WO2017052231A1

WO2017052231A1 - Polarizer protective film, polarizing plate, and method for manufacturing polarizing plate

Info

Publication number: WO2017052231A1
Application number: PCT/KR2016/010590
Authority: WO
Inventors: 서정현; 장영래; 김헌; 김혜민
Original assignee: 주식회사 엘지화학
Priority date: 2015-09-22
Filing date: 2016-09-22
Publication date: 2017-03-30

Abstract

The present invention relates to: a polarizer protective film comprising a binder resin layer having a cross-linkage formed by a poly(C₂-C₄ alkylene glycol)-modified polyfunctional urethane (meth)acrylate-based polymer and a bifunctional or more polyfunctional (meth)acrylate-based compound; a polarizing plate comprising the polarizer protective film; and a method for manufacturing a polarizing plate, the method comprising a step for forming the polarizer protective film.

Description

【Specification】

[Name of invention]

Method of manufacturing polarizer protective film, polarizing plate and polarizing plate

Technical Field

Related Application (s) and Mutual Quotes

This application claims the benefit of priority based on Korean Patent Application No. 10-2015-0133891 of September 22, 2015 and Korean Patent Application No. 10-2016-0121215 of September 22, 2016. All content disclosed in the literature is included as part of this specification.

TECHNICAL FIELD This invention relates to the manufacturing method of a polarizer protective film, a polarizing plate, and a polarizing plate.

[Technique to become background of invention]

Liquid crystal displays (LCDs) are one of the most widely used flat panel displays. In general, a liquid crystal display has a structure in which a liquid crystal layer is enclosed between a TFT (Thin Film Transistor) array substrate and a color filter substrate. When an electric field is applied to the electrodes on the array substrate and the color filter substrate, the arrangement of the liquid crystal molecules of the liquid crystal layer enclosed therebetween is changed to display an image by using the electric field.

On the other hand, a polarizing tube is provided outside the array substrate and the color filter substrate. The polarizer may control polarization by selectively transmitting light in a specific direction among light incident from the backlight and light passing through the liquid crystal layer. The polarizing plate generally has a structure in which a protective film for supporting and protecting the polarizer is adhered to a polarizer capable of polarizing light in a specific direction.

As the protective film, a polymer film such as triacetyl cellulose (TAC) is used. However, when the TAC film is used alone, the surface hardness is weak and vulnerable to humidity, and thus a method of adding a functional coating layer to increase the surface hardness and secure wear resistance is used. However, the additional use of such functional coatings increases the overall thickness of the protective film, which not only meets the thinning requirements of electronic devices, The coating may cause curls or cracks in the film.

On the other hand, in a display device having a large screen having a thin thickness, a diffusive layer (Di f fus i on Layer) having irregularities or patterns on the surface has a small distance from the lower flat plate, for example, 1 to 3 간격. As described above, the TAC film does not have a layered surface hardness or wear resistance, so that the polarizer protective film is worn or scratched by the diffusion layer.

[Content of invention]

Problem to be solved

The present invention is to provide a polarizer protective film that can prevent the degradation of the physical properties and optical properties due to wear or scratch of the surface and can implement a layered flexibility to suit the mass production process.

Moreover, this invention is providing the polarizing tube containing the said polarizer protective film.

Moreover, this invention is providing the method of manufacturing the polarizing plate containing the said polarizer protective film.

[Measures of problem]

In the present specification, a binder resin layer in which a poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer and a bifunctional or higher polyfunctional (meth) acrylate-based compound forms a crosslink. A polarizer having a weight ratio of the bifunctional or higher polyfunctional (meth) acrylate-based compound to the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer; A protective film is provided.

In the present specification, the polarizer; And a polarizer protective film.

In addition, in the present specification, poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer; Bifunctional or higher polyfunctional (meth) acrylate compounds; And photocuring the coating composition comprising a photoinitiator to form a polarizer protective film; And on one side of the polarizer Laminating and bonding the polarizer protective film, wherein the bifunctional or higher polyfunctional (meth) acrylate based on the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer There is provided a method for producing a polarizing plate, wherein the weight ratio of the compound is from 1 to 20.

Hereinafter, a method of manufacturing a polarizer protective film, a polarizing plate, and a polarizing plate according to a specific embodiment of the present invention will be described in more detail. As described above, according to one embodiment of the present invention, a poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer and a bifunctional or higher polyfunctional (meth) acrylate-based compound crosslink A bifunctional or higher polyfunctional (meth) acrylate-based compound of the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer, including a binder resin layer forming a bond The polarizer protective film of the weight ratio of 1-20 may be provided.

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer has good flexibility, and maintains the manganese length of the crosslinked structure in the binder resin layer at a relatively long level, the binder A high level of elasticity can be developed in the resin layer. Due to such a high degree of elasticity, even if damage such as scratches occurs due to an external physical stimulus on the polarizer protective film, the damage portion is gradually filled by elasticity, so that the polarizer protective film may exhibit excellent self-healing properties. Accordingly, the polarizer protective film may have a thin thickness but may prevent degradation of physical properties and optical properties due to abrasion or scratching of a surface, and may be implemented in a flexible manner to be suitable for a mass production process.

