JP2015007191A - Energy ray-curable resin composition using unsaturated carbonyl modified conjugated diene-based hydrogenated polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy ray-curable resin composition having excellent thixotropic properties capable of being formed into a cured product having a low dielectric constant and excellent transparency and durability.SOLUTION: There is provided an energy ray-curable resin composition which comprises: (A) a conjugated diene-based polymer having two or more α,β-unsaturated carbonyl groups and an iodine value of 100 or less; and (B) a photopolymerization initiator, wherein (A) the conjugated diene-based polymer preferably contains a multimer-type conjugated diene-based polymer in which polyols (a-1) having a number average molecular weight of 500 to 40000 are linked via one kind of bond selected from the group consisting of an urethane bond, an ester bond and an ether bond, and molecular terminals of the multimer-type polymer are modified with α,β-unsaturated carbonyls, and further contains a thixotropy-imparting agent.

Description

  The present invention relates to an energy beam curable type using a polymer (unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer) obtained by modifying a molecular chain of a conjugated diene-based polymer that is at least partially hydrogenated with α, β-unsaturated carbonyl. More specifically, the resin composition relates to an energy beam curable resin composition that is excellent in thixotropy, can provide a cured product having low dielectric constant, transparency, and durability.

  An energy ray curable resin composition using a polymer (meth) acrylate having a polymerizable functional group such as an acryloyl group or a methacryloyl group (collectively referred to as “(meth) acryloyl group” when these are not particularly distinguished), It is possible to precisely control the curing reaction and to obtain cured products with excellent electrical properties such as heat resistance, chemical resistance, insulation, and adhesiveness. It is used as an adhesive or a filler that fills the gaps between these members.

  In particular, liquid crystal display devices used for mobile phones, liquid crystal televisions, personal computer displays, etc., and image display devices such as touch panels, the touch panel touch member (window) and transparent between the transparent image display unit and the protection unit. Since it is necessary to use a transparent resin adhesive with high visible light transmittance in the gap between the transparent members, such as between the electrode layers, research and development of materials with excellent transparency and durability in addition to the above characteristics It has been.

  Specifically, a resin composition containing polyisoprene acrylate and hydroxybutyl acrylate (for example, JP 2009-186963 A (Patent Document 1)), a polyether (meth) acrylate (for example, JP 2012-162705 A). Gazette (Patent Document 2)), urethane acrylate polymer (for example, JP 2013-3952 A (Patent Document 3)), and conjugated diene polymer having a (meth) acryloyl group (for example, JP 2013-23690 ( Patent Literature 4)) and the like have been proposed.

  Patent Document 1 shows that a cured product of an energy ray-curable resin composition using polyisoprene acrylate and hydroxybutyl acrylate has excellent adhesion and a small curing shrinkage rate. Patent Document 2 shows that a cured product of an energy ray curable resin composition using polyether (meth) acrylate is colorless and transparent and excellent in durability such as heat resistance and light resistance.

  By the way, in an electronic terminal or a mobile phone image display device using a capacitive touch panel that has been rapidly spreading in recent years, as described in Patent Document 3, between a touch panel member and a transparent electrode layer. It has become known that the dielectric constant of the filler to be filled affects the sensitivity of the touch panel. In Patent Document 3, in order to improve the sensitivity of the capacitive touch panel, the dielectric constant of the first transparent adhesive layer interposed between the window and the upper electrode layer in the touch panel is the second interposed between the two electrode layers. It has been proposed to make it larger than the dielectric constant of the transparent adhesive layer. Here, in the ultraviolet curable resin composition adhesive mainly composed of a polymer modified with acryloyl group or methacryloyl group at the end of urethane acrylate polymer, the type and amount of diluent are changed to change the dielectric of the cured product. The rate is changed to satisfy the above relationship.

  Patent Document 4 shows that a photosensitive resin composition containing a conjugated diene polymer having a specific molecular weight distribution has excellent adhesiveness and good impact resistance.

JP 2009-186963 A JP 2012-162705 A JP 2013-3952 A JP 2013-23690 A

  As described above, the energy ray curable resin composition used for adhesion of optical equipment such as an image display device is excellent in transparency, durability such as heat resistance, light resistance, moisture resistance, and curing shrinkage. Is required to be small. Furthermore, it is required to have electrical characteristics, particularly a low dielectric constant, for an adhesive having an optical member on which a transparent electrode layer such as a touch panel is formed as an adherend.

  However, Patent Documents 1 and 2 do not describe or evaluate the dielectric constant. Moreover, although patent document 3 is examining the dielectric constant of hardened | cured material, the sensitivity of a touch panel is improved by adjusting the combination (relationship of two types of adhesives) of two types of adhesives used for an apparatus. There is no description about the relationship between the polymer (meth) acrylate and the dielectric constant.

  The present invention has been made in view of such circumstances, and the object of the present invention is suitable as an adhesive between optical members and a filler between optical members in an image display device including a capacitive touch panel. It is an object to provide an energy beam curable resin composition, that is, an energy beam curable resin composition having a low dielectric constant, high transparency, and excellent durability.

  As a result of various studies on α, β unsaturated carbonyl-modified polymers that can achieve a low dielectric constant, the present inventors have found that a (meth) acrylate of a conjugated diene polymer can provide a cured product having a low dielectric constant. . However, α, β-unsaturated carbonyl-modified conjugated diene-based polymers cause a decrease in transparency under high humidity, and further improvements are required as adhesives and fillers used in image display devices that require severe transparency. Met. There is also room for improvement in durability such as heat resistance, light resistance, and moisture resistance. The present inventors have further studied an energy beam curable resin composition capable of providing a cured product having a low dielectric constant, high transparency, and excellent durability, and reached the present invention. did.

  That is, the energy ray curable resin composition of the present invention includes (A) a conjugated diene polymer having two or more α, β-unsaturated carbonyl groups and an iodine value of 100 or less; (B) photopolymerization. Contains an initiator.

  In the (A) conjugated diene polymer, a polyol (a-1) having a number average molecular weight of 500 to 40,000 is linked through one kind of bond selected from the group consisting of a urethane bond, an ester bond, and an ether bond. It is a multimeric polymer, and it is preferable that a molecular chain terminal of the multimeric polymer contains a multimeric conjugated diene polymer in which α, β unsaturated carbonyl modification is performed.

  Furthermore, the multimeric conjugated diene polymer is at least one selected from the group consisting of a polyol (a-1) having two or more hydroxyl groups at the terminal, an isocyanate group, a carboxyl group, a carbonyl halide group, an epoxy ring, and a hydroxyl group. It is preferable that the molecular chain terminal of the reaction product (hereinafter referred to as “multimeric polyol”) with the linking compound L having two or more species is modified with α, β-unsaturated carbonyl.

  The (A) conjugated diene polymer preferably has a butadiene skeleton.

  Furthermore, it is preferable to contain a (C) hydrophilic group-containing (meth) acrylate compound, and the content of the hydrophilic group-containing (meth) acrylate compound (C) is 1 to 10% by mass of the entire resin composition. Preferably there is.

  The energy beam curable resin composition of the present invention preferably further contains (D) a thixotropic agent.

  The present invention also includes a cured product obtained by curing the energy beam curable resin composition of the present invention by energy beam irradiation (preferably ultraviolet irradiation), and a display device having the cured product.

  The energy beam curable resin composition of the present invention is excellent in thixotropy, and can provide a cured product having a low dielectric constant, transparency, moisture resistance, and durability.

The description of the constituent requirements described below is an example (representative example) of an embodiment of the present invention, and is not limited to these contents.
<Energy beam curable resin composition>
The energy beam curable resin composition of the present invention comprises (A) a conjugated diene polymer having two or more α, β-unsaturated carbonyl groups and an iodine value of 100 or less (hereinafter referred to as “α, β- (It may be referred to as “unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer”) and (B) a photopolymerization initiator.

Hereinafter, compounds obtained by hydrogenating a conjugated diene compound as a raw material will be described as conjugated diene-based hydrogenated compounds. The present invention uses a compound having an iodine value of 100 or less without being hydrogenated as a raw material. It may be used.
(A) α, β-unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer The “α, β-unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer” as component A is an α, β such as a (meth) acryloyl group. -It is preferably a polymer having an iodine value of 100 or less by hydrogenation of at least a part of the conjugated diene compound whose main chain and / or side chain is modified with an unsaturated carbonyl group. Usually, it is synthesized by a reaction between a conjugated diene-based hydrogenated polymer polyol (a-1) and an α, β-unsaturated carbonyl compound (a-2) having a functional group capable of reacting with a hydroxyl group.
[Conjugated diene hydrogenated polymer polyol (a-1)]
The conjugated diene hydrogenated polymer polyol (a-1) is a conjugated diene polymer obtained by 1,2-addition polymerization and / or 1,4-addition polymerization of a conjugated diene compound and contains two or more hydroxyl groups. Examples thereof include hydrogenated polyols.

  Examples of the conjugated diene compound include aliphatic conjugated diene compounds such as butadiene, isoprene, piperelin, and dimethylbutadiene; 1-phenylbutadiene, 2-phenylbutadiene, 1,1-diphenylbutadiene, 1,2-diphenylbutadiene, 2,3 -Aromatic-containing conjugated diene compounds such as diphenylbutadiene may be mentioned, and these may be used alone or in combination of two or more.

  Examples of conjugated diene-based hydrogenated polymer polyols include, for example, a structure of a hydrogenated product (formula (1b)) obtained by hydrogenating a polyol (formula (1a)) having hydroxyl groups bonded to both ends of polybutadiene and polyisoprene. A polymer is mentioned, and an iodine value will be 100 or less because at least one part of Formula (1a) is hydrogenated. In the formula, n is an integer of 10 to 600.

  The number average molecular weight of such a conjugated diene-based hydrogenated polymer polyol is usually about 500 to 40,000 although it varies depending on the type of conjugated diene compound as a constituent monomer and the degree of polymerization.

（ただし、式中R₁は水素またはメチル基を表す。）

本発明で用いることができる共役ジエン系水添ポリマーポリオールは、共役ジエンの１，２−付加物及び／又は１，４−付加物の繰り返し単位からなる高分子鎖の水添物である共役ジエン系水添ポリマーポリオール（単体型共役ジエン系水添ポリマーポリオール）だけでなく、下記式（２）であらわされるように、共役ジエン系水添ポリマーが、連結部を介して連結された多量体型共役ジエン系水添ポリマーポリオール（ヨウ素価が１００以下）、さらには、これらの混合物を用いることができる。

(In the formula, R ₁ represents hydrogen or a methyl group.)

