WO2012173054A1 - Active-energy-ray-curable adhesive composition for plastic film or sheet - Google Patents

Abstract

[Problem] To provide an active-energy-ray-curable adhesive composition that has low viscosity, excellent curability, and excellent adherability to various plastic films and the like, particularly to hydrophilic plastic films, and that exhibits sufficient performance even in applications that require extreme durability. [Solution] The active-energy-ray-curable adhesive composition contains components (A) and (B) as curable components, and a component (C) as a polymerization initiator. The component (A) is a compound represented by formula (1) (in formula (1), R₁ is a C_1-6 alkyl group, m is an integer from 1 to 20, and R₂ is an m-valent residue of a compound selected from the group consisting of aliphatic alcohols, polyalkylene oxides, polyester polyols, compounds including a phenolic hydroxyl group, and alkylene oxide-modified products thereof). The component (B) is an ethylenically unsaturated compound. The component (C) is a photo-cationic polymerization initiator.

Description

Active energy ray-curable adhesive composition for plastic film or sheet

The present invention relates to an active energy ray-curable adhesive composition capable of adhering various plastic films or sheets by irradiation with active energy rays such as electron beams or ultraviolet rays, and the composition of the present invention. Is suitable for the adhesion of thin-layer adherends such as plastic films or sheets, and is preferably used for the production of various optical films or sheets used for liquid crystal display elements, etc. It can be used in the field.
In the present specification, acrylate and / or methacrylate is represented by (meth) acrylate, acryloyl group and / or methacryloyl group is represented by (meth) acryloyl group, and acrylic acid and / or methacrylic acid is represented by (meth) acrylic acid. .
In the following description, unless otherwise specified, a plastic film or sheet is collectively expressed as “plastic film or the like”, and a film or sheet is collectively expressed as “film or the like”.

Conventionally, in a laminating method in which a thin layer adherend such as a plastic film or between a thin layer adherend such as a plastic film and a thin layer adherend made of another material is bonded, an ethylene-vinyl acetate copolymer is used. And a solvent-type adhesive composition containing a polyurethane-based polymer is applied to the first thin-layer adherend and dried, and then the second thin-layer adherend is pressure-bonded thereto with a nip roller or the like. The dry laminating method is mainly used.
The adhesive composition used in this method generally contains a large amount of a solvent in order to make the coating amount of the composition uniform, but for this reason, a large amount of solvent vapor is volatilized during drying, resulting in toxicity, work safety and Environmental pollution is a problem. In addition, the adhesive composition is a thin layer in a post-processing step such as a heat seal for bonding the obtained laminate film and a ruled line step for engraving grooves immediately after the thin layer adherend is bonded. There is a problem that the adherends are separated from each other.
As an adhesive composition for solving these problems, a solventless adhesive composition has been studied.

As the solventless adhesive composition, a two-component adhesive composition and an adhesive composition that is cured by an active energy ray such as an ultraviolet ray or an electron beam are widely used.
As the two-component adhesive composition, a so-called polyurethane adhesive composition is mainly used in which a polymer having a hydroxyl group at the terminal is a main agent and a polyisocyanate compound having an isocyanate group at the terminal is a curing agent. However, the composition has a drawback that it takes a long time to cure, and thus there is a problem in productivity such as being unable to enter a post-processing step such as a ruled line step immediately after laminating the thin layer adherend. .
On the other hand, the active energy ray-curable adhesive composition is excellent in productivity because of its high curing rate, and has recently attracted attention.

On the other hand, liquid crystal display devices are widely used in navigation systems for automobiles, small electronic devices such as mobile phones and PDAs, screens of word processors and personal computers, and even television receivers because of their features such as thinness, light weight, and low power consumption. is doing.
In recent years, an active energy ray-curable adhesive has been used for bonding various optical films and the like used in the liquid crystal display element.

Examples of the optical film include a polarizing plate, a retardation film, a viewing angle compensation film, a brightness enhancement film, an antireflection film, an antiglare film, a lens sheet, and a diffusion sheet, and various types of plastics are used. It has been.

Among these plastics, polyvinyl alcohol and triacetyl cellulose are particularly used as polarizing plates. These plastics contain a hydroxyl group and are characterized by being very hydrophilic compared to ordinary plastics.

The active energy ray curable adhesive composition for polarizing plates includes a photo radical polymerization composition utilizing photo radical polymerization, a photo cation polymerization composition utilizing photo cation polymerization, and photo radical polymerization and photo cation polymerization. Hybrid type compositions using a combination of these are known.

As a photo radical polymerization type composition, a composition containing a radical polymerizable compound containing a polar group such as a hydroxyl group or a carboxyl group and a radical polymerizable compound not containing a polar group (Patent Document 1) is known. ing.
However, the composition has a large shrinkage during curing, and depending on the type of adherend, it has been difficult to obtain sufficient peel strength due to the generation of stress at the interface.
In order to solve this problem, a composition containing urethane (meth) acrylate having a large molecular weight has been studied (for example, Patent Document 2).
However, since the viscosity increases, the composition has a problem that thin film coating cannot be performed depending on the coating apparatus. It is also possible to reduce the shrinkage stress during curing by improving the flexibility of the adhesive composition. However, since such a means lowers the heat resistance and water resistance of the adhesive, There is a problem that defects such as peeling, foaming, and cracks occur in applications that require high performance.

As a photocationic polymerization type composition, a composition containing an epoxy resin containing no aromatic ring as a main component (Patent Document 3) or a composition containing an aliphatic epoxy and an alicyclic epoxy and / or oxetane (Patent Document 4). ) Etc. are known.
The composition has an advantage that the generation of stress at the interface can be suppressed because the shrinkage at the time of curing is relatively small compared to the radical photopolymerization type composition.
However, photocationic polymerization is generally known to cause polymerization inhibition due to moisture and basic substances. In high humidity environments, substrates with a lot of moisture, and substrates with a basic surface. It was difficult to obtain sufficient peel strength. In addition, by using a composition containing a polyfunctional epoxy resin as a main component, it is possible to reduce the effect of curability reduction due to polymerization inhibition, but such a composition increases the viscosity, Depending on the coating apparatus, there is a problem that thin film coating is not possible.

As a hybrid type composition, a composition containing a (meth) acrylate having an isocyanuric ring skeleton, an alicyclic epoxy compound, a compound containing a hydroxyl group and a photoacid generator (Patent Document 5), having two or more epoxy groups An epoxy resin in which at least one of these groups is an alicyclic epoxy group, an epoxy resin having two or more epoxy groups and no alicyclic epoxy group, a photocationic polymerization initiator and polymerization Composition containing a reactive monomer (Patent Document 6), a compound having two or more (meth) acryl groups, a compound having a hydroxyl group and one (meth) acryl group, a cationic polymerizable compound having a (meth) acryl group, light A composition including a radical polymerization initiator and a photocationic polymerization initiator (Patent Document 7) is known.

These compositions are intended to solve the problem of shrinkage during curing and polymerization inhibition due to moisture by hybridization, but according to the study of the present inventors, it has been found that there are the following problems.

The composition disclosed in Patent Document 5 contains a (meth) acrylate compound having an isocyanuric ring skeleton as an essential component, but according to the study of the present inventor, the composition having two or more (meth) acryloyl groups. When a large amount of (meth) acrylate is contained in the composition, the shrinkage at the time of curing is not so small that stress generation at the interface cannot be suppressed. For this reason, it is difficult to obtain sufficient peel strength depending on the substrate. It turned out to be.

Although the composition disclosed in Patent Document 6 includes a hybridized composition as a concept, the compositions disclosed in Examples are only compositions composed only of a photocationically polymerizable monomer. The hybridized composition is not specifically disclosed.

The composition disclosed in Patent Document 7 contains a cationic polymerizable compound having a (meth) acrylic group as an essential component at a specific ratio, but according to the study of the present inventors, the compound is often contained in the composition. If it is included, the shrinkage at the time of curing is not so small that stress generation at the interface cannot be suppressed. For this reason, it has been found that it is difficult to obtain a sufficient peel strength depending on the substrate.

JP 2008-009329 A (Claims) JP 2007-177169 A (Claims) JP 2004-245925 A (Claims) JP 2008-134384 A (Claims) JP 2008-233279 A (Claims) JP 2008-257199 A (Claims) JP 2008-260879 A (Claims)

The present invention has been made in view of the above problems, has low viscosity and excellent curability, has excellent adhesion to various plastic films, particularly hydrophilic plastic films, etc., and is sufficient for applications that require strict durability. It is an object to provide an active energy ray-curable adhesive composition for a plastic film or sheet that exhibits excellent performance.

As a result of various studies, the present inventors have determined that as a curable component,
(A) In the molecule, the following formula (1 ′)

(Wherein R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms) a compound having at least one group, and (B) an ethylenically unsaturated compound,
As the polymerization initiator, (C) an active energy ray-curable adhesive composition containing at least a photocationic polymerization initiator has an adhesive force to various plastic films, particularly hydrophilic plastic films such as polyvinyl alcohol polarizer films. It has been found that it is excellent and has low viscosity and exhibits high durability even when cured under high humidity, and the present invention has been completed.

In addition, according to the adhesive composition of this invention, the laminated body by which a base material, the hardened | cured material layer of the adhesive composition of this invention, and a plastic film or sheet | seat are laminated | stacked in this order, and a polyvinyl alcohol type polarizer A polarizing plate or the like obtained by laminating a film or sheet, a cured product layer of the adhesive composition of the present invention, and a plastic film or sheet in this order is obtained.
Hereinafter, the present invention will be described in detail.

