JP2009512753A - Adhesive composition - Google Patents

Abstract

The present invention relates to a pressure-sensitive adhesive composition, and more precisely, a pressure-sensitive adhesive composition containing an organic silane compound that exhibits excellent initial adhesive strength on a substrate, and does not leave any of the adhesive behind when removed because the adhesive power is not excessively increased even at high temperature or at high temperature and high humidity.

Description

  The present invention relates to a pressure-sensitive adhesive composition. More specifically, the present invention is excellent in initial adhesive force when adhering to a substrate, and does not excessively increase adhesive force at high temperature or high temperature and high humidity, and is re-peeled. The present invention relates to a pressure-sensitive adhesive composition that sometimes does not leave a pressure-sensitive adhesive on a substrate.

  In general, in order to manufacture a liquid crystal display device, a liquid crystal cell containing liquid crystal and a polarizing plate are basically required, and an appropriate adhesive layer or adhesive layer for bonding the liquid crystal cell is necessary. In order to improve the function of the liquid crystal display device, a retardation plate, a wide viewing angle compensation plate, a brightness enhancement film, or the like can be additionally attached to the polarizing plate.

  The main structure forming the liquid crystal display device is a liquid crystal layer arranged in a uniform manner; an adhesive layer or an adhesive layer based on a liquid crystal cell composed of a transparent glass plate or a plastic plate material including a transparent electrode layer In general, it includes a polarizing plate having a multilayer structure united by the above; a retardation plate; and an additional functional film layer.

  As a pressure-sensitive adhesive used for bonding the polarizing plate, Japanese Patent Publication No. 3022993 discloses an acrylic pressure-sensitive adhesive composition containing a silane compound having an epoxy group. Discloses a pressure-sensitive adhesive composition containing a silane compound having a hydrocarbon group. However, when using a pressure-sensitive adhesive containing a silane compound as described above, it is difficult to maintain an appropriate adhesive strength as required in an environment where the substrate and the polarizing plate are actually used, or high temperature / high humidity. Adhesive strength rises excessively under certain conditions, and there may be a problem that the pressure-sensitive adhesive remains on the substrate during re-peeling.

Japanese Patent Application Laid-Open No. 8-104855 not only allows a polarizing plate to be adhered to the surface of the substrate with good adhesive strength, but also allows the substrate to be damaged without leaving any adhesive or leaving an adhesive. In order to peel the polarizing plate from the surface, an adhesive composition in which a silane compound having a β-ketoester group and an alkoxy group is contained in an acrylic polymer is disclosed.
Japanese Patent No. 3022993 Specification JP 7-331204 A JP-A-8-104855

  In order to solve the problems of the prior art as described above, the present invention can be used for the purpose of improving the adhesion between a resin layer made of a matrix resin and a substrate, and in particular, a liquid crystal display device. Adhesion to glass substrates improves adhesion to glass substrates and contains a new organosilane compound that has little change over time even under high temperature and high humidity. It is an object of the present invention to provide a pressure-sensitive adhesive composition that is excellent in adhesion, does not excessively increase adhesive strength at high temperature or high temperature and high humidity, and does not leave the pressure-sensitive adhesive on the substrate at the time of re-peeling.

  Another object of the present invention is to provide a polarizing plate and a liquid crystal display device to which the pressure-sensitive adhesive composition having the above properties is applied.

  In order to achieve the above object, the present invention provides a pressure-sensitive adhesive resin composition comprising an organosilane compound represented by the following chemical formula 1.

(In the above formula, R ₁ , R ₂ , and R ₃ are each independently hydrogen or an alkyl group having 1 to 3 carbon atoms, and X is —NR ₄ — (where R ₄ is hydrogen or A C 1-3 alkyl group), an oxygen atom, or a sulfur atom, n is an integer of 3-10, and j is an integer of 1-3.

Specifically, the present invention
a) i) 90 to 99.9% by weight of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and ii) a vinyl monomer and / or acrylic having a crosslinkable functional group 100 parts by weight of an acrylic copolymer obtained by copolymerizing 0.1 to 10% by weight of a monomer.
b) 0.01 to 10 parts by weight of a polyfunctional crosslinking agent; and c) 0.01 to 5 parts by weight of the organosilane compound represented by Chemical Formula 1.

