JP2017218490A - Coating agent, resin cured film, and laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating agent which can have a sufficiently low viscosity even when the concentration of a curable resin is sufficiently increased and can form a resin cured film excellent in self-repair properties and heat resistance, a resin cured film formed of the coating agent, and a laminate including the same.SOLUTION: The coating agent contains a curable resin obtained by reacting: an isocyanate group-terminated prepolymer obtained by reacting (A) a polyisocyanate, (B) a specific divinyl compound, and (C) a polysiloxane having at least two hydroxy groups; and at least one compound selected from the group consisting of (D1) a C2-C13 diol compound, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) a specific hydroxyalkyl (meth)acrylate.SELECTED DRAWING: None

Description

  The present invention relates to a coating agent containing a curable resin, a cured resin film, and a laminate including the same.

  Conventionally, a coating agent containing a resin component on the surface of a substrate such as plastic, paper, metal, fiber, glass, or wood to protect it from abrasion due to friction, alteration due to heat, contamination due to adhesion of dust or water, etc. The coating process is done. In particular, a coating agent containing a curable resin that is cured by polymerization or crosslinking is frequently used because the formed resin cured film is excellent in scratch resistance.

  By the way, characteristics required for the above-mentioned resin cured film include, for example, heat resistance that does not denature even during thermoforming of coated plastic and the like, and self-repairing ability that can repair a scratch even if it is scratched. Moreover, when a base material is an article weak to heat, it is calculated | required that a resin cured film is formed by the method which does not require high temperature.

  So far, active energy ray-curable coating agents have been proposed, and self-healing properties of cured resin films have been studied. For example, Patent Document 1 below discloses an active energy ray-curable composition containing urethane (meth) acrylate obtained by reacting organic isocyanate with polycarbonate diol and hydroxy-modified (meth) acrylate.

JP 2004-35600 A

  The urethane (meth) acrylate described in Patent Document 1 has a tendency that the viscosity of the coating agent tends to be too high, and it becomes difficult to handle and uneven coating tends to occur. was there. In the method of reducing the viscosity of the coating agent with a solvent, etc., a large amount of solvent must be used, and the process of distilling off later becomes complicated, or the working environment deteriorates because the amount of volatilization of the solvent increases. Undesirable in terms.

  The present invention has been made in view of the above-mentioned conventional problems, and can have a sufficiently low viscosity even when the content concentration of the curable resin is sufficiently increased, and is a cured resin film excellent in self-repairability and heat resistance. It is an object of the present invention to provide a coating agent capable of forming a film, a cured resin film formed by the coating agent, and a laminate including the same.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by using a curable resin having a specific structure, and have completed the present invention.

  The coating agent of the present invention is obtained by reacting (A) polyisocyanate, (B) a compound represented by the following general formula (1-1), and (C) polysiloxane having at least two hydroxy groups. An isocyanate group-terminated prepolymer, (D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) in the following general formula (2) It contains a curable resin obtained by reacting at least one compound selected from the group consisting of the hydroxyalkyl (meth) acrylates represented.

［式（１−１）中、Ｒ^１１及びＲ^１２はそれぞれ独立に水素原子又はメチル基を表し、Ｒ^２１及びＲ^２２はそれぞれ独立に単結合又はエーテル結合を含んでいてもよい炭素数１〜１２のアルキレン基を表し、Ｘは下記一般式（１−２）で表される２価の基を表し、

｛式（１−２）中、Ａ^１１及びＡ^１２はそれぞれ独立に炭素数２〜４のアルキレン基を表し、Ｒ^３１及びＲ^３２はそれぞれ独立に炭素数１〜３のアルキル基、フェニル基又はハロゲノ基を表し、Ｒ^４は単結合、−ＣＲ^５ _２−（ただし、Ｒ^５は水素原子、炭素数１〜３のアルキル基又はフェニル基を表す）で表される基又は−ＳＯ_２−を表し、ｂ１及びｂ２はそれぞれ独立に０〜２の整数を表し、ｃ１及びｃ２はそれぞれ独立に０〜１０の整数を表す。｝
ａは１〜１０の整数を表す。］

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

［式（２）中、Ｒ^５は水素原子又はメチル基を表し、Ｒ^６は炭素数２〜１０のアルキレン基を表す。］

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ]

  By containing the specific curable resin, the coating agent of the present invention can have a sufficiently low viscosity even when the content concentration is sufficiently increased, and is excellent in coating processability. Moreover, the coating agent of this invention can form the resin cured film excellent in self-repairing property and heat resistance, while having such a low viscosity.

  In addition, the coating agent of the present invention can sufficiently cure the specific curable resin by a radical polymerization reaction with actinic rays, and therefore has a longer curing time due to a post-curing reaction than a cationic curing coating agent. There is also an advantage that problems such as conversion are less likely to occur.

  The present invention also provides a cured resin film obtained by curing the coating agent according to the present invention.

  The cured resin film of the present invention is a cured product of the coating agent according to the present invention, so that it can have excellent self-repairability and heat resistance. Moreover, since the coating agent which concerns on the said this invention is excellent in coating processability, the coating nonuniformity is suppressed and the resin cured film of this invention can have a favorable external appearance.

  The present invention also provides a laminate comprising a substrate and the cured resin film according to the present invention provided on the substrate.

  Even if the content of the curable resin is sufficiently increased, the coating agent can have a sufficiently low viscosity, and can form a cured resin film excellent in self-repairability and heat resistance, and is formed by the coating agent. A cured resin film and a laminate including the resin cured film can be provided.

