JP2015110762A - Active ray-curable adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active ray-curable adhesive composition which has good storage stability at room temperature and good curability and whose cured product is excellent in adhesion (particularly, heat-resistant adhesion and moisture-resistant adhesion) to various substrates.SOLUTION: The active ray-curable adhesive composition contains a photoacid generator (A) and a cationically polymerizable substance (B) comprising a monofunctional cationically polymerizable substance (B1) and a polyfunctional cationically polymerizable substance (B2). The photoacid generator (A) is a sulfonium salt derivative (A1) or an iodonium salt derivative (A2), and its anion is a hexafluorophosphate anion, a trifluoro[tris(perfluoroethyl)]phosphate anion, or a tetrakis(perfluorophenyl)borate anion. The weight ratio of (B2)/(B1) is 0.01-1.

Description

  The present invention is cured by irradiation with actinic rays, and actinic ray curable adhesive compositions and actinic ray curable adhesive compositions useful for flat panel displays, touch panels, or electronic component manufacturing are cured. It relates to a cured product.

  At present, flat panel displays (FPDs) represented by liquid crystal displays and organic EL displays are indispensable for many electronic devices such as televisions, tablet terminals, and mobile phones represented by smartphones, and constitute FPDs. The demand for many optical materials is also growing significantly. In addition, most smartphones and tablet terminals are equipped with touch panels in most models, and materials used in electronic devices include light resistance, weather resistance, heat resistance, moisture resistance, and other reliability, adhesion, and adhesion. There are various requirements such as properties and transparency, and there is a demand for a highly reliable resin especially during heat and humidity resistance tests.

  In recent years, cover glasses used for flat panels have become thinner. When the cover glass is thin, when the cover glass and the LCD are bonded to each other using a resin that is cured by actinic ray irradiation as an adhesive, the LCD is likely to bend and deform due to stress generated during the curing. A conventional actinic ray curable composition (see, for example, Patent Document 1) has insufficient curability, and thus unevenness in brightness occurs when an LCD is turned on, and an adhesive surface peels off during a heat and moisture resistance test. There is a problem that this problem occurs.

  Therefore, development of an actinic ray curable adhesive composition having good curability and high adhesive strength of the cured product is strongly demanded.

  Patent Document 2 discloses an epoxy resin composition containing an epoxy compound and an amine curing agent. It is described that the epoxy resin composition is suitably used for applications such as adhesion of electronic parts. However, a composition comprising a cationically polymerizable substance such as an epoxy compound and a latent thermosetting agent such as an amine-based curing agent has a long curing time but poor storage stability at room temperature and poor handling properties.

  Therefore, development of an actinic ray curable adhesive composition having high storage stability at room temperature is strongly demanded.

JP 2013-020258 A JP-A-2005-187609

  The present invention has been made in view of the above problems, and the object of the present invention is to have high storage stability at room temperature, good curability, and adhesive strength of a cured product (particularly heat-resistant adhesive and moisture-resistant adhesive). It is to provide an actinic ray curable adhesive composition having a high property.

As a result of intensive studies to achieve the above object, the present inventors have reached the present invention.
That is, the present invention relates to actinic ray curing containing a photoacid generator (A) and a cationic polymerizable substance (B) comprising a monofunctional cationic polymerizable substance (B1) and a polyfunctional cationic polymerizable substance (B2). Type adhesive composition, photoacid generator (A) is sulfonium salt derivative (A1) or iodonium salt derivative (A2), and its anion is hexafluorophosphate anion, trifluoro [tris (perfluoroethyl)] An actinic ray curable adhesive composition which is a phosphate anion or a tetrakis (perfluorophenyl) borate anion and has a weight ratio of (B2) / (B1) of 0.01 to 1; It is a cured product obtained by curing a curable adhesive composition by irradiation with actinic rays.

  By using the actinic ray curable adhesive composition of the present invention, the storage stability at room temperature is high, so there is little change in viscosity, the curability is good, and the adhesive strength of the cured product (especially heat resistant adhesiveness, moisture resistant adhesiveness). A cured product having a high property) can be produced.

  Hereinafter, the photoacid generator (A) and the cationic polymerizable substance (B), which are essential components of the actinic ray curable adhesive composition of the present invention, will be described in order.

In the present invention, the photoacid generator (A) is a compound that generates an acid by active light, and is a sulfonium salt derivative (A1) or an iodonium salt derivative (A2). The anion is a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion.
(A) may be used independently and may use 2 or more types together.

  Examples of the sulfonium salt derivative (A1) in the present invention include compounds represented by the following general formula (1) or the following general formula (2).

