WO2015108063A1

WO2015108063A1 - Adhesive, polarizing film, liquid crystal panel, optical film, and image display device

Info

Publication number: WO2015108063A1
Application number: PCT/JP2015/050770
Authority: WO
Inventors: 建次郎竿本; 武士斉藤; 白男川　美紀; 山崎　達也; 康彰岡田; 池田　哲朗
Original assignee: 日東電工株式会社
Priority date: 2014-01-14
Filing date: 2015-01-14
Publication date: 2015-07-23
Also published as: JP6526972B2; KR20160108330A; CN105899980B; TW201531545A; KR102265481B1; CN105899980A; JP2015155530A; JP2019144593A; TWI667314B; JP6832977B2

Abstract

　Provided is an activation energy beam-curable adhesive having improved water resistance. The adhesive includes an activation energy beam-curable component, and a polyrotaxane, the polyrotaxane having an activation energy beam-polymerizable group. According to one aspect of the invention, the polyrotaxane has a ring-shaped molecule, a linear molecule passing through the opening of the ring-shaped molecule, and capping groups situated at both ends of the linear molecule, so as to prevent detachment of the linear molecule from the ring-shaped molecule. The ring-shaped molecule has the activation energy beam-polymerizable group.

Description

Adhesive, polarizing film, liquid crystal panel, optical film, and image display device

The present invention relates to an adhesive. The adhesive can be used, for example, for laminating polarizing films, various optical films, and liquid crystal cells. The present invention also relates to an image display device including the polarizing film, the various optical films, or the liquid crystal cell.

In a liquid crystal display device which is a typical image display device, polarizers are arranged on both sides of a liquid crystal cell due to the image forming method. The polarizer is usually used in the form of a polarizing film in which a protective film is bonded to at least one surface.

As an adhesive for bonding a protective film to a polarizer, a water-based adhesive (for example, Patent Document 1) obtained by dissolving a polyvinyl alcohol-based material in water or an active energy ray-curable adhesive (for example, Patent Document) 2) has been proposed. According to the active energy ray curable adhesive, compared to a water-based adhesive, a drying step is not required in the bonding of the polarizer and the protective film, and a good adhesiveness is obtained even for a polarizer with a low moisture content. There are advantages such as being obtained.

However, even in a conventional active energy ray-curable adhesive (for example, Patent Document 2), adhesion may be insufficient in a harsh environment such as a hydrolytic environment, and water resistance at a higher level is required. May be.

On the other hand, a pressure-sensitive adhesive composition suitable for an optical member containing a (meth) acrylic acid ester polymer, a crosslinking agent, and a polyrotaxane has been proposed (for example, Patent Document 3). However, in the pressure-sensitive adhesive composition, there is no problem regarding water resistance, and it is considered that the water resistance problem is unlikely to occur in terms of the composition and use.

JP 2005-338343 A JP 2010-78700 A JP 2013-56963 A

The present invention provides an active energy ray-curable adhesive having improved water resistance.

According to the present invention, there is provided an adhesive comprising an active energy ray-curable component and a polyrotaxane, wherein the polyrotaxane has an active energy ray polymerizable group.
In one embodiment, the polyrotaxane includes a cyclic molecule, a linear molecule penetrating through the opening of the cyclic molecule, and the linear molecule so that the cyclic molecule is not detached from the linear molecule. The cyclic molecule has the active energy ray-polymerizable group.
In one embodiment, the active energy ray-curable component has a weight average molecular weight of 20 to 99,000.
In one embodiment, the cyclic molecule further has a hydrophobic modifying group.
In one embodiment, the adhesive contains a hydroxyl group-containing monomer as the active energy ray-curable component.
In one embodiment, the blending amount of the polyrotaxane is 2 to 50 parts by weight with respect to 100 parts by weight of the total of the active energy ray-curable component and the polyrotaxane.
In one embodiment, the polyrotaxane has 2 to 1280 active energy ray polymerizable groups in one molecule.
In one embodiment, the adhesive further includes a photopolymerization initiator.
In one embodiment, the active energy ray-curable component is a radical polymerizable monomer.
In one embodiment, the active energy ray polymerizable group is a radical polymerizable group.
According to another aspect of the present invention, a polarizing film is provided. The polarizing film includes a polarizer and a protective film provided on at least one surface of the polarizer via an adhesive layer. The adhesive layer is formed by the adhesive.
According to another aspect of the present invention, a liquid crystal panel is provided. The liquid crystal panel includes a liquid crystal cell and a polarizer provided on at least one surface of the liquid crystal cell via an adhesive layer. The adhesive layer is formed by the adhesive.
According to another aspect of the present invention, an optical film is provided. The optical film has an adhesive layer formed by the adhesive.
According to another aspect of the present invention, an image display device is provided. The image display device includes the polarizing film or the liquid crystal panel.

According to the present invention, an active energy ray-curable adhesive having improved water resistance can be obtained by blending an active energy ray-curable component and a polyrotaxane having an active energy ray-polymerizable group.

[A. adhesive]
The adhesive of the present invention includes an active energy ray-curable component and a polyrotaxane having an active energy ray polymerizable group. The adhesive of the present invention is of an active energy ray curable type and can be used, for example, in an ultraviolet curable type, an electron beam curable type, or a visible light curable type, and preferably in an ultraviolet curable type. When used in an electron beam curable type, it is not particularly necessary, but when used in an ultraviolet curable type or a visible light curable type, the adhesive of the present invention may further contain a photopolymerization initiator.

