A coating composition for forming a hard coat layer, a method for manufacturing the same, a substrate with a hard coat layer, and a method for manufacturing the same.

Abstract

[Problem] To provide, for example, a coating composition for forming a hard coating layer which makes it possible to, without deteriorating the quality of a hard coating layer to be obtained, reduce the heating time required to cure a coating film and form the hard coating layer. [Solution] A coating composition for forming a hard coating layer comprises: surface-coated inorganic oxide microparticles which are obtained by coating the surfaces of inorganic oxide microparticles with quaternary alkoxysilane; a hydrolysate of an organic silicon compound having an epoxy group and / or a condensate thereof; 1,2,3,4-butanetetracarboxylic acid; and a curing agent, wherein the number average molecular weight of the hydrolysate and / or the condensate thereof is 80-500, and the content of the 1,2,3,4-butanetetracarboxylic acid is 8-25 parts by mass with respect to 100 parts by mass of the surface-coated inorganic oxide microparticles.

Description

[Technical Field]

[0001] The present invention relates to a composition for forming a hard coat layer and a method for manufacturing the same, and more particularly to a composition for forming a hard coat layer typically formed on the surface of a transparent plastic substrate such as an optical lens, a method for manufacturing the same, and a substrate with a hard coat layer and a method for manufacturing the same. [Background technology]

[0002] In recent years, plastic substrates have increasingly replaced inorganic glass substrates as materials for optical lenses, particularly eyeglass lenses. This is because plastic substrates possess superior properties in terms of lightness, impact resistance, processability, and dyeability, and further improvements and development of the material have led to second-generation plastic lenses, resulting in even lighter weight and higher refractive index. However, these plastic substrates have the disadvantage of being more easily scratched than inorganic glass substrates.

[0003] Therefore, to avoid this drawback, the surface of optical lenses made from plastic substrates is usually provided with a silicone-based curable coating, i.e., a hard coat layer. Furthermore, when a high refractive index plastic lens substrate is used, in order to avoid light interference (which appears as interference fringes) between the lens and the hard coat layer, metal oxide fine particles are added to the hard coat layer to match its refractive index to that of the lens substrate.

[0004] For example, Patent Document 1 discloses the use of composite oxide nanoparticles containing titanium oxide, zirconium oxide, and antimony pentoxide as the metal oxide nanoparticles. Patent Document 2 proposes using composite oxide nanoparticles consisting of titanium, silicon, zirconium, and / or aluminum as the metal oxide nanoparticles.

[0005] Patent Document 3 proposes using composite oxide fine particles as the metal oxide particles, which consist of a composite solid solution oxide (core particle) made of a composite oxide of titanium and tin and having a rutile-type structure, with the surface of the composite oxide (coating layer) made of silicon oxide and zirconium and / or aluminum oxide.

[0006] Furthermore, Patent Document 4 proposes the use of metal oxide nanoparticles composed of titanium oxide-containing core particles and a coating layer made of antimony oxide. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 5-264806 [Patent Document 2] Patent No. 3203142 [Patent Document 3] Japanese Patent Publication No. 2000-204301 [Patent Document 4] Japanese Patent Publication No. 2002-363442 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] In conventional technology, the heat treatment required to form a hard coat layer by heat-curing a hard coat coating applied to a substrate takes approximately two hours. It is desirable to shorten this time without compromising the quality of the resulting hard coat layer (for example, its adhesion to the substrate).

[0009] Therefore, the present invention aims to provide a coating composition for forming a hard coat layer that can form a hard coat layer by shortening the heating time required to cure the coating film and form a hard coat layer without impairing the quality of the hard coat layer (for example, adhesion to the substrate, more specifically, at least hardness and adhesion to the substrate), and a method for producing a coating composition for forming a hard coat layer that can shorten the heating time required to cure the coating film and form a hard coat layer without impairing the quality of the resulting hard coat layer (for example, adhesion to the substrate, more specifically, at least hardness and adhesion to the substrate). [Means for solving the problem]

[0010] The present invention relates, for example, to the following [1] to

[12] . [1] Surface-coated inorganic oxide nanoparticles (α0) are obtained by surface-coating inorganic oxide nanoparticles (β0) selected from the group consisting of aluminum oxide-based nanoparticles, silicon oxide-based nanoparticles, titanium oxide-based nanoparticles (β), and zirconium oxide-based nanoparticles with a quaternary alkoxysilane. Hydrolyzates and / or condensates of organosilicon compounds having epoxy groups, 1,2,3,4-butanetetracarboxylic acid, and hardening agent Includes, The number average molecular weight of the hydrolysate and / or its condensate is 80 to 500. The content of 1,2,3,4-butanetetracarboxylic acid is 8 to 25 parts by mass per 100 parts by mass of the surface-coated inorganic oxide fine particles (α0). A coating composition for forming a hard coat layer.

[0011] [2] The hard coat layer forming coating composition of [1], wherein the inorganic oxide fine particles (β0) and the surface-coated inorganic oxide fine particles (α0) are titanium oxide-based fine particles (β) and surface-coated titanium oxide-based fine particles (α), respectively.

[0012] [3] The coating composition for forming a hard coat layer according to [2], wherein the titanium oxide-based fine particles (β) contain 60% by mass or more of Ti in terms of the mass of titanium oxide, and further contain at least one metal element selected from the group consisting of Al, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V.

[0013] [4] The coating composition for forming a hard coat layer according to [2] or [3], wherein the titanium oxide-based fine particles (β) are core-shell type fine particles having titanium oxide-based fine particles as core particles.

[0014] [5] The coating composition for forming a hard coat layer according to any one of [1] to [4], wherein the surface-coated inorganic oxide fine particles (α0) are further surface-modified with the 1,2,3,4-butanetetracarboxylic acid to form modified inorganic oxide fine particles (A0).

