KR20220018090A - Adhesive layer-equipped polarization film, and image display device - Google Patents

Abstract

An object of this invention is to provide the polarizing film which has an adhesive layer which can solve the subject of a yield fall, and can provide sufficient ultraviolet-ray cut function, also when a polarizing film is thin. Moreover, an object of this invention is also to provide the image display apparatus using the polarizing film which has the said adhesive layer. In an image display apparatus, it is a polarizing film which has an adhesive layer used on the visual recognition side rather than an image display part, The polarizing film which has the said adhesive layer has an adhesive layer on both surfaces of a polarizing film and the said polarizing film, The said polarizing film is a polarizer and A transparent protective film is provided on both surfaces of the polarizer, the transparent protective film on the viewing side of the polarizer has a transmittance of 6% or more at a wavelength of 380 nm, and the adhesive layer on the viewing side of the polarizing film has an ultraviolet absorption function It is a polarizing film with an adhesive layer characterized by having it.

Description

A polarizing film having an adhesive layer, and an image display device {ADHESIVE LAYER-EQUIPPED POLARIZATION FILM, AND IMAGE DISPLAY DEVICE}

This invention relates to the polarizing film which has an adhesive layer used for an image display apparatus. Moreover, this invention relates to the image display apparatus using the polarizing film which has the said adhesive layer. Examples of the image display device include a liquid crystal display device, an organic EL (electroluminescence) display device, a PDP (plasma display panel), and electronic paper.

For a liquid crystal display device, an organic EL display device, etc., from the image formation method, for example, in a liquid crystal display device, it is indispensable to arrange|position a polarizing element on both sides of a liquid crystal cell, and a polarizing film is generally adhere|attached. In addition to the polarizing film, various optical elements have been used in display panels such as liquid crystal panels and organic EL panels to improve display quality of displays.

The polarizing film used for these image display apparatuses generally has a structure which clamps a polarizer with two protective films, and triacetyl cellulose (TAC) is widely used as a protective film.

In recent years, with the flow of weight reduction and thinning of an image display apparatus, thin film formation is calculated|required with respect to each member used for an image display apparatus, and thin film formation is calculated|required also about the protective film of a polarizing film. When the thickness of the protective film becomes thin, ultraviolet rays incident on the image display device cannot be sufficiently cut, and not only the polarizer but also various optical members including liquid crystal panels and organic EL elements used in the image display device are deteriorated by ultraviolet rays. There were problems such as speeding up the

In order to solve such a problem, for example, it is a double-sided adhesive sheet for integrating two members by arranging between the surface protection panel in an image display device and the viewing side of a liquid crystal module, and having at least one ultraviolet-absorbing layer, , a transparent double-sided adhesive sheet for an image display device having a light transmittance of 30% or less at a wavelength of 380 nm and a visible light transmittance of 80% or more on a longer wavelength side than a wavelength of 430 nm (see, for example, Patent Document 1), and an acrylic polymer And the adhesive sheet which has an adhesive layer containing a triazine type|system|group ultraviolet absorber is known (for example, refer patent document 2). Moreover, in the adhesive optical film in which the adhesive layer is provided in the single side|surface or both surfaces of an optical film, it is known that the said adhesive layer can provide ultraviolet-ray absorption (for example, refer patent document 3).

Japanese Patent Laid-Open No. 2012-211305 Japanese Patent Laid-Open No. 2013-75978 Japanese Patent No. 4208187 Publication

Although it is known in recent years to join various members used for an image display apparatus using the transparent adhesive which has an ultraviolet-ray absorption function as described in patent documents 1 - 3, in this case, thickness nonuniformity generate|occur|produces or yield deteriorates. , there were challenges in terms of workability, etc.

Then, this invention aims at providing the polarizing film which has an adhesive layer which can solve the subject of a yield fall, and can provide sufficient ultraviolet-ray cut function also when a polarizing film is thin. Moreover, an object of this invention is also to provide the image display apparatus using the polarizing film which has the said adhesive layer.

MEANS TO SOLVE THE PROBLEM As a result of repeating earnest examination in order to solve the said subject, the present inventors found out the polarizing film which has the following adhesive layer, and came to complete this invention.

That is, this invention is a polarizing film which has an adhesive layer used for the visual recognition side rather than an image display part in an image display apparatus,

The polarizing film having the pressure-sensitive adhesive layer has pressure-sensitive adhesive layers on both surfaces of the polarizing film and the polarizing film,

The polarizing film has a polarizer and a transparent protective film on both surfaces of the polarizer,

The transmittance of the transparent protective film on the visual side of the polarizer at a wavelength of 380 nm is 6% or more,

It is related with the polarizing film which has an adhesive layer, characterized in that the adhesive layer by the side of the visual recognition of the said polarizing film has a ultraviolet-ray absorption function.

The transparent protective film on the viewing side of the polarizer is at least one film selected from the group consisting of a triacetyl cellulose film, an acrylic film, a polyethylene terephthalate film, and a polyolefin film having a cyclo or norbornene structure, and It is preferable that thickness is 40 micrometers or less.

It is preferable that the thickness of the adhesive layer by the side of the visual recognition of the said polarizing film is 2 times or more of the thickness of the adhesive layer by the side of the image display part of the said polarizing film.

It is preferable that the transmittance|permeability of wavelength 380nm is 40 % or less, and, as for the adhesive layer by the side of the visual recognition of the said polarizing film, the transmittance|permeability of wavelength 400nm is 30 % or more.

It is preferable that b* value of the adhesive layer by the side of the visual recognition of the said polarizing film is 3.0 or less.

It is preferable that the adhesive layer by the side of the visual recognition of the said polarizing film contains the acrylic polymer as a base polymer.

It is preferable to use the polarizing film which has an adhesive layer of this invention for a liquid crystal display device or organic electroluminescent display.

Moreover, this invention relates to the image display apparatus characterized by using the polarizing film which has the said adhesive layer on the visual recognition side rather than an image display part.

Since the polarizing film having an adhesive layer of the present invention has a configuration in which an adhesive layer having an ultraviolet absorption function is laminated in advance on the visual recognition side of the polarizing film, it is possible to solve the problems of process reduction and yield reduction, and the polarizing film is thin Even in this case, a sufficient UV-cutting function can be provided. Furthermore, since the image display apparatus of this invention uses the polarizing film which has the said adhesive layer, deterioration by ultraviolet-ray of various optical members including the liquid crystal panel used for an image display apparatus, organic electroluminescent element, etc. can be suppressed have.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one Embodiment of the polarizing film which has an adhesive layer of this invention.
It is sectional drawing which shows typically one Embodiment of the image display apparatus of this invention.
It is sectional drawing which shows typically one Embodiment of the image display apparatus of this invention.
It is sectional drawing which shows typically one Embodiment of the image display apparatus of this invention.

1. Polarizing film having an adhesive layer

The polarizing film which has an adhesive layer of this invention is used for the visual recognition side rather than an image display part in an image display apparatus,

The polarizing film having the pressure-sensitive adhesive layer has pressure-sensitive adhesive layers on both surfaces of the polarizing film and the polarizing film,

The polarizing film has a polarizer and a transparent protective film on both surfaces of the polarizer,

The transmittance of the transparent protective film on the visual side of the polarizer at a wavelength of 380 nm is 6% or more,

It is characterized in that the adhesive layer of the visual recognition side of the said polarizing film has a ultraviolet-ray absorption function.

As shown in FIG. 1, the polarizing film 1 which has an adhesive layer of this invention is visual recognition side adhesive layer 2a/visible side transparent protective film 3a/polarizer 4/image display part side transparent protective film (3b) The structure containing the / image display part side adhesive layer 2b may just be sufficient, and the structure containing retardation film etc. may be sufficient. Specifically, the viewer side pressure-sensitive adhesive layer (2a) / the viewer side transparent protective film (3a) / the polarizer (4) / the image display section side transparent protective film (3b) / the image display section side pressure sensitive adhesive layer (2b) / retardation film (not shown) )/image display unit side pressure-sensitive adhesive layer (not shown) may be configured. The polarizing film 5 is comprised from the transparent protective film 3a on the viewer side / the polarizer 4 / the transparent protective film 3b by the image display part side. Each layer will be described in detail below.

(1) Adhesive layer on the viewer side

In this invention, it is characterized by the above-mentioned that the adhesive layer (visible side adhesive layer) on the side of the visual recognition of the said polarizing film has a ultraviolet-ray absorption function. The visual pressure-sensitive adhesive layer may have an ultraviolet absorption function, and the composition thereof is not particularly limited.

An appropriate pressure-sensitive adhesive may be used to form the visual-visible pressure-sensitive adhesive layer, and the type thereof is not particularly limited. Examples of the pressure-sensitive adhesive include a rubber pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a vinyl alkyl ether pressure-sensitive adhesive, a polyvinyl alcohol pressure-sensitive adhesive, a polyvinylpyrrolidone pressure-sensitive adhesive, a polyacrylamide pressure-sensitive adhesive, and a cellulose pressure-sensitive adhesive. Among these pressure-sensitive adhesives, an acrylic pressure-sensitive adhesive is preferably used because it is excellent in optical transparency, exhibits moderate adhesiveness, cohesiveness, and adhesive properties, and is excellent in weather resistance, heat resistance, and the like. The acrylic pressure-sensitive adhesive contains an acrylic polymer as a base polymer.