[A-1. Active energy ray-curable component]
As the active energy ray-curable component, any suitable curable compound having an active energy ray-polymerizable group can be used. The curing method is not limited and may be a radical polymerization method or a cationic polymerization method. From the viewpoint of compatibility with the polyrotaxane and the variety of material selection, a radical polymerizable monomer having a radical polymerizable group is preferably used. Examples of the radical polymerizable group include a (meth) acryloyl group and a (meth) acryloyloxy group. In the present specification, (meth) acryloyl means methacryloyl and / or acryloyl.

Any appropriate value can be adopted as the weight average molecular weight of the active energy ray-curable component. The weight average molecular weight is, for example, 20 to 99,000 in terms of GPC (Gel Permeation Chromatography), preferably 40 to 10,000, more preferably 60 to 1000, and most preferably 100 to 600.

As the active energy ray-curable component, a hydroxyl group-containing monomer can be preferably used. By using the hydroxyl group-containing monomer, good adhesion to the adherend and good compatibility with the polyrotaxane can be obtained. Specific examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxy acrylate, and 1,4-cyclohexane. Hydroxyalkyl (meth) acrylates such as methanol monoacrylate; N-hydroxyalkyl (meth) acrylamides such as N-hydroxyethyl (meth) acrylamide and N-hydroxymethyl (meth) acrylamide; 2-hydroxy-3-phenoxypropyl (meth) ) Acrylate, 2-hydroxy-3-t-butylphenoxypropyl (meth) acrylate, 2-hydroxy-3-phenylpolyethyleneglycolpropyl (meth) acrylate, etc. (Meth) acrylate having: N- (2,2-dimethoxy-1-hydroxyethyl)-(meth) acrylamide, p-hydroxyphenyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylol-N— Examples include propane (meth) acrylamide. Of these, 4-hydroxybutyl (meth) acrylate and N-hydroxyethyl (meth) acrylamide are preferable. These monomers can be used individually by 1 type or in combination of 2 or more types.

Another preferred active energy ray-curable component is an N-substituted amide monofunctional monomer that does not contain a hydroxyl group. By using the N-substituted amide monomer, good adhesion to the protective film and good compatibility with the polyrotaxane can be obtained. The N-substituted amide monomer is represented by the following general formula (1).
CH ₂ = C (R ¹ ) -CONR ² (R ³ ) (1)
(R ¹ represents a hydrogen atom or a methyl group, and R ² represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms which may have a mercapto group, an amino group or a quaternary ammonium group. R ³ represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, except that R ² and R ³ are simultaneously a hydrogen atom, or R ² and R ³ are And bonded to form a 5- or 6-membered ring which may contain an oxygen atom.)

Examples of the straight-chain or branched-chain alkyl group of the above general formula (1) R ² or R ³ 1 to 4 carbon atoms in, for example, a methyl group, an ethyl group, an isopropyl group, a t- butyl group and the like can be mentioned Examples of the alkyl group having an amino group include an aminomethyl group and an aminoethyl group. Moreover, when R < ² >, R < ³ > couple | bonds together and forms the 5-membered ring or 6-membered ring which may contain an oxygen atom, it may be a heterocyclic ring which has nitrogen. Examples of the heterocyclic ring include morpholine ring, piperidine ring, pyrrolidine ring, piperazine ring and the like.

Specific examples of the N-substituted amide monomer not containing a hydroxyl group include, for example, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, and N-isopropyl. Examples include acrylamide, N-butyl (meth) acrylamide, N-hexyl (meth) acrylamide, aminomethyl (meth) acrylamide, aminoethyl (meth) acrylamide, mercaptomethyl (meth) acrylamide, and mercaptoethyl (meth) acrylamide. Examples of the heterocyclic-containing monomer having a heterocyclic ring include N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, N-acryloylpyrrolidine, N-vinylpyrrolidone (NVP) and the like. These monomers can be used alone or in combination of two or more.

Still another preferable active energy ray-curable component is a polyfunctional monomer such as a hydrocarbon-based or hydrocarbon ether-based polyfunctional monomer. The hydrocarbon-based or hydrocarbon ether-based polyfunctional monomer is a compound in which a hydroxyl group of a polyhydric alcohol having a main skeleton of a hydrocarbon group having 4 to 100 carbon atoms or a hydrocarbon ether group is (meth) acrylated. From the viewpoint of adhesiveness due to crosslinking. Examples of the hydrocarbon group of the polyhydric alcohol include a linear or branched aliphatic hydrocarbon group, an aromatic hydrocarbon group, an alicyclic hydrocarbon group, and a hydrocarbon group obtained by combining these hydrocarbon groups. Examples of the hydrocarbon ether group include those obtained by etherifying these hydrocarbon groups. Examples of the polyhydric alcohol having a hydrocarbon ether group as the main skeleton include compounds obtained by adding an alkylene oxide having 2 to 4 carbon atoms to the polyhydric alcohol (addition number 1 to 30), and alkylene oxides having 2 to 4 carbon atoms. And polyalkylene glycol (addition number 1 to 30) obtained from the above. These monomers can be used alone or in combination of two or more.

Specific examples of the hydrocarbon-based bifunctional monomer include, for example, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) ) Acrylate, neopentyl glycol di (meth) acrylate, 1,9-nonanediol (meth) acrylate and other alkylene glycol di (meth) acrylate; cyclohexane dimethanol di (meth) acrylate, tricyclodecane dimethanol di Di (meth) acrylate of a diol compound having an alicyclic hydrocarbon group such as (meth) acrylate; di (meth) acrylate of a diol compound having an aromatic hydrocarbon group such as bisphenol A di (meth) acrylate It is done.

