JPS63165124A - Manufacture of molded item - Google Patents

Abstract

PURPOSE:To make it possible to provide both aesthetic sense and water resistance by a structure wherein a mixture of radical-curing type resin and glass flakes as filler is set as an intermediate layer next to a gelcoat layer. CONSTITUTION:Flake compound is applied to a layer next to a gelcoat layer. Further, a layer with the necessary thickness is laminated to the flake compound layer by using glass fibers and radical-curing type resin. As the radical-curing type resin, unsaturated polyester resin, vinylester resin, polymer the side chain of which has radical-curable unsaturated bonds, unsaturated urethane resin and the like are examples. As a result, even when high water resistance and high chemical resistance are requested, an obtained molded item can be used. Further, since filler is used in lamination without restriction, the cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing molded products such as bathtubs, washstands, and tiles that are required to have both aesthetic appearance and water resistance.

[Conventional technology]

Taking a bathtub as an example, after applying a colored gel coat, a Surf Ace mat was placed and laminated with a high resin content, and then the mat or roving was cut and laminated with resin to form a lining.

The use of surf-neath mats is an excellent method from the point of view of protecting the dull coat, but since it requires manpower to operate, it tends to be omitted from the perspective of cutting costs. Gradually, methods of obtaining molded products by directly performing spray-up molding also came to be adopted.

However, although the process is simplified, such a method has the drawback that it tends to cause poor appearance due to glass fiber slag, reducing the commercial value.

[Problem that the invention seeks to solve]

The present invention has been developed using fiber reinforced plastic molded products (hereinafter referred to as FR
This relates to a manufacturing method for obtaining a P-molded product (abbreviated as P-molded product).

[Means for solving problems]

That is, in the present invention, when a mold is coated with a gel coat and a molded product is obtained by backing molding using a combination of glass fiber and a radical curing resin, glass flakes are used as a filler in the next layer of the gel coat. The present invention provides a method for producing a molded article exhibiting excellent physical properties that eliminates the above-mentioned drawbacks by setting a mixture with a radical curable resin (hereinafter referred to as flake con-ground) as an intermediate layer.

[Effect]

To help understand the present invention, FIG. 1 shows a cross section of a molded product according to the present invention and the difference between it and a conventional FRP molded product.

It is well known that resin mixtures containing glass flakes as fillers are widely used as lining materials in the heavy-duty corrosion protection field, especially when the resin is a radical-curable polyester resin or vinyl ester resin.

A coating formed by stacking flat fillers, such as flakes, approximately 50 to 400 microns in size and 2 to 10 microns in thickness, significantly impedes the diffusion of moisture, air, chemicals, etc. into the coating film, and It is known that the diffusion coefficient is set to 17,100 or less, and this is known to exhibit anticorrosion properties by virtually reducing the time for moisture and air to reach the metal lump to zero.

However, flake compound cannot be used on the surface of FRP molded products. The chair used for face protection has not been found.

Furthermore, even if the flake compound is used as it is in the gel coat layer, the surface resin layer, which has only a small thickness, will flake off after boiling for a short time and lose its luster, resulting in no commercial value.

The inventors of the present invention investigated a method of utilizing the excellent protective effect of flake compound to protect gel coats, and unexpectedly found that they applied flake compound to the next layer of the gel coat layer, thereby increasing the required thickness. The inventors discovered that the object could be achieved by laminating glass fibers and radical curing resin, and were able to complete the present invention.

According to the present invention, if a resin with excellent water and chemical resistance is used for the flake compound next to the gel coat layer, the next laminated part will be suitable for fields that conventionally require high water and chemical resistance. It is possible to use a low-cost polyester resin in which orthophthalic acid, which could not be used, is modified as a modified acid, which is useful for reducing costs.

The glass flakes used in the present invention have a flat shape with a size of about 50 to 400 microns and a thickness of 2 to 10 microns as described above, such as glass flakes CF manufactured by Nippon Glass Fiber Co., Ltd.

Glass flakes are classified into several types depending on their particle size distribution, but for the present invention, it is preferable to use a type with many coarse particles and a wide particle size distribution.

Examples of resins useful in the present invention as radically curable resins used in flake compounds include unsaturated polyester resins, vinyl ester resins, polymers having radically curable unsaturated bonds in side chains, and unsaturated urethane resins. .

The mixing ratio of glass flakes and radical curing resin can be selected arbitrarily, but considering viscosity and painting workability, the mixing ratio of glass flakes (weight %) should be approximately 10 to 60%, preferably 20 to 40 chips. is suitable.

The gel coat resin used in the present invention may be the same or a different type of radical curing resin used for flake compounds.

