JP2001080944A - Production of artificial slate and artificial slate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably produce an artificial slate having uniform basic performance over the entire surface, excellent in designability and having high-grade appearance. SOLUTION: This artificial slate is produced through a kneading step in which a matrix material containing a matrix resin and a filler and granular natural stones are charged into a kneader to obtain a composition for the artificial slate and a molding step in which the composition is molded to obtain a platelike molding. The amount of the granular natural stones charged in the kneading step is 30-90 wt.% of the total amount of the matrix material and the granular natural stones, and the flow resistance of the composition used in the molding step is 0.5-5t.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing an artificial slab and an artificial slab.

[0002]

2. Description of the Related Art Artificial stone slabs are molded products in which a large number of granular natural stones are dispersed in a matrix, and have an appearance that can be easily recognized as high-grade natural stone slabs such as marble and granite. Have been. Unlike natural stone slabs, artificial slabs have the basic properties of excellent heat resistance, high strength such as compressive strength and bending strength, high impact resistance and surface hardness, low water absorption, and low scratch resistance. Boards, counters, vanities, walls,
It is suitably used for floors, partitions, and the like.

[0003] Such an artificial slab is prepared by kneading a matrix material containing a matrix resin and a filler with granular natural stone to obtain a composition for the artificial slab, and preforming the composition for the artificial slab. A molding step of charging the obtained artificial stone slab composition preform into a mold and molding, to obtain a plate-like molded article, and, if necessary, a surface polishing step of polishing the surface of this plate-like molded article Can be obtained.

Japanese Patent Application Laid-Open No. 3-150244 discloses that a compound containing a thermosetting resin, a filler, and a particulate natural stone of 20 mm or less has a curing catalyst, a low shrinkage agent,
An artificial stone sheet composition obtained by preforming an artificial stone sheet composition containing at least one kind of an additive consisting of a fiber reinforcing material and a thickener of 25 mm or less is molded and cured. The resulting artificial slab is disclosed. This artificial stone plate is a molded product in which a thermosetting resin, a low-shrinkage agent, a filler and the like are cured to form a matrix, in which granular natural stone is dispersed, and is used to mold a composition preformed product for the artificial stone plate. In this case, the viscosity of the composition for artificial stone slab was increased by using a thickener to improve the moldability, thereby obtaining the composition.

[0005] However, in the production of such artificial stone slabs, if there is a problem in kneading the granular natural stone and the matrix material, whitening occurs in the plate-like molded product obtained in the molding process, and nests, pinholes, cracks and the like occur. However, there is a problem that the ratio of defective products (defective rate) due to the occurrence of molding defects such as molding becomes high. In addition, when the amount of the used granular natural stone is increased in order to enhance the design property of the obtained artificial stone plate, there is a problem that the defective rate increases. In order to increase the commercial value of artificial stone slabs, it is necessary to enhance the design of the artificial slabs and improve the luxurious feeling. In such cases, it is necessary to keep the defect rate low and manufacture stably. Longed for.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has been developed to provide an artificial stone slab having uniform basic performance over the entire surface, excellent design, and high quality. It is an object of the present invention to provide a manufacturing method.

[0007]

According to the present invention, there is provided a kneading step in which a matrix material containing a matrix resin and a filler and granular natural stone are charged into a kneading machine to obtain a composition for an artificial slab.
A molding step of molding the composition for artificial stone plate to obtain a plate-like molded product, wherein the amount of the granular natural stone charged in the kneading step is a matrix material and a granular natural stone. 30 to 90 with respect to the total amount of
%, And the flow resistance value of the composition for artificial stone slab used in the molding step is 0.5 to 5 t (tons).
This is a method for producing an artificial stone slab.

The present invention also provides a kneading step in which a matrix material containing a matrix resin and a filler and granular natural stone are charged into a kneading machine to obtain a composition for an artificial slab, and the above-described composition for an artificial slab is formed. A molding step of obtaining a plate-like molded product by mixing, wherein the amount of the granulated natural stone charged in the kneading step is 30 to 90% by weight based on the total amount of the matrix material and the granulated natural stone. %, And the plate thickness [a (mm)] of the plate-like molded product obtained in the above-mentioned molding step is the maximum particle size [b of the granular natural stone.
(Mm)] and 0.3 <b / a <1. The present invention is also an artificial slab manufactured by the above-described method for manufacturing an artificial slab. Hereinafter, the present invention will be described in detail.

The method for producing an artificial slab according to the present invention comprises the steps of: kneading a matrix material containing a matrix resin and a filler and granular natural stone into a kneading machine to obtain a composition for the artificial slab; And a molding step of molding the composition to obtain a plate-like molded product.

The above-mentioned matrix material means a composition for forming a matrix of an artificial stone slab. The above-mentioned composition is kneaded with a particulate natural stone and then molded to form a matrix as described in detail below. Is what you do. The matrix material contains a matrix resin and a filler.

[0011] The matrix resin contains a thermosetting resin and, if necessary, a low-shrinking agent. The thermosetting resin is not particularly limited as long as it can be used as a molding material. Examples thereof include unsaturated polyester resins, vinyl ester resins (epoxy acrylate resins), (meth) acrylic syrups, diallyl phthalate resins, and the like. Radical polymerization type resins; epoxy resins, urea resins, melamine resins and the like. These may be used alone or in combination of two or more. Among these, unsaturated polyester resins are preferable because the basic performance such as the strength and surface hardness of the artificial stone plate is improved.

The unsaturated polyester resin is not particularly limited. For example, a polymer having a weight-average molecular weight (Mw) of several hundreds to several tens of thousands obtained by condensing an acid component and an alcohol component is converted to a vinyl monomer. Examples thereof include a radical polymerization type resin obtained by dissolution. The acid component is not particularly restricted but includes, for example, unsaturated dibasic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, mesaconic acid, citraconic acid, citraconic anhydride; phthalic acid, anhydride Phthalic acid, tetrahydrophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, halogenated phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, heptic acid, methyltetrahydrophthalic anhydride, endomethylenetetrahydro Saturated dibasic acids such as phthalic anhydride; and trifunctional or higher polybasic acids such as trimellitic acid, trimellitic anhydride, pyromellitic acid, and pyromellitic dianhydride. These may be used alone or in combination of two or more.

