JPS61212363A - Partial painting method for automobile bumper - Google Patents

Abstract

PURPOSE:To obtain an excellent finish without the exudation of paint by sticking a masking sheet having an adhesive part on the unpainted part side of a parting line, coating a strippable paint, then cutting with a laser beam and painting. CONSTITUTION:In the local painting method of a plastic automobile bumper integrally molded with the skirt part, the grille part, etc., the bumper part 2 is covered with a masking sheet 8 of vinyl chloride resin, etc., having an adhesive part 9, when the adhesive part 11 at the peripheral edge of the sheet 10 is adhered at a position in the grille part 4 on the slightly inner side of a parting line l2 between the skirt part 3 and the grille part 4. Then a strippable paint is coated on the parting line in specified width by a roller brush, etc., and dried to form the coated film of the resin. The film is cut by melting with a laser beam along the parting line. Consequently, cutting is performed strictly along the parting line even on a curved surface and an excellent finish can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for partially painting a resin barber for an automobile in which a skirt portion, a grille portion, etc. are integrally molded.

(Prior Art) Recently, resin bumpers with integrated skirt portions, grill portions, etc. have been used as bumpers for automobiles.

For example, due to the relationship with the side moldings of the car body, the bumper part is black, the skirt part is the same color as the car body, and the grille has a complicated shape that is difficult to paint and is recessed from the car body surface. In some cases, the base color of the resin is black without being painted.

In this case, if the color of the resin itself is black, there is no need to paint the bumper part and the grille part, but the skirt part must be painted.

For this reason, the conventional method is to apply tape along the paint separation line, or to apply strippable paint to the surface of the resin molded product, as disclosed in Japanese Patent Application Laid-Open No. 57-35970. , this is dried to form a resin coating,
There is a known method in which the resin coating is then cut along the parting line using a cutting tool or the like, the resin coating is peeled off from the area to be painted, and then a paint is applied to the area to be painted.

(Problems to be Solved by the Invention) In the above-described method of applying the tape along the parting line, adhesion deteriorates on curved surfaces and it is difficult to adhere the tape in line with the parting line. In addition to poor workability, there is also the problem that the paint oozes between the tape and the non-painted surface, and when using strippable paint, it is necessary to apply strippable paint to the front of the non-painted part as well. This increases the material cost, and since cutting is performed using a cutting tool, it is not possible to cut along the parting line on curved parts, and when cutting with a cutting tool, there is a risk of cutting from strippable paint. This may drag the resin coating, causing paint to bleed in this area and damaging the surface of the resin product.

In particular, if the grille is integrally formed as a bumper and the strippable paint is applied to the inside of the grille, the subsequent peeling work becomes extremely troublesome.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a masking sheet having an adhesive portion at the edge, and the edge of the masking sheet is formed along the parting line and further than the parting line. Paste it on the side of the non-painted part to cover the non-painted part. Next, use a roller brush or the like to apply strippable paint on the parting line with a width that spans the edge of the masking sheet, and dry this strippable paint. The resin coating was cut along the parting line with a laser beam, the resin coating in the area to be painted was peeled off and painted, and then the resin coating and the masking sheet in the non-painted area were peeled off as one piece.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a perspective view of the front bumper before painting. This front bumper (1) is made of black resin, for example, and includes a part of the bumper (2), a skirt part (3), and a grill part (4).
) are integrally molded, and the bumper part (2) has a front lamp mounting hole ('5)', the skirt part (3) has an air hole (8), and the grill part (4) has a grid (7). has been established.

Fig. 2 also shows a masking sheet made of vinyl etc. prepared for painting, and the masking sheet (8) shown in Fig. 2 (A) covers a part of the bumper (2), and the -side edge of the masking sheet (8) shown in Fig. 2 (A) is the adhesive part (9) that has been pre-applied with adhesive.
The masking seam (10) shown in Fig. 2 (B) is slightly smaller in size than the grille part (4), and the adhesive part (11) is pre-applied with adhesive on its periphery.
is formed.

The procedure for partially painting the skirt portion (3) of the bumper (1) using the above masking sheets (8) and (10) will be explained based on FIGS. 3 to 8.

