JP2018165354A - Curable composition and cured film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable composition providing a cured product which has high storage stability, has high adhesion to a base material, is excellent in curability even in the case of ultraviolet rays like an LED light source with a small total amount of energy, and has high surface hardness.SOLUTION: A curable composition contains a monomer (A) which has an ethylenic polymerizable group (a) and does not have an acidic functional group (b) and a thiol group (c) and a compound (B1) which has the acidic functional group (b) and the thiol group (c) and does not have the ethylenic polymerizable group (a), or contains a compound (B2) which has the ethylenic polymerizable group (a), the acidic functional group (b) and the thiol group (c).SELECTED DRAWING: None

Description

  The present invention relates to a curable composition.

  Conventionally, display devices such as liquid crystal displays (LCD) and touch panel displays provided with a plastic film with a hard coat coating as a protective layer on the surface, and electronic elements such as polarizers, optical fibers and optical disks in LCDs are known. In addition, hard coat coatings are used for surface protection purposes such as prevention of surface scratches and dust adhesion. In recent years, electronic devices including a touch panel that is operated by directly touching a screen with a finger, a pen, or the like such as smartphones and tablet terminals are remarkably widespread, and such devices are required to further improve the hardness of the touch panel surface.

  While the hardness is improved, there is an increasing demand for a curable composition that can be cured by an ultraviolet irradiation device using an LED light source. An ultraviolet irradiation device using an LED light source has low power consumption and generates less ozone. Therefore, there is an advantage that the running cost and the influence on the natural environment can be reduced.

However, since the LED light source has a single wavelength, the total amount of ultraviolet energy is small compared to ultraviolet lamp light sources such as high-pressure mercury lamps, ultra-high pressure mercury lamps, and metal halide lamps that emit ultraviolet light of a wide wavelength, and is generated from a photopolymerization initiator. Since the amount of radicals to be generated is small, the curability is lowered in the conventional curable composition, and the resin strength after curing is lowered.
Therefore, the curable composition is required to have high curability so that curability can be exhibited even when the total amount of energy as in the LED light source is small.

In general, as a measure for enhancing the surface protection function of a hard coat coating film, a method of blending a hard inorganic filler into a curable composition to form a hard coat layer is known (for example, Patent Document 1). However, in this composition, the curability with an LED light source is poor, and the hardness decreases.
Moreover, as a composition which improves sclerosis | hardenability, the hard-coat coating liquid containing 5 to 50weight% of the polythiol compound which has the monomer or oligomer which has an acrylate as a main component, and two or more thiol groups is known (for example, Patent Document 2). However, since this composition has poor storage stability, it thickens during storage at room temperature.

JP 2009-90523 A JP 2012-197383 A

  The present invention has high storage stability, high adhesion to a base material, and curability that provides a cured product having excellent surface curability and high surface hardness even in the case of ultraviolet light with a small total amount of energy such as an LED light source. An object is to provide a composition.

The inventors of the present invention have reached the present invention as a result of studies to achieve the above object.
That is, a monomer (A) having an ethylenically polymerizable group (a) and having neither an acidic functional group (b) nor a thiol group (c), an acidic functional group (b) and a thiol group (c) And a compound (B1) having no ethylenically polymerizable group (a) or having an ethylenically polymerizable group (a), an acidic functional group (b) and a thiol group (c) ( A curable composition containing B2); a cured film obtained by curing the curable composition.

  The curable composition of the present invention has high storage stability and excellent curability with an LED light source. Moreover, the hardened | cured material of the curable composition of this invention has the effect that the adhesiveness to a base material is high and surface hardness is high.

The curable composition of the present invention is the following composition of the first invention or the composition of the second invention.
In the first invention, the monomer (A) having an ethylenically polymerizable group (a) and having neither an acidic functional group (b) nor a thiol group (c), and an acidic functional group (b) And a compound (B1) having a thiol group (c) and not having an ethylenically polymerizable group (a).

  Moreover, 2nd invention of this invention is a curable composition containing the compound (B2) which has an ethylenically polymeric group (a), an acidic functional group (b), and a thiol group (c).

In the present specification, “(meth) acrylate” means “acrylate and / or methacrylate”, “(meth) acryloyl group” means “acryloyl group and / or methacryloyl group”, and “(meth) acryloyloxy group”. "Means" acryloyloxy group and / or methacryloyloxy group ".
Moreover, as said acidic functional group (b), a carboxy group, a phosphoric acid group, a sulfo group, etc. are mentioned.

First, the first invention will be described.
For the monomer (A) having an ethylenically polymerizable group (a), which is an essential component in the first invention, and having neither an acidic functional group (b) nor a thiol group (c) Examples of the ethylenic polymerizable group (a) possessed by (A) include a (meth) acryloyl group, an allyl group, a vinyl group, and a maleimide group.
Of these, the ethylenically polymerizable group (a) that is preferable from the viewpoint of curability is a (meth) acryloyl group, an allyl group, and a vinyl group, and more preferably a (meth) acryloyl group.

Examples of the monomer (A) include a (meth) acrylate monomer (A1) having a (meth) acryloyl group, an allyl monomer (A2) having an allyl group, a vinyl monomer (A3) having a vinyl group, and a monomer having a maleimide group. (A4) may be mentioned.
Of these, (A1), (A2) and (A3) are preferable from the viewpoint of curability, and (A1) is more preferable.
In the present invention, the vinyl monomer (A3) having a vinyl group does not include the allyl monomer (A2) having an allyl group.
The monomer (A) may be used alone or in combination of two or more.

