JPH0344883B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to marble, which is useful as tableware such as trays and tea cups, decorative items such as clock towers and ornaments, and interior items such as counters, wall materials, and mirror frames. This invention relates to a method for producing an unsaturated polyester resin molded article having a pattern.

[Conventional technology]

There is no known method for producing molded products with marble-like patterns by compression molding a molding material in which fillers, curing agents, internal mold release agents, reinforcing agents, pigments, etc. are mixed and dispersed in unsaturated polyester resin. There is. However, with this method, the molding material is washed away in the mold, so the colored part that should become the marble pattern spreads thinly, spreads too much and disappears, or becomes blurred, making it impossible to obtain the original color tone of the pigment. It also had the disadvantage of not being able to create a certain design pattern. Therefore, the compression molding method has not been widely used as a method for producing unsaturated polyester resin molded articles having marble-like patterns, and inefficient casting methods and gel coating methods have generally been used.

In recent years, colored fibrous materials produced by impregnating chopped strand fibers with pigments moistened with a liquid cross-linking agent are dispersed in unsaturated polyester resin compositions having a different color tone from the colored fibrous materials. , a method of compression molding the obtained molding material to obtain a molded product with a unique pattern has been proposed (Japanese Unexamined Patent Application Publication No. 1989-1999).
(See No. 129219). However, the molded products obtained by this method have a three-dimensional effect (depth) in the design.
The color is poor, and it is not clear, and there are smudges.
In addition, partial clumps (blocking) of the colored fibers are also observed, leaving problems such as undesirable aesthetics.

[Problem that the invention seeks to solve]

In view of the above situation, the present inventors developed a method for producing an unsaturated polyester resin molded product having a marble-like pattern by compression molding, which provides a clear pattern with a three-dimensional effect while avoiding blocking. As a result of various studies in order to obtain a marble pattern that does not exist, it has been found that these problems can be solved by the method of the present invention.

[Means for solving problems]

That is, the method for producing an unsaturated polyester resin molded article having a marble-like pattern according to the present invention includes: (1) a colored pigment moistened with an organic solvent;
(2) The colored fibers are obtained by impregnating a fibrous material with a colored solution obtained by mixing a solution of a thermoplastic polymer in a liquid crosslinking agent, taking it out, and drying it. It is characterized in that the molding material obtained by (3) mixing and dispersing different unsaturated polyester resin compositions is heated and press-molded in a mold.

[Effect]

The colored fibers used in the method of the present invention are obtained by moistening the colored pigment in an organic solvent and then mixing the fibrous material with a separately prepared solution of a thermoplastic polymer dissolved in a liquid crosslinking agent. Soak,
After being impregnated with a coloring solution, the fibrous material is taken out and subjected to a low-temperature drying process. Since the resulting colored solution has a low viscosity due to the use of an organic solvent, it is applied so as to wrap around each fibrous material. Furthermore, since the coloring solution has excellent drying properties, the finished colored fibers can be dried in a smooth state without blocking.

The colored fibers treated in this manner are mixed and dispersed in an unsaturated polyester resin composition having a different color tone from the colored fibers. Then, the obtained molding material is placed in a mold to obtain a desired molded product having a marble-like pattern. At this time, the colored fibers are prevented from blocking each other by the effective action of the thermoplastic polymer contained in the colored solution applied around them, and the colored fibers are prevented from blocking each other. It has the effect of preventing the marble-like design from bleeding and making the design stand out clearly.

The composition of the coloring solution is preferably 60-99.5% by weight
60-95% by weight of wet colored pigment, preferably 70-90% wetted with 40-0.5% by weight, preferably 30-5% by weight, colored pigment in 70-95% by weight organic solvent
% by weight and 5-50% by weight preferably 20-40% by weight
95-50% by weight of thermoplastic polymer preferably 80%
~40-5% of solution dissolved in ~60% by weight liquid crosslinker
It is preferably composed of 30 to 10% by weight.