The visual pressure-sensitive adhesive layer using the acrylic pressure-sensitive adhesive includes, for example, a monomer component containing an alkyl (meth)acrylate and/or a partial polymer of the monomer component, a UV absorber, and a photopolymerization initiator having an absorption band at a wavelength of 400 nm or more ( It is preferable to form by ultraviolet-polymerizing the ultraviolet curable acrylic adhesive composition containing A). The pressure-sensitive adhesive layer formed by UV polymerization of the UV-curable acrylic pressure-sensitive adhesive composition is preferable because it is possible to form a thickness of 150 µm or more, and thus a pressure-sensitive adhesive layer having a wide thickness can be formed.

As said alkyl (meth)acrylate, what has a linear or branched C1-C24 alkyl group at the ester terminal can be illustrated. Alkyl (meth)acrylate can be used individually by 1 type or in combination of 2 or more type. In addition, alkyl (meth) acrylate refers to an alkyl acrylate and/or an alkyl methacrylate, and has the same meaning as (meth) in the present invention.

As said alkyl (meth)acrylate, the alkyl (meth)acrylate which has the said C4-9 branch can be illustrated, for example. The said alkyl (meth)acrylate is preferable at the point which is easy to balance an adhesive characteristic. Specifically, n-butyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, n-pentyl (meth) acrylate, isopentyl ( Meth) acrylate, isohexyl (meth) acrylate, isoheptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, etc. are mentioned. And these can be used individually by 1 type or in combination of 2 or more types.

In the present invention, the alkyl (meth) acrylate having an alkyl group having 1 to 24 carbon atoms at the ester terminal is preferably 40 wt % or more based on the total amount of the monofunctional monomer component forming the (meth) acrylic polymer, 50 Weight % or more is more preferable, and 60 weight% or more is still more preferable.

As the said monomer component, it can contain copolymerization monomers other than the said alkyl (meth)acrylate as a monofunctional monomer component. A copolymerization monomer can be used as the remainder of the said alkyl (meth)acrylate in a monomer component.

As a copolymerization monomer, a cyclic nitrogen-containing monomer can be contained, for example. As the cyclic nitrogen-containing monomer, those having a polymerizable functional group having an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group, and having a cyclic nitrogen structure can be used without particular limitation. The cyclic nitrogen structure preferably has a nitrogen atom in the cyclic structure. Examples of the cyclic nitrogen-containing monomer include lactam-based vinyl monomers such as N-vinylpyrrolidone, N-vinyl-ε-caprolactam, and methylvinylpyrrolidone; and vinyl monomers having a nitrogen-containing heterocycle, such as vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, and vinylmorpholine. . Moreover, the (meth)acryl monomer containing heterocyclic rings, such as a morpholine ring, a piperidine ring, a pyrrolidine ring, and a piperazine ring, is mentioned. Specific examples thereof include N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, and N-acryloylpyrrolidine. Among the cyclic nitrogen-containing monomers, a lactam-based vinyl monomer is preferable.

In the present invention, the cyclic nitrogen-containing monomer is preferably 0.5 to 50% by weight, more preferably 0.5 to 40% by weight, and 0.5 to 30% by weight based on the total amount of the monofunctional monomer component forming the (meth)acrylic polymer. % by weight is more preferred.

The monomer component used in the present invention may include a hydroxyl group-containing monomer as a monofunctional monomer component. As the hydroxyl group-containing monomer, those having a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and having a hydroxyl group can be used without particular limitation. As the hydroxyl group-containing monomer, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate ) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12- hydroxyalkyl (meth)acrylates such as hydroxylauryl (meth)acrylate; Hydroxyalkylcycloalkane (meth)acrylates, such as (4-hydroxymethylcyclohexyl)methyl (meth)acrylate, are mentioned. In addition, hydroxyethyl (meth)acrylamide, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, etc. are mentioned. These may be used alone or in combination. Among these, hydroxyalkyl (meth)acrylate is suitable.

In the present invention, the hydroxyl group-containing monomer is preferably 1 wt% or more, and more preferably 2 wt% or more, from the viewpoint of increasing adhesion and cohesion with respect to the total amount of the monofunctional monomer component forming the (meth)acrylic polymer Preferably, it is more preferable that it is 3 weight% or more. On the other hand, when the amount of the hydroxyl group-containing monomer is too large, the pressure-sensitive adhesive layer may become hard and the adhesive force may decrease, and the viscosity of the pressure-sensitive adhesive may become excessively high or gelled. It is preferable that it is 30 weight% or less with respect to the whole amount of the monofunctional monomer component which forms a (meth)acrylic-type polymer, 27 weight% or less is more preferable, and 25 weight% or less is still more preferable.

Moreover, as a monomer component which forms a (meth)acrylic-type polymer, other functional group containing monomers can be contained as a monofunctional monomer, For example, a carboxyl group containing monomer and the monomer which has a cyclic ether group are mentioned.

As a carboxyl group-containing monomer, what has a polymerizable functional group which has an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group, and has a carboxyl group can be used without restriction|limiting in particular. Examples of the carboxyl group-containing monomer include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid, and the like. It can be used individually or in combination. Itaconic acid and maleic acid can use these anhydrides. Among these, acrylic acid and methacrylic acid are preferable, and acrylic acid is especially preferable. In addition, as the monomer component used in the production of the (meth)acrylic polymer of the present invention, a carboxyl group-containing monomer may be arbitrarily used, and on the other hand, it is not necessary to use a carboxyl group-containing monomer.

As the monomer having a cyclic ether group, a monomer having a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and having a cyclic ether group such as an epoxy group or an oxetane group can be used without particular limitation. Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate glycidyl ether. . Examples of the oxetane group-containing monomer include 3-oxetanylmethyl (meth)acrylate, 3-methyl-oxetanylmethyl (meth)acrylate, 3-ethyl-oxetanylmethyl (meth)acrylate; 3-butyl-oxetanylmethyl (meth)acrylate, 3-hexyl-oxetanylmethyl (meth)acrylate, etc. are mentioned. These may be used alone or in combination.

In the present invention, the carboxyl group-containing monomer and the monomer having a cyclic ether group are preferably 30 wt% or less, more preferably 27 wt% or less, based on the total amount of the monofunctional monomer component forming the (meth)acrylic polymer, 25% by weight or less is more preferable.

As a monomer component forming the (meth)acrylic polymer of the present invention, as a copolymerized monomer, for example, CH ₂ =C(R ¹ )COOR ² (R ¹ is hydrogen or a methyl group, R ² is a C 1 to 3 and alkyl (meth)acrylates represented by a substituted alkyl group or a cyclic cycloalkyl group.

Here, the substituent of the substituted alkyl group having 1 to 3 carbon atoms as R ² is preferably an aryl group having 3 to 8 carbon atoms or an aryloxy group having 3 to 8 carbon atoms. Although it does not limit as an aryl group, A phenyl group is preferable.

Examples of such a monomer represented by CH ₂ =C(R ¹ )COOR ² include phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, 3,3,5-trimethylcyclo Hexyl (meth)acrylate, isobornyl (meth)acrylate, etc. are mentioned. These may be used alone or in combination.

In the present invention, the (meth)acrylate represented by CH ₂ =C(R ¹ )COOR ² may be used in an amount of 50% by weight or less, based on the total amount of the monofunctional monomer component forming the (meth)acrylic polymer, and , 45 weight% or less is preferable, 40 weight% or less is more preferable, and 35 weight% or less is still more preferable.

Examples of other copolymer monomers include vinyl acetate, vinyl propionate, styrene, and α-methylstyrene; glycol-based acrylic ester monomers such as (meth)acrylic acid polyethylene glycol, (meth)acrylic acid polypropylene glycol, (meth)acrylic acid methoxyethylene glycol, and (meth)acrylic acid methoxypolypropylene glycol; acrylic acid ester-based monomers such as (meth)acrylic acid tetrahydrofurfuryl, fluorine (meth)acrylate, silicone (meth)acrylate and 2-methoxyethyl acrylate; An amide group-containing monomer, an amino group-containing monomer, an imide group-containing monomer, N-acryloylmorpholine, a vinyl ether monomer and the like can also be used. Moreover, as a copolymerization monomer, the monomer which has cyclic structures, such as terpene (meth)acrylate and dicyclopentanyl (meth)acrylate, can be used.

Moreover, the silane-type monomer etc. containing a silicon atom are mentioned. Examples of the silane-based monomer include 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, and 8- Vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltri Ethoxysilane, 10-acryloyloxydecyl triethoxysilane, etc. are mentioned.

As the monomer component forming the (meth)acrylic polymer of the present invention, in addition to the monofunctional monomer of the above example, a polyfunctional monomer may be contained as necessary in order to adjust the cohesive force of the pressure-sensitive adhesive.

The polyfunctional monomer is a monomer having at least two polymerizable functional groups having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group, for example, (poly)ethylene glycol di(meth)acrylate, (poly) Propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,2-ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetra Ester compounds of polyhydric alcohols and (meth)acrylic acid, such as methylol methane tri(meth)acrylate; Allyl (meth) acrylate, vinyl (meth) acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl di (meth) acrylate, hexyl di (meth) acrylate, and the like. have. Among these, trimethylolpropane tri(meth)acrylate, hexanediol di(meth)acrylate, and dipentaerythritol hexa(meth)acrylate can be used suitably. A polyfunctional monomer can be used individually by 1 type or in combination of 2 or more type.

