Urethane (meth) acrylate compound and method for producing same, neutralized product, aqueous resin composition, aqueous active energy ray-curable composition and use thereof, cured product, substrate with cured film, substrate with soft coat layer, and laminate having adhesive layer

Abstract

A urethane (meth) acrylate compound which is obtained by reacting a carboxyl group-containing epoxy (meth) acrylate compound (C), a polyol compound (D), and a polyisocyanate compound (E), the carboxyl group-containing epoxy (meth) acrylate compound (C) is obtained by reacting an epoxy (meth) acrylate compound (A) and an acid anhydride (B), and the urethane (meth) acrylate compound has one or more urethane bonds, one or more (meth) acryloyl groups, and one or more carboxyl groups in the molecule. And at least one carboxyl group is present in a molecular chain that is branched from a molecular chain derived from the epoxy (meth) acrylate compound (A) and does not contain a urethane bond.

Description

Technical Field

[0001] The present invention relates to a carbamate (meth) acrylate compound, a neutralized product of the carbamate (meth) acrylate compound, an aqueous resin composition comprising the neutralized product, an aqueous active energy ray-curable composition comprising the aqueous resin composition, a cured product of the aqueous active energy ray-curable composition, a substrate with a cured film (having the cured product), a soft coating formed by the aqueous active energy ray-curable composition, an adhesive, a sealant, an ink or a resist, a substrate with a soft coating (having the cured product), and a laminate having the cured product. This application claims priority based on Japanese Patent Application No. 2023-054677 filed in Japan on March 30, 2023, and its contents are incorporated herein by reference. Background Art

[0002] Conventionally, methods known for producing aqueous urethane acrylates include methods using surfactants, self-emulsifying methods using hydrophilic polyols (e.g., polyethylene glycol) as the polyol constituting the urethane acrylate, and methods of introducing hydrophilic groups (e.g., carboxyl groups, sulfonic acid groups, tertiary amino groups, etc.) into the urethane acrylate.

[0003] As a method for introducing a hydrophilic group into urethane acrylate, the introduction of a carboxyl group is the easiest and most commonly used method.

[0004] Patent Document 1 proposes a photocurable resin composition containing a urethane acrylate as a composition that can be diluted with water or an alcoholic solvent. The urethane acrylate is obtained by subjecting a hydroxyl group-containing urethane compound to a urethanization reaction with an acrylate compound containing a terminal isocyanate group on one side. The hydroxyl group-containing urethane compound is obtained by reacting a diisocyanate compound, a carboxyl group-containing diol compound, a triol compound, a terminal hydroxyl group-containing diol compound, and a hydroxyl group-containing unsaturated compound.

[0005] Patent Document 2 proposes a carbamate polymer aqueous dispersion and an active energy ray-curable aqueous resin composition containing the same. The carbamate polymer aqueous dispersion is prepared by adding a tertiary amine to a carbamate (meth)acrylate prepolymer obtained by subjecting a carboxyl-free polyol, a carboxyl-containing polyol, an organic isocyanate, and a hydroxyl-containing multifunctional (meth)acrylate to a urethanization reaction, neutralizing the prepolymer, and then ureidating the neutralized product by adding water.

[0006] Patent Document 3 proposes a method in which, by using a dihydroxycarboxylic acid as an initiator when synthesizing polycaprolactone polyol, one carboxyl group can be reliably introduced into one polycaprolactone polyol and the carboxyl groups in the urethane acrylate resin can be arbitrarily adjusted.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent No. 3911792

[0010] Patent Document 2: Japanese Patent Application Laid-Open No. 2004-168809

[0011] Patent Document 3: Japanese Patent Application Laid-Open No. 7-157531 Summary of the Invention

[0012] Technical problem to be solved by the invention

[0013] The urethane bond portion of urethane acrylate has high cohesive strength and easily forms a hard segment.

[0014] As shown in Patent Documents 1 and 2, in the method of introducing carboxyl groups using dihydroxycarboxylic acid as a chain extender, the site derived from the chain extender is contained in the hard segment, and therefore the effect of improving water solubility or water dispersibility by the introduction of carboxyl groups cannot be fully achieved.

[0015] Therefore, although water solubility or water dispersibility can be improved by increasing the amount of the carboxyl group-containing chain extender used, there is a disadvantage that the ratio of the hard segment increases, making it very difficult to achieve the required balance of physical properties.

[0016] Furthermore, as shown in Patent Document 3, the disadvantages of Patent Documents 1 and 2 can be improved by using dihydroxycarboxylic acids in the ring-opening of lactones. However, this is difficult to apply to polyols other than lactone-based polyols. Furthermore, the introduction of carboxyl groups as pendant groups from the molecular chain of the initiator results in poor water dispersibility and dispersion stability.

[0017] An object of the present invention is to provide a novel urethane (meth)acrylate compound capable of improving water dispersibility.

[0018] Another object of the present invention is to provide an aqueous active energy ray-curable composition capable of improving the flexibility of a cured product.

[0019] Solutions to Problems

[0020] The present invention has the following aspects.

[0021] [1] A urethane (meth)acrylate compound, the urethane (meth)acrylate compound being obtained by reacting a carboxyl group-containing epoxy (meth)acrylate compound (C), a polyol compound (D), and a polyisocyanate compound (E), wherein the carboxyl group-containing epoxy (meth)acrylate compound (C) is obtained by reacting an epoxy (meth)acrylate compound (A) and an acid anhydride (B), wherein the urethane (meth)acrylate compound has one or more urethane bonds, one or more (meth)acryloyl groups, and one or more carboxyl groups in one molecule, and at least one carboxyl group is present in a molecular chain branched from a molecular chain derived from the epoxy (meth)acrylate compound (A) and not containing a urethane bond.

[0022] [2] The urethane (meth)acrylate compound according to [1], wherein the double bond equivalent is 100 to 10,000.

[0023] [3] The urethane (meth)acrylate compound according to [1] or [2], wherein the acid value is 10 KOHmg / g to 500 KOHmg / g.

[0024] [4] The urethane (meth)acrylate compound according to any one of [1] to [3], wherein the content of the urethane bond is 1% by mass to 50% by mass relative to the total mass of the urethane (meth)acrylate compound.

[0025] [5] The urethane (meth)acrylate compound according to any one of [1] to [4], wherein the epoxy (meth)acrylate compound (A) is at least one selected from aliphatic epoxy (meth)acrylates, alicyclic epoxy (meth)acrylates, and aromatic epoxy (meth)acrylates.

[0026] [6] The urethane (meth)acrylate compound according to any one of [1] to [5], wherein the acid anhydride (B) is at least one selected from aliphatic acid anhydrides, alicyclic acid anhydrides, and aromatic acid anhydrides.

[0027] [7] The urethane (meth)acrylate compound according to any one of [1] to [6], wherein the polyol compound (D) is at least one selected from polyether polyol, polycarbonate polyol, and polyester polyol.

[0028] [8] The urethane (meth)acrylate compound according to any one of [1] to [7], wherein the polyisocyanate compound (E) is at least one selected from aliphatic polyisocyanates, alicyclic polyisocyanates, and aromatic polyisocyanates.

[0029] [9] A neutralized product obtained by neutralizing the urethane (meth)acrylate compound according to any one of [1] to [8] with an amine compound.

[0030]

[10] An aqueous resin composition, which is obtained by dispersing the neutralized product described in [9] above in water.

[0031]

[11] The aqueous resin composition according to

[10] , wherein the average particle size is 10 nm to 200 nm.

[0032]

[12] An aqueous active energy ray-curable composition comprising the aqueous resin composition described in

[10] or

[11] above and a photopolymerization initiator.

[0033]

[13] A cured product of the aqueous active energy ray-curable composition according to

[12] .

[0034]

[14] The cured product according to

[13] , wherein the Shore D hardness is 45 or less.