As the laminating resin for the backing, a low-cost type ester resin can be used as described above. Of course, this does not preclude the use of the radical curable resin described above.

Fibrous reinforcing paper such as fiber reinforced paper is generally sprayed by cutting mats or rovings, but roving cloth or cloth can also be used if necessary.

When conventional high water resistance and chemical resistance are required,
Generally, no filler was mixed into the backing lamination resin. This is because it adversely affects the gel coat during boiling, causing blisters and cracks in the gel coat layer.

However, according to the present invention, such drawbacks can be overcome and fillers can be freely used in lamination, which is useful for reducing costs.

The filler for this purpose is not particularly limited, and commonly used fillers such as calcium carbonate, clay, water-containing alumina (aluminum hydroxide), fine silica powder, and pallite are selected as necessary.

〔Example〕

Next, examples will be shown below to help understand the present invention.

Example 1 Synthesis of bisphenol-type polyester resin (4) Stirrer, gas introduction pipe, thermometer, fractionation condenser'! i-attached L
Bisfe/-, I in a 7'c11 separable flask
116 g of 37011° fumaric acid was collected from the t/A propylene oxide adduct (the number of moles added of 7° lohylene oxide was 1 mol each) and esterified at 200 to 210°C in a nitrogen gas stream to give an acid value of 31. 6, 0.1 g of hydroquinone was added and poured into a metal vat to solidify. A pale yellow brittle solid unsaturated polyester was obtained.

100 parts of unsaturated polyester (the same weight below) was ground, added to 150 parts of styrene, and dissolved to obtain a bisphenol type polyester resin (5) having a Hazen color number of 300 and a viscosity of 4.9 poise.

Production of flake compound (,) To 1.00 parts of polyester resin (A), 50 parts of CF-18-i from Nippon Glass Fiber Co., Ltd., 2 parts of Erosil R-200t-2, and a cup from Union Carbide Co., Ltd. were added as glass flakes. Mix 2 parts of ring agent A-174 with a mixer,
Flake compound (a) was prepared by standing overnight.

Separately, to 100 parts of polyester resin (A), dirosyl R
A colored gel coat (b) was prepared by mixing 4 parts of -200 and 5 parts of Showa Koubun 5 Co., Ltd.'s Rizluck Color RC-62 (bluish green) as a coloring agent. On a glass plate treated with a mold release agent, add 100 parts of Kelcoat (b),
2 parts of methyl ethyl ketone oxide and 0.5 part of cobalt naphthenate were added to the coating to a thickness of 0.5 rr%m.

After heating at 60℃ for 30 minutes, flake compound (a
) 100 parts, 2 parts of methyl ethyl ketone luster oxide, and 0.5 parts of naphthenic acid conolate were added to a thickness of 1 r.
It was coated to a temperature of rVm and cured by heating at 60°C for 30 minutes.

As a polyester resin, a composition of 21 moles of propylene glycol, 1 mole of maleic anhydride, and 1 mole of phthalic anhydride was heated and esterified to obtain an unsaturated polyester with an oxidation rate of 35,4, and then a 40% polyester resin was prepared by weight including 3QOppm of hydroquinone. It was dissolved in styrene to produce polyester resin. Add 100 parts of this polyester resin to Erosil R-
2,001 parts of cobalt naphthenate and 0.5 parts of cobalt naphthenate were mixed, and immediately before use, 1 part of methyl ethyl ketone peroxide was added to prepare a backing resin.

On top of the flake compound layer, three layers of glass mat 350 and the aforementioned polyester resin for backing were laminated as a backing layer, and then a Mylar film was adhered and cured.

Post-cure by heating at 80°C for 2 hours and 120°C for 1 hour,
A test laminate (1) was manufactured.

Comparative Example 1 A laminate (II) was produced by molding in the same manner from the same sample, ie, only the gel coat (b) and the backing laminate, except that the flake compound (a) was not applied.

The gel coated surface was brought into close contact with a boiling test container having a hole of 100 Vm in diameter via a silicone rubber seal, and a continuous boiling test was conducted in boiling water at 98 to 100°C.

The results, as shown in Table 1, demonstrate that the results of the flake compound coated laminate (I) have the desired undulations.

Table 1 Example 2 Manufacture of side chain unsaturated bond type polymer (B) Manufacture of vinyl ester (C) A 21-hole rubber flask equipped with a stirrer, reflux condenser, thermometer, and gas inlet tube was used as an epoxy resin. 1050 with Epicoat 827 from Yuka Shell Epoxy Co., Ltd.
．． ! i2. Methacrylic acid 86g, trimethylbennolammonium chloride 311 hydroquinone 0.05
, FN and heated to 120-130°C for 90 minutes, the acid value became virtually zero, so styrene 364. @
In addition, a vinyl ester (C) having an epoxy group and a methacryloyl group in the molecule was obtained in the form of a pale yellowish brown liquid.

