TWI700521B - Polarizing film with adhesive layer and image display device - Google Patents

Abstract

The object of the present invention is to provide a polarizing film with an adhesive layer, which can solve the problem of yield reduction and can provide sufficient anti-ultraviolet function even if the polarizing film is thin. In addition, the present invention also aims to provide an image display device using the aforementioned polarizing film with an adhesive layer.

In terms of solution, a polarizing film with an adhesive layer is used in an image display device that is closer to the viewing side than the image display. It is characterized in that: the polarizing film with the adhesive layer has a polarizing film and is located in the The adhesive layer on both sides of the polarizing film; the aforementioned polarizing film has a polarizer and a transparent protective film located on both sides of the polarizing member; and the transparent protective film on the viewing side of the aforementioned polarizing member has a transmittance of more than 6% at a wavelength of 380nm And the adhesive layer on the viewing side of the aforementioned polarizing film has ultraviolet absorbing function.

Description

Polarizing film with adhesive layer and image display device Invention field

The present invention relates to a polarizing film with an adhesive layer used in an image display device. In addition, the present invention also relates to an image display device using the aforementioned polarizing film with an adhesive layer. Examples of image display devices include liquid crystal display devices, organic EL (electroluminescence) display devices, PDP (plasma display panels), electronic paper, and the like.

Background of the invention

For liquid crystal display devices and organic EL display devices, in terms of image formation methods, for example, in liquid crystal display devices, polarizing elements must be provided on both sides of the liquid crystal element, and polarizing films are generally attached. Moreover, in addition to polarizing films, display panels such as liquid crystal panels and organic EL panels have gradually begun to use various optical elements in order to improve the display quality of displays.

The polarizing film used in these image display devices generally has a structure in which a polarizer is sandwiched between two protective films, and triacetyl cellulose (TAC) is widely used as the protective film.

In recent years, with the trend of lighter and thinner image display devices, various components used in image display devices have sought to be thinner. The protective film of the polarizing film also strives to be thinner. Once the thickness of the aforementioned protective film becomes thinner, it cannot sufficiently block the ultraviolet rays incident on the image display device. Not only the polarizer, but also various optical components used in the image display device such as liquid crystal panels and organic EL elements are prematurely deteriorated by ultraviolet rays. problem.

系紫外線吸收劑之黏著劑層的黏著片(例如參照專利文獻2)。另，亦知在光學薄膜之單面或兩面設有黏著劑層之黏著型光學薄膜中，可對前述黏著劑層賦予紫外線吸收能(例如參照專利文獻3)。 In order to solve this problem, for example, a transparent double-sided adhesive sheet for image display devices is known, which is arranged between the surface protection panel of the image display device and the viewing side of the liquid crystal module to integrate the two components. The surface adhesive sheet has at least one ultraviolet absorbing layer, and has a light transmittance of 30% or less at a wavelength of 380 nm and a visible light transmittance of 80% or more on the longer wavelength side than the wavelength of 430 nm (for example, refer to Patent Document 1), or It has an acrylic polymer and three acridine

It is an adhesive sheet of an adhesive layer of an ultraviolet absorber (for example, refer to Patent Document 2). In addition, it is also known that in an adhesive type optical film provided with an adhesive layer on one or both sides of the optical film, ultraviolet absorbing energy can be imparted to the adhesive layer (for example, refer to Patent Document 3).

Prior art literature Patent literature

Patent Document 1: JP 2012-211305 A

Patent Document 2: JP 2013-75978 A

Patent Document 3: Japanese Patent No. 4208187

Summary of the invention

In recent years, as described in Patent Documents 1 to 3, it is known that A transparent adhesive with ultraviolet absorbing function is used to bond various components used in an image display device, but at this time, uneven thickness may occur, or there may be problems in terms of deterioration in yield and workability.

Therefore, the purpose of the present invention is to provide a polarizing film with an adhesive layer that can solve the problem of lowering the yield and can provide sufficient UV resistance even if the polarizing film is thin. In addition, the present invention also aims to provide an image display device using the aforementioned polarizing film with an adhesive layer.

In order to solve the aforementioned problems, the inventors of the present invention have found the following polarizing film with an adhesive layer as a result of intensive research and completed the present invention.

That is, the present invention relates to a polarizing film with an adhesive layer, which is used in an image display device that is closer to the viewing side than the image display part, and is characterized in that the polarizing film with the adhesive layer has a polarizing film and a position Adhesive layers on both sides of the polarizing film; the polarizing film has a polarizer and a transparent protective film on both sides of the polarizing member; the transparent protective film on the viewing side of the polarizing member has a transmittance of 6% or more at a wavelength of 380nm And the adhesive layer on the viewing side of the aforementioned polarizing film has ultraviolet absorbing function.

The transparent protective film on the viewing side of the aforementioned polarizer is preferably selected from the group consisting of cellulose triacetate film, acrylic film, polyethylene terephthalate film, and polyolefin film of cyclic or norbornene structure At least one kind of film in the group with a thickness of 40 μm or less.

The thickness of the adhesive layer on the viewing side of the polarizing film is preferably more than twice the thickness of the adhesive layer on the image display side of the polarizing film.

The adhesive layer on the viewing side of the aforementioned polarizing film should preferably have a transmittance of less than 40% at a wavelength of 380nm and a transmittance of more than 30% at a wavelength of 400nm.

The b* value of the adhesive layer on the viewing side of the aforementioned polarizing film is preferably 3.0 or less.

The adhesive layer on the viewing side of the aforementioned polarizing film preferably contains an acrylic polymer as the base polymer.

The polarizing film with an adhesive layer of the present invention is preferably used in a liquid crystal display device or an organic EL display device.

In addition, the present invention relates to an image display device, which is characterized in that the polarizing film with the adhesive layer is used on the viewing side of the image display portion.

The polarizing film with an adhesive layer of the present invention has a structure in which an adhesive layer with ultraviolet absorbing function is laminated on the viewing side of the polarizing film in advance, so it can reduce steps and solve the problem of lower yield, even if the polarizing film is thin It can still provide sufficient UV resistance. In addition, since the image display device of the present invention uses the aforementioned polarizing film with an adhesive layer, it is possible to prevent various optical components used in the image display device such as liquid crystal panels and organic EL elements from deteriorating due to ultraviolet rays.

1‧‧‧Polarizing film with adhesive layer

2a‧‧‧Viewing side adhesive layer

2b‧‧‧Image display side adhesive layer

3a‧‧‧Viewing side transparent protective film

3b‧‧‧Transparent protective film on the image display side

4‧‧‧Polarizer

5‧‧‧Polarizing film

6‧‧‧ Cover glass or cover plastic

7‧‧‧Liquid crystal display device (LCD) or organic EL display device (OLED)

8a, 8b‧‧‧Adhesive layer

9‧‧‧Sensor layer

Fig. 1 is a cross-sectional view schematically showing one embodiment of the polarizing film with an adhesive layer of the present invention.

Fig. 2 is a cross-sectional view schematically showing an embodiment of the image display device of the present invention.

Fig. 3 is a cross-sectional view schematically showing an embodiment of the image display device of the present invention.

FIG. 4 is a cross-sectional view schematically showing an embodiment of the image display device of the present invention.

The form used to implement the invention

1. Polarizing film with adhesive layer

The polarizing film with an adhesive layer of the present invention is used in an image display device that is closer to the viewing side than the image display part, and is characterized in that: the polarizing film with the adhesive layer has a polarizing film and two sides of the polarizing film Adhesive layer; the aforementioned polarizing film has a polarizing member and a transparent protective film located on both sides of the polarizing member; the transparent protective film on the viewing side of the aforementioned polarizing member has a transmittance of more than 6% at a wavelength of 380nm, and the aforementioned polarizing film depends on The adhesive layer on the viewing side has ultraviolet absorbing function.

As shown in Figure 1, the polarizing film 1 with an adhesive layer of the present invention only needs to have a viewing side adhesive layer 2a/viewing side transparent protective film 3a/polarization The light member 4/image display section side transparent protective film 3b/image display section side adhesive layer 2b may have a structure including a retardation film or the like. Specifically, it can be viewing side adhesive layer 2a/ viewing side transparent protective film 3a/polarizer 4/image display section side transparent protective film 3b/image display section side adhesive layer 2b/phase difference film (not shown) )/The structure of the adhesive layer (not shown) on the side of the image display section. The polarizing film 5 is composed of a viewing side transparent protective film 3a/polarizer 4/image display section side transparent protective film 3b. Each layer is described in detail below.

(1) Viewing side adhesive layer

The present invention is characterized in that the adhesive layer on the viewing side of the polarizing film (the viewing side adhesive layer) has an ultraviolet absorbing function. The aforementioned adhesive layer on the viewing side should just have an ultraviolet absorbing function, and its composition is not particularly limited.

For the formation of the aforementioned viewing side adhesive layer, an appropriate adhesive can be used, and there is no particular limitation on the type thereof. Adhesives include rubber adhesives, acrylic adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone Adhesives, polyacrylamide-based adhesives, cellulose-based adhesives, etc. Among these adhesives, acrylic adhesives are preferably used from the viewpoints of good optical transparency, showing moderate adhesion, cohesiveness, and adhesive properties, and excellent weather resistance and heat resistance. The aforementioned acrylic adhesive contains an acrylic polymer as a base polymer.

The viewing side adhesive layer using the aforementioned acrylic adhesive is preferably formed, for example, by subjecting an ultraviolet-curable acrylic adhesive composition to ultraviolet polymerization, which contains (meth)acrylic acid The monomer component of the alkyl ester and/or the partial polymer of the aforementioned monomer component, an ultraviolet absorber, and a photopolymerization initiator (A) having an absorption band with a wavelength of 400 nm or more. The adhesive layer formed by subjecting the aforementioned ultraviolet-curable acrylic adhesive composition to ultraviolet polymerization can also form an object with a thickness of 150 μm or more, and can form an adhesive layer with a relatively wide range of thickness, so it is suitable.