  Moreover, this invention provides the polarizing plate characterized by including the said adhesive composition as an adhesive layer in the one or both surfaces of a polarizing film.

  The present invention also provides a liquid crystal display device including a liquid crystal panel in which the polarizing plate is bonded to one or both surfaces of a liquid crystal cell.

  Hereinafter, the present invention will be described in detail.

  As a result of applying the organic silane compound represented by the above chemical formula 1 to the pressure-sensitive adhesive composition, the present inventors have conducted extensive research to obtain a high-functional pressure-sensitive adhesive used in the production of liquid crystal display devices. It is excellent in initial adhesive strength when attached to the substrate, and it is confirmed that the adhesive strength does not increase excessively at high temperature or under high temperature and high humidity, and that the adhesive does not remain on the substrate at the time of re-peeling, and the present invention is completed. It came to.

  The pressure-sensitive adhesive composition of the present invention comprises an organosilane compound represented by the above chemical formula 1.

  The organosilane compound represented by the above chemical formula 1 can also be produced by reacting 1-alkenyl cyanoacetate and trialkoxysilane in the presence of a chloroplatinic acid catalyst, and cyanoacetyl chloride and N in the presence of a tertiary amine. It can also be produced by reacting with -alkylaminoalkyltrialkoxy.

  In addition, the above reaction is carried out in an alkyl halide solvent such as chloroform, methylene chloride, dichloroethane, etc .; a cyclic ether solvent such as tetrahydrofuran, dioxin, etc .; or an aromatic organic solvent such as benzene, toluene, xylene, etc. Can progress.

  The temperature during the reaction is preferably from 10 to 200 ° C., more preferably from 50 to 150 ° C. During the reaction, vacuum distillation can also be performed for purification.

Of the organosilane compounds represented by the above chemical formula 1 of the present invention produced through the above reaction, R ₁ is particularly preferably a phenyl group.

  In addition, the silane compound represented by Chemical Formula 1 of the present invention as described above is specifically cyanoacetoxypropyltrimethoxysilane represented by the following Chemical Formula 2, N-methyl-N— ( 3-trimethoxysilylpropyl) cyanoacetamide and the like.

  The pressure-sensitive adhesive composition of the present invention containing the organosilane compound represented by the chemical formula 1 as described above specifically includes: a) i) a (meth) acrylic acid ester having an alkyl group having 1 to 12 carbon atoms Acrylic copolymer 100 obtained by copolymerizing 90 to 99.9% by weight of a polymer and ii) 0.1 to 10% by weight of a vinyl monomer having a crosslinkable functional group and / or an acrylic monomer. Parts by weight; b) 0.01 to 10 parts by weight of a polyfunctional crosslinking agent; and c) 0.01 to 5 parts by weight of the organosilane compound represented by Formula 1.

  The acrylic copolymer of a) used in the present invention comprises: i) 90 to 99.9% by weight of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms; A copolymer obtained by copolymerizing a vinyl monomer having a functional group and / or 0.1 to 10% by weight of an acrylic monomer can be used.

  As the (a) i) (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, an alkyl ester having 1 to 12 carbon atoms of acrylic acid (or methacrylic acid) can be used. Preferably, an alkyl ester having 2 to 8 carbon atoms is used. That is, in the alkyl (meth) acrylate, when the alkyl group becomes a long chain, the cohesive force of the pressure-sensitive adhesive is reduced. Therefore, in order to maintain the cohesive force at a high temperature, the alkyl group has 1 to 12 carbon atoms. Preferably, the alkyl group is selected in the range of 2 to 8 carbon atoms.

  Specifically, the (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms is butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) Acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, n-octyl methacrylate, isooctyl (meth) acrylate, and isononyl (meth) acrylate It can be used alone or in combination of two or more.

  In addition, a copolymerizable monomer can be further used to adjust the glass transition temperature of the pressure-sensitive adhesive or to impart other functional characteristics during the production of the acrylic copolymer. In particular, acrylonitrile, styrene, glycidyl (meth) acrylate, vinyl acetate, or the like can be used.

  The vinyl monomer and / or acrylic monomer having a crosslinkable functional group in a) ii) reacts with the crosslinking agent so that the cohesive strength of the adhesive does not break at high temperature or high humidity. It acts to impart cohesive force or adhesive strength due to chemical bonds.

