Forming material, formed product, and artificial marble

Abstract

The present invention provides a molding material, which is characterized in that it is a molding material having, as essential raw materials, a polymer component (A) containing an unsaturated polyester (a1), an unsaturated monomer (B), a curing agent (C), a thickening agent (D), an inorganic filler (E), and glass fibers (F) having a fiber length of 1.5 to 6 mm. The content of the unsaturated monomer (B) is 4 to 10% by mass, the weight average molecular weight of the unsaturated polyester (a1) is 5000 to 40000, and the unsaturated dibasic acid in the raw materials of the unsaturated polyester (a1) is 15 to 50% by mass. Since a molded article having excellent transparency, gloss, and image clarity can be obtained, this molding material can be suitably used for residential equipment members such as bathroom members.

Description

Technical Field

[0001] The present invention relates to a molding material, a molded article, and artificial marble. Background Art

[0002] Conventionally, resin compositions based on thermosetting resins such as unsaturated polyester resins and vinyl ester resins are molded and cured to manufacture artificial marble products such as bathroom cabinets, washstands, and bathtubs.

[0003] Among such compositions, as a composition suitable for artificial marble having excellent transparency, an unsaturated polyester resin composition mixed with an unsaturated polyester, a copolymerizable monomer, crosslinkable polymer particles, and an inorganic filler has been proposed (for example, refer to Patent Document 1).

[0004] However, in applications that require higher designability, the molded articles obtained from such compositions have problems of insufficient transparency and image clarity (Japanese: writeability).

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Laid-Open No. 9-302009 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] The problem to be solved by the present invention is to provide a molding material, a molded article thereof, and artificial marble that can obtain a molded article having a low shrinkage rate, excellent transparency, gloss, and image clarity.

[0010] Means for Solving the Problems

[0011] The present inventors conducted in-depth research to solve the above problems and found that a molding material containing specific polymer components, unsaturated monomers, curing agents, thickeners, inorganic fillers, and glass fibers as essential raw materials can obtain a molded article and artificial marble having a low shrinkage rate, excellent transparency, gloss, and image clarity, thereby completing the present invention.

[0012] That is, the present invention relates to a molding material, which is characterized in that it is a molding material having, as essential raw materials, a polymer component (A) containing an unsaturated polyester (a1), an unsaturated monomer (B), a curing agent (C), a thickening agent (D), an inorganic filler (E), and glass fibers (F) having a fiber length of 1.5 to 6 mm. The content rate of the unsaturated monomer (B) is 4 to 10% by mass, the weight-average molecular weight of the unsaturated polyester (a1) is 5,000 to 40,000, and the unsaturated dibasic acid in the raw materials of the unsaturated polyester (a1) is 15 to 50% by mass.

[0013] Advantages of the Invention

[0014] Since the molding material of the present invention can obtain molded articles having excellent transparency, gloss, and image clarity, it can be suitably used for residential equipment components such as bathroom components (bathtubs, waterproof trays, bathroom cabinets, walls), washbasin cabinets, storage cabinets, and kitchen sinks. Detailed Embodiments

[0015] The molding material of the present invention is a molding material having, as essential raw materials, a polymer component (A) containing an unsaturated polyester (a1), an unsaturated monomer (B), a curing agent (C), a thickening agent (D), an inorganic filler (E), and glass fibers (F) having a fiber length of 1.5 to 6 mm. The content rate of the unsaturated monomer (B) is 4 to 10% by mass, the weight-average molecular weight of the unsaturated polyester (a1) is 5,000 to 40,000, and the unsaturated dibasic acid in the raw materials of the unsaturated polyester (a1) is 15 to 50% by mass.

[0016] The unsaturated polyester (a1) is obtained by reacting a polybasic acid containing an unsaturated polybasic acid with a polyol.

[0017] Examples of the unsaturated polybasic acid include unsaturated dibasic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, and itaconic anhydride. Among them, maleic acid, maleic anhydride, and fumaric acid are preferred in terms of excellent strength, hot water resistance, toughness, high gloss, high image clarity, and transparency of the molded article. It should be noted that these unsaturated polybasic acids can be used alone or in combination of two or more.

[0018] As the polybasic acid, examples of the saturated polybasic acid that can be used in combination with the unsaturated polybasic acid include phthalic acid, phthalic anhydride, halogenated phthalic anhydride, isophthalic acid, terephthalic acid, hexahydrophthalic acid, hexahydrophthalic anhydride, hexahydroterephthalic acid, hexahydroisophthalic acid, tetrahydrophthalic acid, tetrahydrophthalic anhydride, tetrahydroterephthalic acid, tetrahydroisophthalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, sebacic acid, 1,12-dodecanedioic acid, cyclohexanedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic anhydride, 4,4'-biphenyldicarboxylic acid and other saturated dibasic acids. Among them, from the aspects of excellent strength, hot water resistance, toughness, high gloss, high image clarity and transparency of the molded article, isophthalic acid, terephthalic acid, phthalic acid and phthalic anhydride are preferred. It should be noted that these saturated polybasic acids can be used alone or in combination of two or more.