[0035]

[15] A substrate with a cured coating, wherein the substrate has a cured coating formed from the cured product according to

[13] or

[14] on its surface.

[0036]

[16] A soft coating agent, an adhesive, a sealant, an ink, or a resist, which is formed from the aqueous active energy ray-curable composition according to

[12] .

[0037]

[17] A substrate with a soft coating, wherein the substrate has a soft coating layer formed from the cured product according to

[13] or

[14] on its surface.

[0038]

[18] A laminate comprising an adhesive layer formed from the cured product according to

[13] or

[14] between a substrate and an adherend.

[0039]

[19] A method for producing a urethane (meth)acrylate compound, comprising:

[0040] a step of reacting the epoxy (meth)acrylate compound (A) and the acid anhydride (B) to obtain a carboxyl group-containing epoxy (meth)acrylate compound (C); and

[0041] A step of reacting the obtained carboxyl group-containing epoxy (meth)acrylate compound (C), the polyol compound (D), and the polyisocyanate compound (E).

[0042] Effects of the Invention

[0043] According to the present invention, a urethane (meth)acrylate compound capable of improving water dispersibility can be obtained. According to the present invention, an aqueous active energy ray-curable composition capable of improving the flexibility of a cured product can be obtained. DETAILED DESCRIPTION

[0044] The following definitions of terms apply throughout this specification and claims.

[0045] "(Meth)acrylate" is a compound having one or more (meth)acryloyl groups.

[0046] "(Meth)acryloyl" is a general term for acryloyl and methacryloyl.

[0047] "(Meth)acrylic acid" is a general term for acrylic acid and methacrylic acid.

[0048] The “weight average molecular weight” (hereinafter also referred to as “Mw”) is a value in terms of standard polystyrene measured by gel permeation chromatography (hereinafter also referred to as “GPC”).

[0049] The "hydroxyl value" is the amount of potassium hydroxide required to acetylate the hydroxyl groups in a sample and neutralize the acetic acid used in the acetylation, expressed in mg per 1.0 g of the sample. It serves as a standard for indicating the hydroxyl content in a sample. The hydroxyl value is measured using the neutralization titration method specified in JIS K 0070:1992.

[0050] The "double bond equivalent" of the urethane (meth)acrylate compound refers to the mass per 1 mol of double bonds in the urethane (meth)acrylate compound, and the unit can be expressed in g / mol.

[0051] The "acid value" of a urethane (meth)acrylate compound is the mass of potassium hydroxide required to neutralize the acid contained in 1 g of the urethane (meth)acrylate compound. For example, the acid value is calculated by diluting the urethane (meth)acrylate compound with acetone and titrating with a 0.1N potassium hydroxide-methanol solution using phenolphthalein as an indicator. The measured value is converted to the amount per 1 g of the urethane (meth)acrylate compound.

[0052] The average particle size of the aqueous resin composition is determined by measuring the particle size distribution of a measurement sample (25° C.) obtained by diluting the aqueous resin composition with water to a solid content concentration of 1% to 2% by mass by dynamic light scattering, and taking the volume-based median diameter as the average particle size.

[0053] Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0054] Urethane (meth)acrylate compounds

[0055] The urethane (meth)acrylate compound of the present invention (hereinafter also referred to as "compound (a)") is a compound obtained by reacting the following components (A) and (B) with components (C), (D), and (E).

[0056] Component (A): Epoxy (meth)acrylate compound (A)

[0057] (B) Component: Acid anhydride (B)

[0058] Component (C): Carboxyl-containing epoxy (meth)acrylate compound (C)

[0059] Component (D): Polyol compound (D)

[0060] Component (E): Polyisocyanate compound (E)

[0061] The compound (a) has one or more urethane bonds, one or more (meth)acryloyl groups, and one or more carboxyl groups in one molecule.

[0062] At least one carboxyl group of the compound (a) is present in a molecular chain branched from a molecular chain derived from the epoxy (meth)acrylate compound (A) and containing no urethane bond.

[0063] The carboxyl group present in the molecular chain (which is branched from the molecular chain derived from the epoxy (meth)acrylate compound (A) and does not contain a urethane bond) contributes to improving water dispersibility.

[0064] Preferably, at least one carboxyl group of the compound (a) is present at a terminal of the molecular chain branched from the molecular chain derived from the epoxy (meth)acrylate compound (A) and containing no urethane bond.

[0065] The compound (a) has a double bond derived from a (meth)acryloyl group.

[0066] The double bond equivalent of compound (a) is preferably 100 to 10,000, more preferably 100 to 5,000, and even more preferably 100 to 1,000.

[0067] When the number of moles of component (A) required to produce 1 g of compound (a) is α mol and the number of radically polymerizable double bonds contained in one molecule of component (A) is β, the double bond equivalent of compound (a) is calculated as 1 / (α×β).

[0068] When the double bond equivalent of the compound (a) is at least the lower limit of the above range, the flexibility is excellent, and when it is at most the upper limit, the curability, abrasion resistance, and chemical resistance are excellent.

[0069] The acid value of the compound (a) is preferably 10 KOH mg / g to 500 KOH mg / g, more preferably 10 KOH mg / g to 100 KOH mg / g, and even more preferably 10 KOH mg / g to 50 KOH mg / g.

[0070] When the acid value of the compound (a) is at least the lower limit of the above range, the compound has excellent water dispersibility, and when it is at most the upper limit, the compound has excellent flexibility.

[0071] The content of the urethane bond (—NHCOO—) in the compound (a) (hereinafter also referred to as “urethane bond concentration”) is preferably 1% by mass to 50% by mass, more preferably 3% by mass to 25% by mass, and even more preferably 5% by mass to 15% by mass relative to the total mass of the urethane (meth)acrylate.

[0072] When the urethane bond content is at least the lower limit of the above range, the curability, abrasion resistance, and chemical resistance are excellent, while when it is at most the upper limit, the flexibility is excellent.

[0073] <(A)Component>

[0074] The epoxy (meth)acrylate compound (A) is a compound obtained by a condensation reaction between an epoxy group of an epoxy compound having an epoxy group and a carboxyl group of (meth)acrylic acid.

[0075] (A) Component has a (meth)acryloyl group derived from (meth)acrylic acid and a hydroxyl group derived from an epoxy group.

[0076] The number of epoxy groups present in one molecule of the epoxy compound is preferably 2 to 6, more preferably 2 to 4, and even more preferably 2 to 3.

[0077] The number of (meth)acryloyl groups present in one molecule of the component (A) is preferably 2 to 6, more preferably 2 to 4, and even more preferably 2 to 3.

[0078] The number of hydroxyl groups present in one molecule of the component (A) is preferably 2 to 6, more preferably 2 to 4, and even more preferably 2 to 3.

[0079] As the component (A), at least one selected from the group consisting of aliphatic epoxy (meth)acrylates, alicyclic epoxy (meth)acrylates, and aromatic epoxy (meth)acrylates is preferred.

[0080] Examples of aliphatic epoxy (meth)acrylates include ethylene glycol diglycidyl ether (meth)acrylate adducts, propylene glycol diglycidyl ether (meth)acrylate adducts, 1,4-butanediol diglycidyl ether (meth)acrylate adducts, 1,5-pentanediol diglycidyl ether (meth)acrylate adducts, 1,6-hexanediol diglycidyl ether (meth)acrylate adducts, 1,7-heptanediol diglycidyl ether (meth)acrylate adducts, 1,8-octanediol diglycidyl ether (meth)acrylate adducts, and neopentyl glycol diglycidyl ether (meth)acrylate adducts. Acrylic acid adducts, diethylene glycol diglycidyl ether (meth)acrylic acid adducts, tripropylene glycol diglycidyl ether (meth)acrylic acid adducts, polyethylene glycol diglycidyl ether (meth)acrylic acid adducts, polypropylene glycol diglycidyl ether (meth)acrylic acid adducts, glycerol triglycidyl ether (meth)acrylic acid adducts, trimethylolpropane triglycidyl ether (meth)acrylic acid adducts, sorbitol tetraglycidyl ether (meth)acrylic acid adducts, dipentaerythritol hexaglycidyl ether (meth)acrylic acid adducts, polyglycerol polyglycidyl ether (meth)acrylic acid adducts, and the like.

