KR20180021058A - Bonding agent, bonded body, and method for manufacturing bonded body - Google Patents

Abstract

An active energy ray curing type adhesive comprising a PVA polymer (A), a cationic polymerizable compound (B) and a cationic polymerization initiator (C) as an adhesive for bonding a protective film and a film containing a PVA polymer An adhesive body comprising a film containing a PVA polymer, a protective film, a film comprising a PVA polymer, and an adhesive layer disposed between the protective film and the adhesive layer, wherein the adhesive layer is formed from the adhesive; And a method for producing an adhesive body wherein a film including a PVA polymer and a protective film are laminated via the adhesive agent, and then an active energy ray is irradiated to cure the adhesive agent. As a result, it is possible to provide an adhesive which is capable of obtaining an adhesive body such as a polarizing plate exhibiting a high adhesive force in adhesion between a film containing a PVA polymer and a protective film and having excellent water resistance, an adhesive body obtained by using the adhesive, Can be provided.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a bonding agent, a bonding agent,

INDUSTRIAL APPLICABILITY The present invention relates to an adhesive agent which exhibits a high adhesive force in adhesion between a protective film and a film comprising a polyvinyl alcohol polymer (hereinafter, sometimes abbreviated as " PVA "), , An adhesive body obtained by using the adhesive, and a method for producing the adhesive body.

A polarizing plate having light transmission and shielding functions is a fundamental component of a liquid crystal display (LCD) together with a liquid crystal that changes the polarization state of light. Many polarizing plates have a structure in which a protective film such as a cellulose triacetate (TAC) film is stuck to the surface of a polarizing film. As the polarizing film constituting the polarizing plate, a PVA polymer film is uniaxially stretched, (I ₃ ^- or I ₅ ^- ) and dichroic organic dyes are adsorbed on a stretched film made of polyvinylidene fluoride. Such a polarizing film is usually obtained by uniaxially stretching a PVA polymer film previously containing a dichroic dye or by adsorbing a dichroic dye at the same time as uniaxial stretching of a PVA polymer film, And then the dichroic dye is adsorbed after the axial stretching.

The LCD is intended to be used in a wide range of small-sized devices such as an electronic desk calculator and a wrist watch, a notebook personal computer, a liquid crystal monitor, a liquid crystal color projector, a liquid crystal television, a vehicle navigation system, a mobile phone, In recent years, there have been many cases in which the polarizing plates are used for mobile applications such as small-sized notebook personal computers and mobile phones.

One of the methods for making the polarizing plate thin is to thin the polarizing film or the protective film. However, when these films are made thin, there arises a problem that the durability and the water resistance of the polarizing plate are lowered. Therefore, in recent years, it has been proposed to use, as a protective film, a (meth) acrylic polymer film, a polyester film, a polymer film containing an alicyclic structure, or the like instead of the conventional TAC film having high moisture permeability.

For example, a cationic polymerizable adhesive containing a hyperbranched polyol having 10 or more hydroxyl groups (see Patent Document 1) can be used as an adhesive used for bonding a polarizing film when the polarizing plate is manufactured using such a protective film, , A radiation curable composition containing a compound having a number average molecular weight of 500 or more and containing two or more hydroxyl groups (see Patent Document 2), and the like are known.

Japanese Laid-Open Patent Publication No. 2008-111105 Japanese Laid-Open Patent Publication No. 2009-227804

However, since the adhesive described in Patent Document 1 contains a multi-branched polyol having poor solubility in the monomer, the uniformity of the adhesive is deteriorated and the adhesive force between the polarizing film and the protective film in the polarizing plate surface is uneven, As a result, the adhesive force tends to decrease. Also, the adhesive described in Patent Document 2 has a problem that the adhesive force between the polarizing film and the protective film is low, and the durability and water resistance of the polarizing plate are deteriorated.

The present invention relates to an adhesive capable of obtaining an adhesive body such as a polarizing plate exhibiting a high adhesive force in adhesion between a protective film and a film containing a PVA polymer such as a polarizing film and having excellent water resistance, And a process for producing the adhesive agent.

DISCLOSURE OF THE INVENTION The inventors of the present invention have made intensive investigations in order to achieve the above object. As a result, it has been found that in the case of an active energy ray curable adhesive, a PVA polymer (A) such as PVA or polyvinyl butyrate, (B) and the cation polymerization initiator (C), it is possible to improve the adhesion between the film containing the PVA polymer to be adhered and the protective film, and further improve the water resistance. The present inventors have completed the present invention.

That is,

[1] An adhesive for bonding a protective film and a film containing a PVA polymer, which comprises an active energy ray (A) containing a PVA polymer (A), a cationic polymerizable compound (B) and a cationic polymerization initiator Curable adhesive;

[2] The adhesive of [1], further comprising a radical polymerizing compound (D) and a radical polymerization initiator (E);

[3] The adhesive according to the above [1] or [2], wherein at least a part of the cationically polymerizable compound (B) is a compound (BD) which is cationically polymerizable as well as a radically polymerizable compound;

[4] The polyvinyl alcohol composition according to any one of [1] to [3], wherein the polyvinyl alcohol polymer (A) is a polyvinyl alcohol having an acetalized vinyl alcohol unit content of less than 10 mol% and a saponification degree of 80 mol% Any one adhesive;

[5] The adhesive according to any one of [1] to [3], wherein the polyvinyl alcohol-based polymer (A) is polyvinyl acetal having an acetalized vinyl alcohol unit content of 10 mol% or more;

[6] The adhesive according to [5], wherein the polyvinyl acetal is polyvinyl butyral;

[7] The adhesive according to any one of [1] to [6], wherein the content of the polyvinyl alcohol polymer (A) is 1 to 90% by mass;

[8] An adhesive body comprising a film comprising a polyvinyl alcohol-based polymer, a protective film and an adhesive layer, wherein the adhesive layer is disposed between the film containing the polyvinyl alcohol-based polymer and the protective film, Wherein the layer is obtained by curing the adhesive of any one of the above [1] to [7];

[9] The adhesive of [8], wherein the film comprising the polyvinyl alcohol-based polymer is a stretched film;

[10] The adhesive according to [8] or [9], wherein the stretched film is a polarizing film or a retardation film.

[11] The adhesive material according to any one of [8] to [10], wherein the protective film comprises triacetyl cellulose, a (meth) acrylic polymer, a polyester or a polymer containing an alicyclic structure;

[12] The adhesive according to any one of [8] to [11], wherein the adhesive force between the film containing the polyvinyl alcohol-based polymer and the protective film is 6.0 N / 25 mm or more;

[13] A process for producing a laminated film, which comprises adhering a film comprising a polyvinyl alcohol polymer and a protective film via an adhesive of any one of [1] to [7], and then curing the adhesive layer by irradiating active energy rays A method for producing a sieve;

.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an adhesive which shows a high adhesive force in adhesion between a film containing a PVA polymer and a protective film and which can obtain an adhesive body excellent in water resistance, an adhesive body obtained by using the adhesive, A manufacturing method is provided.

Fig. 1 is a cross-sectional view schematically showing an example of the adhesive agent of the present invention.

Hereinafter, the present invention will be described in detail.

<Adhesive>

The adhesive of the present invention is an active energy ray curable adhesive for adhering a protective film and a film containing a PVA polymer, wherein the PVA polymer (A), the cationic polymerizable compound (B) and the cationic polymerization initiator (C ). Examples of the active energy ray include electron beams, proton rays, neutron rays, and the like, as well as electromagnetic waves such as ultraviolet rays, infrared rays, X-rays, and gamma rays. Of these, ultraviolet rays or electron rays are preferable, and ultraviolet rays are more preferable from the viewpoints of the curing rate, the availability of the irradiation apparatus, and the price. When the adhesive of the present invention is irradiated with active energy rays, the cationic polymerization initiator (C) contained therein is excited, and the reaction between the cationic polymerizable compounds (B) proceeds. In this process, the PVA polymer (A) can be cured together with the cationic polymerizable compound (B) and the polymer thereof, and an adhesive layer can be formed. Further, in the present invention, for the sake of distinguishing the PVA polymer contained in the adhesive from the PVA polymer constituting the film comprising the PVA polymer to be bonded by the adhesive, for convenience, the PVA polymer contained in the adhesive Referred to as &quot; PVA polymer (A) &quot;.

[PVA Polymer (A)]

Examples of the PVA polymer (A) contained in the adhesive of the present invention include vinyl acetate, vinyl formate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl versatate, vinyl laurate, vinyl stearate, vinyl benzoate, And polyvinyl esters obtained by polymerizing one or more kinds of vinyl esters such as phenyl. Of the above vinyl esters, compounds having a vinyloxycarbonyl group (H ₂ C = CH-O-CO-) in the molecule are preferable from the viewpoints of ease of production of PVA polymer, Is more preferable.

The above-mentioned polyvinyl ester is preferably obtained by using only one kind of vinyl ester or two or more kinds of vinyl esters as monomers, more preferably obtained by using only one kind of vinyl ester as a monomer, It may be a copolymer of one or more vinyl esters and other monomers copolymerizable therewith.

