JPH057222Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is applicable to FRP molding, especially fiber presetting.
It relates to the fiber base material used in the RIM molding method.

(Prior art) Conventionally, in the fiber preset RIM molding method,
The textile material 10 set in the mold is produced by press-molding the fiber base material using upper and lower molds 8, or by applying chopped strand fibers 12 to the mold surface 11, as shown in FIG. 3A and B. The preformed fiber base material 10 is set in a mating mold 13 as shown in FIG. 3D, and resin is injected through the resin injection hole 14. , molded by solidification.

In this case, the fiber base material used may be cross mat (Fig. 4 A), chopped strand mat (Fig. 4 B), continuous strand mat (Fig. 5 C), or a combination thereof. It is structured accordingly.

However, the above-mentioned fiber base material is only shaped as a whole by the sum of the frictional force between the fibers or the weak bonding force due to the adhesive, and external forces concentrate at the ends of the base material or FRP molding Therefore, even simply moving the substrate often causes the fibers to become frayed. The frayed fibers 15 are FRP
They penetrate into the product after molding (Fig. 5), resulting in not only poor appearance but also deterioration of physical properties.

As a means to prevent fraying and misalignment of the fibers at the ends of the fiber cloth used as a fiber base material for FRP molding, it has been proposed to cover the ends of the fiber cloth with adhesive tape. −48795 Publication,
(Japanese Patent Application Laid-open No. 183467/1983).

However, using such fiber substrates
When RIM molding is performed, when resin is injected into the fiber base material set in the mold, the resin does not penetrate sufficiently into the edges of the fiber cloth covered with adhesive tape, resulting in a good molded product. The disadvantage is that it cannot be obtained.

(Problem to be solved by the invention) The present invention is a fiber base material for FRP molding that does not cause fraying or shedding of fibers at the ends of the base material or deformation of the entire base material, and has good resin impregnation properties even at the ends. The challenge is to provide the following.

(Means for Solving the Problems) The fiber base material for FRP molding of the present invention consists of one or more layers of fiber base material having a shape that conforms to the product shape, and the peripheral portion of the fiber base material is treated with adhesive, It is also characterized in that it is fixed with tape provided with a plurality of holes or notches.

In the present invention, various fiber base materials are used, such as cross mats, chopped strand mats, continuous strand mats, or combinations of fibers such as glass fibers, carbon fibers, and synthetic fibers. The fiber base material preferably has 1
It is composed of one or more fiber cloths. When the fiber base material is made of a single sheet of fiber cloth, after the fiber cloth is shaped in advance to fit the shape of the product, at least one of the front and back surfaces of the fiber cloth corresponding to the edges of the product is treated with adhesive on one side. A tape is placed around the fibrous base material and the fibers at the periphery of the fiber base material are fixed with the tape. In addition, when forming a fiber base material by laminating multiple sheets of fiber cloth, one sheet of fiber cloth is placed along the mold surface having the shape of the product, and both sides of the fiber cloth are placed around the edges of the product. Adhesive tape is applied, then another fiber cloth is placed on top of it, and the fiber cloths are joined together by compression.
It is preferable to construct a fiber base material by repeating this operation and laminating a required number of fiber cloths.

(Function) In the present invention, the adhesive tape placed around the entire periphery of the edges between the fiber base materials fixes the fibers at the ends of the fiber base materials and prevents the fibers from fraying, coming off, or forming the base material at the ends of the base materials. Prevents deformation of the entire material.

In addition, since the adhesive tape has multiple holes or cuts, when the fiber base material is set in the mold and the resin is injected, the resin may also enter the fiber base material through the holes or cuts. This improves the impregnation of the resin at the ends of the fiber base material.

(Example) The present invention will be explained in detail by the following examples.

FIG. 1A is a perspective view of the fiber base material of the present invention; B is an enlarged view of part A. C shows an enlarged view of 6 in B.

In FIG. 1, numeral 1 indicates a fiber base material preformed into the shape of a product, and the fiber base material is constructed by laminating four layers of glass fiber crossmat 3 in which warp threads 4 and weft threads 5 are alternately woven. A plurality of semicircular notches 7 are made around the edge, and a width of 10 mm from the periphery is made so that the adhesive tape 6, which has been adhesive-treated on both sides, is sandwiched between the glass fiber chroma mats 3. They are placed around the entire circumference.

