KR20150085971A - Adhesive Composition and Polarizing Plate Comprising the Same - Google Patents

Abstract

Provided in the present invention are an adhesive composition including a compound having a hydrogen bonding functional group with a primary or secondary amino group, and a polyvinyl alcoholic resin, and a polarizing plate and a liquid crystal display device including the same. The adhesive composition according to the present invention not only improves adhesion to a film having an ester group, but also has excellent heat resistance and moist heat resistance.

Description

(Adhesive Composition and Polarizing Plate Comprising the Same)

The present invention relates to an adhesive composition and a polarizing plate comprising the same, and more particularly, to an adhesive composition having excellent adhesion to a film having an ester group, a polarizing plate including the same, and a liquid crystal display.

The polarizing plate has a structure in which a transparent protective film is laminated on both sides or one side of a polarizer made of a polyvinyl alcohol-based resin in which dichroic dye is adsorbed and oriented.

The polarizer is produced by subjecting a polyvinyl alcohol-based resin film to longitudinal uniaxial stretching and dyeing with a dichroic dye, followed by boric acid treatment to carry out a crosslinking reaction, followed by washing with water and drying. Iodine or a dichroic organic dye is used as the dichroic dye. A polarizing plate is produced by laminating a protective film on both sides or one side of the thus prepared polarizer, and the polarizing plate thus produced is introduced into a liquid crystal display device.

A cellulose-based film is often used as the protective film, and its thickness is usually about 30 to 120 占 퐉. In addition, the protective film often uses an adhesive composed of an aqueous solution of a polyvinyl alcohol-based resin in the lamination.

However, the cellulose-based protective film has a disadvantage in that it can be bonded by an adhesive only after the step of saponifying (alkali-treating) the surface of the protective film at the time of bonding with the polarizer must be performed. UV adhesives and the like are proposed as adhesives capable of bonding the cellulose-based protective film without performing the saponification process at present. However, the UV adhesive has a lower adhesive strength than the water-based adhesive, which can induce cracking of the polarizer in the thermal shock test, and has a disadvantage in that the cost is very low due to the high price.

In addition, the cellulose-based protective film has a low moisture-and-heat resistance and thus has a disadvantage in that the performance of the polarizing plate is deteriorated or the protective film and the polarizer are peeled off. At least one protective film is composed of various resins other than cellulose- There is an attempt to do so.

However, conventional waterborne adhesives composed of an aqueous solution of a polyvinyl alcohol-based resin have a problem in that they have low adhesiveness to a film having an ester group such as an acrylic protective film (see Korean Patent Publication No. 2010-0095402).

On the other hand, in recent years, a display device which displays a stereoscopic image using polarizing glasses as one of three-dimensional image display technologies has been used. Such a display device often includes a patterned retardation film bonded to one side of the polarizer through an adhesive agent (Korean Patent Publication No. 2012-0050399).

Accordingly, there is a desperate need to develop an adhesive capable of effectively bonding a polarizer and a patterned retardation film.

Korea Patent Publication No. 2010-0095402 Korean Patent Publication No. 2012-0050399

An object of the present invention is to provide an adhesive composition excellent in adhesion to an ester group-containing film such as an acrylic protective film and a patterned retardation film.

Another object of the present invention is to provide a polarizing plate comprising an adhesive layer formed from the above adhesive composition.

It is still another object of the present invention to provide a liquid crystal display device including the polarizing plate.

On the other hand, the present invention provides an adhesive composition comprising a compound having a hydrosilylation functional group together with a primary or secondary amino group and a polyvinyl alcohol-based resin.

In one embodiment of the present invention, the hydrogen-bonding synthetic functional group includes at least one selected from the group consisting of a hydroxyl group, a carboxylic acid group and an amino group.

On the other hand, the present invention provides a polarizer comprising: a polarizer; An adhesive layer laminated on one side or both sides of the polarizer, the adhesive layer being formed from the adhesive composition; And a polarizer protective film or a patterned retardation film laminated on the adhesive layer.

On the other hand, the present invention provides a liquid crystal display device including the polarizing plate.

