KR20100059705A - Adhesive composition and optical member using the same - Google Patents

Abstract

PURPOSE: An adhesive composition and an optical member using thereof are provided to improve the heat resistance and flexibility of the composition, and to obtain the excellent re-working property and anti light leakage property when applying the composition to a polarizer. CONSTITUTION: An adhesive composition contains a hydroxy group containing (meth)acrylic polymer(A), an isocyanate hardener(B), and polycarbonate diol(C). The hydroxy group containing (meth)acrylic polymer is formed by polymerizing 99.5~80 parts of (meth)acrylic polymer by mass, 0.5~10 parts of hydroxy group containing (meth)acrylate monomer by mass, and 0~10 parts of other monomers by mass capable of copolymerizing with the (meth)acrylic polymer and the hydroxy group containing (meth)acrylate monomer.

Description

Adhesive composition and optical member using the same TECHNICAL FIELD

The present invention relates to an adhesive composition and an optical member using the same. In more detail, this invention relates to the adhesive composition excellent in heat resistance and flexibility, and the optical member using the same.

In recent years, the use of flat panel displays (FPD), such as liquid crystal display (LCD), plasma display (PDP), and organic EL device, has been expanding. According to this, improvement of the heat resistance and rework property (repeelability) of the adhesive used for FPD is calculated | required. Moreover, when an adhesive is used for LCD, the characteristic as said, preventing light leakage by shrinkage | contraction of a polarizing plate has also been calculated | required.

Here, Patent Document 1 discloses a pressure-sensitive adhesive composition obtained by mixing an isocyanate compound, a polyol compound, and a silane compound having an epoxy group in an acrylic resin.

[Patent Document 1] Japanese Patent No. 3846912.

However, the pressure-sensitive adhesive composition described in Patent Literature 1 has a problem that the crosslinking of the polymer contained is insufficient when the amount of the curing agent is insufficient, and that the heat resistance deteriorates. When the curing agent is large, the crosslinked structure is rigid. There was a problem of lack of flexibility and poor light leakage and rework resistance.

This invention is made | formed in view of the said situation, The objective is to provide the adhesive composition excellent in heat resistance and flexibility.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched in order to solve said problem. As a result, it discovered that the adhesive composition containing the (meth) acrylic-type polymer which has a hydroxyl group, and polycarbonate diol expresses excellent heat resistance and flexibility, and came to complete this invention.

That is, this invention is 99.5-80 mass parts of (a-1) (meth) acrylate type monomers, 0.5-10 mass parts of (a-2) hydroxyl-containing (meth) acrylic-type monomers, and (a-3) said A hydroxyl group formed by polymerizing 0 to 10 parts by mass of other monomers copolymerizable with (a-1) and (a-2) (wherein the total amount of (a-1) to (a-3) is 100 parts by mass). It is an adhesive composition containing a containing (meth) acrylic-type polymer (A), an isocyanate-type hardening | curing agent (B), and a polycarbonate diol (C).

The pressure-sensitive adhesive composition of the present invention is excellent in heat resistance and flexibility. Therefore, the adhesive composition of this invention is effective for adhesion | attachment of to-be-adhered bodies, such as various plastic films, and especially when used for a polarizing plate, the outstanding light leakage resistance and rework resistance can be obtained.

The present invention is (a-1) 99.5 to 80 parts by mass of the (meth) acrylate monomer, (a-2) 0.5 to 10 parts by mass of the hydroxy group-containing (meth) acrylic monomer and (a-3) the above (a -1) and hydroxy group-containing polymerized by polymerizing 0-10 parts by mass of other monomers copolymerizable with (a-2) (wherein the total amount of (a-1) to (a-3) is 100 parts by mass). It is an adhesive composition containing a meta) acrylic-type polymer (A), an isocyanate-type hardening | curing agent (B), and a polycarbonate diol (C).

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the crosslinked structure of the conventional adhesive composition containing the acrylic resin 1, the isocyanate-type hardener (2), and the polyol (3) represented by patent document 1. As shown in FIG. 1, the isocyanate-based curing agent 2 reacts preferentially with the polyol 3 and hardly reacts with the acrylic resin 1. Therefore, when there is little isocyanate-type hardening | curing agent 2, crosslinking of acrylic resin 1 does not advance and there exists a problem that heat resistance falls. Moreover, when there are many isocyanate-type hardening | curing agents 2, since crosslinking of the polyol 3 and the isocyanate-type hardening | curing agent 2 advances excessively, there exists a possibility that an adhesive itself may gelatinize. Moreover, since the crosslinked structure was rigid, there existed a problem that cohesion force of an adhesive became high, but lacked flexibility, and bad light leakage resistance.

On the other hand, FIG. 2 is a schematic diagram which shows the crosslinked structure of the adhesive composition of this invention. As for the adhesive composition of this invention, as shown in FIG. 2, an isocyanate-type hardening | curing agent (B) is a hydroxyl group and polycarbonate diol (C) in a hydroxyl-group containing (meth) acrylic-type polymer (A), and It reacts and bonds and forms a crosslinked structure. Therefore, since the polycarbonate diol (C) is introduced in the crosslinked structure to increase the molecular weight between the crosslinking points, the pressure-sensitive adhesive composition of the present invention has excellent heat resistance and flexibility. By such heat resistance and flexibility, the pressure-sensitive adhesive composition of the present invention can also follow shrinkage of the polarizing plate, and can prevent peeling or lifting of the polarizing plate from the liquid crystal cell substrate even under high temperature and wet heat environment. As described above, the adhesiveness is also excellent. In particular, when used for a polarizing plate, it is excellent in light leakage resistance and rework resistance.