The conjugated diene-based hydrogenated polymer polyol that can be used in the present invention is a conjugated diene that is a hydrogenated polymer chain composed of a 1,2-adduct and / or 1,4-adduct repeating unit of a conjugated diene. As shown by the following formula (2), not only a hydrogenated polymer polyol (single conjugated diene hydrogenated polymer polyol) but also a multimeric conjugate in which a conjugated diene hydrogenated polymer is linked via a linking part. Diene-based hydrogenated polymer polyols (iodine value of 100 or less) and mixtures thereof can be used.

式（２）中、共役ジエン系水添ポリマー部は、共役ジエン系化合物の１，２−付加物又は１，４−付加物を繰り返し単位とする高分子鎖の少なくとも一部が水素化されている水添物（ヨウ素価が１００以下）であり、単体型共役ジエン系水添ポリマーポリオールと同様、通常、数平均分子量５００〜８００００の高分子鎖である。また、式（２）中、連結部は、ウレタン結合、エステル結合、及びエーテル結合からなる群より選ばれる結合である。このように、数平均分子量５００〜４００００の共役ジエン系水添ポリマーが連結部を介して多量体化することにより、共役ジエン系水添ポリマーポリオール及び得られる不飽和カルボニル変性共役ジエン系水添ポリマーの分子量を増大させることができる。

In the formula (2), the conjugated diene-based hydrogenated polymer portion is obtained by hydrogenating at least a part of a polymer chain having a 1,2-adduct or 1,4-adduct of a conjugated diene compound as a repeating unit. This is a hydrogenated product (iodine value of 100 or less), and is usually a polymer chain having a number average molecular weight of 500 to 80,000, similar to the simple conjugated diene-based hydrogenated polymer polyol. Moreover, in Formula (2), a connection part is a coupling | bonding chosen from the group which consists of a urethane bond, an ester bond, and an ether bond. Thus, the conjugated diene-based hydrogenated polymer having a number average molecular weight of 500 to 40,000 is polymerized via the linking portion, so that the conjugated diene-based hydrogenated polymer polyol and the resulting unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer are obtained. The molecular weight of can be increased.

  Such a multimeric conjugated diene hydrogenated polymer polyol is usually at least one selected from the group consisting of a conjugated diene hydrogenated polymer polyol and an isocyanate group, a carboxyl group, a carbonyl halide group, an epoxy ring, and a hydroxyl group. It can be obtained by reacting with a linking compound L having 2 or more.

  Hereinafter, when simply referred to as “conjugated diene-based hydrogenated polymer polyol”, a conjugated diene-based hydrogenated polymer including a simple conjugated diene-based hydrogenated polymer polyol, a multimeric conjugated diene-based hydrogenated polymer polyol, and a mixture thereof. In general, polyols are generically referred to as “single conjugated diene hydrogenated polymer polyol” or “multimeric conjugated diene hydrogenated polymer polyol”.

  In the formulas (1) and (2), the conjugated diene-based hydrogenated polymer portion is hydrogen-saturated and part or all of the double bonds contained in the repeating unit are hydrogen-saturated and has an iodine value of 100 or less. . That is, the hydrogenation may be either complete hydrogenation or partial hydrogenation. The double bond in the conjugated diene (hydrogenated) polymer part causes a decrease in light transmittance and a decrease in durability against heat, light, and humidity. It is preferable to reduce the double bond of the diene (hydrogenated) polymer part and to set the iodine value to 100 or less. For example, the hydroxyl group-containing hydrogenated polybutadiene can be produced by reducing the double bond of the hydroxyl group-containing polybutadiene with hydrogen. The hydrogenation rate of the hydroxyl group-containing hydrogenated polybutadiene is 80% or more of the total double bonds, preferably 90% or more, more preferably 99% or more, and further preferably 99.5%. The remaining double bond can be subjected to quantitative analysis (referred to as “iodine value”) by addition reaction of iodine. In the present invention, the iodine value is 100 or less, preferably 50 or less, more preferably 25 or less, and further preferably 15 or less. The iodine value can be measured according to JISK0070.

Here, as a method of hydrogenation, it can be performed by a known hydrogenation reaction as described in, for example, Japanese Patent Publication No. 42-25304 and Japanese Patent Application Laid-Open No. 2011-195823. For example, using a reaction product of a metal hydrocarbyl compound such as triisobutylaluminum and an organic compound of iron, cobalt, or nickel as a catalyst, hydrogenation is performed so that the diene polymer and hydrogen can be contacted in the presence of the catalyst. This can be done.
[Multimeric conjugated diene-based hydrogenated polymer polyol]
The multimeric conjugated diene-based hydrogenated polymer polyol is obtained by linking a single-type conjugated diene-based hydrogenated polymer polyol through one type of bond selected from the group consisting of a urethane bond, an ester bond, and an ether bond. Say. The multimer-type conjugated diene-based hydrogenated polymer polyol includes at least one selected from the group consisting of the above-mentioned simple-type conjugated diene-based hydrogenated polymer polyol and an isocyanate group, a carboxyl group, a carbonyl halide group, an epoxy ring, and a hydroxyl group. It is obtained by reacting with at least one linking compound L.
[Linking Compound L]
The linking compound L is a compound having two or more functional groups capable of reacting with the hydroxyl group of the polyol (a-1). For example, a bifunctional compound represented by the following formula (3a) and a trifunctional compound represented by (3b) Compound, and a tetrafunctional compound represented by (3c).

上記式（３ａ）（３ｂ）（３ｃ）中、Ａは水酸基と反応する官能基であり、Ｒ，Ｒ’，Ｒ″は有機基である。

In the above formulas (3a), (3b), and (3c), A is a functional group that reacts with a hydroxyl group, and R, R ′, and R ″ are organic groups.

Specific examples of the functional group A include (i) an isocyanate group, (ii) a carboxyl group, (iii) a halogenated carbonyl group, (iv) an epoxy ring, and (v) a hydroxyl group. The organic groups R, R ′, and R ″ may be any of aliphatic, aromatic, and alicyclic groups having the above functional groups and 2, 3, and 4 free bonds, From the viewpoints of reactivity and compatibility with the component (a-1), an aliphatic or alicyclic group having 2 to 18 carbon atoms, preferably 3 to 15 carbon atoms, particularly preferably 8 to 12 carbon atoms is 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, and preferably a diisocyanate.

  Examples of the diisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate; lysine diisocyanate, tetramethylxylylene diisocyanate, trimethylhexane diisocyanate, or a derivative of tetramethylhexane diisocyanate. Aliphatic diisocyanates such as 1,4-, 1,3- or 1,2-diisocyanatocyclohexane, 4,4′- or 2,4′-di (isocyanatocyclohexyl) methane, 1-isocyanato-3, 3,5-trimethyl-5- (isocyanatomethyl) cyclohexane (isophorone diisocyanate), 1,3- or 1,4-bis ( Socyanatomethyl) cyclohexane, or cycloaliphatic diisocyanates such as 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′-diisocyanate.

  Triisocyanates such as tris (phenyl isocyanate) thiophosphate and tetraisocyanates such as 1,3,5,7-adamantanetetrayltetraisocyanate may be used.

  The isocyanate group-containing linking compound as described above reacts with the hydroxyl group of the polyol (a-1) to form a urethane bond. Therefore, the polyol is dimerized, trimerized, or tetramerized according to the number of functional groups, with the urethane bond as the linking moiety. Even when a bifunctional linking compound is used, the terminal OH group of the dimerized polyol may further react with the linking compound to trimerize.

The reaction between the isocyanate group-containing linking compound and the polyol (a-1) is carried out under conditions that do not cause gelation. Usually, conditions that do not cause gelation can be selected as appropriate depending on the type of reaction catalyst, adjustment of the charge amount ratio of polyol and linking compound L, adjustment of reaction temperature, charge rate (dropping rate), and the like.
(Ii) Carboxyl group-containing linking compound As the linking compound having two or more carboxyl groups, dicarboxylic acids, tricarboxylic acids, polycarboxylic acids, or anhydrides thereof can be used, and these are saturated aliphatic carboxylic acids. Acids, unsaturated carboxylic acids, substituted carboxylic acids in which hydrogen atoms other than carboxyl groups are substituted with halogens, hydroxyl groups, carbonyl groups, aromatic carboxylic acids, etc., 2 to 18 carbon atoms, preferably 3 to 15 carbon atoms, more preferably 8-12 saturated carboxylic acids.

Specific examples of carboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, citric acid, and propanetricarboxylic acid. Unsaturated carboxylic acids such as acids, fumaric acid, maleic anhydride, citraconic acid and mesaconic acid; aromatic carboxylic acids such as phthalic acid and the like (iii) halogenated carbonyl group-containing linking compounds What is a carbonyl halide group? , -COXhal (Xhal represents a halogen atom). Examples of the linking compound having two or more halogenated carbonyl groups include pyridine 2,6-dicarboxylic acid dichloride.

  The carboxyl group-containing linking compound and the carbonyl halide-containing linking compound as described above react with the hydroxyl group of the polyol (a-1) to form an ester bond. Accordingly, a conjugated diene polymer polyol in which the polyol is dimerized, trimerized, or tetramerized according to the number of functional groups with an ester bond as a linking moiety is obtained. Similar to the case of the isocyanate group-containing linking compound, even when the bifunctional linking compound is used, the terminal OH group of the dimerized polyol further reacts with the linking compound to trimerize. There is also a case.

The reaction of the carboxyl group-containing linking compound and the halogenated carbonyl group-containing linking compound with the polyol (a-1) is carried out under conditions that do not cause gelation due to rapid multimerization.
(Iv) Epoxy group-containing linking compound The epoxy group-containing linking compound has two or more three-membered ring structures (epoxy group, oxirane group, glycidyl group, etc.) composed of carbon and oxygen atoms as functional groups that react with hydroxyl groups. An epoxy resin obtained by reacting, for example, bisphenol A, bisphenol F or a hydrogenated product thereof with epichlorohydrin, having 2 to 18 carbon atoms, preferably 3 to 15 carbon atoms, more preferably 8 to Twelve epoxy resins are preferably used. Specifically, bisphenol A diglycidyl ether, diglycidyl ether, or the like can be used.

