Polarizing film with adhesive layer, and image display device

Abstract

To provide a polarizing film with an adhesive layer, which can solve a problem of decrease in a yield, can impart a sufficient function of blocking UV rays even when a polarizing film is thin, and can suppress curling, and to provide an image display device using the polarizing film with an adhesive layer.SOLUTION: A polarizing film 1 with an adhesive layer is to be used on a visible side of an image display part in an image display device; and the polarizing film 1 with an adhesive layer includes a polarizing film 5 and adhesive layers 2a, 2b on both surfaces of the polarizing film 5. The polarizing film 5 includes a polarizer 4 and transparent protective films 3a, 3b on both surfaces of the polarizer. The transparent protective film 3a on a visible side of the polarizer 4 has a transmittance of less than 6% at a wavelength of 380 nm; and the adhesive layer 2a on a visible side of the polarizing film 5 has an ultraviolet absorption function.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a polarizing film with a pressure-sensitive adhesive layer for use in an image display device. The present invention also relates to an image display device using the polarizing film with the pressure-sensitive adhesive layer. , liquid crystal display devices, organic EL (electroluminescence) display devices, PDP (plasma display display panels), electronic paper, etc. [Background technology]

[0002] Liquid crystal display devices and organic EL display devices are classified into two types based on their image formation methods: In such devices, it is essential to place polarizing elements on both sides of the liquid crystal cell. In addition, polarized light is used on display panels such as LCD panels and organic EL panels. In addition to films, various optical elements are used to improve the display quality. It is becoming more and more common.

[0003] The polarizing films used in these image display devices generally have a polarizer and two protective films. The protective film is triacetyl cellulose (TAC) ) is widely used.

[0004] In recent years, with the trend towards lighter and thinner image display devices, the components used in image display devices have There is a demand for thinner protective films for polarizing films, and there is also a demand for thinner protective films for polarizing films. When the thickness of the protective film is thin, it is difficult to sufficiently block ultraviolet rays incident on the image display device. This has led to the development of not only polarizers but also liquid crystal panels used in image display devices, There is a problem that ultraviolet rays accelerate the deterioration of various optical components, including electroluminescent devices. It was.

[0005] In order to solve such a problem, for example, a surface protection panel and a liquid crystal display device A double-sided adhesive sheet is placed between the viewing side of the crystal module to integrate the two components. It has at least one ultraviolet absorbing layer and has a light transmittance of 300 nm. % or less, and the visible light transmittance at wavelengths longer than 430 nm is 80% or more. A transparent double-sided adhesive sheet for an image display device (see, for example, Patent Document 1) and an acrylic poly A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer containing a triazine-based ultraviolet absorber is known. (See, for example, Patent Document 2). In addition, a pressure-sensitive adhesive layer is provided on one or both sides of the optical film. In the pressure-sensitive adhesive optical film, the pressure-sensitive adhesive layer can be provided with ultraviolet absorbing ability. This is known (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-211305 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-75978 [Patent Document 3] Patent No. 4208187 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, as described in Patent Documents 1 to 3, transparent adhesives having ultraviolet absorbing properties have been developed. It is known that various members used in an image display device are bonded together using a film. There were issues with uneven thickness, reduced yield, and workability.

[0008] In addition, depending on the application of the polarizing film, a higher ultraviolet absorption function may be required. Specifically, if the product is exposed to ultraviolet light for a long period of time (specifically, about 300 hours), Even when exposed to ultraviolet light with a wide wavelength range, the optical properties do not change. It is required that the polarizing film has a high ultraviolet absorption function. was desired.

[0009] In addition, by thinning the polarizer and protective film of the polarizing film, the resulting polarizing film There was also the problem of curling.

[0010] Therefore, the present invention can solve the problem of reduced yield and provide a polarizing film. Even in thin cases, it can provide high UV protection and prevent curling. Another object of the present invention is to provide a polarizing film with a pressure-sensitive adhesive layer that can suppress the Another object of the present invention is to provide an image display device using the polarizing film with the pressure-sensitive adhesive layer. . [Means for solving the problem]

[0011] As a result of extensive research into solving the above problems, the present inventors have discovered the following polarizing filter with an adhesive layer: This led to the discovery of a new compound, which led to the completion of the present invention.

[0012] That is, the present invention provides an adhesive used on the viewing side of an image display unit in an image display device. A layered polarizing film, The polarizing film with a pressure-sensitive adhesive layer comprises a polarizing film and pressure-sensitive adhesive layers on both sides of the polarizing film. and the polarizing film has a polarizer and transparent protective films on both sides of the polarizer; The transparent protective film on the viewing side of the polarizer has a transmittance of less than 6% at a wavelength of 380 nm. Yes, and The adhesive layer on the viewing side of the polarizing film has an ultraviolet absorbing function. The present invention relates to a polarizing film with an adhesive layer.

[0013] The transparent protective film on the viewing side of the polarizer is a triacetyl cellulose film, an acrylic Polyethylene terephthalate film, and cyclo- or norbornene film At least one film selected from the group consisting of polyolefin films having a structure It is preferable that the film is made of a material having a thickness of 40 μm or less.

[0014] The thickness of the adhesive layer on the viewing side of the polarizing film is It is preferable that the thickness is at least twice the thickness of the adhesive layer.

[0015] the pressure-sensitive adhesive layer on the viewing side of the polarizing film has a transmittance of 9% or less at a wavelength of 380 nm, In addition, it is preferable that the transmittance at a wavelength of 400 nm is 60% or more.

[0016] The pressure-sensitive adhesive layer on the viewing side of the polarizing film preferably has a b* value of 3.0 or less.

[0017] the pressure-sensitive adhesive layer on the viewing side of the polarizing film has a transmittance of 9% or less at a wavelength of 380 nm, In addition, it is preferable that the transmittance at a wavelength of 420 nm is 75% or less.

[0018] The pressure-sensitive adhesive layer on the viewing side of the polarizing film is made of an acrylic polymer as a base polymer. It is preferable that it contains

[0019] The polarizing film with a pressure-sensitive adhesive layer of the present invention can be used in a liquid crystal display device or an organic EL display device. It is preferable that:

[0020] In addition, the present invention provides a polarizing film having a pressure-sensitive adhesive layer according to the present invention, which is used on the viewing side of the image display section. The present invention relates to an image display device characterized by the above. [Effects of the Invention]

[0021] The polarizing film with a pressure-sensitive adhesive layer of the present invention is a polarizing film in which the pressure-sensitive adhesive layer having an ultraviolet absorbing function is The structure is pre-laminated on the visible side of the camera, eliminating the need for processes and reducing yields. Even if the polarizing film is thin, it can still provide high UV protection. The image display device of the present invention can be provided with a function to suppress curling. Since the device uses the polarizing film with the adhesive layer, it is possible to It is possible to suppress the deterioration of various optical components, including liquid crystal panels and organic EL elements, due to ultraviolet rays. This can be done. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a cross-sectional view schematically illustrating one embodiment of a polarizing film with a pressure-sensitive adhesive layer of the present invention. [Figure 2] 1 is a cross-sectional view schematically illustrating an embodiment of an image display device of the present invention. [Figure 3] 1 is a cross-sectional view schematically illustrating an embodiment of an image display device of the present invention. [Figure 4] 1 is a cross-sectional view schematically illustrating an embodiment of an image display device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] 1. Polarized film with adhesive layer The pressure-sensitive adhesive layer-attached polarizing film of the present invention is disposed on the viewing side of the image display unit in an image display device. Used, The polarizing film with a pressure-sensitive adhesive layer comprises a polarizing film and pressure-sensitive adhesive layers on both sides of the polarizing film. and the polarizing film has a polarizer and transparent protective films on both sides of the polarizer; The transparent protective film on the viewing side of the polarizer has a transmittance of less than 6% at a wavelength of 380 nm. Yes, and The pressure-sensitive adhesive layer on the viewing side of the polarizing film is characterized by having an ultraviolet absorbing function.

[0024] As shown in FIG. 1, the polarizing film 1 with a pressure-sensitive adhesive layer of the present invention comprises a viewer-side pressure-sensitive adhesive layer 2a / viewer-side pressure-sensitive adhesive layer 2b. Transparent protective film 3a on the image display side / polarizer 4 / transparent protective film 3b on the image display side / image display section It is sufficient that the structure includes the side adhesive layer 2b, and it may also include a retardation film or the like. Specifically, the visible-side pressure-sensitive adhesive layer 2a / visible-side transparent protective film 3a / polarizer 4 / image Display section side transparent protective film 3b / image display section side adhesive layer 2b / retardation film (not shown) The polarizing film 5 may have a structure such as an adhesive layer on the image display section side (not shown). It is composed of a transparent protective film 3a, a polarizer 4, and a transparent protective film 3b on the image display portion side. Each layer is described in detail below.

[0025] (1) Visible side adhesive layer In the present invention, the pressure-sensitive adhesive layer on the viewing side of the polarizing film (viewing-side pressure-sensitive adhesive layer) is an ultraviolet absorbing layer. The visible-side pressure-sensitive adhesive layer may have an ultraviolet absorbing function. The composition thereof is not particularly limited.

[0026] The visible-side adhesive layer can be formed using an appropriate adhesive. There are no particular limitations. Examples of adhesives include rubber-based adhesives, acrylic-based adhesives, and silicone-based adhesives. adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinyl alcohol adhesives adhesives, polyvinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, cellulose-based adhesives Among these adhesives, those with excellent optical transparency, appropriate adhesion and cohesion are preferred. Acrylic adhesives are preferred because they exhibit adhesive properties and are excellent in weather resistance and heat resistance. The acrylic adhesive (composition) is a polymer based on an acrylic polymer. Contains as a mer.

[0027] The acrylic pressure-sensitive adhesive composition may be, for example, a monomer containing alkyl(meth)acrylate. Partial polymers of the monomer components and / or (meth)acrylic polymers obtained from the monomer components It is preferable that the ink contains a polymer and an ultraviolet absorber.

[0028] (1-1) Partially polymerized monomer components and (meth)acrylic polymers The acrylic pressure-sensitive adhesive composition is a monomer composition containing alkyl (meth)acrylate. a partial polymer of the monomer component and / or a (meth)acrylic polymer obtained from the monomer component include.

[0029] The alkyl (meth)acrylate may be a linear or branched alkyl (meth)acrylate having 1 to 24 carbon atoms. Examples include alkyl (meth)acrylates having an alkyl group at the ester terminal. One type may be used alone or two or more types may be used in combination. The acrylate refers to alkyl acrylate and / or alkyl methacrylate. The word "meta" has the same meaning.

[0030] The alkyl(meth)acrylate may be, for example, the branched alkyl(meth)acrylate having 1 to 9 carbon atoms. A preferred example is alkyl(meth)acrylate. ) Acrylate is preferred because it is easy to balance the adhesive properties. butyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate acrylate, isobutyl (meth)acrylate, n-pentyl (meth)acrylate, iso Pentyl (meth)acrylate, isohexyl (meth)acrylate, isoheptyl (meth)acrylate meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate acrylate, isononyl (meth)acrylate, etc., which may be used alone or in combination of two or more. More than one species can be used in combination.

