KR102008187B1 - Composition for barrier layer, polarizing plate comprising the same and optical display apparatus comprising the same - Google Patents

Abstract

A composition for a barrier layer comprising an elastomer, an epoxy compound, a (meth) acrylate compound, and a photoinitiator, wherein the elastomer is 1% by weight of the total of the elastomer, the epoxy compound, and the (meth) acrylate compound based on solid content To 20% by weight, the barrier layer composition is a modulus of 1000MPa or more at 85 ℃ after photocuring, the barrier layer composition, a polarizing plate comprising the same and an optical display device comprising the same.

Description

Composition for barrier layer, polarizing plate comprising the same, and an optical display including the same {COMPOSITION FOR BARRIER LAYER, POLARIZING PLATE COMPRISING THE SAME AND OPTICAL DISPLAY APPARATUS COMPRISING THE SAME}

The present invention relates to a barrier layer composition, a polarizing plate including the same, and an optical display device including the same.

The liquid crystal display device includes a liquid crystal panel and polarizing plates formed on both surfaces of the liquid crystal panel, respectively. The polarizing plate includes a polarizer and a protective film formed on both surfaces of the polarizer, respectively. In recent years, a polarizing plate has been thinned by forming a protective film on one surface of the polarizer and forming a coating layer (barrier layer) on the other surface of the polarizer.

In the liquid crystal display device, it is necessary to arrange the polarizing plates on both sides of the glass substrate forming the surface of the liquid crystal panel from the image forming method. As a polarizing plate, what bonded together the transparent protective film for polarizers using triacetyl cellulose etc. with the polyvinyl alcohol-type adhesive on one or both surfaces of the polarizer which consists of a polyvinyl alcohol-type film and dichroic materials, such as iodine, is used. . In addition, the durability required for the polarizing plate is becoming difficult, and high durability in a harsh environment at low temperatures and high temperatures is required (Japanese Patent Laid-Open No. 2006-220732).

An adhesive layer is normally applied to the polarizing plate which provided the transparent protective film on both surfaces of the polarizer, and the adhesive layer is laminated | stacked on the transparent protective film in the said polarizing plate. On the other hand, although the polarizing plate which provided the transparent protective film only in the single side | surface of a polarizer is used from a thinning viewpoint, in the said polarizing plate, an adhesive layer is provided in the other single side of a polarizer. However, in the thin adhesive polarizing plate in which the transparent protective film is provided only on one side of the polarizer, durability is poor and there is a problem that cracks tend to occur in the stretching direction (MD direction) of the polarizer under the harsh environment. In addition, a polarizing plate having a protective film formed on at least one side of the polarizer has been proposed for the problem of thinning (Japanese Patent Application No. 2009-122796).

There are various attempts to protect the polarizer by forming a barrier layer on one side. A pressure-sensitive adhesive polarizing plate is disclosed in which the barrier layer forming agent is a cyanoacrylate forming agent, an epoxy forming agent, an isocyanate forming agent, or an acrylic forming agent (Japanese Patent Application No. 2009-122796). The outside of the polarizing film through the first protective layer and the adhesive layer made of a cured product of the curable resin composition containing an active energy ray-curable compound containing an epoxy-based compound having at least one epoxy group in a molecule laminated on one side of the polarizing film A polarizing plate having a second protective layer made of a thermoplastic resin film laminated on its surface is disclosed (Japanese Patent Application No. 2008-203419).

The problem to be solved by the present invention is to provide a barrier layer composition that can suppress the occurrence of cracks of the polarizer by suppressing the shrinkage of the polarizer under thermal shock conditions.

Another problem to be solved by the present invention is to provide a barrier layer composition capable of realizing a barrier layer of a thin film having good compatibility, storage stability, good coating properties.

Another problem to be solved by the present invention is to provide a barrier layer composition that can increase the durability of the polarizing plate by lowering the rate of change of light transmittance at high temperature and / or high humidity.

Another problem to be solved by the present invention is to provide a barrier layer composition that can implement a barrier layer excellent in adhesion and cutting property to the polarizer.

The barrier layer composition of the present invention is a barrier layer composition comprising an elastomer, an epoxy compound, a (meth) acrylate compound, and a photoinitiator, wherein the elastomer is based on the solid content of the elastomer, the epoxy compound, and the (meth) acrylate compound. 1 to 20% by weight of the total of the compound, the barrier layer composition may have a modulus of 1000MPa or more at 85 ℃ after photocuring.

Polarizing plate of the present invention; And a polarizer and a protective layer are sequentially stacked on one surface of the barrier layer, and the barrier layer may be formed of the barrier layer composition of the present invention.

The optical display device of the present invention may include the polarizing plate of the present invention.

The present invention provides a barrier layer composition that can suppress crack generation of a polarizer by suppressing shrinkage of the polarizer under thermal shock conditions.

The present invention provides a barrier layer composition capable of realizing a barrier layer of a thin film having good compatibility, storage stability, and coating property.

The present invention provides a barrier layer composition that can lower the transmittance change rate at high temperature and high humidity to increase durability of the polarizing plate.

The present invention provides a barrier layer composition capable of implementing a barrier layer having good adhesion to polarizers and excellent cutting properties.

1 is a cross-sectional view of a polarizing plate according to an embodiment of the present invention.
2 is a cross-sectional view of a polarizer according to another embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, it will be described embodiments of the present application in more detail. However, the technology disclosed in the present application is not limited to the embodiments described herein and may be embodied in other forms. It is merely to be understood that the embodiments introduced herein are provided so that the disclosure can be made thorough and complete, and that the spirit of the present application can be fully conveyed to those skilled in the art. In the drawings, the width, thickness, and the like of the components are enlarged in order to clearly express the components of each device. Like reference numerals refer to like elements throughout the drawings.

In the present specification, "upper" and "lower" are defined based on the drawings, and according to a viewpoint, "upper" may be changed to "lower" and "lower" to "upper", and "on" or What is referred to as “on” may include not only the above but also intervening other structures in the middle. On the other hand, what is referred to as "directly on" or "directly on" means not intervening in other structures such as intermediates.

In the present specification, the "modulus" of the barrier layer is a storage modulus, and the modulus is a length x width (30 mm x 10 mm) sample obtained after photocuring the composition for the barrier layer to have a thickness of 10 μm. It is the value measured while heating up to 120 degreeC.

As used herein, "(meth) acryl" refers to acrylic and / or methacryl.

Moisture permeability of the "protective layer" herein is a value measured at 40 ℃ and relative humidity 90% in accordance with KS A1013.