[0015] [6] (1) A step of adding 1,2,3,4-butanetetracarboxylic acid to a dispersion of surface-coated inorganic oxide fine particles (α0) in which inorganic oxide fine particles (β0) selected from the group consisting of aluminum oxide-based fine particles, silicon oxide-based fine particles, titanium oxide-based fine particles (β), and zirconium oxide-based fine particles are surface-coated with a quaternary alkoxysilane to obtain a solution A containing further surface-modified modified inorganic oxide fine particles (A0). (2) A step of hydrolyzing an organosilicon compound having an epoxy group at 5 to 15°C to obtain a solution B containing a hydrolyzate, and (3) A step of mixing the solution A, the solution B, a curing agent, and optionally an additive. comprising The addition amount of the 1,2,3,4-butanetetracarboxylic acid is 8 to 25 parts by mass with respect to 100 parts by mass of the surface-coated inorganic oxide fine particles (α). A method for producing a coating composition for forming a hard coat layer.

[0016] [7] A method for producing the hard coat layer forming coating composition of [6], wherein the inorganic oxide fine particles (β0), the surface-coated inorganic oxide fine particles (α0), and the modified inorganic oxide fine particles (A0) are, respectively, the titanium oxide-based fine particles (β), the surface-coated titanium oxide-based fine particles (α), and the modified titanium oxide-based fine particles (A).

[0017] [8] A method for producing the hard coat layer forming coating composition [7], wherein the titanium oxide-based fine particles (β) contain 60% by mass or more of Ti when converted to the mass of titanium oxide, and further contain at least one metal element selected from the group consisting of Al, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V.

[0018] [9] A method for producing the hard coat layer forming coating composition of [7] or [8], wherein the titanium dioxide-based fine particles (β) are core-shell type fine particles with titanium dioxide-based fine particles as core particles.

[0019]

[10] A coating composition for forming a hard coat layer, manufactured by any of the manufacturing methods described in [6] to [9] above.

[0020]

[11] (I) A step of preparing a hard coat layer forming paint composition according to any of the above [1] to [5] and

[10] , or manufacturing a hard coat layer forming paint composition according to any of the above [6] to [9] manufacturing methods, (II) A step of applying the hard coat layer forming paint composition to the surface of a plastic substrate to form a coating film, and (III) A step of heat-curing the coating film. A method for manufacturing a substrate with a hard coat layer containing [the specified component].

[0021]

[12] A substrate with a hard coat layer, comprising a plastic substrate and a hard coat layer formed on the surface of the plastic substrate, wherein the hard coat layer is a thermoset product of any of the hard coat layer forming coating compositions of [1] to [5] and

[10] . [Effects of the Invention]

[0022] According to the coating composition for forming a hard coat layer of the present invention, a hard coat layer can be formed by shortening the heating time required to cure the coating film and form a hard coat layer without impairing the quality of the hard coat layer (for example, adhesion to the substrate, more specifically, at least hardness and adhesion to the substrate).

[0023] The present invention provides a method for producing a hard coat layer-forming composition that can shorten the heating time required to cure the coating film and form a hard coat layer without impairing the quality of the resulting hard coat layer (for example, adhesion to the substrate, more specifically, at least hardness and adhesion to the substrate). [Modes for carrying out the invention]

[0024] The hard coat layer forming composition and the like of the present invention will be described in more detail below. [Composition for forming a hard coat layer] The hard coat layer forming coating composition of the present invention is Surface-coated inorganic oxide fine particles (α0) (for example, surface-coated titanium oxide fine particles (α)) are obtained by surface-coating inorganic oxide fine particles (β0) selected from the group consisting of aluminum oxide fine particles, silicon oxide fine particles, titanium oxide fine particles (β), and zirconium oxide fine particles with a quaternary alkoxysilane. Hydrolyzates and / or condensates of organosilicon compounds having epoxy groups, 1,2,3,4-butanetetracarboxylic acid, Hardener, Optional additives, and any solvent Includes, The number average molecular weight of the hydrolysate and / or its condensate is 80 to 500. The content of 1,2,3,4-butanetetracarboxylic acid is 8 to 25 parts by mass per 100 parts by mass of the surface-coated inorganic oxide fine particles (α0). It is characterized by the following.

[0025] Details of each component will be explained in the following description of "Method for Manufacturing a Hard Coat Layer Forming Coating Composition". [Method for producing a composition for forming a hard coat layer] Furthermore, the method for producing the hard coat layer forming coating composition of the present invention is as follows: (1) A step to obtain a solution A containing modified inorganic oxide fine particles (A0) (for example, modified titanium oxide fine particles (A)) by adding 1,2,3,4-butanetetracarboxylic acid to a dispersion of surface-coated inorganic oxide fine particles (α0) (for example, surface-coated titanium oxide fine particles (α)) which are inorganic oxide fine particles (β0) selected from the group consisting of aluminum oxide fine particles, silicon oxide fine particles, titanium oxide fine particles (β), and zirconium oxide fine particles, which have been surface-coated with a quaternary alkoxysilane. (2) A step of hydrolyzing an organosilicon compound having an epoxy group at 5 to 15°C to obtain a solution B containing a hydrolysate, (3) A step of mixing solution A, solution B, a curing agent, and optionally an additive. Includes, The amount of 1,2,3,4-butanetetracarboxylic acid added is 8 to 25 parts by mass per 100 parts by mass of the surface-coated inorganic oxide fine particles (α0). It is characterized by the following.

