JP6182013B2 - Thermal barrier composition, thermal barrier member, and thermal barrier coating - Google Patents

Description

  The present invention relates to a thermal barrier composition, a thermal barrier member, and a thermal barrier coating.

  In recent years, the global warming phenomenon has heightened awareness of the environment, and a new energy system that does not generate greenhouse gases such as carbon dioxide is attracting attention. Environmentally friendly renewable energy such as solar cell power generation and wind power generation does not emit carbon dioxide and other gases that are said to induce global warming, and therefore, research and development are being actively conducted as clean energy. In particular, solar cells and solar thermal power generation are attracting attention because they are excellent in safety and ease of handling.

  In solar cells, the light receiving surface is protected by a protective cover made of glass, weather-resistant resin film, etc., but the protective cover is contaminated with dust during long-term use, resulting in a decrease in light transmittance. There is a problem that the energy conversion efficiency decreases. In addition, crystalline silicon and polycrystalline silicon type solar cells have a problem that power generation efficiency decreases as the temperature increases as a characteristic of silicon.

  For example, Patent Document 1 discloses a technique in which silica, an infrared absorbing material, and polymer emulsion particles are mixed. A thermal composition is disclosed.

JP 2011-181636 A

  However, from the viewpoint of blending stability of the infrared absorbing material, those described in the above documents have room for improvement.

  Then, this invention is made | formed in view of the said problem, and provides the thermal-insulation coating film which is excellent in antifouling property and a total light transmittance, and can suppress the temperature rise of a solar cell by an infrared thermal-insulation effect. An object of the present invention is to provide a coating composition that can be prepared and has excellent blending stability, a heat shielding member having a coating film obtained from the coating composition, and a thermal coating film.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by using polymer particles containing an infrared absorbing material in the core, and have reached the present invention.

That is, the present invention is as follows.
[1]
Including colloidal silica (A) and polymer particles (B),
The polymer particles (B), a core comprising an infrared absorbing material (b1), and covering the core, have a, a shell comprising a polymer (b2),
The polymer particles (B) have a silanol group and / or an amide group on the surface,
The colloidal silica (A) has a number average particle diameter of 1 nm to 400 nm,
The infrared absorbing material (b1) contains a composite of zinc oxide and antimony oxide, and the number average particle diameter is 5 nm to 200 nm.
Thermal barrier composition.
[2]
The heat-shielding composition according to [1] , further comprising a hydrolyzable silicon compound (C).
[3]
[1] or [ 1] wherein the polymer (b2) comprises a polymer of a hydrolyzable silicon compound (b3) and a vinyl monomer (b4) having a secondary and / or tertiary amide group. 2] .
[4]
In the presence of water and an emulsifier, the polymer particles (B) have the infrared absorber (b1), the hydrolyzable silicon compound (b3), and the vinyl unit having a secondary and / or tertiary amide group. mer (b4) and comprises polymer particles obtained by polymerizing, items [1] to thermal barrier composition according to any one of [3].
[5]
Comprising a base material is coated with a thermal barrier composition according to any one of items [1] to [4] on the substrate, and a thermal barrier coating formed by drying, heat shield .
[6]
The heat shield member according to [5] above, which is a solar cell protective member.
[7]
Polymer particles (B) comprising a core containing an infrared absorbing material (b1), and a shell covering the core and containing a polymer (b2);
Possess the polymer particles (B) silanol groups on the surface and / or amide groups and covalent and / or hydrogen bonds with bound colloidal silica (A), a,
The colloidal silica (A) has a number average particle diameter of 1 nm to 400 nm,
The infrared absorbing material (b1) contains a composite of zinc oxide and antimony oxide, and the number average particle diameter is 5 nm to 200 nm.
Thermal barrier coating.

  The present invention provides a thermal barrier coating film that is excellent in antifouling property and total light transmittance and that can suppress the temperature rise of the solar cell due to an infrared thermal barrier effect, and furthermore, a coating composition having excellent blending stability, It aims at providing the thermal-insulation member which has the thermal-insulation coating film obtained from a coating-film composition, and the thermal-insulation coating film obtained from the said coating-film composition.

  Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as “the present embodiment”) will be described in detail. The following embodiments are exemplifications for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be implemented with appropriate modifications within the scope of the gist thereof.

[Heat shielding composition]
The thermal barrier composition according to this embodiment is
Including colloidal silica (A) and polymer particles (B),
The polymer particles (B) have a core containing the infrared absorbing material (b1) and a shell covering the core and containing the polymer (b2).

  Colloidal silica (A) is considered to act as a curing agent for component (B) by interacting with polymer particles (B). Although it does not specifically limit as the said interaction, For example, the hydroxyl group which (A) component generally has, and the hydroxyl group, carboxyl group, amide group, amino group, and / or ether group which (B) component may have, Examples thereof include a hydrogen bond, a condensation (chemical bond) between a hydroxyl group that the component (A) generally has and a functional group that the polymer (b2) constituting the component (B) may have.

