UV / Near-infrared shielding coating composition and its uses

Abstract

To provide an ultraviolet ray / near-infrared ray shielding coating composition which is a silicone-based coating composition, has no need of dispersion by a specific surfactant, and thereby has high versatility while having both of ultraviolet shielding performance and near-infrared ray shielding performance, and by which good coating solution and coating film transparency can be obtained; and to provide a method for manufacturing an ultraviolet ray / near-infrared ray shielding coating layer.SOLUTION: An ultraviolet ray / near-infrared ray shielding coating composition includes components (a) to (d) shown below: (a) an amino group-containing silane compound represented by the following formula (I) R4-n-Si-(OR')n -(I) (wherein, R is an amino group-containing organic group; R' is a methyl group, an ethyl group or a propyl group; and n is an integer selected from among 1-3) (b) at least one boron compound selected from the group consisting of H3BO3 and B2O3; (c) an organic ultraviolet ray-absorbing agent; (d) a conductive metal oxide. The amount of (b) a boron compound to 1 mol of (a) an amino-group containing silane compound is 0.02 to 1.0 mol.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an ultraviolet / near infrared shielding coating composition and uses thereof, and more specifically to an ultraviolet / near infrared shielding coating composition which effectively shields ultraviolet and near infrared rays, is highly versatile since it does not require dispersion with a specific surfactant, and can provide a good coating solution and coating film transparency. [Background technology]

[0002] Silicone-based compositions such as alkoxysilanes, their polymers, and their hydrolysates can be cured at room temperature, and are therefore used as coating agents for glass, ceramics, plastics, and the like. In order to impart an ultraviolet shielding function to the coating, an organic ultraviolet absorber can be added to the coating agent. However, in this case, the haze tends to increase (the transparency of the coating film tends to decrease), and it has been proposed to adjust the type and amount of organic ultraviolet absorber added in order to reduce the haze (see, for example, Patent Document 1). On the other hand, conductive metal oxides such as ATO and ITO are known as solar radiation shielding materials that can remove or reduce near-infrared rays, which contribute greatly to the thermal effect in sunlight, while transmitting visible light. Transparent near-infrared shielding coating compositions using ATO and ITO have been used on glass, ceramics, and transparent plastics (see, for example, Patent Documents 2 and 3). As a coating composition capable of blocking both ultraviolet and near infrared rays, an ultraviolet / near infrared shielding coating composition is known (see, for example, Patent Document 4). However, zinc oxide used as an ultraviolet shielding material in this technology is prone to undesirable phenomena such as a decrease in solution stability due to secondary aggregation, and since it is necessary to select and disperse a specific surfactant, the freedom of formulation design is limited and versatility is poor. Furthermore, it was thought that the photocatalytic action may cause problems in the coating film. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-80106 A [Patent Document 2] JP 2008-111048 A [Patent Document 3] International Publication No. 2008 / 029620 A1 Brochure [Patent Document 4] Patent Publication No. 2021-176943 Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the limitations of the prior art described above, the present invention aims to provide an ultraviolet / near-infrared shielding coating composition and a method for producing an ultraviolet / near-infrared shielding coating layer, which is a silicone-based coating composition that has both ultraviolet shielding ability and near-infrared shielding ability, is highly versatile because it does not require dispersion with a specific surfactant, and is capable of providing a good coating solution and coating film transparency. [Means for solving the problem]

[0005] As a result of intensive research, the present inventors have found that in an ultraviolet and near infrared shielding coating composition which combines an organic ultraviolet absorber and a conductive metal oxide with a basic structure formed from a silane compound having an amino group having a specific structure and a boron compound having a specific structure, by setting the ratio of the silane compound to the boron compound within a specific molar ratio range, it is possible to achieve high versatility without the need for a specific surfactant, and to achieve a coating solution with good stability and a coating film with excellent transparency, thereby solving the above-mentioned problems, and have completed the present invention. That is, the present invention provides: [1] An ultraviolet and near infrared shielding coating composition comprising the following components (a) to (d): (a) a silane compound containing an amino group represented by the following formula (I): R4-n -Si-(OR') n -(I) (In the formula, R represents an amino group-containing organic group, R' represents a methyl group, an ethyl group, or a propyl group, and n represents an integer selected from 1 to 3.); (b)H 3 BO 3 and B. 2 O 3 at least one boron compound selected from the group consisting of: (c) organic ultraviolet absorbers; (d) conductive metal oxide; wherein the amount of (b) the boron compound relative to 1 mole of (a) the silane compound containing an amino group is 0.02 to 1.0 mole.

[0006] Moreover, the following [2] to

[13] are each a preferred aspect or embodiment of the present invention. [2] (b) The ultraviolet-near infrared shielding coating composition according to [1], wherein the amount of the boron compound is 0.1 to 0.75 mol. [3] (b) The ultraviolet-near infrared shielding coating composition according to [1], wherein the amount of the boron compound is 0.2 to 0.59 mol. [4] (c) The ultraviolet and near infrared shielding coating composition according to any one of [1] to [3], wherein the organic ultraviolet absorber is selected from the group consisting of benzotriazole-based compounds, triazine-based compounds, and benzophenone-based compounds. [5] (c) The ultraviolet and near infrared shielding coating composition according to [4], wherein the organic ultraviolet absorber is a benzotriazole-based compound or a triazine-based compound. [6] The ultraviolet and near infrared shielding coating composition according to any one of [1] to [5], further comprising a light stabilizer. [7] The ultraviolet and near infrared shielding coating composition according to any one of [1] to [6], further comprising (e) an organic functional group-containing silane compound (excluding those corresponding to the above component (a)). [8] (e) The ultraviolet and near infrared shielding coating composition according to [7], wherein the organic functional group-containing silane compound includes an alkoxy group-containing silane compound. [9] (d) The ultraviolet-near infrared shielding coating composition according to any one of [1] to [8], wherein the conductive metal oxide is at least one oxide selected from the group consisting of ITO (indium tin oxide) and ATO (antimony tin oxide).

