TWI544047B - Resin composition for ultraviolet cure adhesive, adhesive and laminate - Google Patents

Description

Resin composition, adhesive and laminate for ultraviolet curing adhesive

The present invention relates to a resin composition, an adhesive, and a laminate for an ultraviolet curing adhesive having excellent adhesion and retention.

In an optical related article in which a touch panel or a liquid crystal display is exemplified, an optical member having various materials or shapes is used in a large amount as it is highly functionalized.

In the bonding of the optical members as described above, adhesives have been conventionally used, but the industry requires an adhesive having excellent adhesion regardless of the material or shape of the parts.

Moreover, in the manufacture of this optical related product, in recent years, the productivity improvement of a final product has become a great problem. Since the adhesive used in the prior art 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 takes a long time. It becomes a cause of lowering the production efficiency of the final product.

As an adhesive which can improve the production efficiency of the above-mentioned products, an ultraviolet curing adhesive is known. Since the ultraviolet curable adhesive generally does not contain a solvent such as a solvent or water, it is not necessary to remove the solvent when forming the adhesive layer.

An adhesive having a level of adhesion which can be used for the manufacture of the aforementioned article or the like, and which can improve the production efficiency of the final product as compared with the prior art, for example, an adhesive composition is known which is characterized in that: 100 parts of a monomer having an unsaturated double bond, and containing 5 parts by mass or more and 200 parts by mass or less of a high molecular weight body having an urethane bond and having an unsaturated double bond at a polymer terminal and having a weight average molecular weight of 20,000 or more (For example, refer to Patent Document 1).

However, the adhesive composition may not exhibit sufficient adhesive force in practical use depending on the material of the substrate, etc., and depending on the material or shape of the substrate, peeling may occur over time, and the substrate may be opposed to the substrate. The offset of the lateral force parallel to the surface of the aforementioned substrate.

[Previous Technical Literature] [Patent Literature]

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

The problem to be solved by the present invention is to provide a resin composition for an ultraviolet curable adhesive, which has excellent adhesion and retention for a substrate which is formed of various materials and shapes without causing peeling with time.

The inventors of the present invention conducted intensive studies in order to solve the above problems, and have focused on a (meth)acrylic monomer used in combination with an urethane (meth) acrylate resin.

However, when a single (meth)acrylic component is used as the (meth)acrylic monomer, an adhesive having both adhesive strength and holding power cannot be obtained.

Therefore, the inventors of the present invention have conducted intensive studies focusing on the control of the cohesive force caused by the glass transition temperature of the (meth)acrylic monomer.

As a result, it has been found that a (meth)acrylic monomer having a specific glass transition temperature and a (meth)acrylic monomer having a specific glass transition temperature is used in combination with a (meth)acrylic monomer having a specific glass transition temperature. When used in combination with an urethane (meth) acrylate resin, an adhesive having excellent adhesion and retention can be obtained. The present invention has been completed.

In particular, the present invention provides a resin composition for an ultraviolet curable adhesive, which comprises reacting a polyol (a), a polyisocyanate (b), and a hydroxyl group-containing (meth)acrylic compound (c). a resin composition for an ultraviolet curable adhesive of a urethane (meth) acrylate resin (A), a (meth) acryl monomer (B), and a photopolymerization initiator (C), Its characteristics are:

The (meth)acrylic monomer (B) contains a nitrogen-containing (meth)acrylic monomer (b-1) which forms a homopolymer at a glass transition temperature of 50 ° C or higher, and has a glass transition temperature of -20 ° C or lower. The (meth)acrylic monomer (b-2) which forms a homopolymer, and the mass ratio of the (b-1) to the (b-2) is (b-1)/(b- 2) = 20/80~60/40.

The resin composition for an ultraviolet curable adhesive of the present invention contains a glycolic acid B obtained by reacting a polyol (a), a polyisocyanate (b), and a hydroxyl group-containing (meth)acrylic compound (c). A resin composition for an ultraviolet curable adhesive of an ester (meth) acrylate resin (A), a (meth)acrylic monomer (B), and a photopolymerization initiator (C), the (meth) The acrylic monomer (B) contains a nitrogen-containing (meth)acrylic monomer (b-1) which can form a homopolymer having a glass transition temperature of 50 ° C or higher, and a glass transition temperature of -20 ° C or lower can form homopolymerization. The (meth)acrylic monomer (b-2) is formed, and the mass ratio of (b-1) to (b-2) is (b-1)/(b-2)=20. /80~60/40, it provides adhesives with excellent adhesion and retention. The adhesive composed of the resin composition for an ultraviolet curable adhesive of the present invention can be suitably used as an adhesive used in an optical member. In particular, it can be suitably used for manufacturing a liquid crystal touch panel, a liquid crystal display, a plasma display, an organic EL, or the like.

The resin composition for an ultraviolet curable adhesive of the present invention contains the urethane (meth) acrylate resin (A), the (meth) acryl monomer (B), and the photopolymerization initiator ( C), and other additives as needed.

The resin composition for an ultraviolet curing adhesive may be the urethane (meth) acrylate resin (A), the (meth) acryl monomer (B), and the photopolymerization initiator. (C) and an additive or the like are dissolved or dispersed in a solvent such as an organic solvent or an aqueous medium, but the urethane (meth)acrylic acid is dissolved or dispersed in the (meth)acrylic monomer (B). When the composition of the ester resin (A), the photopolymerization initiator (C), or the like is bonded to the substrate to form a laminate, the step of removing the solvent contained in the binder is not required, and further It is preferable to increase the production efficiency of the above laminate.

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

The urethane (meth) acrylate resin (A) is obtained by reacting a polyol (a), a polyisocyanate (b), and a hydroxyl group-containing (meth)acrylic compound (c).

The urethane (meth) acrylate resin (A) has a (meth) acrylonitrile group which is subjected to radical polymerization by light irradiation, heating, or the like. The equivalent weight of the (meth)acryl fluorenyl group is preferably in the range of 4,000 to 9000, particularly preferably from the viewpoint of having excellent adhesion and retention and forming an adhesive layer having good transparency. It is 5000~8000. In addition, the equivalent weight of the (meth) acrylonitrile group means that the total mass of the polyol (a), the polyisocyanate (b), and the hydroxyl group-containing (meth)acrylic compound (c) is divided by the aforementioned A value obtained by the equivalent of the (meth)acryl fluorenyl group present in the urethane (meth) acrylate resin (A).