In the general formula (1) or (2), A ¹ is a divalent or trivalent group represented by the following general formulas (3) to (10) or a sulfide group.
Ar ^{1 to} Ar ⁷ in the general formula (1) or (2) each independently have at least one benzene ring skeleton, a halogen atom, an acyl group having 1 to 20 carbon atoms, and an alkyl having 1 to 20 carbon atoms. Group, an alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, a nitro group, a carboxyl group, a hydroxyl group, a mercapto group, an amino group, a cyano group, a phenyl group, An aromatic hydrocarbon group or a heterocyclic group optionally substituted with at least one atom selected from the group consisting of a naphthyl group, a phenoxy group, a phenylthio group, and a biphenylthio group, or a substituent thereof, Ar ^{1 to} Ar ⁴ , Ar ⁶ and Ar ⁷ are monovalent groups, and Ar ⁵ is a divalent group.
(X ¹ ) in the general formula (1) or (2) represents a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion.
a is an integer of 0 to 2, b is an integer from 1 to 3, and a + b is an integer equal the valence of ^{A 1} in 2 or 3.

R ^{1 to} R ⁷ in the general formulas (5) to (8) are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a halogen atom, an acyl group having 1 to 20 carbon atoms, or 1 to carbon atoms. 20 represents an aromatic hydrocarbon group which may be substituted with at least one atom or substituent selected from the group consisting of 20 alkyl groups, amino groups, cyano groups, phenyl groups, naphthyl groups, phenoxy groups and phenylthio groups. , R ¹ and R ² , R ⁴ and R ⁵ , and R ⁶ and R ⁷ may be bonded to each other to form a ring structure.

As A ¹ in the general formula (2), the groups represented by the general formulas (5) and (7) to (10) and the sulfide group are preferable from the viewpoint of acid generation efficiency, and the general formula (5), The groups represented by (8) to (10) and sulfide groups are more preferable.

In Ar ^{1 to} Ar ⁷ in the general formula (1) and the general formula (2), the sulfonium salt derivative (A1) represented by the general formula (1) or the general formula (2) has absorption in the ultraviolet to visible light region. It is a group that becomes.
The number of benzene ring skeletons in Ar ^{1 to} Ar ⁷ is preferably 1 to 5, and more preferably 1 to 4.
As an example in the case of having one benzene ring skeleton, a residue obtained by removing one or two hydrogen atoms from benzene or a heterocyclic compound such as benzofuran, benzothiophene, indole, quinoline, coumarin, and the like can be given.
Examples of the case of having two benzene ring skeletons include one or two hydrogen atoms from heterocyclic compounds such as naphthalene, biphenyl, fluorene, or dibenzofuran, dibenzothiophene, xanthone, xanthene, thioxanthone, acridine, phenothiazine, and thianthrene. Residues excluded are listed.
As an example in the case of having three benzene ring skeletons, for example, one or two hydrogen atoms are removed from a heterocyclic compound such as anthracene, phenanthrene, terphenyl, p- (thioxanthyl mercapto) benzene, and naphthobenzothiophene. Residue.
As an example in the case of having four benzene ring skeletons, for example, a residue obtained by removing one or two hydrogen atoms from naphthacene, pyrene, benzoanthracene, triphenylene and the like can be mentioned.

  Examples of the halogen atom include fluorine, chlorine, bromine and iodine, and fluorine and chlorine are preferable.

  Examples of the acyl group having 1 to 20 carbon atoms include formyl group, acetyl group, propionyl group, isobutyryl group, valeryl group, and cyclohexylcarbonyl group.

  Examples of the alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, n- or iso-propyl group, n-, sec- or tert-butyl group, n-, iso- or neo-pentyl group, hexyl group, A heptyl group, an octyl group, etc. are mentioned.

  Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, n- or iso-propoxy group, n-, sec- or tert-butoxy group, n-, iso- or neo-pentyloxy group, A hexyloxy group, a heptyloxy group, an octyloxy group, etc. are mentioned.

  Examples of the alkylthio group having 1 to 20 carbon atoms include a methylthio group, an ethylthio group, an n- or iso-propylthio group, an n-, sec- or tert-butylthio group, an n-, iso- or neo-pentylthio group, and a hexylthio group. , Heptylthio group, octylthio group and the like.

  Examples of the alkylsilyl group having 1 to 20 carbon atoms include trialkylsilyl groups such as trimethylsilyl group and triisopropylsilyl group. Here, the alkyl may be a linear structure or a branched structure.

As the atoms or substituents substituted by Ar ^{1 to} Ar ⁷ , preferred from the viewpoint of acid generation efficiency are halogen atoms, cyano groups, phenyl groups, naphthyl groups, phenoxy groups, phenylthio groups, alkyl groups having 1 to 20 carbon atoms. , An alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, and an acyl group having 1 to 20 carbon atoms.
More preferable are a cyano group, a phenyl group, an alkyl group having 1 to 15 carbon atoms, an alkoxy group having 1 to 15 carbon atoms, an alkylthio group having 1 to 15 carbon atoms, and an acyl group having 1 to 15 carbon atoms, and particularly preferable. Are an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, and an acyl group having 1 to 10 carbon atoms.
The above alkyl moiety may be linear, branched or cyclic.

Ar ^{1 to} Ar ⁴ , Ar ⁶ and Ar ⁷ are preferably a phenyl group, a p-methylphenyl group, a p-methoxyphenyl group, a p-tert-butylphenyl group, 2, 4, from the viewpoint of acid generation efficiency. 6-trimethylphenyl group, p- (thioxanthylmercapto) phenyl group and m-chlorophenyl group.