The composition of the present invention uses a compound represented by the above formula (1) and an ethylenically unsaturated compound as a curable component and can be cured with at least a photocationic polymerization initiator. Excellent workability, and can exhibit high durability even when cured under high humidity, such as various plastic films, especially hydrophilic plastic films such as polyvinyl alcohol polarizer films, etc. It is effective for adhesion of the thin layer adherend, and can be suitably used for the production of an optical film particularly used for a liquid crystal display device or the like.

The present invention comprises at least a curable component and a polymerization initiator, the curable component comprises at least the following components (A) and (B), and the polymerization initiator comprises at least the following component (C). The present invention relates to an active energy ray-curable adhesive composition suitable for a plastic film or sheet.
(A): The following formula (1)

(In the formula (1), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, m is an integer of 1 to 20, and R ₂ is a linear chain having 1 to 20 carbon atoms. Or branched aliphatic alcohols and their alkylene oxide modified products, linear or branched polyalkylene oxides, polyester polyols, aromatic alcohols and their alkylene oxide modified products, and compounds having phenolic hydroxyl groups and their alkylene oxide modified products M-valent residue of a compound selected from the group consisting of compounds may contain —OCH ₂ C (OH) (R ₁ ) CH ₂ O— units.

A compound represented by the following [hereinafter referred to as “component (A)”].
(B): ethylenically unsaturated compound [hereinafter referred to as “component (B)”].
(C): Photocationic polymerization initiator [hereinafter referred to as “component (C)”].
Moreover, the adhesive composition of the present invention may contain (D) a radical photopolymerization initiator (hereinafter referred to as “component (D)”) as desired.
Hereinafter, each component will be described.

1. Component (A) The component (A) is a compound having at least one glycidyl group having an alkyl substituent at the alpha position of the oxirane ring via an ether bond as represented by the formula (1). is there.

R _{1 in the} formula (1) is an alkyl group having 1 to 6 carbon atoms, and this alkyl group may be linear or branched, and considering the convenience of synthesis, a methyl group or an ethyl group is A methyl group is particularly preferable.
m is an integer of 1 to 20, preferably 1 to 5, and more preferably 1 to 3.

R ₂ represents a linear or branched aliphatic alcohol having 1 to 20 carbon atoms, a linear or branched poly (alkyleneoxy), a polyester polyol, an aromatic alcohol and an alkylene oxide modified product thereof, and a phenolic hydroxyl group. And a m-valent residue of a compound selected from the group consisting of modified alkylene oxides thereof, and may contain —OCH ₂ C (OH) (R ₁ ) CH ₂ O— units.
When the compound of formula (1) is produced, the epoxy groups of the obtained epoxy compound may react to form a multimer, but when the multimer is formed, R ₂ is —OCH ₂ C ( OH) (R ₁ ) CH ₂ O— units.
Among these, R ₂ is preferably an m-valent residue of a compound selected from the group consisting of a compound having a phenolic hydroxyl group and a modified alkylene oxide thereof. In this case, —OCH ₂ C (OH) (R ₁ ) CH ₂ O— units may be included.

Component (A) is, for example, an alkyl epichlorohydrin represented by the following formula (2) (hereinafter referred to as compound (2)) having one hydroxyl group such as an alcohol or phenol represented by the following formula (3) in the molecule. It can be easily produced by reacting the above compound with a known method (for example, see JP-A-08-283379).

(In the formula (2), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms)

(In the formula (3), m is an integer of 1 to 20, and R ₂ is a linear or branched aliphatic alcohol having 1 to 20 carbon atoms, linear or branched poly (alkyleneoxy). , A polyester polyol, an aromatic alcohol and an alkylene oxide modified product thereof, and a m-valent residue of a compound selected from the group consisting of a compound having a phenolic hydroxyl group and an alkylene oxide modified product thereof.

The reaction residue of the compound represented by formula (3) (hereinafter referred to as compound (3)) is R _{2 in} formula (1).
Specific examples of the compound (3) are given below.

○ Linear or branched aliphatic alcohols having 1 to 20 carbon atoms Linear or branched aliphatic alcohols having 1 to 20 carbon atoms include methanol, ethanol, propanol, isopropanol, butanol, hexanol, 2- Aliphatic monohydric alcohols which may have 1 to 20 carbon atoms such as ethylhexanol; glycols such as ethylene glycol, propylene glycol and neopentyl glycol; 1,3-propanediol, 1,4-butanediol, Aliphatic polyhydric alcohols such as 1,6-hexanediol, aliphatic polyhydric alcohols such as trimethylolpropane, trimethylolethane, glycerin, diglycerin, erythritol, pentaerythritol, sorbitol; alicyclic groups such as norbornane dimethanol Including aliphatic polyhydric alcohols; These alkylene oxide modified products are exemplified.

○ Linear or branched polyalkylene oxide Examples of the linear or branched polyalkylene oxide include linear or branched polyalkylene oxides such as polyethylene glycol, polypropylene glycol, polybutylene glycol, and polytetramethylene glycol. It is done.

○ Polyester polyol Examples of the polyester polyol include those obtained by reacting a polyhydric alcohol and a polycarboxylic acid.

Aromatic alcohol Examples of the aromatic alcohol include xylylene glycol and the like, and modified alkylene oxides thereof.

O Compound having phenolic hydroxyl group Examples of the compound having a phenolic hydroxyl group include phenol, bisphenol, biphenol, and a phenol resin. Among these, compounds selected from the group consisting of phenol, bisphenol, and phenol resin are preferable.
Examples of phenol include monovalent compounds such as phenol, divalent or higher compounds such as catechols and pyrogallols, phenol derivatives substituted with hydrogen atoms of aromatic rings such as cumylphenol, and aromatic rings. Examples thereof include phenol derivatives in which a hydrogen atom is substituted with a linear or branched alkyl group having 1 to 6 carbon atoms, and modified alkylene oxides thereof.
Examples of the bisphenol include bisphenol derivatives such as bisphenol A and bisphenol F, and alkylene oxide modified products thereof.
Examples of the biphenol include biphenol, biphenol having 1 to 6 chain or branched alkyl groups, and modified alkylene oxides thereof.
Examples of the phenol resin include a phenol novolac resin, a cresol novolac resin, and polyvinylphenol.

In the compounds exemplified above as an alkylene oxide modified product, examples of the alkylene oxide modified product include an ethylene oxide modified product and a propylene oxide modified product.

Preferred examples of the compound (3) include alkyl alcohols having 1 to 8 carbon atoms which may have branches, ethylene glycol modified products of alkyl alcohols having 1 to 8 carbon atoms which may have branches, ethylene Glycol, propylene glycol, polyethylene glycol, polypropylene glycol, phenol, modified ethylene oxide of catechol, catechol, modified ethylene oxide of catechol, modified ethylene oxide of t-butylcatechol, t-butylcatechol, pyrogallol, ethylene oxide of pyrogallol Modified products, biphenylphenol, ethylene glycol modified products of biphenylphenol, bisphenol A, ethylene glycol modified products of bisphenol A, bisphenol F, ethylene oxide of bisphenol F Id modified products include phenol novolac resin and cresol novolac resin.

M in the formula (3) is an integer of 1 to 20, preferably 1 to 5, and more preferably 1 to 3.

As a method for producing the component (A) from the compound (2) and the compound (3), a known production method for obtaining an epoxy compound can be used.
For example, when the component (A) is produced from the compound (2) and a polyhydric phenol as the compound (3), it can be obtained by reacting with an alkali compound.
As the alkali compound, alkali metal or alkaline earth metal hydroxide, carbonate, bicarbonate and the like can be used. Specifically, sodium hydroxide, calcium hydroxide, potassium hydroxide, sodium carbonate, Sodium hydrogencarbonate etc. are mentioned, These mixtures can also be used. Examples of the reaction temperature at this time include 30 to 120 ° C.
Even when a monohydric alcohol or a polyhydric alcohol is used as the compound (3), it can be obtained in the same manner as described above.
When obtaining the component (A) represented by the formula (1) from the compound (2) and the compound (3) in which m is 2 or more, depending on the production method, a part thereof is polymerized to have a high molecular weight. In which the cationic polymerization promoting group represented by the above formula (1 ′) is bonded to both ends thereof. Such a polymer can also be used as the component (A) of the present invention. Examples of such polymers that can be obtained include those wherein m is 2 or more in formula (3), and the actual compounds include resorcinol, bisphenol A, bisphenol F, phenol novolac resin, cresol novolac resin and norbornane. Methanol etc. can be illustrated.

The component (A) is a compound represented by the above formula (1), wherein m is 1 or 2, and R ₂ is a m-valent residue of a compound having a phenolic hydroxyl group and a modified alkylene oxide thereof. , —OCH ₂ C (OH) (R ₁ ) CH ₂ O— units are preferable, and preferred examples of the compound are shown in the following formulas (5) to (9).

(In Formula (5), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, and n is 0 or a positive number.)
In the formula (5), the compound of the formula (2) may be bonded to any of the o-position, m-position, and p-position, preferably the o-position or m-position. R _{1 in the} formula (5) is a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group. N in the formula (5) is 0 or a positive number, preferably 0 to 10, more preferably 0 to 5, and particularly preferably 0 to 1.

