JP6704280B2 - Optical laminate and liquid crystal display device - Google Patents

Description

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

An optical film represented by a polarizing plate obtained by laminating and laminating 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 attached to another member (for example, a liquid crystal cell or the like in a liquid crystal display device) via an adhesive layer [eg, JP 2010-229321 A (Patent Document 1). Reference 1)]. For this reason, as an optical film, an optical film with a pressure-sensitive adhesive layer having a pressure-sensitive adhesive layer provided on one surface in advance is known. Further, there is also known a pressure-sensitive adhesive layer containing an ionic compound in order to impart antistatic properties.

JP, 2010-229321, A

2. Description of the Related Art In recent years, liquid crystal display devices have been developed for mobile device applications having a touch panel function represented by smartphones, tablet terminals, and car navigation systems for vehicles. In such a touch input type liquid crystal display device, the optical film with a pressure-sensitive adhesive layer is arranged such that the pressure-sensitive adhesive layer is in direct contact with, for example, a resin layer or a metal layer composed of metal wiring. Sometimes. However, in a structure 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 under a high temperature and high humidity environment. Among the corrosions, pitting corrosion is a particular problem because the metal layer penetrates when the thickness of the metal layer is thin or when the metal layer is a metal wiring and the line width is narrow.

The present invention is an optical layered body in which an optical film with a pressure-sensitive adhesive layer is layered on a metal layer such as a metal wiring layer, and an optical layered body capable of suppressing corrosion of the metal layer, and the same. An object is to provide a liquid crystal display device.

The present invention provides the following optical laminate, a liquid crystal display device including the same, and an adhesive composition.

[1] An optical film, a pressure-sensitive 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),
The ionic compound (D) has the following formula (I):

(In the formula, A ⁺ represents an organic or inorganic cation.)
An optical laminate which is an ionic compound represented by.

[2] The metal layer is 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 [1], which comprises one or more kinds.

[3] The optical layered body according to [1] or [2], in which the metal layer contains an aluminum element.

[4] The optical layered body according to any one of [1] to [3], wherein the metal layer is a layer formed by sputtering.

[5] The optical layered body according to any one of [1] to [4], wherein the metal layer has a thickness of 3 μm or less.

[6] The optical layered body according to any one of [1] to [5], wherein A ^{+ in the} formula (I) is an organic cation.

[7] The optical layered body according to any one of [1] to [6], wherein A ^{+ in the} formula (I) is a nitrogen atom-containing organic cation.

[8] A ⁺ of the formula (I) is the following formula (II):

(In the formula, R ^{1 to} R ⁶ are each independently a hydrogen atom, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent which may have a substituent. A good alkynyl group, an aryl group which may have a substituent, a heterocyclic group which may have a substituent, a hydroxyl group, an ether group, a carboxyl group, a carbonyl group, or a halogen atom, and adjacent substituents The groups may form a ring.)
The optical laminate according to any one of [1] to [7], which is a pyridinium cation represented by.

[9] The (meth)acrylic resin (A) contains a structural unit derived from an alkyl(meth)acrylate in which an alkyl group has 1 to 14 carbon atoms, and a structural unit derived from a monomer having a hydroxyl group. The optical layered body according to any one of [1] to [8].

[10] The optical laminate according to any one of [1] to [9], in which the (meth)acrylic resin (A) does not substantially contain a structural unit derived from a monomer having a carboxyl group.

[11] The (meth)acrylic resin (A) has a structural unit derived from an alkyl acrylate (a1) in which the homopolymer has a glass transition temperature of lower than 0°C, and the homopolymer has a glass transition temperature of 0°C or higher. The optical laminate according to any one of [1] to [10], which contains a structural unit derived from an alkyl acrylate (a2).

[12] The content of the isocyanate crosslinking agent (B) in the pressure-sensitive adhesive composition is 0.08 to 2.5 parts by weight with respect to 100 parts by weight of the (meth)acrylic resin (A). The optical laminate according to any one of [1] to [11].

[13] The content of the ionic compound (D) in the pressure-sensitive adhesive composition is 0.2 to 8 parts by weight relative to 100 parts by weight of the (meth)acrylic resin (A), [1] ~ The optical laminate according to any one of [12].

[14] The pressure-sensitive adhesive composition is a triazole compound, a thiazole compound, an imidazole compound, an imidazoline compound, a quinoline compound, a pyridine compound, a pyrimidine compound, an indole compound, an amine compound, a urea compound, The rust preventive selected from the group consisting of sodium benzoate, benzyl mercapto compounds, di-sec-butyl sulfide, and diphenyl sulfoxide, which is substantially free of the rust preventive agent according to any one of [1] to [13]. Optical stack.

[15] A liquid crystal display device including the optical layered body according to any one of [1] to [14].
[16] contains a (meth)acrylic resin (A), an isocyanate crosslinking agent (B), a silane compound (C), and an ionic compound (D),
The ionic compound (D) has the following formula (I):

(In the formula, A ⁺ represents an organic or inorganic cation.)
Is an ionic compound represented by
A pressure-sensitive adhesive composition used for forming a pressure-sensitive adhesive layer laminated on a metal layer.

ADVANTAGE OF THE INVENTION According to this invention, the optical laminated body which can suppress the corrosion of a metal layer, and the liquid crystal display device containing this can be provided.

It is a schematic sectional drawing which shows an example of the optical laminated body which concerns on this invention. It is a schematic sectional drawing which shows an example of the layer structure of a polarizing plate. It is a schematic sectional drawing which shows another example of the layer structure of a polarizing plate. It is a schematic sectional drawing which shows an example of the laminated constitution of an optical laminated body. It is a schematic sectional drawing which shows another example of the layer structure of an optical laminated body. It is a schematic sectional drawing which shows another example of the layer structure of an optical laminated body. It is a schematic sectional drawing which shows another example of the layer structure of an optical laminated body.

<Optical laminate>
FIG. 1 is a schematic sectional view showing an example of the optical laminate according to the present invention. As shown in FIG. 1, the optical layered body according to the present invention may include an optical film 10, an adhesive layer 20, and a metal layer 30 in this order, and may further include a substrate 40. This optical layered body is a pressure-sensitive adhesive layer-attached optical film 1 including an optical film 10 on a metal layer 30 formed on a substrate 40 and a pressure-sensitive adhesive layer 20 laminated on at least one surface thereof. The adhesive layer 20 may be attached via the adhesive layer 20.

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

The optical film 10 may be a single-layer optical film or a multi-layer optical film. The pressure-sensitive adhesive layer 20 is composed of a pressure-sensitive adhesive composition containing a (meth)acrylic resin (A), an isocyanate crosslinking agent (B), a silane compound (C), and an ionic compound (D). This pressure-sensitive adhesive composition may further contain other components. In the present specification, “(meth)acrylic” means at least one selected from the group consisting of acrylic and methacrylic. The same applies to “(meth)acrylate” and “(meth)acryloyl”.

[1] Optical Film The optical film 10 included in the optical laminate according to the present invention is an optical member constituting the pressure-sensitive adhesive layer-attached optical film 1, and various optical films that can be incorporated in an image display device such as a liquid crystal display device. (A film having optical characteristics). The optical film 10 may be a single-layer optical film or a multi-layer optical film. Specific examples of the optical film having a single-layer structure include optical functional films such as a retardation film, a brightness enhancement film, an antiglare film, an antireflection film, a diffusion film, and a light collecting film, in addition to the polarizer. Specific examples of the optical film having a multilayer structure include a polarizing plate and a retardation plate. In the present specification, a polarizing plate refers to a polarizer having a resin film or a resin layer laminated on at least one surface thereof. The retardation plate is a retardation film having a resin film or a resin layer laminated on at least one surface thereof. The optical film 10 is preferably a polarizing plate, a polarizer, a retardation plate or a retardation film, and more preferably a polarizing plate or a polarizer.

[1-1] Polarizing Plate FIGS. 2 and 3 are schematic cross-sectional views showing examples of the layer structure of the polarizing plate. The polarizing plate 10a shown in FIG. 2 is a single-sided protective polarizing plate in which the first resin film 3 is laminated and laminated on one surface of the polarizer 2, and the polarizing plate 10b shown in FIG. It is a double-sided protective polarizing plate in which the second resin film 4 is further laminated and laminated on the other surface. The first and second resin films 3 and 4 can be attached to the polarizer 2 via an adhesive layer or an adhesive layer (not shown). The polarizing plates 10a and 10b may include films and layers other than the first and second resin films 3 and 4.

An example 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 is 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 has the polarizing plate 10b shown in FIG. This is an example used as the optical film 10.

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

The polyvinyl alcohol-based resin can be obtained by saponifying a polyvinyl acetate-based resin. Examples of the polyvinyl acetate-based resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and a copolymer of vinyl acetate and a monomer copolymerizable with vinyl acetate. Examples of the monomer copolymerizable with vinyl acetate include unsaturated carboxylic acid, olefin, vinyl ether, unsaturated sulfonic acid, and (meth)acrylamide having an ammonium group.

The saponification degree 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 degree of polymerization of the polyvinyl alcohol-based resin is usually 1000 to 10000, preferably 1500 to 5000. The average degree of polymerization of the polyvinyl alcohol resin can be determined according to JIS K 6726.

Usually, a film made of polyvinyl alcohol resin is used as a raw film of the polarizer 2. The polyvinyl alcohol resin can be formed into a film by a known method. The thickness of the raw film is usually 1 to 150 μm, and preferably 10 μm or more in consideration of ease of stretching and the like.

The polarizer 2 includes, for example, a step of uniaxially stretching a raw film, a step of dyeing a film with a dichroic dye to adsorb the dichroic dye, a step of treating the film with an aqueous boric acid solution, and The film is washed with water, and finally dried to be manufactured. The thickness of the polarizer 2 is usually 1 to 30 μm, and preferably 20 μm or less, more preferably 15 μm or less, and further preferably 10 μm or less from the viewpoint of thinning the pressure-sensitive adhesive layer-attached optical film 1.

The polarizer 2 formed by adsorbing and orienting a dichroic dye on a polyvinyl alcohol-based resin film uses 1) a single film of a polyvinyl alcohol-based resin film as a raw film, and a uniaxial stretching treatment and dichroism on this film. In addition to the method of dyeing a dye, 2) a base film having a polyvinyl alcohol-based resin layer is obtained by applying a coating solution (aqueous solution, etc.) containing a polyvinyl alcohol-based resin to the base film and drying it. Then, this can also be obtained by a method in which this is uniaxially stretched together with the substrate film, the polyvinyl alcohol resin layer after stretching is dyed with a dichroic dye, and then the substrate film is peeled off. As the base film, a film made of a thermoplastic resin similar to the thermoplastic resins that can form the first and second resin films 3 and 4 described below can be used, and preferably a polyester resin such as polyethylene terephthalate. , A polycarbonate resin, a cellulose resin such as triacetyl cellulose, a cyclic polyolefin resin such as a norbornene resin, and a polystyrene resin. According to the method 2), the thin film polarizer 2 can be easily manufactured, and for example, the polarizer 2 having a thickness of 7 μm or less can be easily manufactured.

