JPH0818342B2 - Molding and plating method for fiber reinforced resin molded products - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of molding and plating a fiber reinforced resin molded product such as an FRP molded product.

[0002]

2. Description of the Related Art Plating of thermoplastic ABS resin molded products is
Usually, as shown in FIG. 9, it is performed after a chemical etching process is performed in a pretreatment process of plating. However, among the thermoplastic resins, polycarbonate, polymer alloy (modified PPE / PA) and the like are difficult to plate, and therefore, the resin material is blended with a rubber material which is easily etched in advance, or As shown in FIG. 10, a special etching treatment process is added during the pretreatment process for plating. However, in a resin molding material that is difficult to plate, since the special etching treatment agent varies depending on the resin component, the process is complicated and a separate line is currently provided in the mass production line.

A sheet molding compound (hereinafter referred to as SMC), which is a typical molded product of FRP (glass fiber reinforced thermosetting resin) which has recently been put into practical use as an outer panel of an automobile, is compressed. Since the molded product obtained by molding uses unsaturated polyester resin as the matrix resin, it is difficult to plate, and fine holes called pinholes are generated on the surface of the SMC molded product. Even if the plating is applied, the appearance becomes poor, and it has been difficult to put the SMC molded product surface to practical use.

The in-mold coating method (hereinafter referred to as I
MC). This IMC is a method of painting simultaneously with molding of plastic. The present applicant has previously filed a patent application (Japanese Patent Application No. 1-81047, Japanese Unexamined Patent Application Publication No. 2-258) for the invention of the plastic inmold coating method.
No. 319). As shown in FIG. 6, when forming the work W with the split molds 6 and 7, the lower mold 6 is provided with the tab molding portion 3, and the upper mold 7 is provided with the paint injection hole 8 and the vacuum. An exhaust hole 9 connected to the pump is provided, the SMC material is set in the lower mold 6, and the SMC material is cured by maintaining a predetermined pressure for a predetermined time, and the air in the mold is vacuum deaerated from the exhaust hole 9. Then, the paint is injected from the injection hole 8 at a high pressure to the surface of the SMC.
It forms an MC coating film. FIG. 7 shows the work W of the front panel taken out of the mold.
Is still attached.

FIG. 5 is a perspective view of the work W, which is shown in FIGS.
FIG. 6 is a cross-sectional view taken along the line AA and the line BB of FIG. 5, respectively. As shown in FIG. 4A, the burr 1c appears on the edge of the work W of the work W taken out of the mold. Therefore, as shown by the broken line 4, the burr is cut to finish the work edge. do. Further, as shown in FIG. 4B, the tab 3 is also cut at the portion indicated by the broken line 4. The surface of the finished work is plated.
FIG. 8 shows a partial cross section of the product after plating.

The conventional FRP product plating methods are roughly classified into the following two methods. Similar to the above-mentioned conventional method, the surface of the FRP is pretreated with a chemical for etching and then plated. The FPR surface is previously spray-painted with a coating material that is easily etched in the normal plating pretreatment step, and then flowed in the normal plating step shown in FIG.

[0007]

As described above, it is necessary to cut the edge of the FRP molded product molded by the mold before plating. FIG. 3 shows the edge of the FRP molded product that has been cut and finished. The burr cutting portion 1a shown in FIG.
In the cut portion 1b of the tab shown in FIG. 3B, the surface of the cut portion is rough and the reinforcing fibers such as glass fibers are exposed, and these portions are in a state of easily absorbing moisture. Therefore, if the molded product as it is is flown to the plating process, the processing liquid may be absorbed into the molded product from the roughened portion of the surface, and this impregnated processing liquid may exude in the subsequent process.
In particular, a molded article soaked with the etching liquid is in a state where the etching liquid permeates into the sensitivity-imparting liquid in the subsequent sensitivity-imparting process and plating is not applied at all.

The present invention solves the above problems, prevents the occurrence of obstacles in the plating process of FRP molded products, etc., and allows the plating layer to adhere to the surface of the molded product with sufficient strength. It is an object of the present invention to provide a method of molding and plating.

[0009]

DISCLOSURE OF THE INVENTION According to the present invention, a reinforcing fiber mat formed by using a fiber having a normal length is arranged in the central portion of a molding portion of a molding die, and the reinforcing fiber mat is formed around the end edge portion thereof. A fiber-reinforced resin molded product obtained by arranging and molding a reinforcing fiber mat formed by using a fiber having a length shorter than that of the reinforcing fiber mat, finishing cutting the molded product, and then performing a plating treatment in a normal plating process. Molding and plating method.

