JPS6261416B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is made of unsaturated polyester and vinyl ester resins, which are patterned by any molding method, have fibers as a reinforcing agent, and contain a polymerizable aromatic vinyl monomer as a copolymer component. The present invention relates to a method for producing a fiber-reinforced plastic molded article using at least one selected radical-curable resin as a binder.

Conventionally, fiber reinforced plastics (hereinafter referred to as FRP)
It would not be an exaggeration to say that this type (abbreviated as ) was put into practical use with almost no patterns added to it.

That is, even though bathtubs, septic tanks, ships, etc. are all colored, the current situation is that there are no patterns that can be called patterns.

In recent years, a method of manufacturing bathtubs using printed glass cloth by a hand lay-up method has been reported. However, the bathtubs manufactured using this method have an outstanding appearance and are much better than conventional bathtubs.
Although it surpasses the concept of FRP molded objects, unfortunately it can only be applied to limited molding methods and applications, and it has the drawback of being unable to be applied to mechanical molding methods, which have developed rapidly in recent years. .

As a result of repeated studies on a method to eliminate this drawback and to freely form any pattern regardless of the molding method, the inventor has found that a method that dissolves in the polymerizable aromatic vinyl monomer, which is one component of the resin, has been developed. A desired pattern is formed on a plastic film using a composition whose main components are a colorant and a binder, at least one of which does not dissolve in the monomer, and this printed film is applied during the production of FRP. The inventors have found that the object can be achieved by this, and have completed the present invention.

That is, the present invention provides an optional coating on a plastic film that is soluble in a polymerizable aromatic vinyl monomer, by using a composition mainly containing a colorant and a binder, at least one of which is not soluble in the polymerizable aromatic vinyl monomer. After forming the pattern, at least one radical curable resin selected from unsaturated polyester resins and vinyl ester resins containing the polymerizable aromatic vinyl monomer as a copolymerization component and a fiber reinforcing agent are applied thereto. The present invention relates to a method for producing a patterned fiber-reinforced plastic molded article, which comprises curing the molded article.

According to the method of the present invention, the printed plastic film is applied at a desired stage during the production of FRP, but the printed plastic film (hereinafter referred to as
The film (hereinafter referred to as "film") is dissolved in a polymerizable aromatic vinyl monomer (hereinafter referred to as "monomer"), and as a result, only the pattern remains in the uncured FRP without being dissolved. By curing at this stage, it becomes possible to obtain an FRP molded article with any desired pattern remaining.

Therefore, as long as the resin is not cured before the film is dissolved in the monomer, it is possible to give the molded article any desired pattern, regardless of the molding method. Film dissolution time is determined by film thickness,
Since it depends on the film material, temperature, type of monomer, etc., by adjusting these appropriately, it is possible to obtain a working time commensurate with the molding method and the molded product.

Furthermore, according to the method of the present invention, the dissolved film may precipitate into the resin during curing, resulting in cloudy appearance and impairing the appearance, but this can be minimized by selecting the material of the film. It can be stopped. When a filler is mixed into the resin to make the molded object opaque, the above-mentioned clouding phenomenon does not pose a particular problem.

It goes without saying that the films soluble in the monomers available for the present invention must be considered in the context of the monomers used. For example, as a film that can be dissolved in one or a mixture of two or more of monomers used in unsaturated polyester resins and vinyl ester resins, which are the most common radical-curing resins, such as styrene, vinyltoluene, and chlorostyrene. Examples include polystyrene and its copolymer film, polyvinyl acetate and its copolymer film, polyvinyl butyral film, polymethacrylate film, and polycarbonate film. In order for the pattern to remain in the molded article, at least one of the components, the colorant and the binder, must be insoluble in the monomers used. Most generally, water-soluble and alcohol-soluble types with poor oil solubility are desired.

Examples of binders include gum arabic, starch,
Examples include dextrin, casein, shellac, polyvinyl alcohol, polyacrylamide, acetyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, polyvinyl formal, polyvinyl acetal, and the like.

As the coloring agent, dyes or pigments can be used. Examples of dyes include direct dyes, acid dyes, basic dyes, acid mordant dyes, and reactive dyes. As the pigment, organic or inorganic pigments are used.

Specifically, for example, Chrysamine VG, Alizarin Yellow, Alizarin Sky Blue, Palatinchrome Brown, Acitraquinone Violet,
alizarin saphirole, alizarin pinole,
Chrysophenin, methylene blue, titanium white, carbon black, yellow lead, cadmium yellow, chrome vermilion, cadmium red, navy blue, ultramarine blue, iron oxide, azo pigments, azo lake pigments, phthalocyanine pigments, thioindigo pigments, anthraquinone pigments , anthraquinone lake, quinacridone pigment, irgazine pigment, dioxazine pigment, basic dye lake, acid dye lake,
These include mordant pigments and vat dyes.