[0081] Examples of the alicyclic epoxy (meth)acrylate include hydrogenated bisphenol A diglycidyl ether (meth)acrylate adduct, hydrogenated bisphenol F diglycidyl ether (meth)acrylate adduct, 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (meth)acrylate adduct, bis(3,4-epoxycyclohexylmethyl)adipate (meth)acrylate adduct, 4-vinylcyclohexene dioxide (meth)acrylate adduct, hexahydrophthalic acid diglycidyl ether (meth)acrylate adduct, hexahydroterephthalic acid diglycidyl ether (meth)acrylate adduct, and 2,2-bis(hydroxymethyl)-1-butanol 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct (meth)acrylate adduct.

[0082] Examples of aromatic epoxy (meth)acrylates include bisphenol A diglycidyl ether (meth)acrylate adducts, bisphenol F diglycidyl ether (meth)acrylate adducts, bisphenol S diglycidyl ether (meth)acrylate adducts, 4,4'-bisphenol diglycidyl ether (meth)acrylate adducts, tetramethylbisphenol A diglycidyl ether (meth)acrylate adducts, dimethylbisphenol A diglycidyl ether (meth)acrylate adducts, tetramethylbisphenol F diglycidyl ether (meth)acrylate adducts, dimethylbisphenol F diglycidyl ether (meth)acrylate adducts, tetramethylbisphenol S diglycidyl ether (meth)acrylate adducts, dimethylbisphenol S diglycidyl ether (meth)acrylate adducts, biphenyl diglycidyl ether (meth)acrylate adducts, tetramethylbiphenyl tetramethyl-4,4'-bisphenol diglycidyl ether (meth)acrylate adducts, and diphenyl ether. Methyl-4,4'-bisphenol diglycidyl ether (meth) acrylic acid adduct, 1-(4-hydroxyphenyl)-2-[4-(1,1-bis-(4-hydroxyphenyl)ethyl)phenyl]propane diglycidyl ether (meth) acrylic acid adduct, 2,2'-methylenebis(4-methyl-6-tert-butylphenol) diglycidyl ether (meth) acrylic acid adduct, 4,4'-butylene-bis(3-methyl-6-tert-butylphenol) diglycidyl ether (meth) acrylic acid adduct Water glyceryl ether (meth)acrylate adduct, trihydroxyphenylmethane diglycidyl ether (meth)acrylate adduct, resorcinol diglycidyl ether (meth)acrylate adduct, hydroquinone diglycidyl ether (meth)acrylate adduct, 1,1-di-4-hydroxyphenylfluorene diglycidyl ether (meth)acrylate adduct, novolac type epoxy resin (meth)acrylate adduct, bisphenol type epoxy resin (meth)acrylate adduct, etc.

[0083] The component (A) is preferably selected according to the properties of the compound (a) to be obtained.

[0084] For example, in terms of yellowing suppression and flexibility, aliphatic epoxy (meth)acrylate is preferred, and 1,6-hexanediol diglycidyl ether acrylic acid adduct is more preferred.

[0085] For example, in terms of yellowing suppression and toughness, alicyclic epoxy (meth)acrylate is preferred, and hydrogenated bisphenol A diglycidyl ether acrylic acid adduct is more preferred.

[0086] For example, in terms of abrasion resistance and chemical resistance, aromatic epoxy (meth)acrylates are preferred, and bisphenol A diglycidyl ether acrylic acid adduct is more preferred.

[0087] The molecular weight of component (A) is preferably 100 to 10,000, more preferably 100 to 5,000, and even more preferably 100 to 1,000. Component (A) having a molecular weight of at least the lower limit of the above range exhibits excellent flexibility, while having a molecular weight of at most the upper limit exhibits excellent toughness.

[0088] <(B) Component>

[0089] The acid anhydride (B) is a compound formed by dehydration condensation of two molecules of carboxylic acid, or a compound formed by intramolecular dehydration of two carboxyl groups present in one molecule.

[0090] The number of the acid anhydride group (—C(═O)—OC(═O)—) present in one molecule of the acid anhydride (B) may be one or two or more, but preferably one.

[0091] The acid anhydride (B) is preferably at least one selected from aliphatic acid anhydrides, alicyclic acid anhydrides, and aromatic acid anhydrides.

[0092] Examples of the aliphatic acid anhydride include succinic anhydride, fumaric anhydride, maleic anhydride, dodecenylsuccinic anhydride, itaconic anhydride, and citraconic anhydride.

[0093] Examples of the alicyclic acid anhydride include hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0094] Examples of the aromatic acid anhydride include phthalic anhydride, 3-methylphthalic anhydride, trimellitic anhydride, and pyromellitic anhydride.

[0095] The component (B) is preferably selected according to the properties of the compound (a) to be obtained.

[0096] For example, in terms of yellowing suppression and flexibility, aliphatic acid anhydrides are preferred, and succinic anhydride is more preferred.

[0097] For example, in terms of yellowing inhibition and toughness, alicyclic acid anhydrides are preferred, and hexahydrophthalic anhydride is more preferred.

[0098] For example, in terms of abrasion resistance and chemical resistance, aromatic anhydrides are preferred, and phthalic anhydride is more preferred.

[0099] <(C) Component>

[0100] The carboxyl group-containing epoxy (meth)acrylate compound (C) is a compound in which a carboxyl group is introduced into component (A) by the reaction between component (A) and component (B). Hydroxyl groups derived from component (A) remain in component (C).

[0101] The reaction mechanism of the components (A) and (B) will be described later.

[0102] <(D) Component>

[0103] The average number of hydroxyl groups per molecule of the polyol compound (D) is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 to 2.5.

[0104] As the component (D), two or more compounds having different average hydroxyl number may be used in combination.

[0105] The component (D) contains at least a polyhydric alcohol and may further contain a monohydric alcohol.

[0106] The polyol is preferably at least one selected from polyether polyol, polycarbonate polyol, and polyester polyol.

[0107] The monool is preferably at least one selected from polyether monool, polycarbonate monool, and polyester monool.

[0108] The total content of the polyol is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, and may be 100% by mass, relative to the total mass of the component (D).

[0109] Examples of the polyether polyol include polyoxyalkylene polyol.

[0110] As the polyoxyalkylene polyol, for example, one obtained by subjecting a cyclic ether to ring-opening addition polymerization in an initiator can be used.

[0111] As the initiator, a hydroxyl group-containing compound is preferred, preferably a monohydric alcohol and / or a polyhydric alcohol. A mixture of a monohydric alcohol and a polyhydric alcohol and / or a mixture of polyhydric alcohols having different numbers of hydroxyl groups can also be used as the initiator.

[0112] As the cyclic ether, alkylene oxide and / or tetrahydrofuran are preferred.

[0113] The number of active hydrogen atoms of the cyclic ether in the initiator (for example, the number of hydrogen atoms of the hydroxyl group) that reacts becomes the number of hydroxyl groups of the obtained polyoxyalkylene polyol.

[0114] Specific examples of the polyoxyalkylene polyol include polyoxyethylene polyol, polyoxypropylene polyol, poly(oxyethylene-oxypropylene) polyol, and polyoxytetramethylene polyol.

[0115] The polyoxyalkylene polyols may be used alone or in combination of two or more.

[0116] Examples of the polycarbonate polyol include reaction products of carbonate and diol.

[0117] Specific examples of the carbonate include diaryl carbonates such as diphenyl carbonate and dialkyl carbonates such as dimethyl carbonate and diethyl carbonate.