[0031] In the present invention, the alkyl group having 1 to 24 carbon atoms at the ester terminal is Meth)acrylate is a monofunctional monomer component that forms a (meth)acrylic polymer. Preferably, the content is 40% by weight or more, more preferably 50% by weight or more, based on the total amount. It is more preferably 0% by weight or more.

[0032] The monomer component includes, as a monofunctional monomer component, the alkyl(meth)acrylate. The copolymerizable monomer may contain a copolymerizable monomer other than the copolymerizable monomer. It can be used as the remainder of the alkyl (meth)acrylate in the above.

[0033] The copolymerizable monomer may include, for example, a cyclic nitrogen-containing monomer. The nitrogen-containing monomers include those with unsaturated double bonds such as (meth)acryloyl groups or vinyl groups. Any compound having a polymerizable functional group and a cyclic nitrogen structure can be used without any particular limitation. The cyclic nitrogen structure preferably has a nitrogen atom in the cyclic structure. Examples of the monomers that can be contained include N-vinylpyrrolidone and N-vinyl-ε-caprolactone. vinyl lactam monomers such as vinyl vinyl methyl methylpyrrolidone; vinyl pyridine, vinyl pyridine Peridone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinyl Nitrogen-containing heterocycles such as nylimidazole, vinyloxazole, and vinylmorpholine vinyl monomers, etc. Also, morpholine rings, piperidine rings, pyrrolidine rings, Examples include (meth)acrylic monomers containing a heterocycle such as a piperazine ring. , N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine Among the cyclic nitrogen-containing monomers, lysine, N-acryloylpyrrolidine, etc. are mentioned. Of these, lactam vinyl monomers are preferred.

[0034] In the present invention, the cyclic nitrogen-containing monomer is a monomer that forms a (meth)acrylic polymer. The content of the functional monomer components is preferably 0.5 to 50% by weight, more preferably 0.5 to 50% by weight. The content is more preferably 40% by weight, and even more preferably 0.5 to 30% by weight.

[0035] The monomer components used in the present invention include, as monofunctional monomer components, hydroxyl group-containing The hydroxyl group-containing monomer may include (meth)acryloyl a polymerizable functional group having an unsaturated double bond such as an aryl group or a vinyl group, and a hydroxyl group; There are no particular limitations on the hydroxyl group-containing monomers that can be used. Examples of suitable acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl ( (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxy Dihexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10 -Hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate hydroxyalkyl (meth)acrylates such as acrylate; (4-hydroxymethylcyclohexane hydroxyalkylcycloalkane (meth)acrylates such as hydroxyalkyl (meth)methyl (meth)acrylate Other examples include hydroxyethyl (meth)acrylamide, allyl alkenyl acrylate. Chole, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, Diethylene glycol monovinyl ether, etc. These may be used alone or in combination. Among these, hydroxyalkyl (meth)acrylate is preferred. .

[0036] In the present invention, the hydroxyl group-containing monomer is a (meth)acrylic polymer. 1% by weight based on the total amount of monofunctional monomer components to be formed in order to enhance adhesive strength and cohesive strength It is preferably 2% by weight or more, more preferably 3% by weight or more. On the other hand, if the amount of the hydroxyl group-containing monomer is too large, the adhesive layer The adhesive may harden and lose its adhesive strength. Therefore, the hydroxyl group-containing monomer is preferably a (meth)acrylic acid. The amount of the monofunctional monomer components forming the alkyl polymer is 30% by weight or less. It is preferably 27% by weight or less, more preferably 27% by weight or less, and even more preferably 25% by weight or less.

[0037] The monomer components forming the (meth)acrylic polymer include monofunctional monomers and Other functional group-containing monomers may be contained, for example, carboxyl group-containing monomers. monomers having a cyclic ether group.

[0038] The carboxyl group-containing monomer may be an unsaturated monomer such as a (meth)acryloyl group or a vinyl group. The polymerizable functional group having a monovalent double bond and a carboxyl group are particularly limited. The carboxyl group-containing monomer can be used without any need for a (meth)acrylic acid. Acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate ester, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid, etc. These may be used alone or in combination. Itaconic acid and maleic acid may be used in combination with their anhydrides. Among these, acrylic acid and methacrylic acid are preferred, and particularly Acrylic acid is preferred. The mer component may optionally contain a carboxyl group-containing monomer. The xyl group-containing monomer may not be used.

[0039] Examples of the monomer having a cyclic ether group include a (meth)acryloyl group or a vinyl group. It has a polymerizable functional group having an unsaturated double bond and a ring such as an epoxy group or an oxetane group. There are no particular limitations on the epoxy group-containing monomers that have a methyl ether group. Examples of the acrylates include glycidyl (meth)acrylate and 3,4-epoxycyclohexyl Methyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ester Examples of the oxetane group-containing monomer include 3-oxetanyl Methyl (meth)acrylate, 3-methyl-oxetanylmethyl (meth)acrylate, 3-Ethyl-oxetanylmethyl (meth)acrylate, 3-butyl-oxetanylmethyl methyl (meth)acrylate, 3-hexyl-oxetanylmethyl (meth)acrylate, etc. These may be used alone or in combination.

[0040] In the present invention, the carboxyl group-containing monomer and the cyclic ether group-containing monomer is 30% based on the total amount of monofunctional monomer components forming the (meth)acrylic polymer. % by weight or less, more preferably 27% by weight or less, and even more preferably 25% by weight or less. Preferred.

[0041] The monomer components forming the (meth)acrylic polymer of the present invention include copolymerizable monomers and For example, CH2=C(R 1 )COOR 2 (The above R 1 is hydrogen or a methyl group, R 2 is carbon represents a substituted alkyl group having 1 to 3 carbon atoms, or a cyclic cycloalkyl group. (meth)acrylate.

[0042] where R 2 The substituents of the substituted alkyl group having 1 to 3 carbon atoms are It is preferably an aryl group having 3 to 8 carbon atoms or an aryloxy group having 3 to 8 carbon atoms. The aryl group is not limited, but a phenyl group is preferred.

[0043] Such CH2=C(R 1 )COOR 2 Examples of monomers represented by the formula are phenoxy Ethyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate Acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, Isobol These may be used alone or in combination. .

[0044] In the present invention, the CH2=C(R 1 )COOR 2 (Meth)acrylates represented by 50 times the amount of the monofunctional monomer components forming the (meth)acrylic polymer. % by weight or less, preferably 45% by weight or less, and more preferably 40% by weight or less. It is preferably 35% by weight or less.

[0045] Other copolymerizable monomers include vinyl acetate, vinyl propionate, styrene, α-methyl (meth)acrylate, polyethylene glycol, polypropylene Pyrene glycol, (meth)acrylate methoxyethylene glycol, (meth)acrylic acid Glycol-based acrylic ester monomers such as methoxypolypropylene glycol; Tetrahydrofurfuryl acrylate, fluorine (meth)acrylate, silicone (meth)acrylate p) Acrylate ester monomers such as acrylate and 2-methoxyethyl acrylate Amido group-containing monomers, amino group-containing monomers, imido group-containing monomers, N-acrylo Also usable are copolymerized mono- and di-methylmorpholine, vinyl ether monomers, etc. Examples of mers include terpene (meth)acrylate and dicyclopentanyl (meth)acrylate. Monomers having a cyclic structure such as methyl methyl acrylate can be used.

[0046] Further examples include silane-based monomers containing silicon atoms. Examples of suitable silanes include 3-acryloxypropyltriethoxysilane and vinyltrimethoxysilane. Silane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyl Triethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyl Triethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-a Acryloyloxydecyltrimethoxysilane, 10-Methacryloyloxydecyltriethoxysilane triethoxysilane, 10-acryloyloxydecyltriethoxysilane, and the like.

[0047] The monomer components forming the (meth)acrylic polymer of the present invention include the above-exemplified monofunctional In addition to the functional monomer, a polyfunctional monomer may be used as needed to adjust the cohesive strength of the adhesive. It can contain.

[0048] The polyfunctional monomer has an unsaturated double bond such as a (meth)acryloyl group or a vinyl group. It is a monomer having at least two polymerizable functional groups, for example, (poly)ethylene glycol. Lithium di(meth)acrylate, (poly)propylene glycol di(meth)acrylate Neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate 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, tetramethylolpropane Esters of polyhydric alcohols such as methyltri(meth)acrylate and (meth)acrylic acid Allyl (meth)acrylate, vinyl (meth)acrylate, divinylbenzene Epoxy acrylate, polyester acrylate, urethane acrylate, butyl di(meth)acrylate, hexyl di(meth)acrylate, etc. However, trimethylolpropane tri(meth)acrylate, hexanediol di(meth)acrylate acrylate, dipentaerythritol hexa(meth)acrylate is preferably used. The polyfunctional monomers can be used alone or in combination of two or more. This can be done.

[0049] The amount of polyfunctional monomer used varies depending on the molecular weight, number of functional groups, etc. It is preferable to use it in an amount of 3 parts by weight or less, and 2 parts by weight or less, based on 100 parts by weight of the total of the amines. The lower limit is not particularly limited. However, it is preferably 0 part by weight or more, and more preferably 0.001 part by weight or more. By using the polyfunctional monomer in an amount within the above range, the adhesive strength can be improved. can be done.

[0050] The (meth)acrylic polymer can be produced by a radiation polymerization method such as solution polymerization or ultraviolet (UV) polymerization. Any known production method can be appropriately selected, including various radical polymerization methods such as polymerization, bulk polymerization, emulsion polymerization, and the like. The (meth)acrylic polymer obtained may be a random copolymer, a block copolymer, or A graft copolymer or the like may be used.

[0051] In the present invention, a partial polymer of the above-mentioned monomer component can also be suitably used. .

[0052] When the (meth)acrylic polymer is produced by radical polymerization, the monomer - The polymerization initiator, chain transfer agent, emulsifier, etc. used in radical polymerization are appropriately added to the component. The polymerization initiator, chain transfer agent, emulsion, etc. used in the radical polymerization can be used. The curing agent and the like are not particularly limited and can be selected appropriately. The weight average molecular weight of the polymer can be controlled by the amount of polymerization initiator and chain transfer agent used, and the reaction conditions. The amount of each agent used is adjusted depending on the type of agent.

[0053] For example, in solution polymerization, ethyl acetate, toluene, etc. are used as the polymerization solvent. As a specific example of solution polymerization, the reaction is carried out under a stream of inert gas such as nitrogen. An initiator is added, and the reaction is usually carried out at about 50 to 70°C for about 5 to 30 hours.