Examples of the aforementioned (meth)acrylic acid alkyl esters include those having a linear or branched alkyl group having 1 to 24 carbon atoms at the end of the ester. The alkyl (meth)acrylate may be used alone or in combination of two or more kinds. As for the alkyl (meth)acrylate means alkyl acrylate and/or alkyl methacrylate, the meaning of (meth) in the present invention is the same.

Examples of the aforementioned alkyl (meth)acrylate include branched alkyl (meth)acrylates having 4 to 9 carbon atoms. The alkyl (meth)acrylate is suitable from the viewpoint of easy balance of adhesive properties. Specifically, for example, n-butyl (meth)acrylate, secondary butyl (meth)acrylate, tertiary butyl (meth)acrylate, isobutyl (meth)acrylate, n-butyl (meth)acrylate Amyl ester, isoamyl (meth)acrylate, isohexyl (meth)acrylate, isoheptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, (Meth) isononyl acrylate etc., these can be used individually by 1 type or in combination of 2 or more types.

In the present invention, with respect to the total amount of monofunctional monomer components forming the (meth)acrylic polymer, the aforementioned alkyl (meth)acrylate having an alkyl group with 1 to 24 carbon atoms at the end of the ester More than 40% by weight is suitable, It is preferably 50% by weight or more, and more preferably 60% by weight or more.

The monomer component may contain a comonomer other than the alkyl (meth)acrylate as a monofunctional monomer component. The comonomer can be used as the remainder of the aforementioned alkyl (meth)acrylate of the monomer component.

、乙烯吡

、乙烯吡咯、乙烯咪唑、乙烯

唑、乙烯嗎福林等具有含氮之雜環的乙烯基系單體等。此外，可列舉含有嗎福林環、哌啶環、吡咯啶環、哌

環等之雜環的(甲基)丙烯醯單體。具體上，可列舉N-丙烯醯嗎福林、N-丙烯醯哌啶、N-甲基丙烯醯哌啶、N-丙烯醯吡咯啶等。前述環狀含氮單體中，又以內醯胺系乙烯基單體為宜。 The comonomer may contain, for example, a cyclic nitrogen-containing monomer. The above-mentioned cyclic nitrogen-containing monomer can be used without particular limitation, 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. The cyclic nitrogen structure preferably has a nitrogen atom in the cyclic structure. Cyclic nitrogen-containing monomers include internal vinyl monomers such as N-vinylpyrrolidone, N-vinyl-ε-caprolactone, methyl vinylpyrrolidone, etc.; vinylpyridine, vinylpiperidine Ketones, vinylpyrimidines, vinylpiper

Vinylpyridine

, Vinylpyrrole, vinylimidazole, ethylene

Vinyl monomers with nitrogen-containing heterocycles, such as azole and vinylmorphine. In addition, it can include moforine ring, piperidine ring, pyrrolidine ring, piperidine ring

Heterocyclic (meth)acrylic monomers such as rings. Specifically, N-acrylophrine, N-acryloyl piperidine, N-methacryloyl piperidine, N-acrylopyrrolidine, and the like can be cited. Among the above-mentioned cyclic nitrogen-containing monomers, the lactam-based vinyl monomers are preferred.

In the present invention, relative to the total amount of the monofunctional monomer components forming the (meth)acrylic polymer, the cyclic nitrogen-containing monomer is preferably 0.5-50% by weight, preferably 0.5-40% by weight, 0.5 ~30% by weight is better.

The monomer component used in the present invention may contain 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 a hydroxyl group can be used without particular limitation. Examples of hydroxyl-containing monomers include (meth)acrylic acid 2-hydroxyethyl Ester, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, (meth) Hydroxyalkyl (meth)acrylates such as 6-hydroxyhexyl acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, etc. ; (4-hydroxymethylcyclohexyl) methyl (meth)acrylate and other hydroxyalkyl cycloalkane (meth)acrylate. Other examples include hydroxyethyl (meth)acrylamide, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. These can be used alone or in combination. Among these, hydroxyalkyl (meth)acrylate is preferred.

In the present invention, relative to the total amount of monofunctional monomer components forming the (meth)acrylic polymer, from the viewpoint of improving the adhesion and cohesion, the hydroxyl-containing monomer is preferably 1% by weight or more. It is preferably at least 2% by weight, and more preferably at least 3% by weight. On the other hand, when the aforementioned hydroxyl-containing monomer is too much, the adhesive layer may become hard and reduce the adhesive force, or the adhesive may become too high in viscosity and gelled. From these viewpoints, it is relatively The total amount of monofunctional monomer components of the acrylic polymer, the aforementioned hydroxyl-containing monomer is preferably 30% by weight or less, preferably 27% by weight or less, and more preferably 25% by weight or less.

In addition, the monomer component forming the (meth)acrylic polymer may contain other functional group-containing monomers as monofunctional monomers, and examples include carboxyl group-containing monomers and monomers having cyclic ether groups.

As the carboxyl 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 a carboxyl group can be used without particular limitation. Examples of carboxyl group-containing monomers include (meth)acrylic acid and (meth)acrylic acid Carboxyethyl, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid, etc., which can be used alone or in combination. Iconic acid and maleic acid can use these anhydrides. Among these, acrylic acid and methacrylic acid are suitable, and acrylic acid is particularly suitable. In addition, carboxyl group-containing monomers may be arbitrarily used in the monomer components used to produce the (meth)acrylic polymer of the present invention, but carboxyl group-containing monomers may not be used.

Monomers with cyclic ether groups can be used without particular limitations, and polymerizable functional groups with unsaturated double bonds such as (meth)acrylic groups or vinyl groups and cyclic ethers such as epoxy groups or oxetane groups can be used. Base. Examples of epoxy-containing monomers include glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate ring Oxypropyl ether and so on. Examples of the oxygen-containing cyclobutanyl monomer include 3-oxetanyl methyl (meth) acrylate, 3-methyl-oxetanyl methyl (meth) acrylate, 3- Ethyl-oxetanyl methyl (meth)acrylate, 3-butyl-oxetanyl methyl (meth)acrylate, 3-hexyl-oxetanyl methyl (Meth)acrylate etc. These can be used alone or in combination.

In the present invention, relative to the total amount of the monofunctional monomer components forming the (meth)acrylic polymer, the aforementioned carboxyl group-containing monomer and cyclic ether group-containing monomer is preferably 30% by weight or less, which is 27%. The weight% or less is preferable, and it is more preferable that it is 25 weight% or less.

Regarding the monomer components forming the (meth)acrylic polymer of the present invention, the comonomer can be exemplified by CH ₂ =C(R ¹ )COOR ² (the foregoing R ¹ represents hydrogen or methyl, and R ² represents carbon (Meth)acrylic acid alkyl ester represented by a substituted alkyl group and a cyclic cycloalkyl group of 1 to 3.

Here, as the substituent of the substituted alkyl group having 1 to 3 carbons in R ² , an aryl group having 3 to 8 carbons or an aryloxy group having 3 to 8 carbons is preferable. The aryl group is not limited, but a phenyl group is preferred.

Examples of such monomers represented by CH ₂ =C(R ¹ )COOR ² include phenoxyethyl (meth)acrylate, benzyl (meth)acrylate, and cyclohexyl (meth)acrylate , 3,3,5-trimethylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, etc. These can be used alone or in combination.

In the present invention, relative to the total amount of monofunctional monomer components forming the (meth)acrylic polymer, the (meth)acrylate represented by CH ₂ =C(R ¹ )COOR ² can be 50% by weight % Or less is used, and is preferably 45% by weight or less, preferably 40% by weight or less, and more preferably 35% by weight or less.

Other comonomers can also use vinyl acetate, vinyl propionate, styrene, α-methylstyrene; (meth)acrylic acid polyethylene glycol, (meth)acrylic acid polypropylene glycol, (meth)acrylic acid Glycol acrylate monomers such as methoxy glycol and (meth) methoxy polypropylene glycol; tetrahydrofurfuryl (meth) acrylate, fluorine (meth) acrylate, polysiloxane (methyl) ) Acrylate-based monomers such as acrylate and 2-methoxyethyl acrylate; amine group-containing monomers, amine group-containing monomers, imine group-containing monomers, N-acrylic mopholin, vinyl Ether monomer etc. In addition, as the comonomer, monomers having a cyclic structure such as terpene (meth)acrylate and dicyclopentane (meth)acrylate can be used.

Further, silane-based monomers containing silicon atoms can be cited. Silane-based monomers include, for example, 3-propenyloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltrimethoxysilane, Ethoxysilane, 8-vinyloctyltrimethicone Alkane, 8-vinyl octyl triethoxysilane, 10-methacryloxydecyl trimethoxysilane, 10-acryloxydecyl trimethoxysilane, 10-methacryloxydecyl trimethoxysilane Ethoxysilane, 10-propylene oxydecyl triethoxysilane, etc.

Among the monomer components forming the (meth)acrylic adhesive of the present invention, in addition to the monofunctional monomers exemplified above, in order to adjust the cohesive force of the adhesive, a multifunctional monomer may be contained as required.

A multifunctional single-system monomer having at least two (meth)acrylic groups or vinyl groups and other polymerizable functional groups with unsaturated double bonds, such as (poly)ethylene glycol di(meth)acrylic acid Esters, (poly)propylene glycol di(meth)acrylate, neopentylglycol di(meth)acrylate, neopentylglycol di(meth)acrylate, neopentylerythritol tri(meth)acrylate, Dineopentaerythritol hexa(meth)acrylate, 1,2-ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,12-dodecane Ester compounds of polyols such as glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, etc., and (meth)acrylic acid; Allyl meth)acrylate, vinyl (meth)acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl di(meth)acrylate, di(meth)acrylate Base) Hexyl acrylate and the like. Among these, trimethylolpropane tri(meth)acrylate, hexanediol di(meth)acrylate, and dineopentaerythritol hexa(meth)acrylate are suitably used. A polyfunctional monomer may be used individually by 1 type or in combination of 2 or more types.