  The vinyl monomer and / or acrylic monomer having a crosslinkable functional group is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, Monomers having a hydroxy group such as 2-hydroxyethylene glycol (meth) acrylate, or 2-hydroxypropylene glycol (meth) acrylate; or acrylic acid, (meth) acrylic acid, acrylic acid dimer, itaconic acid, A monomer having a carboxyl group such as maleic acid or maleic anhydride can be used alone or in admixture of two or more.

  The vinyl monomer and / or acrylic monomer having a crosslinkable functional group is preferably contained in an acrylic copolymer in an amount of 0.1 to 10% by weight, and the content is 0.1% by weight. If it is less than 10% by weight, the cohesive failure is likely to occur under high temperature or high humidity conditions, and the effect of improving the adhesive strength is reduced. As a cause of this, there is a problem that the flow characteristics are reduced and the stress relaxation characteristics are lowered due to an increase in cohesive force.

  Components that induce bubbles such as volatile components and reaction residues in the pressure-sensitive adhesive are preferably used after sufficiently removed. If the crosslink density or molecular weight is too low and the elastic modulus of the adhesive is too low, small bubbles that exist between the glass plate and the adhesive layer at a high temperature become large, and there is a risk of forming scatterers inside the adhesive layer. In addition, when an adhesive having an excessively high elastic modulus is used for a long period of time, a peeling phenomenon may occur at an end portion of the adhesive sheet due to an excessive crosslinking reaction.

  In addition, the viscoelastic properties of the pressure-sensitive adhesive mainly depend on the molecular weight of the polymer chain, the molecular weight distribution, or the molecular structure of the polymer chain, and in particular, are determined by the molecular weight, and thus the acrylic copolymer used in the present invention. The weight average molecular weight of the polymer is preferably 800,000 to 2,000,000, which can be produced through a normal radical copolymerization process.

  The acrylic copolymer comprising the above components can be produced by a usual method such as a solution polymerization method, a photopolymerization method, a bulk polymerization method, a suspension polymerization method, or an emulsion polymerization method. It is preferable to manufacture by. At this time, the polymerization temperature is 50 to 140 ° C., and the initiator is preferably mixed in a state where the monomers are uniformly mixed.

  The polyfunctional cross-linking agent b) used in the present invention reacts with a carboxyl group, a hydroxyl group, etc., and acts to increase the cohesive strength of the pressure-sensitive adhesive.

  As the polyfunctional crosslinking agent, an isocyanate compound, an epoxy compound, an aziridine compound, a metal chelate compound, and the like can be used, and it is particularly preferable to use an isocyanate crosslinking agent.

  As the isocyanate compound, toluene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoform diisocyanate, tetramethylxylene diisocyanate, naphthalene diisocyanate, or a reaction product thereof with a polyol such as trimethylolpropane is used. be able to.

  As the epoxy compound, ethylene glycol diglycidyl ether, triglycidyl ether, trimethylolpropane triglycidyl ether, N, N, N ′, N′-tetraglycidylethylenediamine, glycerin diglycidyl ether, or the like can be used.

  The aziridine-based compound includes N, N′-toluene-2,4-bis (1-aziridinecarboxyde), N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxydo), triethylenemelamine Bisisoprotaloyl-1- (2-methylaziridine), tri-1-aziridinylphosphine oxide, and the like can be used.

  The metal chelate compound may be a compound in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, or vanadium is coordinated to acetylacetone or ethyl acetoacetate.

  In order to achieve a uniform coating operation, the multifunctional crosslinking agent as described above needs to hardly cause a functional group crosslinking reaction of the crosslinking agent in the blending process applied for forming the adhesive layer. When the coating operation is completed and a drying and aging process is performed, a crosslinked structure is formed, and an adhesive layer having elasticity and strong cohesive force can be obtained. At this time, due to the strong cohesive force of the pressure-sensitive adhesive, pressure-sensitive adhesive properties such as durability reliability and cutting properties are improved.

  The polyfunctional crosslinking agent as described above is preferably contained in an amount of 0.01 to 10 parts by weight with respect to 100 parts by weight of the acrylic copolymer. It has excellent cohesive force, has no effect on adhesion durability such as bubbles or peeling, and has an effect of excellent durability reliability.