The adhesive composition according to the present invention not only improves the adhesive strength with an ester group-containing film such as an acrylic protective film, an unsaponifiable triacetyl cellulose protective film and a patterned retardation film which are difficult to be adhered by a conventional aqueous adhesive, And excellent heat and humidity resistance.

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

One embodiment of the present invention relates to an adhesive composition comprising a compound having a hydrosilylation functional group together with a primary or secondary amino group and a polyvinyl alcohol-based resin.

In one embodiment of the present invention, the compound having a hydrosilylation functional group together with the primary or secondary amino group reacts with an ester group present on the surface of an acrylic protective film or the like at the time of curing the adhesive composition , The hydrogen-sintering synthetic functional group can form a hydrogen bond with a hydroxyl group or the like of the polyvinyl alcohol-based resin, thereby improving the adhesion of the adhesive composition.

Examples of the hydrogen-bonding synthetic functional groups include, but are not limited to, a hydroxy group, a carboxylic acid group, an amino group, and the like.

Specific examples of the compound having a hydrosilylation functional group together with the primary or secondary amino group include a compound having a hydroxyl group and an amino group selected from compounds represented by Chemical Formulas 1 to 7, a carboxylic acid group selected from compounds represented by Chemical Formulas 8 to 13, , Compounds having a carboxylic acid group selected from the following formulas (14) to (15), a compound having a hydroxy group and an amino group, and a compound having two or more amino groups selected from the following formulas (16) to (19) Can be used at the same time.

[Chemical Formula 1]

(2)

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

(7)

[Chemical Formula 8]

[Chemical Formula 9]

[Chemical formula 10]

(11)

[Chemical Formula 12]

[Chemical Formula 13]

[Chemical Formula 14]

[Chemical Formula 15]

[Chemical Formula 16]

[Chemical Formula 17]

[Chemical Formula 18]

[Chemical Formula 19]

The compound having a hydrosilylation functional group together with the primary or secondary amino group may be contained in an amount of 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the polyvinyl alcohol-based resin, based on the solid content . If the content is less than 0.1 part by weight, the effect of improving the adhesion is insufficient. If the content is more than 10 parts by weight, peeling or bubble defects may occur under heat or moisture and heat.

In one embodiment of the present invention, the polyvinyl alcohol resin may be a modified polyvinyl alcohol resin such as acetoacetyl group denaturation, carboxyl group denaturation, methylol group denaturation, amino group denaturation, epoxy denaturation, etc., Is preferably an acetoacetyl group-modified polyvinyl alcohol-based resin.

The acetoacetyl group-modified polyvinyl alcohol resin can be obtained by reacting a polyvinyl alcohol resin with diketene by a known method. Specifically, a method of dispersing a polyvinyl alcohol-based resin in a solvent such as acetic acid and adding diketene thereto, a method of previously dissolving a polyvinyl alcohol-based resin in a solvent such as dimethylformamide or dioxane, Or a method in which a diketene gas or liquid diketene is directly contacted with a polyvinyl alcohol-based resin, or the like. The acetoacetyl group-modified polyvinyl alcohol-based resin is not particularly limited as long as the acetoacetyl group modification degree is 0.1 mol% or more, preferably 0.1 to 40 mol%, more preferably 1 to 20 mol% 2 to 7 mol%. When the degree of modification of the acetoacetyl group is less than 0.1 mol%, the water resistance of the adhesive layer is insufficient, which is unsuitable. When the degree of modification of the acetoacetyl group exceeds 40 mol%, the effect of improving the water resistance may be insignificant.

The degree of saponification of the acetoacetyl group-modified polyvinyl alcohol-based resin is not particularly limited, but is preferably 80 mol% or more, and more preferably 85 mol% or more. When the degree of saponification of the polyvinyl alcohol-based resin contained in the adhesive composition is low, sufficient water solubility is difficult to manifest, and thus the adhesiveness tends to become insufficient.

The polyvinyl alcohol used in producing the acetoacetyl group-modified polyvinyl alcohol-based resin is not particularly limited, but in order to exhibit high adhesiveness between the polarizing film and the protective film in the polarizing plate, the average degree of polymerization is in the range of 100 to 3,000 , And the average degree of saponification is preferably in the range of 80 to 100 mol%.