The urethane (meth) acrylate resin (A) has a weight average molecular weight of 1,000 to 50,000, from the viewpoint of having excellent adhesion and retention and imparting good coating workability. The resin is preferable, and a resin having a weight average molecular weight of 10,000 to 25,000 is more preferable, and a range of 12,000 to 25,000 is particularly preferable. Furthermore, the aforementioned urethane (meth) acrylate resin (A) The weight average molecular weight is a value obtained by gel permeation chromatography (GPC) by styrene conversion.

The polyol (a) is not particularly limited, and a polyester polyol, a polyether polyol, a polycarbonate polyol, a polyacryl polyol, or the like can be used, and these polyols can be used singly or in combination of two or more. . Among them, a polyether polyol is particularly preferable because it can have excellent adhesion and retention, and can improve durability of the adhesive film, particularly hydrolysis resistance.

Examples of the polyether polyol which can be used in the above-mentioned polyol (a) include one or two or more kinds of alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide, and compounds having two or more active hydrogens. a product obtained by addition polymerization, polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran, denatured polytetramethylene glycol obtained by copolymerizing tetrahydrofuran and alkyl-substituted tetrahydrofuran, and copolymerization of neopentyl glycol and tetrahydrofuran Denatured polybutanediol.

As the compound having two or more active hydrogens, for example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, or the like can be used. Propylene 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, glycerin, diglycerin, trimethylolpropane, Ditrimethylolpropane, trishydroxymethylpropane, 1,2,6-hexanetriol, triethanolamine, triisopropanolamine, pentaerythritol, dipentaerythritol, sorbitol, sucrose, ethylenediamine, N- Ethyl diethylamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,2-diaminobutane, 1,3-diaminobutane, 1,4 - Diaminobutane, di-ethyltriamine, phosphoric acid, acid phosphate, and the like.

Further, in addition to the compounds, polyethers having an alicyclic structure may also be used. Alcohol.

Among these, it is more preferable to use an aliphatic polyether polyol from the viewpoint of imparting good adhesive properties, and it is particularly preferable to use polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran.

The polyol (a) may be used in combination with other polyester polyols, polyether polyols, polycarbonate polyols, polyacrylic polyols, and the like as described above, in combination with other active hydrogen-containing chain extenders.

The other active chain-containing extender containing active hydrogen may be used singly or in combination of two or more kinds thereof, for example, ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 2 , 3-butanediol, 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 dihydroxyethyl ether, etc., B Diamine, propylenediamine, hexamethylenediamine, trimethylhexamethylenediamine, isophoronediamine, 4,4'-dicyclohexylmethanediamine, diaminocyclohexane, A polyamine such as methyldiamine cyclohexane or norbornene diamine.

As the polyol (a), a polyol having a weight average molecular weight in the range of 500 to 2,000 is preferably used from the viewpoint of imparting good cohesive force and flexibility to the adhesive layer, and particularly preferably used. A polyol having a weight average molecular weight in the range of 500 to 1,500. Further, the weight average molecular weight of the polyol (a) is a value obtained by gel permeation chromatography (GPC) in terms of styrene.

The polyisocyanate (b) may be used singly or in combination of two or more kinds thereof, for example, an aromatic such as xylylene diisocyanate, phenyl diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate or naphthalene diisocyanate. Diisocyanate, hexamethylene diisocyanate, diazonic acid diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, diiso A diisocyanate or the like containing an aliphatic or aliphatic cyclic structure such as cyanate group methylcyclohexane or tetramethylxylylene diisocyanate. Among these, it is preferable to use a diisocyanate containing an aliphatic cyclic structure, and it is preferable to use a 4,4'-bicyclic ring, from the viewpoint of having excellent adhesion and retention, and improving heat-resistant yellowing. Hexyl methane diisocyanate, isophorone diisocyanate, cyclohexane diisocyanate, diisocyanate methylcyclohexane.

When the (meth)acrylic compound (c) containing a hydroxyl group is a (meth)acryloyl group introduced into the urethane (meth)acrylate resin (A), it is used by a user. A compound capable of reacting a hydroxyl group with an isocyanate group.

As the hydroxyl group-containing (meth)acrylic compound, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl acrylate, or (methyl) can be used. a hydroxyl group-containing (meth)acrylic acid alkyl ester or trimethylolpropane di(meth)acrylate such as 3-hydroxybutyl acrylate, 4-hydroxybutyl (meth)acrylate or 6-hydroxyhexyl acrylate. A hydroxyl group-containing polyfunctional (meth) acrylate such as pentaerythritol tri(meth) acrylate or dipentaerythritol penta (meth) acrylate, polyethylene glycol monoacrylate, or polypropylene glycol monoacrylate. Among these, it is more preferable to use 2-hydroxyethyl acrylate or 4-hydroxybutyl acrylate from the viewpoints of easiness of obtaining raw materials, curability, and impartability of good adhesion properties.

As a method for producing the urethane (meth) acrylate resin (A), for example, a method in which the polyol (a) and the hydroxy group are contained in the reaction system are added in the absence of a solvent After the (meth)acrylic compound (c), the polyisocyanate (b) is supplied, mixed and reacted to produce a urethane (meth)acrylate resin (A); in the absence of a solvent By reacting the polyol (a) with the polyisocyanate (b) to obtain an urethane prepolymer having an isocyanate group at a molecular terminal, and then supplying the hydroxyl group-containing (meth)acrylic compound (c) A method of producing a urethane (meth) acrylate resin (A) by mixing and reacting it. Any of the foregoing reactions should be carried out at a temperature of 20 to 120 ° C for about 30 Minutes ~ 24 hours or so.

The production of the urethane (meth) acrylate resin (A) may be carried out in the presence of an organic solvent or an aqueous medium. Further, it may be produced in the presence of a (meth)acrylic monomer (B) to be described later instead of an organic solvent or an aqueous medium. In the case of producing a laminate, since it is not necessary to remove an organic solvent or an aqueous medium, the production step can be simplified, and therefore it is preferable to carry out the solvent-free or (meth)acrylic acid from the viewpoint of suppressing the viscosity in the reaction system. It is carried out in the presence of a monomer (B).