  The organosilane compound represented by Chemical Formula 1 of c) used in the present invention is used in a pressure-sensitive adhesive composition and has excellent initial adhesive strength when adhered to glass, and adheres at high temperature or high temperature and high humidity. The force does not increase excessively, and acts to prevent the pressure-sensitive adhesive from remaining on the substrate during re-peeling.

  As the organosilane compound represented by the chemical formula 1, the same ones as described above can be used.

  The organosilane compound represented by the chemical formula 1 is preferably contained in an amount of 0.01 to 5 parts by weight with respect to 100 parts by weight of the acrylic copolymer, and when the content is less than 0.01 parts by weight, There is a problem that the effect of increasing the adhesive strength with glass is weak under high temperature or high humidity conditions, and when it exceeds 5 parts by weight, bubbles and delamination occur due to excessive use, and durability reliability decreases. There is a problem.

  The organosilane compound represented by Chemical Formula 1 as described above can be added and used in the blending step after polymerization of the acrylic copolymer, or added during the acrylic copolymer production step. It can also be used.

  The pressure-sensitive adhesive composition of the present invention composed of the components as described above can further contain a tackifying resin, if necessary, in order to adjust the pressure-sensitive adhesive performance.

  The tackifying resin is (hydrogenated) hydrocarbon-based resin, (hydrogenated) rosin resin, (hydrogenated) rosin ester resin, (hydrogenated) terpene resin, (hydrogenated) terpene phenol resin, polymerized rosin resin, Alternatively, a polymerized rosin ester resin or the like can be used alone or in admixture of two or more.

  The tackifying resin is preferably contained in an amount of 1 to 100 parts by weight with respect to 100 parts by weight of the acrylic copolymer. When the content exceeds 100 parts by weight, the compatibility or cohesion of the adhesive is increased. Since it may be lowered, it is necessary to add it with care.

  In addition, the pressure-sensitive adhesive composition of the present invention can be prepared by using an acrylic plasticizer, a low molecular weight material, an epoxy resin, a curing agent, an ultraviolet stabilizer, an antioxidant, a toning agent, a reinforcing agent, a filler, an extinguishing agent, if necessary. Additives such as foaming agents or surfactants can further be used.

  The acrylic pressure-sensitive adhesive composition of the present invention comprising the components as described above can be produced by a usual method, and specifically can be produced by a method such as heat curing or photocuring.

  The pressure-sensitive adhesive composition of the present invention comprising the above components preferably has a cross-linking density of 5 to 95% in view of optimum physical properties. The cross-linking density means a numerical value obtained by weight% of the amount of a portion in which a cross-linked structure that is not dissolved in a solvent is formed through a generally known method for measuring the gel content of an acrylic pressure-sensitive adhesive. When the cross-linking density of the pressure-sensitive adhesive composition is less than 5%, the cohesive strength of the pressure-sensitive adhesive is reduced, causing problems in adhesive durability such as bubbles or peeling. There is a problem that the performance is lowered.

  The present invention also provides a polarizing plate comprising the pressure-sensitive adhesive composition as described above as a pressure-sensitive adhesive layer of a polarizing film. The polarizing plate is formed from the pressure-sensitive adhesive composition on one or both sides of the polarizing film. A pressure-sensitive adhesive layer.

  There is no particular limitation on the polarizing film or the polarizing element constituting the polarizing plate. For example, the polarizing film is obtained by stretching a polarizing film such as iodine or a dichroic dye in a film made of a polyvinyl alcohol resin. The manufactured film etc. can be used and there is no restriction | limiting in particular also in the thickness of these polarizing films, Normal thickness can be formed. At this time, as the polyvinyl alcohol resin, polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, and a saponified product of ethylene and vinyl acetate copolymer can be used.

  On both sides of the polarizing film, cellulose film such as triacetyl cellulose, polycarbonate film, polyester film such as polyethylene terephthalate, polyethersulfone film, polyethylene, polypropylene, polyolefin having cyclic or norbornene structure, ethylene propylene A multilayer film in which a protective film such as a polymer such as a polymer is laminated can be formed. At this time, the thickness of these protective films is not particularly limited, and a normal thickness can be formed.