[0054] Examples of thermal polymerization initiators used in solution polymerization include 2,2'-azobisisobutyrate. 2,2'-azobis-2-methylbutyronitrile, 2,2'-azobis( 2-methylpropionic acid) dimethyl, 4,4'-azobis-4-cyanovaleric acid, Azobisisovaleronitrile, 2,2'-azobis(2-amidinopropane)dihydrochloride lide, 2,2'-azobis[2-(5-methyl-2-imidazolin-2-yl)propanol] dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate Salt, 2,2'-azobis(N,N'-dimethyleneisobutylamidine), 2,2'-azo Bis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate( Azo initiators such as VA-057 (manufactured by Wako Pure Chemical Industries, Ltd.); potassium persulfate, ammonium persulfate persulfates such as ammonium, di(2-ethylhexyl) peroxydicarbonate, di(4- t-Butylcyclohexyl) peroxydicarbonate, di-sec-butylperoxy Dicarbonate, t-butyl peroxyneodecanoate, t-hexyl peroxypivalate t-butyl peroxypivalate, dilauroyl peroxide, di-n-octadecanoate Noyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexyl Sanoate, di(4-methylbenzoyl) peroxide, dibenzoyl peroxide, t -butylperoxyisobutyrate, 1,1-di(t-hexylperoxy)cyclohexane Peroxide initiators such as butyl peroxide, t-butyl hydroperoxide, and hydrogen peroxide, and persulfates Sodium bisulfite combination, peroxide and sodium ascorbate combination Examples of initiators that can be used include redox initiators that combine a peroxide such as It is not limited to these.

[0055] The polymerization initiators may be used alone or in combination of two or more. The amount is preferably about 1 part by weight or less relative to 100 parts by weight of the total amount of the monomer components, It is more preferably about 0.005 to 1 part by weight, and more preferably about 0.02 to 0.5 parts by weight. It is even more preferable that

[0056] When 2,2'-azobisisobutyronitrile is used as the polymerization initiator, The amount of initiator used should be about 0.2 parts by weight or less per 100 parts by weight of the total amount of monomer components. It is preferable that the amount is about 0.06 to 0.2 parts by weight.

[0057] Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptan, Mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethyl thioglycolate Examples of the chain transfer agent include 2,3-dimercapto-1-propanol and the like. They may be used alone or in combination of two or more kinds, but the total content is about 0.3 parts by weight or less relative to 100 parts by weight of the total amount of the monomer components.

[0058] Examples of emulsifiers used in emulsion polymerization include sodium lauryl sulfate, Ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, polyoxyethylene Polyoxyethylene alkyl phenyl ether ammonium sulfate, polyoxyethylene alkyl phenyl ether sulfate anionic emulsifiers such as sodium carbonate, polyoxyethylene alkyl ethers, polyoxyethylene alkyl ethers, Ethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene Examples of suitable emulsifiers include nonionic emulsifiers such as ethylene-polyoxypropylene block polymers. These emulsifiers may be used alone or in combination of two or more.

[0059] Furthermore, as the reactive emulsifier, a radical polymerizable group such as a propenyl group or an allyl ether group may be used. Specific examples of emulsifiers into which functional groups have been introduced include Aqualon HS-10 and HS-2. 0, KH-10, BC-05, BC-10, BC-20 (all manufactured by Daiichi Kogyo Seiyaku ( The amount of emulsifier used is The amount is preferably 5 parts by weight or less relative to 100 parts by weight of the total amount of the monomer components.

[0060] In addition, when the (meth)acrylic polymer is produced by radiation polymerization, It is produced by polymerizing the monomer component by irradiating it with radiation such as electron beams or ultraviolet (UV) rays. Among these, ultraviolet polymerization is preferred. A new embodiment, ultraviolet polymerization, will now be described.

[0061] When performing UV polymerization, the monomer components are used in order to shorten the polymerization time. Therefore, when ultraviolet polymerization is performed, for example, The monomer component containing the alkyl(meth)acrylate and / or the monomer component a partially polymerized product of the above, an ultraviolet-curable acrylic adhesive composition containing an ultraviolet absorber and a photopolymerization initiator The ultraviolet-curable acrylic resin composition is preferably formed by ultraviolet polymerization. The adhesive layer formed by ultraviolet polymerization of the adhesive composition has a thickness of 150 μm or more. This is preferable because it is possible to form adhesive layers of various thicknesses. stomach.

[0062] The photopolymerization initiator may be a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more. When the pressure-sensitive adhesive composition contains an ultraviolet absorber, the ultraviolet polymerization If this is done, the ultraviolet light will be absorbed by the ultraviolet absorber, and the polymerization will not be sufficient. However, if the photopolymerization initiator (A) has an absorption band at wavelengths of 400 nm or more, This is preferable because it can be sufficiently polymerized despite containing an ultraviolet absorber.

[0063] The photopolymerization initiator (A) having an absorption band at wavelengths of 400 nm or more is, for example, bis(2,4,6 -trimethylbenzoyl)-phenylphosphine oxide (Irgacure 819 , manufactured by BASF), 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxa Examples of suitable acrylic resins include LUCIRIN TPO (manufactured by BASF).

[0064] The photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more may be used alone. Alternatively, two or more types may be used in combination.

[0065] The amount of the photopolymerization initiator (A) having an absorption band at wavelengths of 400 nm or more added is particularly Although not limited thereto, it is preferable that the amount is less than the amount of the ultraviolet absorber to be added, which will be described later. , relative to 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer, The amount is preferably about 0.005 to 1 part by weight, and more preferably about 0.02 to 0.5 parts by weight. When the amount of the photopolymerization initiator (A) added is within the above range, ultraviolet polymerization can be easily carried out. This is preferable because it allows sufficient progress.

[0066] The photopolymerization initiator may include a photopolymerization initiator (B The photopolymerization initiator (B) may contain an absorption band at a wavelength of 400 nm or more. The photopolymerization initiator (B) is preferably a compound that generates radicals by ultraviolet light. It generates light and initiates photopolymerization, and has an absorption band at a wavelength of less than 400 nm. There are no particular limitations on the photopolymerization initiator, and any commonly used photopolymerization initiator can be suitably used. For example, benzoin ether-based photopolymerization initiators, acetophenone-based photopolymerization initiators, α-ketone Toluene-based photopolymerization initiators, photoactive oxime-based photopolymerization initiators, benzoin-based photopolymerization initiators, Benzophenone-based photopolymerization initiators, ketal-based photopolymerization initiators, thio By using a xanthone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, etc. This can be done.

[0067] Specifically, examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl Benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenyl ether Examples thereof include methylethan-1-one and anisole methyl ether.

[0068] Examples of acetophenone-based photopolymerization initiators include 2,2-diethoxyacetophenone. , 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl Phenyl ketone, 4-phenoxydichloroacetophenone, 4-t-butyldichloroacetophenone Fennon et al. can be done.

[0069] Examples of α-ketol-based photopolymerization initiators include 2-methyl-2-hydroxypropiophenone. phenone, 1-[4-(2-hydroxyethyl)phenyl]-2-hydroxy-2-methyl propan-1-one and the like.

[0070] Examples of photoactive oxime-based photopolymerization initiators include 1-phenyl-1,2-propanediol. oxime, and the like.

[0071] Examples of the benzoin-based photopolymerization initiator include benzoin.

[0072] The benzyl-based photopolymerization initiator includes, for example, benzyl.

[0073] Benzophenone-based photopolymerization initiators include, for example, benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, α-hydroxybenzophenone hydroxycyclohexyl phenyl ketone and the like.

[0074] Ketal-based photopolymerization initiators include benzyl dimethyl ketal and the like.

[0075] Thioxanthone-based photopolymerization initiators include, for example, thioxanthone and 2-chlorothioxane. thioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone Xanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2, Examples include 4-diisopropylthioxanthone and dodecylthioxanthone.

[0076] Acylphosphine oxide photopolymerization initiators include, for example, 2,4,6-trimethyl Benzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl) (zoyl)-phenylphosphine oxide, etc.

[0077] The photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm may be used alone or in combination of two or more. The photopolymerization method having an absorption band at a wavelength of less than 400 nm can be used in combination. The initiator (B) can be added in an amount that does not impair the effects of the present invention. For 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer, The amount is preferably about 0.005 to 0.5 parts by weight, and more preferably about 0.02 to 0.1 parts by weight. It is more preferable that:

[0078] In the present invention, when the monomer component is polymerized by ultraviolet light, the monomer component is subjected to ultraviolet light. A photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm is added first, and then ultraviolet light is irradiated. The partially polymerized monomer component (prepolymer composition) was subjected to irradiation with the above wavelength of 400 nm. Add a photopolymerization initiator (A) with an absorption band above m and a UV absorber to polymerize with UV light. It is preferable to use a partially polymerized monomer component (prepolymer) that has been partially polymerized by ultraviolet irradiation. (1) a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more is added to the composition. In this case, it is preferable to add the photopolymerization initiator after dissolving it in the monomer.

[0079] (1-2) UV absorbers The ultraviolet absorber contained in the acrylic pressure-sensitive adhesive composition is not particularly limited, but For example, triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based benzophenone-based UV absorbers, oxybenzophenone-based UV absorbers, salicylate-based UV absorbents, cyanoacrylate-based ultraviolet absorbents, etc., and these may be used alone. Or, two or more of them can be used in combination. Among these, triazine-based ultraviolet The absorber is preferably a benzotriazole-based ultraviolet absorber, and has two hydroxyl groups in one molecule. triazine-based ultraviolet absorbers having one or less benzotriazole skeletons in one molecule; At least one benzotriazole-based ultraviolet absorber selected from the group consisting of The fact that it is an ultraviolet absorber makes it soluble in the monomers used to form the acrylic adhesive composition. It is preferable because it has good decomposition properties and has a high ultraviolet absorption capacity at a wavelength of around 380 nm.

[0080] Specific examples of triazine-based ultraviolet absorbers having two or less hydroxyl groups in one molecule include: 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-dibutoxyphenyl)-1,3,5-triazine (TINUVIN 460, B ASF), 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine (C10-C16 (mainly C12-C1 3) Reaction products with alkyloxy)methyl]oxirane (TINUVIN 400, BA SF), 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine -2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol ), 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl) Reaction products of (2-ethylhexyl)-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 (TINUVIN1 577, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazin-2-yl )-5-[2-(2-ethylhexanoyloxy)ethoxy]-phenol (ADK S TAB LA46, manufactured by ADEKA), 2-(2-hydroxy-4-[1-octyloxy Carbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5 -triazine (TINUVIN479, manufactured by BASF), etc.

[0081] In addition, benzotriazole-based ultraviolet absorbers with one benzotriazole skeleton per molecule The collector is 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1- Phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINU VIN 928, manufactured by BASF), 2-(2-hydroxy-5-tert-butylphenyl )-2H-benzotriazole (TINUVIN PS, manufactured by BASF), benzenepropanol Phosphoric acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl) 4-hydroxy(C7-9 branched and straight chain alkyl) ester compounds (TINU VIN384-2, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4, 6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN900, BA SF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenyl)- (1,1,3,3-tetramethylbutyl)phenol (TINUVI N928, manufactured by BASF), methyl-3-(3-(2H-benzotriazol-2-yl) -5-t-butyl-4-hydroxyphenyl)propionate / polyethylene glycol Reaction product of 300 (TINUVIN1130, manufactured by BASF), 2-(2H-benzotriazole) Azol-2-yl)-p-cresol (TINUVIN P, manufactured by BASF), 2(2H -benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl) Phenol (TINUVIN234, manufactured by BASF), 2-[5-chloro(2H)-benzo[ Triazol-2-yl)-4-methyl-6-(tert-butyl)phenol (TIN UVIN326, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6 -Di-tert-pentylphenol (TINUVIN328, manufactured by BASF), 2-(2 H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl) fluorine phenol (TINUVIN 329, manufactured by BASF), methyl 3-(3-(2H-benzotriazole) Azol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate Reaction product of ethylene glycol 300 with TINUVIN 213 (BASF) ), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (TINUVIN571, manufactured by BASF), 2-[2-hydroxy-3-(3,4,5, 6-tetrahydrophthalimido-methyl)-5-methylphenyl]benzotriazole ( Sumisorb 250 (manufactured by Sumitomo Chemical Co., Ltd.) and the like.