As the coloring pigment used in the present invention, known organic and inorganic dyes and pigments can be used, but among them,
It is preferable to use one that has excellent heat resistance and transparency and does not significantly interfere with the curing of the unsaturated polyester resin. Suitable inorganic pigments include red iron, titanium oxide, cobalt, navy blue, cadmium, and the like. Similarly, organic pigments include soluble azo, insoluble azo, copper phthalocyanine, and cyclic higher pigments. Dyed pigments, especially India ink, are ideal because they contain pigment and do not bleed.

The organic solvent used in the present invention preferably has a relatively low boiling point and low viscosity. Suitable solvents include acetone, boiling point 56.2℃, methanol boiling point
64.8℃, ketones include acetone, methyl acetone, methyl ethyl ketone, diethyl ketone, ethers include tetrahydrofuran, methyl “Cellsolve”, “Cellsolve”, diethyl “Cellsolve”, diethyl “Carbitol”, esters include methyl acetate, ethyl acetate, Typical examples include isobutyl acetate, alcohols such as methanol, ethyl alcohol, and isopropyl alcohol, and halogen compounds such as methylene chloride, ethylene chloride, and propylene chloride.

The thermoplastic polymer used in the present invention is not particularly limited as long as it is thermoplastic. Typical examples include methyl methacrylate, ethyl methacrylate, butyl methacrylate, vinyl chloride, vinyl acetate, lauryl methacrylate, isoponyl methacrylate, acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, cellulose acetate butyrate. , cellulose acetate propinate, etc., polymers or copolymers obtained from polyethylene, polypropylene, polyamide, polyester, polystyrene, polybutazine, NBR, SBR, chloroprene rubber, and the like.

Suitable liquid crosslinking agents used in the present invention include methyl methacrylate, diallyl phthalate, methylstyrene, divicinylbenzene, alphachlorostyrene, and styrene.

The fibrous materials used in the present invention include synthetic fibers such as polyester, polyamide, and poval-based fibers;
Natural fibers such as hemp and cotton, and inorganic fibers such as carbon fiber and glass fiber are preferred. Among them, glass fiber is particularly preferred.

Glass fiber is made of Na ₂ O and
Alkali-free glass containing no alkali content of K ₂ O is preferable, and chopped strands are mainly used, and the length is 0.1 to 100 mm. The diameter of the glass fiber is preferably 0.01 to 50μ. Alkali-resistant glass fibers can also be specially used.

Colored fibers can be obtained by impregnating a fibrous material in the coloring solution according to a conventional method, taking it out, and drying it. The impregnation conditions are 0 to 40°C for 5 to 30 minutes, and the drying conditions are 20 to 80°C for 20 to 60 minutes.

The unsaturated polyester resin composition used in the present invention consists of an unsaturated polyester, a liquid crosslinking agent, glass fibers, fillers, and additives.

In order to make the marble-like pattern of a molded product rich in three-dimensionality (depth), the molded product must be made transparent. To this end, it is necessary to suppress the foaming that occurs during molding by minimizing the amount of liquid crosslinking agent, and it is also necessary to refrain from adding thickeners that impede transparency. However, if a thickener is not added, the material will lose its viscosity and the resin will not have adequate fluidity within the mold, so it is necessary to add as much thermoplastic polymer as possible to compensate for this. It goes without saying that this thermoplastic polymer also effectively acts as a known low shrinkage agent.

The molding material obtained by mixing and dispersing the colored fibers of different colors in such a highly transparent unsaturated polyester resin composition is charged into a mold and molded. The marble-like pattern created by the colored fibers on the base made of the polyester resin composition appears in depth with a three-dimensional effect, and when combined with the sharpness of the pattern woven by the colored fibers, it looks truly beautiful.

The composition of the unsaturated polyester resin composition is 50 to 80% by weight of unsaturated polyester.
10-20% by weight of unsaturated polyester resin dissolved in liquid crosslinking agent of 5-20% by weight of thermoplastic polymer
10% by weight, 5-20% by weight of glass fibers and 50-80% by weight of fillers.

