KR20140086658A - Copolymer and Pressure-sensitive adhesive composion comprising the same - Google Patents

Abstract

The present invention relates to a co-polymer capable of providing a pressure-sensitive adhesive composition with improved antistatic properties and durability, and the pressure-sensitive adhesive composition comprising the same. The present invention relates to an acrylic co-polymer with improved antistatic properties and durability by including a repeating unit which is formed as ionic monomers containing a vinyl group and a silyl group.

Description

Copolymer and Pressure-Sensitive Adhesive Composition "

The present invention relates to a copolymer capable of providing a pressure-sensitive adhesive composition having improved antistatic properties and durability, and a pressure-sensitive adhesive composition comprising the same.

An image display apparatus using a liquid crystal includes a liquid crystal cell and a liquid crystal panel including a polarizing plate bonded to both surfaces of the liquid crystal cell via an adhesive layer.

When the releasing film is peeled off from the pressure-sensitive adhesive layer in the process of attaching the polarizing plate to the liquid crystal cell, static electricity is generated, and the generated static electricity affects the orientation of the liquid crystal to cause defects or to be introduced between the liquid crystal cell and the pressure- It causes pollution by foreign matter.

In order to solve this problem, an antistatic agent is mixed with the pressure-sensitive adhesive, but bleed-out phenomenon deposited on the surface of the antistatic agent may cause lifting, bubbling and peeling. In particular, such problems can be exacerbated by exposure to high temperature or high temperature and high humidity environments.

Korean Patent Laid-Open Publication No. 2009-132564 discloses a pressure-sensitive adhesive composition having increased compatibility with a base resin by using an ionic liquid as an antistatic agent. However, the above method is still insufficient to improve the durability due to the bleed-out phenomenon.

On the other hand, the pressure-sensitive adhesive must basically have excellent adhesion to a substrate. Such adhesive force is determined depending on the type of resin used in the pressure-sensitive adhesive, but in some cases, the lack of adhesive strength may be compensated by using a silane coupling agent.

Patent Document 1: Korean Patent Publication No. 2009-132564

An object of the present invention is to provide a copolymer that can be used in a pressure-sensitive adhesive capable of preventing bleed-out phenomenon while having antistatic properties.

It is another object of the present invention to provide a copolymer which can be used in a pressure-sensitive adhesive excellent in adhesion.

Another object of the present invention is to provide a pressure sensitive adhesive comprising the copolymer as described above, a polarizing plate using the same, and an image display device.

1. An acrylic copolymer comprising a repeating unit formed from an ionic monomer containing a vinyl group and a silyl group.

2. The acrylic copolymer according to claim 1, wherein the ionic monomer having a vinyl group and a silyl group is a monomer represented by the following Formula 1:

[Chemical Formula 1]

(Wherein, R ₁ is a fluorine ion, iodine ion, fluorine-containing anion, or an iodine-containing anion; R ₂ is an alkylene group of a carbon number of 1 to _{12; R 3, R 4,} R 5 are independently a carbon number of 1 to each other Lt; / RTI >

3. The copolymer according to claim 1, wherein the copolymer is formed by copolymerization of a (meth) acrylate monomer containing an alkyl group having 1 to 12 carbon atoms and a monomer represented by the formula (1).

4. The copolymer according to claim 3, wherein the copolymer is formed by polymerizing 100 parts by weight of a (meth) acrylate monomer containing an alkyl group having 1 to 12 carbon atoms and 0.01 to 20 parts by weight of a monomer represented by the formula (1).

5. The composition of claim 3, wherein the (meth) acrylate monomer is selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate, methylethyl (meth) acrylate, Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, (Meth) acrylate, n-octyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl Lauryl (meth) acrylate, and mixtures thereof.

6. The copolymer according to claim 1, further comprising a monomer having a crosslinkable functional group.

7. The copolymer according to claim 6, wherein the crosslinkable functional group is a hydroxyl group, a carboxyl group, an amide group or a tertiary amine group.

