JP2000053838A - Resin composition for artificial marble, its molding and method for bonding the molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition with improved initial adhesive strength for an artificial marble and a molding using the composition. SOLUTION: This resin composition for an artificial marble is one comprising an acrylic syrup, a filler and an alkaline earth metal compound, the alkaline earth metal compound having an average particle size of 0.5-15 μm and being added in an amount of 0.3-20 pts.wt. based on 100 pts.wt. of the acrylic syrup, and the average particle size D expressed in μm and the amount added W expressed in pts.wt. satisfying the inequality: D/W<10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for artificial marble, a molded article molded from the artificial marble resin composition, and a method for bonding the molded article. The present invention relates to a resin composition for artificial marble having improved initial adhesive strength to an adherend, a molded article thereof, and a method of bonding the molded article.

[0002]

2. Description of the Related Art Artificial marble has excellent texture and strength not inferior to natural marble, has good weather resistance, and has advantages that it can be easily constructed and processed as compared with natural marble. As such artificial marble, melamine decorative boards, gel coat artificial marble, acrylic artificial marble, polyester artificial marble, and the like have been conventionally known. Among them, acrylic artificial marble excellent in texture, strength, workability, weather resistance, and the like has been particularly noted.

Acrylic artificial marble obtained by blending a filler such as aluminum hydroxide with an acrylic syrup containing methyl methacrylate as a main component and hardening the same has been widely used for kitchen counters, vanities, tables, bathtubs and the like. Was. When bonding such an acrylic artificial marble to an adherend, a cyanoacrylate artificial marble instant adhesive that has been generally used requires a certain amount of time to obtain sufficient adhesive strength for actual use, When construction in a short time is required, insufficient initial adhesive strength becomes a problem. Here, the initial adhesive strength is the adhesive strength 30 minutes after the adherend is bonded in an atmosphere of 23 ° C. and 50%.

[0004] In order to solve such a problem, various improved techniques have been proposed from the viewpoint of adhesives. For example, JP-A-57-168971 proposes a technique for improving the initial adhesive strength by adding pyrogallol and a polyalkyl ether plasticizer to α-cyanoacrylate. JP-A-3-207779 proposes a curing accelerator composition for a cyanoacrylate instant adhesive containing a basic compound, a water-soluble organic solvent and water.

[0005] However, improvement of the initial adhesive strength is limited only by improving these adhesives. On the other hand, development and research of a resin composition for marble for improving the initial adhesive strength have hardly been performed so far.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide an artificial marble resin composition having an improved initial adhesive strength and a molded article using the composition. Another object of the present invention is to provide a bonding method for bonding the molded body to an adherend.

[0007]

According to the present invention, there is provided an artificial marble resin composition comprising an acrylic syrup, a filler and an alkaline earth metal compound, wherein the alkaline earth metal compound has an average particle size of 0%. 0.5 to 15 microns, and the addition amount is 0.3 to 100 parts by weight of acrylic syrup.
When D is 20 parts by weight, the average particle diameter is expressed in micron units as D, and the addition amount is expressed in parts by weight as W, the following formula (1) is satisfied. A resin composition for artificial marble is provided. D / W <10 (1)

In order to obtain a better initial adhesive strength, it is preferable to use magnesium hydroxide or magnesium oxide among the alkaline earth metal compounds.

Further, according to the present invention, there is provided a molded article molded from the resin composition for artificial marble.

Further, according to the present invention, there is provided a method for bonding a molded article, wherein the molded article is adhered to an adherend using a cyanoacrylate-based instant adhesive.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have conducted intensive studies as to whether the initial adhesive strength of artificial marble can be improved by improving the resin composition for artificial marble,
In the conventional acrylic artificial marble comprising an acrylic syrup and a filler, it has been found that by including a specific amount of an alkaline earth metal compound as a resin composition for artificial marble, the initial adhesive strength is significantly improved, and the present invention has been found. It is something that has been done. The alkaline earth metal compound used in the present invention, such as magnesium oxide or magnesium hydroxide, has been mixed in the artificial marble resin composition until now, but in such a case, the compound is used as a thickener. This is different from the idea of the present invention in which the compound is mixed as an initial bond strength improver. This is understood from the fact that the alkaline earth metal compound is added to the resin composition of the present invention even when the resin composition is molded by a casting method which does not originally require the addition of a thickener. Let's do it.

