Sclerotic resin composition and cured product thereof

Abstract

Provided is a curable composition capable of forming a hard coat layer excellent in heat resistance and heat and moisture resistance. 【Solution means】A composition comprising a (meth)acrylate having a hydroxyl value in a specific range and having a structure derived from a polyhydric alcohol, a urethane (meth)acrylate obtained from a specific polyvalent isocyanate, and a mixture of (meth)acrylates having a number of alkylene oxide structural units in a different specific range.

Description

Technical Field

[0001] The present invention relates to a curable resin composition and a cured product thereof, which contain a urethane (meth) acrylate obtained from a (meth) acrylate having a specific hydroxyl value and having a structure derived from a polyhydric alcohol and a specific polyvalent isocyanate, and a mixture of polyfunctional (meth) acrylates having different numbers of alkylene oxide units.

Background Art

[0002] In recent years, resin films and molded products such as polyethylene terephthalate (PET) resin, polycarbonate (PC) resin, poly(methyl methacrylate) (PMA or PMMA) resin, etc. have been widely used in many devices such as liquid crystal televisions, mobile phones, communication devices, office equipment, and household appliances and their parts instead of glass substrates and molded products. These resins are lighter in weight and easier to process than glass, but are inferior in weather resistance and the surface is easily damaged, so it is generally practiced to provide a protective layer. For this reason, the protective layer is required to have hardness and scratch resistance, but is also used for bent portions such as molded products and displays. In recent years, since it has also started to be used for foldable or rollable portable display devices, high flexibility has been required. In addition, when a coating agent is applied on a film and cured, it is also required that curling and cracking due to curing shrinkage do not occur.

[0003] In addition, for devices used outdoors such as devices mounted on automobiles and portable devices, higher heat resistance and resistance to moist heat are required.

[0004] In response to such requirements, various curable resin compositions have been proposed as coating agents for resin substrates.

[0005] For example, for the purpose of providing a coating agent capable of forming a coating layer that combines high hardness and high flexibility, an active energy ray-curable coating agent containing a mixture of urethane acrylates synthesized from pentaerythritol acrylate (PETA) with different hydroxyl values and inorganic fine particles has been proposed (Patent Document 1).

[0006] Also, for the purpose of providing a curable composition that has a viscosity suitable for spray coating even at a high solid content, suppresses the precipitation of an ultraviolet absorber, and can obtain a cured product excellent in weather resistance and hot water resistance, a curable composition containing a multi-branched acrylate, a bifunctional urethane acrylate, an ultraviolet absorber, and a photopolymerization initiator in a predetermined ratio has been proposed (Patent Document 2).

[0007] Also, for the purpose of providing a curable resin composition capable of forming a hard coat layer with high hardness without generating curl or cracks during the formation or processing of the hard coat layer, a urethane (meth)acrylate (A) which is a reaction product of norbornane diisocyanate (a1) and a compound (a2) having a hydroxyl group and a (meth)acryloyl group, and a bifunctional (meth)acrylate monomer (B) in which an ethoxy structure is introduced between the terminal (meth)acryloyl groups are contained in a predetermined ratio (Patent Document 3).

[0008] Also, for the purpose of providing a coating material composition capable of forming a crosslinked cured film excellent in weather resistance while improving the abrasion resistance, particularly the abrasion resistance by the Taber abrasion test, on the surface of a substrate, a (iso)cyanurate compound having a polyfunctional (meth)acryloyl group as a main component, polypentaerythritol having a (meth)acryloyl group, a urethane poly(meth)acrylate compound having a radically polymerizable unsaturated double bond, a cyanurate having a (meth)acryloyl group, an ultraviolet absorber, a hindered amine light stabilizer, and a photopolymerization initiator are provided (Patent Document 4).

[0009] However, none of these coating agents and curable compositions aim to improve in terms of heat resistance and heat and humidity resistance, and are insufficient in terms of adhesion and transparency under high heat or high heat and humidity conditions of the resulting cured product. For this reason, there is still a demand for a curable composition that can impart high heat resistance and heat and humidity resistance.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0011] In one embodiment, the present invention aims to provide a curable composition capable of forming a hard coat layer excellent in heat resistance and heat and humidity resistance in response to such demands. In another embodiment, the present invention also aims to provide a cured product excellent in heat resistance and heat and humidity resistance, or a product having the same.

Means for Solving the Problems

[0012] The inventor has conducted various studies on the composition of the curable composition to achieve the above object, and found that a (meth)acrylate having a hydroxyl value within a specific range having a structure derived from a polyhydric alcohol, more preferably a mixture of (meth)acrylates having different hydroxyl values within specific ranges having a structure derived from a polyhydric alcohol, and a urethane (meth)acrylate obtained from a specific polyisocyanate and a mixture of (meth)acrylates having different specific numbers of alkylene oxide structural units. When the composition was cured on a resin substrate, it was found that the resulting cured product maintained adhesion and transparency even after being exposed to high heat conditions or high humidity and heat conditions for a long time, leading to the present invention.

[0013] That is, the present invention provides, in its embodiments, the following curable resin composition, cured layer, method for forming the same, and article having the same. [1] A urethane (meth)acrylate (A) obtained by reacting a (meth)acrylate (a1) having a hydroxyl value of 90 to 300 mgKOH / g having a structure derived from a polyhydric alcohol, an aliphatic isocyanate, an alicyclic isocyanate having no crosslinked structure, an aromatic isocyanate, and a hydrogenated product thereof, a polyisocyanate (a2) selected therefrom, and optionally a polyol (a3), and an alkylene oxide-modified (meth)acrylate (B) and comprising, wherein the alkylene oxide-modified (meth)acrylate (B) is a (meth)acrylate (B1) having an average number of repeating units of alkylene oxide of 0 to 2.0, optionally, a (meth)acrylate (B2) having an average number of repeating units of alkylene oxide of 3.0 to 5.0, and a (meth)acrylate (B3) having an average number of repeating units of alkylene oxide of 6.0 to 8.0, a curable resin composition. [2] The alkylene oxide-modified (meth)acrylate (B) is represented by the following formula (1):

Chemical formula

[10] The polyvalent isocyanate (a2) is an alicyclic isocyanate having no crosslinked structure, and is the curable resin composition according to any one of [1] to [9].

[11] The alicyclic isocyanate is isophorone diisocyanate or dicyclohexylmethane diisocyanate, and is the curable resin composition according to

[10] .

[12] The hydroxyl value of the urethane (meth)acrylate (A) is 0.1 to 10 mgKOH / g, and is the curable resin composition according to any one of [1] to

[11] .

[13] The alkylene oxide-modified (meth)acrylate (B) is selected from ethylene oxide-modified trimethylolpropane triacrylate, propylene oxide-modified trimethylolpropane triacrylate, ethylene oxide-modified bisphenol A diacrylate, propylene oxide-modified bisphenol A diacrylate, ethylene oxide-modified pentaerythritol tetraacrylate, and propylene oxide-modified pentaerythritol tetraacrylate, and is the curable resin composition according to any one of [1] to

[12] .

[14] The curable resin composition according to any one of [1] to

[13] contains 0.01 to 10 parts by mass of a polymerization initiator with respect to a total of 100 parts by mass of the urethane (meth)acrylate (A) and the (meth)acrylate (B).

[15] The polymerization initiator is one or more thermal polymerization initiators selected from azo compound-based polymerization initiators and organic peroxide-based polymerization initiators, and is the curable resin composition according to

[14] .

[16] The curable resin composition according to

[14] , wherein the polymerization initiator is at least one photoinitiator selected from the group consisting of acetophenone-based polymerization initiators, benzophenone-based polymerization initiators, thioxanthone-based polymerization initiators, and acylphosphine-based polymerization initiators.

[17] The curable resin composition according to

[14] , wherein the polymerization initiator is a thermal and photo dual-use polymerization initiator selected from azo compound-based polymerization initiators and organic peroxides.

[18] The curable resin composition according to any one of [1] to

[17] , which contains a total of 0.1 to 15 parts by mass of any one or more of benzotriazole-based light stabilizers, triazine-based light stabilizers, cyanoacrylate-based light stabilizers, and hindered amine-based light stabilizers based on 100 parts by mass in total of the urethane (meth)acrylate (A) and the (meth)acrylate (B).

[19] A cured layer obtained by curing the curable resin composition according to any one of [1] to

[18] .

[20] An article having the cured layer according to

[19] on the entire surface, one surface, or a part of an inorganic or organic substrate.

[21] A method for forming a coating layer, which comprises applying the curable resin composition according to any one of [1] to

[18] onto a substrate, irradiating the curable resin composition with active energy rays, or heating the curable resin composition to cure the curable resin composition.

Advantages of the Invention

[0014] In the curable resin composition according to one embodiment of the present invention, the cured product obtained by curing on a resin substrate maintains adhesiveness and transparency even after being exposed to high-temperature conditions or high-temperature and high-humidity conditions for a long time.

[0015] Here, the definitions of the main terms used in this specification are provided. As used herein, the "hydroxyl value" refers to the number of milligrams of potassium hydroxide equivalent to the hydroxyl groups in 1 g of a sample, and is determined by esterifying the sample with a pyridine solution of phthalic anhydride and titrating the excess reagent with a potassium hydroxide solution in accordance with the polyether test method for polyurethanes described in Japanese Industrial Standard (JIS) K1557. Further, in the present specification, the "hydroxyl value" means the hydroxyl value as an average value. Therefore, for example, "(meth)acrylate having a hydroxyl value of 90 mg KOH / g" means a mixture of (meth)acrylates having the same or different hydroxyl values such that the average value of the hydroxyl value is 90 mg KOH / g. Also, as used herein, "polyhydric alcohol" means a compound having two or more functional hydroxyl groups, and "(meth)acrylate having a structure derived from a polyhydric alcohol" means a (meth)acrylate obtained by reacting a polyhydric alcohol with acrylic acid or methacrylic acid, etc., and having a part of the structure of the polyhydric alcohol. For example, pentaerythritol corresponds to "polyhydric alcohol", and in this case, "(meth)acrylate having a structure derived from a polyhydric alcohol" includes pentaerythritol mono(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate. On the other hand, for example, "lactone" does not correspond to "polyhydric alcohol", and "lactone-modified (meth)acrylate" does not correspond to "(meth)acrylate having a structure derived from a polyhydric alcohol". Also, as used herein, the term "(meth)acryl" is used in the sense of including both acrylic and methacrylic. Thus, for example, the term "(meth)acrylic acid" means both or either one of acrylic acid and methacrylic acid. Similarly, the term "(meth)acrylate" means both or either one of acrylate and methacrylate. In addition, the term "pentaerythritol (meth)acrylate" in this specification is used in a general sense to collectively refer to pentaerythritol mono(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate, and includes any one of these compounds or a mixture of two or more thereof. In addition, the term "dipentaerythritol (meth)acrylate" in this specification is used in a general sense to collectively refer to dipentaerythritol mono(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate, and includes any one of these compounds or a mixture of two or more thereof. The same applies to the term "tripentaerythritol (meth)acrylate". In addition, the term "glycerin (meth)acrylate" in this specification is used in a general sense to collectively refer to glycerin mono(meth)acrylate, glycerin di(meth)acrylate, and glycerin tri(meth)acrylate, and includes any one of these compounds or a mixture of two or more thereof. In addition, "polyvalent isocyanate" means a compound having two or more isocyanate groups in one molecule. In addition, the "isocyanate (NCO) content" in this specification refers to the value measured by a potentiometric measuring device in accordance with JIS K 1603-1 Method B. In addition, in the specification of the present application, "alkylene oxide-modified (meth)acrylate (B)" means a mixture of (meth)acrylates that contains at least alkylene oxide-modified (meth)acrylate and may optionally also contain alkylene oxide-unmodified (meth)acrylate. In addition, the "molecular weight" in this specification means the weight-average molecular weight, and in this specification, it refers to the value measured by gel permeation chromatography (GPC). Unless otherwise specified, "molecular weight" in this specification means weight average molecular weight (measured by GPC method using SHODEX KF-806M manufactured by Showa Denko). Also, "viscosity" in this specification refers to the value measured with a BM-type viscometer in accordance with JIS Z 8803. Unless otherwise specified, various operations and measurements of physical properties are carried out under the conditions of room temperature (20 - 25°C) / relative humidity 40 - 60%.

