JPS62128956A - Heat-resistant and hot water-resistant artificial marble - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to artificial marble that can be used as a building material with excellent heat resistance, particularly hot water resistance.

(Prior Art) Artificial marble using hydrated metal oxides as a filler has been known. For example, methyl methacrylate artificial marble is made by kneading aluminum hydroxide into methyl methacrylate sill and curing it using an organic peroxide as a curing agent, or unsaturated polyester resin sill or epoxy (meth)acrylate is used instead of methyl methacrylate sill. A method using a vinyl ester resin sill dissolved in styrene is known. These syrups are molded by being poured into molds of various shapes or between moving belts, and then heated to room temperature or a temperature of around 60°C. On the other hand, there are also known products that are molded under heat and pressure using a mold, for example, a mixture of unsaturated polyester resin, epoxy (meth)acrylate resin, and metal oxide hydrate with glass fiber and binder added. There is a premix molding material which gives a celestial stone-like article by adding 1η.

(Problems to be Solved by the Invention) However, the artificial marble cast using the above-mentioned silica has a high viscosity, so there are restrictions on the amount and size of the filler that can be used. be. For example, when making artificial marble with a high filler content that has excellent heat resistance and flame retardancy by using a large amount of filler, it is difficult to disperse the filler and a beautiful product cannot be obtained. In order to suppress the accompanying increase in viscosity, methods such as blending particles with a large particle size within a range that does not cause sedimentation have been adopted. Therefore, these artificial marbles are
Due to poor dispersion of the filler and the use of fillers with large particle sizes, water seeps through surface cracks, causing whitening in a short period of time when immersed in boiling water, resulting in loss of aesthetic appearance. In order to prevent this, unsaturated polyester resins and vinyl ester resins are coated with a gel coat. However, gel-coated products have poor heat resistance,
It had drawbacks such as blistering caused by cigarette burns and hot water, resulting in defects that were extremely difficult to repair.

In addition, artificial marble that is heated and pressure-molded using premix molding is opaque and tends to have glass patterns because it contains glass I fibers, and there are physical problems with hot water resistance and heat resistance. was there.

The present invention aims to improve the current state of the art, and provides an artificial marble that is excellent in hot water resistance, heat resistant, and flame retardant.

(Means and effects for solving the problem) As a result of various studies conducted by the present inventors, it was found that artificial marble obtained by dispersing a specific amount of a specific filler into a specific marble body and then molding and hardening it is well-produced. The present invention has been completed by discovering that the object can be achieved.

That is, the present invention provides a monomer mixture 10 containing an aliphatic polyfunctional (meth)acrylate and an aromatic vinyl compound as essential components.
0 parts by weight, 100 to 800 parts of metal oxide hydrate
This invention relates to heat-resistant and hot water-resistant artificial marble obtained by dispersing parts by weight and then molding and hardening.

Depending on the method of mixing and dispersing the hydrated gold fi oxide, this single matrix mixture can be made into a casting compound with a high filler content and low viscosity, and also has excellent fluidity when pressurized. It can also be used as a molding material for fresh bread.

In other words, if mixed using a mixer capable of high-speed stirring such as a disper or a homomixer, thixotropy will temporarily occur during mixing, resulting in almost no fluidity, but eventually the monomer will Even if a large amount of 300 parts by weight or more of the metal oxide hydrate is added to 100 parts by weight of the mixed liquid, a low-viscosity compound with 10 to 100 voids suitable for casting can be obtained.

In addition, if mixed using a low-speed mixer such as a kneader, as the metal oxide hydrate is added, it will become a sticky lump like bread, and while maintaining its shape, the metal oxide will eventually be mixed. Even if a large amount of oxide hydrate is added, up to about 800 parts by weight, it can be mixed, and a dough-like molding material with excellent fluidity when pressurized can be obtained. The low-viscosity compound or raw bread-like molding material obtained in this way can be easily cast or molded under heat and pressure, and especially when the amount of filler is about 250 to 400 parts by weight, it has a beautiful translucent, milky white color. You can obtain artificial marble.

Also, at a high filler content of 400 to 800 iiffi parts, a milky white artificial marble with a high degree of flame retardancy is obtained. Moreover, this artificial marble product does not require a gel coat, and its appearance does not change even when immersed in boiling water for a long time.