The binder resin layer is a poly (carbon number 2 to 4 of the carbon number 2 to 4 in order to have a mechanical property such as higher wear resistance and scratch resistance and improved optical properties while ensuring the self-resilience to the surface when the final polarizer protective film is scratched Alkylene glycol) multifunctional or higher polyfunctional polyfunctional urethane (meth) acrylate-based polymers The weight ratio of the (meth) acrylate compound may be 1 to 20, or 5 to 15.

The weight ratio of the bifunctional or higher polyfunctional (meth) acrylate compound to the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate polymer is 1 to 20, or 5 to 15 When out of the range, for example, when the weight ratio is less than 1, the polarizer protective film may be difficult to secure sufficient scratch resistance or surface hardness, and may be difficult to have stability against sudden temperature changes. In addition, when the weight ratio exceeds 20, a bizarre effect from the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer, for example, self-resilience or improved mechanical properties Implementation of optical properties and the like can be difficult.

On the other hand, the binder resin layer is a cross-linking of the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer and bifunctional or more than one polyfunctional (meth) acrylate-based compound through photocuring It can be prepared by forming a.

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer has a trifunctional or more than three functional urethane bonds, the poly (alkylene glycol having 2 to 4 carbon atoms) modified via the urethane bond (Meth) acrylate type compounds are respectively bonded to each of the urethane bonds. At least two of the bonded poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds may include poly (alkylene glycol having 2 to 4 carbon atoms) repeating units having different repeating numbers. (E.g., 2 to 4 poly (alkylene glycols having 2 to 4 carbon atoms) containing different repeating poly (alkylene glycols having 2 to 4 carbon atoms) repeating units with 3 to 6 functional urethane bonds. ) Modified (meth) acrylate-based compound can be bonded

ΛΛ ㅁ 八

On the other hand, the above-mentioned urethane bond reaction can proceed according to the conventional urethane reaction conditions. For example, the urethane reaction is about 20 to 100 ° C It can be made by stirring for 1 to 10 hours, it can be carried out in the presence of a metal-containing catalyst such as tin, such as DBTDL (Dibutyl t in di aurate). More specific examples of the poly (alkylene glycols having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymers include polyethylene glycol-modified polyfunctional urethane (meth) acrylate-based polymers or polypropylene glycol-modified polyfunctional urethanes. A (meth) acrylate type polymer etc. can be mentioned, These can be used individually or these mixtures can also be used. More suitably, in order to further improve the elongation, self-healing properties and the like of the polarizer protective film, the polyethylene glycol-modified polyfunctional urethane (meth) acrylate-based polymer and polypropylene glycol-modified polyfunctional urethane (meth) acrylate-based Polymers can be mixed and used.

More specifically, the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer, trifunctional or more than polyfunctional isocyanate compound; And at least two poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds comprising poly (alkylene glycol having 2 to 4 carbon atoms) repeating units at different repeating numbers; It may be a reaction to the liver. For example, two or more poly (alkylene glycols having 2 to 4 carbon atoms) modifications containing the polyfunctional isocyanate compound having at least three functional groups and a poly (alkylene glycol having 2 to 4 carbon atoms) repeating units at different repeating numbers A urethane reaction of the (meth) acrylate-based compound may form the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer. As a result of the urethane reaction, each isocyanate group of the polyhydric isocyanate compound and a hydroxyl group at the end of a poly (alkylene glycol having 2 to 4 carbon atoms) repeating units are connected to each other while forming a urethane bond to have a polymer having the above-described structure and properties. Can be obtained.

The polyisocyanate compound is a ligomer of a diisocyanate compound, a polymer of a diisocyanate compound, a cyclic multimer of a diisocyanate compound, a hexamethylene di i socyanate i socyanurate, an isophorone di ⁰ isocyanatomethyl carbonate isocyanurate (Isophorone di i i socyanate socyanurate), a toluene 2, 6一 It may be at least one selected from the group consisting of diisocyanate isocyanurate, triisocyanate compound and isomers thereof, and various trifunctional or higher polyvalent isocyanate compounds may be used.

In addition, among specific examples of the polyvalent isocyanate compound, the oligomers, polymers, cyclic multimers or isocyanurates of the diisocyanate compounds may be formed from conventional aliphatic or aromatic diisocyanate compounds, and commercially available diisocyanates. A compound such as ligolimer (for example, Aekyung Chemical's DN980S, which is a trimer of HDI, etc.) may be obtained and used. More specific examples of such diisocyanate compounds include ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-nuclemethylene diisocyanate (HDI), 1,12-dodecane diisocyanate, cyclobutane-1,3 -Diisocyanate, cyclonucleic acid -1,3- diisocyanate, cyclohexane -1 '4-diisocyanate, 1-isocyanato-3,3, 5-trimethyl -5-isocyanatomethyl-cyclonucleic acid, 2,4-nucleohydroluene diisocyanate, 2,6-nucleohydrohydroene diisocyanate, nucleohydro-1,3-phenylene diisocyanate, nucleohydro-1,4-phenylene diisocyanate, perhydro-2 , 4'-diphenylmethane diisocyanate, perhydro-4,4'-diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4'phenylene diisocyanate, 4,4'-stilbene di Iso City Anate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate (T0DI), toluene 2,4-diisocyanate, toluene 2,6-diisocyanate (TDI), diphenylmethane-2 , 4'- diisocyanate (MDI), 2, 2'-diphenylmethane diisocyanate (MDI), diphenylmethane-4,4'- diisocyanate (MDI), isophorone diisocyanate (IPDI), etc. are mentioned. have. The two or more poly (alkylene glycol having 2 to 4 carbon atoms) modified (meth) acrylate-based compound may each have a number average molecular weight of about 200 to 1000, or about 250 to 800, 2 to 10, or 4 And poly (alkylene glycols having 2 to 4 carbon atoms) repeating units having a repeating number of 6 to 6, respectively.

