KR102568075B1 - Optical laminate and liquid crystal display device - Google Patents

Abstract

The present invention includes an optical film, an adhesive layer, and a metal layer in this order, the metal layer is a metal wiring layer, and the adhesive layer is a (meth)acrylic resin (A), an isocyanate-based crosslinking agent (B), a silane compound ( C) and an ionic compound (D) represented by the formula: M ⁺ X ^- (M ⁺ represents an inorganic cation, X ^- represents a fluorine atom-containing anion), the pressure-sensitive adhesive composition comprising: ) Contains 0.01 to 2.5 parts by weight of an isocyanate-based crosslinking agent (B), 0.01 to 10 parts by weight of a silane compound (C), and 0.2 to 8 parts by weight of an ionic compound (D) based on 100 parts by weight of the acrylic resin (A). It is an object of the present invention to provide an optical layered body to do, and a liquid crystal display device including the same.

Description

Optical laminate and liquid crystal display {OPTICAL LAMINATE AND LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to an optical laminate constituting an image display device such as a liquid crystal display device, and a liquid crystal display device including the same.

An optical film typified by a polarizing plate formed by laminating and bonding a transparent resin film on one side or both sides of a polarizer is widely used as an optical member constituting an image display device such as a liquid crystal display device. An optical film such as a polarizing plate is often used by being bonded to another member (for example, a liquid crystal cell in a liquid crystal display device) through an adhesive layer (see, for example, Japanese Unexamined Patent Publication No. 2010-229321). For this reason, as an optical film, the optical film with an adhesive layer in which the adhesive layer was previously formed in the one surface is known. It is also known that the pressure-sensitive adhesive layer contains an ionic compound so as to impart antistatic properties.

In recent years, liquid crystal display devices have been developed for use in mobile devices having a touch panel function, typified by smart phones, tablet terminals, and in-vehicle car navigation systems. In such a touch input type liquid crystal display device, the pressure-sensitive adhesive layer of the optical film with a pressure-sensitive adhesive layer may be disposed so as to contact a metal layer composed of metal wiring, for example, via a resin layer or directly. However, in a configuration in which a metal layer made of a metal material and an adhesive layer containing an ionic compound are combined, the metal layer may be corroded in a high-temperature, high-humidity environment. Among corrosion, pitting is a particular problem because the metal layer penetrates when the thickness of the metal layer is thin or when the line width is narrow when the metal layer is a metal wiring.

An object of the present invention is to provide an optical laminate in which an optical film with an adhesive layer is laminated on a metal layer such as a metal wiring layer, and which can suppress corrosion of the metal layer, and a liquid crystal display device including the same. .

The present invention provides an optical laminate shown below, a liquid crystal display device containing the same, and an adhesive composition.

[1] An optical film, an adhesive layer, and a metal layer are included in this order,

The pressure-sensitive adhesive layer is composed of a pressure-sensitive adhesive composition containing a (meth)acrylic resin (A), an isocyanate-based crosslinking agent (B), a silane compound (C), and an ionic compound (D) represented by the following formula (I),

The pressure-sensitive adhesive composition contains 0.01 to 2.5 parts by weight of the isocyanate-based crosslinking agent (B), 0.01 to 10 parts by weight of the silane compound (C), and the ionic compound, based on 100 parts by weight of the (meth)acrylic resin (A). An optical laminate comprising 0.2 to 8 parts by weight of compound (D).

M ⁺ X ^- (I)

(In formula (I), M ⁺ represents an inorganic cation, and X ^- represents a fluorine atom-containing anion.)

[2] The optical laminate according to [1], wherein the inorganic cation is an alkali metal cation or an alkaline earth metal cation.

[3] The optical laminate according to [1] or [2], wherein the alkali metal cation is a lithium cation [Li ⁺ ], a potassium cation [K ⁺ ], or a sodium cation [Na ⁺ ].

[4] The optical laminate according to [1] or [2], wherein the alkali metal cation is a potassium cation [K ⁺ ].

[5] The optical laminate according to any one of [1] to [4], wherein the fluorine atom-containing anion is a fluorine atom-containing anion represented by the following formula (II).

[Y(SO ₂ C _m F _2m+1 ) _n ] ^- (II)

(In formula (II), Y represents a carbon atom or a nitrogen atom, n is 3 when Y is a carbon atom, n is 2 when Y is a nitrogen atom, and m represents an integer from 0 to 10.)

[6] The fluorine atom-containing anion is a bis(fluorosulfonyl)imide anion [(FSO ₂ ) ₂ N ^- ] or a bis(trifluoromethanesulfonyl)imide anion [(CF ₃ SO ₂ ) ₂ The optical laminate according to any one of [1] to [5], which is N ^- ].

[7] The optical laminate according to any one of [1] to [5], wherein the fluorine atom-containing anion is a bis(fluorosulfonyl)imide anion [(FSO ₂ ) ₂ N ^- ].

[8] The (meth)acrylic resin (A) is a constituent unit derived from an alkyl acrylate (a1) having a homopolymer glass transition temperature of less than 0 ° C. and an alkyl acrylate having a homopolymer glass transition temperature of 0 ° C. or higher (a2 ) The optical laminate according to any one of [1] to [7], containing a structural unit derived from.

[9] In the (meth)acrylic resin (A), the content of the structural unit derived from the alkyl acrylate (a2) is 10 parts by weight out of 100 parts by weight of the total structural units constituting the (meth)acrylic resin (A). The optical laminate according to [8], which is at least part.

[10] The optical laminate according to [8] or [9], wherein the alkyl acrylate (a2) contains methyl acrylate.

[11] The optical laminate according to any one of [1] to [10], wherein the (meth)acrylic resin (A) contains a constituent unit derived from a monomer having a hydroxyl group.

[12] The optical laminate according to any one of [1] to [11], wherein the (meth)acrylic resin (A) does not substantially contain a constituent unit derived from a monomer having a carboxyl group.

[13] The pressure-sensitive adhesive composition includes a triazole-based compound, a thiazole-based compound, an imidazole-based compound, an imidazoline-based compound, a quinoline-based compound, a pyridine-based compound, a pyrimidine-based compound, an indole-based compound, an amine-based compound, and a urea-based compound. The optical laminate according to any one of [1] to [12], which does not substantially contain a rust inhibitor selected from the group consisting of compounds, sodium benzoate, benzyl mercapto-based compounds, di-sec-butyl sulfide, and diphenyl sulfoxide. sifter.

[14] The metal layer is one or more selected from the group consisting of aluminum, copper, silver, iron, tin, zinc, nickel, molybdenum, chromium, tungsten, lead, and an alloy containing two or more metals selected from these. The optical laminate according to any one of [1] to [13] including.

[15] The optical laminate according to any one of [1] to [14], wherein the metal layer contains an aluminum element.

[16] The optical laminate according to any one of [1] to [15], wherein the metal layer is a layer formed by sputtering.

[17] The optical laminate according to any one of [1] to [16], wherein the metal layer has a thickness of 3 μm or less.

[18] A liquid crystal display device comprising the optical laminate according to any one of [1] to [17].

[19] 0.01 to 2.5 parts by weight of an isocyanate-based crosslinking agent (B) and 0.01 to 10 parts by weight of a silane compound (C) based on 100 parts by weight of (meth)acrylic resin (A), and A pressure-sensitive adhesive composition used for forming a pressure-sensitive adhesive layer laminated on a metal layer containing 0.2 to 8 parts by weight of an ionic compound (D).

M ⁺ X ^- (I)

(In formula (I), M ⁺ represents an inorganic cation, and X ^- represents a fluorine atom-containing anion.)

According to the present invention, it is possible to provide an optical laminate capable of suppressing corrosion of a metal layer, and a liquid crystal display device including the same.

1 is a schematic cross-sectional view showing an example of an optical laminate according to the present invention.
2 is a schematic cross-sectional view showing an example of a layer configuration of a polarizing plate.
3 is a schematic cross-sectional view showing another example of a layer configuration of a polarizing plate.
4 is a schematic cross-sectional view showing an example of the layer structure of the optical laminate.
5 is a schematic cross-sectional view showing another example of the layer structure of the optical laminate.
6 is a schematic cross-sectional view showing another example of the layer structure of the optical laminate.
7 is a schematic cross-sectional view showing another example of the layer structure of the optical laminate.

<Optical laminate>

1 is a schematic cross-sectional view showing an example of an optical laminate according to the present invention. As shown in FIG. 1 , the optical laminate according to the present invention includes the optical film 10, the pressure-sensitive adhesive layer 20, and the metal layer 30 in this order, even if the substrate 40 is further included. good night. This optical layered body is an optical film with an adhesive layer comprising an optical film 10 on a metal layer 30 formed on a substrate 40 and an adhesive layer 20 laminated on at least one surface thereof. (1) may be bonded through the pressure-sensitive adhesive layer 20.

The pressure-sensitive adhesive layer 20 is usually laminated directly on the surface of the optical film 10 . Moreover, normally, the optical film 1 with an adhesive layer is laminated|stacked on the metal layer 30 so that the adhesive layer 20 may directly contact the metal layer 30. According to the present invention, in such an optical laminate, corrosion of the metal layer 30 can be effectively suppressed. Hereinafter, the property capable of suppressing corrosion of the metal layer 30 is also referred to as “metal corrosion resistance”.

The optical film 10 may be an optical film having a single layer structure or an optical film having a multilayer structure. The pressure-sensitive adhesive layer 20 is composed of a pressure-sensitive adhesive composition containing a (meth)acrylic resin (A), an isocyanate-based crosslinking agent (B), a silane compound (C), and an ionic compound (D). This adhesive composition may also contain another component. In this specification, "(meth)acryl" means at least one selected from the group consisting of acryl and methacryl. The same applies to "(meth)acrylate" or "(meth)acryloyl".

[1] Optical film

The optical film 10 included in the optical layered body according to the present invention is an optical member constituting the optical film 1 with a pressure-sensitive adhesive layer, and various optical films (optical properties) that can be incorporated in image display devices such as liquid crystal display devices. A film having a) may be. The optical film 10 may be an optical film having a single layer structure or an optical film having a multilayer structure. Specific examples of the optical film having a single-layer structure include optical functional films such as retardation films, brightness enhancement films, anti-glare films, antireflection films, diffusion films, condensing films, and the like, in addition to polarizers. Specific examples of the optical film having a multilayer structure include a polarizing plate and a retardation plate. In this specification, a polarizing plate means what a resin film or resin layer was laminated|stacked on at least one surface of a polarizer. A retardation plate means what a resin film or resin layer laminated|stacked on at least one surface of retardation film. The optical film 10 is preferably a polarizing plate, polarizer, retardation plate or retardation film, more preferably a polarizing plate or polarizer.

[1-1] Polarizer

2 and 3 are schematic cross-sectional views showing an example of a layer configuration of a polarizing plate. The polarizing plate 10a shown in FIG. 2 is a single-side protective polarizing plate in which the first resin film 3 is laminated and bonded on one side of the polarizer 2, and the polarizing plate 10b shown in FIG. 3 is a polarizer 2 ) is a double-sided protective polarizing plate in which the second resin film 4 is further laminated and bonded on the other side of the polarizing plate. The 1st, 2nd resin films 3 and 4 can be bonded to the polarizer 2 via the adhesive layer or adhesive layer not shown. Polarizing plates 10a and 10b may contain films and layers other than the first and second resin films 3 and 4 .

Examples of the layer structure of the optical laminate when the polarizing plates 10a and 10b shown in FIGS. 2 and 3 are used as the optical film 10 are shown in FIGS. 4 and 5 , respectively. The optical layered body 5 shown in FIG. 4 is an example in which the polarizing plate 10a shown in FIG. 2 is used as the optical film 10, and the optical layered body 6 shown in FIG. 5 is shown in FIG. 3 This is an example of using the polarizing plate 10b as the optical film 10.

The polarizer 2 is a film having a property of absorbing linearly polarized light having a oscillation plane parallel to the absorption axis and transmitting linearly polarized light having a oscillation plane orthogonal to the absorption axis (parallel to the transmission axis). A film in which a dichroic dye is adsorbed and oriented on a vinyl alcohol-based resin film can be used. As the dichroic dye, iodine or a dichroic organic dye is used.

A polyvinyl alcohol-type resin can be obtained by saponifying a polyvinyl acetate-type resin. Examples of the polyvinyl acetate-based resin include polyvinyl acetate which is a homopolymer of vinyl acetate, as well as copolymers of vinyl acetate and monomers copolymerizable with vinyl acetate and vinyl acetate. Examples of monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having an ammonium group.

The degree of saponification of the polyvinyl alcohol-based resin is usually 85 to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The average polymerization degree of polyvinyl alcohol-type resin is 1000-10000 normally, Preferably it is 1500-5000. The average degree of polymerization of polyvinyl alcohol-based resin can be determined in accordance with JIS K 6726.

Usually, what formed a polyvinyl alcohol-type resin into a film is used as a raw film of the polarizer 2. Polyvinyl alcohol-type resin can be formed into a film by a well-known method. The thickness of the raw film is usually 1 to 150 μm, and considering ease of stretching and the like, it is preferably 10 μm or more.