The reaction between the polyol (a) and the polyisocyanate (b) and the hydroxyl group-containing (meth)acrylic compound (c), the hydroxyl group of the polyol (a) and the hydroxyl group-containing (methyl group) The total amount of the hydroxyl groups of the acrylic compound (c) is within the range of the equivalent ratio of the isocyanate groups of the polyisocyanate (b) [the total amount of isocyanate groups/hydroxy groups] = 0.75 to 1.00, provided that The molecular weight of the obtained urethane (meth) acrylate resin (A) is preferably controlled, and it is particularly preferably in the range of 0.79 to 0.95. Further, in the case where the equivalent ratio exceeds 1, the reaction may be carried out. However, in this case, in order to inactivate the terminal isocyanate group of the urethane (meth) acrylate resin (A), an alcohol such as methanol is preferably used. In this case, the hydroxyl group of the polyol (a) and the hydroxyl group of the hydroxyl group-containing (meth)acrylic compound (c) and the total amount of the hydroxyl groups of the alcohol are preferably the polyisocyanate group. The equivalent ratio [the total amount of isocyanate groups/hydroxy groups] is adjusted to the above range.

In addition, as the alcohol to be used for inactivating the terminal isocyanate group of the urethane (meth) acrylate resin (A), for example, a monofunctional alcohol such as methanol, ethanol, propanol or butanol may be used. A bifunctional alcohol composed of a hydroxyl group of a first order and a second order, such as 1,2-propanediol or 1,3-butanediol.

Further, in the production of the urethane (meth) acrylate resin (A), a polymerization inhibitor, an urethane catalyst or the like may be used as needed.

As the polymerization inhibitor, for example, 3,5-bis-tert-butyl-4-hydroxytoluene, hydroquinone, methylhydroquinone, hydroquinone monomethyl ether (p-methoxyphenol), p-tert-butyl can be used. Camelliol, methoxyphenol, 2,6-di-t-butyl cresol, phenothiazine, tetramethylthiuram disulfide, diphenylamine, dinitrobenzene, and the like.

As the urethane catalyst, for example, a nitrogen-containing compound such as triethylamine, triethylenediamine or N-methylmorpholine, a metal salt such as potassium acetate, zinc stearate or tin octylate, or lauric acid can be used. An organometallic compound such as butyltin.

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

The (meth)acrylic monomer (B) contains a nitrogen-containing (meth)acrylic monomer (b-1) which can form a homopolymer having a glass transition temperature of 50 ° C or higher, and a glass transition temperature of -20 ° C. The (meth)acrylic monomer (b-2) which can form a homopolymer is as follows.

The nitrogen-containing (meth)acrylic monomer (b-1) which forms a homopolymer at a glass transition temperature of 50 ° C or higher can be preferably improved from the viewpoint of further improving the excellent adhesion and retention. It is a nitrogen-containing (meth)acrylic monomer which can form a homopolymer at a glass transition temperature of 55 to 160 ° C, and more preferably, a glass transition temperature of 140 to 160 ° C can form a homopolymer containing nitrogen. (Meth)acrylic monomer (b-1).

Examples of the nitrogen-containing (meth)acrylic monomer which can be used in the above (b-1) include (meth) acrylamide, dimethyl (meth) acrylamide, and diethyl. (Meth) acrylamide, N,N-dimethylaminopropyl (meth) acrylamide, N,N-dimethylaminopropyl (meth) acrylamide, N, N- Dimethylpropyl (meth) acrylamide chlorinated methane 4-grade salt, (meth) propylene decylmorpholine, isopropyl (meth) acrylamide, N-(methyl) propylene decyloxy Ethyl hexahydrophthalic acid imine, hydroxyethyl (meth) acrylamide, etc. may be used alone or in combination of two or more.

Among these, acrylic acid containing nitrogen is preferably used from the viewpoint of improving hardenability. The monomer is more preferably acryloylmorpholine, dimethyl acrylamide, dimethylaminopropyl acrylamide, or N, from the viewpoint of further improving the adhesion and retention. - propylene methoxyethyl hexahydrophthalimide, and particularly preferably acryloyl morpholine.

The (meth)acrylic monomer (b-2) which can form a homopolymer having a glass transition temperature of -20 ° C or less can be further improved from the viewpoint of further improving the adhesion and holding power. A (meth)acrylic monomer which can form a homopolymer at a conversion temperature of from -25 to -80 °C.

Examples of the (meth)acrylic monomer which can be used in the above (b-2) include ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, and acrylic acid. N-amyl ester, isoamyl acrylate, n-hexyl acrylate, n-heptyl acrylate, isoheptyl acrylate, n-octyl acrylate, isooctyl acrylate, decyl acrylate, n-lauryl methacrylate, tridecane methacrylate Base ester, isomyristyl acrylate, 2-ethylhexyl acrylate, 2-methylbutyl acrylate, 3-methylbutyl acrylate, 2-methylpentyl acrylate, 2-methoxyethyl acrylate, 3-methoxypropyl acrylate, 3-methoxybutyl acrylate, 2-ethoxyethyl acrylate, 2-ethoxypropyl acrylate, 2-ethoxybutyl acrylate, etc., such monomers They may be used alone or in combination of two or more.

Among these, an acrylic monomer is preferably used from the viewpoint of improving the curability, and it is more preferable to use n-butyl acrylate or 2-ethyl acrylate from the viewpoint of further improving the adhesion and retention. Hexyl ester.

Since the mass ratio of the above (b-1) to the above (b-2) in the (meth)acrylic monomer is (b-1)/(b-2)=20/80 to 60/40, An adhesive that has excellent adhesion and retention can be obtained. Among them, the mass ratio of the above (b-1) to the above (b-2) is preferably (b-1)/(b-2)=30/ according to the viewpoint of further improving the excellent adhesion and retention. 70~50/50. When the mass ratio of the above (b-1) to the above (b-2) is the aforementioned (b-1) When the mass ratio is less than 20, the adhesive strength is deteriorated, and when it is more than 60, the hardness is high due to high cohesive force, and the problem of the adhesive is not obtained.

Further, the (meth)acrylic monomer used in the present invention may be used in combination with other ethylene in addition to the above (b-1) and (b-2) within the range not impairing the effects of the present invention. Base monomer.