In the present specification, the "in-plane retardation (Re)" and the "thickness retardation (Rth)" of the protective layer are the values measured by the following formulas A and B, respectively:

<Formula A>

Re = (nx-ny) x d

(In Formula A, nx and ny are refractive indices in the slow axis direction and the fast axis direction of the protective layer at wavelength 550 nm, respectively, and d is the thickness of the protective layer (unit: nm).

<Formula B>

Rth = ((nx + ny) / 2-nz) x d

(In Formula B, nx, ny, and nz are refractive indexes in the slow axis direction, the fast axis direction, and the thickness direction of the protective layer, respectively, at a wavelength of 550 nm, and d is the thickness of the protective layer (unit: nm).

The barrier layer composition according to an embodiment of the present invention may include an elastomer, an epoxy compound, a (meth) acrylate compound, and a photoinitiator.

Elastomers are included in the barrier layer composition, preventing the modulus from decreasing by reacting the epoxy compound and the (meth) acrylate compound, respectively, or with each other, increasing the modulus at high temperature, thereby suppressing the shrinkage of the polarizer under thermal shock conditions, thereby causing cracks in the polarizer. It can reduce the occurrence. For example, the barrier layer composition may have a modulus of 1000 MPa or more at 85 ° C. after photocuring. Within this range, shrinkage of the polarizer can be suppressed under thermal shock conditions and the durability at high temperature and high humidity can be increased. Accordingly, the polarizing plate including the barrier layer formed of the barrier layer composition of the present invention may have a maximum crack length of 2 mm or less in the absorption axis direction (generally, machine direction) of the polarizer under thermal shock. In the above range, the crack generation of the polarizer in the thermal shock is low, it is possible to increase the reliability of the polarizing plate. Specifically, the barrier layer composition may have a modulus of 1000 MPa to 1500 MPa at 85 ° C. after photocuring. Within this range, the shrinkage of the polarizer under thermal shock conditions can be suppressed, the adhesion and cutting properties to the polarizer can be good, and the durability and reliability of the polarizing plate can be good.

The elastomer may include an elastomer that is non-reactive in the presence of a photoinitiator for each of an epoxy compound and a (meth) acrylate compound. Since the non-reactive elastomer does not react with the epoxy-based compound or the (meth) acrylate-based compound even during the curing of the barrier layer composition, it is possible to remarkably prevent the modulus from decreasing at high temperatures. In addition, the non-reactive elastomer can minimize the influence of the stress upon curing shrinkage upon curing of the barrier layer composition, thereby suppressing deformation of the barrier layer, thereby suppressing deformation of the polarizer. The term "non-reactive" means that the elastomer does not react with each of the epoxy compound and the (meth) acrylate compound in the presence of a photoinitiator during photocuring of the barrier layer composition.

The elastomer may include an elastomer including a (meth) acrylate-based repeat unit. The elastomer may comprise a block copolymer consisting of a hard segment comprising methacrylate units and a soft segment comprising acrylate units. The hard segment consists of polymethyl methacrylate (PMMA) and has a glass transition temperature of 100 ° C to 120 ° C. The soft segment consists of polybutyl acrylate (PnBA) and a glass transition temperature of -50 ° C to -40 ° C. Can be. The elastomer may have a weight average molecular weight of 10,000 g / mol to 300,000 g / mol. In the above range, it can be used for the barrier layer.

The elastomer may be synthesized by conventional methods known to those skilled in the art, or may include, but is not limited to, one or more of commercially available products such as elastomer kurarity LA4285 (kuraray), elastomer kurarity LB550 (kuraray).

The elastomer may be included in an amount of 1% to 20% by weight based on the solid content of the elastomer, the epoxy compound, and the (meth) acrylate compound. Within this range, the modulus at high temperature after curing of the barrier layer composition is increased to prevent cracking due to thermal shock of the polarizer, the viscosity of the barrier layer composition is too high to prevent compatibility or degradation of applicability, and storage stability is reduced. It can prevent falling and can prevent the cutting and adhesiveness with respect to a polarizer to fall. Preferably, the elastomer may be included in 5% to 20% by weight, 5% to 15% by weight, 5% to 10% by weight of the total of the elastomer, the epoxy compound and the (meth) acrylate-based compound.

The elastomer may be included in an amount of 1 part by weight to 20 parts by weight, for example, 5 parts by weight to 15 parts by weight, based on 100 parts by weight of the epoxy compound. Within this range, the modulus at high temperature after curing of the barrier layer composition is increased to prevent cracking due to thermal shock of the polarizer, the viscosity of the barrier layer composition is too high to prevent compatibility or degradation of applicability, and storage stability is reduced. You can prevent it from falling.

The elastomer may be included in an amount of 20 parts by weight to 100 parts by weight, for example, 30 parts by weight to 100 parts by weight based on 100 parts by weight of the (meth) acrylate compound. In the above range, there may be a high temperature modulus synergistic effect.

The epoxy compound may include an alicyclic epoxy compound.

The alicyclic epoxy compound may be polymerized by a cation initiated by light energy. Of the cycloaliphatic epoxy compounds, bifunctional cycloaliphatic epoxy compounds may be used. The bifunctional alicyclic epoxy compound has a high glass transition temperature of the homopolymer to support the laminated structure between the polarizer and the barrier layer to increase durability, and the interfacial adhesion between the polarizer and the barrier layer with chemical bonding and excellent wettability by the hydroxyl group generated during the reaction. Can increase. The bifunctional alicyclic epoxy compound may have a glass transition temperature of the homopolymer of 150 ° C or higher, for example, 150 ° C to 250 ° C. In the above range, there may be an effect of increasing the glass transition temperature of the barrier layer.

The bifunctional alicyclic epoxy compound is a compound having two alicyclic epoxy groups. The cycloaliphatic epoxy group has a functional group in which an alicyclic group of C3 to C20 is epoxidized, a C2 to C20 alicyclic group having a functional group in which an alicyclic group of C3 to C20 is epoxidized, or a functional group in which an alicyclic group of C3 to C20 is epoxidized It means an alkyl group of C1 to C10. Specifically, an alicyclic epoxy group means at least one of an epoxycyclohexyl group, an epoxycyclopentyl group, and a glycidyl group.