Separately, in a similar apparatus, 500 g of vinyl ester (C)
1 styrene 500. Mix ＠ and 1 in nitrogen gas stream.
Copolymerization was carried out at 30-135°C for 8 hours.

Add 140 g of methacrylic acid and 0.1 g of benzoquinone to the resulting polymer! Add i', 120 ~ in air stream
After reacting at 125°C for 4 hours, the acid value became 13.7, so styrene 180I was further added, and a polymer (Φ) having vinyl ester type unsaturated bonds in the side chain was made with a Hazen color number of 350 and a viscosity of 4. Obtained with 4 poise.

Production of gel coat (d) To 100 parts of polymer (B), add 4 parts of Erosil R-200.
1 part, 20 parts of titanium white, and 0.5 parts of phthalocyanine blue were added and kneaded with a roll to produce a scale coat (d).

Production of flake compound (,) 100 parts of polymer (B) and 3 parts of Erosil R-200 were kneaded with a roll, and then 60 parts of CF-150 from Nippon Glass Fiber Co., Ltd. was mixed in a mixer as glass flakes. A flake compound e) was produced.

Preparation of test piece Apply gel coat (d) 100 on a glass plate treated with a mold release agent.
A mixture of 2 parts of ≠328E from Kayaku Nouri Co., Ltd., 0.3 parts of cobalt nanthenate, and 50.2 parts of ethyl acetoacetate was added to a thickness of 0.4 to 0.5 rrv'm. Painted with percoater.

After heating at 60℃ for 30 minutes, flake consound (e
) A system prepared by adding 2 parts of 328E, 0.3 parts of naphthenic acid co-gel, and 0.2 parts of ethyl acetoacetate to 100 parts was roll coated to a thickness of about 1 rrv'm.

After curing by heating at 60°C for 30 minutes, a 158 fVT 10 of Orunphthalic acid-based polyester resin “Revolac” manufactured by Showa Kobunshi Co., Ltd. was used as the backing resin.
Methyl ethyl ketone i in 0 parts! - The system mixed with one part of oxide was back laminated using a 3f lie of glass mat $450.

After curing, the mixture was heated at 80°C for 2 hours and at 120°C for 1 hour to prepare a laminate.

Comparative Example 2 A laminate (2) was prepared by molding in the same manner as above except that the flake compound (e) was not used.

Using the same apparatus as in Example 1, a one-sided boiling test of the gel coat layer was conducted.

As shown in Table 2, the flake compound coated laminate (G) exhibited excellent properties.

Table 2 Example 3 Gel coat (d) containing the hardening agent of Example 2 was applied to a glass plate to a thickness of 0.5 rrv/m, heated at 60°C for 30 minutes, and then the hardening agent of Example 1 was added with gold. Apply flake co/pound (a)' to a thickness of about 1 rV/m, and
It was cured at 0°C for 30 minutes.

This was subjected to arrow stacking under the same conditions as in Example 1.

One side of the obtained laminate was subjected to continuous boiling using the same apparatus as in Example 1.

After 500 hours, no blisters or cracks were observed.

Example 4 Kelcoat (d) containing the curing agent of Example 2 was coated on a glass plate to a thickness of 0.5 m, 60 m thick.
After heating for 30 minutes at ℃, a vinyl ester flake compound was prepared using Lipoxy Flake FC- manufactured by Showa Kobunshi Co., Ltd.
100 of 83W (average glass flake content 30%)
In part, methyl ethyl ketone i? - Added 1.5 parts of oxide, painted to a thickness of 700 μm, and further applied after gluing Example 1
Backing lamination was carried out under the same conditions as above.

One side of the obtained laminate was subjected to continuous boiling using the same apparatus as in Example 1.

After 500 hours, no blistering or cracking was observed.

〔Effect of the invention〕

According to the method of the present invention, it is possible to produce FRP molded products with extremely excellent boiling resistance at low cost. Useful.

[Brief explanation of the drawing]

FIG. 1 is a drawing showing the cross-sectional structure of a laminate obtained by the method of the present invention and the conventional method.

Claims (1)

[Claims] When gel coating is applied to a mold and a fiber reinforcing material and a curable resin are used together to obtain a reinforced plastic molded product, a mixture of a radical curable resin containing glass flakes as a filler is added to the next layer of the gel coat as an intermediate layer. A method of producing a molded article, which comprises setting it up as layers.