The aliphatic polyfunctional (meth)acrylates used in the present invention include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, and neobentyl glycol di(meth)acrylate. , glycerin tri(meth)acrylate, trimethylolpropane tri(meth)
Acrylate, dipentaerythritol hexa(meth)
Contains acrylate, etc.

Examples of aromatic vinyl compounds include styrene, α-methylstyrene, p-methylstyrene, and divinylbenzene.

The ratio of aliphatic polyfunctional (meth)acrylate and aromatic vinyl compound may be 20 to 8.0 ffiffi% for the former and 80 to 20% by weight for the latter, but more preferably 30 to 70% by weight for the former and 80 to 70% by weight for the latter. It is 70-30% by weight. The above two types are essential components of the monomer mixture in the present invention, but a part of the monomer mixture also contains (meth)acrylic acid, salts thereof, methyl (meth)acrylate, and isobutyl (meth)acrylate.
It is also possible to use various (meth)acrylate monomers such as meth)acrylate, or other monomers and oligomers such as various macromonomers, unsaturated polyester oligomers, fumaric acid esters, and maleimides.

However, if these other monomers or oligomers are used extensively, it may be difficult to obtain a product with a high filler content, or the product may have poor heat resistance and hot water resistance. Furthermore, if the other monomers used have low boiling points, they may foam during molding and the product may become opaque. Furthermore, a thermoplastic polymer may be added to the monomer mixture in order to reduce shrinkage during molding and hardening, prevent cracks and improve surface smoothness of the product. Examples of thermoplastic polymers include (meth)acrylic polymers such as polymethyl methacrylate, (meth)acrylic-styrene copolymers, polystyrene, polyvinyl acetate, styrene-vinyl acetate copolymers, polyvinyl chloride, polybutadiene, and polyethylene. Conventionally known low-shrinkage polymers such as , polycaprolactam, and saturated polyester can be used alone or in combination.

When multiple thermoplastic polymers for low shrinkage are blended,
This may lead to an increase in the viscosity of the monomer mixture, making it difficult to obtain a casting compound with a high filler content, or resulting in a product with poor transparency and heat resistance. Therefore, it is best to use as little as possible of the thermoplastic polymer for low shrinkage, and use it in an amount of 40 parts by weight or less, more preferably 5 to 30 parts by weight, per 100 parts by weight of the monomer mixture. is desirable.

Further, a thickening polymer can also be used for the purpose of increasing the viscosity during molding and further improving handling workability for press molding. Examples of this thickening polymer include methacrylate-based polymers obtained by copolymerizing methyl methacrylate with 1 to 2 percent (meth)acrylic acid, and maleated isoprene rubber, which have two carboxyl groups on the side chains or terminals. Thermoplastic polymers with two or more hydroxyl groups in one molecule, such as methacrylate polymers obtained by copolymerizing methyl methacrylate with 1 to 2% by weight of hydroxyethyl methacrylate, and polypropylene glycol. There are plastic polymers. As thickeners for these two types of thickening polymers, metal oxides and hydroxides such as magnesium oxide and magnesium hydroxide are used for the former, and polyfunctional hydroxides such as tolylene diisocyanate and isophorone diisocyanate are used for the latter. Isocyanates are used.

Hydrates of metal oxides used in the present invention include, for example, aluminum hydroxide, magnesium hydroxide, and calcium hydroxide. Among these, it is preferable to use a hydrated metal oxide having an average particle size of 5 microns or less, as this results in a beautiful product with particularly good surface condition and particularly excellent hot water resistance.

Furthermore, those with white discoloration of 90% or more are particularly preferable.

In this case as well, the amount of water in the gold fl oxide is within the range that does not adversely affect the flame retardancy of products from which inorganic fillers such as silica, alumina, quartz, calcium silicate, calcium carbonate, talc, and clay can be obtained. It can be used in place of a part of Japanese products.

It is preferable to use a silane coupling agent when dispersing the monomer mixture and the metal oxide hydrate, since this improves the water resistance of the product obtained by molding and curing. Examples of the silane coupling agent include γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriethoxysilane, and vinyltriacetoxysilane.