[0118] Examples of the diol include low molecular weight diols. Examples of low molecular weight diols include diols having a molecular weight of about 60 to 300, and specific examples include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, butanediol, 1,6-hexanediol, 2-methyl-1,8-octanediol, nonanediol, cyclohexanedimethanol, neopentyl glycol, and 3-methyl-1,5-pentanediol.

[0119] The polycarbonate polyols may be used alone or in combination of two or more.

[0120] Examples of the polyester polyol include a reaction product of at least one selected from the above-mentioned low-molecular-weight diols and an acid component consisting of at least one dicarboxylic acid and / or a reactive derivative thereof.

[0121] Examples of the acid component include dibasic acids such as adipic acid, sebacic acid, succinic acid, maleic acid, phthalic acid, hexahydrophthalic acid, and terephthalic acid, and their anhydrides.

[0122] Furthermore, polyester polyols obtained by using a trifunctional or higher-functional polycarboxylic acid and / or a reactive derivative thereof as part of the acid component and having an average number of hydroxyl groups exceeding 2 per molecule can also be used.

[0123] Furthermore, polyester polyols having an average hydroxyl group number of 1.8 to 4 per molecule and obtained by ring-opening addition polymerization of cyclic esters in an initiator such as the above-mentioned polyols can also be used. Examples of the cyclic esters include ε-caprolactone.

[0124] The polyester polyols may be used alone or in combination of two or more.

[0125] The weight average molecular weight (Mw) of the component (D) is preferably 200 or more and 15,000 or less, more preferably 300 or more and 10,000 or less, and even more preferably 400 or more and 5,000 or less.

[0126] When the weight average molecular weight of the component (D) is at least the lower limit of the above range, the flexibility is excellent, and when it is at most the upper limit, the curability and / or abrasion resistance and chemical resistance are excellent.

[0127] The hydroxyl value of the component (D) is preferably 30 mgKOH / g to 500 mgKOH / g, more preferably 40 mgKOH / g to 400 mgKOH / g, and preferably 45 mgKOH / g to 300 mgKOH / g.

[0128] When the hydroxyl value of the component (D) is at least the lower limit of the above range, the curability and / or abrasion resistance and chemical resistance are excellent, and when it is at most the upper limit, the flexibility is excellent.

[0129] <(E) Component>

[0130] The polyisocyanate compound (E) is a compound having two or more isocyanate groups (—N═C═O) in one molecule.

[0131] The number of isocyanate groups present in one molecule of the component (E) is preferably 2 to 6, more preferably 2 to 4, and even more preferably 2 to 3.

[0132] The component (E) is preferably at least one selected from aliphatic polyisocyanates, alicyclic polyisocyanates, and aromatic polyisocyanates.

[0133] Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, methylene diisocyanate, ethylene diisocyanate, butylene diisocyanate, propylene diisocyanate, octadecylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, and 1,10-decamethylene diisocyanate.

[0134] Examples of alicyclic polyisocyanates include alicyclic diisocyanates such as 4,4′-methylenebis(cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2,6)-diisocyanate, 1,3-(isocyanatomethyl)cyclohexane, isophorone diisocyanate, dimer acid diisocyanate, 1,3-cyclohexylene diisocyanate, and 4,4′-methylene-bis(cyclohexyl isocyanate).

[0135] Examples of aromatic polyisocyanates include toluene diisocyanate (also known as toluene diisocyanate), 4,4'-diphenylmethane diisocyanate, xylylenediisocyanate, xylene diisocyanate, dianisidine diisocyanate, phenyl diisocyanate, halogenated phenyl diisocyanate, 1,5-naphthalene diisocyanate, polymethylene polyphenylene diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, 3-phenyl-2-ethylene diisocyanate, isopropylbenzene-2,4-diisocyanate, 4-methoxy-1,3-phenylene diisocyanate, 4-ethoxy-1,3-phenylene diisocyanate, 2,4'-diisocyanate diphenyl ether, 5,6-dimethyl-1,3-phenylene diisocyanate, 4,4'- Aromatic diisocyanates such as diphenyl ether diisocyanate, benzidine diisocyanate, 9,10-anthracene diisocyanate, 4,4'-benzyl diisocyanate, 3,3'-dimethyl-4,4'-diisocyanate diphenylmethane, 2,6-dimethyl-4,4'-diisocyanatodiphenyl, 3,3'-dimethoxy-4,4'-diisocyanatodiphenyl, 1,4-anthracene diisocyanate, and phenylene diisocyanate.

[0136] The component (E) is preferably selected according to the desired properties of the compound (a).

[0137] For example, in terms of yellowing suppression and flexibility, aliphatic polyisocyanates are preferred, and hexamethylene diisocyanate and trimethylhexamethylene diisocyanate are more preferred.

[0138] For example, in terms of yellowing inhibition and toughness, alicyclic polyisocyanates are preferred, and isophorone diisocyanate, 4,4′-methylenebis(cyclohexyl isocyanate), and 1,3-(isocyanatomethyl)cyclohexane are more preferred.

[0139] For example, in terms of abrasion resistance and chemical resistance, aromatic polyisocyanates are preferred, and toluene diisocyanate, 4,4′-diphenylmethane diisocyanate, and xylylene diisocyanate are more preferred.

[0140] The polyisocyanate compound (E) may be any of a biuret form, a urate form, an adduct form, and an allophanate form.

[0141] <<Method for producing urethane (meth)acrylate compound>>

[0142] Compound (a) can be produced by a method comprising the following first and second steps.

[0143] First step: a step of reacting component (A) and component (B) to obtain component (C).

[0144] Step 2: A step of reacting the components (C), (D), and (E) to obtain the compound (a).

[0145] <Step 1>

[0146] In the first step, the acid anhydride group (—C(═O)—OC(═O)—) in the component (B) undergoes a ring-opening addition reaction with the hydroxyl group in the component (A) to produce the component (C).

[0147] The acid anhydride undergoes ring-opening addition to some of the hydroxyl groups in component (A) to form a branched chain having a carboxyl group. Specifically, a structure is obtained in which a carboxyl group exists on a molecular chain branching from the molecular chain derived from component (A) and not containing a urethane bond.

[0148] When the number of acid anhydride groups in component (B) is one, component (B) undergoes ring-opening addition to the hydroxyl group in component (A), thereby obtaining a structure in which a carboxyl group is present at the terminal of a molecular chain branched from the molecular chain derived from component (A) and not containing a urethane bond.

[0149] The remaining hydroxyl groups in component (A) that have not reacted with component (B) react with the polyisocyanate compound (E) in step 2 to form urethane bonds. This forms molecular chains branching from the molecular chain derived from component (A) and containing urethane bonds.

[0150] The ratio (mass ratio) of the component (A) to the component (B) reacted in the first step is represented by A:B, and A:B is preferably 1:0.1 to 1:10.

[0151] When the ratio of the component (A) to the component (B) is at least the lower limit of the above range, the resin composition will be excellent in water dispersion stability, and when it is at most the upper limit, the resin composition will be excellent in flexibility.

[0152] The molar ratio of the hydroxyl groups present in component (A) to the acid anhydride groups present in component (B) reacted in the first step is expressed as hydroxyl groups:acid anhydride groups, and is preferably 1:0.05 to 1:0.9, more preferably 1:0.1 to 1:0.7. When the molar ratio of the acid anhydride groups to the hydroxyl groups is at least the lower limit of the above range, the resin composition exhibits excellent water dispersion stability, while when it is at most the upper limit, the resin composition exhibits excellent flexibility.

[0153] The first step is carried out in the presence of a polymerization inhibitor.

[0154] The polymerization inhibitor is a compound that inhibits the polymerization reaction of the free radical polymerizable unsaturated bonds of the (meth)acryloyl group. Known polymerization inhibitors can be used. Specific examples of polymerization inhibitors include methoxyhydroquinone, phenothiazine, and 2,6-di-tert-butyl-4-hydroxytoluene.

