KR20220024417A - Pressure-sensitive adhesive composition, pressure-sensitive adhesive layer, pressure-sensitive adhesive sheet and optical laminate - Google Patents

Abstract

The present invention provides a pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer capable of well peeling a release film formed on both surfaces, a pressure-sensitive adhesive layer, a pressure-sensitive adhesive sheet, and an optical laminate. The pressure-sensitive adhesive composition includes a resin, a crosslinking agent, and a silane compound. The silane compound includes a Si-O-Si bond in a main chain, both ends of the main chain of the silane compound have functional groups other than hydrolysable groups, and the side chain of the silane compound has a functional group other than a carboxyl group. It is preferable that the said silane compound is a leveling agent.

Description

Pressure-sensitive adhesive composition, pressure-sensitive adhesive layer, pressure-sensitive adhesive sheet and optical laminate

The present invention relates to an optical laminate comprising a pressure-sensitive adhesive composition, a pressure-sensitive adhesive layer using the same, an pressure-sensitive adhesive sheet, and an pressure-sensitive adhesive layer.

Generally, in image display apparatuses, such as a liquid crystal display device and an organic electroluminescent display, optical members, such as a polarizing plate and retardation film, are provided with the structure bonded to the display unit containing a display element etc. via an adhesive layer. In such an image display device, for example, from a pressure-sensitive adhesive sheet having a release film formed so as to be peelable on both surfaces of the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer exposed by peeling the one release film is bonded to the optical member, and then, the other side is peeled off It can manufacture by bonding the adhesive layer exposed by peeling a film to a display unit.

Patent Document 1: Japanese Patent Laid-Open No. 2016-194071

When the release film formed on both surfaces of the adhesive layer of an adhesive sheet has the same mold release process layer, the peeling force at the side of the mold release process layer of an adhesive layer and a release film becomes the same. For this reason, a certain part of an adhesive layer peels with one peeling film, the other part of an adhesive layer peels with the other peeling film, There may be a problem that an adhesive layer separates partially. . This problem is sometimes referred to as partial non-peelability, but when partial non-peelability occurs, it becomes difficult to form a uniform pressure-sensitive adhesive layer between the optical member and the display unit, and good adhesion between the optical member and the display unit is ensured. it gets difficult

An object of this invention is to provide the adhesive composition for forming the adhesive layer which can peel favorably the peeling film formed on both surfaces, an adhesive layer, an adhesive sheet, and an optical laminated body.

The present invention provides the following pressure-sensitive adhesive composition, pressure-sensitive adhesive layer, pressure-sensitive adhesive sheet, and optical laminate.

[1] a resin, a crosslinking agent, and a silane compound,

The silane compound comprises a Si-O-Si bond in the main chain,

Both ends of the main chain of the silane compound have a functional group other than a hydrolyzable group,

The side chain of the silane compound is a pressure-sensitive adhesive composition having a functional group other than a carboxyl group.

[2] The pressure-sensitive adhesive composition according to [1], wherein the silane compound is a leveling agent.

[3] The pressure-sensitive adhesive composition according to [1] or [2], wherein both terminals of the main chain of the silane compound are each independently an alkyl group, a halogenated alkyl group, a phenyl group or an aralkyl group.

[4] The pressure-sensitive adhesive composition according to any one of [1] to [3], wherein both terminals of the main chain of the silane compound are methyl groups.

[5] The pressure-sensitive adhesive composition according to any one of [1] to [4], wherein the side chains of the silane compound are each independently an alkyl group or an aralkyl group.

[6] The pressure-sensitive adhesive composition according to any one of [1] to [5], wherein the silane compound has a viscosity of 300 mPa·s or more at a temperature of 25°C.

[7] The pressure-sensitive adhesive composition according to any one of [1] to [6], further comprising a silane coupling agent.

[8] The silane coupling agent contains a siloxane compound including a Si-O-Si bond in the main chain,

The pressure-sensitive adhesive composition according to [7], wherein the siloxane compound has a hydrolyzable group in its main chain.

[9] The pressure-sensitive adhesive composition according to any one of [1] to [8], wherein the resin contains a (meth)acrylic resin.

[10] A pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition according to any one of [1] to [9].

[11] A pressure-sensitive adhesive sheet in which a release film having the same release treatment layer is formed on both surfaces of the pressure-sensitive adhesive layer according to [10],

Let the peeling force between the one side of the said adhesive layer and the said release-treated layer side of the said peeling film be a 1st peeling force, and the said release of the said peeling film from the other side of the said adhesive layer on the opposite side to the said one side. When the peeling force between the treatment layers is the second peeling force, the first peeling force and the second peeling force are different from each other.

[12] An optical laminate comprising an optical layer and a pressure-sensitive adhesive layer,

The pressure-sensitive adhesive layer is the pressure-sensitive adhesive layer according to [10], the optical laminate.

[13] The optical laminate according to [12], wherein the optical layer includes a polarizing plate.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition for forming the adhesive layer which can peel favorably the peeling film formed on both surfaces, an adhesive layer, an adhesive sheet, and an optical laminated body can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS 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 optical layer which the optical laminated body which concerns on this invention has.
It is a schematic sectional drawing which shows another example of the optical layer which the optical laminated body which concerns on this invention has.
It is a schematic sectional drawing which shows another example of the layer structure of the optical laminated body which concerns on this invention.
It is a schematic sectional drawing which shows another example of the laminated constitution of the optical laminated body which concerns on this invention.
It is a schematic sectional drawing which shows another example of the layer structure of the optical laminated body which concerns on this invention.
It is a schematic sectional drawing which shows another example of the laminated constitution of the optical laminated body which concerns on this invention.
It is a schematic sectional drawing which shows another example of the laminated constitution of the optical laminated body which concerns on this invention.

<Adhesive composition>

The adhesive composition which concerns on this invention contains resin, a crosslinking agent, and a silane compound. In addition to resin, a crosslinking agent, and a silane compound, the adhesive composition may contain the silane coupling agent. Hereinafter, the resin is referred to as "resin (A)", the crosslinking agent is referred to as "crosslinking agent (B)", the silane compound is referred to as "silane compound (C)", and the silane coupling agent is referred to as "silane coupling agent (D)" there is

Examples of the pressure-sensitive adhesive composition include a (meth)acrylic pressure-sensitive adhesive composition, a urethane pressure-sensitive adhesive composition, a silicone pressure-sensitive adhesive composition, a polyester pressure-sensitive adhesive composition, a polyamide pressure-sensitive adhesive composition, a polyether pressure-sensitive adhesive composition, a fluorine-based pressure-sensitive adhesive composition, a rubber pressure-sensitive adhesive composition, and the like. there is. Among the said adhesive composition, from viewpoints, such as transparency, adhesive force, reliability, rework property, a (meth)acrylic-type adhesive composition is used preferably. In this specification, "(meth)acryl" represents at least 1 sort(s) chosen from the group which consists of acryl and methacryl. The same applies to notations such as “(meth)acryloyl” and “(meth)acrylate”.

(Resin (A))

The pressure-sensitive adhesive composition contains a resin (A). Examples of the resin (A) include (meth)acrylic resins, urethane resins, silicone resins, polyester resins, polyamide resins, polyether resins, fluorine resins, natural rubbers, synthetic rubbers, and the like. Among these, it is preferable that resin (A) has (meth)acrylic-type resin as a main component (containing 50 mass % or more) from viewpoints, such as transparency, adhesive force, reliability, and rework property.

((meth)acrylic resin)

Specific examples of the (meth)acrylic resin that can be suitably used as the resin (A) of the pressure-sensitive adhesive composition include a structural unit derived from (meth)acrylic acid ester represented by the following formula (I) as a main component (50% by mass or more) It is a polymer (Hereinafter, this polymer may be called "(meth)acrylic-type resin (a1)").

In the formula (I), R ¹ represents a hydrogen atom or a methyl group, R ² is an alkyl group having 1 to 14 carbon atoms which may be substituted with an alkoxy group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms An aralkyl group having 7 to 21 carbon atoms is preferred. It is preferable that R< ² > is a C1-C14 alkyl group which may be substituted with a C1-C10 alkoxy group.

Specific examples of the (meth)acrylic acid ester represented by the formula (I) are (meth)methyl acrylate, (meth)ethyl acrylate, (meth)acrylic acid propyl, (meth)acrylate n-butyl, (meth)acrylic acid n-octyl straight-chain (meth)acrylic acid alkyl esters such as (meth)acrylic acid lauryl; branched (meth)acrylic acid alkyl esters such as (meth)acrylic acid isobutyl, (meth)acrylic acid 2-ethylhexyl, and (meth)acrylic acid isooctyl. Preferably carbon number of the alkyl part in (meth)acrylic-acid alkylester is 1-8, More preferably, it is 1-6.

When R ² is an alkyl group substituted with an alkoxy group, that is, when R ² is an alkoxyalkyl group, a specific example of the (meth)acrylic acid ester represented by the formula (I) is (meth)acrylic acid 2-methoxyethyl, (meth) ) and ethoxymethyl acrylate. Specific examples of the (meth)acrylic acid ester represented by the formula (I) in the case where R ² is an aralkyl group having 7 to 21 carbon atoms include benzyl (meth)acrylate and the like.

(meth)acrylic acid ester represented by Formula (I) may be used individually by 1 type, and may use 2 or more types together. Especially, it is preferable that (meth)acrylic-acid alkylester is included, and, as for (meth)acrylic acid ester, it is more preferable that (meth)acrylic-acid n-butyl is included. It is preferable that (meth)acrylic-type resin (a1) contains 50 mass % or more of n-butyl acrylate among all the monomers which comprise this. Of course, in addition to n-butyl acrylate, (meth)acrylic acid esters represented by other formulas (I) can also be used in combination.