(In Formula (6), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, and n is 0 or a positive number.)
In the formula (6), the compound of the formula (2) may be bonded to any of the o-position, m-position, p-position, o'-position, m'-position or p'-position, preferably the o-position, p-position. Is the position, o′-position, or p′-position (where the o-position, m-position, and p-position are the compounds of the formula (2) bonded to the benzene ring at one end of the formula (6). And the o′-position, m′-position and p′-position are bound to the terminal benzene ring on the opposite side). R _{1 in the} formula (6) is a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group.
N in the formula (6) can be adjusted by, for example, the amount of the compound of the formula (2) used relative to bisphenol F. N in the formula (6) is 0 or a positive number, preferably 0 to 10, more preferably 0 to 5, and particularly preferably 0 to 1. And the bond position between bisphenol F when n of Formula (6) is a positive number may be any, and p, p 'position, o, p' position, o ', p position or o, o' position is preferable. .

(In Formula (7), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, and R ₃ is a linear or branched alkyl group having 1 to 6 carbon atoms)
In Formula (7), R ₃ may be bonded to any of the o-position, m-position, and p-position, and is preferably the o-position or p-position. R _{1 in the} formula (7) is a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group. R _{3 in the} formula (7) is a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a butyl group, a t-butyl group or a hexyl group, and more preferably a t-butyl group.

(In Formula (8), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms)
R _{1 in the} formula (8) is a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group.

(In Formula (9), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, and n is 0 or a positive number.)
In the formula (9), the formula (1) may be bonded to any of the o-position, m-position, p-position, o′-position, m′-position or p′-position, preferably the o-position, p-position, o′-position or p′-position (note that the o-position, m-position and p-position indicate that the compound of the formula (2) is bonded to the benzene ring at one end of the formula (9). And the o′-position, m′-position and p′-position are bound to the terminal benzene ring on the opposite side). R _{1 in the} formula (9) is a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group.
N in the formula (9) can be adjusted by, for example, the amount of the compound of the formula (2) used relative to bisphenol A. N in the formula (9) is 0 or a positive number, preferably 0 to 10, more preferably 0 to 5, and particularly preferably 0 to 1. The bonding position between bisphenol A when n in Formula (9) is a positive number may be any, and p, p ′ position, o, p ′ position, o ′, p position or o, o ′ position is preferable. .

As the component (A), among the compounds of the above formulas (5) to (9), the compounds of the formulas (5), (6) and (8) are preferable, and when used for adhesion of hydrophilic plastics or sheets. Is preferably a compound of the formula (6) from the viewpoint of excellent solubility, adhesive strength, heat resistance and the like.

As the component (A), only one kind of the aforementioned compounds can be used, or two or more kinds can be used in combination.

The blending ratio of the component (A) is 20 to 70% by weight, preferably 30 to 60% by weight in 100% by weight of the total amount of the curable component. By making the ratio of the component (A) 20% by weight or more, the cured product has excellent heat resistance and water resistance, and by making it 70% by weight or less, the composition has low viscosity and excellent coating properties. It becomes a thing and it becomes the thing excellent in the adhesive force of hardened | cured material.

2. Component (B) The component (B) is an ethylenically unsaturated compound, and various compounds can be used as long as the compound has an ethylenically unsaturated group.
Examples of ethylenically unsaturated groups include (meth) acryloyl groups, vinyl groups, and vinyl ether groups.
The proportion of component (B) is preferably 30 to 80% by weight, more preferably 40 to 70% by weight, based on 100% by weight of the total amount of the curable component.
By making the ratio of the component (B) 30% by weight or more, it is possible to improve curability and reduce the viscosity, and by making it 80% by weight or less, it is possible to prevent a decrease in the adhesive strength and water resistance of the composition. be able to.

As the component (B), (b1) an ethylenically unsaturated compound having a hydroxyl group (hereinafter referred to as “component (b1)”), a compound having two or more ethylenically unsaturated groups in the molecule [hereinafter referred to as (b2 And a compound other than the components (b1) and (b2) (hereinafter referred to as other monofunctional unsaturated compounds) having one ethylenically unsaturated group in the molecule.

The component (b1) is an ethylenically unsaturated compound having a hydroxyl group.
The component (b1) is preferably a (meth) acrylate having one hydroxyl group and one ethylenically unsaturated group in the molecule.
Specific examples of the (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, cyclohexane Dimethanol monoacrylate, (meth) acrylic acid adduct of cyclohexene oxide, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polytetramethylene glycol mono (meth) acrylate, polyethylene glycol-polypropylene glycol mono (meth) ) Acrylate, polyethylene glycol-polytetramethylene glycol mono (meth) acrylate, polypropylene glycol-polytetramethylene glycol Mono (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy-3-butoxypropyl (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, 2- ( And (meth) acryloyloxyethyl-2-hydroxypropyl phthalate.

Among the components (b1), a compound having a molecular weight of less than 300 is preferable in order to make the composition have a low viscosity and excellent adhesiveness. Examples of the compound satisfying the molecular weight include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and cyclohexanedimethanol monoacrylate. And (meth) acrylic acid adduct of cyclohexene oxide, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and the like. Among these, 4-hydroxybutyl (meth) acrylate is more preferable from the viewpoint of water resistance.

The proportion of the component (b1) is preferably 10 to 50% by weight, more preferably 20 to 40% by weight, based on 100% by weight of the total amount of the curable component.
By making the proportion of component (b1) 10% by weight or more, it becomes possible to improve curability and reduce the viscosity, and by making it 50% by weight or less, it is possible to prevent a decrease in the adhesive strength and water resistance of the composition. be able to.

In the component (A) of the present invention, a phenomenon called so-called dark reaction, in which the reaction proceeds and cures even after the active energy ray irradiation is completed, may cause problems depending on the application. For example, in the case of manufacturing a laminate using adhesion of a film-like substrate, if the film laminate is wound after irradiation with active energy rays, the dark reaction proceeds and the wound shape remains as it is. There is a problem that marks such as wave undulations and dents are easily attached.
In order to prevent such a problem, it is very effective to include the component (b2) in the component (B) so that the elastic modulus of the adhesive layer is increased immediately after irradiation with the active energy ray. In addition, the heat resistance is improved by increasing the crosslinking density.

As the component (b2), a compound having two or more (meth) acryloyl groups (hereinafter referred to as “polyfunctional (meth) acrylate”) is preferable.
Specific examples of the polyfunctional (meth) acrylate include 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-nonanediol diacrylate, 2-methyl-1,8-octanediol di (meth) acrylate, 2-hydroxy-1, 3-di (meth) acryloyloxypropane, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, glycerin di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate , Pentaerythritol tetra (meth) Acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ditrimethylolpropane tetra (meth) polyol poly (meth) acrylates such as acrylate;
Di (meth) acrylate of neopentyl glycol alkylene oxide adduct, di (meth) acrylate of 1,6-hexanediol alkylene oxide adduct, tri (meth) acrylate of alkylene oxide adduct of glycerin, trimethylolpropane alkylene oxide addition Poly (meth) acrylates of alkylene oxide adducts of polyols such as tri (meth) acrylates of products, tri (meth) acrylates of pentaerythritol alkylene oxide adducts;
Glycol modified polyol poly (meth) acrylate such as neopentyl glycol modified trimethylolpropane di (meth) acrylate;
Caprolactone-modified polyol poly (meth) acrylates such as caprolactone-modified dipentaerythritol hexa (meth) acrylate;
Alkylene glycol di (meth) acrylates such as ethylene glycol di (meth) acrylate and propylene glycol di (meth) acrylate and tetramethylene glycol di (meth) acrylate;
Diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyalkylene glycol di (meth) acrylate;
Di (meth) acrylates of alicyclic diols such as tricyclodecane dimethylol di (meth) acrylate and dicyclopentanyl di (meth) acrylate;
Di (meth) acrylate of bisphenol A alkylene oxide adduct, di (meth) acrylate of bisphenol F alkylene oxide adduct and di (meth) acrylate of bisphenol S alkylene oxide adduct (Meth) acrylate;
Di (meth) acrylates of hydrogenated bisphenol compounds such as di (meth) acrylate of alkylene oxide adducts of hydrogenated bisphenol A and di (meth) acrylates of alkylene oxide adducts of hydrogenated bisphenol F;
Poly (meth) acrylates of isocyanuric acid such as di (meth) acrylate of isocyanuric acid alkylene oxide adduct, tri (meth) acrylate of isocyanuric acid alkylene oxide adduct, tri (meth) acrylate of isocyanuric acid caprolactone adduct;
Di (meth) acrylates of ester diols such as neopentyl glycol hydroxypivalic acid di (meth) acrylate and hydroxypivalic acid neopentyl glycol di (meth) acrylate;
Di (meth) acrylates of caprolactone-modified ester diols such as caprolactone-modified neopentyl glycol hydroxypivalic acid di (meth) acrylate;
Fatty acid-modified dipentaerythritol penta (meth) acrylate and fatty acid-modified dipentaerythritol tetra (meth) acrylate obtained by reacting a polyol with (meth) acrylic acid and a fatty acid having 2 to 4 carbon atoms;
Triacrylformal; and aromatic polyfunctional (meth) acrylates such as trimethylolpropane (meth) acrylic acid benzoate ester, Ogsol EA-0200, 0500, 1000 (fluorene acrylate, manufactured by Osaka Gas Chemical).
Examples of the alkylene oxide adduct include an ethylene oxide adduct and a propylene oxide adduct.

In addition, examples of the oligomer that can be used as the component (b2) include polyester (meth) acrylate, epoxy (meth) acrylate, and polyether (meth) acrylate. These oligomers are compounds having two (meth) acryloyl groups, but are simply referred to as (meth) acrylates unless otherwise specified.

Examples of the polyester (meth) acrylate include a dehydration condensate of polyester polyol and (meth) acrylic acid.

