JPH10328062A - FRP molded body - Google Patents

Abstract

(57) [Summary] [PROBLEMS] There is no fear of losing the heat retaining effect due to secondary foaming or thermal deformation at a high temperature, good adhesion to a reinforcing fiber reinforced resin layer, and local reinforcement of a desired portion is possible. FR reinforced with a reinforced fiber reinforced foam layer formed by a mechanical foaming method, which has a foaming magnification of a desired portion and which can be arbitrarily adjusted.
A P-shaped body is provided. SOLUTION: The surface is a gel coat layer 21, the second layer is a reinforced fiber reinforced resin layer 22, and a reinforced fiber reinforced foam layer 31 formed by a mechanical foaming method is laminated on the resin layer. FRP molded article 1 characterized by the following.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an FRP molded article reinforced by a foamed layer formed by a mechanical foaming method.

[0002]

2. Description of the Related Art As a method of manufacturing a bathtub or the like made of FRP,
A gel coat resin is applied to the mold to a certain thickness, a reinforcing fiber reinforced resin layer is formed thereon and cured, and in some cases, a plywood or a hard plastic foam plate is sandwiched and cured, and then further cured. A method is generally known in which a foaming undiluted solution of polyurethane is sprayed on and foamed to form a heat insulating layer.

[0003] However, the heat insulating layer composed of a polyurethane foam layer sometimes undergoes secondary foaming due to the moisture in the bath tub and deforms the bath tub. In some cases, the insulation effect as a heat insulating layer may be lost. In addition, the second layer of the reinforced fiber reinforced resin layer (FRP)
Layer) and polyurethane are different materials, so that the adhesion is not always sufficient and peeling may occur. Further, depending on the shape of the bathtub, there is a case where there is a portion to be reinforced locally, but a reinforcing effect cannot be expected with a polyurethane foam. In the method of sandwiching and reinforcing plywood or the like, there is a problem in that man-hours are required to locally laminate the plywood or the like in a sandwich shape.

In order to solve this problem, there has been proposed a method in which a chemically foamed unsaturated polyester resin layer containing short glass fibers is used in place of the polyurethane foam layer as the heat insulating layer (Japanese Patent Publication No. Sho. No. 60-33504).

[0005]

In the above-mentioned method in which the chemically foamed unsaturated polyester resin layer containing short glass fibers is used as a heat insulating layer, the unsaturated polyester resin in which the foam resin is fiber-reinforced is used. Therefore, there is no concern about loss of the heat retaining effect due to secondary foaming or thermal deformation at a high temperature, the reliability of adhesion to the FRP layer is improved, and local reinforcement of a desired portion can be performed. However, since it is a chemical foaming method using a thermal decomposition type foaming agent, it is difficult to obtain a uniform foam in a shaped article such as a bathtub in which it is difficult to heat each part to the same temperature. It is difficult to form a layer having a uniform thickness. In addition, since the expansion ratio mainly depends on the amount of the expansion control agent to be mixed with the unsaturated polyester resin, it is impossible to change the expansion ratio only at a specific portion.

The present invention has been made in consideration of the above circumstances, and has as its object to eliminate the possibility of the heat insulating layer being secondary foamed or losing the heat retaining effect due to thermal deformation at a high temperature. An object of the present invention is to provide an FRP molded article reinforced by a reinforcing fiber reinforced foam layer having good adhesiveness, capable of locally reinforcing a desired portion, and capable of arbitrarily adjusting the expansion ratio of a desired portion. .

[0007]

Means for Solving the Problems The present inventor has proposed the above FRP.
As a result of repeated studies to improve the problems of the molded body, the present inventors have found that the above problems can be improved by using a reinforcing fiber-reinforced unsaturated polyester resin foam layer formed by a mechanical foaming method, and completed the present invention. did.

That is, in the FRP molded article of the present invention, the surface is a gel coat layer, the second layer is a reinforced fiber reinforced resin layer, and the reinforced fiber reinforced foam layer formed by a mechanical foaming method is formed on the resin layer. It is characterized by being laminated.

In the present invention, the resin used for the gel coat layer, the reinforcing fiber reinforced resin layer and the foam layer is FR.
It is a resin generally used in the field of P molded articles, and examples thereof include unsaturated polyester resins, vinyl ester resins, and diallyl phthalate resins. When the use of the FRP molded article requires heat resistance such as a bathtub, a bisphenol-based or isophthalic acid-based unsaturated polyester resin or a vinyl ester resin is preferably used for the gel coat layer and the reinforcing fiber reinforced resin layer.

The above-mentioned gel coat layer is usually formed by applying a mixed solution obtained by mixing a resin, a curing agent and, if necessary, a pigment onto a mold using a spray gun. The thickness of the gel coat layer is usually 0.1 to 1.0 mm.

Examples of the reinforcing fibers used in the reinforcing fiber reinforcing resin layer and the foam layer include inorganic fibers such as glass fibers and carbon fibers, and organic fibers such as aramid fibers and polyester fibers. Glass fibers are preferred in terms of price.

When the content of the reinforcing fibers in the reinforcing fiber reinforcing resin layer is less than 5% by weight, the effect of reinforcing the resin is insufficient, and furthermore, the curing shrinkage of the resin cannot be suppressed, and the surface of the product such as sink marks is not formed. Appearance defects are likely to occur, and if it exceeds 40% by weight, molding work becomes difficult. Therefore, 5 to 40% by weight is appropriate, and 10 to 30% by weight is preferable.