One of the great features of the resin composition for artificial marble according to the first aspect of the present invention is that an alkaline earth metal compound is added. The mechanism by which the alkaline earth metal compound is added to increase the initial adhesive strength with the adherend is not yet clear, but the alkaline earth metal compound catalyzes the anionic polymerization of cyanoacrylate instant adhesives. To promote the curing of the cyanoacrylate.

The amount of the alkaline earth metal compound added must be in the range of 0.3 to 20 parts by weight per 100 parts by weight of the acrylic syrup. 0.5 to 10 in the range
Part by weight is preferred, and 0.5 to 5 parts by weight is more preferred.
If the amount is less than 0.3 part by weight, the object of the present invention of improving the initial adhesive strength cannot be achieved, while if it is more than 20 parts by weight, the viscosity of the resin composition becomes too high and the workability deteriorates.

The alkaline earth metal compound must have an average particle size in the range of 0.5 to 15 microns. More preferably, it is 0.5 to 10 microns. If the average particle size is smaller than 0.5 micron, there is a problem that the appearance of the molded article is lost in transparency, while the average particle size is 1 μm.
If it is larger than 5 microns, the effect of improving the initial adhesiveness will not be obtained unless it is added in an amount of 20 parts by weight or more, and the compound viscosity will increase, resulting in poor workability.

Further, the ratio D / W between the average particle diameter D and the amount of addition W is D / W.
Needs to satisfy the expression (1). That is, according to such a formula, when using an alkaline earth metal compound having a large average particle size, it is necessary to increase the amount of addition,
On the other hand, when an alkaline earth metal compound having a small average particle size is used, it can be seen that the amount of addition can be reduced.
When D / W is 10 or more, there is a problem that the effect of improving the initial adhesive strength is small.

The acrylic syrup used in the present invention is obtained by dissolving an acrylic polymer obtained by polymerizing a polymerizable monomer having an acrylic monomer as a main component in the acrylic monomer. The acrylic syrup may be a syrup containing a polymer containing a polymerizable monomer having a carboxyl group, and in that case, the acid value is preferably 20 or less.

As the polymerizable monomer used for producing the acrylic polymer, an acrylate ester is mainly used, and other polymerizable monomers are used if necessary. The acrylic ester is not particularly limited, and may be appropriately selected and used according to the required characteristics of the target molded article. For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, glycidyl (meth) Acrylate and the like.
Species or two or more can be used. Among the above-mentioned acrylates, acrylates containing methyl methacrylate and methyl methacrylate as main components can be obtained from various physical properties such as weather resistance, transparency, surface gloss and appearance, and a molded article excellent in safety. Is particularly preferred.

Other polymerizable monomers that can be used in combination with the above acrylic acid ester include styrene, α-methylstyrene, vinyltoluene, chlorostyrene, vinyl acetate, allyl alcohol, ethylene glycol monoallyl ether, and propylene glycol monoallyl. Allyl ether or a compound having a polymerizable double bond and a carboxyl group in the molecule, for example, unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, etc. Saturated dicarboxylic acids or their mono- or diesters can be mentioned, and one or more of these can be used.

As the polymerization-reactive acrylic monomer used together with the above-mentioned acrylic polymer, the acrylic monomers exemplified as those used in the production of the above-mentioned acrylic polymer may be mentioned again as preferred ones. Other polymerizable monomers that can be used together with these acrylic monomers include, for example, styrene, α-methylstyrene, vinyl toluene, chlorostyrene, vinyl acetate, acrylamide, acrylonitrile, allyl alcohol, ethylene glycol monoallyl ether, propylene Glycol monoallyl ether or a compound having a polymerizable double bond and a carboxyl group in the molecule, for example, unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, etc. Of unsaturated dicarboxylic acids or It can be mentioned those mono- or diesters or the like, it is possible to use one or more of these.