[0155] The amount of the polymerization inhibitor used is preferably 0.001% to 1% by mass, more preferably 0.005% to 0.5% by mass, and even more preferably 0.01% to 0.1% by mass, relative to the final urethane (meth)acrylate (a). When the amount of the polymerization inhibitor used is at least the lower limit of the above range, the storage stability of the urethane (meth)acrylate is improved, while when it is at most the upper limit, the ultraviolet curability of the urethane (meth)acrylate is improved.

[0156] The first step is preferably carried out in the presence of an esterification catalyst.

[0157] Specific examples of the esterification catalyst include triphenylphosphine and tetrabutylammonium bromide.

[0158] The amount of the esterification catalyst used is preferably 0.01% to 10% by mass, more preferably 0.05% to 5% by mass, and even more preferably 0.1% to 3% by mass, relative to the total amount of components (A) and (B). When the amount of the esterification catalyst used is at least the lower limit of the above range, the reaction rate is improved, while when it is at most the upper limit, the storage stability is improved.

[0159] The reaction temperature in the first step is, for example, 30°C to 130°C, or further 60°C to 100°C.

[0160] The reaction time of the first step is, for example, 1 to 24 hours, and further 1 to 8 hours.

[0161] <Step 2>

[0162] In the second step, the hydroxyl groups in the components (C) and (D) and the isocyanate groups in the component (E) undergo an addition reaction to produce the compound (a).

[0163] Specifically, the hydroxyl groups in component (C), i.e., the hydroxyl groups that did not react with component (B) in step 1, react with the isocyanate groups in component (E) to form a urethane bond. Separately, the isocyanate groups in component (E) react with the hydroxyl groups in component (D) to form a urethane bond.

[0164] The ratio of the components (C), (D), and (E) to be reacted in the second step is preferably set so that the urethane bond concentration in the compound (a) falls within the above-mentioned preferred range.

[0165] In the second step, it is preferred that substantially all of the isocyanate groups in the component (E) react.

[0166] The infrared absorption spectrum of the product produced in the second step can be measured based on the wavelength of 2200 cm where the isocyanate residue is no longer observed. -1 ~2300cm -1 It was determined that substantially all of the isocyanate groups in the component (E) had reacted.

[0167] For example, the ratio (mass ratio) of the components (C), (D), and (E) reacted in the second step is expressed as C:D:E. It is preferable that C:D:E be set within the range of 1:0.1:0.1 to 1:10:10.

[0168] When the ratio of the components (C), (D), and (E) is at least the lower limit of the above range, the flexibility is excellent, and when it is at most the upper limit, the water dispersion stability of the resin composition is excellent.

[0169] The second step is preferably carried out in the presence of the same polymerization inhibitor as in the first step. The second step is preferably carried out by adding the components (D) and (E) to the reaction solution after the first step.

[0170] From the viewpoint of shortening the reaction time, the second step may be performed in the presence of a urethanization catalyst.

[0171] A known urethanization catalyst can be used, and specific examples include organometallic compounds such as dibutyltin acetate, dibutyltin dilaurate, and dioctyltin dilaurate, and basic compounds such as triethylenediamine and triethylamine.

[0172] The amount of the urethanization catalyst used can be appropriately adjusted according to the activity of the catalyst used, and is, for example, preferably 0 to 1% by mass, more preferably 0 to 0.5% by mass, and even more preferably 0 to 0.1% by mass relative to the urethane (meth)acrylate (a).

[0173] <<Neutralizer>>

[0174] The neutralized product of one embodiment of the present invention (hereinafter also referred to as "the present neutralized product") is a product obtained by neutralizing the carboxyl groups in compound (a) with an amine compound. Neutralization of the carboxyl groups with an amine compound further improves water dispersibility or water solubility.

[0175] In the neutralized product, the carboxyl groups present in compound (a) may be completely or partially neutralized. To achieve better water dispersibility or water solubility, the proportion of carboxyl groups neutralized with the amine compound is preferably 80 mol% or greater, and more preferably 95 mol% or greater, per 100 mol% of all carboxyl groups in the neutralized product. A higher proportion of carboxyl groups neutralized with the amine compound tends to result in better water dispersibility or water solubility.

[0176] The amine compound may be any compound as long as it has an amino group and can neutralize a carboxyl group.

[0177] Examples of the amine compound include aliphatic primary amines such as methylamine, ethylamine, propylamine, isopropylamine, butylamine, amylamine, hexylamine, octylamine, 2-ethylhexylamine, nonylamine, decylamine, laurylamine, pentadecylamine, hexadecylamine, stearylamine, and cyclohexylamine; aliphatic secondary amines such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, diamylamine, dihexylamine, dioctylamine, di(2-ethylhexyl)amine, didecylamine, dilaurylamine, dihexadecylamine (DicetylAmine), distearylamine, methylstearylamine, ethylstearylamine, and butylstearylamine; and trimethylamine, triethylamine, tripropylamine, tributylamine, trioctylamine, trilaurylamine, tridecylamine, tristearylamine, triisopropylamine, diisopropylamine, dibutylamine, diamylamine, dihexylamine, dioctylamine, di(2-ethylhexyl)amine, didecylamine, dilaurylamine, dihexadecylamine (DicetylAmine), distearylamine, methylstearylamine, ethylstearylamine, and butylstearylamine. Amine, triisobutylamine, tri-2-ethylhexylamine, tri-branched tridecylamine, N,N-dimethylethylamine, N,N-dimethylpropylamine, N,N-dimethylisopropylamine, N,N-dimethylbutylamine, N,N-dimethylisobutylamine, N,N-dimethyloctylamine, N,N-dimethyl-2-ethylhexylamine, N,N-dimethyllauramine, N,N-dimethyl (branched) tridecylamine, N,N-dimethylstearylamine, N,N-diethylbutylamine, N,N-diethylhexylamine, N,N-diethyloctylamine, N,N-diethyl-2-ethylhexylamine, N,N-diethyllauramine, N,N-diisopropylmethylamine, N,N-diisopropylethylamine, N,N-diisopropyl Butylamine, N,N-diisopropyl-2-ethylhexylamine and other aliphatic tertiary amines; N,N-dimethylcyclohexylamine, N,N-diethylbenzylamine, N,N-diethylcyclohexylamine, N,N-dicyclohexylmethylamine, N,N-dicyclohexylethylamine, tricyclohexylamine and other alicyclic tertiary amines; N,N-dimethylbenzylamine, N,N-diethylbenzylamine, N,N-dibenzylmethylamine, tribenzylamine, N,N-dimethyl-4-methylbenzylamine, N,N-dimethylphenylamine, N,N-diethylphenylamine, N,N-diphenylmethylamine and other aromatic tertiary amines; N-methylpyrrolidine, N-ethylpyrrolidine, N-propylpyrrolidine, N-butylpyrrolidine, N-methylpiperidine, Cyclic amines such as N-ethylpiperidine, N-propylpiperidine, N-butylpiperidine, N-methylmorpholine, N-ethylmorpholine, N-propylmorpholine, N-butylmorpholine, N-sec-butylmorpholine, N-tert-butylmorpholine, N-isobutylmorpholine, and quinuclidine; other amines such as monoethanolamine, diethanolamine, triethanolamine, 3-hydroxypropylamine, ethylenediamine, propylenediamine, hexamethylenediamine, N-methyl-1,3-propylenediamine, diethylenetriamine, triethylenetetramine, 2-(2-aminoethylamino)ethanol, benzylamine, 3-methoxypropylamine, 3-lauryloxypropylamine, xylylenediamine, 2,4,6-tris(dimethylaminomethyl)phenol, and polyoxypropylenediamine.

[0178] The amine compounds may be used alone or in combination of two or more.

[0179] From the viewpoint of solubility in water, the amine compound carboxylic acid is preferably a compound having a tertiary amino group, and triethylamine is particularly preferred.