Ar ⁵ is preferably a phenylene group, a 2- or 3-methylphenylene group, a 2- or 3-methoxyphenylene group, a 2- or 3-butylphenylene group, and 2- or 3-chloro, from the viewpoint of acid generation efficiency. A phenylene group.

In the general formula (1) or (2), the anion represented by (X ¹ ) ⁻ is a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion. Yes, preferably a trifluoro [tris (perfluoroethyl)] phosphate anion and a tetrakis (perfluorophenyl) borate anion. From the viewpoint of reaction rate, it is necessary to use these anions.

  As the sulfonium salt derivative (A1) of the present invention, compounds having a triphenylsulfonium cation or a tri-p-tolylsulfonium cation as a cation skeleton and the following general formulas (11) to (14) are preferable from the viewpoint of acid generation efficiency. And more preferred are compounds represented by the following general formulas (11) and (12).

(X ¹ ) ⁻ in the general formulas (11) to (14) represents a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion.

  Examples of the iodonium salt derivative (A2) in the present invention include compounds represented by the following general formula (15) or the following general formula (16).

In the formula, A ² is a divalent or trivalent group represented by any one of the general formulas (3) to (10), or a sulfide group.
Ar ^{8 to} Ar ¹² each independently have at least one benzene ring skeleton, a halogen atom, an acyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, carbon Number 1-20 alkylthio group, carbon number 1-20 alkylsilyl group, nitro group, carboxyl group, hydroxyl group, mercapto group, amino group, cyano group, phenyl group, naphthyl group, phenoxy group, phenylthio group and biphenylthio group An aromatic hydrocarbon group or a heterocyclic group which may be substituted with at least one substituent selected from the group consisting of: Ar ^{8 to} Ar ¹⁰ and Ar ¹² are monovalent groups; Ar ¹¹ is 2 Is a valent group.
(X ¹ ) ⁻ represents a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion. c is an integer of 0 to 2, d is an integer from 1 to 3, and c + d is an integer equal the valence of ^{A 2} in 2 or 3.

  As a halogen atom, an acyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, and an alkylsilyl group having 1 to 20 carbon atoms The thing similar to what was described by description of General formula (1) and General formula (2) is illustrated.

As A ² in the general formula (16), a group represented by the general formula (5) and the general formulas (7) to (10) is preferable from the viewpoint of the efficiency of generating an acid. And groups represented by (8) to (10) are more preferable.

Ar ^{8 to} Ar ¹² in the general formula (15) or the general formula (16) are groups in which the compound represented by the general formula (15) or the general formula (16) has absorption in the ultraviolet to visible light region. is there.
The number of benzene ring skeletons in Ar ^{8 to} Ar ¹² is preferably 1 to 5, and more preferably 1 to 4. Specific examples of Ar ^{8 to} Ar ¹² include general formula (1) or general formula (2). The thing similar to what was illustrated as Ar < ¹ > -Ar < ⁷ > of these is mentioned, A preferable thing is also the same.

(X ¹ ) ⁻ represents a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion.

  As the iodonium salt derivative (A2), from the viewpoint of acid generation efficiency, (4-methylphenyl) {4- (2-methylpropyl) phenyl} iodonium cation, [bis (4-t-butylphenyl)] iodonium are preferable. Compounds having a cation and a [bis (4-methoxyphenyl)] iodonium cation as a cation skeleton, and other compounds represented by the following general formulas (17) to (20), more preferably the following general formula (17 ) To (19).

In the general formulas (17) to (20), R ⁸ and R ⁹ are a hydrogen atom, a halogen atom, an acyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, C1-C20 alkylthio group, C1-C20 alkylsilyl group, nitro group, carboxyl group, hydroxyl group, mercapto group, amino group, cyano group, phenyl group, naphthyl group, phenylthio group and biphenylthio group An atom or substituent selected from the group.
Moreover, about R < ¹⁰ > -R < ¹³ >, a phenyl group, a naphthyl group, a C1-C20 alkyl group, and a C1-C20 acyl group are represented.
(X ¹ ) ⁻ represents a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (perfluorophenyl) borate anion.

  As a halogen atom, an acyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, and an alkylsilyl group having 1 to 20 carbon atoms The thing similar to what was described by description of General formula (1) and General formula (2) is illustrated.

R ⁸ and R ⁹ are preferably a halogen atom, a cyano group, a phenyl group, a naphthyl group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and an acyl group having 1 to 20 carbon atoms. More preferred are a cyano group, a phenyl group, an alkyl group having 1 to 15 carbon atoms, an alkoxy group having 1 to 15 carbon atoms and an acyl group having 1 to 15 carbon atoms, and particularly preferred are those having 1 to 10 carbon atoms. An alkyl group, an alkoxy group having 1 to 10 carbon atoms, and an acyl group having 1 to 10 carbon atoms. The above alkyl moiety may be linear, branched or cyclic.
R ^{10 to} R ¹³ are preferably a phenyl group, an alkyl group having 1 to 20 carbon atoms, and an acyl group having 1 to 20 carbon atoms, and more preferably an alkyl group having 1 to 15 carbon atoms and 1 carbon atom. ˜15 acyl groups, particularly preferred are alkyl groups having 1 to 10 carbon atoms and acyl groups having 1 to 10 carbon atoms. The above alkyl moiety may be linear, branched or cyclic.

