Liniment for forming antifogging film, production method of antifogging article, and antifogging article

Abstract

To provide: a liniment for forming antifogging film capable of forming an antifogging film which is excellent in antifogging property and anti-fouling property with one liquid; a production method of an antifogging article using the liniment for forming antifogging film; and the antifogging article.SOLUTION: Provided are: a liniment for forming antifogging film including (A) a polyisocyanate having two or more isocyanate groups, (B) a polyol including an oxy-ethylene unit as a repeating unit and having two or more hydroxy groups in a molecule, (C) a first water repellent which is a silicone-based acrylic polymer having two or more hydroxy groups in a molecule, and (E) a solvent; a production method of an antifogging article using the liniment for forming antifogging film; and the antifogging article.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to a coating agent for forming an anti-fogging film, a method for producing an anti-fogging article, and an anti-fogging article. [Background technology]

[0002] To ensure visibility of transparent substrates such as bathroom and vanity mirrors, car window glass, and camera lenses, there is a strong demand for providing anti-fogging properties to the surfaces of these substrates.

[0003] The fog that occurs on the main surface of a glass substrate such as a mirror or glass is caused by the condensation phenomenon in which countless minute water droplets form on the substrate surface. To prevent this fog, technologies have been developed to form on the substrate a hydrophilic coating that turns the countless minute water droplets formed on the substrate surface into a uniform water film, and a water-absorbent coating that exhibits anti-fogging properties by absorbing water vapor and water droplets into the coating. Recently, there is a demand for not only antifogging properties but also antifouling properties that prevent the surface of a substrate from being stained. Patent Document 1 describes an antifogging article having a structure in which a polyurethane coating and a coating made of a cured product of a composition containing an antifouling agent are laminated on a substrate in order to impart antifouling properties in addition to antifogging properties. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-4350 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, a polyurethane coating is provided on a substrate, and a coating made of a composition containing an antifouling agent is further laminated on top of the polyurethane coating, thereby producing an antifogging article having excellent antifogging properties and antifouling properties. In Patent Document 1, at least two types of coating agents are required: a coating agent for forming a polyurethane film and a coating agent containing an antifouling agent, and the coating step must be carried out at least twice.

[0006] The present disclosure aims to provide an anti-fogging coating coating agent that can form, with a single liquid, an anti-fogging coating that has excellent anti-fogging and anti-fouling properties (particularly, anti-fouling properties against both oily stains and water stains). In addition, the present disclosure aims to provide a method for producing an anti-fog article, which can produce an anti-fog article having excellent anti-fog and anti-fouling properties (particularly, anti-fouling properties against both oily stains and water stains) through a single coating step. Furthermore, the present disclosure has an object to provide an anti-fogging article having a single-layer anti-fogging coating that is excellent in anti-fogging and anti-soiling properties (particularly, anti-soiling properties against both oily stains and water stains). [Means for solving the problem]

[0007] The problem of the present disclosure is solved by the following configuration.

[0008] [1] (A) a polyisocyanate having two or more isocyanate groups; (B) a polyol having an oxyethylene unit as a repeating unit and having two or more hydroxy groups in the molecule; (C) a first water repellent agent which is a silicone-based acrylic polymer having two or more hydroxyl groups in the molecule; (E) a solvent; A coating agent for forming an anti-fogging film comprising the above compound. [2] The coating agent for forming an anti-fogging film according to [1], wherein the silicone-based acrylic polymer is a copolymer of a silicone monomer and an acrylic monomer. [3] The coating agent for forming an antifogging coating according to [1], further comprising (D) a second water repellent agent which is at least one compound selected from the group consisting of the following (D1), (D2) and (D3): (D1) A compound having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a dialkylsiloxane moiety (SiR 2 O and R each independently represent a linear or branched alkyl group having 1 to 10 carbon atoms) is an average of 1 to 400. (D2) Fluoroalkylsilane having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a fluorocarbon moiety. (D3) A perfluoropolyether having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a fluorocarbon moiety. [4] The coating agent for forming an antifogging coating according to [3], wherein the compound (D1) is a linear polydialkylsiloxane having a structure represented by the following general formula [1-1] or [1-2]:

[0009] [ka]

[0010] In the above general formula [1-1], n is an integer of 5 to 399. R 1 represents a group represented by the following general formula (T1).

[0011] [ka]

[0012] In the above general formula (T1), L 11 , L 12 and L 13 are each independently a single bond or a dialkylsiloxane moiety (SiR 2O and R each independently represent a divalent linking group that does not contain a linear or branched alkyl group having 1 to 10 carbon atoms. R 11 represents a monovalent organic group that does not contain the dialkylsiloxane moiety. * represents a bond.

[0013] [ka]

[0014] In the above general formula [1-2], n is an integer of 1 to 399. R 21 and R 22 each independently represents a group represented by the following general formula (T2).

[0015] [ka]

[0016] In the above general formula (T2), L 21 is a single bond or a dialkylsiloxane moiety (SiR 2 O and R each independently represent a divalent linking group that does not contain a straight-chain or branched alkyl group having 1 to 10 carbon atoms. a represents 1 to 50. b represents 1 to 50. * represents a bond. [5] The coating agent for forming an anti-fogging coating according to [1], wherein the content of the first water repellent (C) is 0.001 to 10.0% by mass relative to 100% by mass of the urethane-forming components. [6] The coating agent for forming an anti-fogging coating according to [1], wherein the content of the second water repellent (D) is 0.001 to 10.0% by mass relative to 100% by mass of the urethane-forming components. [7] The coating agent for forming an antifogging coating according to [1], wherein the polyol (B) comprises (B1) polyethylene glycol and (B2) a copolymer polyol having an oxyethylene unit and an oxypropylene unit as repeating units. [8] The coating agent for forming an anti-fogging film according to [1], further comprising (F) polytetramethylene ether glycol. [9] The coating agent for forming an anti-fogging coating according to [1], further comprising (G) a short-chain polyol having a number average molecular weight of 60 to 200.

[10] Number of isocyanate groups in urethane-forming components n (NCO) and the number of hydroxyl groups in the urethane-forming component, n (OH) The ratio of n (NCO) / n (OH) The coating agent for forming an anti-fogging film according to [1], wherein the viscosity is 1.0 to 3.0.

[11] The coating agent for forming an antifogging coating according to [1], wherein the content of the polyol (B) is 25 to 75% by mass relative to 100% by mass of the urethane-forming components.

[12] A method for producing an anti-fogging article having a substrate and an anti-fogging coating, comprising the steps of: A step (1) of applying the anti-fogging coating agent according to any one of items [1] to

[11] to a surface of a substrate to form a coating film; a step (2) of evaporating the solvent (E) from the coating film and curing the coating film to form an anti-fogging coating film; A method for producing an anti-fogging article comprising the steps of:

[13] The method for producing an anti-fogging article according to

[12] , wherein the substrate is a glass substrate.

[14] The method for producing an anti-fogging article according to

[13] , wherein a silane coupling agent is applied to the surface of the glass substrate.