[10] (c) The ultraviolet- and near-infrared shielding coating composition according to any one of [1] to [9], wherein the amount of the organic ultraviolet absorber added is 0.5 to 5.0 parts by mass, based on 100 parts by mass of the entire ultraviolet- and near-infrared shielding coating composition.

[11] The ultraviolet and near infrared shielding coating composition according to any one of [1] to

[10] , which is substantially free of any of a phosphate-based surfactant and an acrylic-based surfactant.

[12] A method for producing an ultraviolet-near infrared shielding coating layer, comprising the step of applying the ultraviolet-near infrared shielding coating composition according to any one of [1] to

[11] .

[13] The method for producing an ultraviolet-near infrared shielding coating layer according to

[12] , which forms a coating layer having a light transmittance of 20% or less at wavelengths of 280 to 380 nm and a light transmittance of 40% or less at wavelengths of 780 to 2500 nm.

[14] The method for producing an ultraviolet-near infrared shielding coating layer according to

[12] or

[13] , comprising forming a coating layer on a transparent substrate. Effect of the Invention

[0007] According to the present invention, there are provided a coating composition having high versatility and good solution stability, which can realize a coating film having an ultraviolet shielding function and a near-infrared shielding function and having excellent transparency, and a method for producing a coating layer. The ultraviolet and near infrared shielding coating composition of the present invention combines the above-mentioned preferable properties at a high level that surpasses the limitations of conventional technology, and therefore has a high degree of freedom in preparation, storage, coating, etc., and can be applied to glass surfaces, film surfaces, transparent plastic surfaces, etc. of buildings and car windows to form a coating layer, which can reduce or prevent the penetration of ultraviolet and infrared rays from sunlight while maintaining high visibility, prevent sunburn on the human body and deterioration and damage to products and exhibits caused by ultraviolet rays, and suppress the rise in temperature inside rooms, cars, etc., thereby achieving technical effects of great practical value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention relates to an ultraviolet-near infrared shielding coating composition comprising the following components (a) to (d): (a) a silane compound containing an amino group represented by the following formula (I): R 4-n -Si-(OR') n -(I) (In the formula, R represents an amino group-containing organic group, R' represents a methyl group, an ethyl group, or a propyl group, and n represents an integer selected from 1 to 3.); (b)H 3 BO 3 and B. 2 O 3 at least one boron compound selected from the group consisting of: (c) organic ultraviolet absorbers; (d) Conductive metal oxide. In the present invention, the amount of (b) the boron compound per mole of (a) the silane compound containing an amino group is within the range of 0.02 to 1.0 mole.

[0009] That is, the ultraviolet and near infrared shielding coating composition of the present invention contains the above-mentioned components (a) to (d), and also contains the component (a) and the component (b) in a specific molar ratio, specifically, a molar ratio in which the molar ratio of the component (b) / the component (a) falls within the range of 0.02 to 1.0. By containing the components (a) and (b) in the above-mentioned specific ratio, the ultraviolet / near infrared shielding coating composition of the present invention can stably disperse the organic ultraviolet absorber (c) and the conductive metal oxide (d) in both the coating composition before curing and the coating layer after curing without requiring a specific surfactant or the like, thereby realizing high versatility and achieving the remarkable technical effects of realizing a coating solution with good stability and a coating film with excellent transparency. The mechanism by which the inclusion of component (a) (silane compound containing an amino group) and component (b) (boron compound) in the specific ratio enables the stably dispersing of (c) the organic ultraviolet absorber and (d) the conductive metal oxide is not necessarily clear, but is presumed to have some relationship to the following factors.

[0010] The ultraviolet-near infrared shielding coating composition of the present invention contains the above-mentioned (a) component (silane compound containing an amino group) and (b) component (boron compound) as essential components in a specific ratio. The ultraviolet-near infrared shielding coating layer obtained by curing the ultraviolet-near infrared shielding coating composition of the present invention usually contains a compound at least partially containing a chemical structure obtained by reacting the (a) component and the (b) component. In addition, the ultraviolet-near infrared shielding coating composition of the present invention may be partially reacted with the (a) component and the (b) component even before curing, and may contain a reaction product of the (a) component and the (b) component in part. The chemical structure obtained by reacting the above-mentioned (a) component (silane compound containing an amino group) and (b) component (boron compound) in a specific ratio often forms a polymer structure. Typically, the (b) boron compound acts as a crosslinking agent via the amino group in the (a) silane compound containing an amino group, polymerizing these components to form a polymer structure having a constitutional unit derived from the (a) silane compound containing an amino group and a constitutional unit derived from the (b) boron compound. The specific structure such as the crosslink density of such a polymer structure changes depending on the ratio of the (a) component and the (b) component, and it is estimated that when the molar ratio of the (b) component / (a) component is within the range of 0.02 to 1.0, a polymer structure suitable for dispersing the (c) organic ultraviolet absorber and the (d) conductive metal oxide can be formed.

[0011] The molar ratio of component (b) / component (a) is preferably from 0.1 to 0.75 mol, and particularly preferably from 0.2 to 0.59 mol. From the viewpoint of effectively dispersing the above-mentioned components (c) and (d), as well as from the viewpoint of effectively suppressing problems such as insufficient solidification and defects in the formation of a coating film, it is preferable that the molar ratio of component (b) / component (a) be equal to or greater than the above-mentioned lower limit, and from the viewpoint of effectively suppressing problems such as component (b) remaining without dissolving in component (a) and problems such as solution stability, it is preferable that the molar ratio of component (b) / component (a) be equal to or less than the above-mentioned upper limit. The molar ratio of component (b) / component (a) can be adjusted / specified by the mixing ratio of each component when preparing the coating composition, or, for an already prepared coating composition, can be specified by chemical analysis such as gravimetric analysis.