Examples of curing agents used in molding and curing include benzoyl peroxide, cyclohexanone peroxide, methyl ethyl ketone peroxide, bis(4-
t-butylcyclohexyl) peroxydicarbonate, t-butylperoxydibenzoate, t-butylperoxyoctoate, etc. are used. Among these, particularly preferred for press molding are medium- and high-temperature curing agents such as t-butyl peroxyoctoate and benzoyl peroxide, which give cured products with good transparency without causing cranking. In addition, medium- to low-temperature curing agents can be used alone or together with organic amines or polyvalent metal salts as accelerators, but bis(4-t-butylcyclohexyl) peroxydicarbonate (4-t-butylcyclohexyl) is particularly preferred for casting purposes. Barikidox PX-16, manufactured by Nippon Herbal Medicine.

In order to specifically carry out the present invention, for example, 80 to 20% by weight of aliphatic polyfunctional (meth)acrylate, preferably 70 to 30% by weight, and 20 to 80% by weight, preferably 30 to 70% by weight of aromatic vinyl compound. % by weight of a monomer mixture is prepared, and 100 to 800 parts by weight of a metal oxide hydrate is dispersed in 100 parts by weight of this mixture. At this time, the gold i oxide hydrate may be treated with a silane coupling agent in advance, or the amount may be 0.1 to 2.0% based on the weight of the metal oxide hydrate used. By dissolving or dispersing a corresponding silane coupling agent in the monomer mixture and then using the metal oxide aqueous phase, the water resistance of the resulting product can be improved.

In addition to the metal oxide hydrate added to the monomer mixture,
If necessary, various fillers, glass, etc., in ranges and amounts that do not negate the effects of the present invention! ! Reinforcement of fibers, etc. $11I [, mold release agents such as zinc stearate, thixotropic agents, plasticizers, flame retardants and flame retardants,
Coloring agents and the like may also be added. Further, the curing agent is usually added in an amount corresponding to 0.5 to 3.0% based on the weight of the monomer mixture.

As for the dispersion method, a high-speed stirrer, a pigment dispersion machine for paint production, or a mixed wire roll can be used to prepare a low-viscosity compound for casting, and a raw bread-like molding material for press molding can be used. To achieve this, a low-speed, powerful mixer such as a kneader is suitable.

The low-viscosity compound or molding material thus obtained is injected, press-fitted, or put into a mold, and molded and hardened by various molding methods such as casting, pressing, injection, extrusion, and transfer. In the case of cast molding, preliminary curing is performed at a temperature of, for example, about 60°C, and if necessary, post-curing is performed by heating at 80 to 120°C to obtain a product. In the case of hot pressure molding using a press, the product can be cured at a mold temperature of, for example, 80 to 180°C.

(Effects of the invention) The artificial marble of the present invention is flame retardant, does not change in appearance such as whitening even when immersed in boiling water for a long time, has a high heat distortion temperature, and has been tested in tobacco resistance tests and other contamination tests. It is a beautiful product that gives excellent results even in applications such as bathtubs and kitchen counters, and can be safely used in areas where it has traditionally been difficult to use due to lack of heat resistance and hot water resistance.

Examples will be described in more detail below, but these do not represent the entirety of the present invention.

Example 1 50 parts by weight of trimethylolpropane trimethacrylate, 50 parts by weight of styrene and a silane coupling agent (K
BM-503, manufactured by Shin-Etsu Chemical ■] 0.5-heavy part was mixed,
A monomer mixture was prepared. Next, 300 parts by weight of aluminum hydroxide (Hisilite H-320, average particle size 3.5 microns, manufactured by Showa Light Metal) was kneaded into this mixed solution using a high-speed stirrer, and then a curing agent bar force dox was added. PX-16
(Bis(4-t-butylcyclohexyl) peroxydicarbonate, manufactured by Nippon Kayaku ■) 0.8 parts was added, and after mixing, foaming was carried out under reduced pressure to obtain a blend. The viscosity of this blend was:
There were 19 voices at a liquid temperature of 30°C.

Next, this formulation was poured into a 200 x 150 x 6 m+ casting mold, cured at 45°C, cured in 55 minutes, and further post-cured at 120°C for 2 hours. The cured product is milky white and beautifully scatters light, with an astronomical stone-like translucency, is flame retardant, and as shown in Table 1, has a high heat distortion temperature and excellent stain resistance. It was a plate-like object.