Specific examples of the hydrocarbon ether-based bifunctional monomer include, for example, alkoxylated hexanediol di (meth) acrylate, alkoxylated cyclohexanedimethanol di (meth) acrylate, alkoxylated di (meth) acrylate, Di (meta) of a compound obtained by adding an alkylene oxide to an alkylene glycol or diol compound described in the above hydrocarbon-based bifunctional monomer such as an alkoxylated neopentyl glycol di (meth) acrylate or alkoxylated bisphenol A di (meth) acrylate. ) Acrylate and the like. Specific examples of the hydrocarbon ether-based bifunctional monomer include diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, Examples include poly (alkylene glycol) di (meth) acrylates such as tripropylene glycol di (meth) acrylate and dipropylene glycol di (meth) acrylate, and dioxane glycol di (meth) acrylate.

Specific examples of the hydrocarbon-based or hydrocarbon ether-based trifunctional monomer and tetrafunctional monomer include, for example, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and glyceryltri (meth). Add alkylene oxide to tri (meth) acrylate or tetra (meth) acrylate of tri- or tetraol compounds such as acrylate, pentaerythritol tetra (meth) acrylate, trimethylolpropane tetra (meth) acrylate, and the above tri- or tetraol compounds And tri (meth) acrylate or tetra (meth) acrylate of the compound obtained.

Still another preferred active energy ray-curable component is a carboxyl group-containing monomer. A carboxyl group-containing monomer is also preferable from the viewpoint of adhesiveness. Examples of the carboxyl group-containing monomer include (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, and the like. Of these, acrylic acid is preferred. These monomers can be used alone or in combination of two or more.

Specific examples of active energy ray-curable components that can be used in addition to the above include bridged ring structures such as dicyclopentanyl groups, dicyclopentenyl groups, adamantyl groups, tricyclopentanyl groups, and tricyclopentenyl groups. (Meth) acrylate having an alicyclic hydrocarbon group; methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) C 1-12 alkyl (meth) acrylates such as acrylate and lauryl (meth) acrylate; (meth) acrylic acid alkoxyalkyl monomers such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; anhydrous Acid anhydrides such as maleic acid and itaconic anhydride Group-containing monomer; caprolactone adduct of acrylic acid; styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, (meta ) Sulfonic acid group-containing monomers such as acryloyloxynaphthalene sulfonic acid; and phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate. (Meth) acrylamide; maleimide, N-cyclohexylmaleimide, N-phenylmaleimide, etc .; aminoethyl (meth) acrylate, aminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate (Meth) acrylic acid alkylaminoalkyl monomers such as (meth) acrylic acid t-butylaminoethyl, 3- (3-pyridinyl) propyl (meth) acrylate; N- (meth) acryloyloxymethylene succinimide and N- ( And nitrogen-containing monomers such as succinimide monomers such as (meth) acryloyl-6-oxyhexamethylenesuccinimide and N- (meth) acryloyl-8-oxyoctamethylenesuccinimide;

In a preferred embodiment, a hydroxyl group-containing monomer and an N-substituted amide monomer and / or polyfunctional monomer that do not contain a hydroxyl group are used in combination.

The ratio of the hydroxyl group-containing monomer to the total active energy ray-curable component contained in the adhesive is, for example, 5 wt% to 70 wt%, preferably 30 wt% to 70 wt%, more preferably 35 wt% to 60 wt%. is there.

The ratio of the N-substituted amide monomer not containing a hydroxyl group to the total active energy ray-curable component contained in the adhesive is, for example, 0% by weight to 70% by weight, preferably 30% by weight to 70% by weight, and more preferably 35%. % By weight to 60% by weight.

The ratio of the polyfunctional monomer to the total active energy ray-curable component contained in the adhesive is, for example, 0 wt% to 70 wt%, preferably 30 wt% to 70 wt%, more preferably 35 wt% to 60 wt%. is there.

[A-2. Polyrotaxane]
The polyrotaxane includes a cyclic molecule, a linear molecule penetrating through the opening of the cyclic molecule, and a blockade disposed at both ends of the linear molecule so that the cyclic molecule is not detached from the linear molecule. And a group.

The cyclic molecule is not particularly limited as long as it is a molecule in which a linear molecule is included in a skewered manner in the opening and is movable on the linear molecule and has an active energy ray polymerizable group. In the present specification, “cyclic” of “cyclic molecule” means substantially “cyclic”. That is, the cyclic molecule may not be completely closed as long as it can move on the linear molecule.

Specific examples of the cyclic molecule preferably include cyclic polymers such as cyclic polyether, cyclic polyester, cyclic polyetheramine, and cyclic polyamine, and cyclodextrins such as α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin. It is done. Of these, cyclodextrins such as α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin are preferred because they are relatively easily available and many types of blocking groups can be selected. Two or more cyclic molecules may be mixed in the polyrotaxane or in the adhesive.

In the polyrotaxane used in the present invention, the cyclic molecule has an active energy ray polymerizable group. Thereby, since the polyrotaxane and the active energy ray-curable component react with each other and an adhesive having a movable crosslinking point even after curing can be obtained, the water resistance of the adhesive is improved. The active energy ray polymerizable group of the cyclic molecule may be any group that can be polymerized with the active energy ray curable compound, and examples thereof include a radical polymerizable group and a cationic polymerizable functional group. Examples of the radical polymerizable group include a (meth) acryloyloxy group and a (meth) acryloyl group, a (meth) acryloyloxy group is preferable, and an acryloyloxy group is more preferable. By adopting the above chemical group as the radical polymerizable group, a high curing rate can be achieved. As a result, not only high productivity can be obtained, but also higher water resistance can be imparted. Examples of the cationic polymerizable functional group include an epoxy group and a vinyl ether group.