  Thereby, the thermal insulation composition excellent in the mixing | blending stability of an infrared absorber can be obtained. In addition, it is possible to obtain a thermal barrier composition that provides a thermal barrier coating film that is excellent in antifouling property and total light transmittance and that can suppress the temperature rise of the solar cell by the infrared thermal barrier effect.

[Colloidal silica (A)]
Colloidal silica (A) is a dispersion of silica water or a water-soluble solvent having silicon dioxide as a basic unit. The number average particle diameter of the colloidal silica (A) is preferably 1 nm to 400 nm, more preferably 1 nm to 200 nm, still more preferably 1 nm to 100 nm, and still more preferably 5 nm to 30 nm. When the number average particle diameter is 1 nm or more, the storage stability of the heat shielding composition tends to be better. Moreover, it exists in the tendency for the transparency of the heat-shielding coating film obtained from a heat-shielding composition to become more favorable because a number average particle diameter is 100 nm or less. The colloidal silica (A) may be acidic or basic in the state of water or a dispersion of a water-soluble solvent. The pH of the colloidal silica (A) can be appropriately selected according to the pH range in which the aqueous dispersion of the component (B) contained in the heat shielding composition can stably exist.

  Although it does not specifically limit as acidic colloidal silica which uses water as a dispersion medium, For example, Nissan Chemical Industries Co., Ltd. Snowtex (trademark) -O, Snowtex OS, Snowtex-OL, Asahi Denka is a commercial item. Adelite (trademark) AT-20Q manufactured by Kogyo Co., Ltd., Clevosol (trademark) 20H12, Clevosol 30CAL25 manufactured by Clariant Japan Co., Ltd. and the like can be mentioned.

  The basic colloidal silica using water as a dispersion medium is not particularly limited, and examples thereof include colloidal silica stabilized by addition of alkali metal ions, ammonium ions, or amines. Although it does not specifically limit as such colloidal silica, More specifically, as a commercial item, Nissan Chemical Industries Co., Ltd. Snowtex-20, Snowtex-30, Snowtex-C, Snowtex-C30, Snowtex-CM40, Snowtex-N, Snowtex-N30, Snowtex-K, Snowtex-XL, Snowtex-YL, Snowtex-ZL, Snowtex PS-M, Snowtex PS-L, Asahi Denka Adelite AT-20, Adelite AT-30, Adelite AT-30N, Adelite AT-30N, Adelite AT-30A, Adelite AT-30A, Adelite AT-40, Adelite AT-50 manufactured by Kogyo Co., Ltd., Clariant Japan ( Kurebosol 30R9, Krebozo Le 30R50, Kurebozoru 50R50, DuPont Ludox (TM) HS-40, Ludox HS-30, Ludox LS, include Ludox SM-30 and the like.

  Although it does not specifically limit as colloidal silica which uses a water-soluble solvent as a dispersion medium, For example, Nissan Chemical Industries Co., Ltd. MA-ST-M (Methanol dispersion type whose number average particle diameter is 20 nm-25 nm) is a commercial item. IPA-ST (isopropyl alcohol dispersion type with a number average particle diameter of 10 nm to 15 nm), EG-ST (ethylene glycol dispersion type with a number average particle diameter of 10 nm to 15 nm), EG-ST-ZL (number average particle diameter is 70 nm to 100 nm ethylene glycol dispersion type), NPC-ST (number average particle diameter of 10 nm to 15 nm ethylene glycol monopropyl ether dispersion type) and the like.

  These colloidal silicas may be used alone or in combination of two or more. Colloidal silica (A) may contain alumina, sodium aluminate or the like as a minor component. Colloidal silica may contain an inorganic base (such as sodium hydroxide, potassium hydroxide, lithium hydroxide, or ammonia) or an organic base (such as tetramethylammonium) as a stabilizer.

[Polymer particles (B)]
The polymer particles (B) have a core containing the infrared absorbing material (b1) and a shell covering the core and containing the polymer (b2).

(Infrared absorbing material (b1))
By including the infrared absorbing material (b1) as the core of the polymer particles (B), aggregation of the infrared absorbing materials (b1) can be suppressed, and the mixing stability of the infrared absorbing material in the heat shielding composition. Will be improved.

  The infrared absorbent (b1) is not particularly limited as long as it is an absorbent having an absorption band in the infrared region (wavelength of 800 nm or more), and examples thereof include organic fine particles, inorganic fine particles, and mixtures thereof.

  The organic fine particles are not particularly limited, and specific examples include cyanine-based, porphyrin-based, phthalocyanine-based and the like.

The inorganic fine particles are not particularly limited, and specifically, at least one selected from the group consisting of indium oxide doped with tin, tin oxide doped with antimony, cerium oxide, zinc oxide, antimony oxide, and a composite thereof. Transparent conductive fine particles of seeds; noble metal fine particles such as silver, gold, platinum, rhodium, palladium; formula M _x W _y O _z (where M element is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, One or more elements selected from the group consisting of Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, and I Represents W Tungsten, O represents oxygen, and composite tungsten oxide represented by 0.0001 ≦ x / y ≦ 1.5, 1.0 ≦ z / y ≦ 5.0); zirconium oxide, tin oxide, oxidation Examples thereof include fine particles having absorption in the ultraviolet region such as bismuth and titanium oxide. An inorganic fine particle may be used individually by 1 type, or may use 2 or more types together.

