JP6931339B2 - Polarizing film with adhesive layer and image display device - Google Patents

Description

The present invention relates to a polarizing film and a polarizing film with an adhesive layer having an adhesive layer provided on the polarizing film. Furthermore, the present invention relates to an image display device such as a liquid crystal display device, an organic EL display device, and a PDP using the polarizing film with an adhesive layer.

In a liquid crystal display device or the like, it is indispensable to arrange polarizing elements on both sides of a liquid crystal cell due to the image forming method, and generally, a polarizing film is attached. When the polarizing film is attached to the liquid crystal cell, an adhesive is usually used. Further, in order to reduce the loss of light, the polarizing film and the liquid crystal cell are usually adhered to each other by using an adhesive. In such a case, since there is an advantage that a drying step is not required to fix the polarizing film, the pressure-sensitive adhesive is polarized light with a pressure-sensitive adhesive layer previously provided as a pressure-sensitive adhesive layer on one side of the polarizing film. Films are commonly used. A release film is usually attached to the pressure-sensitive adhesive layer of the polarizing film with the pressure-sensitive adhesive layer.

At the time of manufacturing the liquid crystal display device, when the polarizing film with the pressure-sensitive adhesive layer is attached to the liquid crystal cell, the release film is peeled from the pressure-sensitive adhesive layer of the polarizing film with the pressure-sensitive adhesive layer. Static electricity is generated. The static electricity generated in this way affects the orientation of the liquid crystal inside the liquid crystal display device and causes defects. In addition, display unevenness may occur due to static electricity when using the liquid crystal display device. The generation of static electricity can be suppressed, for example, by forming an antistatic layer on the outer surface of the polarizing film, but the effect is small and there is a problem that the generation of static electricity cannot be fundamentally prevented. Therefore, in order to suppress the generation of static electricity at the fundamental position, it is required to impart an antistatic function to the adhesive layer. As a means for imparting an antistatic function to the pressure-sensitive adhesive layer, for example, it has been proposed to add an ionic compound to the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer (Patent Documents 1 and 2). Patent Document 1 is an ionic solid containing an imidazolium cation and an inorganic anion, and Patent Document 2 is a liquid at room temperature such as an onium salt composed of a cation having 6 to 50 carbon atoms containing a quaternary nitrogen atom and a fluorine atom-containing anion. It is described that the organic molten salt of No. 1 is blended with an acrylic pressure-sensitive adhesive used for a polarizing film. Further, a method of providing an antistatic layer between a polarizing film and an adhesive layer by using a binder of a conductive polymer such as polythiophene has been proposed (Patent Document 3). Further, the polarizing film with an adhesive layer is required to have durability in an adhesive state.

Japanese Unexamined Patent Publication No. 2009-251281 International Publication No. 2007/0345533 Pamphlet Japanese Unexamined Patent Publication No. 2003-246874

In Patent Documents 1 and 2, an antistatic function is imparted by applying a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive composition containing an ionic compound to a polarizing film. In all the polarizing films applied in Patent Documents 1 and 2, those having a protective base material such as a transparent protective film on both sides of the polarizer are used.

On the other hand, as the polarizing film with an adhesive layer, a polarizing film with an adhesive layer provided with an adhesive layer is used without providing a transparent protective film on only one side of the polarizer and without providing a transparent protective film on the other side. In some cases. Since the polarizing film with the pressure-sensitive adhesive layer has the transparent protective film on only one side, the cost for one layer of the transparent protective film can be reduced as compared with the case where the transparent protective film is provided on both sides, but the pressure-sensitive adhesive layer is ionized. When an ionic compound is contained to impart an antistatic function, the ionic compound in the pressure-sensitive adhesive layer has a large effect on the polarizer. For example, an ionic liquid and an ionic solid are used as the ionic compound. If so, there is a problem that the polarizer is deteriorated and the optical characteristics are significantly deteriorated after the humidification test.

Further, when a layer containing a conductive polymer such as polythiophene is provided on the polarizing film and the pressure-sensitive adhesive layer as in Patent Document 3, the polarizer is deteriorated and the optical characteristics are deteriorated.

An object of the present invention is to provide a polarizing film with an adhesive layer which has an antistatic function, has an adhesive layer satisfying durability, and has little deterioration in optical characteristics.

Another object of the present invention is to provide an image display device using the polarizing film with an adhesive layer.

As a result of diligent studies to solve the above problems, the present inventors have found the following polarizing film with an adhesive layer, and have completed the present invention.

That is, the present invention is a polarizing film and a polarizing film with an adhesive layer having an adhesive layer provided on the polarizing film.
The polarizing film has a transparent protective film on only one side of the polarizer, the pressure-sensitive adhesive layer is provided on the polarizer on the side that does not have the transparent protective film, and the pressure-sensitive adhesive layer is (meth. ) A polarizing film with a pressure-sensitive adhesive layer, which is formed from a pressure-sensitive adhesive composition containing an acrylic polymer (A) and an onium-fluorine-containing imide anion salt (B).

In the polarizing film with an adhesive layer, the onium in the onium-fluorine-containing imide anion salt (B) is preferably at least one selected from nitrogen-containing onium, sulfur-containing onium, and phosphorus-containing onium.

Further, in the polarizing film with an adhesive layer, it is preferable that the onium in the onium-fluorine-containing imide anion salt (B) is at least one selected from ammonium, pyrrolidinium, piperidinium and sulfonium.

Further, in the polarizing film with an adhesive layer, it is preferable that the onium in the onium-fluorine-containing imide anion salt (B) does not have an unsaturated bond.

Further, in the polarizing film with an adhesive layer, the onium in the onium-fluorine-containing imide anion salt (B) is preferably an alkyl onium having an alkyl group having 1 to 4 carbon atoms.

The polarizing film with an adhesive layer preferably contains 0.1 to 10 parts by weight of the onium-fluorine-containing imide anion salt (B) with respect to 100 parts by weight of the (meth) acrylic polymer (A).

In the polarizing film with an adhesive layer, a polarizing film having a thickness of 10 μm or less can be used.

In the polarizing film with an adhesive layer, the (meth) acrylic polymer (A) preferably contains an alkyl (meth) acrylate and a hydroxyl group-containing monomer as a monomer unit.

In the polarizing film with an adhesive layer, the (meth) acrylic polymer (A) preferably contains an alkyl (meth) acrylate and a carboxyl group-containing monomer as a monomer unit.

In the polarizing film with the pressure-sensitive adhesive layer, the pressure-sensitive adhesive composition can further contain a cross-linking agent (C). In the pressure-sensitive adhesive composition, the cross-linking agent (C) is preferably contained in an amount of 0.01 to 20 parts by weight with respect to 100 parts by weight of the (meth) acrylic polymer (A). The cross-linking agent (C) is preferably at least one selected from isocyanate compounds and peroxides.

The polarizing film with an adhesive layer can further contain 0.001 to 5 parts by weight of the silane coupling agent (D) with respect to 100 parts by weight of the (meth) acrylic polymer (A).

The polarizing film with an adhesive layer can further contain 0.001 to 10 parts by weight of the polyether-modified silicone compound with respect to 100 parts by weight of the (meth) acrylic polymer (A).

In the polarizing film with an adhesive layer, the weight average molecular weight of the (meth) acrylic polymer (A) is preferably 500,000 to 3,000,000.

The polarizing film with an adhesive layer may have an easy-adhesive layer between the polarizing film and the adhesive layer.

The present invention also relates to an image display device characterized in that at least one polarizing film with an adhesive layer is used.

In a pressure-sensitive adhesive using an acrylic polymer as a base polymer, an antistatic function can be imparted by blending the pressure-sensitive adhesive with an ionic compound. In this case, it is considered that the antistatic function is efficiently exhibited by bleeding out the ionic compound on the surface of the pressure-sensitive adhesive layer. On the other hand, when the ionic compound comes into contact with the polarizer, optical characteristics such as the degree of polarization may deteriorate.

The pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer of the polarizing film with a pressure-sensitive pressure-sensitive adhesive layer of the present invention can impart an antistatic function in addition to the (meth) acrylic polymer (A) which is a base polymer. The pressure-sensitive adhesive layer, which contains an onium-fluorine-containing imide anionic salt (B) as a sex compound and is formed by the pressure-sensitive adhesive composition, has an excellent antistatic function. Further, in the present invention, it has been found that by using the onium-fluorine-containing imide anion salt (B), an antistatic function can be imparted without causing deterioration of the polarizer.

The pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer of the polarizing film with a pressure-sensitive adhesive layer of the present invention contains a (meth) acrylic polymer (A) as a base polymer. The (meth) acrylic polymer (A) usually contains an alkyl (meth) acrylate as a main component as a monomer unit. In addition, (meth) acrylate means acrylate and / or methacrylate, and has the same meaning as (meth) of the present invention.

Examples of the alkyl (meth) acrylate constituting the main skeleton of the (meth) acrylic polymer (A) include linear or branched alkyl groups having 1 to 18 carbon atoms. For example, the alkyl group includes a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an amyl group, a hexyl group, a cyclohexyl group, a heptyl group, a 2-ethylhexyl group, an isooctyl group, a nonyl group and a decyl group. Examples thereof include a group, an isodecyl group, a dodecyl group, an isomyristyl group, a lauryl group, a tridecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group and the like. These can be used alone or in combination. The average number of carbon atoms of these alkyl groups is preferably 3 to 9.

The (meth) acrylic polymer (A) has a polymerizable functional group having an unsaturated double bond such as a (meth) acryloyl group or a vinyl group for the purpose of improving adhesiveness and heat resistance. One or more types of copolymerization monomers can be introduced by copolymerization. Specific examples of such a copolymerization monomer include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 6 (meth) acrylate. Hydroxyl group-containing monomers such as −hydroxyhexyl, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate and (4-hydroxymethylcyclohexyl) -methylacrylate. Carboxyl group-containing monomers such as (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; acid anhydrides such as maleic anhydride and itaconic anhydride. Group-containing monomer; caprolactone adduct of acrylic acid; styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, ( Meta) Examples thereof include sulfonic acid group-containing monomers such as acryloyloxynaphthalene sulfonic acid; and phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate.

