TWI557197B - Resin composition for ultraviolet-curable adhesive and adhesive - Google Patents

Description

Resin composition for ultraviolet curing adhesive and adhesive

The present invention relates to a resin composition for an ultraviolet curable adhesive and an adhesive which are excellent in polymerizability, adhesion to a substrate, and water resistance.

In an optical related product typified by a touch panel or a liquid crystal display, many optical members having various kinds of materials or shapes are used as they are highly functionalized.

In the bonding of the optical member as described above, an adhesive has been used since the past, but the industry has an adhesive which has excellent adhesion without depending on the material or shape of the part.

Further, in the production site of the above optical related products, in recent years, the productivity improvement of the final product has become a major issue. One of the reasons is that since the previously used adhesive usually contains a solvent such as a solvent or water, the step of removing the solvent contained in the adhesive after applying the adhesive to the surface of the substrate or the like requires a large amount of time, thereby reducing The production efficiency of the final product.

An ultraviolet curable adhesive is known as an adhesive which can improve the production efficiency of the above products. The ultraviolet curable adhesive generally does not contain a solvent such as a solvent or water, and is therefore characterized in that it is not necessary to remove these solvents when forming the adhesive layer.

An adhesive which can improve the production efficiency of the final product as compared with the prior art is, for example, an adhesive composition comprising a high molecular weight body of 5 parts by mass or more and 200 parts per 100 parts of the monomer having an unsaturated double bond. Below the part by mass, the high molecular weight body has a urethane bond The urethane bond has an unsaturated double bond at the polymer terminal and has a weight average molecular weight of 20,000 or more (for example, refer to Patent Document 1).

However, the above-mentioned adhesive composition may not exhibit sufficient adhesion depending on the material of the substrate to be used, etc., and when the optical member or the like is used under wet heat conditions, the adhesion may decrease with time. (low water resistance) problem.

Here, in the field of a solvent-based or water-based adhesive, as a method of improving the adhesion to a substrate, it is generally known that an adhesion-imparting agent (tackifier) is added to an adhesive resin. In.

However, in the case of performing polymerization in the presence of an adhesion-imparting agent in a solvent-based or water-based adhesive, it is generally known that the polymerizability of the resin is deteriorated. Therefore, when the adhesion-imparting agent is added to the ultraviolet-curable adhesive which is polymerized during the irradiation of the ultraviolet ray, it is easy to imagine that the adhesion to the substrate is improved, but the polymerizability is deteriorated. The problem of deterioration of the adhesive retention or heat resistance.

As described above, in the field of the ultraviolet curable adhesive which can improve the production efficiency, the industry has sought to satisfy the polymerizability, the adhesion to the substrate, and the water resistance. However, such a material has not been found.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-104296

An object of the present invention is to provide a resin composition for an ultraviolet curable adhesive, which comprises an excellent polymerization which does not have polymerization inhibition The excellent adhesion to the base material containing various materials or shapes does not cause excellent adhesion to the extent of peeling over time, and the adhesiveness does not decrease even when used under wet heat conditions.

In order to solve the above problems, the inventors of the present invention actively studied the types of adhesion-imparting agents.

As a result, it has been found that, in the case of using various specific adhesion-imparting agents, the composition of the (meth)acrylic urethane resin and the (meth)acrylic monomer is not obtained. A resin composition for an ultraviolet curable adhesive which satisfies all of the polymerizability, the adhesion to the substrate, and the water resistance.

In other words, the present invention provides a resin composition for an ultraviolet curable adhesive, and an adhesive obtained by using the same, the resin composition for an ultraviolet curable adhesive comprising: a polyol (a), a polyisocyanate (polyisocyanate) (b) and a (meth)acrylic resin (a) obtained by reacting a (meth)acrylic compound (c) having a hydroxyl group (a) (A) a (meth)acrylic monomer (B), a photopolymerization initiator (C), and an adhesion-imparting agent (D); and the resin composition for an ultraviolet-curable adhesive is characterized by the above The adhesion-imparting agent (D) is selected from the group consisting of styrene, α-methyl styrene, vinyl toluene, indene, and isopropenyl toluene. One or more unsaturated aromatic compounds (d-1) in the group formed, and selected from the group consisting of isobutylene, butadiene, isoprene, and pentadiene It is obtained by reacting one or more kinds of unsaturated aliphatic compounds (d-2) in a group consisting of (piperylene) and dicyclopentadiene.

The resin composition for an ultraviolet curable adhesive of the present invention can provide an adhesive excellent in polymerizability, adhesion to a substrate, and water resistance by using the above specific tackifier. Further, the resin composition for an ultraviolet curable adhesive according to the present invention has excellent polymerizability, and is excellent in holding power, and can easily produce an adhesive by ultraviolet irradiation. Therefore, the adhesive obtained by using the resin composition for ultraviolet curable adhesives of the present invention can be suitably used as an adhesive used in optical members.

First, the (meth)acrylic urethane resin (A) used in the present invention will be described.

Examples of the above polyol (a) include polyester polyols, polyether polyols, polycarbonate polyols, polyacrylic polyols, polybutadiene polyols, polyolefin polyols, hydrogenated polyolefin polyols, and the like. The polyols may be used singly or in combination of two or more. Among them, the excellent adhesion and retention can be further improved, and the durability of the adhesive film can be further improved, and in particular, from the viewpoint of water resistance, a polyether polyol or a polycarbonate polyol is preferably used.

Examples of the polyether polyol which can be used in the above polyol (a) include alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide. One or more kinds of oxides and compounds having two or more active hydrogens are added a polymerized product, or a polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran, a modified polytetramethylene glycol obtained by copolymerizing tetrahydrofuran with an alkyl-substituted tetrahydrofuran, Or a modified polytetramethylene glycol obtained by copolymerizing neopentyl glycol and tetrahydrofuran.

Examples of the compound having two or more active hydrogens include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propylene glycol, 1,3-propanediol, dipropylene glycol, and tripropylene glycol. 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,5-hexanediol, 1, 6-hexanediol, 2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11- Undecanediol, 1,12-dodecanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, 3- Methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, 2-ethyl-1,3-propanediol, 3- Methyl-1,5-pentanediol, hydroquinone, resorcin, bisphenol A, bisphenol F, 4,4'-bisphenol (4,4'-bisphenol) a relatively low molecular weight dihydroxy compound; or 1,2-cyclobutanediol, 1,3-cyclopentanediol, 1,4-cyclohexanediol, cycloheptanediol, Cyclooctanediol, 1,4-cyclohexanedimethanol, hydroxypropylcyclohexanol, tricyclo[5,2,1,0,2,6]decane-dimethanol, bicyclo[4,3,0 ]-nonanediol, two rings Glycol, tricyclo[5,3,1,1]dodecanediol, bicyclo[4,3,0]decane dimethanol, tricyclo[5,3,1,1]dodecane-diethanol Hydroxypropyltricyclo[5,3,1,1]dodecanol, spiro[3,4]octanediol, butylcyclohexanediol, 1,1'-dicyclohexylenediol, ring An alicyclic polyol such as hexanetriol, hydrogenated bisphenol A or 1,3-adamantanediol; polyethylene glycol, polypropylene a polyether polyol such as a diol or a polytetramethylene glycol; or a polyester polyol such as polyhexamethylene adipate, polyhexamethylene succinate or polycaprolactone; glycerin, Glycerin, trimethylolpropane, bis(trimethylolpropane), tris(trimethylolpropane), 1,2,6-hexanetriol, triethanolamine, triisopropanolamine, pentaerythritol, dipentaerythritol, Sorbitol, sucrose, ethylenediamine, N-ethyldiethylenetriamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,2-di Aminobutane, 1,3-diaminobutane, 1,4-diaminobutane, diethylenetriamine, phosphoric acid, acid phosphate, and the like.

