KR102066921B1 - Adhesive Composition and Polarizing Plate Comprising the Same - Google Patents

Abstract

The present invention provides an ionic functional group-containing acrylic copolymer prepared by the reaction of an acrylic copolymer containing an epoxy group and an ionic compound containing a carboxylic acid group, a pressure-sensitive adhesive composition, a polarizing plate, and a liquid crystal display device. The pressure-sensitive adhesive composition according to the present invention is high in adhesive strength and excellent in durability.

Description

Adhesive composition and polarizing plate including same {Adhesive Composition and Polarizing Plate Comprising the Same}

The present invention relates to an adhesive composition and a polarizing plate including the same, and more particularly, to an adhesive composition having high adhesive strength and excellent durability, a polarizing plate and a liquid crystal display device including the same.

A liquid crystal display device (LCD) includes a liquid crystal panel including a liquid crystal cell and a polarizing plate bonded to both surfaces of the liquid crystal cell via an adhesive layer.

The pressure-sensitive adhesive for bonding the liquid crystal cell and the polarizing plate is light leakage caused by the durability of heat resistance, moisture heat resistance, thermal shock resistance, cold resistance, etc., reworking in case of bonding error or mixing of foreign materials, and shrinkage stress of the polarizing plate under heat resistance conditions. In order to prevent the antistatic property, the antistatic property for the prevention of static electricity generated when the release film is removed for the polarizing plate bonding must be satisfied at the same time. Among these, since the characteristics of the pressure-sensitive adhesive required for satisfying durability and reworkability are in conflict with each other, satisfying all of them has not been completely solved.

Japanese Laid-Open Patent Publication No. 2008-285670 discloses an adhesive composition containing an acrylic resin obtained by copolymerizing an (meth) acrylic acid alkyl ester with an ionic liquid containing a polymerizable unsaturated group. It is described as having excellent performance. However, the ionic liquid containing a polymerizable unsaturated group is insufficient in solubility in an organic solvent, making it difficult to copolymerize various ionic compounds, and the copolymer is uniformly produced when using an ionic monomer having insufficient solubility. There is a problem that the coating is non-uniform because it is not manufactured.

Japanese Patent Laid-Open No. 2008-285670

The present invention is to solve the above problems, an object of the present invention is to provide an ionic functional group-containing acrylic copolymer in which various ionic functional groups are introduced into the acrylic copolymer.

Another object of the present invention is to provide a method for uniformly preparing an acrylic copolymer containing various ionic functional groups.

Still another object of the present invention is to provide a pressure-sensitive adhesive composition having high adhesive strength and excellent durability, including the ionic functional group-containing acrylic copolymer.

Still another object of the present invention is to provide a polarizing plate in which a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition is laminated.

Still another object of the present invention is to provide a liquid crystal display device having the polarizing plate on at least one side of a liquid crystal cell.

On the other hand, this invention provides the ionic functional group containing acrylic copolymer manufactured by reaction of the acrylic copolymer containing an epoxy group and the ionic compound containing a carboxylic acid group.

In one embodiment of the present invention, the acrylic copolymer containing an epoxy group can be produced by copolymerization of a (meth) acrylate monomer with a monomer containing an unsaturated double bond and an epoxy group in the molecule at the same time.

In one embodiment of the present invention, the ionic compound containing a carboxylic acid group may be at least one selected from compounds of the formulas (I) to (III).

[Formula I]

[Formula II]

[Formula III]

In the above formula,

X is nitrogen, phosphorus or sulfur,

R ₁ and R ₂ are each independently a C ₁ -C ₁₀ alkyl group or an aryl group,

R ₃ is a C ₁ -C ₁₀ alkyl or aryl group when X is nitrogen or phosphorus, and is absent when X is sulfur,

R ₄ is an alkyl group of C ₁ -C ₁₀ ,

Y is a C ₁ -C ₆ alkylene or arylene group,

n is an integer from 1 to 5,

L is an anion.

On the other hand, the present invention provides a method for producing an ionic functional group-containing acrylic copolymer comprising the step of reacting an acrylic copolymer containing an epoxy group and an ionic compound containing a carboxylic acid group.

On the other hand, the present invention provides a pressure-sensitive adhesive composition comprising the ionic functional group-containing acrylic copolymer, crosslinking agent and silane coupling agent.

