JP6464652B2 - Aqueous resin composition, coating agent and optical film - Google Patents

Description

  The present invention relates to an aqueous resin composition that can be used for various applications such as coating materials, adhesives, and molding materials such as films.

  In recent years, application of aqueous urethane resin compositions to films and sheets for optical applications has been studied. Specific examples of the optical application include a liquid crystal display and a touch panel. The display device such as the liquid crystal display is usually configured by laminating a large number of optical films having various functions in order to display clear images. Examples of the optical film include an antireflection film, a retardation film, and a prism. A lens sheet etc. are mentioned.

  Examples of the aqueous urethane resin composition capable of producing a film such as an optical film include, for example, a polyester composed of an acid component containing an aromatic dicarboxylic acid and an aliphatic (ring) group dicarboxylic acid in a specific ratio, and a glycol component. It is obtained by reacting a polyol, a polyisocyanate, and, if necessary, a chain extender, contains 0.5 to 6% by mass of a pendant carboxyl group, and the carboxyl group is neutralized by ammonium or the like. An aqueous polyester polyurethane resin is known (for example, see Patent Document 1).

  However, in the case of the aqueous polyester polyurethane resin composition as described above, it is difficult to form a film or a coating film having a high refractive index of about 1.53 to 1.63 at a level usable for optical applications. was there. In addition, since the formed film or coating film obtained using the aqueous urethane resin composition is not sufficient in terms of hardness, for example, it is easily damaged when used for a surface coating agent such as a touch panel, poor appearance, etc. Could cause.

JP-A-61-36314

  The problem to be solved by the present invention is a film having high refractive index performance of a level usable for optical applications, excellent in hardness, elongation and flexibility, solvent resistance and adhesion to a substrate, It is to provide an aqueous resin composition capable of forming a coating film or the like.

  As a result of intensive studies to solve the above problems, the present inventors have found that a polyol as a raw material for a urethane resin is an alkylene diol having 1 to 9 carbon atoms and having 2 or more polymerizable unsaturated groups (a1- 1) or an aqueous solution containing a urethane resin (A) using an oxyalkylene diol (a1-2) having 1 to 5 carbon atoms having two or more polymerizable unsaturated groups and an aromatic compound (B) It has been found that the above problems can be solved by using a resin composition, and the present invention has been completed.

  That is, the present invention is an alkylene diol (a1-1) having two or more polymerizable unsaturated groups represented by the following general formula (1) or two or more polymerizable groups represented by the following general formula (2). Urethane resin (A) having a polymerizable unsaturated group obtained by reacting polyol (a1) containing oxyalkylenediol (a1-2) having a saturated group with polyisocyanate (a2), aromatic compound ( The present invention relates to an aqueous resin composition comprising B) and an aqueous medium (C).

(R ¹ in the general formula (1) represents a structure having two or more atomic groups containing a polymerizable unsaturated group in the side chain of the linear alkylene group having 1 to 9 carbon atoms.)

(R ¹ and R ³ in the general formula (2) represent a structure having a total of two or more atomic groups containing a polymerizable unsaturated group in the side chain of the ethylene group. R ² has 1 to 5 carbon atoms. Represents an alkylene group.)

  The aqueous resin composition of the present invention has a high refractive index performance and can form a coating film excellent in hardness, elongation and flexibility, solvent resistance and adhesion to a substrate. It can be suitably used for the production of optical films and lenses used for the production of polarizing plates and the like, coating agents for forming surface protective layers thereof, and coating agents for suppressing interference fringes resulting from the difference in refractive index.

  The aqueous resin composition of the present invention comprises an alkylene diol (a1-1) having two or more polymerizable unsaturated groups represented by the following general formula (1) or two or more represented by the following general formula (2). Urethane resin (A) having a polymerizable unsaturated group obtained by reacting polyol (a1) containing oxyalkylene diol (a1-2) having a polymerizable unsaturated group and polyisocyanate (a2), cross-linking It contains an agent (B) and an aqueous medium (C).

  As the urethane resin (A), among the urethane resins having a polymerizable unsaturated group, an alkylene diol (a1-1) having two or more polymerizable unsaturated groups represented by the following general formula (1) or the following What is obtained by reacting polyol (a1) containing oxyalkylenediol (a1-2) having two or more polymerizable unsaturated groups represented by general formula (2) and polyisocyanate (a2) use.

(R ¹ in the general formula (1) represents a structure having two or more atomic groups containing a polymerizable unsaturated group in the side chain of a linear alkylene group having 1 to 9 carbon atoms.)

(R ¹ and R ³ in the general formula (2) represent a structure having a total of two or more atomic groups containing a polymerizable unsaturated group in the side chain of the ethylene group. R ² has 1 to 5 carbon atoms. Represents an alkylene group.)

  As the polyol (a1) used for the production of the urethane resin (A), two or more polymerizable unsaturated groups are present in the side chain with respect to the main chain of the urethane resin (A) in which urethane bonds are mainly present. For the purpose of introduction, alkylene diol (a1-1) having two or more polymerizable unsaturated groups represented by the general formula (1) or two or more polymerizable compounds represented by the general formula (2) What contains the oxyalkylenediol (a1-2) which has an unsaturated group is used. The polymerizable unsaturated group derived from the alkylene diol (a1-1) and the oxyalkylene diol (a1-2) undergoes radical polymerization when forming a coating film or the like. Thereby, the coating film excellent in hardness, elongation, and flexibility can be formed.

As said alkylene diol (a1-1), what has the structure shown by the said General formula (1) can be used. R ¹ in the general formula (1) represents a structure having two or more atomic groups containing a polymerizable unsaturated group in the side chain of a linear alkylene group having 1 to 9 carbon atoms. For example, pentaerythritol di (meth) acrylate has a structure in which R ¹ in the general formula (1) has two atomic groups containing a polymerizable unsaturated group in the side chain of a propylene group having 3 carbon atoms.

  As the alkylene diol (a1-1), those having 2 or more and 5 or less polymerizable unsaturated groups are preferably used, and those having 2 or more and 3 or less polymerizable unsaturated groups are used. It is more preferable to obtain an aqueous resin composition capable of forming a coating film excellent in hardness, elongation and flexibility.