Examples of the products include Z-100, Z-200, Z-200H, Z-210, Z-220 and Z-320 (manufactured by Gohsefymer Japan Synthetic Chemicals).

The polyvinyl alcohol resin is preferably contained in an amount of 50 to 99 parts by weight based on 100 parts by weight of the total adhesive composition based on the solid content. When the content is less than 50 parts by weight, the adhesive strength is lowered. When the content is more than 99 parts by weight, the adhesive strength may be lowered and the water temperature resistance may be lowered.

The adhesive composition according to an embodiment of the present invention may further comprise a crosslinking agent.

The crosslinking agent serves to improve adhesion and durability of the polyvinyl alcohol-based resin, the polarizer and the polarizer protective film, reliability at high temperature, and shape of the adhesive.

The cross-linking agent may be an isocyanate-based, epoxy-based, peroxide-based, metal chelating-based, oxazoline-based, melamine-based or glyoxylate-based one or a mixture of two or more. Among them, a glyoxylate which is advantageous from the viewpoint of improvement in stickiness and durability is preferable.

The adhesive composition according to one embodiment of the present invention may further contain additives such as plasticizers, silane coupling agents, antistatic agents, fine particles, and leveling agents generally used in the art within the range not hindering the desired effect . In particular, a leveling agent or the like is preferably used to improve the spreadability of the adhesive layer forming composition.

The adhesive composition according to one embodiment of the present invention is preferably in a liquid form so as to form a uniform adhesive layer on the surface of the polarizer or the protective film as the adhesive. A solution type or dispersed liquid type of various solvents can be used for such a liquid type adhesive, and a solution type is preferable in view of the coating property of the base material, and a solution type or dispersion type in which water is used as a solvent is suitable in consideration of stability .

For the purpose of shortening the drying process, a water / alcohol mixed solvent in which an alcohol-based solvent which is easily mixed with water and has a lower boiling point than water is mixed in the adhesive solution may be used. The alcohol-based solvent preferably has a boiling point of 100 占 폚 or lower, particularly 80 占 폚 or lower, or 70 占 폚 or lower.

The use of the adhesive composition of the present invention is not limited to the bonding of the polarizer and the polarizer protective film. If the adherend is composed of components of the polarizer generally used in the art and a component of the polarizer protective film, Bonding is possible.

One embodiment of the present invention relates to a polarizer comprising: a polarizer; An adhesive layer laminated on one side or both sides of the polarizer, the adhesive layer being formed from the adhesive composition; And a polarizer protective film or a patterned retardation film laminated on the adhesive layer.

In one embodiment of the present invention, the polarizer protective film or the patterned retardation film is a film containing an ester group.

In one embodiment of the present invention, the polarizer is one in which a dichroic dye is adsorbed and oriented on a stretched polyvinyl alcohol-based film.

The polyvinyl alcohol-based resin constituting the polarizer can be obtained by saponifying a polyvinyl acetate-based resin. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Other monomers copolymerizable with vinyl acetate include acrylamide monomers having an unsaturated carboxylic acid type, an unsaturated sulfonic acid type, an olefin type, a vinyl ether type, and an ammonium group. The polyvinyl alcohol resin may also be modified. For example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The saponification degree of the polyvinyl alcohol-based resin is usually 85 to 100 mol%, preferably 98 mol% or more. The degree of polymerization of the polyvinyl alcohol-based resin is usually from 1,000 to 10,000, and preferably from 1,500 to 5,000.

Such a polyvinyl alcohol-based resin film is used as the original film of the polarizer. The method of forming the film of the polyvinyl alcohol-based resin is not particularly limited, and a known method can be used. The thickness of the original film is not particularly limited, and may be, for example, 10 to 150 mu m.

In one embodiment of the present invention, the polarizer is a film obtained by continuously uniaxially stretching a polyvinyl alcohol-based film in an aqueous solution, dyeing with a dichroic dye and adsorbing it, treating with an aqueous solution of boric acid, .