Example 2 40!1 parts of trimethylolpropane trimethacrylate, 30 parts by weight of styrene and silane coupling agent (K
BM-503, manufactured by Shin-Etsu Chemical ■ Mix 0 and 5-layer parts,
A monomer mixture was prepared. Next, 300 parts by weight of aluminum hydroxide (Hisilite H-320, average particle size 3.5 microns, manufactured by Showa Light Metal) was kneaded into this mixed solution using a high-speed stirrer, and then a hardening agent was added to the bar. PX-16
0.8 parts by weight of (bis(4-t-butylcyclohexyl) peroxydicarbonate, manufactured by Nippon Koyaku ■) was added, mixed and defoamed under reduced pressure to obtain a blend.The viscosity of this blend was:
The liquid was 23 voices at 130°C.

Next, this mixture was poured into a 200x150x6JII casting mold and cured at 45°C, cured in 50 minutes, and further post-cured at 120°C for 2 hours. The cured product is milky white and beautifully scatters light, with an astronomical stone-like translucency, is flame retardant, and as shown in Table 1, has a high heat distortion temperature and excellent stain resistance. It was a plate-like object.

Implementation flA3 50 parts by weight of trimethylolpropane trimethacrylate, 50 parts by weight of styrene and silane coupling agent (K
BM-503, manufactured by Shin-Etsu Chemical ■] 0.5 parts by weight were mixed,
A monomer mixture was prepared. Next, 400 parts by weight of aluminum hydroxide [Hisilite H-310, average particle size 17 microns, manufactured by Showa Light Metal ■] was kneaded into this mixed solution using a high-speed stirrer, and then the curing agent Bariki Dox PX- 16(
0.8 fiffi part of bis(4-t-butylcyclohexyl) peroxydicarbonate (manufactured by Nippon Kayaku ■) was added, and after mixing, defoaming was carried out under reduced pressure to obtain a blend. The viscosity of this formulation was 25 voices at 130°C.

Next, this formulation was poured into a casting mold measuring 200 x 150 x 6 m and cured at 45°C, cured in 50 minutes, and further post-cured at 120°C for 2 hours. The cured product is milky white and beautifully scatters light, with an astronomical stone-like translucency, is flammable, and as shown in Table 1, has a high heat distortion temperature and excellent stain resistance. It was a plate-like object.

Example 4 40!1 parts of trimethylolpropane trimethacrylate, 40 m parts of styrene, and 20 parts by weight of isobutyl methacrylate were mixed to prepare a monomer mixture. Next, aluminum hydroxide [Hisilite H-320S] was added to this mixed solution.
T, average particle size 3.0 microns, manufactured by Showa Light Metal ■ 400
Parts by weight were kneaded using a high-speed stirrer, and then 0.8 parts by weight of Bariki Dox PX-16 (bis(4-t-butylcyclohexyl) peroxydicarbonate, manufactured by Nippon Herbal Pharmaceutical Co., Ltd., manufactured by Tama) was added. In addition, after mixing, degassing was carried out under reduced pressure to obtain a blend.The viscosity of this blend was 33 voices at a liquid temperature of 30°C.Next, this blend was poured into a casting mold of 20Q x 150 x 6m+, 45 when cured at 45℃
It was cured within minutes and was further post-cured at 120° C. for 2 hours. The cured product is milky white and beautifully scatters light, with an astronomical stone-like translucency, is flame retardant, and as shown in Table 1, has a high heat distortion temperature and excellent stain resistance. It was a plate-like object.

Example 5 40 parts by weight of dipentaerythritol hexamethacrylate, 60 parts of styrene and a silane coupling agent (
KBM-503 (manufactured by Shin-Etsu Chemical @J) 0 and 5 weight portions were mixed to form a monomer mixture. Next, 300 parts of aluminum hydroxide [Hisilite H-320, average particle size 3.5 microns, manufactured by Showa Light Metal ■] was kneaded into this mixed solution using a high-speed stirrer, and then the bar force of the curing agent was mixed. Dox PX-
16 (bis(4-t-butylcyclohexyl) peroxydicarbonate, Japanese Herbal Medicine ■'I) 0.8 parts were added, and the mixture was foamed under reduced pressure to obtain a blend. The viscosity of this formulation was 67 voices at a liquid temperature of 30°C.