In addition, each of the poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds may have different repeating numbers within the above-described range. It may include a poly (alkylene glycol having 2 to 4 carbon atoms) having a repeating unit, and thus may have a different molecular weight.

Specifically, the difference in number average molecular weight between at least two of the poly (alkylene glycol having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds bonded to the urethane bond may be 100 to 500. Such number average molecular weight can be measured with a conventionally known method such as a gas chromatograph-mass spectrometer for the modified (meth) acrylate-based compound.

In a more specific example, the poly (alkylene glycol having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds, poly (alkyl having 2 to 4 carbon atoms) at a number average molecular weight of about 100 to 400 and the repeating number thereof Lenglycol) compounds having a repeating unit and a compound having a poly (carbon alkyl having 2 to 4 carbon atoms) repeating units having a number average molecular weight of about 400 to 1000 and a repeating number thereof may be used, respectively.

The binder resin layer may contain other known components exhibiting appropriate elasticity.

It may also include more. For example, the binder resin layer may further include a polycarbonate modified bifunctional urethane (meth) acrylate-based polymer. The polycarbonate-modified bifunctional urethane (meth) acrylate-based polymer may be a polymer having a bifunctional or more than two-functional urethane bond and a polycarbonate-modified (meth) acrylate-based compound bonded to each other through the urethane bond. In addition, the binder resin layer may further include polyrotaxane modified with polyrotaxane or other functional groups or compounds. As the polycarbonate modified bifunctional urethane (meth) acrylate-based polymer or polyrotaxane is further included in the binder resin layer, the elongation and self-healing properties of the polarizer protective film may be further improved. have.

The bifunctional or higher polyfunctional (meth) acrylate-based compound is a trifunctional urethane acrylate, 9-ethylene glycol diacrylate (9-EGDA), bisphenol A epoxy acrylate, polyether triacrylate, pentaerythriri Pentaerythr i tol tr i / tetraacrylate (PETA), At least one member selected from the group consisting of dipentaerythritol hexa-acrylate (DPHA), trimethylolpropane triacrylate (TMPTA) and hexamethylene diacrylate (HDDA) It may include. On the other hand, according to another embodiment of the invention, a polarizer; And a polarizer protective film; may be provided.

The content of the polarizer protective film includes all of the above-described content with respect to the polarizing film of the embodiment.

The polarizer exhibits a property of extracting only light vibrating in one direction from incident light while vibrating in various directions. This property can be achieved by stretching polyvinyl alcohol (PVA) absorbing iodine with strong tension. For example, more specifically, swelling to swell the PVA film in an aqueous solution, dyeing with a dichroic substance imparting polarization to the swelled PVA film, stretching the dyed PVA film The polarizer may be formed through a stretching step of arranging the dichroic dye materials side by side in the stretching direction, and a complementary color step of correcting the color of the PVA film subjected to the stretching step. However, the polarizer included in the polarizing plate of the embodiment is not limited to the above-described polyvinyl alcohol (PVA).

It may further include an adhesive layer positioned between the polarizer and the protective film. The adhesive layer may include a polarizer adhesive, which may have transparency and maintain polarization characteristics of the polarizer. Usable adhesives are not particularly limited as long as they are known in the art. For example, a one-component or two-component polyvinyl alcohol (PVA) adhesive, an acrylic adhesive, a polyurethane adhesive, an epoxy adhesive, a styrene butadiene rubber (SBR) adhesive, a hot melt adhesive, and the like, but are not limited thereto. no.

The thickness of the adhesive layer may vary depending on the characteristics of the polarizing plate, for example, in the range of about 0.1 to about 10 η, or about 0.1 to about 5 Can be.

The polarizing plate may further include a second polarizer protective film formed on one surface of the polarizer. The polarizer protective film of the above-described embodiment is attached to one surface of the polarizer, and a polarizer protective film such as TAC or the polarizer protective film of the embodiment is commonly attached to the other surface of the polarizer as the second polarizer protective film. have.

The thickness of the polarizer protective film is 1 to 100, the thickness of the polarizer may be 5 urn to 300. Meanwhile, according to another embodiment of the present invention, a poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer; Bifunctional or higher polyfunctional (meth) acrylate compounds; And photocuring the coating composition comprising a photoinitiator to form a polarizer protective film; And laminating the polarizer protective film on one surface of the polarizer, and attaching the polarizer protective film. The bifunctional or higher polyfunctional urethane (meth) acrylate-based polymer of the poly (alkylene glycol having 2 to 4 carbon atoms) modified poly (2) A weight ratio of the functional (meth) acrylate-based compound is 1 to 20, there may be provided a method for producing a polarizing plate.

The polarizer protective film may be formed by applying the coating composition on a predetermined substrate or a release film and photocuring.

