JP6512892B2 - Curable resin composition and cured product using the same - Google Patents

Description

  The present invention is a curable resin composition capable of providing a cured product capable of maintaining excellent adhesion and colorless transparency even when exposed to high temperature and high humidity for a long time, and a cured product of the curable resin composition and the cured product The present invention relates to an image display apparatus including an object.

  Heat resistance and chemical resistance for the application of protective sheets to display screens, bonding of various functional optical sheets, and filling of gaps between optical device members in optical displays such as liquid crystal displays and organic EL displays. In general, a curable resin composition having electrical properties such as insulation, adhesion, and transparency is used.

  (Meth) acryloyl group-containing polymers and / or (meth) acrylate compounds having a polymerizable functional group such as an acryloyl group or a methacryloyl group (these are generally referred to as “(meth) acryloyl group” when not particularly distinguished) A curable resin combined with a meth-) acrylate-based polymerizable monomer is capable of precisely controlling the curing reaction, and further, in terms of electrical characteristics such as heat resistance, chemical resistance and insulation, adhesion, and transparency. It is generally known as an adhesive and a filler used in the above-mentioned optical device and the like because an excellent cured product can be obtained.

  A curable resin combined with a polymerizable monomer such as a (meth) acryloyl group-containing polymer and / or a (meth) acrylate compound causes shrinkage due to a curing reaction, so when used as a filler or an adhesive in the above optical display As a result of curing shrinkage, display performance may be reduced. Moreover, curable resin which combined polymeric monomers, such as a (meth) acryloyl group containing polymer and / or a (meth) acrylate compound, tends to be inferior to adhesiveness on low energy surfaces, such as polyolefin. For this reason, it is common practice to use a non-reactive resin in combination.

  For example, in JP 2012-162705 A (patent document 1), a rosin ester resin is used as a plasticizer for a curable resin comprising a combination of a (meth) acryloyl-modified polymer of a polyether polyol and a (meth) acrylate compound. And the inclusion of polyether polyols are disclosed.

Further, JP-A-2014-189758 (Patent Document 2) is a photocurable resin which is excellent in transparency, excellent in durability such as heat resistance, light resistance and moisture resistance, and can provide a cured product having a low dielectric constant. As a resin composition, an energy ray-curable resin composition has been proposed which contains a (meth) acryloyl-modified conjugated diene-based polymer, a (meth) acrylate monomer having a hydrophilic group, and a photopolymerization initiator.
In the examples, a rosin ester-based resin (rosin ester “KE-311” manufactured by Arakawa Chemical Industries, Ltd.) containing few impurities is used in combination as a non-reactive tackifier (paragraph 0149).

  Furthermore, in JP-A-2006-45474 (Patent Document 3), in a photopolymerizable acrylic pressure-sensitive adhesive composition containing an acrylate-based monomer mixture and a photopolymerization initiator, a predetermined weight average molecular weight as a tackifying resin is obtained. It has been proposed to use (meth) acrylate polymers having solubility parameters and glass transition temperatures. In Examples, isobornyl acrylate polymer is used as a tackifying resin, and it is disclosed that such a resin composition is excellent in transparency and excellent in adhesiveness.

JP-A 2008-174658 (Patent Document 4) discloses adhesion to a pressure-sensitive adhesive composition containing a copolymer of N-vinylcarboxylic acid amide and (meth) acrylic acid ester, and a crosslinking agent. A composition using a (meth) acrylic acid ester-based polymer or the like as a tackifying resin to be enhanced is disclosed (paragraph 0027).
In the examples, an acrylic pressure-sensitive adhesive composition containing an isobornyl acrylate polymer as the (meth) acrylic acid ester-based polymer is excellent in adhesion and reworkability, and further 30 in an autoclave at 50 ° C. × 0.5 MPa. It was shown that no peeling or lifting was observed in the durability test in which the treatment was conducted for a minute and then for 500 hours in an environment of 60 ° C. × 90% RH (paragraphs 0053-0055, 0057, 0058, Table 1).

  As described above, in the curable resin composition using the (meth) acryloyl group-containing polymer and / or the (meth) acrylate-based monomer, in order to improve the transparency, adhesiveness, and durability, (meth) acryloyl group Various resin compositions have been proposed in which the structure of the contained polymer and the non-reactive resin used in combination are devised.

JP, 2012-162705, A JP, 2014-189758, A Unexamined-Japanese-Patent No. 2006-45474 JP, 2008-174658, A

  By the way, in recent years, the demand for colorless transparency of an optical display is becoming more and more severe. In particular, in an on-vehicle optical display such as a car navigation system, the interior temperature of the vehicle rises to a high temperature of 80 ° C. or more, and may be left for a long time in such a state. Even when left at such a high temperature for a long time, it is required that the decrease in the adhesive strength and the optical characteristics be small.

  Rosin acid derivatives such as rosin acid esters generally used for the purpose of imparting plasticity or tackiness to a curable resin composition in which a polymerizable monomer such as a (meth) acryloyl group-containing polymer and / or a (meth) acrylate compound is combined Non-reactive resins derived from natural substances such as modified rosin resins, terpene resins, terpene phenol resins, C5 and C9 petroleum resins, and coumarone resins are colored in yellowish brown. For this reason, improvements are required for applications such as displays where the requirement for colorless transparency is severe. In this regard, in recent years, ultra-light-colored rosin and its derivatives that can be said to be colorless have been developed and marketed. [KE-311] of Arakawa Chemical Industry Co., Ltd. used in the example of Patent Document 2 is an example.

However, in Patent Document 2, the durability is heat resistance based on the presence or absence of discoloration after heating for 250 hours in an oven at 100 ° C., light resistance of visually confirming discoloration after light irradiation at 200 MJ / m ² , 85 ° C. And the turbidity after holding for 100 hours at 85% RH is only evaluated by the moisture resistance visually confirmed (Paragraph 0135-0138). The durability required for the in-vehicle display device is insufficient for the durability satisfying the above evaluation criteria.

  Although the said patent document 3 uses non-reactive resin which consists of a synthetic polymer which is excellent in transparency, the evaluation remains in the evaluation of the adhesive force in a normal temperature, and an external appearance from a relation with an adhesive use. It is difficult to apply to adhesives and fillers used in display devices for vehicles such as car navigation systems.

  Although the durability is evaluated in Patent Document 4, it remains in the evaluation of the durability of the adhesive strength under high humidity conditions such as treatment for 500 hours under an environment of 60 ° C. × 90% RH (paragraph 0058). It can not be applied to applications requiring high heat resistance and durability with less deterioration of adhesive strength and optical characteristics even when left for a long time under high temperature as in a car display.

  The present invention has been made in view of the above circumstances, and the object of the present invention is a curable resin composition that can satisfy severe durability that can be suitably used for a display device mounted on a vehicle. It is to provide.

That is, the curable resin composition of the present invention, (A) a conjugated diene polymer units selected from hydrogenated polybutadiene and hydrogenated polyisoprene down or Ranaru group comprises one or more, and the main chain and / Or a polymer whose side chain is α, β-unsaturated carbonyl modified (hereinafter referred to as “α, β-unsaturated carbonyl modified diene polymer”);
(B) (meth) acrylate compounds ;
(C) an alicyclic skeleton-containing polymer having a number average molecular weight of 5,000 to 80,000 having a repeating unit of the following formula (11) ;
(D) contains polybutene and / or polyisobutylene having a number average molecular weight of 300 to 1,500 .

In formula (11), Rc is an alicyclic skeleton-containing group, and R ¹⁰ and R ¹¹ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an allyloxyalkyl group having 1 to 6 carbon atoms.
Further, the alicyclic skeleton contained in Rc is preferably a polycyclic system.

The glass transition temperature before the SL (C) alicyclic skeleton-containing polymer (Tg) of preferably at 50 ° C. or higher.

Wherein the front SL (C) alicyclic skeleton-containing polymer (D) a polybutene and / or contained mass ratio of polyisobutylene (C: D) is 85: 15 to 5: is preferably 95. The total content of the (C) alicyclic skeleton-containing polymer and the (D) polybutene and / or polyisobutylene is preferably 1 to 90% by mass of the total amount of resin components.
In addition, the (C) alicyclic skeleton-containing polymer and (D) polybutene and / or polyisobutylene are (C) alicyclic skeletons produced by performing a polymerization reaction using (D) polybutene and / or polyisobutylene as a solvent. It is preferable that it is a containing polymer solution.

  The total content of the (A) α, β-unsaturated carbonyl-modified diene polymer and the (B) (meth) acrylate compound is preferably 10 to 99% by mass of the total amount of resin components.

The initial yellowness (YI ₀ ) of the cured product obtained by curing the curable resin composition of the present invention is 1.0 or less, and the yellowness after exposure at 105 ° C. for 1000 hours ( It is preferable that YI ₁₀₀₀ ) is 1.9 or less.
In addition, the initial haze (H ₀ ) of the cured product obtained by curing the curable resin composition of the present invention is 0.5% or less, and the haze after exposure to an environment at 85 ° C. and 85% RH for 1000 hours. (H ₁₀₀₀ ) is preferably 2.0% or less.

