KR101919578B1 - New heterocyclic amine and adhesive composition comprising the same - Google Patents

Abstract

The present invention relates to a novel heterocyclic amine and a pressure sensitive adhesive composition containing the same. More particularly, the present invention relates to a novel heterocyclic amine having an -OH or -COOH functional group at the terminal thereof, A tertiary heterocyclic amine and a (meth) acrylate monomer having an alkyl group of 1 to 12 carbon atoms, which can significantly shorten the curing time compared to the prior art without any problem in storage stability, and is excellent in adhesion durability .

Description

TECHNICAL FIELD [0001] The present invention relates to a novel heterocyclic amine and a pressure-sensitive adhesive composition containing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a novel heterocyclic amine having a short curing time and excellent adhesion durability even under severe conditions and a pressure sensitive adhesive composition containing the same.

In general, a liquid crystal display device (LCD) includes a liquid crystal cell including a liquid crystal and a polarizing plate. In order to improve the display quality of the liquid crystal display device, various optical films (retardation plate, A brightness enhancement film or the like) is used.

A suitable pressure-sensitive adhesive is used to bond the polarizing plate and the optical film to the liquid crystal cell. The pressure-sensitive adhesive layer is previously formed on one side of the polarizing plate and the optical film so as not to perform the drying process for fixing.

As the pressure-sensitive adhesive, many acrylic pressure-sensitive adhesives based on an acrylic polymer having excellent adhesiveness and transparency are used. The crosslinking of the acrylic pressure-sensitive adhesive uses a crosslinking agent or a combination of an acrylic polymer and a functional monomer.

Since the liquid crystal display device can be installed in various environments such as high temperature and high humidity conditions, it is required to have high durability without hindering display quality even under such circumstances.

Korean Patent No. 1041765 discloses a pressure-sensitive adhesive composition using an acrylic copolymer containing acrylamide as a monomer unit. However, there is a problem that the composition does not satisfy the level of high durability.

Korean Patent Publication No. 2011-97793 discloses a pressure-sensitive adhesive composition comprising an N-vinyl cyclic monomer. However, the composition has a disadvantage of a long curing time.

The present invention is to provide a pressure-sensitive adhesive composition which is capable of shortening the curing time by increasing the crosslinking speed without any problem in storage stability, and at the same time, exhibiting excellent adhesive durability under severe conditions, using the novel heterocyclic amine.

In order to accomplish the above object, the present invention provides an acrylate-based tertiary heterocyclic amine represented by the following general formula (1).

(Wherein A is a 5- to 8-membered heterocyclic group, R ₁ is hydrogen or a methyl group, R ₂ is an alkylene group having 1 to 10 carbon atoms, and X is -OH group or -COOH group).

The present invention also provides an acrylic copolymer containing a (meth) acrylate monomer having an alkyl group of 1-12 carbon atoms and an acrylate tertiary heterocyclic amine having an -OH or -COOH functional group at a terminal.

The acrylate-based tertiary heterocyclic amine may be represented by the general formula (1).

The acrylic copolymer may have a glass transition temperature (Tg) of -50 to 0 ° C.

100 parts by weight of the (meth) acrylate monomer having an alkyl group having 1-12 carbon atoms and 0.01-10 parts by weight of an acrylate tertiary heterocyclic amine having an -OH or -COOH functional group at the terminal.

The acrylic copolymer may further contain 0.1 to 30 parts by weight of a polymerizable monomer having a crosslinkable functional group.

The acrylic copolymer may have a weight average molecular weight (polystyrene conversion, Mw) of 200,000 to 150.

The present invention also provides a pressure-sensitive adhesive composition containing the acrylic copolymer.

The pressure-sensitive adhesive composition may further contain a crosslinking agent.

The pressure-sensitive adhesive composition of the present invention increases the crosslinking speed without any problem in storage stability, so that it is easy to mass-produce since the production efficiency is excellent enough to shorten the curing time of 7 days or more to 3 days.