When cyclodextrin is used as the cyclic molecule, the active energy ray-polymerizable group is preferably any suitable linker (for example, a structure represented by formula (I) or formula (II) described later) on the hydroxyl group of cyclodextrin. Is introduced through. The number of the active energy ray-polymerizable groups in the molecule of the polyrotaxane is preferably 2 to 1280, more preferably 100 to 1100, still more preferably 500 to 1000. Since the polyrotaxane has more than a predetermined number of active energy ray-polymerizable groups in one molecule, more crosslinking points after curing can be secured, thereby improving the effect of imparting water resistance.

It is preferable that a hydrophobic modifying group is introduced into the cyclic molecule. By introducing the hydrophobic modifying group, the compatibility with the active energy ray-curable component can be improved. Further, since hydrophobicity is imparted, when used as an adhesive, water can be prevented from entering the interface between the adhesive layer and the adherend, and the water resistance can be further improved. Examples of the hydrophobic modifying group include a polyester chain, a polyamide chain, an alkyl chain, an oxyalkylene chain, and an ether chain. Specific examples include groups described in [0027] to [0042] of WO2009 / 145073. A preferred hydrophobic modifying group may have, for example, a structure represented by the following formula (I) or formula (II).

In the structure represented by formula (I) or formula (II), Q in each repeating unit may be the same or different. When Q is different (ie, when the structure is a copolymer), the form can be any form such as a random copolymer, block copolymer, alternating copolymer, and the like.

In the formula, Q is a linear alkylene group or alkenylene group having 1 to 8 carbon atoms, a branched alkylene group or alkenylene group having 3 to 20 carbon atoms, and a part of the alkylene group or alkenylene group is —O— bond. Or at least one selected from the group consisting of a hydroxyl group, a carboxyl group, an acyl group, a phenyl group, a halogen atom, and an olefin group, wherein the alkylene group substituted with an —NH— bond, or a part of hydrogen of the alkylene group is A substituted alkylene group, preferably a linear alkylene group having 3 to 8 carbon atoms, a branched alkylene group having 5 to 10 carbon atoms, more preferably a linear alkylene group having 4 to 6 carbon atoms. is there.

N1 and n2 are each independently 1 to 200, preferably 2 to 100, more preferably 3 to 50.

The structure represented by the above formula (I) and the structure represented by the formula (II) are preferably derived from ring-opening polymerization of a lactone monomer and / or a lactam monomer. Examples of lactone monomers include 4-membered ring lactones such as β-propiolactone, β-methylpropiolactone, and L-serine-β-lactone derivatives; γ-butyrolactone, γ-hexanolactone, and γ-heptanolactone. , Γ-octanolactone, γ-decanolactone, γ-dodecanolactone, α-hexyl-γ-butyrolactone, α-heptyl-γ-butyrolactone, α-hydroxy-γ-butyrolactone, γ-methyl-γ-decanolactone, α -Methylene-γ-butyrolactone, α, α-dimethyl-γ-butyrolactone, D-erythronolactone, α-methyl-γ-butyrolactone, γ-nonanolactone, DL-pantolactone, γ-phenylγ-butyrolactone, γ-unde Canolactone, γ-valerolactone, 2,2-pentamethylene-1,3-dioxola 5-membered rings such as N-4-one, α-bromo-γ-butyrolactone, γ-crotonolactone, α-methylene-γ-butyrolactone, α-methacryloyloxy-γ-butyrolactone, β-methacryloyloxy-γ-butyrolactone, etc. Lactone: δ-valerolactone, δ-hexanolactone, δ-octanolactone, δ-nonanolactone, δ-decanolactone, δ-undecanolactone, δ-dodecanolactone, δ-tridecanolactone, δ-tetradecano Examples thereof include 6-membered ring lactones such as lactone, DL-mevalonolactone and 4-hydroxy-1-cyclohexanecarboxylic acid δ-lactone; 7-membered ring lactones such as ε-caprolactone; lactide and 1,5-dioxepan-2-one. Of these, ε-caprolactone, γ-butyllactone, α-methyl-γ-butyllactone, δ-valerolactone, and lactide are preferable, and ε-caprolactone is more preferable.

Examples of lactam monomers include 4-membered lactams such as 4-benzoyloxy-2-azetidinone; γ-butyrolactam, 2-azabicyclo [2.2.1] hept-5-en-3-one, 5-methyl- 5-membered lactams such as 2-pyrrolidone; 6-membered lactams such as ethyl 2-piperidone-3-carboxylate, 7-membered lactams such as ε-caprolactam, DL-α-amino-ε-caprolactam; ω-heptalactam Is mentioned. Of these, ε-caprolactam, γ-butyrolactam, and DL-α-amino-ε-caprolactam are preferable, and ε-caprolactam is more preferable.

Specific examples of preferred hydrophobic modifying groups include groups represented by the following formula (III).
-LMA (Formula III)
In formula (III), L is a single bond or any suitable linker, M is a structure represented by formula (I) or formula (II), and A is —OH or —OC (═ O) HNH (CH ₂ ) _n3 X (X is a (meth) acryloyl group, and n3 is a linear or branched alkylene group having 1 to 8 carbon atoms). The linker may be, for example, a linear or branched alkylene group having 1 to 8 carbon atoms.

