JPS5818219B2 - Manufacturing method for FRP molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing FRP molded products, and more specifically
This invention relates to a method for producing an FRP molded product that is easy to handle during FRP molding by using a fibrous material coated with a specific synthetic resin as a base material for P molding.

BACKGROUND ART Conventionally, injection methods, cold press methods, band lay-up methods, etc. have been used as molding methods for forming an FRP layer on the surface of an FRP molded product or a laminated material to obtain a molded product having a laminated structure.

However, these molding methods require reinforcing materials such as glass fibers or laminated materials and glass fibers to be inserted into the mold, but it is difficult to insert them smoothly into the mold due to fraying, fuzzing, and elasticity of the fibers. In particular, there is a problem when adhering fibers to the laminated material, which requires a great deal of labor and time, and it is difficult to obtain a homogeneous molded product.

The present invention solves the above-mentioned drawbacks and provides a method for manufacturing an FRp molded product, which allows easy insertion of a base material for FRP molding, greatly improves productivity, and enables manufacturing of high-quality FRP products. The purpose is to

・In other words, the present invention is a method for manufacturing an FRP molded product by inserting an FRP molding base material into a mold and then adding a thermosetting liquid resin, in which a material consisting only of fibrous materials or A laminated material having at least a part of the surface made of a fibrous material, in which part or all of the surface of the fibrous material is coated with a film-like or tape-like synthetic resin that can be dissolved in a thermosetting liquid resin is used. The present invention provides a method for manufacturing an FRP molded product characterized by the following.

The material for the FRP molding substrate used in the present invention may be made of only fibrous material, but it is generally preferable to use a laminate of fibrous material and other materials.

Note that in this laminated material, if there is no fibrous material on the surface, there is no need to cover it with a synthetic resin, so the laminated material used in the present invention has at least a part of the surface formed of a fibrous material. This is the case.

The above fibrous materials are not particularly limited, and include glass fibers such as chopped strand mats, continuous strand mats, and cloth; inorganic fibers such as asbestos; vegetable fibers such as cotton and hemp; animal fibers such as wool; and rayon. Regenerated fibers such as;
Various materials such as synthetic fibers such as nylon, vinylon, and polypropylene, as well as metal fibers can be used.

On the other hand, other materials other than the fibrous material of the laminated material include foamed plastics such as foamed polyethylene and foamed polyurethane; inorganic lightweight materials such as ALC1 foamed clay, calcium silicate, and perlite mortar; paper honeycomb, plastic honeycomb, cement board; A wide variety of materials such as wood and metal can be used.

Further, the shape of these materials may be arbitrary, such as block, rod, hollow, plate, etc., and may be appropriately determined depending on the shape of the FRP molded product to be manufactured.

Furthermore, in the laminated material, the fiber layer can be laminated on any surface, such as the entire surface, both surfaces, or one surface of the material.

Next, the surface of the fibrous material of the above material is coated with a synthetic resin.

This coating is carried out to prevent the fibrous material from fraying, fuzzing, etc. Therefore, it is most effective to cover the entire surface of the fibrous material, but it may also be partially coated in the form of a band.

Furthermore, the synthetic resin may be in the form of a film to cover the fibrous material, or may be wrapped in the form of a tape.

Here, the synthetic resin material is assumed to be soluble in the thermosetting liquid resin.

This is because in the present invention, when manufacturing FRP by putting the FRP molding base material into a mold and pouring a thermosetting resin into it, if the synthetic resin covering the fibrous material does not dissolve. This is because the liquid resin does not penetrate into the fibrous material, and as a result, the base material and the thermosetting resin are not integrally bonded, resulting in an FRP with insufficient strength.

This thermosetting liquid. Examples of synthetic resins that can be dissolved in the resin include polystyrene, which is usually used for unsaturated polyester resins.

The base material for FRP molding used in the present invention may be coated with a synthetic resin on the surface of the fibrous material as described above, but the synthetic resin on the surface of the base material may be melted or heat-shrinked instead of as it is. .

If the synthetic resin is melted or heat-shrinked in this way, the fibrous material will also shrink, fraying, fuzzing, etc. will be almost completely eliminated, and the shape will be fixed, making handling convenient.

Examples of the shape of this FRP molding base material include those shown in FIGS. 1 to 4.