[15] The method for producing an anti-fogging article according to

[12] , wherein in the step (2), an isocyanate group of the polyisocyanate (A) reacts with a hydroxyl group of the polyol (B) and the first water repellent (C) to form a polyurethane.

[16] The method for producing an anti-fogging article according to

[12] , wherein in the step (2), the coating film is heated at 80 to 170°C.

[17] An anti-fogging article having a substrate and an anti-fogging coating, The anti-fogging coating is a coating containing a polyurethane resin that is a cured product of the coating agent for forming an anti-fogging coating according to any one of [1] to

[11] , The anti-fogging coating has a thickness of 5 μm to 50 μm. Anti-fog articles.

[18] The anti-fogging article according to

[17] , wherein the substrate is a glass substrate.

[19] The anti-fogging article according to

[18] , wherein a silane coupling agent is applied to the surface of the glass substrate. Effect of the Invention

[0017] According to the present disclosure, it is possible to provide an anti-fogging coating forming coating agent that can form, with a single liquid, an anti-fogging coating that has excellent anti-fogging and anti-fouling properties (particularly, anti-fouling properties against both oily stains and water stains). Furthermore, according to the present disclosure, a method for producing an anti-fog article can be provided, which can produce an anti-fog article having excellent anti-fog and anti-fouling properties (particularly, anti-fouling properties against both oily stains and water stains) through a single coating step. Furthermore, according to the present disclosure, it is possible to provide an anti-fogging article having a single-layer anti-fogging coating that is excellent in anti-fogging and anti-soiling properties (particularly, anti-soiling properties against both oily stains and water stains). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] [Anti-fogging coating agent] The coating agent for forming an anti-fogging film according to the present disclosure is (A) a polyisocyanate having two or more isocyanate groups; (B) a polyol having an oxyethylene unit as a repeating unit and having two or more hydroxy groups in the molecule; (C) A silicone-based acrylic polymer having two or more hydroxy groups in the molecule. (E) a solvent; Includes.

[0019] <(A) Polyisocyanate having two or more isocyanate groups> (A) Polyisocyanate having two or more isocyanate groups (also referred to as "polyisocyanate (A)") will be described. The polyisocyanate (A) serves as a framework component of the anti-fogging coating (also simply referred to as a "coating") and can impart water absorbency and hardness to the coating. The polyisocyanate (A) is not particularly limited, and examples thereof include compounds having 2 to 5 isocyanate groups, and specific examples thereof include hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, bis(methylcyclohexyl) diisocyanate, toluene diisocyanate, and the like. The polyisocyanate (A) may be a polymer (e.g., a dimer, a trimer, etc.) or may have at least one structure selected from the group consisting of an allophanate structure, an adduct structure, a biuret structure, and an isocyanurate structure. For example, it may be a dimer using hexamethylene diisocyanate as a starting material, a compound having an allophanate structure using hexamethylene diisocyanate as a starting material, or a compound having a biuret structure using hexamethylene diisocyanate as a starting material. When the polyisocyanate (A) is a polymer, the number average molecular weight is preferably 100 to 20,000, more preferably 150 to 5,000, and particularly preferably 200 to 2,000.

[0020] The isocyanate group of the polyisocyanate (A) may be a blocked isocyanate group. The polyisocyanate (A) having a blocked isocyanate group is also called a "blocked polyisocyanate (AH)".

[0021] A blocked isocyanate group is an isocyanate group protected with a blocking agent, and the blocking agent is dissociated by heat treatment to regenerate the isocyanate group.

[0022] The blocked polyisocyanate (AH) is not particularly limited, and may be, for example, one in which the isocyanate group of the above-mentioned polyisocyanate is protected with a known blocking agent.

[0023] In addition, the blocked polyisocyanate (AH) preferably has a urethane bond (-NHCOO-) in the molecule.

[0024] The number average molecular weight of the blocked polyisocyanate (AH) is preferably 100 to 20,000, more preferably 150 to 5,000, and particularly preferably 200 to 2,000.

[0025] <(B) Polyol Having Oxyethylene Units as Repeating Units and Two or More Hydroxy Groups in the Molecule> (B) A polyol having an oxyethylene unit as a repeating unit and having two or more hydroxy groups in the molecule (also referred to as "polyol (B)") will be described. The polyol (B) can impart water absorbency to the anti-fogging coating by having an oxyethylene unit as a repeating unit. 2 CH 2 O) p -". p represents an integer of 2 or greater. The polyol (B) preferably has three or more hydroxy groups in the molecule. The polyol (B) is not particularly limited, but examples thereof include (B1) polyethylene glycol and (B2) copolymer polyol having oxyethylene units and oxypropylene units as repeating units, and it is preferable to contain both of the above (B1) and (B2).

[0026] The copolymer polyol (B2) can be a polyether polyol obtained by ring-opening polymerization of ethylene oxide and propylene oxide using a phosphazene compound, a Lewis acid compound or an alkali metal compound catalyst as an initiator, followed by block addition or random addition. The molar ratio of oxyethylene units / oxypropylene units in the copolymer polyol (B2) may be from 45 / 55 to 90 / 10, and preferably from 70 / 30 to 80 / 20.

[0027] The number average molecular weight of the polyol (B) is preferably 200-10,000, more preferably 300-5,000, and further preferably 400-2,000.

[0028] The polyol (B) is preferably a branched polyol (a polyol having a branched structure in the molecule) or a cyclic polyol (a polyol having a cyclic structure such as a four-membered ring, a five-membered ring, or a six-membered ring in the molecule). Examples of the branched polyol include trimethylolpropane ethoxylate, pentaerythritol ethoxylate, polyoxyethylene (13) polyglyceryl ether, and the like. Examples of the six-membered ring polyol include polyoxyethylene methyl glucoside (methyl gluceth-10, methyl gluceth-20, and the like), polyoxyethylene sorbitan monolaurate, and the like. In addition, both the branched polyol and the cyclic polyol may be used as the polyol (B).

[0029] Polyol (B) is commercially available, and examples thereof include polyethylene polypropylene glycol (trade name "Toho Polyol PB-4000") manufactured by Toho Chemical Industry Co., Ltd., trimethylolpropane ethoxylate and pentaerythritol ethoxylate (trade name "SCE-750") manufactured by Sigma-Aldrich Co., Ltd., polyoxyethylene (13) polyglyceryl ether (trade name "SCE-750") manufactured by Sakamoto Pharmaceutical Co., Ltd., methyl gluceth-10 (trade name "Macbiobride MG-10E") manufactured by NOF Corp., methyl gluceth-20 (trade name "Macbiobride MG-20E") manufactured by NOF Corp., and polyoxyethylene sorbitan monolaurate (trade name "Polysorbate T-20C") manufactured by Sanyo Chemical Industry Co., Ltd.