Further, (N-substituted) amides such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, and N-methylolpropane (meth) acrylamide. Monomer; (meth) alkylaminoalkyl-acrylate monomer such as aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate; (meth) acrylic (Meta) alkoxyalkyl-based monomers such as methoxyethyl acid and ethoxyethyl (meth) acrylate; N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, N-( Meta) Succinimide-based monomers such as acryloyl-8-oxyoctamethylene succinimide and N-acryloylmorpholin; maleimide-based monomers such as N-cyclohexyl maleimide, N-isopropyl maleimide, N-lauryl maleimide and N-phenylmaleimide; N-methylitacon Italonimide-based monomers such as imide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, and N-laurylitaconimide are also used for modification. As an example of the monomer of.

Further, as modified monomers, vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazin, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholin, N- Vinyl-based monomers such as vinylcarboxylic acid amides, styrene, α-methylstyrene, N-vinylcaprolactam; cyanoacrylate-based monomers such as acrylonitrile and methacrylonitrile; epoxy group-containing acrylic monomers such as glycidyl (meth) acrylate; Glycol-based acrylic ester monomers such as (meth) polyethylene glycol acrylate, (meth) polypropylene glycol acrylate, (meth) methoxyethylene glycol acrylate, (meth) methoxypolypropylene glycol acrylate; (meth) tetrahydrofurfuryl acrylate, Acrylic acid ester-based monomers such as fluorine (meth) acrylate, silicone (meth) acrylate and 2-methoxyethyl acrylate can also be used. Further, isoprene, butadiene, isobutylene, vinyl ether and the like can be mentioned.

Further, as a copolymerizable monomer other than the above, a silane-based monomer containing a silicon atom and the like can be mentioned. Examples of the silane-based monomer include 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, and 8-vinyloctyltrimethoxysilane. , 8-Vinyloctyloxydecyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, 10-acryloyloxydecyltriethoxysilane and the like.

Examples of the copolymerization monomer include tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, and neo. Pentyl glycol di (meth) acrylate, trimethyl propantri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Caprolactone-modified dipentaerythritol Hexa (meth) Acrylate and other (meth) acrylic acids and polyhydric alcohols such as esterified products such as (meth) acryloyl groups and vinyl groups and other unsaturated double bonds having two or more unsaturated double bonds. Polyester (meth) acrylates and epoxys (meth) acrylates and epoxys in which two or more unsaturated double bonds such as (meth) acryloyl groups and vinyl groups are added as functional groups similar to the monomer components to the skeletons of sex monomers, polyesters, epoxys, urethanes, etc. Meta) acrylate, urethane (meth) acrylate and the like can also be used.

The (meth) acrylic polymer (A) contains an alkyl (meth) acrylate as a main component in the weight ratio of all the constituent monomers, and the ratio of the copolymerized monomer in the (meth) acrylic polymer (A) is particularly limited. However, the proportion of the copolymerized monomer is preferably about 0 to 20%, about 0.1 to 15%, and more preferably about 0.1 to 10% in terms of the weight ratio of all the constituent monomers.

Among these copolymerizable monomers, a hydroxyl group-containing monomer and a carboxyl group-containing monomer are preferably used from the viewpoint of adhesiveness and durability. A hydroxyl group-containing monomer and a carboxyl group-containing monomer can be used in combination. These copolymerizable monomers serve as reaction points with the cross-linking agent when the pressure-sensitive adhesive composition contains the cross-linking agent. Since the hydroxyl group-containing monomer and the carboxyl group-containing monomer are highly reactive with the intermolecular cross-linking agent, they are preferably used for improving the cohesiveness and heat resistance of the obtained pressure-sensitive adhesive layer. The hydroxyl group-containing monomer is preferable in terms of reworkability, and the carboxyl group-containing monomer is preferable in terms of achieving both durability and reworkability.

When a hydroxyl group-containing monomer is contained as the copolymerization monomer, the ratio thereof is preferably 0.01 to 15% by weight, more preferably 0.03 to 10% by weight, and further preferably 0.05 to 7% by weight. .. When a carboxyl group-containing monomer is contained as the copolymerization monomer, the proportion thereof is preferably 0.05 to 10% by weight, more preferably 0.1 to 8% by weight, and further preferably 0.2 to 6% by weight. ..

As the (meth) acrylic polymer (A) of the present invention, a polymer having a weight average molecular weight in the range of 500,000 to 3,000,000 is usually used. Considering durability, particularly heat resistance, it is preferable to use one having a weight average molecular weight of 700,000 to 2.7 million. Further, it is preferably 800,000 to 2.5 million. If the weight average molecular weight is less than 500,000, it is not preferable in terms of heat resistance. Further, when the weight average molecular weight is larger than 3 million, a large amount of diluting solvent is required to adjust the viscosity for coating, which is not preferable because it increases the cost. The weight average molecular weight is a value measured by GPC (gel permeation chromatography) and calculated in terms of polystyrene.

For the production of such a (meth) acrylic polymer (A), known production methods such as solution polymerization, bulk polymerization, emulsion polymerization, and various radical polymerizations can be appropriately selected. Further, the obtained (meth) acrylic polymer (A) may be any of a random copolymer, a block copolymer, a graft copolymer and the like.

In solution polymerization, for example, ethyl acetate, toluene and the like are used as the polymerization solvent. As a specific example of solution polymerization, the reaction is carried out under an inert gas stream such as nitrogen, a polymerization initiator is added, and usually at about 50 to 70 ° C. under reaction conditions of about 5 to 30 hours.

The polymerization initiator, chain transfer agent, emulsifier and the like used for radical polymerization are not particularly limited and can be appropriately selected and used. The weight average molecular weight of the (meth) acrylic polymer (A) can be controlled by the amount of the polymerization initiator and the chain transfer agent used, and the reaction conditions, and the amount used is appropriately adjusted according to these types. NS.

Examples of the polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-amidinopropane) dihydrochloride, and 2,2'-azobis [2- (5-methyl-2). -Imidazoline-2-yl) propane] dihydrochloride, 2,2'-azobis (2-methylpropionamidine) disulfate, 2,2'-azobis (N, N'-dimethyleneisobutylamidine), 2,2 Azo-based initiators such as ´-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate (manufactured by Wako Pure Chemical Industries, Ltd., VA-057), persulfates such as potassium persulfate and ammonium persulfate. , Di (2-ethylhexyl) peroxydicarbonate, di (4-t-butylcyclohexyl) peroxydicarbonate, di-sec-butylperoxydicarbonate, t-butylperoxyneodecanoate, t-hexylper Oxypivalate, t-butylperoxypivalate, dilauroyl peroxide, di-n-octanoyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, di (4) Peroxides such as -methylbenzoyl) peroxide, dibenzoyl peroxide, t-butylperoxyisobutyrate, 1,1-di (t-hexylperoxy) cyclohexane, t-butylhydroperoxide, hydrogen peroxide, etc. Examples thereof include an initiator, a combination of persulfate and sodium hydrogen sulfite, and a redox-based initiator that combines a peroxide and a reducing agent such as a combination of peroxide and sodium ascorbate, but the present invention is limited to these. It's not something.

The polymerization initiator may be used alone or in combination of two or more, but the total content is 0.005 to 1 part by weight with respect to 100 parts by weight of the monomer. It is preferably about 0.02 to 0.5 parts by weight, and more preferably about 0.02 to 0.5 parts by weight.

In addition, in order to produce the (meth) acrylic polymer (A) having the weight average molecular weight by using, for example, 2,2'-azobisisobutyronitrile as the polymerization initiator, the amount of the polymerization initiator used. Is preferably about 0.06 to 0.2 parts by weight, more preferably about 0.08 to 0.175 parts by weight, based on 100 parts by weight of the total amount of the monomer components.

Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglucolate, 2,3-dimercapto-1-propanol and the like. The chain transfer agent may be used alone or in combination of two or more, but the total content is 0.1 part by weight with respect to 100 parts by weight of the total amount of the monomer components. It is below the degree.

Examples of the emulsifier used in the case of emulsifying polymerization include anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzene sulfonate, ammonium polyoxyethylene alkyl ether sulfate, and sodium polyoxyethylene alkyl phenyl ether sulfate, and polyoxy. Examples thereof include nonionic emulsifiers such as ethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, and polyoxyethylene-polyoxypropylene block polymer. These emulsifiers may be used alone or in combination of two or more.

Further, as an emulsifier into which a radically polymerizable functional group such as a propenyl group or an allyl ether group has been introduced as a reactive emulsifier, specifically, for example, Aqualon HS-10, HS-20, KH-10, BC-05. , BC-10, BC-20 (all manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Adecaria Soap SE10N (manufactured by Asahi Denko Co., Ltd.) and the like. Since the reactive emulsifier is incorporated into the polymer chain after polymerization, it has good water resistance and is preferable. The amount of the emulsifier used is more preferably 0.3 to 5 parts by weight and 0.5 to 1 part by weight from the viewpoint of polymerization stability and mechanical stability with respect to 100 parts by weight of the total amount of the monomer components.

The pressure-sensitive adhesive composition of the present invention contains the onium-fluorine-containing imide anion salt (B) in addition to the (meth) acrylic polymer (A). The onium-fluorine-containing imide anion salt (B) is related to an "ionic compound", and the "ionic compound" is also referred to as an ionic liquid or an ionic solid. The onium-fluorine-containing imide anion salt (B) relates to a cation-anion salt composed of a cation component and an anion component. In the present invention, among the cation-anion salts, an onium-fluorine-containing imide anion salt in which the cation is onium and the anion is a fluorine-containing imide anion is used.