The polarizer 2 is, for example, a step of uniaxially stretching the original film, a step of dyeing the film with a dichroic dye and adsorbing the dichroic dye, a step of treating the film with an aqueous solution of boric acid, and washing the film with water The process of doing is performed, and finally dried and manufactured. The thickness of the polarizer 2 is usually 1 to 30 μm, and from the viewpoint of thinning the optical film 1 with the pressure-sensitive adhesive layer, it is preferably 20 μm or less, more preferably 15 μm or less, still more preferably 10 μm. below

The polarizer 2 formed by adsorbing and orienting a dichroic dye on a polyvinyl alcohol-based resin film is 1) using a single film of a polyvinyl alcohol-based resin film as a raw film, and uniaxial stretching treatment and dichroism for this film In addition to the method of dyeing the dye, 2) coating and drying a coating solution (such as an aqueous solution) containing polyvinyl alcohol-based resin on the base film to obtain a base film having a polyvinyl alcohol-based resin layer, and then applying this to the base film It can be obtained also by the method of carrying out uniaxial stretching as a whole, performing the dyeing process of the dichroic dye with respect to the polyvinyl alcohol-type resin layer after extending|stretching, and then peeling and removing the base film. As the base film, a film made of the same thermoplastic resin as the thermoplastic resin that can constitute the first and second resin films 3 and 4 described later can be used, and preferably polyesters such as polyethylene terephthalate. It is a film made of resin, polycarbonate-based resin, cellulose-based resin such as triacetyl cellulose, cyclic polyolefin-based resin such as norbornene-based resin, polystyrene-based resin, or the like. According to the method of 2) above, production of the thin film polarizer 2 becomes easy, and production of the polarizer 2 having a thickness of, for example, 7 μm or less also becomes easy.

The first and second resin films 3 and 4 are each independently made of a light-transmitting, preferably optically transparent, thermoplastic resin such as chain polyolefin resin (polyethylene resin, polypropylene resin, etc.), cyclic polyolefin polyolefin-based resins such as resins (norbornene-based resins, etc.); cellulosic resins (such as cellulose ester resins); polyester-based resins (such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate); polycarbonate-based resin; (meth)acrylic resin; polystyrene-based resin; polyether ether ketone-based resins; It may be a film made of a polysulfone-based resin, or a mixture or copolymer thereof. Among them, the first and second resin films 3 and 4 are resins selected from the group consisting of cyclic polyolefin-based resins, polycarbonate-based resins, cellulose-based resins, polyester-based resins, and (meth)acrylic-based resins, respectively. It is preferably composed of, and more preferably composed of a resin selected from the group consisting of cellulose-based resins and cyclic polyolefin-based resins.

Examples of the chain polyolefin-based resin include homopolymers of chain olefins such as polyethylene resins and polypropylene resins, as well as copolymers composed of two or more types of chain olefins.

The cyclic polyolefin-based resin is a general term for resins containing, as polymerized units, cyclic olefins such as norbornene, tetracyclododecene (another name: dimethanooctahydronaphthalene), or derivatives thereof. Specific examples of cyclic polyolefin-based resins include ring-opening (co)polymers of cyclic olefins and hydrogenated products thereof, addition polymers of cyclic olefins, copolymers of cyclic olefins with chain olefins such as ethylene and propylene, or aromatic compounds having a vinyl group; and modified (co)polymers obtained by modifying them with unsaturated carboxylic acids or derivatives thereof. Among them, a norbornene-based resin using a norbornene-based monomer such as norbornene or a polycyclic norbornene-based monomer as the cyclic olefin is preferably used.

The cellulose-based resin is preferably a cellulose ester-based resin, that is, a partial or complete esterified product of cellulose, and examples thereof include cellulose acetate esters, propionic acid esters, butyric acid esters, and mixed esters thereof. Among them, triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, cellulose acetate butylate and the like are preferably used.

The polyester-based resin is a resin other than the above-mentioned cellulose ester-based resin having an ester bond, and is generally composed of a polycondensate of a polyhydric carboxylic acid or a derivative thereof and a polyhydric alcohol. Specific examples of the polyester-based resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexane dimethyl terephthalate, and polycyclohexane. Contains dimethylnaphthalate.

Polycarbonate resin is a polyester formed from carbonic acid and glycol or bisphenol. Among them, an aromatic polycarbonate having diphenylalkane in its molecular chain is preferably used from the viewpoints of heat resistance, weather resistance and acid resistance. As polycarbonate, 2,2-bis (4-hydroxyphenyl) propane (alias bisphenol A), 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) cyclo Polycarbonates derived from bisphenols such as hexane, 1,1-bis(4-hydroxyphenyl)isobutane, and 1,1-bis(4-hydroxyphenyl)ethane are exemplified.

The (meth)acrylic resin that can constitute the first and second resin films 3 and 4 can be a polymer mainly composed of structural units derived from methacrylic acid ester (for example, containing 50% by weight or more of this). , It is preferable that it is a copolymer in which another copolymerization component is copolymerized. (Meth)acrylic-type resin may contain 2 or more types of structural units derived from methacrylic acid ester. As methacrylic acid ester, _C1 - _C4 alkyl ester of methacrylic acid, such as methyl methacrylate, ethyl methacrylate, and butyl methacrylate, is mentioned.

As a copolymerization component which can be copolymerized with methacrylic acid ester, acrylic acid ester is mentioned. The acrylic acid ester is preferably a C ₁ -C ₈ alkyl ester of acrylic acid such as methyl acrylate, ethyl acrylate, butyl acrylate, or 2-ethylhexyl acrylate. Specific examples of other copolymerization components include unsaturated acids such as (meth)acrylic acid; Aromatic vinyl compounds, such as styrene, halogenated styrene, (alpha)-methylstyrene, and vinyltoluene; vinyl cyan compounds such as (meth)acrylonitrile; unsaturated acid anhydrides such as maleic anhydride and citraconic anhydride; and compounds other than acrylic acid esters having one polymerizable carbon-carbon double bond in the molecule, such as unsaturated imides such as phenylmaleimide and cyclohexylmaleimide. A compound having two or more polymerizable carbon-carbon double bonds in its molecule may be used as the copolymerization component. As for a copolymerization component, only 1 type may be used and 2 or more types may be used together.

The (meth)acrylic resin may have a ring structure in the polymer main chain from the viewpoint of improving the durability of the film. The ring structure is preferably a heterocyclic structure such as a cyclic acid anhydride structure, a cyclic imide structure, or a lactone ring structure. Specific examples of the cyclic acid anhydride structure include glutaric anhydride structure and succinic anhydride structure, examples of the cyclic imide structure include glutarimide structure and succinimide structure, and specific examples of the lactone ring structure , a butyrolactone ring structure, and a valerolactone ring structure, respectively.

The (meth)acrylic resin may contain acrylic rubber particles from the viewpoint of the film forming property of the film or the impact resistance of the film. The acrylic rubber particles are particles containing an acrylic acid ester-based elastomer as an essential component, and examples include single-layered particles consisting essentially of only the elastic polymer and multi-layered particles containing an elastic polymer as one layer. As an example of an elastic polymer, the crosslinked elastic copolymer which has alkyl acrylate as a main component and copolymerized the other vinyl monomer and crosslinkable monomer which can be copolymerized with this is mentioned. Examples of the alkyl acrylate serving as the main component of the elastic polymer include C ₁ -C ₈ alkyl esters of acrylic acid such as methyl acrylate, ethyl acrylate, butyl acrylate and 2-ethylhexyl acrylate. The number of carbon atoms in the alkyl group is preferably 4 or more.

Examples of other vinyl monomers copolymerizable with alkyl acrylate include compounds having one polymerizable carbon-carbon double bond in the molecule, more specifically, methacrylic acid esters such as methyl methacrylate, aromatics such as styrene, and vinyl cyan compounds such as vinyl compounds and (meth)acrylonitrile. Examples of the crosslinkable monomer include crosslinkable compounds having at least two polymerizable carbon-carbon double bonds in the molecule, more specifically, ethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, etc. alkenyl esters of (meth)acrylic acid such as (meth)acrylates and allyl (meth)acrylates of polyhydric alcohols, divinylbenzene, and the like.

The content of the acrylic rubber particles is preferably 5 parts by weight or more, more preferably 10 parts by weight or more with respect to 100 parts by weight of the (meth)acrylic resin. If the content of the acrylic rubber particles is too large, the surface hardness of the film may decrease, and also, when the film is subjected to surface treatment, the solvent resistance to organic solvents in the surface treatment agent may decrease. Therefore, the content of the acrylic rubber particles is usually 80 parts by weight or less, preferably 60 parts by weight or less, based on 100 parts by weight of the (meth)acrylic resin.

The first and second resin films 3 and 4 may contain additives common in the technical field of the present invention. Specific examples of additives include, for example, ultraviolet absorbers, infrared absorbers, organic dyes, pigments, inorganic dyes, antioxidants, antistatic agents, surfactants, lubricants, dispersants, heat stabilizers, and the like.

Examples of the ultraviolet absorber include salicylic acid ester compounds, benzophenone compounds, benzotriazole compounds, triazine compounds, cyano (meth)acrylate compounds, and nickel complex salts.

The first and second resin films 3 and 4 may each be an unstretched film or a uniaxially or biaxially stretched film. Biaxial stretching may be simultaneous biaxial stretching in which the film is simultaneously stretched in two stretching directions, or sequential biaxial stretching in which the film is stretched in a predetermined direction and then in another direction. The first resin film 3 and/or the second resin film 4 may be a protective film that serves to protect the polarizer 2, or may be a protective film having an optical function such as a retardation film described later. there is. The retardation film is an optical film exhibiting optical anisotropy. For example, by stretching the film made of the thermoplastic resin (eg, uniaxial stretching or biaxial stretching) or forming a liquid crystal layer or the like on the thermoplastic resin film, a retardation film having an arbitrary retardation value can be obtained.

The first resin film 3 and the second resin film 4 may be films composed of the same thermoplastic resin or may be films composed of mutually different thermoplastic resins. The first resin film 3 and the second resin film 4 may be the same or different in thickness, presence/absence or type of additives, retardation characteristics, and the like.

The first resin film 3 and/or the second resin film 4 is a hard coat layer, an antiglare layer, an antireflection layer, a light diffusion layer, an antistatic layer, and an antifouling layer on the outer surface (the surface on the opposite side to the polarizer 2). , a surface treatment layer (coating layer) such as a conductive layer may be provided.

The thickness of the first resin film 3 and the second resin film 4 is usually 1 to 150 μm, preferably 5 to 100 μm, more preferably 5 to 60 μm, respectively. The said thickness may be 50 micrometers or less, Furthermore, 30 micrometers or less may be sufficient. Reducing the thickness of the first and second resin films 3 and 4 includes thinning the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate, and further including the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate. It becomes advantageous for thinning of the liquid crystal display device to do.

In particular, in small and medium-sized polarizers such as smartphones and tablet terminals, thin ones with a thickness of 30 μm or less are often used as the first resin film 3 and / or the second resin film 4 because of the demand for thinning. , Such a polarizing plate is weak in the force to suppress the shrinking force of the polarizer 2, and thus the durability is likely to be insufficient. ADVANTAGE OF THE INVENTION According to this invention, even when using such a polarizing plate as an optical film 10, the optical film 1 with an adhesive layer and optical laminated body which have favorable durability can be provided. The durability of the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate refers to the pressure-sensitive adhesive layer 20 and the optical member adjacent thereto in a high-temperature environment, a high-temperature, high-humidity environment, or an environment in which high and low temperatures are repeated. It refers to a property that can suppress problems such as lifting or peeling at the interface of the adhesive layer 20 and foaming.

In addition, from the viewpoint of thinning the polarizing plate, a configuration in which a resin film is disposed only on one side of the polarizer 2 is advantageous, as in the polarizing plate 10a shown in FIG. 2 . In this case, the adhesive layer 20 is bonded directly to the other surface of the polarizer 2 normally, and becomes the optical film 1 with an adhesive layer (refer FIG. 4). In the case of a polarizing plate having such a configuration, the problem of deteriorating the optical performance of the polarizing plate in a high-temperature, high-humidity environment due to the ionic compound contained in the pressure-sensitive adhesive layer 20 becomes particularly significant. According to the present invention, even when such a polarizing plate is used as the optical film 10, the optical film 1 with a pressure-sensitive adhesive layer and the optical laminate having good optical durability (property capable of suppressing deterioration of optical properties) can be provided. there is.

The 1st, 2nd resin films 3 and 4 can be bonded to the polarizer 2 via an adhesive bond layer or an adhesive layer. As the adhesive forming the adhesive layer, a water-based adhesive or an active energy ray-curable adhesive can be used.

Examples of the water-based adhesive include adhesives made of a polyvinyl alcohol-based resin aqueous solution, water-based two-component urethane emulsion adhesives, and the like. Among them, a water-based adhesive composed of a polyvinyl alcohol-based resin aqueous solution is preferably used. As the polyvinyl alcohol-based resin, in addition to a vinyl alcohol homopolymer obtained by saponifying polyvinyl acetate, which is a homopolymer of vinyl acetate, a polyvinyl alcohol-based copolymer obtained by saponifying a copolymer of vinyl acetate and another monomer copolymerizable therewith Combinations or modified polyvinyl alcohol-based polymers obtained by partially modifying their hydroxyl groups can be used. The water-based adhesive may contain a crosslinking agent such as an aldehyde compound, an epoxy compound, a melamine-based compound, a methylol compound, an isocyanate compound, an amine compound, or a polyvalent metal salt.

In the case of using a water-based adhesive, after bonding the polarizer 2 and the first and second resin films 3 and 4, it is preferable to perform a drying process in order to remove water contained in the water-based adhesive. You may provide the curing process of curing at the temperature of about 20-45 degreeC after a drying process, for example.