  In general, a photopolymerization initiator that can be used for curing in the visible light region (360 nm to 830 nm; see JIS-Z8120) is colored by the initiator itself because it absorbs visible light, which adversely affects the hue of the cured film. However, by using the compound represented by the general formula (2) or the general formula (16), adverse effects on the hue of the cured film can be suppressed.

  The content of the photoacid generator (A) in the actinic ray curable adhesive composition of the present invention is 0.05 to 30% by weight with respect to the weight of the cationic polymerizable substance (B) from the viewpoint of photocurability. %, Preferably 0.1 to 25% by weight.

As the cationic polymerizable substance (B) in the present invention, a monofunctional cationic polymerizable substance (B1) and a polyfunctional cationic polymerizable substance (B2) are used in combination.
If the monofunctional cationic polymerizable substance (B1) is not contained, the storage stability is lowered and the adhesive strength of the cured product is lowered. Moreover, if it does not contain a polyfunctional cation polymerizable substance (B2), the heat-resistant adhesiveness and moisture-resistant adhesiveness of hardened | cured material will fall.
From the viewpoint of heat-resistant adhesion, the weight ratio [(B2) / (B1)] of the polyfunctional cation polymerizable substance (B2) and the monofunctional cation polymerizable substance (B1) is 0.01-1. Preferably it is 0.02-0.5, More preferably, it is 0.02-0.1.
The “monofunctional cationic polymerizable substance (B1)” means a cationic polymerizable substance having one cationic polymerizable functional group.
The “polyfunctional cationically polymerizable substance (B2)” means a cationically polymerizable substance having two or more cationically polymerizable functional groups, and contains two or more of the same kind of cationically polymerizable functional groups. Alternatively, a total of two or more different types of cationically polymerizable functional groups may be contained.
Hereinafter, the same description method is used.

  Examples of the monofunctional cationic polymerizable substance (B1) include a monofunctional vinyl ether (B11) having 3 to 40 carbon atoms, a monofunctional epoxy compound (B12) having 3 to 40 carbon atoms, and a monofunctional oxetane compound having 4 to 40 carbon atoms. (B13).

  Examples of the monofunctional vinyl ether (B11) having 3 to 40 carbon atoms include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, n-butyl vinyl ether, t-butyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, stearyl. Vinyl ether, cyclohexyl vinyl ether, cyclohexyl methyl vinyl ether, 4-methylcyclohexyl methyl vinyl ether, benzyl vinyl ether, dicyclopentenyl vinyl ether, 2-dicyclopentenoxyethyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, butoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether , Ethoxyethoxyethyl vinyl Ether, methoxypolyethylene glycol vinyl ether, tetrahydrofurfuryl vinyl ether, 2-hydroxyethyl vinyl ether, 2-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 4-hydroxymethylcyclohexyl methyl vinyl ether, diethylene glycol monovinyl ether, polyethylene glycol vinyl ether, chloroethyl vinyl ether, Examples include chlorobutyl vinyl ether, chloroethoxyethyl vinyl ether, phenylethyl vinyl ether, and phenoxypolyethylene glycol vinyl ether.

  Examples of the monofunctional epoxy compound (B12) having 3 to 40 carbon atoms include phenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, and 1,2-butylene. Oxide, 1,3-butadiene monooxide, 1,2-epoxydodecane, epichlorohydrin, 1,2-epoxydecane, styrene oxide, cyclohexene oxide, 3-methacryloyloxymethylcyclohexene oxide, 3-acryloyloxymethylcyclohexene oxide And 3-vinylcyclohexene oxide.

  Examples of the monofunctional oxetane compound (B13) having 4 to 40 carbon atoms include 3-ethyl-3-hydroxymethyloxetane, 3- (meth) allyloxymethyl-3-ethyloxetane, and (3-ethyl-3-oxetanyl). Methoxy) methylbenzene, 4-fluoro- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, 4-methoxy- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, [1- (3-Ethyl-3-oxetanylmethoxy) ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyloxyethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyl (3 -Ethyl-3-oxetanylmethyl) ether, 2-ethylhexyl ( -Ethyl-3-oxetanylmethyl) ether, ethyldiethylene glycol (3-ethyl-3-oxetanylmethyl) ether, dicyclopentadiene (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyloxyethyl (3-ethyl-3 -Oxetanylmethyl) ether, dicyclopentenyl (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, tetrabromophenyl (3-ethyl-3-oxetanylmethyl) ether 2-tetrabromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, tribromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tribromophenoxyethyl (3-ethyl-3-oxy) Cetanylmethyl) ether, 2-hydroxyethyl (3-ethyl-3-oxetanylmethyl) ether, 2-hydroxypropyl (3-ethyl-3-oxetanylmethyl) ether, butoxyethyl (3-ethyl-3-oxetanylmethyl) ether, Examples include pentachlorophenyl (3-ethyl-3-oxetanylmethyl) ether, pentabromophenyl (3-ethyl-3-oxetanylmethyl) ether, and bornyl (3-ethyl-3-oxetanylmethyl) ether.

