Reinforced fiber resin composite material and resin molded body

Abstract

To provide a reinforced fiber resin composite material capable of realizing a resin molded body having excellent heat shielding properties and further to provide a resin molded body having excellent heat shielding properties.SOLUTION: There is provided a reinforced fiber resin composite material which comprises a thermosetting resin, a glass fiber and an infrared reflective pigment. The content of the infrared reflective pigment preferably is 5 mass% or more and 20 mass% or less based on the total mass of the reinforced fiber resin composite material. The infrared reflective pigment preferably has a spectral reflectance of 50% or more at a wavelength of 1500 nm and the maximum value of the spectral reflectance in visible light preferably is 10% or less. The reinforced fiber resin composite material preferably contains one or more selected from the group consisting of an epoxy resin and a vinylester resin as the thermosetting resin. A resin molded body obtained by curing the reinforced fiber resin composite material is suitable as an exterior material for a vehicle.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fiber-reinforced resin composite material and a resin molded article obtained by curing said material. [Background technology]

[0002] Conventionally, various technologies have been proposed for vehicle exterior materials to suppress temperature rise inside the vehicle cabin due to sunlight, etc. For example, Patent Document 1 discloses a coating composition containing a scale-like infrared reflective pigment and a resin. Patent Document 2 discloses a heat shielding film equipped with a white reflective layer containing a white pigment.

[0003] However, in the case of the coating composition and the heat-shielding film, it is difficult to further improve the heat-shielding performance. In the coating composition, when the concentration of the pigment is increased, the viscosity increases, the coating property decreases, and it is difficult to obtain a good film. In addition, according to Patent Document 1, when the thickness of the coating film exceeds 100 μm, coating film defects such as sagging and popping are likely to occur, so it is difficult to increase the absolute amount of the pigment by making the coating film thicker. Furthermore, when trying to increase the coating film thickness by applying multiple coating films, the workability decreases. In addition, in the heat-shielding film, according to Patent Document 2, the thickness of the white reflective layer is preferably 200 μm or less from the viewpoint of maintaining strength, and it is difficult to increase the absolute amount of the pigment by making the reflective layer thicker.

[0004] Meanwhile, fiber-reinforced resin composite materials, which are made by reinforcing thermosetting resins such as vinyl ester resins with carbon fibers as reinforcing fibers, have attracted attention for their light weight and excellent heat resistance and mechanical strength, and are being used in a wide range of structural applications, including the housings and various members of automobiles and aircraft (see, for example, Patent Document 3). For example, a method of heat-compression molding an intermediate material called sheet molding compound (hereinafter sometimes abbreviated as "SMC") is known as a manufacturing method using the fiber-reinforced resin composite material. By heat-compression molding a laminate of multiple sheets of the SMC, a resin molded body with any thickness can be obtained. For example, a resin molded body with a thickness of 500 μm to 5 mm can be used as an exterior material for vehicles. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2017 / 122733 [Patent Document 2] JP 2022-54886 A [Patent Document 3] Patent No. 7298800 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a reinforced fiber resin composite material capable of realizing a resin molded article having excellent heat shielding properties. Further, an object of the present invention is to provide a resin molded article having excellent heat shielding properties. [Means for solving the problem]

[0007] The present inventors have found that a resin molded product having excellent heat shielding properties cannot be obtained from a reinforced fiber resin composite material in which carbon fiber is used as the reinforcing fiber and an infrared reflective pigment is added. As a result of intensive research, the present inventors have found that the carbon fiber absorbs infrared rays, thereby impairing the heat shielding properties of the infrared reflective pigment, and have arrived at the present invention.

[0008] That is, the reinforced fiber resin composite material according to the present invention is characterized by containing a thermosetting resin, glass fibers, and an infrared reflective pigment.

[0009] The resin molded product according to the present invention is characterized by being obtained by curing the above-mentioned fiber-reinforced resin composite material. Effect of the Invention

[0010] According to the present invention, it is possible to provide a reinforced fiber resin composite material capable of realizing a resin molded article having excellent heat shielding properties. Also, according to the present invention, it is possible to provide a resin molded article having excellent heat shielding properties. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a schematic cross-sectional view showing one embodiment of a resin molded body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described. One embodiment of the present invention is a reinforced fiber resin composite material that contains a thermosetting resin, glass fiber, and an infrared reflective pigment. From the viewpoints of workability and ease of handling, the reinforced fiber resin composite material is preferably a sheet molding compound or a prepreg.

[0013] In one embodiment of the present invention, the thermosetting resin contained in the reinforced fiber resin composite material may be any commonly used resin, such as epoxy resin, vinyl ester resin, phenol resin, urea resin, unsaturated polyester resin, melamine resin, polyurethane, silicone resin, acrylic resin, etc. Since a resin molded product with higher strength can be obtained, epoxy resin or vinyl ester resin is preferable. The reinforced fiber resin composite material may contain a resin composition containing the thermosetting resin.

[0014] The resin composition is not particularly limited and can be arbitrarily selected depending on the desired physical properties of the resin molded product, the application, etc. Hereinafter, the epoxy resin composition and the vinyl ester resin composition will be described in detail.

[0015] The epoxy resin composition is a thermosetting resin composition containing an epoxy group-containing compound and a curing agent or a curing accelerator. The epoxy group-containing compound is not particularly limited in its specific structure as long as it has an epoxy group in its molecular structure, and a wide variety of compounds can be used, and one type may be used alone, or two or more types may be used in combination. Among them, the epoxy group-containing compound is preferably a compound having two or more epoxy groups in its molecular structure, since it becomes an epoxy resin composition with excellent curing reaction. The ratio of the compound having two or more epoxy groups in the molecular structure to the entire epoxy group-containing compound is preferably 80% by mass or more, and particularly preferably 90% by mass or more.

[0016] Examples of the epoxy group-containing compound include diglycidyloxybenzene, diglycidyloxynaphthalene, biphenol-type epoxy resins, bisphenol-type epoxy resins, polyglycidyl ethers of aliphatic polyols, novolac-type epoxy resins, alicyclic epoxy resins, glycidylamine-type epoxy resins, heterocyclic epoxy resins, glycidyl ester-type epoxy resins, triphenolmethane-type epoxy resins, phenol or naphthol aralkyl-type epoxy resins, phenylene or naphthylene ether-type epoxy resins, oxolidone-modified epoxy resins, brominated epoxy resins thereof, and epoxy resins obtained by extending these epoxy group-containing compounds with an extender.

[0017] Examples of the biphenol type epoxy resin include biphenol compounds such as biphenol and tetramethylbiphenol, and polyglycidyl ethers of one or more alkylene oxide adducts of these biphenol compounds with epihalohydrin.