The active energy ray-curable adhesive refers to an adhesive that is cured by irradiating active energy rays such as ultraviolet rays or electron beams, and includes, for example, a curable composition containing a polymerizable compound and a photopolymerization initiator, a curable composition containing a photoreactive resin, and a binder resin. and a curable composition containing a photoreactive crosslinking agent. Preferably it is an ultraviolet curable adhesive. Examples of the polymerizable compound include photopolymerizable monomers such as photocurable epoxy monomers, photocurable (meth)acrylic monomers, and photocurable urethane monomers, and oligomers derived from photopolymerizable monomers. Examples of the photopolymerization initiator include substances that generate active species such as neutral radicals, anion radicals, and cation radicals when irradiated with active energy rays. As an active energy ray-curable adhesive containing a polymerizable compound and a photopolymerization initiator, a curable composition containing a photocurable epoxy monomer and a photocationic polymerization initiator or a curable composition containing a photocurable (meth)acrylic monomer and a photoradical polymerization initiator or a mixture of these curable compositions can be preferably used.

When using an active energy ray-curable adhesive, after bonding the polarizer 2 and the 1st, 2nd resin films 3 and 4, a drying process is performed as needed, and active energy is continued by irradiating an active energy ray. A curing step of curing the precurable adhesive is performed. The light source of the active energy ray is not particularly limited, but an ultraviolet ray having a luminous distribution at a wavelength of 400 nm or less is preferable, and specifically, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra-high pressure mercury lamp, a chemical lamp, a black light lamp, a microwave excitation A mercury vapor lamp, a metal halide lamp, or the like can be used.

In bonding the polarizer 2 and the 1st and 2nd resin films 3 and 4, surface activation treatment, such as a saponification process, a corona treatment, and a plasma process, can be performed on the bonding surface of at least any one of these. In the case where a resin film is bonded to both surfaces of the polarizer 2, the same type of adhesive or a different type of adhesive may be sufficient as the adhesive for bonding these resin films together.

The polarizing plates 10a and 10b may further include other films or layers. Specific examples thereof include a retardation film described later, a brightness enhancing film, an antiglare film, an antireflection film, a diffusion film, a condensing film, a pressure-sensitive adhesive layer other than the pressure-sensitive adhesive layer 20, a coating layer, and a protection film. The protection film is a film used for the purpose of protecting the surface of an optical film 10 such as a polarizing plate from scratches or stains, and is peeled off after bonding the optical film 1 with an adhesive layer onto, for example, the metal layer 30. It is customary to become

A protection film is normally comprised from a base film and the adhesive layer laminated|stacked on it. The base film may be a thermoplastic resin, for example, a polyolefin-based resin such as a polyethylene-based resin or a polypropylene-based resin; polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate; polycarbonate-based resin; It can be constituted with (meth)acrylic resin or the like.

[1-2] phase plate

As described above, the retardation film included in the retardation plate is an optical film exhibiting optical anisotropy, and can be used for the first and second resin films 3 and 4, in addition to the thermoplastic resins exemplified above, such as polyvinyl Alcohol-based resin, polyarylate-based resin, polyimide-based resin, polyethersulfone-based resin, polyvinylidene fluoride/polymethyl methacrylate-based resin, liquid crystal polyester-based resin, ethylene-vinyl acetate copolymer saponified product, poly It may be a stretched film obtained by stretching a resin film made of a vinyl chloride-based resin or the like by about 1.01 to 6 times. Among them, a stretched film obtained by uniaxially stretching or biaxially stretching a polycarbonate-based resin film, a cyclic olefin-based resin film, a (meth)acrylic-based resin film, or a cellulose-based resin film is preferable. In addition, in this specification, a zero retardation film is also included in retardation film (however, it can also be used as a protective film). In addition, films called uniaxial retardation film, wide viewing angle retardation film, low photoelasticity retardation film, etc. are also applicable as the retardation film.

The zero retardation film refers to a film in which both the in-plane retardation value (R _e ) and the thickness direction retardation value (R _th ) are -15 to 15 nm. This retardation film is suitably used for an IPS mode liquid crystal display device. The in-plane retardation value (R _e ) and the thickness direction retardation value (R _th ) are preferably -10 to 10 nm, and more preferably -5 to 5 nm. The in-plane retardation value (R _e ) and thickness direction retardation value (R _th ) here are values at a wavelength of 590 nm.

The in-plane retardation value (R _e ) and the thickness direction retardation value (R _th ) are each defined by the following formula.

R _e =(n _x -n _y )×d

R _th =[(n _x +n _y )/2-n _z ]×d

In the formula, n _x is the refractive index in the slow axis direction (x-axis direction) within the film plane, n _y is the refractive index in the fast axis direction (y-axis direction orthogonal to the x-axis within the plane) within the film plane, and n _z is It is the refractive index in the film thickness direction (the z-axis direction perpendicular to the film plane), and d is the thickness of the film.

As the zero retardation film, for example, a resin film made of polyolefin resins such as cellulose resins, chain polyolefin resins and cyclic polyolefin resins, polyethylene terephthalate resins, or (meth)acrylic resins can be used. In particular, since control of the retardation value is easy and acquisition is also easy, a cellulose-based resin, a polyolefin-based resin, or a (meth)acrylic-based resin is preferably used.

In addition, a film in which optical anisotropy is expressed by application/orientation of a liquid crystalline compound or a film in which optical anisotropy is expressed by application of an inorganic layered compound can also be used as a retardation film. Such a retardation film includes what is called a temperature compensation type retardation film, a film in which rod-shaped liquid crystals are obliquely aligned and sold under the trade name of "NH film" from JX Nikko Nisseki Energy Co., Ltd., Fujifilm Co., Ltd. A film in which disk-shaped liquid crystals are tilt-oriented, sold under the trade name of "WV film" from Sumitomo Chemical Co., Ltd., a completely biaxially oriented film sold under the trade name of "VAC film" from Sumitomo Chemical Co., Ltd., similarly to Sumitomo Chemical ( Note), there are biaxially oriented films sold under the trade name of "new VAC film".

The resin film laminated on at least one surface of the retardation film may be, for example, the protective film described above.

[2] Adhesive layer

The pressure-sensitive adhesive layer 20 disposed between the optical film 10 and the metal layer 30 contains a (meth)acrylic resin (A), an isocyanate-based crosslinking agent (B), a silane compound (C), and an ionic compound (D). It is composed of an adhesive composition containing In this adhesive composition, the ionic compound (D) is an ionic compound represented by the following formula (I).

M ⁺ X ^- (I)

In formula (I), M ⁺ represents an inorganic cation, and X ⁻ represents a fluorine atom-containing anion.

The above pressure-sensitive adhesive composition contains 0.01 to 2.5 parts by weight of an isocyanate-based crosslinking agent (B), 0.01 to 10 parts by weight of a silane compound (C) and an ionic compound (D ) is contained in an amount of 0.2 to 8 parts by weight.

According to the pressure-sensitive adhesive layer 20 composed of the above pressure-sensitive adhesive composition, corrosion of the metal layer 30 can be suppressed in the optical laminate having a configuration including the pressure-sensitive adhesive layer 20 and the metal layer 30, and furthermore, the pressure-sensitive adhesive The durability of the optical film 1 with a layer and an optical laminated body can be improved. Further, according to the pressure-sensitive adhesive layer 20 composed of the above-described pressure-sensitive adhesive composition, the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate may have a structure in which the pressure-sensitive adhesive layer 20 is directly bonded to the polarizer 2. durability can be demonstrated.

The thickness of the pressure-sensitive adhesive layer 20 is usually 2 to 40 μm, and from the viewpoints of the durability of the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate, the reworkability of the optical film 1 with the pressure-sensitive adhesive layer, etc., it is preferable. is 5 to 30 μm, more preferably 10 to 25 μm. In addition, when the thickness of the pressure-sensitive adhesive layer 20 is 10 μm or more, the followability of the pressure-sensitive adhesive layer 20 to the dimensional change of the optical film 10 becomes good, and when the thickness is 25 μm or less, the reworkability becomes good.

It is preferable that the pressure-sensitive adhesive layer 20 exhibits a storage modulus of 0.1 to 5 MPa in a temperature range of 23 to 80°C. Thereby, durability of the optical film 1 with an adhesive layer and an optical laminated body can be improved more effectively. “It shows a storage modulus of 0.1 to 5 MPa in a temperature range of 23 to 80°C” means that the storage modulus is a value within the above range at any temperature in this range. Since the storage modulus usually decreases gradually with an increase in temperature, if both the storage modulus at 23 ° C. and 80 ° C. fall within the above range, it can be considered that the storage elastic modulus within the above range is exhibited at a temperature in this range. The storage elastic modulus of the pressure-sensitive adhesive layer 20 can be measured using a commercially available viscoelasticity measuring device, for example, "DYNAMIC ANALYZER RDA II", a viscoelasticity measuring device manufactured by REOMETRIC.

[2-1] (meth)acrylic resin (A)

The (meth)acrylic resin (A) is a polymer or copolymer containing (preferably 50% by weight or more) a structural unit derived from a (meth)acrylic monomer as a main component. The (meth)acrylic monomer includes, for example, a monomer having a (meth)acryloyl group, and preferably includes an alkyl (meth)acrylate. The alkyl group of the alkyl (meth)acrylate has preferably 1 to 14 carbon atoms, more preferably 1 to 12 carbon atoms, still more preferably 1 to 8 carbon atoms, and may be linear, branched or cyclic. As the alkyl (meth)acrylate, an alkyl (meth)acrylate having a substituent such as an alkyl acrylate having a substituent in which a substituent is introduced into an alkyl group described later may be used. Alkyl (meth)acrylate may use only 1 type, and may use 2 or more types together.

Specific examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n- and i-propyl (meth) acrylate, n-, i- and t-butyl (meth) acrylate rate, n- and i-pentyl acrylate, n- and i-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n- and i-heptyl (meth) acrylate, n- and i-octyl ( meth)acrylate, 2-ethylhexyl (meth)acrylate, n- and i-nonyl (meth)acrylate, n- and i-decyl (meth)acrylate, isoboronyl (meth)acrylate, n - and i-dodecyl (meth)acrylate, stearyl (meth)acrylate and the like.

The (meth)acrylic resin (A) is a structural unit derived from an alkyl acrylate (a1) having a homopolymer glass transition temperature (Tg) of less than 0°C, and derived from an alkyl acrylate (a2) having a homopolymer Tg of 0°C or higher. It is preferable to contain the structural unit of. This is advantageous when improving the metal corrosion resistance and durability of the optical film 1 with an adhesive layer and an optical laminated body. As the Tg of the homopolymer of alkyl acrylate, for example, a literature value such as POLYMER HANDBOOK (Wiley-Interscience) can be employed.

Specific examples of the alkyl acrylate (a1) include ethyl acrylate, n- and i-propyl acrylate, n- and i-butyl acrylate, n-pentyl acrylate, n- and i-hexyl acrylate, n- The carbon number of an alkyl group such as heptyl acrylate, n- and i-octyl acrylate, 2-ethylhexyl acrylate, n- and i-nonyl acrylate, n- and i-decyl acrylate, and n-dodecyl acrylate An alkyl acrylate of about 2 to 12 is included. As another specific example of the alkyl acrylate (a1), a substituent-containing alkyl acrylate in which a substituent is introduced into the alkyl group in an alkyl acrylate having about 2 to 12 carbon atoms in the alkyl group can also be mentioned. The substituent of the substituent-containing alkyl acrylate is a group that substitutes a hydrogen atom of an alkyl group, and specific examples thereof include a phenyl group, an alkoxy group, and a phenoxy group. Specific examples of the substituent-containing alkyl acrylate include 2-methoxyethyl acrylate, ethoxymethyl acrylate, phenoxyethyl acrylate, and phenoxydiethylene glycol acrylate. The alkyl group of the alkyl acrylate (a1) may have an alicyclic structure, but is preferably a linear or branched alkyl group.

Alkyl acrylate (a1) may use only 1 type, and may use 2 or more types together. Especially, it is preferable that alkyl acrylate (a1) contains 1 type(s) or 2 or more types chosen from ethyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate. It is preferable that the alkyl acrylate (a1) contains n-butyl acrylate from the viewpoints of the followability to the optical film 10 of the pressure-sensitive adhesive layer 20 of the optical film 1 with the pressure-sensitive adhesive layer and the reworkability. .

The alkyl acrylate (a2) is an alkyl acrylate other than the alkyl acrylate (a1). Specific examples of the alkyl acrylate (a2) include methyl acrylate, cyclohexyl acrylate, isoboronyl acrylate, stearyl acrylate, t-butyl acrylate and the like.

Alkyl acrylate (a2) may use only 1 type, and may use 2 or more types together. Among them, from the viewpoint of metal corrosion resistance and durability, the alkyl acrylate (a2) preferably contains methyl acrylate, cyclohexyl acrylate, isoboronyl acrylate, etc., and methyl acrylate is included. more preferable

Content of the structural unit derived from the alkyl acrylate (a2) in (meth)acrylic-type resin (A) is from a viewpoint of the metal corrosion resistance of the optical film 1 with an adhesive layer and an optical laminated body, and durability, (meth) Of 100 parts by weight of all the constituent units constituting the acrylic resin (A), it is preferably 10 parts by weight or more, more preferably 15 parts by weight or more, still more preferably 20 parts by weight or more, and particularly preferably 25 parts by weight or more. more than one part by weight. Further, from the viewpoint of the followability of the pressure-sensitive adhesive layer 20 to the optical film 10 and the reworkability, the content of the structural unit derived from the alkyl acrylate (a2) is preferably 70 parts by weight or less, more preferably 60 parts by weight or less. It is 50 parts by weight or less, more preferably 50 parts by weight or less.

The (meth)acrylic resin (A) may contain constituent units derived from monomers other than alkyl acrylates (a1) and (a2). (Meth)acrylic-type resin (A) may contain only 1 type of structural units derived from the said other monomer, or may contain 2 or more types. Specific examples of other monomers are shown below.

