KR20130052498A - Adhesive composition, polarizing plate and liquid crystal display device comprising the same - Google Patents

Abstract

The present invention relates to a pressure-sensitive adhesive composition, a polarizing plate and a liquid crystal display device comprising the same, more specifically an acrylic copolymer; A crosslinking agent; And a mixture of an ionic solid represented by the formula (1) and a surfactant containing an alkylene oxide group having 2-4 carbon atoms of the alkylene group as an antistatic agent, thereby ensuring sufficient antistatic properties and maintaining high adhesion even in a small amount. Alternatively, the present invention relates to a pressure-sensitive adhesive composition, a polarizing plate including the same, and a liquid crystal display device, which can prevent degradation of durability even under a high temperature and high humidity environment.

Description

Adhesive composition, polarizing plate and liquid crystal display including the same {ADHESIVE COMPOSITION, POLARIZING PLATE AND LIQUID CRYSTAL DISPLAY DEVICE COMPRISING THE SAME}

The present invention relates to a pressure-sensitive adhesive composition, a polarizing plate and a liquid crystal display including the same, which can secure sufficient antistatic property even in a small amount while maintaining adhesion and durability.

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.

In general, the polarizing plate is a polarizer protective film represented by triacetyl cellulose (TAC) on one surface of a polyvinyl alcohol (PVA) polarizer and a surface protective film is laminated as needed, the polarizer protective film on the other side , A pressure-sensitive adhesive layer and a release film for bonding to the liquid crystal cell is a multi-layer structure laminated in order.

In the process of bonding the polarizing plate having such a structure to the liquid crystal cell, the release film and the surface protection film are peeled off. Since the release film and the surface protection film are made of a plastic material having high electrical insulation, static electricity is generated when the peeling is removed. do. The static electricity generated in this way may cause foreign matter to be adsorbed on the optical member to contaminate the surface, staining due to distortion of the liquid crystal alignment, and damage to the thin film transistor circuit.

In order to solve the above problems, Japanese Patent Laid-Open Publication No. 2006-011365 and Korean Patent Publication No. 2010-0122885 disclose a pressure-sensitive adhesive composition containing an ionic liquid in a liquid state at room temperature. However, ionic liquids have a disadvantage in that ionic liquids are easily leaked to the outside under high temperature or high temperature-humidity environment, and are very expensive due to their structural specificity.

In consideration of this, an ionic solid having a high melting point as an ionic compound at room temperature has been proposed. Japanese Laid-Open Patent Publication No. 2009-001516 discloses a 4-methyl-1-alkylpyridinium hexafluorophosphate salt in which a methyl group is substituted at the para position of pyridine as an ionic compound. However, this salt can cause crystallization under high temperature environment due to the symmetrical structure of pyridine and its durability can be lowered due to aggregation of PF ₆ ⁻ anions.

Japanese Laid-Open Patent No. 2006-011365 (2006.01.12). Korean Patent Publication No. 2010-0122885 (Nov. 23, 2010). Japanese Laid-Open Patent No. 2009-001516 (2009.01.08).

It is an object of the present invention to provide an adhesive composition which can secure antistatic property while maintaining adhesive strength and durability, and can also reduce cost.

In addition, 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.

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.

1.A pressure-sensitive adhesive composition comprising a mixture of a compound containing an ionic solid represented by Formula 1 below and an alkylene oxide group having 2 to 4 carbon atoms of an alkylene group:

Wherein X is an alkali metal.

2. In the above 1, the compound containing an alkylene oxide group having 2 to 4 carbon atoms of the alkylene group is polyethylene glycol polymer, polypropylene glycol polymer, polyethylene glycol-polypropylene glycol copolymer, polypropylene glycol- polyethylene glycol-poly At least one pressure-sensitive adhesive composition selected from the group consisting of a propylene glycol copolymer and a polyethylene glycol-polypropylene glycol-polyethylene glycol copolymer.

3. In the above 1, the mixing ratio of the compound containing an alkylene oxide group having 2 to 4 carbon atoms of the ionic solid and the alkylene group represented by the formula (1) is 1: 0.1 to 1:20 weight ratio of the pressure-sensitive adhesive composition.