[0018] Examples of the bisphenol type epoxy resin include bisphenol compounds such as bisphenol A, bisphenol F, bisphenol S, bisphenol fluorene, and biscresol fluorene, and polyglycidyl ethers of one or more alkylene oxide adducts of these bisphenol compounds with epihalohydrin.

[0019] Examples of the polyglycidyl ether of the aliphatic polyol include polyglycidyl ethers of various aliphatic polyol compounds and one or more of these alkylene oxide adducts with epihalohydrin. Examples of the aliphatic polyol compound include ethylene glycol, propylene glycol, 1,3-propanediol, 2-methylpropanediol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, Examples of the diol compounds include aliphatic diol compounds such as 1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohexane, and 2,2,4-trimethyl-1,3-pentanediol; alicyclic diol compounds such as 2,2-bis(4-hydroxyphenyl)propane; and aliphatic polyol compounds with three or more functional groups such as trimethylolethane, trimethylolpropane, glycerin, hexanetriol, pentaerythritol, ditrimethylolpropane, and dipentaerythritol.

[0020] Examples of the novolac type epoxy resin include novolac resins formed by polyglycidyl etherifying one or more of various phenolic compounds such as phenol, dihydroxybenzene, cresol, xylenol, naphthol, dihydroxynaphthalene, bisphenol, and biphenol with epihalohydrin.

[0021] Examples of the alicyclic epoxy resin include those obtained by hydrogenating the biphenol compounds or bisphenol compounds, and those obtained by polyglycidyl etherifying one or more of the alkylene oxide adducts thereof with epihalohydrin, as well as 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, 1-epoxyethyl-3,4-epoxycyclohexane, and the like.

[0022] Examples of the glycidylamine type epoxy resin include N,N-diglycidylaniline, triglycidylaminophenol, tetraglycidylxylenediamine, and 4,4'-methylenebis[N,N-diglycidylaniline].

[0023] Examples of the heterocyclic epoxy resin include 1,3-diglycidyl-5,5-dimethylhydantoin and triglycidyl isocyanurate.

[0024] Examples of the glycidyl ester type epoxy resin include diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl-p-oxybenzoate, and glycidyl dimerate.

[0025] Examples of the extender for the epoxy resin include the above-mentioned various biphenol compounds and hydrogenated products thereof, the above-mentioned various bisphenol compounds and hydrogenated products thereof, dibasic acid compounds, and acid group-containing polyester resins.

[0026] Among these, the epoxy resin is preferably the bisphenol type epoxy resin, and more preferably a bisphenol type epoxy resin having an epoxy equivalent in the range of 160 to 260 g / equivalent, because it is excellent in strength of the resin molded product and impregnation into glass fiber. The ratio of the bisphenol type epoxy resin to the entire epoxy group-containing compound is preferably 40 mass% or more, more preferably 60 mass% or more, and particularly preferably 70 mass% or more. The ratio is preferably 95 mass% or less, and more preferably 90 mass% or less.

[0027] From the viewpoint of decreasing the viscosity of the epoxy resin, the epoxy resin composition preferably contains the polyglycidyl ether of the aliphatic polyol, more preferably the polyglycidyl ether of an aliphatic polyol having 2 to 6 carbon atoms. The proportion of the polyglycidyl ether of the aliphatic polyol in the entire epoxy group-containing compound is preferably 5% by mass or more, more preferably 10% by mass or more. The proportion is preferably 50% by mass or less, more preferably 35% by mass or less.

[0028] When the bisphenol type epoxy resin and the polyglycidyl ether of the aliphatic polyol are used in combination, the mass ratio of the two (bisphenol type epoxy resin) / (polyglycidyl ether of the aliphatic polyol) is preferably in the range of 60 / 40 to 95 / 5, and more preferably in the range of 70 / 30 to 85 / 15.

[0029] As the curing agent or curing accelerator, various compounds generally used as curing agents or curing accelerators for epoxy group-containing compounds can be used without any particular limitation. The curing agent or curing accelerator may be used alone or in combination of two or more kinds.

[0030] Examples of the curing agent or curing accelerator include amine compounds, amide compounds, acid anhydrides, phenolic hydroxyl group-containing compounds, phosphorus compounds, imidazole compounds, imidazoline compounds, urea compounds, organic acid metal salts, Lewis acids, and amine complex salts.

[0031] Examples of the amine compound include aliphatic amine compounds such as ethylenediamine, tetramethylethylenediamine, diethylenetriamine, hexamethylenediamine, triethylenetetramine, and guanidine derivatives; alicyclic and heterocyclic amine compounds such as piperidine, piperazine, isophoronediamine, and 1,8-diazabicyclo-[5.4.0]-undecene (DBU); aromatic amine compounds such as phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, benzylmethylamine, dimethylbenzylamine, xylylenediamine, and pyridine; and boron trifluoride amine complexes.

[0032] Examples of the amide compound include dicyandiamide and polyamidoamine. Examples of the polyamidoamine include those obtained by reacting an aliphatic dicarboxylic acid such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, or azelaic acid, or a carboxylic acid compound such as a fatty acid or a dimer acid, with an aliphatic polyamine or a polyamine having a polyoxyalkylene chain.

[0033] Examples of the acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0034] Examples of the phenolic hydroxyl group-containing resin include various novolak resins, dicyclopentadiene-phenol addition type resins, phenol or naphthol aralkyl resins, triphenolmethane resins, phenol or naphthol aralkyl resins, phenylene or naphthylene ether resins, and aminotriazine-modified phenol resins.

[0035] Examples of the phosphorus compound include alkyl phosphines such as ethylphosphine and butylphosphine, primary phosphines such as phenylphosphine, dialkyl phosphines such as dimethylphosphine and dipropylphosphine, secondary phosphines such as diphenylphosphine and methylethylphosphine, and tertiary phosphines such as trimethylphosphine, triethylphosphine and triphenylphosphine.

[0036] Examples of the imidazole compound include imidazole, 1-methylimidazole, 2-methylimidazole, 3-methylimidazole, 4-methylimidazole, 5-methylimidazole, 1-ethylimidazole, 2-ethylimidazole, 3-ethylimidazole, 4-ethylimidazole, 5-ethylimidazole, 1-n-propylimidazole, 2-n-propylimidazole, 1-isopropylimidazole, 2 -Isopropylimidazole, 1-n-butylimidazole, 2-n-butylimidazole, 1-isobutylimidazole, 2-isobutylimidazole, 2-undecyl-1H-imidazole, 2-heptadecyl-1H-imidazole, 1,2-dimethylimidazole, 1,3-dimethylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 1-phenylimidazole, 2-phenyl-1H- Imidazole, 4-methyl-2-phenyl-1H-imidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-phenylimidazole Examples of the isocyanuric acid adduct include isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-phenyl-4,5-di(2-cyanoethoxy)methylimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, and 1-benzyl-2-phenylimidazole hydrochloride.

