JP2018089934A - Production method of artificial marble - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an artificial marble having more favorable patterns.SOLUTION: A production method of an artificial marble 100 contains: a step 1 of pouring a first liquid resin composition 10 into a mold 50; a step 2 of adding a second liquid resin composition 20 which has a specific gravity larger than that of the first liquid resin composition 10 to the mold 50 and over the first liquid resin composition 10 in the mold 50; and a step 3 of curing the first liquid resin composition 10 and the second liquid resin composition 20 in the mold 50 with a part of the first liquid resin composition 10 being floating over the second liquid resin composition 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing artificial marble.

  Artificial marble is used for counters and sinks in system kitchens, counters and bowls in vanities, and bathtubs. The molded product of artificial marble can be formed, for example, by injecting a resin composition for artificial marble into a mold and curing it.

  Patent Document 1 discloses a continuous production apparatus for artificial marble (artificial marble) having a stripe pattern. This apparatus includes a moving molding cell, a liquid resin supply means for laminating different color liquid resins (liquid resin composition) on the molding cell, and a comb arranged with teeth in contact with the bottom surface of the molding cell. And a cam device for reciprocating the comb-shaped tool in a direction perpendicular to the cell moving direction.

JP 2000-343537 A

  When the liquid resin composition of different colors laminated on the molding cell is mixed with a comb-like tool that reciprocates by a cam device, the stripe pattern formed on the artificial marble tends to become periodic. As a result of the test research, the present inventor has found a novel manufacturing method of artificial marble.

  The present invention discloses a production method capable of producing artificial marble having a better pattern.

The method for producing an artificial marble of the present invention includes a step of pouring the first liquid resin composition into a mold,
Adding a second liquid resin composition having a specific gravity greater than that of the first liquid resin composition into the mold from above the first liquid resin composition in the mold;
Curing the first liquid resin composition and the second liquid resin composition in a state where a part of the first liquid resin composition floats on the second liquid resin composition in the mold. And a step of causing a step.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method which can manufacture the artificial marble of a further favorable pattern can be provided.

The figure which shows typically the example of the manufacturing method of artificial marble. 2A and 2B are diagrams schematically showing an example of the surface of an artificial marble. The photograph which shows the cross section of the artificial marble sample of the comparative test area 2-1. The photograph which shows the cross section of the artificial marble sample of the comparative test section 2-3. The photograph which shows the cross section of the artificial marble sample of the test area 2-6. The photograph which shows the cross section of the artificial marble sample of the test area 2-7. The photograph which shows the surface of the artificial marble sample of the test area 4-1. The photograph which shows the surface of the artificial marble sample of the test area 4-2. The photograph which shows the surface of the artificial marble sample of the test area 5-1. The photograph which shows the surface of the artificial marble sample of the test area 5-2.

  Embodiments of the present invention will be described below. Of course, the following embodiments are merely examples of the present invention, and all the features shown in the embodiments are not necessarily essential to the means for solving the invention.

(1) Summary of technology included in the present invention:
First, the outline of the technology included in the present invention will be described with reference to the examples shown in FIGS. In addition, the figure of this application is a figure which shows an example typically, The expansion ratio of each direction shown by these figures may differ, and each figure may not match. Of course, each element of the present technology is not limited to the specific example indicated by the reference numeral. In the present application, “Min to Max” means a minimum value Min or more and a maximum value Max or less.

[Aspect 1]
The manufacturing method of the artificial marble 100 which concerns on 1 aspect of this technique includes the following processes 1-3.
(Step 1) A step of pouring the first liquid resin composition 10 into the mold 50.
(Step 2) A second liquid resin composition 20 having a specific gravity greater than that of the first liquid resin composition 10 is placed on the first liquid resin composition 10 in the mold 50 into the mold 50. Adding process.
(Step 3) The first liquid resin composition 10 and the first liquid resin composition 10 are partially floated on the second liquid resin composition 20 in the mold 50. A step of curing the second liquid resin composition 20.

  When the second liquid resin composition 20 having a higher specific gravity than the first liquid resin composition 10 is added into the mold 50 from above the first liquid resin composition 10, the first liquid resin is formed in the mold 50. A part of the composition 10 floats on the second liquid resin composition 20. It has been found that when the first liquid resin composition 10 and the second liquid resin composition 20 are cured in this state, an artificial marble 100 having an unprecedented pattern is obtained. Therefore, the said aspect 1 can provide the manufacturing method which can manufacture the artificial marble of a further favorable pattern.

Here, the first liquid resin composition may be one type or two or more types. The second liquid resin composition may also be one type or two or more types.
The first liquid resin composition and the second liquid resin composition may be different colors or the same color. Even if the first liquid resin composition and the second liquid resin composition are the same color, a good pattern is expressed if the refractive index and reflectance are different.

[Aspect 2]
As illustrated in FIG. 1, the second liquid resin composition 20 may include a plurality of liquid resin compositions having different colors (for example, liquid resin compositions 21 and 22). In this aspect, since a plurality of colors are expressed by the second liquid resin composition (21, 22), it is possible to provide a manufacturing method capable of manufacturing an artificial marble having a better pattern.
Here, the mold may be fixed so as not to move when the liquid resin composition enters, or may move when the liquid resin composition enters. The moving mold may be a continuous mold in which concave portions into which the liquid resin composition enters are continuous in the moving direction, and the artificial marble may be a cut product of a molded product cured in the continuous mold.
The second liquid resin composition may include two types of liquid resin compositions or may include three or more types of liquid resin compositions.
The first liquid resin composition may also include a plurality of liquid resin compositions having different colors.