On the other hand, the present invention provides a polarizing plate in which the pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition is laminated.

On the other hand, the present invention provides a liquid crystal display device having the polarizing plate on at least one side of the liquid crystal cell.

The pressure-sensitive adhesive composition comprising an ionic functional group-containing acrylic copolymer according to the present invention can be introduced into a variety of ionic functional groups in the acrylic copolymer, the copolymer is uniformly produced, the coating can be formed uniformly, the adhesive force is high Excellent durability

Hereinafter, the present invention will be described in more detail.

One embodiment of the present invention relates to an ionic functional group-containing acrylic copolymer prepared by the reaction of an acrylic copolymer containing an epoxy group and an ionic compound containing a carboxylic acid group.

In one embodiment of the present invention, the acrylic copolymer containing an epoxy group can be produced by copolymerization of a (meth) acrylate monomer with a monomer containing an unsaturated double bond and an epoxy group in the molecule at the same time.

In one embodiment of the present invention, the monomer containing the unsaturated double bond and the epoxy group in the molecule at the same time may be a (meth) acrylate containing an epoxy group. Specific examples may be one or more selected from compounds of Formulas 1 to 4 below.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

It is preferable that the monomer which contains the said unsaturated double bond and an epoxy group simultaneously in a molecule | numerator is contained in 1 to 20 weight% with respect to 100 weight% of the acryl-type copolymer containing the said epoxy group, and it is more preferable that it is 2 to 10 weight%. If the content is less than 1% by weight, the content of the generated ionic functional groups is insufficient, and thus the adhesion improvement effect is insufficient. Therefore, if the content is more than 20% by weight, the polarity of the polymer is increased to facilitate the absorption of moisture. There exists a possibility that peeling may generate | occur | produce in damp-heat conditions.

In one embodiment of the present invention, the (meth) acrylate monomer may be a (meth) acrylate monomer having an alkyl group having 1 to 12 carbon atoms. Specific examples include n-butyl (meth) acrylate, 2-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, Ethyl (meth) acrylate, methyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, pentyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl ( Meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, and the like. Can be used. Among these, n-butyl acrylate, 2-ethylhexyl acrylate, or a mixture thereof is preferable.

The (meth) acrylate monomer is preferably contained in 80 to 99% by weight, more preferably 90 to 95% by weight relative to 100% by weight of the total monomers used in the production of the acrylic copolymer. If the content is less than 80% by weight, the adhesive force is not sufficient, and when the content is more than 99% by weight, cohesion may be lowered.

In one embodiment of the present invention, the acrylic copolymer containing an epoxy group is a copolymer of a (meth) acrylate monomer, a monomer containing an unsaturated double bond and an epoxy group in a molecule at the same time, and a monomer having a functional group crosslinkable with these. Can be.

The monomer which has a crosslinkable functional group can use the monomer which has a hydroxyl group as a component which provides cohesion force or adhesive strength by chemical bond with the following crosslinking agent.

As a monomer which has a hydroxyl group, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 2-hydroxyethylene glycol (meth) acrylate, 2-hydroxypropylene glycol (meth) acrylate, hydroxyalkylene glycol having 2 to 4 carbon atoms of an alkylene group ( Methacrylate, etc. are mentioned, Among these, 2-hydroxyethyl (meth) acrylate is preferable.

It is preferable that the monomer which has a crosslinkable functional group is contained in 1 to 20 weight% with respect to 100 weight% of total monomers used for manufacture of an acryl-type copolymer, and it is more preferable that it is 1 to 10 weight%. When the content is less than 1% by weight, cohesion may be lowered, and when the content is greater than 20% by weight, the gel fraction may be excessively increased to decrease the adhesive force.

In addition, other polymerizable monomers in addition to the monomers may be further included in a range that does not lower the adhesion, such as 10% by weight or less, preferably 5% by weight or less.

The production method of the copolymer is not particularly limited, and may be prepared using a method such as bulk polymerization, solution polymerization, emulsion polymerization or suspension polymerization, which are commonly used in the art, and solution polymerization is preferable. In addition, a solvent, a polymerization initiator, a chain transfer agent for molecular weight control, and the like, which are usually used in the polymerization, may be used.

The acrylic copolymer has a weight average molecular weight (polystyrene equivalent) measured by gel permeation chromatography (GPC) in general of 50,000 to 2,000,000, preferably 1,000,000 to 2,000,000.