Here, examples of the polyester polyol include a reaction product of a carboxylic acid with a polyol or an anhydride thereof.
Polyols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, butylene glycol, polybutylene glycol, tetramethylene glycol, hexamethylene glycol, neo Low molecular weight polyols such as pentyl glycol, cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, trimethylolpropane, glycerin, pentaerythritol and dipentaerythritol, and their alkylene oxide adducts Etc.
As the carboxylic acid or its anhydride, dibasic acid such as orthophthalic acid, isophthalic acid, terephthalic acid, adipic acid, succinic acid, fumaric acid, maleic acid, hexahydrophthalic acid, tetrahydrophthalic acid and trimellitic acid or anhydrous Thing etc. are mentioned.
Examples of polyester poly (meth) acrylates other than these include compounds described on pages 74 to 76 of the above-mentioned document “UV / EB Curing Material”.

Epoxy (meth) acrylate is a compound obtained by addition reaction of (meth) acrylic acid to an epoxy resin, and examples thereof include compounds as described on pages 74 to 75 of the above-mentioned document “UV / EB Curing Material”. .

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 an alkylene oxide adduct thereof; phenol novolac type epoxy resin and cresol novolac type Examples thereof include novolak-type epoxy resins such as epoxy resins; glycidyl phthalimide; o-phthalic acid diglycidyl ester and the like.
In addition to these, the document “Epoxy Resin-Recent Advances” (Shojodo, published in 1990), Chapter 2 and the document “Polymer Processing”, Volume 9, Volume 22 Special Issue Epoxy Resin [Polymer Publications, Compounds published on pages 4 to 6 and pages 9 to 16 of 1973.

Specific examples of the aliphatic epoxy resin 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 ethers of polyalkylene glycols; diglycidyl ethers of neopentyl glycol, dibromoneopentyl glycol and its alkylene oxide adducts; di- or triglycidyl ethers of trimethylolethane, trimethylolpropane, glycerin and its alkylene oxide adducts; Of polyhydric alcohols such as di-, tri- or tetraglycidyl ethers of pentaerythritol and its alkylene oxide adducts Ether; hydrogenated bisphenol A and di- or polyglycidyl ethers of alkylene oxide adducts; tetrahydrophthalic acid diglycidyl ether; hydroquinone diglycidyl ether, and the like.
In addition to these, the compounds described on pages 3 to 6 of the above-mentioned document “Polymer Processing”, separate volume epoxy resin, can be mentioned.

In addition to these aromatic epoxy resins and aliphatic epoxy resins, epoxy compounds having a triazine nucleus in the skeleton, such as TEPIC [Nissan Chemical Co., Ltd.], Denacol EX-310 [Nagase Kasei Co., Ltd.], etc., can be mentioned. Examples thereof include compounds described on pages 289 to 296 of the above-mentioned document “Polymer Processing”, separate volume epoxy resin.
In the above, the alkylene oxide of the alkylene oxide adduct is preferably ethylene oxide or propylene oxide.

Examples of the polyether (meth) acrylate oligomer include polyalkylene glycol (meth) diacrylate, and examples thereof include polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, and polytetramethylene glycol di (meth) acrylate. .

Examples of compounds other than the component (b2) (meth) acrylate include compounds having two or more allyl groups, such as diallyl phthalate, triallyl isocyanurate, and triallyl cyanurate.
As the polymer that can be used as the component (b2), a (meth) acrylic polymer having a (meth) acryloyloxy group, a (meth) acrylic polymer having a functional group, and a (meth) acryloyl group introduced into the side chain And compounds described on pages 78 to 79 of the above-mentioned document “UV / EB Curing Material”.

In terms of preventing problems caused by dark reactions and improving heat resistance, the component (b2) includes polyalkylene glycol di (meth) acrylate, tricyclodecanedimethylol di (meth) acrylate, and a modified alkylene oxide of bisphenol A. Di (meth) acrylate, bisphenol F alkylene oxide modified di (meth) acrylate, and isocyanuric acid alkylene oxide modified triacrylate are preferred. Polyalkylene glycol di (meth) acrylate and isocyanuric acid-modified alkylene oxide triacrylate are particularly preferred because they can maintain adhesive strength with hydrophilic plastics.
The blending ratio of the component (b2) is preferably 1 to 50% by weight, more preferably 1 to 30% by weight in 100% by weight of the total amount of the curable component.
By making the proportion of the component (b2) 1% by weight or more, it becomes possible to prevent problems due to dark reaction and improve curability, and by making it 50% by weight or less, the curing shrinkage of the composition is suppressed, It can be excellent in adhesive strength.

Other monofunctional unsaturated compounds include vinyl compounds and allyl compounds, (meth) acrylamide compounds, compounds having an aromatic or alicyclic skeleton containing one ethylenically unsaturated group in the molecule, aliphatic Examples include (meth) acrylate, carboxylic acid group-containing (meth) acrylate, and phosphoric acid group-containing (meth) acrylate.

In order to make the composition have low viscosity and excellent heat resistance and adhesive strength, a compound having an aromatic ring skeleton or alicyclic skeleton having one ethylenically unsaturated group is preferable. Specific examples include alicyclic (meth) acrylates, aromatic (meth) acrylates, and imide (meth) acrylates.

Cycloaliphatic (meth) acrylates include isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, tetrahydro Examples include furfuryl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentenyl (meth) acrylate, adamantyl (meth) acrylate, tricyclodecane (meth) acrylate, and dicyclopentenyloxyethyl (meth) acrylate.

As aromatic (meth) acrylate, phenyl (meth) acrylate, phenol derivative (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenol alkylene oxide modified (meth) acrylate, cresol (Meth) acrylate of modified alkylene oxide, (meth) acrylate of modified alkylene oxide of p-cumylphenol, (meth) acrylate of modified alkylene oxide of nonylphenol, (meta) of modified alkylene oxide of o-phenylphenol ) Acrylate, (meth) acrylate of p-phenylphenol modified with alkylene oxide, (meth) acrylate of tribromophenol with modified alkylene oxide, neope Chill glycol (meth) acrylic acid benzoic acid ester.

Examples of the imide (meth) acrylate include N- (meth) acryloyloxyethylhexahydrophthalimide, 2- (1,2-cyclohex-1-enecarboximido) ethyl (meth) acrylate, and funkryl FA-502A (Hitachi Chemical Industries). Manufactured) and the like.

Among them, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxy are used because of their high heat resistance and adhesive strength. Ethyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, (meth) acrylate of a phenol alkylene oxide modified product, N- (meth) acryloyloxyethyl hexahydrophthalimide, 2- (1,2- Cyclohex-1-enedicarboximido) ethyl (meth) acrylate and the like are preferable.

Examples of vinyl compounds include monofunctional vinyl compounds such as styrene, vinyl toluene, N-vinyl pyrrolidone, N-vinyl caprolactam, vinyl imidazole and vinyl pyridine, and vinyl compounds such as divinylbenzene.

Examples of allyl compounds include monofunctional allyl compounds such as allyl alcohol.

Examples of the (meth) acrylamide compound include diacetone (meth) acrylamide, isobutoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, t-octyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, (meth) acryloylmorpholine, acrylamide-2-methylpropanesulfonic acid, N-isopropyl (meth) acrylamide and the like can be mentioned.

Specific examples of the aliphatic (meth) acrylate include 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, laur (Meth) acrylate, alkyl (meth) acrylate having 12 to 13 carbon atoms, cetyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, isomyristyl (meth) acrylate, methoxyethyl (meth) acrylate , 3-methoxybutyl (meth) acrylate, ethyl carbitol (meth) acrylate, 2-ethylhexyl carbitol (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate , Ethoxydiethylene glycol (meth) acrylate, ethoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxypolyethyleneglycol Le (meth) acrylate, methoxy polypropylene glycol (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 7-amino-3,7-dimethyl-octyl (meth) acrylate.

Examples of the carboxylic acid group-containing (meth) acrylate include (meth) acrylic acid, (meth) acrylic acid dimer, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethylphthalic acid, 2- Examples thereof include carboxylic acid-containing (meth) acrylates such as (meth) acryloyloxyethyl hexahydrophthalic acid and ω-carboxypolycaprolactone (meth) acrylate.

Examples of the phosphoric acid group-containing (meth) acrylate include 2- (meth) acryloyloxyethyl acid phosphate.

In addition to these, as component (B) that can be used as other monofunctional unsaturated compounds, it is described on pages 53 to 56 of the document "Latest UV Curing Technology" [Printed Information Association, 1991]. Compounds.
The ratio of the other monofunctional unsaturated compound is preferably 0 to 40% by weight, more preferably 0 to 30% by weight in 100% by weight of the total amount of the curable component. By making this ratio 40% by weight or less, the heat resistance of the cured product can be increased.

3. (C) Component (C) component is a photocationic polymerization initiator.
The component (C) is a compound that generates a cation or a Lewis acid by irradiation with active energy rays and starts polymerization of the component (A) that is a photocationically polymerizable compound.
Specific examples of the component (C) include sulfonium salts, iodonium salts, and diazonium salts.

Examples of sulfonium salts include, for example:
Triphenylsulfonium hexafluorophosphate,
Triphenylsulfonium hexafluoroantimonate,
Triphenylsulfonium tetrakis (pentafluorophenyl) borate,
Diphenyl-4- (phenylthio) phenylsulfonium hexafluorophosphate,
Diphenyl-4- (phenylthio) phenylsulfonium hexafluoroantimonate,
4,4′-bis [diphenylsulfonio] diphenyl sulfide bishexafluorophosphate,
4,4′-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenyl sulfide bishexafluoroantimonate,
4,4′-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenyl sulfide bishexafluorophosphate,
7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone hexafluoroantimonate,
7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone tetrakis (pentafluorophenyl) borate,
4-phenylcarbonyl-4′-diphenylsulfonio-diphenyl sulfide hexafluorophosphate,
4- (p-tert-butylphenylcarbonyl) -4′-diphenylsulfonio-diphenyl sulfide hexafluoroantimonate,
Examples include triarylsulfonium salts such as 4- (p-tert-butylphenylcarbonyl) -4′-di (p-toluyl) sulfonio-diphenyl sulfide tetrakis (pentafluorophenyl) borate.