Examples of the other monomer copolymerizable with the vinyl ester include (meth) acrylic acid or a salt thereof, (meth) acrylate such as methyl (meth) acrylate, Propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t- (Meth) acrylate, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, (Meth) acrylamide propylsulfonic acid or its salt, (meth) acrylamidopropyldimethylamine or its salt, N, N-dimethyl (meth) acrylamide, diacetone (Meth) acrylamide derivatives such as acrylamide or derivatives thereof; Propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, N-vinyl pyrrolidone, Vinyl ethers such as butyl vinyl ether, t-butyl vinyl ether, dodecyl vinyl ether and stearyl vinyl ether, vinyl cyanide such as (meth) acrylonitrile, vinyl chloride, vinylidene chloride, vinyl fluoride and vinylidene fluoride Allyl compounds such as allyl acetate and allyl chloride, maleic acid or its salts, esters or acid anhydrides, itaconic acid or its salts, esters or acid anhydrides, vinylsilyl compounds such as vinyltrimethoxysilane, Salts and the like. The above-mentioned polyvinyl esters may have a structural unit derived from one or more of the above-mentioned other monomers.

The proportion of the structural unit derived from the other monomer in the polyvinyl ester is preferably 15 mol% or less, more preferably 10 mol% or less, based on the number of moles of the total structural units constituting the polyvinyl ester , And still more preferably 5 mol% or less.

As the PVA polymer (A), those not subjected to graft copolymerization can be preferably used. However, if the PVA polymer (A) is within the range not significantly hindering the effect of the present invention, the PVA polymer (A) It may be one modified by a possible monomer. The graft copolymerization can be carried out on at least one of a polyvinyl ester and a PVA polymer obtained by saponifying it. Examples of the graft copolymerizable monomer include an unsaturated carboxylic acid or a derivative thereof, an unsaturated sulfonic acid or a derivative thereof, and an -olefin having 2 to 30 carbon atoms. The proportion of the structural unit derived from the graft copolymerizable monomer in the polyvinyl ester or the PVA polymer is preferably 5 mol% or less based on the number of moles of the total structural units constituting the polyvinyl ester or the PVA polymer.

As a preferable example of the PVA polymer (A), a vinyl alcohol unit does not contain or contains an &quot; acetalized vinyl alcohol unit &quot; corresponding to a structural unit acetalized with an aldehyde or a derivative thereof or the like, &Lt; / RTI &gt; The content of the acetalized vinyl alcohol unit in the PVA polymer (A) is preferably less than 10 mol%, more preferably less than 5 mol% based on the number of moles of all the structural units constituting the PVA polymer (A) , More preferably less than 3 mol%, and most preferably 0 mol%. In addition, in a PVA polymer containing an acetalized vinyl alcohol unit, usually two acetal structures are formed by reacting two vinyl alcohol units with one aldehyde or a derivative thereof. However, in the present specification, One such acetal structure is composed of two &quot; acetalized vinyl alcohol units &quot; (structural units), and the above &quot; content of acetalized vinyl alcohol units &quot; and &quot;Quot; and &quot; number of units &quot;.

The degree of saponification of the above-mentioned PVA polymer (A) which does not contain or contains the &quot; acetalized vinyl alcohol unit &quot; is low because the solubility in the adhesive, particularly, Is preferably 80 mol% or less, more preferably 65 mol% or less, further preferably 50 mol% or less, and more preferably 40 mol% or less, in view of solubility in these monomers in the case of containing monomers % Or less. If the degree of saponification of the PVA polymer (A) is too low, the adhesion between the PVA polymer-containing film and the protective film tends to be lowered. Therefore, the saponification degree of the PVA polymer (A) , More preferably 15 mol% or more, further preferably 20 mol% or more, and particularly preferably 25 mol% or more. The saponification degree of the PVA polymer (including the case of the PVA polymer (A)) in the present specification means the degree of saponification of the structural unit which can be converted into a vinyl alcohol unit by the saponification of the PVA polymer (typically a vinyl ester Refers to the ratio (mol%) of the number of moles of the vinyl alcohol unit to the total moles of the vinyl alcohol unit. The degree of saponification can be measured in accordance with the description of JIS K 6726-1994.

Another preferred example of the PVA polymer (A) is polyvinyl acetal containing an &quot; acetalized vinyl alcohol unit &quot; corresponding to a structural unit in which a vinyl alcohol unit is acetalized with an aldehyde or a derivative thereof. Examples of the aldehyde include formaldehyde, acetaldehyde, propionaldehyde, n-butylaldehyde, isobutylaldehyde, amylaldehyde, hexylaldehyde, heptylaldehyde, n-octylaldehyde, 2-ethylhexylaldehyde, cyclohexylaldehyde , Furfural, glyoxal, glutaraldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde, 4-methylbenzaldehyde, p-hydroxybenzaldehyde, m-hydroxybenzaldehyde, phenylacetaldehyde, . Examples of aldehyde derivatives include acetals (such as dialkyl acetals), vinyl esters, vinyl ethers, and vinyl halides, which can give corresponding aldehydes by hydrolysis. The acetalized vinyl alcohol unit contained in the polyvinyl acetal may be one or two or more kinds. Among polyvinyl acetals, those containing an acetalized vinyl alcohol unit corresponding to a structural unit in which the vinyl alcohol unit is acetalized with n-butylaldehyde or a derivative thereof (such as polyvinyl butyral ) Is preferable.

The content of the vinyl alcohol unit (-CH ₂ -CH (OH) -) in the total structural units constituting the polyvinyl acetal is preferably 5 mol% or more, more preferably 10 mol% or more , More preferably 20 mol% or more, further preferably 50 mol% or less, more preferably 40 mol% or less, still more preferably 30 mol% or less.

The content of the acetalized vinyl alcohol unit in the total structural units constituting the polyvinyl acetal can be, for example, 10 mol% or more. However, the adhesive strength and the solubility in an adhesive, particularly, Is preferably 40 mol% or more, more preferably 50 mol% or more, and more preferably 60 mol% or more from the viewpoints of solubility in these monomers in the case of containing a monomer such as a radical compound or a radical polymerizable compound , And preferably 90 mol% or less, more preferably 85 mol% or less, and further preferably 75 mol% or less.

The content of the vinyl ester units in the total structural units constituting the polyvinyl acetal is preferably 0.1 mol% or more, more preferably 0.3 mol% or more, still more preferably 0.5 mol% or more , More preferably 30 mol% or less, more preferably 20 mol% or less, still more preferably 10 mol% or less, particularly preferably 5 mol% or less. Examples of the vinyl ester unit include unvinylated vinyl ester units contained in the PVA polymer before acetalization used for producing polyvinyl acetal, and the like.

The degree of polymerization of the PVA polymer (A) is not particularly limited, but considering the viscosity of the resultant adhesive and the coating properties when the adhesive is coated on a protective film or the like, the degree of polymerization of the PVA polymer is preferably 2,000 or less More preferably 1,500 or less, further preferably 1,000 or less, and particularly preferably 500 or less. In consideration of the strength of the adhesive layer in the resulting adhesive, etc., it is preferably 100 or more, more preferably 150 or more, and even more preferably 200 or more. The polymerization degree of the PVA polymer (including the case of the PVA polymer (A)) referred to in the present specification means an average polymerization degree measured in accordance with the description of JIS K 6726-1994. In the case of polyvinyl acetal, since the degree of polymerization itself does not usually change before and after acetalization in the production thereof, the value of the degree of polymerization of the PVA polymer before acetalization, which is used for producing polyvinyl acetal, . &Lt; / RTI &gt;

The content of the PVA polymer (A) in the adhesive of the present invention is preferably 90% by mass or less, more preferably 50% by mass or less, from the viewpoints of the viscosity of the resultant adhesive and furthermore, , And more preferably 20 mass% or less. The content of the PVA polymer (A) in the adhesive of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, from the viewpoint of the strength of the adhesive layer in the resulting adhesive body , And still more preferably 3 mass% or more.

[Cationic polymerizable compound (B)]

As the cationically polymerizable compound (B), a compound having an oxetanyl group and / or oxylanyl group in the molecule can be preferably used. One kind of cationically polymerizable compound (B) may be used alone, or two or more kinds may be used in combination. The use of a polyfunctional compound as at least a part of the cationically polymerizable compound (B) is preferable because it can act as a crosslinking agent.

Examples of the compound having an oxetanyl group in the molecule include a compound having one oxetanyl group in the molecule and a compound having two or more oxetanyl groups in the molecule. Examples of the compound having an oxylanyl group in the molecule include an aliphatic compound having an oxylanyl group in the molecule and an alicyclic compound having an oxylanyl group in the molecule.

Specific examples of the compound having one oxetanyl group in the molecule include 3-ethyl-3-hydroxymethyloxetane, (3-ethyl-3-oxetanylmethoxy) methylbenzene, 4-fluoro- [ (3-ethyl-3-oxetanylmethoxy) methyl] benzene, 4-methoxy- [1- Ethyl-3-oxetanylmethoxy) ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3-oxetanylmethyl) phenyl ether, 3-oxetanylmethyl) ether, isobornyloxyethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyl Ethyl-3-oxetanylmethyl) ether, ethyldiethylene glycol (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, 2-tetrabromophenoxyethyl (3-ethyl- 3-oxetanylmethyl) ether, 2-tribromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, 2-hydroxyethyl 3-oxetanylmethyl) ether, 2-hydroxypropyl (3-ethyl-3-oxetanylmethyl) ether, butoxyethyl Ethyl-3-oxetanylmethyl) ether, pentabromophenyl (3-ethyl-3-oxetanylmethyl) ether and bornyl (3-ethyl-3-oxetanylmethyl) ether.

Examples of commercial products of compounds having one oxetanyl group in the molecule include OXT-101, OXT-211 and OXT-212 (manufactured by TOA Corporation).