Next, this formulation was poured into a 200x150x6s casting mold and cured at 45°C for 40 minutes, followed by post-curing at 120°C for 2 hours. The cured product is milky white and beautifully scatters light, has an astronomical stone-like translucency, is flame retardant, and as shown in Table 1,
The plate-like material had a high heat distortion temperature and excellent stain resistance.

Example 6 30 parts by weight of trimethylolpropane trimethacrylate, 70 parts by weight of styrene, silane coupling agent (KBM
-503, manufactured by Shin-Etsu Chemical ■] 0.5 Heavy Ichibe and t-butyl peroxyoctoate (barbutyl 01 NOF ■
0.5 overlapping parts were mixed to form a monomer mixture. next,
Aluminum hydroxide (Hisilite H-3
20, average particle size 3.5 microns, manufactured by Showa Light Metal ■30
0 parts by weight and 3 parts of zinc stearate were kneaded using a kneader to obtain a molding material in the form of fresh bread. The viscosity of this molding material was measured at 30°C using a B-type helipath rotational viscometer: 42. It was OOO Boys. Next, this molding material was put into a press molding mold of 200 x 200 x 6 m, and 1
It was cured at 100° C. in 8 minutes at 9 parts cm 2 in 30°C. The obtained molded product is milky white and has an astronomical stone-like translucency that scatters light beautifully, is flame retardant, and has a high heat distortion temperature as shown in Table 1.
The plate-like material also had excellent stain resistance.

Examples 7 to 9 Molding materials were obtained by kneading in the same manner as in Example 6 using the formulations shown in Table 1. Each of the obtained molding materials was cured in the same manner as in Example 6 to obtain an astronomical stone-like molded product. The performance of each molded product is shown in Table 1. The molded products obtained in Examples 7 and 8 were milky white and semitransparent, and the molded products obtained in Example 9 were white and semitransparent to opaque.

Comparative Example 1 Polymethyl methacrylate [Acrivet MD001,
27 parts by weight of Mitsubishi Rayon ■ were dissolved in 73 parts by weight of methyl methacrylate to obtain a methyl methacrylate silica with a viscosity of 5 voids.

Next, aluminum hydroxide [Hisilite H-310, average particle size 17 microns, Showa Light Metal FF (
200 parts by weight of rear packaging) were kneaded using a high-speed stirrer, and then hardening agent VARCADOX PX-16 [Nippon Kayaku @J
0.8 part by weight was added thereto, and after mixing, defoaming was carried out under reduced pressure to obtain a resin blend. The viscosity of this resin compound is 23 at a liquid temperature of 30°C.
It was difficult to cast molds because it had zero voice, had many residual bubbles, and had poor fluidity. 20% of this resin formulation
When poured into a casting mold of 0 x 150 x 6 m and cured at 45°C, it hardened in 50 minutes, and then heated at 110°C for 2
Post-cured for an hour. As shown in Table 1, the physical properties of the obtained cured product had problems in heat resistance and hot water resistance.

Comparative Example 2 Silane coupling agent (KB
M-503, made by Shin-Etsu Chemical @) in a resin solution mixed with 0.5 parts by weight of aluminum hydroxide
0, average particle size 17 microns, manufactured by Showa Light Metal ffl@I) 2
00 parts by weight were kneaded using a high-speed stirrer, and then the curing agent Berkat')'), PX-16 (Nippon Kai1j
Add 0.8 parts of ffi (manufactured by wJ) and reduce the pressure to 11Q after mixing.
A resin formulation was obtained by foaming.

The viscosity of this resin compound was 180 voices at liquid g3o'c, with a lot of residual air bubbles and poor fluidity.
Casting was difficult. This resin compound is 200X15
When poured into a 0x6m+ casting mold and cured at 45°C, it cured in 60 minutes, and then at 110°C for 2 hours.
Post-cured. As shown in Table 1, the physical properties of the obtained cured product had problems in heat resistance and hot water resistance.

Claims (1)

[Claims] 1. 100 to 800 parts by weight of a metal oxide hydrate per 100 parts by weight of a monomer mixture containing an aliphatic polyfunctional (meth)acrylate and an aromatic vinyl compound as essential components. Heat-resistant and hot water-resistant artificial marble made by dispersing and then molding and hardening. 2. The heat-resistant and water-resistant artificial marble according to claim 1, wherein the average particle size of the metal oxide hydrate is 5 microns or less.