JPH07300940A - Manufacture of noncombustible artificial marble - Google Patents

Abstract

PURPOSE:To provide an excellent fire protecting performance by mixing a polymerized monomer with an inorganic material consisting of natural crushed stone and aluminum hydroxide, and by forming and hardening it to form a noncombustible artifical marble. CONSTITUTION:The mean grain diameters of an inorganic material are devided into four grain diameter groups: coarse grains A of 50 to 300mm, intermediate grains B of 2 to 6mm, fine grains C of 0.04 to 0.10mm, and minute grains D of 0.005 to 0.015wt.%. These grain diameter groups are mixed in the mixing ratio of the coarse grains A 50 to 70wt.%, intermediate grains B 20 to 30wt.%, fine grains C 5 to 15wt.%, and minute grains D 1 to 10wt.%. Further, the polymerized monomer with regard to the total weight 100 parts by weight of the inorganic material is mixed as much 0.5 to 10 parts by weight than the target value of 2 to 5 parts by weight. Then, in order to closely compact the filled material after filling it into a form, the vacuum suction of -10 to -30mmHg, vibration of 60 to 120Hz and 0.5 to 2mm amplitude, and pressurization of 10 to 100kgf/cm<2> are applied to the material so as to be formed. Thus, the manufacturing cost can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-combustible artificial marble useful in the construction industry as a substitute for natural stone.

[0002]

2. Description of the Related Art Natural stone is a non-combustible material and has a high decorative value, and it is used in building materials such as flooring and wall materials and in various other fields, but it is not possible to obtain thin or large products. Artificial marble is used instead of natural stone because some types produce very little and are expensive. The following are examples of conventional artificial marble technology.

That is, the one made of a methyl methacrylate polymer and alumina hydrate found in Japanese Examined Patent Publication No. 50-22586, and the one made of an acrylic resin syrup and fine powder of kaolin found in Japanese Examined Patent Publication No. 3-71442. , A thermosetting resin found in JP-A-3-150244, a fine powder filler, a natural crushed stone and other components, and an aliphatic polyfunctional (meth) acrylate and an aromatic vinyl compound as essential components. A heat-resistant and heat-resistant water-curable composition comprising 100 to 800 parts by weight of an inorganic filler having an average particle size of 5 microns or less in 100 parts by weight of a monomer mixture (JP-A-62-199640). A method for producing an artificial marble characterized by adding an inorganic filler and a vinyl group-containing silane to a polymerization raw material, and then polymerizing and curing the same (JP-A-3-4554). JP), polymethacrylimide 5-50 wt%, cross-linked polymer composed mainly of methyl methacrylate or styrene 95-50 wt%
An artificial marble (JP-A-3-174346) comprising 70 to 20% by weight of a thermoplastic resin (A) and 30 to 80% by weight of an inorganic filler (B). The above-mentioned technique relates to artificial marble containing an inorganic material and a synthetic resin, and the artificial marble containing such an inorganic material and a synthetic resin is widely used as a building material or an interior decoration. However, since they have a large amount of synthetic resin in the artificial marble, they have drawbacks in heat resistance and combustion resistance and cannot be used as interior wall materials, thus limiting their applications.

[0004]

In view of the above situation, the present inventor has researched a method for producing a product having high heat resistance and high combustion resistance while containing a synthetic resin and having favorable properties as an artificial marble. The invention has been earnestly achieved.

That is, the object of the present invention is to obtain a feel and transparency equivalent to that of natural stone by containing the synthetic resin while having high heat resistance and combustion resistance while containing the synthetic resin, and at the same time, as an artificial stone. It is intended to provide a method for producing a non-combustible artificial marble that has strength, water resistance, weather resistance, etc. that can be used and can be used not only as an interior wall material in a structure that should use a non-combustible material but also as a floor material. .

[0006] Another object of the present invention is to provide a method for producing artificial marble which solves the above problems based on the particle size blending so that the inorganic material contained in the artificial marble has a minimum porosity.

