Primer composition and coated article

Abstract

Provided is a primer composition that contains: (A) a copolymer (A-1) which contains a constituent unit represented by the formula shown below and which does not contain a prescribed ultraviolet radiation-absorbing group (R1 denotes a hydrogen atom or the like, R2 denotes a monovalent hydrocarbon group or the like, R4 denotes a hydrogen atom or the like, R5 and R6 each denote an alkyl group or the like, X2 denotes an alkyleneoxycarbonyl group or the like, n denotes an integer between 1 and 3, and ＊ denotes a bond to an adjacent constituent unit);　a vinyl-based (co)polymer (A-2) which does not contain an alkoxysilyl, does not contain a prescribed ultraviolet radiation-absorbing group, and has a glass transition point of 80°C or higher; an ultraviolet radiation absorber (B); a compound (C) having a cyclic hindered amine structure; inorganic particles (D) having a median diameter of 100 nm or less; and a solvent (E). The (A-1) : (A-2) mass ratio is 3:1 to 1:3.

Description

Primer composition and coated article

[0001] The present invention relates to a primer composition and a coated article. More specifically, the present invention relates to a primer composition and a coated article that can form a coating excellent in visible light transmittance, UV blocking properties, scratch resistance, and long-term weather resistance by coating the surface of an organic resin substrate such as a plastic and then providing a silicone hard coat layer or the like thereon.

[0002] In recent years, transparent materials that are non-shatterproof or more shatter-resistant than glass have become widely used as substitutes for transparent plate glass. For example, plastic substrates, particularly polycarbonate resins, are excellent in transparency, impact resistance, heat resistance, etc., and are currently used as structural substitutes for glass in a variety of applications, such as windows for buildings and vehicles, and instrument covers.

[0003] However, since polycarbonate resin moldings are inferior to glass in terms of surface properties such as scratch resistance and weather resistance, there is a strong demand for improving the surface properties of polycarbonate resin moldings. Recently, there has been a demand for products that can withstand outdoor exposure for 10 years or more, such as vehicle windows and road noise insulation walls.

[0004] As a means for improving the weather resistance of polycarbonate resin molded articles, a method of laminating an acrylic resin film or the like having excellent weather resistance on the surface of a polycarbonate resin substrate, or a method of providing a resin layer containing an ultraviolet absorber on the resin surface by coextrusion, etc. Also, as a method for improving the scratch resistance of polycarbonate resin molded articles, a method of coating with a thermosetting resin such as a polyorganosiloxane or melamine, or a method of coating with a polyfunctional acrylic photocurable resin, has been proposed.

[0005] On the other hand, a method for producing a transparent body that has both weather resistance and scratch resistance is known in which a UV-absorbing transparent substrate is produced by providing a silicone hard coat layer containing colloidal silica via an undercoat layer containing a large amount of UV absorber.

[0006] However, adding a large amount of UV absorber to the undercoat layer has adverse effects such as poor adhesion to the substrate or the silicone hard coat layer formed on top of the undercoat layer, and causing cracks, whitening, or yellowing when used outdoors for a long period of time. Furthermore, there is also the problem that a large amount of UV absorber cannot be added to the silicone hard coat layer on the top surface due to the scratch resistance.

[0007] Furthermore, Patent Documents 1 to 4 report that a multilayer laminated resin article can be obtained that is imparted with weather resistance while maintaining adhesion to a resin substrate by using, as a coating component, a copolymer of a benzotriazole-based ultraviolet-absorbing vinyl monomer or a benzophenone-based ultraviolet-absorbing vinyl monomer, an alkoxysilyl group-containing vinyl monomer, and a vinyl monomer copolymerizable with these monomers.

[0008] In these patent documents, a coated article having scratch resistance and weather resistance is obtained by forming a silicone hard coat layer on a coating film formed using a copolymer-containing paint as a primer. Although the adhesion to the silicone hard coat layer and weather resistance of these coated articles are significantly improved, peeling and cracking of the coating film occur in longer weather resistance tests, and the long-term weather resistance is still insufficient.

[0009] Furthermore, in this field, it is common to use a vinyl copolymer in which an ultraviolet absorber is chemically bonded to a side chain. For example, as disclosed in the comparative example of Patent Document 5, it has been reported that adding a large amount of an ultraviolet absorber that is not chemically bonded to a vinyl copolymer causes a decrease in adhesion between films, a decrease in abrasion resistance, whitening of the coating film, deterioration of weather resistance, etc.

[0010] JP 2001-114841 A JP 2008-120986 A JP 2012-077267 A JP 2016-014132 A JP 2007-231060 A

[0011] The present invention has been made in view of the above circumstances, and aims to provide a primer composition that can form a primer layer that can impart scratch resistance, adhesion, and weather resistance sufficient to withstand long-term outdoor use to a substrate such as an organic resin, in combination with a silicone-based hard coat layer or the like, while maintaining visible light transmittance, and a coated article.

[0012] As a result of intensive research aimed at solving the above-mentioned problems, the present inventors have found that by applying the following primer composition to a substrate such as an organic resin and laminating a silicone-based hard coat layer or the like, a coated article having excellent abrasion resistance, visible light transmittance, adhesion, and weather resistance can be realized, and have completed the present invention.

[0013] That is, the present invention provides: 1. a primer composition containing the following components (A) to (E), in which the mass ratio (A-1):(A-2) of the following component (A-1) to the following component (A-2) is 3:1 to 1:3; (A) the following components (A-1) and (A-2): (A-1) a copolymer containing a structural unit (a) represented by the following formula (1) and a structural unit (b) represented by the following formula (2), and containing no hydroxyphenyltriazine structure, benzophenone structure, or benzotriazole structure: [In formula (1), R 1 represents a hydrogen atom, a halogen atom or a methyl group, R 2 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hydroxyl group, an amino group or an epoxy group and which may have an ether bond, a cyano group, an amide group or -X 1 -R 3 (X 1 is an oxygen atom, a carbonyl group, an oxycarbonyl group, or a carbonyloxy group, and R 3 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hydroxyl group, an amino group or an epoxy group and which may have an ether bond; 4 represents a hydrogen atom or a methyl group, R 5 and R 6 each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms; X 2represents a single bond, an arylene group having 6 to 10 carbon atoms, or an alkyleneoxycarbonyl group having 2 to 12 carbon atoms; n represents an integer of 1 to 3; and an asterisk * indicates a bond to an adjacent structural unit. (A-2) A vinyl (co)polymer having a glass transition point of 80°C or higher that does not contain an alkoxysilyl group and does not contain any of a hydroxyphenyltriazine structure, a benzophenone structure, and a benzotriazole structure: 100 parts by mass in total of components (A-1) and (A-2) (B) One or more ultraviolet absorbers selected from the group consisting of (B-1) hydroxyphenyltriazine compounds, (B-2) benzophenone compounds, and (B-3) benzotriazole compounds: 1 to 30 parts by mass (C) A compound having a cyclic hindered amine structure: 0.5 to 7 parts by mass (D) Inorganic particles having a median diameter of 100 nm or less as measured by a dynamic light scattering method: 3 to 20 parts by mass (E) A solvent: An amount that results in a solids concentration in the composition of 1 to 50% by mass 2. 2. The primer composition according to 1, wherein the structural unit (b) in the component (A-1) is present in an amount of 0.2 to 0.6 mmol / g relative to the total mass of the component (A-1) and the component (A-2); 3. The primer composition according to 1 or 2, wherein the glass transition point of the component (A-1) is 30°C or lower; 4. The primer composition according to any one of 1 to 3, wherein the structural unit (a) in the component (A-1) comprises a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4), and the structural unit (b) comprises a structural unit represented by the following formula (5); (wherein an asterisk * indicates a bond to an adjacent structural unit.) 5. The primer composition according to any one of 1 to 4, wherein the component (B) comprises the component (B-1) and is incorporated in an amount of 1 to 5 parts by mass per 100 parts by mass of the total of the components (A-1) and (A-2), 6. The primer composition according to any one of 1 to 5, wherein the component (D) comprises zinc oxide particles, 7. The primer composition according to any one of 1 to 6, wherein the component (D) comprises silica particles, 8. A coated article having a substrate and a primer layer comprising a cured coating of the primer composition according to any one of 1 to 7, formed on at least one surface of the substrate directly or via one or more other layers, wherein the primer layer has a modulus of elasticity of 1.5 GPa or more, 9. The coated article according to 8, wherein the primer layer has a silicone hard coat layer on the primer layer, 10. The silicone hard coat layer is formed by: (A) a compound represented by the following general formula (6): (R 7 ) m Si(OR 8 ) 4-m (6) (wherein, R 7 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group, and a plurality of R 7 may be bonded to each other to form a linking group, and R 8 each independently represents an alkyl group having 1 to 3 carbon atoms, and m is 0, 1, or 2.) A silicone resin obtained by (co)hydrolyzing and condensing at least one selected from alkoxysilanes represented by the formula (I) and their (partial) hydrolysis condensates, (A) colloidal silica, (C) a curing catalyst, and (D) a solvent. 11. A coated article according to claim 10, wherein the silicone hard coating composition further contains (E) an organic ultraviolet absorber. 12. A coated article according to claim 11, wherein the component (E) is an organic ultraviolet absorber having an alkoxysilyl group. 13. A coated article according to claim 12, wherein the component (E) is an organic ultraviolet absorber represented by the following general formula (7): [In the formula, R 9are each independently a hydrogen atom, a hydroxy group, an alkyl group having 1 to 5 carbon atoms, or a group represented by the following general formula (8), 9 At least one of the groups is a group represented by the following general formula (8): *—O—(CH2) j -SiR 10 k (OR 11 ) 3-k (8) (wherein, R 10 and R 11 each independently represents an alkyl group having 1 to 5 carbon atoms. j represents an integer of 1 to 8, and k represents an integer of 0 to 2. An asterisk * represents a bond to an adjacent atom.) 14. A coated article according to 10, wherein the silicone hard coating composition further contains (f) an inorganic ultraviolet absorber. 15. A coated article according to 14, wherein the component (f) is a core-shell type tetragonal titanium oxide solid solution having a core made of tetragonal titanium oxide solid solution particles containing tin and manganese as a solid solution and a silicon oxide shell surrounding the core, the median diameter of the core-shell type tetragonal titanium oxide solid solution measured by dynamic light scattering is 50 nm or less, the amount of tin in solid solution is in a molar ratio to titanium (Ti / Sn) of 10 to 1,000, and the amount of manganese in solid solution is in a molar ratio to titanium (Ti / Mn) of 10 to 1,000. 16. 16. The coated article according to any one of 8 to 15, wherein the substrate is an organic resin substrate.

[0014] According to the present invention, by combining with a silicone-based hard coat layer or the like, it is possible to impart scratch resistance, adhesion, and weather resistance sufficient to withstand long-term outdoor use to a substrate such as an organic resin while maintaining visible light transmittance, and therefore the present invention is suitable for use in coating resin members used in vehicle windows, sound insulation walls for buildings and roads, etc.

[0015] The present invention will be described in detail below. <Primer Composition> The primer composition according to the present invention contains the following components (A) to (E): (A) Components (A-1) and (A-2) below: (A-1) A copolymer containing a structural unit (a) represented by the following formula (1) and a structural unit (b) represented by the following formula (2), and not containing a specified ultraviolet-absorbing group; (A-2) A vinyl (co)polymer having a glass transition point of 80°C or higher, not containing an alkoxysilyl group, and not containing a specified ultraviolet-absorbing group; (B) One or more ultraviolet absorbers selected from the group consisting of (B-1) hydroxyphenyltriazine compounds, (B-2) benzophenone compounds, and (B-3) benzotriazole compounds; (C) A compound having a cyclic hindered amine structure; (D) Inorganic particles having a median diameter of 100 nm or less as measured by dynamic light scattering; (E) A solvent

[0016] [Component (A)] [1] Component (A-1) The component (A-1) is a copolymer containing a structural unit (a) represented by the following formula (1) and a structural unit (b) represented by the following formula (2), and does not contain a specified ultraviolet-absorbing group.

