JPS63165109A - Manufacture of molded item - Google Patents

Abstract

PURPOSE:To make it possible to manufacture an excellent boilproof molded item at low cost by a structure wherein a mixture of radial-curing type resin and glass flakes as filter (or flake compound) is set as an intermediate layer next to a gelcoat layer in a molded item, in which both aesthetic sense and water resistance are requested in combination, such as a bathtub a washstand and tiles. CONSTITUTION:Flake compound is applied to a layer next to a gelcoat layer. Further, filler-filled resin is cast to the necessary thickness next to the flake compound layer. Preferable glass flakes used for flake compound are coarse particles and are the type having a wide distribution of particle diameters. Further, as radical-curing type resin, unsaturate polyester resin, vinylester resin, polymer, the side chain of which has radical-curable unsaturated groups, unsaturated uerthane resin and the like are examples. The mixing ratio of the glass flake and the radical-curing type resin in terms of the blending ratio (wt%) of the glass flakes is preferably about 10-60 %. As the resin for gelcoat and the casting resin for backing, radical-curing type resin or another kind of resin is used. As the filler to mix with the casting resin for backing, various materials are used in accordance with required physical properties.

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, the conventional method was to apply a colored gel coat and then line it with polyester resin and glass fiber to produce a single-colored, non-transparent bathtub. However, as the required appearance and performance have become more sophisticated, the manufacturing method has also changed.

For example, transparent celestial stone-like bathtubs are manufactured by applying a transparent gel coat, then lining and laminating with glass fiber and resin, and then casting with resin mixed with fillers, and this trend is increasing. can be seen.

There are also cases where gel coat is followed by casting without using glass fibers, spurring product diversification.

The problem is that such molded articles have insufficient hardness and boiling resistance at the levels of conventionally used gel coats.

That is, when hydrated alumina is used as a filler in a casting resin, the casting layer becomes white due to the action of hot water passing through the gel coat layer, which significantly impairs the appearance.

Furthermore, although vitreous fine powder fillers tend to be less prone to such whitening phenomenon, they often cause blisters in the gel coat layer, which has the drawback of completely reducing the product price.

[Problem that the invention seeks to solve]

The present invention relates to a method for manufacturing a molded article that, excluding the above-mentioned drawbacks, exhibits sufficient physical properties even in a single-sided boiling test, which is considered to be the most severe test, that is, a continuous boiling test in which only the gel coated surface is brought into contact with boiling water. It is.

[Failure to solve the problem]

That is, in the present invention, when a mold is coated with a gel coat and a molded product is obtained by backing molding with a filler-containing resin, the next layer of the gel coat is coated with a zocal-curing resin containing glass flakes as a filler. It is an object of the present invention to provide a method for producing a molded article exhibiting excellent physical properties in which the above-mentioned drawbacks are eliminated by setting a mixture (hereinafter referred to as flake powder) as an intermediate layer.

[Effect]

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

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.

Size like flakes, about 50-400 microns thick2
It is known that a paint film formed by stacking flat fillers of ~10 microns significantly impedes the diffusion of moisture, air, chemicals, etc. into the paint film, reducing the diffusion coefficient to 1/100 or less. It is known that this material exhibits anti-corrosion properties by virtually eliminating the time required for moisture and air to reach the metal substrate.

However, no example has been found in which a flake compound is used to protect the surface of a plastic molded product.

Furthermore, even if flakes, concrete or land are used as they are for the gel coat layer, the surface resin layer, which has only a small thickness, will flake off and lose its luster due to short boiling, resulting in no commercial value.

The present inventors investigated a method of utilizing the excellent protective effect of Flake Compound to protect Dullcoat, and unexpectedly found that they applied flake compound to the layer next to the Dullcoat layer. It was discovered that the object could be achieved by casting with a filler-containing resin having the required thickness, and the present invention was completed.

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

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

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 groups in side chains, and unsaturated urethane resins. .

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

As the gel coat resin and the backing casting resin used in the present invention, the same or different types of radical curing resins used in flake compounds can be used.

Various types of fillers are used depending on the required physical properties as the filler to be mixed with the lining casting resin.

When transparency is required, fine glass powder, hydrated alumina (aluminum hydroxide), fine silica powder, etc. are useful.