[0026] <Process (1)> Step (1) is a step of adding 1,2,3,4-butanetetracarboxylic acid to a dispersion of surface-coated inorganic oxide fine particles (α0) (for example, the surface-coated titanium oxide-based fine particles (α)) to obtain a solution A containing modified inorganic oxide fine particles (A0) (for example, modified titanium oxide-based fine particles (A)). In this invention, the term "solution" does not necessarily mean that all the components in the liquid are dissolved.

[0027] The following describes step (1) in detail, mainly using the case where the inorganic oxide fine particles (β0) are the titanium oxide-based fine particles (β) as an example. (A) Modified titanium oxide-based fine particles: Modified titanium dioxide nanoparticles (A) are obtained by surface-modifying surface-coated titanium dioxide nanoparticles (α) with 1,2,3,4-butanetetracarboxylic acid.

[0028] Furthermore, the surface-coated titanium oxide fine particles (α) are obtained by surface-coating titanium oxide fine particles (β) with a quaternary alkoxysilane. (Titanium dioxide-based microparticles (β)) The titanium oxide-based fine particles (β) typically contain 60% by mass or more of Ti, calculated as titanium oxide (TiO2), and further contain at least one metallic element selected from the group consisting of Al, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V. When the titanium oxide-based fine particles (β) have such a composition, a hard coat layer with a high refractive index can be formed.

[0029] The average particle size of the aforementioned titanium dioxide-based fine particles (β), as measured by dynamic light scattering, is typically 1 to 200 nm. The titanium dioxide-based fine particles (β) may be core-shell type fine particles with titanium dioxide-based fine particles as core particles, for example, core particles mainly composed of titanium dioxide and a shell layer mainly composed of a substance other than titanium dioxide, or they may not have a shell layer.

[0030] Examples of the crystal structure of the core particles include anatase type and rutile type. In the case of the anatase type, the titanium dioxide-based fine particles (β) preferably contain 65% by mass or more of Ti when converted to the mass of titanium dioxide (TiO2). In the case of the rutile type, the titanium dioxide-based fine particles (β) preferably contain 60.0 to 75.0% by mass of Ti, more preferably 60.5 to 65.5% by mass, when converted to the mass of titanium dioxide (TiO2).

[0031] The titanium oxide-based fine particles (β) can be manufactured by conventionally known methods, such as those described in the first line of the right column on page 2 to the 22nd line of the right column on page 3 of Japanese Patent No. 2783417.

[0032] In addition to the titanium oxide-based nanoparticles (β), other examples of the inorganic oxide nanoparticles (β0) include aluminum oxide-based nanoparticles, silicon oxide-based nanoparticles, and zirconium oxide-based nanoparticles.

[0033] The aluminum oxide-based fine particles typically contain 60% by mass or more, preferably 65% ​​by mass or more, of Al, calculated as the mass of aluminum oxide (Al2O3), and may further contain at least one metallic element selected from the group consisting of Ti, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V.

[0034] The silicon dioxide-based fine particles typically contain 60% by mass or more, preferably 65% ​​by mass or more, of Si, calculated as silicon dioxide (SiO2), and may further contain at least one metallic element selected from the group consisting of Al, Ti, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, and V.

[0035] The aforementioned zirconium oxide-based fine particles typically contain 60% by mass or more, preferably 65% ​​by mass or more, of Zr, calculated as the mass of zirconium oxide (ZrO2), and may further contain at least one metallic element selected from the group consisting of Al, Ti, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V.

[0036] (Surface coating treatment of titanium oxide microparticles (α) and titanium oxide microparticles (β) using quaternary alkoxysilanes) The surface-coated titanium dioxide-based fine particles (α) are obtained by surface-coating the surface of the titanium dioxide-based fine particles (β) with a quaternary alkoxysilane. When the surface of the titanium dioxide-based fine particles (β) is coated with a quaternary alkoxysilane, the dispersion state of the modified titanium dioxide-based fine particles (A) in the paint composition produced by the present invention containing the solvent (D) described later is stabilized over a long period of time.

[0037] On the other hand, if a tertiary or lower alkoxysilane is used instead of a quaternary alkoxysilane, the hardness of the hard coat film formed from the resulting paint composition decreases because the tertiary or lower alkoxysilane has fewer reaction sites with the hydrolyzed product (B) of the organosilicon compound having an epoxy group, as described later, compared to the quaternary alkoxysilane.

[0038] As the quaternary alkoxysilane used in the aforementioned surface coating treatment, conventionally known silane coupling agents having hydrolyzable alkoxy groups can be used, and the type can be appropriately selected depending on the type of solvent, etc. These may be used individually or in combination of two or more types.

[0039] Typical examples of quaternary alkoxysilanes include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane. In this surface coating treatment, the quaternary alkoxysilane may be mixed with titanium dioxide-based fine particles (β) and then the alkoxy group of the quaternary alkoxysilane may be hydrolyzed, or the quaternary alkoxysilane may be partially hydrolyzed or hydrolyzed before being mixed with titanium dioxide-based fine particles (β), and then the alkoxy group of the quaternary alkoxysilane may be hydrolyzed as needed.

[0040] Furthermore, at the stage when this surface coating treatment is completed, it is preferable that the alkoxy groups have reacted with the hydroxyl groups present on the surface of the titanium dioxide-based fine particles (β), but it is also acceptable for some of them to remain unreacted. When performing this surface treatment, it is desirable to use titanium dioxide-based fine particles (β) that have hydroxyl groups on their surface.

[0041] To coat the surface of titanium dioxide-based fine particles (β) with a quaternary alkoxysilane, for example, the quaternary alkoxysilane can be mixed with an aqueous alcohol solution in which the titanium dioxide-based fine particles (β) are dispersed, a catalyst can be added as needed, and then the mixture can be left at room temperature for a predetermined time or heat-treated under predetermined temperature conditions.