In addition, the pressure-sensitive adhesive composition of the present invention is excellent in adhesion durability even under severe conditions, and can be used not only as a pressure-sensitive adhesive but also as an adhesive.

The present invention relates to a novel heterocyclic amine having a short curing time and excellent adhesion durability even under severe conditions and a pressure sensitive adhesive composition containing the same.

Hereinafter, the present invention will be described in detail.

There is provided an acrylate tertiary heterocyclic amine represented by the following general formula (1).

[Chemical Formula 1]

(Wherein A is a 5- to 8-membered heterocyclic group, R ₁ is hydrogen or a methyl group, R ₂ is an alkylene group having 1 to 10 carbon atoms, and X is -OH group or -COOH group).

The acrylate-based tertiary heterocyclic amine can be produced by a method commonly used in the art. For example, the present invention is prepared using acryloyl chloride and piperidine based materials under basic conditions.

In addition, the acrylic copolymer of the present invention contains a (meth) acrylate monomer having an alkyl group having 1-12 carbon atoms and an acrylate tertiary heterocyclic amine having an -OH or -COOH functional group at a terminal.

Here, (meth) acrylate means acrylate and methacrylate.

Butyl (meth) acrylate, 2-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (Meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (Meth) acrylate, nonyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate and lauryl (meth) acrylate. Of these, n-butyl acrylate, Mixtures of these are preferred. These may be used alone or in combination of two or more.

The acrylate tertiary heterocyclic amine forms a ring structure to increase the glass transition temperature (Tg) of the acrylic copolymer, so that the durability of the adhesive containing the acrylic copolymer can be improved. Also, the tertiary amine acts as a catalyst to increase the crosslinking speed without reducing the storage stability, thereby shortening the curing time.

The acrylate tertiary heterocyclic amine is preferably represented by the following formula (1).

[Chemical Formula 1]

(Wherein A is a 5- to 8-membered heterocyclic group, R ₁ is hydrogen or a methyl group, R ₂ is an alkylene group having 1 to 10 carbon atoms, and X is -OH group or -COOH group).

Such an acrylate tertiary heterocyclic amine is preferably contained in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the (meth) acrylate monomer having an alkyl group having 1-12 carbon atoms. If the content is less than 0.01 part by weight, the effect of shortening the initial curing time and enhancing the durability is insignificant, and if it exceeds 10 parts by weight, the storage stability may be lowered.

Further, the acrylic copolymer of the present invention may further contain a polymerizable monomer having a crosslinkable functional group.

The polymerizable 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. In the present invention, in particular, the polymerizable monomer having an amide group-containing monomer (A) (B) and the hydroxy group-containing monomer (C).

Examples of the amide group-containing monomer (A) include (meth) acrylamide, N-isopropyl acrylamide and N-tertiary butyl acrylamide. These amide group-containing monomers may be used alone or in combination.

Examples of the carboxyl group-containing monomer (B) include monovalent acids such as (meth) acrylic acid, crotonic acid, and 2-carboxyethyl acrylate; 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 having 2 to 3 carbon atoms in the alkyl group, and these may be used alone or in admixture of two or more.

Examples of the hydroxyl group-containing monomer (C) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2- hydroxybutyl (meth) acrylate, , Hydroxypropyleneglycol (meth) acrylate, hydroxyalkylene glycol (meth) acrylate having 2 to 4 carbon atoms in the alkylene group, (Meth) acrylate. These may be used alone or in combination of two or more.

The weight ratio of the amide group-containing monomer (A), the carboxyl group-containing monomer (B) and the hydroxy group-containing monomer (C) is preferably 0.5-2: 0.2-1: 0.3-3. When the copolymer is contained in such a weight ratio, it has an effect of improving the durability and shortening the curing period, even though a low molecular weight copolymer is used. On the other hand, when the weight ratio of the amide group-containing monomer (A) is less than 0.5, the effect of shortening the curing period and improving the durability may be insignificant. When the weight ratio is more than 2, the storage stability is lowered and it is difficult to suppress the exfoliation of the releasing film. When the weight ratio of the carboxyl group-containing monomer (B) is less than 0.2, the effect of improving durability is insignificant, and when the weight ratio is more than 1, the peeling force may become large. If the weight ratio of the hydroxyl group-containing monomer (C) is less than 0.3, the gel fraction may be lowered and the adhesive strength may be increased. If the weight ratio is more than 3, the degree of crosslinking may increase.