Embodiments for Carrying out the Invention

[0016] Embodiments of the present invention will be described below. However, the present invention is not limited by the following embodiments.

[0017] 1. Curable Resin Composition In one embodiment, the present invention relates to a curable resin composition containing a urethane (meth)acrylate (A) with a specific hydroxyl value and an alkylene oxide-modified (meth)acrylate (B).

[0018] 1-1. Urethane (meth)acrylate (A) Urethane (meth)acrylate (A) is obtained by the reaction of a (meth)acrylate (a1) with a hydroxyl value of 90 - 300 mgKOH / g, a polyisocyanate (a2), and optionally a low molecular weight polyol (a3). In the reaction of such a (meth)acrylate (a1) with a polyisocyanate (a2), the ratio of urethane bonds per molecule and the molecular weight of urethane (meth)acrylate (A) are within a certain range, and a cured product excellent in heat resistance and heat and humidity resistance can be obtained.

[0019] As the (meth)acrylate (a1) having a hydroxyl value of 90 to 300 mgKOH / g, a (meth)acrylate having a hydroxyl value of 90 to 300 mgKOH / g due to the structure derived from a polyhydric alcohol is preferred. Further, the structure derived from a polyhydric alcohol is not particularly limited, but a structure derived from at least one selected from the group consisting of glycerin, pentaerythritol, dipentaerythritol, and tripentaerythritol is preferred. In particular, a (meth)acrylate having either or both of the structures derived from dipentaerythritol and tripentaerythritol is preferred in terms of the moisture and heat resistance of the cured product.

[0020] Examples of the (meth)acrylate (a1) include glycerin (meth)acrylates such as glycerin mono(meth)acrylate, glycerin di(meth)acrylate, and glycerin tri(meth)acrylate; pentaerythritol (meth)acrylates such as pentaerythritol mono(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate; dipentaerythritol (meth)acrylates such as dipentaerythritol mono(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and dipentaerythritol penta(meth)acrylate; and tripentaerythritol (meth)acrylates such as tripentaerythritol mono(meth)acrylate, tripentaerythritol di(meth)acrylate, tripentaerythritol tri(meth)acrylate, tripentaerythritol tetra(meth)acrylate, tripentaerythritol penta(meth)acrylate, tripentaerythritol hexa(meth)acrylate, and tripentaerythritol hepta(meth)acrylate.

[0021] (Meth)acrylate (a1) is preferably a (meth)acrylate having a hydroxyl value of 90 to 180 mgKOH / g in terms of the moisture and heat resistance of the cured product, and more preferably a (meth)acrylate having a hydroxyl value of 100 to 150 mgKOH / g. On the other hand, in terms of the heat resistance of the cured product, a (meth)acrylate having a hydroxyl value of 200 to 300 mgKOH / g is preferred, and a (meth)acrylate having a hydroxyl value of 250 to 300 mgKOH / g is more preferred.

[0022] In (meth)acrylate (a1), the (meth)acrylate (mixture) having a desired hydroxyl value can be obtained, for example, as a mixture of the same or different (meth)acrylates, and determining the mixing ratio in consideration of the hydroxyl value of each compound. For example, when the (meth)acrylate (b1) having a hydroxyl value of 90 to 180 mgKOH / g is composed of pentaerythritol polyacrylate, for example, as a mixture of pentaerythritol triacrylate (hydroxyl value 188 mgKOH / g) containing one hydroxyl group and one or more of pentaerythritol monoacrylate, pentaerythritol diacrylate, and pentaerythritol tetraacrylate, a (meth)acrylate mixture containing pentaerythritol triacrylate in the range of 30 to 70% may be used. Also, when composed of glycerin polyacrylate, for example, as a mixture of glycerin diacrylate (hydroxyl value 280 mgKOH / g) containing one hydroxyl group and one or more of glycerin monoacrylate and glycerin triacrylate, a (meth)acrylate mixture containing glycerin diacrylate in the range of 20 to 55% may be used. In addition, when it is composed of dipentaerythritol polyacrylate, for example, a mixture of dipentaerythritol pentaacrylate containing one hydroxyl group (hydroxyl value: 106 mgKOH / g), dipentaerythritol tetraacrylate containing two hydroxyl groups (hydroxyl value: 238 mgKOH / g), and any one or more of dipentaerythritol monoacrylate, dipentaerythritol diacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate can be used. A (meth)acrylate mixture containing 5 to 85% of dipentaerythritol pentaacrylate and 5 to 75% of dipentaerythritol tetraacrylate may be used. In addition, when it is composed of tripentaerythritol polyacrylate, for example, a mixture of tripentaerythritol hexaacrylate containing two hydroxyl groups (hydroxyl value: 161 mgKOH / g), and any one or more of tripentaerythritol monoacrylate, tripentaerythritol diacrylate, tripentaerythritol triacrylate, tripentaerythritol tetraacrylate, tripentaerythritol pentaacrylate, tripentaerythritol heptaacrylate, and tripentaerythritol octaacrylate can be used. A (meth)acrylate mixture containing 5 to 55% of tripentaerythritol hexaacrylate may be used.

[0023] Similarly, when (meth)acrylate (b2) with a hydroxyl value of 200 to 300 mgKOH / g is composed of pentaerythritol polyacrylate, for example, a mixture of pentaerythritol diacrylate containing two hydroxyl groups (hydroxyl value: 459 mgKOH / g), and any one or more of pentaerythritol monoacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate can be used. A (meth)acrylate mixture containing 20 to 50% of pentaerythritol diacrylate may be used. When composed of glycerin polyacrylate, for example, it may be a mixture of glycerin diacrylate (hydroxyl value 280 mgKOH / g) containing one hydroxyl group, and one or more of glycerin monoacrylate and glycerin triacrylate, and an (meth)acrylate mixture containing glycerin diacrylate in the range of 50 to 80%. When composed of dipentaerythritol polyacrylate, for example, it may be a mixture of dipentaerythritol tetraacrylate (hydroxyl value 238 mgKOH / g) containing two hydroxyl groups, and one or more of dipentaerythritol monoacrylate, dipentaerythritol dicrolate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate, and an (meth)acrylate mixture containing dipentaerythritol tetraacrylate in the range of 50 to 85%. When composed of tripentaerythritol polyacrylate, for example, it may be a mixture of tripentaerythritol pentaacrylate (hydroxyl value 262 mgKOH / g) containing two hydroxyl groups, and one or more of tripentaerythritol monoacrylate, tripentaerythritol diacrylate, tripentaerythritol triacrylate, tripentaerythritol tetraacrylate, tripentaerythritol hexaacrylate, tripentaerythritol heptaacrylate, and tripentaerythritol octaacrylate, and an (meth)acrylate mixture containing tripentaerythritol pentaacrylate in the range of 40 to 85%.

[0024] There are no particular restrictions on the polyvalent isocyanate (a2). Examples include aliphatic, alicyclic or aromatic isocyanates and polyisocyanates, and their hydrogenated products. In terms of obtaining a cured product with high resistance to wet heat, aliphatic isocyanates, alicyclic isocyanates without a crosslinked structure, aromatic isocyanates or their hydrogenated products are preferred, and alicyclic isocyanates without a crosslinked structure are particularly preferred.

[0025] Examples of the polyvalent isocyanate (a2) include isophorone diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, polymeric MDI, tetramethylxylylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate methyl ester, methylene bis(4,1-cyclohexylene)-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, tolylene diisocyanate (e.g., 2,4-tolylene diisocyanate), phenylene diisocyanate (1,4-phenylene diisocyanate), diphenyl diisocyanate (e.g., 4,4-diphenyl diisocyanate, 3,3-dimethyl-4,4-diphenylene diisocyanate), diphenylmethane diisocyanate (4,4-diphenylmethane diisocyanate), naphthalene diisocyanate (e.g., 1,5-naphthalene diisocyanate), xylylene diisocyanate, an adduct of a diisocyanate compound and a polyol compound such as trimethylolpropane, and isocyanate derivatives such as a biuret body or an isocyanurate body of a diisocyanate compound. Among them, from the viewpoint of improving the moisture and heat resistance of the cured product, 1,3-bis(isocyanatomethyl)cyclohexane, isophorone diisocyanate, or dicyclohexylmethane diisocyanate is preferable, and dicyclohexylmethane diisocyanate is more preferable. As commercially available products, VESTANAT (registered trademark) IPDI manufactured by Evonik, VESTANAT (registered trademark) H12MDI manufactured by Evonik, Duranate D-201, TPA-100, TKA-100, 24A-100, 22A-75P, P301-75E, etc. manufactured by Asahi Kasei Corporation, Coronate HX, 2715, etc. manufactured by Toray Industries, Inc., HDI manufactured by Toray Industries, Inc., Takenate (registered trademark) D160N, D-170N, D-170HN, D-172N, D-177N, 600, etc. manufactured by Mitsui Chemicals, Inc. can be used. These may be used alone or in combination of two or more.

[0026] The urethane (meth)acrylate (A) may be synthesized by reacting with the (meth)acrylate (a1) and the polyisocyanate (a2), and optionally adding a polyol (a3). The polyol preferably has a solubility in water at 25 °C of 3.0 g / L or more, more preferably 3.5 g / L or more, even more preferably 4.0 g / L or more, and particularly preferably one that can dissolve in water in any ratio. Examples of the polyol include dihydric alcohols, trihydric alcohols, and condensates thereof. Specifically, alkylene glycols such as ethylene glycol, propylene glycol, 1,3-propanediol, and 1,3-butanediol; polyalkylene glycols such as diethylene glycol, dipropylene glycol, polyethylene glycol, and polypropylene glycol; glycerin and glycerin condensates such as glycerin, diglycerin, and triglycerin; and triols such as 1,2,4-butanetriol, 1,2,5-pentanetriol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, and trimethylolpropane. The average molecular weight of polyalkylene glycols such as polyethylene glycol and polypropylene glycol is preferably 2000 or less, more preferably 1000 or less, and even more preferably 400 or less. Among the above polyols, ethylene glycol, propylene glycol, 1,3-butanediol, dipropylene glycol, polyethylene glycol (molecular weight 400 or less), glycerin, and diglycerin are more preferred, and propylene glycol, 1,3-butanediol, dipropylene glycol, polyethylene glycol (molecular weight 400 or less), and glycerin are even more preferred. Also, a polyol with a low molecular weight (specifically, a molecular weight of 100 or less, preferably a molecular weight of 50 to 100) is preferred in that it has a small impact on the heat resistance and the hardness under humid heat of the cured product. The content of the low molecular weight polyol (a3) in the reaction composition usually may be in the range of 0 to 10.

[0027] (Meth)acrylate (a1) and polyisocyanate (a2) can react with high efficiency, and by reducing the residual hydroxyl groups in the resulting urethane (meth)acrylate (A), the heat resistance and heat and moisture resistance of the cured product can be significantly improved. From this perspective, (meth)acrylate (a1) with a hydroxyl value of 90 to 300 mgKOH / g, polyisocyanate (a2), and polyol (a3) are preferably mixed in a ratio (molar number of isocyanate groups / total molar number of hydroxyl groups) of 0.95 to 1.05, which is determined by the following formulas (1) and (2). Total molar number of hydroxyl groups = ((amount of (a1) formulated) / hydroxyl equivalent of (a1)) + ((amount of (a3) formulated) / hydroxyl equivalent of (a3)) ··· (1) (In the formula, the hydroxyl equivalent means molecular weight / number of hydroxyl groups.) Molar number of isocyanate groups = (amount of (a2) formulated) / isocyanate equivalent of (a2) ··· (2) (In the formula, the isocyanate equivalent of (a2) means molecular weight / number of isocyanate groups.)

[0028] (Meth)acrylate (a1), polyisocyanate (a2), and optionally low-molecular polyol (a3) can be reacted under the conditions of a normal urethanization reaction. For example, after dissolving these compounds in an organic solvent, a catalyst, a polymerization inhibitor, etc. can be appropriately added, and the reaction can be carried out by heating.