  The method for forming the pressure-sensitive adhesive layer on the polarizing film as described above is not particularly limited. For example, the method of applying and drying the pressure-sensitive adhesive directly on the surface of the polarizing film using a bar coater, For example, a method in which the pressure-sensitive adhesive layer formed on the surface of the peelable substrate is transferred to the surface of the polarizing film and aged after being applied to the surface of the peelable substrate and dried.

  In addition, the polarizing plate of the present invention as described above is laminated with one or more kinds of layers that provide additional functions such as a protective layer, a reflective layer, an antiglare layer, a retardation plate, a wide viewing angle compensation film, or a luminance improvement. May be.

  The polarizing plate to which the pressure-sensitive adhesive of the present invention is applied can be applied to a normal liquid crystal display device, and the type of the liquid crystal panel is not particularly limited. Preferably, a liquid crystal display device including a liquid crystal panel in which the polarizing plate to which the pressure-sensitive adhesive is applied is bonded to one surface or both surfaces of the liquid crystal cell can be configured.

  The pressure-sensitive adhesive composition of the present invention as described above is used for industrial sheets, particularly reflective sheets, structural pressure-sensitive adhesive sheets, photographic pressure-sensitive adhesive sheets, lane display pressure-sensitive adhesive sheets, optical pressure-sensitive adhesive products, and electronic component pressure-sensitive adhesives. it can. In addition, it goes without saying that it can be similarly applied to application fields having the same concept of action, such as laminate products having a multilayer structure, that is, general commercial adhesive sheet products, medical patches, heat activated pressure sensitive adhesives, etc. .

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, the scope of the present invention is not limited to these Examples.

Example 1
(Manufacture of acrylic copolymer)
In a 1 L reactor provided with a cooling device so that the temperature of the nitrogen gas can be refluxed easily, 98.1 parts by weight of n-butyl acrylate (BA), 1.4 parts by weight of acrylic acid (AA), -A monomer mixture consisting of 0.5 parts by weight of hydroxyethyl methacrylate (2-HEMA) was added, and then 100 parts by weight of ethyl acetate (EAc) was added as a solvent. The reaction mixture was then heated to 62 ° C. After the mixture was homogenized, 0.07 part by weight of azobisisobutyronitrile (AIBN) was added as a reaction initiator and reacted for 8 hours to obtain an acrylic copolymer having a weight average molecular weight of 1,200,000. A coalescence was produced.

(Production of organosilane compounds)
In a 1 L reactor equipped with a thermometer and a condenser, 200 mL of THF, 40 g (0.319 mol) of alkyl cyanoacetate and 40 g (0.327 mol) of trimethoxysilane were added, and the temperature was raised to 60 ° C., and then chloroplatinic acid 0.05 g was added and reacted for 4 hours. After completion of the reaction, the solvent and unreacted substances were removed and vacuum distillation was performed to obtain 73 g of cyanoacetoxypropyltrimethoxysilane (Chemical Formula 2). At this time, the yield was 91%.

(Mixing process)
To 100 parts by weight of the prepared acrylic copolymer, 0.5 part by weight of tolylene diisocyanate adduct (TMP-TDI) of trimethylolpropane as a crosslinking agent and the prepared cyanoacetoxypropyltrimethoxysilane (chemical formula 2 ) 1.0 part by weight was added, diluted to an appropriate concentration in consideration of coating properties, mixed uniformly, then coated on a release paper and dried to produce a uniform adhesive layer of 25 μm.

(Plywood process)
The prepared adhesive layer was subjected to adhesive processing on an 185 μm thick iodine-type polarizing plate, and then stored for 4 days at a temperature of 23 ° C. and a humidity of 55% for a sufficient aging process.

  The polarizing plate obtained as described above was cut into an appropriate size and used for evaluation.

Example 2
(Manufacture of acrylic copolymer)
The same operation as in Example 1 was performed.

(Production of organosilane compounds)
In a 1 L reactor equipped with a thermometer, a condenser, and a dropping glass, 200 mL of diethyl ether and 11 g (0.11 mol) of cyanoacetyl chloride were added and stirred at room temperature in a nitrogen atmosphere. 20 g (0.104 mol) of N-methylaminopropylmethoxysilane and 11 g (0.14 mol) of pyridine were gradually added to 100 mL of diethyl ether using a dropping glass. The reaction product was stirred at room temperature for 2 hours, and then the precipitated pyridine salt was removed to remove the solvent and unreacted material, followed by vacuum distillation to obtain N-methyl-N- (3-trimethoxysilylpropyl) cyano. 21 g of acetamide (Chemical formula 3) was obtained. At this time, the yield was 75%.