In one embodiment of the present invention, the ionic compound containing a carboxylic acid group may be at least one selected from compounds of the formulas (I) to (III).

[Formula I]

[Formula II]

[Formula III]

In the above formula,

X is nitrogen, phosphorus or sulfur,

R ₁ and R ₂ are each independently a C ₁ -C ₁₀ alkyl group or an aryl group,

R ₃ is a C ₁ -C ₁₀ alkyl or aryl group when X is nitrogen or phosphorus, and is absent when X is sulfur,

R ₄ is an alkyl group of C ₁ -C ₁₀ ,

Y is a C ₁ -C ₆ alkylene or arylene group,

n is an integer from 1 to 5,

L is an anion.

As used herein, an alkyl group of C ₁ -C ₁₀ refers to a straight or branched monovalent hydrocarbon having 1 to 10 carbon atoms, for example methyl, ethyl, n-propyl, i-propyl, n-butyl , i-butyl, t-butyl, n-pentyl, n-hexyl, n-octyl, n-decyl and the like.

As used herein, the aryl group includes both aromatic groups and heteroaromatic groups and their partially reduced derivatives. The aromatic group is a simple or fused cyclic consisting of 5 to 15 pentagons, heteroaromatic group refers to an aromatic group containing one or more oxygen, sulfur or nitrogen. Examples of representative aryl groups include phenyl, naphthyl, pyridinyl, furanyl, thiophenyl, indolyl, quinolinyl, imidazolinyl, Oxazolyl, thiazolyl, tetrahydronaphthyl, and the like, but are not limited thereto.

As used herein, an alkylene group of C ₁ -C ₆ refers to a straight or branched divalent hydrocarbon having 1 to 6 carbon atoms, and includes, for example, methylene, ethylene, propylene, butylene, and the like. It doesn't happen.

The C ₁ -C ₁₀ alkyl group, aryl group and C ₁ -C ₆ alkylene group is one or more hydrogen is C ₁ -C ₆ alkyl group, C ₂ -C ₆ alkenyl group, C ₂ -C ₆ Alkynyl group, C ₃ -C ₁₀ cycloalkyl group, C ₃ -C ₁₀ heterocycloalkyl group, C ₃ -C ₁₀ heterocycloalkyloxy group, C ₁ -C ₆ haloalkyl group, C ₁ -C ₆ It may be substituted with an alkoxy group, a C ₁ -C ₆ thioalkoxy group, an aryl group, an acyl group, hydroxy, thio, halogen, amino, alkoxycarbonyl, carboxy, carbamoyl, cyano, nitro and the like. .

In one embodiment of the invention,

X is nitrogen, phosphorus or sulfur,

R ₁ and R ₂ are each independently C ₁ -C ₁₀ alkyl or phenyl group,

R ₃ is a C ₁ -C ₁₀ alkyl or phenyl group when X is nitrogen or phosphorus, and is absent when X is sulfur,

R ₄ is an alkyl group of C ₁ -C ₁₀ ,

Y is C ₁ -C ₆ alkoxy group and a phenyl group substituted by one or more substituents selected from the group or unsubstituted C ₁ -C ₆ alkylene group or a phenylene group consisting of,

n is an integer from 1 to 5,

L is halide, hexafluorophosphate, p-toluenesulfonate, methanesulfonate, trifluoromethanesulfonate or bis (trifluoromethylsulfonyl) imide.

In one embodiment of the present invention, a representative compound of the ionic compound containing a carboxylic acid group may be selected from compounds of the formula 5 to 17.

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

One embodiment of the present invention relates to a method for producing an ionic functional group-containing acrylic copolymer comprising the step of reacting an acrylic copolymer containing an epoxy group and an ionic compound containing a carboxylic acid group.

In one embodiment of the present invention, when an acrylic copolymer containing an epoxy group and an ionic compound containing a carboxylic acid group are reacted, an ionic functional group-containing acrylic copolymer is prepared, for example, as shown in Scheme 1 below.

 Scheme 1

The reaction can be carried out easily according to methods known in the art, preferably in the presence of a trialkylamine or tetraalkylammonium catalyst.

Triethylamine, tributylamine, etc. may be used as the trialkylamine catalyst, and tetrabutylammonium bromide, tetrabutylammonium iodide, etc. may be used as the tetraalkylammonium catalyst.