[0007]

The gist of the present invention is (1)
Average particle size (A) 50-300 mm, (B) 2-6 m
m, (C) 0.04 to 0.10 mm, (D) 0.005
An inorganic material having a particle size group of ˜0.015 mm has a compounding ratio (wt%) of (A) 50 to 70, (B) 20 to 3
0, (C) 5 to 15 and (D) 1 to 10, and 2 to 5 parts by weight of a polymerizable monomer to 100 parts by weight of the total weight of the inorganic material. The method of manufacturing non-combustible artificial marble, which is molded and hardened after compounding regardless of the order of

(2) The non-combustible material according to (1) above, wherein the particle size groups (A) and (B) are natural crushed stones, and the particle size groups (C) and (D) are aluminum hydroxide. Manufacturing method of artificial marble,

(3) A predetermined amount of particle size group (A) is cast, and then a predetermined amount of particle size group (B), particle size group (C) and particle size group (D) is dry-mixed, A mixture of a predetermined amount of a polymerizable monomer and a polymerization catalyst or a polymerization initiator is added to the mixture and then mixed to obtain a particle size group (B), a particle size group (C), a particle size group (D) and a polymerization. A method for producing a non-combustible artificial marble according to the above (1) or (2), which comprises producing a mixture of a polymerizable monomer, casting the mixture, and integrating the mixture with the particle size group (A).

(4) The polymerizable monomer is added in an amount of 0.5 to 10 parts by weight more than the target value based on 100 parts by weight of the total weight of the inorganic material, and the mixture is dispersed while volatilizing until reaching the target value, and dispersed. And manufacturing the non-combustible artificial marble according to (1), (2) or (3),

(5) The polymerizable monomer is uniformly dispersed in the inorganic material, and after casting, vacuum suction of -10 to -30 mmHg and 6
Vibration of 0 to 120 Hz, amplitude of 0.5 to 2 mm and 10
The method for producing a non-combustible artificial marble according to the above (1), (2), (3) or (4), which comprises simultaneously applying a pressure of -100 kgf / cm ² and molding.

[0012] A further preferred method for producing the non-combustible artificial marble of the present invention is (6) the non-combustible artificial marble described in the above (1) to (5), which has a non-combustible degree of 50 ° C or less, more preferably 30 ° C or less. Is a manufacturing method of.

Next, the present invention will be described in detail. The polymerizable monomer used in the present invention is a general term for raw materials for producing a thermosetting resin or a thermoplastic resin. Examples of such a polymerizable monomer include maleic acid, fumaric acid, ethylene glycol, diethylene glycol and styrene, or partial polymers thereof, which produce an unsaturated polyester resin of a thermosetting resin. Epichlorohydrin, polyhydric phenols, amines, organic acids and acid anhydrides that form epoxy resins, or partial polymers thereof, or methyl methacrylate and other monomers that form thermoplastic resins, and partial polymers thereof Alternatively, it is a mixture thereof. The polymerizable monomer is methyl methacrylate (hereinafter referred to as MM because of its weather resistance, transparency, hardness and thermal characteristics).
Sometimes expressed as A. ), Their partial polymers, mixtures thereof and unsaturated polyesters. If necessary, a mixture of styrene with methyl methacrylate and methyl methacrylate with an unsaturated polyester may be used.

A radical polymerization initiator such as an organic peroxide or an azo compound is used as a polymerization initiator for the polymerizable monomer, and the amount thereof is 0.005-1 with respect to the polymerizable monomer.
% By weight, preferably 0.02-0.2% by weight
Added. Specific examples of the organic peroxide used as the radical polymerization initiator include bis (4-t-butylcyclohexyl) peroxydicarbonate, t-butylperoxypiperate, t-hexylperoxypiperate, t-butyl. Peroxy neohexanoate, t-hexyl peroxy neohexanoate, benzoyl peroxide, etc. can be mentioned, and the azo compound is 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile). , 2,2′-azobis (2,4-dimethylvaleronitrile), azobisisobutyronitrile and the like. Further, the mixture of the polymerizable monomer and the polymerization initiator includes a promoter such as cobalt naphthenate and cobalt octoate, silane coupling such as γ-methacryloxypropyltrimethoxysilane and γ-glycidoxylopyrtrimethoxysilane. Agents, internal mold release agents such as zinc stearate, and other general additives may be used alone or in combination within a range that does not impair the object of the present invention.

Examples of the inorganic material used in the present invention include natural crushed stone, glass powder, aluminum hydroxide, calcium aluminate hydrate, magnesium hydroxide, calcium aluminate, calcium hydroxide, silica, alumina powder and talc. To be Natural crushed stone refers to crushed rock of andesite, granite and other igneous rocks, serpentine, metamorphic rock such as crystalline limestone, sandstone, slate, limestone and other sedimentary rocks, which can be used alone or in combination of two or more kinds . If necessary, an inorganic pigment such as iron oxide or cobalt oxide can be added.

