KR20150142450A - Pressure sensitive adhesive composition - Google Patents

Abstract

The present invention relates to an adhesive composition, a polarizing plate, and a liquid crystal display device. According to the present invention, the adhesive composition is excellent in terms of durability, optical properties, and adhesiveness. In addition, when applying the composition, while it is in an adhesive form, to an optical member, the composition exhibits anti-static performances, and can efficiently control side effects such as damage or a stain on a cell due to static electricity.

Description

[0001] PRESSURE SENSITIVE ADHESIVE COMPOSITION [0002]

The present application relates to a pressure-sensitive adhesive composition, a polarizing plate and a liquid crystal display.

2. Description of the Related Art A liquid crystal display (LCD) is an apparatus for displaying an image using liquid crystals and has advantages of low power consumption and reduced thickness in a planar view.

A polarizing plate which is an optical member used in a liquid crystal display device usually has a multilayer structure including a polyvinyl alcohol polarizer and a protective film formed on one or both sides of the polarizer. The polarizing plate generally includes a pressure-sensitive adhesive formed on one side of the protective film and capable of attaching the polarizing plate to the liquid crystal panel and a release film formed on the pressure-sensitive adhesive.

On the other hand, in order to attach the liquid crystal panel and the polarizing plate, static electricity frequently occurs in the process of peeling the release film from the polarizing plate.

Such static electricity affects the orientation of the liquid crystal inside the liquid crystal panel, causing a problem such as a malfunction.

Patent Documents 1 and 2 propose a pressure-sensitive adhesive composition comprising an ionic compound for preventing the generation of static electricity.

Patent Document 1: Korean Patent Publication No. 2013-0024847 Patent Document 2: Korea Patent Publication No. 2011-0012042

The present application provides a pressure-sensitive adhesive composition, a polarizing plate and a liquid crystal display.

The present application relates to a pressure-sensitive adhesive composition.

Exemplary pressure sensitive adhesive compositions may comprise an adhesive resin that is a polymer of a monomer mixture comprising a nitrogen containing monomer.

As used herein, the "nitrogen-containing monomer" is not particularly limited as long as it is a monomer containing nitrogen as a constituent atom, and examples thereof include dimethyl acrylamide, 2-isocyanatoethyl (meth) acrylate, (Meth) acrylate, 4-acryloylmorpholine, 1-vinyl-2-pyrrolidone, 2-isopropenyl- 2-oxazoline, N-vinylcaprolactam, and 1-vinylimidazole. Of these, dimethyl acrylamide may be preferably used.

When dimethyl acrylamide is used as the nitrogen-containing monomer, surface resistance below the desired level can be obtained even if a small amount of the ionic compound is used due to compatibility with an ionic compound described later. When applied to a polarizing plate, It is possible to suppress side effects such as cell spots and damage.

The adhesive resin of the present application is not particularly limited as long as it is a polymer of a monomer mixture containing the nitrogen-containing monomer described above. For example, an acrylic resin, a silicone resin, a rubber resin, a urethane resin, a polyester resin, .

In one example, the adhesive resin of the present application may be an acrylic resin. In addition to the nitrogen-containing monomer, the adhesive resin may further include a (meth) acrylate monomer and a crosslinkable monomer.

The kind of the (meth) acrylate monomer is not particularly limited. In the present application, for example, alkyl (meth) acrylate can be used, and specifically, from the viewpoint of controlling the cohesion, glass transition temperature and tackiness of the pressure-sensitive adhesive, the number of carbon atoms is 1 to 14, preferably 1 to 8 Alkyl (meth) acrylate having an alkyl group can be used. Examples of such monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n- (Meth) acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylhexyl (Meth) acrylate, isononyl (meth) acrylate, isononyl (meth) acrylate and the like. Among these, one kind or a mixture of two or more kinds can be used.

The crosslinkable monomer contained in the monomer mixture in the present application means a compound which simultaneously contains both a copolymerizable functional group such as a carbon-carbon double bond in the molecule and a crosslinkable functional group. The crosslinkable monomer may provide a crosslinking point by imparting a crosslinkable functional group to the acrylic resin, or may control the durability reliability, adhesive strength and cohesion of the pressure-sensitive adhesive under high temperature or high humidity conditions.