FIG. 2 is an explanatory diagram showing the manufacturing process of the fiber base material 1. First, the glass fiber cross mat 3 is molded into a shape that conforms to the product shape using the upper and lower molds 8 (Fig. 2 A), and a plurality of circular holes 7 with a width of about 20 mm are formed around the entire circumference of the part corresponding to the product end periphery 2. The provided adhesive tape 6, both surfaces of which are treated with adhesive, is pasted so that the center in the width direction of the tape 6 corresponds to the end portion 2 (FIG. 2D) (FIG. 2B).
A glass fiber cross mat is laminated on top of it and compressed (Fig. 2 D), and then the same operation is repeated twice to laminate four layers of glass fiber cross mat,
Under compression, cut around the edge of the product (second
A fiber base material shown in Figure 1 was obtained.

(Effects of the invention) In the present invention, although adhesive tape with multiple holes or cuts is used to fix the fibers at the end of the fiber base material, the holes or cuts are The effect of fixing the fibers at the ends of the fiber base material was shown to be the same as when using a non-stick adhesive tape. That is, the adhesive tape placed around the ends of the fiber base material fixes the fibers at the ends of the fiber base material to each other, and prevents the threads at the ends, which conventionally tend to fray, from fraying. No more loose threads get mixed into the product. In addition, even when a large number of fiber base materials are laminated, the adhesive tape firmly joins the fiber base materials, improving the bonding force, eliminating fiber misalignment, waviness, sagging, etc., and eliminating fiber orientation. It no longer reduces the strength of the Furthermore, the bonding force of the adhesive tape prevents the fiber base material from turning over, and therefore, bent fiber base materials are no longer seen in the product.
Physical properties no longer deteriorated.

Since the fibers at the ends are no longer frayed, there is no longer any frayed fibers mixed into the burrs of the molded product, reducing the number of trimming steps.

In addition, since the adhesive tape has multiple holes or notches, when resin is injected during the RIM molding process, the resin may enter the base material through the holes or notches even at the edges of the base material. Compared to the case where a tape without holes or notches is used, even the edges of the base material are sufficiently impregnated with resin, resulting in a good molded product.

[Brief explanation of the drawing]

Figure 1 A is a perspective view of the fiber base material of the present invention, B is an enlarged view of part A thereof, C is an enlarged view of B, and Figure 2 shows the manufacturing process of the fiber base material of the present invention. Explanatory diagram, Figure 3 shows the conventional fiber preset
An explanatory diagram of the RIM molding method, Figure 4 shows the fiber base materials used, A is a cross mat, B is a chopped strand mat, C is a continuous strand mat, and Figure 5 is a conventional This is a diagram of a product manufactured using the RIM molding method. In the figure, 1... fiber base material, 2... fiber base material end,
3...Glass fiber cross mat, 4...Warp, 5
... Weft thread, 6 ... Adhesive tape, 7 ... Semicircular cut, 8 ... Upper and lower mold, 9 ... Circular hole, 10 ...
... Fiber base material, 11 ... Mold, 12 ... Chopped strand fiber, 13 ... Layered mold, 14 ... Resin injection hole, 15 ... Frayed fiber.

Claims (1)

[Claims for Utility Model Registration] (1) Consisting of one or more layers of fiber base material that conforms to the shape of the product, the periphery of the fiber base material is treated with adhesive, and a plurality of holes or notches are provided. characterized by being fixed with tape
Fiber base material for FRP molding. (2) The FRP according to claim 1 of the utility model registration, in which the fiber base material is made of a single layer, and at least one of the front and back surfaces of the peripheral portion of the base material is fixed with a tape treated with adhesive on one side. Fiber base material for molding. (3) The fiber for FRP molding according to claim 1, wherein the fiber base material is composed of multiple layers, and the base materials are fixed to each other in the peripheral portions with a tape that is adhesive-treated on both sides. Base material.