  Such an epoxy group-containing linking compound reacts with the hydroxyl group of the polyol (a-1) to open the epoxy ring and form an ether bond. Therefore, a polyether polyol is dimerized, trimerized, or tetramerized with an ether bond as a linking moiety, depending on the number of functional groups and reaction conditions. It is done.

The reaction between the epoxy group-containing linking compound and the conjugated diene hydrogenated polymer polyol (a-1) is carried out under conditions that do not cause gelation due to rapid multimerization.
(V) Hydroxyl-containing linking compound A hydroxyl-containing linking compound is an organic compound containing two or more hydroxyl groups (—OH) as a functional group, such as diols such as ethylene glycol, trimethylene glycol, tetramethylene glycol, pinacol, Examples include triols such as glycerin and erythritol; lower alkyl polyols having 2 to 8 carbon atoms such as tetraols such as sorbitol. Among these, diols are preferable.

The hydroxyl group-containing linking compound as described above reacts with the hydroxyl group of the polyol (a-1) (usually a dehydration condensation reaction) to form an ether bond. Therefore, a conjugated diene-based hydrogenated polymer polyol in which the polyol is dimerized, trimerized, or tetramerized according to the number of functional groups with an ether bond as a linking moiety is obtained. Similar to the case of the isocyanate group-containing linking compound, even when the bifunctional linking compound is used, the terminal OH group of the dimerized conjugated diene hydrogenated polymer polyol further reacts with the linking compound. Then, it may be trimerized.
(Vi) Other linking compounds The linking compounds that can be used in the present invention include two functional groups of the same type in the compound, such as the linking compounds shown in (i) to (v) above. It is not limited to the compound containing above, You may use the compound which contains two or more different types of functional groups, for example, the oxyacid etc. which have a hydroxyl group and a carboxyl group.

  As described above, when the bifunctional linking compound represented by the above formula (3a) is used as the linking compound, the dimerized conjugated diene-based hydrogenated polymer represented by the following formula (4a) A polyol is obtained. In the formula, Z is a bond formed as a result of the reaction between the functional group A and the hydroxyl group of the linking compound, such as a urethane bond, an ester bond, or an ether bond.

また、連結用化合物Ｌとして３官能性連結用化合物を用いた場合には、下記式（４ｂ）で表わされるような３量体化以上の多量体型ポリオールが得られることになり、ポリオール（ａ−１）として、水酸基が３個以上のポリオールを用いた場合には、例えば、下記式（４ｃ）で表わされるような３量体化以上の多量体型ポリオールが得られることになる。

Further, when a trifunctional linking compound is used as the linking compound L, a multimer-type polyol having a trimerization or higher as represented by the following formula (4b) is obtained. When a polyol having 3 or more hydroxyl groups is used as 1), for example, a multimeric polyol having a trimerization or more as represented by the following formula (4c) can be obtained.

また、２官能性の連結用化合物Ｌ、水酸基が２個の共役ジエン系水添ポリマーポリオールを用いた場合であっても、反応条件により、２量体化共役ジエン系水添ポリマーポリオール分子鎖末端のＯＨ基と連結用化合物Ｌとがさらに反応して、３量体化（下記式（４ｄ））のように多量体化された共役ジエン系水添ポリマーポリオールが合成され得る。

In addition, even when a bifunctional linking compound L and a conjugated diene hydrogenated polymer polyol having two hydroxyl groups are used, depending on the reaction conditions, a dimerized conjugated diene hydrogenated polymer polyol molecular chain terminal Then, the OH group and the linking compound L further react to synthesize a conjugated diene-based hydrogenated polymer polyol that has been polymerized as shown in trimerization (formula (4d) below).

２量体化、３量体化のように多量体化することにより、単なる共役ジエン化合物の重合による合成あるいは入手が困難な高分子量の共役ジエン系水添ポリマーポリオールを得ることができる。

Higher molecular weight conjugated diene-based hydrogenated polymer polyols that are difficult to synthesize or obtain by simply polymerizing a conjugated diene compound can be obtained by multimerization such as dimerization and trimerization.

  However, in the case of multimerization more than trimerization, gelation may occur due to multimerization, so depending on the type of polyol used, the type of functional group contained in the linking compound L, the number of functional groups, It is preferable to select according to reaction conditions that do not cause gelation and the number of multimers (molecular weight) of the target multimeric conjugated diene hydrogenated polymer polyol.

  The mixing ratio of the polyol (a-1) and the connecting compound L may be 0.3 to 0.9 equivalents of the hydroxyl group in (a-1), and the connecting compound L may be added. Is appropriately selected according to the number of functional groups and reaction conditions.

The addition of the linking compound L is preferably carried out by the dropping method at 60 to 70 ° C. for about 10 minutes to 3 hours in the reaction system charged with the conjugated diene hydrogenated polymer polyol (a-1). .
[(A-2) α, β Unsaturated Carbonyl Compound Having Functional Group Reacting with Hydroxyl Group]
The α, β-unsaturated carbonyl conjugated diene hydrogenated polymer as component A includes (a-1) an α, β-unsaturated carbonyl compound (a-) having a functional group that reacts with a hydroxyl group of the conjugated diene-based hydrogenated polymer polyol. It is obtained by reacting with 2).

  The α, β unsaturated carbonyl compound (a-2) (hereinafter referred to as “hydroxyl-reactive unsaturated carbonyl compound” or “unsaturated carbonyl compound (a-2)”) having a functional group that reacts with a hydroxyl group is It is a compound represented by Formula (5).

（５）式中、Ｑが水酸基と反応する官能基、又は水酸基と反応する官能基を有する原子団である。水酸基と反応する官能基としては、イソシアナート基又はカルボキシル基が用いられる。また、不飽和カルボニル基は、カルボニルと結合する原子の価数に応じて、１又は２個含まれ得る。従って、水酸基と反応する官能基を有するα，β不飽和カルボニル化合物（ａ−２）は、具体的には、下記一般式（５ａ）で表わされる不飽和カルボン酸、又は下記一般式（６ａ）若しくは（６ｂ）で表わされるイソシナート基含有不飽和カルボニル化合物、又は下記一般式（７）で表わされるカルボキシル基含有不飽和カルボニル化合物が該当する。

(5) In the formula, Q is a functional group that reacts with a hydroxyl group, or an atomic group that has a functional group that reacts with a hydroxyl group. As the functional group that reacts with the hydroxyl group, an isocyanate group or a carboxyl group is used. In addition, one or two unsaturated carbonyl groups may be included depending on the valence of the atom bonded to the carbonyl. Accordingly, the α, β unsaturated carbonyl compound (a-2) having a functional group that reacts with a hydroxyl group is specifically an unsaturated carboxylic acid represented by the following general formula (5a) or the following general formula (6a). Alternatively, the isocyanato group-containing unsaturated carbonyl compound represented by (6b) or the carboxyl group-containing unsaturated carbonyl compound represented by the following general formula (7) is applicable.

上記一般式（５），（５ａ），（６ａ），（６ｂ），（７）において、Ｒ^１，Ｒ^２，Ｒ^３は、それぞれ、水素、又はメチル、エチル、プロピル等の炭素数１〜６の直鎖状又は分枝状アルキル基を示し、Ｒ^１とＲ^２は同じでも異なっていてもよい。また、Ｒ^３は、Ｒ^１，Ｒ^２と同じであっても異なっていてもよい。

In the general formulas (5), (5a), (6a), (6b), and (7), R ¹ , R ² , and R ³ each represent hydrogen or a carbon number of 1 to 1 such as methyl, ethyl, propyl, etc. 6 linear or branched alkyl groups, R ¹ and R ² may be the same or different. R ³ may be the same as or different from R ¹ and R ² .

  In the formulas (4a), (4b) and (5), X, X ′ and Y are intervening groups and are linear or branched having 1 to 6 carbon atoms such as methylene, ethylene, propylene, trimethylene and tetramethylene. An alkylene group, preferably methylene or ethylene. X and X 'may be the same or different, but are preferably the same.

  Accordingly, among the α, β unsaturated carbonyl compound (a-2), examples of the unsaturated carboxylic acid in which Q is a hydroxyl group include acrylic acid, methacrylic acid, crotonic acid, tiglic acid, angelic acid, and the like. Of these, acrylic acid and methacrylic acid are preferably used.

  Among the α, β unsaturated carbonyl compounds (a-2), the isocyanato group-containing unsaturated carbonyl compounds include 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate, 1,1-bis (acryloyl). And oxymethyl) ethyl isocyanate.

  Moreover, 2-acryloyloxyethyl succinic acid etc. can be used as a carboxyl group-containing unsaturated carbonyl compound represented by General formula (5) among (alpha), (beta) unsaturated carbonyl compound (a-2).

As the unsaturated carbonyl compound having the above-described configuration, an acryloyl group or a methacryloyl group in which R ¹ is hydrogen or a methyl group and R ² is hydrogen in an α, β unsaturated carbonyl group is preferably used.
[Synthesis of unsaturated carbonyl-modified conjugated diene hydrogenated polymer (A): reaction of conjugated diene hydrogenated polymer polyol (a-1) with unsaturated carbonyl compound (a-2)]
Conjugated diene hydrogenated polymer polyol (single conjugated diene hydrogenated polymer polyol, multimeric conjugated diene hydrogenated polymer, or a mixture thereof) (a-1) and a hydroxyl-reactive unsaturated carbonyl compound (a-2) ) Reacts with an isocyanate group or a carboxyl group in the unsaturated carbonyl compound (a-2) to form a urethane bond or an ester bond. Then, an unsaturated carbonyl-modified conjugated diene hydrogenated polymer (A) in which an unsaturated carbonyl group is introduced via a urethane bond or an ester bond is synthesized.