[0029] Examples of organic solvents include aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; esters or ether esters such as ethyl acetate, butyl acetate, and methoxybutyl acetate; ethers such as diethyl ether, tetrahydrofuran, monoethyl ether of ethylene glycol, monobutyl ether of ethylene glycol, monomethyl ether of propylene glycol, and monoethyl ether of diethylene glycol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, and cyclohexanone; amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; and sulfoxides such as dimethyl sulfoxide.

[0030] Examples of catalysts include inorganic bismuth; organotin compounds such as dioctyltin, dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, tributyltin acetate, triethyltin ethoxide, tributyltin ethoxide, dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate; and tertiary amine compounds such as triethylamine, triethylenediamine, and 1,8-diazabicyclo(5,4,0)-undecene-7 (DBU). Among them, inorganic bismuth is particularly preferred because it does not contain tin.

[0031] From the perspective of preventing the C=C bond from reacting and gelling, a polymerization inhibitor may be added. For example, polymerization inhibitors such as phenothiazine, tri-p-nitrophenylmethyl, di-p-fluorophenylamine, diphenylpicrylhydrazyl, N-(3-N-oxyaniolino-1,3-dimethylbutylidene) aniline oxide, benzoquinone, hydroquinone, methoquinone, butylcatechol, nitroso benzene, picric acid, dithiobenzoyl disulfide, cupferron, copper(II) chloride, etc. can be used. From the perspective of the polymerization inhibition effect, methoquinone is preferred. These polymerization inhibitors may be used alone or in combination of two or more. The reaction temperature varies depending on the catalyst, but usually, it may be carried out at 50 to 120 °C.

[0032] The obtained urethane (meth) acrylate (A) has a small residual hydroxyl value, so that a urethane (meth) acrylate with a higher functional group number and molecular weight can be obtained. Also, by reducing the hydrophilic residual hydroxyl groups, the heat resistance and heat and humidity resistance of the cured product can be significantly improved. Therefore, it is preferable that the urethane (meth) acrylate (A) has a small residual hydroxyl group. Specifically, the hydroxyl value is preferably 15 mgKOH / g or less, more preferably 0.1 to 10 mgKOH / g of urethane (meth) acrylate (A), and particularly preferably 0.1 to 7 mgKOH / g of urethane (meth) acrylate (A).

[0033] Also, from the perspective of the adhesion of the cured product under high temperature and high heat and humidity conditions, the molecular weight of the urethane (meth) acrylate (A2) is preferably 2,000 to 20,000, and more preferably 3,000 to 18,000. Also, from the perspective of compatibility with the urethane (meth) acrylate (A1), as well as adhesion and transparency under high heat and humidity conditions, the molecular weight of the urethane (meth) acrylate (A1) is preferably 1,000 to 5,000, and more preferably 1,200 to 4,000.

[0034] In a preferred embodiment, the coating agent contains a mixture of urethane (meth)acrylate (A1) and urethane (meth)acrylate (A2). U Since urethane (meth)acrylate (A2) can reduce the curing shrinkage of the coating film, it has excellent adhesion at high temperatures of the cured product. and Other side, U Urethane (meth)acrylate (A1) improves the crosslink density of the cured coating film, preventing the penetration of moisture into the cured product and the substrate interface, and preventing the deterioration of adhesion and transparency under high humidity and high temperature conditions. By combining such urethane (meth)acrylates, a cured product excellent in adhesion and transparency can be obtained under high temperature and high humidity and high temperature conditions. The mass ratio (A / B) of urethane (meth)acrylate (A1) to urethane (meth)acrylate (A2) is not particularly limited, and for example, they can be combined in the range of 1 / 5 to 9 / 1, preferably 1 / 3 to 8 / 1 is more preferable, 1 / 2 to 7 / 1 is more preferable, and 1 / 1 to 5 / 1 is particularly preferable.

[0035] The content of urethane (meth)acrylate (A) in the coating agent can vary within a relatively wide range. Usually, the coating film component in the coating agent can contain urethane (meth)acrylate (A) in the range of 5 to 95% by mass, preferably 10 to 90% by mass, more preferably 20 to 80% by mass, and particularly preferably 40 to 70% by mass.

[0036] 1-2. Alkylene oxide-modified (meth)acrylate (B) A curable resin composition according to one embodiment of the present invention contains an alkylene oxide-modified (meth)acrylate (B) together with the above-mentioned urethane (meth)acrylate (A). The alkylene oxide-modified (meth)acrylate (B) contains a (meth)acrylate (B1) having an average number of alkylene oxide repeating units of 0 to 2.0, and optionally a (meth)acrylate (B2) having an average number of alkylene oxide repeating units of 3.0 to 5.0, and a (meth)acrylate (B3) having an average number of alkylene oxide repeating units of 6.0 to 8.0. It is not clear why the use of (meth)acrylates with alkylene oxide addition numbers within these specific ranges results in good heat-resistant adhesion, moist heat-resistant adhesion, and moist heat-resistant transparency, but it is thought that (meth)acrylates with fewer alkylene oxide addition numbers penetrate into the substrate and improve adhesion durability through an anchoring effect, while (meth)acrylates with more alkylene oxide addition numbers improve adhesion by reducing the internal stress of the cured material after curing with active energy rays.

[0037] The (meth)acrylate (B) is preferably represented by the following formula (1): [ka] It is a mixture of (meth)acrylates represented by the formula: In the formula, R1 is hydrogen or a methyl group. In addition, in the formula, A is a trimethylolpropane residue, a bisphenol A residue, or a pentaerythritol residue, and is preferably a trimethylolpropane residue. In addition, in the formula, m is an integer of 2 to 3, and is preferably 2. In addition, in the formula, n is an integer of 0 to 8, and is preferably an integer of 0 to 7.

[0038] The alkylene oxide-modified (meth)acrylate (B) is preferably an alkylene oxide (preferably C 2-3Alkylene oxide-modified dipentaerythritol hexa(meth)acrylate, dipentaerythritol hexa(meth)acrylate, alkylene oxide (preferably C 2-3 Alkylene oxide-modified pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, alkylene oxide (preferably C 2-3 Alkylene oxide-modified trimethylolpropane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, alkylene oxide (preferably C 2-3 Alkylene oxide-modified glyceryl tri(meth)acrylate, glyceryl tri(meth)acrylate, alkylene oxide (preferably C 2-3 Alkylene oxide-modified bisphenol A di(meth)acrylate, bisphenol A di(meth)acrylate are exemplified. Among them, those having about 2 to 3 (meth)acrylate groups are preferable in terms of improving water resistance without deteriorating adhesion due to curing shrinkage. Particularly, trimethylolpropane tri(meth)acrylate and its alkylene oxide (preferably C 2-3 Alkylene oxide) modification product, bisphenol A di(meth)acrylate and its alkylene oxide (preferably C 2-3 Alkylene oxide) modification product are more preferable.

[0039] (Meth)acrylate (B1) is selected from the above-mentioned (meth)acrylates (B) such that the average number of repeating units of alkylene oxide is 0 to 2.0. (Meth)acrylate (B1) is preferably bisphenol A di(meth)acrylate, ethylene oxide (1 mol) - added bisphenol A di(meth)acrylate, ethylene oxide (2 mol) - added bisphenol A di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide (1 mol) - added trimethylolpropane tri(meth)acrylate, ethylene oxide (2 mol) - added trimethylolpropane tri(meth)acrylate, pentaerythritol tri- and tetra(meth)acrylate, ethylene oxide (1 mol) - added pentaerythritol tri- and tetra(meth)acrylate, ethylene oxide (2 mol) - added pentaerythritol tri- and tetra(meth)acrylate, glycerin tri(meth)acrylate, ethylene oxide (1 mol) - added glycerin tri(meth)acrylate, ethylene oxide (2 mol) - added glycerin tri(meth)acrylate. Among them, bisphenol A di(meth)acrylate and its ethylene oxide adducts, and trimethylolpropane tri(meth)acrylate and its ethylene oxide adducts are particularly preferred in terms of excellent heat resistance adhesion and moisture heat resistance adhesion.

[0040] (Meth)acrylate (B2) is selected from the above-mentioned (meth)acrylates (B) such that the average number of repeating units of alkylene oxide is 3.0 to 5.0. (Meth)acrylate (B2) is preferably bisphenol A di(meth)acrylate with 3 mol of ethylene oxide added, bisphenol A di(meth)acrylate with 4 mol of ethylene oxide added, bisphenol A di(meth)acrylate with 5 mol of ethylene oxide added, glycerin tri(meth)acrylate with 3 mol of ethylene oxide added, glycerin tri(meth)acrylate with 4 mol of ethylene oxide added, glycerin tri(meth)acrylate with 5 mol of ethylene oxide added, trimethylolpropane tri(meth)acrylate with 3 mol of ethylene oxide added, trimethylolpropane tri(meth)acrylate with 4 mol of ethylene oxide added, trimethylolpropane tri(meth)acrylate with 5 mol of ethylene oxide added, pentaerythritol tri- and tetra(meth)acrylate with 3 mol of ethylene oxide added, pentaerythritol tri- and tetra(meth)acrylate with 4 mol of ethylene oxide added, pentaerythritol tri- and tetra(meth)acrylate with 5 mol of ethylene oxide added, dipentaerythritol hexaacrylate with 3 mol of ethylene oxide added, dipentaerythritol hexaacrylate with 4 mol of ethylene oxide added, dipentaerythritol hexaacrylate with 5 mol of ethylene oxide added. Among them, bisphenol A di(meth)acrylate and its ethylene oxide adducts, and trimethylolpropane tri(meth)acrylate and its ethylene oxide adducts are particularly preferred in terms of excellent heat and moisture-resistant adhesiveness.

[0041] (Meth)acrylate (B3) is selected from the above-mentioned (meth)acrylates (B) such that the average number of repeating units of alkylene oxide is 6.0 to 8.0. (Meth)acrylate (B3) is preferably bisphenol A di(meth)acrylate with 6 mol of ethylene oxide added, bisphenol A di(meth)acrylate with 7 mol of ethylene oxide added, bisphenol A di(meth)acrylate with 8 mol of ethylene oxide added, glycerin tri(meth)acrylate with 6 mol of ethylene oxide added, glycerin tri(meth)acrylate with 7 mol of ethylene oxide added, glycerin tri(meth)acrylate with 8 mol of ethylene oxide added, trimethylolpropane tri(meth)acrylate with 6 mol of ethylene oxide added, trimethylolpropane tri(meth)acrylate with 7 mol of ethylene oxide added, trimethylolpropane tri(meth)acrylate with 8 mol of ethylene oxide added, pentaerythritol tri- and tetra(meth)acrylate with 6 mol of ethylene oxide added, pentaerythritol tri- and tetra(meth)acrylate with 7 mol of ethylene oxide added, pentaerythritol tri- and tetra(meth)acrylate with 8 mol of ethylene oxide added, dipentaerythritol hexaacrylate with 6 mol of ethylene oxide added, dipentaerythritol hexaacrylate with 7 mol of ethylene oxide added, dipentaerythritol hexaacrylate with 8 mol of ethylene oxide added. Among them, bisphenol A di(meth)acrylate and its ethylene oxide adducts, and trimethylolpropane tri(meth)acrylate and its ethylene oxide adducts are particularly preferred in terms of excellent heat and moisture-resistant adhesiveness.

[0042] The alkylene oxide-modified (meth)acrylate (B) is preferably a mixture containing a (meth)acrylate (B1) having an average alkylene oxide repeating unit number (n in formula (1)) of 0 to 2.0, a (meth)acrylate (B2) having an average alkylene oxide repeating unit number (n in formula (1)) of 3.0 to 5.0, and a (meth)acrylate (B3) having an average alkylene oxide repeating unit number (n in formula (1)) of 6.0 to 8.0 in order to improve both heat resistance and heat and humidity resistance properties.

[0043] In terms of improving both heat resistance and heat and humidity resistance properties, the alkylene oxide-modified (meth)acrylate (B) preferably contains 5 to 50% by mass of (meth)acrylate (B1), 20 to 90% by mass of (meth)acrylate (B2), and 5 to 30% by mass of (meth)acrylate (B3). More preferably, the alkylene oxide-modified (meth)acrylate (B) contains 10 to 45% by mass of (meth)acrylate (B1), 30 to 80% by mass of (meth)acrylate (B2) with n in formula (1) being 3.0 to 5.0, and 10 to 25% by mass of (meth)acrylate (B3) with n in formula (1) being 6.0 to 8.0.