[0082] In addition, the benzophenone-based ultraviolet absorbers (benzophenone-based compounds), oxybenzones, Examples of phenone-based ultraviolet absorbers (oxybenzophenone-based compounds) include 2,4- Dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxybenzophenone 4-Methoxybenzophenone-5-sulfonic acid (anhydrous and trihydrate), 2-hydroxybenzophenone 4-octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone Phenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2',4,4'- Tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzo Phenone and the like can be mentioned.

[0083] The salicylate ester-based ultraviolet absorber (salicylate ester-based compound) may also be For example, phenyl-2-acryloyloxybenzoate, phenyl-2-acryloyl phenyl-2-acryloyloxy-4-methylbenzoate, phenyl-2-acryloyloxy-4-methylbenzoate benzoate, phenyl-2-acryloyloxy-5-methylbenzoate, phenyl- 2-Acryloyloxy-3-methoxybenzoate, phenyl-2-hydroxybenzoate ester, phenyl-2-hydroxy-3-methylbenzoate, phenyl-2-hydroxy phenyl-4-hydroxy-5-methylbenzoate, phenyl-2-hydroxy-5-methylbenzoate, phenyl 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate (TINUVIN12 0, manufactured by BASF).

[0084] Examples of the cyanoacrylate ultraviolet absorber (cyanoacrylate compound) include: For example, alkyl-2-cyanoacrylate, cycloalkyl-2-cyanoacrylate, Alkoxyalkyl-2-cyanoacrylate, alkenyl-2-cyanoacrylate, Alkynyl-2-cyanoacrylate and the like can be mentioned.

[0085] Furthermore, as an ultraviolet absorber, for example, a product name "FDB-001" (Yamada Chemical Co., Ltd.) (manufactured by Hayashibara Co., Ltd.), trade name "SMP-122" (manufactured by Hayashibara Co., Ltd.), azomethine compound (trade name: BON ASORB UA-3911, manufactured by Orient Chemical Industry Co., Ltd.), indole chemicals (product Name: BONASORB UA-3701, manufactured by Orient Chemical Industry Co., Ltd., Disperse se Yellow 54 (trade name: KAYASET YELLOW AG, Nippon Kayaku Co., Ltd. )), quinophthalone compound (trade name: MS YELLOW HD-137, Yamada Chemical Industries, Ltd. (Manufactured by Epson Corporation), Solvent Yellow 93 (PLASTYELLOW 8000 , Arimoto Chemical Industry Co., Ltd.), Solvent Yellow 163 (KP Plast Yellow MK (manufactured by Kiwa Chemical Industry Co., Ltd.) or other dyes can also be used.

[0086] The ultraviolet absorbers may be used alone or in combination of two or more. However, the total content is the monofunctional monomer components that form the (meth)acrylic polymer. The amount is preferably about 0.1 to 5 parts by weight, and more preferably 0.5 to 3 parts by weight, per 100 parts by weight of the component. By setting the amount of the ultraviolet absorber to be added in the above range, the adhesiveness can be improved. In the case of ultraviolet polymerization, the ultraviolet absorbing function of the agent layer can be fully exhibited. This is preferable because it does not interfere with the polymerization.

[0087] (1-3) Silane coupling agent Furthermore, the acrylic pressure-sensitive adhesive composition used in the present invention contains a silane coupling agent. The amount of the silane coupling agent to be added is determined based on the amount of the silane coupling agent to be added to form the (meth)acrylic polymer. It is preferably 1 part by weight or less per 100 parts by weight of the monofunctional monomer component, and 0.0 The amount is more preferably 1 to 1 part by weight, and even more preferably 0.02 to 0.6 parts by weight.

[0088] Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane. Silane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyl Diethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane Epoxy group-containing silane coupling agents such as 3-aminopropyltrimethoxysilane, N -2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-triethoxy Silyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-γ-amine Amino group-containing silane coupling agents such as aminopropyltrimethoxysilane, 3-acrylo 3-Methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, etc. (Meth)acrylic group-containing silane coupling agent, 3-isocyanate propyl triethoxy Examples include silane coupling agents containing an isocyanate group such as silane.

[0089] (1-4) Crosslinking agent The acrylic pressure-sensitive adhesive composition used in the present invention may contain a crosslinking agent. Examples include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, silicone-based crosslinking agents, and oxazolidinyl crosslinking agents. Aziridine-based crosslinking agents, silane-based crosslinking agents, alkyl etherified melamine-based crosslinking agents Crosslinking agents include crosslinking agents such as a metal chelate crosslinking agent and a peroxide. Two or more of these may be used in combination. Among these, isocyanate-based crosslinking agents are preferred. It is commonly used.

[0090] The above crosslinking agents may be used alone or in combination of two or more. The total content of the monofunctional monomer components forming the (meth)acrylic polymer is It is preferably 5 parts by weight or less, and more preferably 0.01 to 5 parts by weight, per 100 parts by weight. It is more preferable that the amount is 0.01 to 4 parts by weight, and even more preferable that the amount is 0.02 to 3 parts by weight. I wish.

[0091] Isocyanate-based crosslinking agents are used to block isocyanate groups (isocyanate groups) Two isocyanate regenerating functional groups (temporarily protected by polymerization, etc.) per molecule The isocyanate crosslinking agent is a compound having the above properties. aromatic isocyanates such as xylene diisocyanate, isophorone diisocyanate, etc. Alicyclic isocyanates, aliphatic isocyanates such as hexamethylene diisocyanate, etc. Examples include:

[0092] More specifically, for example, butylene diisocyanate, hexamethylene diisocyanate lower aliphatic polyisocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, Alicyclic isocyanates such as xylene diisocyanate and isophorone diisocyanate, 2,4-Tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, Aromatic diisocyanates such as silylene diisocyanate and polymethylene polyphenyl isocyanate Cyanates, trimethylolpropane / tolylene diisocyanate trimer adduct (product Name: Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd., trimethylolpropane / hexamethylpropane Methylene diisocyanate trimer adduct (product name: Coronate HL, Nippon Polyurethane Co., Ltd.) Co., Ltd.), hexamethylene diisocyanate isocyanurate (product name: Coronet) Isocyanate adducts such as Polyurethane HX (manufactured by Nippon Polyurethane Industry Co., Ltd.), xylylenediamine Trimethylolpropane adduct of socyanate (trade name: D110N, manufactured by Mitsui Chemicals, Inc.) ), hexamethylene diisocyanate trimethylolpropane adduct (trade name: D16 0N, manufactured by Mitsui Chemicals, Inc.); polyether polyisocyanate, polyester polyisocyanate Anates and their adducts with various polyols, isocyanurate bonds, butylene glycols, Examples include polyisocyanates that are multifunctionalized with sorbate bonds, allophanate bonds, etc. can be done.

[0093] (1-5) Other additives In addition to the above components, the acrylic pressure-sensitive adhesive composition used in the present invention may contain appropriate components depending on the application. Additives may be included, such as tackifiers (e.g., rosin derivative resins, polytetrafluoroethylene). Solid, semi-solid, or non-solid at room temperature, consisting of phenolic resin, petroleum resin, oil-soluble phenolic resin, etc. liquids); fillers such as hollow glass balloons; plasticizers; antioxidants; antioxidants, etc. It can be obtained.

[0094] (1-6) Method for forming visible-side adhesive layer In the present invention, the acrylic pressure-sensitive adhesive composition has a viscosity suitable for application onto a substrate. The viscosity of the acrylic pressure-sensitive adhesive composition can be adjusted by, for example, adding a thickening additive. Addition of various polymers such as additives and polyfunctional monomers, and the addition of mono- The partial polymerization is carried out by partially polymerizing the mer component. This may be carried out before or after adding the seed polymer, polyfunctional monomer, etc. The viscosity of the acrylic adhesive composition varies depending on the amount of additives, etc. The polymerization rate when the monomer components in the agent composition are partially polymerized cannot be uniquely determined. However, as a guideline, it is preferable that it is about 20% or less, and more preferably about 3 to 20%. It is more preferable that the content is about 5 to 15%. If the content exceeds 20%, the viscosity becomes too high. It becomes difficult to apply to the material.

[0095] The visible-side pressure-sensitive adhesive layer is formed by applying the acrylic pressure-sensitive adhesive composition to at least one surface of a substrate. The coating film formed from the acrylic pressure-sensitive adhesive composition is dried, or is irradiated with ultraviolet light or the like. The film can be formed by irradiating the film with active energy rays.

[0096] The substrate is not particularly limited, and examples thereof include a release film, a transparent resin film, and the like. Various substrates such as film substrates and polarizing films described later can also be suitably used as the substrate. When the visible-side pressure-sensitive adhesive layer is formed on a substrate other than a polarizing film, the visible-side pressure-sensitive adhesive layer can be transferred by laminating it onto a polarizing film.

[0097] Examples of the material for the release film include polyethylene, polypropylene, and polyethylene terephthalate. Resin films such as ethylene terephthalate and polyester films, paper, cloth, nonwoven fabrics, etc. Suitable thin sheets such as porous materials, nets, foam sheets, metal foils, and laminates thereof However, a resin film is preferably used because of its excellent surface smoothness. .

[0098] Examples of the resin film include polyethylene film and polypropylene film. , polybutene film, polybutadiene film, polymethylpentene film, polysalt vinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film , polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate Copolymer films and the like are examples.

[0099] The thickness of the release film is usually 5 to 200 μm, preferably about 5 to 100 μm. The release film may contain silicone-based, fluorine-based, long-chain alkyl, or the like, as required. Release and antifouling treatment using silica powder, etc., and coating type, It is also possible to carry out antistatic treatment such as kneading or vapor deposition. By appropriately performing peeling treatment such as silicone treatment, long-chain alkyl treatment, fluorine treatment, etc. on the surface, This can further improve the releasability from the pressure-sensitive adhesive layer.

[0100] The transparent resin film substrate is not particularly limited, but may be any of various resins having transparency. The resin film is formed of a single layer of film. For example, the material may be polyethylene terephthalate, polyethylene naphthalate, or other polyethylene. Ester resin, acetate resin, polyethersulfone resin, polycarbonate resin Resin, polyamide resin, polyimide resin, polyolefin resin, (meth)acrylic resins, polyvinyl chloride resins, polyvinylidene chloride resins, polystyrene resins, poly Vinyl alcohol resin, polyarylate resin, polyphenylene sulfide resin, etc. Among these, polyester resins and polyimide resins are particularly preferred. and polyethersulfone resins.