8. The copolymer according to claim 6, wherein the monomer having a crosslinkable functional group is contained in an amount of 0.1 to 15% by weight based on the total weight of the total monomers.

9. The copolymer according to claim 1, having a weight average molecular weight of 50,000 to 2,000,000.

10. A pressure-sensitive adhesive composition comprising a copolymer according to any one of claims 1 to 9 and a crosslinking agent.

11. The pressure-sensitive adhesive composition according to claim 10, wherein the cross-linking agent is contained in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the solid content of the copolymer.

12. A polarizer plate comprising a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition of claim 10.

13. An image display apparatus comprising the polarizing plate of claim 12.

The copolymer of the present invention contains both a vinyl group and a silyl group, and by using an ionic monomer, the copolymer itself has antistatic properties and a durability improvement function due to silyl groups.

Since the copolymer of the present invention has an antistatic property, it is possible to produce a pressure-sensitive adhesive having antistatic property without using it in combination with another antistatic agent, or to add only a small amount of the pressure- Out phenomenon can be prevented.

In addition, since the copolymer of the present invention has a silyl group and its tackiness is improved, a tackiness agent having excellent tackiness can be produced even if it is not used in combination with a separate silane coupling agent or only a small amount is added.

The present invention relates to an acrylic copolymer improved in antistatic property and adhesiveness by containing a repeating unit formed from an ionic monomer containing a vinyl group and a silyl group.

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

The acrylic copolymer of the present invention comprises a repeating unit formed from an ionic monomer containing a vinyl group and a silyl group. The ionicity of the repeating unit makes the copolymer antistatic, and the silyl group imparts adhesiveness of the silane coupling agent to the copolymer of the present invention.

Since the copolymer of the present invention contains both a functional group exhibiting antistatic properties and a functional group (silyl group) improving the adhesiveness within the structure of the copolymer, the use of another antistatic agent or a silane coupling agent when used as a pressure- Can be excluded. Needless to say, the use of a small amount of an antistatic agent or a silane coupling agent according to need is not completely excluded.

The structure of the ionic monomer containing a vinyl group and a silyl group according to the present invention is not particularly limited as long as it contains a silyl group and a vinyl group for polymerization as an ionic monomer. As specific examples, monomers represented by the following formula (1) may be used:

[Chemical Formula 1]

(Wherein, R ₁ is a fluorine ion, iodine ion, fluorine-containing anion, or an iodine-containing anion; R ₂ is an alkylene group of a carbon number of 1 to _{12; R 3, R 4,} R 5 are independently a carbon number of 1 to each other Lt; / RTI >

The acrylic copolymer of the present invention can be formed by copolymerizing the monomer of Formula 1 with (meth) acrylate monomer, wherein the (meth) acrylate monomer forms the main structure of the copolymer and exhibits stickiness. (Meth) acrylate monomer is preferably a (meth) acrylate monomer containing an alkyl group having 1 to 12 carbon atoms.

When the monomer of the formula (1) of the present invention is copolymerized with a (meth) acrylate monomer containing an alkyl group having 1 to 12 carbon atoms, the monomer represented by the formula (1) 20 to 20 parts by weight, preferably 0.1 to 15 parts by weight, to form a copolymer. It is possible to exhibit excellent adhesion and cohesive force in the above content range.

Specific examples of the (meth) acrylate monomer having an alkyl group having 1 to 12 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, methylethyl (meth) (Meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, (Meth) acrylate, n-octyl (meth) acrylate, n-octyl (meth) acrylate, n-octyl ) Acrylate, lauryl (meth) acrylate, etc. may be used alone or in combination of two or more.

Alternatively, the copolymer of the present invention may further comprise a monomer having a crosslinkable functional group. The monomer having a crosslinkable functional group is a component for imparting durability and cutability by reinforcing the cohesive strength or adhesive strength of the pressure-sensitive adhesive composition by chemical bonding, and examples thereof include monomers having a hydroxy group, monomers having a carboxyl group, monomers having an amide group, And amine group-containing monomers. These monomers may be used alone or in admixture of two or more, preferably monomers having a hydroxy group.