Further, depending on the required properties of the obtained molded article, a crosslinking reactive monomer may be used in combination, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate. Polyfunctional (meth) acrylates such as acrylate, dipropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, divinylbenzene, diallyl phthalate , Diallyl isophthalate, triallyl cyanurate, triallyl isocyanurate and the like can be used alone or in combination of two or more.

When the above-mentioned acrylic syrup is used, a polymerization initiator such as benzoyl peroxide, lauryl peroxide, methyl ethyl ketone peroxide, t-butyl peroxybenzoate, cumene hydroperoxide, cyclohexanone peroxide or the like is usually used. An azo compound such as azobisisobutyronitrile and the like are added, and further, if necessary, a reinforcing agent and the like are added, so that the mechanical strength of the obtained molded article can be increased.

The alkaline earth metal compounds used in the present invention include magnesium, calcium, strontium,
Oxides, hydroxides, carbonates and the like of alkaline earth metals such as barium and radium. Among these, magnesium oxide and magnesium hydroxide are particularly preferable because the initial adhesive strength shows a remarkable improvement.

The filler usable in the present invention is not particularly limited. Examples thereof include aluminum hydroxide, calcium carbonate, barium sulfate, alumina, clay, talc, milled fiber, silica, river sand, diatomaceous earth, mica powder, gypsum,
Inorganic or organic fillers such as fluorite, asbestos powder, glass powder, glass spheres, polymer beads and the like can be mentioned, and among them, aluminum hydroxide is particularly preferable. The amount of the filler used is preferably 50 to 300 parts by weight, more preferably 100 to 250 parts by weight, and even more preferably 150 to 200 parts by weight per 100 parts by weight of the acrylic syrup. If the amount of the filler is less than 50 parts by weight, the surface hardness and rigidity of the molded article may be insufficient. On the other hand, if the amount is more than 300 parts by weight, the viscosity of the resin composition for artificial marble becomes too high, and the workability may be deteriorated. The average particle size of the filler is usually 0.1 to 100 microns, preferably 0.5 to 100 μm.
50 microns. When the average particle size is less than 0.1 micron, the transparency of the molded product may be lost or the filling amount may be restricted. On the other hand, if it is larger than 100 microns,
Fine spots appear on the obtained artificial marble, which may impair the aesthetic appearance.

In order to give the artificial marble an appearance such as stone texture, a decorative material may be further added to the resin composition for artificial marble of the present invention. Decorative materials can be transparent or opaque, or colored or uncolored.For example, calcined talc, biotite, carborundum, anhydrite, sandstone, vermiculite, natural granite, basalt, quartz, malachite, Marble, mica, obsidian,
Mineral particles such as opal, quartz rock, rock gypsum, sand, silica, wollastonite (ullastonite); bricks, plaster, pottery, sawdust, shells, glass; epoxy resin, polyethylene resin, ethylene copolymer, melamine resin, Phenolic resin, polyacetal, polyester, polypropylene,
Chips of insoluble or crosslinked polymers, such as urea / formaldehyde resins, polyureas, polyurethanes, polyvinylidene chlorides, polyvinyl esters, with or without fillers, or with or without pigments. Further, particles of a semi-cured material described below may be used as a decorating material.

The semi-cured product used as a decorating material has a reactive group or contains a reactive monomer in the polymer itself, so that a curing reaction can be further carried out and a partially three-dimensionally crosslinked product has already been obtained. And a polymer having a three-dimensional cross-linking bond swollen with a liquid radical polymerizable monomer.

This semi-cured product is usually rubbery and moderately soft, since the polymer is three-dimensionally cross-linked to a low density and swollen with a liquid radical polymerizable monomer, and can be easily applied with a relatively small force. It can be crushed to a predetermined size. In addition, since the liquid monomer contained in the polymer is cured by a radical reaction, the mixture of the semi-cured product and the liquid radical polymerizable curable resin or only the semi-cured product is cured, and thus the particles at the particle interface are hardened. A cured product having high adhesive strength can be obtained. In addition, since the semi-cured product has an appropriate strength, the shape of the crushed surface can be maintained, and a desired pattern can be developed.