Hereinafter, each component of the adhesive composition of this invention is demonstrated in detail. In addition, in this specification, "(meth) acrylate" is a generic term of acrylate and methacrylate. Similarly, the compound containing (meth), such as (meth) acrylic acid, is also a general term for the compound which has "meta" in a name, and the compound which does not have "meta".

(A) Hydroxyl group  contain ( Meta Acrylic Polymer

The (A) hydroxyl group containing (meth) acrylic-type polymer (henceforth only called a "component (A)") used by this invention is a (a-1) (meth) acrylate-type monomer, (a-2) It is made by copolymerizing a hydroxyl-containing (meth) acrylic monomer and (a-3) (a-1) and the other monomer which can be copolymerized with said (a-2).

(a-1) A (meth) acrylate type monomer (henceforth only called "component (a-1)") is ester of (meth) acrylic acid which does not have a hydroxyl group in a molecule | numerator. As a specific example of a component (a-1), for example, methyl (meth) acrylate,

Ethyl (meth) acrylate, propyl (meth) acrylate,

Isopropyl (meth) acrylate, n-butyl (meth) acrylate,

Isobutyl (meth) acrylate, tert-butyl (meth) acrylate,

Isoamyl (meth) acrylate, n-hexyl (meth) acrylate,

n-heptyl (meth) acrylate, n-octyl (meth) acrylate,

tert-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,

Decyl (meth) acrylate, isodecyl (meth) acrylate,

Tridecyl (meth) acrylate, stearyl (meth) acrylate,

Isostearyl (meth) acrylate, phenyl (meth) acrylate,

Benzyl (meth) acrylate, dodecyl (meth) acrylate,

Tetrahydrofurfuryl (meth) acrylate, cyclohexyl (meth) acrylate,

4-n-butyl cyclohexyl (meth) acrylate,

2-ethylhexyl diglycol (meth) acrylate, butoxyethyl (meth) acrylate,

Butoxymethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate,

2- (2-methoxyethoxy) ethyl (meth) acrylate,

2- (2-butoxyethoxy) ethyl (meth) acrylate,

4-butylphenyl (meth) acrylate, phenyl (meth) acrylate,

2,4,5-tetramethylphenyl (meth) acrylate, phenoxymethyl (meth) acrylate,

Phenoxyethyl (meth) acrylate,

Polyethylene oxide monoalkyl ether (meth) acrylate,

Polyethylene oxide monoalkyl ether (meth) acrylate,

Polypropylene oxide monoalkyl ether (meth) acrylate,

Trifluoroethyl (meth) acrylate,

Pentadecafluorooxyethyl (meth) acrylate, 2-chloroethyl (meth) acrylate,

2, 3- dibromopropyl (meth) acrylate, tribromophenyl (meth) acrylate, etc. are mentioned. These components (a-1) may be used independently or may be used in combination of 2 or more type.

Among these components (a-1), methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate and tert-butyl acrylate are preferable, and methyl acrylate, ethyl acrylate and n-butyl acrylate are preferred. Is more preferable, and methyl acrylate and n-butyl acrylate are especially preferable.

The usage-amount of a component (a-1) is 99.5-80 mass parts, it is preferable that it is 99.2-88.0 mass parts, with the total amount of components (a-1)-(a-3) 100 mass parts, 99.0-93.0 mass It is more preferable to deny it.

(a-2) A hydroxyl group containing (meth) acrylic-type monomer (henceforth only called "component (a-2)") is an acryl-type monomer which has a hydroxyl group in a molecule | numerator. As a specific example of the component (a-2), for example,

2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate,

1,6-hexanediol mono (meth) acrylate,

Pentaerythritol tri (meth) acrylate,

Dipentaerythritol penta (meth) acrylate,

Neopentylglycol mono (meth) acrylate,

Trimethylolpropane di (meth) acrylate,

Trimethylolethane di (meth) acrylate,

2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate,

2-hydroxy-3-phenyloxypropyl (meth) acrylate,

4-hydroxycyclohexyl (meth) acrylate, 2-hydroxyethylacrylamide,

Cyclohexane dimethanol monoacrylate, etc. are mentioned, Glycidyl-group containing compounds, such as alkyl glycidyl ether, allyl glycidyl ether, and glycidyl (meth) acrylate, and (meth) The compound etc. which are obtained by addition reaction with acrylic acid are mentioned. These components (a-2) may be used independently or may be used in combination of 2 or more type.

Among these components (a-2), 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl acrylamide and cyclohexane dimethanol monoacrylate are preferable. , 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and 2-hydroxyethyl acrylamide are more preferable, and 2-hydroxyethyl acrylate and 2-hydroxyethyl acryl Amide is particularly preferred.