[0037] Examples of the imidazoline compound include 2-methylimidazoline and 2-phenylimidazoline.

[0038] Examples of the urea compound include p-chlorophenyl-N,N-dimethylurea, 3-phenyl-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-N,N-dimethylurea, N-(3-chloro-4-methylphenyl)-N',N'-dimethylurea, and 4,4'-methylenebisphenyldimethylurea.

[0039] Among these, the curing agent or curing accelerator is preferably an amine compound, an amide compound, an imidazole compound, or a urea compound, since it cures quickly and gives a cured product with excellent strength.

[0040] The amount of the curing agent or curing accelerator in the epoxy resin composition is preferably in the range of 0.5 to 1.2 moles of functional group or active hydrogen in the curing agent per mole of epoxy group in the epoxy group-containing compound when using a compound having a functional group that can react with an epoxy group, such as an amine compound, an amide compound, an acid anhydride, or a phenolic hydroxyl group-containing compound. Also, when using a phosphorus compound, an imidazole compound, an imidazoline compound, a urea-based compound, or the like, it is preferable to mix the curing agent or curing accelerator in a ratio of 0.5 to 20 parts by mass per 100 parts by mass of the epoxy group-containing compound.

[0041] The epoxy resin composition may contain other components other than the epoxy group-containing compound and the curing agent or curing accelerator. Examples of other components include curable compounds other than the epoxy group-containing compound, curing agent, or curing accelerator, curing catalysts, water absorbents, thermoplastic resins, inorganic fillers, low shrinkage agents, mold release agents, thickeners, viscosity reducers, pigments, antioxidants, plasticizers, flame retardants, antibacterial agents, ultraviolet stabilizers, reinforcing materials, etc. These other components are added appropriately depending on the desired performance and applications of the sheet molding compound, and the amount of addition is also arbitrary.

[0042] In particular, the epoxy resin composition preferably further contains a polyhydroxy compound and a polyisocyanate compound, since a sheet molding compound having excellent handling properties such as peelability from the carrier film can be obtained. In this case, the total mass of the epoxy group-containing compound, the curing agent or curing accelerator, the polyhydroxy compound, and the polyisocyanate compound in the epoxy resin composition is preferably 80 mass% or more, and particularly preferably 90 mass% or more.

[0043] The polyhydroxy compound is not particularly limited in its specific structure, and a wide variety of compounds can be used as long as it has a plurality of hydroxyl groups in its molecular structure. The polyhydroxy compound may be used alone or in combination of two or more kinds. In this specification, the polyhydroxy compound having an epoxy group is treated as the epoxy group-containing compound.

[0044] Examples of the polyhydroxy compound include aliphatic polyol compounds, dihydroxybenzenes, dihydroxynaphthalenes, trihydroxybenzenes, trihydroxynaphthalenes, triphenol alkanes, biphenol compounds, bisphenol compounds, alicyclic polyol compounds, novolak resins, phenol or naphthol aralkyl resins, phenylene or naphthylene ether resins, and alkylene oxide adducts thereof.

[0045] Examples of the aliphatic polyol compound include ethylene glycol, propylene glycol, 1,3-propanediol, 2-methylpropanediol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, and neopentyl glycol. aliphatic diol compounds such as 1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohexane, and 2,2,4-trimethyl-1,3-pentanediol; alicyclic diol compounds such as 2,2-bis(4-hydroxyphenyl)propane; and aliphatic polyol compounds with three or more functional groups such as trimethylolethane, trimethylolpropane, glycerin, hexanetriol, pentaerythritol, ditrimethylolpropane, and dipentaerythritol.

[0046] Examples of the biphenol compound include biphenol and tetramethylbiphenol.

[0047] Examples of the bisphenol compound include bisphenol A, bisphenol F, bisphenol S, bisphenol fluorene, and biscresol fluorene.

[0048] Examples of the alicyclic polyol compound include cyclohexanediol and hydrogenated biphenol compounds and bisphenol compounds.

[0049] Examples of the novolak type resin include novolak resins made of one or more of various phenolic compounds such as phenol, dihydroxybenzene, cresol, xylenol, naphthol, dihydroxynaphthalene, bisphenol, and biphenol.

[0050] Among them, it is preferable to use a polyhydroxy compound having a hydroxyl equivalent in the range of 125 to 600 g / equivalent, since it is possible to obtain a sheet molding compound having excellent handling properties such as peelability from a carrier film, and it is more preferable that the ratio of polyhydroxy compounds having a hydroxyl equivalent in the range of 125 to 600 g / equivalent to the total polyhydroxy compounds is 70% by mass or more, and it is particularly preferable that the ratio is 80% by mass or more. In addition, the polyhydroxy compound is preferably one having a (poly)alkylene oxide structure in its molecular structure, more preferably an alkylene oxide adduct of the aliphatic polyol compound or the bisphenol compound, and more preferably an aliphatic polyol compound having 2 to 6 carbon atoms. In addition, it is more preferable that the hydroxyl equivalent is in the range of 150 to 400 g / equivalent.

[0051] In addition, the amount of the polyhydroxy compound is preferably 5 parts by mass or more, and more preferably 10 parts by mass or more, and is preferably 50 parts by mass or less, and more preferably 30 parts by mass or less, relative to 100 parts by mass of the epoxy group-containing compound, in order to obtain a sheet molding compound having excellent handleability, such as strength of a resin molded product and peelability from a carrier film.

[0052] The polyisocyanate compound may have any of a wide variety of structures without any particular limitations, so long as it has a plurality of isocyanate groups in its molecular structure. The polyisocyanate compound may be used alone or in combination of two or more. Specific examples include aliphatic diisocyanate compounds such as butane diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and dimer acid diisocyanate; alicyclic diisocyanate compounds such as norbornane diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate; toluene diisocyanate, and xylylene diisocyanate. aromatic diisocyanate compounds such as tetramethylxylylene diisocyanate, tolidine diisocyanate, diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, and polymethylene polyphenyl polyisocyanate; modified products of these isocyanate compounds, such as isocyanurate modified products, biuret modified products, allophanate modified products, carbodiimide modified products, and urethane imine modified products, as well as polyol modified products modified with a polyol having a number average molecular weight of 1,000 or less, such as diethylene glycol or dipropylene glycol.

[0053] Among these, aromatic polyisocyanate compounds or various modified products thereof are preferred because they can provide a sheet molding compound that is excellent in handling properties such as peelability from the carrier film, etc. The isocyanate group content is preferably 15% by mass or more, more preferably 20% by mass or more, and is preferably 40% by mass or less.