[0101] The thickness of the film substrate is preferably 15 to 200 μm, and more preferably 25 to 188 μm. It is more preferable that m.

[0102] The acrylic pressure-sensitive adhesive composition can be applied to the substrate by roll coating, Lucoat, gravure coat, reverse coat, roll brush, spray coat, Roll coating, bar coating, knife coating, air knife coating, curtain coating, Any known suitable method such as lip coating or die coating can be used without any particular limitation.

[0103] The visible-side pressure-sensitive adhesive layer is formed by drying a coating film formed from the acrylic pressure-sensitive adhesive composition. In this case, the drying conditions (temperature, time) are not particularly limited. The temperature can be appropriately set depending on the composition, concentration, etc. of the catalyst. For example, the temperature is preferably about 60 to 170°C. The heating time is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, at a temperature of 60 to 150°C.

[0104] The acrylic pressure-sensitive adhesive composition is an ultraviolet-curable acrylic pressure-sensitive adhesive composition, When a coating film formed from an ultraviolet-curable acrylic adhesive composition is irradiated with ultraviolet light, In this case, the irradiance of the ultraviolet light is 5mW / cm 2 It is preferable that the illuminance of the ultraviolet light is 5m or more. W / cm 2 If the polymerization time is less than 1000 ppm, the polymerization reaction time will be long, and productivity may be poor. The irradiance of the ultraviolet light is 200mW / cm 2 It is preferable that the irradiance of the ultraviolet light is 200mW / cm 2 If the polymerization temperature exceeds this limit, the photopolymerization initiator is rapidly consumed, causing the polymer to have a low molecular weight. The holding power may decrease, especially at high temperatures. cm 2 ~5000mJ / cm 2 It is preferable that:

[0105] The ultraviolet lamp used in the present invention is not particularly limited, but an LED lamp is preferred. LED lamps emit less heat than other UV lamps, so they are less viscous. The temperature during polymerization of the adhesive layer can be suppressed, which prevents the polymer from becoming low molecular weight. This prevents the cohesive strength of the adhesive layer from decreasing and also makes it possible to maintain the adhesive sheet at high temperatures. It is also possible to combine multiple UV lamps. In addition, ultraviolet light is irradiated intermittently, and a light period in which ultraviolet light is irradiated and a dark period in which ultraviolet light is not irradiated are separated. It can also be set up.

[0106] In the present invention, the final polymerization of the monomer components in the ultraviolet-curable acrylic pressure-sensitive adhesive composition The ratio is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more.

[0107] In the present invention, the peak of ultraviolet light irradiated onto the ultraviolet-curable acrylic pressure-sensitive adhesive composition is The wavelength is preferably in the range of 200 to 500 nm, and more preferably in the range of 300 to 450 nm. It is more preferable that the peak wavelength of the ultraviolet light is within 500 nm. The agent may not decompose and the polymerization reaction may not start. If it is less than m, the polymer chain may be broken, resulting in a decrease in adhesive properties.

[0108] The reaction is inhibited by oxygen in the air, so to block oxygen, UV-curable acrylic is used. A release film or the like is formed on the coating film formed from the pressure-sensitive adhesive composition, or a photopolymerization reaction is prevented by nitrogen It is preferable to carry out the process under a vacuum atmosphere. When a release film is used, the release film can be used as it is to attach the pressure-sensitive adhesive layer. It can be used as a separator for a polarizing film.

[0109] The ultraviolet-curable acrylic pressure-sensitive adhesive composition used in the present invention contains a photopolymerization initiator (B). When it is contained, the monomer component containing alkyl (meth)acrylate and the photopolymerization initiator are A composition containing initiator (B) (sometimes called a "pre-added polymerization initiator") is irradiated with ultraviolet light. a partial polymer of the monomer component is formed, and the partial polymer of the monomer component is subjected to ultraviolet absorbing treatment. and a photoinitiator (A) having an absorption band of 400 nm or more (post-addition polymerization initiator). An ultraviolet-curable acrylic adhesive composition is prepared by adding a UV-curable acrylic adhesive initiator. The polymerization rate of the partially polymerized product is preferably about 20% or less, and is preferably 3 to 2 The ultraviolet irradiation conditions are as described above. That's right.

[0110] As described above, the ultraviolet-curable acrylic pressure-sensitive adhesive composition containing the photopolymerization initiator (B) When forming the adhesive layer, the two-stage polymerization as described above is carried out to polymerize the monomer components. The adhesive layer can be formed by the above method, and the UV absorption function of the adhesive layer can be improved. It is possible.

[0111] The thickness of the pressure-sensitive adhesive layer on the viewing side is determined from the viewpoint of ensuring the ultraviolet absorbing function. The thickness of the adhesive layer on the image display side of the film (adhesive layer on the image display side) must be at least twice as thick. It is preferable that the ratio is 5 times or more, and more preferable that the ratio is 10 times or more. Specifically, the thickness of the visible-side pressure-sensitive adhesive layer is preferably 50 μm or more, and It is more preferable that the thickness is 0 μm or more, and even more preferable that the thickness is 150 μm or more. There is no particular upper limit to the thickness of the adhesive layer on the receiving side, but it is preferably 10 mm or less. If the thickness of the adhesive layer exceeds 10 mm, it becomes difficult for ultraviolet light to penetrate, and the polymerization of the monomer component This is not preferable because it takes a long time and may result in poor productivity.

[0112] The gel fraction of the pressure-sensitive adhesive layer on the viewing side of the present invention is not particularly limited, but is preferably 35% or more. It is preferable that the ratio is 50% or more, more preferable that the ratio is 75% or more. It is more preferable that the gel fraction of the pressure-sensitive adhesive layer on the viewing side is 85% or more, and particularly preferable that the gel fraction of the pressure-sensitive adhesive layer on the viewing side is 85% or more. If it is too small, the cohesive strength may be poor, and if it is too large, the adhesive strength may be poor.

[0113] The transmission b* value of the pressure-sensitive adhesive layer on the viewing side is not particularly limited, but is preferably 3.0 or less. It is preferably 1.5 or less, and more preferably 0.5 or less. The above b* value is the b* value ( For example, a spectrophotometer (product name: U4100, Hitachi High-Technologies Corporation) Measurement can be performed using a meter (manufactured by ZEISS).

[0114] The pressure-sensitive adhesive layer on the viewing side preferably has a transmittance of 9% or less at a wavelength of 380 nm. It is more preferable that the ratio is 7% or less, and even more preferable that the ratio is 5% or less, and it is still more preferable that the ratio is 3% or less. It is particularly preferable that the transmittance at a wavelength of 380 nm is within the above range. This allows for a higher degree of blocking of incident ultraviolet rays, making it suitable for use in LCD panels, organic EL devices, and other devices. This can significantly suppress deterioration of optical members such as polarizers.

[0115] The transmittance of the pressure-sensitive adhesive layer on the viewing side at a wavelength of 400 nm is preferably 60% or more. It is preferable that the wavelength is 70% or more, and more preferable that the wavelength is 75% or more. When the transmittance at 100 nm is in the above range, the incident visible light is sufficiently transmitted. This is preferable because sufficient visibility can be ensured in the image display device.

[0116] In addition, when the pressure-sensitive adhesive layer-attached polarizing film of the present invention is used in an organic electroluminescent display device (OLED), Preferably, the transmittance of the pressure-sensitive adhesive layer on the viewing side at a wavelength of 420 nm is 75% or less. It is preferably 50% or less, and more preferably 40% or less. When the transmittance at a wavelength of 420 nm is in the above range, it is possible to protect the light emitting element of the OLED. It is preferable from the viewpoint.

[0117] When the visible side pressure-sensitive adhesive layer is exposed, the pressure-sensitive adhesive layer is covered with a release film until it is put into practical use. The release film may be used as it is for protecting the separator of the pressure-sensitive adhesive layer-attached polarizing film. This can be used as a meter, simplifying the process.

[0118] (2) Image display side adhesive layer The adhesive layer on the image display portion side surface of the polarizing film (adhesive layer on the image display portion side) is particularly The adhesive layer may be formed from the same acrylic adhesive composition as described above in detail for the visible-side adhesive layer. Various commonly used adhesive layers may be used.

[0119] The adhesive layer on the image display unit side surface can be formed using any suitable adhesive. There are no particular restrictions on the adhesive. Examples of adhesives include rubber adhesives, acrylic adhesives, silicone adhesives, and the like. Polyvinyl alcohol adhesives, urethane adhesives, vinyl alkyl ether adhesives, Polyvinylpyrrolidone adhesive, polyacrylamide adhesive, cellulose Among these adhesives, those with excellent optical transparency and suitable adhesion are Acrylic adhesives are used because they exhibit cohesive and adhesive properties and are excellent in weather resistance and heat resistance. An agent is preferably used.

[0120] Acrylic adhesives are based on the monomer unit of (meth)acrylic acid alkyl ester. The base polymer is an acrylic polymer with the main structure of an acrylic polymer. The (meth)acrylic acid alkyl ester forming the visible side adhesive layer is Examples of the copolymer include those used in the copolymer-based pressure-sensitive adhesive composition. The monomers and their ratios may be the same as those used in the acrylic pressure-sensitive adhesive composition. It is possible.

[0121] The acrylic polymer can be produced by various known methods, for example, bulk polymerization. Radical polymerization methods such as polymerization, solution polymerization, and suspension polymerization can be appropriately selected. As the reaction agent, various known azo-based and peroxide-based agents can be used. The reaction temperature is usually 50 The temperature is about 100°C to 80°C, and the reaction time is 1 to 8 hours. As a solvent for acrylic polymers, ethyl acetate, toluene, etc. are generally used. The solution concentration is usually about 20 to 80% by weight.

[0122] The pressure-sensitive adhesive may be a pressure-sensitive adhesive composition containing a crosslinking agent. Although the above-mentioned crosslinking agents can be used as the crosslinking agent, isocyanate-based crosslinking agents are particularly preferred. The blending ratio of the acrylic polymer and the crosslinking agent is not particularly limited, but usually, the acrylic polymer ( The amount of crosslinking agent (solid content) is about 0.001 to 20 parts by weight per 100 parts by weight of the solid content. The amount is preferably about 0.01 to 15 parts by weight, and more preferably about 0.01 to 15 parts by weight.

[0123] Furthermore, the adhesive may contain, as required, a tackifier, a plasticizer, glass fiber, glass Fillers made of beads, metal powder, other inorganic powders, etc., pigments, colorants, fillers, antioxidants and the like, as long as it does not deviate from the object of the present invention. Various additives can also be used as appropriate. The silane coupling agent may be any of those mentioned above.

[0124] The pressure-sensitive adhesive layer on the image display section side is formed by applying the pressure-sensitive adhesive composition to a polarizing film, a release film, or the like. The adhesive layer is applied to various substrates such as release films and dried. When the pressure-sensitive adhesive layer is formed as described above, the pressure-sensitive adhesive layer can be transferred by being attached to a polarizing film. The adhesive application method and the various substrates are the same as those of the acrylic adhesive composition application method and the various substrates. The same materials as those for the substrate can be used.