Examples of the crosslinkable monomer that can be used in the present application include a hydroxy group-containing monomer or a carboxyl group-containing monomer, which may be used alone or in combination. Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (Meth) acrylate, 2-hydroxyethyleneglycol (meth) acrylate or 2-hydroxypropyleneglycol (meth) acrylate; Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, 2- (meth) acryloyloxyacetic acid, 3- (meth) acryloyloxypropyl acid, 4- (meth) acryloyloxybutyric acid, Butyric acid, itaconic acid, maleic acid, and the like.

In the present application, the monomer mixture comprises 80 to 99.9 parts by weight of a (meth) acrylic acid ester monomer; 0.1 to 10 parts by weight of a crosslinkable monomer; And 1 to 10 parts by weight of the nitrogen-containing monomer. In the present specification, the unit " weight part " may mean a ratio of the weight between the respective components.

In another example, in the present application, the monomer mixture comprises 85 to 99 parts by weight of (meth) acrylic acid ester-based monomer; 1 to 10 parts by weight of a crosslinkable monomer; And 1 part by weight to 10 parts by weight of the nitrogen-containing monomer. By controlling the ratio of the monomers in the monomer mixture to the above range, it is possible to provide a pressure-sensitive adhesive having a surface resistance of less than a desired level, and is more effective in preventing static spots than when applied to an optical member such as a polarizing plate.

In the present application, the monomer mixture may further comprise any comonomer. Examples of such a comonomer include a compound having a copolymerizable functional group and a compound having a glass transition temperature of -130 ° C to 50 ° C in a non-crosslinked state when being polymerized with a homopolymer. In one example of the present application, the comonomer as described above may be a compound represented by the following general formula (1).

[Chemical Formula 1]

In Formula 1, R ₁ to R ₃ each independently represents hydrogen or alkyl; R ₄ represents cyano; Phenyl unsubstituted or substituted with alkyl; Acetyloxy; Or COR < _{5 &} gt ;, wherein R < ₅ > represents amino or glycidyloxy substituted or unsubstituted with alkyl or alkoxyalkyl.

In the definition of R ₁ to R _{5 in} the above formula, alkyl or alkoxy may mean straight-chain, branched-chain or cyclic alkyl or alkoxy having 1 to 12 carbon atoms, 1 to 8 carbon atoms or 1 to 4 carbon atoms, Methyl, ethyl, methoxy, ethoxy, propoxy or butoxy.

Specific examples of the compound of Formula 1 that can be used in the present application include nitrogen-containing monomers such as (meth) acrylonitrile, N-methyl (meth) acrylamide or N-butoxymethyl (meth) acrylamide; Styrene-based monomers such as styrene or methylstyrene; Glycidyl (meth) acrylate; Or a vinyl ester of a carboxylic acid such as vinyl acetate, and the like, but is not limited thereto.

The monomer mixture of the present application may contain up to 20 parts by weight of the compound of formula (1). When the proportion of the compound of the formula (1) is excessively high, there is a problem that flexibility or peel strength of the pressure-sensitive adhesive is lowered.

The method for producing the adhesive resin by polymerizing the monomer mixture in the present application is not particularly limited and includes, for example, solution polymerization, photo polymerization, bulk polymerization, suspension polymerization, Or emulsion polymerization may be used. Among them, solution polymerization is preferably used, but not limited thereto.

The pressure-sensitive adhesive composition of the present application contains an ionic compound together with the pressure-sensitive adhesive resin, which can lower the surface resistance and provide antistatic performance to the pressure-sensitive adhesive.

In one example, the ionic compound may comprise a compound comprising a nitrogen cation and a compound comprising a nitrogen anion.

The compounds containing nitrogen cations which can be used in the present application include, but are not limited to, tri-N-butylmethylammonium, N, N, N-trimethyl-N-propylammonium, N, N, N-triethylammonium, N, N-dimethyl-N-propylammonium, 1-methyl-N, N, N-trioctylammonium, N-ethyl-N, N, N-trihexylammonium, N-methyl- But are not limited to, tri- N-butylmethylammonium, N, N, N-trimethyl-N-propylammonium and 1-ethyl-3-methylimidazolium May be at least one selected from the group consisting of

The compound containing a nitrogen anion usable in the present application is not particularly limited as long as it has a perfluoroalkyl group.