Examples of the other vinyl monomer include (meth)acrylic acid, dimethylaminoethyl (meth)acrylate, N-methylol acrylamide, N-vinylpyrrolidone, acrylonitrile, and N- Vinyl methamine, itaconic acid (anhydride), maleic acid (anhydride), fumaric acid, crotonic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, (methyl ) methyl acrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl (meth)acrylate, A N-amyl acrylate, isoamyl methacrylate, neopentyl methacrylate, n-hexyl methacrylate, n-heptyl methacrylate, isoheptyl methacrylate, n-octyl methacrylate, methacrylic acid Isooctyl ester, decyl methacrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl methacrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, A Phenyl acrylate, glycidyl methacrylate, benzyl (meth) acrylate, trifluoromethyl methyl (meth) acrylate, (methyl) Ethyl 2-trifluoromethylethyl ester, 2-perfluoroethyl ethyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutyl ethyl (meth)acrylate, (methyl) 2-Perfluoroethyl acrylate, perfluoromethyl (meth) acrylate, diperfluoromethyl methyl (meth) acrylate, 2-perfluoromethyl-2-perfluoroethyl (meth) acrylate Ester, 2-perfluorohexylethyl (meth)acrylate, 2-perfluorodecylethyl (meth)acrylate, 2-perfluorohexadecyl (meth)acrylate, etc. (meth)acrylic acid Monomer, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, pentaerythritol a (meth)acrylic monomer containing a hydroxyl group such as (meth) acrylate, styrene, p-methylstyrene, ethylstyrene, propylstyrene, isopropylstyrene, p-tert-butylbenzene A vinyl monomer such as a styrene monomer such as ethylene, vinyl acetate, vinyl propionate or vinyl pivalate.

The amount of the (meth)acrylic monomer (B) used is 100 parts by mass based on the urethane (meth)acrylate resin (A), from the viewpoint of having excellent adhesion and holding power. It should be used in the range of 30 to 200 parts by mass, more preferably in the range of 40 to 150 parts by mass, and particularly preferably in the range of 50 to 100 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, heating, or the like to form the urethane (meth) acrylate resin (A) and the (meth) acrylic monomer (B). The radical polymerization begins.

As the photopolymerization initiator, for example, 4-phenoxydichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1 can be used. -(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 4-(2-hydroxyethoxy)-phenyl (2- Hydroxy-2-propyl)one, 2-methyl-[4-(methylthio)phenyl]-2-morpholinyl-1-propanone, 2,2-dimethoxy-2-phenylbenzene Acetophenones such as ketone; benzoin, benzoin methyl ether, benzoin isoethyl ether, benzoin isopropyl ether, benzoin isobutyl ether and other benzoin; benzophenone, benzamidine benzoic acid, benzamidine Methyl formate, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzylidene-4'-methyldiphenyl sulfide, 3,3'-dimethyl-4-methoxy Benzophenones such as benzophenone; thioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, Thiophenones such as 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone; 4,4'-dimethylaminothioxanthone (alias Miranesone), 4,4'-diethylaminobenzophenone, α-mercaptodecyl ester Anthraquinone, methylbenzate ("Vicure 55"), 2-ethyl hydrazine and the like; 2,4,6-trimethylbenzimidyldiphenylphosphine oxide (" Lucirin TPO"), bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide ("IRGACURE 819") and other fluorenylphosphine oxides; 3,3',4,4'-tetra Third butyl peroxycarbonyl) benzophenone ["BTTB" manufactured by Nippon Oil & Fat Co., Ltd.], benzoated benzophenone, and the like.

The photopolymerization initiator can have excellent adhesion and retention, and can prevent discoloration of the adhesive layer with time, and can improve the phase of the specific (meth)acrylic monomer used in the present invention. From the viewpoint of capacitance and hardenability, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, and 2,4,6-trimethylbenzimidazole are preferably used. Diphenylphosphine oxide, bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide. Among them, it is preferred to use one of the above 2-hydroxy-2-methyl-1-phenylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone or a combination of two, and 2, 4, 6-three. One type or a combination of two kinds of methyl benzepidine diphenylphosphine oxide and bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide may be used in combination.

Further, one or a combination of the above 2-hydroxy-2-methyl-1-phenylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone is used, and 2, 4, 6-three are used in combination. When one type or a combination of two kinds of methyl benzepidine diphenylphosphine oxide and bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide is used, it is possible to further From the viewpoint of improving the compatibility and curability of the specific (meth)acrylic monomer used in the present invention, it is more preferred to use 2-hydroxy-2-methyl at a mass ratio of 20/80 to 80/20. One of -1-phenylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone or a combination of two, 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, bis ( One type or a combination of 2,4,6-trimethylbenzylidene)-phenylphosphine oxide is used in combination, and it is particularly preferably used in a ratio of 45/55 to 65/35.

The amount of use of the photopolymerization initiator (C) is preferably from 0.1 to 20 parts by mass, more preferably from 100 parts by mass of the urethane (meth)acrylate resin (A). It is used in the range of 0.5 to 15 parts by mass.

Further, in the case where the binder composed of the resin composition for an ultraviolet curable adhesive of the present invention is used for an optical member, it is preferably an ultraviolet curing type of the present invention from the viewpoint of improving light resistance stability. The light stabilizer composition further contains a light stabilizer (D).

The light stabilizer (D) is a substance that traps radicals generated by photodegradation. For example, a radical scavenger such as a thiol system, a thioether system or a hindered amine compound, or a benzophenone system can be used. For the ultraviolet absorber such as a benzoate compound, these light stabilizers may be used singly or in combination of two or more kinds. Among them, it is preferable to use a hindered amine 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. a compound.

The hindered amine-based compound may, for example, be cyclohexane and N-butyl 2,2,6,6-tetramethyl-4-piperidinamine-2,4,6-trichloro 1,3. , a reaction product of a reaction product of 5-triazine and 2-aminoethanol (trade name: Tinuvin (registered trademark) 152 (manufactured by BASF Japan Co., Ltd.), and azelaic acid bis (2, 2, 6, 6-Tetramethyl-1-(octyloxy)-4-piperidyl)ester (trade name: Tinuvin (registered trademark) 123 (manufactured by BASF), 1,1-dimethylethyl hydrogen A hindered amine compound having an aminoether group such as a reaction product of a peroxide and octane, N-acetyl-3-dodecyl-1-(2,2,6,6-tetramethyl-4- N-ethinyl hindered amine compound such as piperidinyl)pyrrolidine-2,5-dione (trade name: Hostavin (registered trademark) 3058 (manufactured by Clariant Japan Co., Ltd.), double (1, 2, 2,6,6-pentamethyl-4-piperidinyl) sebacate (trade name: Sanol LS765 (BASF Japan)), double (1,2,2,6,6-five 4-[piperidinyl){[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl}butylmalonate Trade name: Tinuvin (registered trademark) 144 (BASF Japan Co., Ltd.), a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (trade name: Tinu Vin (registered trademark) 622LD (BASF Japan Co., Ltd.), malonic acid [{4-methoxyphenyl}methylene]-bis(1,2,2,6,6-pentamethyl- An N-alkyl hindered amine compound such as 4-piperidinyl)ester (trade name: Hostavin (registered trademark) PR-31 (manufactured by Clariant Japan Co., Ltd.)). Among them, it is particularly preferable to maintain the compatibility and the holding power with excellent adhesion and further improve the compatibility with the specific (meth)acrylic monomer used in the present invention and light stability. A hindered amine compound having an aminoether group.