Specific examples of the compound having two or more oxetanyl groups in the molecule include 3,7-bis (3-oxetanyl) -5-oxa- nonane, 3,3 '- (1,3- Bis (3-ethyl-3-oxetanylmethoxy) methyl] benzene, 1,2-bis [(3-ethyloxetane) (3-ethyl-3-oxetanylmethoxy) methyl] propane, ethylene glycol bis (3-ethyl-3-oxetanyl Ethyl-3-oxetanylmethyl) ether, tetraethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenylbis (3-ethyl-3-oxetanylmethyl) ether, tricyclodecanediyldimethylene (3-ethyl-3-oxetanylmethyl) ether, 1,4- (3-ethyl-3-oxetanylmethyl) ether, ethylene oxide (EO) modified bisphenol A (3-ethyl-3-oxetanylmethyl) ether, propylene oxide (PO) modified bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, EO modified hydrogenated bisphenol A bis 3-oxetanylmethyl) ether, PO-modified hydrogenated bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether and EO-modified bisphenol F .

Commercially available products having two or more oxetanyl groups in the molecule include OXT-121 and OXT-221 (manufactured by TOA Corporation).

Specific examples of the aliphatic compound having an oxiranyl group in the molecule include, for example, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether , Trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, glycerin triglycidyl ether, polypropylene glycol diglycidyl ether, aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin, one or two Polyglycidyl ethers of polyether polyols obtained by adding alkylene oxide of at least one kind, diglycidyl esters of aliphatic long chain dibasic acids, monoglycidyl ethers of aliphatic higher alcohols, glycidyl Epoxidized soybean oil, butyl epoxystearate, octyl stearate, epoxidized linseed oil, epoxidized polybutadiene, It may be a diene, etc.

Examples of commercially available aliphatic compounds having an oxyl group in the molecule include SR-NPG, SR-16H, SR-PG and SR-TPG (manufactured by Sakamoto Chemical Industry Co., Ltd.); PG-202 and PG- Manufactured by Hwaseong Co., Ltd.).

Specific examples of the alicyclic compound having an oxiranyl group in the molecule include 3 ', 4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5 (3,4-epoxy-6-methylcyclohexylmethyl) adipate, bis (3,4-epoxycyclohexylmethyl) adipate, bis , 3,4-epoxy-6-methylcyclohexyl-3 ', 4'-epoxy-6'-methylcyclohexanecarboxylate, epsilon -caprolactone-modified 3,4-epoxycyclohexylmethyl- -Epoxycyclohexanecarboxylate, trimethylcaprolactone-modified 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate,? -Methyl-? -Valerolactone-modified 3,4-epoxycyclo Epoxycyclohexanecarboxylate, methylenebis (3,4-epoxycyclohexane), di (3,4-epoxycyclohexylmethyl) ether of ethylene glycol, ethylene Switch and the like (3, 4-epoxycyclohexane carboxylate), epoxy hexahydrophthalic acid dioctyl cyclohexane, epoxy hexahydrophthalic acid di-2-ethylhexyl.

Examples of commercially available products of the alicyclic compounds having an oxiranyl group in the molecule include Celloxide 2021, Celloxide 2021P, Celloxide 2081, Celloxide 2083, Celloxide 2085, Polyd GT-300, Polyd GT-302, EPOLED GT-400, EPOLED 401, EPOLED 403 (manufactured by Daicel Co., Ltd.), and the like.

The content of the cationically polymerizable compound (B) in the adhesive of the present invention is not particularly limited, but is preferably 98% by mass or less, more preferably 95% by mass or less, from the viewpoint of the strength of the adhesive layer in the obtained adhesive body, More preferably 90% by mass or less, and particularly preferably 70% by mass or less. The content of the cationically polymerizable compound (B) in the adhesive of the present invention is preferably 10% by mass or more, more preferably 20% by mass or more from the viewpoints of the viscosity of the resultant adhesive and the coating property of the adhesive , And still more preferably 30 mass% or more.

[Cation polymerization initiator (C)]

As the cationic polymerization initiator (C), a compound capable of promoting the reaction between the PVA polymer (A) contained in the adhesive and the cationic polymerizable compound (B) by irradiation with an active energy ray can be used. Examples of the cationic polymerization initiator (C) include an onium salt-based initiator such as a sulfonium salt-based initiator and an iodonium salt-based initiator; a sulfonic acid derivative such as sulfonic acid derivatives, carboxylic acid esters, aryldiazonium salts, A quinolinium salt, an O-nitrobenzyl group-containing compound and the like, and an onium salt-based initiator is preferable, and a sulfonium salt-based initiator and an iodonium salt-based initiator are more preferable. These cationic polymerization initiators (C) may be used singly or in combination of two or more.

Examples of the sulfonium salt-based initiator include p-hydroxyphenylsulfone such as p-phenylbenzylmethylsulfonium salt, p-phenyldimethylsulfonium salt and benzylmethyl-p-hydroxyphenylsulfonium hexafluoroantimonate. Triarylsulfonium salts such as benzylmethylsulfonium salts, triphenylsulfonium salts and diphenyl [4- (phenylthio) phenyl] sulfonium salts, and the like, 4,4'-bis [di (? - hydroxyethoxy) phenylsulfonium ] Diphenylsulfide bishexafluoroantimonate, and other disulfonium salts having a bis [4- (diphenylsulfono) phenyl] sulfide skeleton.

Examples of the counteranion of the sulfonium salt in the sulfonium salt-based initiator include SbF ₆ ^- , AsF ₆ ^- , PF ₆ ^- , and BF ₄ ^- . Of these, SbF ₆ ^- , PF ₆ ^- are preferable.

Examples of the iodonium salt-based initiator include diphenyliodonium, bis (4-tert-butylphenyl) iodonium, (4-tert-butoxyphenyl) phenyliodonium, (4-methoxyphenyl) And iodonium salts such as iodonium.

As the cation polymerization initiator (C), a triarylsulfonium salt such as a diphenyl [4- (phenylthio) phenyl] sulfonium salt is particularly preferable from the viewpoint of thermal stability.

Examples of commercially available products of the cation polymerization initiator (C) include "CPI-100P" (manufactured by SANA PRO), "CPI-101A" (manufactured by SANA PRO), "IRGACURE 250" ADEKA OPTOMER SP-170 "(manufactured by ADEKA)," ADEKA OPTOMER SP-152 "(manufactured by ADEKA)," ADEKA OPTOMER SP-150 " (Trade name, manufactured by ADEKA), "SANEID SI-60L" (manufactured by SANSHIN CHEMICAL INDUSTRIES CO., LTD.), "SANEID SI-80L" -150 L &quot; (manufactured by Sanxin Chemical Industry Co., Ltd.).

The content of the cationic polymerization initiator (C) in the adhesive of the present invention is not particularly limited. However, the content of the cationic polymerization initiator (C) in the adhesive of the present invention can be suitably selected for the film containing the PVA polymer by an acid derived from the cationic polymerization initiator It is preferably 10 mass% or less, more preferably 5 mass% or less, still more preferably 3 mass% or less. In consideration of the curing speed of the adhesive and the adhesive force after curing, the content of the cation polymerization initiator (C) in the adhesive of the present invention is preferably 0.01 mass% or more, more preferably 0.05 mass% or more, And more preferably 0.1 mass% or more.

It is preferable that the adhesive of the present invention further comprises a radical polymerizable compound (D) and a radical polymerization initiator (E). The cationic polymerization initiator (C) and the radical polymerization initiator (E) contained in the adhesive are excited and the reaction between the cationic polymerizable compound (B) and the radical polymerizable compound (D ), And so on. In this process, the PVA polymer (A) can be cured together with the cationic polymerizable compound (B), the radical polymerizable compound (D) and a polymer thereof, and an adhesive layer can be formed. At least a part of the cationically polymerizable compound (B) may be a compound (BD) which is cationically polymerizable as well as a radical polymerizable compound. In the case where at least a part of the cationically polymerizable compound (B) is a compound (BD) which is also a radical polymerizable compound in addition to cationically polymerizable properties, it is preferable to further include a radical polymerization initiator (E).

Since the adhesive of the present invention contains the cationic polymerizable compound (B), the adhesive property to the film containing the PVA polymer is excellent. Further, when the adhesive of the present invention further contains the radical polymerizable compound (D), the adhesion to the protective film is further improved. As the adhesive of the present invention, the PVA polymer (A), the cationic polymerizable compound (B), the cationic polymerization initiator (C), the cationic polymerization initiator ), A radical polymerizing compound (D) and a radical polymerization initiator (E), an adhesive containing a PVA polymer (A), a radical polymerizable compound (BD) (C) and a radical polymerization initiator (E).

[Radical Polymerizable Compound (D)]

As the radically polymerizable compound (D), a compound having a (meth) acryloyl group in the molecule can be preferably used. The radically polymerizable compound (D) may be used singly or in combination of two or more kinds. Further, it is preferable to use a polyfunctional compound as at least a part of the radically polymerizable compound (D) because it can act as a crosslinking agent.