The perfluoroalkyl group may be, for example, a perfluoroalkyl group having 1 to 20 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms or 1 to 4 carbon atoms, in which case a linear, branched or cyclic structure But it is preferable to have a linear or branched structure.

The nitrogen-containing compound includes, for example, tris trifluoromethanesulfonylmethide, bistrifluoromethanesulfonylimide, bisperfluorobutanesulfonylimide, bispentafluoroethanesulfonylimide , Tris trifluoromethanecarbonylmide, bis perfluorobutanecarbonylimide, and bis pentafluoroethanecarbonylimide, and preferably at least one selected from the group consisting of bistrifluoro Methanesulfonylimide can be used.

Specific examples of the ionic compound of the present application include tri-N-butylmethylammonium bistrifluoromethanesulfonylimide, N, N, N-trimethyl-N-propylammonium bistrifluoromethanesulfonylimide, 1 Methyl-N, N, N-tributylammonium bistrifluoromethanesulfonylimide, N-methyl-N, N, N-tributylammonium bis pentafluoroethanesulfonylimide, N-ethyl-N, N, N-trioctylammonium bistrifluoromethanesulfonylimide, N-ethyl-N, N, Ammonium bispentafluoroethanesulfonylimide, N-ethyl-N, N, N-tributylammonium bistrifluoromethanesulfonylimide and N-ethyl-N, N, N-tributylammonium bis pentafluoro Butanetetramine, and roethanesulfonylimide, but is not limited thereto, preferably tri-N-butylmethylammonium bist N, N, N-trimethyl-N-propylammonium bistrifluoromethanesulfonylimide and 1-ethyl-3-methylimidazolium bistrifluoromethanesulfonylimide May be at least one selected from the group consisting of

In the pressure-sensitive adhesive composition of the present application, the ionic compound may be contained in an amount of 1 to 10 parts by weight, 1 to 7.5 parts by weight, or 1 to 5 parts by weight based on 100 parts by weight of the adhesive resin. By adjusting the content of the ionic compound to the above range, the properties such as durability and reliability can be maintained at the same time even under high temperature or high temperature / high humidity including antistatic performance of the pressure sensitive adhesive.

In the present application, the nitrogen-containing monomer contained in the pressure-sensitive adhesive composition is included in the pressure-sensitive adhesive resin and the ratio of the ionic compound is suitably adjusted to effectively control the antistatic property, for example, the surface resistance value. For example, in the present application, the pressure-sensitive adhesive prepared by curing the pressure-sensitive adhesive composition may satisfy the following general formula (1).

[Formula 1]

X? 10 10 ¹⁰ ? /?

In the general formula (1), X represents the surface resistance of the pressure-sensitive adhesive measured after allowing the pressure-sensitive adhesive, which is a cured product of the pressure-sensitive adhesive composition of the present application, to stand at room temperature for 16 hours. As used herein, the term " ambient temperature " refers to a natural temperature that is not warmed or warmed, for example, a temperature of about 15 캜 to 35 캜, about 20 캜 to 25 캜, about 25 캜, It can mean.

In another embodiment, the pressure-sensitive adhesive prepared by curing the pressure-sensitive adhesive composition may have a surface resistance value of 9 10 ¹⁰ ? / ?, 8 10 ¹⁰ ? / Or 7 10 ¹⁰ ? / ?. By adjusting the surface resistance of the pressure-sensitive adhesive within the above-mentioned range, it is possible to suppress side effects such as stain or damage due to static electricity.

The pressure-sensitive adhesive composition may further comprise a multifunctional crosslinking agent capable of crosslinking the pressure-sensitive adhesive resin. The multifunctional crosslinking agent includes at least two or more functional groups capable of reacting with the crosslinkable functional group contained in the pressure-sensitive adhesive resin, 2 to 10, 2 to 8, 2 to 6, or 2 to 4 May be used.

As such a cross-linking agent, an appropriate type may be selected and used from among conventional cross-linking agents such as an isocyanate cross-linking agent, an epoxy cross-linking agent, an aziridine cross-linking agent or a metal chelate cross-linking agent considering the kind of the cross-linkable functional group of the adhesive polymer.