Although the amount of the polyfunctional monomer used varies depending on the molecular weight or the number of functional groups, it is preferably used in an amount of 3 parts by weight or less, more preferably 2 parts by weight or less, and 1 part by weight or less with respect to 100 parts by weight of the total of the monofunctional monomers. is more preferable. Moreover, although it does not specifically limit as a lower limit, It is preferable that it is 0 weight part or more, and it is more preferable that it is 0.001 weight part or more. Adhesive force can be improved by the usage-amount of a polyfunctional monomer within the said range.

In the present invention, a partial polymer of the monomer component may be used.

Although it does not specifically limit as a ultraviolet absorber contained in the said ultraviolet curable acrylic adhesive composition, For example, triazine-type ultraviolet absorber, benzotriazole-type ultraviolet absorber, benzophenone-type ultraviolet absorber, oxybenzophenone-type ultraviolet absorber, salicylic acid ester-type ultraviolet absorber, A cyanoacrylate type ultraviolet absorber etc. are mentioned, These can be used individually by 1 type or in combination of 2 or more type. Among these, triazine-based UV absorbers and benzotriazole-based UV absorbers are preferable, triazine-based UV absorbers having two or less hydroxyl groups in one molecule, and benzotriazole-based UV absorbers having one benzotriazole skeleton in one molecule. It is preferable that it is at least 1 sort(s) of ultraviolet absorber selected from the group which consists of it has favorable solubility with respect to the monomer used for formation of an ultraviolet curable acrylic adhesive composition, and also has high ultraviolet-absorbing ability in wavelength 380nm vicinity.

As a triazine type ultraviolet absorber which has two or less hydroxyl groups in 1 molecule, specifically, 2, 4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6- (4-methoxyphenyl)-1,3,5-triazine (Tinosorb S, manufactured by BASF), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibu Toxyphenyl)-1,3,5-triazine (TINUVIN 460, manufactured by BASF), 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl) Reaction product of 5-hydroxyphenyl with [(C10-C16 (mainly C12-C13)alkyloxy)methyl]oxirane (TINUVIN 400 from BASF), 2-[4,6-bis(2,4-dimethyl Phenyl)-1,3,5-triazin-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol, 2-(2,4-dihydroxyphenyl)- Reaction product of 4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)-glycidic acid ester (TINUVIN 405, manufactured by BASF), 2-(4, 6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol (TINUVIN 1577, manufactured by BASF), 2-(4,6-diphenyl-1,3 ,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]-phenol (ADK STAB LA46, manufactured by ADEKA), 2-(2-hydroxy-4-[1 -Octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine (TINUVIN 479, BASF Corporation make) etc. are mentioned.

Further, as a benzotriazole-based ultraviolet absorbent having one benzotriazole skeleton in one molecule, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1, 1,3,3-tetramethylbutyl)phenol (TINUVIN 928, manufactured by BASF), 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (TINUVIN PS, manufactured by BASF), benzenepropane Ester compound of acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy (C7-9 branched and straight chain alkyl) (TINUVIN 384-2, BASF Manufactured), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN 900, manufactured by BASF), 2-(2H-benzotriazole- 2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN 928, manufactured by BASF), methyl-3-(3-( 2H-benzotriazol-2-yl)-5-t-butyl-4-hydroxyphenyl)propionate/reaction product of polyethylene glycol 300 (TINUVIN 1130, manufactured by BASF), 2-(2H-benzotriazole- 2-yl)-p-cresol (TINUVIN P, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN 234, BASF), 2- [5-chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol (TINUVIN 326, manufactured by BASF), 2- (2H-benzotria Zol-2-yl)-4,6-di-tert-pentylphenol (TINUVIN 328, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3- Tetramethylbutyl)phenol (TINUVIN 329, manufactured by BASF), methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate and polyethylene glycol 300 (TINUVIN 213, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (TINUVIN 571, manufactured by BASF), 2-[2-hydroxy- 3-(3,4,5,6-tetrahydrophthalimidemethyl)-5-methylphene nil] benzotriazole (Sumisorb 250, manufactured by Sumitomo Chemical Co., Ltd.) and the like.

Moreover, as said benzophenone-type ultraviolet absorber (benzophenone-type compound) and an oxybenzophenone-type ultraviolet absorber (oxybenzophenone-type compound), 2, 4- dihydroxybenzophenone, 2-hydroxy-4-methyl Toxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (anhydrous and trihydrate), 2-hydroxy-4-octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone , 4-benzyloxy-2-hydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzophenone, etc. are mentioned. have.

Moreover, as said salicylic acid ester type|system|group ultraviolet absorber (salicylic acid ester type compound), For example, phenyl-2-acryloyloxybenzoate, phenyl-2-acryloyloxy-3-methylbenzoate, phenyl-2-acrylo Iloxy-4-methylbenzoate, phenyl-2-acryloyloxy-5-methylbenzoate, phenyl-2-acryloyloxy-3-methoxybenzoate, phenyl-2-hydroxybenzoate, phenyl -2-hydroxy-3-methylbenzoate, phenyl-2-hydroxy-4methylbenzoate, phenyl-2-hydroxy-5-methylbenzoate, phenyl2-hydroxy-3-methoxybenzoate, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate (TINUVIN 120, manufactured by BASF); and the like.

Examples of the cyanoacrylate-based ultraviolet absorber (cyanoacrylate-based compound) include alkyl-2-cyanoacrylate, cycloalkyl-2-cyanoacrylate, alkoxyalkyl-2-cyanoacrylate, Alkenyl-2-cyanoacrylate, alkynyl-2-cyanoacrylate, etc. are mentioned.

The ultraviolet absorber may be used alone or in combination of two or more, but the content as a whole is about 0.1 to 5 parts by weight based on 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer. It is preferable, and it is more preferable that it is about 0.5-3 weight part. By making the addition amount of a ultraviolet absorber into the said range, since the ultraviolet-absorbing function of an adhesive layer can fully be exhibited and it does not become interference with ultraviolet polymerization, it is preferable.

It is preferable that the ultraviolet curable acrylic adhesive composition used by this invention contains the photoinitiator (A) which has an absorption band at a wavelength of 400 nm or more. When an ultraviolet absorber is included in an adhesive composition, when ultraviolet-ray polymerization is performed, an ultraviolet-ray is absorbed by the said ultraviolet absorber, and it was a thing which did not fully superpose|polymerize. However, since the ultraviolet-curable acrylic pressure-sensitive adhesive composition used in the present invention has a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more, it can sufficiently polymerize despite containing an ultraviolet absorber.

As the photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Irgacure 819, manufactured by BASF), 2,4,6-trimethylbenzoyl-diphenyl- and phosphine oxide (LUCIRIN TPO, manufactured by BASF).

The photoinitiator (A) which has an absorption band in the said wavelength 400nm or more may be used independently, and may mix and use 2 or more types.

In addition, the addition amount of the photoinitiator (A) having an absorption band at the wavelength of 400 nm or more is not particularly limited, but is preferably smaller than the amount of the ultraviolet absorber added, and 100 parts by weight of a monofunctional monomer component forming a (meth)acrylic polymer It is preferable that it is about 0.005-1 weight part with respect to, and it is more preferable that it is about 0.02-0.5 weight part. When the addition amount of a photoinitiator (A) is the said range, since ultraviolet-ray polymerization can fully advance, it is preferable.

Moreover, the photoinitiator (B) which has an absorption band in wavelength less than 400 nm can be contained in the ultraviolet curable acrylic adhesive composition used by this invention. Moreover, it is preferable that a photoinitiator (B) does not have an absorption band at a wavelength of 400 nm or more. The photopolymerization initiator (B) is not particularly limited as long as it generates radicals by ultraviolet rays to initiate photopolymerization, and has an absorption band at a wavelength of less than 400 nm, and all commonly used photoinitiators can be suitably used. For example, benzoin ether-based photopolymerization initiator, acetophenone-based photopolymerization initiator, α-ketol-based photopolymerization initiator, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzyl-based photopolymerization initiator, benzophenone-based photopolymerization initiator, ketal-based photopolymerization initiator , a thioxanthone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, and the like can be used.

Specifically, as a benzoin ether type photoinitiator, For example, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1 , 2-diphenylethan-1-one, anisole methyl ether, and the like.

Examples of the acetophenone-based photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenyl ketone, 4-phenoxydichloroacetophenone, 4 -t-butyldichloroacetophenone etc. are mentioned.

As the α-ketol-based photopolymerization initiator, for example, 2-methyl-2-hydroxypropiophenone, 1-[4-(2-hydroxyethyl)phenyl]-2-hydroxy-2-methylpropane-1- On and so on.

Examples of the photoactive oxime-based photopolymerization initiator include 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime.

As a benzoin type photoinitiator, benzoin etc. are mentioned, for example.

As a benzyl-type photoinitiator, benzyl etc. are contained, for example.

Examples of the benzophenone-based photopolymerization initiator include benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, and α-hydroxycyclohexylphenylketone.

The ketal-based photopolymerization initiator includes benzyldimethyl ketal and the like.

To a thioxanthone type photoinitiator, for example, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothi oxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, dodecylthioxanthone, and the like.

Examples of the acylphosphine oxide-based photopolymerization initiator include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and the like.

The photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm can be used alone or in combination of two or more. The photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm can be added within a range that does not impair the effects of the present invention, but as an amount to be added, 100 parts by weight of a monofunctional monomer component forming a (meth)acrylic polymer It is preferable that it is about 0.005-0.5 weight part with respect to it, and it is more preferable that it is about 0.02-0.1 weight part.