The usage-amount of a component (a-2) is 0.5-10 mass parts, as for the total amount of components (a-1)-(a-3) 100 mass parts, It is preferable that it is 0.6-7 mass parts, It is 0.7-5 mass It is more preferable to deny it. When it exists in the said range, the crosslinking point which the hydroxyl group derived from the component (a-2) in a polymer (A), and the isocyanate-type hardening | curing agent (B) reacts does not become excessive, and the adhesive composition of this invention is excellent in heat resistance And flexibility.

As needed, the other monomer copolymerizable with component (a-1) and component (a-2) (henceforth only a "component (a-3)" is used) is used. Component (a-3) is not particularly limited. As a specific example of the component (a-3), for example,

Acrylic monomers having an epoxy group such as glycidyl (meth) acrylate and methylglycidyl (meth) acrylate;

Amino groups such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, N-tert-butylaminoethyl (meth) acrylate, and methacryloxyethyltrimethylammonium chloride (meth) acrylate Having an acrylic monomer;

Acrylic monomers having an amide group such as (meth) acrylamide, n-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, and N, N-methylene bis (meth) acrylamide;

Carboxyl groups, such as (meth) acrylic acid, 2-methacryloyloxysuccinic acid, 2-methacryloyloxyethyl maleic acid, 2-methacryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, etc. Acrylic monomer having a;

Acrylic monomer which has phosphoric acid groups, such as 2-methacryloyl oxyethyl diphenyl phosphate (meth) acrylate, a trimethacryloyl oxyethyl phosphate (meth) acrylate, and a triacryloyloxy ethyl phosphate (meth) acrylate ;

Acrylic monomers having sulfonic acid groups such as sodium sulfopropyl (meth) acrylate, sodium 2-sulfoethyl (meth) acrylate and sodium 2-acrylamido-2-methylpropane sulfonate;

Acrylic monomer which has urethane groups, such as urethane (meth) acrylate;

acrylic vinyl monomers having a phenyl group such as p-tert-butylphenyl (meth) acrylate and o-biphenyl (meth) acrylate;

2-acetoacetoxyethyl (meth) acrylate, vinyltrimethoxysilane, vinyltriethoxysilane, vinyl tris (β-methoxyethyl) silane, vinyltriacetylsilane, methacryloyloxypropyltrimethoxysilane Vinyl monomers having silane groups such as these;

Styrene, chloro styrene, alpha -methyl styrene, vinyltoluene, vinyl chloride, vinyl acetate, vinyl propionate, acrylonitrile, vinylpyridine and the like. These components (a-3) may be used independently or may be used in combination of 2 or more type.

Among these components (a-3), (meth) acrylic acid, (meth) acrylamide, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 2-acetoacetoxyethyl (meth) acrylate (Meth) acrylic acid, acrylamide, dimethylaminoethyl (meth) acrylate, 2-acetoacetoxyethyl (meth) acrylate are more preferable, and acrylic acid is particularly preferable.

As for the usage-amount of a component (a-3), it is 0-10 mass parts, as for the total amount of components (a-1)-(a-3) 100 mass parts, it is preferable that it is 0.2-5 mass parts, and 0.3-2 mass It is more preferable to deny it.

The manufacturing method of a hydroxyl-containing (meth) acrylic-type polymer (A) is not specifically limited, The solution polymerization method using a polymerization initiator, the emulsion polymerization method, suspension polymerization method, reverse phase suspension polymerization method, thin film polymerization method, and spraying Conventionally well-known methods, such as a legal method, can be used. As a polymerization control method, adiabatic polymerization method, temperature controlled polymerization method, isothermal polymerization method, etc. are mentioned. Moreover, in addition to the method of starting superposition | polymerization with a polymerization initiator, the method of irradiating radiation, an electron beam, an ultraviolet-ray, etc., and initiating superposition | polymerization can also be employ | adopted. Among them, a solution polymerization method using a polymerization initiator is preferable because the molecular weight can be easily controlled and impurities can be reduced. For example, the polymerization initiator is preferably 0.01 to 0.50 parts by mass based on 100 parts by mass of the total amount of the components (a-1) to (a-3) using ethyl acetate, toluene, methyl ethyl ketone, or the like as a solvent. In addition, it is obtained by making it react for 3 to 10 hours at reaction temperature of 60-90 degreeC under nitrogen atmosphere, for example. As said polymerization initiator, For example, Azo compounds, such as azobisisobutyronitrile, 2,2'- azobis (2-methyl-butyronitrile), azobiscyano valeric acid; tert-butylperoxy pivalate, tert-butylperoxybenzoate, tert-butylperoxy-2-ethylhexanoate, di-tert-butylperoxide, cumene hydroperoxide, benzoyl peroxide, tert-butylhydride Organic peroxides such as loperoxide; Inorganic peroxides, such as hydrogen peroxide, ammonium persulfate, potassium persulfate, and sodium persulfate, are mentioned. These may be used independently or may use 2 or more types together.