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.

The monomer having a crosslinkable functional group may be contained in an amount of 0.1 to 15% by weight, more preferably 1 to 10% by weight based on the total weight of the total monomers. The cohesive force, adhesive strength and durability of the pressure-sensitive adhesive can be excellently exerted in the above-mentioned content range.

In addition, other polymerizable monomers other than the above-mentioned monomers may be further added in such a range as not to lower the adhesive force, for example, 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 may have a weight average molecular weight (polystyrene conversion, Mw) of 50,000 to 2,000,000, preferably 100,000 to 100, as measured by gel permeation chromatography (GPC). The cohesive force and the adhesion durability between the copolymers can be excellently exhibited without requiring a large amount of a diluting solvent in the molecular weight range.

The copolymer of the present invention can be mixed with a crosslinking agent and used as a pressure-sensitive adhesive composition.

The crosslinking agent is a component for reinforcing the cohesive force of the pressure-sensitive adhesive by properly crosslinking the copolymer, and the kind thereof is not particularly limited. Examples thereof include isocyanate compounds and epoxy compounds, which may be used alone or in combination of two or more.

Examples of the isocyanate compound include 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; An adduct obtained by reacting 3 moles of a diisocyanate compound with 1 mole of a polyhydric alcohol compound such as trimethylolpropane, an isocyanurate compound in which 3 moles of a diisocyanate compound is self-condensed, a diisocyanate obtained from 2 moles of 3 moles of a diisocyanate compound And multifunctional isocyanate compounds containing three functional groups such as burette, triphenylmethane triisocyanate and methylene bistriisocyanate in which the remaining one mole of diisocyanate is condensed in 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, polypropylene glycol Hexanediol diglycidyl ether, polytetramethylene glycol diglycidyl ether, glycerol diglycidyl ether, glycerol triglycidyl ether, glycerol diglycidyl ether, glycerol diglycidyl ether, Diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, resorcinol 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) isocyanurate N, N ', N'-tetraglycidyl-m-glycidoxyethyl isocyanurate, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, Xylylenediamine, and the like.

In addition, an isocyanate compound, an epoxy compound, and a melamine compound may be used alone or in admixture of two or more.

Examples of the melamine-based compound include hexamethylol melamine, hexamethoxymethyl melamine, and hexabutoxymethyl melamine.

The crosslinking agent is preferably contained in an amount of 0.1 to 15 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the copolymer based on the solid content. It is possible to exhibit a suitable degree of crosslinking that is not excessively crosslinked in the above content range and can exhibit necessary cohesive strength.

In addition to the above-mentioned components, the pressure-sensitive adhesive composition according to the present invention may further contain additives such as a tackifier resin, an antioxidant, a corrosion inhibitor, a leveling agent, a surface lubricant, , Dyes, pigments, defoamers, fillers, light stabilizers, and the like. In addition, as described above, the pressure-sensitive adhesive of the present invention may further contain a small amount of an antistatic agent and a silane coupling agent, if necessary, within the scope of the present invention, if necessary.

The pressure-sensitive adhesive composition of the present invention can be used not only as a pressure-sensitive adhesive for a polarizing plate for bonding with a liquid crystal cell but also as a pressure-sensitive adhesive for a surface protective film. In addition, it can be used not only as a protective film, a reflective sheet, a structural adhesive sheet, a photographic adhesive sheet, a lane marking adhesive sheet, an optical adhesive product, an electronic component adhesive, but also a general commercial adhesive sheet product or a medical patch.

The polarizing plate of the present invention is characterized in that a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive composition is laminated.

The thickness of the pressure-sensitive adhesive layer can be adjusted in accordance with the adhesive strength, and is preferably 3 to 100 탆, more preferably 10 to 100 탆.