1) Monomers with polar functional groups.

Examples of the monomer having a polar functional group include (meth)acrylates having substituents such as heterocyclic groups such as hydroxyl groups, carboxyl groups, substituted or unsubstituted amino groups, and epoxy groups. Specifically, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-(2-hydroxyethoxy)ethyl (meth)acrylate, monomers having a hydroxy group such as 2-chloro-2-hydroxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, and diethylene glycol mono(meth)acrylate; Acryloylmorpholine, vinylcaprolactam, N-vinyl-2-pyrrolidone, vinylpyridine, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, 3,4-epoxycyclohexyl monomers having heterocyclic groups such as methyl (meth)acrylate, glycidyl (meth)acrylate, and 2,5-dihydrofuran; monomers having a substituted or unsubstituted amino group such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and dimethylaminopropyl (meth)acrylate; and monomers having carboxyl groups such as (meth)acrylic acid and carboxyethyl (meth)acrylate. Especially, the monomer which has a hydroxyl group is preferable, and the (meth)acrylate which has a hydroxyl group is more preferable from the point of reactivity of a (meth)acrylic-type resin (A) and a crosslinking agent.

In addition to the (meth)acrylate having a hydroxy group, it may contain a monomer having the above-described other polar functional groups, but from the viewpoint of preventing the exfoliation force enhancement of the separation film that can be laminated on the outer surface of the pressure-sensitive adhesive layer 20, an amino group It is preferable to substantially not contain a monomer having Further, from the viewpoint of enhancing the corrosion resistance to ITO, it is preferable to substantially not contain a monomer having a carboxyl group. Here, "not substantially included" means 0.1 part by weight or less based on 100 parts by weight of all structural units constituting the (meth)acrylic resin (A).

2) Acrylamide-based monomers.

For example, N-methylolacrylamide, N-(2-hydroxyethyl)acrylamide, N-(3-hydroxypropyl)acrylamide, N-(4-hydroxybutyl)acrylamide, N-(5- Hydroxypentyl)acrylamide, N-(6-hydroxyhexyl)acrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, N-isopropylacrylamide, N-(3-dimethylamino Propyl)acrylamide, N-(1,1-dimethyl-3-oxobutyl)acrylamide, N-[2-(2-oxo-1-imidazolidinyl)ethyl]acrylamide, 2-acryloylamino -2-methyl-1-propanesulfonic acid, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N-(1-methylethoxymethyl) Acrylamide, N-(1-methylpropoxymethyl)acrylamide, N-(2-methylpropoxymethyl)acrylamide [alias: N-(isobutoxymethyl)acrylamide], N-(butoxymethyl)acrylamide Amide, N-(1,1-dimethylethoxymethyl)acrylamide, N-(2-methoxyethyl)acrylamide, N-(2-ethoxyethyl)acrylamide, N-(2-propoxyethyl) Acrylamide, N-[2-(1-methylethoxy)ethyl]acrylamide, N-[2-(1-methylpropoxy)ethyl]acrylamide, N-[2-(2-methylpropoxy)ethyl ]acrylamide [alias: N-(2-isobutoxyethyl)acrylamide], N-(2-butoxyethyl)acrylamide, N-[2-(1,1-dimethylethoxy)ethyl]acrylamide, etc. . Among them, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N-(butoxymethyl)acrylamide, N-(2-methylpropanol) Poxymethyl)acrylamide is preferably used.

3) Methacrylates, i.e. methacrylic acid esters.

For example, linear alkyl esters of methacrylic acid such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, n-octyl methacrylate and lauryl methacrylate; branched alkyl esters of methacrylic acid such as isobutyl methacrylate, 2-ethylhexyl methacrylate and i-octyl methacrylate; Isobornyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, cyclododecyl methacrylate, methylcyclohexyl methacrylate, trimethylcyclohexyl methacrylate, t-butylcyclohexyl methacrylate, alicyclic alkyl esters of methacrylic acid such as cyclohexylphenyl methacrylate; alkoxyalkyl esters of methacrylic acid such as 2-methoxyethyl methacrylate and ethoxymethyl methacrylate; methacrylic acid aralkyl esters such as benzyl methacrylate; 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2-(2-hydroxyethoxy)ethyl methacrylate, 2-chloro-2-hydroxy alkyl esters of methacrylic acid having a hydroxyl group, such as propyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, and diethylene glycol monomethacrylate; alkyl esters of methacrylic acid having a substituted or unsubstituted amino group such as aminoethyl methacrylate, N,N-dimethylaminoethyl methacrylate, and dimethylaminopropyl methacrylate; 2-phenoxyethyl methacrylate, 2-(2-phenoxyethoxy)ethyl methacrylate, ethylene oxide-modified nonylphenol ester of (meth)acrylic acid, 2-(o-phenylphenoxy)ethyl methacrylate, etc. Esters of methacrylic acid having a phenoxyethyl group of

4) Methacrylamide-based monomers.

For example, a methacrylamide-based monomer corresponding to the acrylamide-based monomer described in 1) above.

5) Styrenic monomers.

eg styrene; Alkyl styrene, such as methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, and octyl styrene; Halogenated styrene, such as fluoro styrene, chloro styrene, bromo styrene, dibromo styrene, and iodo styrene; nitrostyrene; acetyl styrene; methoxy styrene; divinylbenzene, etc.

6) Vinylic monomers.

For example, fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, and vinyl laurate; vinyl halides such as vinyl chloride and vinyl bromide; vinylidene halides such as vinylidene chloride; nitrogen-containing aromatic vinyls such as vinylpyridine, vinylpyrrolidone, and vinylcarbazole; conjugated diene monomers such as butadiene, isoprene, and chloroprene; unsaturated nitriles such as acrylonitrile and methacrylonitrile;

7) A monomer having a plurality of (meth)acryloyl groups in the molecule.

For example, 1,4-butanedioldi(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, 1,9-nonanedioldi(meth)acrylate, ethylene glycol di(meth)acrylate, di monomers having two (meth)acryloyl groups in the molecule, such as ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate; monomers having three (meth)acryloyl groups in the molecule, such as trimethylolpropane tri(meth)acrylate; and the like.

As described above, (meth)acrylic resin (A) is added to structural units derived from alkyl (meth)acrylates from the viewpoints of the durability and metal corrosion resistance of the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate, and , It is preferable to include a structural unit derived from a monomer having a polar functional group. The monomer having a polar functional group is preferably a (meth)acrylate-based monomer having a polar functional group, and more preferably a monomer having a hydroxyl group. The content of the constituent unit derived from the monomer having a polar functional group is preferably 0.1 to 10 parts by weight, more preferably 0.25 to 5 parts by weight, based on 100 parts by weight of the total constituent units constituting the (meth)acrylic resin (A). It is a weight part, More preferably, it is 0.5-5 weight part.

In addition, from a viewpoint of the reworkability of the optical film 1 with an adhesive layer, (meth)acrylic-type resin (A) is derived from methacrylic monomers, such as a methacrylate (methacrylic acid ester) and a methacrylamide-type monomer. It is preferable that the content of the structural unit is small, and specifically, the content of the structural unit is, in 100 parts by weight of the precursor unit constituting the (meth)acrylic resin (A), preferably 10 parts by weight or less, More preferably, it is 5 parts by weight or less, and it is still more preferable that it does not contain the structural unit substantially (0.1 part by weight or less).

The (meth)acrylic resin (A) preferably has a single peak in the range of 10 million to 2.5 million weight average molecular weight (Mw) on the emission curve in gel permeation chromatography (GPC), and the range of Mw 10 million to 2.5 million It has a single peak in , and more preferably contains structural units derived from alkyl acrylates (a1) and (a2). The adhesive layer 20 which uses such (meth)acrylic-type resin (A) as a base polymer is advantageous when improving durability of the optical film 1 with an adhesive layer and an optical laminated body. When the number of peaks in the Mw range is 2 or more, sufficient durability tends not to be obtained.

In obtaining the number of peaks of the GPC emission curve in the range of 1,000 to 2,500,000 Mw, the emission curve is obtained according to the GPC measurement conditions described in the section of the embodiment. "Having a single peak" in the above range of the obtained emission curve means having only one maximum value in the range of 1,000 to 2,500,000 Mw. In this specification, in the GPC emission curve, an S/N ratio of 30 or more is defined as a peak.

The (meth)acrylic resin (A) preferably has a Mw in terms of standard polystyrene by GPC in the range of 500,000 to 2.5 million, and more preferably in the range of 600,000 to 2,000,000. If Mw is 500,000 or more, it is advantageous for the metal corrosion resistance of the optical film 1 with an adhesive layer and the optical laminate and improvement in durability, and the reworkability of the optical film 1 with an adhesive layer also tends to improve. In addition, when Mw is 2,500,000 or less, the followability of the pressure-sensitive adhesive layer 20 to the dimensional change of the optical film 10 becomes good. The molecular weight distribution expressed by the ratio Mw/Mn of the weight average molecular weight (Mw) and the number average molecular weight (Mn) is usually 2 to 10. Mw and Mn of the (meth)acrylic resin (A) are obtained according to the GPC measurement conditions described in the section of Examples.

When the (meth)acrylic resin (A) is dissolved in ethyl acetate to obtain a solution having a concentration of 20% by weight, the viscosity at 25°C is preferably 20 Pa·s or less, and more preferably 0.1 to 7 Pa·s. desirable. The viscosity of such a range is advantageous in the improvement of the durability of the optical film 1 with an adhesive layer and an optical laminated body, and the reworkability of the optical film 1 with an adhesive layer. The said viscosity can be measured with a Brookfield viscometer.

The (meth)acrylic resin (A) preferably has a glass transition temperature (Tg) of -60 to -10°C, more preferably -55 to -15°C, as measured by a differential scanning calorimeter (DSC). Tg in such a range is advantageous to the metal corrosion resistance of the optical film 1 with an adhesive layer and an optical laminated body, and improvement of durability.

The pressure-sensitive adhesive composition may contain two or more types of (meth)acrylic resin belonging to (meth)acrylic resin (A). Moreover, the adhesive composition may contain other (meth)acrylic-type resin different from (meth)acrylic-type resin (A). However, from the viewpoint of the metal corrosion resistance and durability of the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate, the content of the (meth)acrylic-based resin (A) is preferably 70 in the total of all (meth)acrylic-based resins. It is weight% or more, More preferably, it is 80 weight% or more, More preferably, it is 90 weight% or more, It is especially preferable that the adhesive composition contains only (meth)acrylic-type resin (A) as a base polymer.

The (meth)acrylic resin (A) and other (meth)acrylic resins that can be used together as needed can be prepared by known methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization. can In manufacture of (meth)acrylic-type resin, a polymerization initiator is normally used. The polymerization initiator is used in an amount of about 0.001 to 5 parts by weight based on 100 parts by weight in total of all the monomers used for production of the (meth)acrylic resin. Further, the (meth)acrylic resin may be produced by, for example, a method of advancing polymerization with active energy rays such as ultraviolet rays.

As a polymerization initiator, a thermal polymerization initiator, a photoinitiator, etc. are used. As a photoinitiator, 4-(2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone etc. are mentioned, for example. As a thermal polymerization initiator, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile) ), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl-2,2'- azo compounds such as azobis(2-methylpropionate) and 2,2'-azobis(2-hydroxymethylpropionitrile); Lauryl peroxide, t-butyl hydroperoxide, benzoyl peroxide, t-butyl peroxybenzoate, cumene hydroperoxide, diisopropylperoxydicarbonate, dipropylperoxydicarbonate, t-butylperoxyneodecanoate , t-butylperoxypivalate, organic peroxides such as (3,5,5-trimethylhexanoyl) peroxide; and inorganic peroxides such as potassium persulfate, ammonium persulfate, and hydrogen peroxide. In addition, a redox type initiator in which a peroxide and a reducing agent are used in combination or the like can also be used as the polymerization initiator.

As a method for producing the (meth)acrylic resin, a solution polymerization method is preferable among the methods shown above. One example of the solution polymerization method is to mix the monomers and organic solvents used, add a thermal polymerization initiator under a nitrogen atmosphere, and stir at about 40 to 90°C, preferably about 50 to 80°C for about 3 to 15 hours. . In order to control the reaction, monomers and thermal polymerization initiators may be continuously or intermittently added during polymerization, or may be added while dissolved in an organic solvent. Examples of organic solvents include aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propyl alcohol and isopropyl alcohol; Ketones, such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, etc. can be used.

[2-2] Isocyanate Crosslinking Agent (B)

The pressure-sensitive adhesive composition contains an isocyanate-based crosslinking agent (B). By using an isocyanate-type crosslinking agent (B) as a crosslinking agent, the metal corrosion resistance and durability of the optical film 1 with an adhesive layer and an optical laminated body can be improved. An isocyanate-type crosslinking agent (B) may be used individually by 1 type, or may use 2 or more types together.

The isocyanate-based crosslinking agent (B) is a compound having at least two isocyanato groups (-NCO) in the molecule, specifically, tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogen Addition xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, triphenylmethane triisocyanate and the like are exemplified. In addition, the isocyanate-based crosslinking agent (B) is a polyhydric alcohol compound adduct of these isocyanate compounds (for example, glycerol or trimethylolpropane adduct), isocyanurate compounds, biuret-type compounds, and also polyether polyols and polyesters Derivatives, such as an isocyanate compound of a urethane prepolymer type by addition reaction with polyol, acrylic polyol, polybutadiene polyol, polyisoprene polyol, etc., may be sufficient. Among the above, polyhydric alcohol compound adducts of tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate or these isocyanate compounds are particularly preferred, and from the viewpoint of the durability of the optical film 1 with a pressure-sensitive adhesive layer and the optical laminate, Xylylene diisocyanate or its polyhydric alcohol compound adduct is more preferable.

