JPH04170348A - Resin composition for scagliola - Google Patents

Abstract

PURPOSE:To improve the surface hardness, weather and heat resistances of scagliola by incorporating a specified bifunctional unsatd. compd. into unsatd. polyester resin. CONSTITUTION:This resin compsn. is obtd. by blending 100 pts.wt. unsatd. polyester resin consisting of 50-80wt.% unsatd. polyester and 50-20wt.% polymerizable monomer such as styrene with 5-50 pts.wt. bifunctional unsatd. compd. represented by the formula (where each of R<1> and R<2> is H or methyl and X is -COOCH2- or -OCOCH2CH2OCO-), an inorg. filler such as CaCO3 and a curing agent such as t-butyl perbenzoate or by further adding a reinforcing agent, a shrinkage reducing agent, a curing accelerator, an internal releasing agent, a thickener, a colorant, etc., as required.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a resin composition for artificial marble.
The present invention relates to an unsaturated polyester resin composition for use in artificial marble, which not only has high surface hardness, but also has excellent weather resistance and heat resistance, and also has a deep appearance.

(Prior art) Conventionally, various fillers were blended into unsaturated polyester resin,
The hardened molded product is widely used as artificial marble for bathtubs, sink counters, kitchen counters, tables, etc. However, artificial marble made of unsaturated polyester resin as the base resin is made of acrylic resin,
Compared to those whose base resins are epoxy resins, phenolic resins, etc., they have lower surface hardness and are more prone to scratches on the surface, and also have insufficient heat resistance and weather resistance.

Therefore, in order to increase the surface hardness of molded products, conventional methods have been adopted such as blending high-hardness fillers into resin compositions or increasing the amount of fillers blended. This may deteriorate the moldability and workability of the resin composition, may impair the appearance of the molded product, and requires special equipment. On the other hand, methods such as providing a hard coat layer on the surface of the molded product are also known, but this method is inferior in productivity, provides a molded product with poor adhesiveness, and increases manufacturing costs.

(Issues to be Solved by the Invention The present invention was made to solve the above-mentioned problems in the production of conventional artificial marble, and it has not only high surface hardness but also excellent weather resistance and heat resistance. It is an object of the present invention to provide an unsaturated polyester resin composition capable of producing artificial marble having an excellent appearance and a deep appearance.

(Means for Solving the Problems) The resin composition for artificial marble according to the present invention is based on the general formula % formula % (wherein R1 and R2 are each independently hydrogen or methyl group, and X represents -COOCR1- or -COCLcnzoco-).

The unsaturated polyester resin usually consists of 50-80% by weight of unsaturated polyester and 50-20% by weight of polymerizable monomer. When the unsaturated polyester content is less than 50% by weight, artificial marble with sufficient strength cannot be obtained, while when it exceeds 80% by weight, the moldability and workability of the resin composition deteriorate.

An unsaturated polyester resin can generally be obtained by reacting an acid component, which is an α,β-unsaturated dibasic acid and/or its acid anhydride, with a polyhydric alcohol component.

Examples of the α,β-unsaturated dibasic acids include maleic acid, fumaric acid, itaconic acid, citraconic acid, and chlormaleic acid, and two or more of these may be used in combination. Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-phthanediol, neopentyl glycol, 1,6-hexanediol, triethylene glycol, hydrogenated bisphenol A, isopentyl glycol, Glycerin, trimethylolpropane, dicyclopentadiene, etc. can be mentioned. These may also be used in combination of two or more.

In the production of unsaturated polyester resins, a saturated dibasic acid and/or its acid anhydride may be used in combination as the acid component, if necessary. Such saturated dibasic acids include
Examples include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, succinic acid, azelaic acid, adipic acid, tetrahydrophthalic acid, hexahydrophthalic acid, chlorendic acid, tetrachlorophthalic acid, tetrabromophthalic acid, etc. can.

On the other hand, examples of polymerizable monomers include styrene, vinyltoluene, divinylbenzene, α-methylstyrene, chlorostyrene, dichlorostyrene, vinyl acetate, diallyl phthalate, diallyl isophthalate, diallyl terephthalate, etc., which are crosslinked with unsaturated polyester resins. Possible vinyl monomers, divinyl monomers, vinyl oligomers, etc. can be mentioned. Usually, styrene is preferably used.

In the present invention, specific examples of the trifunctional unsaturated compound include allyl (meth)acrylate and ethylene glycol di(meth)acrylate. Such a trifunctional unsaturated compound is an unsaturated polyester resin 1.
00 parts by weight, it is used in a range of 5 to 50 parts by weight. When the amount of the trifunctional unsaturated compound is less than 5 parts by weight per 100 parts by weight of the unsaturated polyester resin, it is impossible to obtain artificial marble with high surface hardness, and conversely, when the amount of the trifunctional unsaturated compound is less than 5 parts by weight based on 100 parts by weight of the unsaturated polyester resin, it is impossible to obtain artificial marble with high surface hardness. When the amount is too large, the resulting artificial marble has poor transparency and lacks a sense of depth.