Such a polarizing plate can be applied to all ordinary image display devices, and specifically, a liquid crystal display device including a liquid crystal panel in which a polarizing plate in which a pressure-sensitive adhesive layer is laminated is bonded to at least one surface of a liquid crystal cell can be constituted.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to be illustrative of the invention and are not intended to limit the scope of the claims. It will be apparent to those skilled in the art that such variations and modifications are within the scope of the appended claims.

Manufacturing example  One

85 parts by weight of n-butyl acrylate (BA), 8 parts by weight of methyl acrylate (MA), and 2.0 parts by weight of 2-hydroxyethyl acrylate (weight ratio) were added to a 1 L reactor equipped with a cooling device, And 5 parts by weight of an ionic monomer having the formula (R ₁ = PF ₆ ^- , R ₂ = ^- C ₄ H ₈ -, and R 3 = R 4 = R 5 = -CH ₃ ) 100 parts by weight. Nitrogen gas was then purged for 1 hour to remove oxygen and then maintained at 62 ° C. After the mixture was homogenized, 0.07 part by weight of azobisisobutyronitrile (AIBN) was added as a reaction initiator and reacted for 6 hours to prepare an acrylic copolymer having a weight average molecular weight of about 1,000,000.

Manufacturing example  2

An acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that 90 parts by weight of n-butyl acrylate (BA) was used without using the monomer represented by the general formula (1).

Manufacturing example  3

n- butyl acrylate (BA) 89.95 parts by weight of methyl acrylate (MA) 8 parts by weight of 2-hydroxy ethyl acrylate, 2.0 parts by weight of the formula ^{_{1 (R 1 = PF 6 -}} , R2 = -C 4 H 8 -, and R ₃ = R ₄ = R ₅ = -CH- ₃ ) was used in place of the monomer mixture prepared in Preparation Example 1. The acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that the monomer mixture was used.

Manufacturing example  4

n- butyl acrylate (BA) 89 parts by weight of methyl acrylate (MA) 8 parts by weight of 2-hydroxy ethyl acrylate, 2.0 parts by weight of the formula ^{_{1 (R 1 = PF 6 -}} , R 2 = -C 4 H ₈ -, R ₃ = R ₄ = R ₅ = -CH- ₃ ) was used in place of the monomer mixture prepared in Preparation Example 1, and an acrylic copolymer was prepared in the same manner as in Preparation Example 1.

Manufacturing example  5

n- butyl acrylate (BA) 81 parts by weight of methyl acrylate (MA) 8 parts by weight of 2-hydroxy ethyl acrylate, 2.0 parts by weight of the formula ^{_{1 (R 1 = PF 6 -}} , R2 = -C 4 H 8 -, R ₃ = R ₄ = R ₅ = -CH- ₃ ) was used in place of the monomer mixture prepared in Preparation Example 1, and an acrylic copolymer was prepared in the same manner as in Preparation Example 1.

Manufacturing example  6

n- butyl acrylate (BA) 75 parts by weight of methyl acrylate (MA) 8 parts by weight of 2-hydroxy ethyl acrylate, 2.0 parts by weight of the formula ^{_{1 (R 1 = PF 6 -}} , R2 = -C 4 H 8 -, and R ₃ = R ₄ = R ₅ = -CH- ₃ ) was used in place of the monomer mixture prepared in Preparation Example 1, and an acrylic copolymer was prepared in the same manner as in Preparation Example 1.

Manufacturing example  7

An acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that 5 parts by weight of acrylamide was used instead of the ionic monomer of the formula (1).

Manufacturing example  8

An acrylic copolymer was prepared in the same manner as in Preparation Example 1, except that 5 parts by weight of methoxyethyl acrylate was used instead of the ionic monomer of the formula (1).

Example  1-8 and Comparative Example  1-4

An acrylic copolymer, an ionic antistatic agent, a silane coupling agent and a crosslinking agent were mixed as shown in Table 1, and then 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 silicone release agent to a thickness of 25 탆 and dried at 100 캜 for 1 minute to form an adhesive layer.

The pressure-sensitive adhesive layer prepared above was laminated to an iodine-based polarizing plate having a thickness of 185 μm by pressure-sensitive adhesive processing to produce a polarizer with a pressure-sensitive adhesive.