The content of the isocyanate-based crosslinking agent (B) is preferably 0.01 to 2.5 parts by weight, more preferably 0.1 to 2 parts by weight (e.g., 1 part by weight or less) based on 100 parts by weight of the (meth)acrylic resin (A). am. When content of an isocyanate-type crosslinking agent (B) exists in this range, it is advantageous in metal corrosion resistance of the optical film 1 with an adhesive layer and an optical laminated body, and durability coexistence.

The pressure-sensitive adhesive composition may use an isocyanate-based crosslinking agent (B) in combination with other crosslinking agents such as epoxy compounds, aziridine compounds, metal chelate compounds, peroxides, etc. From the viewpoint of metal corrosion resistance and durability of the optical layered body to be carried out, it is preferable that the pressure-sensitive adhesive composition contains only the isocyanate-based crosslinking agent (B) as a crosslinking agent, and in particular substantially contains no peroxide. "Not substantially included" here means that the content is 0.01 part by weight or less with respect to 100 parts by weight of the (meth)acrylic resin (A).

[2-3] Silane Compound (C)

The pressure-sensitive adhesive composition contains a silane compound (C). In this way, adhesion between the pressure-sensitive adhesive layer 20 and the metal layer 30 or the glass substrate can be improved. You may use 2 or more types of silane compounds (C).

Examples of the silane compound (C) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropyl. Triethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylethoxydimethylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethylan Toxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, etc. are mentioned.

The silane compound (C) may include a silicone oligomer type. The specific example of a silicone oligomer is as follows when it describes in the form of a combination of monomers.

3-mercaptopropyltrimethoxysilane-tetramethoxysilane oligomer;

3-mercaptopropyltrimethoxysilane-tetraethoxysilane oligomer,

3-mercaptopropyltriethoxysilane-tetramethoxysilane oligomer;

3-Mercaptopropyltriethoxysilane-tetraethoxysilane oligomer

mercaptopropyl group-containing oligomers such as the like;

mercaptomethyltrimethoxysilane-tetramethoxysilane oligomer;

mercaptomethyltrimethoxysilane-tetraethoxysilane oligomer;

mercaptomethyltriethoxysilane-tetramethoxysilane oligomer;

Mercaptomethyltriethoxysilane-tetraethoxysilane oligomer

mercaptomethyl group-containing oligomers such as the like;

3-glycidoxypropyltrimethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropyltrimethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropyltriethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropylmethyldimethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer;

3-glycidoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer;

3-glycidoxypropylmethyldiethoxysilane-tetraethoxysilane copolymer

3-glycidoxypropyl group-containing copolymers such as the like;

3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane oligomer;

3-methacryloyloxypropyltrimethoxysilane-tetraethoxysilane oligomer,

3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane oligomer,

3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane oligomer,

3-methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane oligomer;

3-methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane oligomer;

3-methacryloyloxypropylmethyldiethoxysilane-tetramethoxysilane oligomer,

3-methacryloyloxypropylmethyldiethoxysilane-tetraethoxysilane oligomer

methacryloyloxypropyl group-containing oligomers such as the like;

3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane oligomer;

3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane oligomer;

3-acryloyloxypropyltriethoxysilane-tetramethoxysilane oligomer;

3-acryloyloxypropyltriethoxysilane-tetraethoxysilane oligomer;

3-acryloyloxypropylmethyldimethoxysilane-tetramethoxysilane oligomer;

3-acryloyloxypropylmethyldimethoxysilane-tetraethoxysilane oligomer;

3-acryloyloxypropylmethyldiethoxysilane-tetramethoxysilane oligomer;

3-Acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane oligomer

acryloyloxypropyl group-containing oligomers such as the like;

vinyltrimethoxysilane-tetramethoxysilane oligomer,

vinyltrimethoxysilane-tetraethoxysilane oligomer,

vinyltriethoxysilane-tetramethoxysilane oligomer,

vinyltriethoxysilane-tetraethoxysilane oligomer,

vinylmethyldimethoxysilane-tetramethoxysilane oligomer,

vinylmethyldimethoxysilane-tetraethoxysilane oligomer,

vinylmethyldiethoxysilane-tetramethoxysilane oligomer,

Vinylmethyldiethoxysilane-tetraethoxysilane oligomer

vinyl group-containing oligomers such as the like;

3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer;

3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer;

3-aminopropyltriethoxysilane-tetramethoxysilane copolymer;

3-aminopropyltriethoxysilane-tetraethoxysilane copolymer;

3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer;

3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer;

3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer;

3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer

amino group-containing copolymers such as the like;

The content of the silane compound (C) in the pressure-sensitive adhesive composition is usually 0.01 to 10 parts by weight, preferably 0.03 to 5 parts by weight, more preferably 0.03 to 5 parts by weight, based on 100 parts by weight of the (meth)acrylic resin (A). It is 0.05 to 2 parts by weight, more preferably 0.1 to 1 part by weight. When the content of the silane compound (C) is 0.01 part by weight or more, the effect of improving the adhesion between the pressure-sensitive adhesive layer 20 and the metal layer 30 or the glass substrate is easily obtained. Moreover, when the content is 10 parts by weight or less, the bleed-out of the silane compound (C) from the pressure-sensitive adhesive layer 20 can be suppressed.

[2-4] ionic compound (D)

The pressure-sensitive adhesive composition contains an ionic compound (D). The ionic compound (D) is an ionic compound represented by the following formula (I). By using the ionic compound (D), not only good antistatic performance can be imparted to the pressure-sensitive adhesive layer 20, but also excellent metal corrosion resistance and optical durability can be imparted. The pressure-sensitive adhesive composition may contain one type or two or more types of ionic compounds (D).

M ⁺ X ^- (I)

(In formula (I), M ⁺ represents an inorganic cation, and X ^- represents a fluorine atom-containing anion.)

In the formula (I), M ⁺ represents an inorganic cation. Specific examples of inorganic cations include alkali metal ions such as lithium cation [Li ⁺ ], sodium cation [Na ⁺ ], potassium cation [K ⁺ ], and cesium cation [Cs ⁺ ]; and alkaline earth metal ions such as beryllium cation [Be ²⁺ ], magnesium cation [Mg ²⁺ ], and calcium cation [Ca ²⁺ ]. Especially, from the viewpoint of the metal corrosion resistance of the optical film 1 with an adhesive layer and the optical laminate, lithium cation [Li ⁺ ], potassium cation [K ⁺ ], or sodium cation [Na ⁺ ] is preferably used, and the pressure-sensitive adhesive From the viewpoint of the durability of the optical film 1 with a layer and the optical laminate, it is more preferable to use a potassium cation [K ⁺ ].

In the formula (I), X ⁻ represents a fluorine atom-containing anion. The anion containing a fluorine atom tends to easily give the ionic compound (D) excellent in antistatic performance. As the fluorine atom-containing anion, both inorganic anions and organic anions can be used. Specific examples of inorganic anions capable of constituting the ionic compound (D) include tetrafluoroborate anion [BF ₄ ^- ], hexafluorophosphate anion [PF ₆ ^- ], and hexafluoroarsenate anion [AsF _{6 ]} . ^- ], hexafluoroantimonate anion [SbF ₆ ^- ], hexafluoroniobate anion [NbF ₆ ^- ], hexafluorotantalate anion [TaF ₆ ^- ], bis(fluorosulfonyl)imide anion [(FSO ₂ ) ₂ N ^- ], (poly)hydrofluorofluoride anion [F(HF) _n ^- ] (n is about 1 to 3), and the like.

Specific examples of organic anions capable of constituting the ionic compound (D) include trifluoroacetate anion [CF ₃ COO ^- ], trifluoromethanesulfonate anion [CF ₃ SO ₃ ^- ], bis (trifluoro Methanesulfonyl)imide anion [(CF ₃ SO ₂ ) ₂ N ^- ], tris(trifluoromethanesulfonyl)methanide anion [(CF ₃ SO ₂ ) ₃ C ^- ], perfluorobutanesulfonate anion [C ₄ F ₉ SO ₃ ^- ], bis(pentafluoroethanesulfonyl)imide anion [(C ₂ F ₅ SO ₂ ) ₂ N ^- ], perfluorobutanoate anion [C ₃ F ₇ COO ^- ], (trifluoromethanesulfonyl)(trifluoromethanecarbonyl)imide anion [(CF ₃ SO ₂ )(CF ₃ CO)N ^- ], perfluoropropane-1,3-disulfonate anion [-O ₃ S(CF ₂ ) ₃ SO ₃ ^- ], tetraarylborate anion (such as tetrakis(pentafluorophenyl)borate anion, etc.), dicyanamid anion [(CN) ₂ N ^- ] and the following formula ( and imide anions represented by III).

The fluorine atom-containing anion is preferably a fluorine atom-containing anion represented by the following formula (II) from the viewpoint of antistatic performance, metal corrosion resistance and optical durability of the optical film with pressure-sensitive adhesive layer 1 and the optical laminate. Specific examples of the fluorine atom-containing anion represented by formula (II) include bis(fluorosulfonyl)imide anion, bis(trifluoromethanesulfonyl)imide anion, and tris(trifluoromethanesulfonyl)meta nide anion, bis(pentafluoroethanesulfonyl)imide anion, and the like. Among them, using an ionic compound (D) that is a bis(fluorosulfonyl)imide anion [FSI ^- ] or a bis(trifluoromethanesulfonyl)imide anion [TFSI ^- ] is an optical film with a pressure-sensitive adhesive layer. (1) and it is particularly advantageous for improving the antistatic performance, metal corrosion resistance and optical durability of the optical laminate. Y is preferably a nitrogen atom, m is preferably an integer of 0 to 4, more preferably an integer of 0 to 1, and particularly preferably 0.

[Y(SO ₂ C _m F _2m+1 ) _n ] ^- (II)

(In formula (II), Y represents a carbon atom or a nitrogen atom, n is 3 when Y is a carbon atom, n is 2 when Y is a nitrogen atom, and m represents an integer from 0 to 10.)

Preferable examples of the ionic compound (D) represented by the formula (I) include the following.

lithium bis(fluorosulfonyl)imide;

lithium bis(trifluoromethanesulfonyl)imide;

lithium bis(pentafluoroethanesulfonyl)imide;

lithium tris(trifluoromethanesulfonyl)methanide;

sodium bis(fluorosulfonyl)imide;

sodium bis(trifluoromethanesulfonyl)imide;

sodium bis(pentafluoroethanesulfonyl)imide;

sodium tris(trifluoromethanesulfonyl)methanide;

potassium bis(fluorosulfonyl)imide;

Potassium bis(trifluoromethanesulfonyl)imide

potassium bis(pentafluoroethanesulfonyl)imide;

Potassium tris(trifluoromethanesulfonyl)methanide.

The content of the ionic compound (D) in the pressure-sensitive adhesive composition is 0.2 to 8 parts by weight, preferably 0.2 to 7 parts by weight, more preferably based on 100 parts by weight of the (meth)acrylic resin (A). It is 0.3 to 5 parts by weight, particularly preferably 0.5 to 3 parts by weight. When the content of the ionic compound (D) is 0.2 parts by weight or more, it is advantageous to improve the antistatic performance, and when it is 8 parts by weight or less, it is advantageous to the metal corrosion resistance and durability of the optical film 1 with the pressure-sensitive adhesive layer and the optical laminate. .

Although the adhesive composition can use an antistatic agent other than that together with the ionic compound (D) represented by the said formula (I), metal corrosion resistance of the optical film 1 with an adhesive layer and an optical laminated body etc. From a viewpoint, it is preferable that an adhesive composition contains only the ionic compound (D) represented by the said formula (I) as an antistatic agent.

[2-5] Other ingredients

The pressure-sensitive adhesive composition may contain one or more additives such as a solvent, a crosslinking catalyst, an ultraviolet absorber, a weathering stabilizer, a tackifire, a plasticizer, a softener, a dye, a pigment, an inorganic filler, and light scattering fine particles. . In addition, it is also useful to mix an ultraviolet curable compound with the pressure-sensitive adhesive composition, form the pressure-sensitive adhesive layer, and then irradiate and cure the pressure-sensitive adhesive with ultraviolet rays to obtain a harder pressure-sensitive adhesive layer. Examples of the crosslinking catalyst include amine-based catalysts such as hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, polyamino resin and melamine resin. compounds can be mentioned.

The pressure-sensitive adhesive composition can contain a rust preventive that can enhance the metal corrosion resistance of the optical film with an adhesive layer 1 and the optical laminate. Examples of the rust inhibitor include triazole-based compounds such as benzotriazole-based compounds and other triazole-based compounds; thiazole-based compounds such as benzothiazole-based compounds and other thiazole-based compounds; imidazole-based compounds such as benzylimidazole-based compounds and other imidazole-based compounds; imidazoline-based compounds; quinoline-based compounds; pyridine-based compounds; pyrimidine-based compounds; indole-based compounds; amine-based compounds; urea-based compounds; sodium benzoate; benzyl mercapto compounds; di-sec-butylsulfide; and diphenylsulfoxide.

However, according to the present invention, since sufficient metal corrosion resistance can be obtained without containing the rust inhibitor, the content of the rust inhibitor is preferably as small as possible. In particular, the pressure-sensitive adhesive composition preferably does not substantially contain a triazole-based compound as a rust inhibitor, and more preferably does not substantially contain a rust preventive agent selected from the above compound groups. "Not substantially included" here means that the content is 0.01 part by weight or less with respect to 100 parts by weight of the (meth)acrylic resin (A).