The alcohol component is not particularly restricted but includes, for example, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol,
Triethylene glycol, neopentyl glycol,
1,3-butanediol, 1,4-butanediol,
Glycols such as 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, propylene oxide adduct of bisphenol A, and ethylene oxide adduct of bisphenol A; trifunctional or higher alcohols such as glycerin, trimethylolpropane, and pentaerythritol; Epoxides such as ethylene oxide, propylene oxide, and epichlorohydrin are exemplified. These may be used alone or in combination of two or more.

The vinyl monomer is not particularly limited as long as it is a reactive monomer and can be cross-linked with the unsaturated group of the polymer at the time of molding. For example, styrene, α-methylstyrene, vinyltoluene, Chlorostyrene, vinyl acetate, allyl alcohol, ethylene glycol monoallyl ether, propylene glycol monoallyl ether, acrylonitrile, maleimides; unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, and unsaturated monocarboxylic acids thereof Monoesters of unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid and citraconic acid, and monoesters of these unsaturated dicarboxylic acids; ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene Glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate,
Polyfunctional (meth) acrylates such as trimethylolpropane tri (meth) acrylate and pentaerythritol tetra (meth) acrylate; divinylbenzene, diallyl phthalate, diallyl isophthalate, triallyl cyanurate, triallyl isocyanurate and the like. Further, for example, a (meth) acrylic polymer having an unsaturated group in a side chain, such as obtained by reacting a (meth) acrylic polymer having a carboxyl group with a glycidyl acrylate (meth) acrylate, or the like, may also be used. Can be used. These may be used alone or in combination of two or more.

The types and amounts of the acid component, the alcohol component, and the vinyl monomer in the unsaturated polyester resin are not particularly limited, and may be appropriately set according to the basic performance required for the artificial stone plate. Also,
The method for condensing the acid component and the alcohol component is not particularly limited, and for example, reaction conditions such as a reaction temperature and a reaction time may be appropriately set in the same manner as described above. The polymer may be modified with various components such as a diene compound such as dicyclopentadiene and a rubber component such as a terminal-functional butadiene-acrylonitrile copolymer.

The vinyl ester resin is not particularly limited. For example, radical polymerization obtained by dissolving a reaction product obtained by addition-polymerizing a vinyl unsaturated carboxylic acid at the terminal of an epoxy resin into a vinyl monomer is used. Mold resin and the like.

The epoxy resin is not particularly restricted but includes, for example, bisphenol type, novolak type, cycloaliphatic type and epoxidized polybutadiene type.

The vinyl unsaturated carboxylic acid is not particularly limited, and examples thereof include acrylic acid and methacrylic acid. The vinyl monomer is not particularly limited, and includes, for example, styrene, vinyl toluene, methyl methacrylate, vinyl acetate, chlorostyrene, diallyl phthalate, triallyl isocyanurate and the like.
These may be used alone or in combination of two or more.

The type and amount of the epoxy resin, the vinyl-based unsaturated carboxylic acid and the vinyl-based monomer in the vinyl ester resin are not particularly limited, and may be selected according to the basic performance required for the artificial stone board. What is necessary is just to set suitably. The method of addition polymerization of the epoxy resin and the vinyl unsaturated carboxylic acid is not particularly limited, and for example, reaction conditions such as a reaction temperature and a reaction time may be appropriately set in the same manner as described above.

The (meth) acrylic syrup is not particularly limited, and is, for example, a mixture containing a monomer (meth) acrylate, a polymer of (meth) acrylate, and a crosslinking agent. Yes, as needed
A radical polymerization type resin further containing the above-mentioned vinyl monomer is exemplified.

The above (meth) acrylate is not particularly restricted but includes, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate. , Lauryl (meth) acrylate, cyclohexyl (meth) acrylate, glycidyl (meth) acrylate and the like. Also,
(Meth) acrylamide can also be used. These may be used alone or in combination of two or more. Among them, methyl methacrylate or (meth) acrylic acid containing methyl methacrylate as a main component, since the basic properties such as weather resistance and surface gloss, appearance, and safety of the artificial stone plate can be further improved. Esters are preferred.

The polymer of the above (meth) acrylic ester can be obtained by polymerizing the above (meth) acrylic ester or, if necessary, a polymer containing a vinyl monomer as a monomer component. The polymerization degree of the (meth) acrylic acid ester polymer is not particularly limited.

The crosslinking agent is not particularly restricted but includes, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, neopentyl glycol. Multifunctional (meth) acrylates such as di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate; divinylbenzene, diallyl phthalate, diallyl isophthalate, triallyl cyanurate, triallyl isocyanurate And the like. These may be used alone or in combination of two or more.

The (meth) acrylic acid ester, the polymer of the (meth) acrylic acid ester, the crosslinking agent, and the kind and amount of the vinyl monomer used as required in the (meth) acrylic syrup are particularly There is no limitation, and it may be appropriately set according to the basic performance required for the artificial stone slab.

When the thermosetting resin contains two or more resins and forms a mixture, the content of each resin is not particularly limited. When a radically polymerizable resin is used as the thermosetting resin, a radically polymerizable resin other than the aforementioned radically polymerizable resin may be contained.

The low-shrinkage agent in the matrix resin is not particularly limited as long as it improves the dimensional stability of the obtained artificial stone plate. Examples thereof include polyethylene, polypropylene, polystyrene, three-dimensionally cross-linked polystyrene, and polymethacryl. Examples include methyl acid, polyethylene glycol, polypropylene glycol, cellulose butyrate, acetate (acetylcellulose), polyvinyl chloride, polyvinyl acetate, polycaprolactone, and saturated polyester. These may be used alone,
Two or more kinds may be used in combination. Among these, a saturated polyester is preferable.

The above matrix resin may further contain an additive, if necessary. The additives are not particularly limited, and include, for example, a curing agent, a thickener, an internal release agent, a coloring agent, a chain transfer agent, a polymerization inhibitor, an ultraviolet absorber, a thinner, a coupling agent, an antibacterial agent, and the like. Is mentioned. These may be used alone or in combination of two or more.

The curing agent is not particularly restricted but includes, for example, benzoyl peroxide, lauroyl peroxide, methyl ethyl ketone peroxide, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxy octoate and t-butyl peroxy octoate. Butylperoxybenzoate, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, bis (4-
t-butylcyclohexyl) peroxydicarbonate, 1,1-bis (t-hexylperoxy) -3,
Organic peroxides such as 3,5-trimethylcyclohexane;
Examples include radical polymerization initiators such as azo compounds such as 2,2'-azobisisobutyronitrile and 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile.