[0012] (a) Silane compounds containing amino groups The component (a) used in the present invention is a silane compound containing an amino group and having a specific structure represented by the following formula: R 4-n -Si-(OR') n -(I) (In the formula, R represents an amino group-containing organic group, R' represents a methyl group, an ethyl group, or a propyl group, and n represents an integer selected from 1 to 3.)

[0013] Here, R represents an organic group containing an amino group, and examples thereof include, but are not limited to, monoaminomethyl, diaminomethyl, triaminomethyl, monoaminoethyl, diaminoethyl, triaminoethyl, monoaminopropyl, diaminopropyl, triaminopropyl, monoaminobutyl, diaminobutyl, triaminobutyl, and organic groups having an alkyl group or aryl group having a carbon number greater than these. γ-Aminopropyl and aminoethylaminopropyl are particularly preferred, and γ-aminopropyl is the most preferred.

[0014] In component (a), R' represents a methyl group, an ethyl group, or a propyl group, of which methyl and ethyl groups are preferred.

[0015] In the component (a), n represents an integer selected from 1 to 3. Of these, n is preferably 2 to 3, and n is particularly preferably 3. Therefore, as the component (a), γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, and the like are particularly preferred.

[0016] As long as the molar ratio of component (b) / component (a) is within the above-mentioned numerical range, there is no particular limitation on the amount of component (a) used; however, it is preferable to use 0.5 to 25 mass %, and particularly preferable to use 2 to 15 mass %, based on the mass of the entire coating composition.

[0017] (b) Boron compounds The component (b) used in the present invention is H 3 BO 3 and B. 2 O 3 The component (b) is preferably at least one boron compound selected from the group consisting of H 3BO 3 It is. As long as the molar ratio of component (b) / component (a) is within the above-mentioned numerical range, there is no particular limitation on the amount of component (a) used; however, it is preferable to use 0.04 to 1.2 mass%, and particularly preferable to use 0.1 to 0.9 mass%, based on the total mass of the coating composition.

[0018] The mixing conditions (temperature, mixing time, mixing method, etc.) when reacting (a) a silane compound containing an amino group with (b) a boron compound can be appropriately selected. Under normal room temperature conditions, it becomes a transparent, viscous liquid and solidifies in a few minutes to a few tens of minutes. Since the solidification time and the viscosity and rigidity of the resulting reaction product vary depending on the proportion of the boron compound, it is preferable to adjust these conditions appropriately depending on other components such as (c) an organic ultraviolet absorber and (d) a conductive metal oxide, as well as the physical properties and intended use of the reaction product or coating to be obtained.

[0019] The boron compound (b) can be used in the form of an alcohol solution of the boron compound dissolved in an alcohol having 1 to 7 carbon atoms. Examples of the alcohol having 1 to 7 carbon atoms include methyl alcohol, ethyl alcohol, various propyl alcohols, various butyl alcohols, and glycerin, with methyl alcohol, ethyl alcohol, and isopropyl alcohol being preferred. By using the alcohol solution, the time required to dissolve the (b) component in the (a) component can be shortened. In terms of handling, it is preferable that the concentration of the boron compound in the alcohol is high.

[0020] In the preferred embodiment, the reaction product of components (a) and (b) is preferably a reaction product obtained by reacting components (a) and (b) without a step of hydrolysis by adding water. In this case, since no step of hydrolysis by adding water is required, no complicated steps such as sol-gel formation are required, and the reaction product can be produced without a long time.

[0021] (c) Organic UV absorbers The organic ultraviolet absorber (c) used in the present invention may be any organic chemical substance having ultraviolet absorbing ability, and other restrictions are not particularly imposed, but from the viewpoint of easy availability, it is preferable to use the organic ultraviolet absorber that has been conventionally used. More specifically, it can be benzotriazole-based compounds, triazine-based compounds, benzophenone-based compounds, oxybenzophenone-based compounds, salicylic acid ester-based compounds, cyanoacrylate-based compounds, etc., and among them, it is preferable to use benzotriazole-based compounds, triazine-based compounds, benzophenone-based compounds, etc.

[0022] Benzotriazole-based UV absorbers include 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN 928, manufactured by BASF), 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (TINUVIN PS, manufactured by BASF), ester compound of benzenepropanoic acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy (C7-9 side chain and linear alkyl) (TINUVIN 384-2, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN 900, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN 928, manufactured by BASF), methyl-3-(3-(2H-benzotriazol-2-yl)-5-t-butyl-4-hydroxyphenyl)propionate / polyethylene glycol 300 reaction product (TINUVIN 1130, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-p-cresol (TINUVIN P, manufactured by BASF), 2(2H-benzotriazol-2-yl)-4-6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN 234, manufactured by BASF), 2-[5-chloro(2H)-benzotriazol-2-yl]-4-methyl-6-(tert-butyl)phenol (TINUVIN 326, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (TINUVIN 328, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN 329, manufactured by BASF), reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate with polyethylene glycol 300 (TINUVIN 213, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (TINUVIN 571, manufactured by BASF), etc. can be mentioned.

[0023] Specific examples of triazine-based ultraviolet absorbers include 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (Tinosorb S, manufactured by BASF), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine (TINUVIN 460, manufactured by BASF), and the reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and [(C10-C16 (mainly C12-C13) alkyloxy)methyl]oxirane (TINUVIN 400, manufactured by BASF), 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), reaction product of 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine with (2-ethylhexyl)-glycidic acid ester (TINUVIN 405, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol (TINUVIN 1577, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]-phenol (ADK STAB LA46, manufactured by ADEKA), 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine (TINUVIN 479, manufactured by BASF), and the like.

[0024] Examples of the benzophenone and oxybenzophenone ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (anhydrous and trihydrate), 2-hydroxy-4-octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, and 2,2'-dihydroxy-4,4-dimethoxybenzophenone.