[0017] (wherein the asterisk * indicates a bond to an adjacent building block.)

[0018] (1) Structural unit (a) In formula (1), R 1 represents a hydrogen atom, a halogen atom such as a chlorine atom, or a methyl group, and is preferably a hydrogen atom or a methyl group.

[0019] R 2 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hydroxyl group, an amino group or an epoxy group and which may have an ether bond, a cyano group, an amide group or -X 1 -R 3 (X 1 is an oxygen atom, a carbonyl group, an oxycarbonyl group, or a carbonyloxy group, and R 3 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hydroxyl group, an amino group or an epoxy group and which may have an ether bond.

[0020] R2 The monovalent hydrocarbon group R may be linear, branched, or cyclic, and examples thereof include an alkyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 8 carbon atoms; an alicyclic hydrocarbon group having 3 to 20 carbon atoms, preferably 3 to 10 carbon atoms, and more preferably 3 to 8 carbon atoms; an aryl group having 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms; and an aralkyl group having 7 to 20 carbon atoms, preferably 7 to 10 carbon atoms. 2 Specific examples of the monovalent hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, n-heptyl, isoheptyl, 2-ethylhexyl, n-octyl, isooctyl, n-nonyl, isononyl, n-decyl, isodecyl, n-undecyl, n-dodecyl, lauryl, palmityl, and stearyl groups; alicyclic hydrocarbon groups such as cyclohexyl, 4-methylcyclohexyl, 4-t-butylcyclohexyl, isobornyl, dicyclopentanyl, and dicyclopentenyloxyethyl groups; aryl groups such as phenyl, 1-naphthyl, and 2-naphthyl groups; and aralkyl groups such as benzyl and phenethyl groups.

[0021] In addition, some or all of the hydrogen atoms of these groups may be substituted with hydroxyl groups, amino groups, epoxy groups, etc., and they may also have an ether bond. Specific examples thereof include (poly)ether groups such as 2-methoxyethyl, 2-methoxypropyl, 3-methoxypropyl, 2-methoxybutyl, 3-methoxybutyl, 4-methoxybutyl, methoxypolyethylene glycol group (the number of ethylene glycol units is preferably, for example, 2 to 20), and methoxypolypropylene glycol group (the number of propylene glycol units is preferably, for example, 2 to 20); hydroxyalkyl groups such as 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 2-hydroxybutyl, 3-hydroxybutyl, and 4-hydroxybutyl; hydroxypolyether groups such as polyethylene glycol group (the number of ethylene glycol units is preferably, for example, 2 to 20), and polypropylene glycol group (the number of propylene glycol units is preferably, for example, 2 to 20); aminoalkyl groups such as 2-aminoethyl, 2-(N-methylamino)ethyl, 2-(N,N-dimethylamino)ethyl, 2-(N-ethylamino)ethyl, 2-(N,N-diethylamino)ethyl, 3-(N,N-dimethylamino)propyl, and 4-(N,N-dimethylamino)butyl; and epoxyalkyl groups such as a glycidyl group.

[0022] R 2 The amide group may have an alkylene group, and may have a substituent on the nitrogen atom such as an alkyl group, a hydroxyalkyl group, or a dialkylaminoalkyl group. Specific examples thereof include N-methylamide, N,N-dimethylamide, N-ethylamide, N,N-diethylamide, N-methoxyamide, N,N-dimethoxyamide, N-ethoxyamide, N,N-diethoxyamide, diacetoneamide, N-methylolamide, N-(2-hydroxyethyl)amide, N,N-dimethylaminomethylamide, and N-(2-dimethylamino)ethylamide.

[0023] -X 1 -R 3 In the group represented by 3 The monovalent hydrocarbon group having 1 to 20 carbon atoms is R2 Specific examples thereof include the same groups as those exemplified by R 2 The same groups as those exemplified in -X are included. 1 -R 3 The group represented by X 1 and R 3 and groups in any combination thereof, among which methoxycarbonyl, ethoxycarbonyl, isopropoxycarbonyl, n-butoxycarbonyl, isobutoxycarbonyl, n-hexyloxycarbonyl, 2-ethylhexyloxycarbonyl, isononyloxycarbonyl, lauryloxycarbonyl, cyclohexyloxycarbonyl, 4-methylcyclohexyloxycarbonyl, 4-t-butylcyclohexyloxycarbonyl, isobornyloxycarbonyl, dicyclopentanyloxycarbonyl, dicyclopentenyloxyethyloxycarbonyl, and glycidyloxycarbonyl groups are preferred.

[0024] Examples of the structural unit (a) represented by the above formula (1) include those represented by the following formula: (wherein the asterisk * indicates a bond to an adjacent building block.)

[0025] (2) Structural unit (b) In formula (2), R 4 represents a hydrogen atom or a methyl group. 5 and R 6 R each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, preferably 1 to 8 carbon atoms, or an aryl group having 6 to 10 carbon atoms, preferably 6 to 8 carbon atoms. 5 and R 6 Specific examples of the alkyl group having 1 to 10 carbon atoms represented by the formula (I) include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, n-heptyl, isoheptyl, 2-ethylhexyl, n-octyl, isooctyl, n-nonyl, isononyl, and n-decyl groups, with methyl and ethyl groups being preferred. 5 and R 6Examples of the aryl group having 6 to 10 carbon atoms include phenyl, 1-naphthyl, and 2-naphthyl groups, with the phenyl group being preferred.

[0026] X 2 represents a single bond, an arylene group having 6 to 10 carbon atoms, or an alkyleneoxycarbonyl group having 2 to 12 carbon atoms, preferably 2 to 10 carbon atoms. 2 The alkyleneoxycarbonyl group is —CO—O—(CH2) i -* (where i is an integer of 1 to 11, preferably 1 to 9, more preferably 1 to 3, and the asterisk * indicates a bond to an adjacent silicon atom). n is an integer of 1 to 3, preferably 3.

[0027] Examples of the structural unit (b) represented by the above formula (2) include those represented by the following formula:

[0028] (wherein the asterisk * indicates a bond to an adjacent building block.)

[0029] For the component (A-1), it is particularly preferable that the structural unit (a) includes a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4), and that the structural unit (b) includes a structural unit represented by the following formula (5).

[0030] (wherein the asterisk * indicates a bond to an adjacent building block.)

[0031] The content of structural unit (b) in component (A-1) is preferably 0.2 to 0.6 mmol / g based on the total content of component (A-1) and component (A-2) described below. Within this range, the presence of alkoxysilyl groups and the like will form crosslinks between components (A-1) themselves and with component (D) described below, improving the strength of the coating film and further improving interlayer adhesion and weather resistance through reaction with siloxane in the silicone hard coat layer formed on the primer layer.

[0032] The structural units contained in the component (A-1) may be arranged in any order, and the component (A-1) may be an alternating copolymer, a random copolymer, or a block copolymer.

[0033] The glass transition point of component (A-1) is preferably 30°C or lower, more preferably 20°C or lower. A glass transition point of 30°C or lower is preferred because it provides good coatability and adhesion to the substrate. In the present invention, the glass transition point can be measured, for example, based on JIS-K7121:2012. Generally, the phase transition of a polymer is in the order of liquid → rubber state → glass state, and therefore the glass transition temperature, which is the transition temperature from the rubber state to the glass state, is lower than the melting point, which is the transition temperature from the liquid → rubber state. Therefore, if the copolymer is liquid at temperatures of 30°C or lower (the melting point is 30°C or lower), it can be determined that the glass transition point is necessarily 30°C or lower.

[0034] The weight average molecular weight of the component (A-1) in terms of polystyrene, as determined by gel permeation chromatography (GPC), is preferably 5,000 to 1,000,000, and more preferably 30,000 to 500,000, from the viewpoints of handleability, appearance, and adhesiveness. The component (A-1) may be used alone, or two or more types may be used in combination.

[0035] The component (A-1) can be obtained by copolymerizing the monomer that constitutes the structural unit (a) and the monomer that constitutes the structural unit (b) by polymerization. The polymerization conditions, such as reaction temperature, time, and polymerization initiator, are not particularly limited, and may be carried out under known conditions. For example, the component (A-1) can be easily obtained by using a radical polymerization initiator selected from peroxides such as dicumyl peroxide and benzoyl peroxide, and azo compounds such as azobisisobutyronitrile, and reacting at 50 to 150°C, particularly 70 to 120°C, for 1 to 10 hours, particularly 3 to 8 hours.

[0036] Examples of the monomer that can be polymerized to form the structural unit (a) include (meth)acrylic acid, (meth)acrylic acid esters, (meth)acrylonitrile, (meth)acrylamide, alkyl vinyl ethers, alkyl vinyl esters, styrene, and derivatives thereof. In the present invention, (meth)acrylic means acrylic and / or methacrylic.

[0037] Specific examples of (meth)acrylic acid esters and derivatives thereof include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, n-hexyl (meth)acrylate, isohexyl (meth)acrylate, n-heptyl (meth)acrylate, isoheptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, (Meth)acrylic acid esters of monohydric alcohols such as n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-undecyl (meth)acrylate, n-dodecyl (meth)acrylate, lauryl (meth)acrylate, palmityl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, 4-methylcyclohexyl (meth)acrylate, 4-t-butylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and benzyl (meth)acrylate; 2-methoxyethyl (meth)acrylate, 2-methoxypropyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 4-methoxybutyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate (the number of ethylene glycol units is preferably, for example, 2 to 20), methoxypolypropylene glycol (meth)acrylate (the number of propylene glycol units is preferably, for example, 2 to 20).(meth)acrylic acid esters of alkoxy (poly)alkylene glycols such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycerin mono(meth)acrylate, pentaerythritol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate (the number of ethylene glycol units is preferably, for example, 2 to 20), and polypropylene glycol mono(meth)acrylate (the number of propylene glycol units is preferably, for example, 2 to 20); Examples thereof include amino group-containing (meth)acrylic acid esters such as 2-aminoethyl (meth)acrylate, 2-(N-methylamino)ethyl (meth)acrylate, 2-(N,N-dimethylamino)ethyl (meth)acrylate, 2-(N-ethylamino)ethyl (meth)acrylate, 2-(N,N-diethylamino)ethyl (meth)acrylate, 3-(N,N-dimethylamino)propyl (meth)acrylate, and 4-(N,N-dimethylamino)butyl (meth)acrylate; and epoxy group-containing (meth)acrylic acid esters such as glycidyl (meth)acrylate.

[0038] Specific examples of the derivatives of (meth)acrylonitrile include α-chloroacrylonitrile, α-chloromethylacrylonitrile, α-trifluoromethylacrylonitrile, α-methoxyacrylonitrile, α-ethoxyacrylonitrile, vinylidene cyanide, and the like.

[0039] Specific examples of the (meth)acrylamide derivative include N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-ethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-methoxy(meth)acrylamide, N,N-dimethoxy(meth)acrylamide, N-ethoxy(meth)acrylamide, N,N-diethoxy(meth)acrylamide, diacetone(meth)acrylamide, N-methylol(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N,N-dimethylaminomethyl(meth)acrylamide, and N-(2-dimethylamino)ethyl(meth)acrylamide.

[0040] Specific examples of alkyl vinyl ethers include methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, and hexyl vinyl ether.

[0041] Specific examples of alkyl vinyl esters include vinyl formate, vinyl acetate, vinyl acrylate, vinyl butyrate, vinyl caproate, and vinyl stearate.

[0042] Specific examples of styrene and its derivatives include styrene, α-methylstyrene, and vinyltoluene.

[0043] Of these monomers, (meth)acrylic acid esters are preferred, and particularly preferred are methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, lauryl (meth)acrylate, cyclohexyl (meth)acrylate, 4-methylcyclohexyl (meth)acrylate, 4-t-butylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, glycidyl (meth)acrylate, etc. Such monomers can be used alone or in combination of two or more.