[0019] As the polyhydric alcohol, examples include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 2-methyl-1,3-propanediol, 1,3-butanediol, 1,6-hexanediol, neopentyl glycol, hydrogenated bisphenol A, 1,4-butanediol, adducts of bisphenol A with propylene oxide or ethylene oxide, 1,2,3,4-tetrahydroxybutane, glycerin, trimethylolpropane, 1,3-propanediol, 1,2-cyclohexanediol (Japanese: 1,2-シクロヘキサングリコール), 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, p-xylene glycol (Japanese: パラキシレングリコール), bicyclohexyl-4,4'-diol, 2,6-decahydronaphthalenediol, 2,7-decahydronaphthalenediol, etc. Among them, from the aspects of excellent strength, water resistance, hot water resistance, toughness, high gloss and high image clarity of the molded article, propylene glycol, neopentyl glycol and hydrogenated bisphenol A are preferred. It should be noted that these polyhydric alcohols can be used alone or in combination of two or more.

[0020] In the present invention, the unsaturated dibasic acid in the raw materials of the unsaturated polyester (a1) is 15 to 50% by mass, and from the aspect of further improving low shrinkage, it is preferably 15 to 35% by mass. It should be noted that in the present invention, the unsaturated dibasic acid includes unsaturated dibasic anhydride. In addition, the mass% of the unsaturated dibasic acid is the value obtained by the following formula.

[0021] "Mass% of the unsaturated dibasic acid in the raw materials of the unsaturated polyester (a1)"

[0022] = 100 × "Mass of the unsaturated dibasic acid in the raw materials constituting the unsaturated polyester" / "Total mass of the raw materials constituting the unsaturated polyester"

[0023] The weight average molecular weight of the unsaturated polyester (a1) is 5,000 to 40,000. However, from the aspects of further improving the glass fiber impregnation property and kneadability after adding a thickener, and obtaining a viscosity more suitable for formability and further improving the appearance of the molded product, it is preferably 7,000 to 35,000, and more preferably 8,000 to 30,000. It should be noted that the weight average molecular weight in the present invention is a value obtained by polystyrene conversion based on the measurement by gel permeation chromatography (hereinafter simply referred to as "GPC").

[0024] Regarding the solid content acid value of the unsaturated polyester (a1), from the aspects of slow initial thickening behavior, further improving the glass fiber impregnation property and kneadability after adding a thickener, and obtaining a viscosity more suitable for molding, and further improving the appearance of the molded product, it is preferably 20 to 40 mgKOH / g. It should be noted that the acid value in the present invention is a value obtained by using the measurement method according to JIS K6901 (2018) 5.3.2.

[0025] The present invention contains the unsaturated polyester (a1) as a polymer component, but other polymer components such as vinyl ester (a2) can be used in combination.

[0026] The vinyl ester (a2) can be obtained by the reaction of an epoxy resin and (meth)acrylic acid.

[0027] Examples of the epoxy resin include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol fluorene type epoxy resins, bisphenol type epoxy resins such as bis(m-cresol)fluorene type, phenol novolac type epoxy resins, cresol novolac type epoxy resins, oxazolidone-modified epoxy resins, glycidyl ethers of phenols such as brominated epoxy resins of these resins, diglycidyl ether of dipropylene glycol, triglycidyl ether of trimethylolpropane, diglycidyl ether of alkylene oxide adduct of bisphenol A, diglycidyl ether of hydrogenated bisphenol A, etc., glycidyl ethers of polyhydric alcohols, alicyclic epoxy resins such as 3,4-epoxy-6-methylcyclohexylmethyl 3,4-epoxy-6-methylcyclohexanecarboxylate, 1-epoxyethyl-3,4-epoxycyclohexane, glycidyl esters such as diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl p-hydroxybenzoate, glycidyl ester of dimer acid, glycidyl amines such as tetraglycidyl diaminodiphenylmethane, tetraglycidyl metaxylylenediamine, triglycidyl p-aminophenol, N,N-diglycidylaniline, heterocyclic epoxy resins such as 1,3-diglycidyl-5,5-dimethylhydantoin, triglycidyl isocyanurate, etc. Among them, from the viewpoint of further improving the balance of fluidity during molding, strength, transparency, and gloss of the molding material, bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferred. It should be noted that these epoxy resins can be used alone or in combination of two or more.