Among these compounds, an aliphatic polyether polyol is more preferably used from the viewpoint of imparting good adhesive properties, and a polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran is particularly preferred.

The polycarbonate polyol which can be used for the above-mentioned polyol (a) is, for example, obtained by reacting a carbonate and/or phosgene with the compound (a-1) having two or more active hydrogens. Compound.

Examples of the above carbonates include methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclic carbonates, and diphenyl carbonate.

Further, as the polyol (a), another active hydrogen-containing chain extender may be used in combination with the above-described polyester polyol, polyether polyol, polycarbonate polyol, polyacryl polyol, and the like. .

Examples of the other active hydrogen-containing chain extender include ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 2,3-butanediol, and 3- Methyl-1,5-pentanediol, 1,6-hexanediol, 3,3'-dimethylol heptane, 1,4-cyclohexanedimethanol, neopentyl glycol, 3,3- Bis(hydroxymethyl)heptane, diethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, sorbitol, hydroquinone dihydroxy Polyols such as ethyl ether, ethylenediamine, propylene diamine, hexamethylenediamine, trimethylhexamethylenediamine, isophoronediamine, 4,4'-bicyclo A polyamine such as hexylmethanediamine, diaminocyclohexane, methyldiaminocyclohexane or norbornene diamine; these compounds may be used singly or in combination of two or more.

The hydroxyl value of the polyol (a) is preferably in the range of 30 mgKOH/g to 230 mgKOH/g, and more preferably in the range of 50 mgKOH/g to 230 mgKOH/g, from the viewpoint of adhesion. Further, the hydroxyl value of the above polyol (a) represents a value measured in accordance with JIS K0070.

Examples of the polyisocyanate (b) include xylylene diisocyanate, phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and naphthalene. An aromatic diisocyanate such as naphthalene diisocyanate, or hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate (cyclohexane diisocyanate) Isophorone diisocyanate), 4,4'-dicyclohexylmethane diisocyanate, diisocyanato methylcyclohexane, tetramethyl xylylene Diisocyanate or the like, such as a diisocyanate having an aliphatic or aliphatic ring structure; these compounds may be used singly or in combination of two or more. Among them, it improves adhesion, retention and From the viewpoint of high heat-resistant yellowing, it is preferred to use a diisocyanate having an aliphatic cyclic structure, more preferably 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate or cyclohexane Isocyanate, diisocyanate methylcyclohexane.

The (meth)acrylic compound (c) having a hydroxyl group is used for introducing a (meth)acrylic group into the (meth)acrylic urethane resin (A). A compound containing a hydroxyl group reactive with an isocyanate group is used. In the present invention, the "(meth)acrylic compound" means an acrylic compound and/or a methacrylic compound, and the "(meth)acrylate" means an acrylate and/or a methacrylate.

Examples of the (meth)acrylic compound having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl acrylate, and (meth)acrylic acid 3. - Hydroxybutyl ester, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl acrylate, etc., alkyl (meth)acrylate having hydroxyl group, trimethylolpropane di(meth)acrylate, pentaerythritol III A polyfunctional (meth) acrylate having a hydroxyl group such as (meth) acrylate or dipentaerythritol penta (meth) acrylate, polyethylene glycol monoacrylate or polypropylene glycol monoacrylate. Among them, from the viewpoint of easiness of obtaining raw materials, polymerizability, and adhesiveness, it is more preferred to use an alkyl acrylate having a hydroxyl group, and particularly preferably 2-hydroxyethyl acrylate or 4-hydroxybutyl acrylate. .

The method for producing the (meth)acrylic urethane resin (A) is, for example, a method in which the polyol (a) and the above-mentioned (meth)acrylic compound having a hydroxyl group are permeated without a solvent. (c) After being introduced into the reaction system, the polyisocyanate (b) is supplied, mixed and reacted, or the polyol (a) is reacted with the polyisocyanate (b) in the absence of a solvent to obtain a molecular end. The urethane prepolymer having an isocyanate group is then supplied to the (meth)acrylic compound (c) having a hydroxyl group, mixed and reacted. In any of the above methods, the above reaction is preferably carried out at a temperature of from 20 ° C to 120 ° C for about 30 minutes to 24 hours.

The production of the above (meth)acrylic urethane resin (A) can be carried out in the presence of an organic solvent or an aqueous medium. Further, instead of the organic solvent or the aqueous medium, it may be produced in the presence of a (meth)acrylic monomer (B) to be described later. Among them, when the laminate is produced, it is not necessary to remove the organic solvent or the aqueous medium, and the production step can be simplified. Therefore, from the viewpoint of solvent-free conditions or viscosity suppression in the reaction system, (meth)acrylic acid is preferred. It is carried out in the presence of a monomer (B).

The polyhydric alcohol (a), the polyisocyanate (b) and the above-mentioned (meth)acrylic compound having a hydroxyl group (c) in terms of controlling the molecular weight of the obtained (meth)acrylic urethane resin (A) The reaction between the hydroxyl group of the polyol (a) and the hydroxyl group of the (meth)acrylic compound (c) having the hydroxyl group, and the polyisocyanate (b) The equivalent ratio of the isocyanate group [the total amount of isocyanate groups/hydroxy groups] is in the range of 0.75 to 1.00, more preferably in the range of 0.79 to 0.95. Further, the reaction may be carried out in the case where the above equivalent ratio exceeds 1, but in this case, in order to achieve the purpose of deactivating the terminal isocyanate group of the (meth)acrylic urethane resin (A), it is preferred to An alcohol such as methanol is used. In this case, it is preferable that the hydroxyl group of the polyol (a), the hydroxyl group of the (meth)acrylic compound (c) having a hydroxyl group, and the hydroxyl group of the alcohol are preferably the same as the above. The equivalent ratio of the polyisocyanate groups [the total amount of isocyanate groups/hydroxy groups] is adjusted so as to be within the above range.