The amount of polyfunctional monomer used varies depending on its molecular weight and number of functional groups, etc. However, relative to 100 parts by weight of the total monofunctional monomer, it is 3 Part by weight or less is suitable for use, and preferably 2 parts by weight or less, more preferably 1 part by weight or less. In addition, the lower limit is not particularly limited, but it is preferably 0 part by weight or more, preferably 0.001 part by weight or more. By keeping the usage amount of the multifunctional monomer within the aforementioned range, the adhesive force can be improved.

In the present invention, it may be a partial polymer of the aforementioned monomer components.

系紫外線吸收劑、苯并三唑系紫外線吸收劑、二苯基酮系紫外線吸收劑、氧二苯基酮系紫外線吸收劑、水楊酸酯系紫外線吸收劑、氰基丙烯酸酯系紫外線吸收劑等，該等可單獨使用1種或可將2種以上組合使用。該等中又以三吖

系紫外線吸收劑、苯并三唑系紫外線吸收劑為宜，身為選自於由1分子中具有2個以下羥基之三吖

系紫外線吸收劑以及1分子中具有1個苯并三唑骨架之苯并三唑系紫外線吸收劑所構成群組中之至少1種紫外線吸收劑，對於用來形成紫外線硬化型丙烯酸系黏著劑組成物之單體的溶解性良好，且在波長380nm附近的紫外線吸收能力很高，故為適宜。 The ultraviolet absorber contained in the aforementioned ultraviolet-curable acrylic adhesive composition is not particularly limited, and three are exemplified.

UV absorbers, benzotriazole UV absorbers, benzophenone UV absorbers, oxybenzophenone UV absorbers, salicylate UV absorbers, cyanoacrylate UV absorbers Etc., these can be used individually by 1 type or in combination of 2 or more types. Three acridines

UV absorbers, benzotriazole UV absorbers are suitable, as selected from three acridines having 2 or less hydroxyl groups in one molecule

A UV absorber and at least one UV absorber in the group consisting of a benzotriazole-based UV absorber with a benzotriazole skeleton in one molecule, for the composition used to form a UV-curing acrylic adhesive The monomer of the material has good solubility and high ultraviolet absorption capacity near the wavelength of 380nm, so it is suitable.

系紫外線吸收劑具體上可列舉：2,4-雙-[{4-(4-乙基己基氧基)-4-羥}-苯基]-6-(4-甲氧苯基)-1,3,5-三吖

(Tinosorb S、BASF製)、2,4-雙[2-羥-4-丁氧苯基]-6-(2,4-二丁氧苯基)-1,3,5-三吖

(TINUVIN 460、BASF製)、2-(4,6-雙(2,4-二甲基苯基)-1,3,5-三吖

-2-基)-5-羥苯基與[(C10-C16(主要為C12-C13)烷基 氧基)甲基]環氧乙烷之反應生成物(TINUVIN400、BASF製)、2-[4,6-雙(2,4-二甲基苯基)-1,3,5-三吖

-2-基]-5-[3-(十二烷基氧基)-2-羥丙氧基]酚)、2-(2,4-二羥苯基)-4,6-雙-(2,4-二甲基苯基)-1,3,5-三吖

與(2-乙基己基)-去水甘油酸酯之反應生成物(TINUVIN405、BASF製)、2-(4,6-二苯基-1,3,5-三吖

-2-基)-5-[(己基)氧基]-酚(TINUVIN1577、BASF製)、2-(4,6-二苯基-1,3,5-三吖

-2-基)-5-[2-(2-乙基己醯氧基)乙氧基]-酚(ADK STAB LA46、ADEKA製)、2-(2-羥-4-[1-辛基氧基羰基乙氧基]苯基)-4,6-雙(4-苯基苯基)-1,3,5-三吖

(TINUVIN479、BASF公司製)等。 Three acridines with less than 2 hydroxyl groups in 1 molecule

Specific examples of UV absorbers include: 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1 ,3,5-Three acridine

(Tinosorb S, manufactured by BASF), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triacrine

(TINUVIN 460, manufactured by BASF), 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triacrine

-2-yl)-5-hydroxyphenyl and [(C10-C16 (mainly C12-C13) alkyloxy) methyl] ethylene oxide reaction product (TINUVIN400, BASF product), 2-[ 4,6-bis(2,4-dimethylphenyl)-1,3,5-triacrine

-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), 2-(2,4-dihydroxyphenyl)-4,6-bis-( 2,4-Dimethylphenyl)-1,3,5-Triacrine

Reaction product with (2-ethylhexyl)-dehydrated glycerate (TINUVIN405, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triacrine)

-2-yl)-5-[(hexyl)oxy]-phenol (TINUVIN1577, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triacrine

-2-yl)-5-[2-(2-ethylhexyloxy)ethoxy]-phenol (ADK STAB LA46, manufactured by ADEKA), 2-(2-hydroxy-4-[1-octyl (Oxycarbonylethoxy)phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine

(TINUVIN479, manufactured by BASF Corporation), etc.

In addition, benzotriazole-based ultraviolet absorbers having one benzotriazole skeleton in one molecule include: 2-(2H-benzotriazole-2-yl)-6-(1-methyl-1- Phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN 928, manufactured by BASF), 2-(2-hydroxy-5-tertiarybutylphenyl)-2H -Benzotriazole (manufactured by TINUVIN PS, BASF), phenylpropionic acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy( C7-9 side chain and linear alkyl) ester compound (TINUVIN384-2, BASF made), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1 -Phenylethyl)phenol (TINUVIN900, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1, 1,3,3-Tetramethylbutyl)phenol (TINUVIN928, manufactured by BASF), methyl-3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4- Hydroxyphenyl) propionate/polyethylene glycol 300 reaction product (TINUVIN1130, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-p-cresol (manufactured by TINUVIN P, BASF), 2(2H-benzotriazol-2-yl)-4-6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN234, BASF product), 2-[5-Chloro(2H)-benzotriazol-2-yl]-4-methyl-6-(tertiary butyl)phenol (TINUVIN326, BASF product), 2- (2H-benzotriazol-2-yl)-4,6-di-tertiary amylphenol (TINUVIN328, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-(1 ,1,3,3-Tetramethylbutyl)phenol (TINUVIN329, manufactured by BASF), methyl 3-(3-(2H-benzotriazol-2-yl)-5-tertiary butyl-4- The reaction product of hydroxyphenyl) propionate and polyethylene glycol 300 (TINUVIN213, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methyl Phenol (TINUVIN571, manufactured by BASF), 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimide-methyl)-5-methylphenyl]benzotriazole (Sumisorb250 , Sumitomo Chemical Industries (stocks), etc.

Furthermore, the aforementioned benzophenone-based ultraviolet absorbers (benzophenone-based compounds) and oxybenzophenone-based ultraviolet absorbers (oxybenzophenone-based compounds) can be exemplified by 2,4-dihydroxydiphenyl Ketone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (anhydride and trihydrate), 2-hydroxy-4-octyloxy Benzyl ketone, 4-dodecyloxy-2-hydroxydiphenyl ketone, 4-benzyloxy-2-hydroxydiphenyl ketone, 2,2′,4,4′-tetra Hydroxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzophenone, etc.

In addition, examples of the aforementioned salicylate-based ultraviolet absorbers (salicylate-based compounds) include: phenyl-2-propenyloxy benzoate, phenyl-2-propenyloxy-3-methyl Phenyl benzoate, phenyl-2-propenoxy-4-methyl benzoate, phenyl-2-propenoxy-5-methyl benzoate, phenyl-2-propene Acetyloxy-3-methoxybenzoate, phenyl-2-hydroxybenzoate, phenyl-2-hydroxy-3-methylbenzoate, phenyl-2-hydroxy-4methyl Benzoate, phenyl-2-hydroxy-5-methyl benzoate, phenyl 2-hydroxy-3-methoxybenzoate, 2,4-di -Tributylphenyl-3,5-di-tertiarybutyl-4-hydroxybenzoate (TINUVIN120, manufactured by BASF), etc.

Examples of the aforementioned cyanoacrylate-based ultraviolet absorbers (cyanoacrylate-based compounds) include alkyl-2-cyanoacrylate, cycloalkyl-2-cyanoacrylate, and alkoxyalkyl-2-cyanoacrylate. Alkenyl acrylate, alkenyl-2-cyanoacrylate, alkynyl-2-fluoroacrylate, etc.

The aforementioned ultraviolet absorbers can be used alone or in a mixture of two or more. The total content is 0.1 to 5 parts by weight relative to 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer About 0.5 to 3 parts by weight is preferable. By setting the addition amount of the ultraviolet absorber within the aforementioned range, the ultraviolet absorbing function of the adhesive layer can be fully exerted without hindering ultraviolet polymerization, so it is suitable.

The ultraviolet curable acrylic adhesive composition used in the present invention preferably contains a photopolymerization initiator (A) having an absorption band with a wavelength of 400 nm or more. If UV polymerization is carried out when a UV absorber is contained in the adhesive composition, the UV rays will be absorbed by the above-mentioned UV absorber and cannot be sufficiently polymerized. However, the ultraviolet curable acrylic adhesive composition used in the present invention has a photopolymerization initiator (A) having an absorption band with a wavelength of 400 nm or more, so it can be sufficiently polymerized even if it contains an ultraviolet absorber.