The polymerizable monomer (A + B + C) thus constituted is preferably contained in an amount of 0.1 to 30 parts by weight based on 100 parts by weight of the (meth) acrylate monomer having an alkyl group having 1-12 carbon atoms. When the content is less than 0.1 part by weight, the cohesive force of the pressure-sensitive adhesive decreases, resulting in deterioration of durability or adhesion to the base film, resulting in peeling under the durability test conditions. When the content is more than 30 parts by weight, And durability may be caused, or there may be a possibility that the bonding bubble may be introduced during the initial bonding.

The acrylic copolymer may further contain other polymerizable monomers other than the above monomers in a range that does not 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 acrylic copolymer preferably has a glass transition temperature (Tg) of -50 to 0 占 폚, preferably -48 to -10 占 폚. If the glass transition temperature (Tg) is less than -50 占 폚, the durability may be deteriorated. If the glass transition temperature (Tg) is more than 0 占 폚, adhesion with the substrate may be insufficient.

The acrylic copolymer preferably has a weight average molecular weight (polystyrene reduced, Mw) of from 200,000 to 1,500,000, more preferably from 400,000 to 1,000,000, even more preferably by gel permeation chromatography (GPC) It is preferable that the number is from 500,000 to 700,000. If the weight average molecular weight is less than 200,000, cohesion between co-polymers may be insufficient, which may cause problems in adhesion durability. If the weight average molecular weight is more than 1.5 million, a large amount of a diluting solvent may be required in order to ensure fairness in coating.

The present invention may further comprise a crosslinking agent in the pressure-sensitive adhesive composition.

The crosslinking agent can improve the adhesion and durability, and can maintain the reliability at a high temperature and the shape of the pressure-sensitive adhesive.

The cross-linking agent may be an isocyanate-based, epoxy-based, peroxide-based, metal chelating-based, oxazoline-based, or the like. A double isocyanate-based is preferred.

Specifically, diisocyanate compounds such as tolylene diisocyanate, xylene diisocyanate, hexamethylene diisocyanate, 2,4- or 4,4-diphenylmethane diisocyanate, and the like; And adducts of polyhydric alcohol compounds such as trimethylolpropane of diisocyanate.

In addition to the isocyanate crosslinking agent, melamine derivatives such as hexamethylol melamine, hexamethoxymethyl melamine, hexabutoxymethyl melamine and the like; Polyepoxy compounds, for example, bisphenol A and epichlorohydrin condensate type epoxy compounds; At least one crosslinking agent selected from the group consisting of polyglycidyl ether of polyoxyalkylene polyol, glycerin di- or triglycidyl ether, and tetraglycidyl xylenediamine may be further added and used together.

Such a crosslinking agent may be contained in an amount of 0.1 to 15 parts by weight, preferably 0.3 to 5 parts by weight, based on 100 parts by weight of the acrylic copolymer. If the content is less than 0.1 part by weight, the cohesive strength may be decreased due to insufficient crosslinking, which may deteriorate the durability of the adhesive durability and the cutability. If the content is more than 15 parts by weight, the residual stress due to the excessive crosslinking reaction may be deteriorated.

The pressure-sensitive adhesive composition of the present invention may further contain a silane coupling agent.

The kind of the silane coupling agent is not particularly limited, and examples thereof include vinylchlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3- 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, Acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-acryloxypropyltrimethoxysilane , N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) Methyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3- Dimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxysilane, and the like. These may be used alone or in combination of two or more.

The silane coupling agent is preferably contained in an amount of 0 to 10 parts by weight, preferably 0.005 to 5 parts by weight, based on 100 parts by weight of the acrylic copolymer based on the solid content. If the content exceeds 10 parts by weight, the durability may be lowered.