The thickener is not particularly restricted but includes, for example, polyvalent metal oxides such as magnesium oxide, calcium oxide and zinc oxide; and polyvalent metal hydroxides such as magnesium hydroxide, calcium hydroxide and aluminum hydroxide. Products; polyfunctional isocyanates and the like.

The internal release agent is not particularly limited.
Examples include stearic acid, zinc stearate, aluminum stearate, calcium stearate, barium stearate, stearic acid amide, lauric acid, triphenyl phosphate, alkyl phosphate, and the like. Further, generally used release agents such as waxes and silicone oil can also be used. The colorant is not particularly limited, and includes, for example, inorganic pigments, organic pigments, and toners that can be used in thermosetting resins.

The chain transfer agent is not particularly limited.
For example, α-methylstyrene dimer, carbon tetrachloride, etc.
As a thiol compound, t-butyl mercaptan, n-
Alkyl mercaptans such as octyl mercaptan and n-dodecyl mercaptan; aromatic mercaptans such as thiophenol and thionaphthol; thioglycolic acid; octyl thioglycolate; ethylene glycol dithioglycolate; trimethylolpropane tris- (thioglycolate); Thioglycolic acid alkyl esters such as erythritol tetrakis- (thioglycolate);
β-mercaptopropionic acid; octyl β-mercaptopropionate, 1,4-butanediol di (β-thiopropionate), trimethylolpropane tris- (β
-Thiopropionate) and β-mercaptopropionic acid alkyl esters such as pentaerythritol tetrakis- (β-thiopropionate).

The polymerization inhibitor is not particularly limited.
For example, pt-butylcatechol, p-methoxyphenol, hydroquinone, p-benzoquinone, chloranil, m-dinitrobenzene, nitrobenzene, p-phenyldiamine, sulfur, diphenylpicrylhydrazyl,
Di-p-fluorophenylamine, tri-p-nitrophenylmethyl and the like.

The ultraviolet absorber is not particularly limited, and for example, those which can be used for thermosetting resins such as benzophenone and benzotriazole can be used. The viscosity reducing agent, the coupling agent, and the antibacterial agent are not particularly limited, and for example, those that can be used for a thermosetting resin can be used.

The filler in the present invention preferably contains aluminum hydroxide as an essential component, since the basic performance such as the strength of the artificial stone plate is improved, and may contain other components. The other components are not particularly limited, and include, for example, inorganic materials such as calcium carbonate, calcium sulfate, barium sulfate, alumina, clay, talc, milled fiber, silica (silica sand), river sand, diatomaceous earth, mica powder, gypsum, and glass powder. Fillers: organic fillers, fiber reinforcing materials and the like. These may be used alone or in combination of two or more.

The fiber reinforcing material is not particularly limited.
For example, inorganic fibers such as glass fibers, carbon fibers, metal fibers, and fibers made of ceramic; organic fibers made of aramid, polyester, and the like; and natural fibers. Further, the form of these fibers is not particularly limited, and examples thereof include roving, chopped strand, mat, cloth (woven fabric), and the like.

The granular natural stone in the present invention is not particularly limited as long as the natural stone is granulated. Also,
Pottery, porcelain, glass, stationary glass, and the like can also be used.

The material of the natural stone is not particularly limited. Examples thereof include igneous rocks such as granite and andesite; sedimentary rocks such as sandstone and tuff; metamorphic rocks such as marble, slate, and serpentine; No. These may be used alone or in combination of two or more. Among them, granite is preferable because the artificial stone plate has excellent surface hardness and chemical resistance. The granite is not particularly limited, and examples thereof include granites such as Fujioka Mikage and Manari Mikage, mahogany, Belfast, Verdefontan and the like.

The particle size range of the granular natural stone is not particularly limited, and is preferably 30 mm or less, more preferably 1 to 15 mm. If it exceeds 15 mm, there is a possibility that breakage and abrasion of the granular natural stone cannot be suppressed in the kneading step. Moreover, there is a possibility that the kneading machine may be damaged. Furthermore, since the fluidity of the composition for artificial slabs is inferior, workability at the time of production is reduced, and filling in a mold in a molding step may be insufficient. Further, the maximum particle size is preferably 20 mm or less. More preferably, it is 13 mm or less.

The particle size distribution of the granular natural stone is not particularly limited. For example, when forming a plate having a thickness of 13.5 mm, the following particle size distribution is preferable. Particles having a particle size of 6 mm or more: 0 to 15% by weight Particles having a particle size of 5 mm to less than 6 mm: 0 to 30% by weight Particles having a particle size of 4 mm to less than 5 mm: 5 to 30% by weight Particles having a particle size of 3 mm to less than 4 mm: 5 Particles having a particle size of 2 to less than 3 mm: 10 to 50% by weight Particles having a particle size of 1 to 2 mm: 5 to 50% by weight Particles having a particle size of less than 1 mm: 0 to 10% by weight The total amount is 100% by weight.

If the distribution of the particles having a particle size of 5 mm or more exceeds the above range, there is a possibility that in the kneading step, breakage and abrasion of the granular natural stone cannot be suppressed. Moreover, there is a possibility that the kneading machine may be damaged. Furthermore, since the fluidity of the composition for artificial stone slabs is inferior, the workability at the time of production is reduced, and the filling in the mold may be insufficient. 10% by weight of particles having a particle size of less than 1 mm
When it exceeds, blackening may occur on the artificial stone plate. When the distribution of particles having a particle size of 1 mm or more and less than 5 mm exceeds the above range, the particle size distribution becomes nearly uniform, so that the pattern of the granular natural stone formed on the surface of the artificial stone plate may be difficult to approximate natural stone. .

The average particle size of the granular natural stone is not particularly limited, but is preferably 3 to 8 mm. 3m
When it is less than m, the particle size distribution becomes nearly uniform, and the pattern of the granular natural stone formed on the surface of the artificial stone plate may be difficult to approximate natural stone. If it exceeds 8 mm, there is a possibility that breakage or abrasion of the granular natural stone cannot be suppressed in the kneading step. Moreover, there is a possibility that the kneading machine may be damaged. Furthermore, since the fluidity of the composition for artificial slabs is inferior, workability during production is reduced,
In the molding step, there is a possibility that filling in the mold may be insufficient. More preferably, it is 4 to 7 mm. The type of the particulate natural stone and the state of the particles are factors that determine the appearance and basic performance of the artificial stone plate of the present invention, and can be appropriately selected according to the use of the artificial stone plate to be obtained.