Specific examples of the compound having a (meth) acryloyl group in the molecule include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) (Meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isobutyl (meth) acrylate, (Meth) acrylate, isodecyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl Stearyl (meth) acrylate, isostearyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, boron (meth) acrylate, tricyclodecanyl , Dicyclopentanyl (meth) acrylate, dicyclopentyl (meth) acrylate 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, 2- (Meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, (Meth) acrylate, methoxyethyleneglycol, (meth) acrylate, ethoxyethyl (meth) acrylate, polyethylene glycol monoester of (meth) acrylate, polypropylene glycol monoester of Methoxypolyethylene glycol, (meth) acrylic acid methoxypolypropylene glycol, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 7-amino-3,7-dimethyloctyl Acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di Acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, tetraethylene glycol di (Meth) acrylic acid adducts of di (meth) acrylate, tripropylene glycol di (meth) acrylate, bisphenol A diglycidyl ether, pentaerythritol tri (meth) acrylate, pentaerythritol tetra ) Acrylate, polyester di (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2- (2,3-dihydroxypropyl) (Meth) acrylate, tricyclodecane dimethanol (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, tricyclodecane dimethanol Di (meth) acrylates of diols which are ethylene oxide or propylene oxide adducts of bisphenol A, di (meth) acrylates of diols additionally of ethylene oxide or propylene oxide of hydrogenated bisphenol A, di (meth) (Meth) acrylate in which (meth) acrylate is added to the diglycidyl ether of A, and the like.

Other examples of the radical polymerizable compound (D) include epoxy (meth) acrylates such as bisphenol A type epoxy acrylate resin, phenol novolak type epoxy acrylate resin and cresol novolak type epoxy acrylate resin, (Meth) acrylate-based resin obtained by reacting a urethane resin obtained from a polyol and an organic isocyanate with a hydroxyl group-containing (meth) acrylate ester, and a urethane (meth) (Meth) acryloyl group-containing compounds such as a polyester (meth) acrylate-series resin and an N-hydroxyethyl (meth) acrylamide.

The content of the radically polymerizable compound (D) in the adhesive of the present invention is not particularly limited, but is preferably 98% by mass or less, more preferably 95% by mass or less from the viewpoint of the strength of the adhesive layer in the obtained adhesive body More preferably 90% by mass or less, and particularly preferably 70% by mass or less. The content of the radical polymerizable compound (D) in the adhesive of the present invention is preferably 10% by mass or more, more preferably 20% by mass or more from the viewpoints of the viscosity of the resulting adhesive and the coating property of the adhesive And more preferably 30 mass% or more.

[Radical polymerization initiator (E)]

As the radical polymerization initiator (E), a compound capable of promoting the reaction of the radically polymerizable compound (D) contained in the adhesive by irradiation of an active energy ray can be used. Examples of such a radical polymerization initiator (E) include carbonyl compounds such as acetophenones, benzophenones, Michler's ketones, and benzoins; sulfur compounds such as tetramethylthiuram monosulfide and thiosanthone; And a carbonyl compound is preferable. These radical polymerization initiators (E) may be used singly or in combination of two or more.

The acetophenones include, for example, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2- Phenylpropan-1-one, and the like.

Examples of the benzophenones include benzophenone, benzoylbenzoic acid, hydroxybenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, and acrylated benzophenone.

Examples of the benzoin include benzoin, benzoin methyl ether, benzoin isopropyl ether, and the like.

As the radical polymerization initiator (E), acetophenones or benzophenones are more preferable in view of reactivity, transparency and the like, and 1-hydroxycyclohexyl phenyl ketone is more preferable.

Examples of commercially available products of the radical polymerization initiator (E) include commercially available products such as "IRGACURE 184" (1-hydroxycyclohexyl phenyl ketone; BASF), "Solvastron BIPE" (Kurogane Chemical Co., DAROCUR 1173 &quot; (2-hydroxy-2-methyl-thiophene-1-one, manufactured by BASF) (Manufactured by BASF), IRGACURE 295 (manufactured by BASF), IRGACURE 127 (manufactured by BASF), IRGACURE 907 (manufactured by BASF), IRGACURE 369 , IRGACURE 819 (manufactured by BASF), IRGACURE 819DW (manufactured by BASF), IRGACURE 784 (manufactured by BASF), KAYACURE BP (manufactured by Nippon Yakushinkai), IRGACURE 379 (IRGACURE OXE 01 manufactured by BASF), IRGACURE OXE 02 (manufactured by BASF), IRGACURE 754 (manufactured by BASF), IRGACURE 500 (manufactured by BASF), IRGACURE 1800 , &Quot; IRGACURE 1870 &quot; (manufactured by BASF), &quot; DARO Quot; CUR 4265 &quot; (manufactured by BASF), &quot; KAYACURE DETX-S &quot; (manufactured by Nippon Yakushin), &quot; ESACURE KIP 150 &quot; ) And the like.

The content of the radical polymerization initiator (E) in the adhesive of the present invention is not particularly limited. However, from the viewpoint of preventing the lowering of the molecular weight of the cured product and the deterioration of the heat resistance due to the excessive increase in the curing rate, More preferably 10 mass% or less, further preferably 5 mass% or less, and still more preferably 3 mass% or less. The content of the radical polymerization initiator (E) in the adhesive of the present invention is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and more preferably 0.1% by mass or more, in view of the curing rate of the adhesive, More preferably, it is at least% by mass.

[Compound (BD) which is cationically polymerizable as well as radically polymerizable]

As described above, the cationically polymerizable compound (B) may be a radically polymerizable compound (BD) in addition to being cationically polymerizable as at least a part thereof. (BD) in addition to the cationically polymerizable compound (BD) in addition to the cationically polymerizable compound (BD), the PVA polymer (A) and the cationically polymerizable compound The crosslinking reaction with the compound (B), the radical polymerizable compound (D) and the like proceeds, and the strength of the adhesive layer in the obtained adhesive body is further improved. As a result, the film containing the PVA polymer and the protective film The adhesive strength is further improved. As the compound (BD) which is radical polymerizable in addition to the cationically polymerizable compound, a compound having an oxetanyl group and / or oxylanyl group in the molecule and further having a (meth) acryloyl group can be preferably used . The compound (BD) which is cationically polymerizable as well as a radical polymerizable compound may be used singly or in combination of two or more.

Specific examples of the compound which is cationically polymerizable as well as radical polymerizable (BD) include alicyclic epoxy group-containing (meth) acrylates such as 3,4-epoxycyclohexylmethyl (meth) acrylate, (Meth) acrylates such as (meth) acrylate and (meth) acrylate; oxetanyl group-containing (meth) acrylates such as 3-ethyl-3- (meth) acryloyloxymethyloxetane .

The content of the radically polymerizable compound (BD) in addition to the cationically polymerizable property in the adhesive of the present invention is not particularly limited. However, from the viewpoint of the strength of the adhesive layer in the obtained adhesive body, the content is preferably 90% More preferably 85% by mass or less, further preferably 80% by mass or less, particularly preferably 60% by mass or less. From the viewpoints of the viscosity of the resultant adhesive and furthermore, the coating property of the adhesive, the content of the compound (BD) which is cationically polymerizable as well as radically polymerizable in the adhesive of the present invention is preferably 5% by mass or more By mass, more preferably 10% by mass or more, and still more preferably 15% by mass or more.

[Other optional components]

The adhesive may be prepared by mixing the PVA polymer (A), the cationic polymerizable compound (B), the cationic polymerization initiator (C), the radical polymerizable compound (D) and the radical polymerization initiator (E) (B) contains a compound other than the cationically polymerizable compound (BD), which is also a radically polymerizable compound). Examples of the other components include a crosslinking agent, a sensitizer, a diluent, a tackifier, a softener, a filler, a stabilizer, a pigment, and a dye. The other component may be an organic compound or an inorganic compound.

(Crosslinking agent)

The crosslinking agent crosslinks the PVA polymer (A), the cationic polymerizable compound (B), the radically polymerizable compound (D) and the like, and the strength of the adhesive layer in the adhesive agent thus obtained is further improved, As a result, the adhesion between the protective film and the film containing the PVA polymer is further improved. The crosslinking agent may be used alone or in combination of two or more.

Examples of the crosslinking agent include nitrogen compounds such as polyoxazoline, isocyanate compounds such as diphenylmethane diisocyanate, aldehyde compounds such as glutaraldehyde, zirconium compounds such as zirconium ammonium carbonate, titanium compounds such as titanium lactate And the like.

The content of the crosslinking agent in the adhesive of the present invention is not particularly limited, but from the viewpoints of the viscosity of the resultant adhesive, and the coating property of the adhesive, the content of the crosslinking agent is preferably 20% by mass or less, more preferably 15% More preferable. The content of the crosslinking agent may be 1% by mass or more, for example.

(Sensitizer)

The sensitizer accelerates the curing of the adhesive by moving or broadening the sensitivity of the active energy ray. Examples of such sensitizers include n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthioic acid, triethylamine and the like, with triethylamine being preferred.

The sensitizer is preferably used in combination with the cationic polymerization initiator (C) or the radical polymerization initiator (E). The mass ratio of the sensitizer to the sum of the cation polymerization initiator (C) and the radical polymerization initiator (E) and the sensitizer is preferably 5% by mass or more, more preferably 10% by mass or more, Do. The upper limit of the mass ratio of the sensitizer is not particularly limited, but may be 90% by mass or less, for example.

(diluent)

The diluent is used to adjust the viscosity of the adhesive and the mechanical strength after curing the adhesive. Examples of the diluent include compounds having no active energy ray-curable group, and specific examples thereof include phthalic acid esters, non-aromatic dibasic acid esters, aliphatic esters, esters of polyalkylene glycols, phosphoric acid esters, Polyester plasticizers obtained from melted esters, chlorinated paraffins, hydrocarbon oils, process oils, polyethers, dibasic acids and dihydric alcohols, and vinyl polymers obtained by polymerizing vinyl monomers. These inert compounds may be used singly or in combination of two or more. Further, the diluent may have a functional group (hydroxyl group, carboxyl group, halogen group, etc.) other than the active energy ray-curable group.