As described above, in order to ensure that the polarizer protective film manufactured by the manufacturing method of the polarizing plate has a mechanical property such as higher abrasion resistance and scratch resistance and improved optical properties while ensuring self-resilience to the surface when a scratch occurs, the poly The alkylene glycol having 2 to 4 carbon atoms may be 1 to 20, or 5 to 15, by weight ratio of the bifunctional or higher polyfunctional (meth) acrylate compound to the modified polyfunctional urethane (meth) acrylate polymer. .

In the manufacturing method of the polarizing plate is not through the method of directly forming the polarizer protective film on the polarizer, and is prepared by applying and curing on a separate substrate or a release film relatively easy to remove, the "viewed coating" The composition can be more easily peeled off in the form of a film and used as a polarizer protective film.

In addition, the polarizer protective film prepared as described above exhibits a low retardation value and can secure high hardness without deterioration of optical properties such as light transmittance and haze. The substrate or the release film may be removed by selectively peeling off or after attaching the protective film to the polarizer after curing of the resin composition.

The method of applying the coating composition is not particularly limited as long as it can be used in the art to which the present technology belongs, for example, bar coating method, knife coating method, coating method, blade coating method, die coating method, micro gravure coating Method, comma coating method, slot die coating method, lip coating method, or solution casting method.

The coating thickness of the coating composition is not limited, and for example, may be applied so that the thickness of the polarizer protective film formed after the drying and curing process is about 1 urn to 100 / m.

The protective coating may be formed by irradiating ultraviolet rays to the applied coating composition to perform a photocuring reaction. Before irradiating the self-rays, the coating surface of the coating composition may be flattened and dried to volatilize the solvent included in the composition.

The irradiation amount of ultraviolet rays may be, for example, about 20 to about 600 mJ / cm ² . It does not specifically limit as a light source of ultraviolet irradiation, For example, a high pressure mercury lamp, a metal halide lamp, a black light fluorescent lamp, etc. can be used.

As described above, the poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer has good flexibility, and maintains the manganese length of the crosslinked structure at a relatively long level in the binder resin layer. Thus, a high level of elasticity can be expressed in the polarizer protective film. Due to such a high degree of elasticity, even if a scratch round damage occurs due to an external physical stimulus on the polarizer protective film, the damage portion is gradually filled by elasticity, so that the polarizer protective film may exhibit excellent self-healing properties. Accordingly, the polarizer protective film may have a thin thickness but may prevent degradation of physical properties and optical properties due to abrasion or scratching of a surface, and may be implemented in a flexible manner to be suitable for a mass production process.

The binder resin layer is a poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer and a bifunctional or more than one polyfunctional (meth) acrylate-based compound to form a crosslink through the photocuring It can be prepared by.

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer has a trifunctional or more than three functional urethane bonds, and the poly (alkylene glycol having 2 to 4 carbon atoms) through the urethane bond Each of the modified (meth) acrylate-based compounds is bonded to each other, and at least two of the poly (C 2-4 .alkylene glycol) -modified (meth) acrylate-based compounds bonded to the respective urethane bonds are different from each other. It may include a poly (alkylene glycol having 2 to 4 carbon atoms) repeating unit having a repeating number.

In addition, each poly (alkylene glycol having 2 to 4 carbon atoms) modification

The (meth) acrylate-based compound may include poly (alkylene glycol having 2 to 4 carbon atoms) repeating units having different repeating numbers within the above-described range, and thus may have different molecular weights.

Specifically, the difference in number average molecular weight between at least two of the poly (alkylene glycol having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds bonded to the urethane bond may be 100 to 500.

On the other hand, the above-mentioned urethane bond reaction can proceed according to the usual urethane reaction conditions. For example, the urethane reaction can be made by stirring for about 1 to 10 hours at about 20 to 100 ° C, it can be carried out in the presence of a metal-containing catalyst such as tin, such as DBTDUDibutyl t in di aurate). Examples of the photoinitiator include benzophenone compounds, acetophenone compounds, biimidazole compounds, triazine compounds, oxime compounds, or mixtures thereof, and more specific examples thereof include benzophenone and benzoyl methyl benzo. Benzoate (Benzoyl methyl benzoate), Acetophenone, 2,4-diethyl thioxanthone (2, 4-diehtyl thioxanthone), 2-chloro thioxanthone, ethyl ant hraqui none, 1-hydride Hydroxy cyclonucleophenyl ketone (1— Hydr oxy-cy c 1 ohexy 1 -pheny 1 -ke t one, commercially available Irgacure 184 from Ciba) or 2-hydroxy-2-methyl-1-phenyl—propanone (2-Hydroxy-2-methyl-l-pheny 1 -pr opan-l-one) etc. are mentioned.

The coating composition is an organic solvent; Or at least one additive selected from the group consisting of inorganic nanoparticles, surfactants, leveling agents and dispersion stabilizers.

Specific examples of the organic solvent are not limited, and examples thereof include ketone-based organic solvents such as methyl isobutyl ketone, methyl ethyl ketone, and dimethyl ketone; Organic solvents such as alcohols such as isopropyl alcohol, isobutyl alcohol or normal butyl alcohol; Acetate organic solvents such as ethyl acetate or normal butyl acetate; Ethyl cellulose cellosolve (ethyl cel lusolve) or butyl cellosolve cellulose (cel lusolve butyl), such as cellular cellosolve may be used an organic solvent such ^as, for.