  The coating agent of this embodiment includes (A) polyisocyanate (hereinafter sometimes referred to as (A) component), (B) a compound represented by the following general formula (1-1) (hereinafter referred to as (B) component) In some cases), and (C) an isocyanate group-terminated prepolymer obtained by reacting (C) a polysiloxane having at least two hydroxy groups (hereinafter also referred to as component (C)), and (D1) carbon number 2 to 13 diol compounds (hereinafter also referred to as (D1) component), (D2) a compound having an anionic hydrophilic group and at least two active hydrogens (hereinafter also referred to as (D2) component), And (D3) at least one compound selected from the group consisting of hydroxyalkyl (meth) acrylates represented by the following general formula (2) (hereinafter sometimes referred to as (D3) component) (Hereinafter, (sometimes referred to D) component) containing a curable resin obtained by reacting, with.

［式（１−１）中、Ｒ^１１及びＲ^１２はそれぞれ独立に水素原子又はメチル基を表し、Ｒ^２１及びＲ^２２はそれぞれ独立に単結合又はエーテル結合を含んでいてもよい炭素数１〜１２のアルキレン基を表し、Ｘは下記一般式（１−２）で表される２価の基を表し、

｛式（１−２）中、Ａ^１１及びＡ^１２はそれぞれ独立に炭素数２〜４のアルキレン基を表し、Ｒ^３１及びＲ^３２はそれぞれ独立に炭素数１〜３のアルキル基、フェニル基又はハロゲノ基を表し、Ｒ^４は単結合、−ＣＲ^５ _２−（ただし、Ｒ^５は水素原子、炭素数１〜３のアルキル基又はフェニル基を表す）で表される基又は−ＳＯ_２−を表し、ｂ１及びｂ２はそれぞれ独立に０〜２の整数を表し、ｃ１及びｃ２はそれぞれ独立に０〜１０の整数を表す。｝
ａは１〜１０の整数を表す。］

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

In the present specification, in the formulas (1-1) and (1-2), when a is 2 or more, a plurality of A ¹¹ , A ¹² , R ³¹ , R ³² and R ⁴ are the same. When b1 is 2, a plurality of R ³¹ may be the same or different, and when b2 is 2, a plurality of R ³² may be the same. May be different.

［式（２）中、Ｒ^５は水素原子又はメチル基を表し、Ｒ^６は炭素数２〜１０のアルキレン基を表す。］

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ]

  As the component (A), a compound having two or more isocyanate groups can be used, and examples thereof include modified polyisocyanates such as diisocyanate, triisocyanate, tetraisocyanate, diisocyanate dimer or trimer.

  Examples of the diisocyanate include aliphatic diisocyanate, alicyclic diisocyanate, and aromatic diisocyanate. Examples of these diisocyanates include aliphatic diisocyanate compounds such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; isophorone diisocyanate, hydrogenated xylylene diisocyanate, dicyclohexylmethane diisocyanate, norbornane diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane. And alicyclic diisocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate (MDI), naphthalene diisocyanate, tolidine diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, and the like.

  Examples of the triisocyanate and tetraisocyanate include triphenylmethane triisocyanate, dimethyltriphenylmethane tetraisocyanate, and tris (isocyanatophenyl) -thiophosphate.

  The modified polyisocyanate derived from diisocyanate is not particularly limited as long as it has two or more isocyanate groups. For example, biuret structure, isocyanurate structure, urethane structure, uretdione structure, allophanate structure, trimer structure And the like, adducts of aliphatic isocyanates of trimethylolpropane, polymeric MDI, and the like.

  The component (A) is preferably a diisocyanate, more preferably an aliphatic diisocyanate and an alicyclic diisocyanate, more preferably hexamethylene diisocyanate, isophorone, from the viewpoint that coloring of the formed resin cured film is further suppressed and self-healing properties are more excellent. More preferred are diisocyanate, dicyclohexylmethane diisocyanate, norbornane diisocyanate and 1,3-bis (isocyanatomethyl) cyclohexane.

  Polyisocyanate may be used individually by 1 type, or may be used in combination of 2 or more type.

The component (B) is a compound represented by the above general formula (1-1), but R ¹¹ and R ¹² in the general formula (1-1) are improved in workability by reducing the viscosity of the coating agent ( In particular, a hydrogen atom is preferable from the viewpoint of improvement in operability in application to a substrate or the like.

R ²¹ and R ²² in the general formula (1-1) are preferably single bonds from the viewpoint that the cured resin film to be formed is more excellent in self-repairability and heat resistance.

When R ²¹ or R ²² is an alkylene group having 1 to 12 carbon atoms that may contain an ether bond, for example, a methylene group, an ethylene group, a trimethylene group, a propylene group, an n-butylene group, an n-pentylene group, n- hexylene group, n- heptylene group, n- octylene _{group, - (CH 2) 2 -O} -CH 2 - , and the like.

A ¹¹ and A ¹² in the general formula (1-2) are preferably an ethylene group and a propylene group, and more preferably an ethylene group, from the viewpoint that the cured resin film formed is more excellent in self-repairability and heat resistance.

  C1 and c2 in the general formula (1-2) are preferably 0 to 4 and more preferably 0 to 2 from the viewpoint that the cured resin film formed is more excellent in self-repairability and heat resistance.

R ³¹ and R ³² in the general formula (1-2) are preferably an alkyl group having 1 to 3 carbon atoms from the viewpoint that the cured resin film to be formed is more excellent in self-repairability and heat resistance.

  B1 and b2 in the general formula (1-2) are preferably 0 from the viewpoint that the cured resin film to be formed is more excellent in self-repairability and heat resistance.

R ⁴ in the general formula (1-2), from the viewpoint of self-healing property and heat resistance of the resin cured film to be formed more excellent, -CR 5 ² _- preferably a group represented by, as R ⁵ is A hydrogen atom or a methyl group is preferable, and a methyl group is more preferable.

  In the general formula (1-1), 1 to 6 is preferable and 1 to 3 is more preferable from the viewpoint that the cured resin film to be formed has better self-repairability and heat resistance.