  (A-1) When a unit type conjugated diene-based hydrogenated polymer polyol is used as the component, the unsaturated carbonyl conjugated diene-based hydrogenated polymer is, as shown by the formula (8a), a conjugated diene-based hydrogenated polymer part. It becomes a simple type unsaturated carbonyl conjugated diene-based hydrogenated polymer (A2) having only one. When a multimeric conjugated diene hydrogenated polymer polyol is used as the component (a-1), a multimeric unsaturated carbonyl-modified conjugated diene hydrogenated polymer (A1) having a plurality of conjugated diene hydrogenated polymer parts is obtained. For example, when a dimerized conjugated diene hydrogenated polymer polyol represented by the above formula (4a) is used, an unsaturated carbonyl-modified dimerized conjugated diene hydrogenated polymer represented by the following formula (8b): Is obtained. The multimeric unsaturated carbonyl-modified conjugated diene hydrogenated polymer (A1) usually has a multimeric structure corresponding to the structure of the multimeric conjugated diene hydrogenated polymer polyol used as the component (a-1). .

式（８ａ）（８ｂ）中、Ｙは共役ジエン系水添ポリマーポリオール末端の水酸基と水酸基反応性不飽和カルボニル化合物（ａ−２）との反応により形成されるウレタン結合又はエステル結合である。

In the formulas (8a) and (8b), Y is a urethane bond or an ester bond formed by the reaction between the hydroxyl group at the terminal of the conjugated diene-based hydrogenated polymer polyol and the hydroxyl-reactive unsaturated carbonyl compound (a-2).

  The number average molecular weight and viscosity of the resulting unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer vary depending on the type of conjugated diene used as a repeating unit, the presence or absence of multimerization, etc., but generally the molecular weight and viscosity increase due to multimerization. As the number of multimers increases, the molecular weight and viscosity further increase.

  Specifically, the number average molecular weight of the unitary unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer (A2) is usually 500 to 40000, preferably 1000 to 30000, although it depends on the type of conjugated diene as a repeating unit. More preferably, it is 1500-10000, More preferably, it is 2000-8000, Most preferably, it is 2000-5000. The viscosity at 25 ° C. is 3 to 4000 Pa · s, preferably 3 to 1000 Pa · s, more preferably 20 to 800 Pa · s, although it varies depending on the type of conjugated diene serving as a repeating unit, reaction conditions, and the like.

  The number average molecular weight of the multimeric unsaturated carbonyl-modified conjugated diene hydrogenated polymer (A1) depends on the type of conjugated diene as a repeating unit and the number of linkages of the conjugated diene hydrogenated polymer. It becomes 1000-100,000, Preferably it is 1000-60000, More preferably, it is 3000-50000, More preferably, it is 5000-40000, More preferably, it becomes 8000-30000 by a merification. The viscosity at 25 ° C. is 10 to 6000 Pa · s, preferably 10 to 2000 Pa · s, although it varies depending on the type of conjugated diene serving as a repeating unit, reaction conditions, and the like.

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

Hereinafter, hydrogenated polybutadiene polyol is used as the conjugated diene-based hydrogenated polymer polyol (a-1), R ¹ is hydrogen or a methyl group, and R ² is hydrogen as the unsaturated carbonyl compound (a-2) (meta ) A method for carbonyl modification will be described in detail with a (meth) acryloyl-modified conjugated diene-based hydrogenated polymer obtained by using an acryloyl group-containing compound as a representative.

  The production method of the (meth) acryloyl-modified hydrogenated polybutadiene is not particularly limited. Usually, in the presence of a catalyst, a hydrogenated polybutadiene polyol and an unsaturated carbonyl compound (a-2) in which the unsaturated carbonyl group is a (meth) acryloyl group. And the hydroxyl group of the hydrogenated polybutadiene polyol can be obtained by urethanization or esterification.

  The mixing ratio of the hydrogenated polybutadiene polyol and the (meth) acryloyl compound is consumed by the reaction with the linking compound L from 1 equivalent of hydroxyl group contained in the hydrogenated polybutadiene polyol (hydroxyl equivalent based on the charged amount of hydrogenated polybutadiene polyol). It is preferable that the functional group contained in the (meth) acryloyl compound (a-2) be 0.30 to 1.05 equivalent, more preferably 0.40 to 1.05 equivalent. When the amount is less than 0.3 equivalent, hydroxyl groups that are not modified with (meth) acryloyl tend to remain, and the resulting cured product tends to have low curability. On the other hand, when it exceeds 1.05 equivalent, the tendency for the heat resistance of a hardened | cured material and the fall of light resistance to occur for the reason of excess (meth) acryloyl compound (a-2) remaining etc. is not preferable. Further, most of the (meth) acryloyl compound (a-2) used, specifically 90% or more, preferably 95% or more, more preferably 98% or more reacts to form a connecting part. Preferably it is.

  Examples of the catalyst used in the reaction include amines such as triethylamine and benzylmethylamine, dilaurate compounds such as dibutyltin dilaurate and dioctyltin dilaurate, copper naphthenate, cobalt naphthenate, and zinc naphthenate. The amount of the catalyst added is preferably about 0.001 to 1% by mass, particularly preferably about 0.01 to 0.5% by mass, based on the entire reaction mixture.

  The reaction temperature is usually 10 to 100 ° C, particularly preferably 30 to 80 ° C. In order to prevent gelation due to radical polymerization during the reaction, it is preferable to add a known polymerization inhibitor. As the polymerization inhibitor, for example, hydroquinone, methoquinone, p-methoxyphenol, p-benzoquinone and the like can be preferably used, and it is preferably 0.001 to 3% by mass with respect to the entire reaction mixture, 0.01 to 1 More preferably, it is mass%.

The α, β-unsaturated carbonyl-modified conjugated diene hydrogenated polymer having the above configuration tends to obtain a cured product having a low dielectric constant. For example, in a hydrogenated butadiene-based polymer, the dielectric constant at 1 MHz is 3.3 or less, and by devising other components to be blended, it is possible to achieve 3.0 or less, preferably 2.8 or less. Therefore, it can be suitably applied to adhesives, fillers, and the like between transparent members such as capacitive touch panels, which have strict requirements on the dielectric constant.
(B) Photopolymerization initiator As the photopolymerization initiator (B), a photopolymerization initiator conventionally used in the field of energy beam curable resin compositions can be used. For example, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1- Hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone, oligo { 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone}, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) benzyl] phenyl}- Acetophenones such as 2-methylpropan-1-one; benzoin, benzoin methyl ether Benzoins such as benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether; benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3 ', 4 , 4′-tetra (t-butylperoxycarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyloxy) ethyl] Benzophenones such as benzenemethananium bromide and (4-benzoylbenzyl) trimethylammonium chloride; 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxa Thioxanthones such as 1-chloro-4-propoxythioxanthone, 2- (3-dimethylamino-2-hydroxy) -3,4-dimethyl-9H-thioxanthone-9-one mesochloride; 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-trimethylbenzoyl)- Examples thereof include phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. Among them, acetophenones, oxy-phenyl-acetic acid 2- [2-oxo-2-phenyl-acetoxy-ethoxy] ethyl ester, and oxy-phenyl-acetic acid 2- [2-hydroxy-ethoxy] ethyl ester are preferable. It is.

The content of the photopolymerization initiator in the energy ray curable resin composition varies depending on the use, but is usually 0.1 to 10% by mass with respect to 100% by mass of the resin composition. . When the content is 0.1% by mass or more, the resin composition can be sufficiently cured, and when the content is 10% by mass or less, generation of odor and coloring of the cured product can be sufficiently suppressed. More preferably, it is 0.3-5 mass%, More preferably, it is 0.3-3 mass%.
(C) Polymerizable component The resin composition of the present invention contains (C1) a (meth) acrylate compound having a hydrophilic group, and (C2) other polymerizable components as the polymerizable component.
(C1) Hydrophilic group-containing (meth) acrylate compound
“Hydrophilic group-containing (meth) acrylate compound” as component C is a (meth) acrylate monomer or oligomer that can be co-cured with an α, β unsaturated carbonyl-modified conjugated diene polymer and has a hydrophilic group. A compound.

  By including such a hydrophilic group-containing (meth) acrylate-based compound, it is possible to suppress a decrease in transparency under high humidity. That is, the cured product of the α, β-unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer has low initial transparency, but its transparency is lowered by leaving it under high humidity conditions. There is a problem that the transparency does not recover even when the state is restored. However, it has been found that the decrease in transparency can be significantly improved by adding the (C1) hydrophilic group-containing (meth) acrylate compound.

  Examples of the hydrophilic group in the “hydrophilic group-containing (meth) acrylate compound” include a hydroxyl group, mercapto group, carboxyl group, sulfo group, phosphono group, oxyphosphono group, amide group, 2-pyrrolidone, and PEG chain. Typically, it is a (meth) acrylate compound having a hydroxyl group as a hydrophilic group. Specifically, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4-hydroxybutyl (Meth) acrylate, 2-hydroxyalkyl (meth) acryloyl phosphate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, neopentyl glycol mono (meth) acrylate, and the like. Among these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and the like are preferable, and 2-hydroxypropyl (meth) acrylate is more preferable. This is because a compound having a high hydroxyl content in the compound tends to provide a high effect of improving moisture resistance with a small amount of addition.

It is preferable to contain 1-10 mass% of such a hydrophilic group containing (meth) acrylate type compound with respect to the whole resin composition, More preferably, it is 1-5 mass%. If it is less than 1% by mass, the moisture resistance effect is insufficient. On the other hand, as the content of the hydroxyl group-containing (meth) acrylate compound increases, the dielectric constant of the cured product tends to increase, and the effect of lowering the dielectric constant due to the use of the conjugated diene hydrogenated polymer is impaired. It tends to be. Therefore, the hydroxyl group-containing (meth) acrylate compound is preferably less than 10% by mass, more preferably less than 5% by mass. In particular, when (meth) acryloyl-modified hydrogenated polybutadiene is used as the component (A), the moisture resistance of the cured product can be satisfied even if it is less than 5 parts by mass.
(C2) Other polymerizable component As the polymerizable component, in addition to the hydrophilic group-containing (meth) acrylate compound (C1), a (meth) acrylate monomer that can be co-cured with an α, β-unsaturated carbonyl-modified polymer. (Excluding hydroxyl group-containing (meth) acrylate compounds) or oligomers and vinyl group-containing compounds may be contained. While reducing the content of the hydrophilic group-containing (meth) acrylate compound (C1) and increasing the content of the other polymerizable component (C2), the viscosity and workability of the resulting resin composition can be easily achieved. Can be adjusted. Furthermore, physical properties such as heat resistance, light resistance, and transparency can be adjusted.