In the present specification, the maximum grain size of the granular natural stone is defined as the maximum grain size b which passes through a sieve having an aperture of (b + d) mm (where d> 0) and remains on a bmm sieve.
mm. In the present specification, the particle size distribution of the granular natural stone means, for the granular natural stone before being put into the kneading machine, means the distribution of the particle size of each particle constituting the granular natural stone, the horizontal axis is the particle size, the vertical axis Can be expressed by the weight ratio (% by weight) of the particles having each particle size. The particle size distribution can be measured according to the sieving method of JIS Z8815.

In the present specification, the average particle size means a representative particle size. The above-mentioned representative particle diameter means the particle size on the horizontal axis and the weight ratio (% by weight) of particles having each particle size on the vertical axis.
Is used to represent the particle size distribution of the granular natural stone, the weight ratio (% by weight) of each particle size is accumulated from the minimum particle size in the direction of increasing the particle size, and the total is 50% by weight.

In the method for producing an artificial stone slab, the types and amounts of each component in the matrix resin, the filler and the granular natural stone, the combination thereof, the molding conditions for forming the artificial slab, or the artificial slab May be appropriately set in accordance with the basic performance required for the above, its use, and the like, and there is no particular limitation.

The amount of use of the above-mentioned low shrinkage agent in the above matrix resin is preferably 0 to 50 parts by weight based on 100 parts by weight of the thermosetting resin. If it exceeds 50 parts by weight, the basic performance such as the strength of the artificial slab may be reduced. The amount of the thickener used in the matrix resin can be appropriately set according to the weight average molecular weight and the viscosity of the thermosetting resin.

The amount of the filler is preferably 30 to 300 parts by weight based on 100 parts by weight of the matrix resin. When the amount is less than 30 parts by weight, the basic performance such as the strength of the artificial slab may be reduced. There is.
In the filler, the aluminum hydroxide is preferably 50 to 100% by weight based on the total amount of the filler. When the content is less than 50% by weight, the basic performance such as the strength of the artificial stone plate may be reduced. More preferably, 70
１００100% by weight.

The amount of the granulated natural stone used is preferably 50 to 1000 parts by weight based on 100 parts by weight of the matrix resin. When the amount is less than 50 parts by weight, the basic performance such as strength and surface hardness of the artificial stone plate and the design may be deteriorated. When the amount exceeds 1000 parts by weight, the fluidity of the composition for the artificial stone plate is inferior. The filling property may be reduced. More preferably, 300
８００800 parts by weight.

The production of the artificial slab is performed by kneading a matrix material containing a matrix resin and a filler and granular natural stone into a kneader to obtain a composition for the artificial slab, and
A molding step of molding the composition for artificial stone slabs to obtain a plate-like molded product, and, if necessary, a surface polishing step of polishing the surface of the molded product. In molding the composition for artificial stone slabs, if necessary, a preforming step is preferably performed to mold the composition for artificial stone slabs using a preform of the composition for artificial stone slabs.

The kneading step is performed in order to obtain a composition for an artificial stone plate by sufficiently kneading the components constituting the matrix material and the particulate natural stone to disperse the granular natural stone in the matrix material. The composition for an artificial slab is obtained by the kneading step, and is a composition in which the above-described components are kneaded.

In the kneading step, for example, first, a part or all of the matrix resin is prepared with a stirrer such as a disper, then charged into a kneader such as a kneader and kneaded, and then the remaining components are sequentially kneaded with a kneader or the like. Kneading with a machine can be performed.

The type of the kneading machine such as the above kneader is not particularly limited. Examples thereof include a sigma blade type and a Banbury type. The matrix material is obtained by shaving the kneading blade of the kneader or the inner wall of the container. In order to suppress darkening, it is preferable that a ceramic chip is attached to the kneading blade and the inner wall of the container.

The rotation speed and temperature of kneading in the kneader such as the above kneader are not particularly limited, but in order to sufficiently knead the matrix material and granular natural stone, the rotation speed is 20 to 50 rpm and the temperature is 10 to 60 ° C. It is preferable to set More preferably, the temperature is 15 to 40 ° C
It is. In the kneading step, the order of charging the above-described components to the kneader and other kneading methods are not particularly limited.

In the molding step of the present invention, the artificial stone slab composition is preliminarily molded, if necessary, and the artificial stone slab composition preform is charged into a mold and molded. This is performed to obtain a shaped article.

In the present specification, the preforming means a composition for an artificial stone plate obtained in a kneading step in order to facilitate charging of a mold and to improve the filling property of the composition for an artificial stone plate. For example, the method is performed by preform packing in which the composition for artificial slabs is packed in a container or the like, or by extruding with an extruder.

The preform of the composition for artificial stone board is obtained by the preform. The composition for artificial stone slabs and the preform of the composition for artificial stone slabs are usually also referred to as bulk molding compound (BMC).
The method of packing the preform is not particularly limited,
For example, it may or may not be aged at room temperature.

In the above molding step, for example, after charging the preform of the composition for artificial stone slab in a heated mold, pressurization is performed by pressing the lower mold (lower mold) and the upper mold (upper mold). ), The preform of the artificial stone slab composition is spread and filled in a mold, and can be performed by pressure molding such as press molding (compression molding) in which the composition is held for a predetermined time.

In the present specification, charging the artificial stone slab composition preform to the mold means arranging the artificial stone slab composition preform on the lower mold (lower mold). . The method for arranging the composition preform for the artificial slab is not particularly limited.

The above-mentioned mold can be charged by a BMC charge machine or the like, and the molded plate-like molded product can be taken out of the mold by a product take-out machine or the like. The pressure of the mold is, for example, 50 to 20.
It can be performed at 0 kgf / cm ² .

The heating temperature of the mold is not particularly limited, but is preferably from 100 to 170 ° C. Further, the upper mold and the lower mold may be at the same temperature or different temperatures. The molding time during which the mold is pressed is not particularly limited, but is preferably 180 to 700 seconds. Heating temperature is less than 100 ° C or molding time is 1
If the time is less than 80 seconds, the composition of the artificial stone plate may be insufficiently cured, and if it exceeds 700 seconds, it is not economical. If the heating temperature exceeds 170 ° C., the basic performance, design, and luxury of the artificial slab may be reduced.

