JPH0260938A - Laminated structure and its production - Google Patents

Abstract

PURPOSE:To obtain the title structure composed of fibrous cloths which are partially fixed in relative positions with a fused resin by laminated fibrous cloths impregnated with a resin mixture of a thermoplastic resin with a thermosetting resin and partially heating the assemblage to fuse said resin. CONSTITUTION:A plurality of fibrous cloths (e.g., woven fabric of nylon 6) impregnated with a synthetic resin mixture of a thermoplastic resin (e.g., polyvinyl butyral resin) with a thermosetting resin (e.g., phenol resin) and partially heating the assemblage to, for example, a temperature from the softening point of the thermoplastic resin to the curing temperature of the thermosetting resin by, desirably, ultrasonic heating to fuse the synthetic resin.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a laminated structure for providing various molded products with uniform thickness and uniformity, especially compression molded products. The present invention relates to a method for manufacturing a laminated fSm body which stably provides such a laminated structure.

(Prior art) Conventionally, a sheet material made of synthetic fiber cloth impregnated or coated with a thermosetting resin (hereinafter referred to as prepreg) is cut into a specific planar shape, and multiple pieces are assembled in a predetermined phase to be three-dimensionally formed. However, the reality is that the uniformity of such molded products depends on the skill level of the molding operator at the time of assembly.

(Problems to be Solved by the Invention) Normally, when fabric laminates are molded, especially compression molded, prepregs are preliminarily assembled (hereinafter referred to as preform) with each layer having a certain phase. This preform product is charged into a mold or clamped and heat-molded. However, during this charging or mold clamping, the mutual position (phase) between the fabrics of each layer shifts, making it impossible to obtain a uniform laminate. It is difficult to fit such complex shapes into molding, and improvements are urgently needed.

The present invention provides a laminated structure that can provide a uniform molded product without phase shift even in a preform with a three-dimensional molding amount such as a three-dimensional curved body. The present invention provides a method for stably and efficiently producing a body.

(Means for Solving the Problems) The present invention adopts the following means to solve the problems. That is, (1) in a laminate consisting of fiber fabrics containing a synthetic resin mixture of a thermoplastic resin and a thermosetting resin, the partially fused synthetic resin controls the relative position of the fiber fabrics; A laminated M4 structure characterized by being fixed.

(2) A laminated structure characterized by laminating a plurality of fiber fabrics impregnated with a synthetic resin mixture of a thermoplastic resin and a thermosetting resin, and then partially heat-treated to fuse the synthetic resin. How the body is manufactured.

(3) The method for manufacturing a laminated structure according to claim (1), wherein the heat treatment is performed using ultrasonic waves.

Examples of wjM applicable to the present invention include fibers made of polymers such as nylon, polyester, polyurethane, polyacrylonitrile, polypropylene, vinylon, aromatic polyamide, high-strength polyethylene, high-strength polyvinyl alcohol, and high-strength acrylonitrile, and fluorine fibers; Carbon I! , glass W4 fiber, metal fiber, etc.

As the fabric made of such fibers, for example, sheet-like materials such as woven fabrics, knitted fabrics, and nonwoven fabrics can be used.

In the present invention, a mixture of two types of synthetic resins, a thermoplastic resin and a thermosetting resin, is used in terms of fusion properties and shape stability.

The thermoplastic resin of the present invention has the function of fusing adjacent layers and positioning (phase) the fabrics, and not only has plasticity and adhesive properties, but also has a thermosetting component when heated. It may also react to form a copolymer. Examples of such thermoplastic resins include polyamide resins, polyester resins, polyurethane resins, methacrylic resins, and polyvinyl butyral resins.

Examples of thermosetting resins include unsaturated polyester resins, crosslinkable polyurethane resins, epoxy resins, phenol resins, vinyl ester resins, urea resins, melamine resins, and polyimide resins.

At least one type of such thermoplastic resin and thermosetting resin is selected from each resin group and mixed. A particularly preferred combination of mixed resin compositions is polyvinyl butyral resin and phenol resin, and this mixed resin composition has excellent prepreg processability and fusion properties.

The mixing ratio of thermoplastic resin/thermosetting resin is selected depending on the characteristics of the applied resin and the intended use of the molded product, but is preferably 20/80 to 70/30, more preferably 40/80.
A range of /60 to 60/40 is adopted. When the thermoplastic resin content is less than 20%, the fusion properties tend to decrease, and the
% or more, moldability tends to deteriorate.

The weight ratio of synthetic fiber/synthetic resin is determined depending on the intended use of the molded article, and is preferably selected from the range of 5/95 to 501501, and more preferably 10/90 to 40/60.

The prepreg sheet of the present invention is formed by a method such as an in-shell solution impregnation method or a coating method.