It is preferable that the weight average molecular weights (Mw) of the hydroxy group containing (meth) acrylic-type polymer (A) obtained by copolymerizing the said component (a-1)-(a-3) are 700,000-2 million, and 900,000- It is more preferable that it is 1.6 million. If the weight average molecular weight is less than 700,000, heat resistance may be insufficient. On the other hand, when a weight average molecular weight exceeds 2 million, stickiness may be low and adhesiveness may fall. In addition, in this invention, the weight average molecular weight shall employ | adopt the polystyrene conversion value measured by the method as described in an Example.

In addition, the said component (A) may be used independently, or may be used in combination of 2 or more type of polymer.

(B) Isocyanate  Hardener

In addition to the said component (A), the adhesive composition of this invention contains an isocyanate-type hardening | curing agent (henceforth only a "component (B)"). An isocyanate-type hardening | curing agent reacts and couple | bonds with the hydroxyl group in the said hydroxyl group containing (meth) acrylic-type polymer (A), and a polycarbonate diol (C), and forms a crosslinked structure.

The isocyanate-based curing agent used in the present invention is not particularly limited. Specifically, for example, triallyl isocyanate, dimer acid diisocyanate, 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate Cyanate (2,6-TDI), 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2 , 4'-MDI), 1,4-phenylene diisocyanate, xylylene diisocyanate (XDI), tetramethylxylidene diisocyanate (TMXDI), toluidine diisocyanate ( Aromatic diisocyanates, such as TODI) and 1, 5- naphthalene diisocyanate (NDI); Aliphatic diisocyanates such as hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), lysine diisocyanate, norbornene diisocyanatomethyl (NBDI) Nates; Alicyclic diisocyanates such as transcyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), H6-XDI (hydrogenated XDI), H12-MDI (hydrogenated MDI) Nates; Carbodiimide-modified diisocyanates of the diisocyanates; Or these isocyanurate modified diisocyanates etc. may be used. Moreover, the adduct of the said isocyanate compound and polyol compounds, such as a trimethylol propane, the beret body and isocyanurate body of these isocyanate compounds can also be used suitably.

The said isocyanate-type hardening | curing agent may be synthesize | combined, or a commercial item may be used. As a commercial item of an isocyanate-type hardening | curing agent, For example, Coronate L, Coronate HL, Coronate 2030, Coronate 2031 (above, Nippon Polyurethane Co., Ltd. product); Takenate (registered trademark) D-102, Takenate (registered trademark) D-110N, Takenate (registered trademark) D-200, Takenate (registered trademark) D-202 (above, Mitsui Chemical Co., Ltd.) Duranate (trademark) 24A-100, Duranate (trademark) TPA-100, Duranate (trademark) TKA-100, Duranate (trademark) P301-75E, Duranate (trademark) E402-90T, Duranate (Trademark) E405-80T, a duranate (trademark) TSE-100, a duranate (trademark) D-101, a duranate (trademark) D-201 (above, Asahi Kasei Chemicals Corporation make), etc. are mentioned. .

Among these isocyanate-based curing agents, Coronate L, Coronate HL, Takenate® D110N, and Duranate® 24A-100 are preferred, and Coronate L and Takenate® D110N are more preferred. Preferred, and coronate L is particularly preferred. Moreover, these isocyanate-type hardening | curing agents may be used independently, or may be used in combination of 2 or more type.

In this invention, it is preferable that the compounding quantity of a component (B) is 0.05-5 mass parts with respect to 100 mass parts of components (A). If it is this range, the adhesive composition of this invention can have the outstanding heat resistance and flexibility. The said compounding quantity becomes like this. More preferably, it is 0.05-1.0 mass part, More preferably, it is 0.05-0.7 mass part.

(C) polycarbonate Dior

In addition to the said component (A) and a component (B), the adhesive composition of this invention contains a polycarbonate diol (henceforth only a "component (C)").

The polycarbonate diol used in the present invention is not particularly limited. Polycarbonate diol is synthesize | combined by making phosgene, diaryl carbonate, or ethylene carbonate react with a diol compound or a bisphenol compound. As an example of this diol compound, 1, 3- propane diol, 1, 4- butane diol, 1, 5- pentane diol, 1, 6- hexane diol, 3-methyl -1,5-pentane diol, 1,8-octane diol, 2-methyl-1,8-octane diol, 1,9-nonane diol, 1,10-decane diol, 1,4-cyclohexane dimethanol, 1,3-cyclohexane dimethanol, 1,4-cyclohexane diol, 1,3-cyclohexane diol, tricyclohexane dimethanol, pentacyclopenta Alkylene diols having 2 to 12 carbon atoms such as decane dimethanol, 1,4-butane diol, 1,6-hexane diol, and 1,12-dodecane diol; Polyethers such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polybutylene glycol, polyhexamethylene glycol, polyheptamethylene glycol, polydecamethylene glycol And diols. Moreover, as an example of a bisphenol compound, bisphenol A, bisphenol F, methylene bis (4-hydroxyphenyl), etc. are mentioned, for example. A mixture of two or more of the diol compounds, a mixture of two or more of the bisphenol compounds, or a mixture of a diol compound and a bisphenol compound may also be used.