[0054] The amount of the polyisocyanate compound added is preferably 0.5 or more, more preferably 0.8 or more, in terms of the mole number of isocyanate groups in the polyisocyanate compound per mole of hydroxyl groups in the polyhydroxy compound, since a sheet molding compound having excellent handling properties such as peelability from a carrier film can be obtained, and is preferably 3.0 or less, more preferably 1.5 or less, and particularly preferably 1.2 or less.

[0055] When the epoxy resin composition contains the polyisocyanate compound or the polyol compound, a urethanization catalyst or a water absorbing agent may be added as necessary. The urethanization catalyst may be used alone or in combination of two or more. Examples of the urethanization catalyst include amine compounds such as triethylamine, dibutylamine, triethylenediamine, and pyridine; phosphorus compounds such as triphenylphosphine and triethylphosphine; organic tin compounds such as dibutyltin dilaurate, octyltin trilaurate, octyltin diacetate, dibutyltin diacetate, and tin octylate; organic zinc compounds such as zinc amine, zinc carboxylate, zinc stearate, and zinc octylate; organic bismuth compounds such as bismuth carboxylate; organic zirconium compounds such as zirconium acetylacetonate and zirconium tetraethanolate; organic aluminum compounds such as aluminum triethoxide; and organic titanium compounds such as titanium tetrabutylate and titanium ethylacetoacetate. Among them, organic zinc compounds and organic bismuth compounds are preferred because they are safer to living organisms and have better storage stability.

[0056] When the urethanization catalyst is used, the amount added is preferably in the range of 0.002 to 1 mass %, more preferably in the range of 0.01 to 0.8 mass %, based on the total mass of the epoxy group-containing compound, the curing agent or curing accelerator, the polyhydroxy compound, and the polyisocyanate compound.

[0057] The water absorbing agent may be used alone or in combination of two or more kinds. Examples of the water absorbing agent include silica gel, activated alumina, and molecular sieves. Among these, molecular sieves are preferred because of their excellent water absorption efficiency. The pore size is preferably in the range of 0.1 to 0.5 nm, and more preferably in the range of 0.2 to 0.4 nm. The particle size is preferably 50 um or less, and more preferably 10 um or less. When the water absorbing agent is used, the amount of the water absorbing agent added is preferably in the range of 0.1 to 5 mass% based on the total mass of the epoxy group-containing compound, the curing agent or curing accelerator, the polyhydroxy compound, and the polyisocyanate compound.

[0058] In order to obtain excellent impregnation ability into glass fibers, the viscosity of the epoxy resin composition at 25°C is preferably 100 mPa·s or more, more preferably 300 mPa·s or more, and is preferably 10,000 mPa·s or less, more preferably 6,000 mPa·s or less. In this specification, the viscosity of the epoxy resin composition is measured within 10 minutes after all the ingredients of the epoxy resin composition are mixed.

[0059] The vinyl ester resin composition is a thermosetting resin composition containing a vinyl ester resin. Examples of vinyl ester resins include those using an epoxy group-containing compound and (meth)acrylic acid as reaction raw materials. One type of vinyl ester resin may be used alone, or two or more types may be used in combination. In this specification, "(meth)acrylic acid" refers to either or both of acrylic acid and methacrylic acid, and "(meth)acrylate" refers to either or both of acrylate and methacrylate.

[0060] The epoxy group-containing compound that is the reaction raw material of the vinyl ester resin may be any of the various compounds exemplified above as those contained in the epoxy resin composition. Among them, the bisphenol type epoxy resin or the epoxy resin obtained by elongating the bisphenol type epoxy resin with an elongating agent is preferred because of its excellent strength of the resin molded product and its impregnation into glass fiber. The epoxy equivalent of the bisphenol type epoxy resin or the epoxy resin obtained by elongating the bisphenol type epoxy resin with an elongating agent is preferably 160 g / equivalent or more, more preferably 170 g / equivalent or more, and is preferably 400 g / equivalent or less, more preferably 380 g / equivalent or less.

[0061] The reaction between the epoxy group-containing compound and (meth)acrylic acid can be carried out by heating at a temperature of about 60 to 140°C in the presence of any esterification catalyst. If necessary, a reaction solvent or a polymerization inhibitor may be added. In addition, the reaction ratio of the epoxy group-containing compound and (meth)acrylic acid is preferably such that the molar ratio of the functional groups of both [carboxy group / epoxy group] is in the range of 0.6 to 1.1 in order to obtain a vinyl ester resin with an excellent balance of performance such as impregnation ability into glass fiber and curing ability. When multiple types of the vinyl ester resin are used in combination, multiple epoxy group-containing compounds may be (meth)acrylated together, or each may be (meth)acrylated separately and mixed.

[0062] The proportion of the vinyl ester resin using the bisphenol-type epoxy resin or the epoxy resin obtained by elongating the bisphenol-type epoxy resin with an elongator as a reaction raw material in the entire vinyl ester resin is preferably 70 mass % or more, more preferably 80 mass % or more, and particularly preferably 90 mass % or more.

[0063] The vinyl ester resin composition may contain other components other than the vinyl ester resin composition. Examples of other components include polymerizable unsaturated group-containing compounds other than the vinyl ester resin, polyisocyanate compounds, curing catalysts, water absorbents, thermoplastic resins, inorganic fillers, shrinkage reducing agents, release agents, thickeners, viscosity reducers, pigments, antioxidants, plasticizers, flame retardants, antibacterial agents, ultraviolet stabilizers, reinforcing materials, etc. These other components are added appropriately according to the desired performance and applications of the sheet molding compound, and the amount of addition is also arbitrary.

[0064] Among them, it is preferable to use a polymerizable unsaturated group-containing compound other than the vinyl ester resin, because it is excellent in strength of the resin molded product and impregnation into glass fiber. The polymerizable unsaturated group-containing compound may be used alone or in combination of two or more. When using a polymerizable unsaturated group-containing compound, the ratio of the polymerizable unsaturated group-containing compound to the total of 100 parts by mass of the thermosetting resin and the polymerizable unsaturated group-containing compound is preferably 15% by mass or more, more preferably 30% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, and particularly preferably 50% by mass or less.