<Fluorine-containing imide anion>
As the fluorine-containing imide anion constituting the anion portion in the onium-fluorine-containing imide anion salt (B), for example, an imide anion having a perfluoroalkyl group can be exemplified.
Specifically, (CF ₃ SO ₂ ) (CF ₃ CO) N ⁻ , and the following general formulas (1) to (3),
(1): (C _n F _{2n + 1} SO ₂ ) ₂ N ⁻ (where n is an integer of 1 to 10),
(2): CF ₂ (C _m F _{2 m} SO ₂ ) ₂ N ⁻ (where m is an integer of 1 to 10),
(3): (C _p F _{2p + 1} SO ₂ ) N ⁻ (C _q F _{2q + 1} SO ₂ ), (where p and q are integers of 1 to 10), and the like are used. These fluorine-containing imide anions are preferably used because an ionic compound having good ionic dissociation property can be obtained. Further, the fluorine-containing imide anion having an alkyl fluoride group or an alkylene fluoride group having 1 to 4 carbon atoms is preferable in that the surface resistance value can be controlled to be small and static electricity unevenness can be suppressed. As the fluorine-containing imide anion, (perfluoroalkylsulfonyl) imide represented by the general formula (1) such _{as (CF 3} SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ^{−, etc. is preferable.} In particular, the (trifluoromethanesulfonyl) imide represented by _{(CF 3} SO ₂ ) ₂ N ^{−, is preferred.}

<Onium>
As the onium constituting the cation portion in the onium-fluorine-containing imide anion salt (B), an atom that becomes an onium ion is protonated. Further, the onium of the present invention preferably does not form an onium salt by an unsaturated bond such as a double bond or a triple bond from the viewpoint of suppressing deterioration of the polarizer. That is, as the onium of the present invention, organic onium in which onium ions are formed by substitution with an organic group or the like is preferable.

Further, examples of the organic group in the organic onium include an alkyl group, an alkoxyl group, and an alkenyl group. Among these, those having no unsaturated bond are preferable in order to suppress deterioration of the polarizer. The number of carbon atoms of the alkyl group can be selected from, for example, 1 to 12, but is preferably 1 to 8, and more preferably 1 to 4. As the organic onium, it is preferable that all the substituents are alkyl onium having an alkyl group having 1 to 4 carbon atoms. A straight chain or a branched chain can be used as the alkyl group, but a straight chain is preferable. When the organic onium has a cyclic structure, it is preferable that the onium has a 5-membered ring or a 6-membered ring, and the other substituent is an alkyl group having 1 to 4 carbon atoms.

The onium is not particularly limited, and examples thereof include nitrogen-containing onium, sulfur-containing onium, and phosphorus-containing onium. Of these, nitrogen-containing onium and sulfur-containing onium are preferable.

The nitrogen-containing onium includes ammonium cation, piperidinium cation, pyrrolidinium cation, pyridinium cation, pyrrolin skeleton cation, pyrrole skeleton cation, imidazolium cation, tetrahydropyrimidinium cation, dihydropyrimidinium cation, Examples thereof include pyrazolium cation and pyrazolinium cation. Among these, ammonium cations, piperidinium cations, and pyrrolidinium cations are preferable from the viewpoint of polarization deterioration. In particular, tetraalkylammonium cations, alkylpiperidinium cations, and alkylpyrrolidinium cations are preferable.

Examples of sulfur-containing onium include sulfonium cations and the like. Examples of the phosphorus-containing cation include a phosphonium cation and the like.

As a specific example of the onium-fluorine-containing imide anion salt, a compound composed of a combination of the above onium component and the fluorine-containing imide anion component is appropriately selected and used, and is selected from nitrogen-containing onium salt, sulfur-containing onium salt and phosphorus-containing onium salt. At least one selected is preferably used. Furthermore, at least one selected from ammonium salt, pyrrolidinium salt, piperidinium salt and sulfonium salt is preferably used.

For example, 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide, 1-butyl-3-methylpyridinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-3-methylimidazolium bis (trifluoromethanesulfonyl). Imide, 1-ethyl-3-methylimidazolium bis (pentafluoroethanesulfonyl) imide, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1,2-dimethyl-3-propylimidazolium bis (1,2-dimethyl-3-propylimidazolium bis) Trifluoromethanesulfonyl) imide, tetrahexyl ammonium bis (trifluoromethanesulfonyl) imide, diallyldimethylammonium bis (trifluoromethanesulfonyl) imide, diallyldimethylammonium bis (pentafluoroethanesulfonyl) imide, N, N-diethyl-N-methyl- N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (pentafluoroethanesulfonyl) imide, glycidyltrimethylammonium bis ( Trifluoromethanesulfonyl) imide, glycidyltrimethylammonium bis (pentafluoroethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl- N-Butylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-hexylammonium bis (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-heptylammonyl bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-nonyl ammonium bis (trifluoromethanesulfonyl) imide , N, N-dimethyl-N, N-dipropylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl- N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N -Hexyl ammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-heptyl ammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-butyl-N-hexyl ammonium bis (trifluo) Lomethanesulfonyl) imide, N, N-dimethyl-N-butyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-pentyl-N-hexyl ammoniumbis (trifluoromethanesulfonyl) imide, N , N-dimethyl-N, N-dihexyl ammonium bis (trifluoromethanesulfonyl) imide, trimethylheptyl ammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-propylammon bis (trifluoromethanesulfonyl) Imide, N, N-diethyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N- Diethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, triethylpropylammonium bis (trifluoromethanesulfonyl) imide, triethylpentylammonium bis (trifluoromethanesulfonyl) imide, triethylheptylammonium bis (trifluoromethanesulfonyl) imide , N, N-dipropyl-N-methyl-N-ethylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl -N-butyl-N-hexyl ammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N, N-dihexyl ammonium bis (trifluoromethanesulfonyl) imide, N, N-dibutyl-N-methyl-N- Pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dibutyl-N-methyl-N-hexyl ammonium bis (trifluoromethanesulfonyl) imide, trioctylmethylammonium bis (trifluoromethanesulfonyl) imide, N-methyl-N- Ethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfoni) Le) Imide, etc. As these commercially available products, for example, "CIL-314" (manufactured by Carlit Japan Co., Ltd.), "ILA2-1" (manufactured by Koei Chemical Industry Co., Ltd.) and the like can be used.

Further, for example, tetramethylammonium bis (trifluoromethanesulfonyl) imide, trimethylethylammonium bis (trifluoromethanesulfonyl) imide, trimethylbutylammonium bis (trifluoromethanesulfonyl) imide, trimethylpentylammonium bis (trifluoromethanesulfonyl) imide, trimethylheptyl. Ammonium bis (trifluoromethanesulfonyl) imide, trimethyloctylammonbis (trifluoromethanesulfonyl) imide, tetraethylammonbis (trifluoromethanesulfonyl) imide, triethylbutylammonbis (trifluoromethanesulfonyl) imide, tetrabutylammonium bis (trifluoromethanesulfonyl) Examples include imide, tetrahexyl ammonium bis (trifluoromethanesulfonyl) imide, and the like.

Further, for example, 1-dimethylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-ethylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-propylpyrrolidinium bis (trifluoromethane). Sulfonyl) imide, 1-methyl-1-butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-pentylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-hexylpyrrolidinium Bis (trifluoromethanesulfonyl) imide, 1-methyl-1-heptylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-propylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1 -Butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-pentylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-Ethyl-1-heptylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1,1-dipropylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-propyl-1-butylpyrrolidinium bis (trifluoromethane) Sulfonyl) imide, 1,1-dibutylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-propylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-pentylpiperidinium bis (trifluoromethanesulfonyl) imide, 1, 1-Dimethylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-ethylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-propylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-Methyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-pentylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-hexylpiperidinium bis (trifluoromethane) Sulfonyl) imide, 1-methyl-1-heptylpiperidiniumbis (trifluoromethanesulfonyl) imide, 1-ethyl-1-propylpiperidiniumbis (trifluoromethanesulfonyl) imide, 1- Ethyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-pentylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-hexylpiperidinium bis (trifluoromethanesulfonyl) Imide, 1-ethyl-1-heptyl piperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dipropyl piperidinium bis (trifluoromethanesulfonyl) imide, 1-propyl-1-butyl piperidinium bis (trifluo) Lomethanesulfonyl) imide, 1,1-dibutylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dimethylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-ethylpyrrolidinium bis (1-methyl-1-ethylpyrrolidinium bis) Pentafluoroethanesulfonyl) imide, 1-methyl-1-propylpyrrolidiniumbis (pentafluoroethanesulfonyl) imide, 1-methyl-1-butylpyrrolidiniumbis (pentafluoroethanesulfonyl) imide, 1-methyl-1 -Pentylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-hexylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-heptylpyrrolidinium bis (pentafluoroethanesulfonyl) ) Imide, 1-ethyl-1-propylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-butylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-pentylpyrrolidi Niumbis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-hexylpyrrolidiniumbis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-heptylpyrrolidiniumbis (pentafluoroethanesulfonyl) imide, 1 , 1-Dipropylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-propyl-1-butylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dibutylpyrrolidinium bis (pentafluoroethanesulfonyl) imide ) Imide, 1-propyl piperidinium bis (pentafluoroethanesulfonyl) imide, 1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dimethylpiperidinium bis (pentafluoroethanesulfonyl) a Mido, 1-methyl-1-ethylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-propylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-butylpiperidinium Bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-hexylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl -1 heptylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-propylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-heptylpiperidinium bis (pentafluoroethane) Sulfonyl) imide, 1-ethyl-1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-hexylpiperidinium bis (pentafluoroethanesulponyl) imide, 1-ethyl-1- Heptylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-propyl-1-butylpiperidiniumbis (pentafluoroethanesulfonyl) imide, 1,1-dipropylpiperidiniumbis (pentafluoroethanesulfonyl) imide , 1,1-dibutylpiperidinium bis (pentafluoroethanesulfonyl) imide and the like.

Further, instead of the onium component of the above compound, trimethylsulfonium cation, triethylsulfonium cation, tributylsulfonium cation, trihexylsulfonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldecylsulfonium cation, tetramethylphosphonium cation, tetraethylphosphonium Examples thereof include cations, tetrabutylphosphonium cations, and compounds using tetrahexylphosphonium cations.