[0044] There is no particular limitation on the content of (meth)acrylate (B) in the coating agent, and it can vary widely. Usually, the coating film component of the coating agent can contain (meth)acrylate (B) in the range of 5 to 95% by mass, preferably contain (meth)acrylate (B) in the range of 10 to 90% by mass, more preferably contain (meth)acrylate (B) in the range of 20 to 80% by mass, and particularly preferably contain (meth)acrylate (B) in the range of 40 to 70% by mass. 1-3. Other components

[0045] The curable resin composition may contain other components such as a polymerization initiator, a light stabilizer, a solvent, a thickener, a flame retardant, an ultraviolet absorber, a leveling agent, and an antioxidant as necessary.

[0046] As the polymerization initiator, either a thermal polymerization initiator or a photoinitiator may be used according to the polymerization method. Examples of the thermal polymerization initiator include azo compound-based polymerization initiators, organic peroxide-based polymerization initiators, and inorganic peroxide-based polymerization initiators. Azo compound-based polymerization initiators and organic peroxide-based polymerization initiators are preferred, and organic peroxide-based polymerization initiators are more preferred. Examples of the photopolymerization initiator include acetophenone-based polymerization initiators, benzophenone-based polymerization initiators, alkylphenone-based polymerization initiators, thioxanthone-based polymerization initiators, xanthone-based photopolymerization initiators, acylphosphine-based polymerization initiators, oxime-based polymerization initiators, benzoin compound-based polymerization initiators, anthracene compound-based polymerization initiators, and quinone compound-based polymerization initiators. Acetophenone-based polymerization initiators, benzophenone-based polymerization initiators, thioxanthone-based polymerization initiators, and acylphosphine-based polymerization initiators are preferred. Examples of the thermal and photopolymerization initiators include azo compound-based polymerization initiators and organic peroxides. These polymerization initiators can be used alone or in combination of two or more. For example, combinations of an acetophenone-based photopolymerization initiator and a benzophenone-based photopolymerization initiator, and combinations of an acetophenone-based photopolymerization initiator and a thioxanthone-based photopolymerization initiator are preferred.

[0047] Examples of azo compound-based thermal polymerization initiators include 2,2-azobisisobutyronitrile (AIBN), 2,2'-azobis(2-methylbutyronitrile) (AMBN), azobiscyanovaleric acid, 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2'-azobis(2-methylpropionate), 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide], 2,2'-azobis(N-butyl-2-methylpropionamide), 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] disulfate dihydrate, 2,2'-azobis(2-methylpropionamidine) dihydrochloride, 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] hydrate, 2,2'-azobis[2-(2-imidazolin-2-yl)propane], 2,2'-azobis(1-imino-1-pyrrolidino-2-methylpropane) dihydrochloride, 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide], etc. These may be used alone or in combination of two or more. Among them, 2,2-azobisisobutyronitrile (AIBN) is preferred.

[0048] Examples of organic peroxide-based polymerization initiators include organic peroxides such as tert-butyl peroxypivalate, tert-butyl peroxybenzoate, tert-butyl peroxy-2-ethylhexanoate, di-tert-butyl peroxide, cumene hydroperoxide, benzoyl peroxide, tert-butyl hydroperoxide, etc. These may be used alone or in combination of two or more. Examples of inorganic peroxide-based polymerization initiators include inorganic peroxides such as hydrogen peroxide, ammonium persulfate, potassium persulfate, sodium persulfate, etc. These may be used alone or in combination of two or more. Among them, benzoyl peroxide is preferred.

[0049] Examples of acetophenone-based photoinitiators include α-aminoacetophenone-based photoinitiators such as 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, and α-hydroxyacetophenone-based photoinitiators such as 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, and 2-hydroxy-1-[4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl]-2-methyl-propan-1-one. These may be used alone or in combination of two or more. Among them, α-hydroxyacetophenone-based photoinitiators are preferred.

[0050] Examples of benzophenone-based polymerization initiators include benzophenone, 4-methylbenzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylated benzophenone, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-propoxybenzophenone, benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzophenone, 4,4'-di(N,N'-dimethylamino)-benzophenone, etc. These may be used alone or in combination of two or more. Among them, benzophenone is preferred.

[0051] Examples of alkylphenone compound-based polymerization initiators include benzyl methyl ketal compounds such as 2,2'-dimethoxy-1,2-diphenylethane-1-one, α-hydroxyalkylphenone compounds such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one, and aminoalkylphenone compounds such as 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzylmethyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, etc. These may be used alone or in combination of two or more.

[0052] Examples of thioxanthone-based photoinitiators include thioxanthone, dimethylthioxanthone (e.g., 2,4-dimethylthioxanthone), diethylthioxanthone (e.g., 2,4-diethylthioxanthone), isopropylthioxanthone (e.g., 2-isopropylthioxanthone), chlorothioxanthone (e.g., 2,4-dichlorothioxanthone), mercaptothioxanthone, and the like. Examples of xanthone-based photoinitiators include xanthone, 2-isopropylxanthone, 2,4-dimethylxanthone, 2,4-diethylxanthone, 2,4-dichloroxanthone, and the like. These may be used alone or in combination of two or more.

[0053] Examples of acylphosphine-based photoinitiators include bisacylphosphine oxide-based photoinitiators and monoacylphosphine oxide-based photoinitiators. Specifically, for example, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, methyl 2,4,6-trimethylbenzoylphenylphosphinate, 2-methylbenzoyldiphenylphosphine oxide, isopropyl pivaloylphenylphosphinate, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphinate, (2,6-dimethoxybenzoyl)-2,4,4-pentylphosphine oxide, etc. These may be used alone or in combination of two or more. In particular, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide is preferred.

[0054] Examples of the O-acyl oxime compound-based photoinitiator include N-benzoyloxy-1-(4-phenylsulfanylphenyl)butan-1-one-2-imine, N-benzoyloxy-1-(4-phenylsulfanylphenyl)octan-1-one-2-imine, N-benzoyloxy-1-(4-phenylsulfanylphenyl)-3-cyclopentylpropan-1-one-2-imine, N-acetoxy-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethan-1-imine, N-acetoxy-1-[9-ethyl-6-{2-methyl-4-(3,3-dimethyl-2,4-dioxacyclopentanylmethyloxy)benzoyl}-9H-carbazol-3-yl]ethan-1-imine, N-acetoxy-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-3-cyclopentylpropan-1-imine, N-benzoyloxy-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-3-cyclopentylpropan-1-one-2-imine, N-acetoxy-1-[4-(2-hydroxyethyloxy)phenylsulfanylphenyl]propan-1-one-2-imine, N-acetoxy-1-[4-(1-methyl-2-methoxyethoxy)-2-methylphenyl]-1-(9-ethyl-6-nitro-9H-carbazol-3-yl)methan-1-imine, and the like.

[0055] Examples of the benzoin compound-based polymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and the like.

[0056] Examples of the anthracene compound-based polymerization initiator include 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 2-ethyl-9,10-diethoxyanthracene, and the like. Examples of the quinone compound-based polymerization initiator include 9,10-phenanthrenequinone, 2-ethylanthraquinone, and camphorquinone.

[0057] The content of the polymerization initiator is preferably 0.01 to 10 parts by mass, more preferably 2 to 8 parts by mass, based on 100 parts by mass in total of the components (A) and (B). When combining a plurality of polymerization initiators, the total content thereof may be adjusted so as to satisfy the above mass ratio. For example, in the case of a combination of an acetophenone-based photoinitiator and a benzophenone-based photoinitiator, or a combination of an acetophenone-based photoinitiator and a thioxanthone-based photoinitiator, the mass ratio of the acetophenone-based photoinitiator to the benzophenone-based photoinitiator or the thioxanthone-based photoinitiator is preferably 3:1 to 1:2, more preferably 2:1 to 1:1.

[0058] There is no particular limitation on the ultraviolet absorber. For example, benzotriazole-based ultraviolet absorbers, triazine-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers can be mentioned. These may be used alone or in combination of two or more.

[0059] Examples of benzotriazole-based ultraviolet absorbers include 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)benzotriazole, 2-(3,5-di-t-pentyl-2-hydroxyphenyl)-2-benzotriazole, 2-(2-benzotriazol-2-yl)-4-methyl-6-(3,4,5,6-tetrahydrophthalimidylmethyl)phenol, 2-(2-hydroxy-4-octyloxyphenyl)-2-benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)-2-benzotriazole, 2-(2-hydroxy-5-methyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2-(2-hydroxy-5-t-butylphenyl)benzotriazole, 2-(2-hydroxy-3-t-butyl-5-methylphenyl)benzotriazole, 2-(2-hydroxy-3,5-t-butylphenyl)benzotriazole, 2-(2-hydroxy-3,5-t-butylphenyl)-5-chlorobenzotriazole, 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol, 2-(2-hydroxy-3,5-t-pentylbenzotriazole, 2-[2-hydroxy-5-(1,1,3,3,-tetramethylbutyl)]benzotriazole, 2-(2-hydroxy-3-s-butyl-5-t-butylbenzotriazole, 2-(2-hydroxy-3-dodecyl-5-methylbenzotriazole, 2-(2-hydroxy-3-t-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2,2-methylenebis[4-(1,1,3,3-tetramethylbutyl)]-6-(2H-benzotriazol-2-yl)phenol], and 3-[3-(2H-benzotriazol-2-yl)-5-t-butyl-4-hydroxyphenyl]propionate, etc.

[0060] Examples of triazine-based ultraviolet absorbers include 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-methoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-ethoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-(2-hydroxy-4-propoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-hexyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-dodecyloxyphenyl)-1,3,5-triazine, and 2,4-diphenyl-6-(2-hydroxy-4-benzyloxyphenyl)-1,3,5-triazine, etc.

[0061] Examples of cyanoacrylate-based ultraviolet absorbers include 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate, ethyl-2-cyano-3,3'-diphenylacrylate, etc.

[0062] The ultraviolet absorber is preferably contained in the curable resin composition in the range of 0 to 2.0% by mass, more preferably in the range of 0.1 to 1.0% by mass. Further, the ultraviolet absorber is preferably contained in the range of 0 to 20 parts by mass, preferably in the range of 5 to 16 parts by mass, and preferably in the range of 8 to 14 parts by mass, based on 100 parts by mass in total of urethane (meth)acrylate (A) and alkylene oxide-modified (meth)acrylate (B).

[0063] There is no particular limitation on the light stabilizer, and for example, hindered amine light stabilizers can be mentioned.

[0064] Examples of hindered amine light stabilizers include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis(1-methoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-ethoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-propoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-butoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-pentyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-hexyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-heptyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-nonyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-decanyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1-dodecyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)-2-(4-methoxy-benzylidene) malonate, tetrakis(2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate and other aminomethyl group-containing compounds, the condensate of 1,2,3,4-butanetetracarboxylic acid with 1,2,2,6,6-pentamethyl-4-piperidinol and β,β,β,β-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5])undecane)diethanol, the condensate of 1,2,3,4-butanetetracarboxylic acid with 2,2,6,6-pentamethyl-4-piperidinol and β,β,β,β-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5])undecane)diethanol, the diester compound of decanedicarboxylic acid with 2,2,6,6-tetramethyl-1-octyloxy-4-piperidinol and 1,Reaction products of 1-dimethylethyl hydroperoxide and octane (manufactured by BASF, trade name Tinuvin 123), amino ether group-containing compounds such as bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl] (manufactured by BASF, trade name Tinuvin 144), etc. are included.

[0065] The light stabilizer is preferably contained in the curable resin composition in the range of 0 to 0.3% by mass, more preferably in the range of 0.05 to 0.2% by mass. Further, the light stabilizer is preferably contained in the total of 0 to 2.5 parts by mass in the range of 0 to 2.5 parts by mass with respect to 100 parts by mass of the total of urethane (meth)acrylate (A) and alkylene oxide-modified (meth)acrylate (B), preferably in the range of 0.6 to 2 parts by mass, and preferably in the range of 1 to 1.8 parts by mass. Also, it is preferable to combine the light stabilizer with the above-described ultraviolet absorber. In this case, the mass ratio of the ultraviolet absorber to the stabilizer (ultraviolet absorber: stabilizer) is preferably in the range of 1:2 to 30:1, and more preferably in the range of 1:1 to 14:1.