[0065] Examples of the polymerizable unsaturated group-containing compound include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, isotridecyl (meth)acrylate, n-stearyl (meth)acrylate, ethylene glycol (meth)acrylate alkyl ether, propylene glycol Aliphatic mono(meth)acrylate compounds such as chol(meth)acrylate alkyl ether; alicyclic mono(meth)acrylate compounds such as cyclohexyl(meth)acrylate, isobornyl(meth)acrylate, adamantyl mono(meth)acrylate, dicyclopentenyloxyethyl(meth)acrylate, dicyclopentanyl methacrylate; heterocyclic mono(meth)acrylate compounds such as glycidyl(meth)acrylate, tetrahydrofurfuryl acrylate; benzyl(meth)acrylate, phenyl(meth)acrylate, phenyl(meth)acrylate, aromatic ring-containing mono(meth)acrylate compounds such as phenylbenzyl (meth)acrylate, phenoxy (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxyethoxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, phenoxybenzyl (meth)acrylate, benzyl benzyl (meth)acrylate, and phenylphenoxyethyl (meth)acrylate; ) (poly)oxyalkylene-modified mono(meth)acrylate compounds having a polyoxyalkylene chain such as an oxytetramethylene chain introduced therein; lactone-modified mono(meth)acrylate compounds having a (poly)lactone structure introduced into the molecular structure of the various mono(meth)acrylate compounds mentioned above; aliphatic di(meth)acrylate compounds such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, and neopentyl glycol di(meth)acrylate;Alicyclic di(meth)acrylate compounds such as 1,4-cyclohexanedimethanol di(meth)acrylate, norbornane di(meth)acrylate, norbornane dimethanol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, and tricyclodecane dimethanol di(meth)acrylate; aromatic ring-containing di(meth)acrylate compounds such as biphenol di(meth)acrylate and bisphenol di(meth)acrylate; and compounds having (poly)oxyethylene in the molecular structure of the above di(meth)acrylate compounds. polyoxyalkylene-modified di(meth)acrylate compounds having a (poly)oxyalkylene chain such as a propylene chain, a (poly)oxypropylene chain, or a (poly)oxytetramethylene chain introduced therein; lactone-modified di(meth)acrylate compounds having a (poly)lactone structure introduced into the molecular structure of the above-mentioned various di(meth)acrylate compounds; aliphatic tri(meth)acrylate compounds such as trimethylolpropane tri(meth)acrylate and glycerin tri(meth)acrylate; (Poly)oxyalkylene-modified tri(meth)acrylate compounds in which a (poly)oxyalkylene chain such as a (poly)oxyethylene chain, a (poly)oxypropylene chain, or a (poly)oxytetramethylene chain has been introduced into the aliphatic tri(meth)acrylate compound; lactone-modified tri(meth)acrylate compounds in which a (poly)lactone structure has been introduced into the molecular structure of the aliphatic tri(meth)acrylate compound; pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate aliphatic poly(meth)acrylate compounds having 4 or more functional groups, such as tetrafunctional or higher functional poly(meth)acrylates; (poly)oxyalkylene-modified poly(meth)acrylate compounds having 4 or more functional groups in which a (poly)oxyalkylene chain, such as a (poly)oxyethylene chain, a (poly)oxypropylene chain, or a (poly)oxytetramethylene chain, has been introduced into the molecular structure of the aliphatic poly(meth)acrylate compounds; and lactone-modified poly(meth)acrylate compounds having 4 or more functional groups in which a (poly)lactone structure has been introduced into the molecular structure of the aliphatic poly(meth)acrylate compounds.

[0066] Among these, the aromatic ring-containing (meth)acrylate compounds are preferred, and aromatic ring-containing mono(meth)acrylates are more preferred, because they provide excellent strength to resin molded articles and excellent impregnation properties into glass fibers.

[0067] In addition, the vinyl ester resin composition preferably contains a polyisocyanate compound, since it can produce a sheet molding compound that is excellent in handling properties such as peelability from a carrier film. The polyisocyanate compound may be used alone or in combination of two or more. The amount of the polyisocyanate compound added is preferably 5% by mass or more, more preferably 10% by mass or more, and is preferably 40% by mass or less, more preferably 30% by mass or less, based on the total mass of the vinyl ester resin and the polymerizable unsaturated group-containing compound.

[0068] The polyisocyanate compound may be any of the various compounds exemplified as those that may be contained in the epoxy resin composition. Among them, aromatic polyisocyanate compounds or various modified compounds thereof are preferred because they can produce a sheet molding compound that is excellent in handling properties such as peelability from a carrier film. The isocyanate group content is preferably 15% by mass or more, more preferably 20% by mass or more, and is preferably 40% by mass or less.

[0069] The vinyl ester resin composition may contain a polymerization initiator. The polymerization initiator may be a general one without any particular limitation, but is preferably an organic peroxide. Examples of the organic peroxide include diacyl peroxide compounds, peroxyester compounds, hydroperoxide compounds, ketone peroxide compounds, alkyl perester compounds, percarbonate compounds, and peroxyketals. These polymerization initiators may be used alone or in combination of two or more. From the viewpoint of the balance between storage stability and curability, the amount of the polymerization initiator added is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, and more preferably 3% by mass or less, and more preferably 2% by mass or less, based on the total mass of the vinyl ester resin and the polymerizable unsaturated group-containing compound.

[0070] The vinyl ester resin composition may contain a polymerization inhibitor. Examples of the polymerization inhibitor include hydroquinone, trimethylhydroquinone, pt-butylcatechol, t-butylhydroquinone, toluhydroquinone, p-benzoquinone, naphthoquinone, hydroquinone monomethyl ether, phenothiazine, copper naphthenate, and copper chloride. These may be used alone or in combination of two or more. The amount of the polymerization inhibitor added is preferably in the range of 0.01 to 3 mass% based on the total mass of the vinyl ester resin and the polymerizable unsaturated group-containing compound.

[0071] In order to obtain excellent impregnation ability into glass fibers, the viscosity of the vinyl ester resin composition at 25°C is preferably 100 mPa·s or more, more preferably 300 mPa·s or more, and is preferably 10,000 mPa·s or less, more preferably 6,000 mPa·s or less. In this specification, the viscosity of the vinyl ester resin composition is measured within 10 minutes after all the ingredients of the vinyl ester resin composition are mixed.

[0072] As the resin contained in the reinforced fiber resin composite material, in addition to the thermosetting resin, a thermoplastic resin may be used. Examples of the thermoplastic resin include polyamide resin, polyacetal resin, aromatic polyester resin such as polyethylene terephthalate resin, polybutylene terephthalate resin, and polycarbonate resin, polyurethane resin, polyolefin resin such as polypropylene resin and polyethylene resin, polystyrene resin, acrylic resin, polyarylene sulfide resin, and those modified by copolymerization or the like. These may be used alone or in combination of two or more kinds.

[0073] The reinforced fiber resin composite material essentially contains glass fiber and an infrared reflective pigment in addition to the thermosetting resin.