When cyclodextrin is used as the cyclic molecule, the hydrophobic modifying group is typically introduced into the hydroxyl group of cyclodextrin. The introduction rate (degree of substitution) of the hydrophobic modifying group into the hydroxyl group is preferably 10% to 90%, more preferably 20% to 80%, and still more preferably 30% to 70%. The polyrotaxane may have the same hydrophobic modifying group in the molecule, and has different hydrophobic modifying groups (for example, both a group in which A is a hydroxyl group and a group containing a (meth) acryloyl group). May be.

As a linear molecule, a molecule or substance that is included in a cyclic molecule and can be integrated by a mechanical bond rather than a chemical bond such as a covalent bond, It is not limited. In the present specification, “linear” of “linear molecule” means substantially “linear”. That is, the linear molecule may have a branched chain as long as the cyclic molecule can move on the linear molecule.

As the linear molecule, for example, polyethylene glycol, polypropylene glycol, polyisoprene, polyisobutylene, polybutadiene, polytetrahydrofuran, polyacrylic acid ester, polydimethylsiloxane, polyethylene, polypropylene and the like are preferable. Two or more kinds of linear molecules may be mixed in the adhesive.

The number average molecular weight of the linear molecule is preferably from 3,000 to 300,000, more preferably from 10,000 to 200,000, and even more preferably from 20,000 to 100,000. . If the number average molecular weight is less than 3,000, the amount of movement of the cyclic molecule on the linear molecule becomes small, and sufficient flexibility cannot be imparted to the adhesive, and the adhesion between the adherend and the adhesive. There is a possibility that the effect of improving the water resistance cannot be obtained sufficiently due to the absence of. Moreover, when a number average molecular weight exceeds 300,000, there exists a possibility that compatibility with an active energy ray hardening component may fall.

The blocking group is not particularly limited as long as the cyclic molecule is a group capable of maintaining a form in which the cyclic molecule is skewered with a linear molecule. Examples of such groups include dinitrophenyl groups, cyclodextrins, adamantane groups, trityl groups, fluoresceins, pyrenes, anthracene, and the like, or a high number average molecular weight of 1,000 to 1,000,000. Examples include the main chain or side chain of the molecule. Two or more blocking groups may be mixed in the polyrotaxane or the adhesive.

In the polyrotaxane, when the cyclic molecule is clasped with a linear molecule in a skewered manner, the cyclic molecule is preferably They are skewered into linear molecules in an amount of 0.1% to 60%, more preferably 1% to 50%, and even more preferably 5% to 40%. The maximum inclusion amount of the cyclic molecule can be determined by the length of the linear molecule and the thickness of the cyclic molecule. For example, when the linear molecule is polyethylene glycol and the cyclic molecule is an α-cyclodextrin molecule, the maximum inclusion amount is experimentally determined (see Macromolecules 1993, 26, 5698-5703).

The polyrotaxane can be obtained, for example, by the methods described in JP-A-2005-154675, JP-A-2009-270119, WO2009 / 145073, and the like. Commercial products (for example, “Celum Super Polymer” series manufactured by Advanced Soft Materials) can also be purchased.

The lower limit of the blending amount of the polyrotaxane in the adhesive of the present invention is preferably 2 parts by weight, for example, 3 parts by weight with respect to 100 parts by weight of the total curable component (total of the active energy ray curable component and the polyrotaxane). Parts, 4 parts by weight, 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight or 10 parts by weight. On the other hand, the upper limit is preferably 50 parts by weight, more preferably 40 parts by weight, still more preferably 30 parts by weight. If the blending amount is less than 2 parts by weight, the effect of improving water resistance may be insufficient. Moreover, when a compounding quantity exceeds 50 weight part, adhesive force or transparency may fall.

[A-3. Photopolymerization initiator]
Any appropriate photopolymerization initiator is used as the photopolymerization initiator. Specific examples of the photopolymerization initiator include 2,2-dimethoxy-2-phenylacetophenone, acetophenone, benzophenone, xanthone, 3-methylacetophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, benzoin propyl ether, benzyl Dimethyl ketal, N, N, N ′, N′-tetramethyl-4,4′-diaminobenzophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, thioxanthone compounds, etc. Is mentioned.

The blending amount of the photopolymerization initiator is usually about 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the total curable components (active energy ray-curable component and polyrotaxane). More preferably, it is 1 to 4 parts by weight.

[A-4. Additive]
The adhesive of the present invention may further contain any appropriate additive. Specific examples of additives include sensitizers that increase the curing speed and sensitivity of active energy rays typified by carbonyl compounds, adhesion promoters typified by silane coupling agents and ethylene oxide, and wettability with adherends. Additives, acryloxy group compounds and hydrocarbons (natural, synthetic resins), etc., which improve mechanical strength and processability, UV absorbers, anti-aging agents, dyes, processing aids , Ion trapping agents, antioxidants, tackifiers, fillers, metal compound fillers, plasticizers, leveling agents, foaming inhibitors, antistatic cracks, and the like.

[B. Polarized film]
The polarizing film of the present invention includes a polarizer and a protective film provided on at least one surface of the polarizer via an adhesive layer.

[B-1. Polarizer]
Any appropriate polarizer can be adopted as the polarizer. Specific examples include hydrophilic polymer films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and ethylene / vinyl acetate copolymer partially saponified films, and dichroic substances such as iodine and dichroic dyes. Examples thereof include polyene-based oriented films such as those subjected to the dyeing treatment and stretching treatment according to the above, polyvinyl alcohol dehydrated products and polyvinyl chloride dehydrochlorinated products. Preferably, a polarizer obtained by dyeing a polyvinyl alcohol film with iodine and uniaxially stretching is used because of excellent optical properties.