The (meth) acrylate monomer (A1) having a (meth) acryloyl group is not particularly limited as long as it is a known (meth) acrylate, and is used as a monofunctional (meth) acrylate (A11), bifunctional (meta) ) Acrylate (A12), trifunctional (meth) acrylate (A13) and 4-6 functional (meth) acrylate (A14).
For example, bifunctional (meth) acrylate means that the number of (meth) acryloyl groups is two, and the same description method is used hereinafter.

  The monofunctional (meth) acrylate (A11) is a monoesterified product of an alcohol having 2 to 30 carbon atoms and (meth) acrylic acid [isobornyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, mono- (meth) acrylate of o-, m- or p-phenylphenol and mono (meth) acrylate of 3,3′-diphenyl-4,4′-dihydroxybiphenyl], alkylene oxide of alcohol having 2 to 30 carbon atoms Examples include monoesterified products (nonylphenoxypolyethylene glycol (meth) acrylate and the like) and (meth) acryloylmorpholine and the like of 1 to 30 mol of an adduct (2 to 4 carbon atoms of an alkylene group) and (meth) acrylic acid.

  Of (A11), preferred from the viewpoint of curability are (meth) acryloylmorpholine and phenoxyethyl (meth) acrylate.

  The bifunctional (meth) acrylate (A12) is a diesterified product of 1,2-hexanediol di (meth) having 2 to 30 carbon atoms (preferably 2 to 8 valences) and (meth) acrylic acid. Acrylates, etc.], a diesterified product of an alkylene oxide (2 to 4 carbon atoms of an alkylene group) of a polyhydric (preferably 2 to 8 valent) alcohol having 2 to 30 carbon atoms and an (meth) acrylic acid adduct. [Di (meth) acrylate of ethylene oxide adduct of bisphenol A, di (meth) acrylate of ethylene oxide adduct of bisphenolfluorene, etc.] and both-end epoxy (meth) acrylate having an OH group.

  Among (A12), from the viewpoint of hardness, a diesterified product [1,6-hexanediol di (meth) acrylate and the like] of a dihydric alcohol having 4 to 10 carbon atoms and (meth) acrylic acid is preferable.

  As the trifunctional (meth) acrylate (A13), a triesterified product of trivalent or higher (preferably 3 to 8 valent) alcohol having 3 to 30 carbon atoms and (meth) acrylic acid [tri (meth) acrylate of glycerin, Trimethylolpropane tri (meth) acrylate and pentaerythritol tri (meth) acrylate, etc.], and alkylene oxides of 3 to 30 carbon atoms (preferably 3 to 8 valences) of alcohols (carbon number of alkylene groups) 2-4) Triesterified products of 1-30 mol adduct and (meth) acrylic acid [tri (meth) acrylate of trimethylolpropane ethylene oxide adduct, etc.] and the like.

  As the tetra- to hexa-functional (meth) acrylate (A14), an esterified product of tetravalent or higher (having preferably 4 to 8) alcohol having 5 to 30 carbon atoms and (meth) acrylic acid [tetra (meth) of pentaerythritol]. Acrylate, penta (meth) acrylate of dipentaerythritol, hexa (meth) acrylate of dipentaerythritol, etc.], and alkylene oxide (alkylene group) of a tetravalent or more (preferably 4-8) valent alcohol having 5 to 30 carbon atoms (2-4) 1-30 mol adduct and esterified product of (meth) acrylic acid [dipentaerythritol ethylene oxide adduct tetra (meth) acrylate, dipentaerythritol ethylene oxide adduct penta ( Propylene of (meth) acrylate and dipentaerythritol Penta (meth) acrylate, etc.] or the like Kisaido adducts.

  Among (A13) and (A14), from the viewpoint of hardness, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta It is hexa (meth) acrylate of (meth) acrylate and dipentaerythritol.

  Examples of the allyl monomer (A2) having an allyl group include allyl glycidyl ether, trimethylolpropane diallyl ether, pentaerythritol triallyl ether, triallyl trimellitic acid and tetraallyl pyromellitic acid.

  Of (A2), preferred from the viewpoint of hardness are triallyl trimellitic acid and tetramellitic pyromellitic acid.

  Examples of the vinyl monomer (A3) having a vinyl group include N-vinyl pyrrolidone, N-vinyl caprolactam, 1,4-butanediol divinyl ether, cyclohexane dimethanol divinyl ether, and diethylene glycol divinyl ether.

  Among (A3), N-vinylcaprolactam, 1,4-butanediol divinyl ether, and cyclohexanedimethanol divinyl ether are preferable from the viewpoint of hardness.

  As the monomer (A4) having a maleimide group, N-phenylmaleimide, N-cyclohexylmaleimide, N-methylphenylmaleimide, N-naphthylmaleimide, N-hydroxyphenylmaleimide, N-methoxyphenylmaleimide, N-carboxyphenylmaleimide, N-nitrophenyl maleimide, N-benzyl maleimide and the like can be mentioned.