Further, the pressure-sensitive adhesive composition of the present invention may further contain an antistatic agent.

Examples of the antistatic agent include, but are not limited to, hexylpyridinium hexafluorophosphate, dodecylpyridinium hexafluorophosphate, a fluorinated organometallic compound (for example, HQ-115 from 3M), an alkali metal salt (For example, NaPF ₆ , NaSbF ₆ , KPF ₆ and KSbF ₆ ), conductive polymers (for example, polythiophene (PEDOT of Bayer), polyaniline and polypyrrole), metal oxides (for example, indium doped tin oxide (E.g., poly (acrylamide-co-diallyldimethylammonium chloride) solution of Sigma-Aldrich), 1-butyl- 3-methylimidazolium hexafluorophosphate [BMIM] [PF ₆ ], 1-butyl-3- (2-hydroxyethyl) imidazolium bis (trifluoromethanesulfonyl) imide [BHEIM] [NTf ₂ ], tetrabutylmethylammonium bis (trifluoromethanesulfonyl) imide [TBMA] [NTf ₂ ], Etc. These may be used alone or in combination of two or more. Among them, dodecylpyridinium hexafluorophosphate, HQ-115, NaPF ₆ , 1-butyl-3- (2-hydroxyethyl) imidazolium bis (trifluoromethanesulfonyl) Imides are preferred.

The antistatic agent may be contained in an amount of 0 to 5 parts by weight, preferably 0.05 to 3 parts by weight, based on 100 parts by weight of the acrylic copolymer based on the solid content. When the content is more than 5 parts by weight, transparency may be lowered.

In addition to the above components, the pressure-sensitive adhesive composition may further contain additives such as a tackifier resin, an antioxidant, a corrosion inhibitor, a leveling agent, a surface lubricant, a dye, a pigment, and the like in order to control adhesion, cohesion, viscosity, , An antifoaming agent, a filler, a light stabilizer, and the like.

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 an 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.

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 present invention. Such variations and modifications are intended to be within the scope of the appended claims.

Synthetic example  : Acrylate series  Third Heterocyclic  Amine

Synthetic example  One

4-piperidine ethanol (100 g), triethylamine (70 g) and dichloromethane solvent (300 g) were added to a round flask (1000 mL) contained in a 0 ° C thermostat bath and then acryloyl chloride . After stirring for 2 hours, distilled water (500 mL) was added and stirred for 10 minutes. The dichloromethane layer was separated with a separating funnel and the solvent was removed by vacuum distillation to obtain N- (4-piperidineethanol) .

_{^{1 H-NMR (CDCl 3,}} ppm): 1.18 (q, 2H), 1.53 (m, 2H), 1.62 (m, 1H), 1.74 (m, 3H), 2.62 (t, 1H), 3.07 (t, (D, 1H), 3.71 (m, 2H), 3.98 (d, 1H), 4.64 (d, 1H), 5.66

Synthetic example  2

4-piperidinopropanoic acid (100 g), triethylamine (70 g) and dichloromethane solvent (300 g) were added to a round flask (1000 mL) contained in a 0 ° C thermostat bath and acryloyl chloride (100 g) Was added. After stirring for 2 hours, distilled water (500 mL) was added and stirred for 10 minutes. The dichloromethane layer was separated with a separating funnel and the solvent was removed by vacuum distillation to obtain N- (4-piperidinopropanoic acid ) Acrylamide.

_{^{1 H-NMR (CDCl 3,}} ppm): 1.18 (q, 2H), 1.54 (m, 2H), 1.63 (m, 1H), 1.73 (m, 2H), 2.35 (m, 2H), 2.61 (t, 1H), 6.25 (dd, 1H), 6.58 (m 1H), 12.15 (s, IH)

Synthetic example  3

4- (3-hydroxypropyl) piperidine (100 g), triethylamine (70 g) and a dichloromethane solvent (300 g) were added to a round flask (1000 mL) contained in a 0 ° C thermostat bath and then acryloyl chloride (100 g) was added. After stirring for 2 hours, distilled water (500 mL) was added and stirred for 10 minutes. After separating the dichloromethane layer with a separating funnel, the solvent was removed by vacuum distillation to obtain N- (4- (3-hydroxypropyl) Piperidine) acrylamide.