[Aspect 3]
The specific gravity of the second liquid resin composition 20 may be 0.03 or greater than the specific gravity of the first liquid resin composition 10. In this aspect, since a part of the first liquid resin composition 10 is likely to float on the second liquid resin composition 20 in the mold 50, a manufacturing method capable of manufacturing artificial marble with a better pattern is provided. Can be provided.

(2) Specific examples of manufacturing method of artificial marble:
FIG. 1 schematically shows an example of a method for producing artificial marble. The manufacturing method of the artificial marble 100 shown in FIG. 1 includes the step 1 of pouring the first liquid resin composition 10 into the mold 50, and the mold 50 from above the first liquid resin composition 10 in the mold 50. Step 2 of adding the second liquid resin composition 20 having a specific gravity greater than that of the first liquid resin composition 10, and a part of the first liquid resin composition 10 in the mold 50 being the second liquid resin composition And the step 3 of curing the first liquid resin composition 10 and the second liquid resin composition 20 in a state of floating on the object 20. The second liquid resin composition 20 may include a plurality of liquid resin compositions having different colors (for example, high specific gravity liquid resin compositions 21 and 22). The second liquid resin composition 20 shown in FIG. 1 generically refers to the high specific gravity liquid resin compositions 21 and 22.

(Examples of liquid resin compositions 10 and 20)
The components contained in the liquid resin compositions 10 and 20 may be the same or different as long as the specific gravity of the second liquid resin composition 20 is greater than the specific gravity of the first liquid resin composition 10. . The liquid resin compositions 10 and 20 may be any curable resin composition that has fluidity and is cured after molding. For example, a thermosetting resin composition can be used. Such a thermosetting resin composition includes at least one of an unsaturated polyester resin composition, a vinyl ester resin composition, an acrylic resin composition, an epoxy resin composition, a phenol resin composition, a urea resin composition, and the like. Can be used. As the liquid resin composition, a resin composition containing a polymerizable solution in which at least a polymer is dissolved in a liquid polymerizable monomer or the like can be used. Here, the polymerizable monomer or the like is one or more substances selected from a polymerizable monomer and an oligomer thereof.

  As the polymerizable monomer contained in the polymerizable solution, a radical polymerizable monomer that is polymerized by a radical polymerization reaction can be used. As such radical polymerizable monomers, aromatic vinyl compound monomers, acrylate ester monomers, vinyl compound monomers, allyl compound monomers, oligomers thereof, and the like can be used. For example, styrene, α -Methylstyrene, vinyltoluene, chlorostyrene, dichlorostyrene, t-butylstyrene, vinylnaphthalene, ethyl vinyl ether, methyl vinyl ketone, methyl methacrylate (also known as methyl methacrylate), ethyl acrylate, ethyl methacrylate, acrylonitrile, methacrylonitrile, Diallyl phthalate, diallyl terephthalate, diallyl succinate, triallyl cyanurate, oligomers thereof and the like can be used. These radically polymerizable monomers and the like may be used alone or in combination of two or more. In particular, styrene (styrene monomer) is a cheap, versatile and preferred chemical substance.

  The compounding ratio of the radically polymerizable monomer or the like in the polymerizable solution is not particularly limited, and can be, for example, 30 to 500 parts by weight, more preferably 40 to 400 parts by weight with respect to 100 parts by weight of the polymer. If the blending ratio of the radically polymerizable monomer or the like is increased, the viscosity of the liquid resin composition can be lowered, and if the blending ratio of the radically polymerizable monomer or the like is decreased, the viscosity of the liquid resin composition can be increased.

  Examples of the polymer contained in the polymerizable solution include known polyesters such as unsaturated polyesters (polyesters having unsaturated groups), vinyl esters, acrylic polymers such as polyacrylic acid, and the like that are contained in thermosetting resin compositions. One or more polymers can be used. The unsaturated polyester can be obtained, for example, by reacting an unsaturated dicarboxylic acid added with a saturated dicarboxylic acid (for example, an unsaturated dibasic acid such as maleic anhydride or fumaric acid) with a dihydric alcohol.

  An additive such as a polymerization inhibitor may be added to the polymerizable solution. The polymerization inhibitor includes one or more of hydroquinone, p-benzoquinone, methylhydroquinone, trimethylhydroquinone, t-butylhydroquinone, catechol, t-butylcatechol, 2,6-di-t-butyl-4-methylphenol, and the like. Can be used.

  In the liquid resin composition containing the polymerizable solution described above, a filler, a colorant, a thermoplastic polymer, a mold release agent, a thickener, a reinforcing agent, a curing agent, and a curing accelerator are used as long as the effects of this technology are not impaired. One or more additives such as an agent (curing aid), a polymerization regulator, an ultraviolet absorber, a flame retardant, and an antioxidant may be added.

  For example, at least one of an inorganic filler and an organic filler can be used as the filler. The inorganic filler includes at least one of calcium carbonate, aluminum hydroxide, glass powder, silica, barium sulfate, magnesium carbonate, alumina, aluminum silicate, magnesium silicate, calcium sulfate, magnesium hydroxide, calcium hydroxide, etc. A hollow lightweight material called a balloon (for example, a foam) may be used. As the inorganic balloon, one or more of silica balloon, glass balloon, shirasu balloon, carbon balloon, alumina balloon, zirconia balloon, and the like can be used. When an inorganic filler is used, it is expected to impart flame retardancy to the resulting artificial marble and improve the surface hardness of the artificial marble. As the organic filler, one or more of wood powder, cured resin, and the like can be used, and a hollow lightening material called a balloon may be used. As the organic balloon, a resin balloon or the like can be used. When a filler is used, it is expected to reduce shrinkage of a molded product at the time of curing.