[0010]

[Function] The center part of the molded product is a normal length of reinforcing fiber F
Since the RP is molded, sufficient strength is obtained, and the reinforcing fibers are exposed on the peripheral surface of the fiber-reinforced resin molded product that has been cut and finished after molding, but the exposed reinforcing fibers are short. Since it is a fiber, there is less exposure of the fiber at the cut part,
Infiltration of the treatment liquid is reduced in the chemical etching process of the plating process, and plating defects can be prevented.

[0011]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 2 shows the state of charge of the SMC material into the conventional molding die. In the center of the molding part of the lower mold 6, a normal class A SMC sheet material (1 inch glass fiber, glass fiber content 28 (~ 30%) 1A is charged, SMC is molded by the molding process as described above with reference to FIG. 6, and an IMC coating film is formed on the surface thereof. FIG. 1 shows a method of charging an SMC material according to the present invention. As in the conventional case, a conventional class A SMC sheet material 1A is provided at the center of the molding portion of the lower mold 6.
Is charged, and the outer periphery thereof is charged with an elongated shape short fiber class A SMC sheet material (glass fiber of 1/2 inch or less, glass fiber content rate 28 to 30%) 1B, and the end of the SMC sheet material 1A is charged. FRP that covers the edges and performs IMC in this state to form a coating film on the surface
Mold the molded product.

When this molded product is cut and finished, the burr cutting portion 1a shown in FIG. 3A and the tab cutting portion 1b shown in FIG. 3B.
Then, the surface of the cut portion is roughened and the reinforcing glass fiber is exposed. However, since the glass fiber of these portions is formed of the short fibers 1B, the glass fiber is less exposed, and this molded product is subjected to the plating process. When the molded product is dipped in various treatment liquids, the permeation of the treatment liquid is suppressed to a greater extent than the conventional one.
Since the majority of the molded product including the central portion is reinforced with the long fibers 1A, the strength of the molded product can be maintained.

[0013]

EFFECTS OF THE INVENTION According to the present invention, since the reinforcing fibers of short fibers are arranged around the molded product in advance, the exposed portion of the reinforcing fiber at the cut portion of the molded product after the finish cutting is reduced, and plating is performed. The absorption of the treatment liquid is reduced in the chemical etching process of the process, there is no possibility of mixing with the treatment liquid in the subsequent plating process, and the plating layer adheres to the surface of the molded product with sufficient strength.
Moreover, since the reinforcing fibers are short fibers only in the peripheral portion of the molded product, the strength of the molded product can be maintained.

[Brief description of drawings]

FIG. 1 is a plan view showing a method of charging an SMC material according to the present invention.

FIG. 2 is a plan view showing a conventional SMC material charging method.

FIG. 3 is a partially enlarged cross-sectional view of a molded product that is finished and cut after molding.

FIG. 4 is a partially enlarged cross-sectional view of a molded product after molding.

FIG. 5 is a perspective view of a molded product after molding.

FIG. 6 is a sectional view of a molding die.

FIG. 7 is a plan view of a molded product after molding.

FIG. 8 is a cross-sectional view of a molded product after plating.

FIG. 9 is a diagram of a normal plating process.

FIG. 10 is a plating process diagram including a special process.

[Explanation of symbols]

1 SMC molded product 1A Normal class A
SMC sheet material 1B Short fiber class A SMC sheet material 2 IMC coating 3 Tab 4 Cutting line 5 Plating layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Soho Hasegawa 8 Tsutana, Fujisawa City, Kanagawa Prefecture Isuzu Central Research Institute Co., Ltd. (72) Inventor Ryobo Narasaki 8th Shelf, Fujisawa, Kanagawa Isuzu Co., Ltd. Central Research Institute (72) Inventor Takashi Fujita 8 Isuzu Central Research Institute, Fujisawa City, Kanagawa Prefecture Isuzu Central Research Institute (72) Inventor Ryomitsu Suyama 8 Tsuchitan, Fujisawa City, Kanagawa Isuzu Central Research Institute (72) ) Inventor Tokiko Ohori 8 Tsutana, Fujisawa City, Kanagawa Prefecture, Isuzu Central Research Institute

Claims (1)

[Claims] 1. A reinforcing fiber mat formed by using fibers having a normal length is arranged in the center of a molding portion of a molding die, and a length shorter than that of the reinforcing fiber mat is provided around an edge of the reinforcing fiber mat. Molding by arranging and molding a reinforcing fiber mat formed by using a sliver fiber, and after finishing cutting the molded product, molding of a fiber reinforced resin molded product characterized by performing a plating treatment in a normal plating step, Plating method.