Examples of photopolymerization initiators (A) having an absorption band with a wavelength of 400 nm or more include bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (IRGACURE 819, manufactured by BASF), 2,4 ,6-Trimethylbenzyl-diphenyl-phosphine oxide (LUCIRIN TPO, manufactured by BASF), etc.

Initiation of the aforementioned photopolymerization with an absorption band above 400nm The agent (A) can be used alone or in combination of two or more kinds.

In addition, the addition amount of the photopolymerization initiator (A) having an absorption band with a wavelength of 400 nm or more is not particularly limited, but it is preferably less than the addition amount of the aforementioned ultraviolet absorber, which is relative to the formation of (meth)acrylic polymer 100 parts by weight of the monofunctional monomer component of the material is preferably about 0.005 to 1 part by weight, preferably about 0.02 to 0.5 part by weight. It is suitable to make the addition amount of the photopolymerization initiator (A) within the aforementioned range to allow sufficient ultraviolet polymerization to proceed.

系光聚合引發劑、醯基膦氧化物系光聚合引發劑等。 In addition, the ultraviolet curable acrylic adhesive composition used in the present invention may contain a photopolymerization initiator (B) having an absorption band with a wavelength of 400 nm or less. In addition, the photopolymerization initiator (B) preferably does not have an absorption band with a wavelength of 400 nm or more. The photopolymerization initiator (B) is one that can initiate photopolymerization by generating radicals by ultraviolet rays, and it is not particularly limited as long as it has an absorption band with a wavelength of 400 nm or less, and generally used photopolymerization initiators can be suitably used. For example, benzoin ether-based photopolymerization initiators, acetophenone-based photopolymerization initiators, α-ketol-based photopolymerization initiators, photoactive oxime-based photopolymerization initiators, benzoin-based photopolymerization initiators, Benzyl-based photopolymerization initiator, benzophenone-based photopolymerization initiator, ketal-based photopolymerization initiator, 9-oxysulfur

It is a photopolymerization initiator, an phosphine oxide-based photopolymerization initiator, etc.

Specifically, benzoin ether-based photopolymerization initiators include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, and benzoin isobutyl ether. Ether, 2,2-Dimethoxy-1,2-diphenylethane-1-one, anisole methyl ether, etc.

Examples of acetophenone-based photopolymerization initiators include 2,2-diethoxy Acetophenone, 2,2-Dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl ketone, 4-phenoxydichloroacetophenone, 4-tertiary butyldichlorobenzene Ethyl ketone and so on.

Examples of α-ketol-based photopolymerization initiators include 2-methyl-2-hydroxypropiophenone, 1-[4-(2-hydroxyethyl)phenyl]-2-hydroxy-2-methylpropane-1 -Ketones etc.

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

Examples of the benzoin-based photopolymerization initiator include benzoin.

The benzyl-based photopolymerization initiator includes, for example, benzyl and the like.

The benzophenone-based photopolymerization initiator includes, for example, benzophenone, benzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinyl benzophenone, α -Hydroxycyclohexyl phenyl ketone, etc.

The ketal-based photopolymerization initiator includes benzyl dimethyl ketal and the like.

系光聚合引發劑包含例如9-氧硫

、2-氯9-氧硫

、2-甲基9-氧硫

、2,4-二甲基9-氧硫

、異丙基9-氧硫

、2,4-二氯9-氧硫

、2,4-二乙基9-氧硫

、2,4-二異丙基9-氧硫

、十二烷基9-氧硫

等。 9-oxysulfur

The photopolymerization initiator includes, for example, 9-oxysulfur

, 2-Chloro 9-oxysulfur

, 2-Methyl 9-oxysulfur

, 2,4-Dimethyl 9-oxysulfur

, Isopropyl 9-oxysulfur

, 2,4-Dichloro 9-oxysulfur

, 2,4-Diethyl 9-oxysulfur

, 2,4-Diisopropyl 9-oxysulfur

, Dodecyl 9-oxysulfur

Wait.

Phosphine oxide-based photopolymerization initiators include, for example, 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzyl) -Phenylphosphine oxide, etc.

The aforementioned photopolymerization initiator (B) having an absorption band with a wavelength of 400 nm or less may be used alone or in combination of two or more kinds. The aforementioned photopolymerization initiator (B) having an absorption band with a wavelength below 400 nm can be used without compromising the present invention It is added within the range of effect. In terms of the added amount, it is appropriate to account for about 0.005 to 0.5 parts by weight, accounting for 0.02 to 0.1 parts by weight relative to 100 parts by weight of the monofunctional monomer components forming the (meth)acrylic polymer. The serving size is better.

In the present invention, it is preferable to first add a photopolymerization initiator (B) having an absorption band with a wavelength of 400 nm or less to the aforementioned monomer component, and then to irradiate a part of the polymer (preliminary The polymer composition) is added with the aforementioned photopolymerization initiator (A) having an absorption band with a wavelength of 400 nm or more and an ultraviolet absorber to perform ultraviolet polymerization. When a part of the polymer (prepolymer composition) of a part of the polymerized monomer component is irradiated with ultraviolet rays to add the aforementioned photopolymerization initiator (A) having an absorption band with a wavelength of 400nm or more, it is preferable to dissolve the aforementioned photopolymerization initiator The monomer is added later.

Furthermore, the ultraviolet curable acrylic adhesive composition used in the present invention may contain a silane coupling agent. Relative to 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer, the blending amount of the silane coupling agent is preferably less than 1 part by weight, preferably 0.01 to 1 part by weight, and 0.02 to 0.6 part by weight Better.

The aforementioned silane coupling agent can be exemplified as: 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane , 2-(3,4 epoxycyclohexyl) ethyl trimethoxysilane and other epoxy-containing silane coupling agents; 3-aminopropyl trimethoxysilane, N-2-(aminoethyl)-3-aminopropyl Amino groups such as methyl dimethyl dimethyl siloxane, 3-triethoxy silyl-N-(1,3-dimethylbutylene) propylamine, N-phenyl-γ-aminopropyl trimethoxysilane, etc. The silane coupling agent; 3-propenyloxypropyl trimethoxysilane, 3-methacryloxypropyltriethoxysilane, etc. containing (meth)acrylic acid Coupling agent containing isocyanate groups, such as 3-isocyanate propyl triethoxysilane.

唑啉系交聯劑、吖環丙烷系交聯劑、矽烷系交聯劑、烷基醚化三聚氰胺系交聯劑、金屬螯合物系交聯劑、過氧化物等交聯劑。交聯劑可單獨使用1種或可將2種以上組合使用。該等中，又宜使用異氰酸酯系交聯劑。 The ultraviolet curable acrylic adhesive composition used in the present invention may contain a crosslinking agent. The cross-linking agent includes isocyanate-based cross-linking agents, epoxy-based cross-linking agents, polysiloxane-based cross-linking agents,

Oxazoline-based cross-linking agents, acridine-based cross-linking agents, silane-based cross-linking agents, alkyl etherified melamine-based cross-linking agents, metal chelate-based cross-linking agents, peroxides and other cross-linking agents. A crosslinking agent can be used individually by 1 type or in combination of 2 or more types. Among these, it is also suitable to use an isocyanate-based crosslinking agent.

The aforementioned crosslinking agent can be used alone or in combination of two or more. The total content is 5 parts by weight relative to 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer It is preferably less than 1 part by weight, preferably 0.01 to 5 parts by weight, more preferably 0.01 to 4 parts by weight, and particularly preferably 0.02 to 3 parts by weight.

The isocyanate-based crosslinking agent refers to a compound having two or more isocyanate groups (including isocyanate regeneration type functional groups that temporarily protect the isocyanate groups with a blocking agent or oligomerization) in one molecule. Examples of the isocyanate-based crosslinking agent include aromatic isocyanates such as phenylmethylene diisocyanate and xylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; and aliphatic isocyanates such as hexamethylene diisocyanate.

More specifically, lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; cycloaliphatic isocyanates such as cyclopentyl diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate ; 2,4-Methylphenylene diisocyanate, 4,4'-diphenylmethane Aromatic diisocyanates such as diisocyanate, stubbornyl diisocyanate, polymethylene polyphenyl isocyanate; trimethylolpropane/phenylene diisocyanate trimer adduct (trade name: Coronaate L, Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane/hexamethylene diisocyanate trimer adduct (trade name: Coronaate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.), hexamethylene Isocyanate adducts such as trimeric isocyanate of diisocyanate (trade name: Coronaate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane adducts of diisocyanate (trade name: D110N, Mitsui Chemicals Co., Ltd.), trimethylolpropane adduct of hexamethylene diisocyanate (trade name: D160N, Mitsui Chemicals Co., Ltd.); polyether polyisocyanate, polyester polyisocyanate, and others Adducts with various polyols, trimeric isocyanate bonding, biuret bonding, allophanate bonding, etc. and multifunctional polyisocyanates, etc.

In the ultraviolet curable acrylic adhesive composition used in the present invention, in addition to the aforementioned components, suitable additives may be contained due to application. Examples include tackifiers (for example, solid, semi-solid, or liquid at room temperature composed of rosin derivative resin, polyterpene resin, petroleum resin, oil-soluble phenol resin, etc.); fillers such as hollow glass spheres; Plasticizer; anti-aging agent; antioxidant, etc.

In the present invention, the aforementioned ultraviolet curable acrylic adhesive composition is preferably adjusted to a viscosity suitable for work such as coating on a substrate. The viscosity of the UV-curable acrylic adhesive composition can be adjusted by adding various polymers such as tackifying additives or multifunctional monomers, or It is performed by partially polymerizing the monomer components in the ultraviolet-curable acrylic adhesive composition. As for the partial polymerization, it can be carried out before adding various polymers such as viscosity-increasing additives or polyfunctional monomers, etc., or can be carried out after addition. The viscosity of the above-mentioned ultraviolet-curable acrylic adhesive composition changes according to the additive amount, etc. Therefore, when the monomer components in the ultraviolet-curable acrylic adhesive composition are partially polymerized, the polymerization rate cannot be unambiguously determined, but As far as the measurement standard is concerned, about 20% or less is appropriate, about 3-20% is better, and about 5-15% is better. If the viscosity exceeds 20%, it will become too high and difficult to coat the substrate.