Examples of iodonium salts include, for example:
Diphenyliodonium tetrakis (pentafluorophenyl) borate,
Diphenyliodonium hexafluorophosphate,
Diphenyliodonium hexafluoroantimonate,
Di (4-t-butylphenyl) iodonium hexafluorophosphate,
Di (4-t-butylphenyl) iodonium hexafluoroantimonate,
Trilcumyl iodonium tetrakis (pentafluorophenyl) borate,
Iodonium (4-methylphenyl) [4- (2-methylpropyl) phenyl] -hexafluorophosphate,
Di (4-nonylphenyl) iodonium hexafluorophosphate,
Examples thereof include diaryl iodonium salts such as di (4-alkylphenyl) iodonium hexafluorophosphate.

Examples of diazonium salts include benzenediazonium hexafluoroantimonate,
Examples thereof include benzenediazonium hexafluorophosphate.

As a commercial item of (C) component,
Adekaoptomer SP-100, 150, 152, 170, 172 (made by ADEKA),
Photoinitiator 2074 (made by Rhodia),
Kayrad PCI-220, 620 (Nippon Kayaku Co., Ltd.), Irgacure 250 (Ciba Japan), CPI-100P, 101A, 200K, 210S (San Apro), WPI-113, 116 (Wako Pure Chemical Industries) ), BBI-102, BBI-103, TPS-102, TPS-103, DTS-102, DTS-103 (manufactured by Midori Chemical) and the like.
Among these, triarylsulfonium salts and diaryliodonium salts are preferred because of their excellent active energy ray curability, cured films having excellent water resistance and no coloring, and diaryliodonium salts are particularly preferred because of their excellent curability. preferable.
Among the above-mentioned triarylsulfonium salts, triphenylsulfonium hexafluorophosphate and diphenyl-4- (phenylthio) phenylsulfonium hexafluorophosphate are preferable. Among the diaryl iodonium salts, among those described above, tricumyl iodonium tetrakis (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, iodonium (4-methylphenyl) [4- (2-methylpropyl) phenyl] -hexafluoro Preferred are phosphate, di (4-t-butylphenyl) iodonium hexafluorophosphate, and WPI-113 (manufactured by Wako Pure Chemical Industries).

As the component (C), the aforementioned compounds may be used alone or in combination of two or more.
The blending ratio of the component (C) is 0.1 to 20% by weight, preferably 1 to 10% by weight, based on 100 parts by weight of the total amount of the curable component. By making the proportion of the component (C) 0.1% by weight or more, the active energy ray curability of the composition can be made sufficient and the adhesiveness can be made excellent, while it is made 20% by weight or less. As a result, the internal curability of the adhesive layer can be improved and the adhesiveness can be improved.

Moreover, in this invention, in order to improve photocationic sclerosis | hardenability, a sensitizer can also be used and these are also included as (C) component.
Examples of the sensitizer include anthracene compounds, 4-methoxy-1-naphthol, fluorene, pyrene, stilbene and the like.
Examples of the anthracene compound include anthracene, 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dipropoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 2-ethyl-9,10- Diethoxyanthracene, 2-ethyl-9,10-dipropoxyanthracene, 4′-nitrobenzyl-9,10-dimethoxyanthracene-2-sulfonate, 4′-nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate And 4'-nitrobenzyl-9,10-dipropoxyanthracene-2-sulfonate.
Among these, 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, and 9,10-dipropoxyanthracene are preferable from the viewpoints of solubility and sensitization efficiency.
Commercially available products of these sensitizers include Anthracure UVS-1331, 1221, 1101, and ET-2111 (manufactured by Kawasaki Chemical Industries).

The blending ratio of the sensitizer is preferably 0.1 to 20% by weight, more preferably 1 to 10% by weight with respect to 100 parts by weight of the total amount of the curable component.
When the ultraviolet light of the plastic as the adherend is large and a sulfonium salt is used as the component (C), an anthracene compound is preferably used as a sensitizer.

4). (D) Component (D) A component is a radical photopolymerization initiator.
Component (D) is a compound that generates radicals by irradiation with active energy rays and initiates polymerization of component (B), which is a compound having an ethylenically unsaturated group. Some types of component (D) function as a sensitizer that promotes photolysis of component (C).

Specific examples of the component (D) 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, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 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-morpholinopropane-1-o 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl -Aromatic ketone compounds such as phenyl) -butan-1-one, Adekaoptomer N-1414 (Asahi Denka), 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 Benzophenone series 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) phenylphosphinate and bis (2, Acylphosphine 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-thioxanthone-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] Oxime esters such as 1- (O-acetyloxime), 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-dimethoxy 2,4,5-triarylimidazole dimers such as phenyl) -4,5-diphenylimidazole dimer; and acridines such as 9-phenylacridine and 1,7-bis (9,9'-acridinyl) heptane Derivatives and the like.

Of these, thioxanthone compounds are preferred because of the high sensitizing effect of component (C). Among the thioxanthone compounds, 2,4-diethylthioxanthone and isopropylthioxanthone are more preferable from the viewpoint of excellent active energy ray curability and small coloration of the cured film.

As the component (D), the above-described compounds may be used alone, or two or more kinds may be used in combination.

The proportion of component (D) is 0.1 to 20% by weight, preferably 1 to 10% by weight, based on 100 parts by weight of the total amount of the curable component. By making the proportion of the component (D) 0.1 weight or more, the active energy ray curability of the composition can be made sufficient and the adhesiveness can be made excellent, while it is made 20 weight% or less. Thus, the internal curability of the adhesive layer can be made good and the adhesiveness can be made excellent.

5. Other components In the present invention, in addition to the components (A), (B), (C), and (D), other components can be blended as necessary.

Preferable components that can be used in the present invention include compounds other than the component (A) having at least one cationic polymerizable group in the molecule. Applicable compounds include epoxy compounds in which R ₁ in formula (1) is hydrogen (hereinafter referred to as unsubstituted epoxy compounds), alicyclic epoxies, oxetane compounds, and vinyl ether compounds.

An unsubstituted epoxy compound is divided into an aromatic type and an aliphatic type.
Examples of aromatic systems include diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, diglycidyl ether of bisphenol S, diglycidyl ether of brominated bisphenol A, diglycidyl ether of brominated bisphenol F, brominated bisphenol Diglycidyl ether of S, diglycidyl ether of rubber-modified bisphenol A, bisphenol type epoxy resin such as di- or polyglycidyl ether of bisphenolfluorene or its alkylene oxide adduct; phenol novolac type epoxy resin, cresol novolak type epoxy resin, bromination Phenol novolac epoxy resin, brominated cresol novolac epoxy resin, dicyclopentadiene-phenol novolac epoxy resin, etc. Borac type epoxy resin, naphthalene type epoxy resin, alkyldiphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, hydroquinone diglycidyl ether, resorcin diglycidyl ether, terephthalic acid diglycidyl ether, phthalic acid diglycidyl ether, styrene -Epoxidized butadiene copolymer, epoxidized styrene-isoprene copolymer, addition reaction product of terminal carboxylic acid polybutadiene and bisphenol A type epoxy resin, N, N, N ', N'-tetraglycidyl-m-xylene Examples include diamines.
In addition to these, the document “Epoxy Resin-Recent Advances” (Shojodo, published in 1990), Chapter 2 and the document “Polymer Processing”, Vol. 9, Volume 22 Epoxy Resin (Polymer Publishing) Compounds published on pages 4 to 6, 9 to 16, and 29 to 55 of the Society, published in 1978.
Here, the epoxy resin means a compound or polymer having an average of two or more unsubstituted epoxy groups in the molecule and cured by reaction. In accordance with common practice in this field, in the present specification, a monomer having two or more curable unsubstituted epoxy groups in its molecule may be referred to as an epoxy resin.

Aromatic unsubstituted epoxy compounds other than these include Epicoat 5050, 5051, 1031S, 1032H60, 604, 630, 871, 872, 191P, YX310, 545, YL6810, YX8800, YL980 [above, Japan Epoxy Resin ( Etc.].

Specific examples of the aliphatic unsubstituted epoxy compound include diglycidyl ethers of alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol; diglycidyl of polyethylene glycol and polypropylene glycol Diglycidyl ether of polyalkylene glycol such as ether; diglycidyl ether of neopentyl glycol, dibromoneopentyl glycol and its alkylene oxide adduct; di- or triglycidyl of trimethylolethane, trimethylolpropane, glycerin and its alkylene oxide adduct Polyethers of ethers and 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 alkylene oxide adducts; glycidyl ether tetrahydrophthalic acid diglycidyl ether; hydroquinone diglycidyl ether, and the like.
In addition to these, the compounds described on pages 3 to 6 of the above-mentioned document “Polymer Processing”, separate volume epoxy resin, can be mentioned.

Examples of other aliphatic unsubstituted epoxy compounds include Denarex R-45EPT (manufactured by Nagase ChemteX Corporation), Epofriend AT501, CT310, Epolide PB3600 (above, Daicel Chemical Industries, Ltd.), KL-630. [Kuraray Co., Ltd.], Tetrad C [Mitsubishi Gas Chemical Co., Ltd.], TEPIC [Nissan Chemical Industry Co., Ltd.] and the like.