The first and second resin films 3 and 4 are independently transparent, preferably optically transparent thermoplastic resin, for example, chain polyolefin resin (polyethylene resin, polypropylene resin, etc.). Polyolefin resin such as cyclic polyolefin resin (norbornene resin etc.); Cellulose resin (cellulose ester resin etc.); Polyester resin (polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate etc.); Polycarbonate resin; The film may be a (meth)acrylic resin; a polystyrene resin; a polyetheretherketone resin; a polysulfone resin, or a mixture or copolymer of these. Among them, the first and second resin films 3 and 4 are each made of a resin selected from the group consisting of a cyclic polyolefin resin, a polycarbonate resin, a cellulose resin, a polyester resin, and a (meth)acrylic resin. It is preferable that the resin is selected from the group consisting of a cellulose-based resin and a cyclic polyolefin-based resin.

Examples of the chain polyolefin resin include homopolymers of chain olefins such as polyethylene resin and polypropylene resin, and copolymers of two or more chain olefins.

The cyclic polyolefin-based resin is a general term for resins containing cyclic olefins represented by norbornene, tetracyclododecene (alias: dimethanooctahydronaphthalene) or derivatives thereof as polymerized units. Specific examples of the cyclic polyolefin resin include a ring-opening (co)polymer of a cyclic olefin and a hydrogenated product thereof, an addition polymer of a cyclic olefin, a cyclic olefin and a chain olefin such as ethylene or propylene, or a vinyl group. Examples thereof include copolymers with aromatic compounds, and modified (co)polymers obtained by modifying these with unsaturated carboxylic acids or their derivatives. Above all, 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 resin is preferably a cellulose ester resin, that is, a partially or completely esterified product of cellulose, and examples thereof include cellulose acetate, propionate, butyrate, and mixed esters thereof. Among them, triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, cellulose acetate butyrate and the like are preferably used.

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

The polycarbonate resin is a polyester formed from carbonic acid and glycol or bisphenol. Among them, aromatic polycarbonate having diphenylalkane in the molecular chain is preferably used from the viewpoint of heat resistance, weather resistance and acid resistance. As polycarbonate, 2,2-bis(4-hydroxyphenyl)propane (also known as bisphenol A), 2,2-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1 Examples include polycarbonates derived from bisphenols such as -bis(4-hydroxyphenyl)isobutane and 1,1-bis(4-hydroxyphenyl)ethane.

The (meth)acrylic resin that can form the first and second resin films 3 and 4 can be a polymer having a structural unit derived from methacrylic acid ester as a main component (for example, containing 50% by weight or more). It is preferably a copolymer in which other copolymerization components are copolymerized. The (meth)acrylic resin may contain two or more kinds of structural units derived from methacrylic acid ester. Examples of the methacrylic acid ester include C ₁ -C ₄ alkyl esters of methacrylic acid such as methyl methacrylate, ethyl methacrylate and butyl methacrylate.

Acrylic acid ester is mentioned as a copolymerization component which can be copolymerized with a methacrylic acid ester. The acrylic ester is preferably a C ₁ -C ₈ alkyl ester of acrylic acid such as methyl acrylate, ethyl acrylate, butyl acrylate, 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, α-methylstyrene, vinyltoluene; and vinyl cyan compounds such as (meth)acrylonitrile. Unsaturated acids such as maleic anhydride and citraconic anhydride; unsaturated imides such as phenylmaleimide, cyclohexylmaleimide, etc., having one polymerizable carbon-carbon double bond in the molecule, other than acrylic acid ester A compound can be mentioned. A compound having two or more polymerizable carbon-carbon double bonds in the molecule may be used as a copolymerization component. The copolymerization component may be used alone or in combination of two or more.

The (meth)acrylic resin may have a ring structure in the polymer main chain, from the viewpoint of enhancing 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, specific examples of cyclic imide structure include glutarimide structure and succinimide structure, and specific examples of lactone ring structure include butyrolactone ring. A structure and a valerolactone ring structure are mentioned, respectively.

The (meth)acrylic resin may contain acrylic rubber particles from the viewpoint of film-forming property on the film, impact resistance of the film, and the like. Acrylic rubber particles are particles having an elastic polymer mainly composed of an acrylic ester as an essential component, and have a single-layer structure consisting essentially of this elastic polymer or a single layer of elastic polymer. A multilayer structure having As an example of the elastic polymer, a crosslinked elastic copolymer in which an alkyl acrylate as a main component is copolymerized with another copolymerizable vinyl monomer and a crosslinkable monomer is mentioned. Examples of the alkyl acrylate 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 alkyl group preferably has 4 or more carbon atoms.

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

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. When the content of the acrylic rubber particles is too large, the surface hardness of the film may be lowered, and the solvent resistance to the organic solvent in the surface treatment agent may be lowered when the film is subjected to the surface treatment. 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 the usual additives in the technical field of the present invention. Specific examples of the additive include, for example, an ultraviolet absorber, an infrared absorber, an organic dye, a pigment, an inorganic pigment, an antioxidant, an antistatic agent, a surfactant, a lubricant, a dispersant, a heat stabilizer, and the like. ..

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

Each of the first and second resin films 3 and 4 may be either an unstretched film or a uniaxially or biaxially stretched film. The biaxial stretching may be simultaneous biaxial stretching in which two stretching directions are simultaneously performed, or sequential biaxial stretching in which the stretching is performed 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 plays a role of protecting the polarizer 2, or a protective film that also has an optical function such as a retardation film described later. You can also The retardation film is an optical film exhibiting optical anisotropy. For example, by stretching (uniaxially stretching or biaxially stretching) a film made of the above thermoplastic resin, or by forming a liquid crystal layer or the like on the thermoplastic resin film, an arbitrary retardation value is imparted. It can be a retardation film.

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

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

The thickness of each of the first resin film 3 and the second resin film 4 is usually 1 to 150 μm, preferably 5 to 100 μm, and more preferably 5 to 60 μm. The thickness may be 50 μm or less, further 30 μm or less. Reducing the thickness of the first and second resin films 3 and 4 is intended to reduce the thickness of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, and thus to a liquid crystal display device including the pressure-sensitive adhesive layer-carrying optical film 1 or the optical laminate. Is advantageous for thinning.

In particular, in the case of a small or medium-sized polarizing plate such as a smartphone or a tablet terminal, a thin film having a thickness of 30 μm or less is 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 has a weak force for suppressing the contracting force of the polarizer 2 and tends to have insufficient durability. According to the present invention, it is possible to provide the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, which have good durability even when such a polarizing plate is used as the optical film 10. The durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate means, for example, in a high temperature environment, a high temperature and high humidity environment, an environment in which high temperature and low temperature are repeated, and the like, the pressure sensitive adhesive layer 20 and the optics adjacent thereto. This is a property that can prevent problems such as floating and peeling at the interface with the member and foaming of the pressure-sensitive adhesive layer 20.

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

The first and second resin films 3 and 4 can be attached to the polarizer 2 via an adhesive layer or a pressure-sensitive 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 an adhesive composed of a polyvinyl alcohol-based resin aqueous solution and a water-based two-component urethane-based emulsion adhesive. Above all, a water-based adhesive composed of a polyvinyl alcohol-based resin aqueous solution is preferably used. Examples of the polyvinyl alcohol-based resin include vinyl alcohol homopolymers obtained by saponifying polyvinyl acetate, which is a homopolymer of vinyl acetate, as well as copolymers of vinyl acetate and other monomers copolymerizable therewith. A polyvinyl alcohol-based copolymer obtained by saponifying a polymer, a modified polyvinyl alcohol-based polymer obtained by partially modifying a hydroxyl group thereof, or the like can be used. The water-based adhesive can contain a crosslinking agent such as an aldehyde compound, an epoxy compound, a melamine compound, a methylol compound, an isocyanate compound, an amine compound, and a polyvalent metal salt.

When a water-based adhesive is used, after the polarizer 2 and the first and second resin films 3 and 4 are bonded, a drying step is performed to remove water contained in the water-based adhesive. Is preferred. After the drying step, a curing step of curing at a temperature of about 20 to 45° C. may be provided.

The active energy ray-curable adhesive refers to an adhesive that is cured by irradiation with active energy rays such as ultraviolet rays and electron beams, for example, a curable composition containing a polymerizable compound and a photopolymerization initiator, light. Examples thereof include a curable composition containing a reactive resin, a curable composition containing a binder resin and a photoreactive crosslinking agent, and the like. UV curable adhesives are preferred. 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 the photopolymerizable monomers. .. Examples of the photopolymerization initiator include those containing substances that generate active species such as neutral radicals, anion radicals, and cation radicals upon irradiation 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, a photocurable (meth)acrylic monomer and a photocurable composition A curable composition containing a radical polymerization initiator, or a mixture of these curable compositions can be preferably used.

When an active energy ray-curable adhesive is used, the polarizer 2 and the first and second resin films 3 and 4 are bonded together, and then a drying step is performed if necessary, followed by irradiation with active energy rays. Then, a curing step of curing the active energy ray-curable adhesive is performed. The light source of the active energy ray is not particularly limited, but ultraviolet rays having a light emission distribution at a wavelength of 400 nm or less are preferable, and specifically, low pressure mercury lamp, medium pressure mercury lamp, high pressure mercury lamp, ultra high pressure mercury lamp, chemical lamp, black light lamp, micro A wave excitation mercury lamp, a metal halide lamp, etc. can be used.

In laminating the polarizer 2 and the first and second resin films 3 and 4, at least one of these laminating surfaces is subjected to a surface activation treatment such as saponification treatment, corona treatment or plasma treatment. be able to. When resin films are laminated on both surfaces of the polarizer 2, the adhesive for laminating these resin films may be the same kind of adhesive or different kinds of adhesive.

The polarizing plates 10a and 10b may further include other films or layers. Specific examples thereof include a brightness enhancement film, an antiglare film, an antireflection film, a diffusion film, a light condensing film, a pressure-sensitive adhesive layer other than the pressure-sensitive adhesive layer 20, a coating layer, a protective film, and the like, in addition to the retardation film described below. .. The protect film is a film used for the purpose of protecting the surface of the optical film 10 such as a polarizing plate from scratches and stains, and is peeled off after the optical film 1 with the pressure-sensitive adhesive layer is stuck on the metal layer 30, for example. It is customary to

The protect film is usually composed of a base film and an adhesive layer laminated on the base film. The base film is composed of a thermoplastic resin, for example, a polyolefin resin such as polyethylene resin or polypropylene resin; a polyester resin such as polyethylene terephthalate or polyethylene naphthalate; a polycarbonate resin; a (meth)acrylic resin or the like. be able to.

[1-2] Retardation Plate The retardation film included in the retardation plate is an optical film exhibiting optical anisotropy as described above, and can be used for the first and second resin films 3 and 4. In addition to the thermoplastic resins exemplified above as, for example, polyvinyl alcohol-based resin, polyarylate-based resin, polyimide-based resin, polyether sulfone-based resin, polyvinylidene fluoride/polymethylmethacrylate-based resin, liquid crystal polyester-based resin, It can be a stretched film obtained by stretching a resin film made of a saponified ethylene-vinyl acetate copolymer, a polyvinyl chloride resin, or the like about 1.01 to 6 times. Among them, a polycarbonate-based resin film, a cyclic olefin-based resin film, a (meth)acrylic-based resin film, or a cellulose-based resin film is preferably a uniaxially or biaxially stretched film. Further, in the present specification, a zero retardation film is also included in the retardation film (however, it can also be used as a protective film). In addition, a film called a uniaxial retardation film, a wide viewing angle retardation film, a low photoelasticity retardation film, or the like is also applicable as the retardation film.