A typical example of such a semi-cured product is “a compound a having a plurality of reactive substituents and a compound b capable of reacting with the compound a are bonded by a reaction other than a radical reaction. Composition comprising a reactive compound and a liquid monomer A which can be polymerized by a radical polymerization reaction "
Can be mentioned.

Examples of the compound a include a monomer having two or more hydroxyl groups and carboxyl groups as reactive substituents in one molecule and a polymer thereof. Examples of the monomer include ethylene glycol. , Diethylene glycol, 1,4-butanediol, neopentyl glycol, trimethylolpropane, polyhydric alcohols such as bisphenol A; malonic acid, adipic acid, isophthalic acid,
And polycarboxylic acids such as terephthalic acid. Examples of the polymer include a vinyl ester resin; an unsaturated polyester resin; a saturated polyester resin; a polymer of an acrylic compound such as 2-hydroxyethyl methacrylate; an aromatic vinyl compound such as styrene and α-methylstyrene; and an acrylic compound. And the like.

Compound b is a so-called thickening compound, for example, polyfunctional isocyanate compounds such as tolylene isocyanate, hydrogenated tolylene diisocyanate, methylene diisocyanate, hexamethylene diisocyanate; and organic aluminum compounds such as aluminum isopropoxide. No.

Examples of the liquid monomer A include conventionally known various monomers, for example, aromatic vinyl compounds such as styrene and α-methylstyrene; methyl (meth)
Acrylic compounds such as acrylate, isobutyl (meth) acrylate, ethylene glycol di (meth) acrylate, and trimethylolpropane tri (meth) acrylate are exemplified. Among these, polyfunctional (meth) acrylates such as methyl (meth) acrylate, ethylene glycol di (meth) acrylate, and trimethylolpropane tri (meth) acrylate are preferable because of their excellent reactivity.

The method of mixing the compounds a and b and the monomer A and the order of mixing are not particularly limited.
After mixing, the compounds a and b are reacted, and the obtained reaction compound (composition) is conveniently crushed to a predetermined size to form particles.

To the reaction compound (composition), a filler such as mica, calcium carbonate, aluminum hydroxide and the like, a coloring agent and the like can be added. Various patterns can be formed by appropriately adjusting the colorant according to a desired pattern. The colorant may be uniformly mixed with the reaction compound (composition), or may be mixed unevenly so as to form a streak-like or cloud-like pattern.

If necessary, a reinforcing agent, a low-shrinking agent, a release agent, a coloring agent, etc. may be added to the artificial marble resin composition of the present invention as long as the effects of the present invention are not impaired.

Examples of the reinforcing agent include inorganic fibers such as glass fibers, carbon fibers, metal fibers, and ceramic fibers; synthetic fibers such as aramid, polyester, and polyamide; regenerated fibers; and organic fibers including natural fibers. These can be used alone or in combination of two or more. As the fiber form, for example, roving, chopped strand, mat, cloth (woven fabric, knitted fabric) and the like can be used.

Polyethylene, polypropylene, polystyrene, polyethylene glycol,
Polypropylene glycol, cellulose butyrate, acetate, polyvinyl chloride, polyvinyl acetate, polycaprolactam, saturated polyester, or a thermoplastic polymer such as a copolymer thereof, and the like can be mentioned. Dimensional accuracy can be achieved.

The release agent is not particularly limited, and examples thereof include stearic acid, zinc stearate, aluminum stearate, calcium stearate, barium stearate, stearic acid amide, alkyl phosphate, and silicone oil. By mixing the agent, the mold can be easily separated from the mold.

The colorant is not particularly limited, and a known colorant such as an inorganic pigment or an organic pigment can be used.

The resin composition for artificial marble of the present invention can be molded by any of a casting method and a press molding method. The resin composition when molded by a casting method will be described below.