The dyeing with iodine is performed, for example, by immersing a polyvinyl alcohol film in an aqueous iodine solution. The stretching ratio of the uniaxial stretching is preferably 3 to 7 times. The stretching may be performed after the dyeing treatment or may be performed while dyeing. Moreover, you may dye | stain after extending | stretching. If necessary, the polyvinyl alcohol film is subjected to swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like. For example, by immersing a polyvinyl alcohol film in water and washing it before dyeing, not only can the surface of the polyvinyl alcohol film be cleaned and anti-blocking agents can be washed, but the polyvinyl alcohol film can be swollen and dyed. Unevenness and the like can be prevented.

The thickness of the polarizer is typically about 1 μm to 80 μm, preferably 3 μm to 30 μm, more preferably 5 μm to 10 μm.

The polarizer may have a moisture content of 20% by weight or less, and may have a moisture content of, for example, 0 to 15% by weight, for example, 1 to 10% by weight. When the moisture content of the polarizer is 20% by weight or less, it is possible to obtain a polarizing film in which the dimensional change under high temperature or high temperature and high humidity is suppressed.

The moisture content of the polarizer is measured by the following method. That is, the polarizer is cut into a size of 100 × 100 mm, and the initial weight of this sample is measured. Subsequently, this sample is dried at 120 ° C. for 2 hours, the dry weight is measured, and the moisture content is measured by the following formula. Each weight is measured three times, and the average value is used.
Moisture content (% by weight) = {(initial weight−dry weight) / initial weight} × 100

[B-2. Protective film]
As the protective film, any appropriate film that can be used as a protective layer of a polarizer can be adopted. An isotropic film may be sufficient and a film which has a phase difference and is equipped with an optical compensation function may be sufficient. Examples of the material for forming the protective film include (meth) acrylic resins, cellulose resins such as diacetyl cellulose and triacetyl cellulose, cycloolefin resins, olefin resins such as polypropylene, and ester resins such as polyethylene terephthalate resins. , Polyamide resins, polycarbonate resins, copolymer resins thereof, and the like. When providing protective films on both sides of the polarizer, protective films made of the same material may be used on both sides, or protective films made of different materials may be used.

The thickness of the protective film is preferably 1 μm to 300 μm, more preferably 3 μm to 100 μm, still more preferably 5 μm to 40 μm.

The protective film is laminated on at least one surface of the polarizer via an adhesive layer. The adhesive layer is formed by the adhesive described in the above section A. The thickness of the adhesive layer is preferably 0.01 μm to 7 μm, more preferably 0.1 μm to 5 μm, and still more preferably 0.5 μm to 3 μm.

[B-3. Manufacturing method of polarizing film]
The polarizing film of the present invention is, for example, a method in which an adhesive is applied to the surface on the side where the protective film of the polarizer is provided or the surface on the side where the polarizer of the protective film is provided, and the polarizer is applied via an adhesive coating layer. And a protective film are bonded together to obtain a laminate, and the obtained laminate is irradiated with an active energy ray to cure the adhesive to form an adhesive layer.

Each of the polarizer and the protective film may be subjected to a surface modification treatment before applying the adhesive. Specific examples of the treatment include corona treatment, plasma treatment, and saponification treatment.

The adhesive application method is appropriately selected depending on the viscosity of the adhesive and the desired thickness. For example, a reverse coater, a gravure coater (direct, reverse or offset), a bar reverse coater, a roll coater, a die coater, a bar coater, a rod coater and the like can be mentioned. In addition, a coating method such as a dipping method can be appropriately used.

The lamination of the polarizer and the protective film can be performed by a roll laminator or the like.

Activating energy rays can be irradiated from any appropriate direction. Preferably, it irradiates from the protective film side. When irradiated from the polarizer side, the polarizer may be degraded by active energy rays.

As the irradiation condition of the active energy ray, any appropriate condition can be adopted as long as the adhesive can be cured. For example, in the electron beam irradiation, the acceleration voltage is preferably 5 kV to 300 kV, more preferably 10 kV to 250 kV. The irradiation dose is 5 to 100 kGy, more preferably 10 to 75 kGy. On the other hand, the irradiation amount of ultraviolet rays is preferably integrated quantity of light 380 ~ 430 nm is 50 ~ 3000mJ / cm ^2, more preferably 100 ~ 2000mJ / cm ^2.

[C. LCD panel]
The liquid crystal panel of the present invention includes a liquid crystal cell and a polarizer provided on at least one surface of the liquid crystal cell via an adhesive layer. Needless to say, the polarizer may be provided only on one side of the liquid crystal cell or on both sides of the liquid crystal cell.

[C-1. Polarizer]
Any appropriate polarizer can be adopted as the polarizer. Specific examples include the polarizers described in Section B-1.

[C-2. Liquid crystal cell]
Any appropriate liquid crystal cell can be adopted as the liquid crystal cell. Specific examples include twisted nematic (TN) mode, super twisted nematic (STN) mode, horizontal alignment (ECB) mode, vertical alignment (VA) mode, in-plane switching (IPS) mode, bend nematic (OCB) mode, strong Examples thereof include dielectric liquid crystal (SSFLC) mode and antiferroelectric liquid crystal (AFLC) mode liquid crystal cells. The general configuration of the liquid crystal panel is well known in the industry, and detailed description thereof is omitted.

[D. Optical film]
According to another aspect of the present invention, an optical film is provided. The optical film has an adhesive layer formed by the adhesive. Any appropriate optical film can be adopted as the optical film. As said optical film, the film which has an optical function used for an image display apparatus etc. is mentioned, for example. More specifically, examples include a retardation film, a surface treatment film, and a separator film. The surface treatment film may have a hard coat layer and / or an antiglare layer. As said separator film, the separator film aiming at the surface protection until use is mentioned, for example.