The reinforcing fiber reinforced resin layer is laminated on the gel coat layer by a spray-up method using a conventionally known spray-up machine or a hand lay-up method. In the case of the spray-up method, short fibers having a length of 2 to 60 mm are used as reinforcing fibers. In the case of the hand lay-up method, roving or cloth is used in addition to the short fibers. The thickness of the formed reinforcing fiber reinforced resin layer is usually 0.5 to 2 mm.

As a method of forming a foamed layer formed by the mechanical foaming method, first, a stock solution obtained by adding a curing agent, a curing accelerator, a foam stabilizer and the like to the above resin, and a mixture of nitrogen gas and carbon dioxide gas are used. The compressed inert gas is guided to a compressed gas mixing device, mixed well, and the gas is finely dispersed to be contained in the stock solution to form a creamy foam.
Next, the compressed gas mixing device is connected to a conventionally known spray gun with a chopper, and the foamed stock solution and the cut reinforcing fibers are sprayed on the reinforcing fiber reinforcing resin layer to form a layer, and the layer is cured. To form. In this case, the cutting length of the reinforcing fibers is suitably 6 to 12 mm, and the content of the reinforcing fibers with respect to the resin is 10 to 10 mm.
15% by weight is suitable, and preferably 12 to 15% by weight.

In this forming method, the expansion ratio is adjusted according to the type of compressed gas used and the gas pressure. Depending on the type and amount of the reinforcing fibers used, the desired heat insulating properties, the desired reinforcing properties, etc., the specific gravity of the foam layer is usually
0.14 to 1.2. The thickness of the foamed layer is usually up to about 15 mm, although it depends on the specific gravity of the foamed layer.

[0016]

The FRP molded article of the present invention has a gel coat layer on the surface, a reinforced fiber reinforced resin layer (FRP layer) on the second layer, and a reinforced fiber reinforced foam formed on the resin layer by a mechanical foaming method. Since the layers are laminated, the foamed layer is free from the fear of losing the heat retaining effect due to secondary foaming and thermal deformation at high temperatures.
The FRP molded article has good adhesion to the layer, can locally reinforce a desired portion, and can arbitrarily adjust the expansion ratio of the desired portion.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of the embodiment of the FRP molded body of the present invention. As shown in FIG. 1, the main body 2 of the FRP molded body 1 (the bathtub in this embodiment) is
In part A, the gel coat layer 21 on the surface is a layer made of bisphenol-based unsaturated polyester resin colored by adding a pigment and having a thickness of 0.2 mm, and a second layer of a reinforcing fiber reinforced resin layer (FRP layer). 22 is a layer of bisphenol-based unsaturated polyester resin having a thickness of 1.0 mm in which 30% by weight of glass short fibers having a length of 25 mm are mixed,
The FRP layer is made of an orthophthalic acid-based unsaturated polyester resin foam layer 31 formed by a mechanical foaming method and having a thickness of 9 mm in which short glass fibers having a length of 10 mm are mixed by 12% by weight.
(Specific gravity: 0.7) and is reinforced.

Part B has a thickness of the foam layer 31 of 13 mm.
The thickness of the foamed layer 31 is the same as that of the portion A because the portion 32 is a corner portion and requires strength because the portion 32 is thicker than the portion A. The structure has a layer 33 with a specific gravity of 1.0 by reducing the magnification.

The above-mentioned foamed layers 31, 32 and 33 are made of orthophthalic acid-based unsaturated polyester resin (manufactured by Showa Polymer Co., Ltd., Rigolac FM-08).
B), a curing agent, a curing accelerator, and a foam stabilizer are added thereto to obtain a stock solution, and this stock solution and compressed nitrogen gas (gas pressure of 350) are used.
0 kPa) into a compressed gas mixing device and mixed well with stirring to form the stock solution into a creamy foam containing finely dispersed nitrogen gas, and a spray gun with a chopper connected to the compressed gas mixing device. Then, the foamed stock solution and the cut short fibers were sprayed onto the FRP layer 22 to form them.

The foam layers 31, 32, and 33 can be controlled by the hand switch of the compressed gas mixing device to change the expansion ratio by adjusting the amount of nitrogen gas introduced, and by the hand switch of the spray gun. Since the amount of the resin to be sprayed and the length and the amount of the glass fiber can be adjusted, the thickness of the foam layer and the expansion ratio can be easily changed as in the above foam layers 31, 32, and 33.

[0021]

The structure of the FRP molded article of the present invention is as described above, and the foamed layer does not have a fear of secondary foaming or loss of the heat retaining effect due to thermal deformation at high temperature, and has good adhesion to the FRP layer. Thus, it is possible to provide a FRP molded body that can locally reinforce a desired portion and that can arbitrarily adjust the expansion ratio of the desired portion.

[0022]

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one example of an FRP molded body of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 FRP molded object 2 Main body 21 Gel coat layer 22 FRP layer 31, 32, 33 Foam layer

Claims (1)

[Claims] The surface is a gel coat layer, the second layer is a reinforced fiber reinforced resin layer, and a reinforced fiber reinforced foam layer formed by a mechanical foaming method is laminated on the resin layer. FRP molded body