The said polycarbonate diol may be synthesize | combined, or a commercial item may be used. As a commercial item of polycarbonate, PCDL T6002, PCDL T6001, PCDL T5652, PCDL T5651, PCDL T5650J, PCDL T4672, PCDL T4671, PCDL T4692, PCDL T4691 (above, Asahi Kasei Chemicals Co., Ltd. product), PLACCEL CD-205, PLACCEL 205PL, PLACCEL 205HL, PLACCEL 210, PLACCEL 210PL, PLACCEL 210HL, PLACCEL 220, PLACCEL 220PL or PLACCEL 220HL (above, manufactured by Daisel Kagaku Kogyo Co., Ltd.).

Among these polycarbonate diols, PCDL T5650J and PCDL T5651 are preferable, and PCDL T5650J is more preferable.

It is preferable that it is 500-1500, and, as for the number average molecular weight of the said polycarbonate diol, it is more preferable that it is 700-1200. When the said number average molecular weight is less than 500, heat resistance may fall. On the other hand, when it exceeds 1500, compatibility with a component (A) falls and there exists a possibility that an adhesive composition may whiten. In addition, in this invention, the number average molecular weight shall employ | adopt the value measured by the method as described in the Example mentioned later.

Moreover, the said polycarbonate diol may be used independently, or may be used in combination of 2 or more type.

In this invention, it is preferable that the compounding quantity of the said polycarbonate diol (C) is 0.1-5 mass parts with respect to 100 mass parts of components (A). If it is this range, the adhesive composition of this invention can have the outstanding heat resistance and flexibility. The said compounding quantity becomes like this. Preferably it is 0.2-4 mass parts, More preferably, it is 0.3-3 mass parts.

Moreover, the adhesive composition of this invention may contain a silane coupling agent in addition to the said components (A)-(C). By using a silane coupling agent, reactivity improves and the mechanical strength and adhesive strength of hardened | cured material can be improved. Such a silane coupling agent is not specifically limited. Specifically, for example

Methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane,

n-propyltrimethoxysilane, ethyltrimethoxysilane, diethyldiethoxysilane,

n-butyltrimethoxysilane, n-hexyltriethoxysilane, n-octyltrimethoxysilane,

Phenyltrimethoxysilane, diphenyldimethoxysilane,

Cyclohexylmethyldimethoxysilane, vinyltrichlorosilane,

Vinyl trimethoxysilane, vinyl triethoxysilane,

Vinyl tris (β-methoxyethoxy) silane,

β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane,

γ-glycidoxypropyltrimethoxysilane,

γ-glycidoxypropyltriethoxysilane,

γ-methacryloxypropylmethyldimethoxysilane,

γ-methacryloxypropyltrimethoxysilane,

γ-methacryloxypropylmethyldiethoxysilane

γ-methacryloxypropyltriethoxysilane,

γ-acryloxypropyltrimethoxysilane,

N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane,

N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane,

N-β- (aminoethyl) -γ-aminopropyltriethoxysilane,

γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,

N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane,

γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane,

Bis- (3- [triethoxysilyl] propyl) tetrasulfide,

(gamma)-isocyanate propyl triethoxysilane etc. are mentioned. Moreover, the silane coupling agent which has functional groups, such as an epoxy group (glycidoxy group), an amino group, a mercapto group, and a (meth) acryloyl group, the silane coupling agent containing the functional group reactive with these functional groups, another coupling agent, poly The compound which has a hydrolyzable silyl group obtained by making isocyanate etc. react with arbitrary functional groups at arbitrary ratios can also be used.

The said silane coupling agent may synthesize | combine, or may use a commercial item. As a commercial item of a silane coupling agent, it is KBM-303, KBM-403, KBE-402, KBM-403, KBE-502, KBE-503, KBM-5103, KEM-573, KBM-802, KBM-803, for example. , KBE-846, KBE-9007 (above, Shin-Etsu Chemical Co., Ltd. product), etc. are mentioned.

Among these silane coupling agents, KBM-303, KBM-403, KBE-402, KBM-403, KBM-5103, KBM-573, KBM-802, KBM-803, KBE-846, KBE-9007 are preferred, and KBM -403 is more preferable. In addition, the said silane coupling agent may be used independently, or may be used in combination of 2 or more type.

In the present invention, the amount of the silane coupling agent used is not particularly limited. Specifically, the blending amount of the silane coupling agent is preferably 0.01 to 5 parts by mass, more preferably 0.03 to 2.0 parts by mass, even more preferably based on 100 parts by mass of the total amount of the components (A) to (C). Preferably it is 0.05-0.5 mass part. If it is this range, the outstanding heat resistance and adhesiveness can be exhibited. When the compounding quantity of the said silane coupling agent is less than 0.01 mass part, glass adhesiveness may fall. On the other hand, when it exceeds 5.0 mass parts, heat resistance may fall.