[0030] <(C) A first water repellent agent which is a silicone-based acrylic polymer having two or more hydroxyl groups in the molecule> (C) The first water repellent, which is a silicone-based acrylic polymer having two or more hydroxyl groups in the molecule (also referred to as "first water repellent (C)"), will be described. The first water repellent (C) is a component that serves as a skeletal component of the anti-fogging coating and contributes to improving the film hardness, as well as a component that imparts anti-fouling properties (particularly anti-fouling properties against both oily stains and water stains) to the anti-fogging coating. The silicone-based acrylic polymer as the first water repellent (C) has a silicone moiety (dialkylsiloxane moiety (SiR 2 wherein O and R each independently represent an alkyl group) and an acrylic polymer portion, and although the detailed reasons are unclear, it is presumed that by having such a structure, it is possible to exhibit not only high water repellency but also high oil repellency (i.e., it is possible to exhibit high water and oil repellency), and as a result, it is possible to exhibit high stain resistance against both oily stains and water stains.

[0031] The first water repellent (C) is not particularly limited as long as it is a silicone-based acrylic polymer having two or more hydroxyl groups in the molecule, but in a preferred embodiment, it is a copolymer of a silicone monomer and an acrylic monomer. Here, the silicone monomer typically has a dialkylsiloxane moiety (SiR2 O and R each independently represent an alkyl group), and further, 2 =C(R α )-, a group represented by (R α represents a hydrogen atom or an alkyl group). In the silicone monomer having a polymerizable group, when the repeating structure (silicone moiety) of the dialkylsiloxane moiety is a silicone segment having a certain chain length, it can also be used as a macromonomer when producing the first water repellent agent (C) in the form of a graft copolymer. The acrylic monomer typically has a CH group such as a (meth)acryloyl group as a polymerizable group. 2 =C(R α A group represented by -C(=O)- (R α represents a hydrogen atom or an alkyl group). Silicone moiety (repeating structure of dialkylsiloxane moiety) and the above CH 2 =C(R α In this specification, a monomer having a group represented by the formula: -C(=O)- corresponds to the silicone monomer, but does not correspond to the acrylic monomer. In other words, the acrylic monomer is intended to be one that does not have a silicone moiety.

[0032] Examples of the form of the silicone-based acrylic polymer (typically a copolymer of a silicone monomer and an acrylic monomer) include a random copolymer, a block copolymer, and a graft copolymer, and a block copolymer or a graft copolymer is preferable. When the silicone-based acrylic polymer (typically a copolymer of a silicone monomer and an acrylic monomer) is a graft copolymer, one of the main chain and the side chain of the graft copolymer is an acrylic polymer moiety (typically the above-mentioned CH 2 =C(R αIt is preferable that the main chain of the graft copolymer is a polymer segment portion formed by a polymerization reaction of a group represented by the formula (I)-C(=O)-, and the other portion is a silicone portion, and it is more preferable that the main chain of the graft copolymer is a graft copolymer containing an acrylic polymer portion and a side chain containing a silicone portion. In the copolymer of a silicone monomer and an acrylic monomer, it is preferable that at least a portion of the silicone monomer or at least a portion of the acrylic monomer is a monomer having a hydroxy group, and it is more preferable that at least a portion of the acrylic monomer is an acrylic monomer having a hydroxy group.

[0033] Specific examples of the first water repellent (C) include those obtained from acrylic monomers such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, acrylonitrile, methacrylonitrile, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, and N-methylol acrylamide, and silicone monomers such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane. Here, when a hydroxy group is provided to a repeating unit derived from an acrylic monomer, it is preferable that at least a part of the acrylic monomer is an acrylic monomer having a hydroxy group, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, or N-methylol acrylamide.

[0034] Further, examples of the first water repellent (C) include those obtained by further copolymerizing the above-mentioned monomer with an amino group-containing monomer, such as 2-dimethylaminoethyl methacrylate or tert-butylaminoethyl methacrylate, a glycidyl group-containing monomer, such as glycidyl acrylate or glycidyl methacrylate, an amino group-containing monomer, such as acrylamide or methacrylamide, an acid group-containing monomer, such as acrylic acid, methacrylic acid, maleic anhydride, crotonic acid, fumaric acid or itaconic acid, a fumaric acid ester, an itaconic acid ester, or styrene.

[0035] The number average molecular weight of the first water repellent (C) is preferably from 200 to 100,000, more preferably from 500 to 80,000, and further preferably from 1,000 to 60,000.

[0036] The first water repellent (C) can be produced based on known methods (see, for example, JP-B-7-57737 and JP-B-7-91385), such as a method of bonding a silicone moiety (silicone segment) obtained by polymerization of a silicone monomer with an acrylic polymer moiety (acrylic segment) obtained by polymerization of an acrylic monomer using a crosslinking agent (vinyltriethoxysilane, 3-(trimethoxysilyl)propyl methacrylate, etc.), or a method of polymerizing a monomer for synthesizing the other segment in the presence of either a silicone segment or an acrylic segment obtained by prepolymerization of a monomer, and the above-mentioned crosslinking agent. In addition, the first water repellent agent (C) may be a commercially available product. Examples of commercially available products of the first water repellent agent (C) include "Simac US-270 (manufactured by Toagosei Co., Ltd.)" and "8BS-9000 (manufactured by Taisei Fine Chemical Co., Ltd.)".

[0037] <(D) Second Water Repellent> The anti-fogging coating agent of the present disclosure may further contain (D) a second water repellent (also referred to as "water repellent (D)"). The second water repellent (D) is a component that imparts antifouling properties to the antifogging coating. The water repellent (D) is at least one compound selected from the group consisting of the following (D1), (D2), and (D3). (D1) A compound having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a dialkylsiloxane moiety (SiR 2 A linear polydialkylsiloxane (also referred to as "compound (D1)") having an average of 1 to 400 carbon atoms (O and R each independently represent a linear or branched alkyl group having 1 to 10 carbon atoms). (D2) Fluoroalkylsilane having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a fluorocarbon moiety (also referred to as "compound (D2)"). (D3) A perfluoropolyether having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a fluorocarbon moiety (also referred to as "compound (D3)").

[0038] In the above compounds (D1), (D2) and (D3), the functional group that generates a hydroxy group upon hydrolysis includes an alkoxy group, and is preferably a linear or branched alkoxy group having 1 to 6 carbon atoms. Specific examples thereof include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group and a butoxy group.

[0039] (Compound (D1)) Since the compound (D1) has a dialkylsiloxane moiety that has excellent slip properties, it can impart antifouling properties to the coating film. In addition, the coating agent for forming an antifogging film of the present disclosure contains the compound (D1) as the second water repellent (D), so that the antifouling property against oily dirt tends to be improved. Although the detailed reason is unclear, it is presumed that this is because the second water repellent (D) also exhibits water and oil repellency.