Of the compound (B1) having the acidic functional group (b) and the thiol group (c) and not having the ethylenic polymerizable group (a), the acidic functional group (b) has a carboxy group (b1). Compounds include mercapto organic acids [mercaptoaliphatic monocarboxylic acids (such as mercaptoacetic acid, mercaptopropionic acid, mercaptobutyric acid, mercaptosuccinic acid and dimercaptosuccinic acid), and mercapto aromatic monocarboxylic acids (such as mercaptobenzoic acid)] And a hydroxy organic acid [hydroxyacetic acid, lactic acid, malic acid, ascorbic acid and glycolic acid, and a compound having a carboxy group (b1) as the acidic functional group (b) among (B′2) described below [preferably ( (Meth) acrylic acid, etc.] and (meth) acrylate monomer having a hydroxy group as essential constituent monomers Radical polymerized product] and mercapto organic acid esterified product.
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].
Further, the esterified product with mercapto organic acid may be esterified with other organic acid (p-toluenesulfonic acid or the like) in addition to mercapto organic acid.

Among the compounds (B1), the compound having a phosphoric acid group (b2) as the acidic functional group (b) includes a phosphoric acid group (b2) as the acidic functional group (b) in the later-described (B′2). Esterified product of mercapto organic acid with a radical polymer comprising a compound having a thiophene [preferably 2- (meth) acryloyloxyethyl acid phosphate, etc.] and a (meth) acrylate monomer having a hydroxy group as essential constituent monomers Etc.
Examples of the (meth) acrylate monomer having a hydroxy group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 3-hydroxypropyl (meth) acrylate.
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].
The esterified product with the mercapto organic acid may be esterified with another organic acid (p-toluenesulfonic acid or the like) in addition to the mercapto organic acid.

  Said (B1) may be used individually by 1 type, or may use 2 or more types together.

  Among the compounds (B1), examples of the compound having a sulfo group (b3) as the acidic functional group (b) include mercaptoethanesulfonic acid and mercaptopropanesulfonic acid.

In the first invention, in addition to the monomer (A) and the compound (B1), an ethylenically polymerizable group (a), an acidic functional group (b) and a thiol group (c) described in detail below are added. Having compound (B2);
Compound (B ′) having an acidic functional group (b) and not having a thiol group (c);
You may contain the compound (C) which has a thiol group (c), and does not have any of ethylenically polymerizable group (a) and an acidic functional group (b) in the range which does not inhibit the effect of invention. .

Among the compounds (B2) having the ethylenically polymerizable group (a), acidic functional group (b) and thiol group (c), the compound having a carboxy group (b1) as the acidic functional group (b) Among (B′2) described later, a compound having a carboxy group (b1) as an acidic functional group (b) [preferably (meth) acrylic acid or the like] and a (meth) acrylate monomer having a hydroxy group are essential constituent units. Examples include a radical polymer obtained as a monomer, an esterified product of a mercapto organic acid, and a urethanized product of 2- (meth) acryloyloxyethyl isocyanate.
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].
The esterified product with the mercapto organic acid may be esterified with another organic acid (p-toluenesulfonic acid or the like) in addition to the mercapto organic acid.

Among the compounds (B2), the compound having a phosphoric acid group (b2) as the acidic functional group (b) includes a phosphoric acid group (b2) as the acidic functional group (b) in the later-described (B′2). A radical polymer comprising an essential constituent monomer of 2- (meth) acryloyloxyoxyethyl acid phosphate and the like, and a (meth) acrylate monomer having a hydroxy group, and a mercapto organic acid Examples include urethanized products of esterified products and 2- (meth) acryloyloxyethyl isocyanate.
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].
The esterified product with the mercapto organic acid may be esterified with another organic acid (p-toluenesulfonic acid or the like) in addition to the mercapto organic acid.

Among the compounds (B2), the compound having a sulfo group (b3) as the acidic functional group (b) has a sulfo group (b3) as the acidic functional group (b) in the later-described (B′2). Compound [preferably vinyl sulfonic acid and the like] and a radical polymer comprising a (meth) acrylate monomer having a hydroxy group as essential constituent monomers, an esterified product of mercapto organic acid, and 2- (meth) acryloyloxyethyl Examples thereof include urethanes with isocyanates.
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].
The esterified product with the mercapto organic acid may be esterified with another organic acid (p-toluenesulfonic acid or the like) in addition to the mercapto organic acid.

Said (B2) may be used individually by 1 type, or may use 2 or more types together.
The ethylenic polymerizable group (a) of the compound (B2) is preferably a (meth) acryloyl group and a vinyl group, and more preferably a (meth) acryloyl group, from the viewpoints of curability and hardness.

  The compound (B ′) having the acidic functional group (b) and not having the thiol group (c) has an acidic functional group (b), an ethylenically polymerizable group (a) and a thiol group ( Compound (B′1) not having any of c); Compound (B′2) having acidic functional group (b) and ethylenically polymerizable group (a) and not having thiol group (c) It is done.

Among the compounds (B′1) having the acidic functional group (b) and having neither the ethylenically polymerizable group (a) nor the thiol group (c), a carboxy group as the acidic functional group (b) As the compound having (b1), a C1-C30 monocarboxylic acid, a C2-C15 divalent to tetravalent polycarboxylic acid, and an acrylic polymer having a carboxy group [with a C3-30 carboxy group. And (meth) acrylic monomers [radical polymers having (meth) acrylic acid and the like] as essential constituent monomers.
The radical polymer containing a (meth) acrylic monomer having a carboxy group having 3 to 30 carbon atoms as an essential constituent monomer is copolymerized with other (meth) acrylate monomers [methyl (meth) acrylate, etc.]. It may be a thing.
Examples of the monocarboxylic acid having 1 to 30 carbon atoms include aliphatic monocarboxylic acids (formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, uraric acid, Myristic acid, stearic acid, behenic acid, glycolic acid, lactic acid, etc.), alicyclic monocarboxylic acid (cyclohexane carboxylic acid, etc.) and aromatic monocarboxylic acid (benzoic acid, cinnamic acid, naphthoic acid, salicylic acid, mandelic acid, etc.) ) And the like.
Examples of the divalent to tetravalent polycarboxylic acid having 2 to 15 carbon atoms include aliphatic polycarboxylic acids (such as oxalic acid, malonic acid, and thiodibropionic acid), and alicyclic polycarboxylic acids (1,4-cyclohexanedicarboxylic acid). Etc.) and aromatic polycarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, etc.).