[0025] The maximum absorption wavelength in the absorption spectrum of the (c) organic ultraviolet absorber is preferably in the wavelength range of 300 to 400 nm, and more preferably in the wavelength range of 320 to 380 nm. (c) The organic ultraviolet absorbents may be used alone or in combination of two or more. (c) The amount of organic UV absorber used is not particularly limited, but it is preferable to use 0.5 to 5.0 mass% based on the total mass of the coating composition, based on the active ingredient, and it is particularly preferable to use 1.0 to 4.0 mass%. By setting the amount of the organic UV absorber (c) added within the above range, the UV absorbing function can be fully exhibited, and problems are unlikely to occur in the appearance of the coating composition and the coating layer obtained therefrom.

[0026] (d) Conductive metal oxide The component (d) used in the present invention is a conductive metal oxide. The conductive metal oxide of the component (d) is a (near) infrared ray blocking material, and the addition of the component (d) can effectively block infrared rays, particularly near infrared rays.

[0027] The conductive metal oxide of component (d) in the present invention is not limited as long as it is a metal oxide having electrical conductivity, and examples thereof include an oxide of at least one metal selected from Au, Ag, Ni, Cu, In, Sn, and Sb, and preferably at least one oxide selected from the group consisting of ITO (indium tin oxide) and ATO (antimony tin oxide).

[0028] In order for the coating to be transparent to visible light, it is desirable that the reflection and absorption of visible light is sufficiently small, and that scattering of visible light is as small as possible. Therefore, it is particularly preferable that the (d) conductive metal oxide is an ultrafine particle having an average particle size of less than 1 / 2 the wavelength of visible light, i.e., less than 200 nm, in order to reduce scattering.

[0029] The transparency of the film obtained from the coating composition in visible light is judged by turbidity (the ratio of scattered light components to the total transmitted light), and since a turbidity of more than 10% makes the film feel cloudy, it is preferable to keep the turbidity at 10% or less in order to maintain transparency. In order to achieve such a turbidity of 10% or less, when using particles with a refractive index of about 2, such as ultrafine particles of ITO (indium tin oxide) or ATO (antimony tin oxide), it is preferable to use particles dispersed with an average particle size of 100 nm or less. However, if the average particle size is made too small, the transparency will be high, but the blocking ability of near-infrared rays may decrease, so in order to obtain a certain level of blocking ability of near-infrared rays, it is preferable to keep the dispersed particle size at 10 nm or more while dispersing the ultrafine particles appropriately. Therefore, it is preferable to use the average particle size adjusted to an appropriate range, taking into consideration the balance between transparency in visible light and blocking ability of near-infrared rays.

[0030] The amount of the conductive metal oxide (d) used in the present invention is not particularly limited, but is preferably 1 to 30 parts by mass, more preferably 5 to 25 parts by mass, and even more preferably 10 to 20 parts by mass, based on 100 parts by mass of the entire ultraviolet and near infrared shielding coating composition.

[0031] In the present invention, in addition to the conductive metal oxide of the component (d), a near-infrared absorbing dye may be used in combination. In this case, the near-infrared absorbing dye is not particularly limited as long as it is a dye having near-infrared absorbing ability, and for example, at least one near-infrared absorbing dye selected from azo-based, aluminum-based, anthraquinone-based, cyanine-based, diimonium-based, diol metal complex-based, nosqualylium-based, and phthalocyanine-based near-infrared absorbing dyes can be mentioned. Among them, diimonium-based and phthalocyanine-based near-infrared absorbing dyes are preferred. Examples of such near-infrared absorbing dyes include [bis(4-t-butyl-1,2-dithiophenolate)copper-tetra-n-butylammonium] (BBT manufactured by Sumitomo Seika Chemicals Co., Ltd.), 1,1,5,5-tetrakis[4-(diethylamino)phenyl]-1,4-pentadiene-3-ylium-P-toluenesulfonate (Karenz IR-T manufactured by Showa Denko KK), and phthalocyanine compounds (TKR-2040 manufactured by Yamamoto Kasei Co., Ltd.).

[0032] (e) Silane Compounds Containing Organic Functional Groups The ultraviolet and near infrared shielding coating composition of the present invention may preferably further contain (e) an organic functional group-containing silane compound (excluding those corresponding to the component (a)). Therefore, the polymeric substance that can be formed by the reaction of the coating composition of the present embodiment may have a structure in which the polymeric structure that is the reaction product of the above-mentioned components (a) and (b) is further modified with an organic functional group-containing silane compound (e). That is, an organic functional group-containing silane compound (component (e)) can be added during or after the reaction of components (a) and (b). By adding an organic functional group-containing silane compound (e), preferably a metal alkoxide, it is possible to appropriately adjust the polymer structure and increase the content of metal salt in the resulting reaction product, thereby further improving the mechanical properties, chemical properties, etc., and also to make the product in a viscous liquid state similar to that when component (e) is not used, so that the properties and physical properties of the coating can be appropriately adjusted depending on the application.

[0033] In this embodiment, (e) the organic functional group-containing silane compound is preferably an alkoxy group-containing silane compound (hereinafter also referred to as "metal alkoxide"). From the viewpoint of adjusting the properties and physical properties of the coating, it is preferable to use an alkoxy group-containing silane compound. On the other hand, from the viewpoint of realizing good substrate adhesion, an epoxy group-containing silane compound can also be used. Metal alkoxides preferably used as component (e) exclude compounds that fall under component (a) above (silane compounds having a specific structure and containing an amino group), but no other restrictions apply. Compounds that are generally classified as metal alkoxides, i.e., compounds having at least one metal atom and at least one alkoxy group, can be used as metal alkoxides as long as they do not fall under component (a) above.