Additives such as surfactants, leveling agents or dispersion stabilizers can be used without any limitation, by preparing or commercially available components previously known to be usable in compositions for coating layer formation. Specific examples of the inorganic nanoparticles are not limited, and for example, silica nanoparticles having a particle diameter of about 5 to 50 nm and black to about 10 to 40 nm may be used.

In addition, the coating composition may include 5 to 75% by weight of the aforementioned organic solvent. In addition, the coating composition may include 0.01 to 20% by weight of the additive described above.

【Effects of the Invention】

In the present specification, it is possible to prevent degradation of physical and optical properties due to surface abrasion or scratching and is sufficient to be suitable for mass production processes. Provided are a polarizer protective film, a method of manufacturing the same, and a polarizing plate capable of implementing flexibility.

[Brief Description of Drawings]

FIG. 1 shows, in Preparation Example 1, a comparison of FT-IR spectra before and after urethane reaction for the production of a polyethylene glycol-modified polyfunctional urethane (meth) acrylate art binder.

[Specific contents to carry out invention]

The invention is explained in more detail in the following examples. However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited by the following examples.

[Production example]

Preparation Example 1 Preparation of Polyethylene Glycol Modified Polyfunctional Urethane (meth) acrylate Binder

Aekyung Chemical's DN980S, an H13I-based trimer, is used as a trifunctional or higher polyfunctional isocyanate compound, and is a polyethylene glycol modified (meth) acrylate-based ^' compound, including different repeating numbers of polyethylene glycol repeating units with different average numbers Polyethylene glycol mono acrylate (Mn = 300) and polyethylene glycol mono acrylate (Mn = 500) having a molecular weight were used, respectively.

40 g of such a polyisocyanate compound, 30 g of polyethylene glycol mono acrylate (Mn = 300), and 30 g of polyethylene glycol mono acrylate (Mn = 500) were added to DBTDUDibutyl t in di l aurate) O. It was mixed with lg and 200 g of methyl ethyl ketone, and stirred at 60 ° C. for about 5 hours to proceed with the urethane reaction.

By the completion of this urethane reaction, the polyethyleneglycol modified polyfunctional urethane (meth) acrylate type binder of manufacture example 1 was manufactured. The progress of the urethane reaction and the production of the binder was confirmed through FT-IR. For reference, FT-IR spectra before and after the urethane reaction are shown in FIG. 1. Referring to Figure 1, by confirming that the peak derived from the isocyanate group (-NC0) appearing at the position of about 2268.5cm ^_1 disappears, it can be confirmed whether the progress of the urethane reaction and the production of the binder. Preparation Example 2: Polypropylene Glycol Modified Polyfunctional Urethane

Preparation of (meth) acrylate binder

Trifunctional of DN980S of Aekyung Chemical, an HDI trimer _. Polypropylene glycol mono acrylate (Mn), which is used as the polyvalent isocyanate compound and has a different number average molecular weight, including polypropylene glycol repeating units of different repeating numbers, as a polypropylene glycol modified (meth) acrylate compound = 400) and polypropylene glycol mono acrylate (Mn = 600), respectively.

40 g of such polyisocyanate compound, 40 g of polypropylene glycol mono acrylate (Mn = 400), 40 g of polypropylene glycol mono acrylate (Mn = 600) was added to 0.15 g of DBTDUDibutyl t in di laurate) and methyl ethyl ketone ( mixed with 300 g of methyl ethyl ketone, approx. 60 ° C

After stirring for 5 hours to proceed urethane reaction.

By the end of this urethane reaction, the polypropylene glycol modified polyfunctional urethane (meth) acrylate type binder of manufacture example 2 was manufactured. The progress of the urethane reaction and the formation of the binder was confirmed through the same as in Preparation Example 1 whether the peak derived from the isocyanate group (-NC0) appearing at the position of about 2268.501 ^ through FT—IR. Comparative Production Example 1 Preparation of Polyethylene Glycol Modified Polyfunctional Urethane (meth) acrylate-Based Binder

40 g of DN980S (trifunctional or higher polyvalent isocyanate compound) of Aekyung Chemical which is an HDI-based trimer and 70 g of polyethylene glycol mono acrylate (Mn = 300) were added to DBTDL (Dibutyl t in di laurate) O. mixed with lg and 200 g of methyl ethyl ketone, about 5 at 60 ^o C The reaction was allowed to proceed with urethane reaction.

By the end of this urethane reaction, the polyethyleneglycol modified polyfunctional urethane (meth) acrylate type binder of the comparative manufacture example 1 was manufactured. The progress of the urethane reaction and the production of the binder was confirmed through FT-IR in the same manner as in Example 1. Comparative Production Example 2 Preparation of Polyethylene Glycol Modified Polyfunctional Urethane (meth) acrylate-Based Binder

40 g of DN980S (trifunctional or higher polyvalent isocyanate compound) of Aekyung Chemical, which is an HDI-based trimer, and 80 g of polypropylene glycol mono acrylate (Mn = 600) were added to 15 g of methyl butyl diurate (DBTDL) and methyl ethyl ketone. (methyl ethyl ketone), combined with 300 g, approx. 60 ^o C

After stirring for 5 hours, the urethane reaction was performed.