The adhesive layer on the viewing side can be formed by coating the aforementioned ultraviolet-curable acrylic adhesive composition on at least one side of the substrate, and irradiating the ultraviolet-curable acrylic adhesive composition with ultraviolet rays.

The aforementioned substrate is not particularly limited, and various substrates such as a release film, a transparent resin film substrate, or the polarizing film described later are suitable for use as a substrate. When the viewing side adhesive layer is formed on a substrate other than the polarizing film, the viewing side adhesive layer can be attached to the polarizing film for transfer.

The constituent materials of the aforementioned release film include resin films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films, porous materials such as paper, cloth, and non-woven fabrics, nets, and foamed sheets. From the viewpoint of excellent surface smoothness, suitable sheet materials such as metal foils and laminates of these, resin films are suitably used.

The resin film can include, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate Thin ester Film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate copolymer film, etc.

The thickness of the aforementioned release film is usually 5 to 200 μm , and ideally about 5 to 100 μm . The aforementioned release film can also be demoulded and antifouling treated with silicone, fluorine, long-chain alkyl or fatty acid amide based release agents and silica powder, or can be coated Antistatic treatment such as type, kneading type, vapor deposition type, etc. Particularly, by appropriately performing peeling treatments such as silicone treatment, long-chain alkyl treatment, and fluorine treatment on the surface of the release film, the releasability from the adhesive layer can be further improved.

The aforementioned transparent resin film substrate is not particularly limited, and various resin films with transparency can be used. The resin film is formed of a single-layer film. Its materials can include polyester resins such as polyethylene terephthalate and polyethylene naphthalate, acetate resins, polyether turpentine resins, polycarbonate resins, and polyamide resins. , Polyimide resin, polyolefin resin, (meth)acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl alcohol resin, polyarylate Resins, polyphenylene sulfide resins, etc. Among these, polyester-based resins, polyimide-based resins, and polyether sulfide-based resins are particularly preferred.

The thickness of the film substrate is preferably 15 ~ 200 μ m, 25 ~ 188 μ m is preferred.

The method of applying the ultraviolet curable acrylic adhesive composition to the substrate can be roll coating, kiss-roll coating, gravure coating, reverse coating, and roll brushing. , Spraying method, dipping roller coating method, bar coating method, knife coating method, pneumatic knife coating The method, curtain coating method, lip coating method (lip coating), use of a well-known and suitable method such as a die coater is not particularly limited.

The ultraviolet illuminance for irradiating the aforementioned ultraviolet curable acrylic adhesive composition is preferably at least 5 mW/cm ² . When the ultraviolet illuminance is less than 5 mW/cm ² , the polymerization reaction time may increase and productivity may deteriorate. In addition, the ultraviolet illuminance is preferably 200 mW/cm ² or less. If the ultraviolet illuminance exceeds 200 mW/cm ² , the photopolymerization initiator will be rapidly consumed, which will cause the polymer to decrease in molecular weight, and especially the retention at high temperatures may decrease. In addition, the cumulative amount of ultraviolet light is preferably 100mJ/cm ² ~5000mJ/cm ² .

Although the ultraviolet lamp used in the present invention is not particularly limited, an LED lamp is suitable. Compared with other ultraviolet lamps, LED lamps have lower heat emission, so the temperature of the adhesive layer during polymerization can be suppressed. Therefore, the polymer can be prevented from lowering the molecular weight, and the cohesive force of the adhesive layer can be prevented from decreasing, and at the same time, the retention force at high temperature when used as an adhesive sheet can be improved. Also, multiple ultraviolet lamps can be combined. In addition, it is also possible to irradiate ultraviolet rays intermittently, and set the bright period when ultraviolet rays are irradiated and the dark period without ultraviolet rays.

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

In the present invention, the peak wavelength of ultraviolet rays irradiated with the ultraviolet curable acrylic adhesive composition is preferably within a range of 200 to 500 nm, and preferably within a range of 300 to 450 nm. If the peak wavelength of ultraviolet light exceeds 500nm, the photopolymerization initiator may not decompose and cannot initiate polymerization. should. In addition, if the peak wavelength of ultraviolet rays is less than 200 nm, the polymer chain may be cut, which may reduce the bonding characteristics.

The reaction is hindered by oxygen in the air, so in order to isolate oxygen, it is advisable to form a release film on the coating layer of the acrylic adhesive composition, or to perform photopolymerization in a nitrogen environment. Examples of the release film include the aforementioned ones. As for the release film, the release film can be used directly as a separator for the polarizing film attached to the adhesive layer.

From the viewpoint of ensuring the ultraviolet absorbing function, the thickness of the adhesive layer on the viewing side is preferably 2 times or more than the thickness of the adhesive layer on the image display side (image display side adhesive layer) of the polarizing film described later, and 5 times or more. Good, more than 10 times is better. Specifically, the thickness of the aforementioned adhesive layer on the viewing side is preferably 50 μm or more, preferably 100 μm or more, and more preferably 150 μm or more. Although the upper limit of the thickness of the viewing side adhesive layer is not particularly limited, it is preferably 10 mm or less. If the thickness of the adhesive layer exceeds 10mm, the ultraviolet rays may not be easily transmitted, which will make the polymerization of the monomer components more time-consuming and deteriorate the productivity, so it is not suitable.

In addition, when the ultraviolet curable acrylic adhesive composition used in the present invention contains a photopolymerization initiator (B), it is preferable to treat the monomer component containing alkyl (meth)acrylate and the photopolymerization initiator (B). ) (Sometimes also referred to as "pre-added polymerization initiator") after the composition is irradiated with ultraviolet rays to form a partial polymer of the aforementioned monomer component, an ultraviolet absorber and a wavelength of 400 nm or more are added to the partial polymer of the aforementioned monomer component The photopolymerization initiator (A) of the absorption band (sometimes also referred to as "post-addition polymerization initiator") is used to produce an ultraviolet curable acrylic adhesive composition. Polymerization of partial polymers The ratio should be less than 20%, 3~20% is better, and 5~15% is more preferable. The UV irradiation conditions are the same as above.

As mentioned above, when the adhesive layer is formed from the ultraviolet curable acrylic adhesive composition containing the photopolymerization initiator (B), the two-stage polymerization described above can increase the polymerization rate of the monomer components and increase the final production Get the UV absorption function of the adhesive layer.

The gel fraction of the adhesive layer on the viewing side of the present invention is not particularly limited, and is preferably 50% or more, 75% or more, and 85% or more. If the gel fraction of the adhesive layer on the viewing side is very small, the cohesive force is poor. If it is too large, the adhesive force may be poor.

The transmission b* value of the aforementioned adhesive layer on the viewing side is not particularly limited, and is preferably 3.0 or less, 1.5 or less, and more preferably 0.5 or less. The above b* value refers to the b* value (chromaticity) according to the L*a*b* color system in JIS Z8729, for example, it can be measured using a spectrophotometer (product name: U4100, manufactured by Hitachi High-Technologies Corporation) .

The transmittance of the aforementioned adhesive layer on the viewing side at a wavelength of 380 nm is preferably 40% or less, 20% or less is preferable, and 8% or less is more preferable. If the transmittance wavelength at the wavelength of 380nm is within the aforementioned range, the incident ultraviolet rays can be sufficiently blocked, so the deterioration of optical components such as liquid crystal panels, organic EL elements, and polarizers can be suppressed.

The transmittance of the aforementioned adhesive layer on the viewing side at a wavelength of 400 nm is preferably 30% or more, 50% or more, and 70% or more. If the transmittance at a wavelength of 400nm is within the aforementioned range, the incident visible light can be fully transmitted, and sufficient visibility can be ensured in the image display device, so it is suitable should.

(2) Adhesive layer on the image display side

The adhesive layer on the image display side surface of the polarizing film (image display side adhesive layer) is not particularly limited, and the ultraviolet curable acrylic adhesive composition described in detail in the viewing side adhesive layer can be used For the same thing, various commonly used adhesive layers can also be used.

An appropriate adhesive can be used for the formation of the side surface of the image display portion, and there is no particular limitation on the type thereof. Adhesives include rubber adhesives, acrylic adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone Adhesives, polyacrylamide-based adhesives, cellulose-based adhesives, etc. Among these adhesives, acrylic adhesives are preferably used from the viewpoints of good optical transparency, showing moderate adhesion, cohesiveness, and adhesive properties, and excellent weather resistance and heat resistance.

The acrylic adhesive uses an acrylic polymer as a base polymer, and the acrylic polymer uses a monomer unit of alkyl (meth)acrylate as the main skeleton. The alkyl (meth)acrylate that constitutes the main skeleton of the acrylic polymer may be the same as used when forming the ultraviolet curable acrylic adhesive composition of the viewing side adhesive layer. In addition, the comonomer and its ratio can also be exemplified by the same ones used in the ultraviolet curable acrylic adhesive composition.

The aforementioned acrylic polymer can be produced by various known methods. For example, radical polymerization methods such as bulk polymerization, solution polymerization, and suspension polymerization can be appropriately selected. Azo can be used as a radical polymerization initiator Various well-known substances of the series and peroxide series. The reaction temperature is usually about 50 to 80°C, and the reaction time is set to 1 to 8 hours. In addition, among the aforementioned manufacturing methods, the solution polymerization method is suitable, and the solvent for the acrylic polymer is generally ethyl acetate, toluene, etc. The concentration of the solution is usually set at about 20 to 80% by weight.