Further, instead of the above-mentioned bis (trifluoromethanesulfonyl) imide, bis (pentafluorosulfonyl) imide, bis (heptafluoropropanesulfonyl) imide, bis (nonafluorobutanesulfonyl) imide, trifluoromethanesulfonyl nonafluorobutanesulfonylimide, Examples thereof include compounds using heptafluoropropanesulfonyl trifluoromethanesulfonylimide, pentafluoroethane sulfonyl nonafluorobutane sulfonylimide, cyclo-hexafluoropropane-1,3-bis (sulfonyl) imide anion and the like.

The ratio of the onium-fluorine-containing imide anion salt (B) in the pressure-sensitive adhesive composition of the present invention is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the (meth) acrylic polymer (A). If the onium-fluorine-containing imide anion salt (B) is less than 0.1 parts by weight, the effect of improving the antistatic performance may not be sufficient. The onium-fluorine-containing imide anion salt (B) is preferably 0.2 parts by weight or more, more preferably 0.5 parts by weight or more. On the other hand, if the amount of the onium-fluorine-containing imide anion salt (B) is more than 10 parts by weight, the durability may not be sufficient. The onium-fluorine-containing imide anion salt (B) is preferably 5 parts by weight or less, preferably 3 parts by weight or less, and more preferably 2 parts by weight or less. The ratio of the onium-fluorine-containing imide anion salt (B) can be set in a preferable range by adopting the upper limit value or the lower limit value.

Further, the pressure-sensitive adhesive composition of the present invention may contain a cross-linking agent (C). As the cross-linking agent (C), an organic cross-linking agent or a polyfunctional metal chelate can be used. Examples of the organic cross-linking agent include isocyanate-based cross-linking agents, peroxide-based cross-linking agents, epoxy-based cross-linking agents, and imine-based cross-linking agents. A polyfunctional metal chelate is one in which a polyvalent metal is covalently or coordinated to an organic compound. Examples of the polyvalent metal atom include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, Ti and the like. Can be mentioned. Examples of the atom in the organic compound having a covalent bond or a coordination bond include an oxygen atom, and examples of the organic compound include an alkyl ester, an alcohol compound, a carboxylic acid compound, an ether compound, and a ketone compound.

As the cross-linking agent (C), an isocyanate-based cross-linking agent and / or a peroxide-type cross-linking agent is preferable. Examples of the compound related to the isocyanate-based cross-linking agent include isocyanate monomers such as tolylene diisocyanate, chlorphenylene diisocyanate, tetramethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, and hydrogenated diphenylmethane diisocyanate, and these isocyanate monomers. Examples include isocyanate compounds added with trimetylolpropane and the like, isocyanurates, bullet-type compounds, and urethane prepolymer-type isocyanates which have been subjected to an addition reaction such as polyether polyols, polyester polyols, acrylic polyols, polybutadiene polyols, and polyisoprene polyols. be able to. Particularly preferred is a polyisocyanate compound, which is one selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate, and isophorone diisocyanate, or a polyisocyanate compound derived thereto. Here, one selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate, and isophorone diisocyanate or a polyisocyanate compound derived thereto includes hexamethylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and polyol modification. Hexamethylene diisocyanate, polyol-modified hydrogenated xylylene diisocyanate, trimmer-type hydrogenated xylylene diisocyanate, polyol-modified isophorone diisocyanate and the like are included. The exemplified polyisocyanate compound is particularly preferable because the reaction with the hydroxyl group proceeds rapidly by using the acid and the base contained in the polymer as a catalyst, which contributes to the speed of cross-linking.

As the peroxide, any peroxide that generates radically active species by heating or light irradiation to promote cross-linking of the base polymer of the pressure-sensitive adhesive composition can be appropriately used, but in consideration of workability and stability. It is preferable to use a peroxide having a half-life temperature of 80 ° C. to 160 ° C. for 1 minute, and more preferably to use a peroxide having a half-life temperature of 90 ° C. to 140 ° C.

Examples of the peroxide that can be used include di (2-ethylhexyl) peroxydicarbonate (1 minute half-life temperature: 90.6 ° C.) and di (4-t-butylcyclohexyl) peroxydicarbonate (1). Minute half-life temperature: 92.1 ° C., di-sec-butylperoxydicarbonate (1 minute half-life temperature: 92.4 ° C.), t-butylperoxyneodecanoate (1 minute half-life temperature: 103) .5 ° C.), t-hexyl peroxypivalate (1 minute half-life temperature: 109.1 ° C.), t-butyl peroxypivalate (1 minute half-life temperature: 110.3 ° C.), dilauroyl peroxide (1 minute half-life temperature: 110.3 ° C.) 1 minute half temperature: 116.4 ° C), di-n-octanoyl peroxide (1 minute half temperature: 117.4 ° C), 1,1,3,3-tetramethylbutylperoxy-2-ethyl Hexanoate (1 minute half-life temperature: 124.3 ° C.), di (4-methylbenzoyl) peroxide (1 minute half-life temperature: 128.2 ° C.), dibenzoyl peroxide (1 minute half-life temperature: 130. 0 ° C.), t-Butylperoxyisobutyrate (1 minute half-life temperature: 136.1 ° C.), 1,1-di (t-hexylperoxy) cyclohexane (1 minute half-life temperature: 149.2 ° C.) And so on. Among them, di (4-t-butylcyclohexyl) peroxydicarbonate (1 minute half-life temperature: 92.1 ° C.) and dilauroyl peroxide (1 minute half-life temperature: 116.) Since the cross-linking reaction efficiency is particularly excellent. 4 ° C.), dibenzoylperoxide (1 minute half-life temperature: 130.0 ° C.) and the like are preferably used.

The half-life of peroxide is an index showing the decomposition rate of peroxide, and means the time until the residual amount of peroxide is halved. The decomposition temperature for obtaining a half-life at an arbitrary time and the half-life time at an arbitrary temperature are described in the manufacturer's catalog, etc. For example, "Organic peroxide catalog 9th edition" of Nippon Oil & Fats Co., Ltd. (May 2003) ”and so on.

The amount of the cross-linking agent (C) used is preferably 0.01 to 20 parts by weight, more preferably 0.03 to 10 parts by weight, based on 100 parts by weight of the (meth) acrylic polymer (A). If the amount of the cross-linking agent (C) is less than 0.01 parts by weight, the cohesive force of the adhesive tends to be insufficient and foaming may occur during heating. On the other hand, if it is more than 20 parts by weight, the moisture resistance is sufficient. Rather, peeling is likely to occur in reliability tests and the like.

The isocyanate-based cross-linking agent may be used alone or in combination of two or more, but the content as a whole is the (meth) acrylic polymer (A) 100. The polyisocyanate compound cross-linking agent is preferably contained in an amount of 0.01 to 2 parts by weight, more preferably 0.02 to 2 parts by weight, and 0.05 to 1.5 parts by weight. It is more preferably contained in parts by weight. It can be appropriately contained in consideration of cohesive force, prevention of peeling in durability test, and the like.

One type of the peroxide may be used alone, or two or more types may be mixed and used, but the content as a whole is 100 weight by weight of the (meth) acrylic polymer (A). The amount of the peroxide is 0.01 to 2 parts by weight, preferably 0.04 to 1.5 parts by weight, and more preferably 0.05 to 1 part by weight. .. It is appropriately selected within this range in order to adjust workability, reworkability, crosslink stability, peelability and the like.

As a method for measuring the amount of peroxide decomposition remaining after the reaction treatment, for example, HPLC (high performance liquid chromatography) can be used.

More specifically, for example, about 0.2 g of the pressure-sensitive adhesive composition after the reaction treatment is taken out, immersed in 10 ml of ethyl acetate, extracted by shaking at 120 rpm for 3 hours at 25 ° C. with a shaker, and then at room temperature. Let stand for 3 days. Next, 10 ml of acetonitrile was added, and the mixture was shaken at 120 rpm at 25 ° C. for 30 minutes, and about 10 μl of the extract obtained by filtering with a membrane filter (0.45 μm) was injected into HPLC for analysis. It can be the amount of peroxide.

Further, the pressure-sensitive adhesive composition of the present invention may contain a silane coupling agent (D). Durability can be improved by using the silane coupling agent (D). Specific examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2- (3, 4-Epoxycyclohexyl) Epoxy group-containing silane coupling agent such as ethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl- Amino group-containing silane coupling agents such as N- (1,3-dimethylbutylidene) propylamine and N-phenyl-γ-aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltri. Examples thereof include a (meth) acrylic group-containing silane coupling agent such as ethoxysilane, and an isocyanate group-containing silane coupling agent such as 3-isocyanatepropyltriethoxysilane.

The silane coupling agent (D) may be used alone or in combination of two or more, but the content as a whole is the (meth) acrylic polymer (A) 100. The silane coupling agent is preferably 0.001 to 5 parts by weight, more preferably 0.01 to 1 part by weight, still more preferably 0.02 to 1 part by weight, and further 0.05 by weight, based on parts by weight. ~ 0.6 parts by weight is preferable. It is an amount that improves durability and appropriately retains adhesive force to optical members such as liquid crystal cells.

Further, the pressure-sensitive adhesive composition of the present invention may contain a polyether-modified silicone compound. As the polyether-modified silicone compound, for example, those disclosed in JP-A-2010-275522 can be used.

The polyether-modified silicone compound has a polyether skeleton and has at least one terminal at the following general formula (1): -SiR _a M _3-a.
(In the formula, R is a monovalent organic group having 1 to 20 carbon atoms which may have a substituent, M is a hydroxyl group or a hydrolyzable group, and a is an integer of 0 to 2. However, when there are a plurality of Rs, the plurality of Rs may be the same or different from each other, and when there are a plurality of Ms, the plurality of Ms may be the same or different from each other.) It has a reactive silyl group represented.