Examples of the alkylene diol (a1-1) include pentaerythritol di (meth) acrylate [dimethylolpropane di (meth) acrylate], dimethylolmethane di (meth) acrylate (R ¹ in the general formula (1) is , Those having 3 carbon atoms and two atomic groups having a polymerizable unsaturated group), diethylolmethane di (meth) acrylate, and diethylolpropane di (meth) acrylate (general formula (1 R ¹ is a group having 5 carbon atoms and having two atomic groups having a polymerizable unsaturated group.), Dipropanolmethane di (meth) acrylate, dipropanolpropanedi (meth) acrylate (formula (1) R ¹ in the intended 7 carbon atoms, is an atomic group having a polymerizable unsaturated group as it has two.) Di-butanol methane di (meth) acrylate, R ¹ in the di-butanol propane di (meth) acrylate (Formula (1) is of a carbon atoms 9 and has two atomic group having a polymerizable unsaturated group Etc.). Among them, since pentaerythritol di (meth) acrylate and dimethylolmethane di (meth) acrylate are used, an aqueous resin composition capable of forming a coating film excellent in hardness, elongation and flexibility can be obtained. More preferable. These alkylene diols (a1-1) can be used alone or in combination of two or more. In the present invention, “(meth) acrylate” refers to either one or both of acrylate and methacrylate.

Moreover, as said oxyalkylene diol (a1-2), what has the structure shown by the said General formula (2) can be used. R ¹ and R ³ in the general formula (2) have a structure having an atomic group containing a polymerizable unsaturated group in the side chain of the ethylene group. In the general formula (2), it has a total of two or more structures having an atomic group containing a polymerizable unsaturated group in the side chain of the ethylene group, preferably in the range of 2 or more and 5 or less, More preferably, it has in the range of 2 or more and 3 or less.

R ² in the general formula (2) represents an alkylene group having 1 to 5 carbon atoms, and examples thereof include a methylene group, an ethylene group, a propylene group, a butylene group, and a pentyl group.

Examples of the oxyalkylene diol (a1-2) include bis (3-acryloyloxy-2-hydroxypropoxy) methane (R ¹ and R ³ in the general formula (2) are those having 2 carbon atoms and are polymerizable. It has one atomic group having an unsaturated group, and R ² has 1 carbon atom.) 1,2-bis (3-acryloyloxy-2-hydroxypropoxy) ethane (general formula (2 And R ¹ and R ³ are those having 2 carbon atoms and having one atomic group having a polymerizable unsaturated group, and R ² is having 2 carbon atoms.), 1, 3-bis (3-acryloyloxy-2-hydroxypropoxy) propane (in the general formula (2), R ¹ and R ³ have 2 carbon atoms and have one atomic group having a polymerizable unsaturated group) in and, ^{R 2} is the number of carbon atoms Is of.), 1,4-bis (3-acryloyloxy-2-hydroxypropoxy) butane (formula (2) ^{R 1} and ^{R 3} in the intended 2 carbon atoms, a polymerizable unsaturated group And R ² has 4 carbon atoms.) 1,5-bis (3-acryloyloxy-2-hydroxypropoxy) pentane (in the general formula (2)) R ¹ and R ³ have 2 carbon atoms, have 1 atomic group having a polymerizable unsaturated group, and R ² has 5 carbon atoms). Among these, the use of bis (3-acryloyloxy-2-hydroxypropoxy) methane is more preferable because an aqueous resin composition capable of forming a coating film excellent in hardness, elongation and flexibility is obtained. Moreover, these oxyalkylene diols (a1-2) can be used alone or in combination of two or more.

  The said alkylene diol (a1-1) and the said oxyalkylene diol (a1-2) are used in the range of 0.1-49 mass% in total in the whole quantity of the raw material used for manufacture of the said urethane resin (A). Is more preferable, since it is possible to obtain an aqueous resin composition capable of forming a coating film excellent in hardness, elongation and flexibility, and more preferably in the range of 1 to 15% by mass. In addition, the total amount of the raw material used for manufacture of the said urethane resin (A) points out the total mass containing it, when a polyol (a1), polyisocyanate (a2), and a chain extender are used.

  As the polyol (a1) that can be used for the production of the urethane resin (A), other polyols may be used in combination with the alkylene diol (a1-1) and the oxyalkylene diol (a1-2) as necessary. be able to.

  As the other polyol, a polyol having an aromatic ring and / or a polyol having a sulfur atom is used for the purpose of imparting a high refractive index performance to a coating film obtained using the aqueous resin composition of the present invention. be able to.

  Examples of the polyol having an aromatic ring include aromatic polyester polyols, aromatic polycarbonate polyols, aromatic polyether polyols, and bisphenol alkylene oxide adducts. These polyols having an aromatic ring can be used alone or in combination of two or more.

  The bisphenol alkylene oxide adduct is obtained by adding alkylene oxide to the phenolic hydroxyl group of bisphenol. Examples of the alkylene oxide adduct of bisphenol include an alkylene oxide adduct of bisphenol A, an alkylene oxide adduct of bisphenol F, and an alkylene oxide adduct of bisphenol S. Examples of the alkylene oxide include ethylene oxide and propion oxide.

  As the other polyol, a polyol having a sulfur atom can be used in addition to the polyol having an aromatic ring.

  Examples of the polyol having a sulfur atom include bis (2-hydroxyethyl) sulfide and 2,5-dihydroxy-1,4-dithiane.

  In addition to the polyol having the aromatic ring and the polyol having the sulfur atom, the other polyol may be hydrophilic, for example, for the purpose of imparting excellent water dispersion stability to the urethane resin (A). The polyol which has group is mentioned.

  Examples of the polyol having a hydrophilic group include a polyol having an anionic group, a polyol having a cationic group, and a polyol having a nonionic group. Of these, polyols having an anionic group are preferred.

  Examples of the polyol having an anionic group include a polyol having a carboxyl group and a polyol having a sulfonic acid group.

  Examples of the polyol having a carboxyl group include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolvaleric acid, and the like, among others, 2,2-dimethylol. Propionic acid is preferred. Moreover, the polyester polyol which has a carboxyl group obtained by making the polyol which has the said carboxyl group, and various polycarboxylic acids react can also be used.

  Examples of the polyol having a sulfonic acid group include dicarboxylic acids such as 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, 5- (4-sulfophenoxy) isophthalic acid, and salts thereof; Polyester polyol obtained by reacting low molecular polyols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, and the like, and the polyester polyol and γ-butyrolactone And polyester polyols obtained by reacting cyclic ester compounds such as δ-valerolactone and ε-caprolactone.

  The anionic groups are preferably partially or wholly neutralized with a basic compound or the like in order to exhibit good water dispersibility.