(Mixing process)
The same procedure as in Example 1 was conducted except that N-methyl-N- (3-trimethoxysilylpropyl) cyanoacetamide (Chemical Formula 3) prepared above was used instead of cyanoacetoxypropyltrimethoxysilane. It was.

Example 3
In the compounding process of Example 1, 0.5 parts by weight of cyanoacetoxypropyltrimethoxysilane (Chemical Formula 2) prepared in Example 1 and N-methyl-N- (prepared in Example 2) were used as silane compounds. The test was conducted in the same manner as in Example 1 except that 0.5 part by weight of 3-trimethoxysilylpropyl) cyanoacetamide (Chemical Formula 3) was used.

Comparative Example 1
In the blending process of Example 1, the test was performed in the same manner as in Example 1 except that 3-glycidoxypropyltrimethoxysilane was used as the silane compound instead of cyanoacetoxypropyltrimethoxysilane. It was.

Comparative Example 2
In the blending process of Example 1, the test was performed in the same manner as in Example 1 except that cyanoacetoxypropyltrimethoxysilane was not used as the silane compound.

  Using the polarizing plates produced in Examples 1 to 3 and Comparative Examples 1 and 2, glass adhesive strength, adhesive strength under heat and moisture heat resistance conditions, and removability were evaluated by the following methods. Is shown in Table 1.

B) Durability Reliability-The polarizing plate (90 mm x 70 mm) produced in Examples 1-3 and Comparative Examples 1-2 was crossed on both sides of a glass substrate (110 mm x 90 mm x 0.7 mm) and the optical absorption axis was crossed. Adhered as a finished state. The pressure applied at this time was 5 kg / cm ² and was performed in a clean room so as not to generate bubbles and foreign matters. Thereafter, the sample was allowed to stand for 1,000 hours under conditions of 60 ° C. and 90% relative humidity, and then whether or not bubbles or peeling occurred was observed, and durability reliability was measured according to the following evaluation criteria.

  B) Glass Adhesive Strength—After the polarizing plates produced in Examples 1 to 3 and Comparative Examples 1 and 2 were aged at room temperature (23 ° C., 60% RH) for 7 days, each polarizing plate was 1 inch × After cutting to 6 inches, using a 2 kg rubber roller, it adhered to a 0.7 mm-thick non-alkali glass, stored at room temperature, and then measured the initial adhesive force after 1 hour. Further, in order to observe the degree of increase in adhesive strength under high temperature or high temperature / high humidity conditions, the temperature was 10 hours at 80 ° C., 60 ° C., 90% R.D. After leaving for 12 hours under the H condition, the adhesive strength was measured. At this time, the adhesive strength was measured by using a tensile tester and measuring the peel strength at a speed of 300 mm / min and an angle of 180 °.

  C) Re-peelability—After the polarizing plates (90 mm × 70 mm) produced in Examples 1 to 3 and Comparative Examples 1 and 2 were attached to a glass substrate (110 mm × 90 mm × 0.7 mm), 10 Time, 60 ° C., 90% R.D. Aged for 12 hours under H condition. Then, after leaving at room temperature for 1 hour, the polarizing plate was peeled from the glass, and the removability was measured according to the following evaluation criteria.

  As shown in Table 1 above, in the case of Examples 1 to 3 containing the novel organosilane compound represented by Chemical Formula 1 of the present invention, compared to Comparative Example 1 or 2, the initial adhesive strength is increased when adhering to the glass. It was found that the adhesive strength did not increase excessively even under high temperature or high temperature / humidity, and that the pressure-sensitive adhesive did not remain on the substrate during re-peeling.

  Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

[The invention's effect]
The pressure-sensitive adhesive composition according to the present invention can be used for the purpose of improving the adhesiveness between the resin layer made of a matrix resin and the substrate, and particularly when contained in the pressure-sensitive adhesive for polarizing plate of a liquid crystal display device, Adhesiveness with glass substrate is improved, and it contains a new organosilane compound that hardly changes over time even under high temperature and high humidity. The adhesive force does not increase excessively, and there is an effect that the pressure-sensitive adhesive does not remain on the substrate at the time of re-peeling.