The filler can be used to provide a specific gravity difference between the liquid resin compositions 10 and 20. In general, when an inorganic filler other than an inorganic balloon is added to a polymerizable solution, the specific gravity of the polymerizable solution increases. Therefore, even if an inorganic filler other than the inorganic balloon is used for the second liquid resin composition 20 in order to make the specific gravity of the second liquid resin composition 20 larger than the specific gravity of the first liquid resin composition 10. Good. Moreover, when a balloon is added to the polymerizable solution, the specific gravity of the polymerizable solution is reduced. Therefore, in order to make the specific gravity of the first liquid resin composition 10 smaller than the specific gravity of the second liquid resin composition 20, a hollow lightweight material may be used for the first liquid resin composition 10. Of course, the first liquid resin composition 10 and the first liquid resin composition 10 are used, such as using a hollow lightweight material and the second liquid resin composition 20 using an inorganic filler excluding an inorganic balloon. Different fillers may be used for the second liquid resin composition 20.
The filler may be used to make the first liquid resin composition 10 and the second liquid resin composition 20 different colors, or the liquid resin contained in the second liquid resin composition 20. Compositions 10 and 20 may be used to make the colors different from each other.

  The average particle diameter of a filler is not specifically limited, For example, it can be 0.1-100 micrometers. In the case of using a filler, the blending ratio of the filler in the liquid resin compositions 10 and 20 is not particularly limited, and is, for example, 5 to 600 parts by weight, more preferably 10 to 100 parts by weight with respect to 100 parts by weight of the polymerizable solution. It can be 400 parts by weight.

  As the colorant, at least one of an inorganic colorant and an organic colorant can be used, and a pigment may be used or a dye may be used. Inorganic colorants include white pigments such as titanium oxide, zinc oxide and zinc sulfide, yellow pigments such as iron oxide yellow, black pigments such as carbon black and iron oxide black, red pigments such as iron oxide red, blue pigments such as ultramarine blue, etc. One or more of the above can be used. As the organic colorant, one or more of a blue pigment such as phthalocyanine blue, a yellow pigment such as isoindolinone yellow, and an orange pigment such as diketopyrrolopyrrole can be used. The colorant may be used to make the first liquid resin composition 10 and the second liquid resin composition 20 different colors, or the liquid resin composition contained in the second liquid resin composition 20. 10 and 20 may be used to make the colors different from each other.

  As the reinforcing agent, at least one of inorganic fibers and organic fibers can be used. As the inorganic fiber, one or more of glass fiber, carbon fiber, and the like can be used. As the organic fiber, one or more of synthetic resin fibers such as polyester fibers and polyamide fibers can be used. Although the length of a fiber is not specifically limited, For example, it can be set as 0.5-6 mm. In the case of using a reinforcing agent, the compounding ratio of the reinforcing agent in the liquid resin compositions 10 and 20 is, for example, 1 to 40 parts by weight, more preferably 2 to 35 parts by weight with respect to 100 parts by weight of the polymerizable solution. be able to. A reinforcing agent can be used to provide a specific gravity difference between the liquid resin compositions 10 and 20.

  As the thermoplastic polymer, a thermoplastic resin or the like can be used. For example, polyvinyl acetate, polybutadiene, polyethylene terephthalate (PET), polystyrene, or the like can be used. When the thermoplastic polymer is used, it is expected that the shrinkage of the molded product at the time of curing is reduced and the smoothness of the surface of the artificial marble is improved. When using a thermoplastic polymer, the compounding ratio of the thermoplastic polymer in the liquid resin compositions 10 and 20 can be, for example, 5 to 30 parts by weight with respect to 100 parts by weight of the polymerizable solution.

  As the release agent, one or more of a fatty acid release agent, a fluorine release agent, a silicon release agent, and the like can be used, for example, one or more of a metal soap, a phosphate ester compound, a wax, and the like. Can be used.

  As the thickener, one or more of metal oxides such as magnesium oxide, diisocyanate compounds, and the like can be used. When using a thickener, the compounding ratio of the thickener in the liquid resin compositions 10 and 20 can be, for example, 0.5 to 10 parts by weight with respect to 100 parts by weight of the polymerizable solution.

  As the curing agent, one or more of an organic peroxide, an azo compound, and the like can be used. For example, methyl ethyl ketone peroxide, acetylacetone peroxide, t-butylperoxybenzoate, benzoyl peroxide, dicumyl peroxide, cumene Use one or more of hydroperoxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexaate, t-hexylperoxy-2-ethylhexanoate, azobisisobutyronitrile, etc. Can do. When using a hardening | curing agent, the compounding ratio of the hardening | curing agent in the liquid resin compositions 10 and 20 can be 0.1-5 weight part with respect to 100 weight part of polymeric solutions, for example. In addition, when the compounding ratio of the curing agent is increased, the curing time of the liquid resin composition is shortened, and the first liquid resin composition 10 that floats and the second liquid resin composition 20 that settles can be reduced. . On the other hand, when the blending ratio of the curing agent is decreased, the curing time of the liquid resin composition becomes longer, and the first liquid resin composition 10 that floats and the second liquid resin composition 20 that settles can be increased. . Therefore, the pattern formed on the surface of the artificial marble can be changed by adjusting the blending ratio of the curing agent.