  The monofunctional cation polymerizable substance (B1) preferably has a molecular weight of 150 to 1,000, more preferably 150 to 400, from the viewpoint of heat-resistant adhesion.

  As the polyfunctional cationic polymerizable substance (B2), 2 to 8 functional groups are preferable. For example, a polyfunctional vinyl ether (B21), polyfunctional epoxy compound (B22), and polyfunctional oxetane compound (B23) of a divalent to hexavalent alcohol. ), And a compound containing a total of two or more of the functional groups of vinyl group, epoxy group and oxetanyl group.

  Examples of the polyfunctional vinyl ether (B21) of a divalent to hexavalent alcohol include ethylene glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butylene glycol divinyl ether, hexanediol divinyl ether, and alkylene oxide modified. Bisphenol A divinyl ether, alkylene oxide modified bisphenol F divinyl ether, trimethylol ethane trivinyl ether, trimethylol propane trivinyl ether, glycerin trivinyl ether EO-added trimethylol propane trivinyl ether, PO-added trimethylol propane trivinyl ether, ditrimethylol propane tetravinyl ether, Bae Taerythritol tetravinyl ether, EO-added ditrimethylolpropane tetravinyl ether, PO-added ditrimethylolpropane tetravinyl ether, EO-added pentaerythritol tetravinyl ether, PO-added pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether, EO-added di Examples thereof include pentaerythritol hexavinyl ether and PO-added dipentaerythritol hexavinyl ether.

  Examples of the polyfunctional epoxy compound (B22) include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, brominated bisphenol A diglycidyl ether, brominated bisphenol F diglycidyl ether, and brominated bisphenol S. Diglycidyl ether, epoxy novolac resin, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxy Hexylmethyl) adipate, vinylcyclohexene oxide, 4-vinylepoxycyclohexane, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 3,4-epoxy-6-methylcyclohexyl-3 ', 4'-epoxy- 6'-methylcyclohexanecarboxylate, methylenebis (3,4-epoxycyclohexane), dicyclopentadiene diepoxide, ethylene glycol di (3,4-epoxycyclohexylmethyl) ether, ethylenebis (3,4-epoxycyclohexanecarboxylate) , Epoxyhexahydrophthalate dioctyl, epoxyhexahydrophthalate di-2-ethylhexyl, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ester Tellurium, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ethers, 1,1,3-tetradecadiene dioxide, limonene dioxide, 1,2,7,8 -Diepoxyoctane, 1,2,5,6-diepoxycyclooctane and the like.

  Examples of the polyfunctional oxetane compound (B23) include 3,7-bis (3-oxetanyl) -5-oxa-nonane, 3,3 ′-(1,3- (2-methylenyl) propanediylbis (oxymethylene). )) Bis- (3-ethyloxetane), 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, 1,2-bis [(3-ethyl-3-oxetanylmethoxy) methyl] ethane 1,3-bis [(3-ethyl-3-oxetanylmethoxy) methyl] propane, ethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenylbis (3-ethyl-3-oxetanylmethyl) Ether, triethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, tetraethylene glycol vinyl (3-ethyl-3-oxetanylmethyl) ether, tricyclodecanediyldimethylene (3-ethyl-3-oxetanylmethyl) ether, trimethylolpropane tris (3-ethyl-3-oxetanylmethyl) ether, 1,4- Bis (3-ethyl-3-oxetanylmethoxy) butane, 1,6-bis (3-ethyl-3-oxetanylmethoxy) hexane, pentaerythritol tris (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis (3 -Ethyl-3-oxetanylmethyl) ether, polyethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol hexakis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol pentakis 3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipentaerythritol hexakis (3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipenta Erythritol pentakis (3-ethyl-3-oxetanylmethyl) ether, ditrimethylolpropanetetrakis (3-ethyl-3-oxetanylmethyl) ether, EO-modified bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, PO-modified Bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, EO-modified hydrogenated bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, PO-modified hydrogenated bisphenol A bi S (3-ethyl-3-oxetanylmethyl) ether, EO-modified bisphenol F (3-ethyl-3-oxetanylmethyl) ether, and the like.

Examples of the compound containing two or more of the functional groups of vinyl group, epoxy group and oxetanyl group in total include 1-glycidylmethyl-4-vinyloxymethylcyclohexane, 3-ethyl-3-oxetanylmethyl vinyl ether, And 3,3-divinyloxymethyl oxetane and the like.