Examples of the isocyanate crosslinking agent include diisocyanate compounds such as tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylene diisocyanate, and naphthalene diisocyanate; And a reaction product of a polyol such as trimethylolpropane or an isocyanurate adduct of the above diisocyanate compound. Of these, xylene diisocyanate or hexamethylene diisocyanate can be preferably used. As the epoxy crosslinking agent Is preferably at least one selected from the group consisting of ethylene glycol diglycidyl ether, triglycidyl ether, trimethylolpropane triglycidyl ether, N, N, N ', N'- tetraglycidylethylenediamine and glycerin diglycidyl ether There is at least one selected from the group true can be exemplified.

As the aziridine crosslinking agent, N, N'-toluene-2,4-bis (1-aziridinecarboxamide), N, N'-diphenylmethane-4,4'- (2-methyl aziridine) or tri-1-aziridinyl phosphine oxide, and the like, but not limited thereto, and the metal chelate Examples of the crosslinking agent include compounds in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, and / or vanadium is coordinated to acetylacetone or ethyl acetoacetate.

The multifunctional crosslinking agent may be contained in an amount of, for example, 0.001 to 10 parts by weight, 0.005 to 5 parts by weight or 0.01 to 1 part by weight based on 100 parts by weight of the adhesive resin. It is possible to provide an adhesive excellent in endurance reliability by controlling the polyfunctional crosslinking agent to be included in the adhesive resin in the above-mentioned range to induce an effective crosslinking reaction.

The pressure-sensitive adhesive composition of the present application may further include a silane-based coupling agent. The above coupling agent can improve adhesion, adhesion stability, heat resistance and moisture resistance of an adherend, in particular, a glass substrate and a pressure-sensitive adhesive, and improve adhesive reliability when the pressure-sensitive adhesive is left for a long time under high temperature or high humidity conditions. The type of the silane coupling agent usable in the present application is not particularly limited and includes, for example,? -Glycidoxypropyltrimethoxysilane,? -Glycidoxypropylmethyldiethoxysilane,? -Glycidoxypropyl tri Vinyltrimethoxysilane, vinyltriethoxysilane,? -Methacryloxypropyltrimethoxysilane,? -Methacryloxypropyltriethoxysilane,? -Methacryloxypropyltrimethoxysilane,? -Methacryloxypropyltrimethoxysilane,? -Methacryloxypropyltrimethoxysilane, Aminopropyltrimethoxysilane,? -Aminopropyltriethoxysilane, 3-isocyanatepropyltriethoxysilane, and the like, or a mixture of two or more of them may be used.

In the pressure-sensitive adhesive composition of the present application, the silane-based coupling agent may be included in an amount of 0.005 part by weight to 5 parts by weight based on 100 parts by weight of the adhesive resin. By controlling the content ratio of the coupling agent as described above, it is possible to secure an effective adhesive force increasing effect and maintain the durability reliability of the pressure-sensitive adhesive excellent.

The pressure-sensitive adhesive composition of the present application may further comprise a tackifier resin. The kind of the tackifier resin that can be used in the present invention is not particularly limited, and is usually used in the pressure sensitive adhesive production field, for example, a hydrocarbon resin or a hydrogenated product thereof; Rosin resin or hydrogenated product thereof; Rosin ester resins or hydrogenated products thereof; Terpene resin or hydrogenated product thereof; Terpene phenol resin or hydrogenated product thereof; A polymerized rosin resin, a polymerized rosin ester resin and the like, or a mixture of two or more thereof.

In the present application, the tackifier resin may be contained in an amount of 1 part by weight to 100 parts by weight based on 100 parts by weight of the adhesive resin, but the content ratio may be appropriately changed according to the purpose.

The pressure-sensitive adhesive composition of the present application may also contain one or more additives selected from the group consisting of epoxy resins, crosslinking agents, ultraviolet stabilizers, antioxidants, colorants, reinforcing agents, fillers, defoamers, surfactants and plasticizers, May be further included.