  The present invention also includes a cured product obtained by curing the curable resin composition of the present invention by energy ray irradiation, and an image display device having the cured product.

  The curable resin composition of the present invention is excellent in adhesion and colorless transparency, and in particular, is less susceptible to yellowing, clouding and excellent in adhesion even when held for a long time under high temperature and high humidity. ing.

  The description of the configuration requirements described below is an example (representative example) of the embodiment of the present invention, and is not specific to these contents.

<Energy ray curable resin composition>
The curable resin composition of the present invention is
(A) A conjugated diene-based polymer unit selected from the group consisting of hydrogenated polybutadiene, hydrogenated polyisoprene and polyisoprene, containing one or more conjugated diene polymer units, and the main chain and / or side chain being α, β-non Polymer which is saturated carbonyl modified (hereinafter referred to as “α, β-unsaturated carbonyl modified diene polymer”);
(B) (meth) acrylate compounds ;
(C) an alicyclic skeleton-containing polymer ;
(D) containing polybutene and / or polyisobutylene .
Each component will be described below.

(A) One or more conjugated diene-based polymer units selected from the group consisting of hydrogenated polybutadiene units, hydrogenated polyisoprene units, and polyisoprene units, and the main chain and / or side chains are α, β- Polymer which is unsaturated carbonyl modified (hereinafter "α, β-unsaturated carbonyl modified diene polymer")

  Hydrogenated polybutadiene is obtained by hydrogenating polybutadiene synthesized by subjecting butadiene to 1,2-addition polymerization and / or 1,4-addition polymerization. The hydrogenation may be a partial hydrogenation agent as long as the compatibility with the alicyclic skeleton-containing polymer which is the component (C) and the transparency of the cured product are not impaired. In addition, Formula (1) has shown the hydrogenated polybutadiene (completely hydrogenated substance) unit mentioned as an example. In the formula (1), p and q are each an integer of 0 to 100, and p + q is an integer of 10 to 150.

  Polyisoprene is obtained by addition polymerization of isoprene, and may be any of 1,4-addition polymer, 1,2-addition polymer, and 3,4-addition polymer, and in the case of 1,4-addition polymer, It may be cis or trans. The polyisoprene unit may or may not be hydrogenated, and may be either fully hydrogenated or partially hydrogenated if it is hydrogenated.

The α, β-unsaturated carbonyl-modified diene polymer which is the component (A) contains one or more hydrogenated polybutadiene units, hydrogenated polyisoprene units, and polyisoprene units as described above.
When only one unit is contained, it is referred to as α, β-unsaturated carbonyl modified mono-unit type diene polymer, and when it contains 2 or more units, α, β-unsaturated carbonyl modified multi-unit type diene polymer Call it and distinguish it if necessary. When simply referred to as "[alpha], [beta] -unsaturated carbonyl-modified diene polymer", both mono- and multi-unit types are included.

  The α, β-unsaturated carbonyl-modified diene polymer comprises a conjugated diene polymer polyol (a conjugated diene polymer polyol (a-1) or a conjugate thereof (a-1 ′)) having a corresponding conjugated diene polymer unit , [Alpha], [beta] -unsaturated carbonyl compound (a-2).

(A-1) Conjugated Diene-Based Polymer Polyol The conjugated diene-based polymer polyol is a hydrogenated polybutadiene, a hydrogenated polyisoprene, or a compound having two or more hydroxyl groups in the main chain or side chain of polyisoprene. Preferably, it is a (hydrogenated) conjugated diene-based polymer polyol of a terminal hydroxyl group-containing type having a hydroxyl group at the main chain terminal.

The linked product (a-1 ') of (a-1') and (a-1) is obtained by polymerizing the (a-1) conjugated diene-based polymer polyol by reaction with a linking compound.

(Compound for linking)
The linking compound is a compound having two or more functional groups L capable of reacting with the hydroxyl group of the (hydrogenated) conjugated diene polymer polyol (a-1), and, for example, a bifunctional compound represented by the following formula (2a) The trifunctional compound represented by (2b), the tetrafunctional compound represented by (2c) are mentioned. Preferably it is a bifunctional compound. In formulas (2a), (2b) and (2c), L is a functional group that reacts with a hydroxyl group, and M, M ′ and M ′ ′ are organic groups.

  Specific examples of the functional group L include (i) an isocyanate group, (ii) a carboxyl group (including a halogenated carbonyl group and an ester), and (iii) an epoxy group. In addition, as the organic groups M, M ′ and M ′ ′, any of aliphatic, aromatic and alicyclic groups having the above functional groups and having 2, 3 and 4 free bonds may be used, From the viewpoint of reactivity and compatibility with the component (a-1), aliphatic and alicyclic groups having 2 to 18 carbon atoms, preferably 3 to 15, and particularly preferably 8 to 12 carbon atoms are preferable.

(I) Isocyanate Group-Containing Linking Compound The isocyanate group-containing linking compound is an aliphatic or aromatic polyisocyanate having 2 or more, preferably 2 to 4 isocyanate groups, preferably a diisocyanate.

Examples of the diisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate (1,6-diisocyanatohexane), octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate; lysine diisocyanate, tetramethyl xylylene diisocyanate, Aliphatic diisocyanates such as trimethylhexane diisocyanate or derivatives of tetramethylhexane diisocyanate; 1,4-, 1,3- or 1,2-diisocyanatocyclohexane, 4,4'- or 2,4'-di (isocyanato) Cyclohexyl) methane, 1-isocyanato-3,3,5-trimethyl-5- (isocyanatomethyl) cyclohexane (isophorone diisocyanate) And cycloaliphatic diisocyanates such as 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane or 2,4- or 2,6-diisocyanato-1-methylcyclohexane; 2,4- or 2,6 Tolylene diisocyanate, m- or p-xylylene diisocyanate, 2,4'- or 4,4'-diisocyanatodiphenylmethane, 1,3- or 1,4-phenylene diisocyanate, 1-chloro-2,4- Phenylene diisocyanate, 1,5-naphthylene diisocyanate, diphenylene 4,4'-diisocyanate, 4,4'-diisocyanato-3,3'-dimethylbiphenyl, 3-methyldiphenylmethane 4,4'-diisocyanate or diphenyl ether 4,4 ' And aromatic diisocyanates such as diisocyanates.
A triisocyanate such as tris (4-isocyanatophenyl) thiophosphate and a tetraisocyanate such as 1,3,5,7-adamantanetetrayl tetraisocyanate may be used.

(Ii) Carboxyl group-containing linking compound As a linking compound having two or more carboxyl groups, dicarboxylic acid, tricarboxylic acid, polycarboxylic acid, or anhydrides or esters thereof; pyridine 2, 6-dicarboxylic acid dichloride and the like Halogenated carbonyl group-containing linking compounds and the like can be used, and these are saturated aliphatic carboxylic acids, unsaturated carboxylic acids, substituted carboxylic acids in which a hydrogen atom other than a carboxyl group is substituted with a halogen, a hydroxyl group, a carbonyl group, etc. It is a saturated carboxylic acid having 2 to 18, preferably 3 to 15, and more preferably 8 to 12 carbon atoms, such as aromatic carboxylic acid. Among these, preferred are dicarboxylic acids or esters thereof.

  Specifically, as dicarboxylic acids, saturated dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, citric acid, propane tricarboxylic acid, or These anhydrides, or these C1-C20 alkyl esters; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, maleic anhydride, citraconic acid, mesaconic acid, etc .; aromatic dicarboxylic acids such as phthalic acid etc. Be

(Iii) Epoxy group-containing linking compound The epoxy group-containing linking compound has, as a functional group capable of reacting with a hydroxyl group, two or more three-membered ring structures (epoxy group, oxirane group, glycidyl group, etc.) consisting of carbon and oxygen atoms. And an epoxy resin obtained by reacting bisphenol A, bisphenol F or a hydrogenated product thereof with epichlorohydrin, and having 2 to 18 carbon atoms, preferably 3 to 15, and more preferably 8 to 8 carbon atoms. Twelve epoxy resins are preferably used. Specifically, bisphenol A diglycidyl ether, diglycidyl ether or the like can be used.

(Linking reaction)
The (hydrogenated) conjugated diene-based polymer polyol is linked and multimerized by the reaction of the (a-1) (hydrogenated) conjugated diene-based polymer polyol and the above-described connecting compound. A linked product of (hydrogenated) conjugated diene-based polymer polyols is referred to as "multi-unit type diene-based polymer".

  (Hydrogenization) The multimerization of the conjugated diene polymer polyol (a-1) is carried out by using a bond formed by the reaction of the hydroxyl group of the polyol (a-1) with the functional group L of the compound for connection as a linking portion. It will be. Accordingly, when the linking compound is (i) an isocyanate group-containing linking compound, it reacts with the hydroxyl group of the conjugated diene-based polymer polyol (a-1) to form a urethane bond. When the linking compound is (ii) a carboxyl group-containing linking compound, it reacts with the hydroxyl group of the diene polymer polyol (a-1) to form an ester bond. When the linking compound is (iii) an epoxy group-containing linking compound, it reacts with the hydroxyl group of the diene polymer polyol (a-1) to open the epoxy ring to form an ether bond.