Examples of alicyclic epoxy compounds include dicyclopentadiene dioxide, limonene dioxide, 4-vinylcyclohexene dioxide, 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate, bis (3,4 -Epoxycyclohexylmethyl) adipate, 3,4-epoxycyclohexylmethyl (meth) acrylate and the like.
In addition to these, the document “Epoxy Resin-Recent Advances” (Shojodo, published in 1990), Chapter 2 and the document “Polymer Processing”, Vol. 9, Volume 22 Epoxy Resin (Polymer Publishing) Compounds published on pages 7 and 18 to 20 of the Society).

An oxetane compound is a compound having one or more oxetane rings in the molecule. Specific examples include various oxetane compounds described in JP-A-8-85775 and JP-A-8-134405, and among these, compounds having one or more oxetanyl groups are preferable. Examples of monofunctional oxetanes include 3-ethyl-3- (hydroxymethyl) oxetane, 3-ethyl-3-[(phenoxy) methyl] oxetane, 3-ethyl-3- (hexyloxymethyl) oxetane, 3-ethyl -3- (2-ethylhexyloxymethyl) oxetane, 3-ethyl-3- (chloromethyl) oxetane and the like. Examples of the bifunctional oxetane include 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, bis {[1-ethyl (3-oxetanyl)] methyl} ether, and the like.

A vinyl ether compound is a compound having one or more vinyl ether groups in the molecule. Specifically, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, 2-hydroxyethyl vinyl ether, cyclohexanedimethanol monovinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether, cyclohexyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, lauryl Vinyl ether, cetyl vinyl ether, 2-ethylhexyl vinyl ether, monofunctional vinyl ethers such as 2- (2-vinyloxyethoxy) ethyl (meth) acrylate, 1,4-butanediol divinyl ether, cyclohexanedimethanol divinyl ether, diethylene glycol divinyl ether, Multifunctional vinyl such as triethylene glycol divinyl ether Ether and the like.

The compound other than the component (A) having one or more cationically polymerizable groups in the molecule is preferably a low molecular weight compound because it can increase the adhesiveness and can reduce the viscosity. A compound having a molecular weight of 2,000 or less is preferred. Particularly preferred examples include limonene dioxide, 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate, 3-ethyl-3- (hydroxymethyl) oxetane, 3-ethyl-3-[(phenoxy) Methyl] oxetane and bis (3-ethyl-3-oxetanylmethyl) ether.

In addition to the above, the composition of the present invention can be blended with other components usually used in adhesive compositions.

Specifically, silane coupling agents, inorganic fillers, softeners, antioxidants, anti-aging agents, stabilizers, tackifying resins, leveling agents, antifoaming agents, plasticizers, organic solvents, dyes, pigments, treatments Inactive ingredients such as agents and UV screening agents can be blended. Examples of the tackifying resin include rosins such as rosin acid, polymerized rosin acid and rosin acid ester, terpene resin, terpene phenol resin, aromatic hydrocarbon resin, aliphatic saturated hydrocarbon resin, and petroleum resin.

Examples of the silane coupling agent include 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltri Ethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, N -2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxy Lan, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, Examples include 3-mercaptopropyltrimethoxysilane. A silane coupling agent can use only 1 type of an above described compound, or can also use 2 or more types together.

The composition of the present invention can be produced by stirring and mixing the components (A) to (C) and, if necessary, the component (D) or other components according to a conventional method.
In this case, heating can be performed as necessary. The heating temperature may be appropriately set according to the composition to be used, the substrate, the purpose, etc., but is preferably 30 to 80 ° C.

The viscosity of the composition is preferably 10 to 1000 mPa · s from the viewpoint of excellent coatability on the substrate.

The composition of the present invention can be used for adhesion between plastic films and the like, and adhesion between plastic films and the like and various other substrates (hereinafter referred to as other substrates).
In the following, when simply described as “base material”, it means a general term for plastic films and other base materials.
Other examples of the substrate include paper and metal.
The method of using the composition of the present invention may be in accordance with a conventional method, and specific examples include a method of applying to a base material, pasting with another base material, and irradiating active energy rays.

Examples of the material in the plastic film include polyvinyl chloride resin, polyvinylidene chloride, cellulosic resin, polyethylene, polypropylene, polystyrene, ABS resin, polyamide, polyester, polycarbonate, polyurethane, polyvinyl alcohol, triacetyl cellulose, cycloolefin polymer, Examples include polymethyl methacrylate, acrylic / styrene resin, ethylene-vinyl acetate copolymer, and chlorinated polypropylene.
Examples of the paper include imitation paper, fine paper, craft paper, art coated paper, caster coated paper, pure white roll paper, parchment paper, water resistant paper, glassine paper, and corrugated paper.
Examples of the metal foil include aluminum foil.

Coating on the substrate may be performed by a conventionally known method, natural coater, knife belt coater, floating knife, knife over roll, knife on blanket, spray, dip, kiss roll, squeeze roll, reverse roll, air blade , Curtain flow coater, comma coater, gravure coater, micro gravure coater, die coater and curtain coater.
The coating thickness of the composition of the present invention may be selected according to the substrate used and the application, but is preferably 0.1 to 100 μm, more preferably 1 to 25 μm.

Examples of the active energy rays include visible light, ultraviolet rays, X-rays, and electron beams, but ultraviolet rays are preferable because inexpensive devices can be used.
Various light sources can be used as the light source when cured by ultraviolet rays, and examples thereof include a pressurized or high pressure mercury lamp, a metal halide lamp, a xenon lamp, an electrodeless discharge lamp, a carbon arc lamp, and an LED.
In the case of curing with an electron beam, various devices can be used as an EB irradiation device that can be used, such as a Cockloft-Waltsin type, a bandegraph type, and a resonance transformer type device. Those having an energy of 1000 eV are preferred, and more preferably 100 to 300 eV.

The composition of the present invention is suitable for bonding a thin layer adherend as a substrate.
The method of use for adhering the thin-layer adherend may be in accordance with a method usually used in the production of laminates.
For example, a method in which the composition is applied to a first thin-layer adherend, dried as necessary, and then a second thin-layer adherend is bonded thereto and irradiated with active energy rays. Is mentioned.

Examples of the thin layer adherend include plastic film, paper, metal foil, and the like.
The plastic film or the like needs to be capable of transmitting active energy rays, and the film thickness may be selected according to the thin layer adherend to be used and the use, but preferably the thickness is 0.2 mm or less. is there.

Among these thin layer adherends, the composition of the present invention is preferably used for adhesion between plastic films and the like, and more preferably used for hydrophilic plastics, specifically, those made of polyvinyl alcohol or triacetyl cellulose. be able to.

Also, before bonding the adherend, an activation treatment can be performed on one or both surfaces in order to increase the interlayer adhesion. Examples of the surface activation treatment include plasma treatment, corona discharge treatment, chemical treatment, surface roughening treatment and etching treatment, and flame treatment, and these may be used in combination.

Coating on the thin layer adherend may be performed according to a conventionally known method, and examples thereof include the same method as described above.
The coating thickness of the composition of the present invention may be selected according to the thin layer adherend to be used and the application, but the same coating thickness as described above is preferable.

In this case, the bonding can be performed not only in a flat state but also in a curved surface state.
That is, there is a method in which the base material is folded into a concave state or a convex state, the composition is applied in this state, the other base material is bonded, and active energy rays are irradiated.
As another method, there is a method in which the composition of the present invention is applied in a planar state, the other substrate is bonded, folded into a concave state or a convex state, and irradiated with active energy rays to adhere. Can be mentioned.
In this case, as a method for applying the composition in a planar state, the above-described method may be followed. Examples of the method of coating the composition in a curved surface include a method using a spray, dip, curtain flow coater, screen printing, slot die coater and the like.

By the above method, a laminate composed of a plastic film / cured product of the composition of the present invention / plastic film and a laminate composed of a plastic film / cured product of the composition of the present invention / other substrates are produced. The
Laminates such as a laminate film obtained from the composition of the present invention are excellent in adhesive strength under high temperature and high humidity conditions. Therefore, optical films such as polarizing plates, protective films and retardation films used in liquid crystal display devices, etc. It can be suitably used for a film.
Especially the composition of this invention can be preferably used for manufacture of a polarizing plate and a polarizing plate with retardation film. Hereinafter, the manufacturing method of a polarizing plate is demonstrated.

In the present specification, a polarizer means a film or film having a polarizing function described later, and a polarizing plate is a polarizer with a protective layer in which one or both sides of the polarizer are protected by a film or film. Represents that. Moreover, a polarizing plate with a retardation film represents a polarizer or a polarizing plate in which a retardation film is bonded or a film having a retardation function is formed by coating.

As described above, the composition of the present invention can be preferably used for adhesion of hydrophilic plastics. In the production of polarizing plates, polyvinyl alcohol used as a polarizer and triacetyl cellulose used as a protective film for a polarizer are hydrophilic. Corresponds to plastic.

The composition of the present invention can be used for adhesion between a polarizer and a protective film and adhesion between a polarizing plate and a retardation film.

A polarizer has a function of selectively transmitting linearly polarized light in one direction from natural light.
Specific examples of polarizers include iodine polarizers in which iodine is adsorbed and oriented on a polyvinyl alcohol film, dichroic dyes in which dichroic dye is adsorbed and oriented on a polyvinyl alcohol film, and (lyotropic) liquid crystal Examples thereof include a coating type polarizer coated with a dye in a state, oriented and fixed.
These iodine-based polarizers, dye-based polarizers, and coating-type polarizers have the function of selectively transmitting one direction of linearly polarized light from natural light and absorbing the other direction of linearly polarized light. It is called a type polarizer.