One embodiment of the present invention relates to an adhesive composition comprising the ionic functional group-containing acrylic copolymer, a crosslinking agent, and a silane coupling agent.

In one embodiment of this invention, the said crosslinking agent is a component for strengthening the cohesion force of an adhesive by crosslinking a copolymer suitably, The kind is not specifically limited. For example, an isocyanate type compound, an epoxy type compound, etc. are mentioned, These can be used individually or in mixture of 2 or more types.

As the isocyanate compound, tolylene diisocyanate, xylene diisocyanate, 2,4-diphenylmethane diisocyanate, 4,4-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, tetramethyl xylene diisocyanate, naphthalene Diisocyanate compounds such as diisocyanate; Diisocyanate obtained from 2 moles of an adduct obtained by reacting 3 moles of a diisocyanate compound with 1 mole of a polyhydric alcohol compound such as trimethylolpropane, an isocyanurate obtained by self-condensing 3 moles of the diisocyanate compound, and 3 moles of the diisocyanate compound And polyfunctional isocyanate compounds containing three functional groups such as biuret, triphenylmethanetriisocyanate, and methylenebistriisocyanate, in which the remaining 1 mole of diisocyanate is condensed to urea.

Examples of the epoxy compounds include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol. Diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, polytetramethylene glycol diglycidyl ether, glycerol diglycidyl ether, glycerol triglycidyl ether, Diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, resorcin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, trimethylol propane triglycidyl ether, pentaerythritol Polyglycidyl ether, sorbitol polyglycidyl ether, adipic acid diglycidyl ester, phthalic acid diglycidyl ester, tris (glycidyl) isocyanur Tris (glycidoxyethyl) isocyanurate, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-m- Xylylenediamine etc. are mentioned.

Moreover, melamine type compound can be used individually or in mixture of 2 or more types together with an isocyanate type compound and an epoxy type compound.

Hexamethylol melamine, hexamethoxymethylmelamine, hexabutoxymethylmelamine, etc. are mentioned as a melamine type compound.

The crosslinking agent may be included in an amount of 0.1 to 15 parts by weight, and more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the acrylic copolymer based on the solid content. If the content is less than 0.1 part by weight, the cohesion force becomes small due to insufficient crosslinking degree, which may cause durability deterioration such as lifting and damage of cutting property. If the content is more than 15 parts by weight, problem of relaxation of residual stress may occur due to excessive crosslinking reaction. have.

In one embodiment of the present invention, the type of the silane coupling agent is not particularly limited, and for example, vinylchlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltri Methoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-sty Aryltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (Aminoethyl) -3-aminopropylmethyltriethoxysilane, 3-aminopropyltrimethoxysil , 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-chloropropyltri Methoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxysilane, etc. are mentioned. have. These can be used individually or in mixture of 2 or more types.

The silane coupling agent is preferably included in an amount of 0.01 to 5 parts by weight, and more preferably 0.05 to 2.5 parts by weight based on 100 parts by weight of the acrylic copolymer based on the solid content. If the content is less than 0.01 parts by weight, the adhesion with the substrate to be bonded under a damp-heat environment may be lowered. If the content is more than 5 parts by weight, bubbles or peeling may occur, which may lower durability.

The pressure-sensitive adhesive composition according to an embodiment of the present invention, in addition to the components described above, in order to adjust the adhesion, cohesion, viscosity, elastic modulus, glass transition temperature, antistatic properties, etc. required according to the use, tackifying resin, antioxidant, It may further include additives such as corrosion inhibitors, leveling agents, surface lubricants, dyes, pigments, antifoaming agents, fillers, light stabilizers, antistatic agents.

The adhesive composition of this invention can be used also as an adhesive for surface protection films as well as the adhesive for polarizing plates for bonding with a liquid crystal cell. In addition, it can be used as a protective film, a reflective sheet, a structural adhesive sheet, a photo adhesive sheet, a lane display adhesive sheet, an optical adhesive product, an adhesive for an electronic component, as well as a general commercial adhesive sheet product and a medical patch.

One embodiment of the present invention relates to a polarizing plate in which a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition is laminated.

The thickness of the pressure-sensitive adhesive layer can be adjusted according to the adhesive force, it is usually preferably from 3 to 100㎛, more preferably from 10 to 100㎛.