[0044] Examples of the monomer that polymerizes to form the structural unit (b) include methacryloxymethyltrimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxyundecyltrimethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, methacryloxypropyltriethoxysilane, acryloxypropyltrimethoxysilane, acryloxypropylmethyldimethoxysilane, acryloxypropyldimethylmethoxysilane, acryloxypropyltriethoxysilane, acryloxymethyltrimethoxysilane, acryloxyundecyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, allyltrimethoxysilane, styryltrimethoxysilane, styrylmethyldimethoxysilane, and styryltriethoxysilane. Among these, methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, acryloxypropyltrimethoxysilane, and acryloxypropylmethyldimethoxysilane are preferred in terms of availability, ease of handling, crosslinking density, reactivity, and the like.

[0045] [2] Component (A-2) Component (A-2) is a vinyl (co)polymer that does not contain an alkoxysilyl group or a specific UV-absorbing group and has a glass transition point of 80°C or higher. The glass transition point of component (A-2) is preferably 90°C or higher, more preferably 100°C or higher. A glass transition point below 80°C can result in poor appearance, such as whitening of the coating, and insufficient adhesion, durability, and weather resistance can be achieved. The glass transition point can be measured in accordance with JIS-K7121:2012. The inclusion of a vinyl (co)polymer with a high glass transition point improves the elastic modulus of the coating. The elastic modulus of the coating correlates with the mobility of the molecules contained therein; a higher elastic modulus reduces molecular mobility, suppressing the migration of low-molecular-weight components such as UV absorbers within the coating over time and reducing the tendency for aggregation and migration of the components to the coating surface. As a result, whitening of the appearance and a decrease in adhesion are suppressed.

[0046] The component (A-2) can be obtained by (co)polymerizing one or more vinyl monomers having a vinyl-polymerizable functional group, such as an alkenyl group, an alkenyloxy group, a (meth)acryloxy group, an (α-methyl)styryl group, etc. The polymerization conditions, such as the reaction temperature, time, and polymerization initiator, are not particularly limited and may be carried out under known conditions. For example, the component (A-2) can be easily obtained by using a radical polymerization initiator selected from peroxides such as dicumyl peroxide and benzoyl peroxide, or azo compounds such as azobisisobutyronitrile, and reacting at 50 to 150°C, particularly 70 to 120°C, for 1 to 10 hours, particularly 3 to 8 hours.

[0047] Examples of vinyl monomers that serve as raw materials for the component (A-2) include the same monomers that serve as raw materials for the structural unit (a) in the component (A-1), such as (meth)acrylic acid, (meth)acrylic acid esters, (meth)acrylonitrile, (meth)acrylamide, alkyl vinyl ethers, alkyl vinyl esters, styrene, and derivatives thereof, and specific examples of these monomers are the same as those given as examples of the monomers that serve as raw materials for the structural unit (a) in the component (A-1). In addition to these, poly(meth)acrylic acid esters of polyhydric alcohols such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, glycerin di(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tetra(meth)acrylate, 1,4-cyclohexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate (the number of ethylene glycol units is preferably, for example, 2 to 20), and polypropylene glycol di(meth)acrylate (the number of propylene glycol units is preferably, for example, 2 to 20); (Poly)esters of non-polymerizable polybasic acids and hydroxyalkyl (meth)acrylates, such as mono[2-(meth)acryloyloxyethyl] succinate, di[2-(meth)acryloyloxyethyl] succinate, mono[2-(meth)acryloyloxyethyl] adipate, di[2-(meth)acryloyloxyethyl] adipate, mono[2-(meth)acryloyloxyethyl] phthalate, and di[2-(meth)acryloyloxyethyl] phthalate; and bis(meth)acrylamides, such as N,N'-methylenebis(meth)acrylamide and N,N'-ethylenebis(meth)acrylamide.

[0048] Of these monomers, (meth)acrylic acid esters are preferred, with methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, lauryl (meth)acrylate, cyclohexyl (meth)acrylate, 4-methylcyclohexyl (meth)acrylate, 4-t-butylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and the like being more preferred, with methyl (meth)acrylate being even more preferred. The vinyl-based monomer serving as the raw material for component (A-2) may use either one of these monomers alone or two or more of them in combination.

[0049] As the component (A-2), a commercially available product may be used, and specific examples thereof include (meth)acrylic acid ester resins such as DIANAL (registered trademark) BR-85, BR-88, and LR-1065 manufactured by Mitsubishi Rayon Co., Ltd. The component (A-2) may be used alone or in combination of two or more types.

[0050] The weight average molecular weight of component (A-2) as calculated as polystyrene by GPC is preferably 50,000 to 1,000,000, and more preferably 60,000 to 800,000. If the molecular weight is too large, the viscosity may become too high, making synthesis and handling difficult, while if the molecular weight is too small, poor appearance such as whitening of the coating may occur, and sufficient adhesion, durability, and weather resistance may not be obtained.

[0051] The weight average molecular weight of component (A-1) and component (A-2) as a whole, as calculated in terms of polystyrene, as determined by GPC, is preferably 6,000 to 1,000,000, and more preferably 50,000 to 800,000. If the molecular weight is too large, the viscosity may become too high, making synthesis or handling difficult, while if the molecular weight is too small, poor appearance such as whitening of the coating may occur, and sufficient adhesion, durability, and weather resistance may not be obtained.

[0052] The mass mixing ratio of component (A-1) to component (A-2) is (A-1):(A-2) = 3:1 to 1:3, preferably (A-1):(A-2) = 2:1 to 1:2, and more preferably (A-1):(A-2) = 3:2 to 2:3. If the amount of (A-1) is too large, the coating may suffer from poor appearance such as whitening, and sufficient adhesion, durability, and weather resistance may not be obtained. If the amount of (A-2) is too large, the viscosity may become too high, making it difficult to handle, and the coating may have insufficient adhesion, durability, and weather resistance.

[0053] Furthermore, the components (A-1) and (A-2) do not contain structural units to which an organic ultraviolet absorbing group such as a hydroxyphenyltriazine structure, a benzotriazole structure, a benzophenone structure, etc. If such an organic ultraviolet absorbing group bonded to the (co)polymer decomposes, the physical properties such as the glass transition point of the vinyl (co)copolymer to which it is bonded change significantly, resulting in cracking and peeling.

[0054] [Component (B)] The component (B) is an ultraviolet absorber for preventing yellowing and surface deterioration of the substrate, and is one or more compounds selected from the group consisting of (B-1) hydroxyphenyltriazine-based compounds, (B-2) benzophenone-based compounds, and (B-3) benzotriazole-based compounds.

[0055] (1) Component (B-1) Specific examples of the hydroxyphenyltriazine compound (B-1) include 2-[2-hydroxy-4-(1-octyloxycarbonylethoxy)phenyl]-4,6-bis(4-phenylphenyl)-1,3,5-triazine (TINUVIN 479, manufactured by BASF Japan Ltd.), 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-bisbutoxyphenyl)-1,3,5-triazine (TINUVIN 460, manufactured by BASF Japan Ltd.), and Examples of suitable phenols include 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol (TINUVIN 400, BASF Japan Ltd.), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)phenol, Tinuvin 405 (manufactured by BASF), and Tinuvin 477 (manufactured by BASF).

[0056] (2) Component (B-2) Specific examples of the benzophenone-based compound (B-2) include 2,4-dihydroxybenzophenone (Seesorb 106, manufactured by Shipro Chemical Co., Ltd.), 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-n-benzyloxybenzophenone, Examples include 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-diethoxybenzophenone, 2,2'-dihydroxy-4,4'-dipropoxybenzophenone, 2,2'-dihydroxy-4,4'-dibutoxybenzophenone, 2,2'-dihydroxy-4-methoxy-4'-propoxybenzophenone, 2,2'-dihydroxy-4-methoxy-4'-butoxybenzophenone, and 2,3,4-trihydroxybenzophenone.

[0057] (3) Component (B-3) Specific examples of the benzotriazole-based compound (B-3) include 2-(2-hydroxy-5-t-methylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)benzotriazole, 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole (Tinuvin-PS, manufactured by BASF Corporation), and 2-(2-hydroxy-3,5-di-t-butylphenyl)benzotriazole.

[0058] Among these, the following are preferred as component (B): (B-1) 2-[2-hydroxy-4-(1-octyloxycarbonylethoxy)phenyl]-4,6-bis(4-phenylphenyl)-1,3,5-triazine (TINUVIN 479, manufactured by BASF Japan Ltd.), (B-1) 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-bisbutoxyphenyl)-1,3,5-triazine (TINUVIN 460, manufactured by BASF Japan Ltd.); (B-2) 2,4-dihydroxybenzophenone (Seesorb 106, manufactured by Shipro Chemical Co., Ltd.); and (B-3) 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole (Tinuvin-PS, manufactured by BASF Corporation).

[0059] The amount of component (B) blended is 1 to 30 parts by mass, and preferably 10 to 25 parts by mass, per 100 parts by mass of the total of components (A-1) and (A-2). If the amount is less than 1 part by mass, the weather resistance of the coating will be insufficient, and if the amount is more than 30 parts by mass, the adhesion of the coating will decrease and poor appearance of the coating will occur, such as cracking and whitening.

[0060] In particular, it is preferable that the hydroxyphenyltriazine compound (B-1) is contained in an amount of 1 to 5 parts by mass per 100 parts by mass of the total of the (A-1) and (A-2), and it is preferable to use the hydroxyphenyltriazine compound (B-1) in combination with the benzophenone compound (B-2) or the benzotriazole compound (B-3) in order to improve weather resistance.

[0061] [Component (C)] Component (C) is a compound having a cyclic hindered amine structure, and acts as a light stabilizer that captures radicals in the cured film generated by ultraviolet light. Specific examples of compounds having a cyclic hindered amine structure include 3-dodecyl-1-(2,2',6,6'-tetramethyl-4-piperidinyl)pyrrolidine-2,5-dione, N-methyl-3-dodecyl-1-(2,2',6,6'-tetramethyl-4-piperidinyl)pyrrolidine-2,5-dione, N-acetyl-3-dodecyl-1-(2,2',6,6'-tetramethyl-4-piperidinyl)pyrrolidine-2,5-dione, bis(2,2',6,6'-tetramethyl-4-piperidyl)sebacic acid, and sebacine. Acid bis(1,2,2',6,6'-pentamethyl-4-piperidyl), 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, Tinuvin 123 (manufactured by BASF Japan Ltd.), Tinuvin 249 (manufactured by BASF Japan Ltd.), Tinuvin 622-SF (manufactured by BASF Japan Ltd.), Tinuvin 765 (manufactured by BASF Japan Ltd.), condensation product of 1,2,3,4-butanetetracarboxylic acid, 2,2',6,6'-tetramethyl-piperidinol and tridecanol, 8-acetyl-3-dodecyl-7,7',9,9'-tetramethyl-1,3,8-triazaspiro[4,5]decane-2,4-dione, 1,2,3,4-butanetetracarboxylic acid, 1,2,6,6'-pentamethyl-4-piperidinol and β,β,β',β'-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5']undeca a condensation product of 1,2,3,4-butanetetracarboxylic acid, 2,2',6,6'-pentamethyl-4-piperidinol, and β,β,β',β'-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5']undecane)diethanol; and a condensation product of 1,2,3,4-butanetetracarboxylic acid, 2,2',6,6'-pentamethyl-4-piperidinol, and β,β,β',β'-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5']undecane)diethanol. Also, for the purpose of immobilizing a light stabilizer, a silylated cyclic hindered amine compound as described in JP-B-61-56187, for example, 2,2,6,6-tetramethylpiperidino-4-propyltrimethoxysilane, 2,2',6,Examples of suitable light stabilizers include 6'-tetramethylpiperidino-4-propylmethyldimethoxysilane, 2,2',6,6'-tetramethylpiperidino-4-propyltriethoxysilane, 2,2',6,6'-tetramethylpiperidino-4-propylmethyldiethoxysilane, and (partial) hydrolysates thereof. These light stabilizers may be used alone or in combination. Among these, a neutral hindered amine light stabilizer (TINUVIN 249, manufactured by BASF Japan Ltd.) is preferred.