The (meth)acrylic resin (a1) is usually a copolymer of the (meth)acrylic acid ester of the formula (I) and at least one other monomer typified by a monomer having a polar functional group. The monomer having a polar functional group is preferably a (meth)acrylic acid-based compound having a polar functional group. Examples of the polar functional group include a free carboxyl group, a hydroxyl group, an amino group, and a heterocyclic group including an epoxy group.

Specific examples of the monomer having a polar functional group include a monomer having a free carboxyl group such as (meth)acrylic acid and β-carboxyethyl (meth)acrylate; (meth)acrylic acid 2-hydroxyethyl, (meth)acrylic acid 3-hydroxypropyl, (meth)acrylic acid 4-hydroxybutyl, (meth)acrylic acid 2-(2-hydroxyethoxy)ethyl, (meth)acrylic acid Monomers having a hydroxyl group such as 2- or 3-chloro-2-hydroxypropyl, diethylene glycol mono (meth) acrylate; (meth)acryloylmorpholine, vinylcaprolactam, N-vinyl-2-pyrrolidone, vinylpyridine, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, 3 monomers having a heterocyclic group such as ,4-epoxycyclohexylmethyl (meth)acrylate, glycidyl (meth)acrylate, and 2,5-dihydrofuran; and monomers having an amino group different from the heterocycle such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and dimethylaminopropyl (meth)acrylate. The monomer which has a polar functional group may be used individually by 1 type, and may use 2 or more types together.

Among the above, from the viewpoint of the reactivity of the (meth)acrylic resin (a1), it is preferable to use a monomer having a hydroxyl group as one of the polar functional group-containing monomers constituting the (meth)acrylic resin (a1). In addition to the monomer having a hydroxyl group, it is also effective to use together a monomer having another polar functional group, such as a monomer having a free carboxyl group.

The (meth)acrylic resin (a1) is a monomer having one olefinic double bond and at least one aromatic ring in the molecule (however, those corresponding to the monomer represented by the formula (I) and the monomer having the polar functional group excluded) may further include a structural unit derived from Suitable examples include (meth)acrylic acid-based compounds having an aromatic ring. A suitable example of the (meth)acrylic acid type compound which has an aromatic ring is (meth)acrylic acid ester which has an aryloxyalkyl group like the phenoxyethyl group containing (meth)acrylic acid ester represented by following formula (II).

In the formula (II), R ³ represents a hydrogen atom or a methyl group, n represents an integer of 1 to 8, and R ⁴ represents a hydrogen atom, an alkyl group, an aralkyl group or an aryl group. When R ⁴ is an alkyl group, the carbon number may be about 1 to 9, in the case of an aralkyl group, the carbon number is about 7 to 11, and in the case of an aryl group, the carbon number may be about 6 to 10.

Examples of the alkyl group having 1 to 9 carbon atoms constituting R ⁴ in formula (II) include methyl, butyl, nonyl, and the like, and the aralkyl group having 7 to 11 carbon atoms, benzyl, phenethyl, naphthylmethyl, etc., having 6 carbon atoms Examples of the aryl group represented by to 10 include phenyl, tolyl, naphthyl and the like.

Specific examples of the phenoxyethyl group-containing (meth)acrylic acid ester represented by the formula (II) are (meth)acrylic acid 2-phenoxyethyl, (meth)acrylic acid 2-(2-phenoxyethoxy)ethyl, ethylene oxide modified (meth)acrylic acid ester of nonylphenol, (meth)acrylic acid 2-(o-phenylphenoxy)ethyl, and the like. Phenoxyethyl group containing (meth)acrylic acid ester may be used individually by 1 type, and may use 2 or more types together. Among them, (meth)acrylic acid ester containing a phenoxyethyl group is (meth)acrylic acid 2-phenoxyethyl, (meth)acrylic acid 2-(o-phenylphenoxy)ethyl and/or (meth)acrylic acid 2-(2-) It is preferred to include phenoxyethoxy)ethyl.

The (meth)acrylic resin (a1) contains, based on the total amount of solid content, the structural unit derived from the (meth)acrylic acid ester represented by the formula (I), preferably 60 to 99.9 mass%, more preferably contains in a proportion of 80 to 99.6 mass%, and a structural unit derived from a monomer having a polar functional group, preferably in a proportion of 0.1 to 20 mass%, more preferably in a proportion of 0.4 to 10 mass%, in the molecule The structural unit derived from the monomer which has one olefinic double bond and at least one aromatic ring, Preferably it is 0-40 mass %, More preferably, it can contain in the ratio of 6-12 mass %.

The (meth)acrylic resin (a1) is a (meth)acrylic acid ester represented by formula (I), a monomer having a polar functional group, and a monomer other than a monomer having one olefinic double bond and at least one aromatic ring in the molecule (Hereinafter, also referred to as "other monomers") may contain the structural unit derived from it. Specific examples of other monomers include a structural unit derived from (meth)acrylic acid ester having an alicyclic structure in a molecule, a structural unit derived from a styrene-based monomer, a structural unit derived from a vinyl-based monomer, and a plurality of (meth) ) The structural unit derived from the monomer which has an acryloyl group, the structural unit derived from a (meth)acrylamide monomer, etc. are included. Other monomers may be used individually by 1 type, and may use 2 or more types together.

The alicyclic structure has 5 or more carbon atoms normally, Preferably it is about 5-7 carbon atoms. Specific examples of (meth)acrylic acid esters having an alicyclic structure are (meth)acrylic acid isobornyl, (meth)acrylic acid cyclohexyl, (meth)acrylic acid dicyclopentanyl, (meth)acrylic acid cyclododecyl, (meth)acrylic acid methylcyclohexyl, (meth)acrylic acid trimethylcyclohexyl, (meth)acrylic acid tert-butylcyclohexyl, (meth)acrylic acid cyclohexylphenyl, alpha -ethoxy (meth)acrylic acid cyclohexyl, etc. are included.

Specific examples of the styrene-based monomer include styrene; alkyl styrenes such as methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene and octyl styrene; halogenated styrenes such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, and iodine styrene; nitrostyrene, acetylstyrene, methoxystyrene, divinylbenzene, and the like.

Specific examples of the vinyl-based monomer include fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, and vinyl laurate; vinyl halides such as vinyl chloride and vinyl bromide; vinylidene halides such as vinylidene chloride; nitrogen-containing aromatic vinyls such as vinylpyridine, vinylpyrrolidone and vinylcarbazole; conjugated diene monomers such as butadiene, isoprene and chloroprene; acrylonitrile, methacrylonitrile, and the like.

Specific examples of the monomer having a plurality of (meth)acryloyl groups in the molecule include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanedioldi (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate a monomer having a (meth)acryloyl group; and monomers having three (meth)acryloyl groups in the molecule, such as trimethylolpropane tri(meth)acrylate.

Specific examples of the (meth)acrylamide compound include N-methylol (meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N-(3-hydroxypropyl)(meth)acrylamide , N-(4-hydroxybutyl)(meth)acrylamide, N-(5-hydroxypentyl)(meth)acrylamide, N-(6-hydroxyhexyl)(meth)acrylamide, N,N- Dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-(3-dimethylaminopropyl)(meth)acrylamide, N-(1,1) -Dimethyl-3-oxobutyl)(meth)acrylamide, N-[2-(2-oxo-1-imidazolidinyl)ethyl](meth)acrylamide, 2-acryloylamino-2-methyl- 1-propanesulfonic acid, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)(meth)acrylamide, N-(propoxymethyl)(meth)acrylamide, N-(1-methylethoxymethyl) )(meth)acrylamide, N-(1-methylpropoxymethyl)(meth)acrylamide, N-(2-methylpropoxymethyl)(meth)acrylamide [alias: N-(isobutoxymethyl)(meth)acrylamide ) acrylamide], N-(butoxymethyl)(meth)acrylamide, N-(1,1-dimethylethoxymethyl)(meth)acrylamide, N-(2-methoxyethyl)(meth)acrylamide , N-(2-ethoxyethyl)(meth)acrylamide, N-(2-propoxyethyl)(meth)acrylamide, N-[2-(1-methylethoxy)ethyl](meth)acrylamide , N-[2-(1-methylpropoxy)ethyl](meth)acrylamide, N-[2-(2-methylpropoxy)ethyl](meth)acrylamide [alias: N-(2-isobutoxy) ethyl)(meth)acrylamide], N-(2-butoxyethyl)(meth)acrylamide, N-[2-(1,1-dimethylethoxy)ethyl](meth)acrylamide, and the like.

(meth)acrylic-type resin (a1) is 0-20 mass % normally of other monomers based on the quantity of the whole solid content, Preferably it contains in the ratio of 0-10 mass %.

From the viewpoint of the adhesion between the pressure-sensitive adhesive layer and the optical member, the (meth)acrylic resin (a1) preferably has a weight average molecular weight (Mw) of 500,000 or more in terms of standard polystyrene by gel permeation chromatography (GPC), 60 It is more preferable that it is ten thousand or more. Mw of (meth)acrylic-type resin (a1) is 1.7 million or less normally.

Resin (A) of a (meth)acrylic-type adhesive composition may contain 2 or more types of (meth)acrylic-type resin (a1). In addition to the (meth)acrylic resin (a1), the resin (A) has a structural unit derived from a (meth)acrylic resin different from this, such as (meth)acrylic acid ester of formula (I), and has a polarity (meth) having a (meth)acrylic resin (a2) having no functional group or a structural unit derived from the (meth)acrylic acid ester represented by the formula (I) as a main component, and having an Mw in the range of 0.5 million to 120,000 (meth) It may include an acrylic resin (a3) and the like.