[0028] Regarding the epoxy equivalent of the epoxy resin, from the viewpoint of further improving the toughness of the molded product, it is preferably in the range of 220 to 470.

[0029] Regarding the unsaturated polyester (a1) in the polymer component (A), from the viewpoint of the balance of low shrinkage, transparency, gloss, and image clarity, it is preferably in the range of 50 to 100% by mass, more preferably in the range of 60 to 100% by mass.

[0030] Regarding the vinyl ester (a2) in the polymer component (A), from the viewpoint of the balance of low shrinkage, transparency, gloss, and image clarity, it is preferably in the range of 0 to 50% by mass, more preferably in the range of 0 to 40% by mass.

[0031] Examples of the unsaturated monomer (B) include styrene, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate alkyl ether, polypropylene glycol (meth)acrylate alkyl ether, 2-ethylhexyl methacrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, isotridecyl (meth)acrylate, n-stearyl (meth)acrylate, tetrahydrofurfuryl methacrylate, isobornyl (meth)acrylate, and dicyclopentadienyloxyethyl (meth)acrylate. , dicyclopentyl methacrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate and other monofunctional (meth) acrylate compounds; ethylene glycol di(meth) acrylate, propylene glycol di(meth) acrylate, 1,4-butanediol di(meth) acrylate, 1,3-butanediol di(meth) acrylate, neopentyl glycol di(meth) acrylate, 1,6-hexanediol di(meth) acrylate, bisphenol di(meth) acrylate, 1,4-cyclohexanedimethanol di(meth) acrylate and other di(meth) acrylate compounds; vinyl toluene, α-methylstyrene, diallyl phthalate, divinylbenzene, etc., among them, styrene is preferred from the perspective of better heat resistance, water resistance, chemical resistance and transparency of the molded product. It should be noted that these unsaturated monomers can be used alone or in combination of two or more.

[0032] The mass ratio (A / B) of the polymer component (A) to the unsaturated monomer (B) is preferably in the range of 80 / 20 to 60 / 40, more preferably in the range of 75 / 25 to 65 / 35, from the viewpoint of the balance between low shrinkage and transparency, gloss, and image clarity.

[0033] The refractive index of the cured product of the resin composition containing the polymer component (A) and the unsaturated monomer (B) is preferably 1.54 to 1.59 from the viewpoint of further improving the transparency of the molded article.

[0034] The curing agent (C) is not particularly limited, but preferably an organic peroxide, for example, a diacyl peroxide compound, a peroxyester compound, a hydroperoxide compound, a ketone peroxide compound (Japanese: ケトンパーオキサイド compound), an alkyl peroxyester compound, a peroxycarbonate compound, a peroxyketal, etc., which can be appropriately selected according to the molding conditions. It should be noted that these curing agents (C) can be used alone or in combination of two or more.

[0035] For the curing agent (C), relative to 100 parts by mass of the total amount of the polymer component (A) and the unsaturated monomer (B), it is preferably 0.3 to 5 parts by mass, more preferably 0.5 to 3 parts by mass.

[0036] Examples of the thickening agent (D) include metal oxides such as magnesium oxide, magnesium hydroxide, calcium oxide, and calcium hydroxide, metal hydroxides, isocyanate compounds, etc. From the aspect of further improving the balance between the handleability and formability of the molding material such as peelability and touch feeling, magnesium oxide is preferred. It should be noted that these thickening agents (D) can be used alone or in combination of two or more.

[0037] For the thickening agent (D), from the aspect of further improving the fluidity of the molding material in the mold, relative to 100 parts by mass of the total amount of the polymer component (A) and the unsaturated monomer (B), it is preferably 0.3 to 5 parts by mass, more preferably 0.5 to 2.5 parts by mass.

[0038] Examples of the inorganic filler (E) include glass powder, glass chopped fiber, aluminum hydroxide, calcium carbonate, magnesium carbonate, barium sulfate, mica, talc, kaolin, clay, silica, silica sand, gypsum, hollow microspheres, alumina, gypsum stone, titanium oxide, etc. These inorganic filler materials (E) can be used alone or in combination of two or more.

[0039] For the inorganic filler (E), from the aspect of further improving the appearance and smoothness of the molded product, relative to 100 parts by mass of the total amount of the polymer component (A) and the unsaturated monomer (B), it is preferably 150 to 400 parts by mass, more preferably 200 to 350 parts by mass, and further preferably 250 to 350 parts by mass.