The uniaxial stretching of the polyvinyl alcohol film may be performed before dyeing, concurrently with dyeing, or may be performed after dyeing. If uniaxial stretching is carried out after dyeing, it may be carried out before the boric acid treatment, or may be carried out during the boric acid treatment. Of course, it is also possible to perform uniaxial stretching in a plurality of such steps. For uniaxial stretching, other rolls or rolls of different circumferences may be used. The uniaxial stretching may be either dry stretching in air or wet stretching in the state of being swollen with a solvent. The stretching ratio is usually 4 to 8 times.

As a step of dyeing a stretched polyvinyl alcohol film with a dichroic dye, for example, a method of immersing a polyvinyl alcohol film in an aqueous solution containing a dichroic dye can be used. As the dichroic dye, iodine or a dichroic dye is used. It is preferable that the polyvinyl alcohol film is pre-immersed in water before dyeing to swell.

When iodine is used as the dichroic dye, a method in which a polyvinyl alcohol-based film is dipped in an aqueous solution for dyeing usually containing iodine and potassium iodide may be used. Usually, the content of iodine in an aqueous solution for dyeing is 0.01 to 1 part by weight with respect to 100 parts by weight of water (distilled water), and the content of potassium iodide is 0.5 to 20 parts by weight with respect to 100 parts by weight of water. The temperature of the aqueous solution for dyeing is usually 20 to 40 占 폚, and the immersion time (dyeing time) is usually 20 to 1,800 seconds.

When a dichroic dye is used as the dichroic dye, a method of dying and dyeing the polyvinyl alcohol film is usually employed in an aqueous solution containing a water-soluble dichroic dye. The content of the dichroic dye in the aqueous solution is usually 1 × 10 ^-4 to 10 parts by weight, preferably 1 × 10 ^-3 to 1 part by weight, per 100 parts by weight of water. The aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing aid. The dye aqueous solution used for dyeing usually has a temperature of 20 to 80 캜, and the immersion time for this aqueous solution is usually 10 to 1,800 seconds.

The step of treating the dyed polyvinyl alcohol film with boric acid can be carried out by immersing it in an aqueous solution containing boric acid. Normally, the content of boric acid in an aqueous solution containing boric acid is 2 to 15 parts by weight, preferably 5 to 12 parts by weight, based on 100 parts by weight of water. When iodine is used as the dichroic dye, it is preferable that the aqueous solution containing boric acid contains potassium iodide. The content thereof is usually 0.1 to 15 parts by weight, preferably 5 to 12 parts by weight, based on 100 parts by weight of water. The temperature of the boric acid-containing aqueous solution is usually 50 ° C. or higher, preferably 50 to 85 ° C., more preferably 60 to 80 ° C. The immersing time is usually 60 to 1,200 seconds, preferably 150 to 600 seconds, 200 to 400 seconds.

After the boric acid treatment, the polyvinyl alcohol film is usually washed with water and dried. The washing treatment can be carried out by immersing the boric acid-treated polyvinyl alcohol-based film in water. The water temperature of the water treatment is usually 5 to 40 占 폚, and the immersion time is usually 1 to 120 seconds. After washing with water, the polarizer can be obtained. The drying treatment can be usually carried out using a hot air dryer or a far infrared ray heater. The drying treatment temperature is usually 30 to 100 占 폚, preferably 50 to 80 占 폚, and the drying time is usually 60 to 600 seconds, preferably 120 to 600 seconds.

The thickness of the polarizer produced as described above is typically 5 to 40 탆.

In one embodiment of the present invention, the polarizer-protective film is not particularly limited as long as it is excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, etc. Specifically, acrylic, cellulose or polyester can be used.

Acrylic resins such as polymethyl (meth) acrylate and polyethyl (meth) acrylate; Polyester resins such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate and polybutylene terephthalate; Cellulose-based resins such as diacetylcellulose and triacetylcellulose, and the like.

The thickness of the polarizer protective film is 10 to 100 탆, preferably 20 to 80 탆. Further, when the polarizer protective film is laminated on both sides of the polarizer, the same or different thickness can be maintained.

An easy joining process can be performed on the surface of the protective film to be bonded to the polarizer. Specific examples of the easy-to-bond treatment include dry treatment such as primer treatment, plasma treatment and corona treatment, chemical treatment such as alkali treatment (saponification treatment), and coating treatment for forming an easy adhesive layer.