  As described above, depending on the type and amount of the linking compound, a dimerized, trimerized or tetramerized polyol multimer is obtained. The reaction of the linking compound with the diene polymer polyol (a-1) is carried out under conditions which do not cause gelation due to rapid multimerization. In general, conditions that do not cause gelation can be appropriately selected depending on the type of reaction catalyst, adjustment of the charged amount ratio of the polyol and the linking compound, adjustment of the reaction temperature, a charging rate (dropping rate), and the like.

  Hereinafter, the multi-unit type diene-based polymer obtained by multimerization will be described focusing on the case where a typical bifunctional type (L-ML) is used as a linking compound.

When it is multimerized using one kind of (hydrogenated) conjugated diene-based polymer polyol, the equivalent ratio of the diene-based polymer polyol (a-1) to be subjected to the synthesis reaction to the compound for linking is represented by the following formula As shown in (3a) or (3b), a multi-unit type diene-based polymer in which one type of (hydrogenated) conjugated diene-based polymer unit is linked by a linking portion is obtained. In the formula, n ₁ and n ₂ are each independently an integer of 1 to 20.

  Formula (3a) shows the case where the diene polymer polyol is excessive (the terminal functional group becomes -OH derived from the polymer polyol), and the formula (3b) shows the compound when the linking compound is excessive (the terminal functional group is the linking compound It becomes L of origin).

  When two or three (hydrogenated) conjugated diene-based polymer polyols (a-1) are subjected to a coupling reaction, for example, two diene-based polymer polyols are used, and when the diene-based polymer polyols are in excess, As shown in the following formula (4), a multi-unit type diene-based polymer having 1 and m + 1 units of (hydrogenated) conjugated diene-based polymer 1 and (hydrogenated) conjugated diene-based polymer 2 is obtained. When the coupling reaction is carried out using different types of (hydrogenated) conjugated diene-based polymer polyols, the content ratio (l: m + 1) of each polymer unit is adjusted by the preparation ratio at the time of synthesis reaction, and (hydrogenated) conjugated The mode of linkage of the diene-based polymer units may be a random type randomly linked, or may be a block type in which (hydrogenated) conjugated diene-based polymer units of the same type are linked.

  In the formulas (3a), (3b) and (4), Z is a bond generated as a result of the reaction of the functional group L of the linking compound to be used with a hydroxyl group, and is a urethane bond, an ester bond or an ether bond. It is preferably a urethane bond or an ester bond, more preferably a urethane bond.

  When a trifunctional linking compound is used as the linking compound, or when a polyol having three or more hydroxyl groups is used as the diene polymer polyol (a-1), the following formula (5a), ( As in 5b), multimerization occurs in three dimensions.

  The end of the multi-unit diene polymer depends on the equivalent ratio of the polymer polyol (a-1) to be subjected to the synthesis reaction and the linking compound. (4) Formula (5) shows the case where the hydroxyl group equivalent of (i) diene type polymer polyol is excessive and the terminal of the multi-unit type diene type polymer obtained is hydroxyl group, but (ii) for connection When the functional group L of the compound is in excess, the terminal of the resulting multi-unit type diene-based polymer is the functional group L.

(A-2) α, β unsaturated carbonyl compound ((meth) acryloylating agent)
Α, β-unsaturated carbonyl compound (a−) used for α, β-unsaturated carbonyl modification of mono-unit type (hydrogenated) conjugated diene polymer polyol (a-1) or its conjugate (a-1 ′) 2) is an α, β-unsaturated carbonyl compound of which general formula is represented by the following formula (6). (6) In the formula, Q is a functional group that reacts with the terminal functional group (hydroxyl group or functional group L of the compound for linking) of the mono-unit type conjugated diene polymer polyol (a-1) or its conjugate (a-1 ') Or a group having the functional group, or a halogen.

(I) When the terminal functional group is a hydroxyl group As a functional group which reacts with a hydroxyl group, an isocyanate group, a carboxyl group (a halogenated carbonyl group, an ester is included), an epoxy group is mentioned.
Accordingly, as the α, β-unsaturated carbonyl compound (a-2) having a functional group capable of reacting with a hydroxyl group, an isocyanate group-containing unsaturated carbonyl compound represented by the general formula (7a); represented by the general formula (7b) Carboxyl group-containing unsaturated carbonyl compound; epoxy group-containing unsaturated carbonyl compound represented by the general formula (7c); Q is -OH or -OR (R is a linear or branched alkyl group having 1 to 20 carbon atoms or A corresponding carboxylic acid or carboxylic acid ester which is an aryl group); a carboxylic acid halide in which Q is a halogen.

In the above general formulas (6) and (7a) to (7c), R ¹ and R ² each represent hydrogen or a linear or branched alkyl group having 1 to 6 carbon atoms such as methyl, ethyl or propyl. And R ¹ and R ² may be the same or different.

  In the formulas (7a) to (7c), X is an intervening group, and is a linear or branched alkylene group having 1 to 6 carbon atoms such as methylene, ethylene, propylene, trimethylene, tetramethylene, etc., preferably methylene, It is ethylene.

  As the isocyanate group-containing unsaturated carbonyl compound represented by the formula (7a), 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate, 1,1-bis (acryloyloxymethyl) ethyl isocyanate, etc. It can be mentioned.

  As the carboxyl group-containing unsaturated carbonyl compound represented by the formula (7b), (meth) acryloyloxycarboxylic acid such as 2-acryloyloxyethyl succinic acid can be used.

  As the epoxy group-containing unsaturated carbonyl compound represented by (7c), (meth) acrylic acid glycidyl ester can be used.

  Examples of carboxylic acids or carboxylic esters in which Q is —OH or —OR (R is a linear or branched alkyl group having 1 to 20 carbon atoms) include carboxylic acid compounds such as (meth) acrylic acid; ) Methyl acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert (meth) acrylate -Butyl, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, (meth) acrylic 2-ethylhexyl acid, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, (meth Phenyl acrylate, (meth) toluyl acrylate, or the like can be used (meth) benzyl acrylate.

  In addition, when Q is a halogen, unsaturated acid halides such as (meth) acrylic acid and (meth) acrylic acid bromide can be used.

(Ii) In the case where the terminal functional group is the functional group L derived from the compound for linking As the α, β unsaturated carbonyl compound (a-2) having a functional group that reacts with the functional group L, The corresponding unsaturated carboxylic acids or unsaturated carboxylic acid hydroxyesters represented by the general formula (8b) are applicable. In the formula (8b), R (OH) is a hydroxylalkyl group in which one of the hydrogen atoms of linear or branched alkyl having 1 to 6 carbon atoms is substituted by a hydroxyl group.

  Accordingly, when Q is -OH, examples of the α, β-unsaturated compounds represented by the formula (8a) include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, tiglic acid and angelic acid. Among these, acrylic acid and methacrylic acid are preferably used.

  In the case of an α, β-unsaturated carbonyl compound in which Q is an atomic group containing R (OH) as represented by the formula (8b), 2-hydroxyethyl (meth) acrylate, (meth) acryl Unsaturated carboxylic acid hydroxy esters such as 2-hydroxypropyl acid are included.

As the α, β-unsaturated carbonyl compound having the above constitution, an α, β-unsaturated carbonyl group is preferably an acryloyl group or a methacryloyl group in which R ¹ is hydrogen or methyl and R ² is hydrogen. Hereinafter, in the case where the α, β-unsaturated carbonyl group is a (meth) acryloyl group, the case where the “(meth) acryloylating agent” is used will be described as a representative.

[Synthesis of α, β-unsaturated carbonyl-modified diene polymer: reaction of conjugated diene polymer polyol (a-1) or its conjugate (a-1 ′) with unsaturated carbonyl compound (a-2)]
By reacting the above-mentioned conjugated diene-based polymer polyol (a-1) or its conjugate (a-1 ′) with the above α, β-unsaturated carbonyl compound ((meth) acryloylating agent) (a-2) , Α, β-unsaturated carbonyl modified diene polymers are synthesized.

  Terminal functional group (functional group L derived from hydroxyl group or linking compound) of diene polymer polyol (a-1) or its conjugate (a-1 ') and (meth) acryloylating agent (a-2) The functional groups inside react with each other to form a bond, and the terminal of the diene polymer unit is capped with a (meth) acryloyl group as represented by the following general formula (9).

  In the formula (9), Y is a terminal functional group (-OH or L) of a diene polymer polyol (a-1) or a linked product (a-1 ') and an α, β unsaturated carbonyl compound (a-2) And a linkage-containing group which is produced as a result of reaction with the functional group of (a), and depending on the kind of compound and functional group used, a urethane bond, an ester bond, an ether bond or an organic group contained in these bonds Become.

  Among the α, β-unsaturated carbonyl modification reactions as described above, preferably a conjugate (a-1 ′) whose terminal functional group is a hydroxyl group, and a (meth) acryloylating agent are represented by the formula (7a) This is a reaction using an isocyanate-containing (meth) acrylate, and an α, β-unsaturated carbonyl modified product represented by the following formula (10) is obtained.