Among the compounds (B′1), the compound having a phosphate group (b2) as the acidic functional group (b) may be a mono or dialkyl (alkyl group having 1 to 15 carbon atoms) phosphate ester [mono or dimethyl phosphorus Acid ester, mono or diethyl phosphate ester, mono or diisopropyl phosphate ester, mono or dibutyl phosphate ester, mono or di- (2-ethylhexyl) phosphate ester, and mono or diisodecyl phosphate ester] and phosphate groups Acrylic polymer [compound (B′2) having a phosphate group (b2) as an acidic functional group (b) [preferably 2- (meth) acryloyloxyethyl acid phosphate] is essential And the like, etc.].
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].

Among the compounds (B′1), the compound having a sulfo group (b3) as the acidic functional group (b) includes alkyl (C 1-15) benzenesulfonic acid (p-toluenesulfonic acid, nonylbenzenesulfonic acid). And dodecylbenzenesulfonic acid, etc.), sulfosalicylic acid, methanesulfonic acid, trifluoromethanesulfonic acid and acrylic polymer having sulfonic acid group [of compound (B′2), sulfo group (b3 ), And the like (preferably vinyl sulfonic acid) as a radical monomer, etc.].
The radical polymer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.].

  Among the compounds (B′2) having the acidic functional group (b) and the ethylenic polymerizable group (a) and not having the thiol group (c), a carboxy group (b1) as the acidic functional group (b). Examples of the compound having 3 to 30 carbon atoms include unsaturated monocarboxylic acids having 3 to 30 carbon atoms [(meth) acrylic acid, etc.], unsaturated polyvalent (2 to 4 valent) carboxylic acids having 4 to 30 carbon atoms [(anhydrous) maleic acid , Itaconic acid, fumaric acid, citraconic acid and the like], alkyl (alkyl group having 1 to 10 carbon atoms) ester of unsaturated polycarboxylic acid having 4 to 30 carbon atoms [monoalkyl maleate, monoalkyl ester of fumaric acid and Citraconic acid monoalkyl ester, etc.], succinic acid adduct of pentaerythritol tri (meth) acrylate, succinic acid adduct of dipentaerythritol penta (meth) acrylate, Taerythritol tri (meth) acrylate maleic acid adduct, dipentaerythritol penta (meth) acrylate maleic acid adduct, dipentaerythritol tetra (meth) acrylate dicarboxylic acid adduct, EO 6 mol addition pentaerythritol tri (meth) acrylate Maleic acid adduct, EO 10 mol addition dipentaerythritol penta (meth) acrylate cyclohexenyl carboxylic acid adduct, 2- (meth) acryloyloxyethyl-phthalic acid and the like.

  Among the compounds (B′2), examples of the compound having a phosphate group (b2) as the acidic functional group (b) include 2- (meth) acryloyloxyethyl acid phosphate, bis [2-[(meth) acryloyl]. Oxy] ethyl] phosphate, caprolactone-modified bis [2-[(meth) acryloyloxyethyl]] phosphate, caprolactone-modified [2-[(meth) acryloyloxyethyl]] acid phosphate, caprolactone-modified bis [2- [ (Meth) acryloyloxymethyl]] phosphate, caprolactone-modified bis [2-[(meth) acryloyloxypropyl]] phosphate, caprolactone-modified bis [2-[(meth) acryloyloxybutyl]] phosphate, etc. Can be mentioned.

  Among the compounds (B′2), compounds having a sulfo group (b3) as the acidic functional group (b) include vinyl sulfonic acid, Nt-butyl (meth) acrylamide sulfonic acid, and 2- (meth) acrylamide. -2-methylpropanesulfonic acid and the like.

Said (B ') may be used individually by 1 type, or may use 2 or more types together.
The ethylenic polymerizable group (a) of the compound (B′2) is preferably a (meth) acryloyl group and a vinyl group, and more preferably a (meth) acryloyl group, from the viewpoints of curability and hardness.

  As a compound having one thiol group (c) among the compounds (C) having the thiol group (c) and having neither the ethylenically polymerizable group (a) nor the acidic functional group (b) N-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, and the like.

  Among the compounds (C), as the compound having two thiol groups (c), 1,2-ethanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,5-pentanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol, 1,9-nonanedithiol, 2,3-dimercapto-1-propanol, dithioerythritol, 2,3-dimercaptosuccinic acid, 1,2-benzenedithiol, 1,2-benzenedimethanethiol, 1,3-benzenedithiol, 1,3-benzenedimethanethiol, 1,4-benzenedimethanethiol, 3,4-dimercaptotoluene, 4 -Chloro-1,3-benzenedithiol, 2,4,6-trimethyl-1,3-benzenedimethanethiol, -Hexylamino-4,6-dimercapto-1,3,5-triazine, 2-diethylamino-4,6-dimercapto-1,3,5-triazine, 2-cyclohexylamino-4,6-dimercapto-1,3 , 5-triazine, 2-di-n-butylamino-4,6-dimercapto-1,3,5-triazine, ethylene glycol bis (3-mercaptopropionate), butanediol bisthioglycolate, ethylene glycol bis Thioglycolate, 2,5-dimercapto-1,3,4-thiadiazole, 2,2 ′-(ethylenedithio) diethanethiol, 2,2-bis (2-hydroxy-3-mercaptopropoxyphenylpropane) and 1 , 4-bis (3-mercaptobutyryloxy) butane and the like.