[0034] Metals of the metal alkoxide preferably used as the component (e) include, in addition to Si, Ta, Nb, Ti, Zr, Al, Ge, B, Na, Ga, Ce, V, Ta, P, Sb, etc., but are not limited thereto. Si, Ti, and Zr are preferable because of the ease of forming the alkoxide, and since the component (e) is preferably liquid, Si and Ti are particularly preferable from the viewpoint of realizing this. Examples of the alkoxide (alkoxy group) of the metal alkoxide include methoxy, ethoxy, propoxy, butoxy, and alkoxy groups having a carbon number of methoxy, ethoxy, propoxy, and butoxy, and more preferable are methoxy and ethoxy. Examples of particularly preferable metal alkoxides include tetramethoxysilane and tetraethoxysilane. The metal alkoxide may be a polymer, and for example, a pentamer of tetraethoxysilane can be suitably used. A monomer and a pentamer may be used in combination.

[0035] There are no particular limitations on the epoxy group-containing silane compound preferably used as component (e), but a compound having an alkoxy group such as methoxy, ethoxy, propoxy, or butoxy is preferred, and the epoxy group is preferably present in the form of an epoxy group-containing alkyl group such as a glycidoxypropyl group or an epoxycyclohexyl group. More specifically, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, etc. are particularly preferably used.

[0036] The amount of the organic functional group-containing silane compound (e) used is not particularly limited and can be appropriately set depending on the application and desired properties of the obtained ultraviolet / near infrared shielding coating, but it is preferable to use it in a ratio of 10 moles or less per mole of the component (a). More preferably, it is 0.1 moles to 5 moles per mole of the component (a). By making the amount of the component (e) 0.1 moles or more per mole of the component (a), the effects of adding the component (e), such as improving the substrate adhesion and stably dispersing the component (d) (or the component (c) as desired), can be fully exhibited. In addition, by making the amount of the component (e) 10 moles or less, the occurrence of white turbidity can be effectively suppressed. When the component (e) is an alkoxy group-containing silane compound, the content thereof is preferably from 1 to 30 mass %, and particularly preferably from 2 to 15 mass %, based on the mass of the entire coating composition.

[0037] Synthetic Resin The coating composition of the present invention may further contain a synthetic resin instead of or in addition to the (e) metal alkoxide. That is, a synthetic resin may be added during or after the reaction of the (a) component and the (b) component. By adding a synthetic resin, it is possible to impart crack prevention properties and the like to the resulting coating, and it is possible to improve the durability of the coating layer formed from the coating composition of the present invention.

[0038] The synthetic resin that can be used in this embodiment is not particularly limited, but examples thereof include acrylic resin, epoxy resin, polyester resin, amino resin, urethane resin, and furan resin, and synthetic resins having various degrees of polymerization (molecular weight) can be used. In addition, vinyl ester resin, epoxy acrylate, dipentaerythritol hexaacrylate, and the like can also be preferably used. Among them, it is preferable to use (f) epoxy resin from the viewpoints of properties as a resin such as strength, reactivity with other components, stability, and the like.

[0039] (f) Epoxy resin The coating composition of the present invention may contain, in addition to the essential components, (f) an epoxy resin. The (f) epoxy resin may be incorporated into the polymer structure composed of the above-mentioned (a) and (b) components during curing to form a part of the polymer structure, and may also crosslink the polymer structure to change the chemical structure and physical properties of the reaction product of the (a) and (b) components. By containing the (f) epoxy resin in this way, the coating composition of this embodiment can affect the chemical structure and physical properties of the reaction product that constitutes the cured coating, thereby controlling the reactivity, mechanical properties, etc. of the coating.

[0040] The epoxy resin (f) that can be preferably used in this embodiment is not particularly limited, and any resin classified as an epoxy resin in the art, that is, a thermosetting resin that can be cured by forming a crosslinked network with epoxy groups in a polymer structure, and epoxy resins having various degrees of polymerization (molecular weights) can be used. Among them, at least one epoxy resin selected from the group consisting of glycidyl ether type epoxy resins of bisphenol A or bisphenol F, hydrogenated bisphenol A type epoxy resins, glycidyl ester type epoxy resins, alicyclic epoxy resins, and polyglycol type epoxy resins can be preferably used.

[0041] (f) The amount of epoxy resin added is not particularly limited, and can be appropriately set depending on the application form of the coating and the physical properties required after curing, etc. Assuming that the coating composition is generally used, the amount of the epoxy resin (f) used is preferably 0.01 to 5 g, more preferably 0.1 to 2 g, per 1 g of the component (a). That is, if the amount of the epoxy resin (f) added is not too large, the decrease in hardness tends to be suppressed, and conversely, if it is not too small, chemical durability tends to be easily maintained.

[0042] (g) Organic Solvent From the viewpoints of reaction speed and uniformity, ease of coating application, and the like, it is preferable that the coating composition of the present invention contains (g) an organic solvent. The organic solvent (g) is not particularly limited, and any organic solvent that is liquid at room temperature and capable of dissolving or dispersing each of the above components, particularly components (a) to (d), can be used as appropriate.

[0043] From the viewpoint of affinity with each of the above components, some of which have polar groups, and affinity with the substrate to be coated, it is preferable that the (g) organic solvent is a so-called water-soluble organic solvent, which has a certain polarity and is compatible with water. The water-soluble organic solvent preferably used as component (g) is not particularly limited as long as it acts as a diluent and is water-soluble, but for example, alcohols and esters can be preferably used. Among them, it is preferable to use an organic solvent containing an alcohol having 2 to 5 carbon atoms as component (g). Also, higher molecular weight alcohols such as methoxymethylbutanol (MMB) and 2-ethyl-1-hexanol can be used or combined.