[3] metal layer and substrate

The metal layer 30 is, for example, selected from the group consisting of aluminum, copper, silver, gold, iron, tin, zinc, nickel, molybdenum, chromium, tungsten, lead, and an alloy containing two or more metals selected from these It may be a layer containing one or more types, and from the viewpoint of conductivity, it is preferably a layer containing a metal element selected from the group consisting of aluminum, copper, silver and gold, and from the viewpoint of conductivity and cost, more preferably It is a layer containing aluminum element, More preferably, it is a layer containing aluminum element as a main component. To include as a main component means that the metal component constituting the metal layer 30 is 30% by weight or more of all metal components, and furthermore, 50% by weight or more.

The metal layer 30 may be, for example, a metal oxide layer such as ITO. However, since the optical film 1 with an adhesive layer according to the present invention has particularly good corrosion resistance to simple metals and alloys, the metal layer 30 is It is preferable to include a single metal composed of the above metal elements and/or an alloy containing two or more kinds of the above metal elements. However, the optical layered body may have a transparent electrode layer made of a metal oxide such as ITO together with such a metal layer 30 .

The shape (for example, thickness, etc.) and preparation method of the metal layer 30 are not particularly limited, and may be a metal foil, or may be formed by a vacuum deposition method, sputtering method, ion plating method, inkjet printing method, or gravure printing method. , Preferably it is a metal layer formed by the sputtering method, the inkjet printing method, and the gravure printing method, More preferably, it is a metal layer formed by sputtering. In the metal layer and metal foil formed by sputtering, the former tends to have poor corrosion resistance, but according to the optical laminate according to the present invention, it has good metal corrosion resistance also to the metal layer formed by sputtering. The thickness of the metal layer 30 is usually 3 μm or less, preferably 1 μm or less, and more preferably 0.8 μm or less. Moreover, the thickness of the metal layer 30 is 0.01 micrometer or more normally. In addition, when the metal layer 30 is a metal wiring layer, the line width of the metal wiring of the metal wiring layer is usually 10 μm or less, preferably 5 μm or less, and more preferably 3 μm or less. The line width of the metal wiring is usually 0.01 μm or more, preferably 0.1 μm or more, and more preferably 0.5 μm or more. Also for such a thin metal layer 30 or metal layer 30 composed of thin metal wires, the optical laminate according to the present invention exhibits good metal corrosion resistance. In particular, even when the metal wiring is, for example, 3 μm or less in thickness and 10 μm or less in thickness or 3 μm or less in thickness and 10 μm or less in line width and formed by a sputtering method, corrosion, particularly pitting, can be suppressed.

The metal layer 30 may be, for example, a metal wiring layer (ie, an electrode layer) of a touch input element of a touch input type liquid crystal display device. In this case, it is common that the metal layer 30 is patterned into a predetermined shape. When laminating the pressure-sensitive adhesive layer 20 on the patterned metal layer 30, the pressure-sensitive adhesive layer 20 may have a portion not in contact with the metal layer 30. The metal layer 30 may be a continuous film containing the above metal or alloy.

In addition, the metal layer 30 may have a single layer structure or a multilayer structure of two layers or three or more layers. Examples of the metal layer having a multilayer structure include a metal-containing layer (eg, metal mesh) having a three-layer structure represented by molybdenum/aluminum/molybdenum.

As shown in FIG. 1 , a metal layer 30 , for example, a metal wiring layer, is usually formed on a substrate 40 , and in this case, the optical laminate according to the present invention includes the substrate 40 . Formation of the metal layer 30 on the substrate 40 can be performed, for example, by sputtering. The substrate 40 may be a transparent substrate constituting a liquid crystal cell included in the touch input element. The substrate 40 is preferably a glass substrate. As a material of a glass substrate, soda lime glass, low alkali glass, alkali free glass etc. are mentioned, for example. The metal layer 30 may be formed on the entire surface of the substrate 40 or may be formed on a part thereof. When the metal layer 30 is formed on a part of the surface of the substrate 40, such as when the patterned metal layer 30 is formed on the substrate 40, a part of the pressure-sensitive adhesive layer 20 is made of, for example, glass. Although it comes into direct contact with the substrate 40, since the adhesive layer 20 in the optical laminate according to the present invention is also excellent in adhesion to glass, the optical laminate and the liquid crystal display device provided with the same are Durability in such a case is also excellent.

[4] Configuration and manufacturing method of optical laminate

In one embodiment, as shown in FIGS. 4 and 5 , the optical laminate according to the present invention includes an optical film 1 with a pressure-sensitive adhesive layer and a metal layer 30 laminated on the pressure-sensitive adhesive layer 20 side. include In the optical laminates 5 and 6 shown in FIGS. 4 and 5 , the optical film 1 with the pressure-sensitive adhesive layer is placed on the metal layer 30 so that the pressure-sensitive adhesive layer 20 directly contacts the metal layer 30. are layered. According to the present invention, corrosion of the metal layer 30 can be effectively suppressed even in an optical laminate having such a configuration in which the pressure-sensitive adhesive layer 20 directly contacts the metal layer 30 in this way.

6 is a schematic cross-sectional view showing another example of the layer structure of the optical laminate according to the present invention. In another embodiment, in the optical layered body according to the present invention, like the optical layered body 7 shown in FIG. and is laminated on the metal layer 30. The pressure-sensitive adhesive layer 20 is in direct contact with the resin layer 50 . Also in such an optical laminate 7, corrosion of the metal layer 30 can be effectively suppressed. The resin layer 50 disposed between the pressure-sensitive adhesive layer 20 and the metal layer 30 may be, for example, a cured material layer of a curable resin. As the curable resin capable of forming the resin layer 50, known ones can be used, and examples thereof include those described in Japanese Unexamined Patent Publication No. 2009-217037.

As described above, the metal layer 30 may be a metal wiring layer. An example in the case where the metal layer 30 is a metal wiring layer is shown in FIG. 7 . In the optical laminate shown in Fig. 7, the resin layer 50 may be omitted.

The optical laminate includes, for example, an optical film 10 on a metal layer 30 formed on a substrate 40, and an optical film with a pressure-sensitive adhesive layer 20 laminated on at least one surface thereof. It can be produced by bonding the film 1 through the pressure-sensitive adhesive layer 20 therebetween.

As mentioned above, the optical film 1 with an adhesive layer contains the optical film 10 and the adhesive layer 20 laminated|stacked on the at least one surface (FIG. 1). The pressure-sensitive adhesive layer 20 may be laminated on both sides of the optical film 10 . Usually, the pressure-sensitive adhesive layer 20 is directly laminated on the surface of the optical film 10 . When forming the pressure-sensitive adhesive layer 20 on the surface of the optical film 10, formation of a primer layer on the bonding surface of the optical film 10 and/or the bonding surface of the pressure-sensitive adhesive layer 20, surface activation treatment, such as plasma It is preferable to perform treatment, corona treatment, etc., and it is more preferable to perform corona treatment.

When the optical film 10 is a single-sided protective polarizing plate as shown in FIG. 2 , the pressure-sensitive adhesive layer 20 is usually formed on the polarizer surface, that is, on the opposite side of the first resin film 3 in the polarizer 2. It is preferably laminated directly onto the surface. When the optical film 10 is a double-sided protective polarizing plate as shown in FIG. 3, the pressure-sensitive adhesive layer 20 may be laminated on either outer surface of the first or second resin films 3, 4, or on both sides. may be laminated on the outer surface of

An antistatic layer may be separately formed between the optical film 10 and the pressure-sensitive adhesive layer 20, but since the pressure-sensitive adhesive layer 20 of the present invention can impart excellent antistatic properties with the pressure-sensitive adhesive layer alone, It is preferable not to have an antistatic layer between the optical film 10 and the adhesive layer 20 from the point of thinning or simplification of a laminate manufacturing process.

The optical film 1 with the pressure-sensitive adhesive layer may include a separate film (release film) laminated on the outer surface of the pressure-sensitive adhesive layer 20 . This separation film is usually peeled off at the time of use of the pressure-sensitive adhesive layer 20 (for example, at the time of lamination on the metal layer 30). The separate film may be, for example, a film made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarate, etc., on which a release treatment such as silicone treatment is performed on the surface on which the pressure-sensitive adhesive layer 20 is formed. there is.

The optical film 1 with a pressure-sensitive adhesive layer dissolves or disperses each component constituting the above-mentioned pressure-sensitive adhesive composition in a solvent to obtain a solvent-containing pressure-sensitive adhesive composition, and then applies and dries this on the surface of the optical film 10 to obtain an adhesive. It can be obtained by forming the layer (20). Further, the optical film 1 with the pressure-sensitive adhesive layer is formed by forming the pressure-sensitive adhesive layer 20 on the surface of the release treatment of the separate film in the same manner as above, and laminating (transferring) the pressure-sensitive adhesive layer 20 on the surface of the optical film 10. ) can also be obtained by

An optical laminated body can be obtained by bonding together the optical film 1 with an adhesive layer on the metal layer 30 (or the said resin layer) via the adhesive layer 20. After bonding the optical film 1 with the pressure-sensitive adhesive layer and the metal layer 30 to form an optical laminate, if there is any problem, the optical film 1 with the pressure-sensitive adhesive layer is peeled from the metal layer 30, and a separate What is called a rework operation which attaches the optical film 1 with an adhesive layer to the metal layer 30 again may be required. In the optical layered body according to the present invention, after the optical film 1 with the pressure-sensitive adhesive layer is peeled off from the metal layer 30, the surface of the metal layer 30 is less prone to blurring or adhesive residue, and has excellent reworkability. do. According to the optical laminate according to the present invention, good reworkability can be exhibited even when the surface to which the pressure-sensitive adhesive layer 20 is bonded is not the metal layer 30 but a glass substrate or an ITO layer.

<Liquid crystal display device>

A liquid crystal display device according to the present invention includes the optical laminate according to the present invention. The liquid crystal display device according to the present invention can suppress corrosion of the metal layer 30 and exhibits good durability.

The liquid crystal display device according to the present invention is preferably a touch input type liquid crystal display device having a touch panel function. A touch input type liquid crystal display device includes a touch input element including a liquid crystal cell and a backlight. The configuration of the touch panel may be any conventionally known method, such as an out-cell type, an on-cell type, or an in-cell type, and the operation method of the touch panel may be a resistive film type or a capacitive type (surface type capacitance type, projected type capacitance type) ) etc., any conventionally known method may be used. The optical layered body according to the present invention may be disposed on the viewing side of the touch input element (liquid crystal cell), may be disposed on the backlight side, or may be disposed on both sides. The driving method of the liquid crystal cell may be any conventionally known method such as a TN method, a VA method, an IPS method, a multi-domain method, or an OCB method. In the liquid crystal display device according to the present invention, the substrate 40 of the optical laminate may be a substrate (typically a glass substrate) included in the liquid crystal cell.

Example

Hereinafter, the present invention has been described in more detail by showing examples and comparative examples, but the present invention is not limited by these examples. Hereinafter, unless otherwise specified, parts and % showing usage amount and content are based on weight.

<Production Example 1: Production of (meth)acrylic resin (A-1) for pressure-sensitive adhesive layer>

A solution obtained by mixing monomers having the composition shown in Table 1 (the numerical values in Table 1 are parts by weight) with 81.8 parts of ethyl acetate was charged into a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer. After replacing the air in the reaction vessel with nitrogen gas, the internal temperature was set to 60°C. Thereafter, a solution obtained by dissolving 0.12 parts of azobisisobutyronitrile in 10 parts of ethyl acetate was added. After holding at the same temperature for 1 hour, ethyl acetate was continuously added into the reaction vessel at an addition rate of 17.3 parts/Hr to obtain a polymer concentration of approximately 35% while maintaining the internal temperature at 54 to 56°C. After maintaining the internal temperature at 54 to 56 ° C. until 12 hours elapsed from the start of addition of ethyl acetate, the concentration of the polymer was adjusted to 20% by adding ethyl acetate, (meth)acrylic resin (A-1) An ethyl acetate solution of was obtained. The weight average molecular weight (Mw) of (meth)acrylic resin (A-1) was 1,390,000, and the ratio Mw/Mn of the weight average molecular weight (Mw) and number average molecular weight (Mn) was 5.32. In the emission curve of gel permeation chromatography (GPC), a component with a Mw of 1.39 million showed a single peak, and no other peak was identified in the range of 10 million to 2.5 million Mw.

<Production Example 2: Production of (meth)acrylic resin (A-2) for pressure-sensitive adhesive layer>

An ethyl acetate solution of (meth)acrylic resin (A-2) was obtained (resin concentration: 20%) in the same manner as in Production Example 1 except that the composition of the monomers was set as shown in Table 1. The weight average molecular weight (Mw) of (meth)acrylic resin (A-2) was 1,410,000, and Mw/Mn was 4.71. In the emission curve of GPC, a component with Mw of 1.41 million showed a single peak, and no other peak was identified in the range of Mw of 10 million to 2.5 million.

In the above production example, the weight average molecular weight (Mw) and number average molecular weight (Mn) were measured using 4 "TSKgel XL" manufactured by Tosoh Co., Ltd. and "TSKgel XL" manufactured by Showa Denko Co., Ltd. as a column in a GPC apparatus. Shodex GPC KF-802", a total of 5 pieces were connected in series, and tetrahydrofuran was used as an eluent. Under the conditions, it was measured by standard polystyrene conversion. The conditions for obtaining the emission curve of GPC were also the same.