  Among these, the infrared absorbing material (b1) is at least one selected from the group consisting of indium oxide doped with tin, tin oxide doped with antimony, cerium oxide, zinc oxide, antimony oxide, and a complex thereof. It is preferable to include. By using such an infrared absorbing material (b1), the infrared absorption efficiency tends to be superior.

  The infrared absorbent (b1) preferably has no absorption in the infrared wavelength of sunlight, particularly in the wavelength region corresponding to the absorption band of silicon. The average reflectance of the infrared absorbing agent (b1) in the visible ultraviolet light region wavelength of 300 nm to 780 nm is preferably 25% or less, more preferably 20% or less, and further preferably 15% or less. The lower limit of the average reflectance in the visible ultraviolet region wavelength of 300 nm to 780 nm is preferably as low as possible, and more preferably 2% or less. When the average reflectance in the visible ultraviolet region wavelength of 300 nm to 780 nm is within the above range, the transmitted light used for the power generation of the solar cell tends to be excellent by not being reduced. In addition, the average reflectance in visible ultraviolet light region wavelength 300nm -780nm can be measured with a reflection spectrometer.

  Moreover, 15% or more is preferable, as for the average reflectance in the infrared region wavelength of 780 nm-2500 nm of an infrared absorber (b1), 20% or more is more preferable, and 25% or more is further more preferable. The upper limit of the average reflectance in the infrared region wavelength of 780 nm to 2500 nm is preferably 80% or less. When the average reflectance in the infrared region wavelength of 780 nm to 2500 nm is within the above range, it tends to be excellent by providing a heat shielding function without reducing transmitted light used for power generation of the solar cell. In addition, the average reflectance in infrared region wavelength 780 nm-2500 nm can be measured with a reflection spectrometer.

  0.1% or more is preferable, as for the absorption in infrared region wavelength 1000nm-2500nm of an infrared absorber (b1), 10% or more is more preferable, and 20% or more is further more preferable. The upper limit of absorption in the infrared region wavelength of 1000 nm to 2500 nm is preferably 80% or less. The region with a wavelength of 1000 nm to 2500 nm is a wavelength region where infrared rays are efficiently converted into heat, and absorption in the wavelength region of a wavelength of 1000 nm to 2500 nm is within the above range, so that transmitted light used for power generation of solar cells can be reduced. It tends to be excellent by providing a heat shielding function without reducing it. In addition, since this wavelength region overlaps with the absorption region of silicon, the addition amount can be adjusted according to the infrared absorption ability of the infrared absorber. Absorption in the infrared region wavelength of 1000 nm to 2500 nm can be measured by an ultraviolet-visible absorption spectrum.

  The number average particle diameter of the infrared absorbing agent (b1) is preferably 5 nm to 200 nm, more preferably 5 nm to 150 nm, and still more preferably 5 nm to 100 nm. When the number average particle diameter is 5 nm or more, the blending stability tends to be more excellent. Moreover, since the number average particle diameter is 200 nm or less, it is possible to further suppress the scattering of light having the absorption band wavelength of silicon due to the scattering caused by the particles of the infrared absorbing agent (b1). There is a tendency that the rise in temperature can be efficiently suppressed without adversely affecting it. Moreover, when the number average particle diameter is 200 nm or less, even when the amount of component (A) added is large, the scattered light does not become strong and the power generation efficiency of the solar cell tends not to decrease.

(Polymer (b2))
Although it does not specifically limit as a polymer (b2) which comprises the shell of a polymer particle (B), For example, a polyurethane-type polymer, a polyester-type polymer, a poly (meth) acrylate type polymer, a polyvinyl acetate type polymer , Polybutadiene polymer, polyvinyl chloride polymer, chlorinated polypropylene polymer, polyethylene polymer, polystyrene polymer, polystyrene- (meth) acrylate copolymer, rosin derivative, styrene-maleic anhydride Examples thereof include a polymer composed of an alcohol adduct of a copolymer and a polycarbonyl compound such as a cellulose resin.

  The polymer (b2) preferably contains a polymer of a hydrolyzable silicon compound (b3) and a vinyl monomer (b4) having a secondary and / or tertiary amide group. Although it does not specifically limit as a hydrolysable silicon compound (b3) and a vinyl monomer (b4), For example, the thing similar to what is mentioned later can be used. By using such a polymer (b2), the coating film tends to be more excellent in hydrophilicity (antifouling property).

  The polymer particles (B) used in the present embodiment are not particularly limited, but in the presence of water and an emulsifier, the infrared absorbing material (b1), the hydrolyzable silicon compound (b3), the secondary and / or Polymer particles obtained by polymerizing a vinyl monomer (b4) having a tertiary amide group are preferred. The form of such polymer particles (B) is not particularly limited, but for example, polymer emulsion particles are preferable. By using such polymer particles (B), the transparency of the coating film tends to be superior. In addition, it does not specifically limit as an emulsifier, For example, the thing similar to what is mentioned later can be used.