［式（３）中、Ｘ及びａは、上記一般式（１−１）におけるＸ及びａと同義である。］ The compound represented by the general formula (1) can be obtained, for example, by reacting a compound represented by the following general formula (3) with a terminal unsaturated carboxylic acid.

[In Formula (3), X and a are synonymous with X and a in the said General formula (1-1). ]

  The compound represented by the general formula (3) can be obtained, for example, by a reaction between a bisphenol compound or a biphenyl compound and epichlorohydrin. Examples of the bisphenol compound include bisphenol A, bisphenol F, bisphenol AD, bisphenol S, those having a halogeno group substituted on their benzene rings, and their alkylene oxide adducts. Examples of the biphenyl compound include 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl and the like.

［式（４）中、Ｒ^７は上記一般式（１−１）におけるＲ^１１及びＲ^１２と同義であり、Ｒ^８は上記一般式（１−２）におけるＲ^２１及びＲ^２２と同義である。］ Examples of the terminal unsaturated carboxylic acid include compounds represented by the following general formula (4).

[In Formula (4), R ⁷ has the same meaning as R ¹¹ and R ¹² in General Formula 1-1, and R ⁸ has the same meaning as R ²¹ and R ²² in General Formula 1-2. . ]

  Examples of the compound represented by the formula (4) include acrylic acid, methacrylic acid, 3-butenoic acid, 4-pentenoic acid, 5-hexenoic acid, 6-heptenoic acid, 7-octenoic acid, 8-nonenoic acid, Examples include 9-decenoic acid, 10-undecenoic acid, and 3-allyloxypropionic acid. Among these, acrylic acid and methacrylic acid are preferable from the viewpoint of achieving both a low viscosity of the coating agent and a self-restoring property and heat resistance of the formed resin cured film at a high level.

［式（５）中、Ａ^２１及びＡ^２２はそれぞれ独立に炭素数２〜４のアルキレン基を表し、ｄ１及びｄ２はそれぞれ独立に０〜２５の整数を表し、Ｒ^８１及びＲ^８２はそれぞれ独立に単結合又は炭素数１〜６のアルキレン基を表し、ｅは１０〜５００の整数を表す。］ As the component (C), a compound represented by the following general formula (5) is preferable from the viewpoint of achieving both low viscosity of the coating agent and heat resistance of the formed resin cured film at a high level.

[In Formula (5), A ²¹ and A ²² each independently represent an alkylene group having 2 to 4 carbon atoms, d 1 and d 2 each independently represent an integer of 0 to 25, and R ⁸¹ and R ⁸² are each independently Represents a single bond or an alkylene group having 1 to 6 carbon atoms, and e represents an integer of 10 to 500. ]

Examples of A ²¹ and A ²² include an ethylene group and a propylene group, and an ethylene group is preferable from the viewpoint of achieving both low viscosity of the coating agent and heat resistance of the formed resin cured film at a high level.

D1 and d2 in the formula (5) are 0 (that is,-(A ²¹ O)-and-from the viewpoint of achieving both low viscosity of the coating agent and heat resistance of the formed resin cured film at a high level. ^{(OA 22)} - is preferably a single bond) to 15, 0 being more preferred.

R ⁸¹ and R ⁸² in the formula (5) are each a single bond or an alkylene having 1 to 3 carbon atoms from the viewpoint of achieving both low viscosity of the coating agent and heat resistance of the formed resin cured film at a high level. Group is preferable, and an alkylene group having 1 to 3 carbon atoms is more preferable.

When R ⁸¹ and R ⁸² are alkylene groups having 1 to 6 carbon atoms, examples include methylene group, ethylene group, propylene group, trimethylene group, n-butylene group, n-pentylene group, and n-hexylene group. .

  E in Formula (5) is preferably 15 to 100, and more preferably 15 to 50, from the viewpoint of achieving both low viscosity of the coating agent and heat resistance of the formed resin cured film at a high level.

  The component (D) is represented by (D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) the general formula (2). And at least one compound selected from the group consisting of hydroxyalkyl (meth) acrylates.

  Examples of the component (D1) include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-heptanediol, neopentyl glycol, 1,6-hexanediol, and 3-methyl. -Alkanediols such as 1,5-pentanediol, diols having ether groups such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedi And cycloalkanediols such as methanol. From the viewpoint that the self-healing property of the formed resin cured film is more excellent, alkanediol and diol having an ether group are preferable, and alkanediol having 2 to 6 carbon atoms is more preferable.

Examples of the anionic hydrophilic group in the component (D2) include a carboxy group (—COOH), a carboxylate group (—COO ⁻ ), a sulfo group (—SO ₃ H), and a sulfonate group (—SO ₃ ⁻ ). From the viewpoint that the resulting curable resin is more excellent in emulsifiability in hydrophilic solvents such as alcohol, ketone and acetate, water and the like, a carboxy group and a carboxylate group are preferable.

  Examples of the component (D2) include C2-C8 carboxyl groups such as 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2'-dimethylolpentanoic acid, and salts thereof. And / or a carboxylate group-containing compound, 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, dicarboxylic acids such as 5- [4-sulfophenoxy] isophthalic acid and salts thereof, ethylene glycol, propylene glycol, Examples thereof include a sulfo group and / or a sulfonate group-containing polyester polyol obtained by reacting with a low molecular weight polyol such as 1,4-butanediol, 1,6-hexanediol, or neopentyl glycol. These can be used individually by 1 type or in combination of 2 or more types. Moreover, the polyester polyol which has a pendant type carboxyl group obtained by making diol which has a carboxyl group, aromatic dicarboxylic acid, fatty acid dicarboxylic acid, etc. react, or its salt is also mentioned as (D2) component. Further, it may be obtained by further mixing and reacting a diol having no carboxyl group during the above reaction. 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid are preferred from the viewpoint that the resulting curable resin is more excellent in emulsifiability in the hydrophilic solvent and water.