[0042] Alternatively, the surface of the titanium dioxide-based fine particles (β) may be modified by adding an aqueous alcohol solution containing a partially hydrolyzed and / or hydrolyzed quaternary alkoxysilane to an aqueous alcohol solution containing titanium dioxide-based fine particles (β) and then heating the solution.

[0043] The amount of quaternary alkoxysilane added during the surface coating treatment is preferably 1 to 30 parts by mass, more preferably 2 to 20 parts by mass, per 100 parts by mass of titanium dioxide-based fine particles (β). When the amount added is within this range, the surface coating treatment can be performed while suppressing a decrease in the refractive index of the surface-coated titanium dioxide-based fine particles.

[0044] Examples of commercially available surface-coated titanium oxide-based fine particles (α) include OPTOLAKE 1120Z (8RX-7·A15) (product name, manufactured by JGC Catalysts & Chemicals Co., Ltd., tetraethoxysilane-treated titania sol (methanol dispersion with a solid content of 20% by mass)) and OPTOLAKE F-2 (A-8) (product name, manufactured by JGC Catalysts & Chemicals Co., Ltd., tetraethoxysilane-treated titania sol (methanol dispersion with a solid content of 30% by mass)).

[0045] (Modified titanium dioxide nanoparticles (A) ~ Surface modification treatment of titanium dioxide nanoparticles (α) coated with 1,2,3,4-butanetetracarboxylic acid ~) By reacting the aforementioned surface-coated titanium oxide nanoparticles (α) (i.e., titanium oxide nanoparticles (β) treated with quaternary alkoxysilane) with 1,2,3,4-butanetetracarboxylic acid to form modified titanium oxide nanoparticles (A) in which the unhydrolyzed alkoxy residues of the quaternary alkoxysilane are converted to hydroxyl groups, it appears that in the film-forming process of the composition produced by the method of the present invention, 1,2,3,4-butanetetracarboxylic acid, which also acts as a hydrolysis condensation catalyst for the binder component (organosilicon compound), also acts as a hydrolysis condensation catalyst for the coating formed from the quaternary alkoxysilane. As a result, when the film is subsequently formed, the bonding and integration of the modified titanium oxide nanoparticles (A) and the binder component (organosilicon compound) proceeds strongly, and it was found that a hard coat layer with the same hardness as conventional methods can be obtained even with a shorter thermal curing time when forming the hard coat layer.

[0046] Furthermore, because hardening progresses more easily, it is thought that the time required for the hard coat film to harden can be shortened. The amount of 1,2,3,4-butanetetracarboxylic acid added is 8 to 25 parts by mass, preferably 9 to 23 parts by mass, per 100 parts by mass of the surface-coated titanium oxide-based fine particles (α). If the amount added is above the lower limit, a hard coat layer with excellent scratch resistance and sufficient hardness can be formed. If the amount added is below the upper limit, a hard coat layer with excellent adhesion to the plastic substrate can be formed.

[0047] The modified titanium oxide fine particles (A) are used in an amount of preferably 10 to 70% by mass, more preferably 15 to 60% by mass, based on 100% by mass of the solid content (the hydrolysis groups of the organosilicon compound (B) described later are assumed to be completely condensed) of the composition produced by the method of the present invention.

[0048] If the amount is greater than or equal to the lower limit, a hard coat layer with excellent scratch resistance and a high refractive index can be formed. If the amount is less than or equal to the upper limit, a hard coat layer that is less prone to cracking and has high adhesion to the plastic lens substrate can be formed.

[0049] <Process (2)> Step (2) is a step in which an organosilicon compound (B) having an epoxy group (hereinafter also simply referred to as "organosilicon compound (B)") is hydrolyzed at 5 to 15°C to obtain a solution B containing the hydrolysate.

[0050] (B) Organosilicon compounds having epoxy groups: Examples of organosilicon compounds (B) having an epoxy group include compounds represented by the following formula (I) that have an alkoxy group as a hydrolyzable group.

[0051] R 1 a R 2 b Si(OR 3 ) 4-(a+b)(I) In formula (I), R 1 is an organic group having 8 or less carbon atoms and containing an epoxy group, and R 2 is an alkyl group having 1 to 3 carbon atoms, a cycloalkyl group having 3 carbon atoms, a halogenated alkyl group having 1 to 3 carbon atoms or an allyl group, and R 3 is an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 3 to 4 carbon atoms.

[0052] a is 0 or 1, and b is 0, 1 or 2. Examples of the organosilicon compound having an epoxy group represented by the above formula (I) (hereinafter also referred to as "organosilicon compound (b)") include alkoxysilane compounds as representative examples. Specifically, α-glycidoxy methyltrimethoxysilane, α-glycidoxy ethyltrimethoxysilane, β-glycidoxy ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, β-(3,4-epoxycyclohexyl)-ethyltriethoxysilane and the like can be mentioned. Among these, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane are preferable. These organosilicon compounds (b) may be used alone or in combination of two or more. A part of the alkoxy groups of the organosilicon compound (b) may be hydrolyzed as long as the effects of the present invention are not impaired.

[0053] The organosilicon compound (B) having an epoxy group is preferably used in an amount of 20 to 70% by weight, more preferably 30 to 60% by weight, based on 100% by weight of the solid content of the composition produced by the method of the present invention (assuming that the hydrolyzable groups of the organosilicon compound (B) having an epoxy group are completely condensed).

[0054] If the amount is greater than or equal to the lower limit, a hard coat layer with excellent adhesion to plastic lens substrates and the like can be formed. If the amount is less than or equal to the upper limit, a hard coat layer with excellent scratch resistance and a high refractive index can be formed.