In the iodine-based polarizer and the dye-based polarizer, a protective layer is usually provided on one side or both sides thereof, but the composition of the present invention can be used for adhesion between the polarizer and the protective film.

Examples of protective films used in the protective layer include cellulose acetate resin films such as triacetyl cellulose and diacetyl cellulose, acrylic resin films, polyester resin films, polyarylate resin films, polyether sulfone resin films, and cyclic rings such as norbornene. Examples thereof include cyclic polyolefin resin films containing olefin as a monomer.

Next, the composition of this invention can also be used for adhesion | attachment of a polarizing plate and retardation film.
In this case, a polarizing plate having a protective layer on one side or both sides can be used.
In this case, the protective layer may be one obtained by bonding the protective film or a protective film formed by coating.
In a polarizing plate provided with a protective layer only on one side, the surface to be bonded to the retardation film may be a surface with a protective layer or a surface without a protective layer.

Various types of retardation films can be used. Optical films that have been subjected to processing such as uniaxial or biaxial stretching, or liquid crystal compounds are applied to a substrate, and processed to be oriented and fixed. An optical film or the like is mentioned, and the magnitude relationship (refractive index ellipsoid) of the three-dimensional refractive index is controlled according to the use conditions. It is mainly used to compensate for coloration of the liquid crystal layer of a liquid crystal display and to compensate for changes in phase difference due to viewing angle.

Specific examples of retardation films include optical film materials that are subjected to processing such as stretching, such as polyolefins such as polyethylene, polypropylene, and cyclic polyolefins, polycarbonate, polyvinyl alcohol, polystyrene, polymethyl methacrylate, and polyarylate. And polyamide.
The above-mentioned cyclic polyolefin is a general generic name for resins obtained from cyclic olefins such as norbornene, tetracyclododecene, and derivatives thereof. For example, JP-A-3-14882 and JP-A-3-122137. Etc. are mentioned.
Specifically, a cyclic olefin ring-opening polymer, a cyclic olefin addition polymer, a random copolymer of a cyclic olefin and an α-olefin such as ethylene or propylene, or these are modified with an unsaturated carboxylic acid or a derivative thereof. Examples of such graft-modified products can be given. Furthermore, these hydrides are mentioned. Examples of the products include ZEONEX and ZEONOR manufactured by Nippon Zeon Co., Ltd., Arton manufactured by JSR Corporation, and TOPAS manufactured by TICONA.

In addition, as optical films coated with liquid crystalline compounds, etc., and oriented and fixed, "WV film" (Fuji Film Co., Ltd.), "LC film", "NH film" [Both manufactured by JX Nippon Oil & Energy Corporation] and the like.

A method for producing a polarizing plate or a polarizing plate with a retardation film using the composition of the present invention will be described.
Examples of the production method include a method including the following steps [1] to [3].
[1] A step of applying the composition of the present invention to any one of a polarizer, a polarizing plate, a protective film, a protective film, a retardation film, and a retardation film as an adherend,
[2] A step of laminating one of a polarizer, a polarizing plate, a protective film, a protective film, a retardation film, and a retardation film, which is the other adherend, to the film coated with the composition,
[3] A step of irradiating an active energy ray through a substrate coated with the composition of the present invention after the films are bonded together.
When the protective film or retardation film is bonded to only one side, a polarizing plate or a polarizing plate with a retardation film can be produced by the above procedure, but when bonding to both sides, the steps [1] and [2 ] May be repeated after repeating step [3], or steps [1], [2] and [3] may be repeated twice.

The coating method in the step [1] and the active energy ray irradiation method in the step [3] may be performed by the same method as described above.
Further, as described above, it can be bonded in a curved state.

When using a polarizing plate with a retardation film as a circularly polarizing plate, in order to obtain a circularly polarized state over a wide band, a retardation film having a different retardation is further pasted on the retardation film side of the polarizing plate with a retardation film. It can also be combined.
Specifically, a method of laminating a retardation film having a ½ wavelength with respect to each wavelength and further laminating a retardation film having a ¼ wavelength with respect to each wavelength to the polarizer film. is there. In this case, step [3] may be performed after steps [1] and [2] are repeated three times, or steps [1], [2] and [3] may be repeated three times.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. In the following examples, “parts” means parts by weight.

○ Production Example 1
Methyl epichlorohydrin (hereinafter referred to as “MECH”) was produced according to the method described in Synthesis Example 1 of Japanese Patent No. 4251138 (hereinafter referred to as “Patent Document 8”).

○ Production Example 2 [Production of component (A)]
Using MECH and bisphenol F obtained in Production Example 1 and following the method described in Example 10 of Patent Document 8, a bisphenol F dimethylglycidyl ether derivative [in the formula (6), R ₁ is a methyl group, n is 0 Compound. Hereinafter, “BFMGE” was manufactured.
The obtained compound was a mixture of the following three compounds.

○ Production Example 3 [Production of Component (A)]
Using the MECH and resorcinol obtained in Production Example 1 and following the method described in Example 9 of Patent Document 8, a resorcinol-dimethylglycidyl ether derivative [in the formula (5), R ₁ is a methyl group, n is 0 Compound. Hereinafter, it was referred to as “RMGE”.

○ Production Example 4 [Production of component (A)]
Using the MECH and phenol obtained in Production Example 1 and following the method described in Example 1 of Patent Document 8, phenyl-methyl glycidyl ether [in the formula (8), R ₁ is a methyl group compound. Hereinafter, “PMGE”) was manufactured.

○ Examples 1 to 6 and Comparative Examples 1 to 6
According to the formulation shown in Table 1 and Table 2 below, the components (A) to (D) and other components were dissolved by heating and stirring at 60 ° C. for 1 hour to produce an active energy ray-curable adhesive composition.

In Tables 1 and 2, the numbers of each component of the composition mean parts. The abbreviations in Tables 1 and 2 mean the following, except for those defined above.
1) Component (B) · HBA: 4-hydroxybutyl acrylate, Osaka Organic Chemical Industry Co., Ltd. Biscoat 4-HBA (trade name)
-PEA: Phenoxyethyl acrylate, Kyoeisha Chemical Co., Ltd. light acrylate PO-A (trade name)
2) Component (C) Irg250: Iodonium salt photocationic initiator, Irgacure 250 (trade name) manufactured by BASF Japan
3) Component (D) DETX: 2,4-diethylthioxanthone, Nippon Kayaku Co., Ltd. DETX-S (trade name)
4) Other components jER: Diglycidyl ether of bisphenol F, jER-807 (trade name) manufactured by Japan Epoxy Resin Co., Ltd.
EX-201: resorcinol diglycidyl ether, Denacol EX-201 (trade name) manufactured by Nagase ChemteX Corporation
CEL2021: 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexenecarboxylate, Daicel Chemical Industries, Ltd. Celoxide 2021P (trade name)
OXT211: 3-ethyl-3-phenoxymethyloxetane, Aron Oxetane OXT-211 (trade name) manufactured by Toagosei Co., Ltd.

● Evaluation The obtained composition was evaluated according to the following test method. The results are shown in Tables 1 and 2.

(25 ° C viscosity)
The viscosity of the composition at 25 ° C. was measured using an E-type viscometer.
In the case of thin film coating with a coater, the lower the 25 ° C. viscosity, the better.
○: Less than 100 mPa · s, Δ: 100 to 200 mPa · s, ×: Over 200 mPa · s

(Manufacture of laminates)
The resulting composition was applied to a 50 μm thick PET film (trade name Cosmo Shine A-4300, manufactured by Toyobo Co., Ltd.) with a bar coater to a thickness of 2 μm. A glass plate was bonded to this.
Thereafter, from the glass side, using an 80 W / cm condensing type metal halide lamp, ultraviolet rays were irradiated for one pass at a conveyor speed of 30 m / min to cure, thereby producing a laminate.
The ultraviolet intensity was 233 mW / cm ² and the integrated light amount was 114 mJ / cm ² (both values at 365 nm).

(Peel strength)
The peel strength of the obtained laminate was measured under the following conditions.
・ Tensile testing machine: Instron 5564 manufactured by Instron Japan Company Limited
-Test piece: 25 mm x 100 mm
Test method: 180 degree peeling and peeling speed: 200 mm / min

As is apparent from Table 1, the composition of the present invention had a low viscosity and an excellent peel strength. On the other hand, the composition not containing the component (A) of the present invention (Comparative Examples 1 to 5) and the composition not containing the component (B) (Comparative Example 6) have at least one of viscosity and peel strength. Was insufficient.

○ Examples 7 to 16 and Comparative Examples 7 to 15
According to the formulations shown in Table 3 and Table 4 below, the components (A) to (D) and other components were dissolved by heating and stirring at 60 ° C. for 1 hour to produce an active energy ray-curable adhesive composition.