In the above-mentioned molding step, a plate-like molded product obtained by molding the above-mentioned composition for artificial stone plate causes a whitening phenomenon or molding defects such as nests, pinholes, cracks, etc., resulting in defective products. When the ratio (rejection rate) increases, it becomes impossible to stably produce an artificial stone slab having uniform basic performance over the entire surface, having excellent design properties, and a high-grade feel. Further, if the defective rate increases even if the used amount of the granular natural stone is increased in order to enhance the design property of the obtained artificial slab, it becomes impossible to stably produce the artificial slab having the improved design property. In order to solve this, in the above-mentioned molding step, when the composition for artificial stone slabs is spread and cured in a mold, a whitening phenomenon occurs, or molding defects such as nests and pinholes occur. It is necessary to dispel the cause.

[0061] In the present specification, the whitening phenomenon means that a large number of fine bubbles are formed on the surface of a plate-like molded product, so that the appearance of the plate-like molded product is so white as to impair the design and the sense of quality. In the present specification, the term “nest” refers to a dent formed on the surface of a plate-like molded product and a defect formed on an end of the plate-like molded product.

In the present specification, “excellent in design”
And, the granular natural stone dispersed in the matrix,
By exhibiting various colors, shapes, patterns, and the like, it is meant that the appearance of the artificial stone plate such as a pattern or pattern formed on the surface gives a good impression to a viewer. In addition, in the present specification, "having a sense of quality" means that the natural granules dispersed in the matrix and the matrix having sufficient transparency are the same as the natural stones such as granite and marble originally possessed by the natural granules. It means that a luxurious feeling appears on the surface of the artificial stone slab.

The present inventors have conducted intensive studies and as a result, the amount of the granulated natural stone introduced in the kneading step was 30 to 90% by weight based on the total amount of the matrix material and the granulated natural stone.
And the flow resistance value of the composition for artificial stone slabs used in the molding step has a basic performance uniform over the entire surface by being 0.5 to 5 t.
In addition, the present inventors have found that an artificial stone slab excellent in design and having a high-class feeling can be stably manufactured, and the present invention has been completed.

If the amount of the granulated natural stone input in the kneading step is less than 30% by weight with respect to the total amount of the matrix material and the granulated natural stone, the basic performance such as the surface hardness of the artificial stone plate may be reduced. is there. Moreover, since the amount of the granular natural stone on the surface of the artificial stone plate is reduced, the design property may be reduced. If the content exceeds 90% by weight, the fluidity when molding the composition for artificial slate may decrease, and the basic performance such as the strength of the artificial slate may decrease. The defect rate may increase. When the flow resistance value of the composition for artificial slabs used in the molding step is less than 0.5 t, the composition for artificial slabs becomes difficult to handle.
If t is exceeded, the defective rate will increase.

The amount of the above-mentioned granular natural stone is in the above-mentioned range,
In addition, the reason why the defect rate becomes low when the flow resistance value is in the above range is not necessarily clear, but the following reasons can be considered. That is, when the composition for artificial stone slabs is spread in a mold, due to the fact that granular natural stones have inherently poor fluidity and poor compatibility with the matrix material, the composition for artificial stone slabs Of the composition for artificial stone slabs, and the plate-like molded product obtained by molding the composition for artificial stone slabs causes whitening and poor molding. When the amount of the granular natural stone is in the above range, and the flow resistance value is in the above range, the flow of the composition for artificial stone slab becomes uniform, and air bleeding of the composition for artificial stone slab is performed. As a result, the whitening phenomenon and molding defects are less likely to occur. For this reason, the defect rate is reduced, and it is possible to stably produce an artificial stone plate in which a decrease in basic performance, designability, and luxury is suppressed.

The flow resistance value of the composition for artificial stone board is as follows:
As shown in FIG. 1, under an atmosphere of 130 ° C.,
A disk with a ceramic plate attached to the surface is set up and down,
The maximum load (t: ton) applied to the upper disk when the sample is placed on the lower disk and the upper disk is lowered at a constant speed until the gap between the two disks becomes 10 mm.

The thickness of the ceramic plate is, for example, 1 m
m. The size of the disk is, for example,
The diameter can be 300 mm and the height can be 30 mm. The material of the disk may be, for example, stainless steel. The sample is the composition 1 for artificial stone slab.
kg is a cylinder having a diameter of 100 mm and a height of about 70 mm. The descending speed of the above disk is 30m
m / min.

The composition for artificial stone slab having the above-mentioned flow resistance value in the above-mentioned range includes, for example, the type, amount and combination of each component contained in the matrix material; the type, maximum particle size, average particle size, and particle size distribution of granular natural stone. Combination of matrix material and granular natural stone; relation to flow resistance of composition for artificial stone plate, such as mixing order of each component into kneader, kneading machine rotation speed, kneading time, etc. It can be obtained by appropriately setting the elements to be performed.

For example, the present inventors assume that the factors related to the flow resistance value of the composition for artificial stone plates other than the average particle size of the above-mentioned granular natural stone are the same, and that the average particle size of the above-mentioned granular natural stone and the above-mentioned flow resistance value are different. I found that they were roughly proportional. Therefore, by appropriately setting the average particle size of the granular natural stone, it is possible to obtain a composition for an artificial stone slab having the above-mentioned flow resistance value in the above range.

In the surface polishing step in the present invention, for example,
As in the case of the natural stone surface polishing step, the polishing can be performed by continuous polishing or uniaxial polishing by a wet polishing machine. By the surface polishing step, the surface of the plate-like molded product obtained by the molding step is polished by about 0.5 to 2.0 mm, and the pattern of the granular natural stone in the matrix in the obtained artificial stone plate is larger than that before the surface polishing step. It becomes clear and the design is improved.

The artificial stone slab of the present invention can be cut, drilled, joined, and so on by using general natural stone processing tools such as a wet diamond cutter, chamfering machine, and water jet, and an adhesive that can be used for natural stone. It can perform a processing step for performing bonding or the like and a construction step.