(crosslinking agent (B))

The pressure-sensitive adhesive composition contains a crosslinking agent (B). When an adhesive composition contains a crosslinking agent (B), a crosslinked structure is formed in resin (A) contained in an adhesive composition, and favorable durability and rework property can be provided to the adhesive layer formed using the adhesive composition. .

A crosslinking agent (B) is a compound which reacts with the structural unit derived from the especially polar functional group containing monomer in resin (A), and bridge|crosslinks resin (A) like (meth)acrylic-type resin (a1). Specifically, an isocyanate-type compound, an epoxy-type compound, an aziridine-type compound, a metal chelate-type compound, etc. are illustrated. Of these, the isocyanate-based compound, the epoxy-based compound, and the aziridine-based compound have at least two functional groups capable of reacting with the polar functional group in the resin (A) in the molecule. A crosslinking agent (B) may be used individually by 1 type, and may use 2 or more types together.

An isocyanate type compound is a compound which has at least two isocyanato groups (-NCO) in a molecule|numerator. Specific examples of the isocyanate-based compound include tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, triphenylmethane triisocyanate; and the like. Moreover, the adduct body which made these isocyanate compounds react with polyols, such as glycerol or trimethylol propane, and what made the isocyanate compound a dimer, a trimer, etc. can be used as a crosslinking agent (B).

An epoxy-type compound is a compound which has at least two epoxy groups in a molecule|numerator. Specific examples of the epoxy compound include bisphenol A-type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, and 1,6-hexanediol. Diglycidyl ether, trimethylolpropane triglycidyl ether, N,N-diglycidylaniline, N,N,N',N'-tetraglycidyl-m-xylenediamine, 1,3-bis( N,N'-diglycidylaminomethyl)cyclohexane; and the like.

An aziridine-type compound is a compound which has in a molecule|numerator at least 2 backbone of the 3-membered ring which consists of one nitrogen atom and two carbon atoms, also called ethyleneimine. Specific examples of the aziridine-based compound include diphenylmethane-4,4'-bis(1-aziridinecarboxamide), toluene-2,4-bis(1-aziridinecarboxamide), triethylenemelamine, isop Taloylbis-1-(2-methylaziridine), tris-1-aziridinylphosphine oxide, hexamethylene-1,6-bis(1-aziridinecarboxamide), trimethylolpropane-tris-β -aziridinylpropionate, tetramethylolmethane-tris-β-aziridinylpropionate, and the like.

Specific examples of the metal chelate compound include compounds in which acetylacetone or ethyl acetoacetate is coordinated to a polyvalent metal such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium and zirconium. do.

A crosslinking agent (B) is 0.05 mass part or more and 5 mass parts or less normally with respect to 100 mass parts of solid content of resin (A) of an adhesive composition, Preferably it contains in the ratio of 0.1 mass part or more and 5 mass parts or less. There exists a tendency for durability of an adhesive layer to improve that content of a crosslinking agent (B) is 0.05 mass part or more.

The crosslinking agent (B) is usually 0.05 parts by mass or more and 5 parts by mass or less, preferably 0.1 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the solid content of the resin (A) (a total of these when two or more types are used). contained in a proportion of There exists a tendency for durability of an adhesive layer to improve that content of a crosslinking agent (B) is 0.05 mass part or more.

(Silane compound (C))

The pressure-sensitive adhesive composition contains a silane compound (C). A silane compound (C) can be used in order to improve the smoothness of the adhesive layer surface obtained using an adhesive composition, or in order to suppress the coating nonuniformity at the time of coating an adhesive composition.

The silane compound (C) has a Si-O-Si bond in its main chain, both ends of the main chain have functional groups other than hydrolysable groups, and the side chain has a functional group other than a carboxyl group (-COOH). The functional group constituting both ends of the main chain refers to a functional group bonded to Si positioned at the end of the Si—O—Si bond. A hydrolyzable group is directly couple|bonded with a silicon atom, and says the substituent which generates a silanol group (-SiOH) by a hydrolysis reaction or a condensation reaction. Examples of the hydrolyzable group include a halogen atom, an alkoxy group, an acyloxy group, and an alkenyloxy group. When a hydrolysable group has a carbon atom, it is preferable that it is 6 or less, and, as for the carbon number, it is more preferable that it is 4 or less. The functional group constituting the side chain refers to a functional group bonded to Si positioned in the main chain. The pressure-sensitive adhesive composition may contain 1 type or 2 or more types of silane compounds (C).

Both terminals of the main chain of the silane compound (C) are not particularly limited as long as they have a functional group other than a hydrolyzable group. For example, each independently preferably has an alkyl group, a halogenated alkyl group, a phenyl group or an aralkyl group.

Examples of the alkyl group include an alkyl group having 1 to 6 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. Examples of the halogenated alkyl group include those obtained by substituting one or more hydrogens in the alkyl group with a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. Examples of the aralkyl group include an aralkyl group having 7 to 16 carbon atoms. Examples of the aralkyl group include a benzyl group, a phenethyl group, a naphthylmethyl group, and a phenylpropyl group. It is preferable that both terminals of the main chain of a silane compound (C) are each independently an alkyl group, and it is preferable that all are methyl groups.

The side chain of the silane compound (C) is not particularly limited as long as it has a functional group other than a carboxyl group. For example, it is preferable to each independently have an alkyl group or an aralkyl group. As the alkyl group and the aralkyl group, those exemplified above can be used. It is more preferable that it is an alkyl group, and, as for the side chain of a silane compound (C), it is still more preferable that it is a C1-C6 alkyl group. It is preferable that any of the side chains of a silane compound (C) contain a methyl group.

Although a silane compound (C) will not specifically limit if it has the said structure, It is preferable to use as a leveling agent. The viscosity of the silane compound (C) at a temperature of 25° C. may be usually 300 mPa·s or more. The viscosity of the silane compound (C) is more preferably 500 mPa·s or more, still more preferably 800 mPa·s or more, 1000 mPa·s or more, 1100 mPa·s or more, and 1200 mPa·s or more. or more may be sufficient, and 2000 mPa*s or more may be sufficient as it. The viscosity in the temperature of 25 degreeC of a silane compound is 3000 mPa*s or less normally, and 2500 mPa*s or less may be sufficient as it. The viscosity of the silane compound (C) at a temperature of 25°C can be measured in accordance with the method for measuring the viscosity using a cone-plate rotational viscometer of JIS Z8803.

As the silane compound (C), a commercial item may be used. As a commercial item, specifically, the alkyl aralkyl modified silicone oil "SH203", "SH230", "SF-8410", "SF-8416", "SH-8400", "L-7001 by Dow Toray Corporation" ' and the like.

The silane compound (C) is usually 0.01 parts by mass or more, preferably 0.1 parts by mass or more, with respect to 100 parts by mass of the solid content of the resin (A) in the pressure-sensitive adhesive composition from the viewpoint of smoothness of the surface of the pressure-sensitive adhesive layer and coatability of the pressure-sensitive adhesive composition. and 1 mass part or more is more preferable, and it is 10 mass parts or less normally, It is preferable that it is 5 mass parts or less, It is more preferable that it is 3 mass parts or less, It is still more preferable that it is 1 mass part or less.

(Silane coupling agent (D))

The pressure-sensitive adhesive composition may include a silane coupling agent (D). When the pressure-sensitive adhesive composition contains the silane coupling agent (D), the heat resistance of the pressure-sensitive adhesive layer can be improved, and when the pressure-sensitive adhesive layer is bonded to a glass substrate or a conductive layer, the adhesive layer and the glass substrate or conductive layer, etc. It becomes easy to improve, and peeling resistance etc. can be improved.

The silane coupling agent (D) is a compound other than the silane compound (C), and is preferably a compound in which an arbitrary functional group is bonded to a silicon atom. Examples of the functional group bonded to the silicon atom include an organic group having a reactive functional group such as a hydrolyzable group such as an alkoxy group, a vinyl group, an amino group, an epoxy group, a halogenated alkyl group, a (meth) acroyl group, and a mercapto group. The silane coupling agent (D) is preferably a siloxane compound having a Si-O-Si bond in the main chain, and the siloxane compound preferably has a hydrolyzable group in the main chain. As a hydrolysable group, an above-mentioned thing is mentioned, It is preferable that it is an alkoxy group. The pressure-sensitive adhesive composition may contain one or more silane coupling agents (D).

As the silane coupling agent (D), for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane , N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3- Mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyldimethoxymethylsilane, 3-glycidoxypropylethoxydimethyl Silane etc. are mentioned.

The silane coupling agent (D) may be of a silicone oligomer type. When a silicone oligomer is expressed in the form of a (monomer) oligomer, the following are mentioned, for example.