Such a polarizing plate can be applied to all conventional liquid crystal display devices, and in particular, a liquid crystal display device including a liquid crystal panel in which the polarizing plate on which the pressure-sensitive adhesive layer is laminated is bonded to at least one surface of a liquid crystal cell can be configured.

Accordingly, one embodiment of the present invention relates to a liquid crystal display device having the polarizing plate on at least one side of a liquid crystal cell.

Hereinafter, the present invention will be described in more detail with reference to Examples, Comparative Examples and Experimental Examples. These examples, comparative examples and experimental examples are only for illustrating the present invention, it is apparent to those skilled in the art that the scope of the present invention is not limited thereto.

Preparation Example 1 Preparation of Ionic Functional Containing Acrylic Copolymer

90 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), and 8 parts by weight of the compound of formula (1) in a 1 L reactor equipped with a refrigeration system to facilitate nitrogen temperature reflux and temperature control. After the monomer mixture was added, ethyl acetate was used as a solvent. 100 parts by weight was added. Then, after purging nitrogen gas for 1 hour to remove oxygen, it was maintained at 62 ℃. After homogenizing the mixture, 0.07 parts by weight of azobisisobutyronitrile (AIBN) was added as a reaction initiator, and reacted for 6 hours to synthesize an acrylic copolymer having an epoxy group having a weight average molecular weight of about 1 million.

Then, a solution in which 7 parts by weight of the compound of Formula 5 was dissolved in 100 parts by weight of acetonitrile was added, and further reacted at the same temperature for 24 hours to prepare an ionic functional group-containing acrylic copolymer.

After taking a portion of the reaction mixture and blowing the nitrogen to remove the solvent, NMR was measured to confirm that no compound of formula 5 remained, it was confirmed that the compound of formula 5 reacted with the acrylic copolymer.

Preparation Example 2 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 2 was used instead of the compound of Formula 1.

Preparation Example 3 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 3 was used instead of the compound of Formula 1.

Preparation Example 4 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 8 was used instead of the compound of Formula 5.

Preparation Example 5 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 9 was used instead of the compound of Formula 5.

Preparation Example 6 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 11 was used instead of the compound of Formula 5.

Preparation Example 7 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 12 was used instead of the compound of Formula 5.

Preparation Example 8 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 13 was used instead of the compound of Formula 5.

Preparation Example 9 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 14 was used instead of the compound of Formula 5.

Preparation Example 10 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 15 was used instead of the compound of Formula 5.

Preparation Example 11 Preparation of Ionic Functional Containing Acrylic Copolymer

90 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), 94 parts by weight of n-butyl acrylate (BA) instead of 8 parts by weight of the compound of formula 1, hydroxyethyl acrylate (HEA) 2 parts by weight, 4 parts by weight of the compound of Formula 1, and 3 parts by weight instead of 7 parts by weight of the compound of Formula 5, proceeding in the same manner as in Preparation Example 1 and the ionic functional group-containing acrylic copolymer Was prepared.

Preparation Example 12 Preparation of Ionic Functional Containing Acrylic Copolymer

90 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), 97 parts by weight of n-butyl acrylate (BA) instead of 8 parts by weight of the compound of formula (2), hydroxyethyl acrylate (HEA) 2 parts by weight, 1 part by weight of the compound of formula (1), 1 part by weight instead of 7 parts by weight of the compound of formula (5) was carried out in the same manner as in Preparation Example 1 and the ionic functional group-containing acrylic copolymer Was prepared.

Preparation Example 13 Preparation of Ionic Functional Containing Acrylic Copolymer

90 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), 83 parts by weight of n-butyl acrylate (BA) instead of 8 parts by weight of the compound of formula (2), hydroxyethyl acrylate (HEA) 2 parts by weight, 15 parts by weight of the compound of Formula 1, and 10 parts by weight instead of 7 parts by weight of the compound of Formula 5, proceeding in the same manner as in Preparation Example 1 and the ionic functional group-containing acrylic copolymer Was prepared.

Preparation Example 14 Preparation of Ionic Functional Containing Acrylic Copolymer

90 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), 73 parts by weight of n-butyl acrylate (BA) instead of 8 parts by weight of the compound of formula (2), hydroxyethyl acrylate (HEA) 2 parts by weight, 25 parts by weight of the compound of Formula 1, and 20 parts by weight instead of 7 parts by weight of the compound of Formula 5, proceeding in the same manner as in Preparation Example 1 and the ionic functional group-containing acrylic copolymer Was prepared.