In the present invention, a partial polymerization product (prepolymer composition) of a monomer component that is partially polymerized by adding a photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm to the monomer component and irradiating ultraviolet rays with a wavelength of 400 nm or more It is preferable to add the photopolymerization initiator (A) having an absorption band and an ultraviolet absorber to it and conduct ultraviolet polymerization. When adding the photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more to the partially polymerized product (prepolymer composition) of the monomer component partially polymerized by irradiation with ultraviolet light, it is preferable to add the photopolymerization initiator after dissolving the photoinitiator in the monomer. do.

In addition, the ultraviolet curable acrylic pressure-sensitive adhesive composition used in the present invention may contain a silane coupling agent. It is preferable that the compounding quantity of a silane coupling agent is 1 weight part or less with respect to 100 weight part of monofunctional monomer components which form a (meth)acrylic-type polymer, 0.01-1 weight part is more preferable, 0.02-0.6 weight part is still more preferable.

Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4epoxycyclo). Epoxy group-containing silane coupling agent such as hexyl)ethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N -(1,3-dimethylbutylidene)propylamine, amino group-containing silane coupling agent such as N-phenyl-γ-aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyl (meth)acryl group containing silane coupling agents, such as triethoxysilane, isocyanate group containing silane coupling agents, such as 3-isocyanate propyl triethoxysilane, etc. are mentioned.

The UV-curable acrylic pressure-sensitive adhesive composition used in the present invention may contain a crosslinking agent. Examples of the crosslinking agent include isocyanate crosslinking agents, epoxy crosslinking agents, silicone crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, silane crosslinking agents, alkyletherification melamine crosslinking agents, metal chelate crosslinking agents, crosslinking agents such as peroxides. A crosslinking agent can be used individually by 1 type or in combination of 2 or more types. Among these, an isocyanate type crosslinking agent is used preferably.

The crosslinking agent may be used alone or in combination of two or more, but the content as a whole is 5 parts by weight or less with respect to 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer It is preferable, It is more preferable that it is 0.01-5 weight part, 0.01-4 weight part is still more preferable, 0.02-3 weight part is especially preferable.

The isocyanate-based crosslinking agent refers to a compound having two or more isocyanate groups (including an isocyanate regeneration functional group in which the isocyanate group is temporarily protected by a blocking agent or quantification, etc.) in one molecule. Examples of the isocyanate-based crosslinking agent include aromatic isocyanates such as tolylene diisocyanate and xylene diisocyanate, alicyclic isocyanates such as isophorone diisocyanate, and aliphatic isocyanates such as hexamethylene diisocyanate.

More specifically, for example, lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; cycloaliphatic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate; 2,4- Aromatic diisocyanates such as tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate and polymethylene polyphenyl isocyanate, trimethylolpropane/tolylene diisocyanate trimer adduct (trade name: Coronate L, Nippon Polyurethane Kogyo Co., Ltd. product), trimethylolpropane/hexamethylene diisocyanate trimer adduct (trade name: Coronate HL, Nippon Polyurethane Kogyo Co., Ltd. product), isocyanurate form of hexamethylene diisocyanate ( Brand name: isocyanate adducts such as Coronate HX, manufactured by Nippon Polyurethane Kogyo Co., Ltd., trimethylolpropane adduct of xylylene diisocyanate (trade name: D110N, manufactured by Mitsui Chemicals Co., Ltd.), hexamethylene diisocyanate trimethylolpropane adduct (trade name: D160N, manufactured by Mitsui Chemicals Co., Ltd.); Polyether polyisocyanate, polyester polyisocyanate, and the polyisocyanate polyisocyanate polyfunctionalized by the addition product of these and various polyols, an isocyanurate bond, a biuret bond, an allophanate bond, etc. are mentioned.

The ultraviolet curable acrylic adhesive composition used by this invention may contain the additive suitable according to a use other than the said component. For example, a tackifier (for example, a solid, semi-solid, or liquid thing at room temperature which consists of a rosin derivative resin, a polyterpene resin, a petroleum resin, oil-soluble phenol resin, etc.); fillers such as hollow glass balloons; plasticizer; anti-aging; antioxidant etc. are mentioned.

In this invention, it is preferable to adjust the said ultraviolet curable acrylic adhesive composition to the viscosity suitable for the operation|work which performs application|coating etc. on a base material. Adjustment of the viscosity of an ultraviolet curable acrylic adhesive composition is performed, for example by adding various polymers, such as a thickening additive, a polyfunctional monomer, etc., or partial polymerization of the monomer component in an ultraviolet curable acrylic adhesive composition. In addition, the said partial polymerization may be performed before adding various polymers, such as a thickening additive, a polyfunctional monomer, etc., and may be performed after it. Since the viscosity of the UV-curable acrylic pressure-sensitive adhesive composition changes depending on the amount of additives, the polymerization rate in the case of partial polymerization of the monomer component in the UV-curable acrylic pressure-sensitive adhesive composition cannot be uniquely determined, but the target is about 20% or less. It is preferable, about 3 to 20 % is more preferable, and about 5 to 15 % is still more preferable. When it exceeds 20%, since the viscosity becomes too high, it becomes difficult to apply|coat to a base material.

The visual recognition side adhesive layer can be formed by coating the said ultraviolet curable acrylic adhesive composition on at least one side of a base material, and irradiating an ultraviolet-ray to the said ultraviolet curable acrylic adhesive composition.

It does not specifically limit as said base material, For example, various base materials, such as a release film and a transparent resin film base material, and the polarizing film mentioned later can also be used conveniently as a base material. When the visual recognition side adhesive layer is provided in base materials other than a polarizing film, the said visual recognition side adhesive layer can be bonded to a polarizing film and transcribe|transferred.

As a constituent material of the said release film, For example, resin films, such as polyethylene, polypropylene, polyethylene terephthalate, polyester film, porous materials, such as paper, cloth, and a nonwoven fabric, a net, foam sheet, metal foil, and these laminates Although suitable thin leaf bodies, such as a sieve, etc. are mentioned, A resin film is used suitably at the point excellent in surface smoothness.

Examples of the resin film include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, and a polybutylene terephthalate film. , a polyurethane film, an ethylene-vinyl acetate copolymer film, and the like.

The thickness of the release film is usually 5 to 200 μm, preferably about 5 to 100 μm. If necessary, the release film may be subjected to a release and antifouling treatment with a silicone-based, fluorine-based, long-chain alkyl- or fatty acid amide-based release agent, silica powder, or the like, or an antistatic treatment such as a coating type, kneading type, or vapor deposition type. In particular, by appropriately performing peeling treatment such as silicone treatment, long-chain alkyl treatment, or fluorine treatment on the surface of the release film, the releasability from the pressure-sensitive adhesive layer can be further improved.

Although it does not restrict|limit especially as said transparent resin film base material, Various resin films which have transparency are used. The said resin film is formed by the film of one layer. Examples of the material include polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate, acetate-based resins, polyethersulfone-based resins, polycarbonate-based resins, polyamide-based resins, polyimide-based resins, and polyolefin-based resins. Resin, (meth)acrylic-type resin, polyvinyl chloride-type resin, polyvinylidene chloride-type resin, polystyrene-type resin, polyvinyl alcohol-type resin, polyarylate-type resin, polyphenylene sulfide-type resin, etc. are mentioned. Among these, polyester-based resins, polyimide-based resins and polyethersulfone-based resins are particularly preferable.

It is preferable that the thickness of the said film base material is 15-200 micrometers, and it is more preferable that it is 25-188 micrometers.

The method of applying the ultraviolet curable acrylic pressure-sensitive adhesive composition on the substrate is a roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, curtain Appropriate known methods such as coat, lip coat, and die coater may be used, and are not particularly limited.

The illuminance of the ultraviolet ray irradiated to the ultraviolet curable acrylic pressure-sensitive adhesive composition is preferably 5 mW/cm 2 or more. When the illuminance of the ultraviolet ray is less than 5 mW/cm 2 , the polymerization reaction time becomes long and productivity may be lowered. Moreover, as for the illuminance of the said ultraviolet-ray, 200 mW/cm<2> or less is preferable. When the illuminance of the ultraviolet light exceeds 200 mW/cm 2 , the photopolymerization initiator is rapidly consumed, so that the molecular weight of the polymer is reduced, and in particular, the holding power at high temperature may be lowered. Moreover, it is preferable that the accumulated light amount of ultraviolet-ray is 100 mJ/cm<2> - 5000 mJ/cm<2>.

Although the ultraviolet lamp used for this invention is not specifically limited, LED lamp is preferable. Since an LED lamp is a lamp with a low emission heat compared with other ultraviolet lamps, the temperature during superposition|polymerization of an adhesive layer can be suppressed. Therefore, while reducing molecular weight of a polymer can be prevented and the fall of the cohesive force of an adhesive layer is prevented, the holding force in high temperature at the time of setting it as an adhesive sheet can be raised. It is also possible to combine a plurality of ultraviolet lamps. In addition, by intermittently irradiating ultraviolet rays, it is also possible to provide a bright stage irradiating ultraviolet ray and a dark stage not irradiating ultraviolet ray.

In the present invention, the final polymerization rate of the monomer component in the ultraviolet curable acrylic pressure-sensitive adhesive composition is preferably 90% or more, more preferably 95% or more, and still more preferably 98% or more.