The light stabilizer (D) is used in an amount relative to the aforementioned urethane (meth) acrylate resin (A) 100 from the viewpoint of imparting heat yellowing resistance to the adhesive film. The mass part is preferably used in the range of 0.01 to 10 parts by mass, more preferably in the range of 0.1 to 5 parts by mass.

Further, in the case where the adhesive composed of the resin composition for an ultraviolet curable adhesive of the present invention is used for an optical member, it is preferable that the ultraviolet curable type of the present invention is the viewpoint of improving heat-resistant yellowing. The adhesive composition further contains an antioxidant (E).

The antioxidant (E) includes a hindered phenol-based compound (primary antioxidant) that captures a radical generated by thermal deterioration, and a phosphorus-based or sulfur-based compound that decomposes a peroxide generated by thermal deterioration. Secondary antioxidants, etc., these antioxidants may be used singly or in combination.

The hindered phenol-based compound may, for example, be triethylene glycol-bis-[3-(3-tert-butyl-5-methyl-4hydroxyphenyl)propionate] (trade name: IRGANOX (registered) Trademark) 245 (BASF Japan Co., Ltd.), pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate (trade name: IRGANOX (registered trademark) 1010 (BASF) Japan (stock))), octadecyl [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate (trade name: IRGANOX (registered trademark) 1076 (BASF Japan) ))), thiodiethyl bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (trade name: IRGANOX (registered trademark) 1035 (BASF Japan ( (Production)), 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 Co., Ltd.), 4,6-bis(dodecylthiomethyl) o-cresol (trade name: IRGANOX (registered trademark) 1726 (manufactured by BASF Japan Co., Ltd.), N-phenyl Reaction product of aniline with 2,4,4-trimethylpentene (trade name: IRGANOX (registered trademark) 5057 (manufactured by BASF Japan Co., Ltd.), 2-t-butyl-6-(3 third Butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate (commodity Name: Sumilizer (registered trademark) GM (manufactured by Sumitomo Chemical Co., Ltd.), 3,9-bis[2-[3-(t-butyl-4-hydroxy-5-methylphenyl)propoxyloxy ]-1,1-Dimethylethyl]2,4,8,10-tetraoxaspiro[5.5]undecane (trade name: Sumilizer (registered trademark) GA-80 (Sumitomo Chemical Co., Ltd.) )), 2,6-di-t-butyl-4-methylphenol (trade name: Nocrac 200 (made by Ouchi Emerging Chemical Industry Co., Ltd.)), 2,2'-methylene double (4-A) -6-tert-butylphenol) (trade name: NocracNS-6 (made by Ouchi Emerging Chemical Industry Co., Ltd.)), 2,5-di-t-amylhydroquinone (trade name: NocracDAH) Industrial (share) system, etc.

Examples of the phosphorus-based compound include triphenylphosphine, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethylphosphite, and phosphorous acid triphosphate. Phenyl ester, tridecyl phenyl phosphite, tris(2,4-dibutylphenyl) phosphite, tris(2,4-dibutyl-5-methylphenyl) phosphite, three [2-Terbutyl-4-(3-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl]phosphite, tridecyl phosphite, octyl Diphenyl phosphite, bis(indenyl)monophenylphosphite, ditridecylpentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, bis (2,4 -dibutylphenyl)pentaerythritol diphosphite, bis(2,6-dibutyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tributylphenyl) Pentaerythritol diphosphite, bis(2,4-diisopropylphenylphenyl)pentaerythritol diphosphite, tetrakis(tridecyl)isopropylidenediphenol 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 triphosphite, tetra (2,4 -dibutylphenyl)biphenylene diphosphinate, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 2,2'-methylene double ( 4,6-butylphenyl)-2-ethylhexyl phosphite, 2,2'-methylenebis(4,6-butylphenyl)-octadecylphosphite, 2,2 '-Extended ethyl bis(4,6-dibutylphenyl)fluorophosphite, tris(2-[(2,4,8,10-tetrabutyldibenzo[d,f][1, 3,2]dioxaphosphon-6-yl)oxy]ethyl)amine, 2-ethyl-2-butylpropanediol, and a phosphite of 2,4,6-tributylphenol.

Examples of the sulfur-based compound include bis(dodecyl)-3,3'-thiopropionate, dilauryl-3,3'-thiodipropionate, and dilaurylthio. Disulfate, ditridecyl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3' - thiodipropionate, tetra-methylene-3-laurylthiopropionate methane, distearyl-3,3'-methyl-3,3'-thiodipropionate, Lauryl stearyl-3,3'-thiodipropionate, bis[2-methyl-4-(3-n-alkylthiopropoxy)-5-tert-butylphenyl] sulfide , β-lauryl thiopropionate, 2-mercaptobenzimidazole, 2-mercapto-5-methylbenzimidazole, dioctadecyl-3,3'-thiodipropionate Wait.

Among these, it is preferable to maintain the compatibility with the specific (meth)acrylic monomer used in the present invention and the heat-resistant yellowing resistance while maintaining excellent adhesion and retention, and further improving the compatibility with the specific (meth)acrylic monomer used in the present invention. Phosphorus-based compounds, particularly preferably using triphenylphosphine, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite, pentaerythritol tetra [3-( 3,5-Di-t-butyl-4-hydroxyphenyl)propionate.

The antioxidant (E) is used in an amount of 0.01 to 100 parts by mass based on 100 parts by mass of the urethane (meth) acrylate 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 to 5 parts by mass.

Further, the adhesive comprising the resin composition for an ultraviolet curable adhesive of the present invention is used for an optical member, and particularly for use in the manufacture of a liquid crystal touch panel, according to the prevention of indium tin oxide as a transparent conductive material. From the viewpoint of metal corrosion (rust resistance) of (hereinafter referred to as ITO), it is preferable that the ultraviolet curable adhesive composition of the present invention further contains a rust inhibitor (F).

As the rust inhibitor (F), for example, a triazole compound, an organic carboxylic acid amine salt, an nitrite amine salt, an ammonium phosphate salt, an amine carbonate, a heterocyclic amine or the like can be used, and these may be used singly or in combination. The specific (meth)acrylic monomer used in the present invention can be further improved according to the maintenance of excellent adhesion and retention, and without impairing light stability and heat yellowing resistance. From the viewpoint of compatibility and rust resistance, a triazole compound is preferably used.

As the aforementioned triazole-based compound, for example, 1-[bis(2-ethylhexyl)aminomethyl]benzotriazole, methylbenzotriazole, dimethylbenzotriazole, ethylbenzene can be used. Triazole, ethylmethylbenzotriazole, diethylbenzotriazole, unsubstituted benzotriazole, 5-methyl-1H- Benzotriazole, N,N-bis(2-ethylhexyl)-(4 or 5)-methyl-1H-benzotriazol-1-methylamine, three represented by the following general formula (1) An azole compound or the like.

(wherein R1 and R2 are each independently, and 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 7 carbon atoms; 13 aralkyl groups, 6 to 10 carbon atoms, hydroxy groups.)

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 can be suitably used.

As the triazole-based compound, commercially available products such as "IRGAMET (trademark registration) 30" and "IRGAMET (trademark registration) 38S" (above, BASF Japan Co., Ltd.) can be used.

The amount of the rust inhibitor (F) used is 100 parts by mass based on the urethane (meth) acrylate resin (A), from the viewpoint of imparting good rust resistance without lowering the adhesive properties. It is preferably used in the range of 0.001 to 5 parts by mass, more preferably in the range of 0.01 to 2 parts by mass.

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 by the following method, for example, after separately preparing an urethane (meth) acrylate resin (A), a method of mixing a (meth)acrylic monomer (B), a photopolymerization initiator (C), and, if necessary, a light stabilizer (D), an antioxidant (E), and a rust inhibitor (F); Alternatively, the ethyl urethane (meth) acrylate resin (A) is produced in the presence of a part or all of the (meth)acrylic monomer (B), and the polymerization initiator (C) and light resistance as needed are provided. A method of mixing a stabilizer (D), an antioxidant (E), and a rust preventive (F).

The resin composition for the ultraviolet curable adhesive obtained by the above method is not particularly limited, but the viscosity is preferably from 500 to 20,000 mPa from the viewpoint of good coatability and rationality of the adhesive solution at the time of application. s, more preferably 1000~10000mPa. s. Further, the viscosity is 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 components.

As the other additives, for example, a thixotropic imparting agent, a sensitizer, a polymerization inhibitor, a hardener, a hardening accelerator, a leveling agent, a tackifier, a wax, a heat stabilizer, and a fluorescent whitening can be used. Agent, foaming agent, thermoplastic resin, thermosetting resin, organic solvent, conductivity imparting agent, antistatic agent, moisture permeability improving agent, water repellent, hollow foam, compound containing crystal water, flame retardant, water absorption Agent, moisture absorbent, deodorant, foam stabilizer, antifoaming agent, antifungal agent, preservative, algicide, anti-caking agent, hydrolysis inhibitor, organic and inorganic water-soluble compound, and the like.

As the aforementioned sensitizer, for example, biphenyl, 1,4-dimethylnaphthalene, 9-fluorenone, anthracene, phenanthrene, triphenylene, anthracene, 9,10-diphenylanthracene, 9,10- can be used. Dimethoxy oxime, 9,10-diethoxy fluorene, 9,10-dipropoxy fluorene, 9,10-dibutoxy fluorene, benzophenone, 4,4'-dimethoxy Benzophenone, acetophenone, 4-methoxyacetophenone, benzaldehyde, and the like.

As the hardener, an adduct derived from toluene diisocyanate, hexamethylene diisocyanate or the like, a polyisocyanate compound typified by an isocyanurate or the like, a polyfunctional epoxy compound, a melamine compound, or a metal can be used. Chelate and the like.

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

The method of curing the resin composition for an ultraviolet curable adhesive of the present invention can be carried out, for example, 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. It is hardened by ultraviolet rays.

The irradiation of the ultraviolet rays is preferably in the range of 50 to 5,000 mJ/cm ² , more preferably in the range of 100 to 3,000 mJ/cm ² , and still more preferably in the range of 300 to 1,500 mJ/cm ² . Further, the amount of ultraviolet irradiation was measured using a value measured by a UV detector UVR-N1 (manufactured by GS Yuasa Co., Ltd.) in a wavelength region of 300 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 is possible to further promote hardening by heating at about 40 to 80 ° C after the irradiation of the ultraviolet rays as needed. .

The adhesive comprising the resin composition for an ultraviolet curable adhesive of the present invention has excellent adhesion and retention, and can be suitably used as an adhesive used in an optical member. In particular, it can be suitably used for manufacturing a liquid crystal touch panel, a liquid crystal display, a plasma display, an organic EL display, or the like.

Suitable examples of the adhesive composition comprising the resin composition for an ultraviolet curable adhesive of the present invention include, for example, a plastic substrate, a flexible printed substrate, and a glass in a liquid crystal touch panel. a substrate or a bonding agent for depositing a substrate such as graphene or ITO as a transparent conductive material on the substrate; and a transparent substrate made of glass, plastic or the like in the liquid crystal display An adhesive that adheres to the outermost polarizing plate constituting the liquid crystal panel; In a liquid crystal display, an adhesive or the like used in a space called an air gap provided between a transparent protective substrate made of glass, plastic, or the like and a liquid crystal panel.

The resin composition for an ultraviolet curable adhesive of the present invention comprises a binder, and the liquid crystal touch panel is used as a plastic substrate, a flexible printed substrate, a glass substrate, or steamed on the substrates. When a bonding agent such as a substrate made of graphene or ITO which is a transparent conductive material is used, the following method is employed: at least the viscosity of the resin composition for the ultraviolet curing adhesive of the present invention is used. On both sides of the layer (i) formed by the bonding agent, the lamination is composed of a substrate selected from the group consisting of a plastic substrate, a flexible printing substrate, a glass substrate, and an ITO (indium tin oxide) deposited on the substrates. Layer (ii) of one of the substrates in the group.

In the above-mentioned layer (i), an adhesive composed of a resin composition for an ultraviolet curable adhesive of the present invention can be used, and the thickness thereof varies depending on the field used for the liquid crystal touch panel, etc., but The thickness of the liquid crystal display is reduced, so it is preferably about 10 to 500 μm, more preferably 50 to 500 μm.

The layer (ii) is composed of one substrate selected from the group consisting of a plastic substrate, a flexible printed substrate, a glass substrate, and a substrate obtained by vapor-depositing ITO on the substrates. The same or different substrates can be used on both sides of the aforementioned layer (i).

As the plastic substrate, a base material composed of an acrylic resin or the like which is generally used, PC (polycarbonate), PBT (polybutylene terephthalate), PPS (polyphenylene sulfide), and denatured PPE can be used. Polyphenylene ether), PET (polyethylene terephthalate), COP (cycloolefin polymer), TAC (cellulose triacetate), anti-reflective film or sheet, antifouling film or sheet, forming a touch panel A film or sheet of a transparent conductive film.

A method of producing the above laminate, for example, a substrate selected from the group consisting of a plastic substrate, a flexible printed substrate, a glass substrate, or an ITO deposited thereon on the substrate (ii) Coating the ultraviolet of the present invention on the surface of one of the constituent groups After the resin composition for a wire-curable adhesive is irradiated with the ultraviolet rays, the other substrate is placed on the coated surface immediately, and the laminate of the present invention is obtained. Further, when the substrate is translucent, the resin composition for an ultraviolet curable adhesive of the present invention is applied onto the surface of the substrate, and the other substrate is placed on the coated surface, The laminate of the present invention can be obtained by irradiating the above-mentioned ultraviolet rays on a substrate.

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

[Examples]

Hereinafter, the present invention will be specifically described based on examples, but the scope of the present invention is not limited to the examples.

In the present invention, "parts" are "parts by mass" and "%" is "mass%" unless otherwise specified.

[Synthesis Example 1] <Synthesis of ethyl urethane (meth) acrylate resin (A-1)>

In a reaction vessel equipped with a stirrer, a reflux cooling tube, a nitrogen gas introduction tube, and a thermometer, 465.9 parts by mass of polytetramethylene glycol (weight average molecular weight: 1000), 9.6 parts by mass of 2-hydroxyethyl acrylate, and 2,6-two are added. 1.7 parts by mass of butyl cresol and 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. Then, 0.06 parts by mass of dioctyldi neodecanoate 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 of the isocyanate groups disappeared, and then cooled to obtain an urethane acrylate resin as (A-1). The obtained urethane acrylate 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] <Preparation of Resin Composition for UV Curing Adhesive>

In a container equipped with a stirrer, a reflux cooling tube, and a thermometer, 100 parts by mass of the urethane (meth) acrylate resin (A-1) obtained in Synthesis Example 1 and n-butyl acrylate were added at a temperature of 80 ° C in the container. 30 parts by mass, 30 parts by mass of acryloylmorpholine, and stirred until homogeneous. Thereafter, it was cooled to room temperature, and 4 parts by mass of 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2,4,6-trimethoxybenzimidylbenzene were sequentially added under stirring. 3 parts by mass of phosphine oxide, and stirred until homogeneous. Subsequently, it was filtered through a 200 mesh metal mesh to obtain a resin composition for an ultraviolet curing adhesive.

[Examples 2 to 7, Comparative Examples 1 to 4]

The type and amount of the component (b-1), the amount of the component (b-2), and the amount of the photopolymerization initiator (C) are changed as shown in Tables 1 to 3, and In the same manner as in Example 1, a resin composition for an ultraviolet curable adhesive was obtained.

[How to make adhesive film]

The resin composition for ultraviolet curable adhesives obtained in the examples and the comparative examples was applied to the surface of a polyethylene terephthalate film (released PET 50) having a thickness of 50 μm which was subjected to mold release treatment on the surface. The film thickness after the UV irradiation was 175 μm, and another release PET 50 was bonded to the coated surface.

Next, ultraviolet rays were irradiated from the upper side of the above-mentioned release PET 50 by using a UV irradiation device to prepare an adhesive film in which two release PET 50 layers were laminated via an adhesive. The irradiation of the ultraviolet rays is carried out under the conditions that the cumulative light amount at a wavelength of 300 to 390 nm after passing through the release PET 50 is 1000 mJ/cm ² .

[Method for measuring adhesion]

A piece of release PET 50 constituting the above-mentioned adhesive film was peeled off, and polyethylene terephthalate (PET75) having a thickness of 75 μm was bonded to the surface of the adhesive layer to prepare an adhesive sheet. The above-mentioned adhesive sheet was cut into a width of 25 mm as a test piece used for the measurement of the adhesive force.

Stripping another piece of release PET 50 from the above test piece, on SUS304 stainless steel plate (surface finishing BA (bright heat treatment after cold rolling)), polycarbonate plate, The glass plate was pressed back and forth twice with a 2 kg roller at 23 ° C and 50% RH, and adhered to the respective adherends. After 1 hour of sticking, the 180-degree peel strength was measured in an environment of 23 ° C and 50% RH, and it was used as an adhesive force.

Further, in the case where the adhesive is not obtained and the adhesive is used, the measurement of the 180-degree peel strength is not performed.

[Measurement method of retention force]

The test piece prepared by the same method as the test piece used in the measurement method of the above-mentioned adhesive force is laminated on the mirror-finished stainless steel plate to have an adhesive area of 25 mm × 25 mm and at 23 ° C. In a 50% RH environment, the 2 kg roller was pressed back and forth twice to bond the sheets.

Then, in a test piece adhered to the stainless steel plate, a load of 1 kg was applied in a 0° direction (cutting direction) with respect to the stainless steel plate in an environment of 40° C., and the time until the test piece peeled off from the stainless steel plate was measured. And use this hold time as retention. Moreover, when it hold|maintained after 24 hours, the holding time was 24 hours or more, and the deviation width from the initial pasting position was measured, and it was set together.

Further, in the case where the adhesive is not obtained and the adhesive is used as the adhesive, the measurement of the holding power is not performed.

Furthermore, the abbreviations in Tables 1 to 3 will be described.

"ACMO"; acryloyl morpholine

"BA"; n-butyl acrylate

"(C-1)"; 2-hydroxy-2-methyl-1-phenylpropan-1-one

"(C-2)"; 2,4,6-trimethoxybenzimidyldiphenylphosphine oxide

"M-140"; N-propylene methoxyethyl hexahydrophthalate

"DMAA"; dimethyl methacrylate

"DMAPAA"; dimethylaminopropyl acrylamide

"DMAEA"; dimethylaminoethyl acrylate

"N-VP"; N-vinylpyrrolidone

[Embodiment 8] <Preparation of Resin Composition for UV Curing Adhesive>

In a container equipped with a stirrer, a reflux cooling tube, and a thermometer, 100 parts by mass of the urethane (meth) acrylate resin (A-1) obtained in Synthesis Example 1 and a butyl acrylate were added at a temperature of 80 ° C in the container. 60 parts by mass of the ester and 30 parts by mass of acryloylmorpholine were stirred until uniform. Thereafter, it was cooled to room temperature, and 3 parts by mass of 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2,4,6-trimethylbenzhydryldiphenyl were sequentially added under stirring. 2 parts by mass of phosphine oxide, bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidyl) sebacate ("Tinuvin (registered trademark) 123" BASF Japan (stock)) 1 part by mass, triphenylphosphine 1 part by mass, and 1-bis(2-ethylhexyl)aminomethyl-1,2,4-triazole ("IRGAMET (Trademark Registration) 30" "BASF Japan (stock) system) 0.1 parts by mass, and stirred To even. Then, it was filtered with a 200 mesh metal mesh to obtain a resin composition for an ultraviolet curing adhesive.