4. according to the above 1, the pressure-sensitive adhesive composition comprising an acrylic copolymer and a crosslinking agent.

5. In the above 4, the pressure-sensitive adhesive composition containing 0.1 to 40 parts by weight of the mixed solution based on 100 parts by weight of the acrylic copolymer based on the solid content.

6. In the above 4, the pressure-sensitive adhesive composition containing 0.1 to 15 parts by weight of the crosslinking agent based on 100 parts by weight of the acrylic copolymer based on the solid content.

7. Polarizing plate of the pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition of any one of 1 to 6 above.

8. Liquid crystal display device having a polarizing plate of the above 7 on at least one side of the liquid crystal cell.

The present invention can secure sufficient antistatic properties even if it contains an antistatic agent in a small amount, such as 2/3 less than the mass production that is commonly used, and the compatibility between the components is good, while maintaining the adhesive force at high temperature or high temperature and high humidity It is possible to suppress the outflow and movement of the ionic compound under one environment, thereby preventing the durability decrease.

In addition, the present invention is economical in terms of cost because the antistatic agent can be applied at a price lower than mass production, for example, about 1/20.

The present invention relates to a pressure-sensitive adhesive composition, a polarizing plate and a liquid crystal display including the same, which can secure sufficient antistatic property even in a small amount while maintaining adhesion and durability.

Hereinafter, the present invention will be described in detail.

The pressure-sensitive adhesive composition of the present invention is characterized by comprising a mixture of a compound containing an ionic solid represented by the following formula (1) and an alkylene oxide group having 2 to 4 carbon atoms of an alkylene group:

[Formula 1]

Wherein X is an alkali metal.

More specifically, the pressure-sensitive adhesive composition of the present invention may include a mixture of an acrylic copolymer, a crosslinking agent, and a compound containing an alkylene oxide group having 2 to 4 carbon atoms of an ionic solid represented by Formula 1 and an alkylene group.

The acrylic copolymer may be a copolymer of a monomer having a functional group capable of crosslinking with a (meth) acrylate monomer having an alkyl group having 1 to 12 carbon atoms as an adhesive resin. Here, (meth) acrylate means both acrylate and methacrylate.

As a (meth) acrylate monomer which has a C1-C12 alkyl group, n-butyl (meth) acrylate, 2-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) Acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, methylethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, pentyl (meth) acrylate, n -Octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (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 having an alkyl group having 1 to 12 carbon atoms may be included in an amount of 80 to 99% by weight based on 100% by weight of the total monomers used to prepare the acrylic copolymer, and preferably 90 to 95% by weight. . 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.

The monomer having a crosslinkable functional group is a component for reinforcing the cohesive force or adhesive strength of the pressure-sensitive adhesive composition by chemical bonding to impart durability and cleavage, such as a monomer having a hydroxy group, a monomer having a carboxyl group, a monomer having an amide group, and a tertiary The monomer etc. which have an amine group are mentioned, These can be used individually or in mixture of 2 or more types.

Examples of the monomer having a hydroxy group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl Hydroxypropyleneglycol (meth) acrylate, hydroxyalkylene glycol having 2 to 4 carbon atoms in the alkylene group (e.g., methoxyethyl (meth) acrylate, Hydroxybutyl vinyl ether, 8-hydroxyoctyl vinyl ether, 9-hydroxynonyl (meth) acrylate, 4-hydroxybutyl vinyl ether, Vinyl ether, and 10-hydroxydecyl vinyl ether. Of these, 4-hydroxybutyl vinyl ether is preferable.

Examples of the monomer having a carboxyl group include monovalent acids such as (meth) acrylic acid and crotonic acid; Dicarboxylic acids such as maleic acid, itaconic acid, and fumaric acid, and monoalkyl esters thereof; 3- (meth) acryloylpropionic acid; A succinic anhydride ring-opening addition adduct of 2-hydroxyalkyl (meth) acrylate in which the alkyl group has 2 to 4 carbon atoms, anhydrous succinic ring opening adduct of a hydroxyalkylene glycol (meth) acrylate having 2 to 4 carbon atoms in the alkylene group , Compounds obtained by ring-opening addition of succinic anhydride to caprolactone adducts of 2-hydroxyalkyl (meth) acrylates whose alkyl groups have 2-3 carbon atoms, and among these, (meth) acrylic acid is preferable.