[0074] The reinforced fiber resin composite material contains glass fibers, which ensures the thickness and strength of the resin molding itself. Since glass fibers have lower infrared absorption than carbon fibers, the heat shielding performance of the infrared reflective pigment is not impaired. Furthermore, the glass fibers contained in the reinforced fiber resin composite material suppress the polymerization shrinkage of the thermosetting resin during heat curing, so that the reinforced fiber resin composite material can be obtained with a desired thickness.

[0075] The content of glass fiber is preferably 20% by mass or more based on the total mass of the reinforced fiber resin composite material or the resin molded body from the viewpoint of suppressing polymerization shrinkage of the thermosetting resin and ensuring the strength of the resin molded body. Also, in order to sufficiently impregnate the glass fiber with the thermosetting resin and prevent the occurrence of non-impregnated areas, the content of glass fiber is preferably 60% by mass or less based on the total mass of the reinforced fiber resin composite material or the resin molded body. Furthermore, from the viewpoint of balancing polymerization shrinkage, strength of the resin molded body, and impregnation, the content of glass fiber is more preferably 30% by mass or more and 50% by mass or less.

[0076] Examples of glass fibers include glass fiber aggregates such as chopped glass fiber deposits, chopped glass fiber mats, glass fiber woven fabrics, and glass fiber nonwoven fabrics. The thickness of the glass fiber aggregate may be appropriately set and selected according to the desired thickness of the resin molded body. When ensuring the thickness of the resin molded body using the glass fiber aggregate, the lamination process takes time and effort if there are many layers. Therefore, in order to reduce the number of layers, the thickness of the glass fiber aggregate is preferably, for example, 0.1 mm or more, 1 mm or more, or 2 mm or more. The basis weight of the glass fiber aggregate is 300 g / m 2 More than 350g / m 2 or more than 400g / m 2 It is preferable that the thickness is 1500 g / m or more. 2 Below 1200g / m 2 or less than 1000g / m 2 It is preferable that:

[0077] When an SMC sheet is used as the reinforced fiber resin composite material, the average length of the glass fibers contained in the reinforced fiber resin composite material is preferably 1 mm or more, 3 mm or more, or 5 mm or more in order to ensure the strength of the resin molded body, and is preferably 50 mm or less, 25 mm or less, or 15 mm or less in order to ensure fluidity in a mold during resin molding.

[0078] The average length of the glass fibers contained in the reinforced fiber resin composite material is measured by the following method. Approximately 20 mg of glass fiber is weighed out into a polyethylene cup and rubbed against the wall of the cup with a metal spatula to break it down. The glass fiber adhering to the wall of the cup is pressed onto one side of a weak adhesive double-sided tape to attach it to the tape. The other adhesive side of the double-sided tape to which the glass fiber has been attached is attached flat onto a white plastic sheet to create a sheet for microscopic observation. This sheet for microscopic observation is observed with the optical microscope equipment described below, and optical images are obtained. The distance obtained using the two-point distance measurement tool of the image analysis software described below is regarded as the length of the fiber. 100 glass fibers are randomly selected, their lengths are measured and recorded, and the number average length is calculated. As the optical microscope device, for example, a digital microscope VR-3200 manufactured by KEYENCE Corporation can be used, and the magnification of the microscope can be, for example, 12 to 40 times depending on the length of the glass fiber. As the analysis software, for example, software VR-3000 G2 observation application Ver2.4.0.115 (plane measurement-two-point distance measurement tool) manufactured by KEYENCE Corporation can be used.

[0079] The infrared reflective pigment is a pigment capable of reflecting light having a wavelength of 780 to 2500 nm. The type, shape, size, amount of the infrared reflective pigment, etc. can be appropriately selected depending on the purpose.

[0080] Examples of the infrared reflective pigment include inorganic pigments such as composite oxides of metals containing at least one metal element selected from the group consisting of zinc, chromium, titanium, manganese, antimony, iron, bismuth, tantalum, niobium, zirconium, hafnium, tungsten, aluminum, cobalt, and nickel. As the infrared reflective pigment, one type may be used alone, or two or more types may be used in combination. In order to reliably ensure the heat shielding effect, the infrared reflective pigment preferably has a spectral reflectance of 50% or more for light with a wavelength of 1500 nm. In addition, in order to prevent the reflection of visible light from causing dazzling to the surroundings, the infrared reflective pigment preferably has a maximum spectral reflectance of visible light of 10% or less. This means that the maximum spectral reflectance of light in the entire wavelength range of visible light (380 nm to 780 nm) is 10% or less. Examples of such infrared reflective pigments include chromium iron oxide, manganese bismuth oxide, calcium / titanium / manganese oxide ((Ca,Ti,Mn)O 3 ) and the like. Furthermore, it is particularly preferable to use iron chromium oxide because of its excellent black color, surface smoothness, and dispersibility in thermosetting resins. The spectral reflectance can be measured, for example, by the method described below.

[0081] The infrared reflective pigment may have any shape, such as a spherical shape, a flake shape, a porous shape, etc. A shape close to a sphere is preferable because it allows a high loading amount in the reinforced fiber resin composite material and the resin molded body. In addition, the infrared reflective pigment is preferably a flake shape such as a scale shape, a plate shape, or a flat shape because it allows infrared reflective performance to be ensured with a small loading amount.

[0082] The average particle size of the infrared reflective pigment is preferably in the range of 10 nm to 1 μm from the viewpoints of improving dispersibility, hiding property, etc. The average particle size can be obtained, for example, by photographing the infrared reflective pigment with an electron microscope, randomly selecting 50 of the pigment particles present within the viewing angle, measuring the particle size, and calculating the arithmetic mean of the results. Note that, when the pigment is not spherical, the maximum particle size is measured.

[0083] The content of the infrared reflective pigment is preferably 1% by mass or more and 3% by mass or more based on the total mass of the reinforced fiber resin composite material or resin molded body from the viewpoint of ensuring heat shielding performance. Also, the content of the infrared reflective pigment is preferably 50% by mass or less and 30% by mass or less from the viewpoint of ensuring surface smoothness of the resin molded body. And, the content of the infrared reflective pigment is preferably 5% by mass or more and 20% by mass or less, and more preferably 8% by mass or more and 15% by mass or less, from the viewpoint of achieving both heat shielding performance and surface smoothness of the molded body.

[0084] In one embodiment of the present invention, the reinforced fiber resin composite material and the resin molding may further contain other components, such as fillers (excluding glass fibers and infrared reflective pigments), low shrinkage agents, release agents, thickeners, viscosity reducers, pigments, antioxidants, plasticizers, flame retardants, antibacterial agents, UV stabilizers, reinforcing materials, and photocuring agents.