[0044] Only one type of organic solvent may be used, or two or more types may be used in combination. When two or more types are used in combination, a mixed solvent may be formed in advance and then used, or a part of each of the above components may be dissolved or dispersed in each of the two or more solvents and then combined. In particular, a solvent suitable for promoting the reaction between the above components (a) and (b) may differ from a solvent suitable for dispersing / dissolving the above components (c) and (d), and in such a case, the latter embodiment is preferred.

[0045] The amount of the (g) organic solvent used is not particularly limited, and may be appropriately set while taking into consideration the reaction efficiency between the components (a) and (b) and other components, the efficiency and workability in applying the coating, the quality of the resulting coating, and the like. Assuming that ultraviolet and near infrared shielding coatings are generally used, the amount of (g) the organic solvent used is preferably 30 to 90 mass %, and more preferably 40 to 75 mass %, of the entire coating composition.

[0046] (h) Surfactants The ultraviolet and near infrared shielding coating composition of the present invention may further contain (h) a surfactant for the purposes of improving leveling properties for forming a smooth coating layer and improving adhesion to a substrate. The type of surfactant is not particularly limited, and may be appropriately selected depending on the application form of the coating, the affinity with other components, particularly the (g) organic solvent, etc. The (h) surfactant may be any of anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants.

[0047] From the viewpoint of leveling property, penetrability, etc., it is particularly preferable to use a fluorine-based surfactant, a silicone-based surfactant, an alkyl ether-based surfactant, etc. Among them, from the viewpoint of leveling property, etc., it is preferable to use a silicone-based surfactant. Specific examples of preferred silicone surfactants include "VORASURF SZ-1919" manufactured by DOW and "BYK-307" manufactured by BYK Japan. Specific examples of preferred fluorine-based surfactants include the "Surflon" series manufactured by AGC Seimi Chemical Co., Ltd., the "Megafac" series manufactured by DIC Corporation, and the "Ftergent" series manufactured by NEOS Corporation.

[0048] The ultraviolet / near-infrared shielding coating composition of the present invention is a highly versatile coating composition that can stably disperse (c) an organic ultraviolet absorber and (d) a conductive metal oxide without using a phosphate ester surfactant or an acrylic surfactant.

[0049] There is no particular restriction on the amount of surfactant (h) added, and it can be appropriately set depending on the application form of the coating and the physical properties required after curing, etc. Assuming that the coating composition is generally used, the amount of the (h) surfactant used is preferably 0.01 to 5.0 mass %, and particularly preferably 0.1 to 1.0 mass %, of the coating composition.

[0050] (i) Light stabilizers The ultraviolet / near infrared shielding coating composition of the present invention preferably contains (i) a light stabilizer in order to prevent photodeterioration of the formed coating layer or to enhance the ultraviolet absorbing ability of the (c) organic ultraviolet absorber. (i) As the light stabilizer, various compounds having a radical scavenging function can be used, but in practice, hindered amine light stabilizers are preferably used. Hindered amine light stabilizers are commonly known as HALS (hindered amine light stabilizers), and are compounds whose basic structure is a 2,2,6,6-tetramethylpiperidine structure.

[0051] Examples of the hindered amine light stabilizer include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis((2,2,6,6-tetramethyl-4-piperidyl) succinate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, and bis(N-octoxy-2,2,6,6-tetramethyl-4-piperidyl). Sebacate, bis(N-benzyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(N-cyclohexyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) 2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-butylmalonate, bis(1-acryloyl-2,2,6,6-tetramethyl-4-piperidyl) 2,2-bis(3,5-di-t-butyl-4-hydroxybenzyl)-2-butylmalonate, bis(1,2,2,6,6-pentamethyl-4-piperidyl decanedioate, 2,2,6,6-tetramethyl-4-piperidyl Methacrylate, 4-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]-1-[2-(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy)ethyl]-2,2,6,6-tetramethylpiperidine, 2-methyl-2-(2,2,6,6-tetramethyl-4-piperidyl)amino-N-(2,2,6,6-tetramethyl-4-piperidyl)propionyl tetrakis(2,2,6,6-tetramethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, and mixed esters of 1,2,3,4-butanetetracarboxylic acid with 1,2,2,6,6-pentamethyl-4-piperidinol and 1-tridecanol.

[0052] The amount of (i) light stabilizer used is not particularly limited, but is preferably 0.01 to 5.0 mass %, more preferably 0.1 to 1.0 mass %, based on the total mass of the coating composition, and is preferably 0.002 to 10.0 mass parts, more preferably 0.02 to 2.0 mass parts, per 1 mass part of (c) organic ultraviolet absorber.

[0053] In addition to the essential components (a) to (d) and the optional components described above, the ultraviolet and near infrared shielding coating composition of the present invention may contain various additives depending on the application, such as an ultraviolet absorber other than an organic ultraviolet absorber (c) such as zinc oxide, a colorant, an antifungal agent, a photocatalytic material, an antirust agent, an anticorrosive agent, an anti-algae agent, a water repellent, an oil repellent, a conductive material, a substrate wetting agent, a hydrophilic material, and a water absorbing material.

[0054] Ultraviolet and near infrared shielding coating layer and its manufacturing method The ultraviolet and near infrared shielding coating composition of the present invention can be applied onto a substrate and cured to produce an ultraviolet and near infrared shielding coating layer. That is, the method for producing an ultraviolet / near infrared shielding coating layer of this embodiment includes a step of reacting the above-mentioned (a) component and (b) component in the presence of the above-mentioned (c) organic ultraviolet absorber and (d) conductive metal oxide. The step of producing a coating composition may be completed before the step of producing a coating layer, or may be performed immediately before the step of producing a coating layer. When the step of producing a coating composition is performed immediately before the step of producing a coating layer, a two-liquid type coating agent consisting of a first liquid and a second liquid each containing a part of the components of the coating composition may be prepared, and the first liquid and the second liquid may be mixed immediately before the step of producing a coating layer to produce a coating composition. In this case, there is no particular restriction on the components that the first liquid and the second liquid should contain, but it is preferable that the first liquid contains the above-mentioned (a) component, (b) component, etc., and it is preferable that the second liquid contains the above-mentioned (c) component, (d) component, etc. The step of reacting the above component (a) with the component (b) is preferably carried out in (g) an organic solvent. In the step of reacting the above-mentioned components (a) and (b), (e) an organic functional group-containing silane compound (excluding those corresponding to the component (a)), (f) a synthetic resin such as an epoxy resin, (h) a surfactant, etc. may be used in combination.