[0040] For the average particle size of the inorganic filler (E), from the aspect of further improving the gloss and image clarity of the molded product, it is preferably 18 μm or less, more preferably 13 μm or less. It should be noted that the average particle size is a value measured by the dynamic light scattering method (manufactured by Otsuka Electronics Co., Ltd., "Dynamic Light Scattering Photometer DLS - 8000 series").

[0041] For the refractive index of the inorganic filler (E), from the aspect of further improving the transparency of the molded product, it is preferably 1.54 to 1.58.

[0042] As the glass fiber (F), glass fibers with a fiber length of 1.5 to 6 mm are used. However, from the aspect of further improving the gloss and image clarity of the molded product, glass fibers with a fiber length of 1.5 to 3 mm are more preferred.

[0043] As the filament diameter of the glass fiber (F), from the aspect of further improving the gloss and image clarity of the molded article, it is preferably 5 to 15 μm.

[0044] For the glass fiber (F) in the molding material, from the aspect of further improving the gloss and image clarity of the molded article, it is preferably 1 to 17% by mass, more preferably 1 to 12% by mass.

[0045] The molding material of the present invention uses the polymer component (A), the unsaturated monomer (B), the curing agent (C), the thickener (D), the inorganic filler (E), and the glass fiber (F) as essential raw materials. However, in order to obtain a molded article with a low shrinkage rate, excellent transparency, gloss, and image clarity, it is important that the content rate of the unsaturated monomer is in the range of 4 to 10% by mass.

[0046] In the molding material, various additives such as a low shrinkage agent, a polymerization inhibitor, a coloring agent, an ultraviolet absorber, a thickening inhibitor, an antioxidant, a flame retardant, a surfactant, a water repellent, and an oil repellent can be contained as components other than the above essential components.

[0047] Regarding the content rate of the low shrinkage agent such as crosslinked polystyrene in the molding material, from the aspect of further improving the transparency of the molded article, it is preferably 5% by mass or less in the total amount of the resin and the low shrinkage agent components.

[0048] For the molding material of the present invention, from the aspect of further improving the handleability and moldability as a molding material, it is preferably a bulk molding compound (BMC).

[0049] As a method for manufacturing the BMC, a method of mixing the polymer component (A), the unsaturated monomer (B), the curing agent (C), the thickener (D), the inorganic filler (E), the glass fiber (F), and, if necessary, a low shrinkage agent, an internal mold release agent, etc. using a mixer such as a normal roll, a Banbury mixer, a planetary mixer, a kneader, or an extruder can be mentioned.

[0050] The artificial marble of the present invention can be obtained from the molding material. From the aspect of further improving the handleability and moldability as a molding material, as its molding method, a hot compression molding method of BMC is preferred.

[0051] As the heat compression molding method, for example, the following manufacturing method can be used. That is, a prescribed amount of a molding material such as BMC is metered and put into a mold preheated to 100 to 180°C, clamped by a compression molding machine, the molding material is shaped, and a molding pressure of 1 to 20 MPa is maintained to cure the molding material. Thereafter, the molded product is taken out to obtain artificial marble. In this case, the following manufacturing method is preferred. That is, in a mold having a shear edge, at a mold temperature of 110 to 160°C, a molding pressure of 5 to 15 MPa is maintained for a prescribed time of 1 to 2 minutes per 1 mm thickness of the artificial marble for heat compression molding.

[0052] Due to its excellent transparency, gloss, and image clarity, the artificial marble of the present invention can be suitably used for bathroom components (bathtubs, waterproof pans, bathroom cabinets, walls), washbasin cabinets, kitchen cabinets, kitchen sinks and other residential equipment components, walls, floors and other building components, etc.

[0053] Examples

[0054] Specific examples are given below to explain the present invention in more detail. It should be noted that the acid value of the resin is the value measured in accordance with JIS K6901 (2018) 5.3.2, and the weight average molecular weight is the value measured under the following GPC measurement conditions.

[0055] [GPC Measurement Conditions]

[0056] Measurement device: High-speed GPC device ("HLC-8220GPC" manufactured by Tosoh Corporation)

[0057] Chromatographic columns: The following chromatographic columns manufactured by Tosoh Corporation are used in series.

[0058] "TSKgel G5000" (7.8 mm I.D. × 30 cm) × 1 piece

[0059] "TSKgel G4000" (7.8 mm I.D. × 30 cm) × 1 piece

[0060] "TSKgel G3000" (7.8 mm I.D. × 30 cm) × 1 piece

[0061] "TSKgel G2000" (7.8 mm I.D. × 30 cm) × 1 piece

[0062] Detector: RI (differential refractometer)

[0063] Column temperature: 40°C

[0064] Eluent: Tetrahydrofuran (THF)

[0065] Flow rate: 1.0 mL / min

[0066] Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 4 mg / mL)

[0067] Standard sample: A standard curve was prepared using the following monodisperse polystyrene.