[0066] Examples of the leveling agent include silicone-based leveling agents such as polydimethylsiloxane, its copolymer, acrylic polymers having a polydimethylsiloxane skeleton, urethane polymers having a polydimethylsiloxane skeleton, and compounds obtained by introducing acryloyl groups or methacryloyl groups into these to impart active energy ray reactivity, or fluorine-based leveling agents such as perfluoroalkyl sulfonic acid, perfluoroalkyl carboxylic acid, fluorine telomer alcohol or their derivatives. Examples of commercially available products include Fagent 602A manufactured by Neo's Co., Ltd. The leveling agent is preferably contained in the coating agent of the present invention in the range of 0 to 0.5% by mass, more preferably in the range of 0.01 to 0.3% by mass.

[0067] Examples of the antioxidant include di-t-butylhydroxytoluene, 2,4-bis(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1,3,5-triazine, pentaerythrityl tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2'-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, N,N-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tris(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, octylated diphenylamine, 2,4-bis[(octylthio)methyl]-o-cresol, isooctyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, dibutylhydroxytoluene, and the like. The antioxidant is preferably contained in the coating agent of the present invention in the range of 0 to 2% by mass.

[0068] Examples of the thickener include associative nonionic urethane thickeners, alkali-swellable thickeners, bentonite which is an inorganic intercalation compound, cellulose thickeners, (meth)acrylic acid thickeners, polyurethane thickeners, polyacrylamide thickeners, vinyl ether thickeners, mineral thickeners, polysaccharide thickeners, and the like. The thickener is preferably contained in the curable resin composition of the present invention in the range of 0 to 5% by mass.

[0069] Examples of the plasticizer include phthalic acid esters, non-aromatic dibasic acid esters, aliphatic esters, esters of polyalkylene glycols, phosphoric acid esters, trimellitic acid esters, chlorinated paraffins, hydrocarbon oils, process oils, polyethers, epoxy plasticizers, polyester plasticizers, etc., and phthalic acid esters are preferred. Specific examples of the plasticizer include dibutyl phthalate, diheptyl phthalate, di(2-ethylhexyl) phthalate, dioctyl phthalate, dioctyl adipate, dioctyl sebacate, dibutyl sebacate, isodecyl succinate, tricresyl phosphate, tributyl phosphate, epoxidized soybean oil, benzyl epoxy stearate, etc. The plasticizer is preferably contained in the curable resin composition of the present invention in the range of 0 to 10% by mass.

[0070] Examples of the lubricant include hydrocarbon-based, fatty acid-based, higher alcohol-based, aliphatic amide-based, metal soap-based, ester-based, amide-based lubricants, silicone compounds, perfluoroalkyl compounds, etc. The lubricant is preferably contained in the curable resin composition of the present invention in the range of 0 to 1% by mass.

[0071] Examples of the colorant include dyes such as direct dyes, acid dyes, basic dyes, metal complex dyes; inorganic pigments such as carbon black, titanium oxide, zinc oxide, iron oxide, mica; and organic pigments such as coupling azo-based, condensed azo-based, anthraquinone-based, thioindigo-based, dioxazone-based, phthalocyanine-based pigments. The colorant is preferably contained in the curable resin composition of the present invention in the range of 0 to 2% by mass.

[0072] Examples of the flame retardant include addition and reaction type flame retardants such as phosphorus and halogen-containing organic compounds, bromine or chlorine-containing organic compounds, ammonium polyphosphate, aluminum hydroxide, antimony oxide, etc. The flame retardant is preferably contained in the curable resin composition of the present invention in the range of 0 to 20% by mass.

[0073] Examples of the antistatic agent include at least one anionic antistatic agent selected from cationic antistatic agents of quaternary ammonium salts, aliphatic sulfonates, higher alcohol sulfates, higher alcohol alkylene oxide adduct sulfates, higher alcohol phosphates, and higher alcohol alkylene oxide adduct phosphates, higher alcohol alkylene oxide adducts, polyalkylene glycol fatty acid esters, and the like. The antistatic agent is preferably contained in the curable resin composition of the present invention in the range of 0 to 5% by mass.

[0074] Examples of the organic particles include particles formed from polyacrylate resins, polymethacrylate resins, polyolefin resins, polystyrene resins, polyamide resins, polyamino acid resins, polyester resins, polyurethane resins, polyvinyl chloride resins, cellulose resins, melamine resins, urea resins, epoxy resins, fluororesins, and mixtures thereof. The organic particles are preferably contained in the curable resin composition of the present invention in the range of 0 to 30% by mass.

[0075] The coating agent of the present invention contains each of the above-described components in a polymerization solvent. The polymerization solvent is not particularly limited as long as it can dissolve each monomer to be polymerized, the resulting polymer precursor, and, if necessary, a polymerization initiator and other additives. Methanol, ethanol, isopropanol, tetrahydrofuran, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, diethylene glycol dimethyl ether, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, N,N-dimethylformamide, N,N-dimethylacetamide, toluene, ethyl acetate, ethyl lactate, methyl lactate, dimethyl sulfoxide, water, etc. can be used. These may be used alone or in combination of two or more. 1-Methoxy-2-propanol (PGM) is preferred in terms of having appropriate solubility and being difficult to dissolve a substrate such as polycarbonate.

[0076] There is no particular limitation on the content of the polymerization solvent in the curable composition, but usually, 10% by mass to 80% by mass of the polymerization solvent can be blended in the curable composition. In many cases, 30% by mass to 70% by mass of the polymerization solvent, preferably 30% by mass to 60% by mass of the polymerization solvent, is blended in the curable composition. Also, it is usually 10 parts by mass to 500 parts by mass, preferably 50 parts by mass to 300 parts by mass, based on 100 parts by mass of the organic coating component. The viscosity of the coating agent is usually 5 to 500 mPa·s, preferably 10 to 100 mPa·s, at the temperature during use (usually 15 to 30°C). The coating agent may be diluted with a solvent to adjust to an appropriate viscosity during coating. The content of the solvent after dilution is usually 55 to 85% by mass in the coating agent, preferably 70 to 80% by mass.

[0077] The curable composition can form a cured product on the entire surface, one side, or a part of an inorganic or organic substrate, for example, by applying it on the substrate and irradiating the curable composition with active energy rays or by heating. For curing, both irradiation with active energy rays and heating may be performed.

[0078] The curable composition can be applied on the substrate by, for example, a bar coater, an applicator, a die coater, a spin coater, a spray coater, a curtain coater, a roll coater, screen printing, dipping, etc.

[0079] The coating amount of the curable composition on the substrate is not particularly limited and may be adjusted according to the thickness of the cured layer to be formed. As a guide, the amount that results in a cured layer thickness of 1 to 1,000 μm after curing treatment by irradiation with active energy rays and / or heating is preferable, and the amount that results in a cured layer thickness of 10 to 800 μm is more preferable.

[0080] There is no particular limitation on the active energy rays either, and examples include ultraviolet rays, electron beams, etc. When irradiating with ultraviolet rays, an ultraviolet irradiation device equipped with a light source such as a high-pressure mercury lamp or a metal halide lamp can be used. The irradiation amount of ultraviolet rays is preferably an illuminance of 30 to 2,000 mW / cm 2 and, as an integrated light amount, 100 to 1000 mJ / cm 2 . The curing atmosphere may be either an air atmosphere or an inert gas (e.g., nitrogen, argon) atmosphere. When irradiating with electron beams, a commercially available electron beam irradiation device can also be used, and the irradiation amount of the electron beam is preferably 1 to 10 Mrad.

[0081] After irradiating with active energy rays for curing, if necessary, heat treatment (annealing treatment) may be performed to further promote curing. The heating temperature at that time is preferably in the range of 80 to 220°C. The heating time is preferably in the range of 10 minutes to 60 minutes.

[0082] When curing the curable composition by thermal polymerization, the heating temperature is preferably in the range of 80 to 200°C, more preferably in the range of 100 to 150°C. If the heating temperature is lower than 80°C, it is necessary to extend the heating time and there is a tendency to lack economic efficiency. If the heating temperature is higher than 200°C, not only is the energy cost high, but also the heating temperature rise time and the cooling time are long, so there is a tendency to lack economic efficiency. The polymerization conditions are not particularly limited and can be appropriately adjusted according to the type of polymerization initiator used, etc. For example, it can be carried out by reacting at a polymerization temperature of 60 to 90°C for 3 to 10 hours under an inert gas (preferably nitrogen) atmosphere.

[0083] The cured resin composition can be used for various substrates. For example, it can be used for polycarbonate, polymethyl methacrylate, polystyrene, polyester, polyolefin, polycycloolefin, polyimide, epoxy resin, melamine resin, triacetyl cellulose resin, ABS resin, AS resin, norbornene-based resin, etc.

[0084] The thickness of the cured layer to be formed can be adjusted by the coating amount as described above, and is usually less than 15 μm, preferably 10 μm or less, and more preferably 7 μm or less.

[0085] Since the obtained cured product is excellent in transparency, heat resistance, and moisture and heat resistance, it can be suitably used as a coating material for outdoor displays such as digital signage and resin substrates for automobiles.

Examples

[0086] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. Unless otherwise specified, parts and % in each example are all based on mass, and all room temperature standing conditions are 23 °C / 55% RH.

[0087] 1. Production of urethane (meth) acrylate (A) [Synthesis Example 1] In a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 169.4 g of hexamethylene diisocyanate (HDI manufactured by Tosoh Corporation, isocyanate content 50%), pentaerythritol acrylate with a hydroxyl value of 115 mgKOH / g (PEA, Aronix M-305 manufactured by Toagosei Co., Ltd., content of pentaerythritol diacrylate is 0%, content of pentaerythritol monoacrylate is 0%, content of pentaerythritol triacrylate is 60%, content of pentaerythritol tetraacrylate is 40%) 1428.7 g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-stan U-600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-1 was obtained. The obtained urethane acrylate A-1 had a solid content of 80%, a viscosity at 25 °C of about 100 mPa·S, and a hydroxyl value of 29.2 mgKOH / g in terms of solid content.

[0088] [Synthesis Example 2] In a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 249.3 g of dicyclohexylmethane 4,4-diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik), and a pentaerythritol acrylate having a hydroxyl value of 115 mgKOH / g (PEA, Aronix M-305 manufactured by Toagosei Co., Ltd., the content of pentaerythritol diacrylate is 0%, the content of pentaerythritol monoacrylate is 0%, the content of pentaerythritol triacrylate is 60%, and the content of pentaerythritol tetraacrylate is 40%) 1348.8 g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (NeoStan U-600, manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-2 was obtained. The obtained urethane acrylate A-2 had a solid content of 80%, a viscosity at 25 °C of about 80 mPa·S, and a hydroxyl value of 27.3 mgKOH / g in terms of solid content.

[0089] [Synthesis Example 3] In a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 568.9 g of dicyclohexylmethane 4,4-diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 32%), and a pentaerythritol acrylate having a hydroxyl value of 280 mgKOH / g (Aronix M-933, manufactured by Toagosei Co., Ltd., the content of pentaerythritol diacrylate is 30%, the content of pentaerythritol monoacrylate is 5%, the content of pentaerythritol triacrylate is 50%, and the content of pentaerythritol tetraacrylate is 15%) 1029.2 g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (NeoStan U-600, Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-3 was obtained. The obtained urethane acrylate A-3 had a solid content of 80%, a viscosity at 25 °C of about 350 mPa·S, and a hydroxyl value of 28.5 mgKOH / g in terms of solid content.

[0090] [Synthesis Example 4] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 217.3 g of isophorone diisocyanate (IPDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 37.7%), 1380.7 g of pentaerythritol acrylate (PEA, Aronix M-305 manufactured by Toagosei Co., Ltd., content of pentaerythritol diacrylate 0%, content of pentaerythritol monoacrylate 0%, content of pentaerythritol triacrylate 60%, content of pentaerythritol tetraacrylate 40%) with a hydroxyl value of 115 mgKOH / g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-Stan U-600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-4 was obtained. The obtained urethane acrylate A-4 had a solid content of 80%, a viscosity at 25 °C of about 110 mPa·S, and a hydroxyl value of 27.6 mgKOH / g in terms of solid content.