  In the formula, the diene-based polymer unit is a diene-based polymer unit or a linked product of two or more diene-based polymer units. In the case where the linked body (a-1 ′) contains a plurality of types of diene-based polymer units, a multi-unit type diene-based polymer in which the diene-based polymer unit in the formula (10) also contains a plurality of types of diene-based polymer units It becomes.

  The reaction for introducing an α, β-unsaturated carbonyl group into a (hydrogenated) conjugated diene polymer (α, β-unsaturated carbonyl modification reaction) is usually carried out in the presence of a solvent. In the composition of the present invention, since the (meth) acrylate compound which is the component (B) is usually a liquid at normal temperature, it can be used as a reaction solvent for the component (A). It becomes possible to use the product obtained by the synthesis as a mixture of the (A) component and the (B) component without an operation such as solvent removal. This has the advantage that not only the process of solvent removal operation can be simplified but also the inclusion of impurities such as residual solvent derived from the component (A) in the composition can be avoided. Since the remaining solvent may cause voids in the cured product, the use of the solvent other than the essential components of the composition is avoided by using the component (A) to make the adhesive layer transparent and improve the image quality. You can expect the effect.

  The number average molecular weight and viscosity of the unsaturated carbonyl-modified diene polymer (A) to be obtained vary depending on the type of diene unit to be a repeating unit, the presence or absence of multimerization, etc., but generally the molecular weight and viscosity increase in multi-unit type The molecular weight and viscosity further increase with the increase of the diene-based polymer unit.

  The number average molecular weight (Mn) of the component (A) depends on the type of (hydrogenated) conjugated diene contained and the number of diene polymer units contained, but is preferably 3000 to 50000, preferably 4000 to 40000, more preferably Is a high molecular weight compound of 5,000 to 30,000, more preferably 5,000 to 20,000. The viscosity at 25 ° C. varies depending on the type of the (hydrogenated) conjugated diene-based polymer unit, the number thereof, the reaction conditions and the like, but is 5 to 2000 Pa · s, preferably 8 to 1500 Pa · s.

  In addition, the number average molecular weight said to this specification is the value measured using gel permeation chromatography (solvent: tetrahydrofuran). The viscosity can be measured using a B-type viscometer (type “RB80L”: manufactured by Toki Sangyo Co., Ltd.) at a temperature of 25 ° C.

  The α, β-unsaturated carbonyl-modified diene polymer used as the component (A) in the present invention is an α, β-unsaturated carbonyl having two or more α, β-unsaturated carbonyl groups per molecular chain of the polymer It may be a mixture of a modified diene polymer and an α, β-unsaturated carbonyl modified diene polymer having only one α, β-unsaturated carbonyl group per molecular chain of the polymer. It is preferable to have an average of 1.5 or more α, β-unsaturated carbonyl groups per polymer molecular chain as the entire α, β-unsaturated carbonyl modified (hydrogenated) conjugated diene polymer.

  The content of the component (A) as described above is preferably 5 to 50% by mass, more preferably 5 to 30%, based on the total content of the resin component as 100 in the resin component contained in the composition. %, More preferably 5 to 20% by mass. If the content is 5% by mass or less, the content of the (C) alicyclic skeleton-containing polymer becomes relatively high, curing becomes insufficient, and the cured product becomes too soft. If it exceeds 50% by mass, the content of the (C) alicyclic skeleton-containing polymer becomes relatively small, and the heat resistance and the adhesiveness are insufficient.

  In addition, when the resin component said to this specification contains (A) component, (B) component, and (C) component which may exist as resin in hardened | cured material, and also (D) component, it is (D) component. In addition, when it contains other non-reactive resin, it means other non-reactive resin. Therefore, the term “total resin component amount” refers to the total amount of these components.

(B) (Meth) Acrylate Compound The (meth) acrylate compound is used as a polymerizable compound which can be co-cured with the α, β-unsaturated carbonyl-modified diene polymer which is the component (A).

  As the (meth) acrylic acid ester, for example, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate and the like having 6 to 20 carbon atoms Alkyl group-containing (meth) acrylates; cyclohexyl (meth) acrylates, norbornyl (meth) acrylates, isobornyl (meth) acrylates, norbornanyl (meth) acrylates, dicyclopentenyl (meth) acrylates, dicyclopentenyl oxyethyl (meth) Cycloalkyl group-containing (meth) acrylates such as acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyl oxyethyl (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate; And (meth) acrylates having substituents other than alkyl groups or cycloalkyl groups such as lu-2-allyloxymethyl acrylate and 2-hydroxypropyl acrylate. These may be used alone or in combination of two or more.

  Among these, a cycloalkyl group-containing (meth) acrylate is preferably used from the viewpoint of compatibility with the alicyclic skeleton-containing polymer which is the component (C). Moreover, it is preferable to use a hydroxy containing (meth) acrylate from a viewpoint of moisture resistance provision.

The content of the (B) (meth) acrylate compound is preferably 5 to 50% by mass, more preferably 8 to 30% by mass, and still more preferably 10 to 30% by mass in the resin component of the composition. is there.
The total content of the components (A) and (B) is preferably 10 to 99% by mass, more preferably 20 to 80% by resin, of the total amount of resin components contained in the composition. Preferably it is 30-50 mass%.

(C) Alicyclic skeleton-containing polymer The alicyclic skeleton-containing polymer used in the present invention is a polymer having a repeating unit of the following formula (11), and corresponds to a non-reactive resin having no polymerizable functional group.

In the formula, R ¹⁰ and R ^{11 each} independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl or hexyl, or allyloxymethyl, allyloxyethyl or allyl. They are allyloxy alkyl groups (C1-C6 alkyl group) such as oxypropyl, allyloxybutyl, allyloxypentyl and the like, preferably a hydrogen atom and a methyl group.

  In the formula, Rc represents an alicyclic skeleton-containing group. The alicyclic skeleton may be any of a single ring and a polycyclic system of two or more members, and in the case of a polycyclic system, may have a crosslinked structure. Furthermore, as long as the polymerization reactivity of the alicyclic skeleton is not impaired, the alicyclic skeleton may have a substituent such as a lower alkyl group such as a methyl group. Furthermore, the substituent may be contained as an intervening organic group between the "Rc-O" bond.

  Alicyclic skeleton-containing polymers include alicyclic compounds (eg, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptan, cyclooctane, methylcyclopentane, 1,2-dimethylcyclopentane, methylcyclohexane, cyclopentene, etc. Monocyclic compounds; bicyclo [2.2.1] heptan norbornane, tricyclo [2.2.1.0] heptannortricyclene, dicyclopentanyl, polycyclic compounds such as adamantane, busketane, etc. and (meth) acrylics It is obtained by polymerizing an alicyclic compound ester of (meth) acrylic acid consisting of an ester with an acid.

  Examples of alicyclic compound esters of (meth) acrylic acid include monocyclic (meth) acrylates such as cyclopropyl (meth) acrylate, cyclobutyl (meth) acrylate, cyclopentyl (meth) acrylate, and cyclohexyl (meth) acrylate. Acrylate; dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl oxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyl oxy (meth) acrylate, tri Cyclodecane dimethylol di (meth) acrylate, 1,7,7-trimethylbicyclo [2.2.1] hept-2-yl acrylate (hereinafter referred to as “isobornyl (meth) acrylate”), norbornyl (meth) acrylate, Isobornyl (Meta) Crylates and norbornanyl (meth) acrylates can be mentioned.

The polymerization reaction can be carried out by a conventionally known method, that is, by polymerizing an alicyclic compound ester of (meth) acrylic acid in an organic solvent, and after polymerization, it may be degassed.
In the above polymerization reaction, it is preferable to use a chain transfer agent. As a chain transfer agent, for example, it is preferable to use a compound having a mercapto group such as mercapto carboxylic acids, mercapto carboxylic esters, alkyl mercaptans, mercapto alcohols, aromatic mercaptans, mercapto isocyanurates and the like. More preferred are alkyl mercaptans, mercapto carboxylic acids, and mercapto carboxylic esters, and more preferred is n-dodecyl mercaptan.
The type of organic solvent used in the above polymerization is not particularly limited, and alcohols such as methanol, ethanol and propanol; acetates such as methyl acetate and ethyl acetate; ethers such as dimethyl ether and ethylene glycol methyl ether; acetone and methyl ethyl ketone And the like; and various known organic solvents such as toluene, cyclohexanone and methyl cellosolve can be used. When the resin composition of the present invention contains (D) polybutene and / or polyisobutylene described later, it is preferable to use the component (D) as a solvent. Thereby, the degassing process performed after superposition | polymerization becomes unnecessary, and it can use for preparation of a composition as it is.

The number average molecular weight of the (C) alicyclic skeleton-containing polymer is preferably 5,000 to 8,000, more preferably 5,000 to 50,000, and still more preferably 5,000 to 30,000.
If the molecular weight is too low, it is difficult to obtain desired heat resistance and adhesion. On the other hand, if the molecular weight is too high, the viscosity of the composition will be high, and the compatibility with other components will decrease, so the light transmittance of the resulting cured product tends to decrease. Furthermore, when the molecular weight exceeds 100,000, preparation of the composition itself becomes difficult due to the high viscosity, and furthermore, the compatibility may be reduced, and the resin composition may become turbid.

