JPH02277619A - Reinforced plastic product - Google Patents

Abstract

PURPOSE:To obtain an FRP product having impact resistance and beautiful appearance at a low cost by forming a matrix of thermosetting resin incorporating the specified amount of an inorganic flake and providing a flake lining layer made of this matrix between a gel coating layer and an FRP layer. CONSTITUTION:A flake lining material is formed by incorporating 10 - 50wt.% preferably 20 - 40wt.% inorganic flake into thermosetting resin. A gel coating layer is provided by utilizing this flake lining material having 0.2 - 2.0mm thickness as an intermediate layer. As the thermosetting resin, single substance or the mixture of unsaturated polyester resin, epoxy resin, vinyl ester resin and urethane resin is utilized. Further as the inorganic flake, the material such as glass, mica, carbon, metal and metallic oxide is utilized and discoid or platelike solid is suitable which has 1 - 50mum thickness and 100 - 5,000mum diameter (or length). A fibrous filler having <=10mm length such as glass, saturated polyester, carbon, aramid and vinylon besides the inorganic flake may be incorporated at <=30wt.% into this intermediate layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reinforced plastic (hereinafter abbreviated as FRP) product having a gel coat layer.

[Conventional technology]

FRP products that have a gel coat layer generally consist of a gel coat layer and a reinforcing layer (an intermediate layer may be provided between the gel coat layer and the reinforcing layer if necessary) from the surface of the product.

Usually, the gel coat layer has a high resin content and has a thickness of 0.3~
It is a non-FRP JiJ with a length of about 0.7 m, and is colored to give a beautiful appearance to the product.

The reinforcing layer is FRPJi and is responsible for the structural strength of the product.

In this case, the pattern of the FRPN reinforcing material (so-called glass tab) stands out on the gel coat, resulting in a very unfavorable result from the aesthetic point of view of the product.

[Problem to be solved by the invention]

As mentioned above, since the gel coat layer is thin, the pattern of the reinforcing material of the FRP layer stands out. This is said to be due to curing shrinkage of the resin used as the matrix.

As one of the countermeasures, there is a method of molding FRP using a matrix with a small shrinkage rate, but this method has problems in terms of strength and cost. Another method is to make the gel coat layer thicker, but this poses problems with respect to mechanical or thermal shock.

As a result of intensive research into a solution to the above problems, the present inventors have found that inorganic flakes such as glass, mica, carbon, metal, metal oxide, etc. are added between the gel coat layer and the FRP layer (that is, as an intermediate layer) 10-50-t%, preferably 2
By providing a flake lining layer with a thermosetting resin matrix such as unsaturated polyester resin, epoxy resin, vinyl ester resin, or urethane resin containing 0 to 40-t%, it is possible to achieve impact resistance at low cost. We have discovered that it is possible to obtain an FRP product with an aesthetically superior appearance, and have arrived at the present invention.

[Means to solve the problem]

In the present invention, 10 to 5 inorganic flakes are added to the thermosetting resin.
The present invention relates to a reinforced plastic product having a gel coat JW containing 0 wt %, preferably 20 to 40 wt %, and having a thickness of 0.2 to 2.0 mm, using a flake lining material as an intermediate layer.

The thermosetting resin in the present invention includes unsaturated polyester resins, epoxy resins, vinyl ester resins, urethane resins alone or in mixtures.

Here, the unsaturated polyester resin includes, for example, αβ unsaturated dibasic acids such as maleic acid, maleic anhydride, and fumaric acid, and if necessary, dibasic acids such as phthalic acid, isophthalic acid, and adipic acid, and ethylene glycol. Glycols such as propylene glycol and neopentyl glycol,
A suitable mixture is a diluted mixture of about 20 to 50 L% of a vinyl compound such as styrene or vinyltoluene to a condensation reaction product esterified by a conventional method.

The epoxy resin is an epoxy compound having two or more epoxy groups in the molecule, and examples thereof include Epicoat 828.1004 manufactured by Yuka Shell Co., Ltd.

The epoxy resin may contain, as a curing agent, an amine compound having two or more amine groups in one molecule, or a polybasic acid anhydride, if necessary.

Vinyl ester resin is produced by adding 1.0 to 0.9 mol of an unsaturated basic acid such as acrylic acid or methacrylic acid to 51 mol of epoxy in the above-mentioned epoxy resin using a conventional method. , and a vinyl compound such as styrene, vinyl, toluene, etc., diluted and mixed at about 20 to 50% by weight.

Urethane resin is a compound containing two or more NCO5 molecules in one molecule, such as I-lylene diisocyanate, hexamethylene diisocyanate, etc., and a polyester polyol having an OH group at the end and having a number average molecular weight of 500 to 10,000. Compounds obtained by reaction are suitable.

Inorganic flakes include glass, mica, carbon,
Made of metal, metal oxide, etc., with a thickness of 1 to 50 microns and a diameter (or major axis) of 100 to 5000 microns.
A disk-shaped or plate-shaped solid having .

In addition to inorganic flakes, this intermediate layer may also contain 30 wt% or less of a fibrous filler having a length of 10+a+a or less, such as glass, saturated polyester, carbon, aramid, or vinylon.

Additionally, 50-L% of colorants and fillers, such as powders of calcium carbonate, hydrated alumina, silica, talc, clay, etc.
May include the following:

〔Example〕

EXAMPLES Hereinafter, in order to explain the present invention more specifically, Examples and Comparative Examples will be given and explained, but the present invention is not limited to these Examples.

Glass plate with smooth surface (500 x 450 x 5 mm)
is prepared, subjected to mold release treatment using a wax-based mold release agent in a conventional manner, and placed on a mold.

Gel coat resin (
Apply isophthalic acid-based unsaturated polyester resin base) to a thickness of about 0.4 mm and dry to the touch. Further, an intermediate layer and a reinforcing layer were formed on this gel coat surface under the conditions shown in Table 1 to obtain FRP test pieces of comparative examples and examples of the present invention.

Table 2 shows the surface smoothness as an indicator of the aesthetic appearance of the gel coat surface using the Suga Test Instruments Co., Ltd. photo-1 image sharpness measuring device (N
SIC type) and JIS K5
400 method impact test results (the drop height (minimum) in which the crank hits the gel coat surface when an impact is applied from the gel coat surface is expressed in cm).

By using a flake lining material in the intermediate layer of an FRP product having a gel coat layer, the present invention makes it possible to obtain an FRP product with excellent impact resistance and surface smoothness, and the effect of industrial use is extremely high.

〔Effect of the invention〕

The reinforced plastic manufacturing of the present invention has the following advantages compared to conventional ones:
It is clear from Table 2 that the impact resistance and surface smoothness are excellent.

Patent applicant: Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. A reinforced plastic product having a gel coat layer and a flake lining layer with a thickness of 0.2 to 2.0 mm containing 10 to 50 wt% of inorganic flakes in the intermediate layer.