In particular, when mixed with resin to make a casting resin such as water-use alumina, the hardened cast product will immediately turn white when boiled, and this is not the case when a thick FRP layer is laminated next to the surface gel coat layer. As such, it also enables the use of fillers that have not been used until now.

If transparency is not required, calcium carbonate, clay,
Alumina, mica, pallite, gypsum, microballoon, etc. are selected as required.

Coloring is free.

〔Example〕

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

Example 1 Synthesis of bisphenol-type polyester resin mixture Bisphenol A 7'ropylene oxide adduct<7'ropylene oxide addition mole number is 3,701 moles each) and 116 moles of fumaric acid. Weigh out F,
After esterification was carried out at 200 to 210°C in a nitrogen gas stream to give an acid value of 31.6, 0.1.9% of hydroquinone was added and poured into a metal vat to solidify. A pale yellow, brittle, solid unsaturated ester was obtained.

100 parts of unsaturated polyester (same weight below) was ground, added to 50 parts of styrene, and dissolved to produce a bisphenol type polyester resin (4) with a Hazen color number of 300. A viscosity of 4.9 poise was obtained.

Production of flakes and lands (,) 100 parts of polyester resin (A), 50 parts of CF-18 from Nippon Glass Fiber Co., Ltd. as glass flakes, 2 parts of Elonor R-200, and a cup from Union Carbide Co., Ltd. Two parts of ring agent A-174 were mixed in a mixer and allowed to stand overnight to produce flake compound A-round (, ).

Separately, 100 parts of polyester resin (A) and 4 parts of Erosil R-200 were roll-kneaded to obtain Dull Coat (b).

Gluco) (b) 10 on a glass plate treated with a mold release agent
1.5 parts of Kayaku Nouri's Percadonox +16 in 0 parts
After coating the gel coat to a thickness of 0.5 m/m and heating it at 60°C for 30 minutes to dull the gel coat, add 100 parts of Flake Con/F Wound (a) and parka. The thickness of the system with 1.5 parts of Doxna 16 added is 1 m/i.
Paint so that the temperature is n and 60℃.

It was heated for 30 minutes to form a dal.

This is one side, and the other side has a thickness of 1 to 1.5 rrV/m.
As an FRP board (supported by a glass plate to prevent the FRP board from bending), 100 parts of polyester resin (T) was mixed with aluminum hydroxide manufactured by Showa Denko K.K. so that the thickness was about 8 ny'm. Product Name: Hisilite + 70 parts of H-317, 140 parts of H-110, 1 part of Noku Kadoxuna 16
80°C for 2 hours at 60°C.
Heat it for 2 hours to a thickness of about 10ψ, 300X300ny'
I made sure to use the m casting plate [■].

Comparative Example 1 A cast product [■] was the same sample except that it was not coated with flake powder (,), that is, a cast product using only gel coat (b) and casting resin.

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

As shown in Table 1, the results of the cast plate [I] coated with flakecon crand were proved to be extremely superior.

Table 1 Example 2 Production of unsaturated urethane resin Production of vinyl ester m m s A 911/Darapul flask equipped with a stirrer, a reflux condenser, and a thermometer was used as an epoxy resin manufactured by Yuka Shell Co., Ltd. Epicote 827 at 360#, methacrylic acid 1721.
) TJ methylbenzylammonium chloride 1.5
F, Hydroquinone 0.11! .

When reacted at 120 to 130'C for 3 hours, the acid value became 6.1, so 368 g of styrene was added.

Vinyl ester resin (a) was obtained in light reddish brown color.

H-forming unsaturated incyanate (b) in a 21cm grable flask equipped with a stirrer, a gas inlet tube with a drying device, a reflux condenser, and a thermometer.

350 g of propylene oxide adduct of bisphenol A (the number of moles of propylene oxide added is 1 mole each)
, inphoron diincyanate 444.9. Styrene 2
06.9. When 2.5 g of dibutyltin dilauret was charged and reacted at 70 to 75° C. for 6 hours in dry air, it was assumed that approximately 59% of the incyanato groups had reacted as a result of infrared analysis.

A pale yellow unsaturated isocyanate (b) was obtained.