[0040] In order to obtain a coating film having better antifouling properties and durability, the compound (D1) should preferably contain a dialkylsiloxane moiety (SiR 2 O) is preferably 20 to 50 on average. SiR 2 R in O is preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0041] As the compound (D1), for example, polydimethylsiloxane represented by any one of the following general formulas [1-1] to [1-3] is preferably used. The compound (D1) is preferably a linear polydimethylsiloxane represented by the following general formula [1-1] or [1-2], and more preferably a linear polydimethylsiloxane represented by the following general formula [1-1].

[0042] [ka]

[0043] In the above general formula [1-1], n is an integer of 5 to 399. R 1 represents a group represented by the following general formula (T1).

[0044] [ka]

[0045] In the above general formula (T1), L 11 , L 12 and L 13 are each independently a single bond or a dialkylsiloxane moiety (SiR 2 O and R each independently represent a divalent linking group that does not contain a linear or branched alkyl group having 1 to 10 carbon atoms. R 11 represents a monovalent organic group that does not contain the dialkylsiloxane moiety. * represents a bond.

[0046] [ka]

[0047] In the above general formula [1-2], n is an integer of 1 to 399. R 21 and R 22 each independently represents a group represented by the following general formula (T2).

[0048] [ka]

[0049] In the above general formula (T2), L 21 is a single bond or a dialkylsiloxane moiety (SiR 2 O and R each independently represent a divalent linking group that does not contain a straight-chain or branched alkyl group having 1 to 10 carbon atoms. a represents 1 to 50. b represents 1 to 50. * represents a bond.

[0050] In the general formula [1-1], n is preferably an integer of 10 to 200, and more preferably an integer of 20 to 100. L in general formula (T1) 11 , L 12 and L 13 Specific examples of the divalent linking group as R include an alkylene group, an ether group, a carbonyl group, and an ester bond. 11 Specific examples of the monovalent organic group as the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group.

[0051] In the general formula [1-2], n is preferably an integer of 1 to 100, and more preferably an integer of 1 to 50. L in general formula (T2) 21 Specific examples of the divalent linking group as include an alkylene group, an ether group, a carbonyl group, an ester bond, etc. a preferably represents 1-30, and b preferably represents 1-30.

[0052] [ka]

[0053] In general formula [1-3], X 1 and X 2 Each of a and b independently represents an integer of 0 to 3, and n represents an integer of 10 to 400, provided that a+b is 1 or more, and X 1 and X 2 At least one of the groups is at least one selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group.

[0054] X 1 and X 2 Specific examples of the monovalent or divalent functional group represented by are a hydroxyl group, an amino group, an epoxy group, a carboxyl group, an acryloyl group, an allyl group, a mercapto group, -C(=O)-OR 1 Group(R 1 represents a linear or branched saturated alkyl group having 1 to 4 carbon atoms), -OC(=O)R 1 Group(R 1 -C(=O)-OR 1 R in the group 1 ), -A 1 -B 1 Group(A 1 represents a divalent organic group, B 1 is a hydroxyl group, an amino group, an epoxy group, -C(=O)-OR 1 Group(R 1 represents a linear or branched saturated alkyl group having 1 to 4 carbon atoms) or -OC(=O)R 1 Group(R 1 -C(=O)-OR 1 R in the group 1 (same as)), -A 1 -C(A 2 )(A 3 B 2 )(A 4 B 3 ) group (A 1 represents a divalent organic group, A 2 represents a hydrogen atom or a monovalent organic group, A3 and A 4 Each of B independently represents a divalent organic group. 2 Or B 3 each independently represents a hydroxy group, an amino group, an epoxy group, a carboxy group, an acryloyl group, an allyl group, a mercapto group, -C(=O)-OR 1 Group (R 1 represents a linear or branched saturated alkyl group having 1 to 4 carbon atoms) or -OC(=O)R 1 Group (R 1 -C(=O)-OR 1 R in the group 1 (same as above).

[0055] For example, the compound (D1) may be a single-end-modified polydialkylsiloxane in which at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group (hereinafter also referred to as a "reactive functional group") is bonded to one of the ends of a linear polydialkylsiloxane (e.g., a linear polydimethylsiloxane represented by the above [1-1], etc.), a double-end-modified polydialkylsiloxane in which reactive functional groups are bonded to both ends of a linear polydialkylsiloxane (e.g., a linear polydimethylsiloxane represented by the above [1-2] or [1-3], etc.), or a side-chain-modified polydialkylsiloxane in which a reactive functional group is bonded directly to a silicon atom constituting the siloxane moiety of a linear polydialkylsiloxane.

[0056] (Compound (D2)) The fluorocarbon moiety in compound (D2) is CF 2 or CF 3 It is preferable that: As the compound (D2), a fluoroalkylsilane having a functional group at one terminal, as represented by the following general formula [2], or a fluoroalkylsilane having functional groups at both terminals, as represented by the following general formula [3], is preferably used.

[0057] [ka]

[0058] In general formula [2], Y 1 Each independently represents a monovalent functional group; p is an integer of 1 to 3 and represents the number of functional groups; and m is an integer of 2 to 6. However, at least one Y 1 represents at least one selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group.

[0059] [ka]

[0060] In general formula [3], Y 2 and Y 3 Each of Y independently represents a monovalent functional group. m is an integer of 2 to 6 and represents the number of fluorocarbon moieties. q and r are each independently an integer of 1 to 3 and represent the number of monovalent functional groups. 2 and Y 3 At least one of represents at least one selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group.

[0061] Compound (D2) has a fluorocarbon moiety that has excellent stain-resistant properties and removability against stain components such as sebum components, fingerprints, and water stains, as well as excellent durability, and is therefore effective in improving the stain-resistant properties and durability of the resulting coating. In addition, the compound (D2) may have a perfluoroalkyl group (CF) having 2 to 6 fluorocarbon moieties in the molecule. 3 (CF 2 ) t-1 -) or perfluoroalkylene group (-(CF 2 ) u Increasing the number of fluorocarbon moieties increases the durability of the resulting antifouling coating. t and u represent integers, and the "-" represents a bond.

[0062] (Compound (D3)) The fluorocarbon moiety in compound (D3) is CF 2 or CF 3 It is preferable that: The compound (D3) is preferably one represented by any one of the following general formulas [4] to [6].

[0063] [ka]

[0064] In general formula [4], Rf 1 is the formula:-C p F 2p A structure represented by -O- (wherein p is an integer of 1 to 6), or -C q F 2q -(q is an integer of 1 to 8). Each Z independently represents a straight or branched alkoxy group having 1 to 6 carbon atoms, specific examples of which include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a butoxy group. R is an alkyl group having 1 to 10 carbon atoms, and a is an integer of 1 to 3. n and n' are each integers of 1 to 5, and m and m' are each integers of 0 to 2.

[0065] [ka]

[0066] In the general formula [5], r represents an integer of 1 to 200. Each Z independently represents a linear or branched alkoxy group having 1 to 6 carbon atoms, and specific examples of the group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a butoxy group.

[0067] [ka]

[0068] In the general formula [6], s represents an integer of 1 to 100, and t represents an integer of 1 to 10. Each Z independently represents a linear or branched alkoxy group having 1 to 6 carbon atoms, and specific examples of the group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a butoxy group.