The actinic ray curable adhesive composition of the present invention is cured by irradiation with actinic rays to obtain a cured product.
Examples of the actinic rays used for curing the actinic ray curable adhesive composition of the present invention include visible rays and ultraviolet rays.
Since the actinic ray curable adhesive composition of the present invention can be photocured by irradiation with an actinic ray of 360 nm to 830 nm, in addition to a commonly used high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, and a high power metal halide lamp (Latest trends in UV / EB curing technology, edited by Radtech Research Association, CM Publishing, page 138, 2006) can be used. Moreover, the irradiation apparatus using an LED light source can also be used conveniently. Furthermore, sunlight, a low-pressure mercury lamp, a semiconductor laser, etc. can be used. Heating may be performed for the purpose of diffusing the acid generated from the photoacid generator (A) and accelerating curing during irradiation with actinic rays and / or after irradiation. The heating temperature is preferably 30 ° C to 200 ° C, more preferably 35 ° C to 150 ° C, and particularly preferably 40 ° C to 120 ° C.

The storage elastic modulus at 25 ° C. after curing of the actinic ray curable adhesive composition of the present invention is preferably 1 × 10 ³ to 1 × 10 ⁶ Pa, more preferably 1 × 10 ³ from the viewpoint of heat-resistant adhesion. ˜1 × 10 ⁵ Pa.
The storage elastic modulus at 25 ° C. is a value obtained by measuring the storage elastic modulus (Pa) (25 ° C.) at a measurement frequency of 10 Hz using a viscoelasticity measuring device such as UBM Co., Ltd. “Rheogel-E4000”.

  The actinic ray curable adhesive composition of the present invention is a coloring material (pigments such as inorganic pigments and organic pigments, dyes), metal oxides, and metal powders from the viewpoint of transparency of the resulting cured product. It is preferable that none of these are substantially contained. Here, the phrase “not substantially contained” means that the content in the actinic ray curable adhesive composition is less than 1% by weight.

  The actinic ray curable adhesive composition of the present invention can contain a sensitizer if necessary.

  Examples of the sensitizer include ketocoumarin, fluorene, thioxanthone, anthraquinone, naphthiazoline, biacetyl, benzyl and derivatives thereof, perylene, and substituted anthracene. The content of the sensitizer is preferably 0 to 20% by weight, more preferably 1 to 15% by weight, and particularly preferably 2 to 10% by weight with respect to the actinic ray curable adhesive composition.

  The actinic ray curable adhesive composition of the present invention further has an adhesion-imparting agent (such as a silane coupling agent), a tackifier, a dispersant, an antifoaming agent, a leveling agent, and thixotropy according to the purpose of use. An imparting agent, slip agent, flame retardant, antistatic agent, antioxidant, ultraviolet absorber and the like can be contained.

  The actinic ray curable adhesive composition of the present invention comprises a photoacid generator (A), a cationic polymerizable substance (B) and, if necessary, a sensitizer, other components and the like, a rotation / revolution stirrer, a ball mill or 3 It can be obtained by kneading with a roll mill or the like. The kneading temperature is preferably 10 ° C to 40 ° C, more preferably 20 ° C to 30 ° C.

  As an application method to the substrate of the actinic ray curable adhesive composition of the present invention, known coating methods such as spin coating, roll coating and spray coating, nanoimprint process, lithographic printing, carton printing, metal printing, offset printing Printing methods such as screen printing and gravure printing can be applied. Further, the present invention can also be applied to coating using an ink jet method or a liquid fixed quantity discharge device that discharges fine droplets continuously.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these. Hereinafter, unless otherwise specified, “%” means “% by weight” and “part” means “part by weight”.

[Production of photoacid generator (A)]
Production Example 1
[Sulphonium Salt Derivative (A1-1) {Compound Represented by Chemical Formula (21)} that Generates Acid by Active Light]

(1) Synthesis of 2- (phenylthio) thioxanthone [intermediate (A1-1-1)]:
11.0 parts of 2-chlorothioxanthone, 4.9 parts of thiophenol, 2.5 parts of potassium hydroxide and 162 parts of N, N-dimethylformamide were uniformly mixed and reacted at 130 ° C. for 9 hours. The product was cooled to room temperature (about 25 ° C.) and poured into 200 parts of distilled water to precipitate the product. This was filtered, and the residue was washed with water until the pH of the filtrate became neutral, and then the residue was dried under reduced pressure to obtain a yellow powdery product. Purification by column chromatography (eluent: toluene / hexane = 1/1: volume ratio) yielded 3.1 parts of intermediate (A1-1-1) (yellow solid).

(2) Synthesis of 2-[(phenyl) sulfinyl] thioxanthone [intermediate (A1-1-2)]:
While stirring 11.2 parts of intermediate (A1-1-1), 215 parts of acetonitrile and 0.02 part of sulfuric acid at 40 ° C., 4.0 parts of 30% aqueous hydrogen peroxide was gradually added dropwise to the mixture. After reacting at ˜45 ° C. for 14 hours, the reaction solution was cooled to room temperature (about 25 ° C.) and poured into 200 parts of distilled water to precipitate the product. This was filtered, and the residue was washed with water until the pH of the filtrate became neutral, and then the residue was dried under reduced pressure to obtain a yellow powdery product. The product was purified by column chromatography (eluent: ethyl acetate / toluene = 1/3: volume ratio) to obtain 13.2 parts of intermediate (A1-1-2) (yellow solid).