In one embodiment, the bifunctional alicyclic epoxy compound is epoxycyclohexylmethyl epoxycyclohexanecarboxylate, epoxycyclohexane carboxylate of alkanediol, epoxycyclohexylmethyl ester of dicarboxylic acid, epoxy of polyethylene glycol To be cyclohexyl methyl ether type, epoxy cyclohexyl methyl ether type of alkanediol, diepoxy citrispyro type, diepoxy monospiro type, vinyl cyclohexene diepoxide type, epoxy cyclopentine ether type, diepoxy tricyclodecane type compound Can be.

Bifunctional alicyclic epoxy compounds include 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexane carboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-3', 4'-epoxy One or more of -6'-methylcyclohexanecarboxylate, bis (3,4-epoxy-6-methylcyclohexyl) adipate. For example, although the bifunctional alicyclic epoxy-type compound can use brand name CELLOXIDE 2021P (DIACEL company) etc., it is not limited to this.

The alicyclic epoxy compound may be included in an amount of 50% by weight to 90% by weight based on the solid content of the elastomer, the epoxy compound, and the (meth) acrylate compound. In the above range, the modulus of the barrier layer is increased to secure a modulus of 1000 MPa or more at 85 ° C., and the glass transition temperature of the entire barrier layer composition is increased to prevent cracking of the polarizer due to thermal shock and the viscosity of the composition does not increase to a thin film. The barrier layer can be formed and the adhesion to the polarizer can be good. Preferably, the alicyclic epoxy compound may be included in an amount of 60 wt% to 90 wt%, 60 wt% to 80 wt% in the total of the elastomer, the epoxy compound and the (meth) acrylate compound.

The epoxy compound may further include at least one of an aromatic epoxy compound and an aliphatic epoxy compound.

At least one of an aromatic epoxy compound and an aliphatic epoxy compound is bonded in the middle of the curing reaction of the cycloaliphatic epoxy compound to facilitate adjustment of the curing rate of the barrier layer composition, thereby improving the conversion rate of the curing reaction, and Helps improve cohesion In addition, at least one of an aromatic epoxy compound and an aliphatic epoxy compound may prevent excessive increase in the viscosity of the composition for the barrier layer as a reactive diluent.

The aromatic epoxy compound may include at least one of a monofunctional aromatic epoxy compound and a bifunctional aromatic epoxy compound. For example, the aromatic epoxy compound is phenylglycidyl ether, cresyl glycidyl ether, nonylphenylglycidyl ether, and the aromatic epoxy compound is bisphenol A, F, and phenol noblock, cresol noblock, bisphenol A-noblock. , Dichloropentadiene noblock, glycidyl ether of triphenolmethane, triglycidyl paraaminophenol, tetraglycidyl methylene dianiline.

The aliphatic epoxy compound may include at least one of a monofunctional aliphatic epoxy compound and a bifunctional aliphatic epoxy compound. For example, the aliphatic epoxy compound may be ethyl glycidyl ether, butyl glycidyl ether, hexyl glycidyl ether, octyl glycidyl ether, 2-ethylhexyl glycidyl ether, dodecyl glycidyl ether, or octa. Monofunctional aliphatic epoxy compounds such as decylglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentylglycol diglycidyl ether, trimethylolpropane triglycol Cydyl ether, polyethylene glycol diglycidyl ether, glycerin triglycidyl ether, polypropylene glycol diglycidyl ether; Diglycidyl ethers of polyether polyols obtained by adding one or two or more alkylene oxides to aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin; Diglycidyl esters of aliphatic long-chain dibasic acids; Diglycidyl ethers of aliphatic higher alcohols; One or more of the bifunctional aliphatic epoxy type compounds, such as diglycidyl ether of a higher fatty acid, can be included.

At least one of an aromatic epoxy compound and an aliphatic epoxy compound may be included in an amount of 5 wt% to 30 wt% based on the solid content of the elastomer, the epoxy compound, and the (meth) acrylate compound. In the above range, the cohesive force of the composition for the barrier layer is good, the reaction rate of the composition for the barrier layer does not slow down and the crack resistance due to thermal shock may not be reduced. For example, at least one of the aromatic epoxy compound and the aliphatic epoxy compound may be 10% to 30% by weight, 10% to 25% by weight based on the total solids of the elastomer, the epoxy compound, and the (meth) acrylate compound. , 10 wt% to 20 wt%, and 10 wt% to 15 wt%.

The epoxy compound is 70% to 95% by weight, specifically 75% to 95% by weight, more specifically 75% to 90% by weight, based on the total amount of the elastomer, epoxy compound and (meth) acrylate compound based on solids It may be included as. Within this range, the adhesion between the polarizer and the barrier layer can be improved, the crack resistance of the polarizer can be improved, and the cutting property can be improved.

The (meth) acrylate-based compound can be included in the barrier layer composition to lower the viscosity, thereby improving the coating property of the composition, increasing the hardness of the barrier layer, and promoting curing of the barrier layer composition. The (meth) acrylate-based compound may include at least one of a monofunctional (meth) acrylic compound and a bifunctional (meth) acrylic compound.

Monofunctional (meth) acrylic compounds include (meth) acrylates having unsubstituted C1 to C10 alkyl groups, (meth) acrylates having C1 to C10 alkyl groups having at least one hydroxyl group, and alicyclic groups of C3 to C10 It may include (meth) acrylate having, (meth) acrylate having an aryl group of C6 to C20, or (meth) acrylate having an arylalkyl group of C7 to C20. Specifically, the monofunctional (meth) acrylic compound is t-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2 Or 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate , Cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate.

In addition, the monofunctional (meth) acrylic compound is tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, It may also include one or more of ethyl carbitol (meth) acrylate, trimethylolpropane mono (meth) acrylate, pentaerythritol mono (meth) acrylate, phenoxy polyethylene glycol mono (meth) acrylate.

The bifunctional (meth) acrylic compound is an unsubstituted alkylene glycol di (meth) acrylate, a polyoxyalkylene glycol di (meth) acrylate, a halogen-substituted alkylene glycol di (meth) acrylate, or a dialkyl of an aliphatic polyol. Di (meth) acrylate of (meth) acrylate, hydrogenated dicyclopentadiene or tricyclodecanedialkanol, di (meth) acrylate of dioxane glycol or dioxanedialkanol, bisphenol A or bisphenol F alkyl It may comprise one or more of the di (meth) acrylate, bisphenol A or epoxy di (meth) acrylate of bisphenol F of the ethylene oxide adduct.