As the component (D3), R ⁵ in the general formula (2) is preferably a hydrogen atom from the viewpoint that the cured resin film to be formed has better self-healing properties.

R ⁶ in the general formula (2) may be a linear or branched alkylene group having 2 to 10 carbon atoms, such as a methylene group, an ethylene group, a propylene group, a trimethylene group, n -Butylene group, n-pentylene group, n-hexylene group, n-heptylene group, n-octylene group, etc. are mentioned. R ⁶ is preferably an alkylene group having 2 to 6 carbon atoms from the viewpoint that the self-healing property of the cured resin film to be formed is more excellent. Examples of such hydroxyalkyl (meth) acrylates include hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, and 6-hydroxyhexyl acrylate.

  The component (D) preferably contains at least (D1) a diol compound having 2 to 13 carbon atoms from the viewpoint that the cured resin film to be formed is more excellent in self-repairability. Moreover, from the viewpoint that the emulsifiability of the obtained curable resin in the hydrophilic solvent or water is more excellent, it is preferable to include a compound having at least (D2) an anionic hydrophilic group and at least two active hydrogens. .

  The coating agent of this embodiment comprises the step of reacting the isocyanate group-terminated prepolymer obtained by reacting the component (A), the component (B), and the component (C) with the component (D). It can obtain by the manufacturing method provided.

  In the method of this embodiment, the (A) component, the (B) component, and the (C) component are reacted to obtain an isocyanate group-terminated prepolymer, and then the above-mentioned (D) component is reacted with the isocyanate group-terminated prepolymer. be able to.

  When the isocyanate group-terminated prepolymer is produced, the component (A), the component (B) and the component (C) are combined with the component (A) with respect to the number of hydroxy groups derived from the component (B) and the component (C). It is preferable to make it react by the compounding quantity that the number of the isocyanate group derived from becomes excess.

  From the viewpoint that the self-healing property of the cured resin film to be formed is more excellent, the component (A), the component (B) and the component (C) are composed of an isocyanate group derived from the component (A), the component (B) and the component (C). ) It is preferable to make it react so that the molar ratio with the hydroxy group derived from a component may become isocyanate group: hydroxy group = 100: 50-100: 95, and it is made to react so that it may become 100: 70-100: 90. Is more preferable.

  The blending ratio of the component (B) and the component (C) is a molar ratio of the component (B) from the viewpoint of achieving both low viscosity of the coating agent and self-healing property of the cured resin film to be formed at a high level. Component (C) is preferably 1: 9 to 9: 1, more preferably 3: 7 to 8: 2, and still more preferably 5: 5 to 7: 3.

  As reaction temperature, 40-150 degreeC is suitable, and you may add a catalyst as needed. Examples of the catalyst include carboxylic acid metal salts (potassium, tin, bismuth, etc.), and specific examples include dibutyltin dilaurate, stannous octoate, dibutyltin-2-ethylhexanoate, and the like. As a compounding quantity of a catalyst, 0.001-0.1 mass% is suitable with respect to the total mass of a reaction material (for example, (A) component, (B) component, and (C) component), 0.005 -0.03 mass% is more suitable. Further, an organic solvent or a diluent that does not react with the isocyanate group can be added during or after the reaction.

  As the organic solvent, for example, acetone, methyl ethyl ketone, toluene, tetrahydrofuran, dioxane, dimethylformamide, N-methylpyrrolidone and the like can be used.

  Examples of the diluent include ethylenically unsaturated monomers such as esters of C1-C12 alcohols or polyhydric alcohols with (meth) acrylic acid, styrene, α-methylstyrene, (meth) acrylic acid amide. Is mentioned. Among these, the ester or styrene is preferable.

  Next, (D) component can be made to react with the isocyanate group terminal prepolymer obtained by said reaction. As the component (D), the components (D1) to (D3) may be used alone or in combination of two or three. In each of the components (D1) to (D3), a plurality of compounds can be used in combination. From the viewpoint that the cured resin film to be formed is more excellent in self-healing properties, it is preferable to use the component (D1). Moreover, it is preferable to use (D2) component from a viewpoint that the emulsifiability to the said hydrophilic solvent, water, etc. of the curable resin obtained is more excellent.

  About the compounding quantity of (D1) component-(D3) component in (D) component, from the viewpoint that the self-repair property of the resin cured film formed is more excellent, (D1) with respect to the total number of moles of (D) component. ) Component is preferably 50 to 100 mol%, more preferably 80 to 100 mol%, (D2) component is preferably 0 to 50 mol%, more preferably 0 to 20 mol%, and (D3) component is 0 to 50 mol%. The mol% is preferable, and 0 to 20 mol% is more preferable. Moreover, when mix | blending (D2) component, an anionic hydrophilic group is 0.00 with respect to the obtained curable resin from a viewpoint that the emulsifiability to the said hydrophilic solvent, water, etc. of the obtained curable resin is more excellent. It is preferable to adjust so that it may be contained in the amount of 05-5.0 mass%, and it is more preferable to adjust so that it may be included in the amount of 0.1-3.0 mass%.

  Moreover, you may make a low molecular weight compound react with an isocyanate group terminal prepolymer in the range which does not impair the effect of this invention. The low molecular weight compound preferably has a molecular weight of 400 or less, more preferably 300 or less. Examples of such low molecular weight compounds include trimethylolpropane, pentaerythritol, sorbitol and other trivalent or higher molecular weight alcohols, ethylenediamine, propylenediamine, hexamethylenediamine, diaminocyclohexylmethane, piperazine, 2-methylpiperazine, isophorone. Low molecular weight polyamines such as diamine, diethylenetriamine, and triethylenetetramine are listed.