  Curing accelerators (curing aids) include cobalt naphthenate, cobalt octoate, N, N-dimethylaniline, N, N-diethylaniline, N, N-dimethyl-p-toluidine, acetylacetone, acetoacetic acid ethyl ester, One or more of tertiary amine, benzyldimethylamine, tin octylate, bicyclic amidine compound, quaternary phosphonium salt, quaternary ammonium salt, and the like can be used.

  The specific gravity difference obtained by subtracting the specific gravity of the first liquid resin composition 10 from the specific gravity of the second liquid resin composition 20 is preferably 0.03 or more. When the specific gravity difference is 0.03 or more (more preferably 0.06 or more, more preferably 0.1 or more), the first liquid resin composition 10 floats in the mold and the second liquid resin composition 20 Sedimentation is improved, thereby improving the appearance of the artificial marble on which the pattern is formed. In addition, since the floating of the 1st liquid resin composition 10 and the sedimentation of the 2nd liquid resin composition 20 become favorable in a type | mold, so that specific gravity difference is large, the upper limit of specific gravity difference is not specifically limited.

The first liquid resin composition 10 and the second liquid resin composition 20 may be different colors. Here, the colors of the liquid resin compositions 10 and 20 include transparency. Therefore, the case where the liquid resin compositions 10 and 20 are different in color includes the following cases.
1. The first liquid resin composition is colorless and transparent, and the second liquid resin composition has a color such as a colorant or a filler.
2. The second liquid resin composition is colorless and transparent, and the first liquid resin composition has a color such as a colorant or a filler.
3. The first liquid resin composition has a first color such as a colorant or a filler, and the second liquid resin composition has a second color such as a colorant or a filler. And the second color is different.

Further, the color of the plurality of high specific gravity liquid resin compositions (for example, the high specific gravity liquid resin compositions 21 and 22) included in the second liquid resin composition 20 also includes transparency. For example, the case where the high specific gravity liquid resin compositions 21 and 22 are different from each other includes the following cases.
1. The high specific gravity liquid resin composition 21 is colorless and transparent, and the high specific gravity liquid resin composition 22 has a color such as a colorant or a filler.
2. The high specific gravity liquid resin composition 22 is colorless and transparent, and the high specific gravity liquid resin composition 21 has a color such as a colorant or a filler.
3. The high specific gravity liquid resin composition 21 has a first color such as a colorant or a filler, and the high specific gravity liquid resin composition 22 has a second color such as a colorant or a filler. And the second color is different.
Note that any one of the plurality of high specific gravity liquid resin compositions may have the same color as the first liquid resin composition 10.

  The viscosity of the liquid resin compositions 10 and 20 immediately before entering the mold 50 can be set to 0.1 to 30 Pa · s, for example. Here, the viscosity is a Brookfield type rotational viscometer B specified in JIS K7117-1: 1999 (plastic-liquid, emulsion or dispersion resin-a method for measuring an apparent viscosity with a Brookfield type rotational viscometer). The viscosity measured in the form. In this specific example, the temperature was set to 28 ° C. during the measurement, and the rotor No. 3 was used at a rotational speed of 6 rpm. When the viscosity of the liquid resin composition is 0.1 Pa · s or higher, the first liquid resin composition 10 and the second liquid resin composition 20 are not mixed too much, and a good pattern is formed on the artificial marble. preferable. Moreover, when the viscosity of the liquid resin composition is 30 Pa · s or less, the first liquid resin composition 10 is easily levitated and the second liquid resin composition 20 is precipitated, and a good pattern is formed on the artificial marble. Therefore, it is preferable.

(Process 1)
In order to manufacture the artificial marble 100, first, the first liquid resin composition 10 having a relatively small specific gravity is poured into the mold 50. In FIG. 1, the example of the manufacturing apparatus of the artificial marble 100 is shown typically. The mold 50 of this manufacturing apparatus has a recess 51 whose upper surface is open. A bottom surface 51b of the recess 51 shown in FIG. 1 is a surface on which the surface 101 of the artificial marble 100 is formed directly or indirectly. As a material for forming the mold 50, metal, glass, fiber reinforced plastic (FRP), or the like can be used. The supply part 60 of the 1st liquid resin composition 10 has the supply port 60a which pours the 1st liquid resin composition 10 on the bottom face 51b. The first liquid resin composition 10 in the supply unit 60 may be degassed under reduced pressure. When the first liquid resin composition 10 is degassed, bubbles can be prevented from being mixed into the artificial marble 100. The supply port 60a may flow out the first liquid resin composition 10 while moving on the recess 51. In the case where the bottom surface 51b of the recess is planar, the thickness T1 on the bottom surface 51b of the first liquid resin composition 10 that has entered the recess 51 is not particularly limited, but may be, for example, 0.5 to 10 mm. it can.
In addition, what is necessary is just to prepare a supply part for every kind of small specific gravity liquid resin composition, when the 1st liquid resin composition 10 contains several low specific gravity liquid resin composition.