First, as shown in FIG. 3, a masking sheet (8) is used to cover a part of the bumper (2) that is not painted, and a masking sheet (10) is used to cover the grille (4). The adhesive part (9) on the edge of the bumper part (2) and the skirt part (3) 11AC
, Jl+) at a position slightly closer to the bumper part (2), and the adhesive part (
11) is glued at a position slightly inside the grille part (4) than the parting line (12) between the skirt part (3) and the grille part (4).

Next, as shown in FIG. 4, for example, black strippable paint (13) is applied to the parting lines (9, +) and (uz) in a predetermined width using a roller brush (12) or the like. The width of this strippable pane) (13) is the parting line (text θ,
The left and right sides should be approximately the same width based on C1x), and the ends of strippable panes (13) are masked (8) and adhesive parts (9) of (10).

(The width should be such that it overlaps the other side.

The applied strippable paint (13) is then dried to form a resin coating (14), and this resin coating (14)
As shown in FIG. 5, the laser beam (16) from the laser beam oscillator (15) fuses along the parting line (Q+). Here, as a laser beam.

YAG laser, CO2L/-za, Ar1z-za, HeN
An e-laser or HeCd laser is used.

Next, as shown in FIG. 6, the melted resin coating (14)
Of these, the part (14a) formed on the bumper part (2) and the grill part (4) is left, and the part (14b) formed on the skirt part (3) is peeled off.
) A paint (18) is applied to the surface using a spray gun (17) as shown in FIG.

After the paint (18) has dried, the masking sheets (8) and (io) are peeled off as shown in FIG. Then, since the resin coating (14a) formed on the bumper part (2) and the grille part (4) overlaps the edges of the masking sheets (8) and (10), this resin coating (14a) ) is also peeled off at the same time.

Furthermore, even if the resin coating (14a) is not completely peeled off and some of it remains, the resin coating (14a) and part of the bumper (2
) or the grill part (4) are the same black color, so they are not noticeable.

In the embodiment, a roller brush was used to apply the strippable paint in a predetermined width, but the invention is not limited to the roller brush, and any means such as a sponge brush may be used.

(Effects of the Invention) As explained above, according to the present invention, the strippable paint (resin coating) is melted using laser light, so there is no disadvantage of pulling the strippable paint when cutting, and the strippable paint can be cut by cutting. The paint does not ooze out between the paint and the surface of the non-painted area, and by cutting using a laser beam, curved parts can be cut in line with the parting line, resulting in a smooth finish. In addition, since the strippable paint to be applied only needs to be of a specified width, it is possible to save on strippable paint, and after A-mounting, the masking sheet and the strippable paint can be peeled off in one piece, which simplifies the work. It has many effects.

[Brief explanation of the drawing]

Figure 1 is a perspective view of the resin bumper before painting, Figure 2 (A
) and (B) are perspective views of the masking sheet, and FIGS. 3 to 8 are sectional views of the bumper sequentially explaining the partial painting process. In the drawings, (1) is an automobile bumper, (2) is a part of the bumper, (3) is a skirt part, (4) is a grill part, (8),
(10) is a masking sheet, (12) is a roller brush,
(13) is a strippable paint, (14) is a resin coating, (15) is a laser beam oscillator, (17) is a spray gun, and (18) is a paint. Patent applicant: Agent for Honda Motor Co., Ltd.
Patent Attorney Part 2 1) Part 1 Patent Attorney
Kuni Ohashi Production volume Patent attorney Small
Yama Yuyuki Patent Attorney No 1)
ShigeruFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8

Claims (1)

[Claims] Glue the edge of a masking sheet along the parting line to the non-painted part of the resin bumper separated by the painting parting line to cover the non-painted area, and then set the width where one end of the masking sheet covers the edge of the masking sheet on the parting line. After applying the strippable paint with the paint and drying the strippable paint to form a resin film, the resin film is irradiated with a laser beam along the cutting line to cut the resin film. A bumper for an automobile, characterized in that the resin film is peeled off from the part to be painted, then the part to be painted is painted, and then the masking sheet covering the non-painted part is peeled off together with the resin film adhering to the masking sheet. Partial painting method.