3-mercaptopropyltrimethoxysilane-tetramethoxysilane copolymer,

3-mercaptopropyltrimethoxysilane-tetraethoxysilane copolymer,

3-mercaptopropyltriethoxysilane-tetramethoxysilane copolymer,

copolymers containing a mercaptopropyl group, such as a 3-mercaptopropyltriethoxysilane-tetraethoxysilane copolymer;

mercaptomethyltrimethoxysilane-tetramethoxysilane copolymer,

mercaptomethyltrimethoxysilane-tetraethoxysilane copolymer,

mercaptomethyltriethoxysilane-tetramethoxysilane copolymer,

mercaptomethyl group-containing copolymers such as mercaptomethyltriethoxysilane-tetraethoxysilane copolymers;

3-glycidoxypropyltrimethoxysilane-tetramethoxysilane copolymer,

3-glycidoxypropyltrimethoxysilane-tetraethoxysilane copolymer,

3-glycidoxypropyltriethoxysilane-tetramethoxysilane copolymer,

3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer,

3-glycidoxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-glycidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-glycidoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,

copolymers containing 3-glycidoxypropyl group, such as 3-glycidoxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,

3-methacryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,

3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,

3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,

3-methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-methacryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,

3-Methacryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer

Copolymers containing methacryloyloxypropyl groups, such as;

3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,

3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,

3-acryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,

3-acryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,

3-acryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-acryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-acryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,

3-Acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer

Copolymers containing acryloyloxypropyl groups, such as;

vinyltrimethoxysilane-tetramethoxysilane copolymer,

vinyltrimethoxysilane-tetraethoxysilane copolymer,

vinyltriethoxysilane-tetramethoxysilane copolymer,

vinyltriethoxysilane-tetraethoxysilane copolymer,

vinylmethyldimethoxysilane-tetramethoxysilane copolymer,

vinylmethyldimethoxysilane-tetraethoxysilane copolymer,

vinylmethyldiethoxysilane-tetramethoxysilane copolymer,

Vinylmethyldiethoxysilane-tetraethoxysilane copolymer

vinyl group-containing copolymers such as;

3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer,

3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer,

3-aminopropyltriethoxysilane-tetramethoxysilane copolymer,

3-aminopropyltriethoxysilane-tetraethoxysilane copolymer,

3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer,

3-Aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer

Copolymers containing amino groups, such as.

The viscosity of the silane coupling agent (D) at a temperature of 25°C is usually 250 mPa·s or less, preferably 200 mPa·s or less, 150 mPa·s or less, 100 mPa·s or less, and 30 mPa It may be s. The viscosity of the silane coupling agent (D) at a temperature of 25°C can be measured in accordance with the method for measuring the viscosity using a cone-plate rotational viscometer of JIS Z8803.

A silane coupling agent (D) is 0.01 mass part or more and 10 mass parts or less normally with respect to 100 mass parts of solid content of resin (A) of an adhesive composition, Preferably it contains in the ratio of 0.05 mass part or more and 5 mass parts or less. When content of a silane coupling agent (D) is 0.01 mass part or more, it is easy to improve the heat resistance of the adhesive layer formed using an adhesive composition, and it is easy to improve the adhesiveness of an adhesive layer, a glass substrate, etc. The bleed-out of the silane coupling agent (D) from an adhesive layer can be suppressed as content of a silane coupling agent (D) is 10 mass parts or less.

(Other ingredients)

The adhesive composition can contain other components other than resin (A), a crosslinking agent (B), a silane compound (C), and a silane coupling agent (D). As other components, one or more additives such as a crosslinking catalyst, a UV absorber, a weathering stabilizer, a tackifier, a plasticizer, a softener, a dye, a pigment, an inorganic filler, light scattering fine particles, and a tackifier may be included. there is.

The pressure-sensitive adhesive composition is usually prepared as a pressure-sensitive adhesive solution in which a compounding component is dissolved or dispersed by containing an organic solvent. It is preferable that the organic solvent is selected according to the kind of resin (A). Specific examples of the organic solvent include aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as hexane, heptane and pentane; ketones such as methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate and butyl acetate are included. The density|concentration of resin (A) in an adhesive liquid is 3-20 mass % normally.

<Adhesive layer>

The adhesive layer which concerns on this invention contains the said adhesive composition which concerns on this invention, and consists typically of the adhesive composition which concerns on this invention. The pressure-sensitive adhesive layer can be obtained by, for example, dissolving or dispersing each component constituting the pressure-sensitive adhesive composition in a solvent to obtain an pressure-sensitive adhesive solution, and applying and drying the pressure-sensitive adhesive solution on the surface of the optical layer or release film.

The adhesive layer which concerns on this invention can make mutually different the adhesive force with respect to the peeling film on the both surfaces. Therefore, also in the adhesive sheet which provided the peeling film which has the same peeling process layer on both surfaces of the adhesive layer mentioned later, when peeling a peeling film, a certain part of an adhesive layer peels with one peeling film, and an adhesive The other part of the layer is peeled off together with the peeling film of the other side, and problems such as partial separation of the pressure-sensitive adhesive layer can be suppressed. Thereby, a uniform adhesive layer can be formed in to-be-adhered members, such as an optical layer and a glass substrate.

<Adhesive sheet>

The adhesive sheet which concerns on this invention forms the peeling film which has the same release process layer on both surfaces of the said adhesive layer which concerns on this invention. A peeling film has the release process layer formed in the at least one surface of a base film and a base film, and the release process layer side is bonded by the adhesive layer. The release film having the same release treatment layer means a release film having the same peeling force when the release treatment layer side of the release film in which the release treatment layer is formed on the same substrate by the same release treatment is bonded to the same surface of the pressure-sensitive adhesive layer. say

In the pressure-sensitive adhesive sheet according to the present invention, the peeling force between one surface of the pressure-sensitive adhesive layer and the release-treated layer side of the release film is the first peeling force, and the release film is released from the other surface on the opposite side to one side of the pressure-sensitive adhesive layer. When the adhesive force between the treatment layers is the second peeling force, the first peeling force and the second peeling force are not the same but different from each other. The said adhesive layer differs from each other in the adhesive force with respect to a peeling film in the both surfaces. Therefore, even if it does not prepare the peeling film which has a different release treatment layer, by using the release film which has the same release treatment layer, the adhesive sheet from which 1st peeling force and 2nd peeling force differ can be obtained. Thereby, when peeling a peeling film from an adhesive sheet, problems, such as an adhesive layer isolate|separating partially, can be suppressed. The 1st peeling force and 2nd peeling force can be measured by the method as described in an Example.

The pressure-sensitive adhesive sheet can be obtained by, for example, applying and drying the pressure-sensitive adhesive solution on the release-treated side of the release film to form a pressure-sensitive adhesive layer, and laminating the release-treated side of the release film on the surface opposite to the release film of the pressure-sensitive adhesive layer. there is. In this case, the peeling force between the adhesive layer and the peeling film laminated|stacked on the adhesive layer tends to become larger than the peeling force between the peeling film and the adhesive layer to which the adhesive liquid was apply|coated.

The first peeling force and the second peeling force are each preferably 0.010 N/50 mm or more, more preferably 0.020 N/50 mm or more, still more preferably 0.030 N/50 mm or more, and 0.1 N/50 mm or less. It is preferable, and it is more preferable that it is 0.08 N/50 mm or less, and 0.06 N/50 mm or less may be sufficient. The absolute value of the difference between the first peeling force and the second peeling force is preferably 0.01 N/50 mm or more, more preferably 0.012 N/50 mm or more, 0.015 N/50 mm or more, and 0.09 N/50 mm or more. mm or less, 0.08 N/50 mm or less may be sufficient, and 0.06 N/50 mm or less may be sufficient as it.

As a peeling film used for an adhesive sheet, the film by which the mold release process was given to the base film formed using resin is mentioned. Although it does not specifically limit as resin which comprises a base film, For example, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarylate, etc. are mentioned. Moreover, although a well-known mold release process may just be performed as a mold release process performed to a base film, the method of coating mold release agents, such as a fluorine compound and a silicone compound, on a base film is preferable.

<Optical laminate>

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows an example of the optical laminated body which concerns on this invention. 2 and 3 are schematic cross-sectional views showing an example of the optical layer included in the optical laminate according to the present invention. 4 to 8 are schematic cross-sectional views showing another example of the layer structure of the optical laminate according to the present invention.

The optical laminate according to the present invention includes an optical layer and the pressure-sensitive adhesive layer according to the present invention. Since an adhesive layer can make mutually different the adhesive force with respect to the peeling film on the both surfaces when it is set as an adhesive sheet, a uniform adhesive layer can be formed in an optical laminated body by using an adhesive sheet.

For example, as shown in FIG. 1 , the optical laminate 1 includes the pressure-sensitive adhesive layer 20 on at least one surface of the optical layer 10 , and the pressure-sensitive adhesive layer 20 on both surfaces of the optical layer 10 . ) may have When the pressure-sensitive adhesive layer 20 is formed on the surface of the optical layer 10 , a primer layer is formed on the bonding surface of the optical layer 10 and/or the bonding surface of the pressure-sensitive adhesive layer 20 , or surface activation treatment, for example, plasma It is preferable to perform a treatment, a corona treatment, etc., and it is more preferable to perform a corona treatment.

The optical layer 10 may be a polarizing plate which has a resin film on the single side|surface or both surfaces of a polarizer. That is, the optical layer 10 may be a single-sided protective polarizing plate 10a having a first resin film 3 on one side of the polarizer 2, as shown in FIG. 2, and as shown in FIG. The double-sided protective polarizing plate 10b which has the 1st resin film 3 on one surface of the polarizer 2, and has the 2nd resin film 4 on the other surface may be sufficient. In the single-sided protection polarizing plate 10a shown in FIG. 2, the adhesive layer 20 is laminated|stacked on the surface on the opposite side to the 1st resin film 3 in the polarizer surface, ie, the polarizer 2 normally. It is preferable that the adhesive layer 20 is laminated|stacked on the polarizer 2 directly. In the double-sided protection polarizing plate 10b shown in FIG. 3, the adhesive layer 20 may be laminated|stacked on either outer surface of the 1st resin film 3 and the 2nd resin film 4, and may be laminated|stacked on both outer surfaces.

The optical laminated body 1 shown in FIG. 1 may contain the separator (release film) laminated|stacked on the outer surface of the adhesive layer 20. As shown in FIG. The separator is usually peeled off when the pressure-sensitive adhesive layer 20 is used (eg, when lamination with respect to an adherend member such as a conductive layer or a glass substrate). As a separator, the thing similar to the said peeling film can be used, and one of the two peeling films which an adhesive sheet has may be sufficient as it.

The optical laminate 1 is formed by coating and drying the above-mentioned pressure-sensitive adhesive solution (the one in which each component constituting the pressure-sensitive adhesive composition is dissolved or dispersed in a solvent) on the surface of the optical layer 10 to form the pressure-sensitive adhesive layer 20 . can be obtained Moreover, in the optical laminated body 1, it carries out similarly to the above on the release-treated surface of a peeling film, and forms the adhesive layer 20, and this adhesive layer 20 is laminated|stacked (transferred) on the surface of the optical layer 10. ) can also be obtained by

In addition, the optical laminated bodies 5 and 6 shown in FIGS. 4 and 5 are the optical layer 10 (single side protection polarizing plate 10a, double-sided protection polarizing plate 10b), the adhesive layer 20, and the conductive layer 30 ) in this order. The optical laminate 5 shown in FIG. 4 is an example using the single-sided protection polarizing plate 10a shown in FIG. 2 as the optical layer 10, The optical laminated body 6 shown in FIG. 5 is both surfaces shown in FIG. This is an example in which the protective polarizing plate 10b is used as the optical layer 10 . The pressure-sensitive adhesive layer 20 of the optical laminates 5 and 6 shown in FIGS. 4 and 5 is laminated on the conductive layer 30 so as to be in direct contact with the conductive layer 30 . The optical laminated bodies 5 and 6 may have the board|substrate 40 on the opposite side to the adhesive layer 20 of the conductive layer 30. The substrate 40 is, for example, a glass substrate or a resin film, as will be described later.

As for the optical laminated body 7 shown in FIG. 6, the optical laminated body 1 shown in FIG. 1 is laminated|stacked on the conductive layer 30 via the resin layer 50. As shown in FIG. The pressure-sensitive adhesive layer 20 is in direct contact with the resin layer 50 . The optical laminate 7 may have the board|substrate 40 on the opposite side to the adhesive layer 20 of the conductive layer 30. As shown in FIG.

The optical laminated body 8 shown in FIG. 7 is the same as the optical laminated body 7 shown in FIG. 6 except not having the resin layer 50 and the conductive layer 30. As shown in FIG. In this case, the pressure-sensitive adhesive layer 20 is laminated on the substrate 40 .

The optical laminated body shown in FIG. 8 is the same as the optical laminated body 7 shown in FIG. 6 except that the conductive layer 30 is patterned in a predetermined shape. The conductive layer 30 of the optical laminate shown in Fig. 8 can be used, for example, as a metal wiring layer (ie, an electrode layer) of a touch input element of a touch input type liquid crystal display device. In the optical laminate shown in FIG. 8, the resin layer 50 may be abbreviate|omitted. When laminating the pressure-sensitive adhesive layer 20 on the patterned conductive layer 30 , the pressure-sensitive adhesive layer 20 may have a portion not in contact with the conductive layer 30 .

The said optical laminated body can be used for image display apparatuses, such as a liquid crystal display device and an organic electroluminescent (EL) display device. The liquid crystal display device or the organic EL display device may be a touch input type display device having a touch panel function.

(optical layer)

The optical layer may be various optical films (films having optical properties) that can be inserted into an image display device such as a liquid crystal display device. Examples of the optical layer include a polarizer, a polarizing plate, a retardation film, a brightness enhancing film, an anti-glare film, an antireflection film, a diffusion film, and a light collecting film. A single layer structure may be sufficient as an optical layer, and a multilayer structure may be sufficient as it.

(polarizer)

The polarizer is a layer or film having a function of selectively transmitting linearly polarized light in one direction from natural light. As a polarizer, the film which adsorbed and orientated the dichroic dye to the polyvinyl alcohol-type resin film is mentioned, for example. As a dichroic dye, an iodine, a dichroic organic dye, etc. are mentioned. Moreover, the coating type polarizing film which coated the dichroic dye of a lyotropic liquid crystal state on the base film, and orientation and fixed the polarizer may be sufficient. These polarizers are called absorption type polarizers because they selectively transmit linearly polarized light in one direction from natural light and absorb linearly polarized light in the other direction.

The polarizer is not limited to an absorption polarizer, and a reflective polarizer that selectively transmits linearly polarized light in one direction from natural light and reflects linearly polarized light in another direction, or a scattering type that scatters linearly polarized light in the other direction. Although it may be a polarizer, an absorption type polarizer is preferable at the point which is excellent in visibility. Among them, a polyvinyl alcohol-based polarizing film composed of a polyvinyl alcohol-based resin film is more preferable, and a polyvinyl alcohol-based polarizing film in which a dichroic dye such as iodine or a dichroic dye is adsorbed and oriented to a polyvinyl alcohol-based resin film. A film is more preferable, and the polyvinyl alcohol-type polarizing film which adsorbed and orientated iodine to the polyvinyl alcohol-type resin film is especially preferable.

As polyvinyl alcohol-type resin, what saponified polyvinyl acetate-type resin can be used. Examples of the polyvinyl acetate-based resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and a copolymer of vinyl acetate and other copolymerizable monomers. Examples of the other monomer copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having an ammonium group.

The saponification degree of polyvinyl alcohol-type resin is 85 mol% or more and 100 mol% or less normally, and 98 mol% or more is preferable. The polyvinyl alcohol-based resin may be modified, for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The average degree of polymerization of polyvinyl alcohol-type resin is 1000 or more and 10000 or less normally, and 1500 or more and 5000 or less are preferable. The average degree of polymerization of polyvinyl alcohol-type resin can be calculated|required based on JISK6726:1994.

What formed such a polyvinyl alcohol-type resin into a film is used as a raw film of the polarizing film comprised with the polyvinyl alcohol-type resin film. The method for forming a polyvinyl alcohol-type resin into a film is not specifically limited, A well-known method is employ|adopted. The thickness of the polyvinyl alcohol-based raw film is, for example, 150 µm or less, preferably 100 µm or less (eg, 50 µm or less), and 5 µm or more.

The polarizing film comprised from the polyvinyl alcohol-type resin film can be manufactured by a well-known method. Specifically, the process of uniaxially stretching a polyvinyl alcohol-type resin film; The step of adsorbing a dichroic dye by dyeing a polyvinyl alcohol-type resin film with a dichroic dye; a process of treating the polyvinyl alcohol-based resin film to which the dichroic dye has been adsorbed with an aqueous boric acid solution (crosslinking treatment); and washing with water after treatment with an aqueous boric acid solution.

The thickness of the polarizer can be 40 µm or less, preferably 30 µm or less (eg, 20 µm or less, further 15 µm or less, further 10 µm or less or 8 µm or less). According to the method described in Japanese Patent Application Laid-Open No. 2000-338329 or Japanese Patent Application Laid-Open No. 2012-159778, a thin-film polarizer can be manufactured more easily, and the thickness of the polarizer is, for example, 20 µm or less, further 15 µm or less, Furthermore, it becomes easier to set it as 10 micrometers or less or 8 micrometers or less. The thickness of the polarizer is usually 2 µm or more. Making the thickness of a polarizer small is advantageous for thickness reduction of the optical laminated body containing a polarizing plate, and the image display apparatus containing this.

(1st, 2nd resin film)

The first resin film 3 and the second resin film 4 are formed on the polarizer 2, for example, may be a protective film for protecting the polarizer 2, which has optical functions such as retardation film to be described later. A protective film may be sufficient. The first resin film 3 and the second resin film 4 are each formed of a light-transmitting (preferably optically transparent) thermoplastic resin, such as a chain polyolefin-based resin (polypropylene-based resin, etc.), a cyclic polyolefin-based resin ( polyolefin-based resins such as norbornene-based resins; Cellulose ester-type resin, such as a triacetyl cellulose and a diacetyl cellulose; polyester-based resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate; polycarbonate-based resin; (meth)acrylic resin; polystyrene-based resin; Or it may be a film made of a mixture or copolymer thereof.

The first resin film 3 and the second resin film 4 may be either an unstretched film or a uniaxially or biaxially stretched film, respectively. The biaxial stretching may be simultaneous biaxial stretching simultaneously stretching in two stretching directions, or sequential biaxial stretching stretching in a second direction different from this after stretching in the first direction.

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

The cyclic polyolefin-based resin is a generic term for a resin containing, as a polymerization unit, a cyclic olefin including norbornene, tetracyclododecene (another name: dimethanooctahydronaphthalene), or a derivative thereof. Examples of the cyclic polyolefin-based resin include a ring-opened (co)polymer of a cyclic olefin and a hydrogenated product thereof, an addition polymer of a cyclic olefin, a copolymer of a cyclic olefin and a chain olefin such as ethylene or propylene or an aromatic compound having a vinyl group, and these unsaturated and modified (co)polymers modified with carboxylic acid or a derivative thereof. Among them, norbornene-based resins using norbornene-based monomers such as norbornene and polycyclic norbornene-based monomers are preferably used as cyclic olefins.

Cellulose ester-type resin may be resin by which at least one part of the hydroxyl group in a cellulose was acetic acid esterified, and the mixed ester by which the acetic acid esterification was carried out partly, and the other acid esterification part is esterified. The cellulose ester-based resin is preferably an acetyl cellulose-based resin. Examples of the acetyl cellulose-based resin include triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, and cellulose acetate butyrate.

Polyester-type resin is resin other than the said cellulose-ester-type resin which has an ester bond, and what consists of polycondensate of polyhydric carboxylic acid or its derivative(s), and polyhydric alcohol is common. Examples of the polyester-based resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexanedimethyl terephthalate, and polycyclohexanedimethyl naphthalate. Phthalate etc. are mentioned. Among them, polyethylene terephthalate is preferably used from the viewpoints of mechanical properties, solvent resistance, scratch resistance, cost, and the like. Polyethylene terephthalate refers to a resin in which 80 mol% or more of the repeating unit is composed of ethylene terephthalate, and a structural unit derived from other copolymerization components (dicarboxylic acid components such as isophthalic acid; diol components such as propylene glycol) may contain

Polycarbonate-type resin is polyester formed from carbonic acid, glycol, or bisphenol. Especially, aromatic polycarbonate which has diphenyl alkane in a molecular chain is used preferably from a viewpoint of heat resistance, weather resistance, and acid resistance. Examples of polycarbonate include 2,2-bis(4-hydroxyphenyl)propane (also known as bisphenol A), 2,2-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl) and polycarbonates derived from bisphenols such as cyclohexane, 1,1-bis(4-hydroxyphenyl)isobutane, and 1,1-bis(4-hydroxyphenyl)ethane.

A (meth)acrylic-type resin is a polymer containing the structural unit derived from a (meth)acrylic-type monomer, A methacrylic acid ester and an acrylic acid ester are mentioned as a (meth)acrylic-type monomer.

Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, n-, i- or t-butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, methacrylic acid 2 -Ethylhexyl, 2-hydroxyethyl methacrylate, etc. are mentioned.

Examples of the acrylic acid ester include ethyl acrylate, n-, i- or t-butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and the like.

The (meth)acrylic-type resin may be the polymer which consists only of the structural unit derived from a (meth)acryl monomer, and may contain the other structural unit.

In one preferred embodiment, (meth)acrylic resin contains methyl methacrylate as a copolymerization component, or contains methyl methacrylate and methyl acrylate. In one preferred embodiment, the (meth)acrylic resin may be a polymer (containing 50 mass% or more) containing methacrylic acid ester as a main monomer, and is a copolymer in which methacrylic acid ester and other copolymerization components are copolymerized. it is preferable

The glass transition temperature of (meth)acrylic-type resin becomes like this. Preferably they are 80 degreeC or more and 160 degrees C or less. The glass transition temperature is determined by adjusting the polymerization ratio of the methacrylic acid ester-based monomer and the acrylic acid ester-based monomer, the carbon chain length of each ester group, the type of functional group they have, and the polymerization ratio of the polyfunctional monomer to the entire monomer. Controllable.

As a means for increasing the glass transition temperature of the (meth)acrylic resin, it is also effective to introduce a ring structure into the main chain of the polymer. The ring structure is preferably a heterocyclic structure such as a cyclic acid anhydride structure, a cyclic imide structure, and a lactone structure. Specifically, Cyclic acid anhydride structures, such as a glutaric anhydride structure and a succinic anhydride structure; cyclic imide structures such as a glutalimide structure and a succinimide structure; and lactone ring structures such as butyrolactone and valerolactone. There exists a tendency which can make high the glass transition temperature of (meth)acrylic-type resin, so that content of the ring structure in a principal chain is large. The cyclic acid anhydride structure and the cyclic imide structure are introduced by copolymerizing a monomer having a cyclic structure such as maleic anhydride and maleimide; a method of introducing a cyclic acid anhydride structure by dehydration/demethanol condensation reaction after polymerization; It can be introduced by, for example, a method of introducing a cyclic imide structure by reacting an amino compound. The resin (polymer) having a lactone ring structure is prepared by preparing a polymer having a hydroxyl group and an ester group in the polymer chain, and then heating the hydroxyl group and the ester group in the obtained polymer by heating, if necessary, a catalyst such as an organophosphorus compound. It can be obtained by a method of cyclization condensation in the presence of a lactone ring structure.

The (meth)acrylic resin and the thermoplastic resin film formed from it may contain the additive as needed. Examples of the additive include a lubricant, an antiblocking agent, a heat stabilizer, an antioxidant, an antistatic agent, a light resistance, an impact resistance improving agent, and a surfactant. These additives can be used also when using other thermoplastic resins other than a (meth)acrylic-type resin as a thermoplastic resin which comprises a thermoplastic resin film.

The (meth)acrylic resin may contain the acrylic rubber particle which is an impact modifier from viewpoints, such as the film forming property with respect to a film, and the impact resistance of a film. Acrylic rubber particles are particles containing an elastic polymer mainly composed of an acrylic acid ester as an essential component, and include those having a single-layer structure substantially composed of only the elastic polymer, and those having a multi-layer structure containing this elastic polymer as one layer.

As an example of the said elastic polymer, the crosslinked elastic copolymer which has alkyl acrylate as a main component and copolymerized this with other copolymerizable vinylic monomer and a crosslinkable monomer is mentioned. Examples of the alkyl acrylate used as the main component of the elastic polymer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and the like, and those having an alkyl group having 1 to 8 carbon atoms, and acrylic acid having an alkyl group having 4 or more carbon atoms. Alkyl is preferably used.

As another vinylic monomer copolymerizable with the said alkyl acrylate, the compound which has one polymerizable carbon-carbon double bond in a molecule|numerator is mentioned, More specifically, Methacrylic acid esters, such as methyl methacrylate; aromatic vinyl compounds such as styrene; Vinyl cyan compounds, such as acrylonitrile, etc. are mentioned.

Examples of the crosslinkable monomer include a crosslinkable compound having at least two polymerizable carbon-carbon double bonds in the molecule, and more specifically, ethylene glycol di(meth)acrylate and butanediol di(meth)acrylate (meth)acrylates of polyhydric alcohols, such as; alkenyl esters of (meth)acrylic acid such as allyl (meth)acrylate; Divinylbenzene etc. are mentioned.

A laminate of a film made of a (meth)acrylic resin containing no rubber particles and a film made of a (meth)acrylic resin containing rubber particles may be a thermoplastic resin film bonded to the optical layer 10 . In addition, a (meth)acrylic resin layer is formed on one side or both sides of the retardation expression layer made of a resin different from the (meth)acrylic resin, and the retardation is expressed as a thermoplastic resin film bonded to the optical layer 10 . You may.

The first resin film 3 and the second resin film 4 each include at least one thermoplastic resin selected from the group consisting of a cellulose ester-based resin, a polyester-based resin, a (meth)acrylic resin, and a cyclic polyolefin-based resin. It is preferable that it is a film, and it is more preferable that it is a cellulose-ester-type resin film, a polyester-type resin film, a (meth)acrylic-type resin film, or a cyclic polyolefin-type resin film.

The first resin film 3 and/or the second resin film 4 is a UV absorber, an infrared absorber, an organic dye, a pigment, an inorganic dye, an antioxidant, an antistatic agent, a surfactant, a lubricant, a dispersant, a heat stabilizer, etc. may contain. When the optical laminate is applied to an image display device, by arranging the thermoplastic resin film containing the ultraviolet absorber on the visible side of the image display element (eg, liquid crystal cell, organic EL display element, etc.), the ultraviolet rays of the image display element deterioration can be suppressed. Examples of the ultraviolet absorber include a salicylic acid ester-based compound, a benzophenone-based compound, a benzotriazole-based compound, a cyanoacrylate-based compound, and a nickel complex salt-based compound.

The 1st resin film 3 and the 2nd resin film 4 may be films comprised from the same thermoplastic resin, and the films comprised from mutually different thermoplastic resins may be sufficient as them. The 1st resin film 3 and the 2nd resin film 4 may be the same or different in thickness, the presence or absence of an additive, the kind, retardation characteristic, etc.

The first resin film 3 and/or the second resin film 4 has a hard coat layer, an anti-glare layer, an antireflection layer, a light diffusion layer, an antistatic layer, on its outer surface (the surface opposite to the optical layer 10); You may be equipped with surface treatment layers (coating layer), such as a pollution prevention layer and a conductive layer, and a protection film. The protection film is a film used for the purpose of protecting the surface of the optical layer 10, such as a polarizing plate, from damage or contamination, and the optical laminate 1 shown in FIG. 1 is bonded on, for example, a conductive layer or a glass substrate. After that, it is customary to peel off.

The protection film is usually composed of a base film and an adhesive layer laminated thereon. The base film may include a thermoplastic resin such as a polyolefin-based resin such as a polyethylene-based resin or a polypropylene-based resin; polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate; polycarbonate-based resin; (meth)acrylic resin etc. can be comprised.

The thickness of the first resin film 3 and the second resin film 4 is usually 5 μm or more and 200 μm or less, respectively, preferably 10 μm or more and 120 μm or less, more preferably 10 μm or more and 85 μm or less, further Preferably, it is 15 micrometers or more and 65 micrometers or less. The thickness of the 1st resin film 3 and the 2nd resin film 4 may be 50 micrometers or less, respectively, and 40 micrometers or less may be sufficient as them. Making the thickness of the 1st resin film 3 and the 2nd resin film 4 small is advantageous for thickness reduction of the optical laminated body (polarizing plate) and the image display apparatus containing this.