In the present invention, the peak wavelength of the ultraviolet rays irradiated to the ultraviolet curable acrylic pressure-sensitive adhesive composition is preferably in the range of 200 to 500 nm, more preferably in the range of 300 to 450 nm. When the peak wavelength of an ultraviolet-ray exceeds 500 nm, a photoinitiator may not decompose|disassemble and a polymerization reaction may not start. Moreover, when the peak wavelength of an ultraviolet-ray is less than 200 nm, a polymer chain may be cut|disconnected and adhesive characteristic may fall.

Since the reaction is inhibited by oxygen in the air, in order to block oxygen, it is preferable to form a release film or the like on the coating layer of the acrylic pressure-sensitive adhesive composition, or to carry out the photopolymerization reaction in a nitrogen atmosphere. As a release film, the thing mentioned above is mentioned. Moreover, when a release film is used, the said release film can be used as a separator of a polarizing film which has an adhesive layer as it is.

The thickness of the visual recognition-side pressure-sensitive adhesive layer is preferably at least twice the thickness of the pressure-sensitive adhesive layer on the image display portion side (image display portion-side pressure-sensitive adhesive layer) of the polarizing film to be described later from the viewpoint of ensuring the ultraviolet absorption function, and is preferably 5 times or more It is more preferable, and it is still more preferable that it is 10 times or more. Specifically, it is preferable that the thickness of the said visual recognition side adhesive layer is 50 micrometers or more, It is more preferable that it is 100 micrometers or more, It is still more preferable that it is 150 micrometers or more. Although the upper limit of the thickness of the visual recognition side adhesive layer is not specifically limited, It is preferable that it is 10 mm or less. When the thickness of an adhesive layer exceeds 10 mm, since permeation|transmission of an ultraviolet-ray becomes difficult and superposition|polymerization of a monomer component takes time and productivity may fall, it is unpreferable.

In addition, when the UV-curable acrylic pressure-sensitive adhesive composition used in the present invention contains a photopolymerization initiator (B), the monomer component containing alkyl (meth)acrylate and the photopolymerization initiator (B) (referred to as “preaddition polymerization initiator”) In some cases, UV rays are irradiated to a composition containing Post-addition polymerization initiator”) is preferably added to prepare an ultraviolet curable acrylic pressure-sensitive adhesive composition. The polymerization rate of the partial polymer is preferably about 20% or less, more preferably about 3 to 20%, still more preferably about 5 to 15%. The UV irradiation conditions are the same as described above.

As described above, when the pressure-sensitive adhesive layer is formed from the UV-curable acrylic pressure-sensitive adhesive composition containing the photopolymerization initiator (B), the polymerization rate of the monomer component can be increased by polymerization in the two steps as described above, and also finally produced It is possible to improve the ultraviolet absorption function of the pressure-sensitive adhesive layer.

Although the gel fraction of the visual recognition side adhesive layer of this invention is not specifically limited, It is preferable that it is 50 % or more, It is more preferable that it is 75 % or more, It is still more preferable that it is 85 % or more. When the gel fraction of the visual recognition side pressure-sensitive adhesive layer is small, the cohesive force is inferior, and when it is too large, the adhesive force may be inferior.

Although the permeation|transmission b* value of the said visual recognition side adhesive layer is not specifically limited, It is preferable that it is 3.0 or less, It is more preferable that it is 1.5 or less, It is still more preferable that it is 0.5 or less. The said b* value points out the b* value (chromaticity) in the L*a*b* color system based on JIS Z8729, For example, a spectrophotometer (Product name: U4100, Hitachi High-Technologies Co., Ltd. product) can be used to measure

It is preferable that the transmittance|permeability in wavelength 380nm of the said visual recognition side adhesive layer is 40 % or less, It is more preferable that it is 20 % or less, It is still more preferable that it is 8 % or less. When the transmittance|permeability wavelength in wavelength 380nm is the said range, since an incident ultraviolet-ray can fully be interrupted|blocked, deterioration of optical members including a liquid crystal panel, an organic electroluminescent element, a polarizer, etc. can be suppressed.

It is preferable that it is 30 % or more, and, as for the transmittance|permeability in wavelength 400nm of the said visual recognition side adhesive layer, it is preferable that it is 50 % or more, It is more preferable that it is 70 % or more. When the transmittance wavelength in wavelength 400nm is the said range, since the visible light which injects can fully permeate|transmit and can ensure sufficient visibility in an image display apparatus, it is preferable.

(2) Adhesive layer on the side of the image display unit

The pressure-sensitive adhesive layer on the image display unit side surface of the polarizing film (image display unit side pressure-sensitive adhesive layer) is not particularly limited, and the same as the UV-curable acrylic pressure-sensitive adhesive composition described in detail in the above-mentioned visual display side pressure-sensitive adhesive layer may be used, and various commonly used pressure-sensitive adhesives layers can be used.

A suitable pressure-sensitive adhesive may be used for forming the pressure-sensitive adhesive layer on the surface of the image display unit side, and there is no particular limitation on the type thereof. Examples of the pressure-sensitive adhesive include a rubber pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a vinyl alkyl ether pressure-sensitive adhesive, a polyvinyl alcohol pressure-sensitive adhesive, a polyvinylpyrrolidone pressure-sensitive adhesive, a polyacrylamide pressure-sensitive adhesive, and a cellulose pressure-sensitive adhesive. Among these pressure-sensitive adhesives, an acrylic pressure-sensitive adhesive is preferably used because it is excellent in optical transparency, exhibits moderate adhesiveness, cohesiveness, and adhesive properties, and is excellent in weather resistance, heat resistance, and the like.

The acrylic pressure-sensitive adhesive uses, as a base polymer, an acrylic polymer having a monomer unit of an alkyl (meth)acrylic acid alkyl ester as a main skeleton. Examples of the (meth)acrylic acid alkyl ester constituting the main skeleton of the acrylic polymer include those similar to those used for the ultraviolet curable acrylic pressure-sensitive adhesive composition for forming the viewer-side pressure-sensitive adhesive layer. Moreover, also as a copolymerization monomer and its ratio, the thing similar to what is used for an ultraviolet curable acrylic adhesive composition is mentioned.

The acrylic polymer can be produced by various known methods, and for example, a radical polymerization method such as a bulk polymerization method, a solution polymerization method, and a suspension polymerization method can be appropriately selected. As a radical polymerization initiator, various well-known things of an azo type and a peroxide type can be used. The reaction temperature is usually about 50 to 80°C, and the reaction time is 1 to 8 hours. Moreover, the solution polymerization method is preferable among the said manufacturing methods, and ethyl acetate, toluene, etc. are generally used as a solvent of an acrylic polymer. The solution concentration is usually about 20 to 80% by weight.

Moreover, the said adhesive can be made into the adhesive composition containing a crosslinking agent. Examples of the crosslinking agent include those described above, and an isocyanate-based crosslinking agent is particularly preferable. Although the mixing ratio of the acrylic polymer and the crosslinking agent is not particularly limited, it is usually preferably about 0.001 to 20 parts by weight of the crosslinking agent (solid content) with respect to 100 parts by weight of the acrylic polymer (solid content), and more preferably about 0.01 to 15 parts by weight. .

Further, in the pressure-sensitive adhesive, if necessary, a tackifier, a plasticizer, a glass fiber, glass beads, a metal powder, a filler consisting of other inorganic powders, a pigment, a colorant, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent, etc., Moreover, various additives can also be used suitably in the range which does not deviate from the objective of this invention. Moreover, it is good also as an adhesive layer etc. which contain microparticles|fine-particles and show light diffusivity. As a silane coupling agent, the thing mentioned above is mentioned.

The image display part side adhesive layer is formed by apply|coating the said adhesive to various base materials, such as a polarizing film or a release film, and drying. When an adhesive layer is provided in various base materials, such as a release film, the said adhesive layer can be bonded to a polarizing film, and can be transcribe|transferred. As for the coating method of the said adhesive and the said various base materials, the thing similar to the coating method of the said ultraviolet curable acrylic adhesive composition, and various base materials is mentioned.

In addition, in the said application|coating process, the application amount is controlled so that the adhesive layer to be formed may become a predetermined thickness (thickness after drying). Although the thickness of the image display part side adhesive layer is not specifically limited, It is preferable that it is 1/2 or less of the thickness of the visual recognition side adhesive layer, It is preferable that it is 1/5 or less, It is preferable that it is 1/10 or less. Specifically, it is preferable that it is about 1-100 micrometers, and, as for the thickness of the adhesive layer by the side of an image display, about 3-50 micrometers is more preferable, and its about 5-30 micrometers are still more preferable.

In formation of the image display part side adhesive layer, drying is performed with respect to the apply|coated adhesive. Although the drying temperature and drying time are not specifically limited, Although it sets suitably, it is preferable that it is 0.5 to 10 minutes at about 80-200 degreeC, for example.

When the said image display part side adhesive layer is exposed, you may protect an adhesive layer with a release film until it provides practical use. Moreover, the said release film can be used as a separator of a polarizing film with an adhesive layer as it is, and simplification in a process surface is possible.

(3) Polarizing film

The polarizing film used in the present invention has a polarizer and a transparent protective film on both surfaces of the polarizer, and the transmittance at a wavelength of 380 nm of the transparent protective film on the viewing side of the polarizer (visible side transparent protective film) is 6% or more characterized.