(Hydrolyzable silicon compound (b3))
Although it does not specifically limit as a hydrolysable silicon compound (b3) used for manufacturing a polymer particle (B), For example, what is illustrated by the hydrolyzable silicon compound (C) mentioned later is mentioned.

  In addition, these hydrolyzable silicon compounds (b3) may be used individually by 1 type, or may use 2 or more types together.

(Vinyl monomer (b4))
The vinyl monomer (b4) having a secondary and / or tertiary amide group used for producing the polymer particles (B) is not particularly limited, and for example, N-alkyl or N-alkylene substitution (meta ) Acrylamide and the like can be exemplified. Specifically, for example, N-methylacrylamide, N-methylmethacrylamide, N-ethylacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-diethylacrylamide, N-ethylmethacrylamide, N-methyl-N-ethylacrylamide, N-methyl-N-ethylmethacrylamide, N-isopropylacrylamide, Nn-propylacrylamide, N-isopropylmethacrylamide, Nn-propylmethacrylamide, N-methyl-N -N-propylacrylamide, N-methyl-N-isopropylacrylamide, N-acryloylpyrrolidine, N-methacryloylpyrrolidine, N-acryloylpiperidine, N-methacryloylpiperidine, N-acryloyl Oxahydroazepine, N-acryloylmorpholine, N-methacryloylmorpholine, N-vinylpyrrolidone, N-vinylcaprolactam, N, N′-methylenebisacrylamide, N, N′-methylenebismethacrylamide, N-vinylacetamide, diacetone Examples include acrylamide, diacetone methacrylamide, N-methylol acrylamide, N-methylol methacrylamide and the like.

  The amide group of the vinyl monomer (b4) used for producing the polymer particles (B) may be either secondary or tertiary, but a tertiary amide group is preferred. By using the vinyl monomer (b4) having a tertiary amide group, the interaction property such as hydrogen bonding between the obtained polymer particles (B) and the colloidal silica (A) tends to become stronger. . Among such vinyl monomers (b4), N, N-diethylacrylamide is very excellent in polymerization stability in the presence of water and an emulsifier, and is formed by polymerization of the hydrolyzable silicon compound (b3) described above. Since it is possible to form a strong hydrogen bond with the hydroxyl group of the product or the hydroxyl group of colloidal silica (A), it is more preferable.

[Production method of polymer particles (B)]
The method for obtaining the polymer particles (B) having the infrared absorbing material (b1) as a core is not particularly limited. For example, a seed polymerization method in which emulsion particles are previously present in an aqueous phase and polymerized is preferable. The seed polymerization method is not particularly limited. For example, the hydrolyzable silicon compound (b3) and the vinyl monomer (b4) are directly or emulsified in a reaction vessel in which emulsion particles of the infrared absorbing material (b1) are dispersed. In such a state, there may be mentioned a method of polymerizing in the presence of a polymerization catalyst by dropping all at once, dividing or continuously. The reaction pressure is preferably from atmospheric pressure to 10 MPa. The reaction temperature is preferably 30 to 150 ° C. In addition, you may change a pressure and reaction temperature as needed.

  An emulsifier may be used for the synthesis of the polymer particles (B). Although it does not specifically limit as an emulsifier, For example, acidic emulsifiers, such as alkylbenzenesulfonic acid, alkylsulfonic acid, alkyl sulfosuccinic acid, polyoxyethylene alkyl sulfuric acid, polyoxyethylene alkyl aryl sulfuric acid, polyoxyethylene distyryl phenyl ether sulfonic acid; Anionic surfactants such as alkali metal (Li, Na, K, etc.) salts of acidic emulsifiers, ammonium salts of acidic emulsifiers, fatty acid soaps; quaternary ammoniums such as alkyltrimethylammonium bromide, alkylpyridinium bromide, imidazolinium laurate Salt, pyridinium salt, imidazolinium salt type cationic surfactants; polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan fatty acid ester, polyoxyethyleneoxypro Ren block copolymer, nonionic surface active agent polyoxyethylene distyryl phenyl ether; reactive emulsifier or the like having a radical polymerizable double bond.

  Among these emulsifiers, a reactive emulsifier having a radical polymerizable double bond is preferable. By using a reactive emulsifier, the water dispersion stability of the resulting polymer particles (B) is further improved, and a thermal barrier coating film with excellent water resistance, chemical resistance, optical properties, strength, etc. is formed. Tend to be able to.

  Although it does not specifically limit as a reactive emulsifier, For example, the vinyl monomer which has a sulfonic acid group or a sulfonate group, the vinyl monomer which has a sulfate ester group, those alkali metal salts, or ammonium salt; Polyoxyethylene etc. Examples thereof include vinyl monomers having a nonionic group; vinyl monomers having a quaternary ammonium salt.