The (meth) acrylic polymer such as polymethyl methacrylate contained in the acrylic syrup is 5
The amount is preferably from 40 to 40 parts by weight, and the content of the (meth) acrylate-based monomer is preferably from 95 to 60 parts by weight. When the amount of the (meth) acrylate-based monomer is less than 60 parts by weight, the viscosity of the acrylic syrup becomes too high, and the workability deteriorates. On the other hand, when the amount of the (meth) acrylate-based monomer is more than 95 parts by weight, the shrinkage during curing becomes too large.

The amount of the filler used is preferably 100 to 300 parts by weight when, for example, aluminum hydroxide is used.

The resin composition for artificial marble of the present invention can be used in various forms such as kitchen counters, vanities, bathtubs, tables, wall materials, flooring materials, furniture, interior accessories, seals, etc., by molding methods such as the casting method described above. It is molded into various forms and used for various purposes.

The mold used in the present invention may be made of any material, for example, as long as it is made of iron, aluminum, resin or the like.

When the molded article is attached to an adherend, a cyanoacrylate instant adhesive is preferably used as the adhesive. This is because the alkaline earth metal compound contained as the resin composition acts as a catalyst for the anionic polymerization of cyanoacrylate and promotes the curing reaction of cyanoacrylate.

The cyanoacrylate-based instant adhesive used in the present invention contains 2-cyanoacrylate represented by the following general formula (1) as a main component.

[0045]

Embedded image

Wherein R is an alkyl group, an alkenyl group,
It is a cyclohexyl group, an aryl group or an alkoxyalkyl group. )

Specific examples of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group,
Alkyl groups such as isobutyl group; alkenyl groups such as vinyl group and allyl group; aryl groups such as phenyl group, tolyl group and naphthyl group; and alkoxyalkyl groups such as methoxyethyl group, ethoxyethyl group and methoxypropyl group.

A known curing accelerator may be used in combination with the cyanoacrylate instant adhesive.

[0049]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples. In the examples, "part" and "%"
Unless otherwise specified, “parts by weight” and “% by weight” are used, respectively.
Shall be expressed.

The average particle size was measured using a pore-passing type particle size distribution analyzer "CULTER MULTISIZER II".

Example 1 100 parts of a methyl methacrylate solution in which 30% of polymethyl methacrylate having a weight average molecular weight of about 70,000 was dissolved (hereinafter referred to as "acryl syrup") was used.
Ethylene glycol dimethacrylate 3 parts, average particle size 2
180 parts of 5-micron aluminum hydroxide (“CW-325LV” manufactured by Sumitomo Chemical Co., Ltd.), 1.8 parts of a silane coupling agent (“KBM-503” manufactured by Shin-Etsu Chemical Co., Ltd.), and an average obtained by grinding with a ball mill. Magnesium hydroxide with a particle size of 2.3 microns (“MS-4” manufactured by Tomita Pharmaceutical Co., Ltd.)
3 parts and 1 part of t-butyl peroxy-2-ethylhexanoate ("Kayaester O" manufactured by Gunpaku Akzo Co., Ltd.) as a curing catalyst were added and mixed, followed by vacuum degassing to prepare a resin composition for artificial marble. . This composition was poured into a cell having a 30 cm square aluminum plate and a 12 mm thick silicon rubber gasket interposed therebetween, and was cured by leaving it in an oven at 80 ° C. for 1.5 hours. Then 130 ° C, 2
The mixture was cured in an oven for an hour to obtain a marble-like molded product.

In order to examine the adhesive strength of this molded product, the following breaking strength was measured. At the same time, workability was evaluated. Table 1 shows the results.

(Measurement of breaking strength) 50 mm × 7
A plurality of test pieces of 5 mm × 12 mm were prepared, and the test pieces were adhered to each other with an adhesive area of 50 mm × 75 mm using an instant marble adhesive (“Alon Alpha (artificial marble)” manufactured by Toagosei Chemical Co., Ltd.). After that, the temperature was 23 ° C and the humidity was 50.
% For 30 minutes, and a load was applied perpendicularly to the bonding surface based on the bending test method specified in JIS K-6911, and the load when peeling of the bonding surface occurred was defined as the breaking load. Although a breaking load of 500 N or more was used as a criterion for determining the adhesive strength in the present invention, it is necessary that the breaking load be 1,000 N or more in actual use.