[0180] The neutralized product can be produced, for example, by contacting the compound (a) with an amine compound. The temperature during the contact is, for example, 20° C. to 70° C., and the contact time is, for example, 10 minutes to 60 minutes.

[0181] <<Aqueous resin composition>>

[0182] The aqueous resin composition according to one embodiment of the present invention is obtained by dispersing the neutralized product in water.

[0183] Specifically, the compound (a) is brought into contact with an amine compound to obtain the neutralized product, and then water is gradually added while stirring the neutralized product and mixed until the mixture is emulsified to obtain an aqueous resin composition (emulsified dispersion).

[0184] The content of the neutralized product in the aqueous resin composition is, for example, preferably 10 to 60% by mass, more preferably 15 to 50% by mass, and even more preferably 20 to 40% by mass relative to the total mass of the aqueous resin composition.

[0185] Since the neutralized product has excellent water solubility or water dispersibility, the average particle size of the aqueous resin composition is small. In addition, the aqueous resin composition has excellent dispersion stability.

[0186] For example, an aqueous resin composition having an average particle size of 10 nm to 200 nm, preferably 10 nm to 100 nm, and more preferably 10 nm to 50 nm at a measurement temperature of 25° C. can be obtained.

[0187] <<Aqueous active energy ray-curable composition>>

[0188] The aqueous active energy ray-curable composition according to one embodiment of the present invention (hereinafter also referred to as the "present curable composition") comprises the aqueous resin composition and a photopolymerization initiator. Specifically, the present curable composition comprises the present neutralized product, water, and a photopolymerization initiator.

[0189] The photopolymerization initiator is a substance that generates active species such as radicals and / or cations by initiator cleavage and / or hydrogen migration caused by irradiation with active energy rays.

[0190] The present curable composition may further contain a monomer having a polymerizable unsaturated bond (polymerizable carbon-carbon double bond, etc.) (hereinafter also referred to as "other monomer") other than the present neutralized product and compound (a).

[0191] The present curable composition may further contain a non-reactive diluent as needed.

[0192] The present curable composition may further contain other components besides those described above, as necessary.

[0193] <Photopolymerization Initiator>

[0194] Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, benzyl dimethyl ketal, 1-hydroxycyclohexyl-phenyl ketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, Benzoylphenylethoxyphosphine oxide, benzophenone, methyl o-benzoylbenzoate, hydroxybenzophenone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 2,4,6-tris(trichloromethyl)-s-triazine, 2-methyl-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, iron-arene complexes, titanocene compounds, and the like, and one or more thereof can be used.

[0195] <Other monomers>

[0196] The other monomer may be a monofunctional monomer having one polymerizable unsaturated bond or a polyfunctional monomer having two or more polymerizable unsaturated bonds. A monofunctional monomer and a polyfunctional monomer may be used in combination.

[0197] The monomer is preferably a water-soluble monomer. "Water-soluble monomer" refers to a monomer that forms a homogeneous solution when mixed with water.

[0198] Examples of the monofunctional monomer include hydroxyl group-containing monofunctional (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl acrylate, and 4-hydroxybutyl acrylate, acryloylmorpholine, dimethylacrylamide, and isobornyl acrylate.

[0199] Examples of the polyfunctional monomer include hydroxyl-containing polyfunctional (meth)acrylates such as pentaerythritol di- or tri-(meth)acrylate, dipentaerythritol di-, tri-, tetra- or penta-(meth)acrylate, DPH(M)A, PET(M)A, tripropylene glycol diacrylate, and trimethylolpropane triacrylate.

[0200] These monomers may be used alone or in combination of two or more.

[0201] <Non-reactive diluent>

[0202] The non-reactive diluent is a compound that does not have a polymerizable unsaturated bond and is liquid at room temperature.

[0203] Examples of the non-reactive diluent include organic solvents such as methanol, ethanol, isopropyl alcohol, propylene glycol monomethyl ether, methyl ethyl ketone, ethyl acetate, butyl acetate, and toluene, and water. These non-reactive diluents may be used alone or in combination of two or more.

[0204] As the non-reactive diluent, ketone solvents such as methyl ethyl ketone and ester solvents such as ethyl acetate are preferred from the viewpoint of excellent dilutability and workability in the drying step.

[0205] <Other ingredients>

[0206] Other components include additives such as thermal polymerization inhibitors, ultraviolet absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial agents, antifungal agents, defoaming agents, leveling agents, fillers, thickeners, adhesion-imparting agents, thixotropy-imparting agents, and glazing agents.

[0207] <Content of each ingredient>

[0208] The content of the neutralized product is preferably 30% to 95% by mass, more preferably 50% to 95% by mass, relative to the total mass of the curable composition. If the content of the neutralized product is greater than the above lower limit, the water dispersion stability of the resin composition and the flexibility of the cured product are further improved.

[0209] The content of other monomers is preferably 0% to 50% by mass, more preferably 0% to 30% by mass, relative to the total mass of the curable composition. If the content of other monomers is below the above upper limit, the water dispersion stability of the resin composition and the flexibility of the cured product will be further improved.

[0210] Relative to the total content of this neutralized product and other monomers, the ratio of this neutralized product is preferably 80% by mass or more, more preferably 90% by mass or more, and may be 100% by mass. If the ratio of this neutralized product is above the above lower limit, the water dispersion stability of the resin composition and the flexibility of the cured product are more excellent.

[0211] The content of the photopolymerization initiator is preferably 0.1% to 10% by mass, more preferably 1% to 7% by mass, relative to the total mass of the curable composition. If the content of the photopolymerization initiator is at least the lower limit, the photocurability of the curable composition is further improved, while if it is at most the upper limit, the storage stability of the curable composition is further improved.

[0212] The content of the non-reactive diluent is preferably 0% to 80% by mass, more preferably 0% to 60% by mass, relative to the total mass of the curable composition. If the content of the non-reactive diluent is below the upper limit, the water dispersion stability of the resin composition will be further improved.

[0213] The present curable composition can be produced by mixing the present neutralized product, a photopolymerization initiator, and at least one selected from the group consisting of other monomers and other components as needed. The order of mixing the components is not particularly limited.

[0214] <<Cured product>>

[0215] The present curable composition can be cured by irradiation with active energy rays to form a cured product.

[0216] When the curable composition is irradiated with active energy rays, active species (radicals, cations) are generated from the photopolymerization initiator. These active species act on the neutralized product and other monomers to cause polymerization or crosslinking reactions, thereby curing the curable composition.

[0217] Examples of active energy rays include visible light, ultraviolet rays, plasma, infrared rays, and ionizing radiation. Among them, ultraviolet rays are preferred from the viewpoint of widespread use of irradiation devices.

[0218] The irradiation conditions of the active energy ray can be appropriately selected according to the light source used. For example, the cumulative light intensity during ultraviolet ray irradiation is 50 mJ / cm 2 ~1000mJ / cm 2 .

[0219] The cured product of the present curable composition has excellent flexibility.

[0220] For example, a cured product having a Shore D hardness of 45 or less, preferably 40 or less, and more preferably 35 or less can be obtained.

[0221] Since the neutralized product contained in the curable composition has high water solubility or water dispersibility, the ratio of the hard segment in the cured product is reduced, and a soft cured product (cured film) can be obtained.

[0222] <<Applications of the aqueous active energy ray-curable composition>>

[0223] The present curable composition can be used in applications such as soft coatings, adhesives, sealants, inks, and resists. Furthermore, the present curable composition can be used in applications using curable elastomers.

[0224] From the viewpoint of being able to form a flexible cured film, the present curable composition is suitable as a soft coating agent and an adhesive.

[0225] [Soft coating agent]

[0226] The soft coating agent formed from the present curable composition can be used to form a soft coating layer on the surface of a substrate.