  The salt of the vinyl monomer having a sulfonic acid group or a sulfonate group is not particularly limited, and examples thereof include an ammonium salt, a sodium salt, or a potassium salt having a radical polymerizable double bond and a sulfonic acid group. Alkyl group having 1 to 20 carbon atoms, alkyl ether group having 2 to 4 carbon atoms, polyalkyl ether group having 2 to 4 carbon atoms, aryl group having 6 or 10 carbon atoms, and succinic acid partially substituted with a group A compound having a substituent selected from the group consisting of a group; a vinyl sulfonate compound having a vinyl group to which a group which is an ammonium salt, sodium salt or potassium salt of a sulfonic acid group is bonded.

  As a compound having an alkyl ether group having 2 to 4 carbon atoms or a polyalkyl ether group having 2 to 4 carbon atoms, partially substituted by a group which is an ammonium salt, sodium salt or potassium salt of a sulfonic acid group, Although not limited, for example, Aqualon HS-10 or KH-1025 (trade name) (Daiichi Kogyo Seiyaku Co., Ltd.), Adekaria soap SE-1025N or SR-1025 (trade name) (Asahi Denka Kogyo Co., Ltd.) Manufactured).

  Although it does not specifically limit as a compound which has a succinic acid group partially substituted by the group which is ammonium salt of a sulfonic acid group, sodium salt, or potassium salt, For example, allyl sulfo succinate etc. are mentioned. These can also use a commercial item, and it is not specifically limited as a commercial item, For example, Eleminol JS-2 (brand name) (made by Sanyo Chemical Co., Ltd.), Latemuru S-120, S-180A or S- 180 (trade name) (manufactured by Kao Corporation).

  The vinyl monomer having a nonionic group is not particularly limited. For example, α- [1-[(allyloxy) methyl] -2- (nonylphenoxy) ethyl] -ω-hydroxypolyoxyethylene (trade name: ADEKA) Rear soap NE-20, NE-30, NE-40, etc., manufactured by Asahi Denka Kogyo Co., Ltd., polyoxyethylene alkylpropenyl phenyl ether (trade names: Aqualon RN-10, RN-20, RN-30, RN- 50, etc., manufactured by Daiichi Pharmaceutical Co., Ltd.).

  In the polymer particles (B) used in the present embodiment, components that are usually added to and blended with paints and molding resins, for example, thickeners, leveling agents, thixotropic agents, etc., depending on the application and method of use. Agent, antifoaming agent, freezing stabilizer, matting agent, cross-linking reaction catalyst, pigment, curing catalyst, cross-linking agent, filler, anti-skinning agent, dispersant, wetting agent, light stabilizer, antioxidant, UV absorption Agent, rheology control agent, antifoaming agent, film forming aid, rust preventive agent, dye, plasticizer, lubricant, reducing agent, antiseptic, antifungal agent, deodorant, anti-yellowing agent, antistatic agent Or a charge control agent etc. can be mix | blended.

[Hydrolyzable silicon compound (C)]
The heat-insulating composition according to this embodiment can further contain a hydrolyzable silicon compound (C). By including the hydrolyzable silicon compound (C), a bond is formed by a condensation reaction between the silanol group of the hydrolyzable silicon compound (C) and the hydroxyl group present on the surface of the colloidal silica (A), or The mechanical strength of the coating film tends to increase due to the formation of hydrogen bonds between the hydrolyzable silicon compound (C) and the colloidal silica (A).

  Although it does not specifically limit as a hydrolysable silicon compound (C), For example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, Tetraalkoxysilanes such as tetra-sec-butoxysilane and tetra-tert-butoxysilane; trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, isobutyltrie Xysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, cyclohexyltrimethoxysilane, Cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3- Trifluoropropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltrimethoxysilane, 2-hydroxyethyltriethoxy Silane, 2-hydroxypropyltrimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acrylic Loxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethylate Limethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloyloxy Trialkoxysilanes such as propyltri-n-propoxysilane, 3- (meth) acryloyloxypropyltriisopropoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane; dimethoxysilane, diethoxysilane , Methyldimethoxysilane, methyldiethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyl Ethoxysilane, diisopropyldimethoxysilane, diisopropyldiethoxysilane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-pentyldimethoxysilane, di-n-pentyldiethoxysilane, di-n- Hexyldimethoxysilane, di-n-hexyldiethoxysilane, di-n-heptyldimethoxysilane, di-n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di-n-octyldiethoxysilane, di-n Dialkoxysilanes such as cyclohexyldimethoxysilane, di-n-cyclohexyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane; trimethylmethoxysilane Monoalkoxysilanes such as trimethylethoxysilane; tetraacetoxysilane, tetrakis (trichloroacetoxy) silane, tetrakis (trifluoroacetoxy) silane, triacetoxysilane, tris (trichloroacetoxy) silane, tris (trifluoroacetoxy) silane, methyl Acetoxysilanes such as triacetoxysilane, methyltris (trichloroacetoxy) silane; tetrachlorosilane, tetrabromosilane, tetrafluorosilane, trichlorosilane, tribromosilane, trifluorosilane, methyltrichlorosilane, methyltribromosilane, methyltri Halogenated silanes such as fluorosilane; tetrakis (methylethylketoxime) silane, tris (methylethylketoxime) silane, methylto Ketoxinium silanes such as ris (methyl ethyl ketoxime) silane, phenyl tris (methyl ethyl ketoxime) cin, bis (methyl ethyl ketoxime) silane, methyl bis (methyl ethyl ketoxime) silane; silazanes such as hexamethyldisilazane, hexamethylcyclotrisilazane; Bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, bis (triphenoxysilyl) methane, bis (trimethoxysilyl) ethane, bis (triethoxysilyl) ethane, bis (triphenoxysilyl) ethane, 1, 3-bis (trimethoxysilyl) propane, 1,3-bis (triethoxysilyl) propane, 1,3-bis (triphenoxysilyl) propane, 1,4-bis (trimethoxysilyl) benzene, 1,4- Bis (trier Kishishiriru) benzene, bis (dimethylamino) dimethylsilane, bis (diethylamino) dimethylsilane, bis (dimethylamino) methylsilane, bis (diethylamino) other silanes such as methylsilane and the like.