The present application also relates to a polarizer comprising: a polarizer; And a pressure-sensitive adhesive layer formed on one side or both sides of the polarizer and including a cured product of the pressure-sensitive adhesive composition.

The type of the polarizer included in the polarizing plate of the present application is not particularly limited. For example, as the polarizer, a polarizing component such as iodine or dichroic dye is contained in a polyvinyl alcohol-based resin film, Can be used. As the polyvinyl alcohol-based resin, a hydrolyzed product of polyvinyl alcohol, polyvinyl formal, polyvinyl acetal or ethylene-vinyl acetate copolymer can be used.

In the present application, the thickness of the polarizer is not particularly limited, and it may be formed in a usual thickness.

The polarizing plate of the present application may further have a transparent protective film adhered to one side or both sides of the polarizer, and in some cases, the pressure sensitive adhesive may be laminated on one side of the transparent protective film. The type of protective film that can be included in the polarizing plate is not particularly limited, and examples thereof include cellulose-based films such as triacetyl cellulose; Polyester films such as a polyethylene terephthalate film; Polycarbonate-based films; Acrylic film; Polyethersulfone-based films; Or a conventional film such as a polyethylene film, a polypropylene film, a cyclo-based polyolefin film, a norbornene-based polyolefin film, or a polyolefin-based film such as an ethylene-propylene copolymer.

In the present application, the thickness of the protective film is not particularly limited, and can be formed to a conventional thickness.

The method for forming the pressure-sensitive adhesive on the polarizer or the transparent protective film is not particularly limited. For example, the polarizer or the transparent protective film may be coated with a pressure-sensitive adhesive composition or a coating liquid containing the same by a general means such as a bar coater or a comma coater, followed by curing by heating, drying and / or aging, A method in which a pressure-sensitive adhesive is formed on the surface of a substrate in the same manner as described above, and then the pressure-sensitive adhesive is transferred.

In the present application, from the viewpoint of uniform coating performance, it is preferable that the crosslinking reaction of the functional group of the polyfunctional crosslinking agent contained in the composition or the coating liquid is controlled not to proceed during the formation of the pressure-sensitive adhesive. That is, the multifunctional crosslinking agent forms a crosslinked structure during the drying or aging process after coating to improve the cohesive force, thereby improving the adhesive property and cuttability of the pressure-sensitive adhesive. Further, in the present application, it is preferable to remove the bubble-inducing component such as volatile components or reaction residues in the composition or coating liquid sufficiently before forming the pressure-sensitive adhesive. If the crosslinking density or molecular weight is too low to lower the elastic modulus, small bubbles existing between the pressure-sensitive adhesive and the adherend become large at a high temperature, thereby forming a scattering body inside.

The method of curing the pressure-sensitive adhesive composition of the present application in the production of the polarizing plate is also not particularly limited, and general photocuring or thermosetting methods in this field may be applied.

In the present application, the surface resistance of the above-mentioned pressure-sensitive adhesive may be ¹⁰ 10 ¹⁰ ? /? Or less as described above, and this value can be stably maintained for a long period of time.

In the polarizing plate of the present application, the pressure sensitive adhesive may also have a gel content of 5% to 99% represented by the following general formula (2).

[Formula 2]

Gel content (%) = B / A x 100

In the general formula 2, A represents the mass of the pressure-sensitive adhesive layer, and B represents the dry mass of the insoluble fractions collected after 48 hours of immersion in the pressure-sensitive adhesive layer at room temperature in ethyl acetate.

In the above, the dry weight of the insoluble powder was measured by immersing the pressure-sensitive adhesive in ethyl acetate at room temperature for 48 hours, collecting insoluble fractions, drying and removing ethyl acetate contained in the insoluble fractions collected under appropriate conditions and then measuring .

In the present application, it is possible to provide a pressure sensitive adhesive having an appropriate cohesive force and excellent durability reliability by adjusting the gel content to the above range.

The polarizing plate of the present application may further include at least one functional layer selected from the group consisting of a protective layer, a reflective layer, an antiglare layer, a retardation film, a wide viewing angle compensation film, and a brightness enhancement film.

The present application also relates to a liquid crystal display device including a liquid crystal panel in which the above-mentioned polarizing plate is bonded to one or both surfaces.