[0068] (Monodisperse polystyrene)

[0069] "TSKgel Standard Polystyrene A-500" manufactured by Tosoh Corporation

[0070] "TSKgel Standard Polystyrene A-1000" manufactured by Tosoh Corporation

[0071] "TSKgel Standard Polystyrene A-2500" manufactured by Tosoh Corporation

[0072] "TSKgel Standard Polystyrene A-5000" manufactured by Tosoh Corporation

[0073] "TSKgel Standard Polystyrene F-1" manufactured by Tosoh Corporation

[0074] "TSKgel Standard Polystyrene F-2" manufactured by Tosoh Corporation

[0075] "TSKgel Standard Polystyrene F-4" manufactured by Tosoh Corporation

[0076] "TSKgel Standard Polystyrene F-10" manufactured by Tosoh Corporation

[0077] "TSKgel Standard Polystyrene F-20" manufactured by Tosoh Corporation

[0078] "TSKgel Standard Polystyrene F-40" manufactured by Tosoh Corporation

[0079] "TSKgel Standard Polystyrene F-80" manufactured by Tosoh Corporation

[0080] "TSKgel Standard Polystyrene F-128" manufactured by Tosoh Corporation

[0081] "TSKgel Standard Polystyrene F-288" manufactured by Tosoh Corporation

[0082] "TSKgel Standard Polystyrene F-550" manufactured by Tosoh Corporation

[0083] (Synthesis Example 1: Synthesis of Unsaturated Polyester Resin (1))

[0084] Into a 2 L glass flask equipped with a nitrogen inlet tube, a thermometer, a reflux condenser, and a stirrer, 208 parts by mass of neopentyl glycol, 53 parts by mass of propylene glycol, 264 parts by mass of hydrogenated bisphenol A, and 290 parts by mass of isophthalic acid were charged, and heating was started under a nitrogen stream. At an internal temperature of 215 °C, a dehydration condensation reaction was carried out by a conventional method. When the acid value of the solid component was 5 (mgKOH / g), it was cooled to 190 °C. Then, 196 parts by mass of maleic acid was added, and the dehydration condensation reaction was continued. When the acid value of the solid component was 29 (mgKOH / g), 0.4 parts by mass of methylhydroquinone was added. The unsaturated polyester (a1-1) was dissolved in styrene monomer to a concentration of 70% by mass to obtain an unsaturated polyester resin (1). The weight average molecular weight of the unsaturated polyester (a1-1) was 10,000, and the unsaturated dibasic acid in the raw materials was 19% by mass.

[0085] (Synthesis Example 2: Synthesis of Unsaturated Polyester Resin (2))

[0086] Into a 2 L glass flask equipped with a nitrogen inlet tube, a thermometer, a reflux condenser, and a stirrer, 231 parts by mass of neopentyl glycol, 123 parts by mass of propylene glycol, and 144 parts by mass of isophthalic acid were charged, and heating was started under a nitrogen stream. At an internal temperature of 215 °C, a dehydration condensation reaction was carried out by a conventional method. When the acid value of the solid component was 2 (mgKOH / g), it was cooled to 140 °C. Then, 169 parts by mass of hydrogenated bisphenol A and 344 parts by mass of maleic anhydride were added, and the internal temperature was raised to 205 °C to carry out a dehydration condensation reaction. When the acid value of the solid component was 29 (mgKOH / g), 0.4 parts by mass of methylhydroquinone was added. The unsaturated polyester (a1-2) was dissolved in styrene monomer to a concentration of 70% by mass to obtain an unsaturated polyester resin (2). The weight average molecular weight of the unsaturated polyester (a1-2) was 10,000, and the unsaturated dibasic acid in the raw materials was 34% by mass.

[0087] (Synthesis Example 3: Synthesis of Unsaturated Polyester Resin (3))

[0088] Into a 2 L glass flask equipped with a nitrogen inlet tube, a thermometer, a reflux condenser, and a stirrer, 213 parts by mass of neopentyl glycol, 239 parts by mass of propylene glycol, 111 parts by mass of phthalic acid, 83 parts by mass of isophthalic acid, and 368 parts by mass of maleic anhydride were charged, and heating was started under a nitrogen stream. At an internal temperature of 215 °C, a dehydration condensation reaction was carried out by a conventional method. When the acid value of the solid component was 26 (mgKOH / g), 0.4 parts by mass of methylhydroquinone was added. The unsaturated polyester (a1-3) was dissolved in styrene monomer to a concentration of 70% by mass to obtain an unsaturated polyester resin (3). The weight average molecular weight of the unsaturated polyester (a1-3) was 28,000, and the unsaturated dibasic acid in the raw materials was 36% by mass.