[0069] Like compound (D2), compound (D3) has a fluorocarbon moiety that has excellent stain-resistant properties and removability against stain components such as sebum components, fingerprints, and water stains, as well as excellent durability, and is therefore effective in improving the stain-resistant properties and durability of the resulting coating.

[0070] <(E) Solvent> (E) Solvent (also referred to as "solvent (E)") will be explained. As the solvent (E), it is preferable to use an acetate-based solvent or a ketone. Specifically, the acetate-based solvent includes amyl acetate, allyl acetate, isoamyl acetate, isobutyl acetate, isopropyl acetate, ethyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, n-butyl acetate, s-butyl acetate, propyl acetate, benzyl acetate, methyl acetate, and methylcyclohexyl acetate. The ketone includes acetylacetone, acetone, isophorone, ethyl-n-butyl ketone, diisobutyl ketone, diisopropyl ketone, diethyl ketone, cyclohexanone, di-n-propyl ketone, methyl oxide, methyl-n-amyl ketone, methyl isobutyl ketone, methyl ethyl ketone, methylcyclohexanone, methyl-n-butyl ketone, methyl-n-propyl ketone, methyl-n-hexyl ketone, methyl-n-heptyl ketone, diacetone alcohol, and mixtures thereof. Particularly, isobutyl acetate, n-butyl acetate, s-butyl acetate, methyl ethyl ketone, and the like are preferred.

[0071] <(F) Polytetramethylene ether glycol> The coating agent for forming an antifogging film of the present disclosure may further contain (F) polytetramethylene ether glycol (also referred to as "polytetramethylene ether glycol (F)"). The number average molecular weight of the polytetramethylene ether glycol (F) is preferably 100 to 4000, more preferably 500 to 2000, and particularly preferably 800 to 1200.

[0072] <(G) Short-chain polyol with a number-average molecular weight of 60 to 200> The coating agent for forming an anti-fogging coating according to the present disclosure may further contain (G) a short-chain polyol having a number average molecular weight of 60 to 200 (also referred to as "short-chain polyol (G)"). The short-chain polyol (G) is a polyol having a number average molecular weight in the range of 60-200 and a short chain length. By including the short-chain polyol (G), the hardness of the coating film is likely to be improved. The number of hydroxyl groups per molecule of the short-chain polyol (G) may be 2 or 3.

[0073] Examples of the short-chain polyol (G) include alkyl polyols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2-butene-1,4-diol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, glycerin, 2-ethyl-2-(hydroxymethyl)-1,3-propanediol, 1,2,6-hexanetriol, and 2,2'-thiodiethanol, and alkanolamines such as diethanolamine and triethanolamine. These may be used alone or in the form of a mixture, or a copolymer having a number average molecular weight of 60 to 200.

[0074] Among these, ethylene glycol and triethylene glycol are preferred from the viewpoint of improving the hardness of the coating film, and short-chain polyols having secondary or tertiary hydroxyl groups that are less active than primary hydroxyl groups, such as 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, and 2,3-butanediol, are preferred from the viewpoint of the stability of the coating solution (extending the pot life).

[0075] <Urethane-forming components> In this specification, the term "urethane-forming components" refers to all components contained in the coating agent for forming an anti-fogging coating of the present disclosure that serve as raw materials for forming polyurethane, excluding the first water repellent (C) and the second water repellent (D). Typically, the "urethane-forming components" refer to the polyisocyanate (A), polyol (B), polytetramethylene ether glycol (F), and short-chain polyol (G) in the coating agent for forming an anti-fogging coating of the present disclosure. When the coating agent for forming an anti-fogging coating according to the present disclosure contains polyisocyanate (A), polyol (B), and first water repellent (C), but does not contain polytetramethylene ether glycol (F) and short-chain polyol (G), the "urethane-forming component" is polyisocyanate (A) and polyol (B). When the coating agent for forming an anti-fogging coating according to the present disclosure contains polyisocyanate (A), polyol (B), first water repellent (C), and second water repellent (D), but does not contain polytetramethylene ether glycol (F) and short-chain polyol (G), the "urethane-forming components" are polyisocyanate (A) and polyol (B). In other cases, the "urethane-forming component" is considered to be the same as above. In addition, even if a compound corresponding to the first water repellent (C) or the second water repellent (D) also corresponds to another component, this compound is treated as not corresponding to the "urethane-forming component" in this specification, since it corresponds to the first water repellent (C) or the second water repellent (D). For example, in determining whether a compound that corresponds to both the second water repellent (D) and the polyol (B) is a "urethane-forming component," it is not considered to be a "urethane-forming component" because it corresponds to the second water repellent (D).

[0076] <Content of each ingredient> The content of the polyisocyanate (A) in the coating agent for forming an anti-fogging coating of the present disclosure is preferably 25 to 75 mass%, more preferably 30 to 70 mass%, and even more preferably 35 to 70 mass%, relative to 100 mass% of the urethane-forming components.

[0077] The content of polyol (B) in the coating agent for forming an anti-fogging coating of the present disclosure is preferably 25 to 75 mass%, more preferably 30 to 70 mass%, and even more preferably 30 to 65 mass%, relative to 100 mass% of the urethane-forming components.

[0078] The content of the first water repellent (C) in the coating agent for forming an anti-fogging coating film of the present disclosure is preferably 0.001 to 10.0 mass%, more preferably 0.005 to 5.0 mass%, and even more preferably 0.01 to 2.0 mass%, relative to 100 mass% of the urethane-forming components.

[0079] The content of the second water repellent (D) in the coating agent for forming an anti-fogging coating film of the present disclosure is preferably 0.001 to 10.0 mass%, more preferably 0.005 to 5.0 mass%, and even more preferably 0.01 to 2.0 mass%, relative to 100 mass% of the urethane-forming components.

[0080] When the coating agent for forming an anti-fogging coating film of the present disclosure contains polytetramethylene ether glycol (F), the content of polytetramethylene ether glycol (F) in the coating agent for forming an anti-fogging coating film of the present disclosure is preferably 5 to 15 mass %, and more preferably 8 to 10 mass %, relative to 100 mass % of the urethane-forming components.

[0081] When the coating agent for forming an anti-fogging coating film of the present disclosure contains a short-chain polyol (G), the content of the short-chain polyol (G) in the coating agent for forming an anti-fogging coating film of the present disclosure is preferably 1 to 15 mass %, more preferably 2 to 10 mass %, and even more preferably 3 to 8 mass %, relative to 100 mass % of the urethane-forming components.

[0082] The content of the solvent (E) in the coating agent for forming an antifogging film of the present disclosure can be adjusted, for example, so that the solid content concentration in the coating agent for forming an antifogging film of the present disclosure is 10 to 50 mass %. The solid content refers to all components in the coating agent for forming an antifogging film of the present disclosure excluding the solvent (E), and the solid content concentration refers to the concentration (content) of the solid content.