[0055] Hydrolysis: In step (2), hydrolysis is carried out under the following conditions. The organosilicon compound (B) having an epoxy group is diluted with alcohol or the like, and then diluted hydrochloric acid water is added and mixed. Preferably, each of the mixed components is stirred at 20-30°C for 0.5-2 hours, and then stirred at 5-15°C for 24-72 hours. Stirring under these conditions suppresses the condensation of the hydrolysate of the organosilicon compound (B) having an epoxy group.

[0056] The number-average molecular weight (Mn) of the hydrolysis product (including its condensate) of the epoxy group-containing organosilicon compound (B) obtained by step (2), as measured by the method used in the examples described later, is usually 80 to 500, preferably 90 to 450.

[0057] <Process (3)> Step (3) is a step of mixing solution A, solution B, a curing agent, and optionally an additive. By going through step (3), a coating composition for forming a hard coat layer is obtained.

[0058] Details of the aforementioned hardening agent, etc., are as follows. (C) Hardener: Examples of curing agents (C) include at least one selected from the group consisting of polycarboxylic acids and polycarboxylic acid anhydrides (hereinafter also referred to as "polycarboxylic acids"), as well as cyanamide derivative compounds.

[0059] (Polyhydric carboxylic acids) Examples of polycarboxylic acids include organic carboxylic acids such as adipic acid, itaconic acid, malic acid, 1,2,3,4-butanetetracarboxylic acid, trimellitic anhydride, pyromelitic anhydride, and hexahydrophthalic anhydride; Acetylacetone iron(III), etc., general formula: M(CH2COCH2COCH3) n Acetylacetone metal chelate compounds represented by (where M is a metallic element and n is the valence of metallic element M); Metal alkoxides such as titanium alkoxide and zircoalkoxide; Alkali metal organic carboxylates such as sodium acetate and potassium acetate; Perchlorates such as lithium perchlorate and magnesium chlorate These are some examples.

[0060] Among these, organic carboxylic acids and general formula: M(CH2COCH2COCH3) are considered to have good adhesion between the hard coat layer and the plastic substrate. n Acetylacetone metal chelate compounds represented by are preferred, with adipic acid, itaconic acid, and iron(III) acetylacetone being particularly preferred. These may be used individually or in combination of two or more.

[0061] (Cyanamide derivative compound) Examples include guanidine, guanidine organic acids, guanidine inorganic salts, alkylguanidines, aminoguanidines, and dicyandiamides. Examples of guanidine organic acids include guanidine acetate and guanidine propionic acid, examples of guanidine inorganic salts include guanidine hydrochloride, guanidine nitrate, and guanidine phosphate, and examples of alkylguanidines include n-dodecylguanidine. Among these, guanidine organic acids, guanidine inorganic salts, and dicyandiamides are preferred.

[0062] The component derived from the polycarboxylic acids is used in an amount of preferably 0.5 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the organosilicon compound (B).

[0063] If the aforementioned amount is greater than or equal to the lower limit, a hard coat layer with sufficient hardness can be formed. Furthermore, if the aforementioned amount is less than or equal to the upper limit, the storage stability of the composition produced by the present invention is good.

[0064] The component derived from the curing agent (C) is used in an amount of preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass, per 100 parts by mass of the organosilicon compound (B). The total amount of polycarboxylic acids and cyanamide derivative compounds does not exceed the amount of polycarboxylic acids mentioned above.

[0065] (D) Solvent: Solvent (D) is a liquid used to dissolve or disperse each of the above-mentioned components and any additives described later. The composition produced by the present invention has high fluidity due to the inclusion of solvent (D), making it easy to apply to a substrate.

[0066] Examples of solvent (D) include water such as distilled water or pure water; alcohols such as methanol, ethanol, and propanol; ketones such as methyl ethyl ketone and diacetone alcohol; esters such as ethyl acetate and butyl acetate; and cellosolves such as ethyl cellosolve and butyl cellosolve. Among these, lower alcohols such as methanol and water are preferred. These solvents may be used individually or in mixtures of two or more.

[0067] The solvent (D) is used in an amount that is preferably 50 to 90% by mass, and more preferably 60 to 80% by mass, based on 100% by mass of the composition produced by the present invention. Optional additives: Examples of the aforementioned optional additives include leveling agents, ultraviolet absorbers, and light stabilizers.

[0068] Examples of leveling agents include surfactants, more specifically, silicone-based surfactants such as polyoxyalkylene dimethylpolysiloxane and fluorine-based surfactants such as perfluoroalkyl carboxylates and perfluoroalkyl ethylene oxide adducts. Among these, silicone-based surfactants are preferred.

[0069] Examples of UV absorbers include benzophenone-based UV absorbers and benzotriazole-based UV absorbers. Examples of the aforementioned light stabilizers include hindered amine-based light stabilizers.

[0070] Mixing of each component: The mixing of each component is preferably carried out at 5 to 20°C, more preferably at 10 to 15°C. In step (3), preferably, solution A and solution B are first mixed, and then the curing agent and any additives are mixed in. When mixing solution A and solution B, preferably, solution A is mixed into solution B in small amounts.

[0071] The mixed components are preferably stirred at 20-30°C for 0.5-2 hours, and then stirred at 5-15°C for 24-72 hours. Stirring under these conditions suppresses the reaction of each mixture.

[0072] [Method for manufacturing a substrate with a hard coat layer] The method for producing a substrate with a hard coat layer according to the present invention is: (I) A step of manufacturing a coating composition for forming a hard coat layer by the manufacturing method described above, (II) A step of applying the hard coat layer forming paint composition obtained in step (I) to a plastic substrate (i.e., the surface of the plastic substrate) to form a coating film. (III) A step of heating and curing the coating film. It is characterized by containing [something].