In addition, the aforementioned adhesive may be an adhesive composition containing a crosslinking agent. The crosslinking agent can also be exemplified above, and isocyanate-based crosslinking agents are particularly preferred. The blending ratio of the acrylic polymer and the crosslinking agent is not particularly limited. Generally, relative to 100 parts by weight of the acrylic polymer (solid content), the crosslinking agent (solid content) should account for about 0.001 to 20 parts by weight, 0.01 ~15 parts by weight is preferred.

In addition, fillers, pigments, colorants, fillers, antioxidants, ultraviolet rays, etc., composed of tackifiers, plasticizers, glass fibers, glass beads, metal powders, other inorganic powders, etc. can be appropriately used in the aforementioned adhesives. Absorbents, silane coupling agents, etc., and various additives can be appropriately used within the scope of the present invention. In addition, an adhesive layer that contains fine particles and exhibits light diffusibility can also be made. Examples of the silane coupling agent include the aforementioned ones.

The adhesive layer on the image display part side can be formed by coating the aforementioned adhesive on various substrates such as a polarizing film or a release film and drying it. When the adhesive layer is formed on various substrates such as a release film, the adhesive layer can be attached to a polarizing film and transferred. The coating method of the aforementioned adhesive and the aforementioned various substrates can be exemplified by the same examples as the coating method of the aforementioned ultraviolet-curable acrylic adhesive composition and various substrates.

In addition, in the aforementioned coating step, the coating amount can be controlled so that the formed adhesive layer has a predetermined thickness (thickness after drying). Although the thickness of the adhesive layer on the image display side is not particularly limited, it is preferably 1/2 or less of the thickness of the adhesive layer on the viewing side, preferably 1/5 or less, and more preferably 1/10 or less. Specifically, the thickness of the adhesive layer on the side of the image display part is preferably about 1-100 μm , preferably about 3-50 μm, and more preferably about 5-30 μm .

The applied adhesive can be dried when forming the adhesive layer on the image display side. The drying temperature and drying time are not particularly limited and can be set appropriately, for example, it is preferably about 80 to 200°C for 0.5 to 10 minutes.

When the adhesive layer on the side of the image display unit is exposed, the release film can protect the adhesive layer until it is used for actual use. In addition, the aforementioned release film can be directly used as a separator for the polarizing film attached to the adhesive layer, and the steps can be simplified.

(3) Polarizing film

The polarizing film used in the present invention is characterized in that it has a polarizer and a transparent protective film on both sides of the polarizer, and the transparent protective film on the viewing side of the polarizing member (transparent protective film on the viewing side) transmits at a wavelength of 380nm The rate is above 6%.

(3-1) Viewing side transparent protective film

The transparent protective film on the viewing side used in the present invention has a transmittance of 6% or more at a wavelength of 380 nm, preferably 10% or more, more preferably 15% or more. The upper limit of the transmittance at a wavelength of 380 nm is not particularly limited, but it is preferably 90% or less, preferably 30% or less. To make the transmittance of the viewing side transparent protective film at a wavelength of 380 nm fall within the aforementioned range, the thinning of the viewing side transparent protective film and the combination of the aforementioned viewing side adhesive layer (including ultraviolet absorption Receiving agent) to achieve sufficient ultraviolet absorption capacity, so it is suitable. Even if the viewing side transparent protective film does not have ultraviolet absorbing ability, it can fully supplement the ultraviolet absorption function by the ultraviolet absorption of the viewing side adhesive layer. Therefore, as long as the transmittance at the aforementioned wavelength of 380nm is below 90%, it has sufficient UV absorption capacity. In addition, when the transmittance of the aforementioned adhesive layer on the viewing side at a wavelength of 380 nm is below 40%, based on the ultraviolet absorption capacity, the transmittance of the viewing side transparent protective film at a wavelength of 380 nm is preferably below 30%.

The material forming the transparent protective film on the viewing side should have excellent transparency, mechanical strength, thermal stability, moisture barrier, and isotropy. Examples include polyester-based polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulosic polymers such as diacetyl cellulose and triacetyl cellulose, polymethylmethacrylate Acrylic polymers such as esters, styrene polymers such as polystyrene and acrylonitrile-styrene copolymer (AS resin), polycarbonate polymers, etc. In addition, examples of polymers forming the aforementioned transparent protective film can also include: such as polyethylene, polypropylene, cyclic or norbornene-based polyolefins, polyolefin-based polymers of ethylene-propylene copolymers, and vinyl chloride-based polymers. Polymers, nylon or aromatic polyamides and other amide-based polymers, imine-based polymers, tungsten-based polymers, polyether ether-based polymers, polyetheretherketone-based polymers, and polyphenylene sulfide-based polymers Polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, aryl ester polymer, polyoxymethylene polymer, epoxy polymer, or the foregoing polymers The mixture and so on. The transparent protective film can also be formed into thermosetting types such as acrylic, urethane, urethane acrylate, epoxy, and silicone And the hardened layer of UV-curable resin. Among them, the viewing side transparent protective film is selected from the group consisting of cellulose triacetate film, acrylic film (film using acrylic polymer), polyethylene terephthalate film and cyclic or norbornene At least one type of film in the group formed by the structured polyolefin film is suitable, and cellulose triacetate film is preferred.

Although the thickness of the transparent protective film on the viewing side is not particularly limited, it is preferably 40 μm or less, preferably 35 μm or less, and more preferably 30 μm or less. In addition, although the lower limit of the thickness of the transparent protective film on the viewing side is not particularly limited, it is preferably 1 μm or more. If the thickness of the transparent protective film on the viewing side is within the aforementioned range, the thinning of the polarizing film can be sufficiently achieved without impairing the protective function of the polarizer, so it is suitable.

The polarizer described later and the protective film on the viewing side should preferably be closely adhered through an aqueous adhesive or the like. Examples of water-based adhesives include isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex systems, water-based polyurethanes, water-based polyesters, and the like. In addition to the above, the adhesive for the polarizer and the transparent protective film on the viewing side can also include ultraviolet curable adhesives and electron beam curable adhesives. The adhesive for electron beam curable polarizing films can exhibit appropriate adhesive properties to the various viewing side transparent protective films described above. In addition, the adhesive used in the present invention may contain a metal compound filler.

For the surface of the transparent protective film on the viewing side that is not attached to the polarizer, hard coating or anti-reflection treatment, or treatment for the purpose of anti-sticking, diffusion and anti-glare can be applied.

(3-2) Polarizing parts

The polarizer is not particularly limited, and various materials can be used. Polarizers can be cited For example, hydrophilic polymer films such as polyvinyl alcohol-based films, partially formalized polyvinyl alcohol-based films, ethylene-vinyl acetate copolymer-based partially saponified films, etc., absorb dichroic substances such as iodine or dichroic dyes and give them a single Shaft stretchers, and polyene-based alignment films such as dehydrated polyvinyl alcohol or dehydrated polyvinyl chloride. Among these, a polarizer made of a dichroic substance such as a polyvinyl alcohol-based film and iodine is suitable. The thickness of the polarizers is not particularly limited, and is generally about 5 to 80 μm.

The polarizing member in which a polyvinyl alcohol-based film is dyed with iodine and uniaxially stretched can be produced by immersing polyvinyl alcohol in an iodine aqueous solution to dye and stretch it to 3 to 7 times its original length. It can be immersed in an aqueous solution such as potassium iodide that may contain boric acid, zinc sulfate, zinc chloride, etc. according to needs. It can also be immersed in water for washing before dyeing. By washing the polyvinyl alcohol-based film with water, the dirt and anti-blocking agent on the surface of the polyvinyl alcohol-based film can be washed away. In addition, it also has the effect of swelling the polyvinyl alcohol-based film to prevent unevenness such as staining. The extension may be performed after dyeing with iodine, the extension may be performed while dyeing, or it may be dyed with iodine after extension. It can also be extended in aqueous solutions such as boric acid or potassium iodide or in a water bath.

Furthermore, in the present invention, a thin polarizer with a thickness of 10 μm or less can also be used. From the viewpoint of thinning, the thickness is preferably 1-7 μm . This thin polarizer has less uneven thickness, good visibility, and less dimensional changes, so it has good durability. Furthermore, the thickness of the polarizing film can be reduced in thickness, which is quite suitable in all aspects.

Representatives of thin polarizers include Japanese Patent Application Publication No. 51-069644, Japanese Patent Application Publication No. 2000-338329, and International Publication No. The thin polarizing film described in the brochure No. 2010/100917, the brochure International Publication No. 2010/100917, or the patent No. 4751481 and the Japanese Patent Laid-Open No. 2012-073563. These thin polarizing films can be produced by a manufacturing method including a step of extending a polyvinyl alcohol-based 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 dyeing step. In this manufacturing method, even if the PVA-based resin layer is thin, it can be extended by the support of the resin base material for stretching, and it will not be broken due to stretching.

In the manufacturing method including the stretching step and the dyeing step in the state of a layered body, the high-magnification stretching and the improvement of the polarization performance are also possible. The aforementioned thin polarizing film is as described in International Publication No. 2010/100917 Manual or Patent No. 4751481 , Japanese Unexamined Patent Application Publication No. 2012-073563 describes that it is preferably obtained by a manufacturing method including a step of extending in an aqueous solution of boric acid, especially as described in Patent No. 4751481 and Japanese Patent Application Publication No. 2012-073563 to be included in It is suitable to be obtained by the method of auxiliary air extension step before extension in boric acid aqueous solution.