Examples of the phthalic acid esters include dibutyl phthalate, diheptyl phthalate, di (2-ethylhexyl) phthalate, and butyl benzyl phthalate.

Examples of the non-aromatic dibasic acid esters include dioctyl adipate, dioctyl sebacate, dibutyl sebacate, isodecyl succinate, and the like.

Examples of the aliphatic ester include butyl oleate and methyl acetyl ricinoleate.

Examples of the esters of the polyalkylene glycols include diethylene glycol dibenzoate, triethylene glycol dibenzoate, and pentaerythritol ester.

Examples of the phosphate ester include tricresyl phosphate, tributyl phosphate, and the like.

Examples of the hydrocarbon-based oil include alkyldiphenyl, partially hydrogenated terphenyl, and the like.

Examples of the polyethers include polyether polyols; and derivatives obtained by converting a hydroxyl group of a polyether polyol into an ester group or an ether group. Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

Examples of the dibasic acid include sebacic acid, adipic acid, azelaic acid, and phthalic acid. Examples of the dihydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol and the like.

Examples of the vinyl polymer include (meth) acrylic polymers, polybutene, polyisobutylene, styrene polymers such as polystyrene and poly-α-methylstyrene, diene polymers such as polybutadiene and polychloroprene ), Vinyl ether polymers, copolymers thereof (butadiene-acrylonitrile copolymers and the like), and the like.

The number average molecular weight (Mn) of the diluent is preferably 15,000 or less, more preferably 10,000 or less, still more preferably 8,000 or less, further preferably 400 or more, more preferably 800 or more, Do. When the number average molecular weight (Mn) of the diluent is equal to or less than the upper limit, the viscosity of the resulting adhesive can be adjusted to an appropriate range, and handling properties of the adhesive are improved. Also, since the number average molecular weight (Mn) of the diluent is equal to or lower than the lower limit described above, the diluent can be prevented from flowing out over time from the cured product after curing the adhesive, and the initial properties can be maintained for a long period of time.

The molecular weight distribution (Mw / Mn) when the diluent is a polymer is not particularly limited, but is usually less than 1.8, more preferably 1.7 or less, more preferably 1.5 or less, still more preferably 1.3 or less.

The content of the diluting agent in the adhesive of the present invention is not particularly limited, but is preferably 70% by mass or less, more preferably 50% by mass or less, and more preferably 30% by mass or less in view of the strength of the adhesive layer in the obtained adhesive body. Or less, more preferably 10 mass% or less.

(Tackifier)

The tackifier imparts tackiness to the cured product after curing the adhesive. Examples of the tackifier include a chroman-indene resin, a phenol resin, a pt-butylphenol-acetylene resin, a phenol-formaldehyde resin, a terpene resin, a synthetic terpene resin, an aromatic modified terpene resin, a xylene formaldehyde resin , An aromatic hydrocarbon resin, an aliphatic cyclic hydrocarbon resin, an oligomer of a monoolefin or a diolefin, a hydrocarbon resin, a hydrogenated hydrocarbon resin, a polybutene, a polyhydric alcohol ester of rosin, a hydrogenated rosin, a hydrogenated rosin, Esters with alcohols or polyhydric alcohols, and terpene resins. Among them, preferred are terpene resins, synthetic terpene resins, aromatic modified terpene resins, aliphatic saturated petroleum resins, rosin esters, disproportionated rosin esters, hydrogenated rosin esters, aliphatic petroleum resins (C5 aliphatic petroleum resins, Aliphatic petroleum resin, etc.), or a modified aliphatic petroleum resin.

[Method of producing adhesive]

The method for producing the adhesive of the present invention is not particularly limited, and examples thereof include a PVA polymer (A), a cationic polymerizable compound (B), a cationic polymerization initiator (C) The compound (D), the radical polymerization initiator (E) and other components (the case where the cationic polymerizable compound (B) is a compound which is also a radical polymerizable compound (BD) Can be easily produced by mixing and stirring one kind or two or more kinds of optional components.

[Film containing PVA polymer]

The adhesive of the present invention is for adhering a protective film to a film comprising a PVA polymer (the term "PVA polymer film-containing film" may be abbreviated as "PVA polymer film" in some cases). Examples of the PVA polymer contained in the PVA polymer film include vinyl acetate, vinyl formate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl versatate, vinyl laurate, vinyl stearate, vinyl benzoate, isopropenyl acetate Of the polyvinyl ester obtained by polymerizing one or more vinyl esters of the above-mentioned polyesters. Of the above vinyl esters, compounds having a vinyloxycarbonyl group (H ₂ C = CH-O-CO-) in the molecule are preferable from the viewpoints of ease of production of PVA polymer, Is more preferable.

The above-mentioned polyvinyl ester is preferably obtained by using only one kind of vinyl ester or two or more kinds of vinyl esters as monomers, more preferably obtained by using only one kind of vinyl ester as a monomer, It may be a copolymer of one or more vinyl esters and other monomers copolymerizable therewith.

Examples of the other monomer copolymerizable with the vinyl ester include (meth) acrylic acid or a salt thereof, (meth) acrylate such as methyl (meth) acrylate, Propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t- (Meth) acrylate, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, (Meth) acrylamide propylsulfonic acid or its salt, (meth) acrylamidopropyldimethylamine or its salt, N, N-dimethyl (meth) acrylamide, diacetone (Meth) acrylamide derivatives such as acrylamide or derivatives thereof; Propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, N-vinyl pyrrolidone, Vinyl ethers such as butyl vinyl ether, t-butyl vinyl ether, dodecyl vinyl ether and stearyl vinyl ether, vinyl cyanide such as (meth) acrylonitrile, vinyl chloride, vinylidene chloride, vinyl fluoride and vinylidene fluoride Allyl compounds such as allyl acetate and allyl chloride, maleic acid or its salts, esters or acid anhydrides, itaconic acid or its salts, esters or acid anhydrides, vinylsilyl compounds such as vinyltrimethoxysilane, Salts and the like. The above-mentioned polyvinyl esters may have a structural unit derived from one or more of the above-mentioned other monomers.

The proportion of the structural unit derived from the other monomer in the polyvinyl ester is preferably 15 mol% or less, more preferably 10 mol% or less, based on the number of moles of the total structural units constituting the polyvinyl ester , And still more preferably 5 mol% or less.

As the PVA polymer, those not graft-copolymerized can be preferably used. However, if the PVA polymer is within a range that does not significantly impair the effect of the present invention, the PVA polymer may be modified with one or more graft copolymerizable monomers . The graft copolymerization can be carried out on at least one of a polyvinyl ester and a PVA polymer obtained by saponifying it. Examples of the graft copolymerizable monomer include an unsaturated carboxylic acid or a derivative thereof, an unsaturated sulfonic acid or a derivative thereof, and an -olefin having 2 to 30 carbon atoms. The proportion of the structural unit derived from the graft copolymerizable monomer in the polyvinyl ester or the PVA polymer is preferably 5 mol% or less based on the number of moles of the total structural units constituting the polyvinyl ester or the PVA polymer.

A part of the hydroxyl group of the PVA polymer may be crosslinked or may not be crosslinked. In the above-mentioned PVA polymer, a part of the hydroxyl groups may react with an aldehyde compound such as acetaldehyde, butylaldehyde or the like to form an acetal structure, or may not react with these compounds and form an acetal structure.

The degree of polymerization of the PVA polymer is not particularly limited, but is preferably 1,000 or more. When the degree of polymerization of the PVA polymer is 1,000 or more, the polarizing performance of the resulting polarizing film can be further improved. If the degree of polymerization of the PVA polymer is too high, the production cost of the PVA polymer tends to increase and the processability at the time of film formation (film formation) tends to be poor. Therefore, the degree of polymerization of the PVA polymer is preferably in the range of 1,000 to 10,000 More preferably within the range of 1,500 to 8,000, and particularly preferably within the range of 2,000 to 5,000.

The saponification degree of the PVA polymer is preferably 95 mol% or more, more preferably 98 mol% or more, still more preferably 99 mol% or more, and 99.3 mol% or more, in view of improving the heat and humidity resistance of the resulting polarizing film % Or more.

The PVA polymer film may contain a plasticizer together with the above-mentioned PVA polymer. By including the plasticizer in the PVA polymer film, the handleability and the stretchability of the PVA polymer film can be improved. As the plasticizer, a polyhydric alcohol is preferably used. Specific examples of the plasticizer include ethylene glycol, glycerin, propylene glycol, diethylene glycol, diglycerin, triethylene glycol, tetraethylene glycol, trimethylolpropane, The film may comprise one or more of these plasticizers. Of these, glycerin is preferable in that the stretchability of the PVA polymer film becomes better.

The content of the plasticizer in the PVA polymer film is preferably 2 to 20 parts by mass, more preferably 3 to 17 parts by mass, and further preferably 4 to 14 parts by mass with respect to 100 parts by mass of the PVA polymer. The content of the plasticizer in the PVA polymer film is 2 parts by mass or more based on 100 parts by mass of the PVA polymer, thereby improving the stretchability of the PVA polymer film. On the other hand, when the content of the plasticizer in the PVA polymer film is 20 parts by mass or less based on 100 parts by mass of the PVA polymer, the plasticizer bleeds out on the surface of the PVA polymer film to lower the handling property of the PVA polymer film Can be suppressed.