[0073] Step (I) may be replaced with the step of preparing the hard coat layer forming coating composition of the present invention described above. In step (II), known methods such as dipping or spin coating can be used to apply the hard coat layer forming coating composition onto the plastic substrate. Examples of the plastic substrate include plastic substrates made of polycarbonate resin, polyamide resin, PMMA resin, allyl resin, polythiourethane resin, polythioepoxy resin, and the like.

[0074] In step (III), a hard coat layer is formed on the plastic substrate by thermal curing the coating film formed in step (II). According to the present invention, this thermal curing (main curing) can be carried out under the following conditions.

[0075] Temperature: Preferably 80-130°C, more preferably 100-120°C Time: Preferably 20-60 minutes, more preferably 20-40 minutes In thermal curing, pre-curing may be performed at a temperature of 80-100°C for 10-15 minutes, followed by main curing under the same conditions but at a higher temperature than the pre-curing. Performing thermal curing in this stepwise manner mitigates the rapid curing shrinkage of the coating film, suppressing cracking of the coating film and deformation of the plastic substrate.

[0076] By using the hard coat layer forming paint composition of the present invention, or a hard coat layer forming paint composition manufactured by the manufacturing method of the present invention, the time required for thermal curing can be shortened compared to the conventional technology, and the heating temperature can be lowered without impairing the quality of the resulting hard coat layer (e.g., adhesion to the substrate), thereby improving the productivity of hard coat layer formation.

[0077] The thickness of the cured coating, i.e., the hard coat layer, is preferably 1.0 to 5.0 μm, and more preferably 1.5 to 3.5 μm. In this way, a hard coat layer with a refractive index of 1.52 or higher, more specifically in the range of 1.57 to 1.75, can be formed.

[0078] In the aforementioned substrate with a hard coat layer, depending on its intended use, an anti-reflective film may be formed on the surface of the hard coat layer opposite to the plastic substrate, and a primer layer may be formed between the plastic lens substrate and the hard coat layer. Conventionally known materials can be used as the anti-reflective film and primer layer. [Examples]

[0079] The present invention will be described in detail below with reference to examples, but the present invention is not limited in any way to these examples. [Method for measuring the number-average molecular weight of hydrolysates of silane compounds and their condensates] In the examples, the number-average molecular weight of the hydrolysates of silane compounds and their condensates was measured by the following method.

[0080] A sample with a solid content of 3.0% by mass was prepared by mixing a solution containing hydrolysates with tetrahydrofuran (manufactured by Kanto Chemical Co., Ltd.). 0.1 ml of this sample was taken using a microsyringe and subjected to a column (TSK-GEL G3000HLL and TSK-GEL G2500HXL, manufactured by Tosoh Corporation). The number-average molecular weight (Mn) of the solid content in the solution (hydrolysates and / or condensates of silane compounds) in polystyrene equivalent was measured using gel permeation chromatography (HLC-8120GPC, manufactured by Tosoh Corporation).

[0081] [Raw materials] The following raw materials were used in the examples and comparative examples. • γ-Glycidoxypropyltrimethoxysilane: SILQUEST A-187J (product name, manufactured by Momentive) • Silicone-based surfactant: DOWSIL L-7001 (product name, manufactured by Dow Chemical) • Tetraethoxysilane-treated titania sol (methanol dispersion with a solid content of 20% by mass): OPTOLAKE 1120Z (8RX-7·A15) (product name, manufactured by JGC Catalysts & Chemicals Co., Ltd.) • γ-Glycidoxypropyltrimethoxysilane-treated titania sol (methanol dispersion with a solid content of 20% by mass): OPTOLAKE 1120Z (8RX-25·G) (product name, manufactured by JGC Catalysts & Chemicals Co., Ltd.)

[0082] [Example 1] (Manufacturing of paint compositions) 334 g of tetraethoxysilane-treated titania sol was added to 7 g of 1,2,3,4-butanetetracarboxylic acid at room temperature (20-30°C, the same applies below). This solution was stirred at room temperature overnight to obtain titania sol preparation (A1).

[0083] 83 g of γ-glycidoxypropyltrimethoxysilane was mixed with 12 g of methanol while stirring, and then 24 g of 0.01 N aqueous hydrochloric acid solution was added dropwise. The resulting solution was stirred at room temperature for 1 hour, and then stirred at 10°C for 48 hours to hydrolyze the silane compound, yielding a solution (B1) containing the hydrolysate of the silane compound. A solution for measuring the number-average molecular weight of the hydrolysate and / or condensate of the silane compound was prepared by the same method. The number-average molecular weight was in the range of 80 to 500.

[0084] While stirring solution (B1) at 10°C, the entire amount of titania sol preparation solution (A1) was added to solution (B1) in small amounts. Then, 25 g of propylene glycol monomethyl ether, 5 g of dicyandiamide, and 1 g of silicone-based surfactant as a leveling agent were added. The resulting solution was stirred at room temperature for 1 hour, and then stirred at 10°C for 48 hours to obtain a coating composition (P1) for forming a hard coat layer.

[0085] (Manufacturing of substrates with hard coat layer) A CR-39 (allyl diglycol carbonate) lens (product name: 150UC, manufactured by Shanghai Conant Optics Co., Ltd.) was etched by immersing it in an 8% NaOH aqueous solution for 10 minutes.

[0086] A hard coat layer-forming coating composition (P1) was applied to the etched lens surface by dipping (pulling speed: 230 mm / min). The lens coated with the paint composition was heated at 100°C for 10 minutes to pre-cur the coating, and then heated at 120°C for 30 minutes to perform the final curing, thereby obtaining a substrate (H1a) with a hard coat layer.