  Examples of basic compounds that can be used when neutralizing the anionic group include organic amines having a boiling point of 200 ° C. or higher, such as ammonia, triethylamine, morpholine, monoethanolamine, diethylethanolamine; sodium hydroxide, water Examples thereof include metal hydroxides including potassium oxide and lithium hydroxide. From the viewpoint of improving the water dispersion stability of the obtained aqueous resin composition, the basic compound is [basic compound / (total amount of acid groups such as carboxyl groups)] = 0.5 to 3 (molar ratio). It is preferable to use in the range which becomes, and it is more preferable to use in the range used as 0.7-1.5 (molar ratio).

  Examples of the polyol having a cationic group include a polyol having a tertiary amino group. Specific examples include N-methyl-diethanolamine and polyols obtained by reacting a compound having two epoxies with a secondary amine.

  It is preferable that a part or all of the cationic group is neutralized with an acidic compound such as formic acid, acetic acid, propionic acid, succinic acid, glutaric acid, tartaric acid, adipic acid, and phosphoric acid.

  Further, the tertiary amino group as the cationic group is preferably partly or entirely quaternized. Examples of the quaternizing agent include dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride and the like, and dimethyl sulfate is preferable.

  Examples of the polyol having a nonionic group include polyalkylene glycol having a structural unit derived from ethylene oxide.

  The polyol having a hydrophilic group is preferably used in the range of 1 to 20% by mass in the total amount of raw materials used for the production of the urethane resin (A), and further in hardness, elongation and flexibility. Since the aqueous resin composition which can form the outstanding coating film is obtained, it is more preferable to use in the range of 1-10 mass%.

  Moreover, as said other polyol, since the coating film excellent in hardness, elongation, and flexibility can be formed, polyester polyol, polycarbonate polyol, polyether polyol etc. are mentioned, for example. Among these, polyester polyol and polycarbonate polyol are preferable.

  Examples of the polyester polyol include a polyester polyol obtained by reacting a low molecular weight polyol and a polycarboxylic acid; a polyester polyol obtained by a ring-opening polymerization reaction of a cyclic ester compound such as ε-caprolactone; Examples include polyester polyols obtained by polymerization.

  Examples of the low molecular weight polyol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, 1,3-butanediol and the like having a molecular weight of about 50 to 300. An aliphatic polyol having a cyclic structure such as cyclohexanedimethanol

  Examples of the polycarboxylic acid that can be used for the production of the polyester polyol include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid; terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid. And aromatic polycarboxylic acids such as anhydrides or esterified products thereof.

  Examples of the polycarbonate polyol include diols such as 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and cyclohexanedimethanol, carbonate esters such as dimethyl carbonate and diethyl carbonate, and phosgene. And the like obtained by reacting with the above.

  The polyester polyol, polyether polyol and polycarbonate polyol are preferably used in the range of 1 to 70% by mass in the total amount of raw materials used for the production of the urethane resin (A), and in the range of 15 to 45% by mass. It is more preferable to use in the case of being able to form a coating film having excellent hardness, elongation and flexibility.

  Examples of the polyisocyanate (a2) used in the production of the urethane resin (A) include polyisocyanates having an aliphatic cyclic structure such as cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate; 4,4′-diphenylmethane Aromatic polyisocyanates such as diisocyanate, 2,4′-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, phenylene diisocyanate, tolylene diisocyanate, naphthalene diisocyanate; hexamethylene diisocyanate, lysine diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate Aliphatic polyisocyanates such as isocyanate Sulfonate, and the like. Especially, it is preferable to use an aromatic polyisocyanate because a coating film having a high refractive index performance can be formed. Moreover, these polyisocyanates (a2) can be used alone or in combination of two or more.

  As a method for producing the urethane resin (A) by reacting the polyol (a1) and the polyisocyanate (a2), for example, the polyol (a1) and the polyisocyanate are used in the absence of a solvent or in the presence of an organic solvent. (A2) is mixed and the method of making it react in reaction temperature range of about 50 to 150 degreeC is mentioned.

  In the reaction of the polyol (a1) and the polyisocyanate (a2), for example, the equivalent ratio of the isocyanate group of the polyisocyanate (a2) to the hydroxyl group of the polyol (a1) is in the range of 0.8 to 2.5. Preferably, it is carried out in the range of 0.9 to 1.5.

  Moreover, when manufacturing the said urethane resin (A), since the coating film excellent in hardness, elongation, and flexibility can be formed, in addition to the said polyol (a1) and the said polyisocyanate (a2), it is necessary. Depending on the chain extender can be used.

  As a chain extender that can be used when producing the urethane resin (A), polyamines, hydrazine compounds, other active hydrogen atom-containing compounds, and the like can be used.

  Examples of the polyamine include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4′-dicyclohexylmethanediamine, and 3,3′-. Diamines such as dimethyl-4,4′-dicyclohexylmethanediamine, 1,4-cyclohexanediamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, N-ethylaminoethylamine, N -Methylaminopropylamine; diethylenetriamine, dipropylenetriamine, triethylenetetramine and the like. Moreover, these polyamines can be used alone or in combination of two or more.

  Examples of the hydrazine compound include hydrazine, N, N′-dimethylhydrazine, 1,6-hexamethylenebishydrazine; succinic acid dihydrazide, adipic acid dihydrazide, glutaric acid dihydrazide, sebacic acid dihydrazide, isophthalic acid dihydrazide; β-semicarbazide And propionic acid hydrazide. Moreover, these hydrazine compounds can be used alone or in combination of two or more.

  Examples of the other active hydrogen-containing compounds include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, saccharose, Glycols such as methylene glycol, glycerin and sorbitol; bisphenol A, 4,4′-dihydroxydiphenyl, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl sulfone, hydrogenated bisphenol A, phenol such as hydroquinone, and water These can be used, and the aqueous resin composition of the present invention can be used alone or in combination of two or more within the range in which the storage stability does not deteriorate.

  Examples of the organic solvent that can be used in producing the urethane resin (A) include ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran and dioxane; acetate solvents such as ethyl acetate and butyl acetate; acetonitrile and the like. Nitrile solvents of the following: amide solvents such as dimethylformamide and N-methylpyrrolidone. These organic solvents can be used alone or in combination of two or more.

  In addition, in order to reduce the burden on safety and the environment, the organic solvent removes part or all of the organic solvent by, for example, distilling under reduced pressure during or after the production of the urethane resin (A). May be.

  Since the urethane resin (A) obtained by the above method can form a coating film having excellent hardness, elongation and flexibility, it is preferable to use a resin having a weight average molecular weight in the range of 10,000 to 500,000. It is preferable to use those having a weight average molecular weight in the range of 20,000 to 200,000, and it is more preferable to use a weight average molecular weight in the range of 40,000 to 100,000.