21seiJ with similar equipment? In a rubble flask, 500 g of unsaturated incyanate (b), 100 g of vinyl ester resin (a) (1, 0.0 g of methylbarabenzoquinone)
After charging 15gk and reacting at 70 to 75°C for 6 hours, it was determined that free isocyanate groups had completely disappeared as a result of infrared analysis.

Styrene 550I was added to obtain an unsaturated urethane resin (B) having a Hazen color number of 350 and a viscosity of 6.8 poise.

Production of flake compound (C) 100 parts of unsaturated urethane resin (B), Erosil RX
4 parts of -200, 70 parts of CF-150 as glass flakes, 2 parts of the coupling agent (A-174) were initially mixed with Erosil in three rolls, and then the remaining ingredients were mixed in a mixer to form a flake compound (c). I did it.

Production of gel coat (d) To 100 parts of unsaturated urethane resin (B), add RX-200.
4 parts of phthalocyanine blue and 0.02 parts of phthalocyanine blue were roll-kneaded to obtain gel coat (d).

Preparation of test piece Apply Kelcoat (d) 1 on a glass plate treated with a mold release agent.
Add 1.5 parts of Nokukadox≠16 to 00 parts and add 0.3 parts
rrVn, 0.6 m/in and 1 m/m, respectively, using a bar coater, heated at 60°C for 30 minutes to form a gel, and then coated with flake compound (c) at a rate of about 1 rr.
It was coated to a thickness of v'm and heated at 60°C for 30 minutes to form a glue.

This is one side, and the other side is F with a thickness of 1 to 15 m/m.
Inphthalic acid-based RP board to have a thickness of approximately 8 m/m. Showa Kobunshisha 92156 as a reester resin
Add 100 parts of this resin to Noniichi Kadox + 16
and 200 parts of frit made by Nippon Ferro Co., Ltd. as a filler.
Obtained a 7m casting board.

Casting plate with gel coat thickness of 0.3 m/m [■]
, a casting plate with a shell coat thickness of 0.6 m/m [
■〕.

Casting plate [V] with Dull coat thickness 1.0 m/m
,.

Comparative Example 2 The same sample except that flakecon e-land (c) was not applied, that is, a cast product containing only gel coat (d) and casting resin, was similarly coated with gel coat according to the thickness of gel coat (d). A casting board [■] with a thickness of 0.3 m and 1 m,
A casting plate with a gel coat thickness of 0.6rrV/m [■
], gel coat thickness 1. Orry'm's casting board [■].

And so.

A single-sided boiling test was conducted using the same test device as in Example 1.

The results are shown in Table 2, and flakecon.
〇 (blank below) Table 2 Example 3 r Ruco used in Example 1) (b) 1.5 parts of Nono Kadox was mixed in 100 parts of the mixture, and the mixture was placed on a glass plate treated with a mold release agent so as to have a thickness of 0.5 parts. Flakeco/pound used (c)
The casting resin used in Example 2 was prepared by mixing 100 parts with 1.5 parts of Nono Kadox 16 and coating the mixture to a thickness of approximately 1%. A casting plate was manufactured in the same manner.

A one-sided boiling test showed no abnormalities even after 500 hours.

Example 4 Relcoat (d) containing the curing agent of Example 2 was coated on a glass plate to a thickness of 0.5 part at 60°C.

After heating for 30 minutes, as a vinyl ester flake compound, Lipoxy Flake FC-8 manufactured by Showa Kobunshi Co., Ltd.
Add 1.5 parts of methyl ethyl ketone/4'-oxide to 100 parts of 3W (average glass flake content 30 cm),
After coating and coating to a thickness of 700 μm, lining was laminated under the same conditions as in Example 1.

The obtained laminate (Vl) was continuously boiled on one side using the same apparatus as in Example 1.

After 500 hours, no blistering, cracking, or swelling was observed.

〔Effect of the invention〕

According to the method of the present invention, it is possible to produce a molded article exhibiting excellent boiling resistance at low cost.

It is extremely useful for applications that require aesthetic appeal and water resistance, such as bathroom vanities and tiles.

[Brief explanation of the drawing]

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

Claims (1)

[Claims] Gel coat is applied to a mold, and when a molded product is obtained by backing molding using filler-containing resin, a mixture with a radical curing resin containing glass flakes as a filler is set as the next layer of gel coat as an intermediate layer. A method for manufacturing a molded product consisting of: