JP2024029540A - Active energy ray curable adhesive composition - Google Patents

Abstract

An object of the present invention is to provide an active energy ray-curable composition whose cured product has high refraction, excellent adhesiveness to a substrate, and maintains adhesive strength even after an environmental test under high temperature and high humidity conditions. [Solution] The curable component contains the following (A) and (B), the curable component is contained in a proportion of 70% by weight or more in the total amount of the composition, and the curable component contains the following (A) and ( An active energy ray-curable adhesive composition containing B) in a specific proportion and the following (C) in a specific proportion relative to the curable component. (A): Difunctional or higher functional urethane (meth)acrylate (B): Unsaturated compound other than (A), which cures the following (B-1), (B-2), and (B-3)・(B-1): Mono(meth)acrylate having two or more aromatic rings ・(B-2): Hydroxyl group-containing mono(meth)acrylate having no aromatic ring・(B-3): Monofunctional unsaturated compound having one aromatic ring (C): Photoradical polymerization initiator [Selection diagram] None

Description

The present invention relates to an active energy ray-curable adhesive composition that can bond various substrates, preferably plastic films or sheets, by irradiation with active energy rays such as electron beams or ultraviolet rays.
In the following, unless otherwise specified, plastic films or sheets are collectively referred to as "plastic films", and films or sheets are collectively referred to as "films".

Conventionally, ethylene-vinyl acetate copolymers and polyurethane polymers have been used to bond adherends such as plastic films or adherends such as plastic films to adherends made of other materials. A dry lamination method is mainly used in which a solvent-based adhesive composition containing the following is applied to a first thin-layer adherend, dried, and then a second thin-layer adherend is pressure-bonded thereto.
The adhesive composition used in this method generally contains a large amount of solvent in order to uniformly apply the composition, but this results in the volatilization of a large amount of solvent vapor during drying, resulting in toxicity, work safety issues, and Environmental pollution is a problem.
Solvent-free adhesive compositions are being considered as adhesive compositions that can solve these problems.

As solvent-free adhesive compositions, two-component adhesive compositions and adhesive compositions that are cured by active energy rays such as ultraviolet rays or electron beams are widely used.
As a two-component adhesive composition, a so-called polyurethane adhesive composition is used, which mainly uses a polymer having a hydroxyl group at the end as a main ingredient and a polyisocyanate compound having an isocyanate group at the end as a curing agent. However, the composition has the disadvantage that it takes too long to cure.
On the other hand, active energy ray-curable adhesive compositions are attracting attention because of their fast curing speed and excellent productivity.

On the other hand, active energy ray-curable adhesive compositions are also being considered for bonding optical films used in displays and the like.
For example, Patent Document 1 states that (A) 30 to 70% by weight of urethane (meth)acrylate having a number average molecular weight of 10,000 to 40,000; and (B) an ethylenic homopolymer having a glass transition temperature of 60°C or higher; Liquid curable resin compositions containing 30 to 60% by weight of unsaturated monomers are disclosed.
Patent Document 2 describes (A) polyether urethane (meth)acrylate and (B) a monofunctional (meth)acrylate containing at least one aromatic ring and having a refractive index (25° C.) of 1.55 or more. and (C) a high refractive index plasticizer containing at least one aromatic ring and having a refractive index of 1.55 or more.

Japanese Patent Application Publication No. 2004-115757 Japanese Patent Application Publication No. 2014-162853

When optical films used in displays and the like are bonded together using an ultraviolet curable adhesive composition, light reflection occurs due to the difference in refractive index between the optical film and the adhesive.
For example, when the active energy ray-curable adhesive composition of Patent Document 1 is used to bond optical films together, light reflection occurs in the resulting laminate.
On the other hand, in the active energy ray-curable adhesive composition of Patent Document 2, by blending a high refractive index plasticizer with a refractive index of more than 1.55, the resulting cured product has a high refractive index and exhibits initial peeling. The strength was also excellent, and the resulting laminate had no problem with light reflection. However, in the examples, the composition contains a large amount of 30 to 40 parts by weight of a high refractive index plasticizer that does not participate in the polymerization reaction in order to obtain a high refractive index, and the plasticizer may bleed after curing. Therefore, there was a problem in that the resistance to environmental tests at high temperature and high humidity was reduced.

The present inventors have developed an active energy ray-curable composition in which the resulting cured product has a high refraction, excellent adhesion to substrates, and maintains adhesive strength even after environmental tests under high temperature and high humidity conditions. We conducted extensive research to find out.

As a result of intensive studies to solve the above problems, the present inventors discovered that urethane (meth)acrylate, a compound having one (meth)acryloyl group having two or more aromatic rings, and (meth)acrylate having a hydroxyl group. The active energy ray-curable adhesive composition containing a specific proportion of acrylate has a high refractive index, excellent adhesion to substrates, and even adhesive strength after environmental tests under high temperature and high humidity conditions. The present invention has been completed based on the discovery that the same can be maintained.

The present invention is a composition containing the following components (A) and (B) as curable components,
Contains a curable component in a proportion of 70% by weight or more in the total amount of the composition,
Contains the following (A) component and (B) component as curable components,
Contains the following component (A) in a proportion of 5 to 30% by weight and component (B) in a proportion of 70 to 95% by weight in a total of 100% by weight of the curable components,
The present invention relates to an active energy ray-curable adhesive composition containing the following component (C) in a ratio of 0.1 to 5 parts by weight per 100 parts by weight of the curable component.
(A) Component: Urethane (meth)acrylate having two or more (meth)acryloyl groups (B) Component: A compound having an ethylenically unsaturated group other than the (A) component, which is the following (B-1) component , (B-2) component, and (B-3) component,
In 100% by weight of the curable component, the proportion of the following component (B-1) is 30 to 75% by weight, component (B-2) is 10 to 40% by weight, and component (B-3) is 0 to 40% by weight. Component (B-1): Compound having two or more aromatic rings and one (meth)acryloyl group Component (B-2): No aromatic ring, hydroxyl group and one Component (B-3): Compound containing one aromatic ring and one ethylenically unsaturated group (C) Component: Photoradical polymerization initiator

As the component (A), urethane di(meth)acrylate having a weight average molecular weight of 500 to 100,000 is preferable.
Moreover, as the component (A), urethane di(meth)acrylate having a polyester skeleton or a polycarbonate skeleton is preferable.
Further, as the component (A), urethane di(meth)acrylate having no aromatic skeleton is preferable.

As the component (B),
The component (B-1) contains a mono(meth)acrylate having a biphenyl group or a phenoxybenzyl group,
It is preferable that the component (B-2) contains hydroxyalkyl mono(meth)acrylate.
As the biphenyl group-containing mono(meth)acrylate in component (B-1), alkylene oxide-modified phenylphenol acrylate is preferable.

The cured product of the composition preferably has a refractive index greater than 1.54.
As the adherend, a plastic film or sheet is preferred.
The cured product of the composition is a cured product obtained by using two polyethylene terephthalate films as adherends and irradiating ultraviolet rays with a cumulative light intensity of 1000 mJ/cm ² using a metal halide lamp as the light source, which meets JIS-6854-3. It is preferable that the specified T-peel strength (peel speed: 200 mm/min) is 15 N/25 mm or more.

The present invention also relates to a method for producing a laminate in which the above-described active energy ray-curable adhesive composition is applied to an adherend and bonded together, and active energy rays are irradiated from either side of the adherend. related.

According to the active energy ray-curable adhesive composition of the present invention, the cured product obtained has a high refraction, excellent adhesiveness to substrates, particularly excellent adhesiveness to plastic substrates, and furthermore, Maintains adhesion even after environmental testing under these conditions.

The present invention will be explained in detail below.
In this specification, acrylate and/or methacrylate will be referred to as (meth)acrylate, acryloyl group and/or methacryloyl group will be referred to as (meth)acryloyl group, and acrylic acid and/or methacrylic acid will be referred to as (meth)acrylic acid. .
In addition, the curable component is a component having one or more ethylenically unsaturated groups that is cured by active energy rays, and means the (A) component and the (B) component, and when it includes the (D) component described below. means (A) component, (B) component, and (D) component.

The present invention is a composition comprising component (A) and component (B) described below as curable components,
Contains a curable component in a proportion of 70% by weight or more in the total amount of the composition,
Containing the component (A) in a proportion of 5 to 30% by weight and the component (B) in a proportion of 70 to 95% by weight in a total of 100% by weight of the curable components,
The present invention relates to an active energy ray-curable adhesive composition containing the component (C) in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the curable component.
Component (A), component (B), component (C), other components, active energy ray-curable adhesive composition, and method of use will be described below.

1. Component (A) Component (A) is a urethane (meth)acrylate having two or more (meth)acryloyl groups.
As component (A), various urethane (meth)acrylates can be used, and specific examples include urethane (meth)acrylates having a polyester skeleton, a polyether skeleton, or a polycarbonate skeleton.
Among these, urethane (meth)acrylates having a polyester skeleton or a polycarbonate skeleton are preferred because the obtained cured product has excellent adhesive strength under high temperature and high humidity conditions.
Furthermore, as component (A), non-aromatic urethane (meth)acrylate having no aromatic skeleton, so-called non-yellowing urethane (meth)acrylate, is preferable because it can suppress discoloration of the cured product.
As component (A), both oligomers and polymers can be used, preferably those having a weight average molecular weight of 500 to 100,000, more preferably 3,000 to 70,000, particularly preferably 5,000. ~50,000.
In the present invention, the weight average molecular weight is a value obtained by converting the molecular weight measured by gel permeation chromatography into polystyrene.

Component (A) is more specifically a polyol, a reaction product of an organic polyisocyanate and a hydroxyl group-containing (meth)acrylate, and a reaction product of an organic polyisocyanate and a hydroxyl group-containing (meth)acrylate (so-called urethane adduct). can be mentioned.
As component (A), a reaction product of a polyol, an organic polyisocyanate, and a hydroxyl group-containing (meth)acrylate is preferable, and a compound obtained by reacting a polyol and an organic polyisocyanate reaction product with a hydroxyl group-containing (meth)acrylate is preferable. preferable.
In addition, as component (A), urethane (meth)acrylate having two (meth)acryloyl groups (hereinafter also referred to as bifunctional urethane (meth)acrylate) is used. ], and more preferably a bifunctional urethane (meth)acrylate obtained by reacting a hydroxyl group-containing (meth)acrylate with a reaction product of a diol having a polyester, polyether or polycarbonate skeleton and an organic diisocyanate. .

As the polyol, diols having a polyester skeleton, diols having a polyether skeleton, and diols having a polycarbonate skeleton are preferred.
Examples of polyols having a polyester skeleton include esterification products of a diol component such as a low molecular weight diol or polycaprolactone diol and an acid component such as a dibasic acid or its anhydride.
Examples of low molecular weight diols include ethylene glycol, propylene glycol, cyclohexanedimethanol, 3-methyl-1,5-pentanediol, and 1,6-hexanediol.
Examples of the dibasic acid or its anhydride include adipic acid, succinic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, terephthalic acid, and anhydrides thereof.
Examples of polyether polyols include polyethylene glycol, polypropylene glycol, polyetramethylene glycol, and the like.
Examples of polycarbonate polyols include reaction products of the aforementioned low molecular weight diols or/and bisphenols such as bisphenol A, and dialkyl carbonate esters such as ethylene carbonate and dibutyl carbonate.

Examples of the organic polyisocyanate include tolylene diisocyanate, 1,6-hexane diisocyanate, 4,4'-diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, 1,6-hexane diisocyanate trimer, hydrogenated tolylene diisocyanate, and hydrogenated 4-diisocyanate. , 4'-diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, paraphenylene diisocyanate, tolylene diisocyanate dimer, 1,5-naphthalene diisocyanate, hexamethylene diisocyanate interadduct, 4,4'-dicyclohexylmethane diisocyanate , trimethylolpropane tris(tolylene diisocyanate) adduct, and isophorone diisocyanate.
Further, the organic polyisocyanate is preferably an organic diisocyanate.

Examples of hydroxyl group-containing (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxypentyl (meth)acrylate, hydroxyhexyl (meth)acrylate, and hydroxyl group-containing (meth)acrylate. Hydroxyalkyl (meth)acrylates such as octyl (meth)acrylate; hydroxyl group-containing polyol poly(meth)acrylates such as pentaerythritol tri, di, or mono(meth)acrylate, and trimethylolpropane di- or mono(meth)acrylate; Can be mentioned.
As the hydroxyl group-containing (meth)acrylate, hydroxyalkyl (meth)acrylate is preferred.

(A) Component can be produced by following conventional methods,
1) In the presence of a urethanization catalyst, a polyol and an organic polyisocyanate are heated, stirred, and subjected to an addition reaction to produce a prepolymer having an isocyanate.Hydroxyalkyl (meth)acrylate is added to this, and heated and stirred to cause an addition reaction. and 2) a production method in which a polyol, an organic polyisocyanate, and a hydroxyalkyl (meth)acrylate are heated and stirred in the presence of a urethanization catalyst.
As component (A), those obtained by the manufacturing method 1) above are preferred.
Examples of the urethanization catalyst include tin-based catalysts such as dibutyltin dilaurate, iron-based catalysts such as tris(acetylacetonato)iron, and zinc-based catalysts such as bis(acetylacetonato)zinc.

As component (A), non-aromatic urethane (meth)acrylate without an aromatic skeleton is used because it has particularly excellent adhesive strength under high humidity and the adhesive does not become discolored over time after curing. Preferably, non-aromatic urethane di(meth)acrylate is more preferable.
Specific examples of non-aromatic urethane (meth)acrylates include urethane (meth)acrylates produced from non-aromatic polyols and non-aromatic polyisocyanates.
As the non-aromatic polyol, non-aromatic polyester polyols and polycarbonate polyols are preferred in terms of less coloring after moist heat.

The content ratio of component (A) and component (B) is preferably 5 to 30% by weight of component (A) and 70 to 95% by weight of component (B) in 100% by weight of the total of the curable components. The component (A) is 5 to 20% by weight, and the component (B) is 90 to 80% by weight. If the content of component (A) is less than 5% by weight or if the content of component (B) exceeds 95% by weight, the peel strength will decrease, and if the content of component (A) exceeds 30% by weight. Alternatively, if the content of component (B) is less than 70% by weight, the refractive index will decrease.

2. (B) Component Component (B) is a compound having an ethylenically unsaturated group other than component (A), and includes the following components (B-1), (B-2), and (B-3). including;
In 100% by weight of the curable component, the proportion of the following component (B-1) is 30 to 75% by weight, component (B-2) is 10 to 40% by weight, and component (B-3) is 0 to 40% by weight. It is a compound containing .
・Component (B-1): A compound that has two or more aromatic rings and one (meth)acryloyl group. ・Component (B-2): A compound that has no aromatic ring, a hydroxyl group, and one (meth)acryloyl group. Meta) Compound having an acryloyl group/Component (B-3): Compound containing one aromatic ring and one ethylenically unsaturated group Below, components (B-1) to (B-3) will be explained. do.

2-1. (B-1) Component
Component (B-1) is a compound having two or more aromatic rings and one (meth)acryloyl group.
Component (B-1) is a component that can lower the viscosity of the composition, prevent crystallization of the composition, and impart a high refractive index to the cured product.

As component (B-1), various compounds can be used as long as they have two or more aromatic rings and one (meth)acryloyl group.
Examples of the functional group having two or more aromatic rings in component (B-1) include p-cumylphenyl group, biphenyl group, phenoxybenzyl group, naphthyl group, and fluorenyl group.

Specific examples of mono(meth)acrylates having p-cumylphenyl groups include mono(meth)acrylates represented by the following formula (1).

[In formula (1), R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group, and l represents a number from 0 to 4. ]
l in formula (1) represents the number of alkylene oxides added, and means the average number of additions per molecule.

Specific examples of the compound of formula (1) include p-cumylphenyl (meth)acrylate and p-cumylphenoxyethyl (meth)acrylate.

In the compound of formula (1), R ₁ is preferably a hydrogen atom because good curability can be obtained. Further, l is preferably 0 to 2, since the refractive index of the obtained cured product will be higher and the viscosity of the composition can be kept low.

Among these compounds, p-cumylphenyl acrylate and p-cumylphenoxyethyl acrylate are preferred because they are liquid at room temperature, easy to handle, have a high refractive index, and are easily available.

Specific examples of mono(meth)acrylates having a biphenyl group include mono(meth)acrylates represented by the following formula (2).

[In formula (2), R ₃ and R ₄ each independently represent a hydrogen atom or a methyl group, and m represents a number from 0 to 4. ]
m in formula (2) represents the number of alkylene oxides added, and means the average number of additions per molecule.

Specific examples of the compound of formula (2) include phenylphenyl (meth)acrylates such as o-phenylphenyl (meth)acrylate, m-phenylphenyl (meth)acrylate, and p-phenylphenyl (meth)acrylate; Also, o-phenylphenoxyethyl (meth)acrylate, o-phenylphenoxydiethylene glycol (meth)acrylate, m-phenylphenoxyethyl (meth)acrylate, m-phenylphenoxydiethylene glycol (meth)acrylate, p-phenylphenoxyethyl (meth)acrylate Acrylates, and alkylene oxide-modified phenylphenol (meth)acrylates such as phenylphenoxydiethylene glycol (meth)acrylates such as p-phenylphenoxydiethylene glycol (meth)acrylates.

Among these compounds, o-phenylphenyl (meth)acrylate where m=0 and o-phenylphenoxyethyl (meth)acrylate where m=1 are preferred because they are liquid at room temperature, easy to handle, and readily available.

Specific examples of mono(meth)acrylates having a phenoxybenzyl group include phenoxybenzyl (meth)acrylates such as 3-phenoxybenzyl (meth)acrylate.

Examples of (meth)monoacrylates having a naphthyl group include naphthyl (meth)acrylate, 1-naphthylmethyl (meth)acrylate, and hydroxynaphthyl (meth)acrylate.

Examples of (meth)monoacrylates having a fluorenyl group include fluorenyl (meth)acrylate, 9-fluorenylmethylacrylate (9-acryloyloxymethylfluorene), and hydroxyfluorenyl (meth)acrylate.

Among the aforementioned compounds, mono(meth)acrylate having a biphenyl group or phenoxybenzyl group is preferable as component (B-1) from the viewpoint of easy availability and low viscosity. As the mono(meth)acrylate having a biphenyl group, alkylene oxide-modified phenylphenol acrylate is preferable, and alkylene oxide-modified o-phenylphenol acrylate is more preferable. As the mono(meth)acrylate having a phenoxybenzyl group, phenoxybenzyl acrylate is preferred, and 3-phenoxybenzyl acrylate is more preferred.

The content of component (B-1) is 30 to 75% by weight, preferably 30 to 60% by weight, based on 100% by weight of the curable component. If the content of component (B-1) is less than 30% by weight, the refractive index of the cured product will decrease, and if it exceeds 75% by weight, the peel strength of the cured product will decrease.

2-2. (B-2) Component
Component (B-2) is a compound that does not have an aromatic ring and has a hydroxyl group and one (meth)acryloyl group.
As component (B-2), various compounds can be used as long as they do not have an aromatic ring and have a hydroxyl group and one (meth)acryloyl group.
Specific examples of component (B-2) include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Hydroxyalkyl mono(meth)acrylate, as well as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, polytetramethylene glycol mono(meth)acrylate, polyethylene glycol - polypropylene glycol mono(meth)acrylate, polyethylene glycol - Examples include polyalkylene glycol mono(meth)acrylates such as polytetramethylene glycol mono(meth)acrylate and polypropylene glycol-polytetramethylene glycol mono(meth)acrylate.

The content of component (B-2) is 10 to 40% by weight, preferably 15 to 30% by weight, based on 100% by weight of the curable component. If the content of component (B-2) is less than 10% by weight, the peel strength of the cured product will decrease, and if it exceeds 40% by weight, the refractive index of the cured product will decrease.

2-3. (B-3) Component
Component (B-3) is a compound containing one aromatic ring and one ethylenically unsaturated group.
As component (B-3), various compounds can be used as long as they contain one aromatic ring and one ethylenically unsaturated group.
Examples of ethylenically unsaturated groups include (meth)acryloyl groups and vinyl groups.

Specific examples of compounds having a (meth)acryloyl group include phenyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, (meth)acrylate of alkylene oxide-modified phenol, and alkylene oxide-modified cresol. (meth)acrylates of nonylphenol modified with alkylene oxide, (meth)acrylates of alkylene oxide modified tribromophenol, and the like.
In the alkylene oxide adduct, examples of the alkylene oxide include ethylene oxide and propylene oxide.

Specific examples of compounds having a vinyl group include aromatic vinyl compounds such as styrene and vinyltoluene.

The content of component (B-3) is 0 to 40% by weight, preferably 0 to 30% by weight, based on 100% by weight of the curable component. If the content of component (B-3) exceeds 40% by weight, the peel strength of the cured product will decrease.

3. Component (C) Component (C) is a photoradical polymerization initiator. Component (C) is a compound that generates radicals by irradiation with active energy rays and initiates the polymerization of components (A), (B), and (D) described later, which are compounds having ethylenically unsaturated groups. be.

Specific examples of component (C) include benzyl dimethyl ketal, benzyl, benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane. 1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1- on, oligo[2-hydroxy-2-methyl-1-[4-1-(methylvinyl)phenyl]propanone, 2-hydroxy-1-[4-[4-(2-hydroxy-2-methyl-propionyl)] -benzyl]-phenyl]-2-methylpropan-1-one, 2-methyl-1-[4-(methylthio)]phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino -1-(4-morpholinophenyl)butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one , ADEKA Optomer N-1414 [manufactured by ADEKA Corporation], aromatic ketone compounds such as phenylglyoxylic acid methyl ester, ethyl anthraquinone, and phenanthrenequinone;
Benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, 4-phenylbenzophenone, 4-(methylphenylthio)phenylphenylmethane, methyl-2-benzophenone, 1- [4-(4-Benzoylphenylsulfanyl)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis Benzophenones such as (diethylamino)benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone and 4-methoxy-4'-dimethylaminobenzophenone Compound;
Bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl-(2,4,6-trimethylbenzoyl)phenylphosphine and bis(2, Acyl phosphine oxide compounds such as 6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide;
Thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 1-chloro-4-propylthioxanthone, 3-[3,4-dimethyl-9-oxo-9H-thioxanthon-2-yl]oxy]- Thioxanthone compounds such as 2-hydroxypropyl-N,N,N-trimethylammonium chloride and fluorothioxanthone;
Acridone compounds such as acridone and 10-butyl-2-chloroacridone;
1,2-octanedione 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl] -1-(O-acetyloxime) and other oxime esters, 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(m-methoxy) phenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-phenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p- methoxyphenyl)-4,5-diphenylimidazole dimer, 2,4-di(p-methoxyphenyl)-5-phenylimidazole dimer and 2-(2,4-dimethoxyphenyl)-4,5-diphenyl Examples include 2,4,5-triarylimidazole dimers such as imidazole dimers; and acridine derivatives such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane.

Among the above-mentioned compounds, aromatic ketone compounds, acylphosphine oxide compounds, and thioxanthone compounds are preferred because they can provide excellent curability and adhesive properties of the composition.

As component (C), the above-mentioned compounds may be used alone or in combination of two or more.

The content of component (C) is 0.1 to 5 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the total amount of curable components.
If the proportion of component (C) is less than 0.1 part by weight, the active energy ray curability of the composition will be insufficient and the adhesiveness will decrease, while if it exceeds 5 parts by weight, the inside of the adhesive layer Curability becomes poor and adhesiveness decreases.

4. Other Components The active energy ray-curable adhesive composition of the present invention has the above-mentioned components (A) to (C) as essential components, but various other components can be added depending on the purpose. .

Other components include compounds other than components (A) and (B) having ethylenically unsaturated groups [hereinafter referred to as "component (D)"]. ], ultraviolet absorbers, polymerization inhibitors, silane coupling agents, antioxidants, plasticizers, and surface modifiers.

4-1． Component (D) Component (D) is a compound other than components (A) and (B) that has an ethylenically unsaturated group.
Examples of the component (D) include compounds other than the component (B) having one ethylenically unsaturated group, and compounds other than the components (A) and (B) having an ethylenically unsaturated group.

Examples of compounds other than component (B) having one ethylenically unsaturated group include compounds having one (meth)acryloyl group in the molecule, vinyl compounds, and allyl compounds.
Compounds other than component (B) having one ethylenically unsaturated group are blended for the purpose of adjusting physical properties such as the viscosity and curability of the composition and the adhesiveness and flexibility of the cured product.

Specific examples of compounds having one (meth)acryloyl group in the molecule include (meth)acrylic acid, (meth)acrylic acid dimer, 2-(meth)acryloyloxyethylsuccinic acid, and 2-(meth)acrylic acid. Compounds having a carboxy group and a (meth)acryloyl group, such as acryloyloxyethyl phthalic acid, 2-(meth)acryloyloxyethylhexahydrophthalic acid, and ω-carboxypolycaprolactone (meth)acrylate;
Methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, amyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, Pentyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, Decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate, alkyl (meth)acrylate having 12 to 13 carbon atoms, cetyl (meth)acrylate, stearyl ( aliphatic (meth)acrylates such as meth)acrylate, isostearyl (meth)acrylate, and isomyristyl (meth)acrylate;
Methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, 2-ethylhexyl carbitol (meth)acrylate, butoxyethyl (meth)acrylate, methoxyethylene glycol (meth)acrylate, ethoxy Alkoxyalkyl (meth)acrylates such as diethylene glycol (meth)acrylate, ethoxyethyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, and methoxypolypropylene glycol (meth)acrylate;
Bornyl (meth)acrylate, isobornyl (meth)acrylate, tricyclodecanyl (meth)acrylate, dicyclopentanyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate, cyclohexyl (meth)acrylate, t-butylcyclohexyl ( meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, dicyclopentenyl (meth)acrylate, adamantyl (meth)acrylate, tricyclodecane (meth)acrylate, and Alicyclic (meth)acrylates such as dicyclopentenyloxyethyl (meth)acrylate;
Tetrahydrofurfuryl (meth)acrylate, and (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate cyclic ether group-containing (meth)acrylate;
Carbonate group-containing (meth)acrylates such as glycerin carbonate (meth)acrylate;
N-(meth)acryloyloxyethylhexahydrophthalimide, 2-(1,2-cyclohexa-1-enedicarboximide)ethyl(meth)acrylate, Fancryl FA-502A [manufactured by Showa Denko Materials Co., Ltd.], etc. and phosphoric acid (meth)acrylates such as 2-(meth)acryloyloxyethyl acid phosphate.

Specific examples of vinyl compounds include heterocyclic vinyl compounds such as vinyl imidazole and vinylpyridine; and n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, 2-hydroxyethyl vinyl ether, cyclohexanedimethanol monovinyl ether, diethylene glycol mono Examples include vinyl ethers such as vinyl ether, 4-hydroxybutyl vinyl ether, cyclohexyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, lauryl vinyl ether, cetyl vinyl ether, and 2-ethylhexyl vinyl ether.
Specific examples of allyl compounds include monofunctional allyl compounds having one allyl group such as allyl alcohol.

Compounds other than components (A) and (B) having two or more ethylenically unsaturated groups include compounds having two or more (meth)acryloyl groups in the molecule [hereinafter referred to as "polyfunctional (meth)acrylates"] ], compounds having two or more vinyl groups in the molecule [hereinafter referred to as "polyfunctional vinyl compounds"], and the like. Furthermore, various molecular weights can be selected, and they may be monomers, oligomers, or polymers.
Compounds other than components (A) and (B) having two or more ethylenically unsaturated groups are blended for the purpose of adjusting physical properties such as adhesiveness and flexibility of the cured product.

Specific examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1 , 6-hexanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate and 1,9 - di(meth)acrylates of aliphatic diols, such as nonanediol di(meth)acrylates;
Diethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, and polypropylene glycol di(meth)acrylate polyalkylene glycol di(meth)acrylates such as;
Di(meth)acrylates of alicyclic diols such as cyclohexane dimethylol di(meth)acrylate and tricyclodecane dimethyloldi(meth)acrylate;
The esterification reaction product of neopentyl glycol, hydroxypivalic acid, and (meth)acrylic acid (hereinafter referred to as "neopentyl hydroxypivalate glycol di(meth)acrylate"), caprolactone-modified neopentyl glycol di(meth)acrylate hydroxypivalate, ) acrylate;
Di(meth)acrylate of alkylene oxide adduct of bisphenol compound such as di(meth)acrylate of bisphenol A alkylene oxide adduct;
Di(meth)acrylates of hydrogenated bisphenol compounds such as di(meth)acrylates of hydrogenated bisphenol A;
Di(meth)acrylate of isocyanuric acid alkylene oxide adduct, tri(meth)acrylate of isocyanuric acid alkylene oxide adduct, di(meth)acrylate of caprolactone-modified isocyanuric acid alkylene oxide adduct, caprolactone-modified isocyanuric acid alkylene oxide adduct Poly(meth)acrylates of isocyanuric acid alkylene oxide adducts such as tri(meth)acrylates;
Polyol poly(meth)acrylates such as trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tri- or tetra(meth)acrylate, dipentaerythritol penta- or hexa(meth)acrylate;
Tri(meth)acrylate of trimethylolpropane alkylene oxide adduct, tetra(meth)acrylate of ditrimethylolpropane alkylene oxide adduct, tri- or tetra(meth)acrylate of pentaerythritol alkylene oxide adduct, dipentaerythritol alkylene oxide adduct Poly(meth)acrylates of polyol alkylene oxide adducts such as penta- or hexa(meth)acrylates:
Urethane (meth)acrylate;
Examples include epoxy (meth)acrylate; and polyester (meth)acrylate.
The polyester (meth)acrylate may be a dendrimer type (meth)acrylate.
In the alkylene oxide adduct, examples of the alkylene oxide include ethylene oxide and propylene oxide.

Specific examples of hydroxyl group-containing polyfunctional (meth)acrylates include trimethylolpropane mono- or di-(meth)acrylate, pentaerythritol mono-, di- or tri-(meth)acrylate, and di-trimethylolpropane mono-, di- or tri-(meth)acrylate. Mention may be made of acrylates and dipentaerythritol mono-, di-, tri-, tetra- or penta(meth)acrylates, epoxy(meth)acrylates.

Epoxy (meth)acrylate is a compound obtained by adding (meth)acrylic acid to an epoxy resin, and is described in the literature "UV/EB Curing Materials" [CMC Co., Ltd., published in 1992], pages 74-75. Examples include compounds such as those described.

Examples of the epoxy resin include aromatic epoxy resins and aliphatic epoxy resins.
Specific examples of the aromatic epoxy resin include resorcinol diglycidyl ether; di- or polyglycidyl ether of bisphenol A, bisphenol F, bisphenol S, bisphenol fluorene or its alkylene oxide adduct; phenol novolak type epoxy resin and cresol novolak type epoxy resin. Examples include novolac type epoxy resins such as epoxy resins; glycidyl phthalimide; o-phthalic acid diglycidyl ester;
In addition to these, there are also two chapters of the literature "Epoxy Resins - Recent Advances" (Shokodo, published in 1990), and the literature "Kobunshi Processing" Special Volume 9, Volume 22 Extra Issue Epoxy Resins [Kobunshi Publishing Co., Ltd., Compounds such as those described on pages 4 to 6 and pages 9 to 16 of ``Published in 1972'' can be mentioned.

Specific examples of aliphatic epoxy resins include diglycidyl ethers of alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol; diglycidyl ethers of polyethylene glycol and polypropylene glycol, etc. diglycidyl ether of polyalkylene glycol; diglycidyl ether of neopentyl glycol, dibromoneopentyl glycol and its alkylene oxide adduct; di- or triglycidyl ether of trimethylolethane, trimethylolpropane, glycerin and its alkylene oxide adduct; and polyglycidyl ethers of polyhydric alcohols such as di-, tri- or tetraglycidyl ethers of pentaerythritol and its alkylene oxide adducts; di- or polyglycidyl ethers of hydrogenated bisphenol A and its alkylene oxide adducts; diglycidyl tetrahydrophthalate Ethers include hydroquinone diglycidyl ether and the like.
In addition to these, compounds described on pages 3 to 6 of the above-mentioned document "Polymer Processing" special edition of epoxy resins can be mentioned.

In addition to these aromatic epoxy resins and aliphatic epoxy resins, there are epoxy compounds having a triazine nucleus in the skeleton, such as TEPIC [Nissan Chemical Co., Ltd.], Denacol EX-310 [Nagase Kasei Co., Ltd.], etc. Compounds such as those described on pages 289 to 296 of the above-mentioned literature "Polymer Processing" special edition of epoxy resins may be mentioned.
In the above, the alkylene oxide of the alkylene oxide adduct is preferably ethylene oxide, propylene oxide, or the like.

Examples of the allyl compound include monofunctional allyl compounds such as allyl alcohol, and polyfunctional allyl compounds such as diallyl phthalate, triallyl isocyanurate, and triallyl cyanurate.

In addition to these, compounds such as those described on pages 53 to 56 of the document "Latest UV Curing Technology" [Printing Information Association Co., Ltd., published in 1991] may be mentioned.

As component (D), polyethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1, 6-hexanediol di(meth)acrylate, neopentyl glycol hydroxypivalic acid di(meth)acrylate, caprolactone-modified neopentyl glycol hydroxypivalic acid di(meth)acrylate, and bisphenol A-type epoxy(meth)acrylate are preferred, and caprolactone-modified neopentyl glycol di(meth)acrylate is preferred. Pentyl glycol hydroxypivalic acid di(meth)acrylate (the amount of caprolactone modification is preferably 1 to 10 mol) and bisphenol A type epoxy (meth)acrylate are preferred.

The content of component (D) in the curable component is preferably 1 to 30% by weight, more preferably 2 to 20% by weight based on 100% by weight of the total amount of the curable component. By setting the proportion of component (D) to 1% by weight or more, the viscosity can be adjusted to be easy to coat, and excellent adhesive strength and heat resistance can be obtained. By setting the proportion of component (D) to 30% by weight or less, the cured product can have a high refractive index. rate.

4-2. Ultraviolet absorber The composition of the present invention can improve adhesive strength by containing an ultraviolet absorber. Although the reason is unknown, it is presumed that by blocking ultraviolet rays in the low wavelength range, the curing speed is suppressed and the residual stress at the adhesive interface is reduced.

Examples of the ultraviolet absorber include triazine ultraviolet absorbers such as TINUVIN400, TINUVIN405, TINUVIN460, and TINUVIN479 manufactured by BASF, and benzotriazole ultraviolet absorbers such as TINUVIN900, TINUVIN928, and TINUVIN1130.

The content ratio of the ultraviolet absorber may be appropriately set depending on the purpose, and is preferably 0.1 to 5 parts by weight, more preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the total amount of curable components. It is. When the content is 0.1 parts by weight or more, the adhesive strength can be increased, and when the content is 5 parts by weight or less, deterioration in curability can be suppressed.

4-3. Polymerization inhibitor Examples of the polymerization inhibitor include organic polymerization inhibitors, inorganic polymerization inhibitors, and organic salt polymerization inhibitors.
Specific examples of organic polymerization inhibitors include hydroquinone, tert-butylhydroquinone, hydroquinone monomethyl ether, 2,6-di-tert-butyl-4-methylphenol, 2,4,6-tri-tert-butylphenol, 4- Phenol compounds such as tert-butylcatechol, quinone compounds such as benzoquinone, galvinoxyl, 2,2,6,6-tetramethylpiperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1 Examples include stable radicals such as -oxyl, phenothiazine, N-nitroso-N-phenylhydroxylamine ammonium, and the like.
Specific examples of inorganic polymerization inhibitors include copper chloride, copper sulfate, and iron sulfate.
Specific examples of organic salt-based polymerization inhibitors include nitroso compounds such as N-nitroso-N-phenylhydroxylamine aluminum salt, ammonium N-nitrosophenylhydroxylamine, and copper dibutyldithiocarbamate.

Among these, stable radicals and nitroso compounds are preferred because they cause little coloring of the adhesive, prevent thickening and gelation of the composition, and improve storage stability.
The content ratio of the polymerization inhibitor may be appropriately set depending on the purpose, and is preferably 0.0001 to 1 part by weight, more preferably 0.0005 to 0.5 parts by weight, based on 100 parts by weight of the total amount of curable components. Parts by weight. When the content is 0.0001 part by weight or more, the thermal stability and photostability of the composition can be improved, and when the content is 1 part by weight or less, the photocurability of the composition is excellent. I can do it.

4-4. Silane coupling agent Specific examples of the silane coupling agent include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acrylic Roxypropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3 -Aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-amino Examples include propyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 3-mercaptopropyltrimethoxysilane. These may be used alone or in combination of two or more.

4-5． Antioxidants Examples of antioxidants include phenolic antioxidants, phosphorus antioxidants, and sulfur antioxidants.
Specific examples of phenolic antioxidants include hindered phenols such as di-t-butylhydroxytoluene. Commercially available products include AO-20, AO-30, AO-40, AO-50, AO-60, AO-70, and AO-80 manufactured by ADEKA Corporation.
Specific examples of phosphorus-based antioxidants include phosphines such as trialkylphosphines and triarylphosphines, trialkyl phosphites, and triaryl phosphites. Commercially available derivatives of these include, for example, ADEKA STAB PEP-4C, PEP-8, PEP-24G, PEP-36, HP-10, 260, 522A, 329K, 1178, 1500, 135A, 3010 manufactured by ADEKA Co., Ltd. etc.
Specific examples of sulfur-based antioxidants include thioether-based compounds, and commercially available products include ADEKA Corporation's AO-23, AO-412S, and AO-503A.
These may be used alone or in combination of two or more. Preferred combinations of these antioxidants include combinations of phenolic antioxidants and phosphorus antioxidants, and combinations of phenolic antioxidants and sulfur antioxidants.

4-6. Plasticizer The composition of the present invention may contain a plasticizer, if necessary, for the purpose of imparting flexibility to improve adhesive strength and suppress cracking during curing.
Plasticizers include phthalate esters such as phenylphenol, dimethyl phthalate, diethyl phthalate and dioctyl phthalate; fats such as dimethyl adipate, dibutyl adipate, dioctyl adipate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate and diethyl succinate. aliphatic polybasic acid esters such as dibasic acid esters and tributyl acetyl citrate; orthophosphoric acid esters such as trimethyl phosphate, triethyl phosphate, triphenyl phosphate and tricresyl phosphate; glyceryl triacetate and 2-ethylhexyl Acetic acid esters such as acetate; phosphite esters such as triphenyl phosphite and dibutylhydrodiene phosphite; natural resins and their derivatives such as rosin resins and terpene resins; and polyesters and acrylic polymers (e.g. Examples include inert compounds such as Alphon UP-1000 (manufactured by Toagosei Co., Ltd.), polyethers, and petroleum resins.

The content of the plasticizer may be appropriately set depending on the purpose, but it is preferably 1 to less than 30% by weight, more preferably 5 to 20% by weight in the composition.

4-7． Surface modifiers Surface modifiers include surface conditioning agents, surfactants, leveling agents, antifoaming agents, slippery agents, antifouling agents, etc. These known surface modifiers are used. can do.
Among these, silicone-based surface modifiers and fluorine-based surface modifiers are preferably mentioned.
Specific examples include silicone polymers and oligomers having silicone chains and polyalkylene oxide chains, silicone polymers and oligomers having silicone chains and polyester chains, and fluorine polymers having perfluoroalkyl groups and polyalkylene oxide chains. and oligomers, and fluorine-based polymers and oligomers having perfluoroalkyl ether chains and polyalkylene oxide chains.
Furthermore, in order to improve durability, a surface modifier having an ethylenically unsaturated group, preferably a (meth)acryloyl group, in the molecule may be used. These may be used alone or in combination of two or more.

5. Active Energy Ray Curable Adhesive Composition The present invention is an active energy ray curable adhesive composition containing the components (A) to (C) in specific proportions.
The composition can be produced by stirring and mixing the components (A) to (C) and, if necessary, other components according to a conventional method.
In this case, heating can be performed if necessary. The heating temperature may be appropriately set depending on the composition, substrate, purpose, etc. used, but is preferably 30 to 80°C.

The proportion of the curable component in the composition must be 70% by weight or more, preferably 70 to 99.9% by weight, more preferably 90 to 99% by weight. .
If the proportion of the curable component in the composition is less than 70% by weight, the adhesive strength will decrease due to bleeding or excessive plasticization due to non-curable components.

The viscosity of the composition is preferably 10 to 1,000 mPa·s in terms of excellent coating properties on substrates.

The composition of the present invention preferably has a cured product having a refractive index of more than 1.54, preferably 1.55 or more. When the refractive index of the cured product exceeds 1.54, reflection caused by the difference in refractive index between the cured composition and the optical film base material can be prevented.
In the present invention, the refractive index of the cured product means a value measured at 25° C. at the D line of 589.3 nm using an Abbe refractometer.

The composition of the present invention is a cured product obtained by using two polyethylene terephthalate films as adherends and irradiating ultraviolet rays with a cumulative light intensity of 1000 mJ/cm ² using a metal halide lamp as a light source, in accordance with JIS-6854-3. It is preferable that the specified T-peel strength (peel speed: 200 mm/min) is 15 N/25 mm or more.

6. Method of Use The composition of the present invention can be used for adhesion of various base materials (adherents), such as adhesion between plastic films or sheets (hereinafter simply referred to as "plastic films"), and adhesion between plastic films and sheets. It can be preferably used for adhesion of various base materials other than (hereinafter referred to as other base materials),
As a specific example, after applying it to a base material (adherend), it is bonded to another base material (adherend), and active energy rays are irradiated from either side of the base material (adherend). Examples include methods.
In addition, in the present invention, when simply written as "base material", it means a general term for plastic films and other base materials.
Other base materials include paper and metal.

Plastic films include hydrophilic plastic films and hydrophobic plastics.
Specific examples of hydrophilic plastic films include polyvinyl alcohol films, and cellulose ester films such as triacetyl cellulose films and diacetyl cellulose films.
Specific examples of hydrophobic plastic films include polycarbonate films, polyethylene terephthalate films, polyethylene naphthalate films, acrylic films, acrylic/styrene films, aliphatic polyamide (nylon) films, aromatic polyamide films, Polyurethane film, polyimide film, ethylene-vinyl acetate copolymer film, polyvinyl chloride film, polyvinylidene chloride film, polyethylene film, polypropylene film, polycycloolefin film, polystyrene film, ABS film , and chlorinated polypropylene films.
Examples of the paper include imitation paper, high-quality paper, kraft paper, art coated paper, caster coated paper, pure white roll paper, parchment paper, waterproof paper, glassine paper, and corrugated paper.
Examples of the metal foil include aluminum foil.

Coating to the substrate can be done using conventionally known methods such as natural coater, knife belt coater, floating knife, knife over roll, knife on blanket, spray, dip, kiss roll, squeeze roll, reverse roll, and air blade. , curtain flow coater, comma coater, gravure coater, microgravure coater, die coater and curtain coater.
Further, the coating thickness of the composition of the present invention may be selected depending on the substrate used and the application, but is preferably 0.1 to 100 μm, more preferably 1 to 25 μm.

Examples of active energy rays include visible light, ultraviolet rays, X-rays, and electron beams, but ultraviolet rays are preferred because inexpensive equipment can be used.
Various light sources can be used for curing with ultraviolet rays, such as pressurized or high-pressure mercury lamps, metal halide lamps, xenon lamps, electrodeless discharge lamps, carbon arc lamps, and LEDs. Among these, high-pressure mercury lamps and metal halide lamps are preferred, and metal halide lamps are particularly preferred. The amount of ultraviolet ray irradiation is preferably 200 to 2,000 mJ/cm ² in the UV-A region (near 365 nm), more preferably 300 to 1,500 mJ/cm ² .

In the case of curing with an electron beam, various EB irradiation devices can be used, such as Cockroft-Waltsin type, Vandegraaf type, and resonant transformer type devices. The absorbed dose of the electron beam is preferably 1 to 200 kGy, more preferably 10 to 100 kGy. The accelerating voltage of the electron beam may be appropriately set in the range of 80 to 300 kV depending on the thickness of the base material, and for example, if the thickness of the base material is 100 μm, 200 kV is preferable. The oxygen concentration of the electron beam irradiation atmosphere is preferably 500 ppm or less, more preferably 300 ppm or less.

The composition of the present invention can be preferably used as an adhesive composition for optical materials, and can also be preferably used as an adhesive composition for optical films.
In this case, the laminate can be manufactured by using a thin layer adherend used as an optical member as the base material and following the same method as described above.
The optical member obtained from the composition of the present invention does not cause light reflection and has excellent adhesive strength in a high temperature and high humidity environment, so it can be used for manufacturing various optical members. Specific examples include various optical members used in display devices such as liquid crystal displays, plasma display panels, and organic EL displays, and lens sheets. More specifically, examples of display devices include backlights used in liquid crystal displays, and examples of lens sheets include prism sheets, diffusers, Fresnel lenses, and lenticular lenses.

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples below. In addition, "parts" in each of the following examples means parts by weight.

1. Examples 1 to 8, Comparative Examples 1 to 4 (Production of active energy ray-curable composition)
(A), (B), (C), (D) shown in Table 1 below and other components in the proportions shown in Table 1 are stirred and mixed in a stainless steel container to dissolve them to obtain an active energy ray-curable composition. manufactured something.
The obtained composition was used and evaluated according to the following method. The results are shown in Table 2.

2. Evaluation method
2-1. The refractive index of both the refractive index composition and the cured product at 25° C. at the D line of 589.3 nm was measured using an Abbe refractometer.
The cured product was created according to the following method.
A 7 cm square, 1 mm thick rubber sheet with a 5 cm square hole in the center was placed on a 10 cm square polyethylene terephthalate (PET) film [Therapel BX8A manufactured by Toray Industries, Inc.], and the composition was poured into the sheet, and the liquid level After laminating with the same PET film as above, the top and bottom surfaces were sandwiched and fixed between 10 cm square glass plates, and ultraviolet rays were irradiated with a 60 W/cm high pressure mercury lamp [H06-L41 manufactured by I-Graphics Co., Ltd.]. Irradiated.
The lamp height was 30 cm, and both the front and back sides were irradiated for 30 seconds, and the glass plate and PET film were removed, and the front and back sides were irradiated for 2 minutes each to obtain a cured product.

2-2. Peel Strength The composition obtained above was coated to a thickness of 10 μm on a 100 μm thick PET film (“Cosmoshine A-4360” manufactured by Toyobo Co., Ltd.) using a bar coater.
After laminating the same PET film as above, a conveyor-type ultraviolet irradiation device manufactured by Eye Graphics Co., Ltd. (160 W/cm metal halide lamp, irradiation intensity in the UV-A region 500 mW/cm ² , cumulative light amount 1, The laminate film was cured by irradiating the laminate film with two passes of ultraviolet light using a UV POWER PUCK (measured value of UV POWER PUCK manufactured by Heraeus Co. ^, Ltd.) to produce a laminate film as a test piece.

The obtained test specimen was left at 23±2°C and 50±5% RH for 24 hours, and then its peel strength was measured using a tensile tester (Instron 5564 manufactured by Instron Japan Company Limited) under the following conditions (initial peel strength).
The test conditions are as follows.
・Temperature, humidity: 23±2℃, 50±5%RH
・Test piece: 25mm x 100mm
・Test method: T-shaped peeling ・Peeling speed: 200mm/min

2-3． Environmental Test The specimen prepared above was subjected to moist heat treatment at 85° C. and 85% RH for 168 hours, and then its peel strength was measured under the same conditions as above. Evaluation was performed on the following two levels based on the rate of decrease from the peel strength immediately after curing, which is the result described above.

〇: Decrease rate of 0% or more and less than 20% ×: Decrease rate of 20% or more

In addition, the numbers in Table 1 mean the number of copies, and the abbreviations mean the following.
◆(A) component + (D) component
- OT-1001: Isobornyl acrylate of non-yellowing polyester skeleton urethane acrylate (Mw: 40,000, hereinafter referred to as "A-1") [manufactured by Osaka Organic Chemical Industry Co., Ltd.]. Hereinafter referred to as "IBXA"] 50% diluted product, "Aronix OT-1001" manufactured by Toagosei Co., Ltd.
In Table 1, A-1 corresponding to the (A) component and IBXA corresponding to the (D) component are listed separately.
◆(A) component + (B) component + (D) component
- OT-1026: 52.2% by weight diluted product of non-yellowing polyester skeleton urethane acrylate (Mw: 40,000, hereinafter referred to as "A-2"). "Aronix OT-1026" manufactured by Toagosei Co., Ltd. As a diluting solvent, nonylphenol ethylene oxide modified acrylate [Aronix M-111 manufactured by Toagosei Co., Ltd., hereinafter referred to as "M-111" was used. ], 22.4% by weight, lauryl acrylate, [manufactured by Osaka Organic Chemical Industry Co., Ltd.]. Hereinafter referred to as "LA". 〕including.
In addition, in Table 1, A-2 corresponding to the (A) component, M-111 corresponding to the (B) component [(B-3) component], and LA corresponding to the (D) component are separated. It is listed.
◆(A) Component
・UN-6202: Non-yellowing polyether skeleton urethane acrylate (Mw: 11,000), “Art Resin UN-6202” manufactured by Negami Kogyo Co., Ltd.
◆(B-1) Component
・M1142: o-phenylphenoxyethyl acrylate, “Miramer M1142” manufactured by Miwon
・POB-A: 3-phenoxybenzyl acrylate, “Light Acrylate POB-A” manufactured by Kyoeisha Chemical Co., Ltd.
◆(B-2) Component
・4-HBA: 4-hydroxybutyl acrylate, "4-HBA" manufactured by Osaka Organic Chemical Industry Co., Ltd.
◆(B-3) Component
・BzA: Benzyl acrylate, “Viscoat #160” manufactured by Osaka Organic Chemical Industry Co., Ltd.
◆(C) Component
・TPO: 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, “Omnirad TPO” manufactured by IGM Resins
◆(D) Component
・M-240: Polyethylene glycol diacrylate, “Aronix M-240” manufactured by Toagosei Co., Ltd.
◆Other ingredients
・OPP: o-phenylphenol, manufactured by Tokyo Chemical Industry Co., Ltd.

As is clear from the results of Examples 1 to 7, the composition of the present invention has a high refractive index of more than 1.54 after curing, and a high T-peel strength of more than 15 N/25 mm between PET films. It shows the peel strength.
On the other hand, in the compositions of Comparative Examples 1 and 2 in which the high refractive index component (B-1) component was less than the lower limit of 30% by weight of the present invention, the cured products had a low refractive index.
The composition of Comparative Example 3 in which the proportion of component (A) exhibiting high cohesive strength was less than the lower limit of 5% by weight of the present invention had low peel strength.
Comparing Examples 1 to 7 with Comparative Example 4, Comparative Example 4 contains a high refractive index plasticizer as described in Patent Document 2, and the proportion of the curable component is less than 70% by weight in the total composition. The composition showed a decrease in peel strength in an environmental test. Since no decrease in peel strength was observed in any of the Examples, it is thought that this is due to bleeding of the plasticizer.

The active energy ray-curable adhesive composition of the present invention has particularly excellent adhesion to plastic films, and is effective for adhering adherends such as plastic films used as various optical members. It can be suitably used for manufacturing.

Claims (10)

A composition containing the following components (A) and (B) as curable components,
Contains a curable component in a proportion of 70% by weight or more in the total amount of the composition,
Contains the following component (A) in a proportion of 5 to 30% by weight and component (B) in a proportion of 70 to 95% by weight in a total of 100% by weight of the curable components,
An active energy ray-curable adhesive composition containing the following component (C) in a proportion of 0.1 to 5 parts by weight per 100 parts by weight of the curable component.
(A) Component: Urethane (meth)acrylate having two or more (meth)acryloyl groups (B) Component: A compound having an ethylenically unsaturated group other than the (A) component, which is the following (B-1) component , (B-2) component, and (B-3) component,
In 100% by weight of the curable component, the proportion of the following component (B-1) is 30 to 75% by weight, component (B-2) is 10 to 40% by weight, and component (B-3) is 0 to 40% by weight. Component (B-1): Compound having two or more aromatic rings and one (meth)acryloyl group Component (B-2): No aromatic ring, hydroxyl group and one Component (B-3): Compound containing one aromatic ring and one ethylenically unsaturated group (C) Component: Photoradical polymerization initiator The active energy ray-curable adhesive composition according to claim 1, wherein the component (A) is a urethane di(meth)acrylate having a weight average molecular weight of 500 to 100,000. The active energy ray-curable adhesive composition according to claim 1 or 2, wherein the component (A) is a urethane di(meth)acrylate having a polyester skeleton or a polycarbonate skeleton. The active energy ray-curable adhesive composition according to any one of claims 1 to 3, wherein the component (A) is a urethane di(meth)acrylate having no aromatic skeleton. In the component (B),
The component (B-1) contains a mono(meth)acrylate having a biphenyl group or a phenoxybenzyl group,
The active energy ray-curable adhesive composition according to any one of claims 1 to 4, wherein the component (B-2) contains a hydroxyalkyl mono(meth)acrylate. The active energy ray-curable adhesive composition according to claim 5, wherein the mono(meth)acrylate having a biphenyl group in the component (B-1) is an alkylene oxide-modified phenylphenol acrylate. The active energy ray-curable adhesive composition according to any one of claims 1 to 6, wherein the cured product has a refractive index of more than 1.54. The active energy ray-curable adhesive composition according to any one of claims 1 to 7, wherein the adherend is a plastic film or sheet. Using two polyethylene terephthalate films as adherends, the cured product was irradiated with ultraviolet rays with a cumulative light intensity of 1000 mJ/cm ² using a metal halide lamp as the light source, and the cured product had a T-peel strength ( The active energy ray-curable adhesive composition according to any one of claims 1 to 8, which has a peeling speed of 200 mm/min) of 15 N/25 mm or more. The active energy ray-curable adhesive composition according to any one of claims 1 to 9 is coated and bonded to an adherend, and active energy rays are applied from either side of the adherend. A method for manufacturing a laminate to be irradiated.