By the end of this urethane reaction, the polyethyleneglycol modified polyfunctional urethane (meth) acrylate type binder of the comparative manufacture example 2 was manufactured. The progress of the urethane reaction and the production of the binder was confirmed through FT-IR in the same manner as in Example 1. Comparative Production Example 3 Preparation of Polyethylene Glycol Modified Polyfunctional Urethane (meth) acrylate-Based Binder

40 g of DN980S (trifunctional or higher polyvalent isocyanate compound) of Aekyung Chemical, an HDI-based trimer, and 80 g of polypropylene glycol mono acrylate (Mn = 200) were added to DBTDU Dibutyl t in di aurate, 15 g and methyl ethyl ketone (methyl). ethyl ketone) was combined with 300 g and stirred at 60 ° C. for about 5 hours to proceed urethane reaction.

By the end of this urethane reaction, the polyethyleneglycol modified polyfunctional urethane (meth) acrylate type binder of the comparative manufacture example 3 was manufactured. The progress of the urethane reaction and the production of the binder was confirmed through FT-IR in the same manner as in Example 1. Comparative Production Example 4 Preparation of Polyethylene Glycol Modified Polyfunctional Urethane (meth) acrylate-Based Binder

40 g of DN980S (trifunctional or higher polyvalent isocyanate compound) of Aekyung Chemical, which is an HDI-based trimer, and 80 g of polypropylene glycol mono acrylate (Μη = 1, 000) were added to DBTDL (Dibutyl t in di aurate) of 0.1 g and methyl. Compatible with 300 g of ethyl ethyl ketone, approx. 60 ° C

After stirring for 5 hours to proceed urethane reaction.

By the end of this urethane reaction, the polyethyleneglycol modified polyfunctional urethane (meth) acrylate type binder of the comparative manufacture example 4 was manufactured. The progress of the urethane reaction and the production of the binder was confirmed through FT-IR in the same manner as in Example 1.

Example: Production of Polarizer Protective Film and Polarizing Plate

Example 1

(1) Preparation of polarizer protective film forming composition

As the polyethyleneglycol-modified polyfunctional urethane (meth) acrylate-based binder obtained in Preparation Example 1 and a bifunctional or higher polyfunctional (meth) acrylate-based compound, dipentaerythrite was replaced with nucleoacrylate (Dipentaerythr i tol Hexacrylate; DPHA). A binder-forming composition was prepared by mixing at a weight ratio of 1: 8.

And, with respect to 100 parts by weight of the binder-forming composition, 2 parts by weight of the UV initiator (Irgacure 184), 5 parts by weight of the leveling agent (tego glide 270, Evonik) and 35 parts by weight of methyl ethyl ketone were mixed A coating composition of 1 was prepared.

(2) Preparation of Polarizer Protective Film

After coating the coating composition of Example 1 to a thickness of 30 to the PET release film, and dried for 2 minutes at 60 ° C Aubon and irradiated with ultraviolet light of lOOmJ / cuf to prepare a polarizer protective film having a self-healing properties. (3) Preparation of Polarizing Plate

Using the acrylic adhesive (thickness: about 1), the prepared polarizer protective film was laminated by laminating with a polyvinyl alcohol (PVA) film, and the PET release film was peeled off. Then, the other side of the polyvinyl alcohol (PVA) film to which the polarizer protective film is not attached is laminated by attaching a triacetyl cellulose (TAC) layer of thickness using an acrylic adhesive (thickness: about 1) to attach the polarizing plate. Was prepared. Example 2

Polyethyleneglycol-modified polyfunctional urethane obtained in Production Example 2

Except having used the (meth) acrylate type binder, the composition for polarizer protective film formation, the polarizer protective film, and the polarizing plate were produced by the same method as Example 1. Example 3

(1) Preparation of Composition for Polarizer Protective Film Formation

The coating composition was prepared in the same manner as in Example 1.

(2) Preparation of Polarizer Protective Film

After coating the prepared coating composition on a PET release film with a thickness of 60, and dried for 2 minutes in an oven at 60 ° C. to prepare a polarizer protective film having a self-recovery characteristics by irradiating ultraviolet light of 100mJ / cirf.

(3) Preparation of Polarizing Plate

Using the acrylic adhesive (thickness: about 1 kPa), the polarizer protective film prepared above was laminated with a polyvinyl alcohol (PVA) film to be bonded, and the PET release film was peeled off. Then, by laminating a triacetyl cellulose (TAC) film having a thickness of 60 with an acrylic adhesive (thickness: about 1) to the other side of the polyvinyl alcohol (PVA) film to which the polarizer protective film is not attached, A polarizing plate was prepared. Example 4

(1) Preparation of polarizer protective film forming composition

Polyethyleneglycol-modified polyfunctional urethane (meth) acrylate-based binder obtained in Production Example 1, polyethyleneglycol-modified polyfunctional urethane (meth) acrylate-based binder and bifunctional or higher polyfunctional (meth) acrylate-based compound obtained in Production Example 2 As a pentaerythryce, Dipentaerythr i tol Hexacrylate (DPHA) was mixed at a weight ratio of 1: 1 to prepare a composition for forming a binder.

Then, the coating composition of Example 4 was prepared by mixing 2 parts by weight of UV initiator (Irgacure 184), 5 parts by weight of leveling agent, and 35 parts by weight of methyl ethyl ketone with respect to 100 parts by weight of the composition for forming a binder.