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

Regarding the transparent protective film on the image display side, what has been used before can be used appropriately. Specifically, a transparent protective film made of materials with excellent transparency, mechanical strength, thermal stability, moisture barrier properties, and isotropy is suitable, for example: polyethylene terephthalate and polyethylene naphthalate Polyester polymers such as esters, cellulose polymers such as diacetyl cellulose and triacetyl cellulose, acrylic polymers such as polymethyl methacrylate, polystyrene and acrylonitrile-styrene copolymers ( AS resin) and other styrene polymers, polycarbonate Ester-based polymers, etc. In addition, examples of polymers forming the aforementioned transparent protective film can also include: such as polyethylene, polypropylene, cyclic or norbornene-based polyolefins, polyolefin-based polymers of ethylene-propylene copolymers, and vinyl chloride-based polymers. Polymers, nylon or aromatic polyamides and other amide-based polymers, imine-based polymers, tungsten-based polymers, polyether ether-based polymers, polyetheretherketone-based polymers, and polyphenylene sulfide-based polymers Polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, aryl ester polymer, polyoxymethylene polymer, epoxy polymer, or the foregoing polymers The mixture and so on. The transparent protective film can also be formed as a cured layer of thermosetting and ultraviolet curing resins such as acrylic, urethane, urethane acrylate, epoxy, and silicone.

The thickness of the protective film on the side of the image display section can be appropriately determined. Generally, it is about 1 to 500 μm from the viewpoint of workability such as strength and handling properties, and film properties.

The aforementioned polarizer and the transparent protective film on the side of the image display unit are usually adhered to each other through the water-based adhesive or the like. The aforementioned water-based adhesives can be cited.

For the surface of the transparent protective film on the side of the image display section that is not adhered to the polarizer, hard coating or anti-reflection treatment, or treatment for the purpose of anti-sticking, diffusion and anti-glare can be applied.

2. Image display device

In addition, the image display device of the present invention is characterized by using the polarizing film with an adhesive layer of the present invention.

For an example of the specific structure of the image display device, for example, as shown As shown in Figure 2~4, the following image display devices are laminated in order: cover glass or cover plastic 6/viewing side adhesive layer 2a/viewing side transparent protective film 3a/polarizing member 4/image display section Side transparent protective film 3b/Image display part side adhesive layer 2b/Liquid crystal display (LCD) or organic EL display (OLED) 7 (Figure 2); cover glass or cover plastic 6/adhesive layer 8a/sensor Layer 9/Viewing side adhesive layer 2a/Viewing side transparent protective film 3a/Polarizer 4/Image display section side transparent protective film 3b/Image display section side adhesive layer 2b/Liquid crystal display device (LCD) or organic EL Display device (OLED) 7 (Figure 3); cover glass or cover plastic 6/adhesive layer 8a/sensor layer 9/adhesive layer 8b/sensor layer 9/viewing side adhesive layer 2a/viewing Side transparent protective film 3a/polarizer 4/image display section side transparent protective film 3b/image display section side adhesive layer 2b/liquid crystal display device (LCD) or organic EL display device (OLED) 7 (Figure 4).

The polarizing film 1 with an adhesive layer of the present invention means "viewing side adhesive layer 2a/viewing side transparent protective film 3a/polarizer 4/image display section side transparent protective film 3b/image display section side in the aforementioned configuration The part of the adhesive layer 2b" may have a retardation film other than these. In addition, when a retardation film is provided, specifically, the adhesive layer 2b on the side of the image display portion and the liquid crystal display device (LCD) or the organic EL display device (OLED) 7 can be laminated through the adhesive layer. In addition, an adhesive layer and/or an adhesive layer can be suitably used for the build-up of each layer.

Image display devices include liquid crystal display devices, organic EL (electric Electroluminescence) display devices, PDP (plasma display panels), electronic paper, etc., among which liquid crystal display devices and organic EL (electroluminescence) display devices having the aforementioned configuration are suitable.

Example

Hereinafter, the present invention will be specifically described with examples, but the present invention is not limited by these examples. As for the parts and% in each case, all are based on weight. The evaluation items of the examples etc. were measured in the following manner.

Production Example 1 (Production of acrylic adhesive composition (a-1))

A monomer mixture composed of 78 parts by weight of 2-ethylhexyl acrylate (2EHA), 18 parts by weight of N-vinyl-2-pyrrolidone (NVP) and 4 parts by weight of 2-hydroxyethyl acrylate (HEA) As a photopolymerization initiator, 1-hydroxycyclohexyl phenyl ketone (trade name: IRGACURE 184, absorption band with a wavelength of 200 to 370 nm, made by BASF) 0.035 parts by weight, 2,2-dimethoxy-1, After 0.035 parts by weight of 2-diphenylethane-1-one (trade name: IRGACURE 651, absorption band with a wavelength of 200 to 380 nm, manufactured by BASF), irradiated with ultraviolet rays until the viscosity (measurement condition: BH viscometer No. 5) Rotor, 10rpm, measuring temperature 30℃) becomes about 20Pa. s to obtain a prepolymer composition (polymerization rate: 8%) in which part of the above-mentioned monomer components have been polymerized. Next, 0.15 parts by weight of hexanediol diacrylate (HDDA) and 0.3 parts by weight of silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) were added and mixed to the prepolymer composition to obtain acrylic Adhesive composition (a-1).

Production Example 2 (Production of acrylic adhesive composition (a-2))

Mix 67 parts by weight of butyl acrylate (BA) and 14 parts by weight of cyclohexyl acrylate (CHA) Parts by weight, 27 parts by weight of 4-hydroxybutyl acrylate (4HBA), 2,2-dimethoxy-1,2-diphenyl-1-one as a photopolymerization initiator (trade name: IRGACURE 651, with Absorption band with a wavelength of 200~380nm, made by BASF Japan) 0.05 parts by weight and 1-hydroxy-cyclohexyl-phenyl-ketone (trade name: IRGACURE 184, with an absorption band with a wavelength of 200~370nm, made by BASF Japan) 0.05 Parts by weight were put into a 4-necked flask and exposed to ultraviolet rays under a nitrogen atmosphere to perform partial photopolymerization to obtain a partial polymer (monomer slurry) with a polymerization rate of 10%. Next, 0.15 parts by weight of pentaerythritol penta and hexaacrylate (DPHA) and 0.3 parts by weight of silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) were added and mixed to this part of the polymer and irradiated The acrylic adhesive composition (a-2) was obtained by ultraviolet rays.

Production example 3 (production of adhesive layer (B-1) on the side of the image display section)

Put 95 parts of butyl acrylate, 5 parts of acrylic acid, 0.2 part of azobisisobutyronitrile as a polymerization initiator, and 233 parts of ethyl acetate into a separable flask equipped with a thermometer, a stirrer, a reflux cooling tube and a nitrogen introduction tube, and then pour Nitrogen was introduced, and nitrogen substitution was carried out for about 1 hour while stirring. After that, the flask was heated to 60°C and reacted for 7 hours to obtain an acrylic polymer having a weight average molecular weight (Mw) of 1.1 million.

To the above-mentioned acrylic polymer solution (to make solids divided into 100 parts), trimethylolpropane methylene diisocyanate (trade name: Corona L, manufactured by Nippon Polyurethane Industry (stock)) as an isocyanate-based crosslinking agent was added with 0.8 weight Parts, 0.1 part of silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) to prepare an adhesive composition (solution).

The adhesive composition solution was coated on a separator with a thickness of 38 μm (polyethylene terephthalate film with a peel-off surface treatment) in a way that the thickness of the dried adhesive composition was 12 μm , and the adhesive composition solution was applied at 100 It dried for 3 minutes at ℃ and removed the solvent to obtain an adhesive layer. Thereafter, it was heated at 50°C for 48 hours to perform crosslinking treatment. Hereinafter, this adhesive layer is referred to as "image display part side adhesive layer (B-1)".

Production example 4 (production of adhesive layer (B-2) on the side of the image display section)

The adhesive composition prepared in Production Example 3 was coated on a separator (polyethylene terephthalate film with a release treatment on the surface) with a thickness of 38 μm in a way that the thickness after drying was 15 μm After finishing the solution, it was dried at 100°C for 3 minutes and the solvent was removed to obtain an adhesive layer. Thereafter, it was heated at 50°C for 48 hours to perform crosslinking treatment. Hereinafter, this adhesive layer is referred to as "image display part side adhesive layer (B-2)".

Example 1

(Manufacture of adhesive composition with ultraviolet absorption function)

(商品名：Tinosorb S、BASF Japan公司製)1.4份、雙(2,4,6-三甲基苯甲醯基)-苯基膦氧化物(商品名：IRGACURE 819、具有波長200~450nm之吸收帶、BASF Japan公司製)0.2份並予以攪拌而獲得附紫外線吸收機能之黏著劑組成物。 Add 2,4-bis-[{4-(4-ethylhexyloxy)-4 dissolved in butyl acrylate with a solid content of 15% to the obtained acrylic adhesive composition (a-1) -Hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazer

(Trade name: Tinosorb S, manufactured by BASF Japan) 1.4 parts, bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (trade name: IRGACURE 819, with a wavelength of 200 to 450 nm 0.2 parts of absorption tape, made by BASF Japan) and stirred to obtain an adhesive composition with ultraviolet absorbing function.

The aforementioned adhesive composition with ultraviolet absorbing function is applied to the film on which the release film has been peeled off in such a way that the thickness after the adhesive layer is formed is 150 μm , and then the release film is attached to the adhesive The surface of the agent composition layer. Thereafter, ultraviolet rays were irradiated under the conditions of illuminance: 6.5 mW/cm ² and light quantity: 1500 mJ/cm ^{2 to} light-harden the adhesive composition layer to form the viewing side adhesive layer (A-1).