Specifically, the bifunctional (meth) acrylic compound is ethylene glycol di (meth) acrylate, 1,3-butanedioldi (meth) acrylate, 1,4-butanedioldi (meth) acrylate, 1,6-hexanediol Di (meth) acrylate, 1,9-nonanedioldi (meth) acrylate, neopentylglycoldi (meth) acrylate, trimethylolpropanedi (meth) acrylate, pentaerythritol di (meth) acrylate, Ditrimethylolpropanedi (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate , Polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polytetramethylene glycoldi (meth) acrylate, silicone di (meth) acrylate, hydroxy pivalic acid ester neopentyl Cold di (meth) acrylate, 2,2-bis [4- (meth) acryloyloxyethoxyethoxyphenyl] propane, 2,2-bis [4- (meth) acryloyloxyethoxyethoxycyclo Hexyl] propane, hydrogenated dicyclopentadienyldi (meth) acrylate, tricyclodecanedimethanoldi (meth) acrylate, 1,3-dioxane-2,5-diyldi (meth) acrylate, tris It may comprise one or more of (hydroxyethyl) isocyanurate di (meth) acrylate.

Preferably, the (meth) acrylate-based compound may include a monofunctional or bifunctional (meth) acrylic compound containing one or more hydroxyl groups. This can increase the adhesion between the polarizer and the barrier layer by the action of the hydroxyl group of the polarizer. In addition, mono- or bi-functional (meth) acrylic compounds containing at least one hydroxyl group can be cured stably without inhibiting the curing reaction caused by the moisture of the polarizer, thereby increasing the reliability of the barrier layer. have. Specifically, a monofunctional (meth) acrylic compound containing at least one hydroxyl group is a (meth) acrylate having an alkyl group of C1 to C10 having at least one hydroxyl group, for example 2-hydroxyethyl (meth) acrylate , 2- or 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate.

The (meth) acrylic compound is 1% by weight to 20% by weight, specifically 5% by weight to 20% by weight, more specifically 5% by weight to 15%, based on the total amount of the elastomer, the epoxy compound, and the (meth) acrylate compound based on the solid content It may be included in weight percent. Within this range, the adhesion between the polarizer and the barrier layer can be improved, the crack resistance of the polarizer can be improved, and the cutting property can be improved.

The photoinitiator may comprise one or more of a photoacid generator, a photoradical initiator.

Photo-acid generators can be used those commonly known to those skilled in the art. Specifically, the photoacid generator may use an onium salt containing a cation and an anion. Specifically, the cation is diphenyl iodonium, 4-methoxydiphenyl iodonium, bis (4-methylphenyl) iodonium, bis (4-tert-butylphenyl) iodonium, bis (dodecylphenyl) iodonium, (4 Triarylsulfonium such as diaryl iodonium such as -methylphenyl) [(4- (2-methylpropyl) phenyl) iodonium, triphenylsulfonium, diphenyl-4- (phenylthio) phenylsulfonium, and bis [ 4- (diphenylsulfonio) phenyl] sulfide etc. are mentioned. Specifically, the anion is phosphate (PF ₆ ^-) hexafluoropropane, borates (BF ₄ ^-) tetrafluoroborate, antimonate hexafluorophosphate (SbF ₆ ^-), are Senate hexafluorophosphate (AsF ₆ ^-), hexamethylene Chloro antimonate (SbCl ₆ ⁻ ) and the like.

The photoacid generator may be included in an amount of 0.1 parts by weight to 10 parts by weight, specifically 1 part by weight to 10 parts by weight, based on 100 parts by weight of the total amount of the elastomer, the epoxy compound, and the (meth) acrylate compound. In the above range, it can be sufficiently cured, and it is possible to prevent the residual amount of initiator from remaining to lower the transparency of the barrier layer.

The photoradical initiator may be one known to those skilled in the art. Specifically, the optical radical initiator may use at least one of hydroxyketone, thioxanthone, phosphorus, triazine, acetophenone, benzophenone, benzoin and oxime.

The photoradical initiator may be included in an amount of 0.1 parts by weight to 10 parts by weight, specifically 0.1 parts by weight to 6 parts by weight, based on 100 parts by weight of the total amount of the solid-based elastomer, the epoxy compound, and the (meth) acrylate compound. In the above range, it can be sufficiently cured, and it is possible to prevent the residual amount of initiator from remaining to lower the transparency of the barrier layer.

The photoinitiator may be included in an amount of 1 to 15 parts by weight, for example, 1 to 10 parts by weight of the photoinitiator, based on 100 parts by weight of the total of the elastomer, the epoxy compound, and the (meth) acrylate compound. In the above range, it can be sufficiently cured, and it is possible to prevent the residual amount of initiator from remaining to lower the transparency of the barrier layer.

The barrier layer composition may have a viscosity change rate of 5% or less, for example, 0.1% to 3%. In the above range, the storage stability may be high so that the productivity is good:

<Equation 1>

Viscosity change rate = │V1-V0│V0 x 100

(In Formula 1, V0 is the initial viscosity (unit: cps) at 25 ℃ of the barrier layer composition,

V1 is a viscosity (unit: cps) at 25 ° C. after leaving the composition for a barrier layer at 25 ° C. for 1 week.

The barrier layer composition may further include a solvent-free composition containing no solvent, or a solvent in order to facilitate coating, coating, or processability. Solvents may include, but are not limited to, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, and the like.

The barrier layer composition may further include an additive. The additive may provide additional functionality to the barrier layer. Specifically, the additive may include one or more of a UV absorber, a reaction inhibitor, an adhesion enhancer, a thixotropic imparting agent, a conductivity imparting agent, a color regulator, a stabilizer, an antistatic agent, an antioxidant, and a leveling agent, but is not limited thereto. Do not.

The composition for the barrier layer further includes fine particles to further increase the hardness and mechanical strength of the barrier layer. Specifically, the fine particles contain hygroscopic fine particles, which can further enhance the water barrier effect of the barrier layer.

The fine particles may include, but are not limited to, one or more of silica, aluminum oxide, zirconium oxide, titanium oxide. The fine particles may be surface-treated with an epoxy group, a (meth) acrylate group, or a vinyl group, in whole or in part, in order to increase compatibility. The fine particles are not limited in shape and size. Specifically, the fine particles may include particles having a spherical shape, a plate shape, an amorphous shape, and the like. The fine particles may have an average particle diameter of 1 nm to 200 nm, specifically 8 nm to 50 nm. Within this range, the hardness of the barrier layer can be increased without affecting the surface roughness and transparency of the barrier layer.