(3) Synthesis of sulfonium salt derivative (A1-1):
While stirring 4.3 parts of intermediate (A1-1-2), 4.1 parts of acetic anhydride and 110 parts of acetonitrile at 40 ° C., 2.4 parts of trifluoromethanesulfonic acid was gradually added dropwise to After reacting at 45 ° C. for 1 hour, the reaction solution is cooled to room temperature (about 25 ° C.), poured into 150 parts of distilled water, extracted with chloroform, and washed with water until the pH of the aqueous phase becomes neutral. did. After the chloroform phase was transferred to a rotary evaporator and the solvent was distilled off, 50 parts of toluene was added, dispersed in toluene with an ultrasonic cleaner, allowed to stand for about 15 minutes, and then the supernatant was removed three times to produce The washed solid was washed, and the residue was dried under reduced pressure. This residue was dissolved in 212 parts of dichloromethane, poured into 65 parts of a 10% potassium {tetrakis (perfluorophenyl)] borate} aqueous solution, and stirred at room temperature (about 25 ° C.) for 2 hours to separate the dichloromethane layer. The organic solvent was distilled off under reduced pressure to obtain 5.5 parts of a sulfonium salt derivative (A1-1) (yellow solid).

Production Example 2
[Synthesis of iodonium salt derivative (A2-1) {compound represented by chemical formula (22)} that generates an acid by actinic rays]

  6.5 parts of toluene, 8.1 parts of isopropylbenzene, 5.35 parts of potassium iodide and 20 parts of acetic anhydride are dissolved in 70 parts of acetic acid, cooled to 10 ° C., and kept at a temperature of 10 ± 2 ° C. A mixed solution of 12 parts of sulfuric acid and 15 parts of acetic acid was added dropwise over 1 hour. It heated up to 25 degreeC and stirred for 24 hours. Thereafter, 50 parts of diethyl ether was added to the reaction solution, washed with water three times, and diethyl ether was distilled off under reduced pressure. An aqueous solution in which 118 parts of potassium {trifluoro [tris (perfluoroethyl)] phosphate} was dissolved in 100 parts of water was added to the residue, followed by stirring at 25 ° C. for 20 hours. Thereafter, 500 parts of ethyl acetate was added to the reaction solution, washed 3 times with water, and the organic solvent was distilled off under reduced pressure to obtain 14.0 parts of the desired iodonium salt derivative (A2-1) (light yellow liquid). It was.

Examples 1-14 and Comparative Examples 1-4
Photoacid generators (A1-1), (A2-1), (A′-1), monofunctional cation polymerizable substances (B1-1), (B1-2) and polyfunctional cation polymerizable substances (B2- 1), (B2-2) is blended in the number of parts shown in Table 1, and mixed at 25 ° C. for 10 minutes using a rotating and rotating stirrer, and the actinic ray curable adhesive composition (Q-1) of the present invention. ) To (Q-14) and comparative actinic ray curable adhesive compositions (Q′-1) to (Q′-4) were produced.
The molecular weight of (B1-1) is 184, and the molecular weight of (B1-2) is 212.

The composition of the trade names in the table is as follows.
WPAG-336 (A′-1): diphenyl-4-methylphenylsulfonium trifluoromethanesulfonate (manufactured by Wako Pure Chemical Industries, Ltd.)

The actinic ray curable adhesive compositions obtained in Examples 1 to 14 and Comparative Examples 1 to 4 and cured products thereof were evaluated by the methods described below.
These evaluation results are shown in Table 1.

[Viscosity change rate]
The viscosity of each actinic ray curable adhesive composition obtained in Examples 1 to 14 and Comparative Examples 1 to 4 was 25 using an E type viscometer [manufactured by Toki Sangyo Co., Ltd., TVE-25 type viscometer]. The viscosity (p) at 0 ° C. was measured. 5 g of each actinic radiation curable adhesive composition obtained in Examples 1 to 14 and Comparative Examples 1 to 4 was placed in a polyethylene brown container (manufactured by NALGENE, 30 mL), sealed, and left at 25 ° C. for 2 weeks. . Using an E-type viscometer [manufactured by Toki Sangyo Co., Ltd., TVE-25 type viscometer], the viscosity (q) at 25 ° C. after 2 weeks was measured.
The viscosity change rate was calculated from the following formula.
Viscosity change rate (%) = {(q / p) -1} × 100

[Adhesive strength]
Thin glass with a thickness of 0.5 mm [manufactured by Central Glass Co., Ltd.] The same glass was used for the following evaluation. ] About 0.1 mL of each actinic ray curable adhesive composition obtained in Examples 1 to 14 and Comparative Examples 1 to 4 was applied on top, and a gap gauge [0.10 mm manufactured by Nagai Gauge Manufacturing Co., Ltd.] was applied. It was molded into a circular shape so as to have a film thickness of 100 μm with another slide glass prepared. The exposure was carried out using a belt conveyor type UV irradiation device (eye graphics Co., Ltd. “ECS-151U”, the same device was used for the following evaluation). The exposure amount was 1500 mJ / cm ² at 365 nm.
The adhesive strength of the round test piece after curing was evaluated with a tensile tester in accordance with JIS K-6849.