[0091] [Synthesis Example 5] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 511.4 g of isophorone diisocyanate (IPDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 37.7%), 1086.7 g of pentaerythritol acrylate (Aronix M-933, manufactured by Toagosei Co., Ltd., hydroxyl value 280 mgKOH / g, containing 30% of pentaerythritol diacrylate, 5% of pentaerythritol monoacrylate, 50% of pentaerythritol triacrylate, and 15% of pentaerythritol tetraacrylate), 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-stan U-600, manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-5 was obtained. The obtained urethane acrylate A-5 had a solid content of 80%, a viscosity at 25 °C of about 400 mPa·S, and a hydroxyl value of 40.8 mgKOH / g in terms of solid content.

[0092] [Synthesis Example 6] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 127.8 g of isophorone diisocyanate (IPDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 37.7%), 1470.2 g of dipentaerythritol acrylate (DPHA, Aronix M-403 manufactured by Toagosei Co., Ltd., hydroxyl value 95 mgKOH / g), 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-stan U-600, manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-6 was obtained. The obtained urethane acrylate A-6 had a solid content of 80%, a viscosity at 25 °C of about 110 mPa·S, and a hydroxyl value of 13.7 mgKOH / g in terms of solid content.

[0093] [Synthesis Example 7] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 321.2 g of dicyclohexylmethane 4,4 - diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik Industries AG, isocyanate content 32%), 1276.9 g of pentaerythritol acrylate (PEA, Aronix M - 305 manufactured by Toagosei Co., Ltd., content of pentaerythritol diacrylate 0%, content of pentaerythritol monoacrylate 0%, content of pentaerythritol triacrylate 60%, content of pentaerythritol tetraacrylate 40%) with a hydroxyl value of 115 mgKOH / g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo - Stan U - 600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70°C. The reaction was terminated when the residual isocyanate group reached 0.1% to obtain urethane acrylate A - 7. The obtained urethane acrylate A - 7 had a solid content of 80%, a viscosity at 25°C of about 140 mPa·S, and a hydroxyl value of 5.2 mgKOH / g in terms of solid content.

[0094] [Synthesis Example 8] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 615.3 g of dicyclohexylmethane 4,4 - diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 32%), 982.8 g of pentaerythritol acrylate (PEA, Aronix M - 933 manufactured by Toagosei Co., Ltd., content of pentaerythritol diacrylate 30%, content of pentaerythritol monoacrylate 5%, content of pentaerythritol triacrylate 50%, content of pentaerythritol tetraacrylate 15%) with a hydroxyl value of 280 mgKOH / g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo - Stan U - 600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70°C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A - 8 was obtained. The obtained urethane acrylate A - 8 had a solid content of 80%, a viscosity at 25°C of about 500 mPa·S, and a hydroxyl value of 6.7 mgKOH / g in terms of solid content.

[0095] [Comparative Synthesis Example 1] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 595.5 g of dicyclohexylmethane 4,4 - diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 32%), 738.7 g of polytetramethylene ether glycol (PTMEG, PTMG650 manufactured by Mitsubishi Chemical Corporation, molecular weight 650), 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo - Stan U - 600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70°C for 2 hours. Then, 263.9 g of 2 - hydroxyethyl acrylate (2HEA, manufactured by Osaka Organic Chemical Industry Co., Ltd., hydroxyl value 483 mgKOH / g) was added, and the reaction was carried out for 3 hours. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A - 9 was obtained. The obtained urethane acrylate A-9 had a solid content of 80%, a viscosity of about 2000 mPa·S at 25°C, and a hydroxyl value of 15 mgKOH / g in terms of solid content. Note that urethane acrylate A-9 is the urethane acrylate used in the example of Patent No. 4204106.

[0096] [Comparative Synthesis Example 2] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 645.6 g of a bifunctional hexamethylene diisocyanate prepolymer (HDI prepolymer, Duranate A201H manufactured by Asahi Kasei Corporation, isocyanate content 15.8%), 952.5 g of a lactone-modified acrylate (LA, Placcel FA2D manufactured by Daicel Corporation) with a hydroxyl value of 163 mgKOH / g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-Stan U-600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70°C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-10 was obtained. The obtained urethane acrylate A-10 had a solid content of 80%, a viscosity of about 1200 mPa·S at 25°C, and a hydroxyl value of 11.3 mgKOH / g in terms of solid content. Note that urethane acrylate A-10 is the urethane acrylate used in the example of Patent No. 7452588.

[0097] [Comparative Synthesis Example 3] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 210.9 g of norbornene diisocyanate (synthesized by Taisei Fine Chemical Co., Ltd., isocyanate content 47.1%), 1387.1 g of pentaerythritol acrylate (PEA, Aronix M-305 manufactured by Toagosei Co., Ltd., content of pentaerythritol diacrylate 0%, content of pentaerythritol monoacrylate 0%, content of pentaerythritol triacrylate 60%, content of pentaerythritol tetraacrylate 40%) with a hydroxyl value of 115 mgKOH / g, 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-Stan U-600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70 °C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-11 was obtained. The obtained urethane acrylate A-11 had a solid content of 80%, a viscosity at 25 °C of about 110 mPa·S, and a hydroxyl value of 15.3 mgKOH / g in terms of solid content. Note that urethane acrylate A-11 is the urethane acrylate used in Example 6481302 of the patent.

[0098] [Comparative Synthesis Example 4] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 303.6 g of 1,3-bis(isocyanatomethyl)cyclohexane (H6XDI, Takenate (registered trademark) 600 manufactured by Mitsui Chemicals, Inc., isocyanate content 43.3%), 567.3 g of pentaerythritol acrylate (PEA, Aronix M-933 manufactured by Toagosei Co., Ltd., hydroxyl value 280 mgKOH / g, content of pentaerythritol diacrylate 30%, content of pentaerythritol monoacrylate 5%, content of pentaerythritol triacrylate 50%, content of pentaerythritol tetraacrylate 15%), 727.1 g of dipentaerythritol acrylate (DPHA, Aronix M-403 manufactured by Toagosei Co., Ltd., hydroxyl value 95 mgKOH / g), 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neo-Stan U-600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out while stirring uniformly at 70°C. The reaction was terminated when the residual isocyanate group reached 0.1%, and urethane acrylate A-12 was obtained. The obtained urethane acrylate A-12 had a solid content of 80%, a viscosity at 25°C of about 400 mPa·S, and a hydroxyl value of 16.4 mgKOH / g in terms of solid content. Note that urethane acrylate A-12 is the urethane acrylate used in the example of Patent 7024558.

[0099] [Comparative Synthesis Example 5] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 535.4 g of dicyclohexylmethane 4,4 - diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 32%), 1062.7 g of pentaerythritol acrylate with a hydroxyl value of 310 mg KOH / g (Aronix M - 926 manufactured by Toagosei Co., Ltd.), 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (Neostan U - 600 manufactured by Nitto Kasei Co., Ltd.) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70°C. The reaction was terminated when the residual isocyanate groups reached 0.1%, and urethane acrylate A - 13 was obtained. The obtained urethane acrylate A - 13 had a solid content of 80%, a viscosity at 25°C of about 4800 mPa·S, and a hydroxyl value of 64.2 mg KOH / g in terms of solid content.

[0100] [Comparative Synthesis Example 6] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 127.8 g of dicyclohexylmethane 4,4 - diisocyanate (H12MDI, VESTANT (registered trademark) manufactured by Evonik, isocyanate content 32%), 1470.2 g of dipentaerythritol acrylate with a hydroxyl value of 50 mg KOH / g (DPHA, NK Ester A - 9550 manufactured by Shin - Nakamura Chemical Co., Ltd.), 399.5 g of methyl ethyl ketone as a solvent, 0.8 g of methoquinone as a polymerization inhibitor, and 1.6 g of inorganic bismuth (manufactured by Nitto Kasei Co., Ltd., Neostan U - 600) as a reaction catalyst were charged, and the reaction was carried out with uniform stirring at 70°C. The reaction was terminated when the residual isocyanate groups reached 0.1%, and urethane acrylate A - 14 was obtained. The obtained urethane acrylate A - 14 had a solid content of 80%, a viscosity at 25°C of about 110 mPa·S, and a hydroxyl value of 13.7 mg KOH / g in terms of solid content.

[0101] The following shows an overview of the synthesis conditions of each urethane acrylate and the hydroxyl value of each obtained urethane acrylate.

Table 1

Table 2

[0102] 2. Production of alkylene oxide-modified or unmodified (meth)acrylate (B) [Synthesis Example 9] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 134 g of trimethylolpropane (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight 134.2), 0.3 g of caustic potassium, and 134 g of toluene as a solvent were charged. While stirring uniformly at 140 °C, 44 g of ethylene oxide (molecular weight 44) was gradually blown into the reaction vessel and reacted. After the reaction, neutralization was carried out with acetic acid to obtain ethylene oxide-modified trimethylolpropane. 178 g of the obtained ethylene oxide-modified trimethylolpropane, 216 g of acrylic acid, 30 g of p-toluenesulfonic acid, 0.45 g of hydroquinone, and 400 g of toluene as a solvent were charged into another reaction vessel, and the mixture was heated to 110 °C while blowing air and reacted. The water generated in the dehydration reaction was removed at any time during the reaction. After the reaction, alkali washing and water washing were carried out, and toluene was recovered under reduced pressure while blowing air to obtain ethylene oxide-modified trimethylolpropane triacrylate B-1. Regarding the obtained B-1, under the following conditions 1 H-HMR 13 When analyzed by C-NMR and HPLC, the addition number of ethylene oxide was 0.9.

[0103] 1 Conditions for H-HMR analysis Apparatus: ECX-400 manufactured by JEOL Ltd. Measurement solvent: deuterated chloroform Measurement concentration: 1 wt% Measurement temperature: 50 °C Number of integrations: 16 times

[0104] 13 Conditions for C-NMR analysis Apparatus: ECX-400 manufactured by JEOL Ltd. Measurement solvent: deuterated chloroform Measurement concentration: 5 wt% Measurement temperature: room temperature Number of integrations: 4096 times

[0105] Conditions for HPLC analysis equipment Apparatus: SHIMADZU LC-10A Detector: UV 254 nm Column: GL Sciences Inertsil ODS-2 (4.6 × 150 mm) Column temperature: 40 °C Eluent: acetonitrile / 0.1% phosphoric acid = 60 / 40 Flow rate: 0.6 ml / min Sample injection volume: 2 μl Sample concentration: 1 wt%

[0106] [Synthesis Example 10] Into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc., 134 g of trimethylolpropane (molecular weight 134.2, manufactured by Tokyo Chemical Industry Co., Ltd.), 0.3 g of potassium hydroxide, and 134 g of toluene as a solvent were charged. While stirring uniformly at 140 °C, 176 g of ethylene oxide (molecular weight 44) was gradually blown into the reaction vessel and reacted. After the reaction, neutralization was carried out with acetic acid to obtain ethylene oxide-modified trimethylolpropane. 310 g of the obtained ethylene oxide-modified trimethylolpropane, 216 g of acrylic acid, 30 g of p-toluenesulfonic acid, 0.45 g of hydroquinone, and 600 g of toluene as a solvent were charged into another reaction vessel, and the mixture was heated to 110 °C while blowing air and the reaction was carried out. The water generated by the dehydration reaction was removed at any time during the reaction. After the reaction, alkali washing and water washing were carried out, and toluene was recovered under reduced pressure while blowing air to obtain ethylene oxide-modified trimethylolpropane triacrylate B-2. Regarding the obtained B-2, under the conditions described above 1 H-HMR, 13 C-NMR, and HPLC analysis showed that the added number of ethylene oxide was 3.7.