[0055] In the method for producing an ultraviolet-near infrared shielding coating layer of the present embodiment, the ultraviolet-near infrared shielding coating composition of the present invention can be applied to the surface of a substrate by a method such as dipping, spray coating, roll coating, or brush coating. A coating layer may be formed by one application, or a coating layer may be formed by repeating two or more applications. When a coating layer is formed by repeating two or more applications, the coating composition may be cured after application and then further applied, or the coating may be repeated without curing, and the coating composition may be cured after all applications are completed. Heating is not essential for curing, but heating can shorten the curing time.

[0056] There is no particular limit to the amount of the ultraviolet and near infrared shielding coating composition applied, but the coating amount is determined based on the area of ​​the substrate (100 cm2). 2 The coating amount is preferably 1 g to 50 g, more preferably 2 g to 40 g, and particularly preferably 5.0 g or more per 100 cm2 of substrate area. 2 When the weight is 5.0 g or more per unit area, a sufficiently thick ultraviolet and near infrared shielding coating layer can be formed.

[0057] The thickness of the cured ultraviolet-near infrared shielding coating layer is not particularly limited and can be appropriately set depending on the purpose of the ultraviolet-near infrared shielding coating, the required physical properties, the usage mode of the coated member, etc., but is preferably 0.1 to 20 μm, and particularly preferably 0.5 to 10 μm. The ultraviolet / near infrared shielding coating layer after curing can achieve good ultraviolet shielding ability and preferably good near infrared shielding ability, and for example, it is preferable that the light transmittance at a wavelength of 280 to 380 nm is 20% or less, more preferably 15% or less, particularly preferably 10% or less, and the light transmittance at a wavelength of 780 to 2500 nm is 40% or less. From the viewpoint of realizing a high heat shielding effect, it is preferable to block infrared rays up to about 2500 nm on the long wavelength side, and for example, it is particularly preferable that the light transmittance in the wavelength range of 780 to 2500 nm is 35% or less.

[0058] The substrate on which the ultraviolet / near-infrared shielding coating layer of the present embodiment is formed is not particularly limited, but from the viewpoint of effectively exerting the characteristics of the ultraviolet shielding coating, it is preferable that the layer is formed on a transparent substrate having high visible light transmittance, and it is particularly preferable that the layer is formed on, for example, a glass substrate, a transparent plastic substrate, or a transparent ceramic substrate, but is not limited thereto. The ultraviolet and near infrared shielding coating composition of the present invention can realize high levels of film transparency, ultraviolet shielding function, and near infrared shielding function of the coating obtained from the composition, exceeding the limits of conventional techniques, and therefore can be particularly suitably used for components that are exposed to sunlight but require high visibility, such as window materials for buildings and window materials for transportation machines such as automobiles. EXAMPLES

[0059] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited thereto in any way.

[0060] In the following Examples and Comparative Examples, the physical properties and characteristics were evaluated by the following methods. (Appearance of solution) The appearance of the sample prepared as the coating composition in each Example / Comparative Example was visually observed. (Test piece preparation) The coating composition obtained in each Example / Comparative Example was applied to a glass plate with a roller at about 40 g / m 2Test pieces were prepared by applying a coating amount of 100 g / g and allowing it to cure naturally at 20°C and 60% relative humidity or at room temperature, and the coating transparency, near-infrared, visible light, and ultraviolet light transmittance, turbidity, and tack-free time were evaluated. (Coating film transparency) The test pieces prepared according to the above-mentioned method were visually observed and evaluated according to the following criteria. ○: No cloudiness or opacity, and the other side of the glass is visible. △: There is some cloudiness or opacity, and the other side of the glass is visible. ×: Cloudy or opaque, and the other side of the glass cannot be seen through. (Near infrared transmittance) Using the test piece prepared according to the above-mentioned method, the transmittance of light having a wavelength of 780 nm to 2500 nm was measured with a spectrophotometer. (Visible light transmittance) Using the test piece prepared according to the above-mentioned method, the transmittance of light having a wavelength of 380 nm to 780 nm was measured with a spectrophotometer. (Turbidity) Using the test pieces prepared according to the above-mentioned method, the turbidity under visible light (380 to 780 nm) was measured with a spectrophotometer (manufactured by Hitachi High-Tech Science, model number: UH5700 and φ60 integrating sphere accessory). (UV transmittance) Using the test piece prepared according to the above-mentioned method, the transmittance of light having a wavelength of 280 nm to 380 nm was measured with a spectrophotometer. (Touch dry time) Using the test piece prepared according to the above-mentioned method, the time required for the sample to no longer adhere to the fingertip was measured. (Lightfastness) The test pieces prepared according to the above-mentioned method were irradiated for 275 hours using a metal halide lamp type super UV tester (manufactured by Iwasaki Electric, model number: SUV-W262) and then visually observed for the appearance of the coating film.