In addition, examples of the alcohol to be used for the purpose of deactivating the terminal isocyanate group of the (meth)acrylic urethane resin (A) include a monofunctional alcohol such as methanol, ethanol, propanol or butanol. Or a difunctional alcohol containing a primary or secondary hydroxyl group, such as 1,2-propanediol or 1,3-butanediol.

Further, when the (meth)acrylic urethane resin (A) is produced, a polymerization inhibitor, a urethanization catalyst or the like may be used as needed.

Examples of the polymerization inhibitor include 3,5-di-tert-butyl-4-hydroxytoluene, hydroquinone, methyl hydroquinone, and hydroquinone monomethyl ether (methoquinone). ), p-tert-butyl catechol methoxy phenol, 2,6-di-tert-butyl cresol, phenothiazine, tetramethylthiuram disulfide, diphenylamine, two Nitrobenzene and the like.

Examples of the urethanization catalyst include nitrogen-containing compounds such as triethylamine, triethylenediamine and N-methylmorpholine, and metal salts such as potassium acetate, zinc stearate and tin octylate, and dibutyltin laurate. Such as organometallic compounds and the like.

The (meth)acrylic urethane resin (A) obtained by the above method is a compound having a (meth)acryl fluorenyl group which is subjected to radical polymerization by light irradiation or heating. From the viewpoint of further improving the adhesion and retention, and forming an adhesive layer having good transparency, the above (A The equivalent weight of the acrylonitrile group is preferably in the range of 4,000 to 14,000, more preferably 5,000 to 8,000. Further, the equivalent weight of the above (meth)acryl fluorenyl group means the total mass of the above polyol (a), polyisocyanate (b) and (meth)acrylic compound (c) having a hydroxyl group, and is divided by the above ( The value obtained by the equivalent of the (meth) acrylonitrile group present in the methyl acrylate urethane resin (A), the unit is gram / equivalent (g / eq.).

In addition, the weight average molecular weight of the (meth)acrylic urethane resin (A) is preferably from the viewpoint of improving the balance between the excellent adhesion and the holding power and imparting good coating workability. The range of 1,000 to 50,000 is more preferably in the range of 10,000 to 25,000, and particularly preferably in the range of 12,000 to 25,000. Further, the weight average molecular weight of the (meth)acrylic urethane resin (A) is a value obtained by using gel permeation chromatography (GPC) in terms of polystyrene.

Next, the (meth)acrylic monomer (B) used in the present invention will be described.

Examples of the (meth)acrylic monomer include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, and (methyl). Butyl acrylate, isobutyl (meth)acrylate, amyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, (methyl) Isoheptyl acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate Ester, hexadecyl (meth) acrylate, 2-methyl butyl (meth) acrylate, 2-methyl amyl (meth) acrylate, 2-ethylbutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, trimethylmethyl (meth)acrylate, isotetradecyl (meth)acrylate, ( 2-methoxyethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate , 2-ethoxypropyl (meth)acrylate, 2-ethoxybutyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, (methyl) Cyclohexyl acrylate, phenoxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, ( 2-hydroxyethyl methacrylate, 3-hydroxypropyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (methyl) Acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, N-methylol (meth)acrylamide, (meth)acrylonitrile , (meth) acrylamide, dimethyl (meth) acrylamide, diethyl (meth) acrylamide, N, N-dimethylamino propyl ( Acrylamide, N,N-dimethylaminopropyl (meth) acrylamide, N,N-dimethylaminopropyl (meth) propylene amide amine methylated quaternary salt, (methyl Acetyl morphylmorpholine, isopropyl (meth) acrylamide, N-(methyl) propylene methoxyethyl hexahydrophthalimide, hydroxyethyl (meth) acrylamide , (meth)acrylic acid propyl acrylate, (meth)acrylic acid ethyl carbitol, (meth)acrylic acid trifluoromethyl methyl ester, (meth)acrylic acid 2-trifluoromethyl ethyl ester, (a) 2-acrylic acid 2-perfluoroethyl ethyl ester, 2-perfluoroethyl-2-perfluorobutyl ethyl (meth)acrylate, 2-perfluoroethyl (meth)acrylate, (meth)acrylic acid Perfluoromethyl ester, diperfluoromethyl methyl (meth)acrylate, 2-perfluoromethyl-2-perfluoroethyl ethyl (meth)acrylate, 2-perfluorohexyl (meth)acrylate Ester, 2-perfluorodecylethyl (meth)acrylate, (A) 2-acrylic acid hexadecyl ethyl acrylate, pentaerythritol tri(meth) acrylate, methoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate And (meth)acrylic acid isoamyl ester, (meth)acrylic acid ethoxy diethylene glycol, rosin epoxy acrylate, etc. These compounds may be used individually or in combination of 2 or more types.

Among these compounds, it is difficult to generate a radical by ultraviolet rays to stop the reaction, and it is more preferable to use an acrylic monomer from the viewpoint of further improving the polymerizability, and it is particularly preferable to use the viewpoint of further improving the adhesiveness. : acrylmeryl morpholine, dimethyl methacrylate, dimethylaminopropyl acrylamide, N-propylene methoxyethyl hexahydrophthalimide, butyl acrylate, 2-ethyl acrylate Hexyl ester, 2-methoxyethyl acrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, cyclohexyl acrylate, isobornyl acrylate, rosin epoxy acrylate, especially: acrylonitrile? Porphyrin, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, isobornyl acrylate, rosin epoxy acrylate.

Further, in the present invention, other vinyl monomers may be used in combination with the above (meth)acrylic monomers as long as they do not impair the effects of the present invention.

Examples of the other vinyl monomer include styrene monomer such as styrene, p-methylstyrene, ethylstyrene, propylstyrene, isopropylstyrene or p-tert-butylstyrene, and vinyl acetate. A vinyl monomer such as vinyl propionate or vinyl pivalate.

The above-mentioned (meth)acrylic urethane resin (A) is 100 parts by mass with respect to the above-mentioned (meth)acrylic urethane resin (A) from the viewpoint of having excellent adhesion and retention. The amount of the (meth)acrylic monomer (B) to be used is preferably from 30 parts by mass to 200 parts by mass, more preferably from 40 parts by mass to 150 parts by mass, particularly preferably 50 parts by mass. A range of 130 parts by mass.

Next, the photopolymerization initiator (C) used in the present invention will be described.

The photopolymerization initiator (C) generates a radical by light irradiation or heating, and initiates radicals of the (meth)acrylic urethane resin (A) or the (meth)acrylic monomer (B). polymerization.