_{^{1 H-NMR (CDCl 3,}} ppm): 1.16 (q, 2H), 1.52 (m, 4H), 1.61 (m, 1H), 1.74 (m, 3H), 2.61 (t, 1H), 3.07 (t, 1H), 3.72 (m, 2H), 3.96 (d, IH), 4.69 (d, IH), 5.67 (dd, IH), 6.23 (dd, IH), 6.59

Synthetic example  4

4-piperidine ethanol (100 g), triethylamine (70 g) and dichloromethane solvent (300 g) were added to a round flask (1000 mL) contained in a 0 ° C thermostat bath and methacryloyl chloride Respectively. After stirring for 2 hours, distilled water (500 mL) was added and stirred for 10 minutes. The dichloromethane layer was separated with a separating funnel and the solvent was removed by vacuum distillation to obtain N- (4-piperidineethanol) Amide.

_{^{1 H-NMR (CDCl 3,}} ppm): 1.17 (q, 2H), 1.21 (s, 3H), 1.55 (m, 2H), 1.61 (m, 1H), 1.75 (m, 3H), 2.60 (t, 1H), 3.06 (t, IH), 3.74 (m, 2H), 3.99 (d, IH), 4.62 (d, IH), 5.59 (dd,

Synthetic example  5

3-pyrrolidine ethanol (100 g), triethylamine (70 g) and dichloromethane solvent (300 g) were added to a round flask (1000 mL) contained in a 0 ° C thermostat bath, and acryloyl chloride (100 g) was added . After stirring for 2 hours, distilled water (500 mL) was added and stirred for 10 minutes. The dichloromethane layer was separated with a separating funnel and the solvent was removed by vacuum distillation to obtain N- (3-pyrrolidineethanol) .

_{^{1 H-NMR (CDCl 3,}} ppm): 1.19 (q, 2H), 1.52 (m, 2H), 1.62 (m, 1H), 1.75 (m, 1H), 2.61 (t, 1H), 3.07 (t, 1H), 3.72 (m, 2H), 3.95 (d, 1H), 4.64 (d, 1H), 5.64 (dd,

Example  1 to 11 and Comparative Example  1 to 4

1) Preparation of acrylic copolymer

A monomer mixture having the composition shown in the following Table 1 was put in a 1 L reactor equipped with a cooling device for regulating the temperature of the nitrogen gas and refluxing, and 100 parts by weight of ethyl acetate (EAc) was added as a solvent. Nitrogen gas was then purged for one hour to maintain oxygen at 72 < 0 > C to remove oxygen. After the mixture was homogeneously mixed, 0.05 parts by weight of azobisisobutyronitrile (AIBN) as a reaction initiator was added and reacted for 8 hours to prepare an acrylic copolymer.

2) Preparation of pressure-sensitive adhesive composition

The acrylic copolymer prepared in 1) above was mixed in the composition shown in the following Table 1 and diluted to a concentration of 28% by weight in consideration of coating property to prepare a pressure-sensitive adhesive composition.