The pressure-sensitive adhesive of the present application can be freely applied to various kinds of liquid crystal panels because the desired surface resistance value can be freely implemented and the surface resistance value does not change with time.

In one example, the liquid crystal display device includes a liquid crystal panel including a liquid crystal layer interposed between upper and lower transparent substrates; An ITO thin film formed on the upper surface of the upper transparent substrate; And a polarizer attached to the ITO thin film on the upper transparent substrate or the lower transparent substrate via a pressure-sensitive adhesive formed from a cured product of the pressure-sensitive adhesive composition of the present invention having a surface resistance of 10 10 ¹⁰ ? /? Or less.

The term " polarizing plate directly attached to the upper transparent substrate " in the above refers to a polarizing plate attached directly to the upper transparent substrate on which the ITO thin film not formed, which is ordinarily formed for the purpose of preventing electrification, And a polarizer is attached to the polarizer through the polarizer.

Since the pressure-sensitive adhesive of the present application can effectively control the surface resistance value, and the surface resistivity value thus regulated can be stably maintained for a long period of time under normal or harsh conditions, the ITO thin film formed in the past can be partially formed It is possible to prevent problems such as malfunction of the device caused by static electricity or the like, even if it is not formed.

The type of the liquid crystal panel constituting the liquid crystal display device of the present application is not particularly limited and may be selected from the group consisting of TN (Twisted Neumatic), STN (Super Twisted Neumatic), IPS (In Plane Switching) It includes all common liquid crystal panels. Further, the other types of constitution and other manufacturing methods of the liquid crystal display device of the present application are not particularly limited, and general configurations in this field can be employed without any limitations.

The pressure sensitive adhesive of the present application can also be applied to various fields requiring optical transparency, durability reliability and antistatic performance in addition to the above liquid crystal display device. For example, a reflective sheet, a structural adhesive sheet, a photographic adhesive sheet, , Optical adhesive products, pressure sensitive adhesives for electronic components, protective films, and the like. In addition, the pressure-sensitive adhesive composition of the present application can be applied to a multilayered laminate product such as a general commercial pressure-sensitive adhesive sheet product, a medical patch, or heat activated pressure sensitive adhesives.

The pressure-sensitive adhesive composition of the present application is excellent in durability, optical properties and tackiness, and can effectively suppress side effects such as antistatic performance and stain or damage due to static electricity when applied to an optical member in the form of a pressure-sensitive adhesive.

Hereinafter, the present application will be described in more detail by way of examples according to the present application and comparative examples that do not comply with the present application, but the scope of the present application is not limited by the following examples and comparative examples.

1. Evaluation of molecular weight

The weight average molecular weight (Mn) and the molecular weight distribution (PDI) were measured using GPC under the following conditions, and the measurement results were converted using a standard polystyrene of Agilent system for the calibration curve.

<Measurement Conditions>

Measuring instrument: Agilent GPC (Agilent 1200 series, U.S.)

Column: Two PL Mixed B connections

Column temperature: 40 ° C

Eluent: THF (Tetrahydrofuran)

Flow rate: 1.0 mL / min

Concentration: ~ 1 mg / mL (100 μL injection)

2. Evaluation of durability

The polarizing plates prepared in Examples and Comparative Examples were cut to a width of about 300 mm and a length of about 400 mm to prepare specimens, which were then attached to glass. Thereafter, the durability of the sample was evaluated by observing occurrence of lifting, bubbling and peeling at the adhesive interface after the sample was left for 240 hours at 60 ° C and 90% relative humidity, and evaluated according to the following criteria.

<Evaluation Criteria>

A: No lift, no bubbles and peeling

B: Extension, bubble and / or slight peeling occurred

C: Large amount of lifting, bubbling and / or peeling occurred

3. Evaluation of surface resistance

The polarizing plate was maintained at 25 DEG C and 50% RH (room temperature condition); 80 캜 (heat-resistant condition); And 60 ° C and 90% RH (wet heat-resistant condition), respectively, for 1,000 hours, and then the surface resistance was measured in each case. The specimens were allowed to stand at room temperature for 24 hours immediately before the evaluation. The surface resistance was measured by removing the release film from the polarizing plate and measuring the surface resistance of the adhesive surface. Specifically, after applying a voltage of 500 V for 10 seconds under the environment of 23 ° C and 50% RH, Respectively.