Examples of the photopolymerization initiator include 4-phenoxydichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 1-( 4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 4-(2-hydroxyethoxy)-phenyl (2-hydroxy- 2-propyl)ketone, 2-methyl-[4-(methylthio)phenyl]-2-morpholinyl-1-propanone, 2,2-dimethoxy-2-phenylacetophenone Acetophenones; benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether and other benzoin; benzophenone, benzhydryl benzoic acid, benzhydryl benzoic acid methyl ester, 4 -Phenylbenzophenone, hydroxybenzophenone, 4-benzylidene-4'-methyldiphenyl sulfide, 3,3'-dimethyl-4-methoxybenzophenone And other benzophenones; thioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4 - thioxanthone such as diethyl thioxanthone, isopropyl thioxanthone, 2,4-diisopropyl thioxanthone; 4,4'-dimethylamino thioxanthone (alias = mazinone) , 4,4'-diethylaminobenzophenone, α-acyloxim ester Benzoin acyl (benzil), benzoyl methyl ( "Vicure 55"), 2- ethylanthraquinone (2-ethyl anthraquinone) anthraquinones like; 2,4,6- a fluorenylphosphine oxide such as benzamidine diphenylphosphine oxide ("Lucirin TPO") or bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide ("IRGACURE 819"); , 3', 4, 4'-tetrakis(tert-butylperoxycarbonyl)benzophenone ["BTTB" manufactured by Nippon Oil & Fats Co., Ltd.], acrylylated benzophenone, and the like.

Further, the adhesion and the holding force can be further improved, and the discoloration of the adhesive layer with time can be prevented, and the (meth)acrylic urethane resin, the (meth)acrylic monomer, and the adhesion described later can be further improved. From the viewpoint of imparting compatibility or polymerizability of the agent (D), the above photopolymerization initiator is preferably used: 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxyl ring Hexyl phenyl ketone, 2,4,6-trimethyl benzhydryldiphenylphosphine oxide, bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide. Among them, it is particularly preferred to use the above 2-hydroxy-2-methyl-1-phenylpropan-1-one and/or 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, which is particularly preferable. To use the two together.

Further, in the case where the above 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2,4,6-trimethylbenzimidyldiphenylphosphine oxide are used in combination, Further, from the viewpoints of compatibility or polymerization property of the (meth)acrylic urethane resin, the (meth)acrylic monomer, and the adhesion-imparting agent (D) described later in the present invention, 2 The mass ratio of -hydroxy-2-methyl-1-phenylpropan-1-one to 2,4,6-trimethylbenzimidyldiphenylphosphine oxide is preferably (2-hydroxy-2-methyl) Benzyl-1-phenylpropan-1-one) / (2,4,6-trimethylbenzimidyldiphenylphosphine oxide) = 20/80 to 80/20, particularly preferably 45/ Range of 55~65/35.

The photopolymerization initiator (C) is preferably used in an amount of 0.1 part by mass based on 100 parts by mass of the above (meth)acrylic urethane resin (A). The range of ~20 parts by mass, more preferably in the range of 0.5 parts by mass to 15 parts by mass.

Hereinafter, the adhesion-imparting agent (D) used in the present invention will be described.

In order to solve the problem of the present invention, the adhesion-imparting agent (D) must be one or more kinds of unsaturated groups selected from the group consisting of styrene, α-methylstyrene, vinyltoluene, hydrazine, and isopropenyltoluene. The aromatic compound (d-1) and one or more unsaturated aliphatic compounds (d-2) selected from the group consisting of isobutylene, butadiene, isoprene, pentadiene, and dicyclopentadiene a compound obtained by the reaction.

In particular, the adhesion-imparting agent (D) is preferably a compound obtained by reacting isopropenyltoluene with 1,3-butadiene from the viewpoint of further improving the polymerizability, the adhesion, and the water resistance.

Further, when the adhesion-imparting agent (D) is obtained, the unsaturated aromatic compound (d-1) and the unsaturated aliphatic group are more preferably obtained from the viewpoint of further improving the polymerizability, the adhesion, and the water resistance. The compound (d-2) is reacted in a range of (d-1) / (d-2) = 50 / 50 to 90/10 by mass ratio, and particularly preferably 60/40 to 80/20.

The method for producing the above-mentioned adhesion-imparting agent (D) (co-polymerization reaction) is, for example, a method in which the unsaturated aromatic compound (d-1) and the above unsaturated aliphatic compound (d-2) are used in a catalyst (d- The polymerization is carried out in the presence of 3).

Examples of the catalyst (d-3) include aluminum chloride, aluminum bromide, monoethylaluminum dichloride, titanium tetrachloride, tin tetrachloride, and boron trifluoride.

The use of the above catalyst (d-3) with respect to the total amount of the above unsaturated aromatic compound (d-1) and unsaturated aliphatic compound (d-2) The amount is preferably in the range of 0.01% by mass to 5% by mass, preferably 0.05% by mass to 3% by mass.

Further, the above copolymerization reaction is carried out at a reaction temperature of from -30 ° C to 250 ° C, more preferably from -30 ° C to 50 ° C. Further, the polymerization time is about 0.5 hours to 5 hours, but the polymerization reaction is usually completed in about 1 hour to 2 hours. The polymerization pattern can be either batchwise or continuous. In addition, multi-stage polymerization can also be performed.

In the above-mentioned copolymerization reaction, at least one selected from the group consisting of aromatic hydrocarbons, aliphatic hydrocarbons, and alicyclic hydrocarbons is preferably used in order to remove heat of reaction or to suppress high viscosity of the reaction mixture. The polymerization is carried out in a hydrocarbon solvent.

Examples of the hydrocarbon solvent include aromatic hydrocarbons such as toluene, xylene, ethylbenzene, mesylene, cumene, and cymene. An aliphatic hydrocarbon such as an alkane, hexane, heptane or octane; an alicyclic hydrocarbon such as cyclopentane, cyclohexane or methylcyclohexane; or the like.

The amount of the hydrocarbon solvent to be used is preferably such that the initial concentration of the unsaturated aromatic compound (d-1) and the unsaturated aliphatic compound (d-2) is from 10% by mass to 80% by mass.

Further, after completion of the above copolymerization reaction, it is preferred to wash the reaction system to remove the catalyst residue. The cleaning liquid is preferably an alkali aqueous solution in which potassium hydroxide, sodium hydroxide or the like is dissolved or an alcohol such as methanol.

After the completion of the washing, the unreacted monomer, the hydrocarbon solvent or the like is preferably distilled off under reduced pressure to obtain an adhesion-imparting agent (D).

The weight average molecular weight of the above-mentioned adhesion-imparting agent (D) obtained by the above method is preferably in the range of 1,000 to 2,000 from the viewpoint of further improving the polymerizability, the adhesion, and the water resistance. Further, the weight average molecular weight of the above-mentioned adhesion-imparting agent (D) is a value obtained by gel permeation chromatography (GPC) in terms of polystyrene.

In addition, the number average molecular weight of the adhesion-imparting agent (D) is preferably in the range of 500 to 1,000 from the viewpoint of further improving the polymerizability, the adhesion, and the water resistance. Further, the number average molecular weight of the above-mentioned adhesion-imparting agent (D) is a value obtained by gel permeation chromatography (GPC) in terms of polystyrene.