Examples of the monomer having an amide group include (meth) acrylamide, N-isopropyl acrylamide, N-tertiary butyl acrylamide, 3-hydroxypropyl (meth) acrylamide, 4-hydroxybutyl (Meth) acrylamide, 8-hydroxyoctyl (meth) acrylamide and 2-hydroxyethylhexyl (meth) acrylamide. Of these, (meth) acrylamide is preferable.

Examples of the monomer having a tertiary amine group include N, N- (dimethylamino) ethyl (meth) acrylate, N, N- (diethylamino) ethyl (meth) ) Acrylate, and the like.

It is preferable that the monomer which has a crosslinkable functional group is contained in 1 to 10 weight% with respect to 100 weight% of total monomers used for manufacture of an acryl-type copolymer, More preferably, it is 1 to 8 weight%. If the content is less than 1% by weight, the cohesive force of the pressure-sensitive adhesive may be reduced, and the durability may be lowered. If the content is more than 10% by weight, the adhesive strength may be degraded due to a high gel fraction, which may cause problems in durability.

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.

The method for producing the copolymer is not particularly limited and can be produced by methods 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 polymerization can be used.

The copolymer has a weight average molecular weight (polystyrene equivalent, Mw) measured by gel permeation chromatography (GPC) of 50,000 to 2 million, preferably 400,000 to 2 million.

A crosslinking agent is a component for strengthening the cohesion force of an adhesive by crosslinking an acryl-type 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 Diisocyanate compounds such as naphthalene 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 compound 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, trimethylolpropanetriglycidyl 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 is preferably 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 the present invention, a mixed solution of an ionic solid represented by the formula (1) and a compound containing an alkylene oxide group having 2 to 4 carbon atoms of the alkylene group is characterized as an antistatic agent.

The ionic solid represented by the formula (1) is a compound formed by the ionic bonding of a cation with a saccharin anion containing an inert nitrogen, especially in a molecule, and sufficient antistatic property can be secured even if a small amount of about 2/3 of the mass product is added. In addition, the price is also about 1/20 of the mass-produced product can reduce the cost.

[Formula 1]

In the formula, X is an alkali metal, preferably Li, Na, K, and more preferably Na.

The ionic solid represented by Formula 1 has poor solubility because of poor compatibility with other components of the pressure-sensitive adhesive composition. Accordingly, in the present invention, a compound containing an alkylene oxide group having 2 to 4 carbon atoms of an alkylene group is used in combination to dissolve the ionic solid, thereby improving compatibility and imparting stability to the pressure-sensitive adhesive composition.

The kind of the compound containing the alkylene oxide group having 2-4 carbon atoms of the alkylene group is not particularly limited, and the polyester polymer containing the ethylene oxide group has good compatibility with the acrylic copolymer which is the main component of the pressure-sensitive adhesive composition. Preferred at Examples thereof include polyethylene glycol polymers, polypropylene glycol polymers, polyethylene glycol-polypropylene glycol copolymers, polypropylene glycol-polyethylene glycol-polypropylene glycol copolymers, polyethylene glycol-polypropylene glycol-polyethylene glycol copolymers, and the like. These compounds may be the end of the glycol chain is substituted with an alkyl group or phenyl group having 1 to 20 carbon atoms, the number of moles of alkylene oxide can be selected in the appropriate range. These can be used individually or in mixture of 2 or more types. Moreover, the product containing the alkylene oxide group of 2-4 carbon atoms of an alkylene group can also be used as a commercially available surfactant.

The compound containing an alkylene oxide group having 2 to 4 carbon atoms of the ionic solid represented by Formula 1 and the alkylene group may be mixed in a weight ratio of 1: 0.1 to 1:20, preferably 1: 1 to 1: It is good to mix in 17 weight ratio. When the weight ratio is less than 1: 0.1, that is, the compound is less than 0.1 part by weight based on 1 part by weight of the ionic solid, the ionic solid may not be sufficiently dissolved, and the effect of improving compatibility with other components of the pressure-sensitive adhesive composition may be insignificant. In addition, durability may be lowered if the weight ratio is greater than 1:20, that is, the compound is more than 20 parts by weight based on 1 part by weight of the ionic solid.