Test Example

The prepared polarizing plate was stored for 20 days under conditions of 23 캜 and 60% RH.

The following tests were carried out on the pressure-sensitive adhesive and the polarizing plate of the prepared examples and comparative examples, and the results are shown in Tables 2 and 3.

1. Surface resistivity (Ω / □)

The prepared polarizer plate with a pressure-sensitive adhesive was measured 10 times at three points of the pressure-sensitive adhesive layer using a surface resistance meter (MCP-HT450, Mitsubishi Chemical Co., Ltd.) and expressed as an average value thereof.

Thereafter, the polarizing plate with a pressure-sensitive adhesive was allowed to stand at 60 DEG C for 24 hours and then measured in the same manner as above.

2. Heat resistance / Humidity Durability

The release film of the polarizing plate with a pressure-sensitive adhesive was peeled off, and the surface of the pressure-sensitive adhesive layer was bonded with Corning glass. After leaving for 300 hours at 80 캜 (heat resistance) / 60 캜 and 90RH% (humidity and humidity resistance), appearance was confirmed.

<Evaluation Criteria>

Bubbles and peeling phenomenon are observed: x

Bubble or peeling phenomenon is slightly observed, but polarizer performance is maintained: ○

Bubbles and peeling phenomenon are observed: ◎

division Surface resistivity
(Ω / □) Heat resistance Humidity Durability Example 1 1 x 10 ⁹ ◎ ◎ Example 2 3 × 10 ¹⁰ ◎ ◎ Example 3 3 × 10 ⁹ ◎ ◎ Example 4 1 x 10 ⁹ ◎ ◎ Example 5 1 x 10 ⁹ ◎ ◎ Example 6 1 x 10 ⁹ ◎ ◎ Example 7 4 × 10 ¹⁰ ○ ◎ Example 8 2 × 10 ¹⁰ ◎ ○ Comparative Example 1 5 × 10 ¹⁰ × × Comparative Example 2 7 x 10 ⁹ × ○ Comparative Example 3 6 × 10 ⁹ × ○

Table 2 shows that the antistatic property and the adhesive strength were improved because the copolymer in which the polarizer of the examples formed the pressure sensitive adhesive had an ionic and silyl groups and the surface resistivity was lower than that of the comparative examples and the heat resistance and wet heat resistance properties I can confirm that it is excellent.

3. Adhesion (N / 25 mm)

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. The adhesive strength at room temperature was measured by peeling the pressure-sensitive adhesive layer at a peeling speed of 300 mm / min and a peeling angle of 180 ° using a universal tensile tester (UTM, Instron) after the prepared specimen was left under the conditions of 23 ° C. and 50% RH for 24 hours Respectively. At this time, measurement was carried out under conditions of 23 캜 and 50% RH.

The results are shown in Table 3 below.

4. Adhesion durability

The polarizing plate with a pressure-sensitive adhesive was cut into a size of 90 mm x 170 mm and the release film was peeled off. The polarizing plate was attached to both sides of a glass substrate (110 mm x 190 mm x 0.7 mm) such that the absorption axes of the respective polarizing plates were orthogonal. At this time, the applied pressure was 5 kg / cm ² , and a clean room operation was performed so that bubbles or foreign matter would not be generated.

The heat resistance of the specimen was maintained at a temperature of 80 ° C for 1000 hours, and then the occurrence of bubbles or peeling was observed. The specimens were allowed to stand at room temperature for 24 hours immediately before evaluating the state of the specimens. The moisture resistance characteristics of the specimens were observed for 1000 hours under the conditions of a temperature of 60 ° C and a humidity of 90% RH, and then the occurrence of bubbles or peeling was observed.

The results are shown in Table 3 below.