In the present invention, in order to improve the incombustibility of the artificial marble, the content of the polymerizable monomer needs to be 2 to 5 parts by weight with respect to 100 parts by weight of the inorganic material. Therefore, the inorganic material used in the present invention is blended with a particle size such that the porosity is minimized. The particle size composition is such that the average particle size is (A) 50 to 300 m.
m, (B) 2 to 6 mm, (C) 0.04 to 0.10 mm
And (D) the blending ratio (% by weight) of the inorganic material consisting of the particle size group of 0.005 to 0.015 mm is (A) 50 to
70, (B) 20 to 30, (C) 5 to 15 and (D)
More preferably, the particle size group (A) and the particle size group (B) are natural crushed stones, and the particle size group (C) and the particle size group (D) are aluminum hydroxide. Inorganic materials having a particle size of 0.001 mm or less, such as titanium oxide and silica fume, have poor dispersibility and are difficult to fill, which is not preferable.

In order to produce the non-combustible artificial marble of the present invention, among the above-mentioned inorganic materials, first, a particle size group (B) (hereinafter sometimes referred to as an intermediate particle (B)) and a particle size group (C). ) (Hereinafter sometimes referred to as fine particles (C)) and a particle size group (D) (hereinafter sometimes referred to as fine particles (D)) are dry-mixed, and the mixture is placed in the mixture. After adding a fixed amount of a mixture of a polymerizable monomer and a polymerization catalyst or a polymerization initiator, the mixture is mixed using a biaxial defoaming decompression type universal mixer to obtain intermediate particles (B), fine particles (C) and fine particles. A mixture of (D) and the polymerizable monomer is produced. Next, a predetermined amount of particle size group (A) (hereinafter sometimes referred to as coarse particles (A)) is filled in the mold, and the mixture of the four particles is further filled. After that, it is densified by vacuum suction, vibration, and pressure, and 60 to 120 ° C.
Cure for 1 hour to 1 week.

In the present invention, the content of the polymerizable monomer is about 2 to 5% by weight of the product, which is an extremely small amount as compared with the conventional artificial marble. Therefore, the polymerizable monomer is uniformly dispersed in the inorganic material. It is important to let Therefore, the polymerizable monomer is added to the target value of 2 to 5 with respect to 100 parts by weight of the total weight of the inorganic material.
By mixing 0.5 to 10 parts by weight more than parts by weight and mixing while volatilizing until reaching the target value, granules with a high content of polymerizable monomer are not generated partially, and the whole inorganic material is easy Can be uniformly dispersed. If the amount added is less than the target value of 0.5 parts by weight, a sufficient effect of preventing the generation of granules cannot be obtained. In addition, the amount of increase in the blended amount is 1 of the target value.
If it exceeds 0 parts by weight, the time required for volatilization to reach the target value becomes long and the production efficiency deteriorates.

In order to densify the filling material after casting, vacuum suction of -10 to -30 mmHg and 60 to 120 are performed.
Hz, vibration with an amplitude of 0.5-2 mm and 10-100 k
It is preferable to apply a pressure of gf / cm ² at the same time, but vacuum suction can be omitted. In order to prevent the polymerizable monomer from volatilizing from the filling through the gap between the molds during heating and curing, resulting in non-uniform resin concentration in the cured product, it is better to seal the gap between the molds with a silicone sealant or the like. preferable. Among the above-mentioned manufacturing methods, the polymerizable monomer that volatilizes during mixing, casting and curing can be recovered and reused by a recovery device such as a trap. The artificial marble molded article obtained by the present invention is subjected to finishing such as cutting and polishing, if necessary, and then used as a substitute for natural stone in the field of construction industry and other applications.

The fireproof performance test in the following examples and comparative examples is carried out in accordance with the provisions of the base material test and surface test in Ministry of Construction Notification No. 1828 of 1945. In the base material test, use a heating furnace that can stabilize the thermocouple from 740 ° C to 760 ° C for 30 minutes or more. When the test piece is inserted and heated for 20 minutes, the temperature indicated by the thermocouple and 750 ° C are not combustible. Determine sex. That is, in this specification, the difference between the temperature indicated by the thermocouple and 750 ° C. when the test body is inserted and heated for 20 minutes is defined as the incombustibility.