  Among the compounds (C), examples of the compound having three thiol groups (c) include 1,2,6-hexanetriol trithioglycolate, 1,3,5-trithiocyanuric acid, trimethylolpropane tris (3 -Mercaptopropionate), trimethylolpropane tristhioglycolate and tris [(3-mercaptopropionyloxy) -ethyl] isocyanurate.

  Among the compounds (C), examples of the compound having four thiol groups (c) include pentaerythritol tetrakis (3-mercaptopropionate) and pentaerythritol tetrakisthioglycolate.

Among the compounds (C), as a compound having 5 or more thiol groups (c), dipentaerythritol hexakis (3-mercaptopropionate) and a (meth) acrylate monomer having a hydroxy group are essential components. Examples include a radical polymer obtained as a monomer and an esterified product of a mercapto organic acid.
The radical polymer containing the (meth) acrylate monomer having a hydroxy group as an essential constituent monomer may be a copolymer with another (meth) acrylate monomer [methyl (meth) acrylate, etc.]. .
The esterified product with the mercapto organic acid may be esterified with another organic acid (p-toluenesulfonic acid or the like) in addition to the mercapto organic acid.

Of the compounds (C), those having two or more thiol groups (c) are preferred from the viewpoint of curability and storage stability, and more preferably those having three or more thiol groups (c). Compounds are particularly preferred, trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate) and pentaerythritol tetrakis (3-mercaptobutyrate).
The said compound (C) may be used individually by 1 type, or may use 2 or more types together.

From the viewpoint of hardness, the weight ratio of the monomer (A) in the curable composition in the first invention is preferably 5 to 92% by weight, more preferably, based on the weight of the curable composition. It is 10 to 92% by weight, particularly preferably 20 to 90% by weight, and most preferably 30 to 70% by weight.
Moreover, the weight ratio of the compound (B1) in the curable composition in the first invention is 1 to 90% by weight based on the weight of the curable composition from the viewpoint of curability and storage stability. It is preferably 1 to 60% by weight, more preferably 10 to 30% by weight.

Next, the second invention will be described.
The compound (B2) having an ethylenically polymerizable group (a), an acidic functional group (b), and a thiol group (c), which are essential components in the second invention, is the compound described in the first invention. (B2) can be used.
In addition, the curable composition in said 2nd invention contains the said monomer (A), a compound (B1), a compound (B '), and a compound (C) besides the said compound (B2). It may be.

  From the viewpoints of hardness and curability, the weight ratio of the compound (B2) in the curable composition in the second invention is preferably 80 to 95% by weight, more preferably 85 to 95% by weight. is there.

The curable composition in the second invention preferably contains the monomer (A) from the viewpoints of hardness and curability.
In the case where the curable composition in the second invention contains the monomer (A), the weight ratio of the compound (B2) is that of the curable composition from the viewpoint of hardness and curability. It is preferable that it is 1 to 60 weight% on the basis of a weight, More preferably, it is 5 to 30 weight%.
Further, the weight ratio of the monomer (A) in the curable composition in the second invention is preferably 30 to 99% by weight based on the weight of the curable composition from the viewpoint of hardness, Preferably it is 40-90 weight%, Most preferably, it is 60-70 weight%.

Next, matters common to the first invention and the second invention (hereinafter sometimes abbreviated as the present invention) will be described.
The acid value of the curable composition of the present invention is preferably 1 to 70 mgKOH / g, more preferably 1 to 50 mgKOH / g, and particularly preferably 1 to 30 mgKOH / g from the viewpoint of storage stability. Most preferably, it is 1-15 mgKOH / g.

The thiol group content of the curable composition of the present invention is preferably 0.1 to 5.0 mmol / g, more preferably 0.1 to 1.0 mmol / g, and particularly preferably 0.1. -0.5 mmol / g.
When it is 0.1 mmol / g or more, the curability is good, and when it is 5.0 mmol / g or less, the storage stability is good.
The thiol group content can be quantified according to the method described in JP-A-62-187731.

  In the curable composition of the present invention, a value obtained by dividing the acid value (mgKOH / g) by the content (mmol / g) of the thiol group [[acid value (mgKOH / g)] / [thiol group] Content (mmol / g)]] is preferably 0.1 to 100, more preferably 10 to 80, and particularly preferably 20 to 50 from the viewpoint of curability.

The curable composition of the present invention preferably further contains a radical polymerization initiator (D) for the purpose of improving curability.
As radical polymerization initiator (D), phosphine oxide compound (D1), benzoylformate compound (D2), thioxanthone compound (D3), oxime ester compound (D4), hydroxybenzoyl compound (D5) Benzophenone compound (D6), ketal compound (D7), α-aminoalkylphenone compound (D8), and the like.

  Examples of the phosphine oxide compound (D1) include bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

  Examples of the benzoylformate compound (D2) include methylbenzoylformate.

  Examples of the thioxanthone compound (D3) include isopropylthioxanthone, 2,4-diethylthioxanthone, and 2-chlorothioxanthone.