[Thermal barrier coating]
The thermal barrier coating film according to this embodiment includes a polymer particle (B) including a core including an infrared absorbing material (b1), a shell covering the core and including a polymer (b2), It has the colloidal silica (A) couple | bonded with the silanol group and / or amide group of the coalesced particle (B) surface by a covalent bond and / or a hydrogen bond. The thermal barrier coating film according to the present embodiment can be obtained, for example, by applying and drying the thermal barrier composition according to the present embodiment. Since the obtained heat-shielding coating film has surface hydrophilicity resulting from colloidal silica (A) or a hydrolyzable silicon compound added as necessary, it is considered to have an antifouling effect. That is, since the thermal barrier coating film has surface hydrophilicity, adhesion of dirt such as dust is reduced by its antistatic effect, and even if dirt is adhered, it is considered that it is washed away by rainwater. However, the mechanism does not depend on this. Moreover, since this thermal barrier coating film is excellent in total light transmittance and has an infrared thermal barrier effect, it can be suitably used as a protective film for solar cells. In addition, the covalent bond and / or hydrogen bond between the silanol group and / or amide group on the surface of the polymer particle (B) and the colloidal silica (A) should be confirmed by measuring the thermal barrier coating film by FTIR. Can do.

[Heat shield]
The heat shielding member according to the present embodiment includes a base material and a thermal barrier coating film formed by applying the heat shielding composition on the base material and drying the base material. Moreover, since the heat shielding member has antifouling properties, is excellent in total light transmittance, and has an infrared heat shielding effect, it can be suitably used as a protective member for solar cells.

  The substrate used in the present embodiment is not particularly limited, and for example, a material whose material is glass or resin is preferably used. Further, from the viewpoint of transparency, weather resistance, and weight reduction, the material constituting the substrate is selected from the group consisting of glass, acrylic resin, polycarbonate resin, cyclic olefin resin, polyethylene terephthalate resin, and ethylene-fluoroethylene copolymer. Preferably, at least one kind of material or a composite material thereof is used. A weathering agent or the like may be further kneaded into the acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate resin, or ethylene-fluoroethylene copolymer for the purpose of imparting weather resistance.

  Moreover, the solar cell heat shield member according to the present embodiment is based on, for example, the above heat shield composition dispersed in a solvent such as water (hereinafter sometimes simply referred to as “water dispersion”). It is formed by applying on the material and drying. Here, the solid content concentration of the aqueous dispersion is preferably 0.01 to 60% by mass, and more preferably 1 to 40% by mass. The viscosity of the aqueous dispersion is preferably 0.1 to 100,000 mPa · s, more preferably 1 to 10,000 mPa · s at 20 ° C. Furthermore, as a method for applying the heat shielding composition to the substrate, for example, spray spraying method, flow heat shielding method, roll coating method, bar coating method, brush coating method, dip heat shielding method, spin heat shielding method, screen printing Method, casting method, gravure printing method, flexographic printing method and the like. In addition, after drying a coating film on a base material, it is also possible to obtain by performing heat processing, ultraviolet irradiation, etc. preferably at 100 degrees C or less if desired.

  EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to a following example, unless the summary is exceeded. Various physical properties were evaluated by the following methods.

1. Number average particle size The sample is colloidal contained in the sample by using a wet particle size analyzer (Nikkiso Microtrac UPA-9230) and diluting by adding an appropriate solvent so that the solid content in the sample is 1 to 20% by mass. The number average particle diameter of silica or polymer particles was measured.

2. Antifouling (initial contact angle)
After placing a drop of deionized water on the surface of the thermal barrier coating and leaving it at 23 ° C. for 1 minute, contact the water drop using a contact angle measurement device (Kyowa Interface Science, CA-X150 contact angle meter). The corner was measured.