[0107] [Synthesis Example 11] 134 g of trimethylolpropane (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight 134.2), 0.3 g of caustic potassium, and 134 g of toluene as a solvent were charged into a reaction vessel equipped with a thermometer, a reflux condenser, a stirrer, a dropping funnel, etc. While stirring uniformly at 140 °C, 308 g of ethylene oxide (molecular weight 44) was gradually blown into the reaction vessel and reacted. After the reaction, neutralization was carried out with acetic acid to obtain ethylene oxide-modified trimethylolpropane. 442 g of the obtained ethylene oxide-modified trimethylolpropane, 216 g of acrylic acid, 30 g of p-toluenesulfonic acid, 0.45 g of hydroquinone, and 800 g of toluene as a solvent were charged into another reaction vessel, and the mixture was heated to 110 °C while blowing air and the reaction was carried out. The water generated by the dehydration reaction was removed at any time during the reaction. After the reaction, alkali washing and water washing were carried out, and toluene was recovered under reduced pressure while blowing air to obtain ethylene oxide-modified trimethylolpropane triacrylate B-3. Regarding the obtained B-3, 1 H-HMR, 13 C-NMR, HPLC analysis showed that the added number of ethylene oxide was 6.4.

[0108] [Synthesis Example 12] Into a reaction vessel equipped with a thermometer, reflux condenser, stirrer, dropping funnel, etc., 178 g of trimethylolpropane (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight 134.2), 216 g of acrylic acid, 30 g of p-toluenesulfonic acid, 0.45 g of hydroquinone, and 400 g of toluene as a solvent were charged, and the mixture was heated to 110 °C while blowing air to carry out the reaction. The water generated by the dehydration reaction was removed at any time during the reaction. After the reaction, alkali washing and water washing were carried out, and toluene was recovered under reduced pressure while blowing air to obtain ethylene oxide non-modified trimethylolpropane triacrylate B-4. The added number of moles of ethylene oxide in the obtained B-4 is 0.

[0109] The added numbers of moles (mol) of ethylene oxide in the obtained ethylene oxide-modified trimethylolpropane triacrylates B-1 to B-3 are summarized as follows.

Table 3

[0110] 3. Preparation of curable resin composition [Example 1] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9) 10 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide 3.7) 25 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added amount of ethylene oxide 6.4) 5 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added as a diluent to prepare a curable composition with a solid content of 50.0%.

[0111] [Example 2] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 80 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added number of ethylene oxide is 0.9) 5 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added number of ethylene oxide is 3.7) 12.5 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added number of ethylene oxide is 6.4) 2.5 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0112] [Example 3] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 20 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9) 20 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide 3.7) 50 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added amount of ethylene oxide 6.4) 10 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%. 。

[0113] [Example 4] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9) 18 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide 3.7) 12 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added amount of ethylene oxide 6.4) 10 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0114] [Example 5] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mgKOH / g. The hydroxyl value is 29.2 mgKOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added number of ethylene oxide is 0.9) 4 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added number of ethylene oxide 3.7) 32 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added number of ethylene oxide 6.4) 4 g, benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) 8 g as an ultraviolet absorber, hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) 1 g as a light stabilizer, and monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) 5 g as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0115] [Example 6] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mgKOH / g. The hydroxyl value is 29.2 mgKOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9) 4 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide 3.7) 26 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added amount of ethylene oxide 6.4) 10 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0116] [Example 7] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9) 18 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide 3.7) 18 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added amount of ethylene oxide 6.4) 4 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0117] [Comparative Example 1] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 100 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0118] [Comparative Example 2] 30 g of ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9), 60 g of ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide is 3.7), 10 g of ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added amount of ethylene oxide is 6.4), 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0119] [Comparative Example 3] 60 g of urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g), 10 g of ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added amount of ethylene oxide is 0.9), 30 g of ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added amount of ethylene oxide is 3.7), 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0120] [Comparative Example 4] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added number of ethylene oxide is 3.7) 30 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added number of ethylene oxide is 6.4) 10 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0121] [Comparative Example 5] Urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 29.2 mg KOH / g) 60 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added number of ethylene oxide is 0.9) 24 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added number of ethylene oxide is 6.4) 16 g, 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photopolymerization initiator (Omnirad TPO manufactured by IGM RESINS) as a photopolymerization initiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0122] The outlines of the compositions of the curable compositions of Examples 1 to 7 and Comparative Examples 1 to 5 are summarized below.

Table 4

[0123] [Example 8] A curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-2 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mgKOH / g; hydroxyl value: 27.3 mgKOH / g) was used instead of urethane acrylate A-1.

[0124] [Example 9] A curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mgKOH / g; hydroxyl value: 28.5 mgKOH / g) was used instead of urethane acrylate A-1.

[0125] [Example 10] A curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mgKOH / g; hydroxyl value: 27.6 mgKOH / g) was used instead of urethane acrylate A-1.

[0126] [Example 11] A curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mgKOH / g; hydroxyl value: 40.8 mgKOH / g) was used instead of urethane acrylate A-1.

[0127] [Example 12] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 60 g of urethane acrylate A-6 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 95 mg KOH / g; hydroxyl value is 13.7 mg KOH / g) was mixed.

[0128] [Example 13] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 60 g of urethane acrylate A-7 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value is 5.2 mg KOH / g) was mixed.

[0129] [Example 14] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 60 g of urethane acrylate A-8 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value is 6.7 mg KOH / g) was mixed.

[0130] [Example 15] Instead of mixing 10 g of ethylene oxide-modified trimethylolpropane triacrylate B-1 (the addition number of ethylene oxide is 0.9), a curable composition was prepared in the same manner as in Example 1, except that 10 g of alkylene oxide-unmodified (meth)acrylate B-4 was mixed.

[0131] [Comparative Example 6] Instead of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-9 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI), polytetramethylene ether glycol (PTMEG), and 2-hydroxyethyl acrylate (2HEA); hydroxyl value: 483 mgKOH / g) was used.

[0132] [Comparative Example 7] Instead of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-10 (synthesized from a hexamethylene diisocyanate (HDI)-based prepolymer and a lactone-modified acrylate; hydroxyl value: 11.3 mgKOH / g) was used.

[0133] [Comparative Example 8] Instead of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that urethane acrylate A-11 (synthesized from norbornene diisocyanate and pentaerythritol acrylate with a hydroxyl value of 115 mgKOH / g; hydroxyl value: 15.3 mgKOH / g) was used.

[0134] [Comparative Example 9] 100 g of urethane acrylate A-12 (synthesized from 1,3-bis(isocyanatomethyl)cyclohexane (H6XDI), pentaerythritol acrylate with a hydroxyl value of 280 mgKOH / g, and dipentaerythritol acrylate with a hydroxyl value of 95 mgKOH / g; hydroxyl value: 16.4 mgKOH / g), 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (ADEKA STAB LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0135] The outlines of the compositions of the curable compositions of Example 1, Examples 8 to 15, and Comparative Examples 6 to 9 are summarized below. [Table 5] The units of the numerical values in the table are g unless otherwise specified.

[0136] [Example 16] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 29.2 mg KOH / g) and 30 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) were mixed.

[0137] [Example 17] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 54 g of urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 29.2 mg KOH / g) and 6 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) were mixed.

[0138] [Example 18] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 6 g of urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 115 mg KOH / g; hydroxyl value: 29.2 mg KOH / g) and 54 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) were mixed.

[0139] [Example 19] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 40 g of urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 115 mg KOH / g; hydroxyl value: 29.2 mg KOH / g) and 40 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) were mixed.

[0140] [Example 20] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 10 g of urethane acrylate A-1 (synthesized from hexamethylene diisocyanate (HDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 115 mg KOH / g; hydroxyl value: 29.2 mg KOH / g) and 10 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) were mixed.

[0141] [Example 21] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-2 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 27.3 mg KOH / g) and 30 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) were mixed.

[0142] [Example 22] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 28.5 mg KOH / g) and 30 g of urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 27.6 mg KOH / g) were mixed.

[0143] [Example 23] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-2 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 27.3 mg KOH / g) and 30 g of urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 40.8 mg KOH / g) were mixed.

[0144] [Example 24] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 27.6 mg KOH / g) and 30 g of urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 40.8 mg KOH / g) were mixed.

[0145] [Example 25] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 40.8 mg KOH / g) and 30 g of urethane acrylate A-6 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 95 mg KOH / g; hydroxyl value: 13.7 mg KOH / g) were mixed.

[0146] [Example 26] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 50 g of urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 40.8 mg KOH / g) and 10 g of urethane acrylate A-6 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 95 mg KOH / g; hydroxyl value: 13.7 mg KOH / g) were mixed.

[0147] [Example 27] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 10 g of urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 280 mg KOH / g; hydroxyl value: 40.8 mg KOH / g) and 50 g of urethane acrylate A-6 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 95 mg KOH / g; hydroxyl value: 13.7 mg KOH / g) were mixed.

[0148] [Example 28] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-7 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 115 mg KOH / g; hydroxyl value: 5.2 mg KOH / g) and 30 g of urethane acrylate A-8 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 280 mg KOH / g; hydroxyl value: 6.7 mg KOH / g) were mixed.

[0149] [Example 29] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 10 g of urethane acrylate A-7 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 115 mg KOH / g; hydroxyl value: 5.2 mg KOH / g) and 50 g of urethane acrylate A-8 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) having a hydroxyl value of 280 mg KOH / g; hydroxyl value: 6.7 mg KOH / g) were mixed.

[0150] [Example 30] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 50 g of urethane acrylate A-7 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 5.2 mg KOH / g) and 10 g of urethane acrylate A-8 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 6.7 mg KOH / g) were mixed.

[0151] [Example 31] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-7 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g; hydroxyl value: 5.2 mg KOH / g) and 30 g of urethane acrylate A-8 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g; hydroxyl value: 6.7 mg KOH / g) were mixed, and alkylene oxide non-modified (meth)acrylate B-4 was mixed instead of ethylene oxide modified trimethylolpropane triacrylate B-1 (the added number of ethylene oxide: 0.9).

[0152] The outlines of the compositions of the curable compositions of Examples 16 to 31 are summarized below.

Table 6

[0153] [Comparative Example 10] Urethane acrylate A-2 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 27.3 mg KOH / g) 50 g, urethane acrylate A-3 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g. The hydroxyl value is 28.5 mg KOH / g) 50 g, 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0154] [Comparative Example 11] Urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 27.6 mg KOH / g) 40 g, urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g. The hydroxyl value is 40.8 mg KOH / g) 20 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the addition number of ethylene oxide is 0.9) 28 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the addition number of ethylene oxide 3.7) 8 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the addition number of ethylene oxide 6.4) 4 g, 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0155] [Comparative Example 12] Urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 27.6 mg KOH / g) 40 g, urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g. The hydroxyl value is 40.8 mg KOH / g) 20 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the added number of ethylene oxide is 0.9) 22 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the added number of ethylene oxide 3.7) 4 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the added number of ethylene oxide 6.4) 14 g, benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) 8 g as an ultraviolet absorber, hindered amine-based light stabilizer (ADEKA STAB LA-87 manufactured by ADEKA Corporation) 1 g as a light stabilizer, and monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) 5 g as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0156] [Comparative Example 13] Urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 27.6 mg KOH / g) 40 g, urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g. The hydroxyl value is 40.8 mg KOH / g) 20 g, ethylene oxide-modified trimethylolpropane triacrylate B-1 (the addition number of ethylene oxide is 0.9) 4 g, ethylene oxide-modified trimethylolpropane triacrylate B-2 (the addition number of ethylene oxide 3.7) 12 g, ethylene oxide-modified trimethylolpropane triacrylate B-3 (the addition number of ethylene oxide 6.4) 24 g, 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (ADEKA STAB LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0157] [Comparative Example 14] Instead of mixing 60 g of urethane acrylate A-1, a curable composition was prepared in the same manner as in Example 1, except that 30 g of urethane acrylate A-13 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and sorbitol EO-modified acrylate with a hydroxyl value of 310 mg KOH / g. The hydroxyl value is 64.2 mg KOH / g) and 30 g of urethane acrylate A-4 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 27.6 mg KOH / g) were mixed.

[0158] [Comparative Example 15] Instead of mixing 60 g of urethane acrylate A-1, urethane acrylate A-14 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and dipentaerythritol acrylate (PEA) with a hydroxyl value of 50 mg KOH / g. The hydroxyl value is mg KOH / g) was mixed with 30 g of urethane acrylate A-5 (synthesized from isophorone diisocyanate (IPDI) and pentaerythritol acrylate (PEA) with a hydroxyl value of 280 mg KOH / g. The hydroxyl value is 13.7 mg KOH / g) in an amount of 30 g. A curable composition was prepared in the same manner as in Example 1 except for this.