  Further, the glass transition temperature (Tg) of the (C) alicyclic skeleton-containing polymer is preferably 50 ° C. or more, more preferably 70 ° C. or more, and still more preferably 90 ° C. or more. Therefore, the (C) alicyclic skeleton-containing polymer is usually solid alone at normal temperature. However, the polymer solution can be used by appropriately selecting the solvent.

Such an alicyclic skeleton-containing polymer can act as a tackifying resin in a curable resin composition of an acrylic polymer, and contributes to an increase in the adhesion of a cured product. The hardness of the cured product can be controlled by adjusting the content and molecular weight of the alicyclic skeleton-containing polymer.
The (C) alicyclic skeleton-containing polymer used in the present invention is excellent in compatibility with the (meth) acryloyl-modified diene polymer which is the component (A). Therefore, by being incorporated into the network of the cured product obtained by the curing reaction of the (meth) acryloyl-modified diene polymer which is the (A) component and the (meth) acrylate compound which is the (B) component, (C) Fine dispersion of the alicyclic skeleton-containing polymer can be achieved.
Furthermore, the alicyclic skeleton-containing polymer has a high glass transition point and is excellent in heat resistance. Even when held at high temperature for a long time, decomposition, dehydrogenation and oxidation are less likely to occur, so that the change to optical properties such as transparency and yellowing may be small.

  The alicyclic skeleton-containing polymer is preferably contained in an amount of 1 to 50% by weight, preferably 5 to 40% by mass, and more preferably 15 to 30% by mass of the resin component in the composition. When the content of the alicyclic skeleton-containing polymer in the resin component is high, the cured product tends to be hard, which may result in a decrease in the impact resistance of the cured product. In addition, the content of the α, β-unsaturated carbonyl-modified diene polymer and the (meth) acrylate compound constituting the curing system is relatively reduced, which makes curing difficult. On the other hand, when the content in the resin component is too low, it is difficult to ensure the heat resistance of the cured product, and the adhesion also tends to decrease.

(D) Polybutene and / or Polyisobutylene It is preferable that the composition of the present invention further contains a low molecular weight type polybutene and / or polyisobutylene having a number average molecular weight of 300 to 1,500. Each of polybutene and polyisobutylene may be used alone, or both may be used in combination.

  Polybutene is a copolymer of 1-butene and 2-butene mainly composed of isobutylene, and polyisobutylene is a homopolymer of isobutylene. Those having a wide molecular weight from liquid to solid at room temperature depending on molecular weight are commercially available, but polybutene and polyisobutylene used in the present invention are low molecular weight types having a number average molecular weight of 300 to 1,500.

  Polybutene and polyisobutylene having a number average molecular weight of 300 to 1,500 are liquid at normal temperature and compatible with the cured products of the components (A) and (B), and an alicyclic skeleton-containing polymer which is the component (C) Excellent compatibility with For this reason, in the hardened | cured material obtained, it can be taken in in the network formed of the hardening reaction of (A) component and (B) component with an alicyclic skeleton containing polymer. Furthermore, in preparation of a composition, it can also be used as a synthesis solvent of (C) alicyclic skeleton containing polymer. (C) By using as a synthetic | combination solvent of an alicyclic skeleton containing polymer, the alicyclic skeleton containing polymer solution obtained by synthetic reaction can be utilized for preparation of a composition as it is.

Such polybutene and / or polyisobutylene have a role as a plasticizer. That is, polybutene and / or polyisobutylene have the role of reducing the hardness of the cured product. In this respect, since the alicyclic skeleton-containing polymer has the function of enhancing the hardness of the cured product, the impact resistance and hardness of the cured product can be controlled by adjusting the content ratio with the alicyclic skeleton-containing polymer which is a non-reactive resin. Balance can be adjusted properly.
The content ratio (C: D) of the component (C) to the component (D) is not particularly limited, but is usually in the range of 85:15 to 5:95, and preferably in the range of 60:40 to 20:80. It is selected.

Furthermore, polybutene and polyisobutylene do not have a polar group in the molecular chain, and contribute to lowering the dielectric constant of the composition and the cured product. The content of polybutene and / or polyisobutylene in the composition is 0 to 70% by mass, preferably 10 to 60% by mass, more preferably 20 to 5% by mass in the resin component. It may be set appropriately according to
The total content of the (C) alicyclic skeleton-containing polymer and the (D) polybutene and / or polyisobutylene is preferably 1 to 90% by mass, more preferably 20 to 80% by mass of the total amount of resin components. %, More preferably 50 to 70% by mass.

  Although polybutene and / or polyisobutylene having the above-mentioned molecular weight range exhibit liquid state at normal temperature, those having a pour point of 0 ° C. or less are more preferable.

  A commercial item can also be used as such polybutene, For example, Niseki polybutene LV-7 made by JX Nippon Oil & Energy, Niseki polybutene LV-10, Niseki polybutene LV-25, Niseki polybutene LV -50, Nichiishi polybutene LV-100, Nichiishi polybutene HV-15, Nichiishi polybutene HV-35, Nichiishi polybutene HV-50, Nichiishi polybutene HV-100, Nichiishi polybutene HV-300; Indopol manufactured by ENEOS L-8, Indopol L-14, Indopol H-7, Indopol H-15, Indopol H-25, Indopol H-50, Indopol H-100, Indopol H-300 and the like. Further, commercially available products of polyisobutylene include TPC595, TPC1105 manufactured by Texas Petrochemicals; Glissopal 1000, Glissopal 1300, Glissopal V190, Glissopal V500, Glissopal V640, etc. manufactured by BASF.

(E) Photopolymerization initiator The curable resin composition of the present invention preferably further comprises (E) a photopolymerization initiator in addition to the above components. This makes it possible to cure the composition in a short time by energy beam irradiation.

  As a photoinitiator, the photoinitiator conventionally used in the field | area of an energy ray-curable resin composition can be used. For example, photopolymerization initiators described in paragraphs 0089 and 0090 of JP-A-2013-014718 can be mentioned, and among them, acetophenones, oxy-phenyl-acetic acid 2- [2-oxo-2-phenyl-acetoxy- Ethoxy] ethyl ester, oxy-phenyl-acetic acid 2- [2-hydroxy-ethoxy] ethyl ester, bis (2,4,6-trimethyl benzoyl) -phenyl phosphine oxide, 2,4,6-trimethyl benzoyl- Preferred is diphenyl-phosphine oxide or the like.

  The content of the photopolymerization initiator in the curable resin composition varies depending on the use, but usually, it is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin component in the composition. . When the amount is 0.1 parts by mass or more, the resin composition can be sufficiently cured, and when the amount is 10 parts by mass or less, odor generation and coloring of the cured product can be sufficiently suppressed. More preferably, it is 0.1-5 mass parts, More preferably, it is 0.1-3 mass parts.

(F) Other components The curable resin composition of the present invention is, in addition to the above components, if necessary, other non-reactive resins within the range not to impair the effects of the present invention, particularly colorless transparency. , Fumed silica, and other additives.

  Other non-reactive resins include, for example, phenol resin, modified phenol resin, cyclopentadiene-phenol resin, xylene resin, chroman resin, petroleum resin, terpene resin, terpene phenol resin, rosin ester resin, and water of each of the above resins. Resins having tackifying effect such as adducts; polyether polyols such as polyethylene glycol, polypropylene glycol, ethylene oxide and propylene oxide copolymer; polyolefin resins such as polyethylene, polypropylene, polystyrene, etc .; polymethyl methacrylate, polyacrylic acid etc. (Meth) acrylic polymers having no polymerizable functional group or double bond in the side chain of the polyester; polyester resins such as polyethylene terephthalate; polyamide resins such as nylon 6, 6; hydrogenated type or non-water Type polyisoprene, conjugated diene polymer other than the water-contained polybutadiene and thermoplastic elastomers. Non-reactive resins other than tackifying resins are generally low in heat resistance, and may cause a decrease in adhesion strength after being held at high temperatures for a long time, and coloring. Moreover, even if it is resin which has the tackifying effect, coloring becomes a problem. Therefore, in the resin composition for use such as being held at a high temperature for a long time, the content per 100 parts by mass of the resin composition is preferably 40% by mass or less.

  Fumed silica is a compound having silicon oxide as a main component, and the primary average particle diameter is preferably 50 nm or less. Fumed silica has a silanol group on the particle surface, and there are a hydrophobic type in which a part of the silanol group is modified with an organic group, and a hydrophilic type in which the silanol group remains unmodified. Although any type can be used, it is particularly effective in that the white turbidity of the adhesive under high humidity can be effectively suppressed, and also the temporal separation of polybutene and polyisobutylene from the cured product can be efficiently suppressed even under high temperature. The hydrophilic type is preferably used.

  Furthermore, the thermosetting catalyst, the ultraviolet light absorber, the chain transfer stabilizer, the light stabilizer, the polymerization inhibitor, the antioxidant, the leveling agent, the thickener, as long as the effects of the present invention are not impaired as needed. It may contain a viscosity reducing agent, a thixotropic agent, a defoaming agent, a coloring agent and the like.