3. Total light transmittance Using a turbidimeter (trade name “NDH2000” manufactured by Nippon Denshoku Industries Co., Ltd.), the total light transmittance of the laminate (heat shielding member) of white plate glass and thermal barrier coating film according to JIS-K7105. The rate was measured.

4). Formulation stability The heat-shielding composition was filtered with 400 mesh, and the presence or absence of a residue was confirmed. Those in which almost no residue was confirmed were considered good. Moreover, the thing in which the residue was confirmed was evaluated that there was an aggregated precipitate.

5. Infrared shielding effect (infrared absorptance)
An infrared spectrophotometer ("FT / IR4100" manufactured by JASCO Corporation was used to measure the infrared absorptivity of the thermal barrier coating (measurement wavelength: 1300 nm)

6). Solar cell module temperature A solar cell module obtained by applying a heat-shielding composition to a solar cell with a rated output of 70 W is exposed outdoors (Fuji City, Shizuoka, Japan) at an inclination angle of 30 degrees, and on the back of the module. The temperature of the solar cell module was measured with the attached thermocouple. The weather at the time of measurement was fine and the atmospheric temperature was 25 ° C.

[Production Example 1]
-Synthesis of polymer particle (B-1) aqueous dispersion In a reactor having a reflux condenser, a dropping tank, a thermometer and a stirrer, 1400 g of ion-exchanged water, ZnO ₂ · Sb ₂ O ₅ composite particles (solid content 30 0.5%) 200 g and 7 g of dodecylbenzenesulfonic acid were added, and the mixture was heated to 80 ° C. with stirring to obtain a mixed solution (1). To the obtained mixed liquid (1), 300 g of 3-methacryloxypropyltrimethoxysilane was dropped over about 2 hours while maintaining the temperature in the reaction vessel at 80 ° C. to obtain a mixed liquid (2). Thereafter, the mixed liquid (2) was stirred for about 1 hour in a state where the temperature in the reaction vessel was 80 ° C. to obtain a mixed liquid (3). Next, a mixed liquid (4) containing 150 g of butyl acrylate, 30 g of tetraethoxysilane, 145 g of phenyltrimethoxysilane, and 1.3 g of 3-methacryloxypropyltrimethoxysilane in the obtained mixed liquid (3), 165 g of diethyl acrylamide, 3 g of acrylic acid, 13 g of reactive emulsifier (trade name “ADEKA rear soap SR-1025”, manufactured by Asahi Denka Co., Ltd., solid content 25% by mass aqueous solution), 40 g of 2% by mass aqueous solution of ammonium persulfate, and ions A mixture (5) containing 1900 g of exchange water was simultaneously added dropwise over about 2 hours while maintaining the temperature in the reaction vessel at 80 ° C. to obtain a mixture (6). Further, as a heat curing, the mixture (6) was stirred for about 2 hours while the temperature in the reaction vessel was 80 ° C. Thereafter, the mixture (6) was cooled to room temperature, filtered through a 100-mesh wire mesh, filtered through a 100-mesh wire mesh, the solid content in the liquid was adjusted to 10.0% by mass with ion-exchanged water, and the number average An aqueous dispersion of polymer particles (B-1) having a particle diameter of 100 nm was obtained.

[Production Example 2]
Into a reaction vessel having a reflux condenser, a dropping tank, a thermometer and a stirring device, 1600 g of ion-exchanged water and 6 g of dodecylbenzenesulfonic acid were added, and then the temperature was heated to 80 ° C. with stirring. To this, a mixed solution of 185 g of dimethyldimethoxysilane and 117 g of phenyltrimethoxysilane was dropped over about 2 hours while keeping the temperature in the reaction vessel at 80 ° C., and then the temperature in the reaction vessel was raised to 80 ° C. Stirring was continued for about 1 hour in the maintained state. Next, a mixed solution containing 86 g of butyl acrylate, 133 g of phenyltrimethoxysilane and 1.3 g of 3-methacryloxypropyltrimethoxysilane, 137 g of diethylacrylamide, 3 g of acrylic acid, a reactive emulsifier (manufactured by Asahi Denka Co., Ltd., product Name "Adekaria soap SR-1025", solid content 25 mass% aqueous solution) 13 g, ammonium persulfate 2 mass% aqueous solution 40 g and ion-exchanged water 1900 g mixed liquid was maintained at a temperature of 80 ° C in the reaction vessel. In the state, it was dripped simultaneously over about 2 hours. Further, stirring was continued for about 2 hours while maintaining the temperature in the reaction vessel at 80 ° C., and then the liquid was cooled to room temperature and filtered through a 100-mesh wire mesh, and then the solid content in the liquid was removed with ion-exchanged water. The aqueous dispersion of polymer particles (B-2) having a number average particle diameter of 70 nm as component (B) was obtained by adjusting to 10.0% by mass.