In the present invention, artificial marble having a nonflammability of 50 ° C. or less can be suitably obtained by using the above-mentioned manufacturing method, but the preferred artificial marble has a nonflammability of 30 ° C. or less. When the incombustibility exceeds 50 ° C, there are cases where defects occur as a substitute for natural marble.

The surface test is conducted by the Ministry of Construction No. 18 of 1945.
It is done according to the regulation of No. 28. The surface test is judged by whether the test specimen meets the conditions of the following items. (1) No harmful deformation for fire prevention or generation of gas that is extremely harmful for evacuation. (2) There is no melting of the test body over the entire thickness or cracks reaching the surface of the test body, and the width of the crack on the back surface is 1/10 or more of the plate thickness of the total thickness. (3) There is no afterflame for 30 seconds or more after heating is completed. (4) The exhaust temperature curve of the test piece should not exceed the exhaust temperature curve of the standard plate that was autoclaved with the asbestos perlite plate. (5) The smoke emission coefficient CA per unit area obtained by the following formula is 30 or less.

[0023]

[Equation 1] CA = 240 log X / Y

In this equation, X and Y represent the following numerical values, respectively. X: Light intensity at the start of heating test (unit: lux) Y: Minimum value of light intensity during heating test (unit: lux)

[0025]

【Example】

Example 1 Polymerizable monomer obtained by adding 0.05 parts by weight of bis (4-t-butylcyclohexyl) peroxydicarbonate to 100 parts by weight of methyl methacrylate 4 parts by weight Marble having an average particle size of 100 mm 54 parts by weight Average Marble with a particle size of 4 mm 24 parts by weight Aluminum hydroxide with an average particle size of 0.09 mm (Sumitomo Chemical Co., Ltd., trade name CW375, the same below) 14 parts by weight Aluminum hydroxide with an average particle size of 0.009 mm (Sumitomo Chemical Industry Co., Ltd., trade name CW308, the same applies hereinafter.) 5 parts by weight Of the above components, the amount of each of the components except the marble having an average particle size of 100 mm except for the marble is measured using a biaxial defoaming decompression universal mixer. Was mixed until it became 3 parts by weight. Then average particle size 10
Pour this mixture into a mold that is pre-filled with 0 mm marble, vacuum suction at -20 mm Hg and 120 H.
z, vibration of 1 mm, pressure of 10 Kgf / cm ² were simultaneously applied to densify the filling, and the gap between the molds was sealed with a silicone sealant, followed by heating at 80 ° C. for 15 hours and further 12
A molded product was obtained by heating at 0 ° C. for 5 hours. 220mm × 220mm × 10mm and 40m from the obtained artificial marble
Cut out a test piece measuring mx 40 mm x 50 mm,
In accordance with the regulations of Ministry of Construction Notification No. 1828, the surface test and the base material test of the fireproof performance test were performed. As a result, in the front surface test, there was no melting over the entire thickness and in the back surface, there was no crack reaching the back surface, and in the base material test, the temperature rise in the furnace, that is, the incombustibility was 23 ° C., and good fire protection performance specified by the Building Standards Law was exhibited. The compounding ratios of the inorganic materials and the test results are shown in Tables 1 and 2. The heating test result of the surface test is shown in FIG.

[0026]

[Table 1]

[0027]

[Table 2]

Example 2 Among the inorganic materials of Example 1, marble having an average particle size of 100 mm was replaced with granite having an average particle size of 80 mm, and the mixture was mixed, filled and heated in the same manner as in Example 1 to obtain the obtained molding. Cutting the goods,
Polished. The resulting product was a granite-like marble with no cracks or warpage. In addition, when a fireproof performance test was conducted on this product, it passed both the surface test and the base material test, and the temperature rise in the furnace, that is, the incombustibility was 38 ° C., showing good fireproof performance specified by the Building Standards Act. The compounding ratios of the inorganic materials and the test results are shown in Tables 1 and 2.

Comparative Example 1 Polymerizable monomer similar to that in Example 1 5 parts by weight Marble having an average particle size of 25 mm 55 parts by weight Glass chips having an average particle size of 1 mm 32 parts by weight Aluminum hydroxide having an average particle size of 0.09 mm 7 Parts by weight 2 parts by weight of titanium oxide having an average particle size of 0.0005 mm All the above components are mixed until the amount of the polymerizable monomer is 4 parts by weight in the same manner as in Example 1, and the same method as in Example 1 is performed. After filling, it was heated at 80 ° C. for 12 hours to obtain a molded product. The obtained molded product had poor titanium oxide dispersion and poor texture. Also, when a fireproof performance test was conducted, the surface test passed, but in the base material test, the temperature rise in the furnace, that is, the incombustibility was 83 ° C, which is a value for building materials with noncombustibility specified in the Building Standards Act. I couldn't say. The compounding ratios of the inorganic materials and the test results are shown in Tables 1 and 2.