The fine particles may be included in 3% by weight to 30% by weight, specifically 5% by weight to 20% by weight of the composition for the solid content barrier layer. Within this range, the hardness of the barrier layer can be increased without affecting the surface roughness and transparency of the barrier layer.

The barrier layer composition may have a viscosity of 5 cP to 200 cP, specifically 10 cP to 150 cP at 25 ° C. In the above range, the barrier layer may be easily formed.

Polarizing plate of the present invention; And a polarizer in which a polarizer and a protective layer are sequentially stacked on one surface of the barrier layer, and the barrier layer may be formed of the barrier layer composition of the present invention.

Hereinafter, a polarizing plate according to an embodiment of the present invention will be described with reference to FIG. 1. 1 is a cross-sectional view of a polarizing plate according to an embodiment of the present invention.

Referring to FIG. 1, the polarizer 100 may include a polarizer 110, a protective layer 120, and a barrier layer 130. The barrier layer 130, the polarizer 110, and the protective layer 120 are sequentially stacked. The barrier layer 130 may be formed of the barrier layer composition of the present invention. The barrier layer 130 is formed directly on the polarizer 110. The "directly formed" means that no other adhesive layer or adhesive layer is interposed between the barrier layer and the polarizer.

The polarizer 100 includes the barrier layer 130, and the polarizer is left at -40 ° C. for 30 minutes, heated at -40 ° C. to 85 ° C., and left at 85 ° C. for 30 minutes as one cycle. The maximum length of the crack in the absorption axis direction may be 2 mm or less. In the above range, the crack generation of the polarizer in the thermal shock is low, thereby increasing the reliability of the polarizing plate.

In addition, the polarization plate 100 may have a light transmittance change rate of 1% or less in the following Equation 2: In the above range, the polarizer may have high durability at high temperature and high humidity, and thus may be used in an optical display device:

<Equation 2>

Transmittance rate of light transmission = │T1-T0│T0 x 100

(Equation 2, T0 is the initial light transmittance of the polarizing plate (unit:%)

T1 is a light transmittance (unit:%) measured after placing the polarizing plate in a chamber at 85 ° C. and 85% relative humidity and leaving it at 25 ° C. for 1 hour after 500 hours.

The polarizing plate 100 may be T1 ≦ T0 in Equation 2, and T1 and T0 may each be 30% or more, specifically, 30% to 50%. Within the above light transmittance range, it can be used in an optical display device.

The polarizer 110 may polarize external light incident to the polarizer 100.

The polarizer 110 may include a polarizer made of a polyvinyl alcohol-based resin film. In one embodiment, the polarizer may be a polyvinyl alcohol polarizer in which at least one of iodine and dichroic dye is adsorbed onto the polyvinyl alcohol resin film. In another embodiment, the polarizer may be a polyene-based polarizer prepared by dehydrating the polyvinyl alcohol-based resin film.

The polyvinyl alcohol-based resin film may have a saponification degree of 85 mol% to 100 mol%, specifically 98 mol% to 100 mol%. The polyvinyl alcohol-based resin film may have a degree of polymerization of 1,000 to 10,000, specifically 1,500 to 10,000. The polyvinyl alcohol-based resin film may have a thickness of 50 μm to 200 μm. Polarizer can be manufactured in the said saponification degree, the polymerization degree, and the thickness range.

Specifically, the polyvinyl alcohol polarizer adsorbs at least one of iodine and dichroic dye on the polyvinyl alcohol resin film, and uniaxially stretches MD (machine direction) at a final drawing ratio of 2 to 8 times, specifically 3 to 6 times. Can be prepared. Stretching can include dry stretching, wet stretching, or a combination thereof. The "final draw ratio" means the ratio of the length of the final polyvinyl alcohol polarizer to the initial length of the polyvinyl alcohol resin film. After stretching, color correction may be further performed by immersion in an aqueous solution of boric acid and an aqueous solution of potassium iodide. Specifically, the polyene polarizer may be prepared by adding an acid catalyst to the polyvinyl alcohol-based resin film and dehydrating and drying the same. The acid catalyst may include an organic acid, an inorganic acid or a mixture thereof containing an aromatic sulfonic acid such as toluenesulfonic acid including para toluenesulfonic acid and the like.

The polarizer 110 may have a thickness of 5 μm to 100 μm, specifically 5 μm to 50 μm. In the above range, it can be used for the polarizing plate.

The protective layer 120 may be formed on one surface of the polarizer 110 to protect the polarizer 110.

The protective layer 120 has a water permeability of 30 g / m ² · 24 hr or less, specifically 1 g / m ² · 24 hr to 20 g / m ² · 24 hr, more specifically 5 g / m ² · 24 hr to 15 g / m ² · 24 hr Can be. By preventing external moisture from penetrating the polarizer in the above range, the durability at high temperature and high humidity of the polarizing plate can be increased, and the durability at high temperature and high humidity of the polarizing plate can be further increased together with the barrier layer.

The protective layer 120 may be a protective coating layer or a protective film.

The protective coating layer may be formed of an active energy ray curable resin composition containing an active energy ray curable compound and a polymerization initiator. The active energy ray curable compound may include at least one of a cationically polymerizable curable compound, a radically polymerizable curable compound, a urethane resin, and a silicone resin. The cationically polymerizable curable compound may be an epoxy compound having at least one epoxy group in a molecule, or an oxetane compound having at least one oxetane ring in a molecule. The radically polymerizable curable compound may be a (meth) acrylic compound having at least one (meth) acryloyloxy group in a molecule. The epoxy compound may be at least one of a hydrogenated epoxy compound, a chain aliphatic epoxy compound, a cyclic aliphatic epoxy compound, and an aromatic epoxy compound. The radically polymerizable curable compound can be obtained by reacting two or more kinds of (meth) acrylate monomers and functional group-containing compounds having at least one (meth) acryloyloxy group in a molecule, and at least two (meth) acryloyl jade in the molecule. A (meth) acrylate oligomer which has timing is mentioned. As a (meth) acrylate monomer, the monofunctional (meth) acrylate monomer which has one (meth) acryloyloxy group in a molecule | numerator, the bifunctional (meth) acrylate which has two (meth) acryloyloxy groups in a molecule | numerator Monomers, and polyfunctional (meth) acrylate monomers having three or more (meth) acryloyloxy groups in the molecule. The (meth) acrylate oligomer may be a urethane (meth) acrylate oligomer, a polyester (meth) acrylate oligomer, an epoxy (meth) acrylate oligomer, or the like. The polymerization initiator can cure the active energy ray curable compound. The polymerization initiator may comprise one or more of a photocationic initiator, a photosensitizer.