The glass transition temperature (Tg) was measured using a differential scanning calorimeter (DSC) "EXSTAR DSC6000" manufactured by SI Nanotechnology Co., Ltd., in a nitrogen atmosphere, in a measurement temperature range of -80 to 50 ° C., at a heating rate of 10 ° C./min. was measured under the conditions of

The composition of the monomers in each production example (the numbers in Table 1 are parts by weight) and the number of peaks in the Mw range of 10 million to 2.5 million on the GPC emission curve (indicated as “GPC peak number” in Table 1) are shown in Table 1. arranged in

Abbreviated names in the "monomer composition" column of Table 1 mean the following monomers.

BA: butyl acrylate (glass transition temperature of homopolymer: -54°C);

MA: methyl acrylate (glass transition temperature of homopolymer: 10°C),

HEA: 2-hydroxyethyl acrylate.

<Examples 1 to 3, Comparative Example 1>

(1) Preparation of pressure-sensitive adhesive composition

The isocyanate-based crosslinking agent (B) shown in Table 2, the silane compound (C), and An ionic compound (D) was mixed in an amount (parts by weight) shown in Table 2, and ethyl acetate was added so that the solid content concentration was 14% to obtain an adhesive composition. The compounding amount of each compounding component shown in Table 2 is the number of parts by weight as an active ingredient contained therein, when the product used contains a solvent or the like.

The details of each compounding component indicated by abbreviation in Table 2 are as follows.

(Isocyanate-based crosslinking agent)

B-1: An ethyl acetate solution of a trimethylolpropane adduct of xylylene diisocyanate (75% solid content concentration), trade name "Takenate D-110N" obtained from Mitsui Chemicals Co., Ltd.

(silane compound)

C-1: 3-glycidoxypropyl trimethoxysilane, trade name "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(ionic compound)

D-1: potassium bis(fluorosulfonyl)imide,

D-2: lithium bis(trifluoromethanesulfonyl)imide,

D-3: N-octyl-4-methylpyridinium hexafluorophosphate.

(2) Production of pressure-sensitive adhesive layer

Each pressure-sensitive adhesive composition prepared in (1) above was dried using an applicator on the release-treated surface of a separate film made of a polyethylene terephthalate film subjected to release treatment (trade name "PLR-382051" obtained from Lintec Co., Ltd.) It was applied to a thickness of 20 μm and dried at 100° C. for 1 minute to prepare a pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet).

(3) Production of optical film with pressure-sensitive adhesive layer (P-1)

A polyvinyl alcohol film having an average degree of polymerization of about 2400, a degree of saponification of 99.9 mol%, and a thickness of 60 μm [trade name “Kurare Vinylon VF-PE#6000” manufactured by Kuraray Co., Ltd.] was immersed in pure water at 37° C., It was immersed in an aqueous solution containing iodine and potassium iodide (iodine/potassium iodide/water (weight ratio) = 0.04/1.5/100) at 30°C. Then, it was immersed at 56.5 degreeC in the aqueous solution (potassium iodide / boric acid / water (weight ratio) = 12/3.6/100) containing potassium iodide and boric acid. After washing the film with pure water at 10°C, it was dried at 85°C to obtain a polarizer having a thickness of about 23 µm in which iodine was adsorbed and oriented in polyvinyl alcohol. Stretching was mainly performed in the steps of iodine dyeing and boric acid treatment, and the total stretching ratio was 5.3 times.

A transparent protective film (trade name "KC2UA" manufactured by Konica Minolta Opto Co., Ltd.) made of a triacetyl cellulose film having a thickness of 25 µm was bonded to one side of the obtained polarizer through an adhesive composed of an aqueous solution of polyvinyl alcohol-based resin. Next, on the surface opposite to the triacetyl cellulose film in the polarizer, a zero phase difference film made of a cyclic polyolefin-based resin having a thickness of 23 μm (trade name “ZEONOR” manufactured by Nippon Zeon Co., Ltd.) was applied to a polyvinyl alcohol-based A polarizing plate was produced by bonding through an adhesive composed of an aqueous solution of the resin. Subsequently, after corona discharge treatment for improving adhesion is performed on the surface opposite to the surface in contact with the polarizer in the zero phase difference film, the surface on the opposite side to the separate film of the pressure-sensitive adhesive layer produced in the above (2) (adhesive Layer surface) was bonded together with a laminator, and then it was cured for 7 days on conditions of a temperature of 23°C and a relative humidity of 65% to obtain an optical film with an adhesive layer (P-1).

(4) Production of optical film with pressure-sensitive adhesive layer (P-2)

A polyvinyl alcohol film having an average degree of polymerization of about 2400, a degree of saponification of 99.9 mol%, and a thickness of 30 μm [trade name “Kurarevinilon VF-PE#3000” manufactured by Kuraray Co., Ltd.] was immersed in pure water at 37° C., It was immersed in an aqueous solution containing iodine and potassium iodide (iodine/potassium iodide/water (weight ratio) = 0.04/1.5/100) at 30°C. Then, it was immersed at 56.5 degreeC in the aqueous solution (potassium iodide / boric acid / water (weight ratio) = 12/3.6/100) containing potassium iodide and boric acid. After washing the film with pure water at 10°C, it was dried at 85°C to obtain a polarizer having a thickness of about 12 µm in which iodine was adsorbed and oriented in polyvinyl alcohol. Stretching was mainly performed in the steps of iodine dyeing and boric acid treatment, and the total stretching ratio was 5.3 times.

On one side of the obtained polarizer, a transparent protective film made of a triacetyl cellulose film having a thickness of 25 μm (trade name “KC2UA” manufactured by Konica Minolta Opto Co., Ltd.) is bonded through an adhesive composed of an aqueous solution of polyvinyl alcohol-based resin to obtain a polarizing plate. was produced. Then, after bonding the surface (adhesive layer surface) on the opposite side to the separate film of the adhesive layer produced in said (2) to the surface opposite to the surface to which the protective film of the polarizer was bonded together with a laminator, the temperature was 23 ° C. , It cured on conditions of 65% of relative humidity for 7 days, and obtained the optical film with an adhesive layer (P-2).

(5) Evaluation of metal corrosion resistance of an optical film with an adhesive layer

The optical film with a pressure-sensitive adhesive layer (P-1) prepared in (3) above was cut into a test piece having a size of 20 mm × 50 mm, and adhered to the metal layer side of a glass substrate with a metal layer through the pressure-sensitive adhesive layer. As the glass substrate with a metal layer, a glass substrate (manufactured by Geomatech Co., Ltd.) in which a metal aluminum layer having a thickness of about 500 nm was laminated on the surface of an alkali-free glass by sputtering was used. After storing the obtained optical layered body in an oven at a temperature of 60° C. and a relative humidity of 90% for 500 hours, the state of the metal layer of the portion where the optical film with the pressure-sensitive adhesive layer was adhered was exposed to light from the back surface of the glass substrate, and a magnifying glass ( loupe), and evaluated for pitting (occurrence of a hole having a diameter of 0.1 mm or more and capable of transmitting light) according to the following criteria. The results are shown in Table 3.

4: The number of formulas generated on the surface of the metal layer is 2 or less,

3: The number of formulas generated on the surface of the metal layer is 3 to 5,

2: The number of formulas generated on the surface of the metal layer is 6 or more,

1: A large number of pitting is generated on the entire surface of the metal layer, and cloudiness is also generated.

(6) Evaluation of durability of optical film with pressure-sensitive adhesive layer

The optical film (P-1) with the pressure-sensitive adhesive layer prepared in (3) above is cut into a size of 200 mm × 150 mm so that the direction of the stretching axis of the polarizing plate becomes the long side, the separate film is peeled off, and the exposed pressure-sensitive adhesive layer surface is a glass substrate bonded to. The obtained test piece to which the glass substrate was adhered (optical film with an adhesive layer to which the glass substrate was adhered) was pressurized for 20 minutes at a temperature of 50°C and a pressure of 5 kg/cm 2 (490.3 kPa) in an autoclave. As the glass substrate, an alkali-free glass trade name "Eagle XG" manufactured by Corning Co., Ltd. was used. About the obtained optical laminated body, the following 3 types of durability tests were implemented.

[Durability test]

Heat resistance test maintained for 750 hours under dry conditions at a temperature of 85 ° C,

Moist heat resistance test maintained for 750 hours in an environment of a temperature of 60 ° C and a relative humidity of 90%,

Heat shock resistance (HS) test in which an operation of holding for 30 minutes under drying conditions at a temperature of 85° C. and subsequently holding for 30 minutes under drying conditions at a temperature of -40° C. is made one cycle, and this is repeated 400 cycles.

The optical laminate after each test was visually observed, the presence or absence of external appearance changes such as lifting, peeling, and foaming of the pressure-sensitive adhesive layer was visually observed, and durability was evaluated according to the following evaluation criteria. The results are shown in Table 3.

4: No change in appearance such as lifting, peeling, foaming, etc.

3: Almost no change in appearance such as lifting, peeling, foaming, etc.

2: Appearance changes such as lifting, peeling, and foaming are slightly conspicuous,

1: Significant changes in appearance such as lifting, peeling, and foaming were confirmed.

(7) Evaluation of reworkability of optical film with pressure-sensitive adhesive layer

The optical film with a pressure-sensitive adhesive layer (P-1) prepared in (3) above was cut into a test piece having a size of 25 mm x 150 mm. The separator was peeled off from the test piece, and the adhesive side was adhered to the glass substrate. The obtained test piece to which the glass substrate was adhered (optical film with an adhesive layer to which the glass substrate was adhered) was pressurized for 20 minutes at a temperature of 50°C and a pressure of 5 kg/cm 2 (490.3 kPa) in an autoclave. Next, it was stored in an oven at 50°C for 48 hours, and the optical film was peeled from the test piece together with the pressure-sensitive adhesive layer in a direction of 180° at a rate of 300 mm/min in an atmosphere of a temperature of 23°C and a relative humidity of 50%. The state of the surface of the glass substrate after peeling was observed and evaluated according to the following criteria. The results are shown in Table 3.

4: No cloudiness or the like was observed on the surface of the glass substrate.

3: Blurring etc. are hardly confirmed on the surface of the glass substrate,

2: Cloudiness etc. were confirmed on the surface of the glass substrate,

1: The residue of the adhesive layer was confirmed on the surface of the glass substrate.

(8) Evaluation of decolorization of optical film with pressure-sensitive adhesive layer

The optical film with a pressure-sensitive adhesive layer (P-2) prepared in (4) above was cut into a size of 30 mm x 30 mm, the separate film was peeled off, and the exposed pressure-sensitive adhesive layer surface was bonded to a glass substrate. As the glass substrate, an alkali-free glass trade name "Eagle XG" manufactured by Corning Co., Ltd. was used. For the obtained optical layered body, MD transmittance and TD transmittance were measured in the wavelength range of 380 to 780 nm using a spectrophotometer equipped with an integrating sphere (product name "V7100" manufactured by Nippon Bunko Co., Ltd.), and at each wavelength Calculate the single transmittance and polarization degree in JIS Z 8701: 1999 "Color display method - XYZ color system and X ₁₀ Y ₁₀ Z ₁₀ color system" 2-degree field of view (C light source), perform visibility correction, and A visibility-corrected single transmittance (Ty) and a visibility-corrected polarization degree (Py) were obtained. Further, the optical layered body was set in a spectrophotometer equipped with an integrating sphere so that the triacetyl cellulose film side of the polarizing plate was the detector side, and light was received from the glass substrate side.

Single transmittance and polarization degree are each defined by the following formula.

Single transmittance (λ)=0.5×(Tp(λ)+Tc(λ))

Degree of polarization (λ)=100×(Tp(λ)-Tc(λ))/(Tp(λ)+Tc(λ))

Tp(λ) is the transmittance (%) of the optical layered body measured in relation to linearly polarized light of incident wavelength λ (nm) and parallel Nicols, and Tc(λ) is linearly polarized light of incident wavelength λ (nm) It is the transmittance (%) of the optical layered body measured in relation to N and orthogonal Nicols.

Subsequently, after placing this optical laminate in a moist heat environment at a temperature of 80 ° C. and a relative humidity of 90% for 24 hours, and further placing it in an environment at a temperature of 23 ° C. and a relative humidity of 60% for 24 hours, the durability test was performed by the same method as before the durability test. The subsequent Ty and Py were obtained. Then, Py and Ty before the test were subtracted from Py and Ty after the test, respectively, to calculate the amount of change before and after the endurance test, and the amount of change in polarization degree (ΔPy) and the amount of change in single transmittance (ΔTy) were obtained. ΔPy is shown in Table 3.

<Production Example 1: Production of (meth)acrylic resin (A-1) for pressure-sensitive adhesive layer>

A solution obtained by mixing a monomer having a composition shown in Table 4 (the numerical values in Table 4 are parts by weight) with 81.8 parts of ethyl acetate was injected into a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer. After replacing the air in the reaction vessel with nitrogen gas, the internal temperature was set to 60°C. Then, a solution obtained by dissolving 0.12 parts of azobisisobutyronitrile in 10 parts of ethyl acetate was added. After holding at the same temperature for 1 hour, ethyl acetate was continuously added into the reaction vessel at an addition rate of 17.3 parts/Hr so that the concentration of the polymer was approximately 35%, while maintaining the internal temperature at 54 to 56°C. After maintaining the internal temperature at 54 to 56 ° C. until 12 hours elapsed from the start of addition of ethyl acetate, the concentration of the polymer was adjusted to 20% by adding ethyl acetate, (meth)acrylic resin (A-1) An ethyl acetate solution of was obtained. The weight average molecular weight (Mw) of (meth)acrylic resin (A-1) was 1,390,000, and the ratio Mw/Mn of the weight average molecular weight (Mw) and number average molecular weight (Mn) was 5.32. In the emission curve of gel permeation chromatography (GPC), a component with a Mw of 1.39 million showed a single peak, and no other peak was identified in the range of 10 million to 2.5 million Mw.