[0089] (Synthesis Example 4: Synthesis of Unsaturated Polyester Resin (R1))

[0090] Into a 2 L glass flask equipped with a nitrogen inlet tube, thermometer, reflux condenser, and stirrer, 479 parts by mass of propylene glycol and 588 parts by mass of fumaric acid were charged, and heating was started under a nitrogen stream. At an internal temperature of 200 °C, a dehydration condensation reaction was carried out by a conventional method. When the acid value of the solid content was 29 (mgKOH / g), 0.4 part by mass of methylhydroquinone was added. The unsaturated polyester (Ra1-1) was dissolved in styrene monomer to a concentration of 70% by mass to obtain an unsaturated polyester resin (R1). The weight-average molecular weight of the unsaturated polyester (Ra1-1) was 15,000, and the unsaturated dibasic acid in the raw materials was 55% by mass.

[0091] (Synthesis Example 5: Synthesis of Unsaturated Polyester Resin (R2))

[0092] Into a 2 L glass flask equipped with a nitrogen inlet tube, thermometer, reflux condenser, and stirrer, 422 parts by mass of dicyclopentadiene (Japanese: ジシクロペンタジエン), 36 parts by mass of phthalic acid, 290 parts by mass of maleic acid, and 67 parts by mass of water were charged, and heating was started under a nitrogen stream. The reaction was carried out at 130 °C. When the acid value of the solid content was 230 (mgKOH / g), 20 parts by mass of ethylene glycol and 161 parts by mass of diethylene glycol were added, and the temperature was raised to 205 °C. A dehydration condensation reaction was carried out by a conventional method. When the acid value of the solid content was 12 (mgKOH / g), 0.4 part by mass of methylhydroquinone was added. The unsaturated polyester (R2) was dissolved in styrene monomer to a concentration of 70% by mass to obtain an unsaturated polyester resin (R2). The weight-average molecular weight of the unsaturated polyester (Ra1-2) was 4,000, and the unsaturated dibasic acid in the raw materials was 29% by mass.

[0093] (Synthesis Example 6: Synthesis of Vinyl Ester Resin (1))

[0094] Into a 2 L flask equipped with a nitrogen inlet tube, a thermometer, and a stirrer, 246 parts by mass of an epoxy resin (“EPICLON 860-C” manufactured by DIC Corporation, bisphenol A type epoxy resin, epoxy equivalent 240), 750 parts by mass of an epoxy resin (“EPICLON 1050” manufactured by DIC Corporation, bisphenol A type epoxy resin, epoxy equivalent 470), 214 parts by mass of methacrylic acid, and 0.42 parts by mass of dibutylhydroxytoluene were added. While flowing a gas mixture of nitrogen and air in a 1:1 ratio, the temperature was raised to 100 °C. 0.97 parts by mass of 2-methylimidazole was added thereto, and the temperature was raised to 110 °C, followed by reaction. When the acid value of the solid content was 6 (mgKOH / g) or less, 0.48 parts by mass of methylhydroquinone was added, and vinyl ester (a2-1) was dissolved in styrene monomer to a concentration of 70 mass%, obtaining vinyl ester resin (1). The epoxy equivalent of the epoxy resin of this vinyl ester (a2-1) was 380.

[0095] (Example 1: Manufacture and evaluation of molding material (1))

[0096] 100 parts by mass of unsaturated polyester resin (1), 1.2 parts by mass of a curing agent (“PERHEXA HC” manufactured by NOF Corporation), 270 parts by mass of an inorganic filler (glass powder (“CF0017-05C06” manufactured by Nippon FRIT Co., Ltd., average particle size 6 - 7 μm; hereinafter abbreviated as “inorganic filler (E-1)”).), 2 parts by mass of an internal mold release agent (zinc stearate), 1.3 parts by mass of a thickening agent (magnesium oxide), and glass fiber (“chopped strand CS2PE-905S” manufactured by Nitto Boseki Co., Ltd., fiber length 1.5 mm, filament diameter 10 μm; hereinafter abbreviated as “glass fiber (F-1)”) were blended so that the fiber content was 6 mass%, and after kneading with a planetary mixer, it was cured at 40 °C for 24 hours to obtain molding material (1) as BMC.

[0097] [Production of artificial marble]

[0098] Compression molding was carried out under the following conditions to obtain artificial marble (1) in the form of a 300 mm × 300 mm × 7 mm flat plate.