[0083] <n (NCO) / n (OH) > The number of isocyanate groups in the urethane-forming component in the coating agent for forming an anti-fogging film of the present disclosure, n (NCO) and the number of hydroxyl groups in the urethane-forming component, n (OH) The ratio of n (NCO) / n (OH) is preferably from 1.0 to 3.0, more preferably from 1.1 to 2.5, and even more preferably from 1.1 to 2.0. The number of blocked isocyanate groups is also determined by the number of isocyanate groups, n (NCO) Included.

[0084] <Other ingredients and their contents> The coating agent for forming an anti-fogging film of the present disclosure may contain a curing catalyst in order to increase the curing speed when the coating film formed by applying the coating agent for forming an anti-fogging film is cured to form an anti-fogging film. When the coating agent for forming an anti-fogging coating film of the present disclosure contains a curing catalyst, the content of the curing catalyst in the coating agent for forming an anti-fogging coating film of the present disclosure is preferably 0.001 to 0.5 mass % relative to 100 mass % of the urethane-forming components. Examples of the curing catalyst include organometallic compounds such as organotin compounds, organotitanium compounds, organozirconium compounds, and organobismuth compounds, as well as amine compounds.

[0085] The coating agent for forming an anti-fogging film of the present disclosure may contain a leveling agent that promotes the smoothness of the coating film on the substrate. When the coating agent for forming an anti-fogging coating film of the present disclosure contains a leveling agent, the content of the leveling agent in the coating agent for forming an anti-fogging coating film of the present disclosure is preferably 0.01 to 0.50 mass%, and more preferably 0.05 to 0.25 mass%, relative to 100 mass% of the urethane-forming components.

[0086] The coating agent for forming an anti-fogging film of the present disclosure may contain additives that improve the heat resistance, weather resistance, and water resistance of the coating film. Examples of the additives include hindered amine-based light stabilizers, benzotriazole-based ultraviolet absorbers, hindered phenol-based antioxidants, carbodiimide-based hydrolysis inhibitors, etc. The additives may be used alone or in combination. When the coating agent for forming an anti-fogging coating of the present disclosure contains the above-mentioned additives, the content of the above-mentioned additives in the coating agent for forming an anti-fogging coating of the present disclosure is preferably 0.2 to 10.0 mass %, and more preferably 0.5 to 2.0 mass %, relative to 100 mass % of the urethane-forming components.

[0087] The uses of the coating agent for forming an anti-fogging coating according to the present disclosure are not particularly limited, and examples thereof include mirrors, window glass, etc. for bathrooms, vanities, etc. for architecture, window glass or mirrors, specifically room mirrors and door mirrors, etc. for vehicles, ships, aircraft, etc., as well as lenses for glasses and cameras, goggles, helmet shields, openings and peepholes in refrigerated showcases, freezer showcases, testing machines, precision instrument cases, etc., road reflectors, displays of mobile communication devices such as mobile phones, etc.

[0088] [Method of manufacturing anti-fogging article] The method for producing an anti-fogging article according to the present disclosure includes the steps of: A method for producing an anti-fogging article having a substrate and an anti-fogging coating, comprising the steps of: A step (1) of applying the anti-fogging coating agent of the present disclosure to a surface of a substrate to form a coating film; a step (2) of evaporating the solvent (E) from the coating film and curing the coating film to form an anti-fogging coating film; The method for producing an anti-fogging article comprises the steps of:

[0089] By carrying out the above steps (1) and (2) in this order, an anti-fogging article can be obtained.

[0090] <Base material> The substrate is preferably a plate-like one, typically glass, which is a soda-lime plate glass commonly used for automobiles, buildings, industrial glass, etc., and is plate glass produced by the float method, duplex method, roll-out method, etc., and the production method is not particularly limited.

[0091] As the type of glass, various types of colored glass such as clear, green, bronze, etc.; various types of functional glass such as UV-cut glass, IR-cut glass, and electromagnetic shielding glass; glass that can be used as fireproof glass such as wired glass, low-expansion glass, and zero-expansion glass; tempered glass and similar glasses; laminated glass and double-insulated glass; mirrors produced by a silver coating method or a vacuum film-forming method; and various glass products such as flat plates and curved plates.

[0092] The thickness of the substrate is not particularly limited, but is preferably from 1 mm to 10 mm, and more preferably from 1 mm to 5 mm. The anti-fogging coating may be formed on only one side of the substrate, or on both sides depending on the application. The anti-fogging coating may be formed on the entire surface or a part of the substrate surface.

[0093] The surface of the glass substrate is preferably coated with a primer component such as a silane coupling agent in order to improve the adhesion between the glass substrate and the antifogging coating. When the silane coupling agent is applied to the substrate, the silane coupling agent may be diluted to about 0.05 to 2.0% by mass with alcohol, water, or the like. Examples of the silane coupling agent include aminosilane, mercaptosilane, and epoxysilane. In particular, a silane coupling agent having an amino group is preferred, and γ-glycidoxypropyltrimethoxy, γ-aminopropyltriethoxysilane, 3-(2-aminoethylamino)propyltriethoxysilane, and the like are particularly preferred. Thus, the step of applying a solution containing the coupling agent to the substrate is a particularly preferred embodiment in which the adhesion between the substrate and the coating is improved.

[0094] It is preferable that the substrate is a glass substrate, and that the surface of the glass substrate is coated with a silane coupling agent having an amino group.

[0095] The substrate may be a glass substrate, a resin film such as polyethylene terephthalate, a resin such as polycarbonate, etc. The antifogging coating may be formed on the surface of these resin transparent substrates to form an antifogging article, which may then be attached to a glass substrate.

[0096] <Process (1)> Step (1) is a step of applying the above-described coating agent for forming an anti-fogging film of the present disclosure to the surface of a substrate to form a coating film. Prior to step (1), the above-mentioned substrate and the above-mentioned coating agent for forming an anti-fogging film of the present disclosure are prepared. The coating agent for forming an anti-fogging film of the present disclosure can be applied to a substrate by known means such as dip coating, flow coating, spin coating, roll coating, spray coating, screen printing, and flexographic printing.

[0097] <Process (2)> Step (2) is a step of evaporating the solvent (E) from the coating film and curing the coating film to form an anti-fogging coating. Curing a coating film specifically refers to reacting the raw materials in the coating film to form polyurethane and solidifying the coating film. In the step (2), it is preferable that an isocyanate group of the polyisocyanate (A) reacts with a hydroxy group of the polyol (B) and the first water repellent (C) to form a polyurethane. In step (2), the coating is left standing at room temperature or is heat-treated at 170° C. or less to cure the coating and evaporate the solvent (E), so that the coating is solidified to become an anti-fogging coating. To promote curing of the coating, heating is preferably performed at 80 to 170°C, more preferably at 100 to 165°C, and even more preferably at 120 to 160°C.