  As a compounding quantity of (D) component and a low molecular weight compound in said case, the quantity in which the isocyanate group of an isocyanate group terminal prepolymer does not remain is preferable. For example, the amount of isocyanate group in the isocyanate group-terminated prepolymer is measured by a technique such as titration, and the amount of the isocyanate group in the component (D) and the low molecular weight compound that can react with the isocyanate group is measured. The blending amount of the component (D) and the low molecular weight compound can be set so as to be equivalent to or more, preferably more than equivalent and 1.2 times equivalent or less.

  The reaction between the isocyanate group-terminated prepolymer, the component (D) and, if necessary, the low molecular weight compound can be carried out, for example, at a temperature of 20 to 100 ° C., and is preferably continued until no isocyanate group remains. The residual isocyanate group can be confirmed by titration or peak observation derived from the isocyanate group in IR.

  As a weight average molecular weight of curable resin, 3000-150,000 is mentioned, for example, and 5000-80000 are preferable from a viewpoint that a handleability is more excellent. The average molecular weight of the curable resin can be adjusted, for example, by adjusting the molar ratio of the usage amounts of the component (A), the component (B), the component (C), and the component (D). In addition, the average molecular weight of curable resin can be calculated | required by the polyethylene glycol conversion method or the polystyrene conversion method, for example using gel permeation chromatography (GPC).

  The coating agent of the present embodiment contains a curable resin obtained by the above-described reaction (hereinafter sometimes referred to as the curable resin of the present embodiment). Although content of the curable resin of this embodiment in a coating agent can be suitably adjusted with a use, for example, 30 mass% or more is preferable on the basis of coating agent whole quantity, 50 mass% or more is more preferable, 85 mass% The above is more preferable.

  In the coating agent of this embodiment, the curable resin obtained by the above-described reaction may be used as it is, or other components may be blended to form a coating agent. Examples of other components include a polymerization initiator, a photosensitizer, a curing accelerator, an organic solvent for adjusting the viscosity, and a reactive diluent, although they vary depending on the application of the coating agent. The coating agent of this embodiment preferably contains a polymerization initiator. In addition, the component which accelerates | stimulates polymerization reaction of curable resin, such as a polymerization initiator, a photosensitizer, and a hardening accelerator, can prevent generation | occurrence | production of the pot life by the storage stability of the coating agent of this embodiment falling. From the viewpoint of the above, it is preferable that the coating agent is blended immediately before the coating agent is applied to the substrate or the like.

  A polymerization initiator is contained in order to accelerate the polymerization reaction of the curable resin. Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator that generates radicals by light. It is preferable to use a photopolymerization initiator from the viewpoint that it can be used for a substrate having low heat resistance (for example, a plastic film).

  Examples of the photopolymerization initiator include 2,2-diethoxyacetophenone, benzophenone, p-methoxybenzophenone, benzoylmethyl ether, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, acetophenone, propionphenone, xanthone, benzoylgi. Acid methyl, benzyl, naphthoquinone, 4-methylacetophenone, anthraquinone, t-butyl perbenzoate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2- Morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1 -Hydroxycyclo Cyclohexyl phenyl ketone, 3,6-bis (2-morpholino isobutyl) -9-butyl-carbazole, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl phosphine oxide, thioxanthone derivatives, and the like. Among these, from the viewpoint of curing speed, benzophenone, methyl benzoylformate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone and 2-hydroxy-2-methyl-1-phenylpropan-1-one Is preferred. These photoinitiators may be used individually by 1 type, and may use 2 or more types together. In the present embodiment, a photosensitizer can be used in combination. Examples of the photosensitizer include mono-, di- or triethanolamine, N-methyldiethanolamine, alkyl 4-dimethylaminobenzoate (alkyl group having 1 to 3 carbon atoms), 4-dimethylaminoacetophenone, and the like.

  Examples of the thermal polymerization initiator include known organic peroxides and azo compounds. Examples of the organic peroxide include ketone peroxide, peroxyketal, hydroperoxide (cumene hydroperoxide, etc.), diallyl peroxide, diacyl peroxide (benzoyl peroxide, lauroyl peroxide, etc.), peroxyester ( t-butylperoxy-2-ethylhexanoate), peroxydicarbonate, potassium persulfate, hydrogen peroxide, and the like. Examples of the azo compound include 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2′-azobis (2-methyl) propionate, 2,2'-azobis (isobutyric acid) dimethyl, 4,4'-azobis (4-cyanopentanoic acid), 2,2'-azobis (2-amidinopropane) dihydrochloride, and 2,2'-azobis {2 -Methyl-N- [2- (1-hydroxybutyl)]-propionamide}, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] and the like. Among these, 2,2'-azobis (isobutyronitrile) and dimethyl 2,2'-azobis (2-methyl) propionate are preferable from the viewpoint of curing speed. These thermal polymerization initiators may be used alone or in combination of two or more.

  As content of the polymerization initiator in a coating agent, 10 mass parts or less are preferable with respect to 100 mass parts of curable resin of this embodiment, and 5 mass parts or less are more preferable.

  Examples of the curing accelerator include cobalt naphthenate, dimethylaniline, and acetylacetone.

  Examples of the organic solvent include methyl ethyl ketone, methyl isobutyl ketone, toluene, butyl acetate, methoxypropanol, methoxypropyl acetate, methobuta (3-methoxybutanol), 3-methoxybutyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether. , Diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate and the like.

  Examples of reactive diluents include styrene monomers, dienes, acrylic monomers, vinyl compounds, unsaturated dicarboxylic acid diesters, and imide compounds.

  Examples of styrene monomers include styrene derivatives substituted with styrene, alkyl, nitro, cyano, halogen, and the like, divinylbenzene, and the like.