(2) Production of polarizer protective film and polarizing plate

Except for using the coating composition of Example 4, a composition for forming a polarizer protective film, a polarizer protective film and a polarizing plate was prepared in the same manner as in Example 1.

[Comparative Example]

Comparative Example 1

Using an acrylic adhesive (thickness: about 1), a 60-acetyl triacetyl cellulose (TAC) film [polarizer protective film] was laminated with a polyvinyl alcohol (PVA) film and laminated. On the other side of the polyvinyl alcohol (PVA) film, a 60 판 thick triacetyl cellulose (TAC) film was laminated using an acrylic adhesive (thickness: about) and bonded to prepare a polarizing plate.

A composition for forming a polarizer protective film, a polarizer protective film, and a polarizing plate were manufactured in the same manner as in Example 1 except that the polyethylene glycol modified polyfunctional urethane (meth) acrylate-based binder obtained in Comparative Production Example 1 was used. Comparative Example 3

A composition for forming a polarizer protective film, a polarizer protective film, and a polarizing plate were prepared in the same manner as in Example 1, except that the polyethylene glycol modified polyfunctional urethane (meth) acrylate-based binder obtained in Comparative Production Example 2 was used. Comparative Example 4

As the polyethyleneglycol-modified polyfunctional urethane (meth) acrylate-based binder obtained in Preparation Example 1 and a bifunctional or higher polyfunctional (meth) acrylate-based compound, dipentaerythrite was replaced with nucleoacrylate (Dipentaerythr i tol Hexacrylate; DPHA). It mixed with the weight ratio of 2: 1, the point which produced the composition for binder formation was produced, and the composition for polarizer protective film formation, the polarizer protective film, and the polarizing plate were produced by the same method as Example 1. Comparative Example 5

Dipentaerythr to nuxaacrylate (Dipentaerythr i tol

Hexacryl ate; 2 parts by weight of UV initiator (Irgacure 184), 5 parts by weight of leveling agent (tego gl i de 270, Evonik) and 35 parts by weight of methyl ethyl ketone, were mixed to 100 parts by weight of DPHA), except that the coating composition was prepared. Was prepared in the same manner as in Example 1, the composition for forming a polarizer protective film, the polarizer protective film and the polarizing plate. Comparative Example 6

Polyethyleneglycol-modified polyfunctional urethane obtained in Comparative Production Example 3

Except having used the (meth) acrylate type binder, the composition for polarizer protective film formation, the polarizer protective film, and the polarizing plate were produced by the same method as Example 1. Comparative Example 7 A composition for forming a polarizer protective film, a polarizer protective film, and a polarizing plate were manufactured in the same manner as in Example 1 except that the polyethylene glycol modified polyfunctional urethane (meth) acrylate-based binder obtained in Comparative Production Example 4 was used.

Experimental Example

1. Measurement of scratch resistance

After applying a constant load to the brightness-enhanced diffusion film and rubbing the surface of each of the polarizer protective films of the above Examples and Comparative Examples in 10 reciprocations, the load generated on the surface of the polarizer protective film was compared.

[0K: No scratch at the load I NG: Scratch at the load]

2. Measurement of copper scratch self-healing characteristics

After the scratches were generated on the surfaces of the polarizer protective films of the examples and the comparative examples using copper feeding, the time for the scratches to be restored was measured. Specifically, after laminating the Bl ack PET film on the back of the polarizer protective film, the dust on the surface of the film was removed using nitrogen wind. Then, after generating a scratch on the surface of the film under a three-wavelength lamp, the time until the scratch disappeared was measured. At this time, whether the scratch occurred was determined by whether the light of the three-wavelength lamp is reflected by the scratch and visually confirmed, and whether the scratch disappears or not is determined by whether the light of the three-wavelength lamp is visually confirmed. 3. Pencil Hardness Measurement

The pencil hardness with respect to the surface of the polarizer protective film of an Example and a comparative example was measured under the constant load 500g using the pencil hardness meter (layer book tech). Specifically, the hardness was measured using a standard pencil (Mitsubishi Co., Ltd.) having a hardness of 6B to 9H, and repeatedly measured 5 times with a measuring length of 3cm. At this time, the scratch at 0.5 cm at the beginning of the measuring section is the force at which the load begins to be applied. It may not work evenly, and surface hardness was determined using scratches at the latter 2.5 cm.

4. Thermal stratification test

After laminating the polarizing plates obtained in Examples and Comparative Examples with an adhesive on a glass plate, the adhesive was completed by placing them in a light-shielded space at room temperature for 24 hours. In this way, six test samples were prepared for each polarizer. Then, the test sample was exposed to 80 ° C of silver for 30 minutes, then exposed to -30 ^° C for 30 minutes, and then returned to 80 ° C by applying a temperature change condition of 1 cycle. , 100 cycles were repeated.

The sample was observed after the 100 cycle repetition, and the deformation of the polarizer, the crack occurrence, and the adhesion state of the film were evaluated. At this time, the deformation of the polarizer was determined by whether the polarizer axis is bent or not, and the occurrence of cracks was determined by whether the light is transmitted through a gap in the polarizer. It was determined whether the lifting phenomenon occurred.

When any of the deformation of the polarizer, crack occurrence, and the adhesion state of the film is a problem occurs, it was evaluated as NG, and when there was no problem, it was evaluated as 0K. Physical property evaluation results measured above are summarized in Table 1 and Table 2 below.