  Although it does not specifically limit as said (meth) acrylate type compound, Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t -Butyl (meth) acrylate, pentyl (meth) acrylate, neopentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate , N-octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, u Decyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, isomyristyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl Alkyl (meth) acrylates such as (meth) acrylate, nonadecyl (meth) acrylate, eicodecyl (meth) acrylate, and n-lauryl (meth) acrylate; (meth) acryloylmorpholine, cyclohexyl (meth) acrylate, dicyclopentenyl ( Alicyclic alkyl (meth) acrylates such as (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and dicyclopentanyl (meth) acrylate Aromatic alkyl (meth) acrylates such as phenyl (meth) acrylate and benzyl (meth) acrylate; esters of (meth) acrylic acid such as isobornyl (meth) acrylate with terpenes; alkyl glycidyl ether, allyl glycidyl ether, glycidyl ( A compound obtained by addition reaction of a glycidyl group-containing compound such as (meth) acrylate and (meth) acrylic acid, tricyclodecane dimethanol di (meth) acrylate, 1,6 hexanediol di (meth) acrylate, bisphenol A ( Bifunctional (meth) acrylates such as those reacted with meth) acrylic acid; trimethylolpropane tri (meth) acrylate, glycerin tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythris Trifunctional or higher functional (meth) acrylates such as lithol tetra (meth) acrylate and dipentaerythritol hexa (meth) acrylate; and various modified (added ethylene oxide and / or propylene oxide to the above (meth) acrylate ( Meth) acrylates; methoxy-polyethylene glycol (meth) acrylate, ethoxy-polyethylene glycol (meth) acrylate, butoxy-polyethylene glycol (meth) acrylate, phenoxy-diethylene glycol (meth) acrylate, phenoxy-triethylene glycol (meth) acrylate, etc. (Meth) acrylate with one end of alkylated ethylene glycol or polymer thereof, methoxy-polypropylene glycol (meth) acrylate One end alkylated propylene glycol such as ethoxy-polypropylene glycol (meth) acrylate, butoxy-polypropylene glycol (meth) acrylate, phenoxy-dipropylene glycol (meth) acrylate, phenoxy-tripropylene glycol (meth) acrylate or the like (Meth) acrylate with polymer; amino group-containing (meth) acrylate such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate, carboxyl such as (meth) acrylic acid and 2-acryloyloxyethyl succinic acid (Meth) acrylates such as group-containing (meth) acrylates, urethane (meth) acrylate resins, polyester (meth) acrylate resins, epoxy (meth) acrylate resins And reactive oligomers having a salt.

  The vinyl group-containing compound is not particularly limited, but styrenes such as styrene, α-methylstyrene, vinyltoluene, and chlorostyrene; vinyl esters such as vinyl acetate; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, and butyl vinyl ether. Allyl compounds such as allyl alcohol, allyl glycidyl ether, ethylene glycol monoallyl ether and propylene glycol monoallyl ether; N-substituted maleimides such as N-phenylmaleimide, N-cyclohexylmaleimide and N-isopropylmaleimide; N- N-vinyl compounds such as vinylpyrrolidone, N-vinylcaprolactam, N-vinyl-N-methylformamide, N-vinylimidazole, N-vinylacetamide, and 2- (meth) acrylic acid 2-bi Roxyethyl, 3-vinyloxyethyl (meth) acrylate, 2-vinyloxypropyl (meth) acrylate, 1-methyl-2-vinyloxyethyl (meth) acrylate, 4-vinyloxybutyl (meth) acrylate, (meth) acrylic acid 6 -Vinyloxyhexyl, (meth) acrylic acid 4-vinyloxycyclohexyl, (meth) acrylic acid 4-vinyloxymethylcyclohexylmethyl, (meth) acrylic acid 2- (2-vinyloxyethoxy) ethyl, (meth) acrylic acid 2- (2-vinyloxyisopropoxy) propyl, 2- (2- (2-vinyloxyethoxy) ethoxy) ethyl (meth) acrylate, diallyl isophthaldiphenate, diallyl phthalate diallyl, triallyl cyanurate, triallyl isocyanurate Allyl ester monomers such as Vinyl ether monomers such as reethylene glycol divinyl ether, cyclohexane dimethanol divinyl ether, hydroxybutyl vinyl ether, dodecyl vinyl ether; trimethylolpropane diallyl ether, pentaerythritol triallyl ether, allyl glycidyl ether, allyl ether of methylol melamine, adipine of glycerol diallyl ether Allyl ether monomers such as allyl ethers of acid esters, allyl acetals, methylol glyoxalureins; Maleate ester monomers such as diethyl maleate and dibutyl maleate; Fumarate monomers such as dibutyl fumarate and dioctyl fumarate Is mentioned.

The other polymerizable component (C2) as described above is preferably contained in a larger amount than the hydrophilic group-containing polymerizable component, and specifically, it is blended at a ratio of 1 to 35% by mass of the entire resin composition. Is more preferable, more preferably 2 to 20% by mass, still more preferably 5 to 20% by mass.
(D) Other non-reactive resin The energy ray-curable resin composition of the present invention comprises (A) a carbonyl-modified conjugated diene-based hydrogenated polymer, (B) a photopolymerization initiator, and (C) a hydrophilic group-containing (meth). In addition to the polymerizable component containing the acryloyl compound (C1), other non-reactive resins other than the carbonyl-modified conjugated diene polymer (A) may further be included as necessary.

  By containing other non-reactive resins, the viscosity of the resin composition, the physical properties of the cured product, and the like can be adjusted.

  Other non-reactive resins that can be used in the present invention include polyethylene glycol, polypropylene glycol, polyether polyols such as ethylene oxide and propylene oxide copolymers; polyolefin resins such as polyethylene, polypropylene, and polystyrene; polymethyl methacrylate, poly (Meth) acrylic polymers having no polymerizable functional group or double bond in the side chain such as acrylic acid; polyester resins such as polyethylene terephthalate; polyamide resins such as nylon 6 and 6, polyisoprene, polybutadiene, polybutene Or conjugated diene polymers such as hydrogenated products thereof; thermoplastic elastomers, terpene resins, terpene phenol resins, modified terpene resins, hydrogenated terpene resins, rosin ester resins, and the like.

  Of these, hydrophobic resins such as rosin ester resins and liquid conjugated diene polymers (hydrogenated or non-hydrogenated) are used from the viewpoint of affinity with unsaturated carbonyl-modified conjugated diene-based hydrogenated polymers. The conjugated diene polymer is more preferably a liquid conjugated diene polymer, more preferably a conjugated diene polymer of the same type as the conjugated diene polymer used as the component (A). For example, when the component (A) is α, β-unsaturated carbonyl-modified hydrogenated polybutadiene, it is preferable to use liquid (hydrogenated) polybutadiene as the non-reactive resin. When a highly hydrophilic resin is used, the compatibility with the unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer (A) is low, the uniformity of the resin composition tends to decrease, and the transparency of the resulting resin composition is low. It tends to cause a drop. On the other hand, transparency is improved by containing a non-reactive resin having high affinity.

The other non-reactive resins as described above are preferably blended in a proportion of 0 to 35% by mass of the entire resin composition, more preferably 0 to 20% by mass, and still more preferably 0 to 20% by mass. .
(E) Other fillers (E1) Plasticizer In addition to the above components, a plasticizer may be contained as necessary. The plasticizer is a conventionally known plasticizer, for example, a compound having no (meth) acrylate group. For example, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, diisononyl phthalate, di-2- Phthalic acid esters such as ethylhexyl phthalate, dibenzyl phthalate, diisodecyl phthalate, ditridecyl phthalate, diundecyl phthalate; di-n-butyl adipate, diisobutyl adipate, dibutoxyethyl adipate, di-n-octyl adipate, diisooctyl adipate , Diisononyl adipate, bis-2-ethylhexyl adipate, adipic acid esters such as diisodecyl adipate; dibutyl sebacate, dioctyl sebacate, di-2 Sebacic acid esters such as ethylhexyl sebacate; azelaic acid esters such as dihexyl azelate and dioctyl azelate; citrate esters such as triethyl citrate, acetyl triethyl citrate and tri-n-butyl citrate; methylphthalyl Glycolic acid esters such as ethyl glycolate and ethylphthalyl ethyl glycolate; Trimerit such as trioctyl trimellitate, tri-n-octyl-n-decyl trimellitate, trimellitic acid trialkyl (C4 to C11) Acid esters; ricinoleic acid esters such as methyl acetyl ricinoleate, butyl acetyl ricinolate and glycerin monoricinoleate; maleic acid esters such as di-n-butyl malate; itaconic acid esters such as monobutyl itaconate ; Oleic acid esters such as Buchiruoreto; tricresyl phosphate, trioctyl phosphate, triphenyl phosphate, esters such as phosphoric acid esters such as trixylenyl phosphate.
(E2) Other fillers The energy ray curable resin composition of the present invention further includes a plasticizer, a thermosetting catalyst, an ultraviolet absorber, a chain transfer as long as it does not impair the effects of the present invention as required. Stabilizers, light stabilizers, polymerization inhibitors, antioxidants, leveling agents, thickeners, thickeners, thixotropic agents, defoamers, colorants, and the like may also be included.