In addition to the silane coupling agent or in place of the silane coupling agent, the pressure-sensitive adhesive composition of the present invention, an ionic liquid, an inorganic filler, a softener, an antioxidant, an antioxidant, a stabilizer, a tackifying resin, a modified resin (polyol resin, phenol) Resins, acrylic resins, polyester resins, polyolefin resins, epoxy resins, epoxidized polybutadiene resins, etc.), leveling agents, antifoaming agents, plasticizers, dyes, pigments (colored pigments, sieving pigments, etc.), treatment agents, sunscreen agents, fluorescence You may contain additives, such as brighteners, dispersants, thermal stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, lubricants and solvents. As the ionic liquid, for example, phosphonium ions, pyridinium ions, pyrrolidinium ions, imidazolium ions, guanidinium ions, ammonium ions, isurouronium ions, thiuronium ions, piperidinium Cationic components such as ions, pyrazolium ions, sulfonium ions, and anionic components include halogen ions, nitrate ions, sulfate ions, phosphate ions, perchlorate ions, thiocyanate ions, thiosulfate ions, sulfite ions, and tetrafluoro The substance which has an anion component, such as a bororate ion, a hexafluoro phosphate ion, a formate ion, an oxalic acid ion, an acetate ion, a trifluoroacetic acid ion, an alkylsulfonic acid ion, is mentioned. As antioxidant, dibutylhydroxytoluene (BHT), Irganox (trademark) 1010, Irganox (trademark) 1035FF, Irganox (trademark) 565 (all, Chiba specialty chemicals company) Products). As tackifying resin, rosin, such as rosin acid, polymerization rosin acid, and rosin acid ester, terpene resin, terpene phenol resin, aromatic hydrocarbon resin, aliphatic saturated hydrocarbon resin, petroleum resin, etc. are mentioned, for example. Although the usage-amount of an additive in the case of using the said additive is not restrict | limited, For example, it is 0.1-20 mass parts with respect to 100 mass parts of total amounts of the said components (A)-(C).

The pressure-sensitive adhesive composition of the present invention may be uniformly mixed by mixing each component described above in a batch, sequentially mixing the respective components, or mixing any of a plurality of components and then mixing the remaining components. It can manufacture by stirring. More specifically, it can prepare by heating at a temperature of 30-40 degreeC as needed, for example, and stirring for 10 minutes-5 hours, until it becomes uniform with a stirrer or the like.

The adhesive composition of this invention can be used for the joining of various base materials. As a base material which can be used here, glass, a plastic film, paper, a metal foil, etc. are mentioned. As glass, general inorganic glass is mentioned. Examples of the plastic in the plastic film include polyvinyl chloride resin, polyvinylidene chloride, cellulose resin, acrylic resin, cycloolefin resin, amorphous polyolefin resin, polyethylene, polypropylene, polystyrene, ABS resin, Polyamide, polyester, polycarbonate, polyurethane, polyvinyl alcohol, ethylene-vinyl acetate copolymer, and chlorinated polypropylene. The amorphous polyolefin resin usually has a polymerized unit of a cyclic polyolefin such as norbornene or a polycyclic norbornene monomer, and may be a copolymer of a cyclic olefin and a linear cyclic olefin. Examples of commercially available amorphous polyolefin resins include trade names ATON (ARTON) of JSR Corporation, ZEONEX (registered trademark) of Nihon Xeon Corporation, ZEONOR (registered trademark), APO of Mitsui Kagaku Co., Ltd., and Apel (registered trademark). . In order to form amorphous polyolefin resin into a film, well-known methods, such as a solvent casting method and a melt-extrusion method, are used suitably. Examples of the paper include imitation paper, fine paper, kraft paper, art coat paper, caster coated paper, pure white roll paper, parchment paper, water resistant paper, glassine paper, corrugated paper, and the like. As metal foil, aluminum foil etc. are mentioned, for example.

Therefore, this invention also provides the optical member provided with the adhesive layer formed from the adhesive composition of this invention.

As an optical member, a polarizing plate, a retardation plate, the optical film for plasma displays, the conductive film for touch panels, etc. are mentioned preferably, for example. Among these, the adhesive composition of this invention is excellent in the adhesiveness of a polarizing plate and glass. Of course, this invention is not limited to said form, It is also possible to use for adhesion | attachment of another member.

The adhesive composition of this invention may be used by directly apply | coating to one side or both surfaces of an optical film, and forming an adhesive layer, previously forming an adhesive layer on a peeling film, and transferring this to one side or both surfaces of an optical film. May be used.

Coating of the adhesive composition of this invention may be according to a conventionally well-known method, For example, a natural coater, a knife belt coater, a floating knife, a knife over roll, a knife on blanket, a spray, a dip, a kiss roll, a squeeze roll, reverse Various coating methods using apparatuses, such as a roll, an air blade, a curtain flow coater, a doctor blade, a wire bar, a die coater, a comma coater, a baker applicator, and a gravure coater, are mentioned. Moreover, what is necessary is just to select the coating thickness (thickness after drying) of the composition of this invention according to the base material to be used, and a use, Preferably it is 5-30 micrometers, More preferably, it is 15-25 micrometers.

The viscosity of the pressure-sensitive adhesive composition of the present invention is not particularly limited. However, in view of ease of coating, the viscosity at 25 ° C. is preferably 0.5 to 5.0 Pa · s, more preferably 1.0 to 3.0 Pa · s. If the said viscosity is less than 0.5 Pa.s, a bump may arise in a coating surface. On the other hand, when it exceeds 5.0 Pa.s, coating streaks may arise.

The pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition of the present invention is obtained by crosslinking the above pressure-sensitive adhesive composition. In that case, although crosslinking of an adhesive composition is generally performed after application | coating of an adhesive composition, it is also possible to transfer the adhesive layer which consists of an adhesive composition after crosslinking to a base material etc .. Crosslinking of this adhesive composition is normally performed by standing still on conditions of temperature 20-40 degreeC, relative humidity 30-70% RH, and normal pressure (atmospheric pressure).

The adhesive composition of this invention shows the outstanding flexibility, and thereby shows the outstanding rework property (repeelability) and workability. For example, in the bonding process of an optical member, even if the position shift of an optical film and a to-be-adhered body generate | occur | produces, an optical film can be peeled off without an adhesive remaining in a to-be-adhered body. When used for a polarizing plate especially, the outstanding light leakage resistance and rework property can be obtained.

In addition, since the adhesive composition of this invention has the outstanding heat resistance, it can express the high durability which does not produce lifting and peeling by heat processing or high humidity treatment.

[ Example ]

The effect of this invention is demonstrated using the following example and a comparative example. However, the technical scope of the present invention is not limited only to the following examples.

In addition, the measurement of the solid content and viscosity of the solution in which an adhesive composition melt | dissolves, and the weight average molecular weight of a hydroxyl group containing acrylic polymer (A), and the number average molecular weight of a polycarbonate diol (C) is performed with the following method. It was.

<Solid content>

Approximately 1 g of polymer solution is accurately weighed into an accurately weighed glass dish. After drying at 105 ° C for 1 hour, the temperature is returned to room temperature, and the total mass of the glass plate and the remaining solid content is accurately weighed. The solid content was computed by following formula (1) using X as the mass of a glass dish, the total mass of the glass dish before a drying, and a polymer solution as Y, and the total mass of a glass dish and remaining solid content as Z.

.

.

<Viscosity>

The adhesive solution put into the glass bottle was temperature-controlled at 25 degreeC, and it measured by the Brookfield viscometer.

<Weight average molecular weight and number average molecular weight>

It measured by the measuring method and measurement conditions of the following Table 1.

Equipment: Gel Permeation Chromatography GPC (Instrument No. GPC-16) Detector: Differential Refractive Index Detector RI (8020 Type Sensitivity 32, manufactured by Tosso Corporation) UV detector UV (Waters 2424, wavelength 215nm, sensitivity 0.2AUFS Column: Tosso Corporation TSKgel GMHXL (two), G2500HXL (one)
(S / N M0052, M0051, N0010, φ7.8 mm x 30 cm) Solvent: Tetrahydrofuran (manufactured by Wako Pure Chemical Industries, Ltd.) Flow rate: 1.0ml / min Column temperature: 23 ℃ Sample: [Concentration] about 0.2%
In the case of the hydroxyl group-containing acrylic polymer: 10 g of a measurement solvent was added to 0.1 g of the polymer solution.
In the case of polycarbonate diol: 10 g of a measuring solvent was added to 0.02 g of polycarbonate diol.
[Dissolution] The mixture was stirred gently at room temperature.
[Solubility] Soluble (visually confirmed)
Filtration It filtered on a 0.45 micrometer filter.
Injection volume: 0.200ml
Standard Sample: Monodisperse Polystyrene Data Processing: GPC Data Processing System

( Example  One)

99 parts by mass of n-butyl acrylate (manufactured by Nihon Shokubai Co., Ltd.), 1 part by mass of 2-hydroxyethyl acrylate (manufactured by Nihon Shokubai Co., Ltd.), acrylic acid (Nihon Shokubai Co., Ltd.) in a flask equipped with a reflux machine and a stirrer. Product) 1 part by mass and 130 parts by mass of ethyl acetate were added. Subsequently, it heated up to 65 degreeC, carrying out nitrogen substitution, 0.075 mass part of azobisisobutyronitrile (AIBN) was added, and superposition | polymerization was performed for 6 hours, maintaining 65 degreeC. After completion of the polymerization reaction, 270 parts by mass of ethyl acetate was added to dilute to obtain a solution of a hydroxyl group-containing acrylic polymer (A). Solid content of the obtained polymer solution was 19.0 mass%, and the viscosity was 4.0 Pa * s. Moreover, the weight average molecular weight of the obtained hydroxyl group containing acrylic polymer (A) was 1.2 million.

Next, the polymer solution obtained above, coronate L (trimethylolpropane / tolylene diisocyanate trimer adduct which is an isocyanate type hardening | curing agent (B), product made by Nippon Polyurethane Co., Ltd. product). ) PCDL T5650J (diol component: 1,6-hexane diol and 1,5-pentane diol, product of Asahi Kasei Chemicals Co., Ltd.) which is 0.2 mass part, polycarbonate diol (C), number average molecular weight : 800) 0.5 parts by mass and 0.1 parts by mass of KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a silane coupling agent were mixed at 25 ° C. for 15 minutes to obtain a solution in which the pressure-sensitive adhesive composition was dissolved.

This solution was apply | coated using the baker applicator on the peeling PET film (Mitsubishi Chemical Co., Ltd. product, MRF38, thickness: 38 micrometers) so that the thickness after drying might be 25 micrometers, and it stuck to the polarizing plate. Then, it aged for 7 days under 23 degreeC / 45% RH conditions, and obtained the sample for evaluation.