  Moreover, as said urethane resin (A), since it can form the coating film excellent in hardness, elongation, and flexibility, it is preferable to use what has a urea bond.

  As the urethane resin (A), it is preferable to use a resin having a urea bond equivalent in the range of 500 to 50,000 because a coating film excellent in hardness, elongation and flexibility can be formed.

  The urethane resin (A) preferably contains the urethane resin (A) in a range of 5 to 85% by mass in the total amount of the aqueous resin composition. It is preferable to contain.

  The aromatic compound (B) used in the present invention is used for the purpose of imparting high refractive index performance to the coating film obtained using the aqueous resin composition of the present invention. Moreover, what has at least 1 or more of an aromatic ring can be used for the said aromatic compound (B). In addition, what has an aromatic ring as said urethane resin (A) and what uses an aromatic compound as an aqueous medium (C) mentioned later shall not be contained in the said aromatic compound (B).

  Examples of the aromatic compound (B) include styrene, phenol, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N, N-dimethyl-p-aminoethylstyrene, N, 6-membered aromatic compounds such as N-diethyl-p-aminoethylstyrene, 2-phenoxyethyl acrylate, bisphenol A, bisphenol F, etc., 6-membered aromatic hetero compounds such as pyridine, pyrazine, 1,2,3-triazine, etc. Ring compounds, five-membered aromatic heterocyclic compounds such as thiophene, bithiophene, thiazole, dithienyl sulfide, ethoxylated o-phenylphenol acrylate, naphthalenediol, anthracenediol, quinoline, buteridine, phenoxazine, fluorene, 9,9- Bis [4- (2-acryloyl ) Phenyl] such as polycyclic aromatic compounds fluorene, and the like. Among them, an aromatic compound having two or more aromatic rings such as ethoxylated o-phenylphenol acrylate and 9,9-bis [4- (2-acryloyloxy) phenyl] fluorene has a higher refractive index. It is preferable because a film can be formed.

  Moreover, since the higher refractive index can be provided to the coating film obtained using the aqueous resin composition of the present invention as the aromatic compound (B), an aromatic compound containing a sulfur atom may be used. it can. Examples of the aromatic compound containing a sulfur atom include sulfide compounds such as diphenyl sulfide, bis (4-hydroxyphenyl) sulfide, and diphenyl sulfide, and sulfonyl compounds such as diphenyl sulfone, methylphenyl sulfone, and bisphenol S. .

  Moreover, as said aromatic compound (B), what has a functional group which can react with the said urethane resin (A) is preferable from the ability to form the coating film which was more excellent in coating-film hardness and solvent resistance.

  Examples of the functional group that can react with the urethane resin (A) of the aromatic compound (B) include a vinyl group, a (meth) acryloyl group, an amino group, an epoxy group, a hydroxy group, a mercapto group, and an isocyanate group. Is mentioned. In the present invention, the “(meth) acryloyl group” means either one or both of an acryloyl group and a methacryloyl group.

  The concentration of the aromatic ring in the aqueous resin composition of the present invention is such that the aromatic ring concentration in the nonvolatile content of the aqueous resin composition is in the range of 0.5 to 15 mol / kg. It is preferable because it can be formed, and more preferably in the range of 3 to 10 mol / kg.

  Examples of the aqueous medium (C) include water, organic solvents miscible with water, and mixtures thereof. Examples of the organic solvent miscible with water include alcohol solvents such as methanol, ethanol, n-propanol and isopropanol; ketone solvents such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; Alkyl ethers; lactam solvents such as N-methyl-2-pyrrolidone and the like. In the present invention, only water may be used, a mixture of water and an organic solvent miscible with water may be used, or only an organic solvent miscible with water may be used.

  Moreover, as said aqueous medium (C), from the point of safety | security and the load with respect to an environment, only water or a mixture with water and the organic solvent mixed with water is preferable, and only water is especially preferable.

  The ratio of the aqueous medium (C) is preferably in the range of 10 to 90% by mass and more preferably in the range of 30 to 70% by mass in the total amount of the aqueous resin composition.

  In producing the aqueous resin composition of the present invention, the aromatic compound (B) may be added before the urethane resin (A) is dispersed in the aqueous medium (C). The urethane resin (A) may be added after being dispersed in the aqueous medium (C). When the aromatic compound (B) is added after the urethane resin (A) is dispersed in the aqueous medium (C), an emulsifier or the like may be used as necessary.

  Moreover, when the said urethane resin (A) is disperse | distributed in an aqueous medium (C), you may use an emulsifier etc. as needed.

  Examples of the emulsifier include nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene sorbitol tetraoleate, and polyoxyethylene / polyoxypropylene copolymer. Fatty acid salts such as sodium oleate, alkyl sulfate esters, alkylbenzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, polyoxyethylene alkyl sulfates, alkane sulfonate sodium salts, sodium alkyl diphenyl ether sulfonates, etc. And anionic emulsifiers.

  The urethane resin (A) aqueous dispersion obtained by water-dispersing the urethane resin (A) has a polymerization initiator for proceeding radical polymerization of the polymerizable unsaturated group of the urethane resin (A). It is preferable to use it.

  As the polymerization initiator, for example, benzophenone, benzyl, Michler ketone, thioxanthone, anthraquinone, benzoin, dialkoxyacetophenone, acyloxime ester, benzyl ketal, hydroxyalkylphenone, halogenoketone, and the like can be used. The photopolymerization initiator may be used in combination with a tertiary amine such as methylamine, diethanolamine, N-methyldiethanolamine, or tributylamine as necessary.

  Examples of the polymerization initiator include 2,2′-azobis (2-methylpropionamidine) dihydrochloride, 4,4′-azobis (4-cyano) valeric acid, 2,2′-azobis (2- Thermal polymerization initiators such as amidinopropane) dihydrochloride, benzoyl peroxide, t-butyl hydroperoxide, peroxides such as hydrogen peroxide can also be used.

  It is preferable to use the said polymerization initiator in 0.5-5 mass parts with respect to 100 mass parts of solid content of a urethane resin (A).

  The urethane resin (A) aqueous dispersion may contain an additive as necessary. Examples of the additive include a compound having a polymerizable unsaturated group, a film forming aid, a filler, and thixotropy. An imparting agent, a tackifier, a pigment, an antibacterial agent, and the like can be used as long as the object of the present invention is not impaired.