When a PVA polymer film is produced using a stock solution for forming a PVA polymer film to be described later, the film forming property is improved to suppress the occurrence of thickness irregularity of the film, and a metal roll or a belt When used, since the PVA polymer film from these metal rolls or belts can be easily peeled, it is preferable to incorporate a surfactant into the raw film-forming solution. When a PVA polymer film is produced from a film-forming solution containing a surfactant, the PVA polymer film may contain a surfactant. The kind of the surfactant contained in the surfactant to be added to the solution for forming the PVA polymer film and further contained in the PVA polymer film is not particularly limited, but from the viewpoint of the separability from the metal roll or the belt, Or nonionic surfactants are preferable, and nonionic surfactants are particularly preferable.

As the anionic surfactant, for example, a carboxylic acid type such as potassium laurate, a sulfuric acid ester type such as octylsulfate and a sulfonic acid type such as dodecylbenzenesulfonate are suitable.

Examples of the nonionic surfactant include alkyl ether types such as polyoxyethylene oleyl ether and the like, alkylphenyl ether types such as polyoxyethylene octylphenyl ether and the like, alkyl ester types such as polyoxyethylene laurate, Alkyl amines such as ethylene lauryl amino ether, alkyl amide types such as polyoxyethylene lauryl amide, polypropylene glycol ether types such as polyoxyethylene polyoxypropylene ether, diethanol amide laurate, diethanol amide oleic acid and the like And the allylphenyl ether type such as polyoxyalkylene allylphenyl ether, and the like are suitable.

These surfactants may be used singly or in combination of two or more kinds.

When the surfactant is mixed into the stock solution for forming a PVA polymer film, the content of the surfactant in the stock solution of the film-forming composition, and further the content of the surfactant in the PVA polymer film, It is preferably in the range of 0.01 to 0.5 parts by mass, more preferably 0.02 to 0.3 parts by mass with respect to 100 parts by mass of the PVA polymer contained. The content of the surfactant is 0.01 part by mass or more based on 100 parts by mass of the PVA polymer, whereby the film formability and the peelability can be improved. On the other hand, when the content of the surfactant is 0.5 parts by mass or less based on 100 parts by mass of the PVA polymer, the surfactant bleeds out on the surface of the PVA polymer film to prevent blocking due to deterioration in handling properties.

The PVA polymer film may be only a PVA polymer or may be only a PVA polymer and the above plasticizer and / or a surfactant. If necessary, an antioxidant, a cryoprotectant, a pH adjuster, a masking agent, And other components other than the above-mentioned PVA polymer, plasticizer and surfactant such as an oil agent.

The content of the PVA polymer in the PVA polymer film is preferably in the range of 50 to 100 mass%, more preferably in the range of 80 to 100 mass%, more preferably in the range of 85 to 100 mass% desirable.

The thickness of the PVA polymer film is not particularly limited, but is preferably 60 占 퐉 or less, more preferably 50 占 퐉 or less, and even more preferably 30 占 퐉 or less. On the other hand, from the viewpoint that the polarizing film can be produced more smoothly, the thickness is preferably 1 占 퐉 or more, more preferably 3 占 퐉 or more.

The shape of the PVA polymer film is not particularly limited, but a long film is preferable in that the polarizing film can be continuously produced with good productivity. The length of the elongate film is not particularly limited and may be suitably set according to the intended use of the polarizing film to be produced. For example, the length may be in the range of 5 to 20,000 m. The width of the long film is not particularly limited and may be 50 cm or more, for example. However, since a polarizing film having a wide width is recently required, it is preferably 1 m or more, more preferably 2 m or more, m or more. There is no particular limitation on the upper limit of the width of the elongate film. However, if the width is too wide, there is a tendency that uniform elongation becomes difficult when a polarizing film is produced by a practical apparatus. The width of the film is preferably 7 m or less.

The form of the PVA polymer film is not particularly limited and may be either a single layer form or a laminate form such as a PVA polymer film formed on a thermoplastic resin film by a coating method or the like, (Coat or the like) work, the cost of the thermoplastic resin film, and the like.

The production method of the PVA polymer film is not particularly limited and a production method in which the thickness and width of the film after film formation are more uniform can be preferably employed. For example, the PVA polymer constituting the PVA polymer film , And if necessary, one or more of a plasticizer, a surfactant and other components dissolved in a liquid medium, a PVA polymer and, if necessary, further plasticizers, surfactants, other components and liquids And a medium containing one or more of the above-mentioned solvents, and the PVA polymer is melted. When the stock solution for film formation contains at least one of a plasticizer, a surfactant and other components, it is preferable that the components are uniformly mixed.

Examples of the liquid medium used for the preparation of the film-forming solution include water, dimethylsulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, ethylene glycol, glycerin, propylene glycol, diethylene glycol, Triethylene glycol, tetraethylene glycol, trimethylolpropane, ethylenediamine, diethylenetriamine and the like, and one or more of these may be used. Among them, water is preferable from the viewpoint of a small load on the environment and in view of recoverability.

The volatile matter content of the stock film-forming solution (the content ratio of the volatile component such as a liquid medium removed by volatilization or evaporation at the time of film-forming in the stock film-forming solution) varies depending on the film-forming method, More preferably in the range of 55 to 90% by mass, and still more preferably in the range of 60 to 85% by mass. When the volatile fraction of the film-forming raw liquid is 50 mass% or more, the viscosity of the film-forming raw liquid does not become too high, filtration and defoaming at the time of preparation of the film-forming liquid are smoothly carried out, and production of a PVA polymer film with few foreign matters or defects is facilitated . On the other hand, when the volatile fraction of the undiluted film forming solution is 95 mass% or less, the concentration of the undiluted film-forming solution does not become too low, and the production of an industrial PVA polymer film becomes easy.

Examples of the film forming method for forming the PVA polymer film using the above-mentioned film forming stock solution include a cast film forming method, an extrusion film forming method, a wet film forming method and a gel film forming method, Extrusion film forming method is preferable. These film-forming methods may be used alone or in combination of two or more. Among these film forming methods, a cast film forming method and an extrusion film forming method are more preferable because a PVA polymer film having uniform thickness and width and good physical properties can be obtained. The PVA polymer film can be subjected to drying or heat treatment, if necessary.

Examples of a specific method for producing a PVA polymer film include a method of producing a PVA polymer film by using a T-shaped slit die, a hopper plate, an I-die, a lip coater die, And the volatile component is evaporated from one surface of the discharged or softened film on the circumferential surface of the first roll (or belt) by uniformly discharging or casting it on the circumferential surface of the first roll (or belt) Dried on the circumferential surface of one or a plurality of heated and rotated rolls disposed on the downstream side thereof, or further dried by passing through a hot-air drying apparatus, It is industrially preferable to employ a method of taking the solution. The drying by the heated roll and the drying by the hot air drying apparatus may be carried out in appropriate combination.

By the above-described production method, a PVA polymer film which is not substantially stretched (not subjected to stretching treatment) can be easily obtained. The PVA polymer film can be directly adhered to the protective film using the adhesive of the present invention. In the present invention, the PVA polymer film to be adhered to the protective film is preferably a stretched film, And an optical film such as a retardation film.

[Production method of polarizing film]

The method for producing the polarizing film using the substantially unstretched PVA polymer film as a raw material film is not particularly limited and any conventionally employed method may be employed, The polarizing film can be produced by subjecting the PVA polymer film to a swelling treatment, a dyeing treatment, a stretching treatment and, if necessary, a crosslinking treatment, a fixing treatment, a drying treatment, a heat treatment, and the like. In this case, the order of each treatment such as swelling treatment, dyeing treatment, stretching treatment and fixing treatment is not particularly limited, and one or two or more treatments may be simultaneously carried out. In addition, one or two or more of the treatments may be performed twice or more.

The swelling treatment can be carried out by immersing the PVA polymer film in water (in water). The temperature of the water at the time of immersion in water is preferably in the range of 20 to 40 캜, more preferably in the range of 22 to 38 캜, still more preferably in the range of 25 to 35 캜. The time for immersion in water is preferably within a range of, for example, 0.1 to 5 minutes, and more preferably within a range of 0.5 to 3 minutes. Further, the water at the time of immersion in water is not limited to pure water, and may be an aqueous solution in which various components are dissolved, or a mixture of water and an aqueous medium.

The dyeing treatment is preferably carried out using an iodine dye, and the dyeing step may be any of the steps before the stretching treatment, during the stretching treatment, and after the stretching treatment. The dyeing is generally carried out by immersing the PVA polymer film in a solution (particularly an aqueous solution) containing iodine-iodide as a dyeing bath, and such a dyeing method is suitably employed also in the present invention. The concentration of iodine in the dyeing bath is preferably in the range of 0.01 to 0.5 mass%, and the concentration of potassium iodide is preferably in the range of 0.01 to 10 mass%. The temperature of the dyeing bath is preferably 20 to 50 캜, particularly 25 to 40 캜.

The crosslinking treatment can be carried out by immersing the PVA polymer film in an aqueous solution containing a crosslinking agent. When the crosslinking treatment is carried out, crosslinking is introduced into the PVA polymer film, and elution of the PVA polymer into water can be effectively prevented when the stretching treatment is carried out at a relatively high temperature and in a wet manner. From such viewpoints and the like, the crosslinking treatment is preferably carried out after the dyeing treatment. As the crosslinking agent, boron compounds such as boric acid salts such as boric acid and borax can be used. The concentration of the crosslinking agent in the aqueous solution containing the crosslinking agent is preferably within a range of 1 to 15 mass%, more preferably within a range of 2 to 7 mass%. The aqueous solution containing the crosslinking agent may contain an auxiliary agent such as potassium iodide. The temperature of the aqueous solution containing the crosslinking agent is preferably in the range of 20 to 50 캜, and more preferably in the range of 25 to 40 캜.