The zero Letters retardation film in-plane retardation value R _e and the thickness direction retardation R _th means a film are both -15～15Nm. This retardation film is suitably used for an IPS mode liquid crystal display device. Plane retardation value R _e and the thickness direction retardation R _th are preferably both -10～10Nm, more preferably both -5～5Nm. The in-plane retardation value _Re and the thickness direction retardation value _Rth 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 respectively represented by the following formulas:
_{R e = (n x -n y} ) × d
R _th =[(n _x + _ny )/2−n _z ]×d
Is defined by In the formula, n _x is the refractive index in the slow axis direction (x axis direction) in the film plane, and n _y is the fast axis direction in the film plane (y axis direction orthogonal to the x axis in the plane) Is the refractive index, _nz is the refractive index in the film thickness direction (z-axis direction perpendicular to the film surface), and d is the film thickness.

As the zero retardation film, for example, a resin film made of a polyolefin resin such as a cellulose resin, a chain polyolefin resin and a cyclic polyolefin resin, a polyethylene terephthalate resin or a (meth)acrylic resin can be used. In particular, a cellulose-based resin, a polyolefin-based resin, or a (meth)acrylic-based resin is preferably used because the retardation value can be easily controlled and easily obtained.

Further, a film in which optical anisotropy is expressed by coating/orientation of a liquid crystal compound or a film in which optical anisotropy is expressed by coating of an inorganic layered compound can be used as the retardation film. Such a retardation film is referred to as a temperature compensation type retardation film, and a rod-shaped liquid crystal sold under the trade name of “NH film” by JX Nippon Mining & Energy Corporation is tilt-aligned. Film, a film with a disc-shaped liquid crystal that is sold under the brand name of "WV film" from Fujifilm Corporation, and a complete biaxial marketed under the brand name of "VAC Film" from Sumitomo Chemical Co., Ltd. There are orientation type films, and biaxial orientation type films which are also sold by Sumitomo Chemical Co., Ltd. under the trade name of "new VAC film".

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

[2] Adhesive Layer The adhesive layer 20 disposed between the optical film 10 and the metal layer 30 includes a (meth)acrylic resin (A), an isocyanate crosslinking agent (B), a silane compound (C), And an adhesive composition containing an ionic compound (D). In this pressure-sensitive adhesive composition, the ionic compound (D) has the following formula (I):

Is an ionic compound represented by. In the formula, A ⁺ represents an organic or inorganic cation.
According to the pressure-sensitive adhesive layer 20 composed of the above-mentioned pressure-sensitive adhesive composition, corrosion of the metal layer 30 can be suppressed in the optical layered body having the structure including the pressure-sensitive adhesive layer 20 and the metal layer 30, and the pressure-sensitive adhesive is also provided. The durability of the layered optical film 1 and the optical laminate can be improved. Further, according to the pressure-sensitive adhesive layer 20 composed of the above-mentioned pressure-sensitive adhesive composition, the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate have a constitution in which the pressure-sensitive adhesive layer 20 is directly bonded to the polarizer 2. Even if there is, good optical durability can be exhibited.

The thickness of the pressure-sensitive adhesive layer 20 is usually 2 to 40 μm, and preferably 5 to 30 μm from the viewpoint of durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, reworkability of the pressure-sensitive adhesive layer-carrying optical film 1. And more preferably 10 to 25 μm. Further, if the thickness of the pressure-sensitive adhesive layer 20 is 10 μm or more, the followability of the pressure-sensitive adhesive layer 20 with respect to the dimensional change of the optical film 10 becomes good, and if it is 25 μm or less, the reworkability becomes good.

The pressure-sensitive adhesive layer 20 preferably has a storage elastic modulus of 0.1 to 5 MPa in the temperature range of 23 to 80°C. Thereby, the durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate can be more effectively enhanced. The phrase “showing a storage elastic modulus of 0.1 to 5 MPa in a temperature range of 23 to 80° C.” means that the storage elastic modulus is a value within the above range at any temperature in this range. Since the storage elastic modulus usually gradually decreases as the temperature rises, if the storage elastic moduli at 23° C. and 80° C. are both within the above range, the storage elastic modulus within the above range is exhibited at the temperature of this range. Can be seen. The storage elastic modulus of the pressure-sensitive adhesive layer 20 can be measured using a commercially available viscoelasticity measuring device, for example, a viscoelasticity measuring device “DYNAMIC ANALYZER RDA II” manufactured by REOMETRIC.

[2-1] (Meth)acrylic resin (A)
The (meth)acrylic resin (A) is a polymer or copolymer containing a structural unit derived from a (meth)acrylic monomer as a main component (preferably containing 50% by weight or more). The (meth)acrylic monomer includes, for example, a monomer having a (meth)acryloyl group, and preferably an alkyl(meth)acrylate. The alkyl group contained in the alkyl (meth)acrylate has preferably 1 to 14, more preferably 1 to 12 and even more preferably 1 to 8 carbon atoms, and may be linear, branched or cyclic. As the alkyl (meth)acrylate, it is also possible to use a substituent-containing alkyl (meth)acrylate such as a substituent-containing alkyl acrylate in which a substituent is introduced into the alkyl group described later. 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, 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, isobornyl (meth)acrylate, n- and i-dodecyl (meth)acrylate, stearyl (meth)acrylate and the like. Including.

The (meth)acrylic resin (A) is a structural unit derived from an alkyl acrylate (a1) whose homopolymer glass transition temperature Tg is lower than 0° C., and an alkyl acrylate (a2) whose homopolymer Tg is 0° C. or higher. It is preferable to contain the derived structural unit. This is advantageous in improving the metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate. As the Tg of the homopolymer of alkyl acrylate, for example, literature values such as POLYMER HANDBOOK (Wiley-Interscience) can be adopted.

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-heptyl acrylate, n-. And i-octyl acrylate, 2-ethylhexyl acrylate, n- and i-nonyl acrylate, n- and i-decyl acrylate, and n-dodecyl acrylate, etc. .. 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 the alkyl acrylate having an alkyl group having about 2 to 12 carbon atoms can be given. The substituent of the substituent-containing alkyl acrylate is a group that replaces a hydrogen atom of the 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. Among them, the alkyl acrylate (a1) preferably contains one kind or two or more kinds selected from ethyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate. The alkyl acrylate (a1) preferably contains n-butyl acrylate from the viewpoint of the followability of the pressure-sensitive adhesive layer 20 of the pressure-sensitive adhesive layer-attached optical film 1 to the optical film 10 and 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, isobornyl 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, the alkyl acrylate (a2) preferably contains methyl acrylate, cyclohexyl acrylate, isobornyl acrylate and the like, and more preferably contains methyl acrylate, from the viewpoint of metal corrosion resistance and durability.

The content of the structural unit derived from the alkyl acrylate (a2) in the (meth)acrylic resin (A) is (meth) from the viewpoint of metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate. In 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, further preferably 20 parts by weight or more, and particularly preferably 25 parts by weight. It is more than part by weight. Further, from the viewpoint of the ability of the pressure-sensitive adhesive layer 20 to follow the optical film 10 and reworkability, the content of the structural unit derived from the alkyl acrylate (a2) is preferably 70 parts by weight or less, and more preferably 60 parts by weight or less. And more preferably 50 parts by weight or less.

The (meth)acrylic resin (A) may contain a structural unit derived from a monomer other than the alkyl acrylates (a1) and (a2). The (meth)acrylic resin (A) may include only one type of structural unit derived from the other monomer, or may include two or more types thereof. Specific examples of other monomers are shown below.

1) A monomer having a polar functional group.
Examples of the monomer having a polar functional group include (meth)acrylates having a substituent such as a hydroxy group, a carboxyl group, a substituted or unsubstituted amino group, and a heterocyclic group such as an epoxy group. 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, vinyl pyridine, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, glycidyl (meth)acrylate, 2,5-dihydrofuran Monomers having a heterocyclic group such as; aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate and the like having substituted or unsubstituted amino groups A monomer having a carboxyl group such as (meth)acrylic acid and carboxyethyl (meth)acrylate. Among them, a monomer having a hydroxy group is preferable, and a (meth)acrylate having a hydroxy group is more preferable in terms of reactivity between the (meth)acrylic resin (A) and the crosslinking agent.

Although it may contain the above-mentioned other monomer having a polar functional group in addition to the (meth)acrylate having a hydroxy group, it enhances the peeling force of the separate film that can be laminated on the outer surface of the pressure-sensitive adhesive layer 20. From the viewpoint of prevention, it is preferable that the monomer having an amino group is not substantially contained. Further, from the viewpoint of enhancing the corrosion resistance to ITO, it is preferable that the monomer having a carboxyl group is not substantially contained. Here, "not substantially containing" means that it is 0.1 part by weight or less in 100 parts by weight of all the constituent units constituting the (meth)acrylic resin (A).

2) An acrylamide monomer.
For example, N-methylol acrylamide, 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-dimethylaminopropyl)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, 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[ Synonyms: N-(2-isobutoxyethyl)acrylamide], N-(2-butoxyethyl)acrylamide, N-[2-(1,1-dimethylethoxy)ethyl]acrylamide and the like. Among them, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N-(butoxymethyl)acrylamide and N-(2-methylpropoxymethyl)acrylamide are preferably used.

3) Methacrylate, that is, methacrylic acid ester.
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; methacrylic acid such as isobutyl methacrylate, 2-ethylhexyl methacrylate and i-octyl methacrylate. A branched alkyl ester of methacrylic acid such as isobornyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, cyclododecyl methacrylate, methylcyclohexyl methacrylate, trimethylcyclohexyl methacrylate, t-butylcyclohexyl methacrylate, and cyclohexylphenyl methacrylate. Alkyl ester; Alkoxyalkyl ester of methacrylic acid such as 2-methoxyethyl methacrylate and ethoxymethyl methacrylate; Methacrylic acid aralkyl ester such as benzyl methacrylate; 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2- Alkyl ester of methacrylic acid having a hydroxyl group such as (2-hydroxyethoxy)ethyl methacrylate, 2-chloro-2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monomethacrylate; aminoethyl methacrylate, N, An alkyl ester of methacrylic acid having a substituted or unsubstituted amino group such as N-dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylate; 2-phenoxyethyl methacrylate, 2-(2-phenoxyethoxy)ethyl methacrylate, (meth)acrylic acid Ethylene oxide modified nonylphenol ester, methacrylic acid ester having a phenoxyethyl group such as 2-(o-phenylphenoxy)ethyl methacrylate, and the like.

4) Methacrylamide monomers.
For example, a methacrylamide monomer corresponding to the acrylamide monomer described in 1) above.

5) Styrene-based monomer.
For example, styrene; alkylstyrene such as methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene, octylstyrene; fluorostyrene, chlorostyrene, bromostyrene, Halogenated styrenes such as dibromostyrene and iodostyrene; nitrostyrene; acetylstyrene; methoxystyrene; divinylbenzene and the like.

6) Vinyl monomer.
For example, fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate; vinyl halides such as vinyl chloride and vinyl bromide; vinylidene halide such as vinylidene chloride; vinyl pyridine. , Nitrogen-containing aromatic vinyls such as 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-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth) ) Monomers having two (meth)acryloyl groups in the molecule such as acrylate, tetraethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate; molecules such as trimethylolpropane tri(meth)acrylate Monomers and the like having three (meth)acryloyl groups inside.