The unsaturated polyester used in the present invention is obtained by reacting an unsaturated polybasic acid with a polyhydric alcohol, with or without a saturated polybasic acid, and is usually dissolved in a liquid crosslinking agent. It is commercially available in the form of unsaturated polyester resin.

Examples of the liquid crosslinking agent, thermoplastic polymer, and glass fiber to be blended into the unsaturated polyester resin composition include those described above.

In the unsaturated polyester resin composition of the present invention, when transparency is particularly important, it is optimal to use glass powder and aluminum hydroxide, which have good transparency, as fillers. Of course, other fillers can also be used. Examples of such fillers include calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, alumina, clay, kaolin, talc, diatomaceous earth, silica gel, mica powder, asbestos, and rock wool.

Furthermore, the unsaturated polyester resin composition of the present invention may contain small amounts of a curing agent, a stabilizer, a mold release agent, a pigment, and the like.

As the curing agent, an organic peroxide is used, and in the present invention, a curing agent that cures at a medium temperature of around 80° C. or higher is preferably used. Representative examples thereof include methyl ethyl ketone peroxide, cyclohexane peroxide, t-butyl hydroperoxide, cumene hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 2, 5-dimethyl-2,5-dihexane, t-butylperoxyacetate, t-butylperoxy 2-ethylhexanate, t-butylperoxybenzoate,
Examples include 2,5-dimethyl-2,5-dihexane.

Examples of stabilizers include quinones such as p-benzoquinone, naphthoquinone, phenanthraquinone, para-xyquinone, para-torquinone, 2,5-diphenyl-p-benzoquinone, 2,5-diacetoxy-p-benzoquinone, and 2,5-diacetoxy-p-benzoquinone. - dicaproxy-p-benzoquinone, hydroquinone as hydroquinones, pt-butylcatechol, 2,
5-di-t-butylhydroquinone, mono-t-
Butyl hydroquinone, phenols such as teriyabutyl para-cresol, hydroquinone monomethyl ether, organic and inorganic copper salts, copper naphthenate, amidines such as acetamidine acetate, acetamidine sulfate,
Examples of hydrazine salts include phenylhydrazine hydrochlorides and hydrazine hydrochlorides, and examples of quaternary ammonium salts include trimethylbenzylammonium chloride and laurylpyridinium chloride.

Examples of the mold release agent include zinc stearate, stearic acid, calcium stearate, and carnauba wax.

As the pigment, the same colored pigments as mentioned above can be used, but in that case, it is necessary to use different colored pigments.

The unsaturated polyester resin molded article having a marble-like pattern of the present invention is obtained by mixing and dispersing the colored fibers in an unsaturated polyester resin composition having a different color tone from the colored fibers according to a conventional method. It is obtained by heating and press-molding the material in a mold at a mold temperature of 130 to 160° C. and a molding pressure of 50 to 100 kg/cm ² .

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 The composition of the coloring solution is shown below. Glass fibers (length 25 mm) were once immersed in this coloring solution, the glass fibers were immersed in the coloring solution for 25 minutes, and then the glass fibers were taken out and heated at 70°C. Dry at low temperature in a dryer,
Made colored glass fibers. This glass fiber was coated around the glass fiber with a thermoplastic polymer and dried in a smooth state without blocking.

Composition of coloring solution Weight% Weight% Brown pigment acetone 25 75 70 High-pressure polyethylene styrene monomer 40 60 30 In this way, the treated colored glass fibers are treated with an unsaturated polyester resin (hereinafter referred to as , U.PE) composition using a kneader.

U.PE composition Weight% U.PE 20 Styrene monomer 20 Calcium carbonate 45 Glass fiber 12 Length 10mm Dicumyl peroxide 1 Zinc stearate 0.5 White pigment 1 Magnesium hydroxide 0.5 Then, the obtained molding material is placed in the mold. The mixture was heated and pressed at a mold temperature of 150°C and a molding pressure of 100 kg to obtain a molded product with an onyx-like marble pattern. The finished product was clear and beautiful, with no blocking of the colored glass fibers in the onyx-like pattern and no blurring of the design, and was sufficiently satisfactory in terms of strength and other qualities.