In addition, as a thixotropy imparting agent, an inorganic thixotropy imparting agent is preferable. This will be described in detail below.
(E3) Thixotropy imparting agent The resin composition of the present invention preferably contains a thixotropy imparting agent. The thixotropy-imparting agent is not particularly limited as long as it can impart thixotropy to the resin composition. For example, organic cellulose acetate, disparon (trade name, manufactured by Enomoto Kasei Co., Ltd.), urea urethane resin, Other examples include polymers and inorganic thixotropy imparting agents described later. Particularly preferred are inorganic thixotropic agents.
The inorganic thixotropy imparting agent is not particularly limited as long as it contains an inorganic substance and can impart thixotropy to the resin composition. For example, colloidal silica, fumed silica, silica aerogel, Organic modified clay, clay, silica powder, Aerosil (trade name, manufactured by Nippon Aerosil Co., Ltd.), Thixogel (trade name, manufactured by Yokohama Kasei Co., Ltd.), Leoroseal (trade name, manufactured by Tokuyama Co., Ltd.), and the like.
As the inorganic thixotropy imparting agent, inorganic fine particles are used, and inorganic metal oxide fine particles are preferable. The average particle size is 50 μm or less, preferably 0. Those having a particle diameter of 0 1 to 20 μm and a maximum particle diameter of 100 μm or less (preferably 80 μm or less) are preferably used. When the average particle size exceeds 50 μm, it becomes difficult to obtain a resin composition having a thixotropic coefficient of 1.1 or more, and when the maximum particle size exceeds 100 μm, the adhesion tends to be insufficient.
The addition amount of the thixotropy imparting agent (preferably inorganic) is preferably 0.1 to 10% by mass with respect to 100% by mass of the total amount of the resin composition. More preferably, it is 0.5-10 mass%, More preferably, it is 0.5-8 mass%, Most preferably, it is 1-5 mass%, Most preferably, it is 1-3 mass%. When such a thixotropy imparting agent (preferably inorganic) is added and a resin composition having a thixotropy index (TI) value adjusted to a range of 1.1 to 10.0 is used, it is used for a display device. When sticking at least any two selected from the group consisting of a display panel, a protective plate, and a sheet-like functional member, protrusion of the resin composition and stringing are reduced.

  The thixotropic index (TI) value is 1.1 to 10.0, more preferably 1.1 to 8.0, still more preferably 1.1 to 6.0, and particularly preferably 1.1 to 5.0. Most preferably, it is 2.0 to 5.0. If the thixotropy index (TI) value is less than 1.1, stringing of the resin composition tends to increase.

Here, the thixotropy is a formula; TI = η3 / η30 (wherein η3 is a viscosity (25 ° C.) measured at a rotational speed of 3 rpm for a predetermined liquid resin composition,
η30 is the viscosity (25 ° C.) of the composition measured at a rotation speed of 30 rpm. )
It can be evaluated by a thixotropy index (TI) value defined in the above, and a higher thixotropy index (TI) value indicates higher thixotropy.

  The metal oxide fine particles, which are particularly preferable inorganic thixotropy imparting agents, are oxide fine particles made of one kind of metal or fine particles of an oxide made of two or more kinds of metals (ie, complex oxide). Also good. Specific examples of oxides made of one kind of metal include oxides of metals such as silicon, aluminum, magnesium, zirconium, and titanium, such as silica (SiO2), alumina (Al2O3), titania (TiO2), and zirconia ( ZrO2) and the like. Specific examples of the composite oxide include silica-alumina composite oxide, silica-titania composite oxide, silica-zirconia composite oxide, silica-magnesia composite oxide, and alumina-magnesia composite, which are composite oxides of the above metals. Binary composite oxides such as oxide, ternary composite oxides such as silica-alumina-magnesia composite oxide, silica-alumina-titania composite oxide, silica-titania-magnesia composite oxide, etc. . Among these metal oxide fine particles, metal oxide fine particles containing silica fine particles as a main component (that is, containing 60 to 100% by weight) are preferable.

Examples of metal oxide fine particles include molten metal oxide powder, crushed metal oxide, fumed metal oxide synthesized by high-temperature gas phase reaction (fumed metal oxide), and metal oxide synthesized by a wet method. It is done.
The metal oxide fine particles need not be surface-treated, but the surface may be treated with silazanes and / or a silane coupling agent.
As the metal oxide fine particles, commercially available products such as R200, R255, R300, R380, R972, R812, RX200, RY300, NX90, and NAX50 manufactured by Nippon Aerosil Co., Ltd. are preferable, the hydrophilicity is high, and the specific surface area is 200 to 200. Particularly preferred are R200, R255, R300, and R380, which are fine particle regions within a range of 400 m 2 / g.
The average particle diameter of the metal oxide fine particles is preferably 0.001 μm to 10 μm, and more preferably 0.005 μm to 0.040 μm. When the average particle diameter is in this range, good thixotropic properties can be obtained, and a uniform and transparent cured product can be obtained without causing stringing or bleeding.

  Specific examples of the thermosetting catalyst include benzoyl peroxide, lauroyl peroxide, methyl ethyl ketone peroxide, t-butyl peroxy-2-ethyl hexanoate, t-butyl peroxy octoate, and t-butyl. Organic peroxides such as peroxybenzoate, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, bis (4-t-butylcyclohexyl) peroxydicarbonate; azobisisobutyronitrile, 2-phenylazo-2 An azo compound such as 4-dimethyl-4-methoxyvaleronitrile is not particularly limited. These thermosetting catalysts may be used alone or in combination of two or more. The addition amount of the curing catalyst with respect to the monomer component is not particularly limited.

  The chain transfer stabilizer is preferably used for adjusting the hardness of the cured product, improving adhesion to the substrate, and improving heat shock resistance. Specific examples of the chain transfer agent include β-mercaptopropionic acid, methyl-3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, n-octyl-3-mercaptopropionate, and methoxybutyl. -3-mercaptopropionate, stearyl-3-mercaptopropionate, 3,3'-thiodipropionic acid, dimethyl 3,3'-thiodipropionate, dithiodipropionic acid, laurylthiopropionic acid, thioglycol Monothiols such as acid, ammonium thioglycolate, monoethanolamine thioglycolate; trimethylolpropane tris (3-mercaptopropionate), tris-[(3-mercaptopropionyloxy) -ethyl] -isocyanurate, penta Erythritol tetrakis 3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), tetraethylene glycol bis (3-mercaptopropionate), tetraethylene glycol bis (3-mercaptopropionate), dipentaerythritol hexakis Polyfunctional thiols such as (3-mercaptopropionate) and diammonium dithioglycolate are exemplified, and polyfunctional thiols are preferred. These can be used alone or in combination.

  The light stabilizer is effective not only for improving light resistance but also for improving heat resistance. As the light stabilizer, a hindered amine light stabilizer is preferably used. Specific examples include TINUVIN 123, 144, 152, 292, 5100, 765 manufactured by BASF, and SANOL LS-770, 765, 292, 2626 manufactured by Sankyo Co., Ltd.

  A commercially available ultraviolet absorber may be used. For example, salicylic acid esters such as benzotriazoles, benzoates, cyanoacrylates, benzophenones, phenyl salicylate, pt-butylphenyl salicylate, p-octylphenyl salicylate; TINUVIN 770, 123, 144 622 (above, product name of Ciba Geigy), SANOL LS-770,765,292, 2626 (above, product name of Sankyo Co., Ltd.), Adekastab LA-52,57,62 (above, product of Asahi Denka Co., Ltd.) Hindered amines such as name) can be used.

  Examples of the antioxidant include commercially available ADK STAB AO-10 to AO-80, ANTAGE W-300, W-400, and W-500. AO-50 and AO-60 are preferably used from the viewpoint of durability.

  When the energy ray curable resin composition is used as a printing ink, it usually contains a colorant. Examples of the colorant include an azo lake pigment, an insoluble azo pigment, a condensed azo pigment, a chelate azo pigment, a phthalocyanine pigment, an anthraquinone pigment, a perylene pigment, a quinacrine pigment, an isoindoline pigment, a benzimidazolone pigment, a thioindigo pigment, a dioxazine pigment, and a quinophthalone. Organic pigments such as pigments, nitro pigments and aniline black; inorganic pigments such as titanium oxide and carbon black; dyes and the like can be used. Since the viscosity of the resin composition of the present invention can be increased, the pigment can be stably dispersed.

  The other components as described above are appropriately selected depending on the use of the resin composition, but are usually preferably 0 to 40% by mass, more preferably 0 to 20% by mass, and particularly preferably 0 to 10% by mass. %.

In addition, it is preferable that the content rate of the unsaturated carbonyl modified conjugated diene type hydrogenated polymer which concerns on this invention shall be 10-70 mass% of the whole resin composition, More preferably, it is 10-40 mass%. This is because a preferable balance between hardness and dielectric constant can be obtained within this range.
[Method of using energy ray curable resin composition]
As an application and coating method of the energy ray-curable resin composition having good thixotropy of the present invention, brush coating, roller coating, bar coater, applicator, air knife coater, curtain, which are employed in conventional coating liquids In addition to a coating method such as a coater, the coating can be performed using a device that can be dropped and discharged at a constant rate, such as a dispenser. When a device capable of adjusting and discharging with a small amount such as a pressure-feed dispenser is used, it can be applied to a limited region having a width of about 0.5 to 3.0 mm.

  Since the unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer has a high viscosity, a highly viscous resin composition can be obtained even when a polymerizable component and other non-reactive resin are blended. For this reason, it is also possible to apply screen printing in which the ink is transferred with a squeegee to the part where the coating part is defined by the printing frame. Since there is little flow out and sagging before application and curing, the thickness of the coating film can be made as thick as 0.1 to 4.0 mm.

  The energy ray curable resin composition of the present invention having the above composition reacts with the unsaturated carbonyl group in the unsaturated carbonyl-modified conjugated diene hydrogenated polymer and the polymerizable component (C) by energy ray irradiation. Harden. When the hydrophilic group-containing polymerizable component (C1) participates and co-cures with the unsaturated carbonyl-modified conjugated diene hydrogenated polymer, a hydrophilic group is introduced into the cured product of the conjugated diene hydrogenated polymer. In addition, hardening here means making it a state without fluidity | liquidity.

As the energy rays, electron beams, radiation, ultraviolet rays, and the like can be used, and ultraviolet rays having a wavelength of 150 to 450 nm are preferable. Examples of the light source that emits such a wavelength include sunlight, 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, and a carbon arc lamp. Irradiation integrated light quantity is preferably 0.1~10J / cm ^2, more preferably 0.2~5J / cm ^2, more preferably in the range of 0.3~3J / cm ^2.

  It is possible to use both curing by light irradiation and curing by heating. In this case, infrared light, far infrared light, hot air, high frequency heating, or the like may be used together with the light source described above. The heating temperature may be appropriately adjusted according to the decomposition temperature of the thermosetting catalyst, the type of base material used, and the like, and is not particularly limited, but is preferably 50 to 150 ° C, more preferably 50 to 100 ° C. More preferably, it exists in the range of 60-90 degreeC. The heating time may be appropriately adjusted according to the decomposition temperature or coating thickness of the thermosetting catalyst, and is not particularly limited, but is preferably 1 minute to 12 hours, more preferably 10 minutes to 6 hours, Preferably, it is within the range of 10 minutes to 3 hours.