As described above, the (meth)acrylic resin (A) is a structural unit derived from an alkyl (meth)acrylate from the viewpoint of durability and metal corrosion resistance of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate. In addition, 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 in 100 parts by weight of all constituent units constituting the (meth)acrylic resin (A), It is more preferably 0.25 to 5 parts by weight, and even more preferably 0.5 to 5 parts by weight.

From the viewpoint of reworkability of the pressure-sensitive adhesive layer-attached optical film 1, the (meth)acrylic resin (A) is derived from a methacrylic monomer such as a methacrylate (methacrylic acid ester) or a methacrylamide monomer. The content of the constituent unit is preferably small, and specifically, the content of the constituent unit is preferably 10 parts by weight in 100 parts by weight of all the constituent units constituting the (meth)acrylic resin (A). Or less, more preferably 5 parts by weight or less, and it is even more preferable that the structural unit is not substantially contained (0.1 parts by weight or less).

The (meth)acrylic resin (A) preferably has a single peak in the range of the weight average molecular weight Mw of 1,000 to 2,500,000 on the emission curve in gel permeation chromatography (GPC), and the weight average molecular weight of Mw of 1,000 to 2,500,000. It is more preferable to have a single peak in the range and to contain the structural units derived from the alkyl acrylates (a1) and (a2). The pressure-sensitive adhesive layer 20 containing such a (meth)acrylic resin (A) as a base polymer is advantageous in enhancing the durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate. When the number of peaks in the Mw range is 2 or more, sufficient durability tends to be unobtainable.

When obtaining the peak number of the GPC emission curve in the range of Mw 1000 to 2.5 million, the emission curve is acquired according to the GPC measurement conditions described in the section of Examples. "Having a single peak" in the above range of the obtained emission curve means having only one maximum value in the range of Mw of 1,000 to 2,500,000. In the present specification, a GPC emission curve having an S/N ratio of 30 or more is defined as a peak.

The Mw of the (meth)acrylic resin (A) in terms of standard polystyrene by GPC is preferably in the range of 500,000 to 2,500,000, and more preferably in the range of 600,000 to 2,000,000. When the Mw is 500,000 or more, it is advantageous for improving the metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, and the reworkability of the pressure-sensitive adhesive layer-carrying optical film 1 also tends to improve. is there. Further, when the Mw is 2,500,000 or less, the followability of the pressure-sensitive adhesive layer 20 with respect to the dimensional change of the optical film 10 becomes good. The molecular weight distribution represented by the ratio Mw/Mn of the weight average molecular weight Mw and the number average molecular weight Mn is usually 2 to 10. The 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 form a solution having a concentration of 20% by weight, the viscosity at 25° C. is preferably 20 Pa·s or less, and 0.1 to 7 Pa·s. Is more preferable. The viscosity in this range is advantageous for improving the durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, and for reworking the pressure-sensitive adhesive layer-carrying optical film 1. The viscosity can be measured by a Brookfield viscometer.

The glass transition temperature Tg of the (meth)acrylic resin (A) measured by a differential scanning calorimeter (DSC) is preferably −60 to −10° C., and more preferably −55 to −15° C. preferable. Tg in this range is advantageous for improving the metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate.

The pressure-sensitive adhesive composition may contain two or more kinds of (meth)acrylic resins belonging to the (meth)acrylic resin (A). Further, the pressure-sensitive adhesive composition may contain another (meth)acrylic resin different from the (meth)acrylic resin (A). However, from the viewpoint of metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, the content of the (meth)acrylic resin (A) is in the total of all (meth)acrylic resins. It is preferably 70% by weight or more, more preferably 80% by weight or more, further preferably 90% by weight or more, and the pressure-sensitive adhesive composition contains only the (meth)acrylic resin (A) as a base polymer. It is particularly preferable to contain.

The (meth)acrylic resin (A) and other (meth)acrylic resins that can be used in combination as necessary can be prepared by a known method such as a solution polymerization method, a bulk polymerization method, a suspension polymerization method or an emulsion polymerization method. It can be manufactured. A polymerization initiator is usually used in the production of the (meth)acrylic resin. The polymerization initiator is used in an amount of about 0.001 to 5 parts by weight based on 100 parts by weight of all the monomers used for producing the (meth)acrylic resin. Further, the (meth)acrylic resin may be produced by a method of causing polymerization to proceed with active energy rays such as ultraviolet rays.

As the polymerization initiator, a thermal polymerization initiator, a photopolymerization initiator or the like is used. Examples of the photopolymerization initiator include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone. As the 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'-azobis(2-methylpropio) Azo), azo compounds such as 2,2′-azobis(2-hydroxymethylpropionitrile); lauryl peroxide, t-butyl hydroperoxide, benzoyl peroxide, t-butyl peroxybenzoate, cumene hydroper. Organics such as oxides, diisopropyl peroxydicarbonate, dipropyl peroxydicarbonate, t-butyl peroxy neodecanoate, t-butyl peroxypivalate, (3,5,5-trimethylhexanoyl) peroxide Peroxides: Inorganic peroxides such as potassium persulfate, ammonium persulfate, hydrogen peroxide and the like can be mentioned. Further, a redox type initiator in which a peroxide and a reducing agent are used in combination may also be used as the polymerization initiator.

Among the methods described above, the solution polymerization method is preferable as the method for producing the (meth)acrylic resin. An example of the solution polymerization method is to mix the monomers to be used and an organic solvent, add a thermal polymerization initiator under a nitrogen atmosphere, and at 40 to 90° C., preferably at 50 to 80° C. for 3 to 15 hours. It is about stirring. In order to control the reaction, a monomer or a thermal polymerization initiator may be added continuously or intermittently during the polymerization, or may be added in a state of being dissolved in an organic solvent. Examples of the organic solvent 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; acetone, methyl ethyl ketone, methyl isobutyl ketone and the like. Ketones and the like can be used.

[2-2] Isocyanate-based cross-linking agent (B)
The pressure-sensitive adhesive composition contains an isocyanate crosslinking agent (B). By using the isocyanate-based cross-linking agent (B) as a cross-linking agent, it is possible to enhance metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate. The isocyanate crosslinking agent (B) may be used alone or in combination of two or more.

The isocyanate-based crosslinking agent (B) is a compound having at least two isocyanato groups (-NCO) in the molecule, and specifically, tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated Examples thereof include xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, triphenylmethane triisocyanate and the like. The isocyanate cross-linking agent (B) is a polyhydric alcohol compound adduct of these isocyanate compounds (for example, an adduct of glycerol or trimethylolpropane), an isocyanurate compound, a buret-type compound, and further a polyether polyol, a polyester polyol, an acryl. It may be a derivative such as a urethane prepolymer type isocyanate compound which is subjected to an addition reaction with polyol, polybutadiene polyol, polyisoprene polyol or the like. Among the above, tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate or polyhydric alcohol compound adducts of those isocyanate compounds are particularly preferable, from the viewpoint of durability of the pressure-sensitive adhesive layer-attached optical film 1 and the optical laminate, xylylene A diisocyanate or a polyhydric alcohol compound adduct thereof is more preferable.

The content of the isocyanate crosslinking agent (B) is preferably 0.08 to 2.5 parts by weight, more preferably 0.1 to 2 parts by weight, relative to 100 parts by weight of the (meth)acrylic resin (A). Parts by weight (for example, 1 part by weight or less). When the content of the isocyanate cross-linking agent (B) is in this range, it is advantageous in achieving both metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate.

In the pressure-sensitive adhesive composition, the isocyanate-based cross-linking agent (B) may be used in combination with other cross-linking agents such as an epoxy compound, an aziridine compound, a metal chelate compound, and a peroxide. However, the pressure-sensitive adhesive layer-attached optical film 1 From the viewpoint of metal corrosion resistance and durability of the optical layered body, the pressure-sensitive adhesive composition preferably contains only the isocyanate-based cross-linking agent (B) as a cross-linking agent, and particularly substantially free of peroxide. .. Here, “not substantially containing” means that the content is 0.01 parts by weight or less based on 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). Thereby, the adhesiveness between the pressure-sensitive adhesive layer 20 and the metal layer 30, the glass substrate or the like can be enhanced. 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, 3-glycidoxypropyltriethoxysilane and 3 -Glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylethoxydimethylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, Examples thereof include 3-methacryloyloxypropyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane.

The silane compound (C) may include a silicone oligomer type compound. A specific example of the silicone oligomer will be described below in the form of a combination of monomers.

3-mercaptopropyltrimethoxysilane-tetramethoxysilane oligomer,
3-mercaptopropyltrimethoxysilane-tetraethoxysilane oligomer,
3-mercaptopropyltriethoxysilane-tetramethoxysilane oligomer,
A mercaptopropyl group-containing oligomer such as 3-mercaptopropyltriethoxysilane-tetraethoxysilane oligomer;
Mercaptomethyltrimethoxysilane-tetramethoxysilane oligomer,
Mercaptomethyltrimethoxysilane-tetraethoxysilane oligomer,
Mercaptomethyltriethoxysilane-tetramethoxysilane oligomer,
Mercaptomethyl group-containing oligomers such as mercaptomethyltriethoxysilane-tetraethoxysilane oligomers;
3-glydidoxypropyltrimethoxysilane-tetramethoxysilane copolymer,
3-glycidoxypropyltrimethoxysilane-tetraethoxysilane copolymer,
3-glycidoxypropyltriethoxysilane-tetramethoxysilane copolymer,
3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer,
3-glydidoxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-glydidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-glydidoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,
Copolymers containing 3-glycidoxypropyl groups such as 3-glydidoxypropylmethyldiethoxysilane-tetraethoxysilane copolymers;
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,
A methacryloyloxypropyl group-containing oligomer such as 3-methacryloyloxypropylmethyldiethoxysilane-tetraethoxysilane oligomer;
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,
Acryloyloxypropyl group-containing oligomer such as 3-acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane oligomer;
Vinyltrimethoxysilane-tetramethoxysilane oligomer,
Vinyltrimethoxysilane-tetraethoxysilane oligomer,
Vinyltriethoxysilane-tetramethoxysilane oligomer,
Vinyltriethoxysilane-tetraethoxysilane oligomer,
Vinylmethyldimethoxysilane-tetramethoxysilane oligomer,
Vinylmethyldimethoxysilane-tetraethoxysilane oligomer,
Vinylmethyldiethoxysilane-tetramethoxysilane oligomer,
Vinyl group-containing oligomers such as vinylmethyldiethoxysilane-tetraethoxysilane oligomers;
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,
Amino group-containing copolymers such as 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer.

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

[2-4] Ionic compound (D)
The adhesive composition contains an ionic compound (D). The ionic compound (D) has the following formula (I):

Is an ionic compound represented by. 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 or more ionic compounds (D).