  Examples of the compound having a polymerizable unsaturated group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meta ) Acrylate, 1-adamantyl (meth) acrylate, ethylene glycol di (meth) acrylate, 1,3-propanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate , Pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, ditrimethyl Lumpur propane tetra (meth) acrylate. Of these, dipentaerythritol hexa (meth) acrylate is preferably used. By using these, a urethane resin composition capable of forming a coating film with higher hardness can be obtained.

  Examples of the film forming aid include an anionic surfactant (dioctylsulfosuccinic acid ester soda salt and the like), a hydrophobic nonionic surfactant (such as sorbitan monooleate) and silicone oil.

  Examples of the thixotropy-imparting agent include fatty acid, fatty acid metal salt, fatty acid ester, paraffin, resin acid, surfactant, polyacrylic acid and the like surface-treated filler, polyvinyl chloride powder, hydrogenated castor oil, Fine powder silica, organic bentonite, sepiolite and the like can be mentioned.

  As the pigment, known and commonly used inorganic pigments and organic pigments can be used.

  Examples of the inorganic pigment that can be used include titanium oxide, antimony red, bengara, cadmium red, cadmium yellow, cobalt blue, bitumen, ultramarine, carbon black, and graphite.

  Examples of the organic pigment include quinacridone pigment, quinacridone quinone pigment, dioxazine pigment, phthalocyanine pigment, anthrapyrimidine pigment, ansanthrone pigment, indanthrone pigment, flavanthrone pigment, perylene pigment, diketopyrrolopyrrole pigment, perinone pigment, Organic pigments such as quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, and azo pigments can be used. Two or more kinds of these pigments can be used in combination. These pigments may be surface-treated and have a self-dispersing ability with respect to an aqueous medium.

  As the antibacterial agent, for example, silver chloride, trifluoride, dichlorofluoride, fluorophorpet, zinc pyrithione, methyl 2-benzimidazole carbanate, 2- (4-thiazolyl) benzimidazole and the like can be used.

  Examples of other additives include reaction accelerators (metal reaction accelerators, metal salt reaction accelerators, amine reaction accelerators, etc.), stabilizers (ultraviolet absorbers, antioxidants, heat stabilizers, etc.). , Various additives such as a moisture removing agent (4-paratoluenesulfonyl isocyanate, etc.), an adsorbent (quick lime, slaked lime, zeolite, molecular sieve, etc.), an adhesion-imparting agent, an antifoaming agent, and a leveling agent.

  The aqueous resin composition of the present invention can be suitably used, for example, as a coating agent that can impart surface protection and design properties to various substrates.

  As a base material which can apply | coat the said coating agent and can form a coating film, a glass base material, a metal base material, a plastic base material, paper, a wood base material, a fiber base material etc. are mentioned, for example. Moreover, the base material of porous body structures, such as a urethane foam, can also be used.

  Examples of the plastic substrate include a polycarbonate substrate, a polyester substrate, an acrylonitrile-butadiene-styrene substrate, a polyacryl substrate, a polystyrene substrate, a polyurethane substrate, an epoxy resin substrate, a polyvinyl chloride substrate, and a polyamide group. Material can be used.

  As said metal base material, plated steel plates, such as a galvanized steel plate and an aluminum zinc alloy steel plate, an iron plate, an aluminum plate, an aluminum alloy plate, an electromagnetic steel plate, a copper plate, a stainless steel plate etc. can be used, for example.

  The base material may be a planar material made of the above material or may have a curved portion, or may be a base material made of fibers such as a nonwoven fabric.

  The coating agent of the present invention has, for example, the urethane resin (A) after being applied directly to the surface of the base material or the surface of the base material on which a primer layer or the like has been previously provided and then dried. A coating film can be formed by advancing radical polymerization of a polymerizable unsaturated double group.

  In addition, a coating film is formed on the surface of the release paper by applying the coating agent on the release paper, then drying and curing, and a non-woven fabric obtained by applying an adhesive or an adhesive on the coating film. A film formed using the coating agent can be laminated on the surface of a desired substrate by laminating the substrate made of such fibers and peeling the release paper.

  Examples of the method for applying the coating agent on the substrate include a spray method, a curtain coater method, a flow coater method, a roll coater method, a brush coating method, and a dipping method.

  Examples of the method for curing the coating agent include a heating method and a method of irradiating active energy rays such as ultraviolet rays.

  The heating method varies depending on the type of radical polymerization initiator to be used. For example, by performing the heating at a temperature of about 100 ° C. to 150 ° C. for about 10 minutes to 30 minutes, the radical polymerization is advanced and cured. it can.

  In addition, as a method of irradiating the active energy ray, for example, a method using a known lamp such as a xenon lamp, a xenon-mercury lamp, a metal halide lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, or an LED lamp is used. Can be mentioned.

The exposure dose of the actinic energy ray is preferably in the range of 0.05~5J / cm ^2, more preferably in the range of ^{0.1~3J / cm 2, 0.1~1J / cm} 2 It is particularly preferable that the range is In addition, said ultraviolet irradiation amount is based on the value measured in the wavelength range of 300-390 nm using UV checker UVR-N1 (made by Nippon Battery Co., Ltd.).

  Although the thickness of the coating film that can be formed using the coating agent of the present invention can be appropriately adjusted according to the use of the substrate, it is usually preferably about 0.1 to 100 μm.

  As described above, articles provided with a coating film formed using the coating agent on the substrate are optical members such as liquid crystal displays and flexible displays, mobile phones, various plastic products including home appliances, It can be used as metal products such as automobile exteriors and building materials.

  Hereinafter, the present invention will be specifically described by way of examples and comparative examples.

(Example 1: Synthesis of aqueous resin composition (1))
In a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 102.4 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number average molecular weight 2000) 100 parts by mass, 2,2-dimethylolpropionic acid 13.4 parts by mass, 1,6-hexanediol 7.9 parts by mass, pentaerythritol diacrylate (general formula R ^{1 in} (1) has 3 carbon atoms and has 2 atomic groups having a polymerizable unsaturated group.) 35.2 parts by mass, 0.007 parts by mass of methylhydroquinone, and , 0.07 part by mass of 2,6-tert-butyl-p-cresol was charged and adjusted to 50 ° C. while stirring. It was.

  Next, 106.9 parts by mass of dicyclohexylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 73.1 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene was mixed, 10.1 parts by mass of triethylamine was supplied, and 653.5 parts by mass of ion-exchanged water was added dropwise. .

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain an aqueous resin composition having a non-volatile content of 33% by mass. A product (1) was obtained.