[0062] The blending amount of component (C) is 0.5 to 7 parts by mass, and preferably 1 to 5 parts by mass, per 100 parts by mass of the combined total of components (A-1) and (A-2). If it is less than 0.5 part by mass, weather resistance will be insufficient, and if it exceeds 7 parts by mass, poor appearance such as clouding of the coating will occur.

[0063] [Component (D)] Component (D) is inorganic particles having a median diameter of 100 nm or less as measured by dynamic light scattering. The surfaces of the inorganic particles react with the alkoxysilyl groups contained in the vinyl copolymer (A-1) and / or SiOH groups generated by hydrolysis thereof, thereby improving the strength of the coating. As a result, whitening of the coating, deterioration of adhesion, and cracking can be suppressed over a long period of time. Examples of inorganic particles include particles of metal oxides such as silica, alumina, cerium oxide, zirconium oxide, zinc oxide, and titanium oxide. These particles may be used alone or in combination of two or more. Among these, one or more particles selected from silica, zinc oxide, titanium oxide particles, and composite particles thereof are preferred because they provide good coating appearance and weather resistance, and one or more particles selected from silica and zinc oxide particles are more preferred.

[0064] From the viewpoint of the transparency of the coating, the median diameter of component (D) is preferably 1 to 100 nm, more preferably 3 to 50 nm, and even more preferably 5 to 40 nm. In the present invention, the median diameter of component (D) can be measured by dynamic light scattering using a laser beam, using an apparatus such as Nanotrac UPA-EX150 (manufactured by Nikkiso Co., Ltd.).

[0065] The blending amount of component (D) is 3 to 20 parts by mass, and more preferably 5 to 15 parts by mass, per 100 parts by mass of the combined total of components (A-1) and (A-2). If it is less than 3 parts by mass, weather resistance will be insufficient, and if it exceeds 20 parts by mass, poor appearance such as clouding of the coating will occur.

[0066] [Component (E)] Component (E) is a solvent, and is not particularly limited as long as it dissolves or disperses the above components (A-1), (A-2), (B), (C), and (D). However, a highly polar organic solvent is preferably used as the main solvent. Specific examples of organic solvents include alcohols such as methanol, ethanol, isopropyl alcohol, n-butanol, isobutanol, t-butanol, cyclohexanol, and diacetone alcohol; ketones such as methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, cyclohexanone, and diacetone alcohol; ethers such as dipropyl ether, dibutyl ether, anisole, dioxane, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate; and esters such as ethyl acetate, propyl acetate, butyl acetate, and cyclohexyl acetate. Mixtures of one or more of these solvents can be used. Among these, ethers are preferred, and propylene glycol monomethyl ether is more preferred.

[0067] The amount of component (E) blended is such that the solids concentration of the primer composition of the present invention is 1 to 50% by mass, preferably 5 to 30% by mass. If the concentration is less than this range, the coating is likely to suffer from sagging, twisting, and mottling, while if the concentration is greater than this range, the coating is likely to suffer from blushing, whitening, and cracking.

[0068] [Component (F)] The primer composition of the present invention may absorb water during storage or use, resulting in hydrolysis and condensation of the alkoxysilyl groups in component (A-1), resulting in a decrease in storage stability. To prevent this, a dehydrating agent (F) may be added. Examples of dehydrating agents that can be used include orthocarboxylic acid esters such as methyl orthoformate, ethyl orthoformate, and ethyl orthoacetate; dialkylcarbodiimides such as dicyclohexylcarbodiimide; and solid adsorbents such as silica gel and molecular sieves.

[0069] [Other Components] If necessary, the primer composition of the present invention may contain the dispersant (D) as component within a range that does not adversely affect the effects of the present invention. Examples of dispersants include cationic surfactants, anionic surfactants, nonionic surfactants, and various siloxane compounds reactive with particle surfaces, such as silane coupling agents. Furthermore, if necessary, the primer composition of the present invention may contain pH adjusters, leveling agents, thickeners, pigments, dyes, metal powders, antioxidants, heat reflective / absorbent agents, flexibility agents, antistatic agents, antifouling agents, water repellency agents, and the like, within a range that does not adversely affect the effects of the present invention.

[0070] The primer composition of the present invention can be obtained by mixing the above-mentioned components in the prescribed amounts in accordance with a conventional method.

[0071] <Coated Article> The coated article of the present invention has a substrate and a primer layer comprising a cured coating of a primer composition formed on at least one surface of the substrate directly or via one or more other layers.

[0072] [Substrate] The substrate is not particularly limited, and examples thereof include various plastic materials (organic resin substrates), plastic molded bodies, wood-based products, ceramics, glass, metals, and composites thereof. Among these, various plastic materials (organic resin substrates) are preferably used, and particularly preferred are polycarbonate resins, polystyrene resins, acrylic resins, modified acrylic resins, urethane resins, thiourethane resins, polycondensates of halogenated bisphenol A and ethylene glycol, acrylic urethane resins, halogenated aryl group-containing acrylic resins, and sulfur-containing resins. Furthermore, examples of the resin substrates whose surfaces have been treated include those that have been subjected to chemical conversion treatment, corona discharge treatment, plasma treatment, and treatment with an acid or alkali solution. Furthermore, laminates whose surface layer is formed of a resin different from that of the substrate body can also be used. Specific examples of laminates include laminates produced by co-extrusion or lamination in which an acrylic resin layer or urethane resin layer is present on the surface of a polycarbonate resin substrate, and laminates in which an acrylic resin layer is present on the surface of a polyester resin substrate.

[0073] When a primer layer is formed on the surface of the substrate via another layer, the other layer may include an ultraviolet absorbing layer, a printing layer, a recording layer, a heat ray shielding layer, an adhesive layer, an inorganic vapor deposition film layer, etc.

[0074] [Primer Layer] The primer layer can be obtained by applying the primer composition obtained as described above to at least one surface of a substrate directly or via at least one other layer, and then curing the applied composition.

[0075] Examples of methods for applying the primer composition include various application methods such as brush coating, spraying, dipping, flow coating, roll coating, curtain coating, spin coating, and knife coating.

[0076] The primer composition of the present invention may be cured by leaving it in the air to dry or by heating. The curing temperature and curing time are not particularly limited, but it is preferable to heat it at a temperature equal to or lower than the heat resistance temperature of the substrate for 10 minutes to 2 hours, and more preferably at 80 to 135°C for 30 minutes to 2 hours.

[0077] The thickness of the primer layer is not particularly limited, but is preferably 0.1 to 50 μm. A thickness of 0.1 μm or more is preferable because it improves the ultraviolet shielding ability and suppresses peeling of the coating. Furthermore, a thickness of 50 μm or less is preferable because it improves the crack resistance of the coating. The thickness of the primer layer is more preferably 1 to 20 μm, even more preferably 3 to 15 μm, and most preferably 5 to 12 μm.

[0078] The elastic modulus of the primer layer is preferably 1.5 GPa or more, more preferably 2.0 GPa or more, and even more preferably 4.0 GPa or more. When the elastic modulus is 1.5 GPa or more, the water resistance, heat resistance, durability, and adhesion to the substrate and the silicone hard coat layer described later of the coating film become better. An example of an apparatus for measuring the elastic modulus of such a coating film is a nanoindenter (Heidi Tron Tribo Indenter, manufactured by Bruker Japan Co., Ltd.).

[0079] [Hard Coat Layer] To further impart scratch resistance to the coated article of the present invention, a hard coat layer such as a silicone hard coat layer made of a cured coating of a silicone hard coating composition can be formed on the surface of the primer layer made of a cured coating of the primer composition of the present invention. Such a layered system can impart high scratch resistance and long-term weather resistance at the same time.

[0080] The silicone hard coat layer is not particularly limited as long as it can achieve the above-mentioned effects, but a cured coating of a silicone hard coating composition containing a silicone resin and colloidal silica is preferred. Examples of such coatings include those disclosed in JP-A Nos. 51-2736 and 9-71654.

[0081] Specifically, the silicone hard coating composition preferably contains the following components (A) to (D): (A) a compound represented by the following general formula (6): (R 7 ) m Si(OR 8 ) 4-m (6) (wherein, R 7are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group, and the substituents may be bonded to each other; R 8 each independently represents an alkyl group having 1 to 3 carbon atoms, and m is 0, 1, or 2.) A silicone resin obtained by (co)hydrolyzing and condensing at least one selected from alkoxysilanes represented by the following formula: and their (partial) hydrolyzed condensates; (a) colloidal silica; (c) a curing catalyst; and (d) a solvent.

[0082] (1) Component (A) Component (A) is a silicone resin obtained by (co)hydrolyzing and condensing at least one selected from alkoxysilanes represented by the following general formula (6) and their (partial) hydrolysis and condensation products. (R 7 ) m Si(OR 8 ) 4-m (6)

[0083] In the formula, R 7 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R 7 may be bonded to each other to form a linking group, and R 8 are each independently an alkyl group having 1 to 3 carbon atoms, and m is 0, 1, or 2.

[0084] R 7 The monovalent hydrocarbon group R may be linear, branched, or cyclic, and examples thereof include an alkyl group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, and more preferably 1 to 6 carbon atoms; a cycloalkyl group having 3 to 12 carbon atoms, preferably 3 to 8 carbon atoms, and more preferably 3 to 6 carbon atoms; an alkenyl group having 2 to 12 carbon atoms, preferably 2 to 8 carbon atoms, and more preferably 2 to 6 carbon atoms; and an aryl group having 6 to 12 carbon atoms, preferably 6 to 8 carbon atoms. 7Specific examples of the monovalent hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; alkenyl groups such as vinyl and allyl; and aryl groups such as phenyl. Some or all of the hydrogen atoms in these groups may be substituted with other substituents, specific examples of which include halogen-substituted hydrocarbon groups such as chloromethyl, γ-chloropropyl, and 3,3,3-trifluoropropyl; and (meth)acryloxy-, epoxy-, mercapto-, amino-, and isocyanate-substituted hydrocarbon groups such as γ-(meth)acryloxypropyl, γ-glycidoxypropyl, 3,4-epoxycyclohexylethyl, γ-mercaptopropyl, γ-aminopropyl, and γ-isocyanatopropyl. Another example is an isocyanurate group in which multiple isocyanate-substituted hydrocarbon groups are bonded together. Among these, alkyl groups are preferred when the compound is used in applications requiring scratch resistance and weather resistance, and epoxy, (meth)acryloxy, and isocyanurate-substituted hydrocarbon groups are preferred when toughness and dyeability are required.

[0085] R 8 Examples of the alkyl group having 1 to 3 carbon atoms include methyl, ethyl, n-propyl, and isopropyl groups. Among these, the alkyl group having 1 to 3 carbon atoms is particularly preferred because of its high reactivity in hydrolysis and condensation and the high reactivity of the resulting alcohol R 8 Considering the high vapor pressure of OH and the ease of distillation, a methyl group or an ethyl group is preferred.

[0086] In the above formula (6), when m=0, the general formula: Si(OR 8Specific examples of the tetraalkoxysilane and its partial hydrolysis condensate (A-0) represented by formula (4) include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, partial hydrolysis condensate of tetramethoxysilane (trade name "M Silicate 51", manufactured by Tama Chemicals Co., Ltd., trade name "MSI51", manufactured by Colcoat Co., Ltd., trade name "MS51" and "MS56", manufactured by Mitsubishi Chemical Corporation), partial hydrolysis condensate of tetraethoxysilane (trade name "Silicate 35" and "Silicate 45", manufactured by Tama Chemicals Co., Ltd., trade name "ESI40" and "ESI48", manufactured by Colcoat Co., Ltd.), and partial co-hydrolysis condensate of tetramethoxysilane and tetraethoxysilane (trade name "FR-3", manufactured by Tama Chemicals Co., Ltd., trade name "EMSi48", manufactured by Colcoat Co., Ltd.).