  For example, each compound described in paragraphs 0078 to 0082 of JP 2012-162705 A can be used.

  As the above antioxidants, hindered phenols AO-10, AO-20, AO-30, AO-40, AO-50, AO-60, AO-80 (manufactured by Adeka), antage W-300, W-400, W-500 (manufactured by Kawaguchi Chemical Co., Ltd.), tinuvin 765 (manufactured by BASF Corp.) which is a light stabilizer, etc., and the like, and in terms of durability, AO-50, AO-60 It is preferably used.

  The other components as described above are appropriately selected depending on the application of the resin composition, but generally, it is preferably 0 to 40% by mass of the resin composition, more preferably 0 to 20% by mass, particularly preferably It is 0 to 10% by mass.

<Preparation of a curable resin composition>
The curable resin composition of the present invention may be mixed with the above components at a predetermined ratio.
When the resin composition in the resin component contains the total content of the components (A) and (B) and the component (C) (if the component (D) is contained, the total content of the components (C) and (D) It is preferable that ratio (A + B: C + D) with (1) sets it as 10: 90-99: 1, More preferably, it is 20: 80-60: 40, More preferably, it is 50: 50-70: 30.

  Moreover, it is preferable to set it as 85: 15-5: 95, and, as for the content ratio of (C) component and (D) component, More preferably, it is 60: 40-20: 80. When the amount of the alicyclic skeleton-containing polymer (C) is too large, the cured product tends to be hard and the impact resistance tends to be poor, and when the amount of polybutene and / or polyisobutylene (D) is too large, heat resistance, particularly optical properties Heat resistance tends to decrease.

  The preparation method is not particularly limited, but an α, β-unsaturated carbonyl-modified diene polymer solution in which the (meth) acrylate compound which is the component (B) is used as a solvent is prepared, and this solution is used as the component (C) (alicyclic It is preferable to mix with the skeleton-containing polymer). When component (D) is contained, a component solution of component (C) is prepared using polybutene and / or polyisobutylene as component (D) as a solvent, and this is separately prepared .alpha.,. Beta.-unsaturated carbonyl It is preferable to mix with the modified diene polymer solution. The alicyclic skeleton-containing polymer (C) is usually solid at normal temperature, but can be handled as a liquid by the combined use with (D) polybutane and / or polyisobutylene.

  In addition, the (alpha), (beta)-unsaturated carbonyl modified | denatured diene polymer solution which uses a (meth) acrylate type compound as a solvent is prepared by performing an (alpha), (beta)-unsaturated carbonyl modification reaction in a solvent (meth) acrylate type compound. An alicyclic skeleton-containing polymer solution in which polybutene and / or polyisobutylene is used as a solvent can be prepared by conducting a synthesis reaction of an alicyclic skeleton-containing polymer using polybutene and / or polyisobutylene as a solvent.

  Although the compounding order of the photopolymerization initiator and the other additives is not particularly limited, a mixture of components (A), (B), and (C), and optionally contained (D) was prepared. After that, it is preferable to add a photopolymerization initiator and other additives to the mixture.

<Curing method of curable resin composition>
The curable resin composition of the present invention can be applied to a predetermined site by a method such as coating, drop filling, pouring and the like. It may be appropriately selected according to the properties, viscosity and application site of the composition.

  The curable composition of the present invention having the above composition has (A) an α, β-unsaturated carbonyl group ((meth) acryloyl group) of an α, β-unsaturated carbonyl-modified diene polymer and (B) It can be cured by polymerization reaction with (meth) acrylic acid ester. The curing reaction can be initiated by heat, light and various energy beam irradiations. Photocuring is preferred from the viewpoint of curing speed and workability. It is also possible to use curing by heating as well as curing by light irradiation.

As the energy ray, an electron beam, radiation, ultraviolet light and the like can be used, preferably ultraviolet light with a wavelength of 150 to 450 nm. As a light source which emits such a wavelength, a solar light, a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a gallium lamp, a xenon lamp, a flash type xenon lamp, a carbon arc lamp, an LED type UV light source etc. are mentioned, for example Be Irradiation integrated light quantity is preferably 0.1~50J / cm ^2, more preferably 0.2~30J / cm ^2, more preferably in the range of 0.3~3J / cm ^2.

  In the case of heat curing, infrared rays, far infrared rays, hot air, high frequency heating or the like may be used. The heating temperature may be appropriately adjusted according to the decomposition temperature of the thermosetting catalyst, the type of the substrate used, etc., and is not particularly limited, but preferably 50 to 150 ° C., more preferably 50 to 100 ° C. More preferably, it is in the range of 60 to 90 ° C. The heating time may be appropriately adjusted depending on the decomposition temperature of the thermosetting catalyst, the coating thickness, etc., and is not particularly limited, but preferably 1 minute to 12 hours, more preferably 10 minutes to 6 hours, and further Preferably, it is in the range of 10 minutes to 3 hours.

  Furthermore, curing by light irradiation may be used in combination with curing by electron beam irradiation. In this case, an electron beam having an acceleration voltage of preferably 0 to 500 kV, more preferably 20 to 300 kV, and still more preferably 30 to 200 kV may be used. The irradiation dose is preferably in the range of 2 to 500 kGy, more preferably 3 to 300 kGy, and still more preferably 4 to 200 kGy.

  The curable resin composition is cured by initiating the curing reaction as described above. The term "hardening" as used herein means that there is no flowability, and is a state in which the shape can be maintained.

  In addition, although (C) component and (D) component which are non-reactive resin do not participate in hardening reaction, they can be taken in into the network structure of hardened | cured material. The component (C) and the component (D) both have excellent compatibility with the cured product, and therefore, even if polybutene and / or polyisobutylene is liquid at normal temperature, the solvent of the alicyclic skeleton-containing polymer is the component (D). The shape of the cured product is maintained even if it is present as a solution in solution.

<Use of resin composition>
The cured product of the resin composition of the present invention is colorless and transparent, particularly less yellowing and clouding even when stored for a long time at high temperature and humidity, and is excellent in adhesion.

Specifically, the initial yellowness (YI ₀ ) of the cured product obtained by curing the curable resin composition is 1.0 or less (preferably 0.9 or less), and 1000 hours at 105 ° C. The yellowness (YI ₁₀₀₀ ) after exposure under the conditions is 1.9 or less (preferably 1.3 or less), and the increase rate of YI ₁₀₀₀ relative to YI ₀ , that is, the yellowing degree (ΔYI) is 100% or less Preferably it is 80% or less, more preferably 50% or less. The yellowness (YI) is a value measured using, for example, spectro color meter SE2000 (Nippon Denshoku Co., Ltd.).

In addition, the initial haze (H ₀ ) of the cured product obtained by curing the curable resin composition is 0.5% or less (preferably 0.2 or less), and under an environment of 85 ° C. and 85% RH for 1000 hours. Haze (H ₁₀₀₀ ) after exposure to 1% or less (preferably 0.5 or less), and the increase rate (ΔH) of H _{1000 to} H ₀ is 100% or less, preferably 80% or less, more preferably 50% or less.

  Thus, the curable resin composition of the present invention can maintain colorless transparency even when held for a long time under high temperature and high humidity. Therefore, applications not only conventionally known applications such as adhesives and fillers for optical display members, but applications in which the optical characteristics and heat resistance requirements are severe, particularly in specifications which are maintained at high temperatures for a long time, for example It can be suitably used as an on-vehicle optical device, for example, an adhesive of a transparent glass plate and a display of a capacitive touch panel such as a car navigation system or an instrument in a car, a protective sheet or the like, a filler of a gap, and the like.

EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to the descriptions of the following examples.
In the examples, "part" means mass standard unless otherwise noted.

<Measurement and evaluation method>
The measurement and evaluation methods employed in this example are as follows.
(1) Number average molecular weight (Mn)
Using a column TSK-gel SuperHM-H2 column manufactured by Tosoh Corporation and two TSK-gel SuperH2000 columns at a temperature of 40 ° C. and a flow rate of 0.3 mL / min using a mobile phase of tetrahydrofuran as a mobile phase, a gel permeation manufactured by Tosoh Corporation It is a value determined by chromatography (GPC) apparatus HLC-8220GPC and converted to standard polystyrene.

(2) Composition viscosity (mPa · s)
The viscosity of the obtained resin composition was measured using an R / S Rheometer (manufactured by BROOKFIELD, cone plate C50-2) under conditions of a temperature of 25 ° C., and the value at 1 rpm was taken as the measured value.

(3) Curability (J / cm ² )
A conveyor type UV irradiator (irradiation lamp: a lamp manufactured by Fusion, a D bulb, illuminance: 200 mW / cm ^{2) in} a state where the obtained resin composition is sandwiched by a glass plate so that the thickness of the resin composition is 4 mm. A conveyor speed: 1.2 m / min, a UV sensor: UIT-250 (manufactured by Ushio Electric Co., Ltd.) was irradiated with 1 J / cm ² of UV light, and a light irradiation amount at which the hardness value became constant was measured.

(4) Hardness The cured product prepared in the evaluation of the curability is taken out from the glass plate, and this cured product is used as a test piece (width 20 mm × length 20 mm × thickness 4 mm) using a Durometer E hardness meter (ASKAR) The hardness was measured.