division
(Parts by weight) Acrylic copolymer Cross-linking agent Weight average
Molecular Weight
(just) Glass transition temperature
(° C) Acrylate
Monomer Polymerizable
Monomer Acrylate type tertiary hetero
Cyclic amine
(Synthesis Example) BA AA 2HEA One 2 3 4 5 Cor-L Cor-HXR Example 1 99 - - One - - - - 0.5 - 58 -43 Example 2 99.5 - - 0.5 - - - - 0.5 - 55 -43 Example 3 90 - - 10 - - - - 0.5 - 69 -29 Example 4 98 - One One - - - - 0.5 - 60 -40 Example 5 98.5 0.5 - One - - - - 0.5 - 61 -39 Example 6 99 - - One - - - - - 0.5 60 -43 Example 7 99 - - - One - - - 0.5 - 57 -42 Example 8 99 - - - - One - - 0.5 - 59 -43 Example 9 99 - - - - - One - 0.5 - 55 -40 Example 10 99 - - - - - - One 0.5 - 56 -41 Comparative Example 1 99 - One - - - - - 0.5 - 59 -44 Comparative Example 2 99 One - - - - - - 0.5 - 56 -40 Comparative Example 3 98.5 0.5 One - - - - - 0.5 - 58 -41 Comparative Example 4 99 - One - - - - - - 0.5 59 -44 BA: butyl acrylate
AA: Acrylic acid
2HEA: 2-hydroxyethyl acrylate
Synthesis Example 1: Synthesis of N- (4-piperidineethanol) acrylamide
Synthesis Example 2: Synthesis of N- (4-piperidine propanoic acid) acrylamide
Synthesis Example 3: Synthesis of N- (4- (3-hydroxypropyl) piperidine) acrylamide
Synthesis Example 4: Synthesis of N- (4-piperidineethanol) methacrylamide
Synthesis Example 5: Synthesis of N- (3-pyrrolidineethanol) acrylamide
Cor-L: Coronate-L (tolylene diisocyanate adduct of trimethylol propane, manufactured by Nippon Polyurethane Kogyo Co., Ltd.)
Cor-HXR: Coronate-HXR (hexamethylene diisocyanate type, manufactured by Nippon Polyurethane Kogyo Co., Ltd.)

3) Polarizer with adhesive

2) was cured on a releasing film coated with a silicone release agent to a thickness of 25 占 퐉 and dried at 100 占 폚 for 1 minute to form an adhesive layer.

The pressure-sensitive adhesive layer prepared above was laminated on an iodine-based polarizing plate having a thickness of 185 탆 by pressure-sensitive adhesive processing to produce a polarizer with a pressure-sensitive adhesive. The prepared polarizing plate was stored for a curing period under the conditions of 23 캜 and 60% RH.

Test Example

The properties of the pressure-sensitive adhesive composition and the polarizer with a pressure-sensitive adhesive prepared in the above Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 2 below.

1. Storage stability (viscosity change measurement)

The initial viscosity at the time of application of the adhesive composition thus prepared and the viscosity after being left for 24 hours were measured and the amount of change was calculated and evaluated based on the following criteria.

<Evaluation Criteria>

?: Change in viscosity <10%

×: 10% ≤ change in viscosity

2. Gel fraction

The prepared polarizer with a pressure-sensitive adhesive was cured at 23 DEG C and 65% RH for 3 days. Approximately 0.25 g of the pressure-sensitive adhesive layer of the polarizing plate with a pressure-sensitive adhesive cured on a wire mesh (125 mm x 125 mm) of a 250 mesh precisely weighed is attached, and the gel is wrapped so as not to leak. After accurately weighing the weight with a precision balance, the wire net is immersed in the ethyl acetate solution for 3 days. The immersed wire mesh is taken out, washed with a small amount of ethyl acetate solution, dried at 120 ° C for 4 hours and then weighed. Using the measured weight, the gel fraction was calculated by the following equation (1).

B is the weight of the wire netting attached to the pressure-sensitive adhesive layer (BA: weight of the pressure-sensitive adhesive, g); C is the weight of the wire netted after immersion (CA: weight of the gelled resin, g )being].

Usually, the gel fraction shows about 70 to 80% on the 7th day basis.

3. Adhesion

The prepared polarizer with a pressure-sensitive adhesive was cut into a size of 25 mm x 100 mm and the release film was peeled off. The release film was laminated to a glass substrate (# 1737, Corning) at a pressure of 0.25 MPa and autoclaved to prepare a specimen. The adhesive strength at room temperature was measured by a universal tensile tester (UTM, Instron) after allowing the specimens to stand at 23 ° C and 50% RH for 24 hours, Sensitive adhesive layer was peeled off at a peeling speed of 10 mm / min and a peeling angle of 180 deg. At this time, measurement was carried out under conditions of 23 캜 and 50% RH.