[0227] For example, a soft coating agent is applied to the surface of a substrate and dried as needed to form a coating film composed of the soft coating agent. Subsequently, the coating film is irradiated with light to cure it, thereby forming a soft coating layer (cured film) composed of a cured product of the soft coating agent. Thus, a substrate with a soft coating layer is obtained.

[0228] Examples of the substrate include films, sheets, and various other molded products. Films are preferred from the perspective of handleability and processability. The thickness of the film is, for example, 10 μm to 250 μm.

[0229] Examples of the material of the substrate include resin, metal, glass, and wood. Examples of the resin include polyesters such as polyethylene terephthalate (PET), polycarbonate resins, and ABS resins.

[0230] As the coating method, a known coating method can be appropriately adopted, and examples thereof include spray coating, spin coating, and gravure coating.

[0231] Drying conditions may be any conditions as long as the non-reactive diluent can be removed, and examples thereof include drying at 60° C. to 110° C. for 0.5 to 10 minutes.

[0232] The light irradiation conditions were the same as above.

[0233] The thickness of the coating film is set according to the thickness of the soft coating layer to be formed.

[0234] The thickness of the soft coating layer may be, for example, 1 μm to 20 μm.

[0235] [Adhesive]

[0236] The adhesive formed from the present curable composition forms an adhesive layer between a substrate and an adherend, and can be used to integrate the substrate and the adherend via the adhesive layer.

[0237] For example, an adhesive is applied to the surface of a substrate, an adherend is stacked thereon, and the adhesive is dried as needed to form a coating of the adhesive. Subsequently, the coating is irradiated with light to cure the adhesive, thereby forming an adhesive layer (cured film) composed of a cured product of the adhesive. Thus, the substrate and the adherend are integrated via the adhesive layer to obtain a laminate.

[0238] As for the materials of the substrate and the adherend, the same materials as those of the substrate in the above-mentioned substrate with a soft coating layer can be exemplified.

[0239] Examples of the adhesive coating method, drying conditions, and light irradiation conditions include the same methods as those used in the production of the soft-coated substrate.

[0240] The thickness of the adhesive layer can be, for example, 1 μm to 20 μm.

[0241] Example

[0242] Hereinafter, the present invention will be described in detail with reference to Examples.

[0243] Hereinafter, "parts" means "parts by mass".

[0244] <Abbreviation>

[0245] [Polyisocyanate compound (E)]

[0246] IPDI: Isophorone diisocyanate (“IPDI” manufactured by Evonik Japan Co., Ltd.).

[0247] HDI: Hexamethylene diisocyanate (“HDI” manufactured by Tosoh Corporation).

[0248] TDI: toluene diisocyanate ("Coronate T-100" manufactured by Tosoh Corporation).

[0249] [Hydroxy acrylate]

[0250] HEA: 2-hydroxyethyl acrylate.

[0251] [Production Example 1: Production of Urethane Acrylate Compound]

[0252] In a four-necked flask equipped with a thermometer, a cooling tube, and a stirring device, 298 parts of 1,6-hexanediol diglycidyl ether acrylic acid adduct as component (A), 118 parts of phthalic anhydride as component (B), 5.0 parts of triphenylphosphine, and 0.5 parts of 2,6-di-tert-butyl-p-cresol were added. After sufficient stirring, the temperature was raised to 80°C and stirred and heated for about 3 hours to react to produce component (C) (first step). Next, 407 parts of polybutylene glycol (Mw = 1011, hydroxyl value = 111 mgKOH / g) as component (D) and 177 parts of isophorone diisocyanate as component (E) were added. After sufficient stirring, the temperature was raised to 80°C and stirred and heated for about 24 hours to react. After the reaction, it was confirmed by infrared absorption spectroscopy that no isocyanate residue was observed (second step). In this way, a urethane acrylate compound (a) was obtained.

[0253] The weight average molecular weight (Mw), double bond equivalent, acid value, and urethane bond concentration relative to the total mass of the urethane acrylate compound obtained are shown in Table 1 (the same applies hereinafter).

[0254] It should be noted that, although it is obvious to those skilled in the art, the double bond equivalent is calculated using the formula: "(molar ratio of component (A) × molecular weight + molar ratio of component (B) × molecular weight + molar ratio of component (D) × molecular weight + molar ratio of component (E) × molecular weight) / molar ratio of component (A) × number of double bonds in component (A)." The urethane bond concentration is calculated using the formula: "number of moles of component (E) × number of isocyanate groups in component (E) × 43 / total mass of urethane acrylate × 100."

[0255] [Production Examples 2 to 11]

[0256] Except that the types and amounts of the materials added to the four-necked flask were as shown in Table 1, the same procedure as in Production Example 1 was carried out to obtain a urethane acrylate compound (a).

[0257] In the following Comparative Production Examples 1 and 2, hydroxyethyl acrylate and dihydroxycarboxylic acid were used instead of the component (A) and the component (B).

[0258] [Comparative Production Example 1]

[0259] In a four-necked flask equipped with a thermometer, cooling tube, and stirring device, 232 parts of polybutylene glycol (component (D)), 382 parts of hexamethylene diisocyanate (component (E)), 122 parts of dimethylolpropionic acid, 264 parts of hydroxyethyl acrylate, and 0.5 parts of 2,6-di-tert-butyl-p-cresol were added. After thorough stirring, the temperature was raised to 80°C and stirred for approximately 24 hours to allow the reaction to proceed. After the reaction, infrared absorption spectroscopy confirmed that no isocyanate residues were observed. This yielded urethane acrylate.

[0260] [Comparative Production Example 2]

[0261] Urethane acrylate was obtained in the same manner as in Production Example 1 except that the types and amounts of the materials added to the four-necked flask were as shown in Table 1.

[0262] [Example 1]

[0263] (Production of Neutralized Product and Aqueous Resin Composition)

[0264] Into a flask equipped with a stirring device, 35 parts of the urethane acrylate obtained in Production Example 1 and 2.8 parts of triethylamine were added, and the mixture was stirred for about 1 hour while maintaining the liquid temperature at 60°C to obtain a neutralized product. Then, 65 parts of water was slowly added while stirring and mixed into a homogeneous emulsified state to obtain an emulsified dispersion (aqueous resin composition) in which the neutralized product was dispersed in water.

[0265] The ratio of the carboxyl groups neutralized by the amine compound in 100 mol% of all the carboxyl groups in the obtained neutralized product is shown in Table 2 (the same applies hereinafter).

[0266] The average particle size of the obtained aqueous resin composition was measured using a dynamic light scattering measuring apparatus (Microtrac BEL product name "NANOTRAC-flEx"). The results are shown in Table 2 (the same applies hereinafter).

[0267] The dispersion stability of the obtained aqueous resin composition was evaluated by the following method. The results are shown in Table 3 (the same applies hereinafter).

[0268] (Production of aqueous active energy ray-curable composition)

[0269] Using the obtained aqueous resin composition, an aqueous active energy ray-curable composition was produced.

[0270] Specifically, 100 parts of the emulsified dispersion (aqueous resin composition) obtained above and 1.1 parts of 4'-(2-hydroxyethoxy)-2-hydroxy-2-methylacetone (product name "Omnirad 2959" of IGM Resins BV, hereinafter referred to as "Omnirad 2959") as a photopolymerization initiator were added to a flask equipped with a stirring device, and the mixture was stirred for about 1 hour to obtain a liquid resin composition (aqueous active energy ray-curable composition).

[0271] (Manufacturing of Cured Products and Base Materials with Cured Films)

[0272] The obtained aqueous active energy ray-curable composition was applied onto a 100 μm thick substrate film (highly adhesive PET) to a predetermined film thickness after drying, and dried at 100° C. to form a coating film.

[0273] Then, the coating film was irradiated with ultraviolet rays so that the cumulative light intensity was 500 mJ / cm 2 , forming a cured film (cured product) to obtain a PET film with a cured film.