[0125] In the coating step, the adhesive layer is formed to a predetermined thickness (thickness after drying). The thickness of the pressure-sensitive adhesive layer on the image display section side is not particularly limited. However, it is preferable that the thickness is 1 / 2 or less of the thickness of the pressure-sensitive adhesive layer on the visible side, and it is 1 / 5 or less. The thickness of the pressure-sensitive adhesive layer on the image display section side is preferably 1 / 10 or less. Generally, the thickness is preferably about 1 to 100 μm, and more preferably about 3 to 50 μm. A thickness of about 5 to 30 μm is more preferable.

[0126] When forming the image display section side adhesive layer, the applied adhesive is dried. The drying temperature and drying time are not particularly limited and can be set appropriately. For example, The temperature is preferably about 200° C. or less for 0.5 to 10 minutes.

[0127] When the pressure-sensitive adhesive layer on the image display section side is exposed, it is adhered with a release film until it is put to practical use. The release film may be used as it is for the pressure-sensitive adhesive layer-attached polarizing film. This can be used as a separator for the above, which simplifies the manufacturing process.

[0128] (3) Polarizing film The polarizing film used in the present invention has a polarizer and transparent protective films on both sides of the polarizer. The transparent protective film on the viewing side of the polarizer (visual side transparent protective film) The transmittance is characterized by being less than 6%.

[0129] (3-1) Transparent protective film on the viewing side The transmittance of the visible-side transparent protective film used in the present invention at a wavelength of 380 nm is less than 6%. and is preferably 3% or less, more preferably 2% or less, and is preferably 1% or less. In the present invention, the transmittance at a wavelength of 380 nm is more preferably 6%. and the pressure-sensitive adhesive layer (containing an ultraviolet absorber) on the viewing side. By combining these, it is possible to achieve a higher level of ultraviolet absorption capability. In addition, the lower limit of the transmittance of the visible-side transparent protective film at a wavelength of 380 nm is particularly Limited The smaller the size, the better from the viewpoint of ultraviolet absorbing function.

[0130] The material for forming the visible side transparent protective film must have transparency, mechanical strength, thermal stability, and water resistance. Those with excellent polarization blocking properties and isotropy are preferred. For example, polyethylene terephthalate and polyethylene terephthalate are preferred. Polyester polymers such as polyethylene naphthalate, diacetyl cellulose, triacetate, cellulose-based polymers such as ethyl cellulose, acrylic polymers such as polymethyl methacrylate, Styrene such as polymer, polystyrene and acrylonitrile-styrene copolymer (AS resin) Polyethylene, polypropylene, polycarbonate, etc. propylene, polyolefins with cyclo- or norbornene structures, ethylene / propylene Polyolefin polymers such as pyrene copolymers, vinyl chloride polymers, nylon, and aromatic Amide polymers such as aromatic polyamides, imide polymers, sulfone polymers, polyethersulfones, Tersulfone polymers, polyetheretherketone polymers, polyphenylene sulfonates vinyl chloride polymers, vinyl alcohol polymers, vinylidene chloride polymers, vinyl bromide polymers Alkyl polymers, arylate polymers, polyoxymethylene polymers, epoxy The polymer forming the transparent protective film may be a polymer of the same type or a blend of the polymers. Examples of transparent protective films include acrylic, urethane, and acrylic urethane. As a hardening layer for thermosetting and UV-curing resins such as ethane, epoxy, and silicone. Among these, the visible side transparent protective film is preferably triacetyl. cellulose film, acrylic film (film using acrylic polymer), polyethylene terephthalate film and polyolefin film having a cyclo- or norbornene structure At least one film selected from the group consisting of polyolefin films A triacetyl cellulose film is preferred, and a triacetyl cellulose film is more preferred.

[0131] The thickness of the visible-side transparent protective film is not particularly limited, but is preferably 40 μm or less. Preferably, it is 35 μm or less, more preferably 30 μm or less. The lower limit of the thickness of the visible-side transparent protective film is not particularly limited, but is preferably 1 μm or more. When the thickness of the viewer-side transparent protective film is in the above range, the polarizing film This is preferable because it allows the film to be made sufficiently thin and does not impair the protective function of the polarizer. stomach.

[0132] The polarizer and the viewing-side protective film described below are preferably adhered to each other via a water-based adhesive or the like. Water-based adhesives include isocyanate adhesives, polyvinyl alcohol adhesives, Examples include gelatin adhesives, vinyl latex adhesives, water-based polyurethane adhesives, and water-based polyester adhesives. In addition to the above, ultraviolet curing adhesives can be used to bond the polarizer and the visible-side transparent protective film. Electron beam curable adhesives for polarizing films are available. It exhibits suitable adhesiveness to the various transparent protective films on the viewer side. The adhesive may contain a metal compound filler.

[0133] The surface of the viewer-side transparent protective film to which the polarizer is not bonded is provided with a hard coat layer or an anti-reflection layer. Treated for anti-sticking, diffusion or anti-glare purposes It may be.

[0134] (3-2) Polarizer The polarizer is not particularly limited, and various polarizers can be used. Vinyl alcohol film, partially formalized polyvinyl alcohol film, ethyl Hydrophilic polymer films such as partially saponified polyethylene-vinyl acetate copolymer films are treated with iodine or Dichroic dyes are adsorbed onto the material and uniaxially stretched. Polyvinyl alcohol is dehydrated. Examples include polyene-based oriented films such as dehydrochlorinated polyvinyl chloride and polyvinyl chloride. Among these, polarizers made of a polyvinyl alcohol film and a dichroic substance such as iodine are preferred. The thickness of these polarizers is not particularly limited, but is generally about 5 to 80 μm. do.

[0135] A polarizer obtained by dyeing a polyvinyl alcohol film with iodine and stretching it uniaxially is, for example, Polyvinyl alcohol is dyed by immersing it in an aqueous solution of iodine, and the film is stretched to 3 to 7 times its original length. It can be made by stretching. If necessary, it may contain boric acid, zinc sulfate, zinc chloride, etc. It is also possible to immerse the film in an aqueous solution of potassium iodide or the like, which may contain potassium iodide. Before dyeing, the polyvinyl alcohol film may be immersed in water and washed. Washing the polyvinyl alcohol film with water removes dirt and blocks from the surface of the film. In addition to being able to wash away anti-blocking agents, it also helps prevent swelling of polyvinyl alcohol-based films. This also has the effect of preventing unevenness in the dyeing. Alternatively, the film may be stretched while being dyed, or may be dyed with iodine after being stretched. It can be stretched in an aqueous solution of boric acid or potassium iodide, or in a water bath.

[0136] In the present invention, a thin polarizer having a thickness of 10 μm or less can also be used. From the viewpoint of miniaturization, the thickness is preferably 1 to 7 μm. The product has little thickness variation, excellent visibility, and little dimensional change, making it highly durable. Furthermore, it is preferable that the thickness of the polarizing film can be reduced.

[0137] Representative examples of thin polarizers include those disclosed in Japanese Patent Application Laid-Open No. 51-069644 and Japanese Patent Application Laid-Open No. 2000 -338329, International Publication No. 2010 / 100917, International Publication No. 2010 / 100917 pamphlet, or the specification of Patent No. 4751481 or Patent Publication No. 20 Examples of such thin polarizing films include those described in Japanese Patent Application Publication No. 12-073563. The polarizing film is made of a polyvinyl alcohol resin (hereinafter referred to as PVA resin) layer and a stretching resin. It can be obtained by a manufacturing method including a step of stretching the oil base material in a laminated state and a step of dyeing it. With this manufacturing method, even if the PVA resin layer is thin, it is supported by the stretching resin substrate. This allows stretching to be carried out without problems such as breakage due to stretching.

[0138] The thin polarizing film is produced by a method including a step of stretching a laminate and a step of dyeing the laminate. However, in terms of being able to be stretched at a high magnification and improving polarization performance, / 100917 brochure, International Publication No. 2010 / 100917 brochure, As described in the specification of Japanese Patent No. 4751481 and Japanese Patent Laid-Open No. 2012-073563, It is preferable to use a method including a step of stretching in a boric acid aqueous solution. Stretching in an aqueous boric acid solution as described in JP-A-2012-073563 and JP-A-2012-073563 Preferably, the film is obtained by a manufacturing method including a step of auxiliary air-stretching before the film is formed.

[0139] (3-3) Transparent protective film on the image display side Regarding the transparent protective film on the image display side, a conventional one can be used as appropriate. Specifically, it has excellent transparency, mechanical strength, thermal stability, moisture blocking properties, isotropy, etc. A transparent protective film made of a material such as polyethylene terephthalate is preferred. polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, diacetyl cellulose and polyethylene terephthalate; cellulose-based polymers such as triacetyl cellulose, acrylates such as polymethyl methacrylate, Polymers such as styrene, polystyrene, and acrylonitrile-styrene copolymers (AS resins) Examples of the polymer include polyethylene-based polymers and polycarbonate-based polymers. Polypropylene, polyolefins with cyclo- or norbornene structures, ethylene Polyolefin polymers such as propylene copolymers, vinyl chloride polymers, nylon and aromatic polyamides and other amide polymers, imide polymers, sulfone polymers, polyamides, Polyethersulfone polymers, polyetheretherketone polymers, polyphenylene Sulfide polymers, vinyl alcohol polymers, vinylidene chloride polymers, vinyl Nyl butyral polymers, arylate polymers, polyoxymethylene polymers, ethylene The transparent protective film may also be formed from an epoxy-based polymer or a blend of the polymers. Examples of polymers that can be used include acrylic, urethane, and acrylic polymers. Cured layer of thermosetting or UV-curable resin such as urethane, epoxy, or silicone. It can also be formed as

[0140] The thickness of the image display unit side protective film can be determined appropriately, but is generally determined based on strength, ease of handling, etc. From the viewpoint of workability and thin film properties, the thickness is about 1 to 500 μm.

[0141] The polarizer and the transparent protective film on the image display section side are also usually adhered to each other via a water-based adhesive or the like. Examples of the water-based adhesive include those mentioned above.

[0142] The surface of the transparent protective film on the image display section side to which the polarizer is not bonded is provided with a hard coat layer or Anti-reflective, anti-sticking, diffusion or anti-glare treatment It may also be something like that.

[0143] 2. Image display device The image display device of the present invention is characterized by using the polarizing film with the pressure-sensitive adhesive layer of the present invention. do.