[Example 1]
Colloidal silica (manufactured by Nissan Chemical Industries, Ltd., trade name “Snowtex-OS” ((A
) Component) was diluted with water to prepare a dispersion having a solid content of 10% by mass (number average particle diameter of particles 8 nm). The dispersion and the aqueous dispersion of polymer particles (B-1) synthesized in Production Example 1 are blended at a ratio of A / B = 100/100 (mass ratio) in terms of solid content, and the heat shielding composition. Got. The obtained heat-shielding composition was applied on white plate glass (thickness 2 mm, 6 × 6 cm square) by dip coating so as to have a film thickness of 1000 nm, and then dried at 70 ° C. for 30 minutes to obtain a heat-shielding coating film. It was. The blending stability of the obtained heat shielding composition was good. Table 1 shows the physical properties of the obtained thermal barrier coating.

[Example 2]
Example 2 In the same manner as in Example 1, except that tetraethoxysilane (special grade reagent manufactured by Wako Pure Chemical Industries) was added as a component at a ratio of A / B / C = 100/100/40 (mass ratio). A thermal barrier composition and a thermal barrier coating film were obtained. The blending stability of the obtained heat shielding composition was good. Table 1 shows the physical properties of the obtained thermal barrier coating.

[Comparative Example 1]
A thermal barrier composition and a thermal barrier coating film of Comparative Example 1 were obtained in the same manner as Example 2 except that the component B was not included. The blending stability of the obtained heat shielding composition was good. Table 1 shows the physical properties of the obtained thermal barrier coating.

[Comparative Example 2]
Instead of the polymer particles (B-1), ZnO ₂ · Sb ₂ O ₅ composite particles (solid content 30.5%) are used as the b1 component at a ratio of A / b1 / C = 100/10/40 (mass ratio). A heat shielding composition and a heat shielding coating film of Comparative Example 2 were obtained in the same manner as Example 2 except for the addition. Aggregated precipitates were confirmed in the obtained heat shielding composition, and the blending stability was low. Table 1 shows the physical properties of the obtained thermal barrier coating.

[Comparative Example 3]
Colloidal silica (manufactured by Nissan Chemical Industries, Ltd., trade name “Snowtex-OS” (component (A)) is diluted with water to form a dispersion having a solid content of 10% by mass (number average particle diameter of particles 8 nm). The ZnO ₂ · Sb ₂ O ₅ composite particles (solid content 30.5%) (component (b1)) and the aqueous dispersion of the polymer particles (B-2) synthesized in Production Example 2 were prepared. It mix | blended in the ratio of A / b1 / B-2 = 100/5/100 (mass ratio) in conversion of solid content, and obtained the heat-shielding composition and the heat-shielding coating film of the comparative example 3. The obtained heat-shielding composition. Aggregated precipitates were confirmed in the product, and the blending stability was low, and the physical properties of the obtained thermal barrier coating are shown in Table 1.

  From the above, it was confirmed that the heat-shielding composition of each example is excellent in blending stability, antifouling property, and total light transmittance, and can contribute to the improvement of power generation efficiency by suppressing the temperature rise of the solar cell by the infrared shielding effect. It was.

Since the coating film using the heat-shielding composition of the present invention is excellent in antifouling property, total light transmittance, and infrared shielding property, and can suppress the temperature rise of the solar cell, particularly in the field of crystal type solar cells. Has industrial applicability.

Claims (7)

Including colloidal silica (A) and polymer particles (B),
The polymer particles (B), a core comprising an infrared absorbing material (b1), and covering the core, have a, a shell comprising a polymer (b2),
The polymer particles (B) have a silanol group and / or an amide group on the surface,
The colloidal silica (A) has a number average particle diameter of 1 nm to 400 nm,
The infrared absorbing material (b1) contains a composite of zinc oxide and antimony oxide, and the number average particle diameter is 5 nm to 200 nm.
Thermal barrier composition. Further comprising hydrolyzable silicon compound (C), thermal barrier composition of claim 1. The polymer (b2), hydrolyzable silicon compound (b3), including vinyl monomers having secondary and / or tertiary amide group and (b4), a polymer, to claim 1 or 2 The heat shielding composition as described. In the presence of water and an emulsifier, the polymer particles (B) have the infrared absorber (b1), the hydrolyzable silicon compound (b3), and the vinyl unit having a secondary and / or tertiary amide group. The heat-shielding composition according to any one of claims 1 to 3 , comprising polymer particles obtained by polymerizing the monomer (b4). A heat-shielding member comprising: a base material; and a thermal barrier coating film formed by applying the heat-shielding composition according to any one of claims 1 to 4 and drying the substrate. The heat shielding member according to claim 5 , which is a solar cell protective member. Polymer particles (B) comprising a core containing an infrared absorbing material (b1), and a shell covering the core and containing a polymer (b2);
Possess the polymer particles (B) silanol groups on the surface and / or amide groups and covalent and / or hydrogen bonds with bound colloidal silica (A), a,
The colloidal silica (A) has a number average particle diameter of 1 nm to 400 nm,
The infrared absorbing material (b1) contains a composite of zinc oxide and antimony oxide, and the number average particle diameter is 5 nm to 200 nm.
Thermal barrier coating.