[0274] The obtained film with a cured coating was evaluated for flexibility based on the following evaluation criteria.

[0275] The results are shown in Table 3 (the same applies hereinafter).

[0276] <Evaluation Method of Dispersion Stability>

[0277] The homogeneous emulsified dispersion (aqueous resin composition) obtained in each example was allowed to stand while maintaining a constant liquid temperature, and visually observed for solid separation and precipitation. The liquid temperature was set at 25°C and 40°C. The day the aqueous resin composition was prepared was designated as Day 1, and observations were made daily to measure the number of days until precipitation occurred.

[0278] The average particle size immediately after production (immediately after production) and the average particle size on the 14th day (after standing) were measured for the emulsified dispersion allowed to stand at 25° C. The average particle size of the liquid in which a precipitate separated was designated as “unmeasurable”.

[0279] The dispersion stability was evaluated according to the following evaluation criteria.

[0280] (Evaluation Criteria)

[0281] ⊚: No separation precipitate was generated on the 14th day, and the absolute value of the difference in average particle size between immediately after production and after standing was less than 40 nm.

[0282] ◯: No separation precipitate was generated on the 14th day, and the absolute value of the difference in average particle size between immediately after production and after standing was 40 nm or more.

[0283] Δ: Separate precipitates were generated from the 2nd to the 14th day.

[0284] ×: Separate precipitate was generated on the first day.

[0285] <Evaluation Method of Flexibility>

[0286] (1) Bending evaluation

[0287] The PET film with the cured coating (the cured coating had a thickness of 1 mm after drying) was manually bent 180° with the cured coating facing inward. The bending resistance was evaluated according to the following criteria.

[0288] (Evaluation Criteria)

[0289] ○: No cracks were generated when bent.

[0290] ×: Cracks occurred when bent.

[0291] (2) Shore D hardness

[0292] The Shore D hardness of a PET film with a cured film (the cured film thickness after drying was 8 mm) was measured using a D-type durometer in accordance with JIS K 6253-3:2012.

[0293] [Examples 2 to 11, Comparative Examples 1 and 2]

[0294] The same procedures as in Example 1 were followed, except that the types and amounts of materials added to the flask were as shown in Table 2, to obtain an emulsified dispersion (aqueous resin composition), produce an aqueous active energy ray-curable composition, and produce a substrate with a cured film. Evaluations were performed in the same manner as in Example 1.

[0295]

Table 1

[0296]

[0297]

Table 2

[0298]

[0299]

Table 3

[0300]

[0301] As shown in the results in Tables 1 to 3, the aqueous resin compositions of Examples 1 to 11 (formed by dispersing the neutralized urethane acrylate compound (a) obtained in Production Examples 1 to 11 in water) have a small average particle size. This indicates that the neutralized urethane acrylate compound (a) has excellent water dispersibility.

[0302] Furthermore, the aqueous resin compositions of Examples 1 to 11 were less likely to separate and precipitate during storage and were excellent in dispersion stability.

[0303] Furthermore, the cured products (cured films) of the aqueous active energy ray-curable compositions of Examples 1 to 11 exhibited excellent flexural resistance, low Shore D hardness, and excellent flexibility. These properties are believed to be achieved by significantly improving water solubility or water dispersibility by introducing carboxyl groups into the ends of the molecular chains of the urethane acrylate compound (a), which branch from the molecular chain derived from the epoxy (meth)acrylate compound (A) and do not contain urethane bonds. Furthermore, this significant improvement in water solubility or water dispersibility reduces the proportion of hard segments in the cured product, resulting in a softer cured film.

[0304] On the other hand, the dispersed emulsions of Comparative Examples 1 and 2 obtained by dispersing the neutralized urethane acrylate compounds obtained in Comparative Preparation Examples 1 and 2 in water had large average particle sizes, were prone to separation and precipitation during storage, and had poor water dispersibility.

[0305] Furthermore, the cured products (cured films) of the aqueous active energy ray-curable compositions of Comparative Examples 1 and 2 cracked when bent at 180°, had high Shore D hardness, and were poor in flexibility.

[0306] In the urethane acrylate compounds obtained in Comparative Production Examples 1 and 2, the carboxyl groups exist as pendant groups on the molecular chain between two urethane bonds derived from the hydroxyl groups of the dihydroxycarboxylic acid. Specifically, the carboxyl groups between the highly cohesive urethane bonds are contained within the hard segments, and the effect of improving water solubility or water dispersibility due to the introduction of the carboxyl groups cannot be fully achieved.

Claims

1. A urethane (meth)acrylate compound, which is obtained by reacting a carboxyl group-containing epoxy (meth)acrylate compound (C), a polyol compound (D), and a polyisocyanate compound (E). The carboxyl group-containing epoxy (meth)acrylate compound (C) is obtained by reacting an epoxy (meth)acrylate compound (A) with an acid anhydride (B). in, The urethane (meth)acrylate compound has one or more urethane bonds, one or more (meth)acryloyl groups, and one or more carboxyl groups in one molecule. At least one carboxyl group is present in a molecular chain branched from a molecular chain derived from the epoxy (meth)acrylate compound (A) and not containing a urethane bond.

2. The urethane (meth)acrylate compound according to claim 1, wherein The double bond equivalent is 100 to 10,000.

3. The urethane (meth)acrylate compound according to claim 1, wherein The acid value is 10KOHmg / g to 500KOHmg / g.

4. The urethane (meth)acrylate compound according to claim 1, wherein The content of the urethane bond is 1% by mass to 50% by mass relative to the total mass of the urethane (meth)acrylate compound.

5. The urethane (meth)acrylate compound according to claim 1, wherein The epoxy (meth)acrylate compound (A) is at least one selected from aliphatic epoxy (meth)acrylate, alicyclic epoxy (meth)acrylate, and aromatic epoxy (meth)acrylate.

6. The urethane (meth)acrylate compound according to claim 1, wherein The acid anhydride (B) is at least one selected from aliphatic acid anhydrides, alicyclic acid anhydrides, and aromatic acid anhydrides.

7. The urethane (meth)acrylate compound according to claim 1, wherein The polyol compound (D) is at least one selected from polyether polyol, polycarbonate polyol, and polyester polyol.

8. The urethane (meth)acrylate compound according to claim 1, wherein The polyisocyanate compound (E) is at least one selected from aliphatic polyisocyanates, alicyclic polyisocyanates, and aromatic polyisocyanates. 9 . A neutralized product obtained by neutralizing the urethane (meth)acrylate compound according to claim 1 with an amine compound.

10. An aqueous resin composition, which is obtained by dispersing the neutralized product according to claim 9 in water.

11. The aqueous resin composition according to claim 10, wherein The average particle size is 10nm~200nm. 12 . An aqueous active energy ray-curable composition comprising the aqueous resin composition according to claim 10 and a photopolymerization initiator. 13 . A cured product, which is a cured product of the aqueous active energy ray-curable composition according to claim 12 .

14. The cured product according to claim 13, wherein The Shore D hardness is 45 or less.

15. A substrate with a cured coating, wherein: A cured film formed of the cured product according to claim 13 is provided on the surface of a substrate. 16 . A soft coating agent, an adhesive, a sealant, an ink, or a resist, comprising the aqueous active energy ray-curable composition according to claim 12 .

17. A substrate with a soft coating, wherein: A soft coating layer formed of the cured product according to claim 13 is provided on the surface of a substrate.

18. A laminated body, wherein: An adhesive layer formed of the cured product according to claim 13 is provided between a substrate and an adherend.

19. A method for producing a urethane (meth)acrylate compound, wherein: include: a step of reacting the epoxy (meth)acrylate compound (A) and the acid anhydride (B) to obtain a carboxyl group-containing epoxy (meth)acrylate compound (C); and A step of reacting the obtained carboxyl group-containing epoxy (meth)acrylate compound (C), the polyol compound (D), and the polyisocyanate compound (E).

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