The polyether-modified silicone compound includes
General formula (2): R _a M _3-a Si-XY- (AO) _n- Z
(In the formula, R is a monovalent organic group having 1 to 20 carbon atoms which may have a substituent, M is a hydroxyl group or a hydrolyzable group, and a is an integer of 0 to 2. However, when there are a plurality of Rs, the plurality of Rs may be the same or different from each other, and when there are a plurality of Ms, the plurality of Ms may be the same or different from each other. , A linear or branched oxyalkylene group having 1 to 10 carbon atoms, n being 1 to 1700, indicating the average number of moles of the oxyalkylene group added. X is a linear or branched chain having 1 to 20 carbon atoms. The alkylene group of the branched chain is shown. Y represents an ether bond, an ester bond, a urethane bond, or a carbonate bond.
Z is a hydrogen atom, a hydrocarbon group having 1 to 10 monovalent carbon atoms,
General formula (2A): -Y ^1- X-SiR _a M _3-a
(In the equation, R, M, X are the same as above. Y ¹ indicates a single bond, -CO- bond, -CONH- bond, or -COO- bond.) Or.
General formula (2B): -Q {-(OA) _n- Y-X-SiR _a M _3-a } _m
(In the formula, R, M, X, Y are the same as above. OA is the same as AO, n is the same as above. Q is a hydrocarbon group having 2 or more valences and having 1 to 10 carbon atoms. , M is the same as the valence of the hydrocarbon group). ) Is mentioned.

Specific examples of the polyether-modified silicone compound include MS polymers S203, S303, S810; SILYL EST250, EST280; SAT10, SAT200, SAT220, SAT350, SAT400 manufactured by Kaneka Corporation, and EXCESTAR S2410, S2420 or S3430 manufactured by Asahi Glass Co., Ltd. And so on.

Further, the pressure-sensitive adhesive composition of the present invention may contain other known additives, for example, a polyether compound of a polyalkylene glycol such as polypropylene glycol, a colorant, a powder such as a pigment, a dye, and the like. Surfactants, plasticizers, tackifiers, surface lubricants, leveling agents, softeners, antioxidants, antioxidants, light stabilizers, UV absorbers, polymerization inhibitors, inorganic or organic fillers, metals It can be appropriately added depending on the intended use of powder, particulate, foil or the like. Further, a redox system to which a reducing agent is added may be adopted within a controllable range.

A pressure-sensitive adhesive layer is formed by the pressure-sensitive adhesive composition. In forming the pressure-sensitive adhesive layer, it is necessary to adjust the amount of the entire cross-linking agent added and to fully consider the effects of the cross-linking treatment temperature and the cross-linking treatment time. preferable.

The cross-linking treatment temperature and the cross-linking treatment time can be adjusted depending on the cross-linking agent used. The crosslinking treatment temperature is preferably 170 ° C. or lower.

Further, the cross-linking treatment may be performed at the temperature at the time of the drying step of the pressure-sensitive adhesive layer, or a separate cross-linking treatment step may be provided after the drying step.

The cross-linking treatment time can be set in consideration of productivity and workability, but is usually about 0.2 to 20 minutes, preferably about 0.5 to 10 minutes.

In the polarizing film with an adhesive layer of the present invention, a transparent protective film is provided only on one side of the polarizer, and the pressure-sensitive adhesive layer is provided on the polarizing element by the pressure-sensitive adhesive composition without providing a transparent protective film on the other side. It is formed.

As a method of forming the pressure-sensitive adhesive layer, for example, a method of applying the pressure-sensitive adhesive composition to a separator or the like which has been peeled off, drying and removing a polymerization solvent or the like to form a pressure-sensitive adhesive layer, and then transferring the pressure-sensitive adhesive layer to a polarizing film, or a method of transferring the pressure-sensitive adhesive layer to a polarizing film. It is produced by a method of applying the pressure-sensitive adhesive composition to a polarizing film and drying and removing a polymerization solvent or the like to form a pressure-sensitive adhesive layer on the polarizing film. When applying the pressure-sensitive adhesive, one or more solvents other than the polymerization solvent may be newly added as appropriate.

A silicone release liner is preferably used as the release-treated separator. In the step of applying the adhesive composition of the present invention on such a liner and drying it to form a pressure-sensitive adhesive layer, as a method of drying the pressure-sensitive adhesive, an appropriate method is appropriately adopted depending on the purpose. obtain. Preferably, a method of heating and drying the coating film is used. The heating and drying temperature is preferably 40 ° C. to 200 ° C., more preferably 50 ° C. to 180 ° C., and particularly preferably 70 ° C. to 170 ° C. By setting the heating temperature in the above range, a pressure-sensitive adhesive having excellent adhesive properties can be obtained.

As the drying time, an appropriate time can be adopted as appropriate. The drying time is preferably 5 seconds to 20 minutes, more preferably 5 seconds to 10 minutes, and particularly preferably 10 seconds to 5 minutes.

Further, the pressure-sensitive adhesive layer can be formed after forming an anchor layer on the surface of the polarizing film or performing various easy-adhesion treatments such as corona treatment and plasma treatment. Further, the surface of the pressure-sensitive adhesive layer may be subjected to an easy-adhesion treatment.

Various methods are used as a method for forming the pressure-sensitive adhesive layer. Specifically, for example, roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, curtain coat, lip coat, die coater, etc. Examples include a method such as an extrusion coating method.

The thickness of the pressure-sensitive adhesive layer is not particularly limited, and is, for example, about 1 to 100 μm. It is preferably 2 to 50 μm, more preferably 2 to 40 μm, and even more preferably 5 to 35 μm.

When the pressure-sensitive adhesive layer is exposed, the pressure-sensitive adhesive layer may be protected by a sheet (separator) that has been peeled off until it is put into practical use.

Examples of the constituent material of the separator include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester film, porous materials such as paper, cloth, and non-woven fabric, nets, foam sheets, metal foils, and laminates thereof. A thin leaf body or the like can be mentioned, but a plastic film is preferably used because of its excellent surface smoothness.

The plastic film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, and vinyl chloride are all used. Examples thereof include a polymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film.

The thickness of the separator is usually about 5 to 200 μm, preferably about 5 to 100 μm. If necessary, the separator may be used for mold release and antifouling treatment with a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based mold release agent, silica powder, etc., as well as a coating type, a kneading type, and a vapor deposition type. It is also possible to perform antistatic treatment such as. In particular, the peelability from the pressure-sensitive adhesive layer can be further enhanced by appropriately performing a peeling treatment such as a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment on the surface of the separator.

The peeled sheet used in producing the above-mentioned polarizing film with an adhesive layer can be used as it is as a separator for the polarizing film with an adhesive layer, and the process can be simplified.

As the polarizing film, a polarizing film having a transparent protective film on only one side of the polarizing element is used.

The polarizer is not particularly limited, and various polarizers can be used. Examples of the polarizer include a hydrophilic polymer film such as a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, and an ethylene-vinyl acetate copolymerization system partially saponified film, and a bicolor property of iodine or a bicolor dye. Examples thereof include a uniaxially stretched film obtained by adsorbing a substance, a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol and a dehydrogenated product of polyvinyl chloride. Among these, a polarizer made of a polyvinyl alcohol-based film and a dichroic substance such as iodine is preferable. The thickness of these polarizers is not particularly limited, but is generally about 80 μm or less.

A polarizer in which a polyvinyl alcohol-based film is dyed with iodine and uniaxially stretched can be prepared, for example, by dyeing the polyvinyl alcohol-based film by immersing it in an aqueous solution of iodine and stretching it to 3 to 7 times the original length. can. If necessary, it can be immersed in an aqueous solution of potassium iodide or the like, which may contain boric acid, zinc sulfate, zinc chloride or the like. Further, if necessary, the polyvinyl alcohol-based film may be immersed in water and washed with water before dyeing. In addition to being able to clean the surface of the polyvinyl alcohol film and blocking inhibitors by washing the polyvinyl alcohol film with water, it also has the effect of preventing non-uniformity such as uneven dyeing by swelling the polyvinyl alcohol film. be. Stretching may be performed after dyeing with iodine, stretching while dyeing, or stretching and then dyeing with iodine. It can be stretched even in an aqueous solution such as boric acid or potassium iodide or in a water bath.

Further, as the polarizer, a thin polarizer having a thickness of 10 μm or less can be used. From the viewpoint of thinning, the thickness is preferably 1 to 7 μm. It is preferable that such a thin polarizing element has less uneven thickness, excellent visibility, excellent durability because there is little dimensional change, and the thickness of the polarizing film can be reduced. On the other hand, a thin polarizer is prone to polarization deterioration. In the polarizing film with a pressure-sensitive adhesive layer of the present invention, since the pressure-sensitive adhesive layer contains an onium-fluorine-containing imide anion salt (B), an antistatic function can be imparted without causing deterioration of optical characteristics. The polarizing film with an adhesive layer of the present invention can suppress a decrease in polarization characteristics even when a thin polarizing element is used.

Typical examples of the thin polarizing element include JP-A-51-069644, JP-A-2000-338329, WO2010 / 100917 pamphlet, PCT / JP2010 / 00146, or Japanese Patent Application No. 2010-. Examples thereof include the thin polarizing layer described in the specification of No. 269002 and the specification of Japanese Patent Application No. 2010-263692. These thin polarizing layers can be obtained by a manufacturing method including a step of stretching a polyvinyl alcohol-based resin (hereinafter, also referred to as PVA-based resin) layer and a resin base material for stretching in a laminated state and a step of dyeing. With this manufacturing method, even if the PVA-based resin layer is thin, it can be stretched without problems such as breakage due to stretching because it is supported by the stretching resin base material.

The thin polarizing layer can be stretched at a high magnification and the polarization performance can be improved even in a manufacturing method including a step of stretching in a laminated state and a step of dyeing. It is preferably obtained by a production method including a step of stretching in an aqueous boric acid solution as described in JP2010 / 00460, or in Japanese Patent Application No. 2010-269002 and Japanese Patent Application No. 2010-263692, particularly preferably. It is preferably obtained by a production method including a step of auxiliary stretching in the air before stretching in an aqueous boric acid solution described in Japanese Patent Application No. 2010-269002 and Japanese Patent Application No. 2010-263692.