[0159] [Comparative Example 16] Instead of mixing 60 g of urethane acrylate A-1, urethane acrylate A-13 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H 12 MDI) and sorbitol EO-modified acrylate with a hydroxyl value of 310 mg KOH / g. The hydroxyl value is 64.2 mg KOH / g) was mixed with 30 g of urethane acrylate A-14 (synthesized from dicyclohexylmethane 4,4-diisocyanate (H12MDI) and dipentaerythritol acrylate (PEA) with a hydroxyl value of 50 mg KOH / g. The hydroxyl value is 11.8 mg KOH / g) in an amount of 30 g. A curable composition was prepared in the same manner as in Example 1 except for this.

[0160] [Comparative Example 17] Preparation Example of Patent 4204106 Urethane acrylate A-9 (dicyclohexylmethane 4,4-diisocyanate (H 12It is synthesized from diphenylmethane diisocyanate (MDI), polytetramethylene ether glycol (PTMEG), and 2-hydroxyethyl acrylate (2HEA). 24 g of a hydroxyl value of 483 mg KOH / g, 25 g of dipentaerythritol hexaacrylate (DPHA) B-5, 62 g of tris(2-acryloyloxyethyl) isocyanurate (TAIC) B-6, 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0161] [Comparative Example 18] Preparation Example of Patent 6481302 Urethane acrylate A-11 (synthesized from norbornene diisocyanate and pentaerythritol acrylate with a hydroxyl value of 115 mg KOH / g. The hydroxyl value is 15.3 mg KOH / g) was mixed with 91 g, 9 g of ethylene oxide (10 mol) -added bisphenol A diacrylate B-10, 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator, and stirred. Then 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0162] [Comparative Example 19] Preparation Example of Patent 7024558 Urethane acrylate A-12 (synthesized from 1,3-bis(isocyanatomethyl)cyclohexane (H6XDI), pentaerythritol acrylate with a hydroxyl value of 280 mg KOH / g, and dipentaerythritol acrylate with a hydroxyl value of 95 mg KOH / g; hydroxyl value is 16.4 mg KOH / g) (100 g), 8 g of a benzotriazole-based light stabilizer (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber, 1 g of a hindered amine-based light stabilizer (ADEKA STAB LA-87 manufactured by ADEKA Corporation) as a light stabilizer, and 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator were mixed and stirred, and 114 g of 1-methoxy-2-propanol (PGM) was added to prepare a curable composition with a solid content of 50.0%.

[0163] The outlines of the compositions of the curable compositions of Comparative Examples 10 to 19 are summarized below.

Table 7

[0164] [Example 32] A curable composition was prepared in the same manner as in Example 1, except that 5 g of 2,2'-azobis(isobutyronitrile) (manufactured by Fujifilm Wako Pure Chemical Corporation) was mixed instead of 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator.

[0165] [Example 33] A curable composition was prepared in the same manner as in Example 1, except that 5 g of benzoyl peroxide (Niper BO manufactured by NOF Corporation) was mixed instead of 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as a photoinitiator.

[0166] [Example 34] Instead of mixing 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as the photoinitiator, a curable composition was prepared in the same manner as in Example 1, except that 5 g of α-hydroxyalkylphenone (Omnirad 184 manufactured by IGM RESINS) was mixed.

[0167] [Example 35] Instead of mixing 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as the photoinitiator, a curable composition was prepared in the same manner as in Example 1, except that 4 g of α-hydroxyalkylphenone (Omnirad 184 manufactured by IGM RESINS) and 2 g of benzophenone (manufactured by Matsugaki Pharmaceutical Co., Ltd.) were mixed.

[0168] [Example 36] Instead of mixing 5 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) as the photoinitiator, a curable composition was prepared in the same manner as in Example 1, except that 4 g of α-hydroxyalkylphenone (Omnirad 184 manufactured by IGM RESINS) and 2 g of thioxanthone (Omnirad DETX manufactured by IGM RESINS) were mixed.

[0169] [Example 37] A curable composition was prepared in the same manner as in Example 1, except that 8 g of a monoacylphosphine oxide-based photoinitiator (Omnirad TPO manufactured by IGM RESINS) was mixed as the photoinitiator.

[0170] [Example 38] Instead of mixing 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, 6 g of a triazine-based ultraviolet absorber (Tinuvin 400 manufactured by BASF) and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) were mixed, and a curable composition was prepared in the same manner as in Example 1.

[0171] [Example 39] Instead of mixing 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, 6 g of a cyanoacrylate-based light stabilizer (Uvinul 3035 manufactured by BASF) and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) were mixed, and a curable composition was prepared in the same manner as in Example 1.

[0172] [Example 40] Instead of mixing 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, 1 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) were mixed, and a curable composition was prepared in the same manner as in Example 1.

[0173] [Example 41] Instead of mixing 8 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) as an ultraviolet absorber and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) as a light stabilizer, a curable composition was prepared in the same manner as in Example 1, except that 14 g of a benzotriazole-based ultraviolet absorber (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) and 1 g of a hindered amine-based light stabilizer (Adekastab LA-87 manufactured by ADEKA Corporation) were mixed.

[0174] The outlines of the compositions of the curable compositions of Examples 32 to 41 are summarized below.

Table 8

[0175] 4. Performance Evaluation of Curable Resin Composition [Sample Preparation Method] The resin compositions prepared in the examples and comparative examples were coated on a PET film (Cosmoshine A4360 manufactured by Toyobo Co., Ltd.: thickness 100 μm) with a bar coater and pre-dried at 80°C for 1 minute. Next, ultraviolet irradiation was performed using an ultraviolet irradiation device (Light Hammer 10 manufactured by Heraeus Co., Ltd.) under air so that the irradiation dose was 500 mJ / cm2 (irradiance 1,500 mW / cm2) to produce a coating layer with a film thickness of 5 μm.

[0176] [Heat Resistance Test: Adhesion] For the coating layer manufactured above, a test piece of 100 mm × 150 mm was prepared. Subsequently, the test piece was left in a thermo-hygrostat set at a temperature of 120°C for 500 hours and then taken out. For the test piece after the test, a 100-square grid of 1 mm × 1 mm in size was made on the surface of the cured film using a cutter knife, and after sticking cellophane tape on the grid and peeling it off, the number of grids where the cured film remained without peeling was used to evaluate according to the following evaluation criteria. A: No peeling of the cured film B: Number of grids that did not peel "70 - 99 / 100" C: Number of grids that did not peel "30 - 69 / 100" D: Number of unpeeled squares less than 30

[0177] [Humid heat test: Transparency] For the coating layer manufactured above, a test piece of 100 mm × 150 mm was prepared. Subsequently, the test piece was placed in a thermo-hygrostat (manufactured by Isuzu Manufacturing Co., Ltd., HPCF-288-40) set at a temperature of 85°C and a humidity of 85% RH for 1000 hours, and then the test piece was taken out. For the test piece after the humid heat resistance test, haze measurement was performed using a haze meter (NDH-5000, manufactured by Nippon Denshoku Industries Co., Ltd.), and the haze before and after the test was evaluated according to the following criteria. A: ΔHAZE = 2 or less B: ΔHAZE = 2 - 4 C: ΔHAZE = 4 - 6 D: ΔHAZE = 6 or more

[0178] [Humid heat test: Adhesion] For the test piece that underwent the humid heat resistance test under the same test conditions as during the transparency test, 100 squares with a size of 1 mm × 1 mm were made on the surface of the cured film using a cutter knife. After attaching and then peeling off cellophane tape on the squares, the evaluation was performed according to the following evaluation criteria based on the number of squares where the cured film remained without peeling. A: No peeling of the cured film B: Number of unpeeled squares "70 - 99 / 100" C: Number of unpeeled squares "30 - 69 / 100" D: Number of unpeeled squares less than 30

[0179] The test results are summarized and shown below.

Table 9

Table 10

Table 11

Table 12

Table 13

Industrial Applicability

[0180] According to the present invention, there is provided a curable composition capable of forming a hard coat layer excellent in heat resistance and heat and moisture resistance. The curable composition according to the present invention can be used to form a hard coat layer for many resin films and molded articles such as polyethylene terephthalate (PET) resin, polycarbonate (PC) resin, poly(meth)acrylate (PMA or PMMA) resin, etc. In particular, since it is used outdoors such as equipment mounted on automobiles and portable devices, it is useful for forming a hard coat layer for equipment that requires higher heat resistance and heat and moisture resistance.

Claims

1. (1) A urethane (meth)acrylate (A1) obtained by reacting a (meth)acrylate (a1-1) having a hydroxyl value of 90 to 180 mg KOH / g and having a structure derived from a polyhydric alcohol, an aliphatic isocyanate, an alicyclic isocyanate having no bridging structure, an aromatic isocyanate, and a polyvalent isocyanate (a2) selected from hydrogenated products thereof, and optionally a polyol (a3), and a urethane (meth)acrylate (A2) obtained by reacting a (meth)acrylate (a1-2) having a hydroxyl value of 200 to 300 mg KOH / g and having a structure derived from a polyhydric alcohol, an aliphatic isocyanate, an alicyclic isocyanate having no bridging structure, an aromatic isocyanate, and a polyvalent isocyanate (a2) selected from hydrogenated products thereof, and optionally a polyol (a3), and (2) an alkylene oxide-modified tri(meth)acrylate (B), wherein the alkylene oxide-modified tri(meth)acrylate (B) is a (meth)acrylate (B1) having an average number of repeating units of alkylene oxide of 0 to 2.0, a (meth)acrylate (B2) having an average number of repeating units of alkylene oxide of 3.0 to 5.0, and a (meth)acrylate (B3) having an average number of repeating units of alkylene oxide of 6.0 to 8.0, a curable resin composition.

2. The curable resin composition according to claim 1, comprising 5 to 50% by mass of the (meth)acrylate (B1), 20 to 90% by mass of the (meth)acrylate (B2), and 5 to 30% by mass of the (meth)acrylate (B3).

3. The curable resin composition according to claim 1, wherein the urethane (meth)acrylate (A) comprises a urethane (meth)acrylate (A1) obtained by reacting a (meth)acrylate (a1-1) having a hydroxyl value of 110 to 180 mg KOH / g and having a structure derived from a polyhydric alcohol, an aliphatic isocyanate, an alicyclic isocyanate having no bridging structure, an aromatic isocyanate, and a polyvalent isocyanate (a2) selected from hydrogenated products thereof, and optionally a polyol (a3).

4. The curable resin composition according to claim 1, wherein the mass ratio of the urethane (meth) acrylate (A1) to the urethane (meth) acrylate (A2) is 10:1 to 1:

2.

5. The curable resin composition according to claim 1, wherein the urethane (meth) acrylate (A) has a structure derived from at least one polyhydric alcohol selected from the group consisting of glycerin, pentaerythritol, dipentaerythritol, and tripentaerythritol.

6. The curable resin composition according to claim 5, wherein the urethane (meth) acrylate (A) has a structure derived from either or both of dipentaerythritol and tripentaerythritol.

7. The curable resin composition according to claim 1, wherein the polyvalent isocyanate (a2) is an alicyclic isocyanate having no bridging structure.

8. The curable resin composition according to claim 7, wherein the alicyclic isocyanate is isophorone diisocyanate or dicyclohexylmethane diisocyanate.

9. The curable resin composition according to claim 1, wherein the hydroxyl value of the urethane (meth) acrylate (A) is 0.1 to 10 mgKOH / g.

10. The curable resin composition according to claim 1, wherein the alkylene oxide-modified tri(meth)acrylate (B) is selected from ethylene oxide-modified trimethylolpropane triacrylate and propylene oxide-modified trimethylolpropane triacrylate.

11. A cured layer obtained by curing the curable resin composition according to any one of claims 1 to 10.

12. An article having the cured layer according to claim 11 on the entire surface, one surface, or a part of a substrate.

13. A method for forming a coating layer, comprising applying the curable resin composition according to any one of claims 1 to 10 onto a substrate, irradiating the curable resin composition with active energy rays, or heating the curable resin composition to cure the curable resin composition.

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