[0087] In the above formula (6), when m=1, the general formula: R 7 Si(OR 8Specific examples of trialkoxysilanes represented by the formula (A-3) and partial hydrolysis condensates thereof (A-1) include hydrogentrimethoxysilane, hydrogentriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltriisopropoxysilane, phenyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-methyltriethoxy ... trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, perfluorooctylethyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-(2-aminoethyl)aminopropyltrimethoxysilane, γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane Examples of suitable silanes include tris(3-trimethoxysilylpropyl)isocyanurate and tris(3-triethoxysilylpropyl)isocyanurate in which isocyanate groups are bonded together, partial hydrolysis condensates of methyltrimethoxysilane (trade names "KC-89S" and "X-40-9220", manufactured by Shin-Etsu Chemical Co., Ltd.), and partial hydrolysis condensates of methyltrimethoxysilane and γ-glycidoxypropyltrimethoxysilane (trade name "X-41-1056", manufactured by Shin-Etsu Chemical Co., Ltd.).

[0088] In the above formula (6), when m=2, the general formula: R 7 2Si(OR 8Specific examples of the dialkoxysilane represented by formula (A-2) and its (partial) hydrolysis condensate (A-2) include methylhydrogendimethoxysilane, methylhydrogendiethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylpropyldimethoxysilane, methylpropyldiethoxysilane, diisopropyldimethoxysilane, phenylmethyldimethoxysilane, vinylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, and N-(2-aminoethyl)aminopropylmethyldimethoxysilane.

[0089] The silicone resin of component (A) may be prepared by using the components (A-0), (A-1), and (A-2) in any desired proportions, but to further improve storage stability, scratch resistance, and crack resistance, it is preferable to use a ratio of 0 to 50% of the number of silicon atoms derived from (A-0), 50 to 100% of the number of silicon atoms derived from (A-1), and 0 to 50% of the number of silicon atoms derived from (A-2) relative to the total number of Si atoms in (A-0), (A-1), and (A-3), and it is even more preferable to use a ratio of 0 to 30% of the number of silicon atoms derived from (A-0), 70 to 100% of the number of silicon atoms derived from (A-1), and 0 to 30% of the number of silicon atoms derived from (A-2). In this case, if the main component (A-1) is 50% or more, the curability is good and the hardness of the cured film is moderate, which is preferable.

[0090] To produce the silicone resin of component (A), components (A-0), (A-1), and (A-2) may be (co)hydrolyzed and condensed by a known method. For example, the silicone resin can be obtained by (co)hydrolyzing and condensing the alkoxysilanes of components (A-0), (A-1), and (A-2) or their (partially) hydrolyzed and condensed products, either alone or in combination, in water having a pH of 1 to 7.5, preferably 2 to 7. In this case, a dispersion of metal oxide fine particles such as silica sol in water may be used. To adjust the pH to this range and promote hydrolysis, inorganic and organic acids such as hydrogen fluoride, hydrochloric acid, nitric acid, formic acid, acetic acid, propionic acid, oxalic acid, citric acid, maleic acid, benzoic acid, malonic acid, glutaric acid, glycolic acid, methanesulfonic acid, and toluenesulfonic acid may be used. Alternatively, a solid acid catalyst such as a cation exchange resin having carboxylic acid or sulfonic acid groups on its surface, or water-dispersed metal oxide fine particles such as acidic water-dispersed silica sol may be used as a catalyst. Furthermore, during the hydrolysis, metal oxide fine particles such as silica sol dispersed in water or an organic solvent may be present.

[0091] In the hydrolysis step, the amount of water used is preferably 20 to 3,000 parts by mass per 100 parts by mass of the total of components (A-0), (A-1), and (A-2). The use of excessive water not only reduces the efficiency of the apparatus, but may also cause a decrease in the coating and drying properties of the final composition due to the influence of the remaining water. Furthermore, in order to improve storage stability, scratch resistance, and crack resistance, the amount of water used is preferably 50 parts by mass or more but less than 150 parts by mass.

[0092] The hydrolysis step may involve dropping or pouring water into the alkoxysilane or its (partial) hydrolysis condensate, or conversely, dropping or pouring the alkoxysilane or its (partial) hydrolysis condensate into water. In this case, the reaction solvent may contain an organic solvent, but it is preferable not to contain an organic solvent. This is because the more organic solvent is contained, the smaller the molecular weight of the resulting silicone resin tends to be.

[0093] The condensation step may be carried out continuously following the hydrolysis step, and is usually carried out at room temperature or under heating at 100°C or less. At temperatures higher than 100°C, gelation may occur. Furthermore, condensation can be promoted by distilling off the alcohol produced by hydrolysis at 80°C or higher under normal or reduced pressure. Furthermore, a condensation catalyst such as a basic compound, an acidic compound, or a metal chelate compound may be added to promote condensation. Before or during the condensation step, an organic solvent may be added to adjust the degree of condensation and the concentration, or a dispersion of metal oxide fine particles such as silica sol in water or an organic solvent may be added. Generally, as the condensation progresses, the silicone resin becomes more highly molecular weight and its solubility in water and the produced alcohol decreases. Therefore, the organic solvent to be added is preferably an organic solvent that dissolves the silicone resin well and has a relatively high polarity and a boiling point of 80°C or higher. Specific examples of such organic solvents include alcohols such as isopropyl alcohol, n-butanol, isobutanol, t-butanol, cyclohexanol, and diacetone alcohol; ketones such as methyl propyl ketone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, cyclohexanone, and diacetone alcohol; ethers such as dipropyl ether, dibutyl ether, anisole, dioxane, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate; and esters such as propyl acetate, butyl acetate, and cyclohexyl acetate.

[0094] The polystyrene-equivalent weight average molecular weight of the obtained silicone resin as determined by GPC analysis is preferably 1,500 to 50,000, and more preferably 2,000 to 20,000. A molecular weight of 1,500 or more provides a coating with excellent toughness and can suppress the occurrence of cracks, while a molecular weight of 50,000 or less can suppress whitening of the coating due to excessively low hardness or phase separation of the resin in the coating.

[0095] (2) Component (A) Component (A) is colloidal silica. The colloidal silica of component (A) is preferably in the form of silica colloidally dispersed in a medium such as water or an organic solvent, and commercially available water-dispersed or organic-dispersed types can be used. Specific examples include Snowtex-O, OS, O40, OL, methanol silica sol, IPA-ST, IBA-ST, PMA-ST, and MEK-ST manufactured by Nissan Chemical Industries, Ltd. From the viewpoint of the transparency and hardness of the resulting hard coat layer, silica having a median diameter of 5 to 50 nm as measured by dynamic light scattering is preferred.

[0096] The amount of colloidal silica blended is preferably 3 to 100 parts by mass, more preferably 6 to 50 parts by mass, and even more preferably 10 to 30 parts by mass, calculated as solid content, per 100 parts by mass of component (a).

[0097] (3) Component (C) Component (C) is a curing catalyst that promotes the condensation reaction of condensable groups, such as silanol groups and alkoxy groups, contained in silicone resin (A). Specific examples of component (C) include lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium methylate, sodium propionate, potassium propionate, sodium acetate, potassium acetate, sodium formate, potassium formate, trimethylbenzylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetramethylammonium acetate, n-hexylamine, tributylamine, diazabicycloundecene (DBU), and dicyandiamide. metal-containing compounds such as tetraisopropyl titanate, tetrabutyl titanate, titanium acetylacetonate, aluminum triisobutoxide, aluminum triisopropoxide, tris(acetylacetonate)aluminum, diisopropoxy(ethylacetoacetate)aluminum, aluminum perchlorate, aluminum chloride, cobalt octylate, cobalt acetylacetonate, iron acetylacetonate, tin acetylacetonate, dibutyltin octylate, and dibutyltin laurate; and acidic compounds such as p-toluenesulfonic acid and trichloroacetic acid. Among these, particularly preferred are sodium propionate, sodium acetate, sodium formate, trimethylbenzylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tris(acetylacetonate)aluminum, and diisopropoxy(ethylacetoacetate)aluminum.

[0098] The amount of component (c) to be added is not particularly limited as long as it is an amount effective for curing the silicone resin of component (a), but specifically, it is preferably 0.0001 to 1 mass % of the solid content of the silicone resin, and more preferably 0.0005 to 0.1 mass %. If it is less than 0.0001 mass %, curing may be insufficient and hardness may decrease, and if it is more than 1 mass %, the coating may be prone to cracking or water resistance may decrease.

[0099] (4) Component (d) Component (d) is a solvent. Examples of solvents for component (d) include those similar to those used as component (E) in the primer composition. The amount of solvent blended is such that the solids concentration of the silicone composition is preferably 5 to 40% by mass, more preferably 10 to 35% by mass.

[0100] (5) Component (E) The silicone hard coating composition may contain an organic UV absorber, such as benzophenone derivatives, benzotriazole derivatives, cyanoacrylate derivatives, or triazine derivatives, as long as the effect of the present invention is not impaired. Specific examples thereof include 2,4-dihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-n-benzyloxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-diethoxybenzophenone, 2,2'-dihydroxy-4,4'-dipropoxybenzophenone, 2,2'-dihydroxy-4,4'-dibutoxybenzophenone, 2,2'-dihydroxy-4-methoxy-4'-propoxybenzophenone, 2,2'-dihydroxy-4-methoxy-4'-butoxybenzophenone, 2,3,4-trihydroxybenzophenone, Benzophenone: 2-(2-hydroxy-5-t-methylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)benzotriazole, Tinuvin-PS (manufactured by BASF), 2-(2-hydroxy-3,5-di-t-butylphenyl)benzotriazole; (2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)phenol, Tinuvin 400 (BASF) Examples of such UV absorbers include Tinuvin 405 (manufactured by BASF), Tinuvin 460 (manufactured by BASF), Tinuvin 477 (manufactured by BASF), Tinuvin 479 (manufactured by BASF), Tinuvin 1577ED (manufactured by BASF), and Tinuvin 1600 (manufactured by BASF). In addition, reactive UV absorbers of the silane coupling agent type in which an alkoxysilyl group is substituted on a portion of the UV absorber can also be used. Among these, reactive UV absorbers of the silane coupling agent type in which an alkoxysilyl group is substituted on a portion of the compound are preferred.By using the reactive ultraviolet absorber, the ultraviolet absorbing group is fixed in the hard coat layer, and bleeding out of the ultraviolet absorber over time is suppressed, which is effective in suppressing whitening and cracking.

[0101] The reactive ultraviolet absorber is preferably a benzophenone derivative having one or more alkoxysilyl groups, represented by the following general formula (7):

[0102]

[0103] In the formula, R 9 are each independently a hydrogen atom, a hydroxy group, an alkyl group having 1 to 5 carbon atoms, or a group represented by the following general formula (8), 9 At least one of the groups is a group represented by the following general formula (8): *—O—(CH2) j -SiR 10 k (OR 11 ) 3-k (8) (wherein, R 10 and R 11 each independently represents an alkyl group having 1 to 5 carbon atoms; j represents an integer of 1 to 8, and k represents an integer of 0 to 2. An asterisk * represents a bond to an adjacent atom.

[0104] In the above formula (7), R 9 The alkyl group in R has 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms, and may be either linear or branched. Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, and isopentyl groups. 9 At least one of the groups R is a group represented by the general formula (8). By having the group represented by the general formula (8), the ultraviolet absorber is fixed in the hard coat layer, and bleeding out over time is suppressed, which is effective in suppressing whitening and cracking of the hard coat layer. 9 At least one of R is preferably a hydroxy group, since this improves ultraviolet absorption. 9 Among these, it is preferable that all of the groups other than the group represented by the general formula (8) and the hydroxy group are hydrogen atoms.

[0105] In the above formula (8), R 10 and R 11 The alkyl group having 1 to 5 carbon atoms is preferably an alkyl group having 1 to 3 carbon atoms, and specific examples thereof include R 9 Among these, R 10 is preferably a methyl group or an ethyl group. 11 is highly reactive in hydrolysis and condensation, and the alcohol R 11 Considering the high vapor pressure of OH and the ease of distillation, a methyl group or an ethyl group is preferred.

[0106] j is an integer of 1 to 8, and from the viewpoint of easy availability of raw materials, an integer of 1 to 3 is preferable, and 3 is more preferable. k is an integer of 0 to 2, and in particular, k=0 is preferable because it increases the reactivity of hydrolysis and condensation and improves the scratch resistance of the coating.