Furthermore, you may obtain by using together hardening by electron beam irradiation with hardening by light irradiation. In this case, the acceleration voltage is preferably 0 to 500 kV, more preferably 20 to 300 kV, and even more preferably 30 to 200 kV. The irradiation amount is preferably in the range of 2 to 500 kGy, more preferably 3 to 300 kGy, and still more preferably 4 to 200 kGy.
<Hardened product of resin composition>
The energy ray curable resin composition of the present invention, depending on the content of unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer, composition, and type of unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer, A transparent cured product having a low dielectric constant and excellent heat resistance, light resistance and moisture resistance can be obtained. Therefore, conventionally known applications such as adhesives and fillers between optical display members (for example, a cured resin layer interposed between an image display unit and a protection unit of an image display device), and further a capacitance It can be suitably used as a filler, an adhesive, or the like between transparent members of a type touch panel.

Furthermore, when a multimeric unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer is used, it is possible to obtain a cured product that is softer than a single-unit unsaturated carbonyl-conjugated diene-based hydrogenated polymer. Specifically, based on JIS K7312, the hardness of a test piece (width 17 mm × length 45 mm × thickness 4 mm) to be measured using an ASKER durometer C type hardness tester is 5 to 60, more preferably 8 A cured product of -40, more preferably 10-30 can be obtained. Therefore, the energy ray curable resin composition of the aspect using the multimer type unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer as the component A is excellent in impact absorption and, in turn, excellent in image formation durability. It can also be suitably used for a filler, an adhesive, and the like between transparent members of a portable image display device in which importance is attached.
<Use of resin composition>
A first application is a filler for optical members. Specifically, the filler is filled in the gap between the front plate of the liquid crystal display and the display. Since the resin composition of the present invention has good thixotropic properties and does not cause stringing or bleeding, it can be used as a filler that requires precise work, for example, a filler for optical members. As a result, a uniform and transparent cured product can be obtained, and reflection of external light can be suppressed to improve image quality.

  In particular, the cured product of the resin composition of the present invention has a low dielectric constant and excellent transparency, so that terminal-type images such as capacitive touch panels, which have strict requirements for transparency and low dielectric constant, are required. It can be suitably used as an adhesive between members of a display device.

  Further, when a multimer type unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer is used, while maintaining the characteristics of the unsaturated carbonyl-modified conjugated diene-based hydrogenated polymer, It can be set as the liquid composition of high viscosity compared with the used resin composition. For this reason, it is excellent in maintaining the shape of the coated part, can be applied to a narrow limited area, and has a characteristic that the thickness of the coating film can be increased. In addition to the dispenser, the screen uses a squeegee. It can also be used as an adhesive utilizing printing.

  Therefore, as a second application, there is a screen printing ink that requires a heavy print portion. That is, the energy beam curable composition of the present invention has a high viscosity and good thixotropy, can prevent stringing, dripping, etc., not only maintaining the shape of the printed part, but also the ink film thickness. Since it can be enlarged, it can be suitably used as an ink for screen printing. Note that the thickness of the screen-printed coating is usually controlled by a stencil mesh. Screen printing inks using high molecular weight, multimeric unsaturated carbonyl-modified hydrogenated polybutadiene as a vehicle can provide screen printing inks with improved heat resistance and moisture resistance.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to description of a following example.

In the examples, “part” means mass basis unless otherwise specified.
<Measurement and evaluation method>
The evaluation methods employed in this example are as follows.
〔Evaluation method〕
(1) Composition viscosity (mPa · s)
The obtained resin composition was measured using a B-type viscometer (model “RB80L”, manufactured by Toki Sangyo Co., Ltd.) at a temperature of 25 ° C.
(2) Number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (Mw / Mn)
Using Tosoh columns TSK-gel SuperHM-H and TSK-gel SuperH2000, using Tosoh gel permeation under conditions where the temperature is 40 ° C. and the flow rate is 0.3 mL / min. It is a value obtained by chromatography (GPC) apparatus HLC-8220GPC and converted to standard polystyrene.
(3) Dielectric constant ε (1 MHz)
A sheet-like test piece (width 50 mm × length 50 mm × thickness 1 mm) obtained by curing the obtained resin composition was sandwiched between ^two electrodes (electrode area 9 cm ² ), and an impedance analyzer (Solartron S1- 1260), the capacitance was measured, and the dielectric constant was calculated.
(4) Curability (J / cm ² )
The composition was directly irradiated with a high-pressure mercury lamp by 1 J / cm ² (value at 365 nm), and the light irradiation amount (365 nm) at which the hardness value became constant was measured.
(5) Curing shrinkage (%)
The specific gravity of the resin composition and the specific gravity of the cured product obtained by curing the resin composition at 25 ° C. were measured and obtained from the following calculation.

Curing shrinkage (%) = (cured product specific gravity−resin composition specific gravity) / cured product specific gravity × 100
(6) Hardness value (E hardness)
Based on JIS K7312, the hardness of a sheet-like test piece (width 17 mm × length 45 mm × thickness 4 mm) obtained by curing the obtained resin composition is measured using a durometer C-type hardness meter manufactured by ASKER. did.
(7) Light transmittance (%)
Using a sheet-like test piece (width 50 mm × length 50 mm × thickness 0.3 mm) obtained by curing the obtained resin composition, the light transmittance at 400 nm was measured with a spectrophotometer (form “UV- 3100 ", manufactured by Shimadzu Corporation).
(8) Refractive index The obtained resin composition was applied onto a glass plate using an applicator bar so as to have a film thickness of 300 μm, and cured by irradiating 3.0 J / cm ² of ultraviolet light under nitrogen. To prepare a test piece. According to JIS K7105, the refractive index at 25 ° C. of the test piece was measured using an Abbe refractometer (model “DR-M2”, manufactured by Atago Co., Ltd.).
(9) Heat resistance A test piece (width 50 mm × length 70 mm × thickness 1 mm) sandwiched between glass plates obtained by curing the obtained resin composition was heated in an oven at 100 ° C. for 250 hours. . The discoloration after heating was visually confirmed and evaluated in the following three stages. A glass plate having a thickness of 3 mm was used.

◯: No discoloration was observed Δ: Slight discoloration ×: Large discoloration (10) Light resistance Test piece sandwiched between glass plates obtained by curing the obtained resin composition (width 50 mm × length 70 mm × thickness 1 mm) was irradiated with light at 200 MJ / m ² using a metering weather meter (type “M6T”, manufactured by Suga Test Instruments Co., Ltd., irradiation intensity 0.5 kW / m ² ). The discoloration after irradiation was visually confirmed and evaluated in the following three stages. A glass plate having a thickness of 3 mm was used.

○: No discoloration Δ: Slight discoloration ×: Large discoloration (11) Moisture resistance Sheet-like specimen obtained by curing the obtained resin composition (width 50 mm × length 70 mm × thickness) 1 mm) was held in a thermo-hygrostat (temperature 85 ° C., humidity 85% RH) for 100 hours, and then the turbidity of the sheet was visually confirmed and evaluated in the following three stages.

○: No turbidity △: Slightly turbid ×: Turbidity (12) Removability (repairability)
A test piece (width 50 mm × length 70 mm × thickness 0.3 mm) sandwiched between glass plates obtained by curing the obtained resin composition was prepared, and the sheet-like cured product was peeled from the glass plate. The state of time was evaluated in the following three stages. A glass plate having a thickness of 3 mm was used.

○: The cured sheet is not damaged and can be easily peeled. Δ: Although a little force is required, the cured sheet is not damaged and can be peeled. ×: The cured sheet is damaged or cannot be peeled (13) Prepare a test piece (width 50 mm × length 70 mm × thickness 0.3 mm) in a state sandwiched between glass plates obtained by curing the obtained resin composition, and place a 200 g steel ball on the test piece. The height at which the glass plate on the top surface was damaged when dropped was determined and evaluated in the following four stages. A glass plate having a thickness of 3 mm was used. In addition, the hardened | cured material obtained by making 10J / cm2 light irradiation with a high pressure mercury lamp hardened was used as the test piece.
◎: 500 mm or more ○: 300 mm or more and less than 500 mm Δ: 200 mm or more and less than 300 mm x: less than 200 mm <Synthesis of unsaturated carbonyl-modified polymer>
(1) Single unit acryloyl-modified polybutadiene (hydrogenated type)
Urethane catalyst dibutyltin diversate 0.4 g, polymerization inhibitor ADEKA Adeka Stub AO-60 0.4 g, (a-1), Nippon Soda Co., Ltd. both-end hydroxylated polybutadiene "GI-3000" 800 g (number average molecular weight 3000, iodine value 21 or less) was heated to 77 ° C. with stirring under bubbling. By charging 57 g of 2-acryloyloxyethyl isocyanate (manufactured by Showa Denko KK, product number Karenz AOI) (corresponding to 1.0 equivalent with respect to the hydroxyl group contained in GI-3000) and reacting at 80 ° C. for 120 minutes, A single acryloyl-modified hydrogenated polybutadiene was obtained. The number average molecular weight of the obtained unit type acryloyl-modified hydrogenated polybutadiene was 5,500.
(2) Multimeric acryloyl-modified polybutadiene (hydrogenated type)
Urethane catalyst dibutyltin diversate 0.4 g, polymerization inhibitor ADEKA Adeka Stub AO-60 0.4 g, (a-1), Nippon Soda Co., Ltd. both-end hydroxylated polybutadiene "GI-3000" 800 g (number average molecular weight 3000, iodine value 21 or less) was heated to 77 ° C. with stirring under bubbling. Next, 23 g of isophorone diisocyanate (IPDI) (corresponding to 0.5 equivalent to the hydroxyl group contained in GI-3000) is added dropwise at a rate of 1 mL / min, and the reaction is carried out by maintaining at 80 ° C. for 1 hour after completion of the addition. Thus, a multimeric polybutadiene polyol was obtained. Subsequently, 28 g of 2-acryloyloxyethyl isocyanate (product number Karenz AOI, manufactured by Showa Denko KK) of 1.0 equivalent (corresponding to 0.5 equivalent of the remaining hydroxyl group of GI-3000) with respect to the multimeric polybutadiene polyol was charged. The reaction was carried out at 80 ° C. for 120 minutes to obtain multimeric acryloyl-modified hydrogenated butadiene. The number-average molecular weight of the obtained multimeric acryloyl-modified hydrogenated butadiene was 9,000.
(3) Multimeric acryloyl-modified polybutadiene (non-hydrogenated type)
The same procedure as in (2) above except that instead of both-end hydroxylated hydrogenated polybutadiene "GI-3000", both-end hydroxylated polybutadiene "G-3000" (number average molecular weight 3000) manufactured by Nippon Soda Co., Ltd. was used. . However, the amount of isophorone diisocyanate (IPDI) corresponding to 0.5 equivalent to the hydroxyl group contained in G-3000 is 25 g, and 2-acryloyl corresponding to 0.5 equivalent of the remaining hydroxyl group of G-3000. The amount of oxyethyl isocyanate (product number Karenz AOI) is 32 g. The number-average molecular weight of the obtained multimeric acryloyl-modified polybutadiene was 11,000.
(4) Multimeric acryloyl-modified polyether (multimeric Ac-modified polyether)
Polypropylene glycol (Asahi Glass Co., Ltd.) having a number average molecular weight Mn of 15000 (molecular weight distribution (Mw / Mn) = 1.06) as a polyether polyol in a reactor equipped with a thermometer, a cooler, a gas introduction tube, and a stirrer (Product No. Preminol 4015) was charged with 2000 g, methoquinone 0.15 g, and dibutyltin dilaurate 0.15 g, and the mixture was heated to 70 ° C. while stirring. Next, as a connecting compound L, isophorone diisocyanate (IPDI) (manufactured by Sumika Bayer Urethane Co., Ltd.) is used in an amount of 15 g that is 0.50 equivalent to 1 equivalent of hydroxyl group in the polyether polyol. Then, it was dropped at a dropping rate of 1 mL / min. After completion of the dropwise addition, the reaction was terminated by maintaining at 70 ° C. for 2 hours to obtain a multimeric polyether polyol in which the connecting portion is a urethane bond. Subsequently, an acryloyl compound is added to 1 equivalent of the hydroxyl group in the multimeric polyether polyol (corresponding to the remaining 0.50 equivalent of hydroxyl group of the polyether polyol), and the reaction is maintained at 70 ° C. for 2 hours. As a result, a multimerized acryloyl-modified polyether was obtained.