(Process 2)
Next, the second liquid resin composition 20 having a relatively large specific gravity is added into the mold 50 from above the first liquid resin composition 10 in the mold 50. In FIG. 1, the supply unit 70 of the second liquid resin composition 20 has a supply port 70 a for flowing the second liquid resin composition 20 onto the first liquid resin composition 10 in the recess 51. It has been shown that When the second liquid resin composition 20 includes the high specific gravity liquid resin compositions 21 and 22, the supply unit 70 is divided into a supply unit 71 having a supply port 71a and a supply unit 72 having a supply port 72a. May be. In FIG. 1, the high specific gravity liquid resin composition 21 flows out from the supply port 71 a onto the first liquid resin composition 10 in the recess 51, and the high specific gravity liquid resin composition 22 flows from the supply port 72 a into the recess 51. It is shown that it flows out onto the first liquid resin composition 10. The large specific gravity liquid resin compositions 21 and 22 in the supply units 71 and 72 may be degassed under reduced pressure. When the second liquid resin composition 20 is degassed, bubbles can be prevented from being mixed into the artificial marble 100. The supply ports 71 a and 72 a may flow out the high specific gravity liquid resin compositions 21 and 22 while moving on the recess 51. In the case where the bottom surface 51b of the recess is planar, the thickness T2 that is increased by the second liquid resin composition 20 that has entered the recess 51 is not particularly limited, but may be, for example, 1 to 20 mm. The increasing thickness T2 is a thickness obtained by subtracting the thickness T1 corresponding to the first liquid resin composition 10 from the thickness on the bottom surface 51b of the liquid resin compositions 10 and 20. When the second liquid resin composition 20 includes a plurality of liquid resin compositions having different colors, the increasing thickness T2 is a thickness increased by the plurality of liquid resin compositions.
In addition, what is necessary is just to prepare a supply part for every kind of high specific gravity liquid resin composition, when the 2nd liquid resin composition 20 contains several high specific gravity liquid resin composition.

  Although ratio T2 / T1 of thickness T2 by the 2nd liquid resin composition 20 with respect to thickness T1 by the 1st liquid resin composition 10 is not specifically limited, For example, it can be set as 0.2-20. When the ratio T2 / T1 is 0.2 or more (more preferably 2 or more, more preferably 3 or more), a very good pattern is formed by the cured component of the second liquid resin composition 20, which is preferable.

  Since the specific gravity of the second liquid resin composition 20 to be added is larger than the specific gravity of the first liquid resin composition 10, at least a part of the second liquid resin composition 20 is the first as illustrated in FIG. 2. A part of one liquid resin composition 10 is pushed up and settled. A part of the first liquid resin composition 10 floats on the second liquid resin composition 20. In addition, at least a part of the first liquid resin composition 10 in contact with the bottom surface 51b of the recess 51 is usually left in contact with the bottom surface 51b.

(Process 3)
Next, the liquid resin compositions 10 and 20 are cured in a state where a part of the first liquid resin composition 10 floats on the second liquid resin composition 20 in the mold 50. Of the liquid resin compositions 10 and 20, the first liquid resin composition 10 changes to the first curing component 110, and the second liquid resin composition 20 changes to the second curing component 120. When the second liquid resin composition 20 includes a plurality of high specific gravity liquid resin compositions 21 and 22, the high specific gravity liquid resin composition 21 is changed to a high specific gravity curing component 121, and the high specific gravity liquid resin composition 22 is large. It changes to the specific gravity hardening component 122. For example, when the mold 50 is heated to cure the liquid resin compositions 10 and 20, the liquid resin compositions 10 and 20 are cured in the mold 50. Before heating the mold 50, the recess 51 may be closed by aligning a back mold (not shown) with the upper surface of the mold 50. Although the temperature of curing is not specifically limited, For example, it can be set as 30-150 degreeC. The curing time is not particularly limited, and can be, for example, 10 minutes to 1 day. If the curing temperature is increased, the curing time of the liquid resin composition is shortened, and the first liquid resin composition 10 that floats and the second liquid resin composition 20 that settles can be reduced. On the other hand, when the curing temperature is lowered, the curing time of the liquid resin composition becomes longer, and the first liquid resin composition 10 that floats and the second liquid resin composition 20 that settles can be increased. Therefore, the pattern formed on the surface of the artificial marble can be changed by adjusting the curing temperature.

  Since the liquid resin compositions 10 and 20 are cured by curing, the manufacturing process of the artificial marble 100 may be completed by demolding the artificial marble 100 assuming that the artificial marble 100 is formed. In the artificial marble 100 shown in FIG. 1, the portion that is in contact with the bottom surface 51 b of the recess 51 is the front surface 101, and the upper surfaces 51 t of the liquid resin compositions 10 and 20 that are in the recess 51 are the back surface 102. . As illustrated in FIGS. 2A and 2B, the second liquid resin composition 20 which has settled in a state where the cured component 110 of the first liquid resin composition 10 remains in a thin film form on the surface 101. A pattern due to the component 120 appears. On the back surface 102, the cured component 110 of the first liquid resin composition 10 that has floated appears.

  If necessary, after curing, after-curing may be performed in which the artificial marble 100 is removed from the mold and then heated. For example, if the inner surface of the mold 50 has an uneven shape, cracking may occur when the curing of the liquid resin compositions 10 and 20 is completed only within the mold 50. In such a case, if the artificial marble 100 is taken out from the mold 50 and then cured by after-curing, cracking of the artificial marble 100 can be suppressed. Although the temperature of after-curing is not specifically limited, For example, it can be set as 90-160 degreeC, and the temperature higher than the temperature of curing is preferable. Although the time of after-curing is not specifically limited, For example, it can be set as 50 to 180 minutes.

  After demolding and after-curing as necessary, at least one of the front surface 101 and the back surface 102 may be polished. If the thin film of the 1st hardening component 110 is removed by grind | polishing the surface 101, the clear pattern by the 2nd hardening component 120 will appear on the surface 101. FIG. If the 1st hardening component 110 is removed by grind | polishing the back surface 102, the pattern by the 2nd hardening component 120 will become clear in the back surface 102. FIG. Incidentally, in the manufactured artificial marble, the portion in contact with the bottom surface 51b of the recess may be the back surface side, and the upper surface 51t of the liquid resin composition contained in the recess may be the surface side.