(Workability) ：: Compound kneading is easy and there is no problem in casting work. X: Compound kneading work is difficult.

Example 2 In Example 1, the amount of magnesium hydroxide added was 20
A molded body was obtained by the same method except that the parts were used. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 3 A molded product was obtained in the same manner as in Example 1 except that 1 part of magnesium hydroxide having an average particle size of 9.4 μm (“Kyowa Suimag F” manufactured by Kyowa Chemical Industry Co., Ltd.) was added. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 4 A molded product was obtained in the same manner as in Example 3 except that the addition amount of magnesium hydroxide was changed to 20 parts. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 5 A molded product was obtained in the same manner as in Example 1 except that 1 part of a white toner (“AT-3” manufactured by Dainichi Seika Kogyo Co., Ltd.) was further added.
This compact was pulverized with a jaw crusher and a hammer mill, and then classified into 30 to 40 mesh and 40 to 100 mesh to obtain white pulverized particles.

Similarly, a black toner (“A” manufactured by Dainichi Seika Kogyo Co., Ltd.)
T-256 ") A molded product was obtained in the same manner as in Example 1 except that 2 parts of T-256 was further added. This compact was pulverized with a jaw crusher and a hammer mill, and then classified into 30 to 40 mesh and 40 to 100 mesh to obtain black pulverized particles.

Acrylic syrup 71 parts, methyl methacrylate 29 parts, ethylene glycol dimethacrylate 3
Part, aluminum hydroxide (CW-3 manufactured by Sumitomo Chemical Co., Ltd.)
25LV ") 130 parts, 0.3 part of magnesium hydroxide having an average particle size of 2.3 microns obtained by ball milling (" MS-4 "manufactured by Tomita Pharmaceutical Co., Ltd.), a silane coupling agent (Shin-Etsu Chemical Co., Ltd.) "KBM-503") 1.8 parts, 30
25 parts of the white particles of 40 to 40 mesh, 10 parts of the white particles of 40 to 100 mesh, 3.5 parts of the black particles of 30 to 40 mesh, and the black particles of 40 to 100 mesh.
5 parts and 1 part of t-butylperoxy-2-ethylhexanoele ("Kayaester O" manufactured by Gunpaku Akzo Co., Ltd.) as a curing catalyst were dispersed and mixed, followed by degassing under vacuum.
In the same manner as described above, a cured product was obtained.

The surface of the obtained molded body was polished with a belt sander by about 0.5 mm to obtain a stone-like molded body. The fracture strength and workability of the obtained stone-like molded product were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 6 A grain-like molded product was obtained in the same manner as in Example 5 except that the addition amount of magnesium hydroxide was changed to 20 parts. The fracture strength and workability of the obtained stone-like molded product were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 7 A molded product was obtained in the same manner as in Example 5 except that one part of magnesium hydroxide having an average particle size of 9.4 μm (“Kyowa Suimag F” manufactured by Kyowa Chemical Industry Co., Ltd.) was added. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 8 A molded article was obtained in the same manner as in Example 7, except that the amount of magnesium hydroxide was changed to 20 parts. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 9 In Example 1, calcium carbonate ("Whiteton P" manufactured by Toyo Fine Chemical Co., Ltd.) was used instead of magnesium hydroxide.
-30 "), and a molding was obtained in the same manner except that the amount of addition was 1 part. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 10 A molded article was obtained in the same manner as in Example 9 except that the amount of calcium carbonate added was changed to 2 parts. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 11 A molded product was obtained in the same manner as in Example 9 except that the amount of calcium carbonate added was changed to 3 parts. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 12 A molded product was obtained in the same manner as in Example 9 except that the amount of calcium carbonate added was changed to 5 parts. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 13 In Example 1, magnesium oxide (Kyowa Mag # 10 manufactured by Kyowa Chemical Co., Ltd.) was used instead of magnesium hydroxide.
0 "), and a molding was obtained in the same manner as above except that the added amount was 1 part. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 14 A molded product was obtained in the same manner as in Example 13, except that the addition amount of magnesium oxide was changed to 2 parts. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 15 A molded product was obtained in the same manner as in Example 13, except that the addition amount of magnesium oxide was changed to 3 parts. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 16 A molded product was obtained in the same manner as in Example 13, except that the addition amount of magnesium oxide was changed to 5 parts. The breaking strength and workability of this molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 1 A molded product was obtained in the same manner as in Example 1 except that magnesium hydroxide was not added. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 2 A molded product was obtained in the same manner as in Example 7 except that magnesium hydroxide was not added. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 3 Example 4 except that 0.1 part of magnesium hydroxide was added.
A molded body was obtained in the same manner as described above. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 4 Example 7 except that 0.1 part of magnesium hydroxide was added.
A molded body was obtained in the same manner as described above. The breaking strength and workability of the obtained molded body were measured and evaluated in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 5 In Example 1, the addition amount of magnesium hydroxide was changed to 50.
A resin composition was prepared in the same manner as above except for the parts. However, since the viscosity of the resin composition was significantly increased, workability was deteriorated, and a molded article could not be obtained.