The thin and high-performance polarizing layer described in the above description of PCT / JP2010 / 00160 is a thin thin resin having a thickness of 7 μm or less and made of a PVA-based resin in which a dichroic substance is oriented, which is integrally formed on a resin base material. It is a high-performance polarizing layer and has optical characteristics such as a single transmittance of 42.0% or more and a degree of polarization of 99.95% or more.

In the thin and high-performance polarizing layer, a PVA-based resin layer is formed by applying and drying a PVA-based resin on a resin base material having a thickness of at least 20 μm, and the generated PVA-based resin layer is used as a dyeing solution for a dichroic substance. Dichroic substance is adsorbed on the PVA-based resin layer by immersing in It can be produced by stretching so as to be 5 times or more of.

Further, it is a method for producing a laminated film including a thin and highly functional polarizing layer in which a bicolor substance is oriented, and contains a resin base material having a thickness of at least 20 μm and a PVA-based resin on one side of the resin base material. The laminate containing a step of producing a laminate film containing a PVA-based resin layer formed by applying and drying an aqueous solution, and a PVA-based resin layer formed on one side of the resin base material and the resin base material. A step of adsorbing a bicolor substance on a PVA-based resin layer contained in a laminated film by immersing the film in a dyeing solution containing a bicolor substance, and a PVA-based resin adsorbing the bicolor substance. The step of stretching the laminated film containing the layer so that the total draw ratio is 5 times or more of the original length in the boric acid aqueous solution, and the PVA-based resin layer on which the bicolor substance is adsorbed are the resin base material. The thickness is 7 μm or less, the single permeability is 42.0% or more, and the degree of polarization is 99. The thin and highly functional polarizing layer can be produced by including the step of producing a laminated film obtained by forming a thin and highly functional polarizing layer having an optical characteristic of .95% or more.

In the present invention, as described above, in the polarizing film with the pressure-sensitive adhesive layer, a polarizing layer of a continuous web made of a PVA-based resin in which a dichroic substance is oriented as a polarizer having a thickness of 10 μm or less is provided with heat. A laminate obtained by stretching a laminate containing a polyvinyl alcohol-based resin layer formed on a plastic resin base material in a two-step stretching step consisting of aerial auxiliary stretching and boric acid water stretching can be used. As the thermoplastic resin base material, an amorphous ester-based thermoplastic resin base material or a crystalline ester-based thermoplastic resin base material is preferable.

The thin polarizing layer of Japanese Patent Application No. 2010-269002 and Japanese Patent Application No. 2010-263692 is a continuous web polarizing layer made of a PVA-based resin in which a dichroic substance is oriented, and is amorphous. The laminate containing the PVA-based resin layer formed on the ester-based thermoplastic resin base material was stretched in a two-step stretching step consisting of aerial auxiliary stretching and boric acid water stretching to obtain a thickness of 10 μm or less. It is a thing. In such a thin polarizing layer, when the simple substance transmittance is T and the degree of polarization is P, P> − (10 ^{0.929 T-42.4} -1) × 100 (where T <42.3), and P ≧ It is preferable that the material has optical characteristics that satisfy the condition of 99.9 (however, T ≧ 42.3).

Specifically, the thin polarizing layer is a stretching intermediate composed of a PVA-based resin layer oriented by high-temperature stretching in the air with respect to a PVA-based resin layer formed on a continuous web amorphous ester-based thermoplastic resin base material. Colored intermediate formation consisting of a PVA-based resin layer in which a dichroic substance (preferably iodine or a mixture of iodine and an organic dye) is oriented by a step of producing a product and adsorption of the dichroic substance to the stretching intermediate product. A thin polarizing layer including a step of forming a substance and a step of forming a polarizing layer having a thickness of 10 μm or less composed of a PVA-based resin layer in which a dichroic substance is oriented by stretching in boric acid with respect to a colored intermediate product. It can be manufactured by the manufacturing method of.

In this production method, the total draw ratio of the PVA-based resin layer formed on the amorphous ester-based thermoplastic resin base material by high-temperature stretching in the air and stretching in water boric acid is set to 5 times or more. desirable. The liquid temperature of the boric acid aqueous solution for stretching in boric acid water can be 60 ° C. or higher. Before stretching the colored intermediate product in the boric acid aqueous solution, it is desirable to insolubilize the colored intermediate product. In that case, the colored intermediate product is added to the boric acid aqueous solution whose liquid temperature does not exceed 40 ° C. It is desirable to do this by immersing. The amorphous ester-based thermoplastic resin base material is an amorphous polyethylene containing copolymerized polyethylene terephthalate copolymerized with isophthalic acid, copolymerized polyethylene terephthalate copolymerized with cyclohexanedimethanol, or other copolymerized polyethylene terephthalate. It can be made of terephthalate, preferably made of a transparent resin, and its thickness can be 7 times or more the thickness of the PVA-based resin layer to be formed. The stretching ratio of the high-temperature stretching in the air is preferably 3.5 times or less, and the stretching temperature of the high-temperature stretching in the air is preferably equal to or higher than the glass transition temperature of the PVA-based resin, specifically in the range of 95 ° C to 150 ° C. When high-temperature stretching in the air is performed by free-end uniaxial stretching, the total stretching ratio of the PVA-based resin layer formed on the amorphous ester-based thermoplastic resin base material is preferably 5 times or more and 7.5 times or less. .. Further, when high-temperature stretching in the air is performed by uniaxial stretching at a fixed end, the total stretching ratio of the PVA-based resin layer formed on the amorphous ester-based thermoplastic resin base material is 5 times or more and 8.5 times or less. Is preferable.
More specifically, the thin polarizing layer can be manufactured by the following method.

A continuous web substrate of isophthalic acid copolymerized polyethylene terephthalate (amorphous PET) obtained by copolymerizing 6 mol% of isophthalic acid is prepared. The glass transition temperature of amorphous PET is 75 ° C. A laminate composed of an amorphous PET substrate of a continuous web and a polyvinyl alcohol (PVA) layer is prepared as follows. Incidentally, the glass transition temperature of PVA is 80 ° C.

An amorphous PET substrate having a thickness of 200 μm and a PVA aqueous solution having a degree of polymerization of 1000 or more and a PVA powder having a degree of polymerization of 99% or more dissolved in water and having a concentration of 4 to 5% are prepared. Next, a PVA aqueous solution is applied to a 200 μm-thick amorphous PET base material and dried at a temperature of 50 to 60 ° C. to obtain a laminate in which a 7 μm-thick PVA layer is formed on the amorphous PET base material. ..

A thin, high-performance polarizing layer having a thickness of 3 μm is produced from a laminate containing a PVA layer having a thickness of 7 μm through the following steps including a two-step stretching step of auxiliary stretching in the air and stretching in boric acid in water. By the first-stage aerial auxiliary stretching step, the laminated body containing the PVA layer having a thickness of 7 μm is stretched integrally with the amorphous PET substrate to produce a stretched laminated body containing the PVA layer having a thickness of 5 μm. Specifically, this stretched laminate is subjected to a stretching device provided in an oven set to a stretching temperature environment of 130 ° C. to obtain a stretching ratio of 1.8 times. It is stretched uniaxially at the free end. By this stretching treatment, the PVA layer contained in the stretched laminate is changed into a 5 μm-thick PVA layer in which PVA molecules are oriented.

Next, the dyeing step produces a colored laminate in which iodine is adsorbed on a 5 μm-thick PVA layer in which PVA molecules are oriented. Specifically, in this colored laminate, the stretched laminate is made into a dyeing solution containing iodine and potassium iodide at a liquid temperature of 30 ° C., and the single transmittance of the PVA layer constituting the highly functional polarizing layer finally produced is obtained. Iodine is adsorbed on the PVA layer contained in the stretched laminate by immersing it for an arbitrary time so that the content is 40 to 44%. In this step, the dyeing solution uses water as a solvent and has an iodine concentration in the range of 0.12 to 0.30% by weight and a potassium iodide concentration in the range of 0.7 to 2.1% by weight. The ratio of iodine to potassium iodide concentrations is 1: 7. By the way, potassium iodide is required to dissolve iodine in water. More specifically, by immersing the stretched laminate in a dyeing solution having an iodine concentration of 0.30% by weight and a potassium iodide concentration of 2.1% by weight for 60 seconds, iodine was added to a 5 μm-thick PVA layer in which PVA molecules were oriented. To produce a colored laminate in which iodine is adsorbed.

Further, by the second step of stretching in boric acid in water, the colored laminate is further stretched integrally with the amorphous PET substrate to generate an optical film laminate containing a PVA layer constituting a highly functional polarizing layer having a thickness of 3 μm. do. Specifically, this optical film laminate is stretched by subjecting the colored laminate to a stretching device installed in a processing device set in a boric acid aqueous solution having a liquid temperature range of 60 to 85 ° C. containing boric acid and potassium iodide. It is stretched uniaxially at the free end so that the magnification is 3.3 times. More specifically, the liquid temperature of the boric acid aqueous solution is 65 ° C. It also has a boric acid content of 4 parts by weight with respect to 100 parts by weight of water and a potassium iodide content of 5 parts by weight with respect to 100 parts by weight of water. In this step, the colored laminate having an adjusted iodine adsorption amount is first immersed in a boric acid aqueous solution for 5 to 10 seconds. After that, the colored laminate is passed as it is between a plurality of sets of rolls having different peripheral speeds, which is a stretching device deployed in the processing device, and the stretching ratio is freely increased to 3.3 times over 30 to 90 seconds. Stretch uniaxially. By this stretching treatment, the PVA layer contained in the colored laminate is changed into a 3 μm-thick PVA layer in which the adsorbed iodine is highly oriented in one direction as a polyiodine ion complex. This PVA layer constitutes a highly functional polarizing layer of an optical film laminate.