Manufacturing example  1. Production of pressure-sensitive adhesive resin (A1)

91 parts by weight of n-butyl acrylate (BA), 3 parts by weight of dimethylacrylamide (DMAA) and 6 parts by weight of acrylic acid (AA) were added to a 1 L reactor equipped with a cooling device to easily regulate the temperature, Respectively. Subsequently, 100 parts by weight of ethyl acetate (EAc) was added with a solvent. Nitrogen gas was purged for oxygen removal for 60 minutes. While maintaining the temperature at 60 占 폚, azobisisobutyronitrile AIBN) was added thereto to initiate the reaction. The reaction product was reacted for about 8 hours and diluted with ethyl acetate (EAc) to prepare a pressure-sensitive adhesive resin (A1).

Manufacturing example  2 to Manufacturing example  5. Preparation of Adhesive Resins (A2 to A4 and B1)

Adhesive resins (A2 to A4 and B1) were prepared in the same manner as in Production Example 1, except that raw materials and additives used in polymerization of adhesive resin (A1) in Production Example 1 were controlled as shown in Table 1 below. .

Raw material EA V-65 BA DMMA AA NVC point
Cling
Number
G A1 91 3 6 - 100 0.04 A2 89 5 6 - 100 0.04 A3 87 7 6 - 100 0.04 A4 91 - 6 3 100 0.04 B1 94 - 6 - 100 0.04 Content Unit: g
BA: n-butyl acrylate
DMMA: dimethyl acryl amide
AA: acrylic acid
NVC: n-vinyl carprolactam
EA: ethyl acetate
V-65: 2,2'-azobis (2,4-dimethyl valeronitrile)

Example  One

Preparation of pressure-sensitive adhesive composition

0.02 part by weight of a crosslinking agent (4-functional group epoxy curing agent, BXX-5240, Toyo ink) and 0.02 part by weight of an ionic compound tri-n-butylmethylammonium bis- (trifluoro (2-ethylhexyl) imide) (FC4400, 3M) were mixed and ethyl acetate was mixed as a solvent to prepare a pressure-sensitive adhesive composition.

Production of Polarizer

The pressure-sensitive adhesive composition thus prepared was coated on a release paper and dried and aged under appropriate conditions to prepare a pressure-sensitive adhesive having a thickness of 25 탆. Then, the produced pressure-sensitive adhesive was laminated on a VA mode polarizing plate having a thickness of 125 탆 to prepare a polarizing plate.

Example  2 to 4 and Comparative Example  One

A pressure-sensitive adhesive composition and a polarizing plate were prepared in the same manner as in Example 1, except that components and ratios were adjusted as shown in Table 2 below.

Example Comparative Example One 2 3 4 One cohesion
Suzy Kinds A1 A2 A3 A4 B1 content 100 100 100 100 100 Crosslinker content 0.02 0.02 0.02 0.02 0.02 Ionic compound content 2 2 2 2 2 Content Unit: parts by weight
Crosslinking agent: BXX-5240, Toyo ink
Ionic compound: tri-n-buthylmethylammonium bis- (trifluoromethanesulfonyl) imide) (FC4400, 3M Company)

The results of the physical properties evaluation of each of the above Examples and Comparative Examples are shown in Table 3 below.

Example Comparative Example One 2 3 4 One Molecular weight (unit: million) 160 155 150 180 180 PDI 4.0 4.0 4.0 4.0 4.5 durability A A A A A Surface resistance
(Unit: 10 ¹⁰ Ω / □) 6.5 6.2 5.8 6.4 17

Claims (15)