The flip-preg of the present invention is characterized in that the synthetic resin between the layers is partially fused, and the fused area and range are determined by the shape of the cut prepreg product, the shape of the preform product, etc. Usually less than 5 percent of the surface area is sufficient.

As such a welding method, a method capable of heating a small area can be preferably employed, and in particular, the use of an ultrasonic welder is selected from the viewpoint of work efficiency.

The fusion conditions are selected to be above the softening temperature of the thermoplastic resin and below the curing temperature of the thermosetting resin, or for a time within a range where curing does not proceed, but the key is to ensure that the fabric layer does not peel off during molding. It is sufficient if they are fused.

The laminate product assembled in this manner is a preform product in which the phase of each layer is accurately fixed.

Next, the present invention will be explained in more detail with reference to Examples.

(Example) Example 1 Nylon 6Bili fiber 1200 denier was used, weaving density;
19 x 19 pieces/inS trade: 226 g/m plain weave with polyvinyl butyral/phenol resin (mixing ratio 501
The prepreg (Fig. 1) soaked with 50"IJ-530" (manufactured by Road Far East Co., Ltd.) to a coating weight of 56 g/Ko was cut into 6 multi-petal shapes with a diameter of 50 cm.
A marked line was marked at the center of each valve, and a fusion point was marked on the marked line 20 mm inside from the end of the valve, on the circumference with a radius of 120 mm from the center, and at the center of the multi-valved valve (No. Figure 2). 24 sheets of this prepreg were prepared.

To assemble a hemispherical shape with a diameter of 30 cm, place the first prepreg (dotted line) in a hemispherical shape in the container, and shift the phase of the second prepreg (solid line) by 15 degrees with respect to the first prepreg. Using a hand-type ultrasonic welder, the fusion point of the prepreg was irradiated to such an extent that the two layers were lightly fused, and a circular surface with a diameter of 1 Q mm was fused (Fig. 3). The next sheet was laminated on top of this laminate and fused in the same way.This operation was repeated to assemble 24 sheets of prepreg to obtain a hemispherical preform product. The phase was accurately fixed, and no phase disturbance occurred even with a small amount of external force.

This preform product was transferred to a hemispherical mold with a diameter of 25 cm, and molded at 160° C./100 tOn for 30 minutes to obtain 1 q of hemispherical molded products.

1 on the circumference 80mm above the lower edge of this molded product
I drilled two through holes with a drill. Next, the 20 layers were mechanically peeled off one by one from the inside, and the actual number of laminated layers at the positions of the through holes was counted.

The results are shown in Table 1.

Comparative Example 1 Using the same prepreg as in Example 1, a preform product was produced by assembling the layers without adhesion. This was molded under the same conditions as in Example 1 to obtain a hemispherical molded product.

12 on the circumference 80mm above the lower edge of this molded product.
I drilled through holes in places. Next, 20 sheets were mechanically peeled off one by one from the inside, and the actual number of laminated sheets to be punched at the position of the through hole was counted.

The results are shown in Tables 1J3 and 2.

Table 1 Table 2 As is clear from the above coating, Example 1 had a uniform lamination state at all locations, whereas Comparative Example 1 had misalignment between layers and was rarely laminated unevenly. .

Comparative Example 2 In Example 1, only polyvinylbutyral resin was used as the resin without mixing the phenol resin, and the rest was carried out in the same manner as in Example 1 to produce a preform product, which was then molded into a mold. Loaded and molded.

It was found that this molded product had some blisters and had extremely poor releasability when released from the mold, making it difficult to obtain a normal molded product.

(Effect of the invention) The present invention provides a molded product made by plying a plurality of sheets of prepreg,
In particular, for molded products with complex shapes such as three-dimensional curved objects, the laminated fabric can be positioned easily and stably, and it also exhibits the characteristics that no phase shift occurs during molding. Therefore, it can be effectively applied to molding various laminates.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an example of a resin-impregnated multi-valve fabric for a laminated structure of the present invention, Fig. 2 is an example of a cut prepreg sheet with fusing points marked, and Fig. 3 is a preform product. This is an example. In the figure: 1: Synthetic fiber fabric 2: Synthetic resin 3 Nibbly preg sheet 4: Fusion point 5: Cutting prepreg sheet 6: First sheet 7: Second sheet 8: Fusion part 9 Nibbly formed product

Claims (3)

[Claims] (1) In a laminate made of fiber fabric containing a synthetic resin mixture of a thermoplastic resin and a thermosetting resin, the partially fused synthetic resin fixes the relative position of the fiber fabric. A laminated structure characterized by: (2) A laminated structure characterized by laminating a plurality of fiber fabrics impregnated with a synthetic resin mixture of a thermoplastic resin and a thermosetting resin, and then partially heat-treated to fuse the synthetic resin. How the body is manufactured. (3) The method for manufacturing a laminated structure according to claim (1), wherein the heat treatment is performed using ultrasonic waves.