[E. Image display device]
The image display device of the present invention includes the polarizing film described in Item B, the liquid crystal panel described in Item C, or the optical film described in Item D. The image display device of the present invention may be a liquid crystal display (LCD), an electroluminescence display (ELD) or the like.

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. In Examples, unless otherwise specified, “parts” and “%” are based on weight.

[Production Example 1 Polarizer]
A polyvinyl alcohol film having an average polymerization degree of 2400, a saponification degree of 99.9 mol%, and a thickness of 75 μm was immersed in warm water at 30 ° C. for 60 seconds to swell. Subsequently, the film was stretched to 3.5 times while dyeing in an iodine solution of 0.3 wt% (weight ratio: iodine / potassium iodide = 0.5 / 8) at 30 ° C. for 1 minute. Thereafter, the total draw ratio was stretched to 6 times while being immersed in a 4% by weight boric acid aqueous solution at 65 ° C. for 0.5 minutes. After stretching, drying was performed in an oven at 70 ° C. for 3 minutes to obtain a polarizer having a thickness of 26 μm. The moisture content of the polarizer was 13.5% by weight.

[Production Example 2 protective film]
A triacetyl cellulose film (manufactured by Konica Minolta, trade name “KC4UY”, thickness 40 μm) was used.

[Example 1]
40.0 parts of hydroxyethyl acrylamide (HEAA, manufactured by Kojin Co., Ltd.), 50.0 parts of acryloylmorpholine (ACMO, manufactured by Kojin Co., Ltd.), polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SA3405P” ”, Linear molecule: PEG, cyclic molecule: α-cyclodextrin, the introduction ratio of the polycaprolactone chain to the total hydroxyl groups on the cyclic molecule is 50 to 60%, and about 70% of the introduced polycaprolactone chain 10.0 parts is a polycaprolactone chain containing acryloyl group), 1.5 parts product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) as a photoinitiator and “IRGACURE907” (manufactured by BASF Japan) 1.5 parts) was mixed to prepare an adhesive.

On the protective film of Production Example 2, the adhesive was applied to a thickness of 1 μm using a micro gravure coater (gravure roll: # 700, rotational speed 140% / line speed). A protective film with a coating layer was obtained. Subsequently, the protective film with a coating layer of an adhesive was bonded to both surfaces of the polarizer of Production Example 1 with a roll machine. Adhesive by irradiating active energy rays with an integrated light quantity of 1000 mJ / cm ^{2 with} a metal halide lamp from the protective film side (both sides) of the obtained laminate (protective film / coating layer / polarizer / coating layer / protective film). Was cured to obtain a polarizing film.

[Example 2]
4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Co., Ltd.) 35.0 parts and 1,9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 And 25.0 parts of polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SA3405P”), and product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) 1.5 as a photoinitiator. Part and product name “IRGACURE907” (manufactured by BASF Japan Ltd.) 1.5 parts were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Example 3]
4-Hydroxybutyl acrylate (4HBA, Osaka Organic Chemical Co., Ltd.) 35.0 parts, acryloylmorpholine (ACMO, Kojin Co., Ltd.) 35.0 parts, polyrotaxane (Advanced Soft Materials, product name “ "Serum Superpolymer SA3405P") 30.0 parts, 1.5 parts of the product name "KAYACURE DETX-S" (manufactured by Nippon Kayaku Co., Ltd.) and 1.5 "IRGACURE907" (manufactured by BASF Japan) as the photoinitiator Were mixed with each other to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Example 4]
40.0 parts of 4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Industry Co., Ltd.), 58.0 parts of dicyclopentenyl acrylate (manufactured by Hitachi Chemical Co., Ltd., product name “Fancryl FA-511AS”), polyrotaxane (Advanced・ Soft Materials Co., Ltd., product name “Celum Superpolymer SA3405P”) 2.0 parts, photoinitiator product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) and product name “IRGACURE907” "(1.5% by BASF Japan) was mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Example 5]
4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Co., Ltd.) 35.0 parts and 1,9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 25.0 parts of polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SA2405P”), and product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) 1.5 as a photoinitiator. Part and product name “IRGACURE907” (manufactured by BASF Japan Ltd.) 1.5 parts were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Example 6]
4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Co., Ltd.) 35.0 parts and 1,9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 And 25.0 parts of polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SA1315P”), and product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) 1.5 as a photoinitiator. Part and product name “IRGACURE907” (manufactured by BASF Japan Ltd.) 1.5 parts were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Example 7]
4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Co., Ltd.) 35.0 parts and 1,9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 And 25.0 parts of polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SM3405P”), and product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) 1.5 as a photoinitiator. Part and product name “IRGACURE907” (manufactured by BASF Japan Ltd.) 1.5 parts were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Example 8]
4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Co., Ltd.) 35.0 parts and 1,9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 And 25.0 parts of polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SM1315P”), and product name “KAYACURE DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) 1.5 as a photoinitiator. Part and product name “IRGACURE907” (manufactured by BASF Japan Ltd.) 1.5 parts were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Comparative Example 1]
50.0 parts of hydroxyethylacrylamide (HEAA, manufactured by Kojin Co., Ltd.), 50.0 parts of acryloylmorpholine (ACMO, manufactured by Kojin Co., Ltd.), and a product name “KAYACURE DETX-S” (Nippon Kayaku Co., Ltd.) as a photoinitiator 1.5 parts) and a product name “IRGACURE907” (BASF Japan) 1.5 parts were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Comparative Example 2]
40.0 parts of 4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Industry Co., Ltd.) and 1.9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 Parts, 20.0 parts of polypropylene glycol diacrylate (product name “Aronix M-220” manufactured by Toa Gosei Co., Ltd., average polymerization degree ≈3), and product name “KAYACURE DETX-S” (Nippon Kayaku Co., Ltd.) as a photoinitiator 1.5 parts by product) and 1.5 parts by product name “IRGACURE907” (manufactured by BASF Japan) were mixed to prepare an adhesive. A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