In the second method for producing an artificial stone board of the present invention, a kneading step of charging a matrix material containing a matrix resin and a filler and granular natural stone into a kneading machine to obtain a composition for an artificial stone board; A molding step of molding the composition for artificial stone slabs to obtain a plate-like molded product, the method of manufacturing an artificial stone slab, wherein the amount of granular natural stones charged in the kneading step is the sum of the matrix material and the granular natural stones 30 to 90% by weight based on the weight, and the plate thickness [a (mm)] of the plate-like molded product obtained in the above-mentioned molding step is between the maximum grain size [b (mm)] of the granular natural stone. , 0.3 <b / a <1.

The inventors of the present invention have made intensive studies and found that the amount of the granulated natural stone to be added in the kneading step is 30 to 90% by weight based on the total amount of the matrix material and the granulated natural stone.
And the plate thickness [a (mm)] of the plate-like molded product obtained in the above-mentioned forming step is 0.3 <b / a <1 between the maximum particle size [b (mm)] of the granular natural stone. It has been found that by making it have the relationship of, it is possible to manufacture an artificial stone slab having uniform basic performance over the entire surface, and further enhancing the designability or the luxurious feeling. It has been completed.

If the amount of the granular natural stone to be charged in the kneading step is less than 30% by weight based on the total amount of the matrix material and the granular natural stone, the basic performance such as the surface hardness of the artificial stone plate may be reduced. is there. In addition, since the pattern of the granular natural stone formed on the surface of the artificial stone plate decreases,
There is a possibility that the design property may decrease. If it exceeds 90% by weight, the fluidity when molding the composition for artificial slate may be reduced. Further, basic performance such as the strength of the artificial slab may be reduced. Furthermore, in a molding process, there is a possibility that a defective rate may increase.

When the value of b / a is 0.3 or less, there is a possibility that the design of the artificial slab may not be improved and the sense of quality may not be improved. When the ratio is 1 or more, the flowability of the composition for artificial stone slabs may be inferior, and thus the workability during production may be reduced. Further, in the molding step, there is a possibility that the defective rate may increase. Preferably, 0.5 <b / a <1.

The amount of the granulated natural stone is within the above range,
Also, the reason why the artificial stone slab obtained when the value of b / a is in the above-mentioned range is to enhance the design property or to enhance the luxurious feeling is not necessarily clear, but the following reasons are considered. Can be That is, the appearance of the artificial stone plate such as a pattern or pattern formed on the surface, the design becomes high when giving a very good impression to the viewer, and, like the natural stones such as granite and marble originally possessed by granular natural stones When a high-grade feeling is very well appeared on the surface of the artificial stone plate, the high-grade feeling is improved. However, the amount of the granular natural stone is in the above range, and the value of b / a is in the above range. In some cases, many patterns and patterns of granular natural stone are formed on the surface of the artificial stone plate obtained after the surface polishing step. Therefore, the appearance of the artificial stone plate gives a very good impression to the viewer, and the high-grade feeling inherent in the granular natural stone appears very well on the surface of the artificial stone plate, which enhances the design and enhances the luxury. An improved artificial stone slab can be manufactured.

In order to stably produce a plate-like molded product in which the value of b / a is within the above range, for example, the above-mentioned flow resistance value can be appropriately set.
For example, the present inventors set the above-mentioned flow resistance value to 3 to 4 t.
By so doing, it has been found that a plate-like molded product in which the value of b / a falls within the above range can be stably manufactured. Therefore, by appropriately setting the above-mentioned flow resistance value, it is possible to stably produce a plate-like molded product in which the value of b / a is within the above range.

The thickness [a (mm)] is not limited as long as it satisfies the above relationship.
It is preferably 30 mm. If it is less than 3 mm,
The artificial stone slab may not have basic performance such as sufficient strength. If it exceeds 30 mm, the maximum particle size of the granular natural stone becomes too large, so that the design property and the sense of quality of the artificial stone plate may be reduced. More preferably, 5 to 25 m
m.

The maximum particle size [b (mm)] is not limited as long as it satisfies the above relationship.
It is preferably from 1 to 29 mm. When it is less than 1 mm, the particle size distribution of the granular natural stone becomes nearly uniform, and the pattern of the granular natural stone formed on the surface of the artificial stone plate may be difficult to approximate to the natural stone. Further, since the plate thickness of the plate-like molded product is too thin, the artificial stone plate may not have basic performance such as sufficient strength. If it exceeds 29 mm, in the kneading step, there is a possibility that breakage and abrasion of the granular natural stone cannot be suppressed. Moreover, there is a possibility that the kneading machine may be damaged. Furthermore, since the fluidity of the composition for artificial slabs is inferior, workability at the time of production is reduced, and filling in a mold in a molding step may be insufficient. More preferably, it is 1.6 to 24 mm.

The artificial slab of the present invention is manufactured by the above-described method for producing an artificial slab of the first invention and the second method for producing an artificial slate of the present invention. The artificial stone slab of the present invention is unfavorable in a molding step in the production thereof due to a whitening phenomenon or a molding defect such as a nest or a pinhole in a plate-like molded product obtained by molding the composition for an artificial stone slab. Since the rate of non-defective products (rejection rate) is suppressed, it is excellent in heat resistance, strength such as compressive strength and bending strength, high impact resistance and surface hardness, low water absorption rate, and low scratch resistance. It has a uniform performance over the entire surface, has excellent design properties, and even if granite, granite, marble, or any other natural stone is used as the granulated natural stone, the high-grade feel of the natural stone is at its surface And decorative materials such as tiles and wall panels; bathtubs (bathtubs); Ter), sink (sink), bathroom panel,
Residential equipment such as a system kitchen top plate (kitchen counter) and a table top plate; which can be suitably applied to various ornaments, nameplates and the like.

[0081]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Note that “parts” indicates “parts by weight”.

Preparation Example 1 In a four-necked flask as a reactor equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer, 980 parts of maleic anhydride as α, β-unsaturated dibasic acid, After charging 3,360 parts of ethylene oxide 2-adduct of bisphenol A as a polyhydric alcohol, the inside of the flask was replaced with nitrogen gas. Next, the mixture was stirred while the maximum temperature was 215.
C., and the dehydration reaction was performed for a predetermined time. Thus, an unsaturated polyester having an acid value of 17 was obtained. Then, resin A-1 was obtained by mixing 70 parts of this unsaturated polyester, 30 parts of styrene as a vinyl monomer, and 0.02 parts of hydroquinone as a stabilizer.