(3-1) Visible side transparent protective film

The transmittance|permeability in wavelength 380nm of the visual recognition side transparent protective film used by this invention is 6 % or more, It is preferable that it is 10 % or more, It is more preferable that it is 15 % or more. Although it does not specifically limit about the upper limit of the transmittance|permeability in wavelength 380nm, It is preferable that it is 90 % or less, and it is more preferable that it is 30 % or less. When the transmittance of the viewing-side transparent protective film at a wavelength of 380 nm is within the above range, a thickness reduction of the viewing-side transparent protective film and sufficient ultraviolet absorption ability by combining with the viewing-side pressure-sensitive adhesive layer (containing an ultraviolet absorber) are achieved. It is preferable because it can be done. Even if the transparent protective film on the viewer side does not have the ability to absorb UV light, the UV absorption function can be sufficiently supplemented by absorption of UV light by the pressure sensitive adhesive layer on the viewer side. has Moreover, when the transmittance|permeability of the wavelength 380nm of the said visual recognition side adhesive layer is 40% or less, it is preferable from a viewpoint of ultraviolet-absorbing ability that the transmittance|permeability of the wavelength 380nm of the visual recognition side transparent protective film is 30% or less.

As a material for forming the transparent protective film on the viewing side, those having excellent transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, and the like are preferable. For example, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers such as diacetyl cellulose and triacetyl cellulose, acrylic polymers such as polymethyl methacrylate, polystyrene or acrylonitrile styrene copolymer ( AS resin), etc. styrene-type polymer, polycarbonate-type polymer, etc. are mentioned. In addition, polyethylene, polypropylene, polyolefin having a cyclo or norbornene structure, polyolefin polymer such as ethylene/propylene copolymer, vinyl chloride polymer, amide polymer such as nylon or aromatic polyamide, imide polymer, sulfone polymer Polymer, polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer, epoxy Polymers or blends of the above polymers are also exemplified as examples of the polymer forming the transparent protective film. The transparent protective film can also be formed as a cured resin layer of a thermosetting type such as an acrylic type, a urethane type, an acrylic urethane type, an epoxy type, or a silicone type, or an ultraviolet curing type. Among these, the transparent protective film on the viewer side is at least one selected from the group consisting of a triacetyl cellulose film, an acrylic film (a film using an acrylic polymer), a polyethylene terephthalate film, and a polyolefin film having a cyclo or norbornene structure. It is preferable that it is a film of , and a triacetyl cellulose film is more preferable.

Although the thickness of the visual recognition side transparent protective film is not specifically limited, It is preferable that it is 40 micrometers or less, It is more preferable that it is 35 micrometers or less, It is still more preferable that it is 30 micrometers or less. Moreover, although the lower limit of the thickness of the visual recognition side transparent protective film is not specifically limited, It is preferable that it is 1 micrometer or more. When the thickness of the visual recognition side transparent protective film is the said range, since thickness reduction of a polarizing film can fully be achieved and the protective function of a polarizer is not impaired, it is preferable.

It is preferable that the polarizer and the protective film on the viewer side, which will be described later, adhere to each other through a water-based adhesive or the like. Examples of the water-based adhesive include an isocyanate-based adhesive, a polyvinyl alcohol-based adhesive, a gelatin-based adhesive, a vinyl-based latex-based adhesive, a water-based polyurethane, and an aqueous polyester. In addition to the above, examples of the adhesive for the polarizer and the viewing-side transparent protective film include an ultraviolet curing adhesive, an electron beam curing adhesive, and the like. The adhesive for an electron beam curing type polarizing film shows suitable adhesiveness with respect to the said various visual recognition side transparent protective films. Further, the adhesive used in the present invention may contain a metal compound filler.

The hard coat layer, antireflection treatment, sticking prevention, or treatment for the purpose of diffusion or antiglare may be applied to the surface of the transparent protective film on the viewer side on which the polarizer is not adhered.

(3-2) Polarizer

A polarizer is not specifically limited, Various things can be used. As the polarizer, for example, a dichroic substance such as iodine or a dichroic dye is adsorbed to a hydrophilic polymer film such as a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, or an ethylene/vinyl acetate copolymer-based partially saponified film, and uniaxial and polyene-based oriented films such as the stretched product, a dehydration treatment product of polyvinyl alcohol, and a dehydrochloric acid treatment product of polyvinyl chloride. Among these, a polarizer made of a polyvinyl alcohol-based film and a dichroic substance such as iodine is suitable. Although the thickness in particular of these polarizers is not restrict|limited, Generally, it is about 5-80 micrometers.

A polarizer in which a polyvinyl alcohol-based film is dyed with iodine and uniaxially stretched can be produced by, for example, immersing polyvinyl alcohol in an aqueous solution of iodine, dyeing the polyvinyl alcohol-based film, and stretching the film to 3 to 7 times its original length. It can also be immersed in aqueous solution, such as potassium iodide which may contain boric acid, zinc sulfate, zinc chloride, etc. as needed. If necessary, the polyvinyl alcohol-based film may be immersed in water before dyeing and washed with water. By washing the polyvinyl alcohol-based film with water, contamination and blocking agents on the surface of the polyvinyl alcohol-based film can be washed, and by swelling the polyvinyl alcohol-based film, there is also an effect of preventing unevenness such as staining of dyeing. Extending may be performed after dyeing|staining with iodine, you may extend|stretch while dyeing|staining, and may dye|stain with iodine after extending|stretching. It can be extended also in aqueous solutions, such as boric acid and potassium iodide, and a water bath.

Moreover, in this invention, the thin-shaped polarizer whose thickness is 10 micrometers or less can also be used. It is preferable that the said thickness is 1-7 micrometers from a viewpoint of thinning. It is preferable that such a thin polarizer has little thickness nonuniformity, is excellent in visibility, and since there are few dimensional changes, it is excellent in durability, and the point which thickness as a polarizing film can also aim at thickness reduction is preferable.

As a thin-shaped polarizer, typically, Unexamined-Japanese-Patent No. 51-069644, Unexamined-Japanese-Patent No. 2000-338329, International Publication No. 2010/100917 pamphlet, International Publication No. 2010/100917 pamphlet, or Japanese Patent Publication The thin-shaped polarizing film described in the specification of 4751481 and Unexamined-Japanese-Patent No. 2012-073563 is mentioned. These thin polarizing films can be obtained by a manufacturing method including a process of extending|stretching a polyvinyl alcohol-type resin (hereinafter also referred to as a PVA-based resin) layer and a resin substrate for stretching in the state of a laminate, and a process of dyeing. According to this manufacturing method, even if the PVA-based resin layer is thin, by being supported by the resin substrate for stretching, stretching can be performed without problems such as breakage due to stretching.

Among the manufacturing methods including the process of extending|stretching and the process of dyeing as said thin-shaped polarizing film in the state of a laminated body, since it can extend|stretch at a high magnification and can improve polarization performance, International Publication No. 2010/100917 pamphlet, international It is preferable to obtain by a manufacturing method including the process of extending|stretching in the boric acid aqueous solution which has description in Unexamined-Japanese-Patent No. 2010/100917 pamphlet, or the specification of Japanese Patent No. 4751481 or Unexamined-Japanese-Patent No. 2012-073563, Especially the thing obtained by the Japanese Patent Publication It is preferable to obtain by the manufacturing method including the process of carrying out auxiliary|air_stretching auxiliary before extending|stretching in boric-acid aqueous solution with description in the specification of 4751481 or Unexamined-Japanese-Patent No. 2012-073563.

(3-3) Transparent protective film on the image display part side

About the image display side transparent protective film, what has been conventionally used can be used suitably. Specifically, a transparent protective film made of a material excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, etc. is preferable. For example, a polyester-based polymer such as polyethylene terephthalate or polyethylene naphthalate, diacetyl Cellulose polymers such as cellulose and triacetyl cellulose, acrylic polymers such as polymethyl methacrylate, styrenic polymers such as polystyrene or acrylonitrile styrene copolymer (AS resin), polycarbonate polymers, etc. have. In addition, polyethylene, polypropylene, polyolefin having a cyclo- or norbornene structure, polyolefin-based polymers such as ethylene/propylene copolymer, vinyl chloride-based polymers, amide-based polymers such as nylon or aromatic polyamide, imide-based polymers, and sulfone-based polymers Polymer, polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer, epoxy Polymers or blends of the above polymers are also exemplified as examples of the polymer forming the transparent protective film. The transparent protective film can also be formed as a cured resin layer of a thermosetting type such as an acrylic type, a urethane type, an acrylic urethane type, an epoxy type, or a silicone type, or an ultraviolet curing type.

Although the thickness of an image display part side protective film can be determined suitably, Generally, it is about 1-500 micrometers from viewpoints, such as workability|operativity, such as intensity|strength and handleability, thin film property.

The said polarizer and the transparent protective film on the side of an image display part are also closely_contact|adhered through a water-based adhesive agent etc. normally. Examples of the water-based adhesive include those described above.

The surface to which the polarizer is not adhere|attached of the said image display part side transparent protective film may be hard-coat layer, antireflection treatment, sticking prevention, and what gave the process aiming at diffusion thru|or antiglare may be sufficient.

2. Image display device

The image display device of this invention used the polarizing film which has the adhesive layer of this invention, It is characterized by the above-mentioned.