[Comparative Example 3]
4-hydroxybutyl acrylate (4HBA, manufactured by Osaka Organic Chemical Co., Ltd.) 35.0 parts and 1,9-nonanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate 1,9ND-A”) 40.0 Part, 25.0 parts of polyrotaxane (manufactured by Advanced Soft Materials, product name “Celum Superpolymer SH3400P” linear molecule: PEG, cyclic molecule: α-cyclodextrin), and product name “KAYACURE as a photoinitiator” An adhesive was prepared by mixing 1.5 parts of “DETX-S” (manufactured by Nippon Kayaku Co., Ltd.) and 1.5 parts of the product name “IRGACURE907” (manufactured by BASF Japan). A polarizing film was obtained in the same manner as in Example 1 except that the adhesive thus obtained was used.

The polarizing film obtained in Examples and Comparative Examples was evaluated for water resistance. The evaluation results are shown in Table 1 together with the composition of the adhesive.
<Water resistance evaluation (1)>
The obtained polarizing plate was cut into a size of 25 mm × 150 mm to obtain a sample. After immersing the sample in warm water at 60 ° C. for 6 hours, the amount of peeling (mm) from the end of the polarizing plate was measured. The amount of peeling is preferably 10 mm or less.
<Water resistance evaluation (2)>
The obtained polarizing film was cut into a size of 100 mm × 15 mm to obtain a sample. The sample was immersed in water at 25 ° C. for 3 hours, and the sample was pulled up from the water. Thereafter, the end of the sample was scratched with hands and nails to examine whether the protective film was peeled off from the polarizer. The examination results were evaluated according to the following criteria.
<Standard>
◎: The protective film could not be peeled off with hands or nails ○: The edge of the protective film could be peeled off with hands or nails, but the center could not be peeled off ×: The protective film could be easily peeled off with hands or nails did it

As shown in Table 1, the polarizing films of Examples 1 to 8 produced using an adhesive containing a polyrotaxane containing an active energy ray polymerizable group were excellent in water resistance. On the other hand, the polarizing films of Comparative Examples 1 and 2 produced using an adhesive not containing polyrotaxane had insufficient water resistance. Furthermore, the polarizing film of Comparative Example 3 produced using an adhesive containing a polyrotaxane containing no active energy ray polymerizable group had insufficient water resistance. The reason why the water resistance of the polarizing film is improved by adding a polyrotaxane containing an active energy ray polymerizable group is not clear, but is presumed as follows. That is, the ability of the crosslinking point to move due to the mobility of the cyclic molecules of polyrotaxane (so-called pulley effect) gives the cured adhesive flexibility and increases the adhesion of the polarizer to the surface irregularities. As a result, it is considered that water has been prevented from entering the interface between the polarizer and the adhesive layer. Furthermore, it is considered that the addition of hydrophobicity to the adhesive due to the polyrotaxane having a hydrophobic modifying group also contributed to preventing water from entering the interface between the polarizer and the adhesive layer.

The adhesive of the present invention can be particularly suitably used for laminating polarizing films, various optical films, and liquid crystal cells.

Claims

An active energy ray-curable component and a polyrotaxane,
An adhesive in which the polyrotaxane has an active energy ray polymerizable group.
The polyrotaxane is a cyclic molecule, a linear molecule penetrating through the opening of the cyclic molecule, and a blockade disposed at both ends of the linear molecule so that the cyclic molecule is not detached from the linear molecule. The adhesive according to claim 1, wherein the cyclic molecule has the active energy ray polymerizable group.
The adhesive according to claim 1 or 2, wherein the active energy ray-curable component has a weight average molecular weight of 20 to 99,000.
The adhesive according to claim 2, wherein the cyclic molecule further has a hydrophobic modifying group.
The adhesive according to any one of claims 1 to 4, comprising a hydroxyl group-containing monomer as the active energy ray-curable component.
6. The adhesive according to claim 1, wherein the amount of the polyrotaxane is 2 to 50 parts by weight with respect to a total of 100 parts by weight of the active energy ray-curable component and the polyrotaxane.
The adhesive according to any one of claims 1 to 6, wherein the polyrotaxane has 2 to 1280 active energy ray polymerizable groups in one molecule.
The adhesive according to any one of claims 1 to 7, further comprising a photopolymerization initiator.
The adhesive according to any one of claims 1 to 8, wherein the active energy ray-curable component is a radical polymerizable monomer.
The adhesive according to any one of claims 1 to 9, wherein the active energy ray polymerizable group is a radical polymerizable group.
11. A polarizing film comprising a polarizer and a protective film provided on at least one surface of the polarizer via an adhesive layer, wherein the adhesive layer is the adhesive according to claim 1. A polarizing film formed by:
A liquid crystal panel comprising: a liquid crystal cell; and a polarizer provided on at least one surface of the liquid crystal cell via an adhesive layer, wherein the adhesive layer is the adhesive according to claim 1. The liquid crystal panel that is formed by.
An optical film having an adhesive layer formed by the adhesive according to any one of claims 1 to 10.
An image display device comprising the polarizing film according to claim 11, the liquid crystal panel according to claim 12, or the optical film according to claim 13.