[Adhesive strength after heat test]
Using the actinic ray curable adhesive compositions obtained in Examples 1 to 14 and Comparative Examples 1 to 4, the test pieces for measuring the adhesive strength are prepared. After the 1000 hr test piece was subjected to a heat resistance test at 85 ° C., the test piece after the heat test was evaluated for adhesive strength with a tensile tester in accordance with JIS K-6849.
[Adhesive strength after moisture resistance test]
Using the actinic ray curable adhesive compositions obtained in Examples 1 to 14 and Comparative Examples 1 to 4, the test pieces for measuring the adhesive strength are prepared. A 1000 hr test piece was subjected to a moisture resistance test at 60 ° C. and 90% RH, and then the adhesive strength of the test piece after the moisture resistance test was evaluated by a tensile tester in accordance with JIS K-6849.

[Curing property]
Each actinic radiation curable adhesive composition obtained in Examples 1 to 14 and Comparative Examples 1 to 4 was applied onto a slide glass, and a belt conveyor type UV irradiation apparatus (“Egraphics Corporation“ ECS-151U ”, hereinafter). The same apparatus was also used for the evaluation of. The exposure amount was 1500 mJ / cm ² at 365 nm. After standing at room temperature for 5 minutes, the curability was evaluated in the following three stages.
The case where it was completely cured was evaluated as “◯”, the case where it was in a semi-cured state was evaluated as “Δ”, and the case where it was not cured at all was evaluated as “x”.

[Storage modulus of cured product]
Each actinic ray curable adhesive composition obtained in Examples 1 to 14 and Comparative Examples 1 to 4 was applied onto a PET film, and another one using a gap gauge [1.00 mm manufactured by Nagai Gauge Manufacturing Co., Ltd.]. The film was molded between a sheet of PET film to a thickness of 1 mm and a width of 5 mm, and was exposed using a belt conveyor type UV irradiation device to prepare a test piece for measuring storage elastic modulus.
This test piece was measured for storage elastic modulus (Pa) at 25 ° C. and a measurement frequency of 10 Hz using a viscoelasticity measuring device [UBM “Rheogel-E4000”].

All the adhesive compositions of Examples 1 to 14 of the present invention have a small rate of change in viscosity and good curability. The adhesive strength of those cured products, the adhesive strength after a heat test, and the adhesive strength after a moisture resistance test Excellent.
On the other hand, in Comparative Examples 1 and 2 not containing the photoacid generator (A) defined in the present invention, the resin was not cured, and the evaluation of the adhesive strength and the storage elastic modulus was not possible. Further, Comparative Example 3 not containing the polyfunctional cation polymerizable substance (B2) has a marked decrease in adhesive strength after the heat resistance test and after the moisture resistance test, and Comparative Example 3 not containing the monofunctional cation polymerizable substance (B1) is a change in viscosity. The rate has increased.

  The actinic ray curable adhesive composition of the present invention has high adhesive strength, excellent heat resistance and moisture resistance, and low curing shrinkage, so that it is used for flat panel displays, touch panels, and electronic component manufacturing. In particular, it is extremely useful for flat panel displays and touch panels.

Claims (6)

  An actinic ray curable adhesive composition comprising a photoacid generator (A) and a cationic polymerizable substance (B) comprising a monofunctional cationic polymerizable substance (B1) and a polyfunctional cationic polymerizable substance (B2) The photoacid generator (A) is a sulfonium salt derivative (A1) or an iodonium salt derivative (A2), and the anion thereof is a hexafluorophosphate anion, a trifluoro [tris (perfluoroethyl)] phosphate anion, or a tetrakis (par An actinic ray curable adhesive composition, which is a fluorophenyl) borate anion and has a weight ratio of (B2) / (B1) of 0.01 to 1.   The actinic ray curable adhesive composition according to claim 1, wherein the content of the photoacid generator (A) with respect to the cationic polymerizable substance (B) is 0.05 to 30% by weight. The actinic ray curable adhesive composition according to claim 1, wherein the storage elastic modulus at 25 ° C. after curing is 1 × 10 ³ to 1 × 10 ⁶ Pa.   The actinic ray curable adhesive composition according to any one of claims 1 to 3, comprising a polymerizable substance having a molecular weight of 150 to 1,000 as the monofunctional cationic polymerizable substance (B1).   The actinic ray curable adhesive composition according to any one of claims 1 to 4, which is used for flat panel displays, touch panels, or electronic component manufacturing. A cured product obtained by curing the actinic ray curable adhesive composition according to claim 1 by irradiation with actinic rays.