[0099] Molding temperature: 130 °C (molded product surface), 115 °C (back surface)

[0100] Molding pressure: 10 MPa

[0101] Pressing time: 480 seconds

[0102] [Evaluation of shrinkage]

[0103] For the artificial marble (1) obtained by the above operations, the dimensions of 6 pieces at 25°C (6 locations where the mold dimensions are known) were measured, and the shrinkage rate of each piece was calculated based on the ratio to the mold dimensions. The average value was set as the shrinkage rate of the artificial marble (1), and the shrinkage property was evaluated using the following criteria.

[0104] ◎: The shrinkage rate is less than 0.3%.

[0105] ○: The shrinkage rate is 0.3 or more and less than 0.35.

[0106] △: The shrinkage rate is 0.35 or more and less than 0.39.

[0107] ×: The shrinkage rate is 0.39 or more.

[0108] [Evaluation of transparency]

[0109] For the artificial marble (1) obtained by the above operations, the total light transmittance was measured using a turbidimeter "NDH5000" manufactured by Nippon Denshoku Industries Co., Ltd., and the transparency was evaluated using the following criteria.

[0110] ◎: The total light transmittance is 25% or more.

[0111] ○: The total light transmittance is 20% or more and less than 25%.

[0112] △: The total light transmittance is 15% or more and less than 20%.

[0113] ×: The total light transmittance is less than 15%.

[0114] [Evaluation of gloss]

[0115] For the artificial marble (1) obtained by the above operations, the reflectance at an incident angle of 20° from 0 to 2000 GU was measured using "BYK Gardnermicro-TRI-gloss" manufactured by BYK Co., Ltd., and the obtained value was set as the 20° gloss value, and the gloss was evaluated using the following criteria.

[0116] ◎: The 20° gloss value is 80 or more.

[0117] ○: The 20° gloss value is 75 or more and less than 80.

[0118] △: The 20° gloss value is 70 or more and less than 75.

[0119] ×: The 20° gloss value is less than 70.

[0120] [Evaluation of image clarity]

[0121] The image clarity (DOI) of the molded product (1) obtained by the above operation was measured using "Rhopoint IQ-s" manufactured by Konica Minolta Co., Ltd., and the image clarity was evaluated according to the following criteria.

[0122] ◎: DOI is 90 or above

[0123] ○: DOI is 80 or more and less than 90

[0124] △: DOI is 70 or more and less than 80

[0125] ×: DOI less than 70

[0126] (Example 2: Production and evaluation of molding material (2))

[0127] A molding material (2) and a molding product (2) were prepared in the same manner as in Example 1 except that 270 parts by mass of the inorganic filler (E-1) used in Example 1 was changed to 320 parts by mass, and various properties were evaluated.

[0128] (Example 3: Production and evaluation of molding material (3))

[0129] A molding material (3) and a molding product (3) were prepared in the same manner as in Example 1, except that 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 was changed to 75 parts by mass of the unsaturated polyester resin (1) and 25 parts by mass of the vinyl ester resin (1), and 270 parts by mass of the inorganic filler (E-1) was changed to 320 parts by mass. Various properties were evaluated.

[0130] (Example 4: Production and Evaluation of Forming Material (4))

[0131] A molding material (4) and a molding product (4) were prepared in the same manner as in Example 1, except that 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 was replaced by 75 parts by mass of the unsaturated polyester resin (1) and 25 parts by mass of the vinyl ester resin (1), and 270 parts by mass of the inorganic filler (E-1) was replaced by 245 parts by mass of the inorganic filler (E-1) and 75 parts by mass of aluminum hydroxide ("CW-308B" manufactured by Sumitomo Chemical Co., Ltd., with an average particle size of 10 μm; hereinafter abbreviated as "inorganic filler (E-2)"), and various properties were evaluated.

[0132] (Example 5: Production and evaluation of molding material (5))

[0133] Except for changing 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 to 100 parts by mass of the unsaturated polyester resin (2) and changing 270 parts by mass of the inorganic filler (E-1) to 320 parts by mass, the molding material (5) and the molded product (5) were produced in the same manner as in Example 1, and various properties were evaluated.

[0134] (Example 6: Manufacture and evaluation of molding material (6))

[0135] Except for changing 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 to 100 parts by mass of the unsaturated polyester resin (3) and changing 270 parts by mass of the inorganic filler (E-1) to 320 parts by mass, the molding material (6) and the molded product (6) were produced in the same manner as in Example 1, and various properties were evaluated.