[0144] As an example of a specific configuration of the image display device, for example, as shown in FIGS. Glass or cover plastic 6 / visible side adhesive layer 2a / visible side transparent protective film 3a / Polarizer 4 / Transparent protective film 3b on the image display section side / Adhesive layer 2b on the image display section side / LCD LCD or organic light-emitting diode (OLED) display device 7 (Figure 2); cover glass or cover Plastic 6 / adhesive layer 8a / sensor layer 9 / visual side adhesive layer 2a / visual side transparent protective film Film 3a / Polarizer 4 / Transparent protective film 3b on the image display section side / Adhesive layer 2b on the image display section side / Liquid crystal display (LCD) or organic light emitting diode (OLED) 7 (Figure 3); Cover glass or cover plastic 6 / adhesive layer 8a / sensor layer 9 / adhesive adhesive layer 8b / sensor layer 9 / visible-side adhesive layer 2a / visible-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 (LC D) or organic light-emitting diode (OLED) display device 7 (Figure 4); each layer is stacked in this order. The pressure-sensitive adhesive layer-attached polarizing film 1 of the present invention can be an image display device such as the above. In the configuration, "visible-side adhesive layer 2a / visible-side transparent protective film 3a / polarizer 4 / image display section side The transparent protective film 3b / image display section side adhesive layer 2b portion is also referred to as the "transparent protective film 3b / image display section side adhesive layer 2b" portion. In addition, when a retardation film is included, specifically, Image display portion side adhesive layer 2b and liquid crystal display device (LCD) or organic EL display device (OLED) 7 can be laminated via an adhesive layer. Adhesive and / or adhesive layers may be used.

[0145] Image display devices include liquid crystal display devices and organic EL (electroluminescence) display devices. These include LCDs, PDPs (plasma display panels), and electronic paper. Among these, liquid crystal display devices and organic EL (electroluminescence) displays having the above-mentioned configurations A device or the like is preferred. [Example]

[0146] The present invention will be specifically explained below with reference to examples. It should be noted that the parts and percentages in each example are all by weight.

[0147] Production Example 1 (Production 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 acrylate (HEA) 4 parts by weight The monomer mixture was mixed with 1-hydroxycyclohexylphenyl ether as a photopolymerization initiator. Luketone (trade name: Irgacure 184, which has an absorption band in the wavelength range of 200 to 370 nm) ASF) 0.035 parts by weight, 2,2-dimethoxy-1,2-diphenylethane-1- On (product name: Irgacure 651, with an absorption band in the wavelength range of 200 to 380 nm, BAS After blending 0.035 parts by weight of the mixture (manufactured by F Company), the viscosity (measurement conditions: BH viscometer No. 5 rotor) The temperature (10 rpm, 30°C) was irradiated with ultraviolet light until the temperature reached approximately 20 Pa·s. A prepolymer composition (polymerization rate: 8%) in which a portion of the monomer component was polymerized was obtained. The polymer composition contains 0.15 parts by weight of hexanediol diacrylate (HDDA), silane 0.3 parts by weight of a coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) was added. The ingredients were added and mixed to obtain an acrylic pressure-sensitive adhesive composition (a-1).

[0148] Production Example 2 (Production of acrylic pressure-sensitive adhesive composition (a-2)) 2-Ethylhexyl acrylate (2EHA) 72 parts by weight, methacrylic acid acrylate (MMA) 1 part by weight, N-vinylpyrrolidone (NVP) 12 parts by weight, hydroxyethyl alcohol A monomer mixture consisting of 15 parts by weight of acrylate (HEA) was added as a polymerization initiator. Add 0.2 parts by weight of azobisbutylnitrile (AIBN) and 233 parts by weight of ethyl acetate After that, the mixture was reacted at 60°C for 7 hours under a nitrogen atmosphere, whereby part of the monomer components was polymerized. Next, a silane coupling agent (trade name: KBM) was added to the partial polymer. -403, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.3 parts by weight, an isocyanate-based crosslinking agent as a crosslinking agent (trade name: Takenate D110N, manufactured by Mitsui Chemicals, Inc.) 0.21 parts by weight was added to A dispersant-based pressure-sensitive adhesive composition (a-2) was obtained.

[0149] Production Example 3 (Production of Image Display Side Pressure-Sensitive Adhesive Layer (B-1)) A separable flask equipped with a thermometer, a stirrer, a reflux condenser and a nitrogen gas inlet tube was charged with Butyric Acid. 95 parts by weight of acrylate, 5 parts by weight of acrylic acid, and azobisisobutyronitrile as a polymerization initiator. After adding 0.2 parts by weight of nitrile and 233 parts by weight of ethyl acetate, nitrogen gas was introduced and the mixture was stirred. The contents were purged with nitrogen for about 1 hour while stirring. After that, the flask was heated to 60°C and reacted for 7 hours. As a result, an acrylic polymer with a weight average molecular weight (Mw) of 1.1 million was obtained. The acrylic polymer solution (solid content: 100 parts by weight) was mixed with an isocyanate crosslinker. As a crosslinking agent, trimethylolpropane tolylene diisocyanate (trade name: Coronate L , manufactured by Nippon Polyurethane Industry Co., Ltd.) 0.8 parts by weight, silane coupling agent (trade name: KB 0.1 parts by weight of M-403 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added to prepare an adhesive composition (solution). did. 38 μm thick separator (polyethylene terephthalate film with release-treated surface) The obtained adhesive composition solution was applied onto a film (film) so that the thickness after drying would be 12 μm. The adhesive layer was then dried at 100°C for 3 minutes to remove the solvent, and a pressure-sensitive adhesive layer was obtained. This pressure-sensitive adhesive layer is hereinafter referred to as the "image display section side pressure-sensitive adhesive layer (B-1 )"

[0150] Production Example 4 (Production of Image Display Section Side Pressure-Sensitive Adhesive Layer (B-2)) 38 μm thick separator (polyethylene terephthalate film with release-treated surface) The pressure-sensitive adhesive composition solution obtained in Production Example 3 was applied onto a film (film) so that the thickness after drying would be 15 μm. The adhesive layer was then dried at 100°C for 3 minutes to remove the solvent, and a pressure-sensitive adhesive layer was obtained. The adhesive layer was heated at 0° C. for 48 hours to carry out a crosslinking treatment. Hereinafter, this adhesive layer will be referred to as the “image display section side adhesive layer.” It is called "Layer (B-2)".

[0151] Example 1 (Production of adhesive composition with ultraviolet absorbing function) The obtained acrylic pressure-sensitive adhesive composition (a-1) was mixed with butyl acrylate at a solid content of 15% and 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxybenzoate] {4-methoxyphenyl}-6-(4-methoxyphenyl)-1,3,5-triazine (product (Name: Tinosorb S, "UV absorber 1" in Tables 1 and 2, manufactured by BASF Japan) 1.4 parts by weight of bis(2,4,6-trimethylbenzoyl)-phenylphosphine Oxide (trade name: Irgacure 819, has absorption resistance in the wavelength range of 200 to 450 nm, B Add 0.2 parts by weight of ASF Japan Co., Ltd. and stir to form an adhesive with UV absorption properties. A pharmaceutical composition was obtained.

[0152] The pressure-sensitive adhesive composition with ultraviolet absorbing function is applied to a release-treated film of a release film. The adhesive composition was applied so that the thickness of the adhesive layer formed would be 150 μm. A release film was attached to the surface. Then, the illuminance was 6.5 mW / cm. 2 , light intensity: 15 00mJ / cm 2 The pressure-sensitive adhesive composition layer was irradiated with ultraviolet light at a peak wavelength of 350 nm. The resulting adhesive was photocured to form a visible-side pressure-sensitive adhesive layer (A-1).

[0153] (Production of polarizing film (P-1)) A polarizer made of a 5 μm thick stretched polyvinyl alcohol film impregnated with iodine. On the viewing side, a 25 μm thick cycloolefin polyimide film was attached using a polyvinyl alcohol adhesive. A COP film was attached to the polarizer, and a polyvinyl alcohol film was attached to the image display side of the polarizer. A 20 μm thick acrylic film was laminated using a polymer adhesive, and a polarizing film (P-1) was formed. The polarization degree of the polarizing film was 99.995.

[0154] (Manufacturing polarized film with adhesive layer) The viewing side of the polarizing film (P-1) (i.e., a cycloolefin polymer film with a thickness of 25 μm) The viewing side pressure-sensitive adhesive layer (A-1) was laminated on the surface of the polarizing plate (COP film). The image display surface of the film (P-1) (i.e., the acrylic film with a thickness of 20 μm) The pressure-sensitive adhesive layer (B-1) on the image display section side is laminated on the surface of the image display section, and then a retardation film (thickness: 56 μm, material: polycarbonate) and the image display side adhesive layer (B-2) are laminated and adhered. The obtained polarizing film with the pressure-sensitive adhesive layer was Layer (A-1) / Polarizing film (P-1) / Image display side adhesive layer (B-1) / Phase difference film The adhesive layer had a structure of film / image display section side pressure-sensitive adhesive layer (B-2).

[0155] Examples 2 and 3 The type of acrylic adhesive composition, the amount of ultraviolet absorber 1 added, and the thickness after forming the visible-side adhesive layer The polarized film with the adhesive layer was prepared in the same manner as in Example 1, except that the thickness of the polarized film was set as shown in Table 1. A new system was formed.

[0156] Example 4 The pressure-sensitive adhesive layer on the viewing side was obtained by dividing the pressure-sensitive adhesive layer on the viewing side (A-1) by the pressure-sensitive adhesive layer on the viewing side ( A polarizing film with adhesive was formed in the same manner as in Example 1, except that A-2) was used.

[0157] (Production of Viewing-Side Pressure-Sensitive Adhesive Layer (A-2)) The acrylic pressure-sensitive adhesive composition (a-2) obtained in Production Example 2 was dissolved in ethyl acetate at a solid content of 15%. 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxybenzoate] hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (commercial Add 1.4 parts by weight of Tinosorb S (product name: BASF Japan Ltd.) and stir. Thus, a pressure-sensitive adhesive composition with ultraviolet absorbing properties was obtained.

[0158] The pressure-sensitive adhesive composition with ultraviolet absorbing function is applied to a release-treated film of a release film. The adhesive layer was applied so that the thickness after formation was 150 μm, and then heated at 60°C for 2 minutes and at 120°C for 2 minutes. After drying for 1 minute, a release-treated film was attached to the visible-side adhesive layer (A-2 ) was formed.

[0159] Examples 5-6 The thickness of the visible-side adhesive layer after formation and the adhesive layer on the image display section side were as shown in Table 1. A polarizing film with a pressure-sensitive adhesive layer was formed in the same manner as in Example 4.

[0160] Example 7 (Production of Viewing-Side Pressure-Sensitive Adhesive Layer (A-3)) The acrylic pressure-sensitive adhesive composition (a-1) obtained in Production Example 1 was mixed with butyl acrylate to form a solid 2,4-bis-[{4-(4-ethylhexyloxy) -4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazole gin (Product name: Tinosorb S, manufactured by BASF Japan) 0.7 parts by weight, Solven Yellow 163 (KP Plast Yellow MK, "UV absorber" in Table 2) Collector 2 (Kiwa Chemical Industry Co., Ltd.) 0.2 parts by weight, bis(2,4,6-trimethylbenzoyl) Il)-phenylphosphine oxide (trade name: Irgacure 819, wavelength 200~ Add 0.2 parts by weight of a BASF Japan product with absorption at 450 nm and stir. Thus, a pressure-sensitive adhesive composition with ultraviolet absorbing properties was obtained.

[0161] The pressure-sensitive adhesive composition with ultraviolet absorbing function is applied to a release-treated film of a release film. The adhesive composition was applied so that the thickness of the adhesive layer formed would be 150 μm. A release film was attached to the surface. Then, the illuminance was 6.5 mW / cm. 2 , light intensity: 30 00mJ / cm 2 The pressure-sensitive adhesive composition layer was irradiated with ultraviolet light at a peak wavelength of 350 nm. The resulting adhesive was photocured to form a visible-side pressure-sensitive adhesive layer (A-3).