Photocationic initiators can be used those commonly known to those skilled in the art. Specifically, the photocationic initiator may use an onium salt containing a cation and an anion. Specifically, the cation is diphenyl iodonium, 4-methoxydiphenyl iodonium, bis (4-methylphenyl) iodonium, bis (4-tert-butylphenyl) iodonium, bis (dodecylphenyl) iodonium, (4 Triarylsulfonium, such as diaryl iodonium, such as -methylphenyl) [(4- (2-methylpropyl) phenyl) iodonium, triphenylsulfonium, diphenyl-4-thiophenoxyphenylsulfonium, and bis [ 4- (diphenylsulfonio) phenyl] sulfide etc. are mentioned. Specifically, the anion includes hexafluorophosphate, tetrafluoroborate, hexafluoroantimonate, hexafluoroarsenate, hexachloroantimonate, and the like. A photosensitizer can be used conventionally known to those skilled in the art. Specifically, the photosensitizer may be used at least one of thioxanthone, phosphorus, triazine, acetophenone, benzophenone, benzoin, oxime. The polymerization initiator may be included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the total active energy ray-curable compound. In the above range, the curing may be sufficiently high mechanical strength and good adhesion to the polarizer. The active energy ray curable resin composition may further include conventional additives such as silicone-based leveling agents, ultraviolet absorbers, antistatic agents, and the like. The additive may be included in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the total active energy ray curable compound. The protective coating layer may be a liquid crystal coating layer.

The protective film may be a non-stretched film or a stretched film. The stretched film may have a range of phase differences to provide additional functions to the polarizer. The stretched film may have an in-plane retardation Re of 5,000 nm or more, specifically 5,000 nm to 15,000 nm, more specifically 6,000 nm to 12,000 nm. The stretched film may have a thickness direction retardation (Rth) of 15,000 nm or less, specifically 5,000 nm to 15,000 nm, more specifically 6,000 nm to 12,000 nm. Within this range, it is possible to prevent the rainbow spots from occurring when using the polarizing plate.

The protective film may be a film formed of an optically transparent resin. Specifically, the resin is a cellulose resin such as triacetyl cellulose, polyethylene terephthalate (PET film), polybutylene terephthalate, polyester resin such as polyethylene naphthalate, polybutylene naphthalate, amorphous cyclic polyolefin (cyclic olefin) cyclic polyolefin resins, polycarbonate resins, polyether sulfone resins, polysulfone resins, polyamide resins, polyimide resins, acyclic-polyolefin resins, and polymethyl meta It may include one or more of polyacrylate-based resin, polyvinyl alcohol-based resin, polyvinyl chloride-based resin, polyvinylidene chloride-based resin including an acrylate resin. In one embodiment of the present invention, the protective layer is preferably a polyester resin such as polyethylene terephthalate (PET film), polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, PET film is most preferred.

Although not shown in FIG. 1, the protective layer 120 may further provide a polarizing plate by further including a functional coating layer on one surface of the protective layer 120. Specifically, the functional coating layer may be one or more of a hard coating layer, an antireflection layer, an anti-fingerprint layer, an antistatic layer, a low reflection layer, but is not limited thereto. The functional coating layer may have a thickness of 1 μm to 100 μm, specifically 1 μm to 50 μm, and more specifically 1 μm to 20 μm. It is possible to provide additional functions to the polarizing plate without affecting the protective layer in the above range, it can be used in the polarizing plate.

In addition, although not shown in Figure 1, if the protective layer 120 is a protective film, by further including a primer layer on the other side of the protective film it may be to better adhere the polarizer 110 and the protective film. If the protective layer is a protective coating layer, the protective layer may be formed directly on the polarizer.

The protective layer 120 may have a thickness of 5 μm to 200 μm, specifically 10 μm to 150 μm, and more specifically 50 μm to 120 μm. In the above range, it can be used for a polarizing plate and can suppress the curvature of a polarizing plate with a barrier layer.

The barrier layer 130 is formed on the other side of the polarizer 110 to protect the polarizer 110 from the surface opposite to the protective film 120 with respect to the polarizer 110 and external moisture penetrates into the polarizer 110. By blocking it, durability of the polarizing plate 100 at high temperature and high humidity can be improved.

The barrier layer 130 is formed directly under the polarizer 110 and has a high adhesiveness to the polarizer 110 so that the barrier layer 130 is directly formed on the polarizer 110 without an adhesive layer, thereby realizing a thinning effect of the polarizing plate 100.

The barrier layer 130 may have a thickness of 20 μm or less, specifically 1 μm to 15 μm, and more specifically 1 μm to 12 μm. In the above range, it can be used for the polarizing plate, having an appropriate thickness for the entire protective layer and the adhesive layer can suppress the warpage of the polarizing plate, it is possible to increase the barrier properties to prevent cracking.

Although not shown in FIG. 1, when the protective layer 120 is a protective film, an adhesive layer may be formed between the protective film and the polarizer to bond the polarizer and the protective film. The adhesive layer may be formed of an adhesive for a water-based or UV photocurable polarizing plate.

Hereinafter, a method of manufacturing a polarizing plate according to an embodiment of the present invention will be described.

The polarizing plate according to the exemplary embodiment of the present invention may be manufactured by forming a protective layer on one surface of the polarizer, applying the composition for the barrier layer to the other surface of the polarizer, and curing the barrier layer composition.

The barrier layer compositions may be applied by conventional coating methods, respectively. Specifically, it may be applied by die coating, gravure coating and the like. Curing can include irradiation with active energy ray in the UV specifically, 100mW / cm ² to ^{2000mW / cm 2, 100mJ / cm} 2 to 1000mJ / cm ^2.

Hereinafter, a polarizer according to another exemplary embodiment of the present invention will be described with reference to FIG. 2. 2 is a cross-sectional view of a polarizer according to another embodiment of the present invention.

Referring to FIG. 2, the polarizer 200 may include a polarizer 110, a protective layer 120, a barrier layer 130, and an adhesive layer 140. Since the adhesive layer 140 is formed on the lower surface of the barrier layer 130, the polarizer 200 may adhere the polarizing plate to the panel for an optical display device such as a liquid crystal panel. Except that the adhesive layer is further formed is substantially the same as the polarizing plate according to an embodiment of the present invention. Therefore, below, only an adhesion layer is demonstrated.