The stretching treatment may be performed by either a wet stretching method or a dry stretching method. In the case of the wet stretching method, it may be carried out in an aqueous solution containing boric acid, or in a fixed treatment bath as described above or in a dyeing bath described below. In the case of the dry stretching method, the PVA polymer film after the absorption can be used in air. Among them, the wet drawing method is preferable, and the uniaxial drawing is more preferable in an aqueous solution containing boric acid. The concentration of boric acid in the aqueous solution of boric acid is preferably within a range of 0.5 to 6.0 mass%, more preferably within a range of 1.0 to 5.0 mass%, and particularly preferably within a range of 1.5 to 4.0 mass%. The boric acid aqueous solution may contain potassium iodide, and the concentration thereof is preferably within a range of 0.01 to 10 mass%.

The stretching temperature in the stretching treatment is preferably in the range of 30 to 90 占 폚, more preferably in the range of 40 to 80 占 폚, and particularly preferably in the range of 50 to 70 占 폚.

The stretching magnification in the stretching treatment is preferably 5 times or more, more preferably 5.5 times or more, and particularly preferably 6 times or more, in view of the polarizing performance of the resulting polarizing film. The upper limit of the draw ratio is not particularly limited, but the draw ratio is preferably 8 times or less.

In the production of the polarizing film, it is preferable to perform fixing treatment to strengthen the adsorption of the dye (iodine, etc.) to the PVA polymer film. As the fixed treatment bath used for the fixing treatment, an aqueous solution containing one kind or two or more kinds of boron compounds such as boric acid and borax can be used. If necessary, an iodine compound or a metal compound may be added to the fixed treatment bath. The concentration of the boron compound in the fixed treatment bath is generally preferably about 2 to 15 mass%, particularly about 3 to 10 mass%. The temperature of the fixed treatment bath is preferably 15 to 60 ° C, particularly 25 to 40 ° C.

The drying treatment is preferably carried out at 30 to 150 ° C, more preferably 50 to 130 ° C. By drying at a temperature within the above range, a polarizing film excellent in dimensional stability is likely to be obtained.

[Other PVA polymer films]

As the PVA polymer film other than the polarizing film and the retardation film described above, for example, an optical film other than the polarizing film and the retardation film, a conductive film, A cover film, a transfer film, an abrasive film, a wind film, a decorative film, an adhesive film, a vibration-damping film, a biodegradable film and an antibacterial film. Examples of the optical film other than the polarizing film and the retardation film include an antireflection film, an orientation film, a polarizing layer protective film, a viewing angle improving film, a brightness enhancement film, an electromagnetic wave shielding film, a light shielding film, , A lens filter, an optical low-pass filter (OLPF) film, a weather-resistant film, and the like.

[Protection film]

The protective film to be adhered to the PVA polymer film using the adhesive of the present invention is not particularly limited, and examples thereof include an ionomer, polyethylene, cellulose, triacetyl cellulose (TAC), (meth) acrylic polymer, Polymer, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polypropylene, polyester, polycarbonate, polystyrene, polyacrylonitrile, ethylene vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methacrylic acid copolymer , Nylon, and the like. Of these, in view of being able to function as a good protective film when a polarizing film or a retardation film is used as the PVA polymer film, a film containing triacetyl cellulose, a film containing a (meth) acrylic polymer, Or a film containing an alicyclic structure-containing polymer is preferable. The content of the polymer in the film is preferably 50 mass% or more, more preferably 80 mass% or more, and further preferably 85 mass% or more.

In order to further improve the adhesion between the protective film and the adhesive layer, the surface of the protective film may be modified by known corona treatment, plasma treatment, UV treatment, flame treatment or the like, if necessary.

The thickness of the protective film is not particularly limited, but is preferably 200 占 퐉 or less, more preferably 100 占 퐉 or less. On the other hand, the thickness is preferably 5 占 퐉 or more, and more preferably 10 占 퐉 or more, from the viewpoint of improving the mechanical strength of the adhesive agent to be obtained.

[Use of adhesive]

Examples of the use of the adhesive of the present invention include the use of a polarizing film or a retardation film to adhere the protective film to the polarizing film or the retardation film as described above (production of a polarizing plate or a retardation plate); a synthetic resin, Etc., and the use of a PVA polymer film, and is particularly useful in the production of a polarizing plate or a retardation plate, and in particular, in the production of a polarizing plate.

The adhesive of the present invention exhibits a high adhesive force in adhesion between the PVA polymer film and the protective film. The adhesive force between the PVA polymer film and the protective film after curing of the adhesive is preferably 6.0 N / 25 mm or more, more preferably 6.5 N / 25 mm or more, and still more preferably 7.0 N / 25 mm or more. The peeling force can be obtained by the method described later in the examples.

<Adhesive body>

Next, an embodiment of the adhesive agent of the present invention will be described. The adhesive agent 1 of Fig. 1 comprises a PVA polymer film 2, a protective film 4, an adhesive layer 3 disposed between the PVA polymer film 2 and the protective film 4, Respectively. Here, the adhesive layer 3 is formed from the adhesive of the present invention.

[Adhesive layer]

The adhesive layer 3 is formed from the adhesive. Specifically, it can be formed by irradiating the adhesive with an active energy ray. The adhesive layer (3) may contain an additive depending on the use of the adhesive body (1).

Although the thickness of the adhesive layer 3 is not particularly limited, if it is too thin, the adhesive force between the PVA polymer film 2 and the protective film 4 tends to be lowered. If the adhesive layer 3 is too thick, 1) tends to increase unnecessarily, the thickness of the adhesive layer 3 is preferably 0.1 m or more, more preferably 0.2 m or more, still more preferably 0.3 m or more, and more preferably 0.5 m or more More preferably 500 m or less, more preferably 50 m or less, further preferably 20 m or less, particularly preferably 10 m or less.

&Lt; Method of producing adhesive agent &gt;

The adhesive body 1 is obtained by a process (bonding process) of bonding the PVA polymer film 2 and the protective film 4 via the adhesive of the present invention and after the bonding process, And a step of curing the adhesive (irradiation step).

[Integration process]

In the bonding process, the PVA polymer film (2) and the protective film (4) are bonded together with the adhesive of the present invention interposed therebetween. The bonding method is not particularly limited, but it is preferable that the adhesive of the present invention is applied to one or both of the surface of the PVA polymer film and the surface of the protective film, and then the PVA polymer film and the protection A method of superimposing the film is preferable. The method of applying the adhesive of the present invention to one or both of the surface of the PVA polymer film and the surface of the protective film is not particularly limited and may be, for example, a die coat, roll coat, air knife coat, A doctor roll coat, a doctor knife coat, a curtain flow coat, a spray, a wire bar, a rod coat, an immersion, and a brush application.

In addition, as a bonding method, in addition to the above, a method in which a PVA polymer film and a protective film are overlapped and then the adhesive of the present invention is infiltrated between them may be employed.

Further, the laminate obtained in the kneading step may be pressed with a roll or the like. In this case, the material of the roll may be, for example, metal or rubber. The roll on the PVA polymer film side and the roll on the protective film side may be the same material or different materials.

[Irradiation Process]

The adhesive body of the present invention can be obtained by irradiating the laminated body after the bonding with an active energy ray to cure the uncured adhesive. The active energy ray can be appropriately selected depending on the kind of various components contained in the adhesive of the present invention. Examples of the active energy ray include an electron beam, a proton ray, and a neutron ray as well as electromagnetic waves such as ultraviolet rays, infrared rays, X-rays, and? -Rays as described above. Ultraviolet rays or electron beams are preferable and ultraviolet rays are more preferable.

The active energy ray may be irradiated using a known apparatus. When an ultraviolet ray is used as an active energy ray, a metal halide lamp, a xenon lamp, a chemical lamp, an LED, or the like can be used as a high-pressure mercury lamp, ultra-high pressure mercury lamp, carbon arc, etc. emitting light in a wavelength range of 450 nm or less. When the electron beam EB is used as the active energy ray, the acceleration voltage is preferably in the range of 0.1 to 10 MeV, and the irradiation dose is preferably in the range of 1 to 500 kGy.

The amount of accumulated light of the active energy ray is not particularly limited, but is preferably in the range of 10 to 20,000 mJ / cm2, more preferably in the range of 30 to 5,000 mJ / cm2. When the accumulated light quantity of the active energy ray is excessively small, the adhesive strength between the cured PVA polymer film and the protective film tends to be lowered. On the other hand, when the accumulated light quantity of the active energy ray is excessively large, excess heat is generated in the adhesive body, and the adhesive layer or the PVA polymer film tends to deteriorate.

During the irradiation of the active energy ray or after irradiation, the curing of the adhesive may be promoted by heating, if necessary. The heating temperature is preferably in the range of 40 to 130 占 폚, and more preferably in the range of 50 to 100 占 폚, from the viewpoints of the curing rate and the effect on each layer.

By curing the adhesive of the present invention, an adhesive layer is formed, and the adhesive body of the present invention is obtained.