In addition, from the viewpoint of further improving the polymerizability, the adhesion, and the water resistance, the ratio of the weight average molecular weight to the number average molecular weight of the adhesion-imparting agent (D) is more preferably Mw/Mn = 1.00 to 2.00.

Further, from the viewpoint of further improving the adhesion and water resistance, the adhesion-imparting agent (D) preferably has a melt viscosity at 200 ° C of 30 mPa. s~70mPa. The scope of s. Further, the melt viscosity of the above-mentioned adhesion-imparting agent (D) indicates a value measured by a B-type viscometer.

Further, the softening point of the adhesion-imparting agent (D) is preferably from 70 ° C to 150 ° C, more preferably from 80 ° C to 130 ° C, and particularly preferably from 90 ° C to 105 ° C. Further, the softening point of the above-mentioned adhesion-imparting agent (D) is a value measured by the ring and ball method defined in JIS K2207.

Further, the glass transition temperature (Tg) of the adhesion-imparting agent (D) is more preferably in the range of 20 ° C to 40 ° C. Further, the glass transition temperature of the above-mentioned adhesion-imparting agent (D) is based on the dynamics of using a dynamic viscoelasticity measuring device. Value obtained by dynamic mechanical analysis (DMA). Specifically, the sample thickness is 2.0 mm, the width is 10.0 mm, the span length is 40 mm, the torsional vibration frequency is 1.0 Hz, and the generated torque is 3 gf. Cm~200gf. The DMA measurement was carried out under the conditions of cm and the temperature increase rate of 5.0 ° C / min, and the temperature at the intersection of the tangent to the glass region and the tangent to the glass transition region was calculated as the glass transition temperature in the graph of the stored elastic modulus (G')-temperature. .

From the viewpoint of further improving the polymerizability, the adhesion, and the water resistance, the amount of the adhesion-imparting agent (D) used is preferably 100 parts by mass based on 100 parts by mass of the (meth)acrylic urethane resin (A). It is used in the range of 5 parts by mass to 100 parts by mass, more preferably in the range of 8 parts by mass to 30 parts by mass.

Further, the above-mentioned adhesion-imparting agent (D) can be obtained as "FTR-6100" (manufactured by Mitsui Chemicals Co., Ltd.) as a commercial product.

Next, the resin composition for an ultraviolet curable adhesive of the present invention will be described.

The resin composition for an ultraviolet curable adhesive of the present invention can be produced, for example, by a method in which a (meth)acrylic monomer (B) is produced by separately producing a (meth)acrylic urethane resin (A). a method of mixing a photopolymerization initiator (C) and an adhesion-imparting agent (D); or producing a (meth)acrylic urethane resin in the presence of a part or all of the (meth)acrylic monomer (B) (A) A method of mixing a photoinitiator (C) and an adhesion-imparting agent (D).

Good adhesion or good handling of the adhesive solution during coating From a good point of view, the resin composition for the ultraviolet curable adhesive obtained by the above method is preferably 500 mPa. s~20,000mPa. The range of s is more preferably 1,000mPa. s~15,000mPa. The scope of s. Further, the above viscosity means a value measured by a B-type viscometer at 25 °C.

Further, the resin composition for an ultraviolet curable adhesive of the present invention may contain other additives in addition to the above compounds.

For the above other additives, for example, a light stabilizer, an antioxidant, a rust inhibitor, a thixotropic agent, a sensitizer, a polymerization inhibitor, a hardener, a hardening accelerator, a leveling agent, an adhesion promoter, a paraffin wax, and a heat stabilizer can be used. Agent, fluorescent whitening agent, foaming agent, thermoplastic resin, thermosetting resin, organic solvent, conductivity imparting agent, antistatic agent, moisture permeability improving agent, water repellent, hollow foam, water containing crystal water Compounds, flame retardants, water absorbing agents, hygroscopic agents, deodorants, foam stabilizers, defoamers, mildew inhibitors, preservatives, algaecides, anti-adhesives, anti-hydrolysis agents, organic and inorganic water-soluble Compounds, etc.

Further, the resin composition for an ultraviolet curable adhesive may be the (meth)acrylic urethane resin (A), the (meth)acrylic monomer (B), and the photopolymerization initiator (C). a composition obtained by dissolving or dispersing the above-mentioned adhesion-imparting agent (D) and the above-mentioned other additives as needed in a solvent such as an organic solvent or an aqueous medium, but dissolved in the (meth)acrylic monomer (B) Or a composition in which the (meth)acrylic urethane resin (A), the photopolymerization initiator (C), and the adhesion-imparting agent (D) are dispersed, when a laminate is bonded to a substrate, The step of removing the solvent contained in the adhesive does not need to be removed, and the production efficiency of the above laminated body can be improved, which is preferable.

Examples of the light-resistant stabilizer include a radical scavenger such as a thiol-based, thioether-based or hindered amine-based compound, and a UV absorber such as a benzophenone-based or benzoate-based compound; these compounds can be used alone. Two or more types can also be used together. Among them, from the viewpoint of maintaining excellent adhesion and retention, and further improving the compatibility with the specific (meth)acrylic monomer used in the present invention and light stability, it is preferred. A hindered amine compound is used.

Examples of the hindered amine-based compound include cyclohexane and N-butyl 2,2,6,6-tetramethyl-4-acrididineamine-2,4,6-trichloro 1,3,5. - a reaction product of a reaction product of triazine and 2-aminoethanol (trade name: Tinuvin (registered trademark) 152 (manufactured by BASF Japan), sebacic acid bis(2,2,6,6- Tetramethyl-1-(octyloxy)-4-acridinyl)ester (trade name: Tinuvin (registered trademark) 123 (manufactured by BASF)), 1,1-dimethylethylhydroperoxide a hindered amine compound having an aminoether group, such as a reaction product of an octane; N-acetamido-3-dodecyl-1-(2,2,6,6-tetramethyl-4-acridinyl) a pyrrolidine-2,5-dione (trade name: Hostavin (registered trademark) 3058 (manufactured by Clariant Japan Co., Ltd.), and the like, an N-acetyl group-based hindered amine compound; 1,2,2,6,6-pentamethyl-4-acridinyl)ester (trade name: Sanol LS765 (manufactured by BASF Japan)), {[3,5-double (1,1-two) Methyl ethyl)-4-hydroxyphenyl]methyl}butylmalonate bis(1,2,2,6,6-pentamethyl-4-acridinyl)ester (trade name: Tinuvin (registered Trademark) 144 (made by BASF Japan), dimethyl succinate and 4-hydroxy-2,2,6,6- Methyl-1-piperidine ethanol polymer (trade name: Tinuvin (registered trademark) 622LD (BASF Japan (shares) manufactured)), Malonic acid [{4-methoxyphenyl}methylene]-bis(1,2,2,6,6-pentamethyl-4-acridinyl)ester (trade name: Hostavin (registered trademark) An N-alkyl hindered amine compound of PR-31 (manufactured by Clariant Japan).