  Examples of the oxime ester compound (D4) include 1- [4- (phenylthio) phenyl] -1,2-octanedione 2- (O-benzoyloxime) and ethanone-1- [9-ethyl-6- (2- Methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime) and the like.

  Examples of the hydroxybenzoyl compound (D5) include 2-hydroxy-2-methyl-1-phenylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone.

  Examples of the benzophenone compound (D6) include benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 4,4'-bismethylaminobenzophenone, and the like.

  Examples of the ketal compound (D7) include acetophenone dimethyl ketal and benzyl dimethyl ketal.

  Examples of the α-aminoalkylphenone compound (D8) include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2- (dimethylamino) -2-[(4 -Methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone and the like.

Among these photopolymerization initiators (D), phosphine oxide compounds (D1) and α-aminoalkylphenone compounds (D8) are preferable from the viewpoint of curability and coloring of the cured product.
The photopolymerization initiator (D) may be used alone or in combination of two or more.

  From the viewpoint of curability and transparency, the weight ratio of the radical polymerization initiator (D) in the curable composition of the present invention is preferably 5 to 20% by weight based on the weight of the curable composition, More preferably, it is 5 to 15% by weight.

If necessary, the curable composition of the present invention may contain various additives within a range not impairing the effects of the present invention.
Examples of additives include plasticizers, organic solvents, dispersants, antifoaming agents, thixotropic agents (thickeners), slip improvers, antioxidants, hindered amine light stabilizers and ultraviolet absorbers. .

  The curable composition of the present invention uses, for example, a known mechanical mixing method (for example, a method using a mechanical stirrer or a magnetic stirrer) with the essential components and optional components of each invention in a temperature range of 20 to 80 ° C. Can be manufactured by mixing uniformly.

The curable composition of the present invention is diluted with a solvent (such as methyl ethyl ketone) if necessary, applied to at least a part of at least one side of the substrate, and dried if necessary, and then active energy rays (ultraviolet rays, electron beams and A hard coat coating having a cured film can be obtained by curing by irradiation with X-rays or the like.
In coating, a coating machine [bar coater, gravure coater, roll coater (size press roll coater, gate roll coater, etc.), air knife coater, spin coater, blade coater, etc.] can be used.
The coating film thickness is preferably 0.5 to 300 μm as the film thickness after curing and drying. A more preferable upper limit is 250 μm from the viewpoint of drying properties and curability, and a more preferable lower limit is 1 μm from the viewpoint of hardness.

  As said base material, what was comprised using resin, such as a glass base material and methylmethacrylate (co) polymer, a polyethylene terephthalate, a polycarbonate, a polytriacetylcellulose, a polycycloolefin, etc. are mentioned.

When the curable composition of the present invention is used after being diluted with a solvent, it is preferably dried after coating. Examples of the drying method include hot air drying (such as a dryer).
The drying temperature is preferably 10 to 200 ° C., and a more preferable upper limit is 150 ° C. from the viewpoint of the smoothness and appearance of the coating film, and a further preferable lower limit is 30 ° C. from the viewpoint of the drying speed.

  The active energy rays in the present invention include ultraviolet rays, electron beams, X-rays, infrared rays and visible rays. Of these active energy rays, ultraviolet rays and electron beams are preferable from the viewpoint of curability and suppression of resin deterioration.

When the active energy ray-curable composition of the present invention is cured by ultraviolet rays, an LED light source ultraviolet ray irradiation device [for example, LED light source ultraviolet ray irradiation device “FJ100 150 × 20 365, manufactured by poseon TECHNOLOGY Co., Ltd.”] can be used.
Note that the LED light source has lower power consumption, less generation of ozone, lower running cost, and less environmental burden than other general ultraviolet light sources.
The dose of ultraviolet rays is preferably 50~10,000mJ / cm ² from a flexible viewpoint of curability and cured product of the curable composition, more preferably is 200~5,000mJ / cm ² .
The active energy ray-curable composition of the present invention can be applied to ultraviolet irradiation devices such as a high-pressure mercury lamp, an ultra-high pressure mercury lamp, and a metal halide lamp that emit ultraviolet light having a wide wavelength from an LED light source, and exhibits performance.

  Hereinafter, although an example and a comparative example explain the present invention further, the present invention is not limited to these. Hereinafter, unless otherwise specified, “%” represents “% by weight” and “parts” represents “parts by weight”.

Production Example 1 [Production of Compound (B1-1) Having Thiol Group and Carboxy Group]
In a glass reaction vessel equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen introduction tube, 60 parts of methyl methacrylate, 10 parts of methacrylic acid, 30 parts of 2-hydroxyethyl methacrylate and 200 parts of toluene were charged. After substituting the gas phase part in the system with nitrogen, a solution prepared by dissolving 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) in 50 parts of toluene was added, heated to 90 ° C., and the same. The reaction was carried out at temperature for 4 hours.
After completion of the reaction, a Dean-Stark apparatus and a reflux condenser are attached to a glass reaction vessel containing the reaction product, and 20 parts of β-mercaptopropionic acid and 2 parts of p-toluenesulfonic acid are added and stirred while stirring. The mixture was heated to 0 ° C. and further reacted at the same temperature for 6 hours. After the reaction, the reaction mixture was cooled, neutralized with a 10% aqueous sodium hydrogen carbonate solution, and filtered. After filtration, toluene and water were distilled off under reduced pressure to obtain a compound (B1-1) having a thiol group and a carboxy group. The acid value was 52 mgKOH / g, and the thiol group content was 1.51 mmol / g.