[0136] (Example 7: Manufacture and evaluation of molding material (7))

[0137] Except for changing 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 to 95 parts by mass of the unsaturated polyester resin (1) and 5 parts by mass of a low shrinkage agent (“Stafiloid GS-102R” manufactured by Aica Kogyo Co., Ltd., crosslinked polystyrene resin powder, surface-treated product of aluminum hydroxide) and changing 270 parts by mass of the inorganic filler (E-1) to 320 parts by mass, the molding material (7) and the molded product (7) were produced in the same manner as in Example 1, and various properties were evaluated.

[0138] (Example 8: Manufacture and evaluation of molding material (8))

[0139] Except for changing the glass fiber (F-1) used in Example 1 to a glass fiber (“chopped strand CS6PE-908” manufactured by Nitto Boseki Co., Ltd., fiber length 6 mm, filament diameter 13 μm; hereinafter simply referred to as “glass fiber (F-2)”), the molding material (8) and the molded product (8) were produced in the same manner as in Example 1, and various properties were evaluated.

[0140] (Example 9: Manufacture and evaluation of molding material (9))

[0141] Except for changing 6% by mass of the glass fiber (F-1) used in Example 1 to 10% by mass, the molding material (9) and the molded product (9) were produced in the same manner as in Example 1, and various properties were evaluated.

[0142] (Comparative Example 1: Manufacture and evaluation of molding material (R1))

[0143] Except that 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 was changed to 67.5 parts by mass of the unsaturated polyester resin (1) and 32.5 parts by mass of the styrene monomer, and 270 parts by mass of the inorganic filler (E-1) was changed to 320 parts by mass, the molding material (R1) and the molded product (R1) were produced in the same manner as in Example 1, and various properties were evaluated.

[0144] (Comparative Example 2: Production and Evaluation of Molding Material (R2))

[0145] Except that 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 was changed to 100 parts by mass of the unsaturated polyester resin (R1), and 270 parts by mass of the inorganic filler (E-1) was changed to 320 parts by mass, the molding material (R2) and the molded product (R2) were produced in the same manner as in Example 1, and various properties were evaluated.

[0146] (Comparative Example 3: Production and Evaluation of Molding Material (R3))

[0147] Except that 100 parts by mass of the unsaturated polyester resin (1) used in Example 1 was changed to 100 parts by mass of the unsaturated polyester resin (R2), 1.3 parts by mass of the thickener was changed to 2 parts by mass, and 270 parts by mass of the inorganic filler (E-1) was changed to 320 parts by mass, the molding material (R3) was produced in the same manner as in Example 1. However, the thickening was insufficient and molding was not possible.

[0148] The compositions and evaluation results of the molding materials (1) to (9) obtained by the above operations are shown in Tables 1 and 2.

[0149] [Table 1]

[0150]

[0151] [Table 2]

[0152]

[0153] The compositions and evaluation results of the molding materials (R1) to (R3) obtained by the above operations are shown in Table 2.

[0154] [Table 3]

[0155]

[0156] It was confirmed that the molding materials of Examples 1 to 9 had a low shrinkage rate during molding, and the obtained molded products had excellent transparency, gloss, and image clarity.

[0157] Comparative Example 1 is an example in which the content rate of the unsaturated monomer in the molding material is higher than 10% by mass which is the upper limit of the present invention, and it was confirmed that the shrinkage rate during molding was high.

[0158] Comparative Example 2 is an example in which the content of the unsaturated dibasic acid in the raw material of the unsaturated polyester resin is higher than 50% by mass, which is the upper limit of the present invention, and it was confirmed that the shrinkage rate during molding was high.

[0159] Comparative Example 3 is an example in which the weight average molecular weight of the unsaturated polyester resin is less than 5,000, which is the lower limit of the present invention. The thickening of the molding material was not sufficient enough to enable molding.

Claims

1. A shaping material, characterized in that, The molding material uses, as essential raw materials, a polymer component A containing an unsaturated polyester a1, an unsaturated monomer B, a curing agent C, a thickener D, an inorganic filler E, and glass fibers F having a fiber length of 1.5 mm to 6 mm. The content of the unsaturated monomer B is 4% by mass to 10% by mass. The weight-average molecular weight of the unsaturated polyester a1 is 5,000 to 40,000, the acid value of the solid content of the unsaturated polyester a1 is 20 mg KOH / g to 40 mg KOH / g, and the unsaturated dibasic acid in the raw materials of the unsaturated polyester a1 is 15% by mass to 19% by mass. The average particle size of the inorganic filler E is 6 μm or more and 18 μm or less.

2. The molding material according to claim 1, wherein with respect to a total of 100 parts by mass of the polymer component A and the unsaturated monomer B, the inorganic filler E is 150 parts by mass to 400 parts by mass.

3. The molding material according to claim 1 or 2, wherein the thickener D is magnesium oxide.

4. An artificial marble using the molding material according to any one of claims 1 to 3.

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