Among them, the polymerizability, the adhesion, and the water resistance can be maintained, and the compatibility with other components used in the present invention and the light stability can be further improved, and it is particularly preferable to use a hindrance having an aminoether group. Amine compound.

The light-resistant stabilizer is preferably used in an amount of 0.01 parts by mass based on 100 parts by mass of the (meth)acrylic urethane resin (A) from the viewpoint of imparting heat-resistant yellowing of the pressure-sensitive adhesive film. It is used in the range of 10 parts by mass, more preferably in the range of 0.1 part by mass to 5 parts by mass.

Examples of the antioxidant include a hindered phenol-based compound (primary antioxidant) that captures a radical generated by thermal degradation, and a phosphorus-based or sulfur-based compound (secondary antioxidant) that decomposes a peroxide generated by thermal degradation. These compounds may be used alone or in combination of two or more.

The hindered phenol-based compound is, for example, triethylene glycol-bis-[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate] (trade name: IRGANOX (registered trademark) 245 (made by BASF Japan Co., Ltd.), pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (trade name: IRGANOX (registered trademark) 1010 (BASF Japan ( ()))), octadecyl [3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate (trade name: IRGANOX (registered trademark) 1076 (Manufactured by BASF Japan) )), thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (trade name: IRGANOX (registered trademark) 1035 (BASF Japan) Manufactured)), phenylpropionic acid-3,5-bis(1,1-dimethylethyl)-4-hydroxy-C ₇ -C ₉ side chain alkyl ester (trade name: IRGANOX (registered trademark) 1135 ( BASF Japan (manufactured by Japan)), 4,6-bis(dodecylthiomethyl)-o-cresol (trade name: IRGANOX (registered trademark) 1726 (manufactured by BASF Japan), N-phenyl Reaction product of aniline with 2,4,4-trimethylpentene (trade name: IRGANOX (registered trademark) 5057 (manufactured by BASF Japan), 2-tert-butyl-6-(3-tert-butyl) -2-hydroxy-5-methylbenzyl )-4-methylphenyl acrylate (trade name: Sumilizer (registered trademark) GM (manufactured by Sumitomo Chemical Co., Ltd.), 3,9-bis[2-[3-(tert-butyl-4-hydroxy-) 5-methylphenyl)propanoxy]-1,1-dimethylethyl]2,4,8,10-tetraoxaspiro[5.5]undecane (trade name: Sumilizer ( Registered trademark) GA-80 (manufactured by Sumitomo Chemical Co., Ltd.), 2,6-di-tert-butyl-4-methylphenol (trade name: Nocrac 200 (manufactured by Ouchi Emerging Chemical Industry Co., Ltd.)), 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (trade name: Nocrac NS-6 (made by Ouchi Emerging Chemical Industry Co., Ltd.)), 2,5-di-union Pentohydroquinone (trade name: Nocrac DAH (manufactured by Ouchi Shinko Chemical Co., Ltd.), etc.

Examples of the phosphorus-based compound include triphenylphosphine, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite, and triphenyl phosphite. Tridecyl phenyl phosphite, tris(2,4-dibutylphenyl) phosphite, tris(2,4-dibutyl-5-methylphenyl) phosphite, tris[3] -T-butyl-4-(3-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl]ester, tridecyl phosphite, octyl diphenyl phosphite Ester, bis(indenyl)monophenyl phosphite, ditridecylpentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, bis(2,4-dibutylphenyl) Pentaerythritol diphosphite, double (2,6-Dibutyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tributylphenyl)pentaerythritol diphosphite, bis(2,4-diiso) Propyl phenyl) pentaerythritol diphosphite, tetrakis(tridecyl) isopropylidene diphenol diphosphite, tetrakis(tridecyl)-4,4'-n-butylene bis(2- Butyl-5-methylphenol) diphosphite, hexatridecyl-1,1,3-tris(2-methyl-4-hydroxy-5-butylphenyl)butane triphosphorous acid Ester, tetrakis(2,4-dibutylphenyl)biphenyldiphosphinate, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (9,10 -dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), 2,2'-methylenebis(4,6-butylphenyl)-2-ethylhexylphosphite, 2,2'- Methylene bis(4,6-butylphenyl)-octadecyl phosphite, 2,2'-ethylenebis(4,6-dibutylphenyl)fluorophosphite, three ( 2-[(2,4,8,10-tetrabutyldibenzo[d,f][1,3,2]dioxaphosphocycloheptan-6-yl)oxy]ethyl)amine ( Tris(2-[(2,4,8,10-tetrakisbutyldibenzo[d,f][1,3,2]dioxaphos phepin-6-yl)oxy]ethyl)amine), 2-ethyl-2-butyl a phosphite of propylene glycol and 2,4,6-tributylphenol.

Examples of the above sulfur-based compound include didodecyl-3,3'-thiopropionate and dilauryl-3,3'-thiodipropane. Acid ester (dilauryl-3,3'-thiodipropionate), dilaurylthiodithiosulfate, ditridecyl-3,3'-thiodipropionate (ditridecyl-3,3'- Thiodipropionate), dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate (distearyl-3) , 3'-thiodipropionate), tetrakis-methylene-3-laurylthiopropionate methane, Stearyl aryl-3,3'-methyl-3,3'-thiodipropionate, laurylstearyl-3,3 '-Luryl stearyl-3,3'-thiodipropionate, bis[2-methyl-4-(3-n-alkylthiopropoxy)-5-tert-butylphenyl] Sulfide (bis[2-methyl-4-(3-n-alkylthiopropylyl)-5-t-butylphenyl]sulfide), β-lauryl thiopropionate, 2-mercaptobenzimidazole (2-mercaptobenzimidazole), 2-mercapto-5-methylbenzimidazole, di(octadecyl)-3,3'-thiodipropionate (dioctadecyl-3) , 3'-thiodipropionate) and so on.

Among these compounds, in view of maintaining polymerizability, adhesion, and water resistance, and further improving compatibility with other components used in the present invention and heat yellowing resistance, it is preferred to use a phosphorus compound. It is preferred to use triphenylphosphine, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite, pentaerythritol tetra [3-(3,5- Di-tert-butyl-4-hydroxyphenyl)propionate.

The antioxidant is preferably used in an amount of 0.01 parts by mass based on 100 parts by mass of the (meth)acrylic urethane resin (A) from the viewpoint of imparting good heat-resistant yellowing resistance to the adhesive film. It is used in the range of 10 parts by mass, more preferably in the range of 0.1 part by mass to 5 parts by mass.

Examples of the rust inhibitor include a triazole compound, an organic carboxylic acid amine salt, an nitrite amine salt, an ammonium phosphate salt, an amine carbonate, and a heterocyclic amine. among them, The polymerizability, the adhesion, and the water resistance can be maintained, and the compatibility with the other components used in the present invention and the rust preventive property can be further improved without impairing the light stability and the heat yellowing resistance. To use a triazole compound.