The adhesive layer 140 may be formed on the bottom surface of the barrier layer to adhere the polarizer to the panel. The adhesive layer 140 may have a modulus of 0.1 MPa or less at 25 ° C. Within this range, even if the modulus is high at a high temperature of the barrier layer, thermal contraction expansion of the polarizer can be alleviated. Hard modifiers with modulus greater than 0.1 MPa may adversely affect the shrinkage expansion behavior of the device. The adhesive layer may be formed of a (meth) acrylic, urethane, or silicone pressure sensitive adhesive composition.

An optical display device according to an embodiment of the present invention may include a polarizing plate according to embodiments of the present invention. The optical display device may be a liquid crystal display device, an organic light emitting device display device, or the like, but is not limited thereto.

Hereinafter, the configuration and operation of the present invention through the embodiments of the present invention will be described in more detail. However, the following examples are provided to help the understanding of the present invention, and the scope of the present invention is not limited to the following examples.

Hereinafter, specific specifications of the components used in the Examples and Comparative Examples are as follows.

① Elastomer: kurarity LA4285, kuraray

② Elastomer: kurarity LB550, kuraray

③Epoxy compound: alicyclic epoxy compound, 3 ', 4'-epoxycyclohexane) methyl 3,4-epoxycyclohexylcarboxylate, Celloxide 2021P, Daicel

④ Epoxy compound: aromatic epoxy compound, Phenyl Glycidyl Ether, EX-141, Nagase

⑤Epoxy compound: Aliphatic epoxy compound, 2-Ethylhexyl Glycidyl Ether, EX-121, Nagase

⑥ (meth) acrylate compound: 4-hydroxybutyl acrylate, Sigma-Aldrich

⑦ Mine generator: diphenyl-4- (phenylthio) phenylsulfonium hexafluorophosphate, CPI-100P, San-Apro company

⑧Photoradical initiator: 1-hydroxycyclohexylphenyl ketone, Irgacure 184, BASF Corporation

Example One

10 parts by weight of elastomer, 70 parts by weight of cycloaliphatic epoxy compound, 10 parts by weight of aromatic epoxy compound, 10 parts by weight of (meth) acrylate compound, 6 parts by weight of photoacid generator, 1 part by weight of radical photo initiator, The composition was prepared.

Example  2 to Example  7

In Example 1, a barrier layer composition was prepared in the same manner except for changing the type and / or content of the elastomer, the epoxy compound, the photoacid generator, and the photoradical initiator as shown in Table 1 (unit: parts by weight). It was.

Comparative example  1 to Comparative example  3

In Example 1, a barrier layer composition was prepared in the same manner except for changing the type and / or content of the elastomer, the epoxy compound, the photoacid generator, and the photoradical initiator as shown in Table 1 (unit: parts by weight). It was.

Elastomer Epoxy compounds (Met)
Acrylate Mine generator Photo radical initiator ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ Example 1 - 10 70 10 - 10 6 One Example 2 10 - 60 15 - 15 6 One Example 3 5 - 80 10 - 5 6 One Example 4 5 - 70 10 - 15 6 One Example 5 - 5 70 10 - 15 6 One Example 6 5 - 70 - 10 15 6 One Example 7 5 - 75 - 10 10 6 One Comparative Example 1 5 - 40 40 - 15 6 One Comparative Example 2 - - 70 15 - 15 6 One Comparative Example 3 30 - 60 - - 10 6 One

The physical properties of Table 2 were evaluated for the compositions for barrier layers of Examples and Comparative Examples.

(1) Modulus: After the composition for the barrier layer of the Example and Comparative Example was applied between the release film and photocured under a metal halide lamp 400 mW / cm ² , 1000 mJ / cm ² conditions to prepare a cured sample having a thickness of 10㎛. Cured samples were cut to 30 mm long by 10 mm wide, and the modulus was measured by raising the temperature from 0 ° C. to 120 ° C. at 1 Hz of frequency. Modulus was measured using a DMA Q800 instrument. Modulus was taken at 85 ° C.

(2) Adhesion: A polyvinyl alcohol film (saponification degree: 99.5 mol%, polymerization degree: 2000) having a thickness of 80 µm was immersed in a 0.3% aqueous solution of iodine for dyeing, and then stretched so that the draw ratio was 5.0. Subsequently, the stretched base film was immersed in a boric acid solution and a 2% potassium iodide solution at a concentration of 3% for color correction, and dried at 50 ° C. for 4 minutes to prepare a polarizer (thickness: 18 μm).

PET film (moisture permeability: 10g / m ^{2 at} 24hr, wavelength 550nm, Re: 10,200nm, Rth: 12,000nm, thickness: 80㎛, Toyobo, The moisture permeability is 40 ℃ and 90% relative humidity in accordance with KS A1013 Measured value) One side was corona treated at 250 mJ / cm ² . On the corona-treated surface of the PET film, a UV curable polarizing plate adhesive was applied at a thickness of 2 μm, and one surface of the prepared polarizer was adhered.

On the other side of the polarizer, the barrier layer compositions of Examples and Comparative Examples were applied with a thickness of 3 μm and laminated in a temperature of 22 to 25 ° C. and 20% to 60% relative humidity, so that the metal halide lamp 400 mW / cm ² , 1000 mJ / cm Photocuring was performed under ² conditions to prepare a polarizing plate in which a protective film, a polarizer, and a barrier layer were sequentially stacked. The barrier layer is formed directly on the polarizer.

The prepared polarizing plate was cut into length 100mm x width 25mm, and the cutter blade tip was inserted between the barrier layer of the edge part of a polarizing plate, and a polarizer. ◎ that the tip of the knife does not enter between the barrier layer and the polarizer, ○, that the tip of the knife entered a little, ○, the tip of the knife entered a little, but there was a certain strength, △, △, and that the tip of the knife easily entered, X was evaluated.

(3) Cutting property: The polarizing plate was manufactured by the method similar to (2).

The polarizing plate was punched from the barrier layer side in the size of width x length (500 mm x 500 mm) using a cutter blade. The peeling state of the tip of the four punched polarizing plates was visually observed. (Circle) that the barrier layer did not peel off, (circle) that the barrier layer peeled 1 mm or less, (triangle | delta) that the barrier layer peeled more than 1 mm and 2 mm or less, (triangle | delta) and the barrier layer peeled more than 2 mm were evaluated by X.

(4) Crack length: The polarizing plate was manufactured by the method similar to (2).