Conventional printing methods such as gravure printing, screen printing, offset printing, letterpress printing, etc. can be used to print a desired pattern on a film that is dissolved in a monomer.

The method of the present invention can be applied to all methods of molding FRP. Specific molding methods include, for example, a hand lay-up method, a spray-up method, a bag method, a cold press method, a resin injection method, a sheet molding method (press molding), a prepreg combined die method, and the like.

The film can be easily dissolved if it is thin and its solubility parameters match those of the monomer, and by adjusting the curing time it can be dissolved before the resin is cured.

The surface of the film is usually preferred, but it can also be placed next to the surf ace mat or cloth.

The radical curable resin applicable to the present invention is
It is a type that has a radically polymerizable unsaturated bond in its molecule, and it always contains (1) α-β unsaturated polybasic acid as one component, and can be modified with any saturated acid or not. Unsaturated polyester resin in the form of an unsaturated alkyd obtained by esterification with alcohol dissolved in a copolymerizable monomer, (2) containing one or more acryloyl or methacryloyl group in one molecule and having a molecular weight of 300 or more. Examples include vinyl ester resins (epoxy acrylate resins) obtained by reacting certain epoxy resins with acrylic acid and/or methacrylic acid.

These resins use many types of monomers,
Some cured resins have excellent physical properties and can be used in a wide variety of applications. Further, as the curing method, room temperature curing, heat curing, photo curing, etc. can be used as needed.

The present invention is intended to be applied to the field of FRP by using reinforcing agents such as glass fibers and organic fibers in combination with resin, and in this case, fillers, colorants, mold release agents,
Of course, it is possible to arbitrarily use these methods together.

Next, examples will be shown below to help understand the present invention. In addition, parts in Examples indicate parts by weight.

Example 1 7 parts of pigment and 10 parts of hydroxypropylcellulose were placed on a polystyrene film with an average thickness of 30μ.
A white marble-like print with black and brown speckled patterns in some places was printed by a silk screen method using an ink consisting of 10 parts of polyvinylpyrrolidone and 73 parts of ethyl alcohol.

As unsaturated polyester resin, Showa Kobunshi Co., Ltd.
Rigorac 158BQT (monomer is styrene) manufactured by Co., Ltd. was used, and methyl ethyl ketone peroxide was mixed therein so that the gelation time was about 60 minutes.

This compounded resin is first applied to a thickness of 0.5 on cellophane.
m/m, and the printed film was immediately brought into close contact with the resin-coated surface. Immediately after the resin gels,
#450 pine 3 ply was hand lay-up molded using the same resin.

When the cellophane was peeled off after curing, a molded product with a beautiful translucent white marble-like pattern on the surface was obtained. Note that the dissolution time of the polystyrene film was 25 to 30 minutes.

Example 2 An ethylene-vinyl acetate copolymer having a composition of 51% ethylene and 49% vinyl acetate was dissolved in toluene and coated on a glass plate to form a film having an average thickness of 20 μm. Next, 10 parts of pigment, 10 parts of hydroxyethyl cellulose, 60 parts of isopropyl alcohol and water were added onto this film.
An abstract painting-like print was performed using a screen method using printing ink consisting of 20 parts.

Epicoat 828 is used as a vinyl ester resin.
350g, methacrylic acid 162g, benzyldimethylamine 2g, hydroquinone 0.2g composition from 130~
A resin obtained by adding 300 g of vinyltoluene to a resin having an acid value of 4.9 obtained by reacting at 135° C. for 3 hours was used.

A 30p Surf Ace mat was placed on cellophane, impregnated with the resin containing lauroyl peroxide so that the gelation time at 80°C was 4.5 to 5 minutes, and then the mat was covered with the printed film. Then, 3 plies of #450 swirl mat were laminated with the same resin. After leaving it for 1 hour, a mold release agent was applied and heated to 80-85℃.
Transfer to a circular tray mold with a depth of 15 m/m and 10 m/m.
After heating and pressurizing for 10 minutes under a pressure of Kg/cm ² , the mold was demolded. With a beautiful transparent abstract pattern
An FRP tray was obtained. Film dissolution time is
It took 40-50 minutes.