Examples of the triazole-based compound include 1-[bis(2-ethylhexyl)aminomethyl]benzotriazole, methylbenzotriazole, dimethylbenzotriazole, and ethylbenzotriazole. , ethylmethylbenzotriazole, diethylbenzotriazole, unsubstituted benzotriazole, 5-methyl-1H-benzotriazole, N,N-bis(2-ethylhexyl) - (4 or 5)-methyl-1H-benzotriazole-1-methylamine, a triazole compound represented by the following formula (1), and the like.

(wherein R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, and 7 to 10 carbon atoms; 13 aralkyl, 6 to 10 aryl, hydroxy.)

As the triazole compound represented by the above formula (1), N,N-bis(2-ethylhexyl)-[(1,2,4-triazol-1-yl)methyl]amine or the like is suitably used.

It does not reduce the adhesiveness and gives good rust prevention. In the case of 100 parts by mass of the above (meth)acrylic urethane resin (A), the amount of the above rust inhibitor is preferably used in the range of 0.001 part by mass to 5 parts by mass, more preferably 0.01 part by mass. The range of ~2 parts by mass.

Examples of the sensitizer include biphenyl, 1,4-dimethylnaphthalene, 9-fluorenone, fluorene, and phenanthrene. Triphenylene, anthracene, 9,10-diphenyl anthracene, 9,10-dimethoxy anthracene, 9,10- 9,10-diethoxy anthracene, 9,10-dipropoxy anthracene, 9,10-dibutoxy anthracene, Benzophenone, 4,4'-dimethoxy benzophenone, acetophenone, 4-methoxy acetophone, Benzaldehyde and the like.

Examples of the curing agent include an adduct derived from toluene diisocyanate or hexamethylene diisocyanate, and a polyisocyanate compound represented by an isocyanurate or the like, or a polyfunctional epoxy compound or a melamine compound. , metal chelate and the like.

The resin composition for an ultraviolet curable adhesive of the present invention can be cured by irradiation with an energy ray such as ultraviolet rays.

The method of curing the resin composition for an ultraviolet curable adhesive of the present invention can be irradiated with a predetermined ultraviolet ray by using a known ultraviolet light irradiation device such as a xenon lamp, a krypton-mercury lamp, a metal halide lamp, a high-pressure mercury lamp or a low-pressure mercury lamp. And make it harden.

Irradiating the ultraviolet rays is preferably ^{0.05J / cm 2 ~ 5J / cm} 2, more preferably ^{0.1J / cm 2 ~ 3J / cm} 2, particularly preferably in the range of ^{0.3J / cm 2 ~ 1.5J / cm} 2 of. Further, the amount of ultraviolet irradiation was measured using a UV tester UVR-N1 (manufactured by GS Yuasa Co., Ltd.) in a wavelength region of 300 nm to 390 nm.

In addition, when the resin composition for an ultraviolet curable adhesive of the present invention contains the above-mentioned other additives, it may be further accelerated by heating at about 40 to 80 ° C after the irradiation of the ultraviolet rays as needed.

The adhesive containing the resin composition for an ultraviolet curable adhesive of the present invention can be suitably used as an adhesive for an optical member because it has excellent adhesion and holding power.

A preferred embodiment of the adhesive comprising the resin composition for an ultraviolet curable adhesive of the present invention is, for example, an adhesive for bonding the upper and lower sheets used in a membrane sheet keyboard, or a frame fixing of a liquid crystal display. Adhesives used, adhesives used in various labels.

Further, the thickness of the adhesive layer in the case where the adhesive of the present invention is used in various applications varies depending on the use, and can be appropriately selected from the range of approximately 0.1 μm to 500 μm.

[Example]

Hereinafter, the present invention will be described in more detail by way of examples.

[Synthesis Example 1]

<Synthesis of (meth)acrylic urethane resin (A-1)>

To the counter with a mixer, reflux cooling tube, nitrogen inlet tube, thermometer In the container, 465.9 parts by mass of polytetramethylene glycol (hydroxyl value 112 mg KOH/g), 9.6 parts by mass of 2-hydroxyethyl acrylate, and 1.7 parts by mass of 2,6-di-tert-butyl-cresol were added. 0.3 parts by mass of p-methoxyphenol. After the temperature in the reaction vessel was raised to 40 ° C, 101.5 parts by mass of isophorone diisocyanate was added. Further, 0.06 parts by mass of dioctyltin diruthenate was added, and the temperature was raised to 80 ° C over 1 hour. Thereafter, the mixture was kept at 80 ° C for 12 hours, and it was confirmed that all the isocyanate groups disappeared, and then cooled to obtain a (meth)acrylic urethane resin (A-1). The obtained (meth)acrylic urethane resin (A-1) had an acrylonitrile group having an equivalent weight of 7,000 and a weight average molecular weight of 18,000.

[Example 1]

100 parts by mass of (meth)acrylic urethane resin (A-1) obtained in Synthesis Example 1 and butyl acrylate 40 were added to a vessel equipped with a stirrer, a reflux cooling tube, and a thermometer at a temperature of 80 ° C in the vessel. Parts by mass, 30 parts by mass of acryloylmorpholine, FTR-6100 (manufactured by Mitsui Chemicals Co., Ltd., weight average molecular weight: 1,154, number average molecular weight: 612, melt viscosity at 200 ° C: 60 mPa.s), 17 parts, stirring Until it is even. Then, it was cooled to room temperature, and 4 parts by mass of 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2,4,6-trimethoxybenzimidyl diphenyl group were sequentially added under stirring. 3 parts by mass of phosphine oxide was stirred until it reached uniformity. Then, the mixture was filtered through a 200-mesh wire mesh to obtain a resin composition for an ultraviolet curable adhesive.

[Example 2]

In addition to changing the amount of photopolymerization initiator used to be as shown in Table 1 Further, a resin composition for an ultraviolet curable adhesive was obtained in the same manner as in Example 1.

[Comparative Example 1 to Comparative Example 6]

A resin composition for an ultraviolet curable adhesive was obtained in the same manner as in Example 1 except that the type of the adhesion-imparting agent to be used was changed to that shown in Table 1.

[Method for Measuring Weight Average Molecular Weight and Number Average Molecular Weight]

The weight average molecular weight and the number average molecular weight of the (meth)acrylic urethane resin (A-1) and FTR-6100 used in the examples were measured by a gel permeation chromatography (GPC) method under the following conditions.

Measuring device: High-speed GPC device ("HLC-8220GPC" manufactured by Tosoh Corporation)

Pipe column: The following pipe strings manufactured by Tosoh Corporation are connected in series for use.