[0162] The pressure-sensitive adhesive layer on the viewing side was obtained by transferring the pressure-sensitive adhesive layer on the viewing side (A-1) to the pressure-sensitive adhesive layer on the viewing side ( A polarizing film with adhesive was formed in the same manner as in Example 1, except that A-3) was used.

[0163] Comparative Example 1 The visible-side pressure-sensitive adhesive layer (A-1), the retardation film, and the image display section side pressure-sensitive adhesive layer (B-2) A polarizing film with a pressure-sensitive adhesive layer was formed in the same manner as in Example 1, except that no adhesive layer was formed.

[0164] Comparative Example 2 The same procedure as in Example 1 was repeated except that the visible-side pressure-sensitive adhesive layer (A-1) was not formed. A polarizing film was formed.

[0165] Comparative Examples 3 and 4 The only difference was that no ultraviolet absorber was added to the visible-side pressure-sensitive adhesive layers (A-1) and (A-2). A polarizing film with adhesive was formed in the same manner as in Examples 1 and 4.

[0166] Comparative Example 5 (Production of polarizing film (P-2)) Polarizer made of 12 μm thick stretched polyvinyl alcohol film impregnated with iodine On the viewing side, a 25 μm thick triacetyl cellulose film was attached using a polyvinyl alcohol adhesive. A polyvinyl alcohol adhesive is applied to the surface of the polarizer on the image display side. An acrylic film having a thickness of 20 μm was laminated using the polarizing film (P-2). The polarization degree of the optical film was 99.995.

[0167] In Example 2, the polarizing film (P-1) was changed to the polarizing film (P-2). A polarizing film with adhesive was formed in the same manner as in Example 2, except for the above.

[0168] The resulting pressure-sensitive adhesive layer and the polarizing film with the pressure-sensitive adhesive layer were evaluated as follows.

[0169] <Polymerization rate> The release film of the visible side pressure-sensitive adhesive layer obtained in the examples and comparative examples was peeled off and the weight was measured. Only the adhesive layer on the viewing side was placed on the aluminum dish (aluminum dish + adhesive layer on the viewing side). The weight was measured to determine the weight of the adhesive layer before drying. After cooling for 10 minutes, the weight of the (aluminum dish + adhesive) was measured again, and the adhesive on the visible side after drying was measured. The weight of the adhesive layer was determined, and the polymerization rate was calculated using the following formula.

number

[0170] <Gel fraction> Approximately 0.1 g of the pressure-sensitive adhesive layer on the viewing side obtained in the examples and comparative examples was sampled, and the average pore size was 0.2 μm. 1 mm porous tetrafluoroethylene sheet (trade name: NTF1122, manufactured by Nitto Denko Corporation) ), and then tied with kite string. The weight at that time was measured (Zg), and this weight was used as the weight before immersion. The weight before immersion was the weight of the visible side adhesive layer (the adhesive layer collected above) and the tetrafluoroethylene The total weight of the tetrafluoroethylene sheet and the kite string. The total weight of the adhesive layer on the viewing side was also measured (Yg). The sample was wrapped in a plastic bag and tied with kite string. The sample was then placed in a 50 ml container filled with ethyl acetate. The sample was placed in a 1 L container and left to stand at 23°C for 7 days. After that, the sample (ethyl acetate treated) was taken out of the container. After that, the sample was taken out, transferred to an aluminum cup, and dried in a dryer at 130°C for 2 hours. After removing the ethyl acetate, the weight was measured (X g), and this weight was taken as the weight after immersion. The gel fraction was calculated from the formula. Gel fraction (wt%) = (XY) / (ZY) × 100

[0171] <Measurement of transmittance and b* value of the visible side adhesive layer> The release film of the visible-side adhesive layer obtained in the Examples and Comparative Examples was peeled off, and the visible-side adhesive The layer was attached to a measurement jig and measured with a spectrophotometer (product name: U4100, Hitachi High-Technologies Corporation). The transmittance was measured using a 380nm, 400nm, and 420nm wavelength LC filter. The transmittance was measured (however, the wavelength of 420 nm was measured only in Examples 2 and 7).

[0172] <Residual stress> A piece of 30 mm wide and 50 mm long was cut out from the visible side pressure-sensitive adhesive layer obtained in the examples and comparative examples. The test piece was placed with a chuck distance of 20 mm and subjected to tension. The specimen was pulled 60 mm (300%) at a speed of 200 mm / min (the distance between the chucks after pulling was 80 m). m). The specimen is pulled 60 mm and held at this position for 300 seconds. The stress value (N ) was measured. The residual stress was calculated using the following formula. Residual stress after 300 seconds = stress value after 300 seconds (N) / (4 × thickness of test piece / 10)

[0173] <Optical reliability> The COP film of the polarizing film (P-1) used in Example 1 was used in Examples 1 to 7. The pressure-sensitive adhesive layers on the viewing side obtained in Comparative Examples 3 to 5 were laminated. The reverse side of the polarizing film (acrylic film side) is 56μm thick with 15μm adhesive. A retardation film (manufactured by Nitto Denko Corporation) was attached to the sample. Both sides of the sample were covered with glass (commercially available). Product name: S200200, thickness: 1.3mm, size: 45mm x 50mm, Matsunami Glass Industry Co., Ltd.) and autoclave treatment (pressure: 0.5 MPa, temperature: 50°C) ) was carried out for 15 minutes. After that, it was placed under the following various reliability conditions and measured with a spectral transmittance measuring instrument ( The transmittance was measured using a product called DOT-3 (manufactured by Murakami Color Research Institute Co., Ltd.). The change in the transmittance was determined and evaluated according to the following criteria. (Various reliability conditions) (Condition 1) 85℃×500h (Condition 2) 60℃, 95% x 500h (Condition 3) Heat shock (HS) (-40℃ to 85℃) x 300 cycles (Condition 4) Under UV irradiation × 100h, illuminance: 500W / cm 2 (300~700nm), ring Environmental temperature: 60~65℃, environmental humidity: 50% (Condition 5) Under Xenon irradiation × 300h, illuminance: 2.40W / cm 2 (420nm), Ring Environmental temperature: 50℃, environmental humidity: 30% (Evaluation criteria) ◯: The amount of change in transmittance is 2.0% or less. △: The amount of change in transmittance is more than 2.0% and 3.0% or less. ×: The amount of change in transmittance exceeds 3.0%.

[0174] <Glue stains, dimensional accuracy, edge appearance> The polarized films with pressure-sensitive adhesive layers obtained in the Examples and Comparative Examples were cut into 25 pieces using a super cutter. The pieces were cut into pieces measuring 30 mm x 30 mm. Then, they were cut into pieces using an end-face processing machine (Megalo Technica Co., Ltd.). Therefore, 0.05 mm was removed from the four sides of the cut piece to prepare a sample. The side of the sample was visually inspected to check for glue stains. The sample was observed under an optical microscope and evaluated according to the following criteria. (dimensional accuracy) ○:Within ±0.3mm ×: Exceeds ±0.3 mm (Exterior view of end) ○: When the edge is not sticky when touched with the hand ×: If the edge is sticky when touched with your hand

[0175] <Curl measurement> A sample cut to 50mm x 40mm was placed on a flat table and The curl was measured by a tape measure. (curl) ○: Within ±1.0 mm △: More than ±1.0mm, within ±2.0mm ×: Greater than ±2.0 mm

[0176] [Table 1]

[0177] [Table 2]

[0178] In Table 1, P-1 refers to the polarizing film (P-1), and P-2 refers to the polarizing film (P-2). a-1 is the acrylic pressure-sensitive adhesive composition (a-1) obtained in Production Example 1, and a-2 is the acrylic pressure-sensitive adhesive composition (a-2) obtained in Production Example 2. The acrylic pressure-sensitive adhesive composition (a-2) obtained in Example 2 was treated with ultraviolet absorber 1 containing 2,4-bis(2,4-dichloro-2,4-dichloro-1 ... -[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4- methoxyphenyl)-1,3,5-triazine (trade name: Tinosorb S, BAS UV absorber 2 is Solvent Yellow 163 (KP Plasma Yellow MK (manufactured by Kiwa Chemical Industry Co., Ltd.) was used, and B-1 was the same as that obtained in Production Example 3. The pressure-sensitive adhesive layer (B-1) on the image display portion side obtained in Production Example 4 was used as the pressure-sensitive adhesive layer (B-2). The pressure-sensitive adhesive layer (B-2) is shown. [Explanation of symbols]

[0179] 1. Polarized film with adhesive layer 2a Visible side adhesive layer 2b Adhesive layer on image display side 3a Transparent protective film on the viewing side 3b Transparent protective film on the image display side 4 Polarizer 5. Polarizing film 6 Cover glass or cover plastic 7 Liquid crystal display (LCD) or organic light emitting diode (OLED) display 8a, 8b adhesive layer 9 Sensor Layer

Claims

1. A polarizing film with a pressure-sensitive adhesive layer used on the viewing side of an image display unit in an image display device, The polarizing film with a pressure-sensitive adhesive layer includes a polarizing film and pressure-sensitive adhesive layers on both sides of the polarizing film, the polarizing film has a polarizer and transparent protective films on both sides of the polarizer; The transparent protective film on the viewing side of the polarizer has a transmittance at a wavelength of 380 nm of less than 6%, and A polarizing film with an adhesive layer, wherein the adhesive layer on the viewing side of the polarizing film has an ultraviolet absorbing function.

2. 2. The polarizing film with a pressure-sensitive adhesive layer according to claim 1, wherein 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 has a thickness of 40 μm or less.

3. 3. The polarizing film with an adhesive layer according to claim 1, wherein the thickness of the adhesive layer on the viewing side of the polarizing film is at least twice the thickness of the adhesive layer on the image display side of the polarizing film.

4. The polarized film with a pressure-sensitive adhesive layer according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer on the viewing side of the polarized film has a transmittance of 9% or less at a wavelength of 380 nm and a transmittance of 60% or more at a wavelength of 400 nm.

5. The polarizing film with a pressure-sensitive adhesive layer according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer on the viewing side of the polarizing film has a transmittance of 9% or less at a wavelength of 380 nm and a transmittance of 75% or less at a wavelength of 420 nm.

6. 5. The polarizing film with a pressure-sensitive adhesive layer according to claim 1, wherein the b* value of the pressure-sensitive adhesive layer on the viewing side of the polarizing film is 3.0 or less.

7. 7. The polarizing film with a pressure-sensitive adhesive layer according to claim 1, wherein the pressure-sensitive adhesive layer on the viewing side of the polarizing film contains an acrylic polymer as a base polymer.

8. 8. The polarizing film with a pressure-sensitive adhesive layer according to claim 1, which is used in a liquid crystal display device or an organic EL display device.

9. An image display device, characterized in that the polarizing film with the pressure-sensitive adhesive layer according to any one of claims 1 to 8 is used on the viewing side of an image display section.

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