  Examples of dienes include butadiene, 2,3-dimethylbutadiene, isoprene, chloroprene and the like.

  Examples of acrylic monomers include acrylic acid having a branched or straight chain alkyl group having 1 to 18 carbon atoms, acrylic acid having a bicyclic hydrocarbon group having 5 to 10 carbon atoms, and aromatic carbonization having 6 to 14 carbon atoms. Acrylic acid having a hydrogen group, an alkylene oxide adduct of acrylic acid having an aromatic hydrocarbon group having 6 to 14 carbon atoms, an acrylate ester of benzyl alcohol (or its alkylene oxide (1 to 5 mol) adduct), acrylic Allyl acid, propargyl acrylate, piperonyl acrylate, salicyl acrylate, furyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, pyranyl acrylate, phenethyl acrylate, cresyl acrylate, triphenylmethyl acrylate, cumyl acrylate Acrylic acid 3- (N, N-dimethylamino) ) Addition of propyl, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 1,6-hexanediol diacrylate, tricyclodecanediol diacrylate, trimethylolpropane (or its alkylene oxide (1-15 mol)) Product) triacrylic ester, pentaerythritol (or its alkylene oxide (1-15 mol) adduct), triacrylic ester, pentaerythritol (or its alkylene oxide (1-20 mol) adduct) tetraacrylic acid Esters, tetraacrylic acid ester of ditrimethylolpropane (or its adduct of alkylene oxide (1 to 20 mol)), hexaacrylic acid ester of dipentaerythritol (or its adduct of alkylene oxide (1 to 30 mol)) Acrylate, acrylic acid esters such as 1,1,1-trifluoroethyl acrylate, perfluoroethyl acrylate, perfluoro-n-propyl acrylate, perfluoro-i-propyl acrylate; Acrylic acid such as acrylic acid N, N-dimethylamide, acrylic acid N, N-diethylamide, acrylic acid N, N-dipropylamide, acrylic acid N, N-di-i-propylamide, acrylic acid anthracenylamide Amides; acrylic acid anilide, acryloylnitrile, acrolein and the like.

  Examples of the vinyl compound include vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N-vinyl pyrrolidone, vinyl pyridine, vinyl acetate and the like.

  Examples of the unsaturated dicarboxylic acid diester include diethyl citraconic acid, diethyl maleate, diethyl fumarate, diethyl itaconate and the like.

  Examples of the imide compound include monomaleimide compounds such as N-phenylmaleimide, N-cyclohexylmaleimide, N-laurylmaleimide, N- (4-hydroxyphenyl) maleimide, and N-acryloylphthalimide.

  Among these, from the viewpoints of compatibility with the curable resin of the present embodiment, vapor pressure, skin irritation, and low viscosity of the resin composition, acrylic acid of benzyl alcohol (or its adduct of alkylene oxide (1 to 5 mol)). Acid ester, 1,6-hexanediol diacrylate, tricyclodecanediol diacrylate, trimethylolpropane (or its adduct of alkylene oxide (1 to 15 mol)), pentaerythritol (or its alkylene oxide ( 1-15 mol) adduct) triacrylate ester, pentaerythritol (or its alkylene oxide (1-20 mol) adduct) tetraacrylate ester, ditrimethylolpropane (or its alkylene oxide (1-20 mol)) Additive) Tetraacrylic acid Este , Hexa acrylate esters of dipentaerythritol (or alkylene oxide (1 to 30 mol) adduct), styrene is preferred.

  A reactive diluent may be used individually by 1 type, and 2 or more types can also be mixed and used for it.

  The coating agent of the present embodiment may contain additives other than the components described above within a range not impairing the effects of the present invention, depending on the application. Examples of such additives include leveling agents, plasticizers, antifoaming agents, ultraviolet absorbers, antioxidants, viscosity control agents, and the like.

  The coating agent of this embodiment preferably has a viscosity at 20 ° C. of less than 1000 mPa · s, more preferably 800 mPa · s or less, and even more preferably 500 mPa · s or less. In addition, the said viscosity means the value measured using the B-type viscometer (No. 4 rotor, 60 rpm). In the present embodiment, it is preferable that the viscosity condition is satisfied when the content of the curable resin of the present embodiment in the coating agent is 30% by mass or more based on the total amount of the coating agent.

  The coating agent of the present embodiment includes, for example, a coating agent for forming a protective layer of an optical material such as a color filter that requires transparency, a clear paint applied to the body of an automobile, a top coat agent for protecting the surface of a plastic film, It can be used as a coating agent for protecting plastic parts or a coating agent used for thermoforming such as vacuum forming or in-mold forming by top-coating a plastic film.

  Next, the cured resin film according to the present invention will be described. The cured resin film according to the present invention is obtained by curing the coating agent of the present embodiment, and can be formed, for example, by curing a curable resin in the coating agent by a radical polymerization reaction.

  The cured resin film of the present embodiment can be formed by curing the coating film of the coating agent of the present embodiment provided on the substrate.

  The substrate is not particularly limited, and examples thereof include metal products such as automobiles, plastic products such as films and molded products, glass products such as optical materials, wood products such as furniture, and paper. Moreover, in order to improve the adhesiveness of the resin cured film to the base material, an undercoat layer or the like may be provided in advance on the base material.

  The coating film of the coating agent can be obtained by applying the coating agent of the present embodiment to a substrate or the like. The application method is not particularly limited. For example, spin coating, brush coating, spraying (spraying), dip coating, blade coating, roll coating, ink jet printing, gravure printing, screen printing, flexographic printing, Known methods such as a bar coating method and a die coating method may be used. Moreover, you may perform a drying process as needed after application | coating. It does not specifically limit as drying conditions, Although it can select suitably according to the kind, quantity, etc. of the organic solvent contained in a coating agent, For example, the conditions of 1 to 60 minutes at 60-200 degreeC are mentioned.