4. Durability (heat resistance / Wet heat )

The prepared polarizer with a pressure-sensitive adhesive was cut into a size of 90 mm × 170 mm, and the release film was peeled off. Then, the optical absorption axis was perpendicularly attached to both sides of the glass substrate (110 mm × 190 mm × 0.7 mm). At this time, the applied pressure was 5 kg / cm &lt; 2 &gt;, and the clean room operation was performed so that bubbles or foreign matter would not occur. The heat resistance was measured at a temperature of 80 DEG C for 1000 hours, and then the occurrence of bubbles or peeling was observed. The wet heat resistance characteristics were observed for 1000 hours under the conditions of a temperature of 60 캜 and a relative humidity of 90% RH, and then the occurrence of bubbles or peeling was observed. At this time, the sample was allowed to stand at room temperature for 24 hours immediately before evaluating the state of the specimen.

<Evaluation Criteria>

Ⓞ: No bubble or peeling

○: Bubbles or peeling <5

?: 5 pieces? Bubbles or peeling <10 pieces

X: 10 pieces &lt; bubble &

division Storage stability durability adhesiveness Gel fraction
(Third day) Heat resistance Humidity Durability Room temperature Warming Example 1 ○ ○ ◎ 2.8 10.2 78.3 Example 2 ○ ◎ ○ 3.5 12.3 70.5 Example 3 ○ ○ ○ 2.1 7.3 79.3 Example 4 ○ ◎ ○ 1.5 8.5 83.5 Example 5 ○ ◎ ◎ 2.2 9.5 79.1 Example 6 ○ ○ ○ 3.1 11.5 69.8 Example 7 ○ ○ ◎ 3.1 10.9 71.2 Example 8 ○ ○ ○ 2.5 10.1 77.8 Example 9 ○ ○ ○ 2.7 10.8 79.1 Example 10 ○ ○ ○ 2.1 11.3 75.6 Comparative Example 1 ○ × × 13.4 22.5 30.5 Comparative Example 2 ○ × × 20.3 25.8 13.8 Comparative Example 3 × × △ 8.2 20.1 47.3 Comparative Example 4 ○ × × 19.8 23.5 11.2

As shown in Table 2 above, the pressure-sensitive adhesive compositions of Examples 1 to 10 containing a specific acrylate tertiary heterocyclic amine according to the present invention had a curing time of about 3 days compared to Comparative Examples 1 to 4, Or more of the gel fraction as well as excellent durability such as heat resistance and moist heat resistance.

Claims (9)

delete An acrylic copolymer containing a (meth) acrylate monomer having an alkyl group of 1-12 carbon atoms and an acrylate tertiary heterocyclic amine represented by the following formula (1); And a polyfunctional isocyanate crosslinking agent.
[Chemical Formula 1]

(Wherein m is 0 or 1, n is 1 or 2, and R ₁ is hydrogen or a methyl group).
delete The pressure-sensitive adhesive composition according to claim 2, wherein the acrylic copolymer has a glass transition temperature (Tg) of -50 to 0 ° C.
The acrylic copolymer according to claim 2, wherein the acrylic copolymer contains 100 parts by weight of the (meth) acrylate monomer having the alkyl group having 1-12 carbon atoms and 0.01-10 parts by weight of the acrylate tertiary heterocyclic amine represented by the formula Lt; / RTI &gt;
The pressure-sensitive adhesive composition according to claim 5, wherein the acrylic copolymer further comprises 0.1 to 30 parts by weight of a polymerizable monomer having a crosslinkable functional group.
The pressure-sensitive adhesive composition according to claim 2, wherein the acrylic copolymer has a weight-average molecular weight (Mw in terms of polystyrene) of 200,000 to 1,500,000. delete delete