&Lt; Other Embodiments &gt;

The adhesive body of the present invention may have a plurality of adhesive layers. For example, in the PVA polymer film, another protective film may be laminated on the opposite side of the adhesive layer from the PVA polymer film, on the side opposite to the side where the adhesive layer is formed as described above, , And may have a structure of protective film / adhesive layer / PVA polymer film / adhesive layer / protective film.

When the adhesive body of the present invention is a polarizing plate, the polarizing plate may be coated with a pressure-sensitive adhesive such as an acryl-based adhesive and then applied to a glass substrate to be used as a component of an LCD. At the same time, it may be laminated with a retardation film, a viewing angle improving film, a luminance improving film or the like.

Example

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited by these examples. The following evaluation and measurement methods employed in the following Examples and Comparative Examples are shown below.

Evaluation of adhesion

The polarizing plate obtained in each of the following Examples and Comparative Examples was further allowed to stand at a temperature of 23 캜 and a relative humidity of 50% for 24 hours and then stretched from the polarizing plate in the longitudinal direction (stretching direction of the polarizing film) And five pieces of short film pieces each having a size of 25 mm were cut out in each of the Examples and Comparative Examples. Next, the polarizing film and one side of the polymethyl methacrylate film were peeled for each film piece in accordance with the T-type peeling test based on JIS K 6854-3: 1999, and the average value of the peeling forces As an adhesive force. The measurement conditions in this test were a peeling speed of 30 mm / min. Further, when the adhesion strength between the two films was too high and the polymethyl methacrylate film was broken, it was evaluated as &quot; material breakage &quot;.

Evaluation of water resistance

The polarizer obtained in each of the following Examples and Comparative Examples was immersed in water at 60 占 폚 for 48 hours. Thereafter, the polarizing plate was pulled up from the water, and the presence or absence of peeling between the polarizing film and the polymethyl methacrylate film was evaluated based on the following criteria.

A: No peeling

B: In peeling

water Contact angle  How to measure

A 50 mm-thick film piece was cut out from the polymethylmethacrylate film to be measured and the water contact angle on the side of the film contacting the adhesive was measured according to JIS R 3257: 1999 (wettability of the substrate glass surface Test method). That is, a water droplet of 4 占 ㎕ or less is left on the horizontally placed film piece, and from the shape of the water droplet, the radius r (mm) of the surface of the water droplet in contact with the film piece and the height h (Mm) was measured, and the water contact angle? (?) Was obtained by the following formula (1).

? = 2tan ^{- 1} (h / r) (1)

The measurement was carried out five times, and the average value was determined as the water contact angle of the film. The measurement was carried out under the conditions of a temperature of 25 DEG C and a humidity of 50% RH.

[Examples 1 to 4 and Comparative Examples 1 to 5]

&Lt; Preparation of adhesive &gt;

Each material was put into a container having a hermetically sealable stirring device at a mixing ratio shown in Table 1, and stirred for 24 hours to homogeneously mix to obtain an adhesive. The content of each material is as follows.

The &quot; PVA polymer (A) &quot;

PVA : saponified product of a homopolymer of vinyl acetate (saponification degree: 40 mol%, acetalized vinyl alcohol unit content: 0 mol%, degree of polymerization: 250).

PVB : polyvinyl butyral obtained by acetalizing a saponified product of a homopolymer of vinyl acetate with n-butylaldehyde (content of vinyl alcohol unit: 28 mol%, content of acetalized vinyl alcohol unit: 70 mol%, vinyl ester unit Content: 2 mol%, degree of polymerization: 500).

&Quot; Polyol &quot;

PO- 1 : Polyester polyol (Kuraraypolyol P-5010, manufactured by Kuraray Co., Ltd.)

PO- 2 : Polycarbonate polyol ("Kuraraypolol C-2090" manufactured by Kuraray Co., Ltd.)

&Quot; Cationically polymerizable compound (B) &quot; (other than the compound (BD) which is cationically polymerizable as well as radically polymerizable as described later)

B-1 : 3-ethyl-3-hydroxymethyloxetane ("OXT-101" manufactured by Toagosei Co., Ltd.)

B-2 : 3 ', 4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate ("Celloxide 2021P" manufactured by Daicel Inc.)

&Quot; Cation polymerization initiator (C) &quot;

C-1 : 50% by mass solution of diphenyl [4- (phenylthio) phenyl] sulfonium hexafluorophosphate in propylene carbonate ("CPI-100P"

&Quot; Radical polymerizable compound (D) &quot;

D-1 : Benzyl acrylate ("Viscot 160" manufactured by Osaka Organic Chemical Industry Co., Ltd.)

D-2 : Tris (2-hydroxyethyl) isocyanurate triacrylate (ARONIX M-315, manufactured by Toagosei Co., Ltd.)

&Quot; Radical polymerization initiator (E) &quot;

E-1 : 1-Hydroxycyclohexyl phenyl ketone ("IRGACURE 184" manufactured by BASF)

&Quot; Compound (BD) which is cationically polymerizable as well as radical polymerizable &quot;

BD- 1 : 3-ethyl-3-acryloyloxymethyl oxetane ("OXE-10" manufactured by Osaka Organic Chemical Industry Co., Ltd.)

&Lt; Preparation of adhesive body (polarizing plate) &gt;

A polymethyl methacrylate film (manufactured by Kuraray Co., Ltd.) having a thickness of 50 占 퐉 and a size of 300 mm 占 100 mm was used as a protective film, and the above-mentioned adhesive was applied onto one side of this polymethyl methacrylate film using a bar coater Respectively. Next, a polarizing film having a thickness of 10 占 퐉, 280 mm in the stretching direction, and 80 mm in the width direction (the PVA polymer film was produced by performing dyeing with a iodine dye and uniaxial stretching) ) Was superimposed on the protective film. Thereafter, the same adhesive as described above was coated on the side of the polarizing film not in contact with the adhesive, and another protective film was formed by using a polymethyl methacrylate having a thickness of 50 mu m and a size of 300 mm x 100 mm A film (manufactured by Kuraray Co., Ltd.) was superimposed on the polarizing film via the adhesive. The laminate having the layer structure of the polymethylmethacrylate film / adhesive / polarizing film / adhesive / poly (methyl methacrylate) film thus obtained was pressed by passing through a laminator, and the thickness of the adhesive portion was 1 Mu m.

Thereafter, an ultraviolet ray irradiating device (using a metal halide lamp of GS YUASA Co., Ltd. as a lamp) was used and the laminate was irradiated with ultraviolet rays so that the accumulated light quantity became 700 mJ / cm 2. The accumulated light quantity was measured using a UV meter (GS YUASA Co., Ltd.). After irradiated with ultraviolet light, the polarizing plate was obtained as an adhesive body by standing at a temperature of 23 캜 and a relative humidity of 50% for 24 hours. For each of the Examples and Comparative Examples, two polarizing plates were prepared to evaluate the adhesive strength and one polarizing plate to evaluate the water resistance. In Examples 3 and 4, the two polymethyl methacrylate films used in the production of the respective polarizing plates were polymethyl methacrylate obtained by corona treatment on the side of the two polymethyl methacrylate films that were in contact with the adhesive, Film was used.

<Evaluation>

The above polarizing plate was evaluated for adhesion strength and water resistance by the above-mentioned method. The results are shown in Table 1.

1: Adhesive
2: PVA polymer film
3: Adhesive layer
4: Protective film

Claims (13)

(A), a cationic polymerizable compound (B) and a cationic polymerization initiator (C) as an adhesive for bonding a protective film and a film containing a polyvinyl alcohol polymer, Curing type adhesive. The method according to claim 1,
Further comprising a radically polymerizable compound (D) and a radical polymerization initiator (E). 3. The method according to claim 1 or 2,
Wherein the at least part of the cationically polymerizable compound (B) is a compound (BD) which is both cationically polymerizable and radically polymerizable. 4. The method according to any one of claims 1 to 3,
Wherein the polyvinyl alcohol polymer (A) is a polyvinyl alcohol having an acetalized vinyl alcohol unit content of less than 10 mol% and a saponification degree of 80 mol% or less. 4. The method according to any one of claims 1 to 3,
Wherein the polyvinyl alcohol polymer (A) is a polyvinyl acetal having a content of acetalized vinyl alcohol units of 10 mol% or more. 6. The method of claim 5,
Wherein the polyvinyl acetal is polyvinyl butyral. 7. The method according to any one of claims 1 to 6,
Wherein the content of the polyvinyl alcohol polymer (A) is 1 to 90% by mass. An adhesive material comprising a film comprising a polyvinyl alcohol polymer, a protective film, and an adhesive layer, wherein the adhesive layer is disposed between the film comprising the polyvinyl alcohol polymer and the protective film, 8. An adhesive body obtained by curing the adhesive according to any one of claims 1 to 7. 9. The method of claim 8,
Wherein the film comprising the polyvinyl alcohol-based polymer is a stretched film. 10. The method according to claim 8 or 9,
Wherein the stretched film is a polarizing film or a retardation film. 11. The method according to any one of claims 8 to 10,
Wherein the protective film comprises triacetyl cellulose, a (meth) acrylic polymer, a polyester, or a polymer containing an alicyclic structure. The method according to any one of claims 8 to 11,
Wherein the adhesive force between the film comprising the polyvinyl alcohol polymer and the protective film is 6.0 N / 25 mm or more. A film comprising a polyvinyl alcohol polymer and a protective film are laminated via the adhesive described in any one of claims 1 to 7 and then the active energy ray is irradiated to cure the adhesive layer A method for manufacturing an adhesive body.

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