  The thickness of the coating varies depending on the use of the cured resin film and is not particularly limited. For example, the thickness of the formed cured resin film can be set to be 1 to 100 μm and be 3 to 40 μm. It is preferable to set.

  The method for curing the coating film of the coating agent is not particularly limited, and the coating film may be allowed to cure at room temperature and normal pressure. The coating film may be heated, pressurized, or irradiated with active energy rays. It may be applied and cured. From the viewpoint that the curing time is shorter, it is preferable to apply heating, pressurization, active energy ray irradiation and the like, and from the viewpoint that it can be applied to a substrate having low heat resistance, it is preferable to apply active energy ray irradiation. In this embodiment, for example, the cured resin film may be formed by curing a curable resin in the coating agent by a radical polymerization reaction.

  Examples of active energy rays include visible light, infrared rays, ultraviolet rays, X-rays, α rays, β rays, γ rays, and electron beams. Of these, ultraviolet rays and electron beams are preferable from the viewpoints of safety and reaction efficiency.

The irradiation condition of the active energy ray can be appropriately selected depending on the type of the active energy ray. For example, as a preferable irradiation condition of ultraviolet rays, the illuminance is 1 to 1000 mW / cm ² , and the irradiation amount is 0.1 to 10,000 mJ / cm. ² is mentioned.

  As an active energy ray irradiation device, for example, a lamp light source such as a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, or an excimer lamp, a pulse such as an argon ion laser or a helium neon laser, a continuous laser light source, or an LED light source is used. be able to.

  Although the temperature in the case of heating can be suitably adjusted with the base material, the kind of polymerization initiator in a coating agent, etc., 40-200 degreeC is mentioned.

  The laminated body which concerns on this invention is equipped with a base material and the resin cured film of this embodiment provided on the base material. Examples of the substrate include those described above.

  The cured resin film of the present embodiment may be provided in a form included in the coating layer provided on the substrate. In the laminate of this embodiment, the coating layer containing the cured resin film of this embodiment may be disposed on the base material, and other layers are disposed between the base material and the coating layer. May be.

  The thickness of the cured resin film of the present embodiment varies depending on the application and is not particularly limited. For example, 1 to 100 μm is preferable, and 3 to 40 μm is more preferable.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited to these examples.

<Manufacture of coating agent and resin cured film>
Example 1
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, an air gas introduction pipe and a dropping funnel, 680 parts by mass (2 mol) of a bisphenol A type epoxy compound represented by the following formula (i), an addition reaction catalyst 5 parts by weight of triphenylphosphine and 1 part by weight of methylhydroquinone as a radical polymerization inhibitor were added. 296 mass parts (4.1 mol) of acrylic acid was dripped here, it was made to react at 110 degreeC, and the compound B-1 represented by following formula (ii) was obtained.

［式（ｉｉｉ）中、ｅ１は１８〜２８の整数を表す。］ 22.6 parts by mass of compound B-1 represented by formula (ii), 7.9 parts by mass of hexamethylene diisocyanate, 10.4 parts by mass of isophorone diisocyanate, both represented by the following formula (5-1) 56 parts by mass of polydimethylsiloxane having a hydroxyl group at the terminal (weight average molecular weight 2000) (hereinafter referred to as “hydroxyl-terminated polysiloxane (molecular weight 2000)”), 100 parts by mass of methyl ethyl ketone, urethane reaction catalyst (Nitto Kasei Co., Ltd.) ) Made by the company, product name: Neostan U-600 (bismuth catalyst) and 0.1 part by mass of radical polymerization inhibitor (methylhydroquinone) are mixed and reacted at 80 ° C. , 4-butanediol was added in an amount of 1.8 parts by mass and reacted until the isocyanate group disappeared to obtain a methyl ethyl ketone solution of a curable resin. 5 g of the obtained methyl ethyl ketone solution was placed in a petri dish, and the curable resin concentration of the methyl ethyl ketone solution was calculated from the residue after leaving it in a dryer at 105 ° C. for 3 hours.

[In formula (iii), e1 represents an integer of 18 to 28. ]

  To the solution obtained above, 1-hydroxycyclohexyl phenyl ketone as a photopolymerization initiator was mixed at a ratio of 2 parts by mass with respect to 40 parts by mass of the curable resin to obtain a coating agent.

The obtained coating agent was applied onto a polyester film using an applicator and dried at 80 ° C. for 10 minutes to form a coating film having a thickness of about 100 μm. Next, the coating film was irradiated with ultraviolet rays (UVC waves) at an irradiation amount of 500 mJ / cm ² to obtain a cured resin film.

(Examples 2 to 11 and Comparative Examples 1 to 7)
A coating agent and a cured resin film were obtained in the same manner as in Example 1 except that the raw material composition was changed as shown in Tables 1 to 5.

  In addition, the following notation in a table | surface is demonstrated below.

“B-2”: a compound represented by the following formula (v) produced by the following procedure.

  In a reaction vessel equipped with a stirrer, thermometer, reflux condenser, air gas introduction pipe and dropping funnel, 1816 parts by mass of bisphenol A type epoxy compound represented by the following formula (iv), triphenylphosphine as an addition reaction catalyst 10 parts by mass and 2 parts by mass of methylhydroquinone as a radical polymerization inhibitor were added. 296 mass parts of acrylic acid was dripped here, it was made to react at 110 degreeC, and the compound B-2 represented by following formula (v) was obtained.

［式（ｖｉ）中、ｅ２は２８〜３８の整数を表す。］ “Hydroxyl terminal polysiloxane (molecular weight 3200)”: polydimethylsiloxane having a hydroxy group at both ends (weight average molecular weight 3200) represented by the following formula (5-2).