  In the artificial marble 100 described above, the liquid resin compositions 10 and 20 are cured in a state where a part of the first liquid resin composition 10 floats on the second liquid resin composition 20 in the mold 50. So it has an unprecedented pattern. Therefore, the present specific example can provide a production method capable of producing an artificial marble having a better pattern.

(Example of the appearance of artificial marble)
Hereinafter, an example of the appearance of the artificial marble due to the components of the liquid resin compositions 10 and 20 will be described.

Example 1. When using a colorless and transparent first liquid resin composition 10 that does not use a filler and a colorant, and a colored second liquid resin composition 20 that uses a filler and, if necessary, a colorant. .
In this case, since the thin film-like first cured component 110 on the surface 101 is colorless and transparent, glossiness is expressed on the surface 101, and as illustrated in FIG. Irregular patterns due to the curing component 120 of the material can be seen through. Thereby, it is possible to form a favorable pattern, and for example, it is possible to express a texture like a natural stone. In particular, when the thickness ratio T2 / T1 is 0.2 or more (more preferably 2 or more, more preferably 3 or more), the appearance of the artificial marble can be further improved.

Example 2. A colored transparent first liquid resin composition 10 that does not use a filler but uses a colorant, and a colored second liquid resin composition 20 that uses a filler and, if necessary, a colorant. When to use.
In this case, glossiness is expressed on the surface 101, and an irregular pattern due to the colored second cured component 120 is seen through the surface 101 through the colored transparent second cured component 120. Thereby, it is possible to form an unprecedented good pattern. In particular, when the thickness ratio T2 / T1 is 0.2 or more (more preferably 2 or more, more preferably 3 or more), the appearance of the artificial marble can be further improved.

Example 3 A colored first liquid resin composition 10 using a filler and, if necessary, a colorant, and a colored second liquid resin composition 20 using a filler and, if necessary, a colorant, are used. When polishing the surface 101. However, the liquid resin compositions 10 and 20 are different from each other.
In this case, as illustrated in FIG. 2A, an irregular mottled pattern due to the first cured component 110 and the second cured component 120 appears on the surface 101. Thereby, it is possible to form a favorable pattern, and for example, it is possible to express a texture like a natural stone. In particular, when the thickness ratio T2 / T1 is 0.2 or more (more preferably 2 or more, more preferably 3 or more), the first curing component 110 is irregularly inserted into the gap between the second curing components 120. For example, it is suitable for expressing a texture like natural stone.

Example 4 A colorless and transparent first liquid resin composition 10 that does not use a filler and a colorant, a colored high specific gravity liquid resin composition 21 that uses a filler and, if necessary, a colorant, a filler, and necessary When using the colored large specific gravity liquid resin composition 22 using a colorant depending on the case. However, the high specific gravity liquid resin compositions 21 and 22 have different colors.
In this case, since the thin film-like first cured component 110 on the surface 101 is colorless and transparent, glossiness is expressed on the surface 101, and as illustrated in FIG. Irregular mottled patterns due to the curing components 121 and 122 of the liquid resin compositions 21 and 22 are seen through. Thereby, it is possible to form a favorable pattern, and for example, it is possible to express a texture like a natural stone. In particular, when the thickness ratio T2 / T1 is 0.2 or more (more preferably 2 or more, more preferably 3 or more), the appearance of the artificial marble can be further improved.

(3) Example:
EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated concretely, this invention is not limited by the following examples. In addition, specific gravity shown in a present Example is specific gravity which measured the hardened | cured material after the liquid resin composition hardened | cured.

[Example 1]
As the mold, a mold having an upper surface opening having a planar bottom-side recess was used. In the polymerizable solution (including the polymer and the polymerizable monomer), the unsaturated polyester resin 6424 (containing an unsaturated polyester in the polymer and a styrene monomer in the polymerizable monomer, etc.) manufactured by Nippon Iupika Co., Ltd. What added the system hardening accelerator was used. Methyl ethyl ketone peroxide was used as the curing agent. Aluminum hydroxide was used as the filler. As the colorant, white toner (white pigment) and blue toner (blue pigment) were used.
First, a white toner was added to 100 parts by weight of the polymerizable solution, and 0.4 parts by weight of a curing agent was further added to prepare a first liquid resin composition having a specific gravity of 1.19. Further, a blue toner is added to 100 parts by weight of the polymerizable solution, a filler is added in the following addition amounts for the test sections 1-2 to 1-5, and 0.4 part by weight of a curing agent is further added. A second liquid resin composition having the following specific gravity was prepared. Test section 1-1 is a comparative example.
Test section 1-1 1-2 1-3 1-4 1-5
Specific gravity of the first liquid resin composition 1.19 1.19 1.19 1.19 1.19
Specific gravity of second liquid resin composition 1.19 1.39 1.53 1.71 1.90
Filler amount (parts by weight) 0 30 80 150 240
For each test section, after pouring the first liquid resin composition into the mold so as to have a thickness T1 = 2 mm, the second liquid resin is put into the mold from above the first liquid resin composition in the mold. The composition was added to a thickness T2 = 8 mm, and the mold was heated at 40 ° C. for 2 hours to produce an artificial marble sample.

[Evaluation of pattern]
Table 1 shows the results of the evaluation of the pattern formed on the sample.