Example 3 Rigorakku manufactured by Showa Kobunshi Co., Ltd. was applied as an unsaturated polyester resin onto a polypropylene film.
100 parts of 2141, 10 parts of styrene, 1 part of magnesia
1 part tertiary butyl perbenzoate,
Add 1 part of zinc stearate and knead well with three rolls. Apply the mixture with a butter coater to a film thickness of 50 μm, immediately place a printed polystyrene film similar to that used in Example 1, and apply an additional 30 p.
Surf Ace Mat was placed, the above blended resin was added, and the mixture was squeezed with a roll to ensure uniform impregnation.

After that, 5 plies of #300 glass mat were mixed as a backing, and 70 parts of Rigoratsu 2141 was mixed as a resin.
30 parts of a 30% styrene solution of methyl methacrylate-methacrylic acid copolymer containing 3% (mole percentage) of carboxyl groups, 120 parts of calcium carbonate.
Each sheet was impregnated with a homogeneous mixture consisting of 1 part of magnesia, 1 part of tertiary butyl perbenzoate, and 4 parts of zinc stearate, stacked one on top of the other, and the back side was covered with a polypropylene film.

By leaving it at 40°C for 2 days, an SMC with a thickness of 2.5 mm was obtained that was completely free of stickiness even when the polypropylene film was peeled off (viscosity of 400,000 poise at 25°C).

This was placed in a tray-shaped mold with a diameter of 30 cm and a rising edge of 1 cm.
When molded for 5 minutes under heating and pressure of Kg/cm ² , a molded product with a translucent surface and a marble pattern was obtained.

Example 4 A polyvinyl alcohol mold release agent was applied to a wooden mold having a length of 400 mm, a width of 270 mm, a height of 120 mm, and a corner edge radius of 10 mm, and then dried. Next, an unsaturated polyester resin [manufactured by Showa Kobunshi Co., Ltd.,
After mixing 50 parts of Rigoratsuku 150HR], 50 parts of vinyl ester resin [Lipoxy VR-77, manufactured by Showa Kobunshi Co., Ltd.], 30 parts of styrene, 0.5 parts of cobalt naphthenate, and 2 parts of Erosil, the mixture was kneaded with rolls to achieve a uniform consistency. A dispersion liquid was prepared by adding 1.5 parts of methyl ethyl ketone peroxide as a curing agent to 100 parts of the resin in this dispersion liquid. This gel coat is spray-painted to a thickness of 0.5 to 0.7 mm, and after the surface is defoamed, it is placed on a 25μ thick polystyrene film using brass powder as a coloring agent and polyvinylpyrrolidone isopropyl alcohol solution as a coloring agent. A printed film with an offset print of the floral pattern of the button was pressed onto the top surface of the mold (which would become the bottom of the molded product) using ink.

The gelling time of the gel coat was about 36 minutes, during which time the film completely dissolved and the pattern remained.

Place 30p of Surf Ace Mat on this, add 100 parts of unsaturated polyester resin [manufactured by Showa Kobunshi Co., Ltd., Rigoratsuku 158BQT], Rigoratsuku Color RC#81.
(black) 5 parts, methyl ethyl ketone peroxide 1
Lined with a backing resin consisting of a #450
Three layers of mat were placed, impregnated with the above-mentioned backing resin, and cured.

When the mold was removed after curing, a beautiful molded product was obtained in which the flower pattern of the peonies appeared in a maki-e style on the bottom of the black molded product.

The pencil hardness of the hardened resin on the surface is 3H,
It had a hard and glossy appearance.

Comparative Example The same mold used in Example 4 was treated with a similar release agent. After applying a 50% xylene solution of polystyrene to this, a printed film similar to that used in Example 4 was pressure-bonded. The film dissolved quickly. After the stickiness disappeared (it took about 2 hours), lining was performed using the same recipe as in Example 4.

When removed from the mold after curing, the surface of the molded product has numerous small wrinkles caused by the polystyrene layer, and it is cloudy white and has low hardness, and is easily scratched with nails. The hardness was below HB and had no commercial value.

This is thought to be because the surface of the molded article is mainly made of polystyrene, and the difference from the molded article having the cured unsaturated polyester resin layer used in the present invention on the surface is obvious.

Claims (1)

[Claims] 1. An arbitrary pattern is formed on a plastic film that is soluble in a polymerizable aromatic vinyl monomer using a composition whose main components are a coloring agent and a binder, at least one of which is not soluble in the polymerizable aromatic vinyl monomer. After the formation, at least one radical curable resin selected from unsaturated polyester resins and vinyl ester resins containing the polymerizable aromatic vinyl monomer as a copolymerization component and a fiber reinforcing agent are applied thereto, and cured. A method for producing a patterned fiber-reinforced plastics molded article.