The mixture of the ionic solid represented by the formula (1) and the compound containing an alkylene oxide group having 2-4 carbon atoms of the alkylene group is preferably included in an amount of 0.1 to 40 parts by weight based on 100 parts by weight of the acrylic copolymer based on the solid content. Do. If the content is less than 0.1 parts by weight, it may be difficult to obtain sufficient antistatic properties, and if it exceeds 40 parts by weight, bubbles or peeling may occur and durability may be reduced.

The pressure-sensitive adhesive composition may further include a silane coupling agent.

The kind of the silane coupling agent is not particularly limited, and for example, vinylchlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxy Propyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-metha Krilloxypropyl triethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyl diethoxysilane, 3-acryloxypropyl trimethoxysilane , N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyl Methyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyl Dimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatepropyltriethoxysilane, and the like. These can be used individually or in mixture of 2 or more types.

The silane coupling agent may be included in an amount of 0 to 10 parts by weight based on 100 parts by weight of the copolymer based on the solid content, preferably 0.005 to 5 parts by weight. If the content is more than 10 parts by weight, durability may be reduced.

In addition to the above components, the pressure-sensitive adhesive composition is a tackifying resin, antioxidant, corrosion inhibitor, leveling agent, surface lubricant, dye, pigment in order to adjust the adhesion, cohesion, viscosity, modulus, glass transition temperature, etc. required according to the application It may further include additives such as antifoaming agent, filler, light stabilizer.

The pressure-sensitive adhesive composition is prepared by dissolving an ionic solid represented by Chemical Formula 1 in a compound containing an alkylene oxide group having 2 to 4 carbon atoms of an alkylene group to prepare a mixed solution; And it may be prepared by a method comprising the step of mixing an acrylic copolymer, a crosslinking agent and the prepared liquid mixture. More specifically, first, the ionic solid represented by Formula 1 having poor compatibility with the constituents included in the pressure-sensitive adhesive composition is mixed with a compound containing an alkylene oxide group having 2-4 carbon atoms in the alkylene group to dissolve it. Prepare the mixed solution. The prepared liquid mixture is incompatible with the components Outflow and migration of ionic compounds can be suppressed. Then, the pressure-sensitive adhesive composition can be prepared by mixing the acrylic copolymer, the crosslinking agent and the prepared liquid mixture in a conventional manner.

The pressure-sensitive adhesive composition thus constructed and prepared includes a mixture of an ionic solid represented by Formula 1 and a compound containing an alkylene oxide group having 2 to 4 carbon atoms of an alkylene group as an antistatic agent, thereby providing compatibility between components. Good antistatic and adhesive durability can be secured, and the effect can be achieved in a small amount, and the cost can be greatly reduced.

The pressure-sensitive adhesive composition of the present invention can be used both as a pressure-sensitive adhesive for surface protection film as well as pressure-sensitive adhesive for polarizing plate 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.

The polarizing plate of the present invention is characterized in that an adhesive layer made of an adhesive composition is laminated.

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

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

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but these examples are merely illustrative of the present invention and are not intended to limit the scope of the appended claims. It is apparent to those skilled in the art that various changes and modifications can be made to the present invention, and such modifications and changes belong to the appended claims.

Example

Manufacturing example  1. Acrylic Copolymer Preparation

98.1 parts by weight of n-butyl acrylate (BA), 0.5 parts by weight of acrylic acid (AA), 2-hydroxyethyl methacrylate (HEMA) 1.4 After adding a monomer mixture consisting of parts by weight, 100 parts by weight of ethyl acetate (EA) was added as a solvent. Thereafter, nitrogen gas was added for 1 hour to remove oxygen, and then the temperature was maintained at 62 ° C. After stirring the monomer mixture uniformly, 0.07 parts by weight of azobisisobutyronitrile (AIBN) was added as a reaction initiator and reacted for 8 hours to prepare an acrylic copolymer having a weight average molecular weight of 600,000 or more.

Example  One

(1) pressure-sensitive adhesive composition

First, saccharin sodium (SS) and polyethylene glycol (PEG) polymers were mixed in a weight ratio of 1: 2 to prepare an antistatic agent solution.

