JPS5968218A - Manufacture of two-tone color bumper cover - Google Patents

Abstract

PURPOSE:To simplify substantially the processing steps, by peeling off coating films on the tops of partitions for enclosing a prescribed sector, closing the mold, injecting a polyurethane raw material into the mold, and removing the molded item after a prescribed period has passed. CONSTITUTION:The coating film on the sector (a) that will be enclosed by the partitions 11 wherein the coating films 14 on the tops of the partitions 11 ground off is peeled off. In this case, as the coating films on the tops of the partitions 11 have been removed, the coating films of the sectors (a, b, c) are not continuous, and if the coating film on the sector (a) is pulled, the coating films on the adjacent sectors (b, c) are not affected, and only the coating film on the sector (a) can be peeled off. The mold is closed by the top force 16, and a polyurethane raw material 17a is injected. The position of the injection of the polyurethane raw material may be determined by the flow of the raw material or the like. After a prescribed period has passed, the molded item is removed, and the burr is removed to obtain a two-tone color bumper cover.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a two-tone bumper cover.

For the purpose of protecting the vehicle body in the event of a collision and preventing damage to the bumper, a bumper is used in which an energy absorber made of polyurethane foam is covered with a bumper cover made of polyurethane. From a fashionable point of view, those painted in Tsurutonkawa came to be used.

However, conventional manufacturing methods require many steps. FIG. 1 is a diagram showing the manufacturing process of a conventional two-to-y Kawono pumper cover. This manufacturing method will be explained according to the symbols in the drawings.

(a) A polyurethane raw material is injected from the injection port into a closed molding mold having a cavity of a predetermined shape and coated with a mold release agent, and a bumper cover is molded using the RIM molding method (reaction injection molding method). do.

(b) Remove from the mold after a predetermined period of time has elapsed.

(c) Paris processing.

2) Clean the bumper cover surface with solvent to remove oil such as mold release agent.

(g) Heating and curing in a furnace to volatilize the solvent.

(f) Masking for color separation is done using tape or the like.

(g) Primer treatment is applied to make the surface uniform and to improve adhesion with colored paint.

To complete the reaction of the primer and dry it, it is heated and cured in an oven.

(S) Paint M color.

E) This is a process that is performed only when clear coating is applied to preserve the colored coating and add gloss.

0) To complete the reaction of the paint and dry it, heat it in a furnace and cure it.

(a) Remove the tape used for masking.

If the two-tone color is the background color of the bumper cover, such as black, the above process is sufficient, but if both colors are painted, the process becomes more complicated.

As described above, conventional manufacturing methods require a large number of steps, and improvements are required.

The present invention provides a rational method for manufacturing a two-tone cup bumper cover that eliminates the above-mentioned problems.

Hereinafter, the present invention will be described in detail using the accompanying drawings.

FIG. 2 shows the lower mold of the mold used for carrying out the present invention.
FIG. 6, a partially cutaway perspective view of the sales example, is a cross-sectional view taken along section line II in FIG. 2.

A partition 11 is erected on the inner surface of the lower mold 10, and the partition 11 divides the inner surface of the lower mold into a plurality of sections, in this embodiment, three sections, a, 't), and C.

The top of the partition has a shape that makes it easy to scrape off the paint film, which will be described later, such as an R shape with a small radius or a partially pointed shape, and the height d and thickness θ of the partition are selected as appropriate depending on the shape of the bumper. be done.

FIG. 4 is a manufacturing process diagram of an embodiment of the manufacturing method of the present invention.

The following description will be made according to the symbols shown in this figure.

(a) After applying the # molding agent to the inner surface of the lower mold 10 described in FIGS. 2 and 6, a clear paint 12a is applied.

(b) Clear 1 formed by applying clear paint
A colored paint 13a is applied onto the No. 11 film 12b.

Generally, clear paint and colored paint are collectively called paint. This paint is preferably polyurethane-based. Moreover, the clear paint is used when the colored paint is metallic. Therefore, if the colored paint is not metallic, the application of the clear paint is omitted.

(c) Place the low tool 15 on the top of the partition 11 to rub the coating film formed on the top of the partition 11.

Due to the friction of this low two 15, the partition 11 of the coating film 14 formed by applying the clear paint and the colored paint
The top part of is scraped off.

b) Peel off the paint film in section a surrounded by the partition 11 from which the top paint film 14 has been removed.

At this time, partition! Since the coating film was removed at the top of section 711, the coating films of sections (@a, b, and c are not continuous, and even if the coating film of section a is removed, the sections pHib and gν of section pHib,
It is possible to remove the paint film only in section 1iIi7a without affecting the paint film c.

b) The mold for molding is closed with the upper mold 16, and polyurethane raw material l7at is injected. Polyurethane raw material J (is considered to be a compound for R-M molding.

Note that the injection position of the polyurethane raw material is determined by the flow of the raw material, etc., and is not limited to the position shown in FIG.

(f) After a predetermined period of time, the mold is removed and paris is removed.

Get a two-tone bumper cover. 17 shows a polyurethane having a predetermined shape formed by reaction curing of polyurethane raw materials.

Fig. 5 shows the manufacturing process shown in Fig. 4 by process name, and the conventional 11! ! This corresponds to the manufacturing process diagram in Figure 1 for the manufacturing method.

By comparing these two figures, it can be seen that the manufacturing method of the present invention is significantly simpler than the conventional manufacturing method. In other words, the cleaning steps shown in Figure 1,
This eliminates the need for a curing step and (g) a brimer treatment step.

The reason why such drastic simplification was possible is described below.