[0107] Among the benzophenone derivatives represented by the above general formula (7), 2-hydroxy-4-trimethoxysilylpropoxybenzophenone is preferred.

[0108] When an organic ultraviolet absorber is added, the amount added is preferably 0.1 to 10 parts by mass, and more preferably 0.2 to 5 parts by mass, per 100 parts by mass of component (a).

[0109] (6) Component (f) Furthermore, inorganic UV absorbers may be added to the silicone hard coating composition as long as the effects of the present invention are not impaired. Inorganic UV absorbers are preferred because they have good compatibility and dispersibility with the coating composition and, when formed into a film, can maintain a certain level of transparency without becoming cloudy. Specific examples include fine particles of single oxides such as titanium oxide, cerium oxide, zinc oxide, tin oxide, zirconium oxide, antimony oxide, tungsten oxide, and iron oxide; composite metal oxide fine particles of the metal elements that make up the above oxides; and mixtures thereof.

[0110] As the inorganic ultraviolet absorber, titanium oxide is preferred in terms of weather resistance and film transparency, and titanium oxide doped with a different metal is more preferred. Elements constituting metal oxides that can be composited with titanium oxide include Group 13 elements, Group 14 elements (excluding carbon), first-series transition elements, second-series transition elements, third-series transition elements, lanthanoids, etc. The different metals may be dispersed or unevenly distributed within the titanium oxide structure. The structure in which the different metals are dispersed within the structure is a structure found in co-hydrolyzates of multiple metal alkoxides. The structure in which the metals are unevenly distributed within the structure is a structure found in core-shell particles (particles having a metal oxide fine particle as a core and a shell of another metal oxide outside the core).

[0111] Titanium oxide is generally classified into three types: rutile, anatase, and brookite. In the present invention, it is preferable to use tetragonal rutile titanium oxide, which has low photocatalytic activity and excellent ultraviolet absorption ability, as a solid solvent for tin and manganese.

[0112] The manganese component as the solid solute may be derived from a manganese salt, and examples thereof include manganese chalcogenides such as manganese oxide and manganese sulfide, with manganese oxide being preferred. Examples of manganese salts include manganese halides such as manganese fluoride, manganese chloride, manganese bromide, and manganese iodide; manganese pseudohalides such as manganese cyanide and manganese isothiocyanide; and manganese mineral acid salts such as manganese nitrate, manganese sulfate, and manganese phosphate, with manganese chloride being preferred due to its stability and availability. Furthermore, the manganese in the manganese salt can be selected from those with a valence of 2 to 7, with divalent manganese being preferred.

[0113] When tin and manganese are dissolved in tetragonal titanium oxide, the amount of the tin component dissolved in the solid solution, in terms of the molar ratio to titanium (Ti / Sn) is preferably 10 to 1,000, more preferably 20 to 200, and the amount of the manganese component dissolved in the solid solution, in terms of the molar ratio to titanium (Ti / Mn) is preferably 10 to 1,000, more preferably 20 to 200. When the amount of the tin component and the manganese component dissolved in the solid solution, in terms of the molar ratio to titanium (Ti / Sn) or (Ti / Mn), is less than 10, the light absorption in the visible region originating from tin and manganese becomes significant; on the other hand, when it exceeds 1,000, the photocatalytic activity is not sufficiently deactivated, and the crystal system may become anatase type, which has low visible light absorption ability.

[0114] The solid solution mode of the tin component and the manganese component may be substitutional or interstitial. Here, substitutional refers to a solid solution mode formed by substitution of tin and manganese at the titanium (IV) ion sites of titanium oxide, while interstitial refers to a solid solution mode formed by the presence of tin and manganese between the crystal lattice of titanium oxide. Interstitial forms are prone to the formation of F centers that cause coloration, and also have poor symmetry around the metal ion, which increases the Franck-Condon factor of the vibronic transition in the metal ion and makes it easier to absorb visible light. Therefore, substitutional forms are preferred.

[0115] As component (f), a core-shell type tetragonal titanium oxide solid solution having a core of tetragonal titanium oxide microparticles containing tin and manganese as a solid solution and a silicon oxide shell surrounding the core is preferred. The silicon oxide shell formed around the core of the tetragonal titanium oxide microparticles containing tin and manganese as a solid solution may be primarily composed of silicon oxide and may contain other components such as tin or aluminum, and may be formed by any method. For example, the silicon oxide shell can be formed by hydrolysis and condensation of a tetraalkoxysilane. Commonly available tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra(n-propoxy)silane, tetra(isopropoxy)silane, and tetra(n-butoxy)silane may be used, but tetraethoxysilane is preferred from the standpoints of reactivity and safety. For example, a commercially available tetraalkoxysilane such as "KBE-04" (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used. Furthermore, the hydrolysis and condensation of tetraalkoxysilane may be carried out in water using a condensation catalyst such as ammonia, aluminum salts, organoaluminum, tin salts, or organotin, as appropriate. Ammonia is particularly preferred because it also acts as a dispersant for the core particles.

[0116] The ratio of silicon oxide in the shell to the total of the core-shell type tetragonal titanium oxide solid solution, which has a core of tetragonal titanium oxide fine particles containing tin and manganese as a solid solution and a silicon oxide shell around the core, is preferably 20 to 50 mass%, more preferably 25 to 45 mass%, and even more preferably 30 to 40 mass%. If it is less than 20 mass%, the formation of the shell may be insufficient, while if it exceeds 50 mass%, the aggregation of the particles may be promoted, resulting in an opaque dispersion.

[0117] In the core-shell type tetragonal titanium oxide solid solution, the volume-based median diameter of the tetragonal titanium oxide fine particles containing tin and manganese as cores, as measured by dynamic light scattering using a laser beam, is preferably 30 nm or less, more preferably 20 nm or less, and the volume-based median diameter of the core-shell type tetragonal titanium oxide solid solution is preferably 50 nm or less, more preferably 30 nm or less. If the median diameters of the core fine particles and the core-shell type solid solution exceed the upper limit values, the dispersion may become opaque. The lower limit of the median diameter of the core fine particles is not particularly limited, but is typically preferably 5 nm or more. The lower limit of the median diameter of the core-shell type solid solution is also not particularly limited, but is typically preferably 6 nm or more. In the present invention, an example of an apparatus for measuring the volume-based median diameter is the Nanotrac UPA-EX150 (manufactured by Nikkiso Co., Ltd.).

[0118] When the inorganic ultraviolet absorber is blended, the blending amount is preferably 0.1 to 30 parts by mass, and more preferably 0.3 to 20 parts by mass, per 100 parts by mass of the total of components (a) and (b).

[0119] (7) Other Components The silicone hard coating composition may contain, as needed, pH adjusters, leveling agents, thickeners, pigments, dyes, metal oxide fine particles, metal powders, antioxidants, ultraviolet absorbers, ultraviolet stabilizers, heat ray reflecting / absorbing agents, flexibility imparting agents, antistatic agents, antifouling agents, water repellency imparting agents, and the like, provided that the effects of the present invention are not impaired.

[0120] The silicone hard coating composition used in the present invention can be obtained by mixing the above-mentioned components in the prescribed amounts in accordance with a conventional method. The obtained silicone composition can be applied to a resin substrate and cured to form a hard coat layer. The silicone hard coating composition can be applied by the same method as that for the primer composition.

[0121] After application, the silicone hard coating composition can be cured by either leaving it to air dry or by heating. There are no particular restrictions on the curing temperature or time, but it is preferable to heat it at a temperature equal to or lower than the heat resistance temperature of the substrate for 10 minutes to 2 hours, and more preferably at 80 to 135°C for 30 minutes to 2 hours.

[0122] The thickness of the obtained silicone hard coat layer is not particularly limited, but is preferably 0.1 to 50 μm. In order to satisfy the requirements of hardness, scratch resistance, long-term stable adhesion, and crack prevention, the thickness is more preferably 1 to 20 μm, even more preferably 3 to 15 μm, and most preferably 5 to 12 μm. A film thickness of 0.1 μm or more is preferred because it improves the ultraviolet shielding ability and suppresses peeling of the film. A film thickness of 50 μm or less is preferred because it improves the crack resistance of the film and suppresses crack occurrence in the film.

[0123] A coated article having excellent transparency, weather resistance, and scratch resistance can be obtained by laminating a hard coat layer obtained by curing the silicone hard coating composition on top of a primer layer obtained by applying the primer composition of the present invention to a substrate.

[0124] The coated article of the present invention having a silicone hard coat layer on a primer layer may further have an ultraviolet absorbing layer, a printing layer, a recording layer, a heat ray shielding layer, an adhesive layer, an inorganic vapor deposition film layer, etc. on the silicone hard coat layer.

[0125] [Physical Properties of Coating] The coated article of the present invention having a silicone hard coat layer on a primer layer has excellent visible light transmittance of the coating. This can be evaluated by the haze value of the coating. Since the haze increases with increasing film thickness, the haze at a film thickness of 20 μm or less is preferably 2.0 or less, more preferably 1.5 or less, and even more preferably 1.0 or less. The haze of the coating can be measured, for example, using a turbidity meter NDH2000 (manufactured by Nippon Denshoku Industries Co., Ltd.).

[0126] The coated article of the present invention having a silicone hard coat layer on a primer layer has excellent adhesion between the coating and the substrate. This can be evaluated as an index by a cross-cut peel test according to JIS K5400. Using a razor blade, 25 cross-cuts were made in the coating at 2 mm intervals, six vertical and six horizontal cuts. Cellotape (registered trademark, manufactured by Nichiban Co., Ltd.) was firmly attached, and the cross-cuts were rapidly peeled off at a 90° angle toward the user. The number of squares (X) remaining without peeling of the coating was expressed as X / 25. The closer the number of squares (X) was to 25, the better the adhesion. Furthermore, a substrate having a cured coating was boiled in water at 100°C for 2 hours, and a similar cross-cut test was then performed, which can be used as an index of water-resistant adhesion.

[0127] The coated article of the present invention having a silicone hard coat layer on a primer layer has excellent scratch resistance. This can be evaluated as an index of the difference in haze (ΔHz) before and after the test in a Taber abrasion test. According to ASTM 1044, a Taber abrasion tester is used to measure the haze after 500 revolutions under a load of 500 gf using a CS-10F abrasion wheel. When the haze is measured using ΔHz (% points) as (haze after test, %) minus (haze before test, %), the ΔHz at a film thickness of 20 μm or less is preferably 10 points or less, more preferably 8 points or less, and even more preferably 6 points or less.

[0128] The coated article of the present invention having a silicone hard coat layer on a primer layer has good weather resistance. As an example of a weather resistance test, an article was subjected to ultraviolet irradiation (irradiation intensity 90 mW / cm) for 4 hours using an Eye Super UV Tester W-151 manufactured by Iwasaki Electric Co., Ltd. 2The weather resistance can be evaluated by observing the condition of the test piece every 120 hours for 10 cycles, each cycle consisting of 12 hours of darkness (black panel temperature 63°C, humidity 70%), 4 hours of darkness (black panel temperature 63°C, humidity 90%), and 4 hours of condensation (black panel temperature 30°C, humidity 95%). Observation methods include visual observation or the use of a microscope. Microscopes that can be used for such purposes are not particularly limited, but examples include laser microscopes (manufactured by Keyence Corporation, device name "VK-8710"). In the weather resistance test, it is preferable that no cracks or peeling occur in the coating even after a 600-hour test, more preferably no cracks or peeling occur in the coating even after an 840-hour test, and even more preferably no cracks or peeling occur in the coating even after a 1080-hour test.