[Examples 9 to 11]

A resin composition for an ultraviolet curable adhesive was obtained in the same manner as in Example 5 except that the type and amount of the antioxidant (E) to be used were changed as shown in Table 4.

[Evaluation method of light stability]

One piece of the release PET 50 constituting the adhesive film obtained by the above method was peeled off, the surface of the adhesive layer was adhered to the glass plate, and the other release PET 50 was peeled off as a test piece. The test piece was directly irradiated with ultraviolet rays to the bonding surface in an ultraviolet carbon carbon lamp, a black disk temperature of 63 ° C, and a UV fading meter "U48" (manufactured by Suga Test) in accordance with JIS A 1415, and placed for 150 hours. . Then, the test piece was subjected to a light source C, a field of view of 2°, a “spectrophotometer” CM-5000d (manufactured by Konica Minolta Co., Ltd.), and a yellowness (b*(UV)) due to light was measured in accordance with JIS K 7105.

[Evaluation method of heat-resistant yellowing]

A test piece was obtained in the same manner as described above, and the test piece was exposed to conditions of 85 ° C and 85% RH for 250 hours.

Then, the test piece was subjected to heat generation yellowness (b*) in accordance with JIS K 7105 using a light source C, a field of view of 2°, and a "spectrophotometer" CM-5000d (manufactured by Konica Minolta Sensing Co., Ltd.).

[Evaluation method of rust prevention]

One piece of the release PET 50 constituting the above-mentioned adhesive film was peeled off, and polyethylene terephthalate (PET75) having a thickness of 75 μm was bonded to the surface of the adhesive layer to prepare an adhesive sheet. The above-mentioned adhesive sheet was cut into a size of 40 mm × 50 mm, and used as a test piece for evaluation of rust resistance.

The aforementioned test piece from which another release PET 50 was peeled off was attached to a copper foil, and allowed to stand in an environment of 60 ° C × 90% RH for 150 hours. After that, visually observe the surface of the copper foil, The rust resistance was evaluated as follows.

"○": No rust.

"X": Rusty.

Furthermore, the abbreviations in Table 4 will be described.

"Irgafos 38": bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite

"Irganox PS800FD": bis(dodecyl)-3,3'-thiopropionate

"Irganox1010": pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl) Propionate

[Embodiment 12] (manufacture of laminate)

The resin composition for an ultraviolet curable adhesive obtained in Example 5 was applied in the same manner as in the above method to obtain an adhesive film having a film thickness of 175 μm. Thereafter, a piece of the release PET 50 film was peeled off and bonded to the polycarbonate film.

Next, another release PET film was peeled off and bonded to a glass plate to obtain a laminate.

Claims (13)

A resin composition for an ultraviolet curable adhesive, which comprises an amine urethane obtained by reacting a polyol (a), a polyisocyanate (b), and a hydroxyl group-containing (meth)acrylic compound (c) ( A resin composition for a UV curable adhesive of a methyl acrylate resin (A), a (meth)acrylic monomer (B), and a photopolymerization initiator (C), which is characterized in that: The acrylic monomer (B) contains a nitrogen-containing (meth)acrylic monomer (b-1) which can form a homopolymer having a glass transition temperature of 50 ° C or higher, and a glass transition temperature of -20 ° C or lower can be formed. a homopolymer (meth)acrylic monomer (b-2), and the mass ratio of the (b-1) to the (b-2) is (b-1)/(b-2)= 20/80~60/40; the polyol (a) is a polyether polyol. The resin composition for an ultraviolet curing adhesive according to the first aspect of the invention, wherein the nitrogen-containing (meth)acrylic monomer (b-1) which forms a homopolymer at a glass transition temperature of 50 ° C or higher A nitrogen-containing (meth)acrylic monomer which forms a homopolymer at a glass transition temperature of 55 to 160 °C. The resin composition for an ultraviolet curing adhesive according to the second aspect of the invention, wherein the glass transition temperature is 55 to 160 ° C, and a nitrogen-containing (meth)acrylic monomer capable of forming a homopolymer is selected. From the group consisting of acryloyl morpholine, dimethyl methacrylate, dimethylaminopropyl acrylamide and N-propylene methoxyethyl hexahydrophthalimide More than one type. The resin composition for an ultraviolet curing adhesive according to any one of claims 1 to 3, wherein the photopolymerization initiator (C) is selected from 2-hydroxy-2-methyl- 1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,4,6-trimethylbenzimidyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzene One or more of the group consisting of mercapto)-phenylphosphine oxide. The resin composition for an ultraviolet curable adhesive according to any one of claims 1 to 3, further comprising a light stabilizer (D). The resin composition for an ultraviolet curable adhesive according to any one of claims 1 to 3, which further comprises an antioxidant (E). The ultraviolet curing adhesive as claimed in any one of claims 1 to 3 The resin composition further contains a rust inhibitor (F). A resin composition for an ultraviolet curable adhesive according to claim 5, wherein the light stabilizer (D) is a hindered amine compound. The resin composition for an ultraviolet curing adhesive according to the sixth aspect of the invention, wherein the antioxidant (E) is a phosphorus compound. The resin composition for an ultraviolet curing adhesive according to the seventh aspect of the invention, wherein the rust inhibitor (F) is a triazole compound. An adhesive composition comprising the resin composition for an ultraviolet curable adhesive according to any one of claims 1 to 10. For example, the adhesive of claim 11 is used for optical members. A laminate which is laminated on at least two sides of a layer (i) formed of an adhesive composed of a resin composition for an ultraviolet curing adhesive as disclosed in claims 1 to 10 of the patent application. Layer (ii) consisting of a group selected from the group consisting of a plastic substrate, a flexible printed substrate, a glass substrate, and a substrate on which the indium tin oxide is vapor deposited. One of the substrates in the group is composed.