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

As the water-based adhesive, a common water-based adhesive (eg, an adhesive made of a polyvinyl alcohol-based resin aqueous solution, a water-based two-part urethane-based emulsion adhesive, an aldehyde compound, an epoxy compound, a melamine-based compound, a methylol compound, an isocyanate compound, an amine compound, a polyvalent crosslinking agents such as metal salts); Among these, the aqueous adhesive agent which consists of polyvinyl alcohol-type resin aqueous solution can be used suitably. In addition, in the case of using a water-based adhesive, the polarizer 2 and the first resin film 3 and/or the second resin film 4 are bonded, and then dried to remove water contained in the water-based adhesive. It is preferable to carry out the process. After the drying step, for example, 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 irradiating active energy rays such as ultraviolet rays or electron beams, for example, a curable composition containing a polymerizable compound and a photoinitiator, a curable composition containing a photoreactive resin, a binder resin, and a light A curable composition containing a reactive crosslinking agent etc. are mentioned, Preferably it is an ultraviolet curable adhesive agent.

When using an active energy ray-curable adhesive agent, after bonding the polarizer 2 and the 1st resin film 3 and/or the 2nd resin film 4 together, a drying process is performed as needed, Then, an active energy ray A curing step of curing the active energy ray-curable adhesive by irradiating it is performed. Although the light source of an active energy ray is not specifically limited, The ultraviolet-ray which has light emission distribution at a wavelength of 400 nm or less is preferable.

As a method of bonding the polarizer 2 and the first resin film 3 and/or the second resin film 4 to each other, at least one of these bonding surfaces is subjected to saponification treatment, corona treatment, plasma treatment, or the like. The method of performing an activation process, etc. are mentioned. When a resin film is bonded to both surfaces of the polarizer 2, the adhesive agent for bonding these resin films together may be an adhesive of the same type, or a different type of adhesive agent may be sufficient as it.

(retardation film)

Examples of the retardation film include a stretched film obtained by uniaxially stretching or biaxially stretching a translucent thermoplastic resin; a film in which a liquid crystal compound such as a discotic liquid crystal or a nematic liquid crystal is aligned and fixed; Those in which the said liquid crystal layer was formed on the base film, etc. are mentioned. In addition, in this specification, it is contained in the zero retardation film retardation film. A base film is a film which consists of a thermoplastic resin normally, and an example of a thermoplastic resin is cellulose ester-type resin, such as a triacetyl cellulose. As a translucent thermoplastic resin, resin etc. which comprise the said 1st resin film 3 and the 2nd resin film 4 are mentioned.

The zero retardation film refers to a film having an in-plane retardation value Re and a thickness direction retardation value Rth of -15 to 15 nm. This retardation film is used suitably for the liquid crystal display device of an IPS mode. The in-plane retardation value Re and the thickness direction retardation value Rth are preferably both -10 to 10 nm, more preferably both -5 to 5 nm. 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 Re and the thickness direction retardation value Rth are, respectively, the following formulas:

Re=(n _x -n _y )×d

Rth=[(n _x +n _y )/2-n _z ]×d

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

For the zero retardation film, for example, a resin film made of a polyolefin-based resin such as a cellulose-based resin, a chain polyolefin-based resin and a cyclic polyolefin-based resin, a polyethylene terephthalate-based 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 from the viewpoint of easy control of the retardation value and easy availability.

As a film in which optical anisotropy was expressed by application and orientation of the liquid crystalline compound,

First form: a retardation film in which the rod-shaped liquid crystal compound is oriented in a horizontal direction with respect to a supporting substrate;

Second form: a retardation film in which the rod-shaped liquid crystal compound is oriented in a vertical direction with respect to a supporting substrate;

Third form: a retardation film in which the rod-shaped liquid crystal compound changes the direction of the orientation in a spiral in the plane;

Fourth form: retardation film in which disc-shaped liquid crystal compound is oriented obliquely,

Fifth aspect: a biaxial retardation film in which a disk-shaped liquid crystal compound is oriented in a direction perpendicular to a supporting substrate is mentioned.

For example, as an optical layer used for an organic electroluminescent display, a 1st form, a 2nd form, and a 5th form are used suitably. Alternatively, these may be laminated and used.

When the retardation film is a layer made of a polymer in an orientation state of the polymerizable liquid crystal compound (hereinafter, sometimes referred to as an "optically anisotropic layer"), the retardation film preferably has reverse wavelength dispersion. Reverse wavelength dispersion is an optical property in which the liquid crystal alignment in-plane retardation value at a short wavelength becomes smaller than the liquid crystal alignment in-plane retardation value at a long wavelength, and preferably, the retardation film satisfies the following formulas (1) and (2) will be. In addition, Re(λ) represents an in-plane retardation value with respect to light having a wavelength of λ nm.

Re(450)/Re(550)≤1 (One)

1≤Re(630)/Re(550) (2)

When the retardation film is the first form and has reverse wavelength dispersion, it is preferable because coloration at the time of black display in a display device is reduced, and in Formula (1), if 0.82≤Re(450)/Re(550)≤0.93 more preferably. 120≤Re(550)≤150 is more preferable.

As a polymeric liquid crystal compound in the case where retardation film is a film which has an optically anisotropic layer, "3. 8. 6 Network (completely cross-linked)”, “6. 5. 1 liquid crystal material b. A compound having a polymerizable group among the compounds described in "Polymerizable Nematic Liquid Crystal Material", and Japanese Patent Application Laid-Open No. 2010-31223, JP 2010-270108 , JP 2011-6360 , JP 2011- The polymerizable liquid crystal compound of Unexamined-Japanese-Patent No. 207765, Unexamined-Japanese-Patent No. 2016-81035, and International Publication No. 2017/043438 is mentioned.

As a method of manufacturing a retardation film with the polymer in the orientation state of a polymeric liquid crystal compound, the method of Unexamined-Japanese-Patent No. 2010-31223 is mentioned, for example.

In the case of the second aspect, the in-plane retardation value Re (550) may be adjusted in the range of 0 to 10 nm, preferably in the range of 0 to 5 nm, and the retardation value Rth in the thickness direction is -10 to -300 nm. range, preferably in the range of -20 to -200 nm. The retardation value Rth in the thickness direction, which means refractive index anisotropy in the thickness direction, may be calculated from the in-plane retardation value Re and the retardation value R50 measured by tilting the in-plane fast axis by 50 degrees with the inclination axis. That is, the retardation value Rth in the thickness direction is the in-plane retardation value Re, the retardation value R50 measured by tilting the fast axis by 50 degrees with the inclination axis as the inclination axis, the thickness d of the retardation film, and the average refractive index n ₀ of the retardation film. n _x , n _y and n _z are obtained by (4) to (6), and can be calculated by substituting them into Equation (3).

Rth=[(n _x +n _y )/2-n _z ]×d (3)

Re=(n _x -n _y )×d (4)

R50=(n _x -n _y ')×d/cos(φ) (5)

(n_x+n_y+n_z)/3=n₀ (6)

here,

φ=sin ^-1 [sin(40°)/n ₀ ]

n _y '=n _y × n _z /[n _y ² ×sin ² (φ)+n _z ² ×cos ² (φ)] ^1/2

The retardation film may be a multilayer film having two or more layers. For example, a protective film is laminated on one side or both sides of the retardation film, or two or more retardation films are laminated through an adhesive or an adhesive.

(conductive layer)

The conductive layer 30 may be, for example, a transparent electrode layer or a metal layer. Examples of the transparent electrode layer include layers composed of indium tin oxide, tin oxide, indium oxide, zinc oxide, titanium oxide, gallium oxide, aluminum oxide, indium zinc oxide, gallium zinc oxide, aluminum zinc oxide, and mixtures thereof. . It is preferable that it is the point of electroconductivity and visible light transmittance|permeability. The metal layer includes one type of simple metal selected from the group consisting of aluminum, copper, silver, iron, tin, zinc, nickel, molybdenum, chromium, tungsten, and lead, and two or more types of metal elements selected from these groups and a layer containing at least one of at least one selected from the alloys to be used. Among them, from the viewpoint of conductivity, it is preferably a metal layer containing at least one single metal selected from aluminum, copper, silver and gold, and more preferably at least one metal selected from aluminum, copper, and silver. This is the layer that contains the group.

The conductive layer 30 may be a layer in which a metal mesh in which a thin metal wiring layer is disposed on a substrate, metal nanoparticles, or metal nanowires is added in a binder.

The preparation method of the conductive layer 30 is not specifically limited, What was formed by the vacuum vapor deposition method, the sputtering method, the ion plating method, the inkjet printing method, and the gravure printing method may be sufficient. The conductive layer 30 is preferably a transparent electrode layer and a metal layer formed by sputtering, inkjet printing, or gravure printing, and more preferably a transparent electrode layer and a metal layer formed by sputtering. Although the thickness of the conductive layer 30 is not specifically limited, Usually, 3 micrometers or less, Preferably it is 1 micrometer or less, More preferably, it is 0.8 micrometer or less, Usually, it is 0.01 micrometer or more. In addition, when the conductive layer 30 is a metal wiring layer (eg, metal mesh), the line width of the metal wiring is usually 10 μm or less, preferably 5 μm or less, more preferably 3 μm or less, usually 0.5 more than μm.

(Board)

The substrate 40 may be a transparent substrate included in the touch input element, preferably a glass substrate or a resin film. As a material of the said glass substrate, soda-lime glass, low alkali glass, alkali free glass, etc. can be used. As resin which comprises the resin film, resin etc. which comprise the said 1st resin film 3 and the 2nd resin film 4 are mentioned, for example.

(resin layer)

As resin which forms the resin layer 50, resin etc. which comprise the said 1st resin film or the 2nd resin film are mentioned, for example. In addition, the resin layer 50 may be a hardened|cured material layer of curable resin. As curable resin which can form the resin layer 50, a well-known thing can be used, For example, the thing of Unexamined-Japanese-Patent No. 2009-217037 is mentioned.

Example

Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited by these examples. Unless otherwise indicated, "%" and "part" in an Example and a comparative example are mass % and mass part.