The bonding method may be a conventional method in the art. For example, the bonding surface of the polarizer or the protective film may be formed using a flexible method, a Meyer bar coating method, a gravure coating method, a die coating method, a dip coating method, And then bonding them together. The flexographic method is a method in which the polarizer or the protective film is moved in the vertical direction, the horizontal direction, or the inclined direction between the two, while applying the adhesive composition to the joint surface. After applying the adhesive composition, a polarizer or a protective film is put on a nip roll or the like and bonded.

After bonding the polarizer and the protective film, a drying treatment can be carried out. The drying treatment is carried out, for example, by spraying hot air. The drying temperature is suitably selected in the range of 40 to 100 占 폚, preferably 60 to 100 占 폚. The drying time may be about 20 to 1,200 seconds. After drying, it is preferable to cure at a room temperature or a slightly higher temperature, for example, at a temperature of 20 to 50 DEG C for about 12 to 600 hours. The thickness of the adhesive layer after drying is usually 0.001 to 5 占 퐉, preferably 0.01 to 2 占 퐉, more preferably 0.01 to 1 占 퐉. If the thickness of the adhesive layer exceeds 5 탆, the problem of appearance defects of the polarizing plate tends to occur.

The adhesive composition of the present invention is not limited to bonding the polarizer and the polarizer protective film, and may be used for bonding the polarizer and the patterned retardation film.

The patterned retardation film is also referred to as a film patterned retarder (FPR) as a retardation layer in which a retarder pattern is repeatedly formed.

On the patterned retardation layer, one or more functional layers selected from the group consisting of an adhesive layer, an adhesive layer, a protective layer, a retardation layer, an antiglare layer, an antireflection layer, an antistatic layer and a hard coating layer may be further laminated.

The adhesive layer or the adhesive layer is for adhesion or adhesion between the functional layers. The protective layer is a layer for preventing surface cracking or damage of the polarizing plate and the patterned retardation layer. The retardation layer is a layer for further controlling the retardation. The antiglare layer is a layer formed by roughening through sand blasting, embossing, or the like, or by applying a coating liquid containing a blend of transparent fine particles to form fine irregularities on the surface. The antireflection layer is a layer composed of a metal oxide thin film formed by a vapor deposition or sputtering method to prevent external light from being reflected on the surface of the polarizing plate to inhibit the visibility of transmitted light. The antistatic layer is a layer formed by an ultraviolet curable resin containing an antistatic agent to prevent dust from adhering by static electricity. The hard coating layer serves to prevent cracks or damage from occurring on the surface of the polarizing plate, and is a layer formed by using an ultraviolet curable resin such as acrylic or silicone and serving as a cured film having excellent hardness and slipperiness.

The polarizing plate according to the present invention can be applied to all liquid crystal display devices. Therefore, one embodiment of the present invention relates to a liquid crystal display device including the polarizing plate.

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

Examples 1-9 and Comparative Examples 1-3: Preparation of adhesive composition

The components shown in Table 1 below were dissolved in distilled water in the composition shown in Table 1 below to prepare an adhesive composition having a solid content of 3% by weight.

The following composition is parts by weight based on 100 parts by weight of the polyvinyl alcohol-based resin.

Polyvinyl alcohol additive Cross-linking agent Example 1 Z100 A (2) a (5) Example 2 Z200 A (2) a (5) Example 3 Z100 B (2) a (5) Example 4 Z100 C (2) a (5) Example 5 Z100 A (2) b (5) Example 6 Z100 A (1) a (5) Example 7 Z100 A (5) a (5) Example 8 Z100 A (0.1) a (5) Example 9 Z100 A (10) a (5) Example 10 Z100 D (5) a (5) Example 11 Z100 E (5) a (5) Comparative Example 1 Z100 - a (5)

A: Compound (4)

B: Compound of formula 9

C: Compound of formula 8

D: Compound of formula 14

E: Compound of formula 16

a: glyoxylate

b: ZnCl ₂

Z100: Acetoacetyl group-modified polyvinyl alcohol resin having a degree of polymerization of 100

Z200: Acetoacetyl group-modified polyvinyl alcohol-based resin having a degree of polymerization of 200

Experimental Example 1:

(1) Peeling force measurement

The adhesive compositions of the above Examples and Comparative Examples were applied between a polarizing plate in which a triacetyl cellulose film was bonded to one surface of a polyvinyl alcohol polarizer and a polymethyl methacrylate film subjected to corona treatment and were bonded using a roll laminator . For the evaluation, the end portion was not coated with the adhesive.