(Example 2: Synthesis of aqueous resin composition (2))
To a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 102.4 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number average molecular weight 2000) 100 parts by mass, 2,2-dimethylolpropionic acid 13.4 parts by mass, 1,6-hexanediol 7.9 parts by mass, pentaerythritol diacrylate (general formula R ^{1 in} (1) has 3 carbon atoms and has 2 atomic groups having a polymerizable unsaturated group.) 35.2 parts by mass, 0.007 parts by mass of methylhydroquinone, and , 0.07 part by mass of 2,6-tert-butyl-p-cresol was charged and adjusted to 50 ° C. while stirring. It was.

  Next, 106.9 parts by mass of dicyclohexylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 73.1 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of ethoxylated o-phenylphenol acrylate was mixed, 10.1 parts by mass of triethylamine was supplied, and 653.5 parts by mass of ion-exchanged water was added dropwise.

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain a 33% by mass aqueous resin composition having a non-volatile content. A product (2) was obtained.

(Example 3: Synthesis of aqueous resin composition (3))
To a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 102.4 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number average molecular weight 2000) 100 parts by mass, 2,2-dimethylolpropionic acid 13.4 parts by mass, 1,6-hexanediol 7.9 parts by mass, pentaerythritol diacrylate (general formula R ^{1 in} (1) has 3 carbon atoms and has 2 atomic groups having a polymerizable unsaturated group.) 35.2 parts by mass, 0.007 parts by mass of methylhydroquinone, and , 0.07 part by mass of 2,6-tert-butyl-p-cresol was charged and adjusted to 50 ° C. while stirring. It was.

  Next, 106.9 parts by mass of dicyclohexylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 73.1 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 1,3-bis (vinylbenzylthio) -1-propanol was mixed, 10.1 parts by mass of triethylamine was supplied, and 653.5 parts by mass of ion-exchanged water was added dropwise.

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain an aqueous resin composition having a non-volatile content of 33% by mass. A product (3) was obtained.

(Example 4: Synthesis of aqueous resin composition (4))
Into a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 103.4 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number average molecular weight 2000) 100 parts by mass, 2,2-dimethylolpropionic acid 13.4 parts by mass, 1,6-hexanediol 8.1 parts by mass, pentaerythritol diacrylate (general formula R ^{1 in} (1) has 3 carbon atoms and has 2 atomic groups having a polymerizable unsaturated group.) 34.7 parts by mass, methylhydroquinone 0.007 parts by mass, and , 0.07 part by mass of 2,6-tert-butyl-p-cresol was charged and adjusted to 50 ° C. while stirring. It was.

  Next, 102 parts by mass of diphenylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 73.8 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene was mixed, 10.1 parts by mass of triethylamine was supplied, and 659.8 parts by mass of ion-exchanged water was added dropwise. .

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain a 33% by mass aqueous resin composition having a non-volatile content. A product (4) was obtained.

(Example 5: Synthesis of aqueous resin composition (5))
In a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 107.5 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number-average molecular weight 2000) 100 parts by mass, 1,2-dimethylolpropionic acid 13.4 parts by mass, bisphenol A ethylene oxide adduct (added mole number: 2) 19.0 parts by mass , Pentaerythritol diacrylate (R ¹ in the general formula (1) has 3 carbon atoms and 2 atomic groups having a polymerizable unsaturated group) 37.2 parts by mass, methyl 0.007 parts by mass of hydroquinone and 0.07 parts by mass of 2,6-tert-butyl-p-cresol The portion was charged and adjusted to 50 ° C. with stirring.

  Next, 106.9 parts by mass of dicyclohexylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 76.7 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene was mixed, 10.1 parts by mass of triethylamine was supplied, and 687.5 parts by mass of ion-exchanged water was added dropwise. .

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain a 33% by mass aqueous resin composition having a non-volatile content. A product (5) was obtained.

(Example 6: Synthesis of aqueous resin composition (6))
In a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 105.6 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number-average molecular weight 2000) 100 parts by mass, 1,2-dimethylolpropionic acid 13.4 parts by mass, bisphenol A ethylene oxide adduct (added mole number: 2) 19.6 parts by mass , Pentaerythritol diacrylate (R ¹ in the general formula (1) has 3 carbon atoms and 2 atomic groups having a polymerizable unsaturated group) 36.7 parts by mass, methyl 0.007 parts by mass of hydroquinone and 0.07 parts by mass of 2,6-tert-butyl-p-cresol The portion was charged and adjusted to 50 ° C. with stirring.

  Next, 102 parts by mass of diphenylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 75.4 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene was mixed, 10.1 parts by mass of triethylamine was supplied, and 674.8 parts by mass of ion-exchanged water was added dropwise. .

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain an aqueous resin composition having a non-volatile content of 33% by mass. A product (6) was obtained.

(Example 7: Synthesis of aqueous resin composition (7))
To a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 105.3 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number average molecular weight 2000) 100 parts by mass, 2,2-dimethylolpropionic acid 13.4 parts by mass, 1,6-hexanediol 7.9 parts by mass, pentaerythritol diacrylate (general formula R ^{1 in} (1) has 3 carbon atoms and has 2 atomic groups having a polymerizable unsaturated group.) 36.2 parts by mass, 0.007 parts by mass of methylhydroquinone, and , 0.07 part by mass of 2,6-tert-butyl-p-cresol was charged and adjusted to 50 ° C. while stirring. It was.

  Next, 106.9 parts by mass of dicyclohexylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 75.2 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 100 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene and 100 parts by mass of ethoxylated o-phenylphenol acrylate are mixed, and 10.1 parts by mass of triethylamine is supplied. 673.1 parts by mass of ion-exchanged water was added dropwise.

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain an aqueous resin composition having a non-volatile content of 33% by mass. A product (7) was obtained.

(Example 8: Synthesis of aqueous resin composition (8))
To a 2 liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser, 108.3 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol, 1,5-pentanediol and diethyl carbonate were added. Polycarbonate polyol obtained by reaction, number average molecular weight 2000) 100 parts by mass, 2,2-dimethylolpropionic acid 13.4 parts by mass, ethylene oxide adduct of bisphenol S (added mole number: 2) 21.5 parts by mass , Pentaerythritol diacrylate (R ¹ in the general formula (1) has 3 carbon atoms and 2 atomic groups having a polymerizable unsaturated group) 36.7 parts by mass, methyl 0.007 parts by mass of hydroquinone and 0.07 parts by mass of 2,6-tert-butyl-p-cresol The portion was charged and adjusted to 50 ° C. with stirring.