In the above formula (I), A ⁺ represents an organic or inorganic cation. Specific examples of the organic cation include a pyridinium cation, an imidazolium cation, a piperidinium cation, a pyrrolidinium cation, a tetrahydropyridinium cation, a dihydropyridinium cation, a tetrahydropyrimidinium cation, a dihydropyrimidinium cation, a pyrazolium cation, and a pyrazolium cation. Includes zolinium cations, ammonium cations, sulfonium cations, phosphonium cations and the like. The organic cation may have a substituent. Specific examples of the inorganic cation include alkali metal ions such as lithium cation [Li ⁺ ], sodium cation [Na ⁺ ], potassium cation [K ⁺ ] and cesium cation [Cs ⁺ ]; beryllium cation [Be ²⁺ ], magnesium cation. It contains alkaline earth metal ions such as [Mg ²⁺ ] and calcium cation [Ca ²⁺ ].

Among them, A ⁺ is preferably an organic cation from the viewpoint of compatibility with the (meth)acrylic resin (A), and is a pyridinium cation, an imidazolium cation, a piperidinium cation, or a pyrrolidinium from the viewpoint of antistatic performance. Nitrogen atom-containing organic cations (having a substituent), such as aluminum cation, tetrahydropyridinium cation, dihydropyridinium cation, tetrahydropyrimidinium cation, dihydropyrimidinium cation, pyrazolium cation, pyrazolinium cation, and ammonium cation Is more preferable), and from the viewpoint of metal corrosion resistance and durability of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate, a pyridinium cation optionally having a substituent is further preferable. preferable.

A preferred specific example of the pyridinium cation which may have a substituent is represented by the following formula (II):

Is a pyridinium cation. In the above formula (II), R ^{1 to} R ⁶ each independently have a hydrogen atom, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent. Optionally alkynyl group, an aryl group optionally having a substituent, a heterocyclic group optionally having a substituent, a hydroxyl group, an ether group, a carboxyl group, a carbonyl group, or represents a halogen atom, The adjacent substituents may form a ring.

The alkyl group which may have a substituent is preferably an alkyl group having 1 to 30 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group and a decyl group. Group, dodecyl group, octadecyl group, isopropyl group, isobutyl group, sec-butyl group, t-butyl group, 1-ethylpentyl group, cyclopentyl group, cyclohexyl group, trifluoromethyl group, 2-ethylhexyl group, phenacyl group, 1 -Naphthoylmethyl group, 2-naphthoylmethyl group, 4-methylsulfanylphenacyl group, 4-phenylsulfanylphenacyl group, 4-dimethylaminophenacyl group, 4-cyanophenacyl group 4-methylphenacyl group, 2- It includes a methylphenacyl group, a 3-fluorophenacyl group, a 3-trifluoromethylphenacyl group, and a 3-nitrophenacyl group.

The alkenyl group which may have a substituent is preferably an alkenyl group having 2 to 10 carbon atoms, and specific examples thereof include, for example, a vinyl group, an allyl group and a styryl group. The alkynyl group which may have a substituent is preferably an alkynyl group having 2 to 10 carbon atoms, and specific examples thereof include, for example, an ethynyl group, a propynyl group and a propargyl group.

The aryl group which may have a substituent is preferably an aryl group having a carbon number of 6 to 30, and specific examples thereof include, for example, a phenyl group, a biphenyl group, a 1-naphthyl group, a 2-naphthyl group, and 9-anthryl. Group, 9-phenanthryl group, 1-pyrenyl group, 5-naphthacenyl group, 1-indenyl group, 2-azurenyl group, 9-fluorenyl group, terphenyl group, quarterphenyl group, o-, m-, and p-tolyl group Group, xylyl group, o-, m-, and p-cumenyl group, mesityl group, pentalenyl group, binaphthalenyl group, tarnaphthalenyl group, quarternaphthalenyl group, heptanenyl group, biphenylenyl group, indacenyl group, fluoranthenyl group, acenaphthylenyl group Group, aceanthrylenyl group, phenalenyl group, fluorenyl group, anthryl group, bianthracenyl group, taranthracenyl group, quarter anthracenyl group, anthraquinolyl group, phenanthryl group, triphenylenyl group, pyrenyl group, chrysenyl group, naphthalcenyl group, prey Adenyl group, picenyl group, perylenyl group, pentaphenyl group, pentacenyl group, tetraphenylenyl group, hexaphenyl group, hexacenyl group, rubicenyl group, coronenyl group, trinaphthylenyl group, heptaphenyl group, heptaenyl group, pyrantrenyl group, ovalenyl group including.

The heterocyclic group which may have a substituent is preferably an aromatic or aliphatic heterocyclic ring containing a nitrogen atom, an oxygen atom, a sulfur atom or a phosphorus atom, and specific examples thereof include a thienyl group and a benzo[ b] thienyl group, naphtho[2,3-b] thienyl group, thianthrenyl group, furyl group, pyranyl group, isobenzofuranyl group, chromeenyl group, xanthenyl group, phenoxathinyl group, 2H-pyrrolyl group, pyrrolyl group , Imidazolyl group, pyrazolyl group, pyridyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, indolizinyl group, isoindolyl group, 3H-indolyl group, indolyl group, 1H-indazolyl group, purinyl group, 4H-quinolidinyl group, isoquinolyl group, quinolyl Group, phthalazinyl group, naphthyridinyl group, quinoxanilyl group, quinazolinyl group, cinnolinyl group, pteridinyl group, 4aH-carbazolyl group, carbazolyl group, β-carbolinyl group, phenanthridinyl group, acridinyl group, perimidinyl group, phenanthrolinyl group , Phenazinyl group, phenalazinyl group, isothiazolyl group, phenothiazinyl group, isoxazolyl group, flazanyl group, phenoxazinyl group, isochromanyl group, chromanyl group, pyrrolidinyl group, pyrrolinyl group, imidazolidinyl group, imidazolinyl group, pyrazolidinyl group, pyrazolinyl group, pyrazolinyl group, pyrazolinyl group, pyrazolinyl group It includes a piperazinyl group, an indolinyl group, an isoindolinyl group, a quinuclidinyl group, a morpholinyl group, and a thioxanthryl group.

The alkyl group which may have a substituent, the alkenyl group which may have a substituent, the alkynyl group which may have a substituent, the aryl group which may have a substituent, and the substituent. Specific examples of the substituent capable of substituting the hydrogen atom of the heterocyclic group which may be present include, for example, halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom; methoxy group, ethoxy group, t-butoxy group and the like. Alkoxy group; phenoxy group, aryloxy group such as p-tolyloxy group, methoxycarbonyl group, butoxycarbonyl group, phenoxycarbonyl group, vinyloxycarbonyl group, aryloxycarbonyl group, and other alkoxycarbonyl group; acetoxy group, propionyloxy group An acyloxy group such as a benzoyloxy group; an acyl group such as an acetyl group, a benzoyl group, an isobutyryl group, an acryloyl group, a methacryloyl group, and a methoxalyl group; an alkylsulfanyl group such as a methylsulfanyl group and a t-butylsulfanyl group; a phenylsulfanyl group; Arylsulfanyl group such as p-tolylsulfanyl group; Alkylamino group such as methylamino group, cyclohexylamino group; Dialkylamino group such as dimethylamino group, diethylamino group, morpholino group, piperidino group; phenylamino group, p-tolylamino group And other arylamino groups; methyl groups, ethyl groups, t-butyl groups, dodecyl groups, and other alkyl groups; phenyl groups, p-tolyl groups, xylyl groups, cumenyl groups, naphthyl groups, anthryl groups, phenanthryl groups, and other aryl groups Hydroxyl group, carboxyl group, sulfonamide group, formyl group, mercapto group, sulfo group, mesyl group, p-toluenesulfonyl group, amino group, nitro group, nitroso group, cyano group, trifluoromethyl group, trichloromethyl group, It includes a trimethylsilyl group, a phosphinico group, a phosphono group, an alkylsulfonyl group, an arylsulfonyl group, a trialkylammonium group, a dimethylsulfoniumyl group, and a triphenylphenacylphosphoniumyl group.

The pyridinium cation represented by the above formula (II) is preferably an N-substituted pyridinium cation. In this case, R ¹ is preferably an alkyl group which may have a substituent, more preferably a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. The carbon number is preferably 1 to 16. R ^{2 to} R ⁶ are each independently preferably a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a hydroxyl group or a halogen atom, more preferably a hydrogen atom or a carbon atom. It is a linear alkyl group of the number 1 to 20.

Therefore, as a preferable example of the ionic compound (D) represented by the above formula (I), the following formula (III):

Is an ionic compound represented by. In the above formula (III), R ¹ is a linear, branched or cyclic alkyl group having ¹ to 16 carbon atoms, and R ^{2 to} R ⁶ are each independently a hydrogen atom or 1 to 20 carbon atoms. Is a linear alkyl group.

The content of the ionic compound (D) in the pressure-sensitive adhesive composition is preferably 0.1 to 10 parts by weight, more preferably 0.2, based on 100 parts by weight of the (meth)acrylic resin (A). To 8 parts by weight, more preferably 0.3 to 5 parts by weight, and particularly preferably 0.5 to 3 parts by weight. When the content of the ionic compound (D) is 0.1 parts by weight or more, it is advantageous for improving the antistatic performance, and when it is 10 parts by weight or less, the pressure-sensitive adhesive layer-attached optical film 1 and the optical laminate. Is advantageous in metal corrosion resistance and durability.

In the pressure-sensitive adhesive composition, an ionic compound (D) represented by the above formula (I) may be used in combination with other antistatic agents, but the pressure-sensitive adhesive layer-attached optical film 1 and the optical laminate are resistant to metal corrosion. From the viewpoint of properties and the like, the pressure-sensitive adhesive composition preferably contains only the ionic compound (D) represented by the above formula (I) as an antistatic agent.

[2-5] Other Components The pressure-sensitive adhesive composition is added with a solvent, a crosslinking catalyst, an ultraviolet absorber, a weather resistance stabilizer, a tackifier, a plasticizer, a softening agent, a dye, a pigment, an inorganic filler, light scattering fine particles and the like. One or two or more agents can be contained. In addition, it is also useful to mix an ultraviolet-curable compound in the pressure-sensitive adhesive composition, form the pressure-sensitive adhesive layer, and then irradiate the ultraviolet ray to cure the pressure-sensitive adhesive layer to obtain a harder pressure-sensitive adhesive layer. Examples of the crosslinking catalyst include amine compounds such as hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, polyamino resins and melamine resins.

The pressure-sensitive adhesive composition can contain an anticorrosive agent capable of enhancing the metal corrosion resistance of the pressure-sensitive adhesive layer-carrying optical film 1 and the optical laminate. Examples of rust preventives include benzotriazole-based compounds and other triazole-based compounds such as triazole-based compounds; benzothiazole-based compounds and other thiazole-based compounds and other thiazole-based compounds; benzylimidazole-based compounds and other imidazole-based compounds. 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; benzylmercapto-based compounds; di-sec-butyl sulfide; You can mention kid side.

However, according to the present invention, it is possible to obtain sufficient metal corrosion resistance without adding a rust preventive, and therefore it is preferable that the content of the rust preventive is as small as possible. In particular, the pressure-sensitive adhesive composition preferably contains substantially no triazole compound as a rust preventive, and more preferably contains substantially no rust preventive selected from the above compound group. Here, “not substantially containing” means that the content is 0.01 parts by weight or less based on 100 parts by weight of the (meth)acrylic resin (A).