An adhesive resin which is a polymer of a monomer mixture comprising a nitrogen-containing monomer; And
A compound containing a nitrogen cation and an ion compound of a compound containing a nitrogen anion,
A pressure-sensitive adhesive composition which satisfies the following general formula (1):
[Formula 1]
X? 10 10 ¹⁰ ? /?
In the general formula (1), X represents the surface resistance of the pressure-sensitive adhesive measured after allowing the pressure-sensitive adhesive, which is a cured product of the pressure-sensitive adhesive composition, to stand at room temperature for 168 hours. The method of claim 1, wherein the nitrogen-containing monomer is selected from the group consisting of dimethyl acrylamide, 2-isocyanatoethyl (meth) acrylate, 3-isocyanatopropyl (meth) acrylate, 4-isocyanatobutyl Acrylate, 1-vinyl-2-pyrrolidone, 2-isopropenyl-2-oxazoline, N-vinylcaprolactam, and 1-vinylimidazole Wherein the pressure-sensitive adhesive composition is at least one selected from the group consisting of The pressure-sensitive adhesive composition according to claim 1, wherein the nitrogen-containing monomer is dimethyl acrylamide. The pressure-sensitive adhesive composition according to claim 1, wherein the monomer mixture further comprises a (meth) acrylic acid ester-based monomer and a crosslinkable monomer. 5. The composition according to claim 4, wherein the monomer mixture comprises 80 to 99.9 parts by weight of a (meth) acrylic acid ester monomer;
0.1 to 10 parts by weight of a crosslinkable monomer; And
1 to 10 parts by weight of a nitrogen-containing monomer. 2. The process of claim 1, wherein the compound comprising nitrogen cations is selected from the group consisting of tri-N-butylmethylammonium, N, N, N-trimethyl-N-propylammonium, , N-dimethyl-N-propylammonium, N-methyl-N, N, N-tributylammonium, N-ethyl-N, N, N-tributylammonium, Ammonium, N, N, N, N-trioctylammonium, N-methyl-N, N, N-trioctylammonium, Or more. 2. The process of claim 1, wherein the compound comprising nitrogen cations is selected from the group consisting of tri-N-butylmethylammonium, N, N, N-trimethyl-N-propylammonium and 1-ethyl- Or more. The composition of claim 1, wherein the compound comprising a nitrogen anion is selected from the group consisting of tris trifluoromethanesulfonylmethide, bistrifluoromethanesulfonylimide, bisperfluorobutanesulfonylimide, bispentafluoroethanesulfonyl At least one selected from the group consisting of bis (trifluoromethanesulfonyl) imide, bis (trifluoromethanesulfonyl) imide, bis (perfluorobutane) carbonylimide and bis (pentafluoroethanecarbonyl) imide. The pressure-sensitive adhesive composition according to claim 1, wherein the compound containing a nitrogen anion is bistrifluoromethanesulfonylimide. The process of claim 1 wherein the ionic compound is selected from the group consisting of tri-N-butylmethylammonium bistrifluoromethanesulfonylimide, N, N, N-trimethyl-N-propylammonium bistrifluoromethanesulfonylimide, 1- Ethyl-3-methylimidazolium bistrifluoromethanesulfonylimide, N-methyl-N, N, N-tributylammonium bistrifluoromethanesulfonylimide, N-methyl-N, N, N N-ethyl-N, N, N-trioctylammonium bistrifluoromethanesulfonylimide, N-ethyl-N, N, N-trioctylammonium Bis-pentafluoroethanesulfonylimide, N-ethyl-N, N, N-tributylammonium bistrifluoromethanesulfonylimide, and N-ethyl-N, N, N-tributylammonium bis pentafluoro Ethanesulfonylimide, and mixtures thereof. 2. The process of claim 1 wherein the ionic compound is selected from the group consisting of tri-N-butylmethylammonium bistrifluoromethanesulfonylimide, N, N, N-trimethyl-N-propylammonium bistrifluoromethanesulfonylimide and 1- Ethyl-3-methylimidazolium bistrifluoromethanesulfonylimide, and mixtures thereof. The pressure-sensitive adhesive composition according to claim 1, wherein the ionic compound is contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the pressure-sensitive adhesive resin. The pressure-sensitive adhesive composition according to claim 1, further comprising 0.001 to 5 parts by weight of a multifunctional crosslinking agent based on 100 parts by weight of the pressure-sensitive adhesive resin. A polarizer; And
And a pressure-sensitive adhesive layer formed on one side or both sides of the polarizer and including a cured product of the pressure-sensitive adhesive composition according to claim 1. Wherein the polarizer according to claim 14 is adhered to one surface or both surfaces of the liquid crystal panel.