In the method of the present invention, the above FRP molding base material is inserted into a mold, and then a thermosetting resin such as unsaturated polyester is inserted and injection molding, press molding, band lay-up molding, etc. are performed to produce an FRP molded product. can be manufactured.

According to the method of the present invention, the fraying, fuzzing, elasticity, etc. of the fibers of the FRP molding base material are suppressed, so it is easy to insert the FRP molding base material into the mold, and the process of FRP molding is simplified. It can be made continuous and mechanized, and it is possible to improve the working environment and yield.

In addition, wear and tear on the mold used for molding is prevented, resulting in a longer service life.

Furthermore, the FRP thus obtained has improved quality, is stable and uniform, and can be effectively used in a wide range of fields such as general industrial parts, building materials, and general industrial materials.

Next, examples of the present invention will be shown.

Example 1 Glass fiber mat (chopped strand mat 450
f? /crrl) 350imX 350tttm
After stacking three sheets, the top and bottom were sandwiched between biaxially stretched polystyrene films (thickness: 20 μm), and the ends were hot-melt bonded to obtain a base material for FRP molding.

Next, this base material is inserted into a press mold, and then unsaturated polyester resin (ortho type, viscosity 3 poise, curing time 3
0 minutes), press molding is performed, and the thickness of the unsaturated polyester resin is 28511! An FRP molded plate was obtained.

In this case, the mat was easier to handle and the molding cycle was improved compared to when no polystyrene film was used.

In addition, the bending strength of the obtained molded product was 23 kg/mJ, the bending elastic modulus was 870 kg/m4, and the tensile strength was 9 kg/mJ.
, the tensile modulus of elasticity was 700 ky/-, which was no different from the case where no polystyrene film was used.

The test method was JIS K-6911.

Example 2 Polyurethane resin foam (88 mm x 88 mm x 20
00mm, density 0.03 S'/Cfn3) with glass fiber mat (continuous pine t-1soofI/
After wrapping i) and further wrapping a biaxially oriented polystyrene film (thickness 20μ), the ends were sealed with hot melt welder and left in an oven at 150°C for about 1 minute to shrink and form glass fiber into the core material. A base material for FRP molding was obtained by bringing the materials into close contact with each other.

Next, this base material is inserted into a closed mold, and an unsaturated polyester resin (ortho-based, viscosity 3 poise, curing time 30 minutes) is applied at a pressure of 3 to 4 kg/ca through a nozzle provided in a part of the mold. After injecting and curing, remove from the mold, 90im
A prismatic molded product of 2000 mm was obtained (FRP thickness 1 m).
m).

In this case, compared to the case where polystyrene film was not used, the time for inserting the base material into the closed mold was halved, and the molding cycle was significantly improved.

In addition, the obtained molded product has a bending strength of 133 kg/lri
:, bending rigidity was 300×10' kg-crA.

The test method is JIS A 1414゜6.9 span distance 1800m! ? I did it with +1.

[Brief explanation of drawings]

Figures 1 to 3 are cross-sectional views showing each aspect of the FRP molding base material used in the method of the present invention, and Figure 4 is a cross-sectional view showing one embodiment of the FRP molding base material used in the method of the present invention. FIG. In the figure, 1 is a synthetic resin membrane, 2 is a fibrous material, 3 is another material, and 4
indicates a void.

Claims (1)

[Claims] 1. In a method of manufacturing an FRP molded product by inserting an FRP molding base material into a mold and then adding a thermosetting liquid resin, a material consisting only of fibrous material as the FRP molding base material Alternatively, use a laminated material at least a portion of which is made of a fibrous material, in which part or all of the surface of the fibrous material is coated with a synthetic resin in the form of a film or tape that is soluble in a thermosetting liquid resin. A method for producing an FRP molded product, characterized by: 2. A method for manufacturing an FRP molded article according to claim 1, which comprises melting or heat-shrinking the coated synthetic resin. 3. The method for producing an FRP molded article according to claim 1, wherein the synthetic resin soluble in the thermosetting liquid resin is polystyrene. 4. Claims No. 4 in which the material other than the fibrous material of the laminated material, at least a part of whose surface is made of fibrous material, is foamed plastic, inorganic lightweight material, paper...nicomb, plastic honeycomb, cement, wood, or metal. A method for manufacturing an FRP molded product according to item 1.