Preparation Example 2 A four-necked flask as a reactor equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer was charged with 1,660 parts of isophthalic acid as a saturated dibasic acid and dicarboxylic acid as a polyhydric alcohol. After charging 1380 parts of propylene glycol, the inside of the flask was replaced with nitrogen gas. Next, the mixture was heated to a maximum temperature of 215 ° C. while stirring, and a dehydration reaction was performed for a predetermined time. As a result, a saturated polyester having an acid value of 12 was obtained. And this saturated polyester 60
By mixing 40 parts of styrene as a vinyl monomer and 0.02 part of hydroquinone as a stabilizer, a resin B-1 was obtained.

Example 1 As a thermosetting resin, an unsaturated polyester resin A-
185 parts, 15 parts of saturated polyester resin B-1 as a low-shrinking agent, KBM-5 as a coupling agent
2.0 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), 0.5 part of α-methylstyrene dimer as a chain transfer agent, and Tinuvin 320 (trade name, manufactured by Ciba Specialty Chemicals) as an ultraviolet absorber. 5 parts, 0.1 part of parabenzoquinone as a polymerization inhibitor, and 0.3 toner AT-3 (trade name, manufactured by Dainichi Seika Co., Ltd.) as a colorant
The mixture was charged into a container and stirred by a disper for 10 minutes. As the disper, MHV-10 DESPA (trade name, manufactured by Asada Tekko Co., Ltd.) was used. Then, as a curing agent, Perhexa TMH (trade name, manufactured by NOF CORPORATION)
0 parts were added, and the mixture was further stirred by a disper for 10 minutes to prepare a matrix resin.

Next, the total amount of the prepared matrix resin,
Heidilite H which is aluminum hydroxide as filler
-320 (trade name, manufactured by Showa Denko KK): 200 parts, granular natural stone having an average particle size of 1.50 mm and a maximum particle size (b) of 250 parts of Mikage Fujioka were mixed with ceramic chips, kneading wings and the inner wall of the container. Into the kneader, kneaded for 1 minute by rotating the kneader, and in a state where the kneader is rotated, chopped strand ECS06B-144 / P which is a reinforcing glass fiber as a filler.
20 parts (trade name, manufactured by Nippon Electric Glass Co., Ltd.) and 2.0 parts of SZ-2000 (trade name, manufactured by Sakai Chemical Industry Co., Ltd.) which is zinc stearate as an internal mold release agent were added and kneaded for 1 minute. Then, the kneader is stopped, and the same granular natural stone 25 as above is used.
After adding 0 parts, the kneader was again rotated and kneaded for 1 minute, and then, while the kneader was rotated, 20 parts of the same reinforced glass fiber as described above was charged and kneaded for another 2 minutes and 15 seconds to complete the kneading. . The total time for kneading by rotating the kneader was 5 minutes and 15 seconds. The kneaded material was taken out of the kneader to complete the kneading process, and was 400 mm × 400 mm
A preformed BMC was obtained by preform packing to a size of about 8 kg. The kneader was an MS open type kneader; 100 L (trade name, manufactured by Moriyama Corporation), and the rotation speed was set to 29 to 38 rpm.

The flow resistance of the preformed BMC was measured five times, and the average value was 2.0 t. As shown in FIG. 1, the flow resistance was measured by placing a stainless steel disc with a ceramic plate having a thickness of 1 mm adhered to the upper and lower surfaces under an atmosphere of 130 ° C. 1kg of BMC, 100m in diameter
m, place a cylindrical sample with a height of 70 mm,
The gap between the two stainless steel disks is 10mm
Descend at a constant speed of 30 mm / min until
Maximum load on the upper stainless steel disk (t: ton)
Was measured using a Shimadzu Autograph (AG-25TD) (trade name, manufactured by Shimadzu Corporation). As the stainless steel disk, a cylindrical disk having a diameter of 300 mm and a height of 30 mm was used.

Next, the obtained BMC was charged into a mold having dimensions of 670 mm × 2470 mm set at 135/130 ° C. by using a 2500 ton large hydraulic press with a BMC charging machine. The charge pattern of the BMC is such that six BMCs are arranged in a row in the center along the long side of the mold, and arranged so that one side of the BMC is parallel to one side of the mold. Thereafter, press molding was performed at a pressure of 80 kgf / cm ² for 420 seconds to obtain a plate-like molded product having a thickness (a) of about 13.5 mm, and the molding process was completed. Table 1 shows the value of b / a.

This molding process was performed 10 times, and the ratio (defective rate) of defective products due to whitening phenomenon, molding defects such as cavities, pinholes, cracks, etc., in the obtained plate-like molded product was determined. It was examined as a defective rate in the molding process. The results are shown in Table 1. Next, the surface was polished by about 1 mm with respect to all ten plate-shaped molded products obtained by the molding step using a wet stone polishing machine for natural stone to perform a surface polishing step, and then an artificial stone plate was obtained. The obtained artificial slab was evaluated by the method described below. The results are shown in Table 1.

[0089]Evaluation method  (1) Sensory test for design and high-grade appearance
Based on polished natural granite and marble,
Whether the design is excellent and whether it has a high-class
One person (odd number) visually observed and evaluated. In addition,
All the artificial slabs were evaluated by visual observation.
Was. The number of people who evaluated the result as excellent in design,
And the average value of the number of people who
did.

In a sensory test of the design and luxury of the obtained artificial stone plate, more than half of the evaluated persons were evaluated as “excellent in design” based on polished natural granite and marble. In this case, the artificial stone slab is considered to have excellent design properties, and when more than half of the evaluated persons evaluate "having a high-class feeling", it is considered that the artificial stone slab has a high-class feeling.

Example 2 In Example 1, the average particle size was 1.
An artificial slab was obtained in the same manner except that 95 mm and the maximum particle size (b) were 6 mm. When the flow resistance value of the BMC obtained by preforming was measured twice, the average value was 2.2 t. Table 1 shows the value of b / a. Table 1 shows the results of examining the defective rate in the forming step and the results of evaluating the obtained artificial slab by the method shown in Example 1.

Example 3 In Example 1, the average particle size was 2.
An artificial stone plate was obtained in the same manner except that Belfast having a maximum particle size (b) of 6 mm was used. When the flow resistance value of the BMC obtained by preforming was measured twice, the average value was 3.1 t. Table 1 shows the value of b / a. Table 1 shows the results of examining the defective rate in the forming step and the results of evaluating the obtained artificial slab by the method shown in Example 1.