Then, 100 parts by weight of the acrylic copolymer of Preparation Example 1, 0.5 parts by weight of tolylene diisocyanate adduct of trimethylolpropane (Cor-L, Japan Polyurethane Industry), 3 parts by weight of the antistatic agent solution prepared, 3-glyci A pressure-sensitive adhesive composition was prepared by mixing 0.2 parts by weight of doxypropyltrimethoxysilane (KBM-403, Shin-Etsu) and diluting to a proper concentration in consideration of coating properties.

(2) adhesive sheet

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

(3) polarizing plate with pressure-sensitive adhesive

After peeling the release film of the prepared pressure-sensitive adhesive sheet, the pressure-sensitive adhesive layer was laminated on an iodine-based polarizing plate having a thickness of 185 μm to prepare a polarizing plate with pressure-sensitive adhesive.

Example  2-6, Comparative example  1-3

The same procedure as in Example 1, except that the ingredients and contents as shown in Table 1 were used. At this time, the content is parts by weight.

division Copolymer Cross-linking agent Antistatic agent Silane coupling agent COR-L Kinds Mixing ratio content KBM-403 Example 1 100 0.5 SS / PEG 1: 2 3 0.2 Example 2 100 0.5 SS / PEG 1: 5 3 0.2 Example 3 100 0.5 SS / PEG 1: 5 5 0.2 Example 4 100 0.5 SS / PEG 1:15 3 0.2 Example 5 100 0.5 SS / PEG 1: 0.5 3 0.2 Example 6 100 0.5 SS / PEG 1:25 3 0.2 Comparative Example 1 100 0.5 SS - 0.5 0.2 Comparative Example 2 100 0.5 SS - 0.5 0.2 Comparative Example 3 100 0.5 OMPHFPh - 0.5 0.2 COR-L: tolylene diisocyanate adduct of trimethylolpropane (Japan Polyurethane Industry)
SS: Saccharin Sodium
PEG: polyethylene glycol polymer
OMPHFPh: 1-octyl-4-methylpyridinium hexafluorophosphate

Test Example

The physical properties of the pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet and 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. Antistatic property (surface specific resistance)

After peeling the release film of the prepared pressure-sensitive adhesive polarizing plate using a surface resistance measuring instrument (MCP-HT450, Mitsubishi Chemical, Probe: URS, UR100, Probe checker: for URS, UR100) to each of the three points of the adhesive layer 10 After measuring once, the average value was calculated and evaluated based on the following criteria.

<Evaluation Criteria>

Ⓞ: Surface resistivity ≤ 5.0 × 10 ¹⁰ Ω / □

○: 5.0 × 10 ¹⁰ Ω / □ <surface specific resistance ≤ 9.0 × 10 ¹⁰ Ω / □

△: 9.0 × 10 ¹⁰ Ω / □ <surface specific resistance ≤ 1.0 × 10 ¹¹ Ω / □

×: 1.0 × 10 ¹¹ Ω / □ <surface specific resistance

2. Compatibility

After curing the prepared pressure-sensitive adhesive sheet, the appearance was confirmed and evaluated based on the following criteria.

<Evaluation Criteria>

(Circle): An antistatic agent does not precipitate on the adhesive sheet surface.

(Triangle | delta): A small amount of antistatic agent precipitates on the adhesive sheet surface.

X: An antistatic agent precipitates in large quantities on the adhesive sheet surface.

3. Adhesion

The prepared polarizer with a pressure-sensitive adhesive was cut into a size of 25 mm x 100 mm, and the release film was peeled off. The release film was laminated to a glass substrate (# 1737, Corning) at a pressure of 0.25 MPa and autoclaved. After room temperature adhesiveness was left for 24 hours under 23 ° C and 50% RH, the warm adhesive strength was measured after 48 hours under 50 ° C and 50% RH, and then the universal tensile tester (UTM, Instron) was used. The pressure-sensitive adhesive layer was peeled off at a peeling rate of 300 mm / min and a peeling angle of 180 °, and measured. At this time, measurement was carried out under conditions of 23 캜 and 50% RH.