[0129] In the above weather resistance test, one-third of the test time was spent on light irradiation, and the intensity was 900 W / m 2 900W / m 2 The cumulative energy when ultraviolet light of this intensity is irradiated for 1 hour is 0.9 kWh / m 2 However, according to the rules for converting derived units, this is equal to 3.24 MJ (megajoules). Therefore, the cumulative irradiation amount after 1080 hours of the above SUV test is 1080 (test time) × 1 / 3 (light irradiation test rate) × 3.24 (MJ / m 2 ・h)≒1166(MJ / m 2 )

[0130] The test conditions for the weather resistance test in the present invention can be set arbitrarily, but the correlation between the test conditions and outdoor exposure can be easily estimated. For example, when the amount of ultraviolet light outdoors is measured using an ultraviolet illuminance meter (Eye ultraviolet illuminance meter UVP365-1, manufactured by Iwasaki Electric Co., Ltd.), the amount of ultraviolet light is 1×101 W / m 2 (Measured at noon on the vernal equinox on a clear day in Matsuida-cho, Annaka-shi, Gunma Prefecture.) The average annual sunshine hours in Japan are about 2000 hours, so the cumulative annual irradiation in Japan is 2000 (h / year) x 1 (year) x 10 (W / m 2 )=20(kWh / m 2 ) ≒ 72 (MJ / m 2Therefore, the cumulative irradiation amount after 1080 hours of the weather resistance test is equivalent to the cumulative irradiation amount that the sample would receive if used outdoors for approximately 16 years in Japan, using the following formula: 1166 (MJ / m 2 , cumulative irradiation amount after 1080 hours of testing) / 72 (MJ / m 2 The outdoor environment varies depending on latitude and climate, so the test conditions can be changed appropriately depending on the environment in which the cured coating will be used.

[0131] The present invention will be specifically described below with reference to synthesis examples, examples, and comparative examples, but the present invention is not limited to the following examples. In the following examples, % means mass %, parts means parts by mass, and Me means methyl groups. The weight-average molecular weight was measured by gel permeation chromatography (GPC) using standard polystyrene as the reference.

[0132] [1] Synthesis of Copolymer [Synthesis Example 1] <Synthesis of Vinyl Copolymer (A-1-1) Having Alkoxysilyl Groups> A 2-liter flask equipped with a stirrer, condenser, and thermometer was charged with 126 g of isobutyl acetate and 126 g of isopropyl alcohol as solvents and heated to 80°C under a nitrogen stream. A previously prepared monomer mixture solution (a mixture of 50 g of γ-methacryloxypropyltrimethoxysilane, 190 g of methyl methacrylate, 18 g of glycidyl methacrylate, and 1 g of 2,2'-azobis(2-methylbutyronitrile) as a polymerization initiator) was added dropwise to the flask at 80-90°C over 1.5 hours, followed by stirring at 80-90°C for 7 hours. The mixture was then allowed to cool, and finally, 367 g of diacetone alcohol was added to terminate the reaction. The proportion of trimethoxysilyl groups in the resulting vinyl copolymer (A-1-1) having alkoxysilyl groups was 9.4% by mass, and the weight-average molecular weight was 60,800. 5 g of the resulting solution was collected in an aluminum dish and heated in a dryer at 105°C for 1 hour to remove the solvent, and then cooled to 25°C. The resulting solution was in a highly viscous liquid state, and it was determined that the glass transition point of the vinyl copolymer (A-1-1) was 25°C or lower.

[0133] Comparative Synthesis Example 1 Synthesis of Vinyl Copolymer (A'-1-2) Having UV-Absorbing Group and Alkoxysilyl Group A 2-liter flask equipped with a stirrer, a condenser, and a thermometer was charged with 126 g of isobutyl acetate as a solvent and 126 g of isopropyl alcohol, and heated to 80°C under a nitrogen stream. To this was added dropwise a previously prepared monomer mixture solution (a mixture of 90 g of γ-methacryloxypropyltrimethoxysilane, 270 g of methyl methacrylate, 22.5 g of glycidyl methacrylate, 67.5 g of RUVA-1 (2-[2'-hydroxy-5'-(2-methacryloxyethyl)phenyl]-2H-benzotriazole (RUVA-93, manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorbing group, and 1 g of 2,2'-azobis(2-methylbutyronitrile) as a polymerization initiator) at 80 to 90°C over 1.5 hours, followed by stirring at 80 to 90°C for a further 5 hours. The mixture was then allowed to cool, and 367 g of diacetone alcohol was added to terminate the reaction. The obtained vinyl copolymer (A'-1-2) having ultraviolet-absorbing groups and alkoxysilyl groups had a proportion of ultraviolet-absorbing groups of 10.2% by mass, a proportion of trimethoxysilyl groups of 10.2% by mass, and a weight-average molecular weight of 87,800. 5 g of the obtained solution was collected in an aluminum dish and heated in a dryer at 105°C for 1 hour to remove the solvent, and then cooled to 25°C. The resulting solution was in a highly viscous liquid state, and it was determined that the glass transition point of the vinyl copolymer (A'-1-2) was 25°C or lower.

[0134] [2] Synthesis of UV Absorber [Synthesis Example 2] <Synthesis of Organic UV Absorber (X-1)> 4-allyloxy-2-hydroxybenzophenone (25.4 g, 0.1 mol) was suspended in 70 mL of toluene. 0.05 g of platinum catalyst PL50-T (Shin-Etsu Chemical Co., Ltd.) was added, the temperature was raised to 65°C, and trimethoxysilane (29.3 g, 0.24 mol) was added. After stirring at 80°C for 2 hours, the reaction mixture was cooled, and 5 g of Wakogel C-100 (Fujifilm Wako Pure Chemical Industries, Ltd.) was added to adsorb the platinum catalyst, followed by filtration. The solvent was then removed by concentration under reduced pressure, yielding 34.8 g (0.092 mol) of organic UV absorber (X-1) as a red oil. The product 1The H-NMR spectrum was consistent with that of 2-hydroxy-4-trimethoxysilylpropoxybenzophenone.

[0135] [Synthesis Example 3] <Synthesis of inorganic ultraviolet absorber (X-2)> A 10 mass % aqueous dispersion (solid content concentration 10 mass %) of a core-shell type tetragonal titanium oxide solid solution having tetragonal titanium oxide solid solution fine particles containing tin and manganese as a solid solution as a core and a silicon oxide shell around the core was obtained as the inorganic ultraviolet absorber (X-2) by the method described in step (A) of [Synthesis Example 1] of Japanese Patent No. 6269429.

[0136] [3] Preparation of Silicone Hard Coating Composition [Synthesis Example 4] <Preparation of Organic UV Absorber-Containing Silicone Hard Coating Composition (HC-1)> 48 g of methyltrimethoxysilane and 1.2 g of the organic UV absorber (X-1) obtained in Synthesis Example 2 were placed in a 500-milliliter flask equipped with a stirrer, condenser, and thermometer, and the temperature was maintained at 20°C with stirring. 29.4 g of Snowtex O (Nissan Chemical Industries, Ltd., 20% by weight aqueous colloidal silica dispersion, average particle size 15 to 20 nm), 8.2 g of acetic acid, and 30 g of water were added and stirred. After stirring at 60°C for 3 hours, 45 g of n-butanol was added, and a total of 72 g of by-produced methanol and a portion of the water was distilled off under normal pressure. Isopropanol was then added so that the solids concentration was 30% by weight, yielding a solution (Y-1). Next, to 30 g of the solution (Y-1), 0.02 g of polyether-modified silicone KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added as a leveling agent, and 0.2 g of a 10% by mass aqueous solution of tetrabutylammonium hydroxide was added as a curing catalyst, followed by stirring for 1 hour at 25° C. The resulting solution was filtered through filter paper to remove the precipitate, yielding an organic UV absorber-containing silicone hard coating composition (HC-1).

[0137] Synthesis Example 5 Preparation of Inorganic UV Absorber-Containing Silicone Hard Coating Composition (HC-2) 25 g of methyltrimethoxysilane and 7.8 g of the inorganic UV absorber (X-2) obtained in Synthesis Example 3 were placed in a 500-milliliter flask equipped with a stirrer, condenser, and thermometer, and while stirring at 25°C, 21 g of Snowtex O (Nissan Chemical Industries, Ltd., 20% by weight colloidal silica aqueous dispersion, average particle size 15 to 20 nm) and 0.14 g of acetic acid (Wako Pure Chemical Industries, Ltd.) were added, and the mixture was stirred at 60°C for 3 hours. 28 g of cyclohexanone was added, and then a total of 23 g of by-produced methanol and a portion of the water was distilled off under normal pressure. During the distillation, the temperature inside the flask reached 91°C. The resulting suspension was cooled to room temperature, and 4.0 g of acetic acid was added. Furthermore, isopropanol was added so that the solids concentration became 30% by weight, to obtain a solution (Y-2). Next, to 30 g of the solution (Y-2), 0.02 g of polyether-modified silicone KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added as a leveling agent, and 0.2 g of a 10% by mass aqueous solution of tetrabutylammonium hydroxide was added as a curing catalyst, followed by stirring for 1 hour at 25° C. The resulting solution was filtered through filter paper to remove the precipitate, yielding an inorganic UV absorber-containing silicone hard coating composition (HC-2).

[0138] [4] Production of Primer Compositions [Examples 1-1 to 1-14, Comparative Examples 1-1 to 1-13] Primer compositions were obtained by adding propylene glycol monomethyl ether (E-1) to a composition prepared according to a conventional method using the formulations (solids content, parts by mass) shown in Tables 1-1 and 2-1 to adjust the concentration to 5 mass% of the dehydrating agent ethyl orthoformate (F-1) and 500 mass ppm of the leveling agent LE-604 (G-1) in the composition, and to a total solids concentration of 20 mass%. Note that among the abbreviations used in the examples and comparative examples, the abbreviations not explained in the synthesis examples are as follows:

[0139] <Component (A-2)> A-2-1: Polymethyl methacrylate resin (Dianal (registered trademark) BR-88, manufactured by Mitsubishi Rayon Co., Ltd., Mw: 576,900, Tg: 105°C) A-2-2: Polymethyl methacrylate resin (Dianal (registered trademark) BR-85, manufactured by Mitsubishi Rayon Co., Ltd., Mw: 263,800, Tg: 105°C) A-2-3: Polymethyl methacrylate resin (Dianal (registered trademark) LR-1065, 45% methyl ethyl ketone solution manufactured by Mitsubishi Chemical Corporation, Mw: 75,900, Tg: 105°C) A'-2-4: Polymethyl methacrylate resin (Dianal (registered trademark) BR-90, manufactured by Mitsubishi Rayon Co., Ltd., Mw: 258,300, Tg: 65°C)

[0140] <(B) Ultraviolet absorbers> B-1-1: 2-[2-hydroxy-4-(1-octyloxycarbonylethoxy)phenyl]-4,6-bis(4-phenylphenyl)-1,3,5-triazine (TINUVIN 479, manufactured by BASF Japan Ltd.) B-1-2: 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-bisbutoxyphenyl)-1,3,5-triazine (TINUVIN 460, manufactured by BASF Japan Ltd.) B-2-1: 2,4-dihydroxybenzophenone (Seesorb 106, manufactured by Shipro Chemical Co., Ltd.) B-3-1: 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole (Tinuvin-PS, manufactured by BASF Japan Ltd.)

[0141] <(C) Hindered amine light stabilizer> C-1: Neutral hindered amine light stabilizer (TINUVIN 249, manufactured by BASF Japan Ltd.)

[0142] <(D) Inorganic Particles> D-1: Zinc oxide alcohol dispersion (ZNTANB15WT%-E34, solid content concentration 15%, primary particle size 10 to 15 nm, manufactured by CIK Nanotech Co., Ltd.) D-2: Silica propylene glycol monomethyl ether dispersion (PMA-ST, solid content concentration 30%, primary particle size 10 to 15 nm, manufactured by Nissan Chemical Industries, Ltd.)

[0143] <(E) Solvent> E-1: Propylene glycol monomethyl ether

[0144] <(F) Dehydrating Agent> F-1: Ethyl orthoformate

[0145] <(G) Leveling Agent> G-1: LE-604 (manufactured by Kyoeisha Chemical Co., Ltd.)

[0146] [5] Production of coated article and evaluation of physical properties 1 [Examples 2-1 to 2-14, Comparative Examples 2-1 to 2-13] Each of the primer compositions obtained in Examples 1-1 to 1-14 and Comparative Examples 1-1 to 1-13 was applied to a polycarbonate resin plate (thickness 1 mm, product name Iupilon, manufactured by Mitsubishi Plastics, Inc.) with its surface cleaned by a flow coating method to form a cured coating film of approximately 5 to 10 μm, and the resulting film was then heated and cured at 130°C for 90 minutes to form a primer layer.