(5) Light transmittance (%)
The resin composition was irradiated with ultraviolet light (3 J / cm ² for 30 seconds) in a state where the resin composition was sandwiched by a glass plate (thickness 1 mm) such that the thickness of the resin composition was 0.3 mm. Using a spectrophotometer (type “UV-3100” manufactured by Shimadzu Corp.), the light transmittance at 400 nm of a cured product test piece (50 mm wide × 70 mm long × 0.3 mm thick) sandwiched between glass plates Measured.

(6) relative permittivity ε (100 kHz)
The resin composition was irradiated with ultraviolet light (3 J / cm ² for 30 seconds) in a state where the resin composition was sandwiched by a glass plate (thickness 1 mm) such that the thickness of the resin composition was 0.5 mm. The obtained cured product test piece (50 mm in width × 50 mm in length × 0.5 mm in thickness) is taken out, sandwiched between electrodes (SH2-Z manufactured by Solartron, electrode diameter 10 mm), and capacitance is measured by an impedance analyzer (S1-1260 manufactured by Solartron). The relative permittivity was calculated.

(7) Adhesiveness The resin composition was irradiated with ultraviolet light (3 J / cm ² for 30 seconds) in a state where the resin composition was sandwiched by a glass plate (thickness 1 mm) so that the thickness of the resin composition was 0.3 mm. The following evaluation was performed about the test piece (width 50 mm x length 70 mm x thickness 0.3 mm) of the state pinched | interposed into the glass plate. In addition, also about transparent moisture resistance and yellowing degree, the test piece produced by the said method was used.

(7-1) Adhesion moisture resistance The test piece of the state pinched | interposed into the glass plate was hold | maintained in a constant temperature and humidity chamber (temperature 85 degreeC, humidity 85% RH) for 1000 hours. The state (appearance) of the test piece after heating for 1000 hours was visually confirmed. The case where there was no change was made into "(circle)", when the peeling from a glass plate was recognized, or the case where liquefaction had occurred was "(circle)".
(7-2) Adhesion heat resistance The test piece of the state pinched | interposed into the glass plate was heated in 105 degreeC oven for 1000 hours. It was held for 1000 hours in a constant temperature and humidity chamber (temperature 85 ° C., humidity 85% RH). Thereafter, the test piece was taken out, the state (appearance) of the test piece was visually confirmed, and evaluated on the basis of the same criteria as the adhesion moisture resistance.

(8) Transparent moisture resistance The haze of the test piece (50 mm wide × 70 mm long × 0.3 mm thick) in a state sandwiched between glass plates before and after the test (after holding for 1000 hours) It measured using Meter NDH2000 (Nippon Denshoku Industries Co., Ltd.). From the haze value (H ₀ ) before the test and the haze value (H ₁₀₀₀ ) after holding for 1000 hours, the rate of change in transparency (ΔH (%) = (H ₁₀₀₀ -H ₀ ) / H ₀ × 100) was determined.

(9) Yellowing factor The yellowness (YI) of the test piece (50 mm wide × 70 mm long × 0.3 mm thick) in a state of being sandwiched between glass plates was measured using Spectro Color Meter SE2000 (Nippon Denshoku Kogyo Co., Ltd.) It was measured. The yellowness (YI ₀ ) before heating and the yellowness (YI ₁₀₀₀ ) after heating for 1000 hours in an oven at 105 ° C. are measured, and the yellowing factor (ΔYI (%) = (YI ₁₀₀₀ −YI ₀ ) / YI ₀ × 100) was obtained.

<A: Synthesis of α, β-unsaturated carbonyl modified diene polymer>
(1) Acryloyl modified polybutadiene 1 (multi unit hydrogenated type, 0.5 equivalents)
In a container containing 639.2 g of isobornyl acrylate (manufactured by Nippon Shokubai Co., Ltd.) used as a solvent, 1000 g of NISOSO B GI-3000 (number average molecular weight 3000, iodine number 21 or less) manufactured by Nippon Soda as hydrogenated conjugated diene polymer Was charged. The urethanization catalyst dibutyltin diversatate (0.53 g) and the polymerization inhibitor Adekastab AO-60 (0.53 g) were added and heated to 77 ° C. with stirring under bubbling. Then, 28.32 g (corresponding to 0.5 equivalent to the hydroxyl group contained in GI-3000) of isophorone diisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., product number Desmodu I, the same applies hereinafter) as a compound for connection is added. The mixture was reacted at 80 ° C. for 120 minutes to multimerize. Subsequently, as an α, β-unsaturated compound, 35.97 g (corresponding to 0.5 equivalent to a hydroxyl group contained in GI-3000) of 2-acryloyloxyethyl isocyanate (manufactured by Showa Denko, product number: Karenz AOI) And allowed to react at 80 ° C. for 120 minutes to obtain an acryloyl modified product 1 (Mn = 8000) of multi-unit type hydrogenated polybutadiene (0.5 equivalent).

(2) Acryloyl modified polybutadiene 2 (multi-unit non-hydrogenated type, 0.5 equivalents)
Acryloyl-modified polybutadiene except that non-hydrogenated conjugated diene-based polymer polyol G-3000 manufactured by Nippon Soda Co., Ltd. is used as the hydrogenated conjugated diene-based polymer polyol in place of NISOSOB GI-3000 manufactured by Nippon Soda Co., Ltd. The synthesis was carried out in the same manner as 1 to obtain acryloyl modified polybutadiene 2 (0.5 equivalent) (Mn = 8000).

<Synthesis of alicyclic skeleton-containing polymer>
(1) Polyisobornyl acrylate 7000 (PIBA 7000)
(1-1) PIBA 7000-1
44 g of isobornyl acrylate (manufactured by Nippon Shokuhin Co., Ltd.) was charged in a container containing 105 g of polybutene (NX Nippon Polysilicon HV-15 (Mw = 630) manufactured by JX Nippon Oil & Energy Corporation as a solvent, and stirred under nitrogen bubbling While heating to 77 ° C. 0.6 g of 2,2′-azobis (3,4-dimethylvaleronitrile) (hereinafter abbreviated as “ABNV”) previously diluted with 16 g of isobornyl acrylate and n-dodecyl mercaptan 1. 2 g was charged and reacted for 150 minutes at 85 ° C. The number average molecular weight of the obtained polyisobornyl acrylate was 7000. The polyisobornyl acrylate thus obtained is referred to as “PIBA 7000-1”. The polyisobornyl acrylate (PIBA 7000-1) solution was prepared as it was according to composition No. 1. It was subjected to.

(1-2) PIBA 7000-2
In a container filled with 105 g of toluene as a solvent, 44 g of isobornyl acrylate (manufactured by Nippon Shokubai Co., Ltd.) was charged and heated to 77 ° C. with stirring under nitrogen bubbling. 0.6 g of ABN V and 1.2 g of n-dodecyl mercaptan previously diluted with 16 g of isobornyl acrylate were charged, and reacted at 85 ° C. for 150 minutes. The number average molecular weight of the obtained polyisobornyl acrylate was 7,000. The polyisobornyl acrylate thus obtained is referred to as "PIBA7000-2".
To this solution of polyisobornyl acrylate (PIBA 7000-2), predetermined amounts of isobornyl acrylate and polybutene (HV-15) were added according to the composition to be prepared, and the toluene was depressurized and degassed. The mixture was subjected to the preparation of 4, 6

(2) Polyisobornyl acrylate 50000 (PIBA 50000)
In a container containing 105 g of polybutene (HV-15) as a solvent, 44 g of isobornyl acrylate (manufactured by Nippon Shokubai Co., Ltd.) was charged and heated to 77 ° C. with stirring under nitrogen bubbling. 0.1 g of ABNV previously diluted with 16 g of isobornyl acrylate was charged, and reacted at 85 ° C. for 150 minutes. The number average molecular weight of the obtained polyisobornyl acrylate was 50000.
The obtained polyisobornyl acrylate (PIBA 50000) solution was subjected to composition preparation as a polybutene mixture.

(3) Polyisobornyl acrylate 100000 (PIBA 100000)
In a container filled with 75 g of toluene as a solvent, 44 g of isobornyl acrylate (manufactured by Nippon Shokubai Co., Ltd.) was charged and heated to 77 ° C. with stirring under nitrogen bubbling. 0.1 g of ABNV previously diluted with 16 g of isobornyl acrylate was charged, and reacted at 85 ° C. for 150 minutes. The number average molecular weight of the obtained polyisobornyl acrylate was 100,000. To the resulting solution of polyisobornyl acrylate (PIBA 100000), predetermined amounts of isobornyl acrylate and polybutene (HV-15) are added according to the composition to be prepared, and toluene is degassed under reduced pressure to prepare a composition. Provided.

(4) Polyisobornyl methacrylate 7500 (PIBM 7500)
In a container containing 175 g of polybutene (HV-15) as a solvent, 75 g of isobornyl methacrylate (manufactured by Nippon Shokubai Co., Ltd.) was charged and heated to 77 ° C. with stirring under nitrogen bubbling. 1.0 g of ABNV and 2.0 g of n-dodecyl mercaptan diluted in advance with 25 g of isobornyl methacrylate were charged, and reacted at 85 ° C. for 150 minutes. The number average molecular weight of the obtained polyisobornyl methacrylate was 7500.
The resulting polyisobornyl methacrylate (PIBM 7500) solution was subjected to composition preparation as a polybutene mixture.