Production Example 2 [Production of Compound (B1-2) Having Thiol Group and Phosphate Group]
In a glass reaction vessel equipped with a heating / cooling / stirring device, a reflux condenser and a nitrogen introduction tube, 60 parts of methyl methacrylate, 10 parts of 2-methacryloyloxyethyl acid phosphate, 30 parts of 2-hydroxyethyl methacrylate and 200 parts of toluene Was charged. After substituting the gas phase part in the system with nitrogen, a solution prepared by dissolving 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) in 50 parts of toluene was added, heated to 90 ° C., and the same. The reaction was carried out at temperature for 4 hours.
After completion of the reaction, a Dean-Stark apparatus and a reflux condenser are attached to a glass reaction vessel containing the reaction product, and 20 parts of β-mercaptopropionic acid and 2 parts of p-toluenesulfonic acid are added and stirred while stirring. The mixture was heated to 0 ° C. and further reacted at the same temperature for 6 hours. After the reaction, the reaction mixture was cooled, neutralized with a 10% aqueous sodium hydrogen carbonate solution, and filtered. After filtration, toluene and water were distilled off under reduced pressure to obtain a compound (B1-2) having a thiol group and a phosphate group. The acid value was 43 mgKOH / g, and the thiol group content was 1.51 mmol / g.

Production Example 3 [Production of Compound (B2-1) Having Thiol Group, Carboxy Group, and Ethylene Polymerizable Group]
A glass reaction vessel equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen introduction tube was charged with 50 parts of methyl methacrylate, 10 parts of methacrylic acid, 30 parts of 2-hydroxyethyl methacrylate and 200 parts of toluene. After substituting the gas phase part in the system with nitrogen, a solution prepared by dissolving 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) in 50 parts of toluene was added, heated to 90 ° C., and the same. The reaction was carried out at temperature for 4 hours. After completion of the reaction, the mixture was cooled, charged with 20 parts of 2-acryloyloxyethyl isocyanate and 0.5 part of a 50% 2-ethylhexanoic acid solution of bismuth tri (2-ethylhexanoate) as a catalyst, and heated to 80 ° C. Furthermore, it was made to react at the same temperature for 4 hours.
After completion of the reaction, a Dean-Stark apparatus and a reflux condenser were attached to a glass reaction vessel containing the reaction product, and 15 parts of β-mercaptopropionic acid and 2 parts of p-toluenesulfonic acid were added and stirred while stirring. The mixture was heated to 0 ° C. and further reacted at the same temperature for 6 hours. After the reaction, the reaction mixture was cooled, neutralized with a 10% aqueous sodium hydrogen carbonate solution, and filtered. After filtration, toluene and water were distilled off under reduced pressure to obtain a compound (B2-1) having a thiol group, a carboxy group, and an acryloyl group. The acid value was 50 mgKOH / g, and the thiol group content was 1.08 mmol / g.

Comparative Production Example 1 [Production of methyl methacrylate / methacrylic acid copolymer (B′1-1)]
70 parts of methyl methacrylate, 30 parts of methacrylic acid and 200 parts of toluene were charged into a glass reaction vessel equipped with a heating / cooling / stirring device, a reflux condenser, and a nitrogen introduction tube. After substituting the gas phase part in the system with nitrogen, a solution prepared by dissolving 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) in 50 parts of toluene was added, heated to 90 ° C., and the same. The reaction was carried out at temperature for 4 hours. After completion of the reaction, toluene was distilled off under reduced pressure to obtain a methyl methacrylate / methacrylic acid copolymer (B′1-1) as a compound having a carboxy group. The acid value was 186 mgKOH / g.

Examples 1-9 and Comparative Examples 1-6
It mixed uniformly by the compounding composition (weight part) shown in Table 1, and obtained the curable composition of Examples 1-9 and the comparative curable composition of Comparative Examples 1-6.

The raw materials used in Table 1 are as follows.
(A-1): Acryloylmorpholine [trade name: ACMO, manufactured by KJ Chemicals Co., Ltd.]
(A-2): Isobornyl acrylate [trade name: IBXA, manufactured by Osaka Organic Chemical Industry Co., Ltd.]
(A-3): 1,6-hexanediol diacrylate [trade name: Biscote # 230, manufactured by Osaka Organic Chemical Industry Co., Ltd.]
(A-4): Pentaerythritol tetraacrylate [trade name: Neomer EA-300, manufactured by Sanyo Chemical Industries, Ltd.]
(A-5): N-vinylcaprolactam [manufactured by BASF]
(B′2-1): 2-acryloyloxyethyl-phthalic acid [trade name: HOA-MPL (N), manufactured by Kyoeisha Chemical Co., Ltd., a compound having a carboxy group, acid value 226 mgKOH / g]
(C-1): 1,4-bis (3-mercaptobutyryloxy) butane [trade name: Karenz MT BD1, manufactured by Showa Denko KK, 2 thiol groups, thiol group content 6.68 mmol / g]
(C-2): Pentaerythritol tetrakis (3-mercaptobutyrate) [trade name: Karenz MT PE1, manufactured by Showa Denko KK, 4 thiol groups, thiol group content 7.34 mmol / g]
(C-3): pentaerythritol tetrakis (3-mercaptopropionate) [trade name: PEMP, manufactured by SC Organic Chemical Co., Ltd., 4 thiol groups, thiol group content: 8.19 mmol / g]
(D-1): 2,4,6-trimethylbenzoyldiphenylphosphine oxide [trade name: Irgacure TPO, manufactured by BASF Corp., acylphosphine oxide polymerization initiator]
(D-2): Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide [trade name: Irgacure 819, manufactured by BASF, acylphosphine oxide polymerization initiator]
(D-3): 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone [trade name: Irgacure 379, BASF Corporation Manufactured by alkylphenone radical polymerization initiator]
Additive: Alkylene oxide modified polydimethylsiloxane [trade name “BYK-302”, manufactured by Big Chemie Japan Co., Ltd .; slip improver]