  Next, 106.9 parts by mass of dicyclohexylmethane diisocyanate was supplied to the four-necked flask and reacted at 80 ° C. for about 5 hours, and then 77.3 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene was mixed, 10.1 parts by mass of triethylamine was supplied, and 692.6 parts by mass of ion-exchanged water was added dropwise. .

  Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain an aqueous resin composition having a non-volatile content of 33% by mass. Product (8) was obtained.

(Example 9: Synthesis of aqueous resin composition (9))
In a 2-liter four-necked flask equipped with a heating device, a stirrer, a thermometer, and a reflux condenser, 1,4-bis (3-acryloyloxy-2-hydroxypropoxy) butane (R ¹ and R in the general formula (2)) ³ has 2 carbon atoms and has one atomic group having a polymerizable unsaturated group, and R ² has 4 carbon atoms.) 35.9 parts by mass, methylhydroquinone 007 parts by mass and 0.07 parts by mass of 2,6-tert-butyl-p-cresol were charged and adjusted at 50 ° C. with stirring.

  Next, after supplying 106.9 parts by mass of dicyclohexylmethane diisocyanate to the four-necked flask and reacting at 80 ° C. for about 3 hours, 103.4 parts by mass of methyl ethyl ketone, polycarbonate polyol (1,6-hexanediol and 1 Polycarbonate polyol obtained by reacting 1,5-pentanediol and diethyl carbonate, number average molecular weight 2000) 100 parts by mass, 13.4 parts by mass of 2,2-dimethylolpropionic acid, and 1,6-hexanediol 9 .9 parts by mass was supplied and reacted at 80 ° C. for about 3 hours, and then 73.8 parts by mass of methyl ethyl ketone was supplied and cooled to 50 ° C. After cooling, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene was mixed, 10.1 parts by mass of triethylamine was supplied, and 660.4 parts by mass of ion-exchanged water was added dropwise. .

Next, 31.5 parts by mass of a 10% by mass piperazine aqueous solution as a chain extender is supplied to the four-necked flask and reacted, and then the solvent is removed under reduced pressure to obtain an aqueous resin composition having a non-volatile content of 33% by mass. A product (9) was obtained.

(Comparative Example 1: Synthesis of aqueous resin composition (C1))
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 100 parts by mass, 10.6 parts by mass of 1,6-hexanediol, 13.4 parts by mass of 2,2-dimethylolpropionic acid and 106.3 parts by mass of dicyclohexylmethane diisocyanate in 98 parts by mass of methyl ethyl ketone The organic solvent solution of the urethane prepolymer which has an isocyanate group at the terminal was obtained by mixing and making it react on the conditions of the temperature of 80 degreeC in the said reaction container.

  Next, an organic solvent solution of the urethane prepolymer, 21.9 parts by mass of 2-hydroxyethyl acrylate, 0.003 parts by mass of methylhydroquinone, and 0.03 parts by mass of 2,6-tert-butyl-p-cresol And an organic solvent solution of a urethane resin having a polymerizable unsaturated bond in the side chain and an isocyanate group at the terminal of the main chain by reacting under a condition of 80 ° C. in the reaction vessel. Got.

  Next, an organic solvent solution of the urethane resin, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene, and 10 parts by mass of dimethylethanolamine are mixed, and then ion-exchanged water. Add 624.6 parts by mass, sufficiently stir, add 31.5 parts by mass of a 10% by mass piperazine aqueous solution to cause chain extension reaction, and distill under reduced pressure to obtain a urethane resin composition having a non-volatile content of 33% by mass (C1 )

(Comparative Example 2: Synthesis of aqueous resin composition (C2))
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 100 parts by mass, 21.2 parts by mass of 1,6-hexanediol, 13.9 parts by mass of 2,2-dimethylolpropionic acid, 106.3 parts by mass of dicyclohexylmethane diisocyanate, 93.8 parts by mass of methyl ethyl ketone The resulting mixture was mixed and reacted at a temperature of 80 ° C. in the reaction vessel to obtain an organic solvent solution of a urethane prepolymer having an isocyanate group at the terminal.

  Next, an organic solvent solution of the urethane prepolymer, 17.5 parts by mass of pentaerythritol triacrylate, 0.003 parts by mass of methylhydroquinone, and 0.03 parts by mass of 2,6-tert-butyl-p-cresol Are mixed and reacted at a temperature of 80 ° C. in the reaction vessel to obtain an organic solvent solution of a urethane resin having a polymerizable unsaturated bond in the side chain and an isocyanate group at the end of the main chain. It was.

  Next, an organic solvent solution of the urethane resin, 200 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene, and 10 parts by mass of dimethylethanolamine were mixed, and then water 641. Add 4 parts by weight, sufficiently stir, add 31.5 parts by weight of 10% by weight aqueous piperazine solution to cause chain elongation reaction, and distill under reduced pressure to obtain a urethane resin composition (C2) having a nonvolatile content of 33% by weight. Obtained.

[Measurement method of refractive index]
The aqueous resin compositions obtained in Examples and Comparative Examples were applied to the surface of a polypropylene substrate so that the film thickness after drying was 100 μm, then dried at room temperature for 24 hours, and then heat treated at 150 ° C. for 5 minutes. A film was formed by performing. By dissolving the obtained film in N, N-dimethylformamide (DMF), a DMF solution of a urethane resin in which the solid content of the urethane resin constituting the film is 10% by mass, and a urethane resin having a mass of 20% by mass. A DMF solution and a DMF solution of urethane resin having a mass of 30% were prepared.

  By measuring the refractive index of the DMF solution of the three types of urethane resins using a digital refractometer RX-5000 (manufactured by Atago Co., Ltd.), and linearly approximating the measured values, the solid content of the urethane resin can be determined. The refractive index when it was 100% was calculated.

[Method for evaluating hardness of coating film]
Each aqueous resin composition obtained in the Examples and Comparative Examples was applied to the surface of the glass substrate so that the film thickness of the coating film was 15 μm. After the coating material is dried at 140 ° C. for 5 minutes, it is applied to the surface of the glass substrate by irradiating 0.5 J / cm ² of ultraviolet rays for one pass using a high pressure mercury lamp (manufactured by GS Yuasa Co., Ltd.). An article with a laminated film was obtained.

  The hardness of the coating film constituting the article was measured by a method based on a JIS test method (JIS K-5600-5-4: 1999) scratch hardness (pencil method).