[0098] [Anti-fog articles] The anti-fog article of the present disclosure comprises: An anti-fogging article having a substrate and an anti-fogging coating, The anti-fogging coating is a coating containing polyurethane, which is a cured product of the coating agent for forming an anti-fogging coating according to the present disclosure, The anti-fogging coating has a thickness of 5 μm to 50 μm. It is an anti-fogging article.

[0099] The substrate of the anti-fogging article is as described in [Method of manufacturing an anti-fogging article]. In particular, it is preferable that the substrate is a glass substrate, and that the surface of the glass substrate is coated with a silane coupling agent having an amino group.

[0100] The thickness of the anti-fogging coating is 5 μm to 50 μm, preferably 10 μm to 45 μm, more preferably 15 μm to 40 μm, and particularly preferably 20 μm to 30 μm.

[0101] The pencil hardness of the anti-fogging coating is preferably 2H or more, and more preferably 3H or more. EXAMPLES

[0102] Examples of the present disclosure will be described below, but the present disclosure is not limited to the following examples.

[0103] In this embodiment and comparative example, a coating agent (coating liquid) for forming an anti-fogging film for producing an anti-fogging article was prepared, and the coating film made of the coating liquid applied on a substrate was heat-treated and cured to form an anti-fogging film, thereby producing an anti-fogging article. The preparation method of the coating liquid and the production method of the anti-fogging article are as described below. Next, the quality of the obtained anti-fogging article was evaluated by the method shown below.

[0104] [Thickness of anti-fogging coating]: The thickness of the anti-fogging coating was determined by making an incision in the surface of the anti-fogging coating with a cutter, measuring the step between the anti-fogging coating surface and the substrate surface with a surface roughness meter (Surfcorder ET-4000A manufactured by Kosaka Laboratory), and recording the average value of five points as the thickness of the anti-fogging coating.

[0105] [Appearance evaluation]: The appearance, transparency, and presence or absence of unevenness of the anti-fogging coating were visually evaluated. Those without problems in all respects were rated as passing (○), and those with problems in one or more respects were rated as failing (×).

[0106] [Anti-fogging evaluation]: In a room with a temperature of 10°C and a humidity of 30%, the coating surface of the anti-fogging article is exposed to saturated water vapor at 15°C. The time at which the coating surface begins to fog is regarded as the anti-fogging time of the coating, and those that had an anti-fogging time of more than 5 minutes 30 seconds were regarded as passing (◯), and those that did not were regarded as failing (×).

[0107] [Pencil hardness]: In accordance with JIS K 5600 General testing method for paints (1999), the surface of the anti-fogging coating film was scratched five times with a pencil loaded with a load of 750 g. The hardness of the pencil that did not tear the anti-fogging coating film three or more times was regarded as the pencil hardness of the anti-fogging coating film.

[0108] [Oil-resistant marker test]: The coating surface of the anti-fogging article was soiled with an oil-based marker, and the following [repellency], [wipeability] and [removability] were evaluated.

[0109] [Repelling ability]: Those which repelled the permanent marker were marked with an O, those which rubbed off were marked with a △, and those which did not repel the permanent marker were marked with an X.

[0110] [Wipeability]: Using a fiber made of cellulose fiber (product name "Bencotto", model M-1, 50mm x 50mm, manufactured by Ozu Sangyo Co., Ltd.), wipe the stained area with oil-based marker at 400g / cm 2 Those that glide easily without any snagging are rated as ○, those that glide a little are rated as △, and those that do not glide at all are rated as ×.

[0111] [Removability]: Using a BEMCOT, remove oil-based marker stains at 400g / cm 2 The stains from the oil-based marker were wiped back and forth five times with a force of 0.05 mm. Those that could be completely removed were rated as ◯, those that could be removed but the stain remained on the film were rated as △, and those that could not be removed were rated as ×.

[0112] [Water stain resistance test]: Tap water was dropped onto the surface of the anti-fogging coating placed horizontally, and it was then dried for one hour at 60°C. After drying, those where the water stains could be removed were rated as passing (○), and those where they could not be removed were rated as failing (×).

[0113] [Example 1] (Preparation of anti-fog coating solution) As polyisocyanate (A), 38.22 g of blocked isocyanate (product name "Duranate SBB-70P"; solid content concentration 70 mass%; manufactured by Asahi Kasei) was prepared. This was designated as agent A.

[0114] In addition, the following components were mixed in the amounts specified below to obtain Drug B with a total weight of 62.388 g. <Solvent (E)> Mixture of isobutyl acetate and diacetone alcohol; 48.53 g <Polyol (B)> Methyl gluceth-10, a tetrafunctional polyol with a number average molecular weight of 634 and the following structure (trade name "Macbiobride MG-10E"; NOF Corp., a six-membered ring polyol); 13.25 g

[0115] [ka]

[0116] a, b, c, and d are positive integers, and a+b+c+d=10.

[0117] <First Water Repellent (C)> Silicone-based acrylic polymer Symac US-270 (manufactured by Toagosei): 0.20 g <Second Water Repellent (D)> X-22-176DX (Shin-Etsu Chemical Co., Ltd.), a polydimethylsiloxane compound modified with diol at one end: 0.008 g <Light stabilizer> Hindered amine light stabilizer Adeka STAB LA-72 (ADEKA); 0.40g

[0118] The above-mentioned Agent A and Agent B were mixed, and 0.02 g of dibutyltin dilaurate (hereinafter, referred to as DBTDL) was added as a curing catalyst to prepare 100.628 g of Coating Solution 2.

[0119] When the total amount of Coating Liquid 2 was 100% by mass, the amount of urethane-forming components in Coating Liquid 2 was 40% by mass. Furthermore, the number of isocyanate groups was 1.1 times the number of hydroxyl groups in the polyol on a raw material basis for Coating Liquid 2. In Coating Liquid 2, the amount of isocyanate compounds was 66.9% by mass relative to the total amount of urethane-forming components (100% by mass).

[0120] (Preparation of the substrate) A mirror was prepared by forming a silver film on the back of a rectangular soda lime glass plate with a size of 100 mm x 100 mm x 5 mm (thickness) in a normal manner. A mixed solution of 89 g of ion-exchanged water, 10 g of propanol, and 1 g of an amino-silane coupling agent, 3-aminopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), was prepared. The glass surface of the mirror was wiped with a wiper (trade name "Bencotto", model M-1, 50 mm x 50 mm, manufactured by Ozu Sangyo Co., Ltd.) made of cellulose fiber impregnated with the mixed solution, and then washed with water to prepare a mirror with a primer layer formed thereon as a substrate.

[0121] (Formation of anti-fogging article) The coating solution 2 was applied by spin coating to the main surface of the substrate on which the primer layer was formed to form a coating film, and then heat-treated at about 170° C. for about 10 minutes to obtain an anti-fogging article having an anti-fogging coating film with a thickness of 25 μm. The evaluation results of the anti-fogging article of this example were good, as shown in Table 1.