A sample was prepared by laminating a length x width (50 mm x 50 mm) polarizing plate on a glass plate. The sample was left at -40 ° C for 30 minutes, heated at -40 ° C to 85 ° C, and left at 85 ° C for 30 minutes as 1cycle to give 100 cycles of thermal shock. The sample was visually confirmed whether cracks were generated by MD of the polarizer in the reflection mode under the fluorescent lamp and the back light mode. The maximum length of cracks that occurred was evaluated.

(5) High temperature, high humidity durability: The polarizing plate was manufactured by the method similar to (2).

The prepared polarizing plate was cut into length x width (25 mm x 25 mm), and laminated in the middle of the slide glass (length x width, 25 mm x 100 mm) to prepare a sample. The initial light transmittance (T0, unit:%) of the polarizing plate was measured using V-7170 (JASCO Corporation). The sample was placed in a chamber at 85 ° C. and 85% relative humidity, and after 500 hours, it was left at 25 ° C. for 1 hour and the light transmittance (T1, unit:%) was measured using V-7170 in the same manner as described above. The light transmittance change rate was calculated according to the following Equation 2. When light transmittance change rate was 1% or less, it evaluated as (circle), more than 1%, and 3% or less, (triangle | delta), and when it exceeded 3%, it evaluated by X.

<Equation 2>

Transmittance rate of light transmission = │T1-T0│T0 x 100

(6) Viscosity change rate: Initial viscosity (V0, unit: cps) was measured using the Physica MCR 501 (Anton Paar company) apparatus at 25 degreeC with respect to the composition for barrier layers of an Example and a comparative example. After leaving the composition for the barrier layer at 25 ° C. for 1 week, the viscosity (V1, unit: cps) was measured at 25 ° C. using a Physica MCR 501 (Anton Paar) device. Using this, the viscosity change rate was calculated by the following formula 1:

<Equation 1>

Viscosity change rate = │V1-V0│V0 x 100

Modulus
(MPa,
＠ 85 ℃) Adhesion Foundation Crack length
(mm) High temperature and high humidity
durability
(＠ 85 ℃, 85%) Viscosity
Rate of change
(%) Example
One 1330 ◎ ◎ 1.2 ◎ 2.8 Example
2 1360 ○ ◎ 1.0 ◎ 2.6 Example
3 1290 ◎ ◎ 0.9 ◎ 2.2 Example
4 1220 ◎ ◎ 0.9 ◎ One Example
5 1120 ◎ ◎ 1.0 ◎ 0.8 Example
6 1210 ◎ ◎ 0.9 ◎ 1.2 Example
7 1200 ◎ ◎ 0.9 ◎ 1.3 Comparative example
One 380 X X 1.1 △ 0.2 Comparative example
2 560 ◎ ○ 2.6 △ 0.7 Comparative example
3 1780 X X 1.3 ◎ 7.1

As shown in Table 2, the barrier layer composition of the present invention has a low viscosity change rate, and thus has good storage stability, lowers the light transmittance change rate at high temperature and / or high humidity, thereby increasing the reconstruction of the polarizing plate, and the adhesion and cutting property to the polarizer. An excellent barrier layer can be formed.

However, Comparative Example 1, which contains an elastomer but has a modulus of 1000 MPa or less at 85 ° C. after photocuring, has poor adhesion and cutting property to the polarizer, and a high light transmittance change rate at high temperature and / or high humidity.

Comparative Example 2, which does not contain an elastomer, exhibited high crack generation of the polarizer, and a high light transmittance change rate at high temperature and / or high humidity.

Comparative Example 3 including the elastomer beyond the scope of the present invention at 85 ℃ after photocuring at least 1000MPa, the adhesiveness and cutting property is not good for the polarizer, the viscosity change rate is high storage stability is not good, Crack generation inhibition was also lower than the present invention.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (14)

It is a composition for barrier layers containing an elastomer, an epoxy compound, a (meth) acrylate type compound, and a photoinitiator,
The barrier layer composition has a modulus of 1000 MPa or more at 85 ° C. after photocuring,
The barrier layer composition is based on solids,
In the sum total of the said elastomer, an epoxy type compound, and a (meth) acrylate type compound
1 wt% to 20 wt% of the elastomer,
70 wt% to 95 wt% of the epoxy-based compound,
1 wt% to 20 wt% of the (meth) acrylate compound,
1 part to 15 parts by weight of the photoinitiator, based on 100 parts by weight of the total of the elastomer, epoxy compound, and (meth) acrylate compound,
The barrier layer composition is a barrier layer composition, the viscosity change rate of the following formula 1 is 5% or less:
<Equation 1>
Viscosity change rate = │V1-V0│V0 x 100
(In Formula 1, V0 is the initial viscosity (unit: cps) at 25 ℃ of the composition for the barrier layer,
V1 is the viscosity at 25 ℃ (unit: cps) after leaving the composition for barrier layer at 25 ℃ for a week.
The composition of claim 1, wherein the elastomer is non-reactive in the presence of the photoinitiator with respect to each of the epoxy-based compound and the (meth) acrylate-based compound.
The composition for barrier layers according to claim 1, wherein the elastomer comprises a block copolymer composed of a hard segment containing a methacrylate unit and a soft segment containing an acrylate unit.
The composition for a barrier layer according to claim 1, wherein the epoxy compound comprises a bifunctional alicyclic epoxy compound.
The composition of claim 4, wherein the epoxy compound further comprises at least one of an aromatic epoxy compound and an aliphatic epoxy compound.
The composition for barrier layers according to claim 1, wherein the (meth) acrylate compound contains a monofunctional or bifunctional (meth) acrylic compound containing at least one hydroxyl group.
delete delete Barrier layer; And a polarizer in which a polarizer and a protective layer are sequentially stacked on one surface of the barrier layer.
The barrier layer is formed of the barrier layer composition of any one of claims 1 to 6.
10. The method of claim 9, wherein the polarizing plate is left for 30 minutes at -40 ℃, the temperature is raised to -85 ℃ to 85 ℃, after 30 cycles to perform a cycle of 100 cycles left for 30 minutes at 85 ℃ in the direction of the absorption axis of the polarizer The polarizing plate whose crack maximum length is 2 mm or less.
The polarizing plate according to claim 9, wherein the protective layer has a moisture permeability of 30 g / m ² · 24 hr or less.
The polarizing plate according to claim 9, wherein the protective layer is a polyester resin system.
The method of claim 9, wherein the adhesive layer is further formed on the other side of the barrier layer,
The adhesive layer has a modulus of 0.1 MPa or less at 25 ° C.
An optical display device comprising the polarizing plate of claim 9.

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