[0061] Example 1 Coating compositions were prepared by mixing the components in the mass ratios shown in Table 1 and subjected to the above-mentioned evaluations. During preparation, the boron compound (component (b)) was sufficiently reacted with the silane compounds (components (a) and (e)), and then the other components were added. The results are shown in Table 1. The "molar ratio" shown in Table 1 is the relative number of moles of each component per mole of component (a). The details of each component listed in Table 1 are as follows. (e) Ethyl Silicate 40 Tetraethoxysilane pentamer (average) Ethyl silicate 40 manufactured by Colcoat Co., Ltd. (e) Ethyl silicate 28 Tetraethoxysilane monomer Colcoat Co., Ltd. Ethyl silicate 28 (a) KBE-903 γ-Aminopropyltriethoxysilane Shin-Etsu Chemical Co., Ltd. KBE-903 (b) Boric Acid H 3 BO 3 (f) EX-252 Hydrogenated bisphenol A epoxy resin EX-252 manufactured by Nagase ChemteX Corporation (g) MMB Methoxymethylbutanol (h) VORASURF SZ-1919 Silicone surfactant: DOW VORASURF SZ-1919 (c) Tinuvin384-2 (AI 95%) Benzotriazole UV absorber BASF Tinuvin 384-2 Active substance 95% by mass (c) Tinuvin400 (AI 85%) Hydroxyphenyltriazine UV absorber BASF Tinuvin 400 Active substance 85% by mass (i) Tinuvin249 >NR type hindered amine light stabilizer BASF Tinuvin 249 (d) ATO-MMB dispersion ATO (tin-antimony oxide)-MMB (methoxymethylbutanol) dispersion ATO content 30% Average particle size: 20nm Manufactured by Mitsubishi Materials Corporation

[0062] (Examples 2 to 11, Comparative Examples 1 to 5) Except for changing the composition of each component to that shown in Table 1, coating compositions were prepared in the same manner as in Example 1 and subjected to the above-mentioned evaluations. The results are shown in Table 1.

[0063] [Table 1]

[0064] [Table 2] In each Example that satisfied the conditions of the present invention, a coating solution having good solution appearance and a coating layer having good film transparency as well as sufficient ultraviolet shielding function and near-infrared shielding function were realized. Comparative Examples 1 and 2, in which the molar number of (b) boron compound relative to (a) silane compound containing an amino group did not satisfy the conditions of the present invention, had problems with solution appearance or film transparency. Comparative Examples 3 to 5, in which (c) organic ultraviolet absorber and / or (d) conductive metal oxide were not used, were unable to achieve sufficient ultraviolet shielding function and / or near-infrared shielding function. [Industrial Applicability]

[0065] The ultraviolet and near-infrared shielding coating composition of the present invention has a high degree of freedom in preparation, storage, coating, etc., and is capable of forming a coating layer that has an ultraviolet shielding function and a near-infrared shielding function and is excellent in transparency in visible light. Therefore, the composition can be particularly suitably used in components that are exposed to sunlight but require high visibility, such as window materials for buildings and automobiles, and has high applicability in various industrial fields, such as architecture, construction, transportation machinery such as automobiles, and electrical and electronic equipment.

Claims

1. An ultraviolet and near infrared shielding coating composition comprising the following components (a) to (d): (a) a silane compound containing an amino group represented by the following formula (I): R ４－ｎ -Si-(OR’) ｎ -(I) (wherein R represents an amino group-containing organic group, R' represents a methyl group, an ethyl group, or a propyl group, and n represents an integer selected from 1 to 3); (b) H ３ B.O. ３ and B ２ O ３ at least one boron compound selected from the group consisting of: (c) an organic ultraviolet absorber; (d) conductive metal oxide; (b) the amount of the boron compound relative to 1 mole of the silane compound containing an amino group is 0.02 to 0.75 moles; Substantially free of any phosphate ester surfactant or acrylic surfactant; The ultraviolet and near infrared shielding coating composition.

2. The ultraviolet-near infrared shielding coating composition according to claim 1, wherein the amount of (b) the boron compound per 1 mole of (a) the silane compound containing an amino group is 0.1 to 0.75 moles.

3. The ultraviolet-near infrared shielding coating composition of claim 1, wherein the amount of (b) the boron compound per 1 mole of (a) the silane compound containing an amino group is 0.2 to 0.59 moles.

4. 4. The ultraviolet and near infrared shielding coating composition according to claim 1, wherein the organic ultraviolet absorber (c) is selected from the group consisting of benzotriazole-based compounds, triazine-based compounds, and benzophenone-based compounds.

5. 5. The ultraviolet and near infrared shielding coating composition according to claim 4, wherein the organic ultraviolet absorbing agent (c) is a benzotriazole-based compound or a triazine-based compound.

6. The ultraviolet and near infrared shielding coating composition according to claim 1 , further comprising a light stabilizer.

7. The ultraviolet and near infrared shielding coating composition according to claim 1 , further comprising (e) an organic functional group-containing silane compound (excluding those corresponding to the above component (a)).

8. The ultraviolet / near infrared shielding coating composition according to claim 7, wherein the (e) organofunctional group-containing silane compound comprises an alkoxy group-containing silane compound.

9. 9. The ultraviolet and near infrared shielding coating composition according to claim 1, wherein the conductive metal oxide is at least one oxide selected from the group consisting of ITO (indium tin oxide) and ATO (antimony tin oxide).

10. The ultraviolet-near infrared shielding coating composition according to any one of claims 1 to 9, wherein the amount of the organic ultraviolet absorber (c) added is 0.5 to 5.0 parts by mass, based on 100 parts by mass of the entire ultraviolet-near infrared shielding coating composition.

11. The ultraviolet-near infrared shielding coating composition according to claim 1 , which is substantially free of zinc oxide.

12. A method for producing an ultraviolet and near infrared shielding coating layer, comprising a step of applying the ultraviolet and infrared shielding coating composition according to claim 1 .

13. The method for producing an ultraviolet-near infrared shielding coating layer according to claim 12, wherein a coating layer having a light transmittance of 20% or less at a wavelength of 280 to 380 nm and a light transmittance of 40% or less at a wavelength of 780 to 2500 nm is formed.

14. The method for producing an ultraviolet-near infrared shielding coating layer according to claim 12 or 13, comprising forming a coating layer on a transparent substrate.

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