[0122] [Example 2] An anti-fogging article was obtained in the same manner as in Example 1, except that the first water repellent agent was a silicone-based acrylic polymer 8BS-9000 (manufactured by Taisei Fine Chemical).

[0123] [Example 3] An anti-fogging article was obtained by carrying out the same operation as in Example 1, except that only the first water repellent agent was added and no second water repellent agent was added.

[0124] [Example 4] An anti-fogging article was obtained in the same manner as in Example 1, except that the second water repellent was a polydimethylsiloxane compound KF-6123 (manufactured by Shin-Etsu Chemical Co., Ltd.) modified at both ends with polyether.

[0125] [Example 5] An anti-fogging article was obtained in the same manner as in Example 1, except that the second water repellent was a side-chain carbinol-modified polydimethylsiloxane compound X-22-4039 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0126] [Comparative Example 1] An anti-fogging article was obtained by the same operation as in Example 1, except that the first water repellent agent and the second water repellent agent were not added. As shown in Table 1, the evaluation results of the anti-fogging article of this comparative example were inferior to those of the examples in terms of repellency, wiping ability, removability, and water stain removal ability of permanent marker.

[0127] The contents of the first water repellent (C) and the second water repellent (D) in Table 1 below are values ​​relative to 100% by mass of the urethane-forming components.

[0128] [Table 1] [Industrial Applicability]

[0129] The anti-fogging article of the present disclosure can be used for architectural purposes such as mirrors and window glass for bathrooms and vanities, and for vehicles, ships, aircraft, etc. such as window glass or mirrors, specifically, rear-view mirrors, door mirrors, etc. In addition, the anti-fogging article can be used for lenses of glasses and cameras, goggles, helmet shields, openings and peepholes of refrigerated showcases, freezer showcases, testing machines, precision instrument cases, etc., road reflectors, displays of mobile communication devices such as mobile phones, etc.

Claims

1. (A) a polyisocyanate having two or more isocyanate groups; (B) a polyol having an oxyethylene unit as a repeating unit and having two or more hydroxy groups in the molecule; (C) a first water repellent agent which is a silicone-based acrylic polymer having two or more hydroxyl groups in the molecule; (E) a solvent; and A coating agent for forming an anti-fogging film comprising the above compound.

2. 2. The coating agent for forming an anti-fogging film according to claim 1, wherein the silicone-based acrylic polymer is a copolymer of a silicone monomer and an acrylic monomer.

3. The coating agent for forming an anti-fogging coating according to claim 1, further comprising (D) a second water repellent agent which is at least one compound selected from the group consisting of the following (D1), (D2) and (D3): (D1) A siloxane having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a dialkylsiloxane moiety (SiR ２ each of O and R independently represents a linear or branched alkyl group having 1 to 10 carbon atoms) is an average of 1 to 400. (D2) Fluoroalkylsilane having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a fluorocarbon moiety. (D3) A perfluoropolyether having at least one group selected from the group consisting of a hydroxy group, a functional group that generates a hydroxy group upon hydrolysis, a carboxy group, an amino group, and an isocyanate group, and having a fluorocarbon moiety.

4. The coating agent for forming an antifogging coating according to claim 3, wherein the compound (D1) is a linear polydialkylsiloxane having a structure represented by the following general formula [1-1] or [1-2]: 【Chemistry 1】 In the above general formula [1-1], n is an integer of 5 to 399. R １ represents a group represented by the following general formula (T1). 【Chemistry 2】 In the above general formula (T1), L １１ , L １２ and L １３ each independently represents a single bond or a dialkylsiloxane moiety (SiR ２ O and R each independently represent a divalent linking group that does not contain a linear or branched alkyl group having 1 to 10 carbon atoms. R １１ represents a monovalent organic group that does not contain the dialkylsiloxane moiety. * represents a bond. 【Chemistry 3】 In the above general formula [1-2], n is an integer of 1 to 399. R ２１ and R ２２ each independently represents a group represented by general formula (T2) below. 【Chemistry 4】 In the above general formula (T2), L ２１ is a single bond or a dialkylsiloxane moiety (SiR ２ O and R each independently represent a divalent linking group that does not contain a linear or branched alkyl group having 1 to 10 carbon atoms. a represents 1 to 50. b represents 1 to 50. * represents a bond.

5. The coating agent for forming an anti-fogging film according to claim 1, wherein the content of the first water repellent (C) is 0.001 to 10.0% by mass based on 100% by mass of the urethane-forming components.

6. The coating agent for forming an antifogging film according to claim 1, wherein the content of the second water repellent (D) is 0.001 to 10.0% by mass based on 100% by mass of the urethane-forming components.

7. 2. The coating agent for forming an antifogging coating according to claim 1, wherein the polyol (B) comprises (B1) polyethylene glycol and (B2) a copolymer polyol having an oxyethylene unit and an oxypropylene unit as repeating units.

8. The coating agent for forming an anti-fogging film according to claim 1 , further comprising (F) polytetramethylene ether glycol.

9. The coating agent for forming an anti-fogging film according to claim 1, further comprising (G) a short-chain polyol having a number average molecular weight of 60 to 200.

10. Number of isocyanate groups in the urethane-forming component n （ＮＣＯ） and the number of hydroxyl groups in the urethane-forming component, n （ＯＨ） The ratio of （ＮＣＯ） / n （ＯＨ） The coating agent for forming an antifogging film according to claim 1, wherein the viscosity is 1.0 to 3.

0.

11. 2. The coating agent for forming an antifogging film according to claim 1, wherein the content of the polyol (B) is 25 to 75% by mass based on 100% by mass of the urethane-forming components.

12. A method for producing an anti-fogging article having a substrate and an anti-fogging coating, comprising the steps of: A step (1) of applying the coating agent for forming an anti-fogging film according to any one of claims 1 to 11 to a surface of a substrate to form a coating film; (2) a step of evaporating the solvent (E) from the coating film and curing the coating film to form an anti-fogging coating film; A method for producing an anti-fogging article comprising the steps of:

13. The method for producing an anti-fogging article according to claim 12, wherein the substrate is a glass substrate.

14. The method for producing an anti-fogging article according to claim 13, wherein a silane coupling agent is applied to a surface of the glass substrate.

15. The method for producing an anti-fogging article according to claim 12, wherein in the step (2), an isocyanate group of the polyisocyanate (A) reacts with a hydroxyl group of the polyol (B) and the first water repellent (C) to form a polyurethane.

16. The method for producing an anti-fogging article according to claim 12, wherein in the step (2), the coating film is heated at 80 to 170°C.

17. An anti-fogging article having a substrate and an anti-fogging coating, The anti-fogging coating is a coating containing a polyurethane resin that is a cured product of the coating agent for forming an anti-fogging coating according to any one of claims 1 to 11, The anti-fogging coating has a thickness of 5 μm to 50 μm. Anti-fog articles.

18. The anti-fog article according to claim 17, wherein the substrate is a glass substrate.

19. The anti-fogging article according to claim 18 , wherein a silane coupling agent is applied to a surface of the glass substrate.

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