<Evaluation Criteria>

○: 3.0 N / 25 mm ≤ adhesive force

Δ: 1.5 N / 25 mm ≤ adhesive force <3.0 N / 25 mm

×: adhesive force <1.5 N / 25 mm

4. Durability (heat resistant, Wet heat )

The prepared polarizer with a pressure-sensitive adhesive was cut into a size of 90 mm × 170 mm, and the release film was peeled off. Then, the optical absorption axis was perpendicularly attached to both sides of the glass substrate (110 mm × 190 mm × 0.7 mm). At this time, the applied pressure was 5 kg / cm &lt; 2 &gt;, and the clean room operation was performed so that bubbles or foreign matter would not occur. The heat resistance was observed for 1000 hours at the temperature of 80 ℃ after the occurrence of bubbles or peeling. At this time, it was observed after leaving for 24 hours at room temperature immediately before evaluating the state of the specimen.

<Evaluation Criteria>

Ⓞ: No bubbles, no peeling phenomenon.

○: bubbles <5, no peeling phenomenon.

△: 5 ≤ bubbles <10 or peeling phenomenon.

X: 10 <bubble, peeling and lifting phenomenon by precipitation of antistatic agent.

division Antistatic Compatibility adhesiveness durability Heat resistance Wet heat Example 1 ◎ ○ ○ ◎ ○ Example 2 ○ ○ ○ ◎ ○ Example 3 ◎ ○ △ ○ ○ Example 4 ○ ○ △ ○ ○ Example 5 ◎ △ △ ○ ○ Example 6 △ ○ △ △ ○ Comparative Example 1 ○ X ○ X X Comparative Example 2 ○ X ○ X X Comparative Example 3 ○ ○ ○ X ○

As shown in Table 2, the pressure-sensitive adhesive of Examples 1 to 6 comprising a mixture of a compound containing an alkylene oxide group having 2 to 4 carbon atoms of the ionic solid and the alkylene group represented by the formula (1) according to the present invention The composition has good compatibility compared to the pressure-sensitive adhesive compositions of Comparative Examples 1 to 3, it is possible to obtain sufficient antistatic properties even in the small amount of the antistatic agent, it was confirmed that the adhesive strength and durability is also good. In particular, when the mixing ratio of the ionic solid represented by the formula (1) and the surfactant containing an alkylene oxide group having 2 to 4 carbon atoms of the alkylene group is 1: 1 to 1:20 can obtain a good effect in terms of all physical properties Preferred. In addition, the cost was reduced by more than 1/10.

Claims (8)

Pressure-sensitive adhesive composition comprising a mixture of a compound containing an ionic solid represented by the formula (1) and an alkylene oxide group having 2 to 4 carbon atoms of the alkylene group:
[Formula 1]

Wherein X is an alkali metal.
The compound according to claim 1, wherein the compound containing an alkylene oxide group having 2-4 carbon atoms in the alkylene group is a polyethylene glycol polymer, a polypropylene glycol polymer, a polyethylene glycol-polypropylene glycol copolymer, a polypropylene glycol-polyethylene glycol-polypropylene glycol At least one adhesive composition selected from the group consisting of a copolymer and a polyethylene glycol-polypropylene glycol-polyethylene glycol copolymer.
The pressure-sensitive adhesive composition of claim 1, wherein a mixing ratio of the ionic solid represented by the following formula (1) and the compound containing an alkylene oxide group having 2-4 carbon atoms in the alkylene group is in a weight ratio of 1: 0.1 to 1:20.
The pressure-sensitive adhesive composition of claim 1, comprising an acrylic copolymer and a crosslinking agent.
The pressure-sensitive adhesive composition of claim 4, comprising 0.1 to 40 parts by weight of the mixed solution based on 100 parts by weight of the acrylic copolymer based on the solid content.
The pressure-sensitive adhesive composition of claim 4, comprising 0.1 to 15 parts by weight of a crosslinking agent based on 100 parts by weight of the acrylic copolymer based on the solid content.
The polarizing plate in which the adhesive layer which consists of an adhesive composition of any one of Claims 1-6 was laminated | stacked.
A liquid crystal display device comprising the polarizing plate of claim 7 on at least one side of a liquid crystal cell.