a portion of the second color coating film.