Thereafter, it was dried with a hot air drier at 100 ° C for 3 minutes and allowed to stand at room temperature for 48 hours to cure.

The peeling force was measured by peeling the prepared polarizing plate sample at a rate of 300 mm / min in the 180 degree peeling direction after cutting the sample to a width of 25 cm.

(2) Evaluation of Heat Resistance and Humidity Durability

A polarizing plate was prepared by the above-mentioned method, and an acrylic pressure-sensitive adhesive was applied to the protective film and cured, and then bonded to soda glass and autoclaved.

Thereafter, each of the polymethylmethacrylate films was allowed to stand at 80 DEG C for 500 hours, at 60 DEG C and 90% RH for 500 hours, and then bubbles or peeling occurred on the bonding surface between the polymethylmethacrylate film and the polarizer. And humidity resistance.

○ : No bubbles or peeling

Δ : Bubbles or peeling were observed, but only in very small areas.

X: Bubbles or peeling can be easily confirmed with the naked eye

In the case of ○, the evaluation was made only when both the heat resistance and the heat and humidity resistance were in accordance with the above criteria. Δ and X were evaluated as Δ or X even when only one of the heat resistance and the heat and humidity resistance was in accordance with the above criteria.

Adhesion Heat resistance Humidity Durability Example 1 2.6 ○ ○ Example 2 3.1 ○ ○ Example 3 3.3 ○ ○ Example 4 2.8 ○ ○ Example 5 3.5 ○ ○ Example 6 2.4 ○ ○ Example 7 3.7 ○ ○ Example 8 1.5 △ ○ Example 9 3.9 ○ △ Example 10 3.6 ○ ○ Example 11 3.2 ○ ○ Comparative Example 1 1.1 X X

As shown in Table 2, the adhesive composition containing the compound having a hydrosilylation functional group together with the primary or secondary amino group according to the present invention has adhesiveness as well as adhesive strength as compared with the adhesive composition of Comparative Example 1, And excellent heat and humidity resistance.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Do. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Accordingly, the actual scope of the invention is defined by the appended claims and their equivalents.

Claims (10)

An adhesive composition comprising a compound having a hydrosilylation functional group together with a primary or secondary amino group and a polyvinyl alcohol-based resin. The adhesive composition according to claim 1, wherein the hydrogen-bonding synthetic functional group comprises at least one selected from the group consisting of a hydroxyl group, a carboxylic acid group and an amino group. The positive resist composition according to claim 1, wherein the compound having a hydrosilylation functional group together with the primary or secondary amino group is a compound having a hydroxyl group and an amino group, a compound having a carboxylic acid group and an amino group, a compound having a carboxylic acid group and a hydroxy group and an amino group, ≪ / RTI > wherein the adhesive comprises at least one member selected from the group consisting of compounds. The adhesive according to claim 1, wherein the compound having a hydrosilylation functional group together with the primary or secondary amino group is contained in an amount of 1 to 5 parts by weight based on 100 parts by weight of the polyvinyl alcohol resin based on the solid content Composition. The adhesive composition according to claim 1, wherein the polyvinyl alcohol-based resin is an acetoacetyl group-modified polyvinyl alcohol-based resin. The adhesive composition according to claim 1, wherein the polyvinyl alcohol-based resin is contained in an amount of 50 to 99 parts by weight based on 100 parts by weight of the total adhesive composition based on the solid content. The adhesive composition of claim 1, further comprising a crosslinking agent. A polarizer; An adhesive layer laminated on one side or both sides of the polarizer, the adhesive layer being formed from the adhesive composition; And a polarizer protective film or a patterned retardation film laminated on the adhesive layer. The polarizing plate according to claim 8, wherein the polarizer protective film or the patterned retardation film is a film containing an ester group. 9. A liquid crystal display device comprising the polarizing plate according to claim 8.