<Evaluation Criteria>

No bubble or peeling: ⓞ

Less than 5 bubbles or peeling: ○

Bubbles or exfoliation Less than 5: Less than 10

10 or more bubbles or peeling: x

5. Process stability (after drying process) Silane system  Compound Remaining rate )

 The adhesive layer dried for 1 minute and 5 minutes, respectively, was dissolved in methyl ethyl ketone and analyzed by LC to determine the residual silane coupling agent content. The residual ratio [residual ratio = (amount of silane coupling agent remaining after drying / Ring agent content) x 100], and the results are shown in Table 3 below.

However, in the case of Examples 8 to 11, since the silyl group was included as a functional group of the copolymer without adding a separate silane coupling agent, the residual ratio was 100%.

division Drying conditions
(minute) adhesiveness
(N / 25 mm) Adhesive durability Process stability Heat resistance Humidity Durability Example 8 One 3.1 ○ ○ 100 5 3.3 ○ ○ 100 Example 9 One 3.2 ○ ○ 100 5 3.0 ○ ○ 100 Example 10 One 3.2 ○ ○ 100 5 3.2 ○ ○ 100 Example 11 One 3.3 ○ ○ 100 5 3.1 ○ ○ 100 Comparative Example 4 One 4.5 ○ ○ 50 5 6.0 ○ × 10 Comparative Example 5 One 4.7 ○ ○ 40 5 7.0 △ × 5

Referring to Table 3, in Examples 8-11, since the silyl group is chemically bonded to the copolymer, the adhesive force is not changed even if the drying conditions change, and the adhesive performance is very stable. However, in the case of Comparative Example 4-5, the silane coupling agent was separately added and mixed, and it was confirmed that the adhesive force was unstable due to the evaporation of the silane coupling agent or the like depending on the drying conditions.

In addition, in Examples 8 to 11, the adhesive strength was adequate to repeatedly attach and detach, whereas in Comparative Example 4-5, the adhesive force was too high in 5 minutes of drying condition, so repeated attachment and detachment was not easy.

It is also confirmed that the adhesion durability and the process stability are remarkably excellent as compared with the comparative examples.

Claims (13)

An acrylic copolymer comprising a repeating unit formed from an ionic monomer containing a vinyl group and a silyl group.
The acrylic copolymer according to claim 1, wherein the ionic monomer having vinyl and silyl groups is a monomer represented by the following formula (1)
[Chemical Formula 1]

(Wherein, R ₁ is a fluorine ion, iodine ion, fluorine-containing anion, or an iodine-containing anion; R ₂ is an alkylene group of a carbon number of 1 to _{12; R 3, R 4,} R 5 are independently a carbon number of 1 to each other Lt; / RTI &gt;
The copolymer according to claim 1, wherein the copolymer is formed by copolymerization of a (meth) acrylate monomer containing an alkyl group having 1 to 12 carbon atoms and a monomer represented by the formula (1).
The copolymer according to claim 3, wherein the copolymer is formed by polymerizing 100 parts by weight of a (meth) acrylate monomer containing an alkyl group having 1 to 12 carbon atoms and 0.01 to 20 parts by weight of a monomer represented by the formula (1).
[4] The method of claim 3, wherein the (meth) acrylate monomer is at least one monomer selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate, methylethyl (meth) acrylate, Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, (Meth) acrylate, n-octyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (Meth) acrylate.
The copolymer according to claim 1, further comprising a monomer having a crosslinkable functional group.
The copolymer according to claim 6, wherein the crosslinkable functional group is a hydroxyl group, a carboxyl group, an amide group or a tertiary amine group.
[Claim 7] The copolymer according to claim 6, wherein the monomer having a crosslinkable functional group is contained in an amount of 0.1 to 15% by weight based on the total weight of the total monomers.
The copolymer according to claim 1, which has a weight average molecular weight of 50,000 to 2,000,000.
A pressure-sensitive adhesive composition comprising the copolymer of any one of claims 1 to 9 and a crosslinking agent.
The pressure-sensitive adhesive composition according to claim 10, wherein the cross-linking agent is contained in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the solid content of the copolymer.
A polarizer comprising a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition of claim 10.
An image display apparatus comprising the polarizing plate of claim 12.