Claims (13)

A pressure-sensitive adhesive resin composition comprising an organosilane compound represented by the following chemical formula 1.

(In the above formula, R ₁ , R ₂ , and R ₃ are each independently hydrogen or an alkyl group having 1 to 3 carbon atoms, and X is —NR ₄ — (where R ₄ is hydrogen or A C 1-3 alkyl group), an oxygen atom, or a sulfur atom, n is an integer of 3-10, and j is an integer of 1-3. a) i) 90 to 99.9% by weight of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and ii) a vinyl monomer and / or acrylic having a crosslinkable functional group 100 parts by weight of an acrylic copolymer obtained by copolymerizing 0.1 to 10% by weight of a monomer.
b) 0.01 to 10 parts by weight of a polyfunctional crosslinking agent; and c) 0.01 to 5 parts by weight of the organosilane compound represented by Chemical Formula 1;
The pressure-sensitive adhesive resin composition according to claim 1, comprising:  The organosilane compound is prepared by reacting 1-alkenyl cyanoacetate and trialkoxysilane in the presence of a chloroplatinic acid catalyst, or cyanoacetyl chloride and N-alkylaminoalkyltrialkoxy in the presence of a tertiary amine. The pressure-sensitive adhesive resin composition according to claim 1, which is produced by reacting The organic silane compound is cyanoacetoxypropyltrimethoxysilane represented by the following chemical formula 2 or N-methyl-N- (3-trimethoxysilylpropyl) cyanoacetamide represented by the following chemical formula 3. The pressure-sensitive adhesive resin composition according to claim 1 or 2.

  A) i) a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms is butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) ) Acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, n-octyl methacrylate, isooctyl (meth) acrylate, and isononyl (meth) acrylate The pressure-sensitive adhesive resin composition according to claim 2, wherein at least one selected from the group consisting of:   The vinyl monomer and / or acrylic monomer having a crosslinkable functional group in a) ii) is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl. (Meth) acrylate, 2-hydroxyethylene glycol (meth) acrylate, 2-hydroxypropylene glycol (meth) acrylate, acrylic acid, (meth) acrylic acid, acrylic acid dimer, itaconic acid, maleic acid, and maleic anhydride The pressure-sensitive adhesive composition according to claim 2, wherein at least one kind is selected from the group consisting of products.   The polyfunctional crosslinking agent of b) is selected from the group consisting of an isocyanate compound, an epoxy compound, an aziridine compound, and a metal chelate compound, according to claim 2. Adhesive composition.   The pressure-sensitive adhesive composition is (hydrogenated) hydrocarbon resin, (hydrogenated) rosin resin, (hydrogenated) rosin ester resin, (hydrogenated) terpene resin, (hydrogenated) terpene phenol resin, polymerized rosin resin, And 1 to 100 parts by weight of a tackifier resin selected from the group consisting of a polymerized rosin ester resin and 100 parts by weight of an acrylic copolymer. Adhesive composition.   The pressure-sensitive adhesive composition comprises an acrylic plasticizer, a low molecular weight material, an epoxy resin, a curing agent, an ultraviolet stabilizer, an antioxidant, a toning agent, a reinforcing agent, a filler, an antifoaming agent, and a surfactant. The pressure-sensitive adhesive composition according to claim 2, further comprising one or more additives selected from the group.   The pressure-sensitive adhesive composition according to claim 1 or 2, wherein the pressure-sensitive adhesive composition has a crosslinking density of 5 to 95%.   A polarizing plate comprising the pressure-sensitive adhesive composition according to claim 1 as a pressure-sensitive adhesive layer on one or both sides of a polarizing film.   The polarizing plate further includes one or more layers selected from the group consisting of a protective layer, a reflective layer, an antiglare layer, a retardation plate, a wide viewing angle compensation film, and a brightness enhancement film. Item 12. The polarizing plate according to Item 11.   A liquid crystal display device comprising a liquid crystal panel in which the polarizing plate according to claim 11 is bonded to one surface or both surfaces of a liquid crystal cell.