"TSK gel G5000" (7.8mmI.D.×30cm) × 1

"TSK gel G4000" (7.8mmI.D.×30cm) × 1

"TSK gel G3000" (7.8mmI.D.×30cm) × 1

"TSK gel G2000" (7.8mmI.D.×30cm) × 1

Detector: RI (differential refractometer)

Column temperature: 40 ° C

Dissolved solution: tetrahydrofuran (THF)

Flow rate: 1.0mL/min

Injection amount: 100 μL (sample concentration 0.4% by mass in tetrahydrofuran solution)

Standard sample: The calibration curve was prepared using the following standard polystyrene.

(standard polystyrene)

"TSK gel standard polystyrene A-500" manufactured by Tosoh Corporation

"TSK gel standard polystyrene A-1000" manufactured by Tosoh Corporation

"TSK gel standard polystyrene A-2500" manufactured by Tosoh Corporation

"TSK gel standard polystyrene A-5000" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-1" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-2" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-4" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-10" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-20" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-40" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-80" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-128" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-288" manufactured by Tosoh Corporation

"TSK gel standard polystyrene F-550" manufactured by Tosoh Corporation

[How to make adhesive film]

The resin composition for the ultraviolet curable adhesive obtained in the examples and the comparative examples was applied to the surface of the polyethylene terephthalate film (PET75) having a thickness of 75 μm so that the film thickness after the UV irradiation was 22 μm. On the coated surface, a polyethylene terephthalate film (released PET 50) having a thickness of 50 μm which was subjected to release treatment from the surface different from the above was bonded.

Next, ultraviolet rays were irradiated from the upper side of the above-mentioned release PET 50 using a UV irradiation device to prepare an adhesive film laminated via two polyethylene terephthalate films. The irradiation of the ultraviolet rays is carried out under the condition that the integrated light amount of the wavelength of 300 nm to 390 nm after passing through the release PET 50 is 1 J/cm ² .

[Method for evaluating polymerization property]

The polymerizability was evaluated using the gel fraction of the adhesive. The term "polymerizability" as used herein refers to the molecular weight of the polymer formed during UV irradiation, and an adhesive having a large value is likely to form a crosslinked structure and exhibit a high gel fraction. Therefore, in the evaluation of the polymerizability, in order to make it easy to determine, the types of the (meth)acrylic urethane resin and the (meth)acrylic monomer are fixed, and the crosslinking density is uniform, and only the type of the adhesion-imparting agent is changed. The value of the gel fraction was measured, and the evaluation of the polymerizability was performed.

Specifically, the adhesive film was cut into a size of 40 mm × 50 mm to obtain a test piece. Next, the mass (G1) before the toluene immersion of the test piece from which the release PET was peeled off and the mass (G0) of the PET 75 of the above-mentioned size were measured, and immersed in a toluene solution at room temperature for 24 hours. Then, the toluene-insoluble component of the immersed test piece was separated by filtration through a 300-mesh wire mesh, and the mass (G2) of the residual component after drying at 105 ° C for 1 hour was measured, according to the following formula (2). To determine the gel fraction.

Gel fraction (%) = [(G2) - (G0) / (G1) - (G0)] × 100 (2)

Further, those having a gel fraction of 40% or more were evaluated as "?", those less than 40% and 30% or more were evaluated as "○", and those having less than 30% were evaluated as "X".

Further, the adhesion imparting agent was inferior in compatibility with the (meth)acrylic acid urethane, and the evaluation by the evaluator was not evaluated as "-".

[Method for Evaluating Adhesion of Substrate]

The evaluation of the adhesion of the substrate was evaluated by the adhesion.

Specifically, a release PET 50 constituting the above-mentioned adhesive film is peeled off, and polyethylene terephthalate (PET75) having a thickness of 75 μm is bonded to the surface of the adhesive layer to prepare an adhesive sheet, and the production is performed. The adhesive sheet is cut to a width of 25 mm. Then, it is pressed twice by a 2kg roller to make a test. Test piece. After the test piece was allowed to stand for 1 hour, the peel strength (T-type peeling force) was measured at a peeling speed of 300 mm/min in an environment of 23° C. and 50% RH, and this value was used as an adhesive force.

[Method for evaluating water resistance]

The pressure-sensitive adhesive sheet obtained by the above-mentioned [method for evaluating the adhesion of the substrate] was immersed in water at 25 ° C for 4 hours. After the immersion, the peel strength (T-type peeling force) was measured in the same manner as the above [Method for evaluating the adhesion to the substrate], and the adhesion was after immersion.

The water resistance is determined by comparing the adhesion measured in the above [Method for evaluating the adhesion of the substrate] with the adhesion after the immersion.

In other words, it is judged as follows: [adhesive strength after immersion] / [adhesive force measured in the above [method for evaluating adhesion to a substrate]] × 100 (%) 85% or more: "○", 70% or more and less than 85%: "△", less than 70%: "X".

In addition, the abbreviation in Table 1 will be described.

"BA": butyl acrylate

"ACMO'": acryloyl morpholine

"C-1": 2-hydroxy-2-methyl-1-phenylpropan-1-one

"C-2": 2,4,6-trimethoxybenzimidyldiphenylphosphine oxide

"Clearon K-100": a terpene-based saturated resin aromatic modified product (manufactured by Anhara Chemical Co., Ltd.)

"Clearon K-4100": a terpene-based saturated resin aromatic modified product (manufactured by Anhara Chemical Co., Ltd.)

"Haritack PCJ": Polymerized rosin ester (made by Harima Chemicals Co., Ltd.)

"Pinecrystal KE-395": hydrogenated rosin ester (manufactured by Arakawa Chemical Industries Co., Ltd.)

"FTR-0100": α-methylstyrene homopolymer (manufactured by Mitsui Chemicals Co., Ltd.)

Claims (3)

A resin composition for an ultraviolet curable adhesive, comprising: a (meth)acrylic acid amino group obtained by reacting a polyol (a), a polyisocyanate (b), and a (meth)acrylic compound (c) having a hydroxyl group; a tomate resin (A), a (meth)acrylic monomer (B), a photopolymerization initiator (C), and an adhesion-imparting agent (D); and the resin composition for an ultraviolet-curable adhesive is characterized by the above The adhesion-imparting agent (D) is one or more kinds of unsaturated aromatic compounds (d-1) selected from the group consisting of styrene, α-methylstyrene, vinyltoluene, hydrazine, and isopropenyltoluene. Obtained by reacting with one or more kinds of unsaturated aliphatic compounds (d-2) selected from the group consisting of isobutylene, butadiene, isoprene, pentadiene and dicyclopentadiene, wherein the above photopolymerization The initiator (C) contains 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2,4,6-trimethylbenzimidyldiphenylphosphine oxide. The resin composition for an ultraviolet curable adhesive according to the first aspect of the invention, wherein the photopolymerization initiator (C) contains 2-hydroxy-2-methyl in a mass ratio of 20/80 to 80/20. Base-1-phenylpropan-1-one and 2,4,6-trimethylbenzimidyldiphenylphosphine oxide. An adhesive obtained by using the resin composition for an ultraviolet curable adhesive according to the first or second aspect of the invention.