[3] Metal Layer and Substrate The metal layer 30 contains, for example, aluminum, copper, silver, gold, iron, tin, zinc, nickel, molybdenum, chromium, tungsten, lead, and two or more metals selected from these. It can be a layer containing one or more selected from the group consisting of alloys, from the viewpoint of conductivity, preferably a layer containing a metal element selected from the group consisting of aluminum, copper, silver and gold, From the viewpoint of conductivity and cost, a layer containing an aluminum element is more preferable, and a layer containing an aluminum element as a main component is more preferable. The inclusion as the main component means that the metal component forming the metal layer 30 is 30% by weight or more, and further 50% by weight or more of the total metal components.

The metal layer 30 may be, for example, a metal oxide layer such as ITO, but the pressure-sensitive adhesive layer-attached optical film 1 according to the present invention is particularly excellent in corrosion resistance against a simple metal or an alloy, The layer 30 preferably contains a simple substance of the above metal element and/or an alloy containing two or more of the above metal elements. However, the optical layered body may have a transparent electrode layer made of a metal oxide such as ITO in addition to the metal layer 30.

The form (for example, thickness) of the metal layer 30 and the preparation method are not particularly limited, and the metal layer 30 may be a metal foil, and may be formed by a vacuum deposition method, a sputtering method, an ion plating method, an inkjet printing method, or a gravure printing method. However, a metal layer formed by a sputtering method, an inkjet printing method, or a gravure printing method is preferable, and a metal layer formed by sputtering is more preferable. In the metal layer formed by sputtering and the metal foil, the former tends to have poorer corrosion resistance, but the optical layered body according to the present invention is also good for the metal layer formed by sputtering. Has excellent metal corrosion resistance. 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. The thickness of the metal layer 30 is usually 0.01 μm or more. Further, when the metal layer 30 is a metal wiring layer, the line width of the metal wiring included in 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. The optical layered body according to the present invention exhibits excellent metal corrosion resistance even with respect to the thin metal layer 30 and the metal layer 30 formed of fine metal wiring. In particular, even when the metal wiring has, for example, a thickness of 3 μm or less and a line width of 10 μm or less, or a thickness of 3 μm or less and a line width of 10 μm or less and the metal wiring is formed by a sputtering method, the corrosion, especially the hole You can control your food.

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

The metal layer 30 may have a single-layer structure or a multi-layer structure having two layers or three or more layers. Examples of the multi-layered metal layer include a three-layered metal-containing layer (metal mesh or the like) represented by molybdenum/aluminum/molybdenum.

As shown in FIG. 1, a metal layer 30 such as a metal wiring layer is usually formed on a substrate 40, and in this case, the optical layered body according to the present invention includes this substrate 40. The metal layer 30 can be formed on the substrate 40 by, for example, sputtering. The substrate 40 may be a transparent substrate that constitutes a liquid crystal cell included in the touch input device. The substrate 40 is preferably a glass substrate. Examples of the material of the glass substrate include soda lime glass, low alkali glass, non-alkali glass and the like. 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, a glass substrate. Although it comes into direct contact with the adhesive layer 40, the pressure-sensitive adhesive layer 20 in the optical layered body according to the present invention is also excellent in adhesiveness to glass, so that the optical layered body and the liquid crystal display device including the optical layered body are It is also excellent in durability in such a case.

[4] Configuration and Manufacturing Method of Optical Layered Body In one embodiment, the optical layered body according to the present invention has an adhesive layer-attached optical film 1 and an adhesive layer 20 thereof as shown in FIGS. 4 and 5. And a metal layer 30 laminated on the side. In the optical laminates 5 and 6 shown in FIGS. 4 and 5, the pressure-sensitive adhesive layer-attached optical film 1 is laminated on the metal layer 30 so that the pressure-sensitive adhesive layer 20 is in direct contact with the metal layer 30. According to the present invention, the corrosion of the metal layer 30 can be effectively suppressed even in the optical layered body in which the pressure-sensitive adhesive layer 20 directly contacts the metal layer 30 as described above.

FIG. 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, the optical layered body according to the present invention has the pressure-sensitive adhesive layer 20 of the pressure-sensitive adhesive layer-attached optical film 1 on the metal layer 30 via the resin layer 50, as in the optical layered body 7 shown in FIG. It is stacked. The adhesive layer 20 is in direct contact with the resin layer 50. Also in such an optical layered body 7, corrosion of the metal layer 30 can be effectively suppressed. The resin layer 50 arranged between the adhesive layer 20 and the metal layer 30 may be, for example, a cured product layer of a curable resin. As the curable resin capable of forming the resin layer 50, a known curable resin can be used, and examples thereof include those described in JP-A 2009-217037.

As described above, the metal layer 30 may be a metal wiring layer. FIG. 7 shows an example in which the metal layer 30 is a metal wiring layer. The resin layer 50 may be omitted in the optical laminate shown in FIG. 7.

The optical layered body includes, for example, the pressure-sensitive adhesive layer-attached optical film 1 including the optical film 10 on the metal layer 30 formed on the substrate 40 and the pressure-sensitive adhesive layer 20 laminated on at least one surface thereof. Can be prepared by laminating the adhesive via the adhesive layer 20.

As described above, the pressure-sensitive adhesive layer-attached optical film 1 includes the optical film 10 and the pressure-sensitive adhesive layer 20 laminated on at least one surface thereof (FIG. 1 ). The pressure-sensitive adhesive layer 20 may be laminated on both surfaces of the optical film 10. Usually, the pressure-sensitive adhesive layer 20 is directly laminated on the surface of the optical film 10. When the pressure-sensitive adhesive layer 20 is provided 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, for example, plasma treatment, Corona treatment or the like is preferable, and corona treatment is more preferable.

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 preferably on the polarizer surface, that is, on the surface of the polarizer 2 opposite to the first resin film 3. Are stacked directly. 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 one of the outer surfaces of the first and second resin films 3 and 4, or both outer surfaces. It may be laminated.

Although an antistatic layer may be separately provided between the optical film 10 and the pressure-sensitive adhesive layer 20, the pressure-sensitive adhesive layer 20 of the present invention can impart excellent antistatic properties by the pressure-sensitive adhesive layer alone. From the viewpoint of thinning the laminated body and simplifying the laminated body manufacturing process, it is preferable not to have an antistatic layer between the optical film 10 and the pressure-sensitive adhesive layer 20.

The pressure-sensitive adhesive layer-attached optical film 1 may include a separate film (release film) laminated on the outer surface of the pressure-sensitive adhesive layer 20. This separate film is usually peeled off when the pressure-sensitive adhesive layer 20 is used (for example, when laminated on the metal layer 30). The separate film is, for example, a film made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarate, etc., on which the pressure-sensitive adhesive layer 20 is formed, a release treatment such as silicone treatment is performed. You can

The pressure-sensitive adhesive layer-attached optical film 1 is obtained by dissolving or dispersing each component constituting the pressure-sensitive adhesive composition in a solvent to obtain a solvent-containing pressure-sensitive adhesive composition, and then coating and drying the same on the surface of the optical film 10. Can be obtained by forming the pressure-sensitive adhesive layer 20. In the pressure-sensitive adhesive layer-attached optical film 1, the pressure-sensitive adhesive layer 20 is formed on the release-treated surface of the separate film in the same manner as above, and the pressure-sensitive adhesive layer 20 is laminated (transferred) on the surface of the optical film 10. You can also get

An optical laminate can be obtained by laminating the pressure-sensitive adhesive layer-attached optical film 1 on the metal layer 30 (or the resin layer) via the pressure-sensitive adhesive layer 20. After the pressure-sensitive adhesive layer-attached optical film 1 and the metal layer 30 are adhered to each other to produce an optical laminate, if there is any problem, the pressure-sensitive adhesive layer-attached optical film 1 is peeled off from the metal layer 30 and separated. There is a case where a so-called rework operation of reattaching the pressure-sensitive adhesive layer-attached optical film 1 to the metal layer 30 is required. The optical layered body according to the present invention is excellent in reworkability because clouding, adhesive residue, and the like hardly occur on the surface of the metal layer 30 after the pressure-sensitive adhesive layer-attached optical film 1 is peeled from the metal layer 30. According to the optical layered body of the present invention, good reworkability can be exhibited even when the surface on which the pressure-sensitive adhesive layer 20 is bonded is not the metal layer 30 but the glass substrate or the ITO layer.

<Liquid crystal display>
A liquid crystal display device according to the present invention includes the optical layered body according to the present invention. The liquid crystal display device according to the present invention can suppress the 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. The 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, an in-cell type, etc., and the operation method of the touch panel is a resistance film method or an electrostatic capacity method (surface type electrostatic capacity method, projection type). Any conventionally known method such as a capacitance method) may be used. The optical laminate according to the present invention may be arranged on the viewing side of the touch input element (liquid crystal cell), on the backlight side, or on both sides. The driving method of the liquid crystal cell may be any conventionally known method such as TN method, VA method, IPS method, multi-domain method, OCB method. In the liquid crystal display device according to the present invention, the substrate 40 included in the optical laminate may be a substrate (typically a glass substrate) included in the liquid crystal cell.

Hereinafter, the present invention will be described more specifically by showing Examples and Comparative Examples, but the present invention is not limited to these Examples. In the following, the amounts used and parts and percentages representing the contents are on a weight basis unless otherwise specified.

<Production Example 1: Production of (meth)acrylic resin (A-1) for adhesive layer>
A reaction vessel equipped with a cooling pipe, a nitrogen introducing pipe, a thermometer and a stirrer was mixed with a monomer having the composition shown in Table 1 (the numerical values in Table 1 are parts by weight) and 81.8 parts of ethyl acetate. The resulting solution was charged. After replacing the air in the reaction vessel with nitrogen gas, the internal temperature was set to 60°C. Then, a solution of 0.12 parts of azobisisobutyronitrile dissolved in 10 parts of ethyl acetate was added. After maintaining 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 became about 35% while maintaining the internal temperature at 54 to 56°C. I added it. After maintaining the internal temperature at 54 to 56° C. for 12 hours from the start of addition of ethyl acetate, ethyl acetate was added to adjust the concentration of the polymer to 20%, and the (meth)acrylic resin ( An ethyl acetate solution of A-1) was obtained. The weight average molecular weight Mw of the (meth)acrylic resin (A-1) was 1.39 million, and the ratio Mw/Mn of the weight average molecular weight Mw to the number average molecular weight Mn was 5.32. In the emission curve of gel permeation chromatography (GPC), the component with Mw of 139,000 showed a single peak, and no other peak was observed in the range of Mw of 1,000 to 2.5 million.

<Production Example 2: Production of (meth)acrylic resin (A-2) for adhesive layer>
An ethyl acetate solution of (meth)acrylic resin (A-2) was obtained in the same manner as in Production Example 1 except that the composition of the monomers was as shown in Table 1 (resin concentration: 20% ). The (meth)acrylic resin (A-2) had a weight average molecular weight Mw of 14.1 million and Mw/Mn of 4.71. In the emission curve of GPC, the component with Mw of 1.41 million showed a single peak, and no other peak was observed in the range of Mw of 1,000 to 2.5 million.

In the above production example, the weight average molecular weight Mw and the number average molecular weight Mn were 4 columns of "TSKgel XL" manufactured by Tosoh Corp. and "Shodex GPC KF-" manufactured by Showa Denko K.K. 802” is connected in series with a total of 5 pieces, and tetrahydrofuran is used as an eluent. Sample concentration is 5 mg/mL, sample introduction amount is 100 μL, temperature is 40° C., and flow rate is 1 mL/min. It was measured by. The conditions for obtaining the emission curve of GPC were also the same.