Comparative Example 6 A resin composition was prepared in the same manner as in Example 4 except that the amount of magnesium hydroxide was changed to 50 parts. However, since the viscosity of the resin composition was significantly increased, workability was deteriorated, and a molded article could not be obtained.

Comparative Example 7 A resin composition was obtained in the same manner as in Example 7 except that the addition amount of magnesium hydroxide was changed to 50 parts. However, since the viscosity of the resin composition was significantly increased, workability was deteriorated, and a molded article could not be obtained.

Comparative Example 8 A resin composition was obtained in the same manner as in Example 10, except that the amount of magnesium hydroxide was changed to 50 parts. However, since the viscosity of the resin composition was significantly increased, workability was deteriorated, and a molded article could not be obtained.

[0081]

[Table 1]

Examples 1 to 16 in which 0.3 to 20 parts of an alkaline earth metal compound having an average particle size of 0.5 to 15 μm are added to 100 parts of acrylic syrup and satisfying the formula (1) According to the resin composition for artificial marble described in (1), excellent initial adhesive strength with a breaking load of 500 N or more was obtained. On the other hand, in Comparative Examples 1 and 2 in which the alkaline earth metal compound was not added, the destruction load was 372 N, and peeling of the bonded surface occurred with a lighter load than in the examples. Also, in Comparative Examples 3 and 4 in which the amount of the alkaline earth metal compound added was smaller than the specified range of the present invention, peeling of the bonded surface similarly occurred with a lighter load than in the examples. On the other hand, in Comparative Examples 5 to 8 in which the amount of addition was larger than the specified range of the present invention, the viscosity of the resin composition was too high and the workability was poor.

[0083]

According to the resin composition for artificial marble of the present invention, the initial adhesive strength of the molded article to the adherend can be improved. Further, by using a cyanoacrylate-based instant adhesive as the adhesive, a further initial adhesive strength can be obtained.

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Claims (4)

[Claims] 1. An artificial marble resin composition comprising an acrylic syrup, a filler and an alkaline earth metal compound, wherein the alkaline earth metal compound has an average particle size of 0.5 to 15 microns and has an acrylic syrup 100%. When the addition amount with respect to parts by weight is 0.3 to 20 parts by weight, and the numerical value representing the average particle size in microns is D, and the numerical value representing the addition amount in parts by weight is W, A resin composition for artificial marble, characterized by satisfying the formula (1). D / W <10 (1) 2. The artificial marble resin composition according to claim 1, wherein the alkaline earth metal compound is magnesium hydroxide or magnesium oxide. 3. A molded article formed from the resin composition for artificial marble according to claim 1 or 2. 4. A method for bonding a molded article, comprising: adhering the molded article according to claim 3 to an adherend using a cyanoacrylate-based instant adhesive.