Example 2 Glass fibers (length 25 mm) were once immersed in the following coloring solution, and after being impregnated with the coloring solution for 30 minutes, the glass fibers were taken out and dried at a low temperature in a dryer at 60°C. Made colored glass fibers.

Composition of coloring solution Weight% Weight% Black pigment acetone 25 75 70 High pressure polyethylene styrene monomer 42 58 30 On the other hand, as a U.PE composition, U.PE was dissolved in a liquid resin in styrene monomer to have the following composition. The thermoplastic polymer and glass fiber were added and mixed with additives that did not specifically contain thickeners.

Composition of U.PE composition Weight% Weight% U.PE Styrene monomer 60 40 18 Polystyrene 8 Aluminum hydroxide 60 Glass fiber 11 Dicumyl peroxide 1 p-benzoquinone 1 Zinc stearate 0.5 White pigment 0.5 Add the above colored glass fiber to this The molding material obtained by mixing and dispersing the U.PE composition in a kneader is charged into a mold at a mold temperature of 130℃ and a molding pressure of 70Kg/
The product is molded under heat and pressure at ^cm2 , and the marble-like pattern created by colored glass fibers appears in depth with a three-dimensional effect on the base made of U.PE composition, which has no air bubbles and is highly transparent. Combined with the clarity of the design woven from the colored glass fibers, it looked truly beautiful.

In addition, other qualities such as strength are also fully satisfactory.

Comparative Example 1 The composition of the coloring solution is shown below, but in particular, the use of the solvent and thermoplastic resin polymer, which are the characteristics of the present invention, is not used.

Composition of the colored solution Brown pigment: 65% Styrene monomer: 35% Glass fibers (length 25 mm) were immersed in this colored solution for 25 minutes, then taken out and dried at a low temperature in a dryer at 70°C. This glass fiber had become blocked in some places. This colored glass fiber was mixed and dispersed in a U.PE composition having a different color tone as shown below using a kneader. This U.PE composition added more liquid crosslinking agent than Example 1 because transparency was not particularly important.
A new thickener was also added, and a thermoplastic polymer was added as a low-shrinkage agent.

Composition of U.PE composition Weight% Weight% U.PE Styrene monomer 60 40 19 Polystyrene 3 Calcium carbonate 60 Glass fiber 15 Dicumyl peroxide 1 p-benzoylquinone 0.5 Zinc stearate 0.5 White pigment 0.5 Magnesium hydroxide 0.5 Above A molding material obtained by mixing and dispersing colored glass fibers in a U.PE composition was placed in a mold and molded under heat and pressure under the same conditions as in Example 1. The product had a marble-like pattern with a three-dimensional effect. lacking (depth);
Furthermore, the image was not clear, blurred, smeared, and partially blocked in the colored fibers, which was not aesthetically pleasing.

〔Effect of the invention〕

With the method of the present invention, this has hitherto been considered difficult to achieve. By using the BMC method using U.PE compositions, it has become possible to stably produce molded products with a clear marble pattern with a three-dimensional effect.

Claims (1)

[Claims] 1 (1) A fibrous material is added to a colored solution obtained by mixing a colored pigment moistened with an organic solvent and a solution of a thermoplastic polymer dissolved in a liquid crosslinking agent. The colored fibers obtained by impregnation, extraction, and drying are mixed and dispersed in (2) an unsaturated polyester resin composition that has a different color tone from the colored fibers, and (3) the resulting molding material is heated in a mold. A method for producing an unsaturated polyester resin molded product having a marble-like pattern, which is characterized by pressure molding. 2. The unsaturated polyester resin composition according to claim 1, characterized in that the unsaturated polyester resin composition does not contain a thickener and consists of an unsaturated polyester, a liquid crosslinking agent, a thermoplastic polymer, glass fiber, and a filler. A method for producing an unsaturated polyester resin molded product having a marble-like pattern.