[0147] (1) Elastic Modulus of Primer Layer: The elastic modulus of the primer layer was determined by nanoindentation using a nanoindenter (Heidi Tron Tribo Indenter, manufactured by Bruker Japan Co., Ltd.). Specifically, the obtained test specimen was cut to 15 mm x 15 mm, and a dedicated sample fixing substrate (10 mm x 10 mm, 1 mm thick) was coated with instant adhesive (Aron Alpha Fast-Acting Multipurpose, manufactured by Toagosei Co., Ltd.). The substrate side of the sample was adhered to the fixing substrate to obtain a measurement sample. The obtained measurement sample was fixed to a dedicated sample fixing table so that the primer layer side was in contact with the indenter. The elastic modulus of the primer layer was determined by analyzing the data obtained when a Berkovich-type indenter was pressed into the surface of the primer layer to a maximum indentation depth of 100 nm at room temperature (23°C) using dedicated software. The elastic modulus was determined by performing the same procedure at three different points on each sample, and the average value was calculated. The results are shown in Tables 1-2 and 2-2.

[0148] [6] Production of Coated Articles and Evaluation of Physical Properties 2 [Examples 3-1 to 3-14, Comparative Examples 3-1 to 3-13] Each of the primer compositions obtained in Examples 1-1 to 1-14 and Comparative Examples 1-1 to 1-13 was applied by dip coating to a surface-cleaned polycarbonate resin plate (5 mm thick, product name: Takiron PC Clear-1600 Type, manufactured by Takiron C.I. Co., Ltd.) to form a cured film of approximately 5 to 10 μm, and then heated and cured at 130°C for 90 minutes to form a primer layer. After the obtained test piece was allowed to cool to room temperature, a silicone composition (HC-1 obtained in Synthesis Example 4 or HC-2 obtained in Synthesis Example 5) described in Tables 1-3 and 2-3 was further applied by dip coating to a cured film of 5 to 10 μm on the primer layer, and then cured at 120°C for 60 minutes to form a silicone hard coat layer. The coated articles thus obtained were used as test pieces, and various physical properties shown in (2) to (7) below were evaluated by the following methods. The results are shown in Tables 1-3 and 2-3.

[0149] (2) Initial Appearance of Coating: The appearance of the test piece was visually observed.

[0150] (3) Transparency: The haze (%) of the test piece was measured using a haze meter (NDH2000, Nippon Denshoku Industries Co., Ltd.).

[0151] (4) Primary Adhesion: In accordance with JIS K5400, a test piece was cut with a razor blade in six lines at 2 mm intervals vertically and horizontally to form 25 grids, and commercially available cellophane adhesive tape was firmly adhered to the grid. The tape was then rapidly peeled off at an angle of 90 degrees toward the user. The number of grids (X) that remained without peeling of the coating was represented as X / 25.

[0152] (5) Water Resistance and Water-Resistant Adhesion: After immersing the test piece in boiling water for 2 hours, an adhesion test was carried out in the same manner as in (4) above.

[0153] (6) Scratch resistance: According to ASTM 1044, a Taber abrasion tester was used with an abrasion wheel CS-10F attached, and the haze was measured after 500 revolutions under a load of 500 gf. The scratch resistance ΔHz (% points) was evaluated by subtracting the haze before the test from the haze after the test.

[0154] (7) Weather resistance: SUV accelerated weather resistance test: Weather resistance was evaluated under the same conditions as those described in WO 2020 / 066993. That is, using an accelerated weather resistance tester Super UV Tester (SUV) manufactured by Iwasaki Electric Co., Ltd., the test piece was subjected to 4 hours of irradiation (irradiation intensity 90 mW / cm 2 , black panel temperature 63°C, humidity 70%), 4 hours of darkness (black panel temperature 63°C, humidity 90%), and 4 hours of condensation (black panel temperature 30°C, humidity 95%) were defined as one cycle, and the presence or absence of coating cracks and coating peeling was confirmed after 1080 hours (90 cycles) and 1320 hours (110 cycles), and the coating appearance after the weather resistance test was evaluated according to the following criteria. [Coating cracks] The coating appearance after the weather resistance test was evaluated according to the following criteria. ⊚: No abnormalities after 1320 hours ○: No abnormalities after 1080 hours, cracks observed throughout the entire coating after 1320 hours ×: cracks observed throughout the entire coating after 1080 hours [Coating peeling] The state of the coating after the weather resistance test was evaluated according to the following criteria. ⊚: No abnormalities after 1320 hours ○: No abnormalities after 1080 hours, peeling observed throughout the entire coating after 1320 hours ×: peeling observed throughout the entire coating after 1080 hours

[0155]

[0156]

[0157]

[0158]

[0159]

[0160] *1) Unable to confirm due to cloudy coating *2) Unable to confirm due to peeling coating

[0161] As shown in Table 1-3, the coated articles of Examples 3-1 to 3-14 exhibited excellent coating transparency and adhesion to the polycarbonate substrate, and also demonstrated excellent weather resistance. On the other hand, as shown in Table 2-3, Comparative Example 3-1, in which the primer composition did not contain component (A-1), Comparative Example 3-4, in which the primer composition did not contain component (B), and Comparative Example 3-6, in which the primer composition did not contain component (C), exhibited coating peeling during the weather resistance test. Comparative Example 3-2, in which the primer composition did not contain component (A-2), Comparative Example 3-3, in which the content of component (A-2) was insufficient, and Comparative Example 3-10, in which a vinyl copolymer with a low glass transition point was used instead of component (A-2), exhibited cloudy coatings and, due to a decrease in the elastic modulus of the primer layer, deteriorated water-resistant adhesion, resulting in coating peeling during the weather resistance test. In Comparative Example 3-5, in which the amount of component (B) contained in the primer composition was excessive, and Comparative Example 3-7, in which the amount of component (C) was excessive, the coating became cloudy and coating cracks occurred in the weather resistance test. In Comparative Example 3-8, in which the primer composition did not contain component (D), coating cracks occurred in the weather resistance test, and in Comparative Example 3-9, in which the blending amount of component (D) was excessive, the coating became cloudy and coating peeling occurred in the weather resistance test. Furthermore, in Comparative Examples 3-11 to 3-13, in which a vinyl copolymer to which an ultraviolet absorber was bonded via a chemical bond was used, coating cracks and coating peeling occurred in the weather resistance test, resulting in poor weather resistance.

Claims

1. A primer composition comprising the following components (A) to (E), in which the mass ratio (A-1):(A-2) of the following component (A-1) to the following component (A-2) is 3:1 to 1:3: (A) The following components (A-1) and (A-2) (A-1) A copolymer containing a structural unit (a) represented by the following formula (1) and a structural unit (b) represented by the following formula (2), and containing no hydroxyphenyltriazine structure, benzophenone structure, or benzotriazole structure. 【Chemistry 1】 [In formula (1), R 1 represents a hydrogen atom, a halogen atom or a methyl group; R 2 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hydroxyl group, an amino group or an epoxy group and which may have an ether bond, a cyano group, an amide group or -X 1 -R 3 (X 1 is an oxygen atom, a carbonyl group, an oxycarbonyl group, or a carbonyloxy group, and R 3 is a hydrogen atom, or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a hydroxyl group, an amino group, or an epoxy group and which may have an ether bond; In formula (2), R 4 represents a hydrogen atom or a methyl group, R 5 and R 6 each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms; X 2 represents a single bond, an arylene group having 6 to 10 carbon atoms, or an alkyleneoxycarbonyl group having 2 to 12 carbon atoms; n represents an integer of 1 to 3; An asterisk * indicates a bond to an adjacent building block.] (A-2) A vinyl (co)polymer having a glass transition point of 80° C. or higher, which does not contain an alkoxysilyl group and does not contain any of a hydroxyphenyltriazine structure, a benzophenone structure, and a benzotriazole structure. : 100 parts by mass of components (A-1) and (A-2) in total (B) One or more ultraviolet absorbents selected from the group consisting of (B-1) hydroxyphenyltriazine-based compounds, (B-2) benzophenone-based compounds, and (B-3) benzotriazole-based compounds: 1 to 30 parts by mass (C) Compound having a cyclic hindered amine structure: 0.5 to 7 parts by mass (D) Inorganic particles having a median diameter of 100 nm or less as measured by dynamic light scattering: 3 to 20 parts by mass (E) Solvent: Amount that gives a solids concentration in the composition of 1 to 50% by mass

2. 2. The primer composition according to claim 1, wherein the structural unit (b) in the component (A-1) is present in an amount of 0.2 to 0.6 mmol / g relative to the total mass of the component (A-1) and the component (A-2).

3. 2. The primer composition according to claim 1, wherein the glass transition point of the component (A-1) is 30° C. or lower.

4. The primer composition according to claim 1, wherein the structural unit (a) in the component (A-1) contains a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4), and the structural unit (b) contains a structural unit represented by the following formula (5): 【Chemistry 2】 (wherein the asterisk * indicates a bond to an adjacent building block.)

5. The primer composition according to claim 1, wherein the component (B) includes the component (B-1), and the blending amount of the component (B-1) is 1 to 5 parts by mass per 100 parts by mass of the total of the component (A-1) and the component (A-2).

6. 2. The primer composition according to claim 1, wherein the component (D) comprises zinc oxide particles.

7. The primer composition according to claim 1 , wherein the component (D) comprises silica particles.

8. 8. A coated article comprising a substrate and a primer layer comprising a cured coating of the primer composition according to claim 1 formed on at least one surface of the substrate directly or via one or more other layers, wherein the primer layer has an elastic modulus of 1.5 GPa or more.

9. 9. The coated article of claim 8, further comprising a silicone hard coat layer on said primer layer.

10. The silicone hard coat layer is (A) The following general formula (6): (R 7 ) m Si(OR 8 ) 4-m (6) (In the formula, R 7 are each independently a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group, 7 may be bonded to each other to form a linking group, 8 are each independently an alkyl group having 1 to 3 carbon atoms, and m is 0, 1, or 2. and (co)hydrolysis and condensation of at least one selected from the group consisting of alkoxysilanes represented by the following formula (1): (a) colloidal silica, (C) a curing catalyst; (D) Solvent The coated article of claim 9 which is a cured coating of a silicone hard coating composition comprising

11. 11. The coated article according to claim 10, wherein the silicone hard coating composition further comprises (e) an organic ultraviolet absorbing agent.

12. 12. The coated article according to claim 11, wherein the component (e) is an organic ultraviolet absorber having an alkoxysilyl group.

13. The coated article according to claim 12, wherein the component (e) is an organic ultraviolet absorber represented by the following general formula (7): 【Chemistry 3】 [In the formula, R 9 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, or a group represented by the following general formula (8), 9 At least one of these is a group represented by the following general formula (8). *-O-(CH 2 ) j -SiR 10 k (OR 11 ) 3-k (8) (In the formula, R 10 and R 11 each independently represents an alkyl group having 1 to 5 carbon atoms; j represents an integer of 1 to 8, and k represents an integer of 0 to 2; and an asterisk * represents a bond to an adjacent atom.

14. 11. The coated article according to claim 10, wherein the silicone hard coating composition further comprises (f) an inorganic ultraviolet absorbing agent.

15. The coated article according to claim 14, wherein the component (f) is a core-shell type tetragonal titanium oxide solid solution having a tetragonal titanium oxide solid solution particle having tin and manganese dissolved therein as a core and a silicon oxide shell around the core, the median diameter of the core-shell type tetragonal titanium oxide solid solution measured by dynamic light scattering is 50 nm or less, the amount of the tin in solid solution is in a molar ratio to titanium (Ti / Sn) of 10 to 1,000, and the amount of the manganese in solid solution is in a molar ratio to titanium (Ti / Mn) of 10 to 1,000.

16. 9. The coated article of claim 8, wherein the substrate is an organic resin substrate.

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