In Comparative Test Section 1-1, only a slight rise of the first liquid resin composition was observed, and only a small amount of sedimentation of the second liquid resin composition was observed. On the surface 101 of the sample in the comparative test section 1-1, only a little pattern due to the second curing component appeared. On the other hand, in the test sections 1-2 to 1-5, many floating of the first liquid resin composition was observed, and much sedimentation of the second liquid resin composition was observed. The surface 101 of the samples in the test sections 1-2 to 1-5 has a thin film-like first cured component, and an irregular pattern of the second cured component is seen through the first cured component. It was. When the surface 101 of the samples in the test sections 1-2 to 1-5 was polished, a clear pattern of the second cured component appeared.

[Example 2]
The same mold and material as in Example 1 were used.
First, a white toner is added to 100 parts by weight of the polymerizable solution, 80 parts by weight of a filler is added, 0.4 parts by weight of a curing agent is further added, and a first liquid resin composition having a specific gravity of 1.53 is obtained. Prepared. Further, a blue toner is added to 100 parts by weight of the polymerizable solution, a filler is added at the following addition amount for the test sections 2-2 to 2-7, and 0.4 part by weight of a curing agent is further added. A second liquid resin composition having the following specific gravity was prepared. Test sections 2-1 to 2-3 are comparative examples.
Test area 2-1 2-2 2-3 2-3 4-4 5-6 6-7
Specific gravity of the first liquid resin composition 1.53 1.53 1.53 1.53 1.53 1.53 1.53
Specific gravity of the second liquid resin composition 1.19 1.39 1.53 1.56 1.59 1.71 1.90
Filler amount (parts by weight) 0 30 80 90 100 150 240
For each test section, after pouring the first liquid resin composition into the mold so as to have a thickness T1 = 2 mm, the second liquid resin is put into the mold from above the first liquid resin composition in the mold. The composition was added to a thickness T2 = 8 mm, and the mold was heated at 40 ° C. for 2 hours to produce an artificial marble sample.

[Evaluation of pattern]
Table 2 shows the results of evaluation of the pattern formed on the sample.

Moreover, the photograph of the cross section of the sample in the comparative test section 2-1 is shown in FIG. 3, the photograph of the cross section of the sample in the comparative test section 2-3 is shown in FIG. 4, and the photograph of the cross section of the sample in the test section 2-6 is shown. FIG. 6 shows a photograph of the cross section of the sample shown in FIG. 5 and in the test section 2-7. 3 to 6, the upper side is the front side, and the lower side is the back side. FIG. 3 shows that the upper first cured component (white) and the lower second cured component (dark color) are substantially separated. FIG. 4 shows that the first cured component (white) slightly floated to the back side. 5 and 6 show that most of the first curing component (white) has floated to the back side.

  In the comparative test sections 2-1 and 2-2, the second liquid resin composition remained substantially floating on the first liquid resin composition. The surface 101 of the samples in the comparative test sections 2-1 and 2-2 showed almost no pattern due to the second cured component even after polishing. In Comparative Test Group 2-3, only a little floating of the first liquid resin composition was observed, and only a little sedimentation of the second liquid resin composition was observed. On the surface 101 of the sample in the comparative test section 2-3, there was little pattern due to the second curing component. On the other hand, in the test sections 2-4 to 2-7, many floating of the first liquid resin composition was observed, and much sedimentation of the second liquid resin composition was observed. The surface 101 of the samples in the test groups 2-4 to 2-7 has a thin film-like first cured component, and an irregular pattern of the second cured component is seen through the first cured component. It was. When the surface 101 of the samples in the test sections 2-4 to 2-7 was polished, a clear pattern of the second cured component appeared.

[Example 3]
The same mold and material as in Example 1 were used.
First, a white toner was added to 100 parts by weight of the polymerizable solution, and 0.4 parts by weight of a curing agent was further added to prepare a first liquid resin composition having a specific gravity of 1.19. In addition, in the test groups 3-2 to 3-4, a styrene monomer is mixed in the original polymerizable solution so that the blending ratio of the unsaturated polyester decreases in the order of the following test groups 3-1 to 3-4. For each test group, a blue toner is added to 100 parts by weight of the polymerizable solution, 150 parts by weight of a filler is added, and 0.4 part by weight of a curing agent is further added, and a second liquid resin composition having the following viscosity is added. Was prepared.
Test area 3-1 3-2 3-3 3-4
Viscosity (Pa · s) of second liquid resin composition 19 9.7 4.4 1.8
For each test section, after pouring the first liquid resin composition into the mold so as to have a thickness T1 = 2 mm, the second liquid resin is put into the mold from above the first liquid resin composition in the mold. The composition was added to a thickness T2 = 8 mm, and the mold was heated at 40 ° C. for 2 hours to produce an artificial marble sample.

[Evaluation of pattern]
Table 3 shows the results of the evaluation of the pattern formed on the sample.

In any of the test sections, a large amount of the first liquid resin composition was observed to float, and a large amount of the second liquid resin composition was precipitated. The surface 101 of the samples of the test sections 3-1 to 3-4 has a thin film-like first cured component, and an irregular pattern of the second cured component is seen through the first cured component. It was. When the surface 101 of the samples in the test sections 3-1 to 3-4 was polished, a clear pattern of the second cured component appeared.

[Example 4]
As the mold, polymer, polymerizable monomer, etc., the same curing agent and filler as in Example 1 were used. As the colorant, white toner (white pigment), blue toner (blue pigment), and black toner (black pigment) were used.
First, a white toner was added to 100 parts by weight of the polymerizable solution, and 0.4 parts by weight of a curing agent was further added to prepare a first liquid resin composition having a specific gravity of 1.19. Further, the following colorant is added to 100 parts by weight of the polymerizable solution, 150 parts by weight of a filler is added, and 0.4 part by weight of a curing agent is further added to form a second liquid resin composition having a specific gravity of 1.71. A product was prepared.
Test area 4-1 4-2
Colorant of second liquid resin composition Blue toner Black toner For each test section, the first liquid resin composition was poured into the mold so that the thickness T1 = 2 mm, and then the first liquid in the mold The second liquid resin composition was added into the mold from above the resin composition so that the thickness T2 = 8 mm, and the mold was heated at 40 ° C. for 2 hours. After demolding, the surface of the artificial marble sample was polished.