[0087] Furthermore, the substrate was changed to a thiourethane lens (product name: MR-7, manufactured by Mitsui Chemicals, Inc., refractive index 1.67), and the same procedure as described above was performed to obtain a substrate with a hard coat layer (H1b). [Example 1a] A substrate with a hard coat layer was obtained in the same manner as in Example 1, except that the heating temperature was changed to 100°C during the curing process.

[0088] [Example 1b] A substrate with a hard coat layer was obtained in the same manner as in Example 1, except that the heating temperature was changed to 110°C during the curing process.

[0089] [Example 2] (Manufacturing of paint compositions) A coating composition for forming a hard coat layer (P2) was obtained in the same manner as in Example 1, except that the amount of 1,2,3,4-butanetetracarboxylic acid added was changed to 14 g.

[0090] (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (P2).

[0091] [Example 2a] A substrate with a hard coat layer was obtained in the same manner as in Example 2, except that the heating temperature was changed to 100°C during the curing process.

[0092] [Example 2b] A substrate with a hard coat layer was obtained in the same manner as in Example 2, except that the heating temperature was changed to 110°C during the curing process.

[0093] [Comparative Example 1] (Manufacturing of paint compositions) 83 g of γ-glycidoxypropyltrimethoxysilane was mixed with 12 g of methanol while stirring, and then 24 g of 0.01 N aqueous hydrochloric acid solution was added dropwise. The resulting solution was stirred at room temperature overnight to obtain a solution (b1) containing the hydrolysate of the silane compound. Solutions for measuring the number-average molecular weight of the hydrolysate and condensate of the silane compound were prepared by the same method. The number-average molecular weight was outside the range of 80 to 500.

[0094] Next, 334 g of tetraethoxysilane-treated titania sol, 25 g of propylene glycol monomethyl ether, 66 g of methanol, 7 g of itaconic acid, 5 g of dicyandiamide, and 1 g of a silicone-based surfactant as a leveling agent were added to solution (b1). The resulting solution was stirred at room temperature overnight to obtain a coating composition for hard coat film formation (p1).

[0095] (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (p1).

[0096] [Reference example 1] A substrate with a hard coat layer was obtained in the same manner as in Comparative Example 1, except that the heating time was changed to 120 minutes during the curing process.

[0097] [Comparative Example 2] (Manufacturing of paint compositions) A coating composition for forming a hard coat film (p2) was obtained in the same manner as in Comparative Example 1, except that 7 g of itaconic acid was replaced with 7 g of 1,2,3,4-butanetetracarboxylic acid.

[0098] (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (p2).

[0099] [Comparative Example 3] (Manufacturing of paint compositions) A coating composition for forming a hard coat layer (p3) was obtained in the same manner as in Example 1, except that the amount of 1,2,3,4-butanetetracarboxylic acid added was changed to 5 g.

[0100] (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (p3).

[0101] [Comparative Example 4] (Manufacturing of paint compositions) A coating composition for forming a hard coat layer (p4) was obtained in the same manner as in Example 1, except that the amount of 1,2,3,4-butanetetracarboxylic acid added was changed to 18 g.

[0102] (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (p4).

[0103] [Comparative Example 5] (Manufacturing of paint compositions) 83 g of γ-glycidoxypropyltrimethoxysilane was mixed with 12 g of methanol while stirring, and then 24 g of 0.01 N aqueous hydrochloric acid was added dropwise. The resulting solution was stirred at room temperature overnight to hydrolyze the silane compound, and a solution (b5) containing the hydrolysate of the silane compound was obtained. Solutions for measuring the number-average molecular weight of the hydrolysate and condensate of the silane compound were prepared by the same method. The number-average molecular weight was outside the range of 80 to 500.

[0104] A coating composition (p5) for forming a hard coat layer was obtained in the same manner as in Example 1, except that solution (B1) was changed to solution (b5). (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (p5).

[0105] [Comparative Example 6] (Manufacturing of paint compositions) A coating composition for forming a hard coat layer (p6) was obtained in the same manner as in Example 1, except that 334 g of tetraethoxysilane-treated titania sol was replaced with 334 g of γ-glycidoxypropyltrimethoxysilane-treated titania sol.

[0106] (Manufacturing of substrates with hard coat layer) Two types of substrates with hard coat layers were obtained in the same manner as in Example 1, except that the coating composition for forming the hard coat layer (P1) was changed to the coating composition for forming the hard coat layer (p6).

[0107] <Evaluation of substrates with hard coat layer> The hard-coat coated substrates produced in each example and comparative example were tested or evaluated using the following methods. The evaluation results are shown in Tables 1 and 2.

[0108] [Staining Test] When a substrate with a hard coat layer is immersed in a dyeing solution, the dye passes through the hard coat layer and the substrate is dyed. If the hard coat layer is well-hardened, less dye passes through the hard coat layer, and the substrate is not dyed. On the other hand, if the hard coat layer is not sufficiently hardened, more dye passes through the hard coat layer, and the substrate is dyed.

[0109] For substrates with a hard coat layer manufactured using CR-39 lenses, the luminous transmittance (%) of the dyed lenses was measured using a luminous transmittance meter. Dyeability test conditions 1) Dye name: Optisafe Gray #C250-10 (manufactured by Phantom Research Laboratories inc.) Dye concentration: 2.6% by weight Dispersion medium: Purified water 2) Staining conditions: 92°C × 10 minutes 3) Luminous transmittance meter: Luminous transmittance checker TLV-304 (manufactured by Asahi Spectroscopic Co., Ltd.)

[0110] [Other reviews] The following evaluations were performed on substrates with a hard coat layer manufactured using thiourethane lenses.