( Example  2-7, Comparative example  1 to 3)

Samples for preparation and evaluation of the solution in which the pressure-sensitive adhesive composition is dissolved in the same manner as in Example 1, except that monomers, isocyanates, polycarbonate diols, and silane coupling agents were used in the composition ratios shown in Table 2 below. Was produced.

About the evaluation samples of Examples 1-7 and Comparative Examples 1-3 obtained as mentioned above, heat resistance, moisture heat resistance, light leakage resistance, adhesive force, and rework property were evaluated in accordance with the following method.

<Heat resistance test>

The sample cut | judged to the magnitude | size of 120 mm (polarizing plate MD direction) x 60 mm was stuck to the glass plate, and autoclave process was performed for 20 minutes on 50 degreeC and 0.49 Mpa (5 kg / cm <2>) conditions. Then, it put in 80 degreeC environment and observed the appearance after 120 hours. In addition, in the following Table 2, "good" means that peeling of a glass plate and a polarizing plate did not generate | occur | produce, and that peeling with a glass plate and a polarizing plate with "peeling" produced the bubble in an adhesive layer with "foaming". It means that each has occurred.

Moisture and Heat Resistance Test

The sample cut | judged to the magnitude | size of 120 mm (polarizing plate MD direction) x 60 mm was stuck to the glass plate, and autoclave process was performed for 20 minutes on 50 degreeC and 0.49 Mpa (5 kg / cm <2>) conditions. Then, it put in 60 degreeC / 90% RH environment, and observed the appearance after 120 hours. In addition, in the following Table 2, "good | favorableness" means that peeling of the glass plate and the polarizing plate did not generate | occur | produced, and that external appearance was favorable, and that "peeling" means that peeling of the glass plate and the polarizing plate respectively occurred.

<Light leakage test>

A sample cut to a size of 120 mm (polarizing plate MD direction) x 60 mm and a sample cut to a size of 120 mm (polarizing plate TD direction) x 60 mm are pasted so as to overlap each surface of the glass plate, and 50 ° C and 0.49 MPa. The autoclave process was performed for 20 minutes on condition of (5 kg / cm <2>). Then, it put in 80 degreeC environment and observed the appearance after 120 hours. In addition, in Table 2 below, "good" means that light leakage hardly occurred, and "defect" means that the edge part of the polarizing plate was whitened, and since "unevaluation" with peeling between a glass plate and a polarizing plate was evaluated, The "dotted omission" means that the phenomenon (a state such as a dot omission) which light leaked to the point shape by the foaming by the foaming, respectively, was not able to mean.

<Adhesion and Reworkability>

The sample cut | disconnected to 25 mm width was stuck to the glass plate, and the autoclave process was performed for 20 minutes on 50 degreeC and 0.49 Mpa (5 kg / cm <2>) conditions. Then, using the tensile tester, the adhesive force was measured and the peeling state was observed at the peel angle of 90 degrees, and the peel rate 0.3m / min (measurement environment: 20 degreeC / 50% RH). In addition, in Table 2 below, "af" means interfacial failure, and "electrodeposition" means peeling between the pressure-sensitive adhesive and the polarizing plate, and indicates that the pressure-sensitive adhesive layer remained on the glass plate, respectively.

The evaluation results of each test are shown in Table 2 below.

As can be seen from Table 2, the optical members (Examples 1 to 7) using the pressure-sensitive adhesive composition of the present invention has Comparative Examples 1-2 and hydroxy groups in which the content of polycarbonate diol is outside the range of the present invention. Compared with the optical member using the adhesive composition of the comparative example 3 which does not use the acryl-type polymer, it turns out that it is excellent in heat resistance, moist heat resistance, light leakage resistance, and rework resistance.

1 is a schematic diagram showing a crosslinked structure of a conventional pressure-sensitive adhesive composition;

2 is a schematic diagram showing a crosslinked structure of the pressure-sensitive adhesive composition of the present invention.

<Code description>

1: acrylic resin

2, B: isocyanate curing agent

3: polyol

A: (meth) acrylic-type polymer containing a hydroxyl group

C: polycarbonate diol.

Claims (4)

(a-1) 99.5-80 mass parts of (meth) acrylate-type monomers, 0.5-10 mass parts of (a-2) hydroxyl-containing (meth) acrylic-type monomers, and (a-3) said (a-1) and A hydroxyl group-containing (meth) acrylic system formed by polymerizing 0 to 10 parts by mass of other monomers copolymerizable with (a-2) (wherein the total amount of (a-1) to (a-3) is 100 parts by mass). Polymer (A); Isocyanate-based curing agent (B); And Adhesive composition containing a polycarbonate diol (C). The method of claim 1, A pressure-sensitive adhesive composition further comprising a silane coupling agent. The method of claim 1, The compounding quantity of the said isocyanate-type hardening | curing agent (B) is 0.05-5 mass parts with respect to 100 mass parts of said hydroxyl-group containing (meth) acrylic-type polymers (A), The compounding quantity of the said polycarbonate diol (C) is 0.1-5 mass parts with respect to 100 mass parts of said hydroxyl-group containing (meth) acrylic-type polymers (A). The optical member provided with the adhesive layer formed from the adhesive composition in any one of Claims 1-3.

Images