Example 4 In Example 1, the average particle size was 2.
An artificial stone slab was obtained in the same manner except that a thing having a maximum particle size (b) of 7 mm was used. When the flow resistance value of the BMC obtained by preforming was measured twice, the average value was 3.7 t. Table 1 shows the value of b / a. Table 1 shows the results of examining the defective rate in the forming step and the results of evaluating the obtained artificial slab by the method shown in Example 1.

Example 5 In Example 1, the average particle size was 3.
An artificial stone plate was obtained in the same manner except that a mahogany having a maximum particle size (b) of 7 mm was used. When the flow resistance value of the BMC obtained by preforming was measured twice, the average value was 3.5 t. Table 1 shows the values of b / a.
It described in. The result of examining the defect rate in the molding process,
Table 1 shows the results of the evaluation of the obtained artificial stone slab by the method shown in Example 1.

Example 6 In Example 1, the average particle size was 3.
An artificial stone slab was obtained in the same manner except that Mannarikage having a maximum particle size (b) of 7.5 mm was used.
When the flow resistance value of the BMC obtained by the preliminary molding was measured twice, the average value was 4.3 t. Table 1 shows the value of b / a. Table 1 shows the results of examining the defective rate in the forming step and the results of evaluating the obtained artificial slab by the method shown in Example 1.

Example 7 In Example 1, the average particle size was 3.
An artificial slab was obtained in the same manner except that Fujioka Mikage, which was 75 mm and had a maximum particle size (b) of 12 mm, was used. When the flow resistance value of the BMC obtained by preforming was measured three times, the average value was 4.6 t. Table 1 shows the values of b / a.
It described in. The result of examining the defect rate in the molding process,
Table 1 shows the results of the evaluation of the obtained artificial stone slab by the method shown in Example 1.

Example 8 In Example 1, the average particle size was 1.
An artificial stone slab was obtained in the same manner except that Fujioka Mikage, which was 25 mm and had a maximum particle size (b) of 4.5 mm, was used.
When the flow resistance value of the BMC obtained by preforming was measured twice, the average value was 3.3 t. Table 1 shows the value of b / a. Table 1 shows the result of examining the defective rate in the forming step and the result of evaluating the obtained artificial slab by the method shown in Example 1.

Example 9 In Example 1, the average particle size was 1.
An artificial slab was obtained in the same manner except that Fujioka Mikage, which was 30 mm and had a maximum particle size (b) of 5 mm, was used. When the flow resistance value of the BMC obtained by preforming was measured twice, the average value was 3.9 t. Table 1 shows the value of b / a. Table 1 shows the results of examining the defective rate in the forming step and the results of evaluating the obtained artificial slab by the method shown in Example 1.

Comparative Example 1 In Example 1, the average particle size was 1.
In the kneading step, the kneading time was 1 minute and 15 seconds after the second reinforcing glass fiber was used, except that the maximum particle size (b) was 3.9 mm. An artificial stone slab was obtained. B obtained by preforming
When the flow resistance value of MC was measured twice, the average value was 6.
8t. Table 1 shows the value of b / a. Table 1 shows the result of examining the defective rate in the forming step and the result of evaluating the obtained artificial slab by the method shown in Example 1.

[0100]

[Table 1]

As is clear from Table 1, in Examples 1 to 9, an artificial stone slab having uniform basic performance over the entire surface, having excellent design properties, and having a high-grade appearance was obtained by lowering the defective rate. It could be obtained stably. Example 1
In Nos. To 7, it was found that the average particle size of the granular natural stone and the flow resistance value were substantially in a proportional relationship. Examples 1 to 9 in which the value of b / a is larger than 0.3 and smaller than 1.0
In the case of, an artificial stone plate with improved design properties and an improved sense of quality could be obtained.

On the other hand, in Comparative Example 1, the defect rate
It was higher than 9 Therefore, the artificial stone slabs obtained in Comparative Example 1 were inferior in basic performance as compared with the artificial stone slabs obtained in Examples 1, 2, 4, 8, and 9 using similar granular natural stones. . Further, Examples 1 to
In comparison with the artificial stone slab obtained in No. 9, it was inferior in design property and luxury.

[0103]

According to the method for producing an artificial stone slab of the present invention, since it has the above-described structure, an artificial stone slab having uniform basic performance over the entire surface, excellent design, and high-grade appearance can be stably manufactured. Is what you can do. The second method for producing an artificial stone slab of the present invention is capable of producing an artificial stone slab having uniform basic performance over the entire surface, and further having improved designability and a sense of quality.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing measurement of a flow resistance value in a method for manufacturing a long artificial stone plate of the present invention.

[Explanation of symbols]

 1 Sample of composition for artificial stone slab 2 Ceramic plate 3 Disk

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // (C04B 26/02 14:04) B29K 105: 16 (72) Inventor Koji Takahata Nishi Suita-shi, Osaka F-term (reference) 4-8, Onabicho Nippon Shokubai Co., Ltd. 4F070 AA49 AC27 AC29 AE01 AE08 FA02 FB06 FC03 4F204 AA41 AB03 AB11 AB16 AB25 AC01 AG02 AM32 FB01 FB21 FF06 4J002 BF051 BG001 BG041 BG051 BG131 CC161 CC161 CC161 DE146 DL007 DM007 FA047 FD016 FD017 GL02

Claims (3)

[Claims] 1. A kneading step in which a matrix material containing a matrix resin and a filler and granular natural stone are charged into a kneading machine to obtain a composition for artificial slate, and the composition for artificial slate is formed into a plate. A molding step of obtaining a molded product, wherein the amount of the granulated natural stone charged in the kneading step is 30 to 90% by weight based on the total amount of the matrix material and the granulated natural stone. The flow resistance value of the composition for artificial stone slab used in the molding step,
0.5 to 5 tons. 2. A kneading step of introducing a matrix material containing a matrix resin and a filler and granular natural stone into a kneading machine to obtain a composition for an artificial slab, and molding the composition for an artificial slab to form a plate. A molding step of obtaining a molded product, wherein the amount of the granular natural stone charged in the kneading step is 30 to 90% by weight based on the total amount of the matrix material and the granular natural stone. The plate thickness [a (mm)] of the plate-like molded product obtained in the molding step is 0.3 <b / a <1 between the maximum particle size [b (mm)] of the granular natural stone. A method for producing an artificial stone slab characterized by having a relationship. 3. An artificial slab obtained by the method for producing an artificial slab according to claim 1.