[0085] In one embodiment of the present invention, the reinforced fiber resin composite material and the resin molded body may further contain other fibers made of a material different from the above-mentioned glass fiber, from the viewpoint of easily ensuring the thickness and strength of the resin molded body. The other fibers are preferably ones having low infrared reflectivity, similar to the glass fibers. The other fibers may be fiber aggregates such as woven fabrics, nonwoven fabrics, cut fiber bundle mats, and paper sheets. As the fibers, ceramic fibers, fibers derived from natural stones, organic fibers, and the like can be used. Examples of the ceramic fibers include alumina fibers, zirconia fibers, and boron fibers. Examples of the fibers derived from natural stones include basalt fibers. Examples of the organic fibers include polyester fibers, polypropylene fibers, polyamide fibers, polyarylene sulfide fibers, and natural organic fibers.

[0086] 1 is a schematic cross-sectional view showing one embodiment of a resin molded body. As shown in FIG. 1, a resin molded body 1 according to one embodiment contains a thermosetting resin 2, glass fiber 3, and an infrared reflective pigment 4.

[0087] The thickness of the resin molded body can be appropriately set depending on the application. It is preferable that the thickness is 500 μm or more and 5 mm or less, because this ensures the strength of the resin molded body, contains a sufficient amount of infrared reflective pigment, and ensures excellent heat shielding performance.

[0088] The shape of the resin molded body is arbitrary, and may be a sheet-like shape or a three-dimensional shape such as a box. In one embodiment, the resin molded body can be produced by curing a sheet-like reinforced fiber resin composite material. From the viewpoint of ease of work and ease of handling, the sheet-like reinforced fiber resin composite material is preferably a sheet molding compound or a prepreg.

[0089] The resin molded body of this embodiment can be obtained, for example, by a production method including a step (A) of producing a reinforced fiber resin composite material and a step (B) of producing a resin molded body.

[0090] <Resin molding material manufacturing process (A)> In step (A), for example, a mixture of a thermosetting resin composition and an infrared reflective pigment is impregnated into a glass fiber assembly by means of pressure or the like to obtain a fiber-reinforced resin composite material. The fiber-reinforced resin composite material thus obtained is called an SMC (sheet molding compound) sheet or prepreg.

[0091] <Resin Molded Body Manufacturing Process (B)> In step (B), the reinforced fiber resin composite material obtained in step (A) is cured to form a resin molded product. More specifically, a reinforced fiber resin composite material having a projected area equal to or smaller than the cavity thickness of the mold cavity is placed in the mold cavity. At this time, a plurality of sheets of the reinforced fiber resin composite material may be laminated depending on the thickness of the desired resin molded product. Next, the mold is clamped to pressurize the reinforced fiber resin composite material, thereby filling the cavity with the reinforced fiber resin composite material to form the product. There is no particular limitation on the molding method. For example, the thermosetting resin contained in the reinforced fiber resin composite material is crosslinked by applying heat and pressure using a heated press machine, and a resin molded product is obtained.

[0092] A method for producing a resin molded product using a sheet-shaped fiber-reinforced resin composite material will be described below.

[0093] First, a resin composition for use in a reinforced fiber resin composite material is prepared by stirring and mixing a thermosetting resin, an infrared reflective pigment, a curing agent, and the like. Next, the resin composition is applied onto a carrier film, and a glass fiber layer is placed thereon. Another set of carrier films coated with the resin composition is prepared, and the sets are laminated in the order of carrier film / resin composition / glass fiber layer / resin composition / carrier film, and the resin composition is impregnated into the glass fiber layer using a pressure roll or the like to prepare a reinforced fiber resin composite material. After pressing with a pressure roll or the like, the set may be allowed to stand for 10 hours or more in a temperature range of room temperature (e.g., 25°C) to about 50°C for aging.

[0094] For example, the obtained reinforced fiber resin composite material is placed in a mold and cured by heating and pressurization to produce a resin molded product. At this time, the number of layers of the reinforced fiber resin composite material and the height of the mold cavity can be adjusted to obtain a resin molded product of a desired thickness.

[0095] The resin molded body of the present embodiment has excellent appearance, bending strength, bending modulus, etc., and also has excellent heat insulation properties, and therefore can be suitably used for automobile parts, railway vehicle parts, aerospace equipment parts, ship parts, housing equipment parts, light vehicle parts, construction and civil engineering parts, etc., and is particularly suitable as a vehicle exterior material such as an automobile bonnet hood, door, roof, etc. EXAMPLES

[0096] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0097] <Preparation of Thermosetting Resin Composition> In Examples 1 to 7 and Comparative Example 1, 1200 g of a thermosetting resin composition was prepared with the blending ratios (mass ratios) shown in Tables 1 and 2. First, a vinyl ester resin paste was prepared by stirring and mixing a bisphenol A type vinyl ester resin (Exdoma (registered trademark) manufactured by DIC Materials Co., Ltd.) and phenoxyethyl methacrylate (flash point 120°C) as the polymerizable unsaturated group-containing compound. Next, a polyisocyanate (Lupranate (registered trademark) MI manufactured by BASF INOAC Polyurethanes Co., Ltd., NCO group content 33.3 or more) was added and mixed well at room temperature, and then any one of the infrared reflective pigments a to c described below was further added and mixed. Furthermore, a polymerization initiator (Kayacarvon (registered trademark) AIC-75 manufactured by Kayaku Akzo Co., Ltd., organic peroxide) and parabenzoquinone as a polymerization inhibitor were added and stirred well at room temperature to obtain a thermosetting resin composition. The following infrared reflective pigments a to c were used. Infrared reflective pigment a: Sun Chemical, Sicopal (registered trademark) Black L 0095, iron chromium oxide, reflectance of light with a wavelength of 1500 nm (hereinafter referred to as "infrared reflectance"): 75%, maximum reflectance of light in the entire wavelength range of 380 to 780 nm (hereinafter referred to as "maximum visible light reflectance"): 5.1% Infrared reflective pigment b: Ishihara Sangyo Kaisha, Ltd., Type Black SG-101, (Ca,Ti,Mn)O 3 , Infrared reflectance: 67%, Maximum visible light reflectance: 8.5% Infrared reflective pigment c: Ishihara Sangyo Kaisha, Ltd., Typek R-820, titanium dioxide, infrared reflectance: 82%, maximum visible light reflectance: 90%

[0098] <Preparation of fiber-reinforced resin composite material> In Examples 1 to 7, 600 g of the obtained thermosetting resin composition was divided into approximately half, and each half was applied to a 100 cm square area of ​​a polypropylene casting film. Next, 800 g of glass fibers (PB-549, manufactured by Nittobo Co., Ltd., weight per unit area: 4.8 g / m) chopped to a length of 2 cm was uniformly spread as reinforcing fibers on the applied surface of the resin composition to form a glass fiber layer. Similarly, half of the remaining thermosetting resin composition was applied to a 100 cm square area of ​​a polypropylene casting film, and the applied surface was overlapped so as to be in contact with the glass fiber layer to obtain a laminate. Next, the laminate was pressed with a hand roller to sufficiently impregnate the glass fiber layer, and aged at room temperature for 24 hours or more to obtain a reinforced fiber resin composite material (2000 g / m) which is a sheet molding compound provided with casting films on both sides. 2 The obtained fiber-reinforced resin composite material had a glass fiber content of 40 mass % based on the total mass of the thermosetting resin composition. In Comparative Example 1, a reinforced fiber resin composite material (2000 g / m) was prepared in the same manner as in Example 3, except that 800 g of carbon fiber (manufactured by Toray Industries, Inc., basis weight 3800 g / m) cut to a length of 2 cm was used instead of the glass fiber as the reinforcing fiber. 2The obtained fiber-reinforced resin composite material had a carbon fiber content of 40 mass % based on the total mass of the thermosetting resin composition.