[Evaluation of pattern]
Table 4 shows the results of the evaluation of the pattern formed on the sample.

Moreover, the photograph of the surface of the sample in the test section 4-1 is shown in FIG. 7, and the photograph of the surface of the sample in the test section 4-2 is shown in FIG. In these photographs, the white part is the part where the cured component 110 of the first liquid resin composition 10 is visible, and the dark part is the part where the cured component 120 of the second liquid resin composition 20 is visible. is there. On the surface of the polished sample, a streak pattern due to the curing component 110 of the first liquid resin composition 10 is seen in a large pattern due to the curing component 120 of the second liquid resin composition 20, and natural stone A texture like that was expressed.

[Example 5]
In this example, neither the filler nor the colorant is used in the first liquid resin composition, and the second liquid resin composition is divided into two types of high specific gravity liquid resin compositions 21 and 22.
As the mold, polymer, polymerizable monomer, etc., the same curing agent and filler as in Example 1 were used. As the colorant, white toner (white pigment), red toner (red pigment), and black toner (black pigment) were used.
First, 0.4 part by weight of a curing agent was added to 100 parts by weight of the polymerizable solution to prepare a colorless and transparent first liquid resin composition having a specific gravity of 1.19. Further, a white toner is added to 100 parts by weight of the polymerizable solution, 150 parts by weight of a filler is added, and 0.4 part by weight of a curing agent is further added to prepare a high specific gravity liquid resin composition 21 having a specific gravity of 1.71. did. Further, the following colorant is added to 100 parts by weight of the polymerizable solution, 150 parts by weight of a filler is added, 0.4 part by weight of a curing agent is further added, and a high specific gravity liquid resin composition 22 having a specific gravity of 1.71. Was prepared.
Test area 5-1 5-2
Colorant of large specific gravity liquid resin composition 22 Red toner Black toner After pouring the first liquid resin composition into the mold so that the thickness T1 = 2 mm, the first liquid resin composition in the mold Into the mold, equal volume liquid resin compositions 21 and 22 were added in equal amounts so that the thickness T2 = 8 mm, and the mold was heated at 40 ° C. for 2 hours to produce an artificial marble sample.

[Evaluation of pattern]
Table 5 shows the results of the evaluation of the pattern formed on the sample.

Moreover, the photograph of the surface of the sample in the test section 5-1 is shown in FIG. 9, and the photograph of the surface of the sample in the test section 5-2 is shown in FIG. In these photographs, the white portion is the portion where the cured component 121 of the high specific gravity liquid resin composition 21 is visible, and the dark color portion is the portion where the cured component 122 of the large specific gravity liquid resin composition 22 is visible. The surface of the sample has a colorless and transparent first cured component formed in a thin film shape and is glossy. The cured component 121 of the high specific gravity liquid resin compositions 21 and 22 passes through the first cured component. , 122 irregular mottled patterns were seen, expressing a natural stone-like texture.

  Therefore, the first liquid resin composition having a relatively small specific gravity is poured into the mold, and the second liquid resin composition having a relatively large specific gravity is poured into the mold from above the first liquid resin composition in the mold. In addition, when the first liquid resin composition and the second liquid resin composition are cured in a state where a part of the first liquid resin composition floats on the second liquid resin composition in the mold, It was confirmed that an artificial marble having an unprecedented good pattern was obtained.

(4) Conclusion:
As described above, according to the present invention, it is possible to provide a technique or the like that provides a manufacturing method capable of manufacturing an artificial marble having a better pattern according to various aspects. Needless to say, the above-described basic functions and effects can be obtained even with the technology consisting only of the constituent elements according to the independent claims.
In addition, the configurations disclosed in the above-described examples are mutually replaced or the combination is changed, the known technology and the configurations disclosed in the above-described examples are mutually replaced or the combinations are changed. The configuration described above can also be implemented. The present invention includes these configurations and the like.

10: First liquid resin composition,
20 ... Second liquid resin composition, 21, 22 ... Large specific gravity liquid resin composition,
50 ... mould, 51 ... recess, 51b ... bottom surface, 51t ... top surface,
60 ... Supply part of the first liquid resin composition, 60a ... Supply port,
70, 71, 72 ... supply portion of the second liquid resin composition, 70a, 71a, 72a ... supply port,
100 ... artificial marble 101 ... front surface 102 ... back surface,
110, 120, 121, 122 ... a curing component,
T1, T2 ... thickness.

Claims (3)

Pouring the first liquid resin composition into the mold;
Adding a second liquid resin composition having a specific gravity greater than that of the first liquid resin composition into the mold from above the first liquid resin composition in the mold;
Curing the first liquid resin composition and the second liquid resin composition in a state where a part of the first liquid resin composition floats on the second liquid resin composition in the mold. A process for producing artificial marble.   The method for producing artificial marble according to claim 1, wherein the second liquid resin composition includes a plurality of liquid resin compositions having different colors.   The method for producing artificial marble according to claim 1 or 2, wherein the specific gravity of the second liquid resin composition is 0.03 or more larger than the specific gravity of the first liquid resin composition.