  About the curable composition obtained in Examples 1-9 and the curable composition for comparison obtained in Comparative Examples 1-6, the curability, pencil hardness, the total light transmittance of the cured product, the adhesion of the cured product, and The storage stability was evaluated.

<Evaluation of curability>
Each curable composition was applied to a glass substrate [Corning Eagle XG (thickness 0.7 mm)] with a spin coater so that the film thickness after curing was 20 μm, and an LED light source ultraviolet irradiation device [model number: FJ100 150 × 20 365, manufactured by Phoseon TECHNOLOGY Co., Ltd., irradiation wavelength 365 nm], ultraviolet rays were irradiated for 5 seconds at an irradiation intensity of 400 mW / cm ² , and an exposure amount of 2,000 mJ / cm ² was applied to cure the curable composition. I let you.

The surface of the cured product was touched with a finger to check for stickiness, and evaluated according to the following criteria.
○: No stickiness at all ×: Stickiness remains

<Evaluation of pencil hardness>
The pencil hardness was measured for the cured product obtained by the above evaluation of curability according to JIS K-5400. In addition, when using it for a hard coat use, it is necessary for pencil hardness to be 2H or more.

<Evaluation of total light transmittance>
In accordance with JIS-K7105, the cured product obtained by the above-described evaluation of curability is used for total light transmittance using a total light transmittance measuring device [trade name “haze-garddual”, manufactured by BYK Gardner Co., Ltd.]. (%) Was measured.
When the sample is prepared under these sample preparation conditions and used for general hard coat applications, the total light transmittance needs to be 88% or more.

<Evaluation of adhesion>
This was performed according to JIS K5600-5-6.
The cured product obtained by the above evaluation of curability is allowed to stand for 24 hours in an environment of 23 ° C. and a relative humidity of 50%, and then cut into a 1 mm width with a cutter knife and a grid pattern (5 × 5) It was created.
A cellophane adhesive tape was affixed on the grid, peeled 90 degrees, and the peeled state of the cured product from the glass substrate was visually observed. The number of squares in close contact without peeling in 25 squares was counted and evaluated.
Further, in the above evaluation of adhesion, instead of leaving for 24 hours in an environment of 23 ° C. and a relative humidity of 50%, it was left for 24 hours in an environment of 60 ° C. and a relative humidity of 90%. The evaluation was performed in the same manner as the above-described evaluation of adhesion, and the evaluation of adhesion under more severe conditions was also performed.

<Evaluation of storage stability>
Each curable composition is stored in a 40 ° C environment, taken out after 30 days, the viscosity is measured, and the rate of change from the initial viscosity (viscosity before starting storage in a 40 ° C environment) is calculated. Then, the following criteria were used for evaluation.
The viscosity was measured with an E-type viscometer [trade name: TVE-35, manufactured by Toki Sangyo Co., Ltd.].
Rate of change (%) = (viscosity after 30 days−initial viscosity) / initial viscosity × 100
○: Less than 10% ×: 10% or more

As shown in Table 1, the curable compositions of Examples 1 to 9 of the present invention are excellent in all points of curability by LED light source, pencil hardness, total light transmittance, adhesion, and storage stability.
On the other hand, the curable composition of Comparative Example 1 that does not contain any compound having a thiol group (c) has insufficient curability, pencil hardness, and adhesion.
Further, the comparative curable composition of Comparative Example 2 that does not contain any compound having an acidic functional group (b) has insufficient adhesion and storage stability.
Further, Comparative Example 3 containing neither of the above (B1) and (B2), the compound (B ′) having the acidic functional group (b) and having no thiol group (c). The comparative curable compositions of -6 are insufficient in adhesion and storage stability.

  Since the curable composition of the present invention has high storage stability and is excellent in adhesion to a substrate, curability and hardness, it can be suitably used as a hard coat film.

Claims (7)

A monomer (A) having an ethylenically polymerizable group (a) and having neither an acidic functional group (b) nor a thiol group (c), an acidic functional group (b) and a thiol group (c) And a compound (B2) containing the compound (B1) having no ethylenically polymerizable group (a) or having an ethylenically polymerizable group (a), an acidic functional group (b) and a thiol group (c). A curable composition containing   The curable composition according to claim 1, wherein the acidic functional group (b) is at least one group selected from the group consisting of a carboxy group, a phosphoric acid group, and a sulfo group.   The curable composition according to claim 1 or 2, wherein the thiol group content is 0.1 to 5.0 mmol / g.   The curable composition according to any one of claims 1 to 3, wherein the acid value is 1 to 70 mgKOH / g.   Furthermore, the curable composition of any one of Claims 1-4 containing a radical polymerization initiator (D).   The curable composition according to any one of claims 1 to 5, wherein the ethylenically polymerizable group (a) is a (meth) acryloyl group. The cured film formed by hardening the curable composition of any one of Claims 1-6.