As an example of the specific configuration of the image display device, for example, as shown in Figs. 2 to 4,

Cover glass or cover plastic (6)/visible side adhesive layer (2a)/visible side transparent protective film (3a)/polarizer (4)/image display part side transparent protective film (3b)/image display part side adhesive layer (2b)/ liquid crystal display (LCD) or organic EL display (OLED) 7 (FIG. 2);

Cover glass or cover plastic (6)/adhesive layer (8a)/sensor layer (9)/visible side adhesive layer (2a)/visible side transparent protective film (3a)/polarizer (4)/image display part side transparent protective film ( 3b)/image display part side pressure-sensitive adhesive layer 2b/liquid crystal display (LCD) or organic EL display (OLED) 7 ( FIG. 3 );

Cover glass or cover plastic (6)/Adhesive layer (8a)/Sensor layer (9)/Adhesive layer (8b)/Sensor layer (9)/Visible side adhesive layer (2a)/Visual side transparent protective film (3a)/ Polarizer 4/image display unit side transparent protective film 3b/image display unit side pressure-sensitive adhesive layer 2b/liquid crystal display device (LCD) or organic EL display device (OLED) 7 ( FIG. 4 );

As mentioned above, the image display apparatus in which each layer was laminated|stacked in this order is mentioned. The polarizing film 1 having an adhesive layer of the present invention, among the above-described constitutions, "visible side adhesive layer 2a/visible side transparent protective film 3a/polarizer 4/image display part side transparent protective film 3b" /image display part side adhesive layer 2b" is said, and retardation film etc. may be included other than these. In addition, when the retardation film is included, specifically, the image display unit side pressure-sensitive adhesive layer 2b and the liquid crystal display (LCD) or organic EL display (OLED) 7 may be laminated with an adhesive layer interposed therebetween. Moreover, lamination|stacking of each layer WHEREIN: An adhesive layer and/or an adhesive bond layer can be used suitably.

Examples of the image display device include a liquid crystal display device, an organic EL (electroluminescence) display device, a PDP (plasma display panel), and electronic paper. Nessence) display devices and the like are preferable.

Example

Hereinafter, the present invention will be specifically described by way of Examples, but the present invention is not limited by these Examples. In addition, all parts and % in each example are based on weight. Evaluation items in Examples and the like were measured as follows.

Preparation Example 1 (Preparation of acrylic pressure-sensitive adhesive composition (a-1))

2-ethylhexyl acrylate (2EHA) 78 parts by weight, n-vinyl-2-pyrrolidone (NVP) 18 parts by weight, and 2-hydroxyethyl acrylic acid (HEA) in a monomer mixture consisting of 4 parts by weight 1- as a photopolymerization initiator Hydroxycyclohexylphenyl ketone (trade name: Irgacure 184, having an absorption band at a wavelength of 200 to 370 nm, manufactured by BASF) 0.035 parts by weight, 2,2-dimethoxy-1,2-diphenylethan-1-one (Brand name: Irgacure 651, having an absorption band at a wavelength of 200 to 380 nm, manufactured by BASF) After blending 0.035 parts by weight, the viscosity (measurement conditions: BH viscometer No. 5 rotor, 10 rpm, measurement temperature 30° C.) was about Ultraviolet rays were irradiated until it reached 20 Pa·s to obtain a prepolymer composition (polymerization rate: 8%) in which a part of the monomer component was polymerized. Next, 0.15 parts by weight of hexanediol diacrylate (HDDA) and 0.3 parts by weight of a silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) are added to the prepolymer composition and mixed to form an acrylic pressure-sensitive adhesive composition ( a-1) was obtained.

Preparation Example 2 (Preparation of acrylic pressure-sensitive adhesive composition (a-2))

67 parts by weight of butyl acrylate (BA), 14 parts by weight of cyclohexyl acrylate (CHA), 27 parts by weight of 4-hydroxybutyl acrylate (4HBA), 2,2-dimethoxy-1,2-di as a photopolymerization initiator Phenyl-1-one (trade name: Irgacure 651, having an absorption band at a wavelength of 200 to 380 nm, manufactured by BASF Japan) 0.05 parts by weight and 1-hydroxy-cyclohexyl-phenyl-ketone (trade name: Irgacure 184) , having an absorption band at a wavelength of 200 to 370 nm, manufactured by BASF Japan) 0.05 parts by weight in a four-neck flask, exposed to ultraviolet rays under a nitrogen atmosphere, and partially photopolymerized to obtain a partial polymer (monomer syrup) having a polymerization rate of 10% . Next, 0.15 parts by weight of dipentaerythritol penta and hexaacrylate (DPHA) and 0.3 parts by weight of a silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) are added to the partial polymer and mixed. and ultraviolet irradiation to obtain an acrylic pressure-sensitive adhesive composition (a-2).

Production Example 3 (Production of the image display part side pressure-sensitive adhesive layer (B-1))

After adding 95 parts of butyl acrylate, 5 parts of acrylic acid, 0.2 parts of azobisisobutyronitrile as a polymerization initiator, and 233 parts of ethyl acetate to a separable flask equipped with a thermometer, a stirrer, a reflux cooling tube and a nitrogen gas introduction tube, Nitrogen replacement was performed for about 1 hour while flowing nitrogen gas and stirring. Then, the flask was heated at 60 degreeC, it was made to react for 7 hours, and the weight average molecular weight (Mw) of 1.1 million acrylic polymer was obtained.

0.8 parts by weight of trimethylolpropane tolylene diisocyanate (trade name: Coronate L, manufactured by Nippon Polyurethane Kogyo Co., Ltd.) as an isocyanate-based crosslinking agent in the acrylic polymer solution (solid content is 100 parts by weight), a silane coupling agent (trade name: KBM) -403, Shin-Etsu Chemical Co., Ltd. product) 0.1 part was added, and the adhesive composition (solution) was prepared.

On a 38 µm-thick separator (a polyethylene terephthalate-based film whose surface has been peeled off), the obtained pressure-sensitive adhesive composition solution is applied to a thickness of 12 µm after drying, dried at 100°C for 3 minutes to remove the solvent, and the pressure-sensitive adhesive layer got Then, it crosslinked by heating at 50 degreeC for 48 hours. Hereinafter, this adhesive layer is called "image display part side adhesive layer (B-1)."

Production Example 4 (Production of the image display part side pressure-sensitive adhesive layer (B-2))

On a 38 µm-thick separator (a polyethylene terephthalate-based film with a release-treated surface), the pressure-sensitive adhesive composition solution obtained in Preparation Example 3 was applied to a thickness of 15 µm after drying, and dried at 100° C. for 3 minutes to remove the solvent. It removed to obtain an adhesive layer. Then, it crosslinked by heating at 50 degreeC for 48 hours. Hereinafter, this adhesive layer is called "image display part side adhesive layer (B-2)."

Example 1

(Preparation of a pressure-sensitive adhesive composition having a UV absorption function)

2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]- which was dissolved in the obtained acrylic pressure-sensitive adhesive composition (a-1) in butyl acrylate to a solid content of 15% 1.4 parts of 6-(4-methoxyphenyl)-1,3,5-triazine (trade name: Tinosorb S, manufactured by BASF Japan) and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide ( Brand name: Irgacure 819), having an absorption band at a wavelength of 200 to 450 nm, manufactured by BASF Japan) 0.2 parts were added and stirred to obtain a pressure-sensitive adhesive composition having an ultraviolet absorption function.

The pressure-sensitive adhesive composition having the UV-absorbing function was applied on the film on which the release film was peeled, so that the thickness after forming the pressure-sensitive adhesive layer was 150 μm, and then the release film was bonded to the surface of the pressure-sensitive adhesive composition layer. Then, ultraviolet irradiation was performed under the conditions of illuminance: 6.5 mW/cm<2>, and light quantity: 1500 mJ/cm<2>, the adhesive composition layer was photocured, and the visual recognition side adhesive layer (A-1) was formed.

(Preparation of polarizing film (P-1))

A triacetyl cellulose film with a thickness of 25 µm is bonded to the viewer side of a polarizer made of a 12 µm-thick stretched polyvinyl alcohol film impregnated with iodine using a polyvinyl alcohol-based adhesive, and on the surface of the image display unit side of the polarizer, poly An acrylic film having a thickness of 20 µm was laminated using a vinyl alcohol-based adhesive to obtain a polarizing film (P-1). The polarization degree of the polarizing film was 99.995.

(Production of a polarizing film having an adhesive layer)

The visual recognition side adhesive layer (A-1) was laminated|stacked on the visual recognition side (namely, the surface of a 25-micrometer-thick triacetyl cellulose film) of the said polarizing film (P-1). An image display unit side pressure-sensitive adhesive layer (B-1) is laminated on the image display unit side surface of the polarizing film (P-1) (that is, the surface of an acrylic film having a thickness of 20 µm), and a retardation film (thickness: 56 µm, Material: polycarbonate) and the image display part side adhesive layer (B-2) were laminated|stacked, and the polarizing film which has an adhesive layer was formed. The polarizing film which has the obtained adhesive layer is visual recognition side adhesive layer (A-1)/polarizing film (P-1)/image display part side adhesive layer (B-1)/retardation film/image display part side adhesive layer (B-2) ) had a configuration of

Examples 2 to 10

The polarizing film which has an adhesive layer was formed like Example 1 except having carried out the addition amount of a ultraviolet absorber and having done the thickness after formation of the visual recognition side adhesive layer as having described in Table 1.

Examples 11-13

Except not having formed the retardation film and the image display part side adhesive layer (B-2), it carried out similarly to Examples 1-3, and formed the polarizing film which has an adhesive layer.