The isocyanate reaction rate of the obtained multimeric acryloyl-modified polyether obtained by the back titration method was 99%. The viscosity at 25 ° C. was 210 Pa · s. Furthermore, the number average molecular weight (Mn) by GPC measurement was 37000.
<Ultraviolet curable resin composition No. Preparation and Evaluation of 1-6>
As the unsaturated carbonyl-modified polymer, the above-prepared multimeric acryloyl-modified polyether, simple acryloyl-modified polybutadiene (hydrogenated), multimeric acryloyl-modified polybutadiene (hydrogenated), or multimeric acryloyl-modified polybutadiene (non-hydrogenated) Type), a polymerizable component, another resin (polymer), and an additive are added at a ratio shown in Table 1, and a photopolymerization initiator (manufactured by Ciba Specialty Chemicals, product number Irgacure 184D (1-hydroxy-) is added. Corresponding to cyclohexyl-phenyl-ketone))) 1 part by weight is mixed to obtain UV curable resin composition No. 1-6 were prepared. About the obtained ultraviolet curable resin composition, the viscosity and sclerosis | hardenability were measured and evaluated based on the said measurement evaluation method. Next, each composition was dropped on a glass plate having a predetermined size in which silicone spacers having a predetermined thickness were arranged on four sides, and filled into the glass plate. Next, a glass plate of the same size was put on the top. Next, it is cured by irradiation with ³ J / cm ² light with a high-pressure mercury lamp, and the cured product layer of the composition is peeled from the test piece having a laminated structure of glass plate / cured product layer / glass plate or a glass plate. Thus, a sheet-like test piece was prepared. Based on the above evaluation and measurement methods, the test specimens were evaluated for cure shrinkage, hardness value, light transmittance, heat resistance, light resistance, moisture resistance, removability (repair property), impact resistance, and refractive index. did. The evaluation results are shown in Table 1.

The polymerizable components, other non-reactive resins, and additives used are as follows.
Isobornyl acrylate (IB-A) (Tg = 94 ° C.) (manufactured by Nippon Shokubai)
Tridecyl acrylate (Tg: −55 ° C.) (SAR489D from SARTOMER)
-2-hydroxypropyl acrylate (Tg: -7 ° C) (Nippon Shokubai Co., Ltd.)
Rosin ester resin 2: Rosin ester “KE-311” (trade name) (acid value 2-10) of Arakawa Chemical Industries, Ltd.
HV-35: polyisobutene manufactured by Nippon Mining & Energy Corporation, hydrogenated polybutadiene: “BI-2000” manufactured by Nippon Soda Co., Ltd. (number average molecular weight 2100, iodine value 21 or less)
Non-hydrogenated polybutadiene 1: “B-2000” (number average molecular weight 2100) of Nippon Soda Co., Ltd.
Non-hydrogenated polybutadiene 2: “B-1000” (number average molecular weight 1100) of Nippon Soda Co., Ltd.
Non-hydrogenated polybutadiene 3: EVONIK's “POLYVEST (registered trademark) 110” (liquid polybutadiene)
Pentaerythritol tetrakis (3-mercaptobutyrate) (PE-1) (manufactured by Showa Denko)
<Ultraviolet curable resin composition No. 1-6: Comparison of each composition>

Ｎｏ．４とＮｏ．２、３との比較から、ポリエーテル系ポリマーよりも共役ジエン系水添ポリマーを用いる方は誘電率が低くなることがわかる。
また、共役ジエン系水添ポリマーを用いる方が耐久性に優れることが分かる。
＜紫外性硬化型組成物Ｎｏ．１−３：アクリロイル変性水素化ポリブタジエンにおける親水基含有モノマーの効果、及び多量体化の効果＞
Ｎｏ．１−３の耐湿性については、親水基含有モノマーである２−ヒドロキシプロピルアクリレートを含有させることで改善できているが、２−ヒドロキシプロピルアクリレートの含有量増大により誘電率が増大する傾向にある。

No. 4 and no. From comparison with 2 and 3, it can be seen that the dielectric constant is lower when the conjugated diene hydrogenated polymer is used than when the polyether polymer is used.
Moreover, it turns out that the direction using a conjugated diene type hydrogenated polymer is excellent in durability.
<Ultraviolet curable composition No. 1-3: Effect of hydrophilic group-containing monomer and effect of multimerization in acryloyl-modified hydrogenated polybutadiene>
No. Although the moisture resistance of 1-3 can be improved by adding 2-hydroxypropyl acrylate, which is a hydrophilic group-containing monomer, the dielectric constant tends to increase due to an increase in the content of 2-hydroxypropyl acrylate.

No. using a multimeric acryloyl-modified hydrogenated polybutadiene. In Nos. 2 and 3, since the hardness can be lowered to the same level as that of the acryloyl-modified polyether, it is possible to obtain a cured product that also satisfies impact absorption. Therefore, by using the multimer-type acryloyl-modified hydrogenated polybutadiene, it is possible to satisfy a low dielectric constant, an excellent durability such as a moisture resistance, and a shock absorbing property.
<Ultraviolet curable composition No. 3, 5, 6: Effect of hydrogenation in acryloyl-modified polybutadiene>
No. No. 3 is obtained by hydrogenating the polybutadiene part. 5 and 6 are those in which the polybutadiene portion is not hydrogenated. Although it was slightly unhydrogenated, the dielectric constant tended to increase.

  No. Since 3, 5, and 6 all contain 2-hydroxypropyl acrylate as a polymerizable component, the moisture resistance, light resistance, and heat resistance at the initial stage (short time) could be satisfied. The long-term (long-time) moisture resistance, light resistance, and heat resistance were satisfied because the polybutadiene portion was hydrogenated. It was 3 people. From these results, it was found that the durability can be greatly improved by hydrogenating the conjugated diene polymer.

  In addition, No. 3, 5, and 6 are cases where a conjugated diene polymer (hydrogenated polybutadiene or non-hydrogenated polybutadiene) is used as the non-reactive resin. Although data are not shown, the dielectric constant tended to decrease compared to the case where P-1000 (polypropylene glycol) was used.

  Since the energy ray curable resin composition of the present invention provides a cured product having a low dielectric constant and excellent moisture resistance and durability, it is filled between the transparent electrode layer and the transparent member like a touch panel. It is suitable as a filler and an adhesive, and can also be suitably used as a filler and an adhesive between other optical members.

Claims (8)

(A) a conjugated diene polymer having two or more α, β-unsaturated carbonyl groups and an iodine value of 100 or less;
(B) An energy beam curable resin composition containing a photopolymerization initiator. In the (A) conjugated diene polymer, a polyol (a-1) having a number average molecular weight of 500 to 40,000 is linked through one kind of bond selected from the group consisting of a urethane bond, an ester bond, and an ether bond. 2. The energy ray-curable resin composition according to claim 1, which is a multimeric polymer and includes a multimeric conjugated diene-based polymer in which a molecular chain terminal of the multimeric polymer is α, β unsaturated carbonyl-modified. The multimeric conjugated diene polymer includes at least one selected from the group consisting of a polyol (a-1) having two or more hydroxyl groups at the terminal, an isocyanate group, a carboxyl group, a halogenated carbonyl group, an epoxy ring, and a hydroxyl group. The energy ray-curable resin composition according to claim 2, wherein the end of the molecular chain of the reaction product with the linking compound L having two or more is modified with α, β-unsaturated carbonyl. The energy beam curable resin composition according to claim 1, wherein the (A) conjugated diene polymer has a butadiene skeleton. Furthermore, (C) Hydrophilic group containing (meth) acrylate type compound is contained, The energy-beam curable resin composition of any one of Claims 1-4. Furthermore, (E) The thixotropy imparting agent is contained, The energy-beam curable resin composition of any one of Claims 1-5. Hardened | cured material obtained by hardening | curing the energy-beam curable resin composition of any one of Claims 1-6 by ultraviolet irradiation. A display device comprising the cured product according to claim 7.