(5) Polydicyclopentanyl Acrylate This was synthesized in the same manner as (1) polyisobornyl acrylate except that dicyclopentanyl acrylate (manufactured by Hitachi Chemical Co., Ltd.) was used instead of isobornyl acrylate. The number average molecular weight of the obtained polydicyclopentanyl acrylate was 8,000.
The resulting polydicyclopentanyl acrylate solution was subjected to composition preparation as a polybutene mixture.

<Other non-reactive resin: polyisodecyl acrylate>
The synthesis was performed in the same manner as (1) polyisobornyl acrylate except that isodecyl acrylate (manufactured by Sartomer) was used instead of isobornyl acrylate. The number average molecular weight of the obtained polyisodecyl acrylate was 6,800.
The obtained polyisodecyl acrylate solution was used as it was for composition preparation as a polybutene mixture.

<Curable resin composition No. Preparation of 1-9, 11, 12>
Acryloyl modified diene polymer solution (solvent: isobornyl acrylate) synthesized above; alicyclic skeleton-containing polymer solution (solvent: polybutene) or polyisodecyl acrylate solution (solvent: polybutene) and hydroxypropyl acrylate (Tg-7 C., manufactured by Nippon Shokubai Co., Ltd., were mixed so as to have the proportions shown in Table 1. Furthermore, 1 part by mass of Irgacure TPO (monoacyl phosphine oxide) (manufactured by BASF) as a photopolymerization initiator (E) is added and mixed, and dispersed and stirred by a homomixer (manufactured by Primix) to obtain resin composition No. 1; 1-9, 11 and 12 were prepared. From the relationship between the content ratio of the alicyclic skeleton-containing polymer and the polybutene in the solution of the alicyclic skeleton-containing polymer, composition No. 1 is prepared. For No. 1, using a polymer solution of PIBA 7000-1 (solvent: polybutene) PIBA7000-2 was used for 2, 4.
The viscosity of the obtained resin composition was measured. Moreover, when the curability of the resin composition was measured by the said evaluation method, all were ² J / cm < ² >.

  The hardness, the light transmittance, the relative dielectric constant, the adhesion, the transparent moisture resistance, and the degree of yellowing of the resin composition were measured based on the measurement and evaluation method. The measurement results are shown in Table 1. In addition, about No. 8, since viscosity was too high and there was a problem in handleability, evaluation of hardened | cured material was not performed.

<Curable resin composition No. Preparation of 10>
Acryloyl modified diene polymer solution (solvent: isobornyl acrylate) synthesized above; polybutene (HV-15) as non-reactive resin; KE-311 (Arakawa Chemical Industries, Ltd.) hydrogenated rosin ester as tackifier A trade name) and hydroxypropyl acrylate (Tg-7 ° C, manufactured by Nippon Shokubai Co., Ltd.) were blended in the proportions shown in Table 1. Furthermore, 1 part by mass of Irgacure TPO (monoacyl phosphine oxide) (manufactured by BASF) as a photopolymerization initiator (E) is added, and the mixture is dispersed and stirred by a homomixer (manufactured by PRIMIX Corporation). 10 was prepared.
The viscosity of the obtained resin composition was measured. Moreover, when the curability of the resin composition was measured by the said evaluation method, all were ² J / cm < ² >.
The hardness, the light transmittance, the relative dielectric constant, the adhesion, the transparent moisture resistance, and the degree of yellowing of the resin composition were measured based on the measurement and evaluation method. The measurement results are shown in Table 1.

  As can be seen from Table 1, when no alicyclic skeleton-containing polymer was contained as the non-reactive resin (Nos. 9, 12), the adhesion was inferior.

No. No. 10 is a composition which does not contain an alicyclic skeleton-containing polymer as a non-reactive resin, but since it contains a rosin ester which is a tackifier, adhesion can be secured. However, the degree of yellowing (ΔYI) when held at high temperature for a long time exceeded 100%, and the requirement for achromaticity was at an unsatisfying level in the strict specification.
On the other hand, no. As to No. 9, the reason for the low yellowing factor (ΔYI) when held at high temperature for a long time is considered to be that it does not contain a non-reactive resin to be a tackifying resin.

  No. 12 is a case where instead of the alicyclic skeleton-containing polymer, a polymer of long chain alkyl acrylate having no alicyclic skeleton is contained as a non-reactive resin. The adhesion was poor, and the transparency change rate (ΔH) and yellowing rate (ΔYI) were large, and heat resistance and moisture resistance were insufficient as optical applications.

  On the other hand, composition No. 1 in which an alicyclic skeleton-containing polymer is contained in a curing system consisting of an acryloyl-modified diene polymer and an acrylate compound. All of the samples 1 to 7 were able to maintain the initial colorless transparency even in the case of adhesion and long-term holding under high temperature and high humidity. Therefore, it can be suitably used for optical devices such as displays, etc. for which the requirement for colorless transparency is strict, and particularly for in-vehicle optical devices which are kept at high temperature for a long time.

  No. From the comparison of 1, 2, 7 and 8, it is understood that the hardness of the cured product tends to be higher as the molecular weight is higher for the alicyclic skeleton-containing polymer. And when the molecular weight of the alicyclic skeleton-containing polymer is 100,000 (No. 8), the viscosity of the composition becomes too high, making it difficult to prepare a transparent composition.

  Also, no. From the comparison of 1 and 4, it can be seen that even when the molecular weight of the alicyclic skeleton-containing polymer is the same, the hardness of the cured product tends to increase as the content increases. Since the density of the network can be adjusted by changing the mixing ratio of the polymer and the acrylate compound, it can be seen that the hardness of the cured product can be adjusted by appropriately adjusting the contents thereof (No. 1, 4 and No. .6 comparison).

  No. 11 is a case containing an alicyclic skeleton-containing polymer, but the yellowing degree was large when it was kept for a long time under high temperature. This is considered to be because the double bond derived from the conjugated diene-based polymer causes yellowing because the acryloyl-modified non-hydrogenated polybutadiene is used as the acryloyl-modified diene-based polymer. Therefore, in applications requiring high degree of colorless transparency, it is necessary to use an α, β-unsaturated carbonyl modified product of a hydrogenated conjugated diene polymer as the component (A).

  Since the curable resin composition of the present invention can maintain colorless transparency and maintain excellent adhesion even when exposed to high temperature and high humidity for a long time, an optical device used at high temperature and high humidity In particular, it can be suitably used as a filler or an adhesive used for a vehicle-mounted display or the like.

Claims (10)

(A) a conjugated diene polymer units selected from hydrogenated polybutadiene and hydrogenated polyisoprene down or Ranaru group comprises one or more, and the main chain and / or side chains alpha, beta-unsaturated carbonyl modified Polymers (hereinafter referred to as “α, β-unsaturated carbonyl-modified diene polymers”);
(B) (meth) acrylate compounds ;
(C) an alicyclic skeleton-containing polymer having a number average molecular weight of 5,000 to 80,000 having a repeating unit of the following formula (11) ;
(D) A curable resin composition containing polybutene and / or polyisobutylene having a number average molecular weight of 300 to 1,500 .

In the formula (11), Rc is an alicyclic skeleton-containing group, and R ¹⁰ and R ¹¹ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an allyloxyalkyl group having 1 to 6 carbon atoms ). The curable resin composition according to claim 1, wherein the alicyclic skeleton contained in Rc in the formula (11) is a polycyclic system. Wherein (C) alicyclic skeleton glass transition temperature containing polymer (Tg) of the curable resin composition according to claim 1 or 2 is 50 ° C. or higher. The content mass ratio (C: D) of said (C) alicyclic skeleton containing polymer and said (D) polybutene and / or polyisobutylene is 85: 15-5: 95, The any one of Claims 1-3 Curable resin composition as described. The total content of the (C) alicyclic skeleton-containing polymer and the (D) polybutene and / or polyisobutylene is 1 to 90% by mass with respect to the total amount of resin components. Curable resin composition. Wherein (A) alpha, beta-total content of unsaturated carbonyl modified diene polymer and (B) (meth) acrylate compound is any one of claims 1-5 which is 10 to 99% by weight of the resin component total amount The curable resin composition according to item 1. The initial yellowness (YI ₀ ) of the cured product obtained by curing the curable resin composition is 1.0 or less, and the yellowness (YI ₁₀₀₀ ) after exposure under the condition of 105 ° C. for 1000 hours is The curable resin composition according to any one of claims 1 to 6 , which is 1.9 or less. The initial haze (H ₀ ) of the cured product obtained by curing the curable resin composition is 0.5% or less, and the haze (H ₁₀₀₀ ) after exposure to an environment at 85 ° C. and 85% RH for 1000 hours is The curable resin composition according to any one of claims 1 to 7 , which is 2.0% or less. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 8 by energy ray irradiation. The image display apparatus which has a hardened | cured material of Claim 9 .