(Manufacture of polarizing film (P-1))

Use a polyvinyl alcohol-based adhesive on the viewing side of a polarizer composed of a 12 μm thick stretched polyvinyl alcohol film impregnated with iodine to affix a 25 μm thick triacetate cellulose film to the image of the polarizer A polyvinyl alcohol-based adhesive layered acrylic film with a thickness of 20 μm was used on the surface of the display section to form a polarizing film (P-1). The polarization degree of the polarizing film is 99.995.

(Manufacture of polarizing film with adhesive layer)

A viewing side adhesive layer (A-1) is laminated on the viewing side of the aforementioned polarizing film (P-1) (that is, the surface of the 25 μm- thick triacetyl cellulose film). Laminate the image display side adhesive layer (B-1) on the image display side surface of the aforementioned polarizing film (P-1) (that is, the 20 μm thick acrylic film surface), and then laminate the retardation film (thickness: 56 μm) m. Material: polycarbonate) and the adhesive layer (B-2) on the side of the image display section to form a polarizing film with the adhesive layer. The resulting polarizing film with an adhesive layer has a viewing side adhesive layer (A-1)/polarizing film (P-1)/image display section side adhesive layer (B-1)/phase difference film/image display section side The composition of the adhesive layer (B-2).

Examples 2~10

The polarizing film with the adhesive layer was formed in the same manner as in Example 1, except that the addition amount of the ultraviolet absorber and the thickness after the formation of the viewing side adhesive layer were set as described in Table 1.

Examples 11~13

A polarizing film with an adhesive layer was formed in the same manner as in Examples 1 to 3 except that the retardation film and the image display portion side adhesive layer (B-2) were not formed.

Comparative example 1~4

The polarizing film with the adhesive layer was formed in the same manner as in Examples 11 and 1, except that the type of polarizing film used was set as described in Table 1 and the viewing side adhesive layer was not formed. As for the polarizing film (P-2), as described below.

(Manufacture of polarizing film (P-2))

Use a polyvinyl alcohol-based adhesive on the viewing side of a polarizer composed of a 12 μm- thick stretched polyvinyl alcohol film impregnated with iodine to affix a 60 μm -thick cellulose triacetate film to the image of the polarizer On the surface of the display section, a polyvinyl alcohol-based adhesive layered with a thickness of 40 μm triacetyl cellulose film was used to form a polarizing film (P-2). The polarization degree of the polarizing film is 99.995.

Comparative example 5~8

Except that the type of acrylic adhesive composition forming the adhesive layer on the viewing side and the addition amount of the ultraviolet absorber are set as described in Table 1, the polarizing film with the adhesive layer was formed in the same manner as in Examples 11 and 1 .

The following evaluations were performed for the obtained adhesive layer and the polarizing film with the adhesive layer.

<polymerization rate>

The release film of the viewing side adhesive layer used in the examples and comparative examples was peeled off, and only the viewing side adhesive layer was placed on a weighed aluminum dish. Measure the weight of (aluminum dish + adhesive layer on the viewing side) to obtain the weight of the adhesive layer before drying weight. After drying at 130°C for 2 hours, cooling at room temperature for about 20 minutes, the weight of (aluminum dish + adhesive) was measured again, and the weight of the adhesive layer on the viewing side after drying was determined. The polymerization rate was determined by the following calculation formula.

<Gel fraction>

Approximately 0.1 g of the adhesive layer on the viewing side used in the examples and comparative examples was collected and coated on a porous tetrafluoroethylene sheet with an average pore diameter of 0.2 μm (trade name: NTF1122, manufactured by Nitto Denko Corporation) , Bind with kite string, measure the weight (Zg) at this time and make the weight before immersion. As for the weight before immersion, the total weight of the adhesive layer on the viewing side (the adhesive layer adopted above), the tetrafluoroethylene sheet and the kite string. In addition, the total weight (Yg) of the tetrafluoroethylene sheet and the kite string is also measured. Next, place the adhesive layer on the viewing side covered with a tetrafluoroethylene sheet and bound with kite string (called "sample") into a 50 mL container filled with ethyl acetate, and let it stand at 23°C 7 day. Then take out the sample (after ethyl acetate treatment) from the container, move it to an aluminum cup, and dry in a dryer at 130°C for 2 hours. After removing ethyl acetate, measure the weight (Xg) and make the weight immersion After weight. The gel fraction was calculated from the following formula.

Gel fraction (weight%)=(X-Y)/(Z-Y)×100

<Measure the transmittance and b* value of the adhesive layer on the viewing side>

After peeling off the release film of the viewing side adhesive layer used in the examples and comparative examples, the viewing side adhesive layer was mounted on the measuring jig, and the spectrophotometer (product name: U4100, Hitachi High-Technologies Corporation) for measurement.

<Residual stress>

The viewing side adhesive layer used in the Examples and Comparative Examples was cut out to have a width of 30 mm and a length of 50 mm, and the test piece was made into a cylindrical shape. The test piece was set so that the distance between the chucks was 20 mm and stretched at a stretching speed of 200 mm/min by 60 mm (300%) (the distance between the chucks after stretching was 80 mm). After the position was fixed (held) for 300 seconds after stretching by 60 mm, the stress value (N) after 300 seconds was measured. The residual stress is obtained by the following formula.

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

<Optical reliability>

The two sides of the polarizing film with adhesive layer obtained in the Examples and Comparative Examples were laminated with glass (trade name: S200200, thickness: 1.3mm, size: 45mm×50mm, manufactured by Songnang Glass Industry Co., Ltd.), and then applied high pressure Autoclave treatment (air pressure: 0.5MPa, temperature: 50°C) for 15 minutes. Regarding Comparative Examples 1 to 4, after bonding the polarizing film or the image display portion side adhesive layer on the retardation film side to the glass, the same autoclave treatment as described above was performed. Then, 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 JASCO Corporation). Find the amount of change in transmittance from the initial time. Use the following evaluation criteria to evaluate.

(Various reliability conditions)

(Condition 1)85℃×500h

(Condition 2) 60℃, 95%×500h

(Condition 3) Thermal shock (HS) (-40℃~85℃)×300 cycles

(Condition 4) Under UV irradiation ×100h, Illumination: 500W/cm ² (300~700nm), Ambient temperature: 60~65℃, Ambient humidity: 50%

(Assessment criteria)

○: The amount of change in transmittance is 2.0% or less.

△: The change in transmittance exceeds 2.0% and is 3.0% or less.

×: The change in transmittance exceeds 3.0%.

<Paste contamination, dimensional accuracy, end appearance>

The polarizing film with the adhesive layer obtained in the Examples and Comparative Examples was cut into a size of 25mm×30mm with an automatic cutter (Super Cutter). After that, the side surface of the cut piece was cut to 0.05 mm on all four sides with an end surface processing machine (manufactured by MEGAROTECHNICA CO., LTD) to prepare a sample. Regarding paste contamination, visually confirm the side of the sample to confirm whether there is paste contamination. The dimensional accuracy and end appearance were observed with an optical microscope and evaluated based on the following evaluation criteria.

(Dimensional accuracy)

○: Within ±0.3mm

×: more than ±0.3mm

(End appearance)

○: No end stickiness when touched

×: There is stickiness at the end when touched by hand

[Table 1]

In Table 1, P-1 represents the polarizing film (P-1); P-2 represents the polarizing film (P-2); a-1 represents the acrylic adhesive composition (a-1) prepared in Production Example 1. ); a-2 represents the acrylic adhesive composition (a-2) prepared in Manufacturing Example 2; B-1 represents the image display portion side adhesive layer (B-1) prepared in Manufacturing Example 3 ; B-2 represents the image display portion side adhesive layer (B-2) prepared in Manufacturing Example 4.

1‧‧‧Polarizing film with adhesive layer

2a‧‧‧Viewing side adhesive layer

2b‧‧‧Image display side adhesive layer

3a‧‧‧Viewing side transparent protective film

3b‧‧‧Transparent protective film on the image display side

4‧‧‧Polarizer

5‧‧‧Polarizing film

Claims (8)

A polarizing film with an adhesive layer, which is used in an image display device that is closer to the viewing side than the image display part, is characterized in that: the polarizing film with an adhesive layer has a polarizing film and a polarizing film located on both sides of the polarizing film Adhesive layer; the aforementioned polarizing film has a polarizer and a transparent protective film located on both sides of the polarizer; and the transparent protective film on the viewing side of the aforementioned polarizing member has a transmittance of more than 6% at a wavelength of 380 nm, The thickness of the transparent protective film on the viewing side is 40 μm or less, and the adhesive layer on the viewing side of the aforementioned polarizing film has an ultraviolet absorbing function. For example, the polarizing film with an adhesive layer of claim 1, wherein the transparent protective film on the viewing side of the polarizer is selected from cellulose triacetate film, acrylic film, polyethylene terephthalate film and ring It is at least one type of film in the group consisting of polyolefin films with norbornene structure, and the thickness is 40 μm or less. The polarizing film with an adhesive layer of claim 1, wherein the thickness of the adhesive layer on the viewing side of the polarizing film is more than twice the thickness of the adhesive layer on the image display side of the polarizing film. The polarizing film with an adhesive layer of claim 1, wherein the adhesive layer on the viewing side of the polarizing film has a transmittance of 40% or less at a wavelength of 380nm and a transmittance of 30% or more at a wavelength of 400nm. Such as the polarizing film with adhesive layer of claim 1, wherein the b* value of the adhesive layer on the viewing side of the polarizing film is 3.0 or less. The polarizing film with an adhesive layer of claim 1, wherein the adhesive layer on the viewing side of the polarizing film contains an acrylic polymer as a base polymer. Such as the polarizing film with an adhesive layer of any one of claims 1 to 6, which is used in a liquid crystal display device or an organic EL display device. An image display device characterized in that the polarizing film with an adhesive layer as in any one of claims 1 to 7 is used on the viewing side of the image display part.

Images