[0111] (1) Appearance (clouding of the paint film) The haze value (%) was measured using a haze meter (NDH5000, manufactured by Nippon Denshoku). (2) Appearance (cracks) The cracks were visually confirmed under a three-wavelength desk fluorescent lamp.

[0112] Judgment criteria Good: No cracks. Defect: Cracked (3) Scratch resistance test Using Bonstar steel wool #0000, the surface of the hardened coating (hard coat layer) was rubbed 30 times with a load of 700g, and the number of scratches on the hardened coating was visually confirmed.

[0113] (4) Adhesion test Using a utility knife, 11 vertical and 11 horizontal cuts reaching the lens were made on the surface of the hardened coating (hard coat layer), creating a grid of 100 squares.

[0114] Cellophane tape was firmly pressed onto the grid lines and then quickly peeled off at a 90-degree angle. This operation was repeated a total of 10 times, and the number of squares that were peeled off was counted.

[0115] [Table 1]

[0116] [Table 2]

Claims

1. Inorganic oxide nanoparticles (β) selected from the group consisting of aluminum oxide nanoparticles, silicon oxide nanoparticles, titanium oxide nanoparticles (β), and zirconium oxide nanoparticles. 0 Surface-coated inorganic oxide fine particles (α) are surface-coated with a quaternary alkoxysilane. 0 ), Hydrolyzates and / or condensates of organosilicon compounds having epoxy groups, 1,2,3,4-butanetetracarboxylic acid, and hardening agent Includes, The number average molecular weight of the hydrolysate and / or its condensate is 80 to 500. The content of the 1,2,3,4-butanetetracarboxylic acid is such that the surface-coated inorganic oxide fine particles (α 0 ) 8 to 25 parts by mass per 100 parts by mass, A coating composition for forming a hard coat layer.

2. The inorganic oxide fine particles (β 0 ) and the surface-coated inorganic oxide fine particles (α 0 The coating composition for forming a hard coat layer according to claim 1, wherein the above are the titanium oxide-based fine particles (β) and the surface-coating titanium oxide-based fine particles (α), respectively.

3. The hard coat layer forming paint composition according to claim 2, wherein the titanium oxide-based fine particles (β) contain 60% by mass or more of Ti when converted to the mass of titanium oxide, and further contain at least one metal element selected from the group consisting of Al, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V.

4. The coating composition for forming a hard coat layer according to claim 2, wherein the titanium dioxide-based fine particles (β) are core-shell type fine particles with titanium dioxide-based fine particles as core particles.

5. The coating composition for forming a hard coat layer according to claim 3, wherein the titanium dioxide-based fine particles (β) are core-shell type fine particles with titanium dioxide-based fine particles as core particles.

6. (1) Inorganic oxide fine particles (β) selected from the group consisting of aluminum oxide fine particles, silicon oxide fine particles, titanium oxide fine particles (β), and zirconium oxide fine particles. 0 Surface-coated inorganic oxide fine particles (α) are surface-coated with a quaternary alkoxysilane. 0 ) is mixed with 1,2,3,4-butanetetracarboxylic acid to further modify surface-modified inorganic oxide fine particles (A 0 A step to obtain solution A containing ) (2) A step of hydrolyzing an organosilicon compound having an epoxy group at 5 to 15°C to obtain a solution B containing a hydrolysate, (3) A step of mixing solution A, solution B, a curing agent, and optionally an additive. Includes, The addition amount of the 1,2,3,4-butanetetracarboxylic acid is 8 to 25 parts by mass with respect to 100 parts by mass of the surface-coated inorganic oxide fine particles (α 0 ). A method for producing a coating composition for forming a hard coat layer.

7. The inorganic oxide fine particles (β 0 ), the surface-coated inorganic oxide fine particles (α 0 ) and the modified inorganic oxide fine particles (A 0 A method for producing a coating composition for forming a hard coat layer according to claim 6, wherein the elements are, respectively, the titanium oxide-based fine particles (β), the surface-coated titanium oxide-based fine particles (α), and the modified titanium oxide-based fine particles (A).

8. A method for producing a coating composition for forming a hard coat layer according to claim 7, wherein the titanium oxide-based fine particles (β) contain 60% by mass or more of Ti when converted to the mass of titanium oxide, and further contain at least one metal element selected from the group consisting of Al, Zr, Sb, Zn, Ni, Fe, Ba, Mg, Sn, Si, and V.

9. The method for producing a coating composition for forming a hard coat layer according to claim 7, wherein the titanium dioxide-based fine particles (β) are core-shell type fine particles having titanium dioxide-based fine particles as core particles.

10. The method for producing a coating composition for forming a hard coat layer according to claim 8, wherein the titanium dioxide-based fine particles (β) are core-shell type fine particles having titanium dioxide-based fine particles as core particles.

11. (I) A step of preparing a coating composition for forming a hard coat layer according to any one of claims 1 to 5, (II) A step of applying the hard coat layer forming paint composition to the surface of a plastic substrate to form a coating film, and (III) A step of heat-curing the coating film. A method for manufacturing a substrate with a hard coat layer containing [the specified component].

12. (I) A step of manufacturing a coating composition for forming a hard coat layer by a manufacturing method described in any one of claims 6 to 10, (II) A step of applying the hard coat layer forming paint composition to the surface of a plastic substrate to form a coating film, and (III) A step of heat-curing the coating film. A method for manufacturing a substrate with a hard coat layer containing [the specified component].

13. A substrate with a hard coat layer, comprising a plastic substrate and a hard coat layer formed on the surface of the plastic substrate, wherein the hard coat layer is a thermoset product of the hard coat layer forming coating composition according to any one of claims 1 to 5.

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