In the above production example, the weight average molecular weight (Mw) and number average molecular weight (Mn) were measured using 4 "TSKgel XL" manufactured by Tosoh Co., Ltd. and "TSKgel XL" manufactured by Showa Denko Co., Ltd. as a column in a GPC apparatus. Shodex GPC KF-802", a total of 5 pieces were connected in series, and tetrahydrofuran was used as an eluent. Under the conditions, it was measured by standard polystyrene conversion. The conditions for obtaining the emission curve of GPC were also the same.

The glass transition temperature (Tg) was measured using a differential scanning calorimeter (DSC) "EXSTAR DSC6000" manufactured by SI Nanotechnology Co., Ltd., in a nitrogen atmosphere, in a measurement temperature range of -80 to 50 ° C., at a heating rate of 10 ° C./min. was measured under the conditions of

The composition of the monomers in each production example (the numbers in Table 4 are parts by weight) and the number of peaks in the Mw range of 10 million to 2.5 million on the GPC emission curve (indicated as “GPC peak number” in Table 4) are listed in the table. summarized in 4.

Abbreviated names in the "monomer composition" column in Table 4 mean the following monomers.

BA: butyl acrylate (glass transition temperature of homopolymer: -54°C),

MA: methyl acrylate (glass transition temperature of homopolymer: 10°C),

HEA: 2-hydroxyethyl acrylate,

<Examples 4 to 5, Comparative Examples 2 to 3>

(1) Preparation of pressure-sensitive adhesive composition

Isocyanate-based crosslinking agent (B), silane compound (C) and ions shown in Table 5 with respect to 100 parts of solid content of the solution in the ethyl acetate solution (resin concentration: 20%) of the (meth)acrylic resin obtained in the above Production Example. The amount (parts by weight) shown in Table 5 was mixed with each of the sex compounds (D), and ethyl acetate was added so that the solid content concentration was 14% to obtain an adhesive composition. The compounding amount of each compounding component shown in Table 5 is the number of parts by weight as an active ingredient contained therein, when the product used contains a solvent or the like.

Details of each compounding component indicated by abbreviation in Table 5 are as follows.

(Isocyanate-based crosslinking agent)

B-1: An ethyl acetate solution of a trimethylolpropane adduct of xylylene diisocyanate (75% solid content concentration), trade name "Takenate D-110N" obtained from Mitsui Chemicals Co., Ltd.

(silane compound)

C-1: 3-glycidoxypropyl trimethoxysilane, trade name "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(ionic compound)

D-1: potassium bis(fluorosulfonyl)imide,

D-2: lithium bis(trifluoromethanesulfonyl)imide,

D-3: N-octyl-4-methylpyridinium hexafluorophosphate,

D-4: lithium iodide.

(2) Production of pressure-sensitive adhesive layer

Each pressure-sensitive adhesive composition prepared in (1) above was dried using an applicator on the release-treated surface of a separate film made of a polyethylene terephthalate film subjected to release treatment (trade name "PLR-382051" obtained from Lintec Co., Ltd.) It was applied to a thickness of 20 μm and dried at 100° C. for 1 minute to prepare a pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet).

(3) Production of optical film with pressure-sensitive adhesive layer (P-1)

A polyvinyl alcohol film having an average degree of polymerization of about 2400, a degree of saponification of 99.9 mol%, and a thickness of 60 μm [trade name “Kurare Vinylon VF-PE#6000” manufactured by Kuraray Co., Ltd.] was immersed in pure water at 37° C., It was immersed in an aqueous solution containing iodine and potassium iodide (iodine/potassium iodide/water (weight ratio) = 0.04/1.5/100) at 30°C. Then, it was immersed at 56.5 degreeC in the aqueous solution (potassium iodide / boric acid / water (weight ratio) = 12/3.6/100) containing potassium iodide and boric acid. After washing the film with pure water at 10°C, it was dried at 85°C to obtain a polarizer having a thickness of about 23 µm in which iodine was adsorbed and oriented in polyvinyl alcohol. Stretching was mainly performed in the steps of iodine dyeing and boric acid treatment, and the total stretching ratio was 5.3 times.

A transparent protective film (trade name "KC2UA" manufactured by Konica Minolta Opto Co., Ltd.) made of a triacetyl cellulose film having a thickness of 25 µm was bonded to one side of the obtained polarizer through an adhesive composed of an aqueous solution of polyvinyl alcohol-based resin. Next, a zero phase difference film made of a cyclic polyolefin-based resin having a thickness of 23 μm (trade name “ZEONOR” manufactured by Nippon Zeon Co., Ltd.) was applied to the surface opposite to the triacetyl cellulose film in the polarizer, and a polyvinyl alcohol-based resin A polarizing plate was manufactured by bonding through an adhesive consisting of an aqueous solution of Subsequently, after corona discharge treatment is performed on the surface opposite to the surface in contact with the polarizer in the zero phase difference film to improve adhesion, the surface of the pressure-sensitive adhesive layer produced in (2) above is opposite to the separate film (pressure-sensitive adhesive layer surface). After bonding) with a laminator, it cured for 7 days on the conditions of the temperature of 23 degreeC, and the relative humidity of 65%, and the optical film with an adhesive layer (P-1) was obtained.

(5) Evaluation of metal corrosion resistance of an optical film with an adhesive layer

<Comparative Example 2>

The optical film with a pressure-sensitive adhesive layer (P-1) prepared in (3) above was cut into a test piece having a size of 20 mm × 50 mm, and adhered to the metal layer side of a glass substrate with a metal layer through the pressure-sensitive adhesive layer. As the glass substrate with a metal layer, a glass substrate (manufactured by Geomatech Co., Ltd.) in which a metallic aluminum layer having a thickness of about 500 nm was laminated on the surface of an alkali-free glass by sputtering was used. After storing the obtained optical layered body in an oven at a temperature of 60° C. and a relative humidity of 90% for 500 hours, the state of the metal layer of the part where the optical film with the pressure-sensitive adhesive layer was adhered was exposed to light from the back surface of the glass substrate, and a magnifying glass was taken from the surface of the polarizing plate. Observation was made through observation, and pitting (occurrence of a hole having a diameter of 0.1 mm or more and capable of transmitting light) was evaluated according to the following criteria. The results are shown in Table 6.

<Examples 4 to 5, Comparative Example 3>

The optical film with a pressure-sensitive adhesive layer (P-1) prepared in (3) above was cut into a test piece having a size of 20 mm × 50 mm, and adhered to the metal layer side of a glass substrate with a metal layer through the pressure-sensitive adhesive layer. As the glass substrate with a metal layer, a glass substrate (manufactured by Geomatech Co., Ltd.) in which a silver alloy (alloy containing palladium and copper, APC) layer having a thickness of about 500 nm was laminated on the surface of an alkali-free glass by sputtering was used. used After storing the obtained optical layered body in an oven at a temperature of 60° C. and a relative humidity of 90% for 500 hours, the state of the metal layer of the part where the optical film with the pressure-sensitive adhesive layer was adhered was exposed to light from the back surface of the glass substrate, and a magnifying glass was taken from the surface of the polarizing plate. Observation was made through observation, and pitting (occurrence of a hole having a diameter of 0.1 mm or more and capable of transmitting light) was evaluated according to the following criteria. The results are shown in Table 6.

4: The number of formulas generated on the surface of the metal layer is 2 or less,

3: The number of formulas generated on the surface of the metal layer is 3 to 5,

2: The number of formulas generated on the surface of the metal layer is 6 or more,

1: A large number of pitting is generated on the entire surface of the metal layer, and cloudiness is also generated.

DESCRIPTION OF SYMBOLS 1: Optical film with adhesive layer, 2: Polarizer, 3: 1st resin film, 4: 2nd resin film, 5, 6, 7: Optical laminated body, 10: Optical film, 10a, 10b: Polarizing plate, 20: Adhesive layer, 30: metal layer, 40: substrate, 50: resin layer.

Claims (22)

An optical film, an adhesive layer, and a metal layer are included in this order,
The metal layer is a metal wiring layer of a touch input element, and is a group consisting of a simple metal composed of one metal element selected from the following metal element groups, and an alloy containing two or more types of metals selected from the following metal element groups. Including one or more selected from,
- Group of metal elements: copper, silver, iron, tin, zinc, nickel, molybdenum, chromium, tungsten, lead
The pressure-sensitive adhesive layer is composed of a pressure-sensitive adhesive composition containing a (meth)acrylic resin (A), an isocyanate-based crosslinking agent (B), a silane compound (C), and an ionic compound (D) represented by the following formula (I),
The optical film is a polarizer, a polarizing plate in which a resin film or a resin layer is laminated on at least one surface of the polarizer, a retardation film, or a retardation plate in which a resin film or a resin layer is laminated on at least one surface of the retardation film. Optical stack:
M ⁺ X ^- (I)
(In formula (I), M ⁺ represents an inorganic cation, and X ^- represents a fluorine atom-containing anion). delete The method of claim 1, wherein the pressure-sensitive adhesive composition contains 0.01 to 2.5 parts by weight of the isocyanate-based crosslinking agent (B) and 0.01 to 10 parts by weight of the silane compound (C), based on 100 parts by weight of the (meth)acrylic resin (A). An optical laminate containing 0.2 to 8 parts by weight of the ionic compound (D). The optical laminate according to claim 1, wherein the metal wiring layer has a line width of 10 µm or less. The optical laminate according to claim 1, wherein the inorganic cation is an alkali metal ion or an alkaline earth metal ion. The optical laminate according to claim 5, wherein the alkali metal ions are lithium cations, potassium cations, or sodium cations. The optical laminate according to claim 5, wherein the alkali metal ion is a potassium cation. The optical laminate according to claim 1, wherein the fluorine atom-containing anion is a fluorine atom-containing anion represented by the following formula (II):
[Y(SO ₂ C _m F _2m+1 ) _n ] ^- (II)
(In formula (II), Y represents a carbon atom or a nitrogen atom, n is 3 when Y is a carbon atom, n is 2 when Y is a nitrogen atom, and m represents an integer from 0 to 10). The optical laminate according to claim 1, wherein the fluorine atom-containing anion is a bis(fluorosulfonyl)imide anion or a bis(trifluoromethanesulfonyl)imide anion. The optical laminate according to claim 1, wherein the fluorine atom-containing anion is a bis(fluorosulfonyl)imide anion. The (meth)acrylic resin (A) according to claim 1, wherein the structural unit derived from an alkyl acrylate (a1) having a homopolymer glass transition temperature of less than 0°C and an alkyl acrylate having a homopolymer glass transition temperature of 0°C or higher An optical laminate containing structural units derived from rate (a2). The content of the structural unit derived from the alkyl acrylate (a2) of the (meth)acrylic resin (A) is 100 parts by weight of all the structural units constituting the (meth)acrylic resin (A) according to claim 11. , 10 parts by weight or more of the optical laminate. The optical laminate according to claim 11, wherein the alkyl acrylate (a2) includes methyl acrylate. The optical laminate according to claim 1, wherein the (meth)acrylic resin (A) contains a constituent unit derived from a monomer having a hydroxyl group. The (meth)acrylic resin (A) according to claim 1, wherein the content of structural units derived from a monomer having a carboxyl group is 0.1 part by weight based on 100 parts by weight of all structural units constituting the (meth)acrylic resin (A). The following optical laminates. The method of claim 1, wherein the pressure-sensitive adhesive composition comprises a triazole-based compound, a thiazole-based compound, an imidazole-based compound, an imidazoline-based compound, a quinoline-based compound, a pyridine-based compound, a pyrimidine-based compound, an indole-based compound, or an amine-based compound. , urea-based compound, sodium benzoate, benzyl mercapto-based compound, di-sec-butyl sulfide, and the content of the rust inhibitor selected from the group consisting of diphenyl sulfoxide relative to (meth) acrylic resin (A) 100 parts by weight An optical laminate of 0.01 parts by weight or less. The optical laminate according to claim 1, wherein the metal layer is a layer formed by sputtering. The optical laminate according to claim 1, wherein the metal layer has a thickness of 3 µm or less. A liquid crystal display device comprising the optical laminate according to claim 1. delete An optical film with a pressure-sensitive adhesive layer comprising an optical film and a pressure-sensitive adhesive layer laminated on at least one surface of the optical film, for bonding onto a metal layer through the pressure-sensitive adhesive layer,
The metal layer is a metal wiring layer of a touch input element, and is a group consisting of a simple metal composed of one metal element selected from the following metal element groups, and an alloy containing two or more types of metals selected from the following metal element groups. Including one or more selected from,
- Group of metal elements: copper, silver, iron, tin, zinc, nickel, molybdenum, chromium, tungsten, lead
The pressure-sensitive adhesive layer contains 0.01 to 2.5 parts by weight of an isocyanate-based crosslinking agent (B), 0.01 to 10 parts by weight of a silane compound (C), and the following formula (I), based on 100 parts by weight of (meth)acrylic resin (A). Formed from a pressure-sensitive adhesive composition containing 0.2 to 8 parts by weight of an ionic compound (D) represented by
The optical film is a polarizer, a polarizing plate in which a resin film or a resin layer is laminated on at least one surface of the polarizer, a retardation film, or a retardation plate in which a resin film or a resin layer is laminated on at least one surface of the retardation film. Optical film with adhesive layer:
M ⁺ X ^- (I)
(In formula (I), M ⁺ represents an inorganic cation, and X ^- represents a fluorine atom-containing anion). delete

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