Preparation Example 15 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 16 was used instead of the compound of Formula 5.

Preparation Example 16 Preparation of Ionic Functional Containing Acrylic Copolymer

An ionic functional group-containing acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the compound of Formula 17 was used instead of the compound of Formula 5.

Comparative Production Example 1 Preparation of Acrylic Copolymer

Proceed as in Preparation Example 1, the addition reaction of the compound of Formula 5 did not proceed.

Comparative Preparation Example 2 Preparation of Copolymer Using Ionic Monomer

8중량부를 이용하여, 상기 제조예 1과 동일하게 진행하되, 이온화 반응은 추가적으로 진행하지 않았다.
90 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), 90 parts by weight of n-butyl acrylate (BA) instead of 8 parts by weight of the compound of formula 1, hydroxyethyl acrylate (HEA) 2 parts by weight,

Using 8 parts by weight, but proceeding in the same manner as in Preparation Example 1, the ionization reaction did not proceed further.

Comparative Production Example 3 Preparation of Acrylic Copolymer

Using 98 parts by weight of n-butyl acrylate (BA), 2 parts by weight of hydroxyethyl acrylate (HEA), it proceeded in the same manner as in Preparation Example 1, but the ionization reaction did not proceed further.

Examples 1 to 16 and Comparative Examples 1 to 3: Preparation of pressure-sensitive adhesive polarizing plate

Each component was mixed in the composition shown in Table 1 below (unit: parts by weight), and diluted with ethyl acetate to prepare a pressure-sensitive adhesive composition having a solid content concentration of 15%.

The pressure-sensitive adhesive composition prepared above was applied on a release film coated with a silicone release agent to have a thickness of 25 μm, and dried at 100 ° C. for 1 minute to form a pressure-sensitive adhesive layer.

A pressure-sensitive adhesive polarizing plate was prepared by laminating the pressure-sensitive adhesive layer prepared above on an iodine-based polarizing plate having a thickness of 185 μm by adhesive processing.

Copolymer Crosslinking agent Silane coupling agent Example 1 Preparation Example 1: 100 0.5 0.5 Example 2 Preparation Example 2: 100 0.5 0.5 Example 3 Preparation Example 3: 100 0.5 0.5 Example 4 Preparation Example 4: 100 0.5 0.5 Example 5 Preparation Example 5: 100 0.5 0.5 Example 6 Preparation Example 6: 100 0.5 0.5 Example 7 Preparation Example 7: 100 0.5 0.5 Example 8 Preparation Example 8: 100 0.5 0.5 Example 9 Preparation Example 9: 100 0.5 0.5 Example 10 Preparation Example 10 100 0.5 0.5 Example 11 Preparation Example 11: 100 0.5 0.5 Example 12 Preparation 12: 100 0.5 0.5 Example 13 Preparation Example 13: 100 0.5 0.5 Example 14 Preparation 14: 100 0.5 0.5 Example 15 Preparation 15: 100 0.5 0.5 Example 16 Preparation Example 16: 100 0.5 0.5 Comparative Example 1 Comparative Preparation Example 1: 100 0.5 0.5 Comparative Example 2 Comparative Preparation Example 2: 100 0.5 0.5 Comparative Example 3 Comparative Preparation Example 3: 100 0.5 0.5

Crosslinking agent: Coronate-L (Japan Urethane Co., Ltd.)

Silane coupling agent: KBM-403 (Shin-Etsu Corporation)

Experimental Example 1 Evaluation of Copolymer Preparation Properties and Durability

The physical properties of the pressure-sensitive adhesive polarizing plate prepared in Examples and Comparative Examples were measured by the following method, and the results are shown in Table 2 below.

(1) copolymer production characteristics

The homogeneity and gelling properties of the prepared copolymer were confirmed.

<Evaluation Criteria>

Unevenness of the copolymer solution is visually identified: ×

Non-uniformity in the copolymer solution was not observed visually:

(2) Heat resistance / humidity heat resistance evaluation

After removing the release film of the polarizing plate with a pressure-sensitive adhesive, and bonded the surface of the pressure-sensitive adhesive layer to Corning glass, after standing for 300 hours at 80 ℃ and 60 ℃ / 90 RH% conditions, respectively, the appearance was confirmed.