[0099] <Preparation of resin molded body> In Examples 1 to 7 and Comparative Example 1, the obtained sheet molding compound with the processing film was cut into 30 cm square pieces, and then the processing film was peeled off. The 30 cm square sheet molding compound was heated and compressed in a mold to produce a resin molded body. The mold was composed of a convex upper mold and a concave lower mold, and had a cavity of 30 cm length and 30 cm width, and the height of the cavity was adjustable by a spacer. After placing a laminate of two 30 cm square sheet molding compounds in the center of the mold, in which the cavity height was adjusted to 2.0 mm, the mold was closed, and the temperature of the upper mold was set to 140°C, the temperature of the lower mold was set to 150°C, and pressure was applied for 10 minutes under the condition of 92t to produce a resin molded body with a thickness of 2.0 mm.

[0100] <Evaluation of blister generation amount> The surface of the obtained resin molded article was visually observed, and the amount of blisters on the surface of the resin molded article was evaluated based on the following evaluation criteria. The results are shown in Tables 1 and 2. <<Evaluation>> 〇:Resin molding surface 1m 2 The number of bubbles generated per unit is 5 or less. △:Resin molding surface 1m 2 The amount of bubbles generated per unit is 6 to 9. ×: Resin molded body surface 1m 2 The number of bubbles generated per unit is 10 or more.

[0101] <Measurement of bending strength and bending modulus of molded product> Test pieces were cut out from the obtained resin molded body, and a three-point bending test was carried out in accordance with JIS K 7074 to measure the bending strength and bending modulus of elasticity. The results are shown in Tables 1 and 2. <<Evaluation (bending strength)>> ○: 250MPa or more. ×: Less than 250 MPa. <<Evaluation (bending strength)>> 〇: 17GPa or higher. ×: Less than 17 GPa.

[0102] <Measurement of infrared reflectance> A test piece measuring 50 mm in length, 50 mm in width and 2 mm in thickness was cut out from the obtained resin molded body, and the spectral reflectance of infrared rays at a wavelength of 1500 nm was measured using a SolidSpec-3700DUV (Shimadzu Corporation, double beam system). The measurement was carried out using an integrating sphere, and not only the regular reflection component but also the reflection component due to diffuse light was measured. The infrared reflectance of the resin molded body was evaluated based on the following evaluation criteria. The higher the reflectance, the better the heat shielding performance. The results are shown in Tables 1 and 2. <<Evaluation>> ◯: Infrared reflectance is 70% or more. △: Infrared reflectance is 50% or more and less than 70%. ×: Infrared reflectance is less than 50%.

[0103] <Measurement of visible light reflectance> A test piece measuring 50 mm in length, 50 mm in width and 2 mm in thickness was cut out from the obtained resin molded body, and the spectral reflectance of visible light over the entire wavelength range of 380 to 780 nm was measured using a SolidSpec-3700DUV (Shimadzu Corporation, double beam system). The measurement was performed using an integrating sphere, and the measurement included not only the regular reflection component but also the reflection component due to diffuse light. The maximum value of the reflectance of visible light over the entire wavelength range of 380 to 780 nm was evaluated based on the following evaluation criteria. The results are shown in Tables 1 and 2. <<Evaluation>> ◯: The maximum visible light reflectance is 10% or less. △: The maximum visible light reflectance exceeds 10%.

[0104] [Table 1]

[0105] [Table 2]

[0106] From Tables 1 and 2, when comparing the resin molding of Example 3, which contains glass fiber and infrared reflective pigment, with the resin molding of Comparative Example 1, which contains carbon fiber instead of glass fiber and the same amount of infrared reflective pigment as Example 3, it can be seen that Example 3 has high infrared reflective performance and excellent heat shielding properties, whereas Comparative Example 1 has low infrared reflective performance and inferior heat shielding properties.

[0107] Comparing the resin moldings of Examples 1 to 5, the higher the content of the infrared reflective pigment, the higher the infrared reflective performance and the improved heat shielding properties, but the greater the amount of blistering and the lower the surface smoothness. Considering the balance between infrared reflective performance and the amount of blistering, it can be seen that, among Examples 1 to 5, Examples 2 to 4 are preferable, and Example 3 is the most excellent.

[0108] Comparing the resin molded bodies of Examples 3, 6, and 7, it can be seen that, from the viewpoints of obtaining an excellent heat shielding effect and reducing glare in the surroundings, iron chromium oxide (infrared reflective pigment a) and oxide of calcium / titanium / manganese (infrared reflective pigment b) are preferable as infrared reflective pigments. Furthermore, it can be seen that iron chromium oxide is more preferable from the viewpoints of reducing the amount of blistering and obtaining surface smoothness. [Explanation of symbols]

[0109] 1...resin molded body, 2...thermosetting resin, 3...glass fiber, 4...infrared reflective pigment.

Claims

1. A fiber-reinforced resin composite material comprising a thermosetting resin, glass fibers, and an infrared reflective pigment.

2. 2. The reinforced fiber resin composite material according to claim 1, wherein the content of the infrared reflective pigment is 5% by mass or more and 20% by mass or less, based on the total mass of the reinforced fiber resin composite material.

3. 3. The reinforced fiber resin composite material according to claim 1, wherein the infrared reflective pigment has a spectral reflectance of 50% or more at a wavelength of 1,500 nm.

4. 4. The fiber-reinforced resin composite material according to claim 3, wherein the maximum value of the spectral reflectance of the infrared reflective pigment for visible light is 10% or less.

5. 3. The reinforced fiber resin composite material according to claim 1, wherein the thermosetting resin is at least one selected from the group consisting of epoxy resins and vinyl ester resins.

6. 3. A resin molded product obtained by curing the reinforced fiber resin composite material according to claim 1.

7. 7. The resin molding according to claim 6, which is used as an exterior material for a vehicle.

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