The unsaturated polyester resin for artificial marble according to the present invention is
It usually contains an inorganic filler and a hardening agent, and if necessary, a reinforcing material, a low shrinkage material, a hardening accelerator, an internal mold release agent,
Contains thickeners, colorants, etc.

Examples of inorganic fillers include calcium carbonate, magnesium carbonate, barium sulfate, talc, clay, mica, silica, alumina, glass powder, aluminum hydroxide,
Magnesium hydroxide, agar stone, silica sand, etc. are used.

Among these, glass powder and aluminum hydroxide are preferably used from the viewpoint of enhancing the transparency of the resulting artificial marble.

As a curing agent, for example, t-butyl perbenzoate,
Organic filters such as benzoyl peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, t-butyl 6-oxy-2-ethylhexanoate, 1,1-di-t-butyl peroxycyclohexane, t-butyl peroxyisopropyl carbonate, etc. Oxides are used.

Examples of the reinforcing material include glass fibers, polyester fibers, phenol fibers, polyvinyl alcohol fibers, and carbon fibers, but glass fibers are usually preferably used.

In addition, examples of low shrinkage materials include polyethylene, polystyrene, polymethyl methacrylate, polyvinyl chloride,
Thermoplastic resins such as polyvinyl acetate, polycaprolactam, and saturated polyester, polybutadiene rubber, and polystyrene-acrylonitrile copolymers are used.

As the curing accelerator, metal salts of organic acids, particularly cobalt salts, such as cobalt naphthenate, cobalt octylate, cobalt acetylacetone, etc., are used.

As the internal mold release agent, higher fatty acids such as stearic acid and zinc stearate, higher fatty acid salts, alkyl phosphates, and the like are used.

Thickeners are substances that chemically bond with hydroxyl groups, carboxyl groups, ester groups, etc. possessed by unsaturated polyester, creating linear or partially cross-linked bonds to increase the molecular weight and thicken the unsaturated polyester resin. For example, diisocyanates such as toluene diisocyanate,
Metal alkoxides such as aluminum isopropoxide and titanium tetrabutoxide, divalent metal oxides such as magnesium oxide, calcium oxide, and bryllium oxide, and divalent metal hydroxides such as calcium hydroxide are used.

The resin composition for artificial marble according to the present invention is usually prepared by mutually dissolving or kneading the above-mentioned unsaturated polyester resin and the trifunctional unsaturated compound, and adding the above-mentioned inorganic filler and curing agent. , and other materials as required, such as a reinforcing material, a low shrinkage material, a curing accelerator, an internal mold release agent, a thickener, a coloring agent, etc.

Artificial marble can be obtained by molding and curing the resin composition for artificial marble according to the present invention, for example, by casting, pressing, hand lay-up molding, or the like.

(Example) The present invention will be explained below with reference to Examples.

Examples 1 to 8 Resin compositions having the compositions shown in Table 1 were prepared and molded at a molding temperature of 145°C, a molding pressure of 100 kgf/cm", and a molding time of 7 minutes to form a flat plate with a thickness of 6 cm. As shown in Table 1, the properties of this molded article are not only excellent in surface hardness, but also excellent in heat resistance and weather resistance.

Comparative Examples 1 to 3 A resin composition having the composition shown in Table 1 was prepared and molded under the same conditions as in Example 1 to obtain a flat plate with a thickness of 6n+m. The properties of this molded article are shown in Table 1.

As is clear from the results shown in Table 1, the resin composition of the present invention not only has excellent surface hardness;
Artificial marble with excellent heat resistance and weather resistance can be obtained.

(Effects of the Invention) As described above, the resin composition for artificial marble according to the present invention contains the above-mentioned trifunctional unsaturated compound together with the unsaturated polyester resin, which is polymerized alone in the resin composition during molding of the artificial marble. Alternatively, by copolymerizing with an unsaturated polyester resin or a polymerizable monomer, the surface hardness of the resulting artificial marble is increased, and the weather resistance and heat resistance are also improved. Furthermore, the resulting artificial marble is deeply mysterious.

Therefore, such a resin composition is suitable for use in, for example, bathtubs, washroom counters, kitchen counters, tables, and the like.

Patent applicant Sekisui Chemical Co., Ltd. Representative Hiro 1) Kaoru

Claims (2)

[Claims] (1) For 100 parts by weight of unsaturated polyester resin,
General formula R^1CH=CH-X-CH=CHR^2 (In the formula, R^1 and R^2 each independently represent hydrogen or a methyl group, and X represents -COOCH_2- or -OCOCH_2CH_2OCO-.) A resin composition for artificial marble, comprising 5 to 50 parts by weight of a bifunctional unsaturated compound represented by: (2) The resin composition for artificial marble according to claim 1, wherein the bifunctional unsaturated compound is allyl (meth)acrylate.