<Evaluation Criteria>

Bubble and Peeling 3 or more admitted: ×

Less than 2 bubbles and peelings are admitted: ○

Bubbles and Peelings Unidentified: ◎

division Copolymer Preparation Properties Heat resistance Moisture and Heat Resistance Example 1 ○ ◎ ◎ Example 2 ○ ◎ ◎ Example 3 ○ ◎ ◎ Example 4 ○ ◎ ◎ Example 5 ○ ◎ ◎ Example 6 ○ ◎ ◎ Example 7 ○ ◎ ◎ Example 8 ○ ◎ ◎ Example 9 ○ ◎ ◎ Example 10 ○ ◎ ◎ Example 11 ○ ◎ ◎ Example 12 ○ ○ ◎ Example 13 ○ ◎ ○ Example 14 ○ ○ ○ Example 15 ○ ◎ ◎ Example 16 ○ ◎ ◎ Comparative Example 1 ○ × × Comparative Example 2 × × × Comparative Example 3 ○ × ×

As shown in Table 1, the polarizing plates of Examples 1 to 16 including the ionic functional group-containing acrylic copolymer according to the present invention are compared to the polarizing plates of Comparative Examples 1 and 3 including the acrylic copolymer in which the addition reaction was not performed. The heat resistance and the heat and humidity resistance were remarkably excellent.

On the other hand, in the case of Comparative Example 2 including an ionic functional group-containing acrylic copolymer prepared by polymerizing an ionic monomer, heat resistance and heat and humidity resistance were low. This is interpreted because the copolymer is not uniformly prepared, so that the coating is nonuniform and bubbles and peeling are likely to be generated.

Having described the specific part of the present invention in detail, it is apparent to those skilled in the art that this specific technology is only a preferred embodiment, and the scope of the present invention is not limited thereto. Do. Those skilled in the art to which the present invention pertains will be able to make various applications and modifications within the scope of the present invention based on the above contents.

Therefore, the substantial scope of the present invention will be defined by the appended claims and equivalents thereof.

Claims (13)

As an ionic functional group containing acrylic copolymer manufactured by reaction of the acrylic copolymer containing an epoxy group and the ionic compound containing a carboxylic acid group,
The acrylic copolymer containing the epoxy group is prepared by copolymerization of a (meth) acrylate monomer and a monomer containing an unsaturated double bond and an epoxy group in a molecule at the same time, and a monomer containing the unsaturated double bond and an epoxy group in a molecule at the same time. Is at least one selected from compounds of Formulas 1 to 4,
The ionic compound containing a carboxylic acid group is at least one ionic functional group-containing acrylic copolymer selected from the compounds of formulas 5 to 17:
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

delete delete The ionic functional group-containing acrylic copolymer according to claim 1, wherein the monomer containing an unsaturated double bond and an epoxy group in the molecule is contained in an amount of 1 to 20% by weight based on 100% by weight of the acrylic copolymer containing an epoxy group. delete delete delete delete A method for producing an ionic functional group-containing acrylic copolymer comprising reacting an acrylic copolymer containing an epoxy group with an ionic compound containing a carboxylic acid group,
The acrylic copolymer containing the epoxy group is prepared by copolymerization of a (meth) acrylate monomer and a monomer containing an unsaturated double bond and an epoxy group in a molecule at the same time, and a monomer containing the unsaturated double bond and an epoxy group in a molecule at the same time. Is at least one selected from compounds of Formulas 1 to 4,
The ionic compound containing a carboxylic acid group is a method for producing an ionic functional group-containing acrylic copolymer is one or more selected from compounds of the formula 5 to 17:
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

The process according to claim 9, wherein the reaction is carried out in the presence of a trialkylamine or tetraalkylammonium catalyst. An ionic functional group-containing acrylic copolymer, a crosslinking agent, and a silane coupling agent according to any one of claims 1 and 4, and not containing an ionic compound containing a carboxylic acid group which is not covalently bonded to the acrylic copolymer. Pressure-sensitive adhesive composition. The polarizing plate in which the adhesive layer which consists of an adhesive composition of Claim 11 was laminated | stacked. A liquid crystal display device comprising a polarizing plate according to claim 12 on at least one side of a liquid crystal cell.