First, in the past, a cleaning process was required because after the bumper cover was molded in a mold, in order to paint the surface, it was necessary to remove oils and fats such as L711 molding agent from the bumper cover surface. However, in the present invention, since there is no mold release agent interposed between the coating film and the polyurethane, this cleaning step is not necessary, and the curing step of solvent volatilization is also not required. Become.

In addition, in the past, since the bumper cover molded in the mold was painted in a post-process, the paint film adapted to the surface condition of the bumper cover and had a nine-surface coating. It was necessary to fill in the unevenness of the pinholes on the surface of the cover and make it smooth. Furthermore, in the past, adhesion between the paint film and the bumper cover was achieved only by the adhesive properties of the paint, resulting in insufficient peel strength. From these points, a primer treatment was required to smooth the surface of the bumper cover and improve the adhesion between the paint film and the bumper cover.

However, in the present invention, since the coating film is formed on the smooth inner surface of the lower mold, the coating film surface becomes smooth, and the adhesion between the coating film and polyurethane is reduced during the reaction of the polyurethane raw materials. The adhesion is strong due to the pressure of the polyurethane raw material injected with a little over/<-back, so no brimer treatment is required.

Historically, since the coating film is cured by the reaction heat of the polyurethane raw material, a single curing step is not necessary.

On the contrary, friction of the paint film on the top of the partition and peeling off of the compartment paint film are required, which were not required in the past, but this replaces the conventional masking and masking removal and requires a substantial increase in the number of steps. It won't be.

The manufacturing process shown in FIGS. 4 and 5 is an example of manufacturing a two-tone bumper cover in which the base color of the bumper cover, for example, black, and the paint film are painted in a - color. To manufacture a two-tone bumper cover made of colored paint, the manufacturing process shown in FIG. 6 is used.

In order to manufacture a two-tone bumper cover using two-color coating, as shown in Figure 6, after the separation process of the compartment coating film in (i), the clear coating in (e) and the different color in (f) are applied. It is necessary to apply the colored coating to the area where the paint film has been removed, making it complicated by Q, but even in the past, when using two colored coatings, it was necessary to apply the colored coating twice in different colors. , compared to the past, there is no contact and separation, and as with the case of one-color painting, the cleaning process, primer treatment process, and curing process that were required in the past are no longer necessary, and the overall effect is , which has been greatly simplified.

FIG. 7 is a perspective view of a two-tone bumper cover manufactured according to the present invention using the molds shown in FIGS. 2 and 6; The color of the bumper cover is the base color of the bumper cover, such as black, or the color of the paint film formed within the palindromic area of the partition, both of which are different from the color of the paint film in 2. .

FIG. 8 shows the bottom ff of the mold used for carrying out the present invention.
l A partially cutaway perspective view of the embodiment 112, and FIG.
It is formed by forming.

FIG. 10 shows the perspective opening of a two-tone cuff-bumper cover manufactured according to the present invention using the mold shown in FIGS. 8 and 9. Section of IU lower mold 20] 1, k
is molded with one part of the lower mold, and j and k are painted in black.

The method for manufacturing the two-tone bumper of the present invention includes:
The coating film formed in the section surrounded by the partition set up in the lower mold of πM for molding is peeled off, or after the coating film is peeled off, a coating film of a different color is formed in this section, and then the mold for molding is removed. A two-tone cowl bumper cover is produced by injecting polyurethane raw materials into the mold and integrating the paint film inside the mold, eliminating the cleaning process and Bufimer treatment that were previously required.
It is a very rational method as it eliminates the need for a single curing process.

[Brief explanation of the drawing]

Fig. 1 is a manufacturing process diagram of a conventional two-tone cup bumper cover, Figs. 2 to 10 are diagrams explaining the present invention, and Fig. 2 is a partially cutaway perspective view of the lower side of a molding die. , FIG. 6 is a sectional view taken along cutting line 1-- of FIG. 2,
Figures 4 and 5 are manufacturing process diagrams using one color coating, Figure 6 are manufacturing process diagrams using two color coatings, ff17 Figures i and J: Perspective views of two-tone bumper power par embodiments. , Fig. 8 and Fig. 9 show hanging molds and other embodiments, Fig. 8 is a partially cutaway perspective view, Fig. 9 is a plan view, and Fig. 10 is a perspective view of two-tone cuff-bumper cover and other embodiments. It is a diagram. 10.20... Lower mold of mold, 11.21... Partition, 12a... Clear paint, 12b... Clear coating film, 15a... Colored paint, 14... Paint film, 15
...Roller, 16... Upper mold of the mold, 17a.
...Polyurethane raw material, 17...Polyurethane, a,
b, c, h, i...Division, α...Elegance of partition, e...Thickness of partition Patent applicant: Inoue MBC Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4 (A)
(d)10
10 Figure 5 (a) Figure 6 111 (f) Figure 7 Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] 1. (A paint film is formed by applying paint to the inner surface of the lower mold of a mold that is divided into a plurality of sections by a partition installed on the inner surface of the mold. fr:I) Desired The coating film on the top of the partition surrounding area N is squeezed with a loaf or the like. → Peel off the paint film in the area surrounded by the partition. 2) After closing the mold, the polyurethane raw material is injected into the mold. Q: Remove the mold after a predetermined period of time. It consists of the above steps. How to make two-tone bumper covers. 2. (a) Paint is applied to the inner surface of the lower mold of the mold, which is divided into a plurality of sections by partitions erected on the inner surface, to form a coating film. Trunk) Rub the paint film on the top of the 7J stem surrounding the desired section with a roller or the like. e9 Part I; y Peel off the coating in the area surrounded by part I. b) Apply a paint of a color equal to the above paint to the area to form a paint film. (After the mold is closed, the polyurethane raw material is injected into the mold. (f) The mold is removed after a predetermined period of time has passed. A method for manufacturing a two-tone cupper, which consists of the above steps.