[Evaluation method of film elongation]
Obtained by blending 4 parts by mass of a photopolymerization initiator (mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin composition obtained in Examples and Comparative Examples described later Each of the blended solutions was applied to the surface of the release film so that the film thickness of the coating film was 50 μm. The coated material is dried for 24 hours in an environment of 25 ° C., and then, using a high-pressure mercury lamp (manufactured by GS Yuasa Co., Ltd.), one pass of 0.5 J / cm ² of ultraviolet rays is irradiated to remove the release film. Thus, a test film (length 40 mm, width 5 mm) made of the aqueous resin composition was produced.

  The elongation of the test film is measured by using “Autograph AG-Xplus 1 kN (between chucks; 50 mm, tensile speed 50 mm / min)” manufactured by Shimadzu Corporation, and based on the elongation percentage of the test film before the tensile test. Evaluation was performed according to the following evaluation criteria.

A: The length of the test film after the tensile test was increased by 100% or more with respect to the length of the test film before the tensile test.
○: The length of the test film after the tensile test was extended by 50% or more and less than 100% with respect to the length of the test film before the tensile test.
(Circle) (triangle | delta): With respect to the length of the test film before a tensile test, the length of the test film after a tensile test was extended in the range of 30% or more and less than 50%.
(Triangle | delta): The length of the test film after a tensile test extended | stretched in 10% or more and less than 30% with respect to the length of the test film before a tensile test.
X: The length of the test film after the tensile test was elongated within a range of less than 10% with respect to the length of the test film before the tensile test.

[Method for evaluating flexibility of coating film]
Each aqueous resin composition obtained in Examples and Comparative Examples was applied to the surface of a metal plate (untreated steel plate, thickness 0.8 mm) so that the film thickness of the coating film was 2 μm. After drying the coated material at 100 ° C. for 30 seconds, using a high-pressure mercury lamp (manufactured by GS Yuasa Co., Ltd.), one pass irradiation of 0.5 J / cm ² of ultraviolet light is performed to remove the release film, An article having a coating film laminated on the surface of the metal plate was obtained.

  The bendability of the coating film constituting the article is measured by a method based on the JIS test method (JIS K-5600-5-1: 1999) bend resistance test method (mandrel diameter 2 mm), and the measurement result is also shown. In addition, the evaluation was made according to the following evaluation criteria.

○: Cracks, wrinkles and whitening of the coating film were not observed at the bent part of the coating film.
Δ: Some cracks in the coating film or white wrinkles were observed at the bent portion of the coating film.
X: Remarkable cracks of the coating film were observed in the entire bent part of the coating film.

[Method for evaluating solvent resistance of coating film]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The liquid was applied onto a glass substrate using a 3 mil applicator, dried at 60 ° C. for 10 minutes, further irradiated with 0.5 J / cm ² using a high pressure mercury lamp, and then cured at 25 ° C. for 2 days. Was made. The surface of the obtained coating film was rubbed back and forth on the cured coating film 20 times with a felt soaked with methyl ethyl ketone and ethanol. The state of the coating film before rubbing and after rubbing was judged by finger touch and visual observation. The evaluation criteria are as follows.

○: Softening and gloss reduction are not recognized.
(Triangle | delta): Some softening or gloss reduction is recognized.
X: Significant softening or gloss reduction is observed.

[Adhesion to substrate (primary adhesion)]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The solution was applied on each substrate shown below using a 3 mil applicator, dried at 60 ° C. for 30 minutes, further irradiated with 0.5 J / cm ² using a high pressure mercury lamp, and then at 25 ° C. for 2 days. A cured coating was prepared. On the surface of the obtained coating film, a cellophane (registered trademark) peel test of 100 square 1 mm squares was carried out according to JIS K-5400. The number of grids not peeled was measured and evaluated according to the following criteria. As the substrate, a substrate made of polyethylene terephthalate resin and a glass substrate were used.

A: The number of grids not peeled is 90 or more.
○: The number of grids not peeled is 60 or more and less than 90.
(Triangle | delta): The number of grids which do not peel is 40 or more and less than 60.
X: The number of grids which do not peel is less than 40.

  Table 1 shows the compositions of the aqueous resin compositions (1) to (9) obtained in Examples 1 to 9 and the evaluation results. In addition, the composition (blending amount) in the table is expressed as a nonvolatile content.

  Table 2 shows the compositions and evaluation results of the aqueous resin compositions (C1) and (C2) obtained in Comparative Examples 1 and 2. In addition, the composition (blending amount) in Table 2 is expressed as a nonvolatile content.

  From the evaluation results of Examples 1 to 9 shown in Table 1, the coating film obtained using the aqueous resin composition of the present invention has a high refractive index, hardness, elongation, flexibility, and resistance. It was confirmed that the solvent property and the adhesion to the substrate were excellent.

  On the other hand, Comparative Examples 1 and 2 are examples in which a polyol other than the polyol defined in the present invention was used as a polyol that is a raw material of a urethane resin. Although the coating film obtained using the aqueous resin composition of Comparative Examples 1 and 2 had a high refractive index, it was confirmed that the hardness and solvent resistance were insufficient.

Claims (7)

An alkylene diol (a1-1) having two or more polymerizable unsaturated groups represented by the following general formula (1) or an oxyalkylene having two or more polymerizable unsaturated groups represented by the following general formula (2) Urethane resin (A) having a polymerizable unsaturated group obtained by reacting polyol (a1) containing diol (a1-2) with polyisocyanate (a2), aromatic compound (B), and aqueous medium ( C) ,
The aqueous resin composition, wherein an aromatic ring concentration in a nonvolatile content of the aqueous resin composition is in a range of 0.5 to 15 mol / kg .

(R ¹ in the general formula (1) represents a structure having two or more atomic groups containing a polymerizable unsaturated group in the side chain of a linear alkylene group having 1 to 9 carbon atoms.)

(R ¹ and R ³ in the general formula (2) represent a structure having a total of two or more atomic groups containing a polymerizable unsaturated group in the side chain of the ethylene group. R ² has 1 to 5 carbon atoms. Represents an alkylene group.)   The aqueous resin composition according to claim 1, wherein the alkylene diol (a1-1) is pentaerythritol diacrylate.   The total mass of the said alkylene diol (a1-1) and the said oxyalkylene diol (a1-2) is the range of 0.1-49 mass% in the whole quantity of the raw material used for manufacture of the said urethane resin (A). The aqueous resin composition according to claim 1.   The aqueous resin composition according to claim 1, wherein the polyol (a1) further contains a polyester polyol, a polyether polyol or a polycarbonate polyol. The aqueous resin composition according to claim 1, wherein the aromatic compound has a vinyl group or a (meth) acryloyl group .   A coating agent comprising the aqueous resin composition according to any one of claims 1 to 5.   An optical film comprising the coating film of the coating agent according to claim 6.