The glass transition temperature Tg was measured by using a differential scanning calorimeter (DSC) “EXSTAR DSC6000” manufactured by SII Nano Technology Co., Ltd. under a nitrogen atmosphere in a measurement temperature range of −80 to 50° C. and a heating rate of 10° C./min. It was measured under the conditions.

The composition of the monomer in each production example (the numerical values in Table 1 are parts by weight), and the number of peaks in the range of Mw 1000 to 2.5 million on the emission curve of GPC (indicated as "GPC peak number" in Table 1). Are summarized in Table 1.

Abbreviations in the column of "monomer composition" in 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 In the ethyl acetate solution (resin concentration: 20%) of the (meth)acrylic resin obtained in the above Production Example, the solid content of 100 parts of the solution is shown in Table 2. The isocyanate crosslinking agent (B), the silane compound (C), and the ionic compound (D) were mixed in the amounts (parts by weight) shown in Table 2, and ethyl acetate was added so that the solid content concentration became 14%. Then, an adhesive composition was obtained. The blending amount of each blending component shown in Table 2 is the number of parts by weight as an active ingredient contained therein when the used product contains a solvent and the like.

Details of each compounding component represented by abbreviations in Table 2 are as follows.
(Isocyanate crosslinking agent)
B-1: A solution of trimethylolpropane adduct of xylylene diisocyanate in ethyl acetate (solid content concentration: 75%), trade name “Takenate D-110N” obtained from Mitsui Chemicals, Inc.

(Silane compound)
C-1:3-glycidoxypropyltrimethoxysilane, trade name "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(Ionic compound)
D-1: The following formula:

An ionic compound represented by
D-2: The following formula:

An ionic compound represented by
D-3: N-octyl-4-methylpyridinium hexafluorophosphate.

(2) Preparation of pressure-sensitive adhesive layer Each of the pressure-sensitive adhesive compositions prepared in (1) above is a separate film made of a polyethylene terephthalate film that has been subjected to a release treatment [trade name "PLR-382051 obtained from Lintec Co., Ltd.]. ]] was applied to the release-treated surface using an applicator so that the thickness after drying was 20 μm, and dried at 100° C. for 1 minute to prepare a pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet).

(3) Preparation of pressure-sensitive adhesive layer-attached optical film (P-1) 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 “Kuraray vinylon VF manufactured by Kuraray Co., Ltd.] -PE#6000"] was immersed in pure water at 37°C, and then an aqueous solution containing iodine and potassium iodide (iodine/potassium iodide/water (weight ratio) = 0.04/1.5/100) It was immersed in 30° C. Then, it was immersed at 56.5° C. in an aqueous solution containing potassium iodide and boric acid (potassium iodide/boric acid/water (weight ratio)=12/3.6/100). The film was washed with pure water at 10° C. and then 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.] consisting of a 25 μm-thick triacetyl cellulose film was provided on one surface of the obtained polarizer through an adhesive composed of an aqueous solution of polyvinyl alcohol resin. Pasted together. Next, on the surface of the above-mentioned polarizer opposite to the triacetyl cellulose film, a zero retardation film [trade name "ZEONOR" manufactured by Nippon Zeon Co., Ltd.] made of a cyclic polyolefin resin having a thickness of 23 μm was used. A laminated polarizing plate was prepared with an adhesive made of an aqueous solution of resin. Then, the surface of the zero retardation film opposite to the surface in contact with the polarizer was subjected to corona discharge treatment for improving the adhesion, and then the surface opposite to the separate film of the pressure-sensitive adhesive layer prepared in (2) above. After sticking the side surface (adhesive layer surface) with a laminator, it was cured for 7 days under the 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) Preparation of optical film with pressure-sensitive adhesive layer (P-2) 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 [Kuraray's trade name “Kuraray Vinylon VF” -PE#3000"] was immersed in pure water at 37°C, and then an aqueous solution containing iodine and potassium iodide (iodine/potassium iodide/water (weight ratio) = 0.04/1.5/100) It was immersed in 30° C. Then, it was immersed at 56.5° C. in an aqueous solution containing potassium iodide and boric acid (potassium iodide/boric acid/water (weight ratio)=12/3.6/100). The film was washed with pure water at 10° C. and then dried at 85° C. to obtain a polarizer having a thickness of about 12 μm in which polyvinyl alcohol was adsorbed and oriented with iodine. 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.] consisting of a 25 μm-thick triacetyl cellulose film was provided on one surface of the obtained polarizer through an adhesive composed of an aqueous solution of polyvinyl alcohol resin. Then, they were attached to each other to prepare a polarizing plate. Next, the surface of the pressure-sensitive adhesive layer prepared in the above (2) opposite to the separate film (pressure-sensitive adhesive layer surface) was bonded to the surface opposite to the surface of the polarizer protective film bonded by a laminator. Then, it was aged for 7 days under the conditions of a temperature of 23° C. and a relative humidity of 65% to obtain an adhesive layer-attached optical film (P-2).

(5) Evaluation of metal corrosion resistance of optical film with pressure-sensitive adhesive layer The optical film with pressure-sensitive adhesive layer (P-1) produced in the above (3) was cut into a test piece having a size of 20 mm×50 mm to form a metal layer. It was adhered to the metal layer side of the attached glass substrate via an adhesive layer. As the glass substrate with a metal layer, a glass substrate (manufactured by Geomatec Co., Ltd.) in which a metal aluminum layer having a thickness of about 500 nm was laminated on a non-alkali glass surface by sputtering was used. The obtained optical layered body was stored in an oven at a temperature of 60° C. and a relative humidity of 90% for 500 hours, and then the state of the metal layer of the portion to which the optical film with the pressure-sensitive adhesive layer was attached was observed from the back surface of the glass substrate. The sample was observed from the surface of the polarizing plate through a magnifying glass (loupe) by applying a mark, and pitting corrosion (generation of holes 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 3.

4: The number of pitting corrosion generated on the surface of the metal layer is 2 or less,
3: The number of pitting corrosion generated on the surface of the metal layer is 3 to 5,
2: The number of pitting corrosion generated on the surface of the metal layer is 6 or more,
1: Many pitting corrosions were generated on the entire surface of the metal layer, and white turbidity was also generated.

(6) Durability evaluation of pressure-sensitive adhesive layer-attached optical film The pressure-sensitive adhesive layer-attached optical film (P-1) produced in the above (3) was measured in 200 mm×150 mm so that the stretching axis direction of the polarizing plate was the long side. It was cut into a size, the separate film was peeled off, and the exposed pressure-sensitive adhesive layer surface was bonded to a glass substrate. The test piece to which the glass substrate was attached (optical film with pressure-sensitive adhesive layer attached to the glass substrate) was placed in an autoclave at a temperature of 50° C. and a pressure of 5 kg/cm ² (490.3 kPa) for 20 minutes. Pressurized. As the glass substrate, non-alkali glass trade name “Eagle XG” manufactured by Corning was used. The following three types of durability tests were performed on the obtained optical layered body.

[Durability test]
・Heat resistance test of keeping for 750 hours under the dry condition of temperature 85℃,
・Humidity and heat resistance test for holding for 750 hours in an environment of temperature 60°C and relative humidity 90%,
A heat shock resistance (HS) test in which an operation of holding the material under a drying condition of a temperature of 85° C. for 30 minutes and then for a holding time of 30 minutes under a drying condition of a temperature of −40° C. is repeated for 400 cycles.

The optical laminate after each test was visually observed, and the presence or absence of appearance change such as floating, 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 floating, peeling, foaming, etc.
3: Almost no change in appearance such as floating, peeling, foaming,
2: The appearance changes such as floating, peeling and foaming are slightly noticeable,
1: Appearance changes such as floating, peeling and foaming are noticeable.

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

4: No fogging on the surface of the glass substrate,
3: Almost no cloudiness was observed on the surface of the glass substrate,
2: Fogging or the like is observed on the surface of the glass substrate,
1: Remaining adhesive layer is observed on the surface of the glass substrate.

(8) Evaluation of color loss property of optical film with pressure-sensitive adhesive layer The optical film with pressure-sensitive adhesive layer (P-2) produced in (4) above was cut into a size of 30 mm×30 mm to separate the separate film and exposed. The pressure-sensitive adhesive layer surface was attached to a glass substrate. As the glass substrate, non-alkali glass trade name “Eagle XG” manufactured by Corning was used. About the obtained optical laminate, the MD transmittance and the TD transmittance in the wavelength range of 380 to 780 nm were measured using a spectrophotometer with an integrating sphere [product name "V7100" manufactured by JASCO Corporation). single transmittance at a wavelength, calculate the degree of polarization, further JIS Z 8701: 1999 visibility correction by a two-degree visual field (C light source) "color display method -XYZ color system and X ₁₀ Y ₁₀ Z ₁₀ color system" Then, the luminosity-corrected single transmittance (Ty) and the luminosity-corrected polarization degree (Py) before the durability test were determined. The optical layered body was set in a spectrophotometer with an integrating sphere such that the triacetyl cellulose film side of the polarizing plate was the detector side and light was incident from the glass substrate side.

The single transmittance and the polarization degree are calculated by the following formulas:
Single transmittance (λ)=0.5×(Tp(λ)+Tc(λ))
Polarization degree (λ)=100×(Tp(λ)−Tc(λ))/(Tp(λ)+Tc(λ))
Is defined by Tp(λ) is the transmittance (%) of the optical laminate measured by the relationship between the linearly polarized light having the incident wavelength λ(nm) and the parallel Nicol, and Tc(λ) is the incident wavelength λ(nm). It is the transmittance (%) of the optical laminate measured by the relationship between linearly polarized light and crossed Nicols.

Then, this optical layered body is placed in a heat and humidity environment at a temperature of 80° C. and a relative humidity of 90% for 24 hours, further placed in an environment of a temperature of 23° C. and a relative humidity of 60% for 24 hours, and then subjected to the same method as before the durability test. The Ty and Py after the durability test were determined by. Then, Py and Ty before the test were respectively subtracted from Py and Ty after the test to calculate the change amounts before and after the durability test, and the polarization degree change amount (ΔPy) and the single-piece transmittance change amount (ΔTy) were obtained. Table 3 shows ΔPy.

<Production Example 3: Production of (meth)acrylic resin (A-1) for adhesive layer>
A monomer having the composition shown in Table 4 (the numerical values in Table 4 are parts by weight) was mixed with 81.8 parts of ethyl acetate in a reaction vessel equipped with a cooling tube, a nitrogen introducing tube, a thermometer and a stirrer. The resulting solution was charged. After replacing the air in the reaction vessel with nitrogen gas, the internal temperature was set to 60°C. Then, a solution of 0.12 parts of azobisisobutyronitrile dissolved in 10 parts of ethyl acetate was added. After maintaining 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 became about 35% while maintaining the internal temperature at 54 to 56°C. I added it. After maintaining the internal temperature at 54 to 56° C. for 12 hours from the start of addition of ethyl acetate, ethyl acetate was added to adjust the concentration of the polymer to 20%, and the (meth)acrylic resin ( An ethyl acetate solution of A-1) was obtained. The weight average molecular weight Mw of the (meth)acrylic resin (A-1) was 1.39 million, and the ratio Mw/Mn of the weight average molecular weight Mw to the number average molecular weight Mn was 5.32. In the emission curve of gel permeation chromatography (GPC), the component with Mw of 139,000 showed a single peak, and no other peak was observed in the range of Mw of 1,000 to 2.5 million.