Comparative Example 2 Polymerizable monomer similar to that of Example 1 6 parts by weight Marble having an average particle size of 12 mm 54 parts by weight Marble having an average particle size of 2 mm 21 parts by weight Marble having an average particle size of 0.4 mm 11 parts by weight Average 6 parts by weight of aluminum hydroxide having a particle size of 0.09 mm 2 parts by weight of aluminum hydroxide having an average particle size of 0.009 mm After all the above components were mixed for 1 minute without defoaming and decompressing with a biaxial defoaming universal mixer Then, the molded product was obtained by heating at 80 ° C. for 12 hours. The amount of monomer volatilization at the time of mixing this molded product was 0.05 parts by weight. When a fireproof performance test was conducted on the obtained molded product, the surface test passed, but in the base material test, the temperature rise in the furnace, that is, the incombustibility was 120 ° C., and the test failed. The compounding ratios of the inorganic materials and the test results are shown in Tables 1 and 2.

[0031]

EFFECTS OF THE INVENTION According to the present invention, a large amount of artificial marble having the same luster, color tone, and other textures as natural stone and having excellent fire protection performance, which is certified as a non-combustible material prescribed by the Building Standards Law, is manufactured. Therefore, it is possible to reduce the manufacturing cost. Among the present invention, those manufactured using an acrylic resin have excellent weather resistance and can prevent yellowing due to ultraviolet rays.

[Brief description of drawings]

FIG. 1 is a process drawing showing one embodiment of a method for producing a non-combustible artificial marble according to the present invention.

FIG. 2 shows results of surface test heating test of the artificial marble and the standard plate manufactured in Example 1.

Front page continuation (72) Inventor Shuji Fujimoto 1-12-32 Nishihonmachi, Ube City, Yamaguchi Prefecture Ube Head Office Ube Head Office

Claims (5)

[Claims] 1. An average particle size of (A) is 50 to 300 m.
m, (B) 2 to 6 mm, (C) 0.04 to 0.10 m
m, (D) an inorganic material having a particle size group of 0.005 to 0.015 mm and a compounding ratio (% by weight) of (A) 50 to 7
0, (B) 20-30, (C) 5-15 and (D) 1
10 to 10 and the total weight of inorganic material is 10
A method for producing an incombustible artificial marble, which comprises mixing 2 to 5 parts by weight of a polymerizable monomer with respect to 0 part by weight, regardless of the order in which the inorganic materials are mixed, and then molding and curing. 2. The noncombustible artificial marble according to claim 1, wherein the particle size groups (A) and (B) are natural crushed stones, and the particle size groups (C) and (D) are aluminum hydroxide. Manufacturing method. 3. A predetermined amount of particle size group (A) is cast,
Particle size group (B), particle size group (C) and particle size group (D)
Is dry-mixed with a predetermined amount, and a predetermined amount of a mixture of the polymerizable monomer and the polymerization catalyst or the polymerization initiator is added to the mixture, and then mixed to obtain a particle size group (B) and a particle size group (C). The method for producing an incombustible artificial marble according to claim 1 or 2, wherein a mixture of the particle size group (D) and the polymerizable monomer is produced, and the mixture is cast to be integrated with the particle size group (A). 4. A polymerizable monomer is added in an amount of 0.5 to 10 parts by weight more than a target value based on 100 parts by weight of the total weight of the inorganic material, and the mixture is dispersed while volatilizing until reaching the target value. The method for producing a non-combustible artificial marble according to claim 1, 2 or 3, which comprises molding. 5. A polymerizable monomer is uniformly dispersed in an inorganic material, and after casting, a vacuum suction of -10 to -30 mmHg and a vibration of 60 to 120 Hz and an amplitude of 0.5 to 2 mm and 1 are performed.
The method for producing an incombustible artificial marble according to claim 1, 2, 3 or 4, which comprises simultaneously applying a pressure of 0 to 100 kgf / cm ² and molding.