In Table 3 and Table 4, the number of each component of the composition means the number of parts. The abbreviations in Tables 3 and 4 mean the following, except for those defined above.
1) Component (B) HPA: 2-hydroxypropyl acrylate, Kyoeisha Chemical Co., Ltd. light ester HOP-A (trade name)
M313: Isocyanuric acid EO-modified di / triacrylate, Aronix M-313 (trade name) manufactured by Toagosei Co., Ltd.
M203: Tricyclodecane dimethanol diacrylate, Aronix M-203S (trade name) manufactured by Toagosei Co., Ltd.
M325: ε-caprolactone-modified tris (acryloxyethyl isocyanurate), Aronix M-325 (trade name) manufactured by Toagosei Co., Ltd.
M-270: Polypropylene glycol (n≈12) diacrylate, Aronix M-270 (trade name) manufactured by Toagosei Co., Ltd.
-PEA: Phenoxyethyl acrylate, Kyoeisha Chemical Co., Ltd. light acrylate PO-A (trade name)
-IBXA: Isobornyl acrylate, Kyoeisha Chemical Co., Ltd. light acrylate IB-XA (trade name)
THFA: Tetrahydrofurfuryl acrylate, Osaka Organic Chemical Industry Co., Ltd. Biscoat # 150 (trade name)
2) Component (C) -CPI: 50% by weight propylene carbonate solution of sulfonium salt photocation initiator, CPI-100P (trade name) manufactured by San Apro
DBA: 9,10-dibutoxyanthracene, Kawasaki Kasei Anthracure UVS-1331 (trade name)
3) Other components YX: Diglycidyl ether of hydrogenated bisphenol A, YX-8000 (trade name) manufactured by Japan Epoxy Resin Co., Ltd.
100 MF: trimethylolpropane triglycidyl ether, Epolite 100MF (trade name) manufactured by Kyoeisha Chemical Co., Ltd.
CEL3000: Limonene dioxide, Daicel Chemical Industries, Ltd. Celoxide 3000 (trade name)
OXT221: 3-ethyl-3 {[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane, Aron Oxetane OXT-221 (trade name) manufactured by Toagosei Co., Ltd.
SM100: 3,4-epoxycyclohexylmethyl methacrylate, Daicel Chemical Industries Cyclomer M-100 (trade name)

● Evaluation The obtained composition was evaluated according to the following test method. The results are shown in Tables 5 and 6.

(25 ° C viscosity)
The viscosity was measured using an E-type viscometer in the same manner as described above.

(Polarizer Production Example 1)
A dyeing solution was prepared by dissolving 0.05 parts by mass of iodine and 0.5 parts by mass of potassium iodide in 100 parts by mass of water. The dyeing solution was heated to 55 ° C., a PVA film (Kuraray vinylon film VF-PS, 75 μm) was immersed for 1 minute, and the film was stretched 6 times in one direction. Furthermore, washing after dyeing was performed in an aqueous solution in which 4 parts by mass of boric acid and 6 parts by mass of potassium iodide were dissolved in 90 parts by mass of water, and then dried to prepare a polarizer having a thickness of 30 μm.

(Polarizing plate production example 1)
On a triacetylcellulose film containing UV absorber with a thickness of 80 μm (trade name: Fujitac, manufactured by Fuji Film Co., Ltd., hereinafter referred to as “UVA-TAC”), corona treatment (Navitas Polydyne 1, output 0. 1 kW, treatment speed 1 second / cm).
Subsequently, the active energy ray-curable adhesive composition was applied to the polarizer obtained in Production Example 1 to a thickness of 5 μm with a bar coater. This was laminated with corona-treated UVA-TAC, then turned over, and similarly coated with an active energy ray-curable adhesive composition and corona-treated UVA-TAC. After that, using an 80 W / cm condensing type metal halide lamp, ultraviolet rays were irradiated on each of the front and back surfaces at a conveyor speed of 5 m / min for curing. Thereafter, it was cured at room temperature for 12 hours or more to produce a TAC polarizing plate as a test specimen. The ultraviolet intensity was 250 mW / cm ² and the integrated light quantity was 100 mJ / cm ² (both values at 365 nm).

(Polarizing plate production example 2)
A polarizing plate was prepared in the same manner as in Production Example 1 of the polarizing plate, except that a triacetyl cellulose film (manufactured by LOFO, hereinafter referred to as “TAC”) having a thickness of 100 μm and containing no UV absorber was used instead of UVA-TAC. Was made.

(Peel strength)
The specimen obtained in Production Example 1 of the polarizing plate was cut into a length of 100 mm and a width of 25 mm, and attached to glass using a base material-free double-sided tape 465 made by Sumitomo 3M. The layer structure of the laminate is (UVA-TAC (1) / adhesive / polarizer / adhesive / UVA-TAC (2) / double-sided tape / glass) from the top. The peel strength between the polarizer and TAC (2) of the obtained laminate was measured under the following conditions. Similarly, the peel strength of the test body obtained in Production Example 2 of the polarizing plate was also measured.
・ Tensile testing machine: Instron 5564 manufactured by Instron Japan Company Limited
-Test piece: 25 mm x 100 mm
Test method: 90 degree peeling / peeling speed: 200 mm / min

(Moisture and heat resistance)
The specimens obtained in Production Examples 1 and 2 of the polarizing plate were placed in a constant temperature and humidity chamber of 60 ° C./90% RH for 500 to 1000 hours, and changes in appearance were observed.
○: No decolorization △: Some decolorization is observed ×: Almost complete decolorization

(Film curl)
In polarizing plate production examples 1 and 2, the uncured laminate after completion of UV curing was cut into a width of 50 mm and a length of 100 mm, and attached to a 3-inch paper tube using a cellophane tape. Thereafter, the film was cured at room temperature for 12 hours or more, and the film was removed and placed on a horizontal desk, and the film appearance was observed.
○: Warp height of film edge is less than 1 cm ×: Warp height of film edge is 1 cm or more

As is apparent from Table 5, the composition of the present invention has a low viscosity, excellent peel strength and appearance after a high humidity test, and curling of the film derived from a dark reaction after UV curing is also suppressed. Met.
On the other hand, as is clear from Table 6, compositions (Comparative Examples 8 to 15) that do not contain the component (A) of the present invention and compositions (Comparative Example 7) that do not contain the component (B) At least one of the peel strength and the appearance after the high-humidity test was insufficient.

The composition of the present invention can be used as an adhesive for various plastic films, especially as an adhesive for hydrophilic plastics, and is particularly suitable for the production of optical films such as liquid crystal display devices, particularly for the production of polarizing plates. Can be used.

Claims (16)

1. An activity comprising at least a curable component and a polymerization initiator, wherein the curable component is composed of at least the following components (A) and (B), and the polymerization initiator is composed of at least the following component (C): Energy ray curable adhesive composition.
   (A) component: following formula (1)
   

   

   
   (In the formula (1), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, m is an integer of 1 to 20, and R ₂ is a linear chain having 1 to 20 carbon atoms. Or branched aliphatic alcohols and their alkylene oxide modified products, linear or branched polyalkylene oxides, polyester polyols, aromatic alcohols and their alkylene oxide modified products, and compounds having phenolic hydroxyl groups and their alkylene oxide modified products M-valent residue of a compound selected from the group consisting of compounds may contain —OCH ₂ C (OH) (R ₁ ) CH ₂ O— units.
   A compound represented by
   Component (B): an ethylenically unsaturated compound.
   Component (C): a cationic photopolymerization initiator.
2. In a total amount of 100% by weight of the curable component, 20 to 70% by weight of the component (A) and 30 to 80% by weight of the component (B) are included.
   The active energy ray-curable adhesive composition according to claim 1, comprising 0.1 to 20 parts by weight of the component (C) with respect to 100 parts by weight of the total amount of the curable component.
3. The component (A) is a compound represented by the formula (1), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, m is 1 or 2, R ₂ is a m-valent residue of a compound having a phenolic hydroxyl group or a modified alkylene oxide thereof, and may contain a —OCH ₂ C (OH) (R ₁ ) CH ₂ O— unit. Item 3. The active energy ray-curable adhesive composition according to Item 1 or 2.
4. The active energy ray-curable adhesive composition according to claim 3, wherein the compound having a phenolic hydroxyl group of R _{2 in} the component (A) is selected from the group consisting of phenol, biphenol, bisphenol, and a phenol resin.
5. The active energy ray-curable adhesive composition according to claim 4, wherein the component (A) is a compound represented by the following formula (5), (6), or (8).
   

   

   
   (In Formula (5), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, and n is 0 or a positive number.)
   

   

   
   (In Formula (6), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, and n is 0 or a positive number.)
   

   

   
   (In Formula (8), R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms)
6. The active energy ray-curable adhesive composition according to any one of claims 1 to 5, wherein the component (B) contains (b1) an ethylenically unsaturated compound having a hydroxyl group.
7. The active energy ray-curable adhesive composition according to claim 6, comprising 10 to 40% by weight of the component (b1) in 100% by weight of the total amount of the curable component.
8. The adhesive composition according to any one of claims 1 to 7, wherein the component (B) comprises (b2) a compound having two or more ethylenically unsaturated groups in the molecule.
9. The active energy ray-curable adhesive composition according to claim 8, comprising 1 to 50% by weight of the component (b2) in 100% by weight of the total amount of the curable component.
10. The active energy ray-curable adhesive composition according to any one of claims 1 to 9, wherein the polymerization initiator further comprises (D) a photoradical polymerization initiator.
11. The active energy ray-curable adhesive composition according to claim 10, comprising 0.1 to 20 parts by weight of the component (D) with respect to 100 parts by weight of the total amount of the curable component.
12. The active energy ray-curable adhesive composition according to any one of claims 6 to 11, which is used for adhesion of a hydrophilic plastic film or sheet.
13. The active energy ray-curable adhesive composition for producing a polarizing plate according to claim 12, wherein the hydrophilic plastic film or sheet is a polyvinyl alcohol polarizer film or sheet.
14. A laminate comprising a substrate, a cured product layer of the composition according to any one of claims 1 to 11, and a plastic film or sheet laminated in this order.
15. The laminate according to claim 14, wherein the substrate is a plastic film or sheet.
16. A polarizing plate comprising a polyvinyl alcohol-based polarizer film or sheet, a cured product layer of the composition according to any one of claims 1 to 11 and a plastic film or sheet laminated in this order.