In the above production example, the weight average molecular weight Mw and the number average molecular weight Mn were 4 columns of "TSKgel XL" manufactured by Tosoh Corp. and "Shodex GPC KF-" manufactured by Showa Denko K.K. 802” is connected in series with a total of 5 pieces, and tetrahydrofuran is used as an eluent. Sample concentration is 5 mg/mL, sample introduction amount is 100 μL, temperature is 40° C., and flow rate is 1 mL/min. It was measured by. The conditions for obtaining the emission curve of GPC were also the same.

The glass transition temperature Tg was measured by using a differential scanning calorimeter (DSC) “EXSTAR DSC6000” manufactured by SII Nano Technology Co., Ltd. under a nitrogen atmosphere in a measurement temperature range of −80 to 50° C. and a heating rate of 10° C./min. It was measured under the conditions.

Composition of monomer in Production Example 3 (numerical values in Table 4 are parts by weight), and number of peaks in the range of Mw 1000 to 2.5 million on the emission curve of GPC (indicated as "GPC peak number" in Table 4) Are summarized in Table 4.

Abbreviations in the column of "monomer composition" 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 Example 2>
(1) Preparation of pressure-sensitive adhesive composition Table 5 shows the results in the ethyl acetate solution (resin concentration: 20%) of the (meth)acrylic resin obtained in the above Production Example, relative to 100 parts of solid content of the solution. The isocyanate cross-linking agent (B), the silane compound (C), and the ionic compound (D) were mixed in the amounts (parts by weight) shown in Table 5, and ethyl acetate was added so that the solid content concentration was 14%. Then, an adhesive composition was obtained. The blending amount of each blending component shown in Table 5 is the number of parts by weight as an active ingredient contained therein when the used product contains a solvent and the like.

Details of each compounding component represented by abbreviations in Table 5 are as follows.
(Isocyanate crosslinking agent)
B-1: A solution of trimethylolpropane adduct of xylylene diisocyanate in ethyl acetate (solid content concentration: 75%), trade name “Takenate D-110N” obtained from Mitsui Chemicals, Inc.

(Silane compound)
C-1:3-glycidoxypropyltrimethoxysilane, trade name "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(Ionic compound)
D-2: The following formula:

An ionic compound represented by
D-3: N-octyl-4-methylpyridinium hexafluorophosphate.

(2) Preparation of pressure-sensitive adhesive layer Each of the pressure-sensitive adhesive compositions prepared in (1) above is a separate film made of a polyethylene terephthalate film that has been subjected to a release treatment [trade name "PLR-382051 obtained from Lintec Co., Ltd.]. ]] was applied to the release-treated surface using an applicator so that the thickness after drying was 20 μm, and dried at 100° C. for 1 minute to prepare a pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet).

(3) Preparation of pressure-sensitive adhesive layer-attached optical film (P-1) 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 “Kuraray vinylon VF manufactured by Kuraray Co., Ltd.] -PE#6000"] was immersed in pure water at 37°C, and then an aqueous solution containing iodine and potassium iodide (iodine/potassium iodide/water (weight ratio) = 0.04/1.5/100) It was immersed in 30° C. Then, it was immersed at 56.5° C. in an aqueous solution containing potassium iodide and boric acid (potassium iodide/boric acid/water (weight ratio)=12/3.6/100). The film was washed with pure water at 10° C. and then 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.] consisting of a 25 μm-thick triacetyl cellulose film was provided on one surface of the obtained polarizer through an adhesive composed of an aqueous solution of polyvinyl alcohol resin. Pasted together. Next, on the surface of the above-mentioned polarizer opposite to the triacetyl cellulose film, a zero retardation film [trade name "ZEONOR" manufactured by Nippon Zeon Co., Ltd.] made of a cyclic polyolefin resin having a thickness of 23 μm was used. A laminated polarizing plate was prepared with an adhesive made of an aqueous solution of resin. Then, the surface of the zero retardation film opposite to the surface in contact with the polarizer was subjected to corona discharge treatment for improving the adhesion, and then the surface opposite to the separate film of the pressure-sensitive adhesive layer prepared in (2) above. After sticking the side surface (adhesive layer surface) with a laminator, it was cured for 7 days under the 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) Evaluation of metal corrosion resistance of optical film with pressure-sensitive adhesive layer (4-1) In the case of Example 4 The optical film with pressure-sensitive adhesive layer (P-1) produced in (3) above was measured in a size of 20 mm×50 mm. The test piece was cut into pieces and attached to the metal layer side of the glass substrate with a metal layer via the adhesive layer. As the glass substrate with a metal layer, a glass substrate (manufactured by Geomatec Co., Ltd.) in which a metal copper layer having a thickness of about 500 nm was laminated by sputtering on a non-alkali glass surface was used. The obtained optical layered body was stored in an oven at a temperature of 60° C. and a relative humidity of 90% for 120 hours, and then the state of the metal layer at the portion where the optical film with an adhesive layer was attached was observed from the back surface of the glass substrate. Then, the surface of the polarizing plate was observed with a magnifying glass, and pitting corrosion (generation of holes 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.

(4-2) In the case of Example 5 and Comparative Example 2 The pressure-sensitive adhesive layer-carrying optical film (P-1) produced in (3) above was cut into a test piece having a size of 20 mm×50 mm, and a metal layer was attached. The glass substrate was attached to the metal layer side via an adhesive layer. As the glass substrate with a metal layer, a glass substrate (manufactured by Geomatec Co., Ltd.) in which a silver alloy (alloy containing APC as a main component of silver and containing APC) having a thickness of about 500 nm is laminated on a non-alkali glass surface by sputtering is used. used. The obtained optical layered body was stored in an oven at a temperature of 60° C. and a relative humidity of 90% for 500 hours, and then the state of the metal layer of the portion to which the optical film with the pressure-sensitive adhesive layer was attached was observed from the back surface of the glass substrate. Then, the surface of the polarizing plate was observed with a magnifying glass, and pitting corrosion (generation of holes 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 pitting corrosion generated on the surface of the metal layer is 2 or less,
3: The number of pitting corrosion generated on the surface of the metal layer is 3 to 5,
2: The number of pitting corrosion generated on the surface of the metal layer is 6 or more,
1: Many pitting corrosions were generated on the entire surface of the metal layer, and white turbidity was also generated.

1 Optical Film with Adhesive Layer, 2 Polarizer, 3rd Resin Film, 4th Resin Film, 5, 6, 7 Optical Laminate, 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 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),
The ionic compound (D) has the following formula (I):

(In the formula, A ⁺ represents an organic or inorganic cation.)
An optical laminate which is an ionic compound represented by. 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 alloys containing two or more metals selected from these. The optical laminate according to claim 1, which comprises: The optical layered body according to claim 1, wherein the metal layer contains an aluminum element. The optical layered body according to any one of claims 1 to 3, wherein the metal layer is a layer formed by sputtering. The optical layered body according to any one of claims 1 to 4, wherein the metal layer has a thickness of 3 µm or less. The optical layered body according to any one of claims 1 to 5, wherein the metal layer is a metal wiring layer. The optical laminated body according to claim 6, wherein the metal wiring included in the metal wiring layer has a line width of 10 μm or less. The optical layered body according to any one of claims 1 to 7, wherein A ^{+ in the} formula (I) is an organic cation. The optical layered body according to any one of claims 1 to 7, wherein A ⁺ of the formula (I) is a nitrogen atom-containing organic cation. A ⁺ of the formula (I) is the following formula (II):

(In the formula, R ^{1 to} R ⁶ are each independently a hydrogen atom, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent which may have a substituent. A good alkynyl group, an aryl group which may have a substituent, a heterocyclic group which may have a substituent, a hydroxyl group, an ether group, a carboxyl group, a carbonyl group, or a halogen atom, which are adjacent substituents The groups may form a ring.)
The optical layered body according to any one of claims 1 to 7, which is a pyridinium cation represented by. The (meth)acrylic resin (A) contains a structural unit derived from an alkyl(meth)acrylate in which an alkyl group has 1 to 14 carbon atoms, and a structural unit derived from a monomer having a hydroxyl group. Item 11. The optical laminate according to any one of items 1 to 10. The optical laminate according to any one of claims 1 to 11, wherein the (meth)acrylic resin (A) does not substantially contain a structural unit derived from a monomer having a carboxyl group. The (meth)acrylic resin (A) is a structural unit derived from an alkyl acrylate (a1) in which the homopolymer has a glass transition temperature of less than 0° C., and an alkyl acrylate (in which the homopolymer has a glass transition temperature of 0° C. or higher ( The optical layered body according to any one of claims 1 to 12, which contains a structural unit derived from a2). The content of the isocyanate-based crosslinking agent (B) in the pressure-sensitive adhesive composition is 0.08 to 2.5 parts by weight with respect to 100 parts by weight of the (meth)acrylic resin (A). ~ The optical layered body according to any one of claims 13 to 14. Content of the said ionic compound (D) in the said adhesive composition is 0.2-8 weight part with respect to 100 weight part of the (meth)acrylic-type resin (A), Claims 1-claim. 15. The optical layered body according to any one of 14 above. The adhesive composition is a triazole compound, a thiazole compound, an imidazole compound, an imidazoline compound, a quinoline compound, a pyridine compound, a pyrimidine compound, an indole compound, an amine compound, a urea compound, sodium benzoate, The optical element according to any one of claims 1 to 15, which is substantially free of a rust inhibitor selected from the group consisting of benzylmercapto compounds, di-sec-butyl sulfide, and diphenyl sulfoxide. Laminate. The optical laminate according to any one of claims 1 to 16, wherein the (meth)acrylic resin (A) does not substantially include a structural unit derived from a monomer having a carboxyl group. The optical layered body according to any one of claims 1 to 17, wherein the silane compound (C) is a silane compound other than a silane compound having a mercapto group as a functional group that reacts with an organic material. The silane compound (C) is vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidyl. Sidoxypropylmethyldimethoxysilane, 3-glycidoxypropylethoxydimethylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, and 3 -The optical laminate according to any one of claims 1 to 18, which is one kind or two or more kinds selected from the group consisting of methacryloyloxypropyltrimethoxysilane. A liquid crystal display device comprising the optical layered body according to any one of claims 1 to 19 . Contains a (meth)acrylic resin (A), an isocyanate crosslinking agent (B), a silane compound (C), and an ionic compound (D),
The ionic compound (D) has the following formula (I):

(In the formula, A ⁺ represents an organic or inorganic cation.)
Is an ionic compound represented by
A pressure-sensitive adhesive composition used for forming a pressure-sensitive adhesive layer laminated on a metal layer. An optical film, comprising an adhesive layer laminated on at least one surface of the optical film, an optical film with an adhesive layer for laminating on a metal layer via the adhesive layer,
The adhesive layer is
Contains a (meth)acrylic resin (A), an isocyanate crosslinking agent (B), a silane compound (C), and an ionic compound (D),
The ionic compound (D) has the following formula (I):

(In the formula, A ⁺ represents an organic or inorganic cation.)
Is an ionic compound represented by
An optical film with a pressure-sensitive adhesive layer, which is formed from a pressure-sensitive adhesive composition.

Images