Although not an essential step in the production of the optical film laminate, the optical film laminate was taken out from the boric acid aqueous solution by the cleaning step and adhered to the surface of the 3 μm-thick PVA layer formed on the amorphous PET substrate. It is preferable to wash boric acid with an aqueous solution of potassium iodide. After that, the washed optical film laminate is dried by a drying step with warm air at 60 ° C. The cleaning step is a step for eliminating appearance defects such as boric acid precipitation.

Similarly, although it is not an essential process for producing an optical film laminate, an adhesive is applied to the surface of a 3 μm-thick PVA layer formed on an amorphous PET substrate by a bonding and / or transfer process. However, after the 80 μm-thick triacetyl cellulose film is attached, the amorphous PET substrate can be peeled off and the 3 μm-thick PVA layer can be transferred to the 80 μm-thick triacetyl cellulose film.

[Other processes]
The method for producing the thin polarizing layer may include other steps in addition to the above steps. Examples of other steps include an insolubilization step, a cross-linking step, a drying (adjustment of water content) step, and the like. Other steps can be performed at any suitable timing.
The insolubilization step is typically performed by immersing a PVA-based resin layer in an aqueous boric acid solution. By applying the insolubilization treatment, water resistance can be imparted to the PVA-based resin layer. The concentration of the boric acid aqueous solution is preferably 1 part by weight to 4 parts by weight with respect to 100 parts by weight of water. The liquid temperature of the insolubilizing bath (boric acid aqueous solution) is preferably 20 ° C to 50 ° C. Preferably, the insolubilization step is performed after the laminate is prepared and before the dyeing step and the underwater stretching step.
The above-mentioned cross-linking step is typically performed by immersing a PVA-based resin layer in an aqueous boric acid solution. Water resistance can be imparted to the PVA-based resin layer by subjecting it to a cross-linking treatment. The concentration of the boric acid aqueous solution is preferably 1 part by weight to 4 parts by weight with respect to 100 parts by weight of water. Further, when the cross-linking step is performed after the dyeing step, it is preferable to further add iodide. By blending iodide, the elution of iodine adsorbed on the PVA-based resin layer can be suppressed. The blending amount of iodide is preferably 1 part by weight to 5 parts by weight with respect to 100 parts by weight of water. Specific examples of iodide are as described above. The liquid temperature of the crosslinked bath (boric acid aqueous solution) is preferably 20 ° C. to 50 ° C. Preferably, the cross-linking step is performed before the second boric acid water stretching step. In a preferred embodiment, the dyeing step, the cross-linking step, and the second boric acid water stretching step are performed in this order.

As a material constituting the transparent protective film, for example, a thermoplastic resin having excellent transparency, mechanical strength, thermal stability, moisture blocking property, isotropic property and the like is used. Specific examples of such thermoplastic resins include cellulose resins such as triacetyl cellulose, polyester resins, polyether sulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, (meth) acrylic resins, and cyclic resins. Examples thereof include polyolefin resins (norbornene-based resins), polyarylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures thereof. The transparent protective film may contain one or more of any suitable additives. Examples of the additive include an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, a color retardant, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a colorant and the like. The content of the thermoplastic resin in the transparent protective film is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, still more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. .. When the content of the thermoplastic resin in the transparent protective film is 50% by weight or less, the high transparency inherent in the thermoplastic resin may not be sufficiently exhibited.

A transparent protective film is attached to one side of the polarizer by an adhesive layer. An adhesive is used for the bonding process between the polarizer and the transparent protective film. Examples of the adhesive include isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, and water-based polyesters. The adhesive is usually used as an adhesive consisting of an aqueous solution, and usually contains 0.5 to 60% by weight of a solid content. In addition to the above, examples of the adhesive between the polarizer and the transparent protective film include an ultraviolet curable adhesive and an electron beam curable adhesive. The adhesive for an electron beam curable polarizing film exhibits suitable adhesiveness to the above-mentioned various transparent protective films. Further, the adhesive used in the present invention may contain a metal compound filler.

Further, the polarizing film can be laminated with another optical film. Other optical films include, for example, for forming liquid crystal display devices such as reflectors, antitransparent plates, retardation films (including wave plates such as 1/2 and 1/4), visual compensation films, and brightness improving films. Examples include those that are optical layers that may be used. These can be laminated on the polarizing film in practical use and used as one layer or two or more layers.

An optical film in which the optical layer is laminated on a polarizing film can also be formed by a method of sequentially and separately laminating in a manufacturing process of a liquid crystal display or the like, but a pre-laminated optical film is of good quality. It is excellent in stability and assembly work, and has the advantage of being able to improve the manufacturing process of liquid crystal displays and the like. An appropriate adhesive means such as an adhesive layer can be used for laminating. When the above-mentioned polarizing film and other optical layers are adhered to each other, their optical axes can be arranged at an appropriate arrangement angle according to a target phase difference characteristic or the like.

The polarizing film with an adhesive layer of the present invention can be preferably used for forming various image display devices such as a liquid crystal display device. The liquid crystal display device can be formed according to the conventional method. That is, a liquid crystal display device is generally formed by appropriately assembling a display panel such as a liquid crystal cell, a polarizing film with an adhesive layer, and if necessary, components such as a lighting system, and incorporating a drive circuit. The present invention is not particularly limited except that the polarizing film with the pressure-sensitive adhesive layer according to the present invention is used, and can be the same as the conventional one. As the liquid crystal cell, any type such as TN type, STN type, π type, VA type, IPS type and the like can be used.

It is possible to form an appropriate liquid crystal display device such as a liquid crystal display device in which a polarizing film with an adhesive layer is arranged on one side or both sides of a display panel such as a liquid crystal cell, or a lighting system using a backlight or a reflector. .. In that case, the polarizing film with an adhesive layer according to the present invention can be installed on one side or both sides of a display panel such as a liquid crystal cell. When the optical films are provided on both sides, they may be the same or different. Further, when forming the liquid crystal display device, for example, an appropriate component such as a diffusion layer, an anti-glare layer, an antireflection film, a protective plate, a prism array, a lens array sheet, a light diffusion sheet, and a backlight is placed in one layer or at an appropriate position. Two or more layers can be arranged.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. In addition, each part and% in each example is based on weight. All the conditions for leaving at room temperature, which are not specified below, are 23 ° C. and 65% RH.

<Measurement of weight average molecular weight of (meth) acrylic polymer (A)>
The weight average molecular weight of the (meth) acrylic polymer (A) was measured by GPC (gel permeation chromatography).
-Analyzer: HLC-8120GPC manufactured by Tosoh Corporation
-Column: Made by Tosoh, G7000H _XL + GMH _XL + GMH _XL
-Column size: 7.8 mm φ x 30 cm each 90 cm in total
-Column temperature: 40 ° C
・ Flow rate: 0.8 ml / min
・ Injection amount: 100 μl
-Eluent: Tetrahydrofuran-Detector: Differential refractometer (RI)
・ Standard sample: Polystyrene

<Creation of polarizing film (1)>
In order to prepare a thin polarizing layer, first, a laminated body in which a 9 μm-thick PVA layer is formed on an amorphous PET substrate is subjected to aerial auxiliary stretching at a stretching temperature of 130 ° C. to form a stretched laminated body, and then stretched. A colored laminate is produced by dyeing the laminate, and the colored laminate is further stretched integrally with the amorphous PET substrate by stretching in boric acid water at a stretching temperature of 65 ° C so that the total stretching ratio becomes 5.94 times. An optical film laminate containing a PVA layer having a thickness of 4 μm was produced. The PVA molecules in the PVA layer formed on the amorphous PET substrate by such two-step stretching are highly oriented, and the iodine adsorbed by dyeing is highly oriented in one direction as a polyiodine ion complex. It was possible to generate an optical film laminate containing a PVA layer having a thickness of 4 μm, which constitutes a highly functional polarizing layer. Further, while applying a polyvinyl alcohol-based adhesive to the surface of the polarizing layer of the optical film laminate, a saponified 40 μm-thick triacetyl cellulose film is attached, and then the amorphous PET base material is peeled off. A polarizing film using a thin polarizing layer was produced. Hereinafter, this is referred to as a thin polarizing film (1).

<Creation of polarizing film (2)>
A polyvinyl alcohol film having a thickness of 80 μm was dyed between rolls having different speed ratios in an iodine solution at 30 ° C. and a concentration of 0.3% for 1 minute, and stretched up to 3 times. Then, the total stretching ratio was stretched to 6 times while being immersed in an aqueous solution containing boric acid having a concentration of 4% and potassium iodide having a concentration of 10% at 60 ° C. for 0.5 minutes. Then, it was washed by immersing it in an aqueous solution containing potassium iodide having a concentration of 1.5% at 30 ° C. for 10 seconds, and then dried at 50 ° C. for 4 minutes to obtain a polarizer having a thickness of 20 μm. A saponified 40 μm-thick triacetyl cellulose film was bonded to one side of the polarizing element with a polyvinyl alcohol-based adhesive to prepare a polarizing film. Hereinafter, this is referred to as a TAC-based polarizing film (2).

Manufacturing example 1
<Preparation of acrylic polymer (A-1)>
A four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler was charged with a monomer mixture containing 99 parts of butyl acrylate and 1 part of 4-hydroxybutyl acrylate. Further, 0.1 part of 2,2'-azobisisobutyronitrile was charged together with ethyl acetate as a polymerization initiator with respect to 100 parts of the monomer mixture (solid content), and nitrogen gas was introduced while gently stirring. After substituting with nitrogen, the liquid temperature in the flask was maintained at around 60 ° C. and the polymerization reaction was carried out for 7 hours. Then, ethyl acetate was added to the obtained reaction solution to prepare a solution of an acrylic polymer (A-1) having a weight average molecular weight of 1.4 million adjusted to a solid content concentration of 30%.