[In the formula (vi), e2 represents an integer of 28 to 38. ]

［式（５−３）中、ｅ３は２３〜３３の整数を表す。］ “Hydroxyl terminal polysiloxane-2 (molecular weight 3200)”: Polydimethylsiloxane (weight average molecular weight 3200) having hydroxy groups at both ends represented by the following general formula (5-3).

[In formula (5-3), e3 represents an integer of 23 to 33. ]

“B ′”: a compound represented by the following formula (vii).

“PCD (molecular weight 2000)”: Polycarbonate diol (number average molecular weight 2000) (manufactured by Asahi Chemicals Corporation, Duranol T6002).

“PPG (molecular weight 2000)”: polypropylene glycol (weight average molecular weight 2000).

“PTG (molecular weight 2000)”: polytetramethylene glycol (weight average molecular weight 2000).

[viscosity]
About the methyl ethyl ketone solution of the curable resin obtained in Examples and Comparative Examples (the solid content concentration of the curable resin is 50% by mass), the solution is set to 20 ° C., and a B-type viscometer (No. 4 rotor, 60 rpm) is used. The viscosity was measured. The results are shown in Tables 1-4. When the viscosity exceeds 1000 mPa · s, handling becomes difficult.

[Evaluation of self-healing]
The cured resin obtained in the examples and comparative examples was subjected to a rubbing treatment in the same place three times in one direction with a load of 100 g / cm ² with a brass brush. The haze value of the place subjected to the rubbing treatment was measured using a fully automatic direct reading haze computer HGM-2DP (manufactured by Suga Test Instruments Co., Ltd.) before and after being left to stand for 1 day after the rubbing treatment. The difference was calculated. The results are shown in Tables 1-4. If the difference is 4.5 or less, the self-repairing property is excellent.

  In the cured resin products of the examples, the scratches due to the rubbing treatment were repaired so that they could not be visually confirmed in 3 minutes after the rubbing treatment. However, in the cured products of the comparative examples, the haze value could be measured after the rubbing treatment. In some cases, it took 1 day until the wound was repaired.

[Evaluation of heat resistance]
One drop of the coating agent obtained in Examples and Comparative Examples was dropped on a polypropylene film, dried at 80 ° C. for 10 minutes, and then irradiated with ultraviolet rays (UVC waves) at an irradiation amount of 500 mJ / cm ² to obtain a cured resin. The obtained resin cured product was subjected to differential thermogravimetric analysis. The measurement method was to measure the weight loss of the cured resin when the temperature was raised from room temperature to 400 ° C. at a rate of temperature increase of 10 ° C./min while injecting air at 50 ml / min. Was measured. The results are shown in Tables 1-4. If temperature is 270 degreeC or more, it shows that heat resistance is excellent.

  As shown in Tables 1 to 3, the coating agents of Examples 1 to 11 have a sufficiently low viscosity and excellent handling properties even when the content of the curable resin is 50% by mass, and self-repair. It was confirmed that a cured resin film excellent in heat resistance and heat resistance can be formed. On the other hand, in the comparative example, it is impossible to simultaneously achieve that the coating agent has a sufficiently low viscosity and that the formed resin cured film has excellent self-healing property and heat resistance.

  According to the present invention, the coating agent can have a sufficiently low viscosity even when the concentration of the curable resin is sufficiently increased, and can form a cured resin film excellent in self-repairability and heat resistance, A cured resin film formed of a coating agent and a laminate including the same can be provided. According to the coating agent of the present invention, a cured resin film having excellent self-repairing properties and heat resistance can be formed without heating. The coating agent of the present invention can have a viscosity excellent in coating processability (particularly, operability such as application to a substrate, etc.) and suppress the occurrence of uneven coating and wrinkles on a cured resin film. be able to. The coating agent of the present invention is, for example, a coating agent for forming a protective layer of an optical material such as a color filter that requires transparency, a clear paint applied to the body of an automobile, a top coating agent for protecting the surface of a plastic film, It can be used as a coating agent for protecting plastic parts or a coating agent used for thermoforming such as vacuum forming or in-mold forming by top-coating a plastic film.

Claims (3)

An isocyanate group-terminated prepolymer obtained by reacting (A) a polyisocyanate, (B) a compound represented by the following general formula (1-1), and (C) a polysiloxane having at least two hydroxy groups; ,
(D1) a diol compound having 2 to 13 carbon atoms, (D2) a compound having an anionic hydrophilic group and at least two active hydrogens, and (D3) a hydroxyalkyl (meth) represented by the following general formula (2) At least one compound selected from the group consisting of acrylates;
A coating agent containing a curable resin, obtained by reacting the above.

[In Formula (1-1), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and R ²¹ and R ²² each independently represent a carbon number 1 to 1 that may contain a single bond or an ether bond. 12 represents an alkylene group, X represents a divalent group represented by the following general formula (1-2),

{Wherein ^{(1-2), A 11} and ^{A 12} represents an alkylene group having 2 to 4 carbon atoms each ^{independently, R 31} and ^{R 32} each independently represents an alkyl group having 1 to 3 carbon atoms, a phenyl group or Represents a halogeno group, R ⁴ represents a single bond, —CR ⁵ ₂ — (wherein R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a phenyl group) or —SO ₂ —. B1 and b2 each independently represent an integer of 0 to 2, and c1 and c2 each independently represent an integer of 0 to 10. }
a represents an integer of 1 to 10. ]

Wherein (2), ^{R 5} represents a hydrogen atom or a methyl group, ^{R 6} represents an alkylene group having 2 to 10 carbon atoms. ]   A cured resin film obtained by curing the coating agent according to claim 1.   A laminate comprising a substrate and the cured resin film according to claim 2 provided on the substrate.