[Confirmation of peeling state and measurement of peeling force]

Using the adhesive sheet obtained by each Example and the comparative example, confirmation of the peeling state and the measurement of peeling force were performed in the following procedure.

(Preparation of test piece)

The pressure-sensitive adhesive sheet obtained in each Example and Comparative Example was cured under conditions of a temperature of 23°C and a humidity of 55% RH for 1 week. A test piece having a size of 5 cm in width and 12 cm in length was cut out from the adhesive sheet after curing using a super cutter.

(Measurement of 1st peeling force between an adhesive layer and the release process layer side of a 1st peeling film)

On the entire surface of one side of a glass substrate (EAGLE XG, manufactured by Corning), double-sided tape (Nice Stack (trade name), manufactured by Nichiban Co., Ltd.) with a width of 25 mm x 22 cm in length was bonded side by side in the long side direction, and prepared above. The opposite side to the adhesive layer of the 2nd peeling film (a peeling film formed so that the adhesive layer coated and formed on the 1st peeling film might be covered) of the test piece was bonded, and this double-sided tape and the glass substrate were bonded together. In this state, using an autograph (AGS-50NX, manufactured by Shimadzu Corporation), one end in the longitudinal direction (one of 5 cm in width) of the first release film (the release film on the side to which the pressure-sensitive adhesive composition was applied when producing the pressure-sensitive adhesive sheet) side), the pressure-sensitive adhesive layer was peeled from the pressure-sensitive adhesive layer by pulling it in a direction of 180° at a peeling rate of 300 mm/min under conditions of a temperature of 23° C. and a humidity of 55% RH, and the peeling force at that time was recorded on a chart. Since the data is not stable immediately after the start of the measurement and immediately after the end of the measurement, 20% of the data after the start of the measurement and 20% of the data after the end of the measurement are cut, and the average value is calculated only in the range of the relatively stable middle part of 60%, and this is removed. It was set as 1 peeling force [N/50 mm].

(Measurement of 2nd peeling force between an adhesive layer and the release process layer side of a 2nd peeling film)

The 1st peeling film was peeled from the test piece prepared above, and the exposed adhesive layer and the glass substrate (EAGLE XG, the Corning company make) were bonded together. In this state, except that the second peeling film was peeled off, the peeling force was recorded on the chart in the same procedure as in the measurement of the first peeling force, and the second peeling force [N/50 mm] was calculated based on the obtained data. did.

(Calculation of difference in peel force)

The absolute value of the difference of the 1st peeling force and 2nd peeling force obtained above was made into the peeling force difference [N/50mm].

(Confirmation of peeling state)

At the time of peeling force measurement, the peeling state was confirmed visually. The case where the peeling film could be peeled without an adhesive layer being partly separated was evaluated as A, and the case where the adhesive layer was separated by peeling of a peeling film was evaluated as B.

<Production Examples 1 and 2: Preparation of (meth)acrylic resin>

In a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, a solution obtained by mixing a monomer having the composition shown in Table 1 (the numerical value in Table 1 is parts by mass) with 81.8 parts of ethyl acetate was placed. After replacing the air in the reaction vessel with nitrogen gas, the internal temperature was set to 60°C. Then, the solution which melt|dissolved 0.12 part of azobisisobutyronitrile in 10 parts of ethyl acetate was added. After maintaining the internal temperature at 54 to 56°C until 12 hours have elapsed from the addition of azobisisobutyronitrile, ethyl acetate is added to adjust the polymer concentration to 20%, and an ethyl acetate solution of (meth)acrylic resin got

The weight average molecular weight Mw and number average molecular weight Mn of the (meth)acrylic resin (A1) obtained in Preparation Example 1 and the (meth)acrylic resin (A2) obtained in Preparation Example 2 were measured. The weight average molecular weight Mw and the number average molecular weight Mn are a column in the GPC apparatus, 4 "TSKgel XL" manufactured by Tosoh Corporation, and 1 "Shodex GPC KF-802" manufactured by Showa Denko Co., Ltd. A total of 5 Dogs were placed in series, tetrahydrofuran was used as the eluent, sample concentration 5 mg/mL, sample introduction amount 100 μL, temperature 40° C., and flow rate 1 mL/min were measured in terms of standard polystyrene. .

The abbreviations in the column of "monomer composition" in Table 1 mean the following monomers.

BA: n-butyl acrylate

MA: methyl acrylate

HEA: Acrylic acid 2-hydroxyethyl

AA: acrylic acid

BMAA: Butoxymethylacrylamide

PEA: Acrylic acid 2-phenoxyethyl

[Examples 1 to 10, 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 crosslinking agent (B) shown in Table 2, the silane compound (C), the silane coupling agent with respect to 100 parts of the solid content of the solution. (D) and other components were mixed in the quantity (mass part) shown in Table 2, respectively, ethyl acetate was further added so that solid content concentration might be set to 14 %, and the adhesive composition was obtained. The compounding quantity of each compounding component shown in Table 2 is the number of parts by mass as an active ingredient contained there when the used product contains a solvent etc.

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

(crosslinking agent (B))

B: Colonate L (ethyl acetate solution of trimethylolpropane adduct of tolylene diisocyanate: solid content concentration of 75 mass%, manufactured by Tosoh Corporation)

(Silane compound (C))

C1: Alkyl aralkyl modified silicone oil, trade name "SH203" obtained from Dow Toray Co., Ltd., contains a Si-O-Si bond in the main chain, both ends of the main chain are methyl groups, and the side chain is a methyl group or an alkyl group Compound (viscosity: 1208 mPa s)

C2: Alkyl aralkyl modified silicone oil, trade name "SH230" obtained from Dow Toray Co., Ltd., contains a Si-O-Si bond in the main chain, both ends of the main chain are methyl groups, and the side chain is a methyl group or an alkyl group Compound (viscosity: 1348 mPa s)

(Silane coupling agent (D))

D1: 3-glycidoxypropyltrimethoxysilane, trade name "KBM403" obtained from Shin-Etsu Chemical Co., Ltd. (viscosity: 4.2 mPa·s)

D2: X-41-1810 (mercapto equivalent 450 g/mol) obtained from Shin-Etsu Kogyo Co., Ltd. (viscosity: 7.6 mPa·s)

(Other ingredients)

e1: M-130G obtained from Shin-Nakamura Chemical Industry Co., Ltd.

e2: N-hexyl-4-methylpyridinium phosphorus hexafluoride (60% toluene solution)

(2) Preparation of adhesive sheet

Each of the pressure-sensitive adhesive compositions prepared in (1) above was applied to the release-treated surface of a release film made of a release-treated polyethylene terephthalate film [trade name "PLR-382051" obtained from Lintech Co., Ltd.] using an applicator after drying It apply|coated so that thickness might be set to 20 micrometers, and it dried at 100 degreeC for 1 minute, and produced the adhesive layer. On the opposite side to the release film of this pressure-sensitive adhesive layer, the release treatment surface side of the release film similar to the above was laminated to obtain an pressure-sensitive adhesive sheet. Confirmation of a peeling state and the measurement of peeling force were performed using the obtained adhesive sheet. The results are shown in Table 3.

1: optical laminate
2: Polarizer
3: first resin film
4: 2nd resin film
5, 6, 7, 8: optical laminate
10: optical layer
10a: single-sided protection polarizing plate
10b: double-sided protective polarizer
20: adhesive layer
30: conductive layer
40: substrate
50: resin layer.

Claims (13)

a resin, a crosslinking agent and a silane compound;
The silane compound comprises a Si-O-Si bond in the main chain,
Both ends of the main chain of the silane compound have a functional group other than a hydrolyzable group,
The side chain of the silane compound is a pressure-sensitive adhesive composition having a functional group other than a carboxyl group. The pressure-sensitive adhesive composition of claim 1, wherein the silane compound is a leveling agent. The pressure-sensitive adhesive composition according to claim 1 or 2, wherein both ends of the main chain of the silane compound are each independently an alkyl group, a halogenated alkyl group, a phenyl group or an aralkyl group. The pressure-sensitive adhesive composition according to any one of claims 1 to 3, wherein both terminals of the main chain of the silane compound are methyl groups. The pressure-sensitive adhesive composition according to any one of claims 1 to 4, wherein the side chains of the silane compound are each independently an alkyl group or an aralkyl group. The pressure-sensitive adhesive composition according to any one of claims 1 to 5, wherein the silane compound has a viscosity of 300 mPa·s or more at a temperature of 25°C. The pressure-sensitive adhesive composition according to any one of claims 1 to 6, further comprising a silane coupling agent. According to claim 7, wherein the silane coupling agent comprises a siloxane compound comprising a Si-O-Si bond in the main chain,
The siloxane compound is a pressure-sensitive adhesive composition having a hydrolyzable group in the main chain. The pressure-sensitive adhesive composition according to any one of claims 1 to 8, wherein the resin comprises a (meth)acrylic resin. The pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition according to any one of claims 1 to 9. A pressure-sensitive adhesive sheet in which a release film having the same release treatment layer is formed on both surfaces of the pressure-sensitive adhesive layer according to claim 10,
Let the peeling force between the one side of the said adhesive layer and the said release-treated layer side of the said peeling film be a 1st peeling force, and the said release of the said peeling film from the other side of the said adhesive layer on the opposite side to the said one side. When the peeling force between the treatment layers is the second peeling force, the first peeling force and the second peeling force are different from each other. An optical laminate comprising an optical layer and a pressure-sensitive adhesive layer,
The said adhesive layer is an optical laminated body which is the adhesive layer of Claim 10. The optical laminate according to claim 12, wherein the optical layer comprises a polarizing plate.

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