Manufacturing example 2
<Preparation of acrylic polymer (A-2)>
A monomer mixture containing 99 parts of butyl acrylate, 0.5 parts of 2-hydroxyethyl acrylate and 0.5 parts of acrylic acid was placed in a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler. I prepared it. Further, 0.1 part of 2,2'-azobisisobutyronitrile was charged together with ethyl acetate as a polymerization initiator with respect to 100 parts of the monomer mixture (solid content), and nitrogen gas was introduced while gently stirring. After substituting with nitrogen, the liquid temperature in the flask was maintained at around 60 ° C. and the polymerization reaction was carried out for 7 hours. Then, ethyl acetate was added to the obtained reaction solution to prepare a solution of an acrylic polymer (A-2) having a weight average molecular weight of 1.4 million adjusted to a solid content concentration of 30%.

Example 1
(Preparation of adhesive composition)
0.2 part of (B-1) trimethylpropylammonylbis (trifluoromethanesulfonyl) imide (manufactured by Tokyo Kasei Kogyo) with respect to 100 parts of the solid content of the acrylic polymer (A-1) solution obtained in Production Example 1. (C-1) Trimethylolpropoxylylene diisocyanate (manufactured by Mitsui Chemicals Co., Ltd .: Takenate D110N) 0.1 part, (C-1) dibenzoyl peroxide 0.3 part, and (D- 1) 0.075 parts of γ-glycidoxypropylmethoxysilane (manufactured by Shinetsu Chemical Industry Co., Ltd .: KBM-403) was blended to prepare an acrylic pressure-sensitive adhesive solution.

(Preparation of polarizing film with adhesive layer)
Next, the above-mentioned acrylic pressure-sensitive adhesive solution was uniformly applied to the surface of a polyethylene terephthalate film (separator film) treated with a silicone-based release agent with a fountain coater, and dried in an air circulation type constant temperature oven at 155 ° C. for 2 minutes. Then, a pressure-sensitive adhesive layer having a thickness of 20 μm was formed on the surface of the separator film. Next, the pressure-sensitive adhesive layer formed on the separator film was transferred to the side of the polarizing layer of the polarizer of the thin polarizing film (1) prepared above to prepare a polarizing film with a pressure-sensitive adhesive layer.

Examples 2 to 20, Comparative Examples 1 to 4
In Example 1, in preparing the pressure-sensitive adhesive composition, the type or amount of each component was changed as shown in Table 1, and in preparing the polarizing film with the pressure-sensitive adhesive layer, the types of the polarizing film are shown in Table 1. A polarizing film with an adhesive layer was produced in the same manner as in Example 1 except that the film was changed to.

The following evaluations were performed on the polarizing films with an adhesive layer obtained in the above Examples and Comparative Examples. The evaluation results are shown in Table 1.

<Surface resistance value: initial>
After peeling off the separator film of the polarizing film with the pressure-sensitive adhesive layer, the surface resistance value (Ω / □) of the pressure-sensitive adhesive surface was measured using MCP-HT450 manufactured by Mitsubishi Chemical Analytech.

<Evaluation of static electricity unevenness>
The produced polarizing film with an adhesive layer was cut into a size of 100 mm × 100 mm and attached to a liquid crystal panel. This panel was placed on a backlight having a brightness of 10000 cd, and the orientation of the liquid crystal was disturbed by generating static electricity of 5 kv using an ESD generator (ESD-8012A manufactured by SANKI). The recovery time (seconds) of the display defect due to the misalignment was measured using an instantaneous multi-photometric detector (MCPD-3000 manufactured by Otsuka Electronics Co., Ltd.) and evaluated according to the following criteria.
⊚: The display defect disappeared in less than 1 second.
◯: The display defect disappeared in 1 second or more and less than 10 seconds.
X: The display defect disappeared in 10 seconds or more.

<Durability>
The separator film of the polarizing film with the pressure-sensitive adhesive layer was peeled off and attached to a 0.7 mm-thick non-alkali glass (1737 manufactured by Corning Inc.) using a laminator. Next, an autoclave treatment was performed at 50 ° C. and 5 atm for 15 minutes to completely adhere the polarizing film with the pressure-sensitive adhesive layer to the non-alkali glass. Next, this was put under the conditions of a heating oven (heating) at 80 ° C. and a constant temperature / humidifier (humidifying) at 60 ° C./90% RH, and the presence or absence of peeling of the polarizing film after 500 hours was checked as follows. Evaluated by criteria.
⊚: No peeling was observed.
◯: Peeling that could not be visually confirmed was observed.
Δ: Small peeling that can be visually confirmed was observed.
X: Clear peeling was observed.

<Measurement of degree of polarization>
The separator film of the polarizing film with an adhesive layer was peeled off and attached to a 0.7 mm-thick non-alkali glass (1737 manufactured by Corning Inc.) using a laminator. Next, an autoclave treatment was performed at 50 ° C. and 0.5 MPa for 15 minutes to completely adhere the polarizing film with the pressure-sensitive adhesive layer to the non-acrylic glass. Then, it was put into a constant temperature and humidity chamber at 60 ° C./90% RH for 500 hours. The degree of polarization of the polarizing film before and after the addition was measured using V7100 manufactured by JASCO Corporation, and the amount of change ΔP = (degree of polarization before addition)-(degree of polarization after addition) was determined. ..

Claims (17)

A polarizing film with a pressure-sensitive adhesive layer having a polarizing film and a pressure-sensitive adhesive layer provided on the polarizing film.
The polarizing film has a transparent protective film on only one side of the polarizer, the pressure-sensitive adhesive layer is provided on the polarizer on the side that does not have the transparent protective film, and the pressure-sensitive adhesive layer is (meth. ) The onium-fluorine-containing imide anion salt (B) containing the acrylic polymer (A) and the onium-fluorine-containing imide anion salt (B) , and based on 100 parts by weight of the (meth) acrylic polymer (A). It is formed from a pressure-sensitive adhesive composition containing 0.1 to 10 parts by weight of B).
The polarizing film with an adhesive layer is determined from the degree of polarization (%) measured before and after 500 hours of charging into a constant temperature and humidity chamber at 60 ° C./90% RH.
Equation: Change amount (%) ΔP = (Polarization degree before charging (%))-(Polarization degree after charging (%))
A polarizing film with an adhesive layer, wherein the amount of change (%) ΔP represented by is satisfied with 0.13 or less. The polarized light with a pressure-sensitive adhesive layer according to claim 1, wherein the onium in the onium-fluorine-containing imide anion salt (B) is at least one selected from nitrogen-containing onium, sulfur-containing onium, and phosphorus-containing onium. the film. The polarizing film with an adhesive layer according to claim 2, wherein the onium in the onium-fluorine-containing imide anion salt (B) is at least one selected from ammonium, pyrrolidinium, piperidinium and sulfonium. The polarizing film with an adhesive layer according to any one of claims 1 to 3, wherein the onium in the onium-fluorine-containing imide anion salt (B) does not have an unsaturated bond. The polarized light with a pressure-sensitive adhesive layer according to any one of claims 1 to 4, wherein the onium in the onium-fluorine-containing imide anion salt (B) is an alkyl onium having an alkyl group having 1 to 4 carbon atoms. the film. The polarizing film with an adhesive layer according to any one of claims 1 to 5 , wherein the (meth) acrylic polymer (A) contains an alkyl (meth) acrylate and a hydroxyl group-containing monomer as a monomer unit. .. The polarizing film with an adhesive layer according to any one of claims 1 to 6 , wherein the (meth) acrylic polymer (A) contains an alkyl (meth) acrylate and a carboxyl group-containing monomer as a monomer unit. .. The polarizing film with a pressure-sensitive adhesive layer according to any one of claims 1 to 7 , wherein the pressure-sensitive adhesive composition further contains a cross-linking agent (C). The polarizing film with an adhesive layer according to claim 8, wherein the cross-linking agent (C) is contained in an amount of 0.01 to 20 parts by weight with respect to 100 parts by weight of the (meth) acrylic polymer (A). The polarizing film with an adhesive layer according to claim 8 or 9, wherein the cross-linking agent (C) is at least one selected from an isocyanate compound and a peroxide. The invention according to any one of claims 1 to 10 , wherein the silane coupling agent (D) is further contained in an amount of 0.001 to 5 parts by weight based on 100 parts by weight of the (meth) acrylic polymer (A). Polarizing film with adhesive layer. The adhesive according to any one of claims 1 to 11 , further comprising 0.001 to 10 parts by weight of the polyether-modified silicone compound with respect to 100 parts by weight of the (meth) acrylic polymer (A). Polarizing film with agent layer. The polarizing film with an adhesive layer according to any one of claims 1 to 12 , wherein the (meth) acrylic polymer (A) has a weight average molecular weight of 500,000 to 3,000,000. The polarizing film with an adhesive layer according to any one of claims 1 to 13 , wherein an easy-adhesive layer is provided between the polarizing film and the adhesive layer. A method of imparting an antistatic function without causing deterioration of a polarizer by attaching the polarizing film with an adhesive layer according to any one of claims 1 to 14 to a liquid crystal panel. The method for producing a polarizing film with an adhesive layer according to any one of claims 1 to 14.
A continuous web polarizing film made of a polyvinyl alcohol-based resin in which a dichroic substance is oriented, and a laminate containing a polyvinyl alcohol-based resin layer formed on a thermoplastic resin base material is subjected to aerial auxiliary stretching and boric acid water. A step of preparing a polarizer having a thickness of 10 μm or less obtained by stretching in a two-step stretching step consisting of stretching.
A step of obtaining a polarizing film by a step of attaching a transparent protective film only to one side of the polarizer,
A (meth) acrylic polymer (A) and an onium-fluorine-containing imide anion salt (B) were added to the step of peeling the thermoplastic resin base material and the polarizer of the polarizing film on the side not having the transparent protective film. A method for producing a polarizing film with a pressure-sensitive adhesive layer, which comprises a step of forming a pressure-sensitive adhesive layer with the pressure-sensitive adhesive composition contained therein. An image display device using at least one polarizing film with an adhesive layer according to any one of claims 1 to 13.