Comparative Examples 1 to 4

The polarizing film which has an adhesive layer was formed like Example 11 and 1 except having carried out the kind of used polarizing film as what was described in Table 1, and not having formed the visual recognition side adhesive layer. In addition, a polarizing film (P-2) is as follows.

(Preparation of polarizing film (P-2))

A triacetyl cellulose film having a thickness of 60 μm is bonded to the viewer side of a polarizer made of a 12 μm thick stretched polyvinyl alcohol film impregnated with iodine using a polyvinyl alcohol-based adhesive, and a poly A 40-micrometer-thick triacetyl cellulose film was laminated|stacked using the vinyl alcohol-type adhesive agent, and it was set as the polarizing film (P-2). The polarization degree of the polarizing film was 99.995.

Comparative Examples 5 to 8

A polarizing film having a pressure-sensitive adhesive layer was formed in the same manner as in Examples 11 and 1, except that the type of the acrylic pressure-sensitive adhesive composition for forming the viewer-side pressure-sensitive adhesive layer and the addition amount of the ultraviolet absorber were as described in Table 1.

The following evaluation was performed about the polarizing film which has the obtained adhesive layer and an adhesive layer.

<Polymerization rate>

The release film of the visual recognition side adhesive layer used by the Example and the comparative example was peeled, and only the visual recognition side adhesive layer was mounted on the weighed aluminum petri dish. The weight of (aluminum petri dish + adhesive layer on the visibility side) was measured, and the weight of the adhesive layer before drying was calculated|required. After drying at 130° C. for 2 hours, and after cooling for about 20 minutes at room temperature, the weight of (aluminum petri dish + adhesive) was measured again to determine the weight of the adhesive layer on the visual side after drying. The polymerization rate was calculated|required by the following formula.

<Gel fraction>

About 0.1 g was collected from the visual adhesive layer used in Examples and Comparative Examples, and wrapped with a porous tetrafluoroethylene sheet (trade name: NTF1122, manufactured by Nitto Denko Co., Ltd.) having an average pore diameter of 0.2 μm, then bundled with a kite thread. was measured (Zg), and the weight was taken as the weight before immersion. The weight before immersion is the total weight of the visual adhesive layer (the adhesive layer collected above), the tetrafluoroethylene sheet, and the smoke thread. In addition, the total weight of the tetrafluoroethylene sheet and the smoke was also measured (Yg). Next, the visual adhesive layer was wrapped with a tetrafluoroethylene sheet and bundled with a soft thread (referred to as a “sample”), placed in a 50 mL container filled with ethyl acetate, and left still at 23° C. for 7 days. After that, the sample (after ethyl acetate treatment) is taken out from the container, transferred to an aluminum cup, dried at 130°C for 2 hours in a dryer to remove ethyl acetate, and the weight is measured (Xg) and the weight is immersed. It was set as the weight after. The gel fraction was calculated from the following formula.

Gel fraction (wt%)=(X-Y)/(Z-Y)×100

<Measurement of transmittance and b* value of the visual adhesive layer>

The release film of the visual adhesive layer used in Examples and Comparative Examples was peeled off, and the visual adhesive layer was mounted on a measuring jig and measured with a spectrophotometer (product name: U4100, manufactured by Hitachi High-Technologies Co., Ltd.).

<Residual stress>

30 mm in width and 50 mm in length were cut out from the visual recognition side adhesive layer used by the Example and the comparative example, it was made into cylindrical shape, and the test piece was produced. This was set at 20 mm between chucks, and the test piece was pulled by 60 mm (300%) at a pulling rate of 200 mm/min (80 mm between chucks after tensioning). It was fixed (holding support) for 300 seconds at a position where it was stretched by 60 mm, and the stress value (N) after 300 seconds was measured. Residual stress was calculated|required by the following formula.

Residual stress after 300 seconds = Stress value after 300 seconds (N)/(4 × thickness of test piece/10)

<Optical Reliability>

After bonding both sides of the polarizing film having the pressure-sensitive adhesive layer obtained in Examples and Comparative Examples with glass (trade name: S200200, thickness: 1.3 mm, size: 45 mm × 50 mm, manufactured by Matsunami Glass Kogyo Co., Ltd.), Autoclave treatment (atmospheric pressure: 0.5 MPa, temperature: 50°C) was performed for 15 minutes. About Comparative Examples 1-4, the image display part side adhesive layer on the side of a polarizing film or retardation film, and the said glass were bonded, and the autoclave process similar to the above was performed. Thereafter, it was put under the following various reliability conditions and the transmittance was measured with an ultraviolet-visible near-infrared spectrophotometer (product name: V7100, manufactured by Nippon Bunko Co., Ltd.). The amount of change in transmittance from the initial stage was calculated. It evaluated according to the following evaluation criteria.

(various reliability conditions)

(Condition 1) 85℃×500h

(Condition 2) 60℃, 95% × 500h

(Condition 3) Heat shock (HS) (-40°C to 85°C) x 300 cycles

(Condition 4) Under UV irradiation x 100 h, illuminance: 500 W/cm 2 (300 to 700 nm), environmental temperature: 60 to 65 ° C., environmental humidity: 50%

(Evaluation standard)

(circle): Transmittance change amount is 2.0 % or less.

(triangle|delta): Transmittance change amount is more than 2.0 % and 3.0 % or less.

x: The transmittance|transmittance change amount is more than 3.0 %.

<Adhesive contamination, dimensional accuracy, end appearance>

The polarizing film having the pressure-sensitive adhesive layer obtained in Examples and Comparative Examples was cut with a super cutter to a size of 25 mm x 30 mm. Then, 0.05 mm of 4 sides of the side surface of the cut piece were cut by the end surface processing machine (made by Megaro Technica Co., Ltd.), and it was set as the sample. For adhesive contamination, the side of the sample was visually confirmed to confirm the presence or absence of adhesive contamination. About dimensional accuracy and an edge part external appearance, it observed with the optical microscope, and evaluated by the following evaluation criteria.

(Dimensional precision)

○: within ±0.3 mm

×: more than ±0.3 mm

(end appearance)

○: When there is no stickiness of the end when touched by hand

×: When there is stickiness of the end when touched by hand

In Table 1,

P-1 is a polarizing film (P-1),

P-2 is a polarizing film (P-2),

a-1 is the acrylic pressure-sensitive adhesive composition (a-1) obtained in Production Example 1,

a-2 is the acrylic pressure-sensitive adhesive composition (a-2) obtained in Production Example 2,

B-1 is the image display part side adhesive layer (B-1) obtained in manufacture example 3,

B-2 is the image display part side adhesive layer (B-2) obtained in manufacture example 4,

indicates.

1: Polarizing film having an adhesive layer
2a: visual adhesive layer
2b: image display part side pressure-sensitive adhesive layer
3a: visual side transparent protective film
3b: image display part side transparent protective film
4: Polarizer
5: Polarizing film
6: Cover glass or cover plastic
7: Liquid crystal display (LCD) or organic EL display (OLED)
8a, 8b: adhesive layer
9: sensor layer

Claims (6)

It is a polarizing film which has an adhesive layer used on the visual recognition side rather than an image display part in an image display apparatus,
The polarizing film having the pressure-sensitive adhesive layer has a pressure-sensitive adhesive layer on both surfaces of the polarizing film and the polarizing film,
The polarizing film has a polarizer and a transparent protective film on both sides of the polarizer,
The transmittance of the transparent protective film on the visual side of the polarizer at a wavelength of 380 nm is 6% or more and 17% or less,
The pressure-sensitive adhesive layer on the viewer side of the polarizing film has a UV-absorbing function,
The thickness of the transparent protective film on the visual side of the polarizer is 1 μm or more and 40 μm or less,
The transparent protective film on the visual side of the polarizer is a triacetyl cellulose film,
The polymer forming the transparent protective film on the image display side of the polarizer is an acrylic polymer, a styrenic polymer, a polycarbonate polymer, a polyolefin polymer, a vinyl chloride polymer, an amide polymer, an imide polymer, a sulfone polymer, Polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer and epoxy polymer At least one selected from the group consisting of
The pressure-sensitive adhesive layer on the visual side of the polarizing film contains a (meth)acrylic polymer and a UV absorber, and the content of the UV absorber is 0.1 to 5 parts by weight based on 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer. The polarizing film which has an adhesive layer characterized by the above-mentioned. According to claim 1,
The thickness of the adhesive layer by the side of the visual recognition of the said polarizing film is 2 times or more of the thickness of the adhesive layer by the side of the image display part of the said polarizing film, The polarizing film with an adhesive layer characterized by the above-mentioned. According to claim 1,
The transmittance|permeability of wavelength 380nm is 40 % or less, and the transmittance|permeability of wavelength 400nm is 30 % or more, The polarizing film with an adhesive layer of the adhesive layer by the side of visual recognition of the said polarizing film characterized by the above-mentioned. According to claim 1,
The polarizing film with an adhesive layer characterized by the b* value of the adhesive layer by the side of the visual recognition of the said polarizing film being 3.0 or less. According to claim 1,
It is used for a liquid crystal display device or an organic electroluminescent display, The polarizing film which has an adhesive layer characterized by the above-mentioned. The polarizing film which has an adhesive layer as described in any one of Claims 1-5 was used for the visual recognition side rather than an image display part, The image display apparatus characterized by the above-mentioned.

Images