[Table 1]

(500 g)

Thermal Shock Test OK OK OK OK

Table 2

As shown in Table 1 and Table 2, the polarizer protective film obtained in the example has a high scratch resistance compared to the polarizer protective film of the comparative example and can prevent the degradation of physical properties and optical properties due to the wear or scratch of the surface It has been confirmed that the surface has a self restoring force when scratches are generated.

In addition, it is confirmed that the polarizer protective film of the embodiment not only has excellent pencil hardness, but also has excellent stability that does not cause a problem in adhesion of the film or deform the internal and external shapes and structures even after a large temperature change that occurs repeatedly. It became.

Claims

[Claim]

[Claim 1]

A binder resin layer in which a poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer and a bifunctional or higher polyfunctional (meth) acrylate-based compound form a crosslink;

The polarizer protective film whose weight ratio of the said bifunctional or more polyfunctional (meth) acrylate type compound with respect to the said poly (alkylene glycol of 2 to 4 carbon number) modified polyfunctional urethane (meth) acrylate type polymer is 1-20.

[Claim 2]

The method of claim 1,

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer has a trifunctional or more than a trifunctional urethane bond,

Poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds are bonded to each other through the urethane bond,

At least two of the poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds bonded to the urethane bonds each have a different number of repetitions (the alkylene glycols having 2 to 4 carbon atoms) The polarizer protective film containing a repeating unit.

[Claim 3]

The method of claim 2,

The difference in the number average molecular weight between at least two of the above-mentioned urethane bond poly (alkylene glycol having 2 to 4 carbon atoms) modified (meth) acrylate-based compound is 100 to 500,

Polarizer protective film.

[Claim 4]

The method of claim 1,

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (Meth) acrylate-based polymer is polyethylene glycol modified polyfunctional urethane

(Meth) acrylate-based polymer and polypropylene glycol modified polyfunctional urethane

A polarizer protective film containing at least one selected from the group consisting of (meth) acrylate-based polymers.

[Claim 5]

In U,

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymer,

Trifunctional or higher polyvalent isocyanate compounds; And at least two poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds comprising poly (alkylene glycol having 2 to 4 carbon atoms) repeating units at different repeating numbers; The polarizer protective film which is a counterproduct of liver. [Claim 6]

The method of claim 5,

The polyisocyanate-based compound is a ligomer of the diisocyanate compound, a polymer of the diisocyanate compound, a cyclic multimer of the diisocyanate compound, hexamethylene di i socyanate i socyanurate, isophorone diisocyanate I sophorone di i socyanate i socyanurate, toluene 2,

6— A polarizer protective film, which is at least one member selected from the group consisting of diisocyanate isocyanurate, triisocyanate compounds and isomers thereof.

[Claim 7]

The method of claim 5,

The at least two poly (alkylene glycols having 2 to 4 carbon atoms) modified (meth) acrylate-based compounds including poly (alkylene glycols having 2 to 4 carbon atoms) repeating units at different repeating numbers may be 200 to 1000, respectively. The polarizer protective film which has a number average molecular weight.

[Claim 8]

The method of claim 1,

The binder resin layer further comprises a polycarbonate modified bifunctional urethane (meth) acrylate-based polymer, polarizer protective film.

[Claim 9]

The method of claim 8,

The polycarbonate-modified bifunctional urethane (meth) acrylate-based polymer is a polymer having a bifunctional or more than two functional urethane bond and a polymer in which a polycarbonate-modified (meth) acrylate-based compound is bonded to each other through the urethane bond.

[Claim 10]

The method of claim 1,

The bifunctional or higher polyfunctional (meth) acrylate-based compound is a polyfunctional urethane acrylate, 9-ethylene glycol diacrylate (9-EGDA), bisphenol A epoxy acrylate, polyether triacrylate, pentaeryeri H Lye / tetraacrylate (pentaerythritol tri / tetraacrylate; PETA), dipentaerythritol hexa-acrylate (DPHA), trimethylolpropane triacrylate (TMPTA) and nucleomethylene diacrylate Polarizer protective film containing one or more selected from the group consisting of (hexamethylene diacrylate; HDDA).

[Claim 11]

According to claim 1,

The poly (alkylene glycol having 2 to 4 carbon atoms) modified polyfunctional urethane

The weight ratio of the bifunctional or higher polyfunctional (meth) acrylate compound to the (meth) acrylate polymer is 5 to 15, Polarizer protective film.

[Claim 12]

Polarizer; And a polarizer protective film of claim 1.

[Claim 13]

The method of claim 12,

The polarizer further comprises an adhesive layer located between the polarizer and the protective film.

[Claim 14]

The method of claim 12,

Further comprising a second polarizer protective film formed on one surface of the polarizer, polarizing plate.

[Claim 15]

The method of claim 12,

The polarizer protective film has a thickness of 1 to 100,

The thickness of the polarizer is 5 / to 300, the polarizing plate.

[Claim 16]

Poly (alkylene glycols having 2 to 4 carbon atoms) modified polyfunctional urethane (meth) acrylate-based polymers; Bifunctional or higher polyfunctional (meth) acrylate compounds; And photocuring the coating composition comprising a photoinitiator to form a polarizer protective film; And

Laminating and bonding the polarizer protective film to one surface of the polarizer,

The manufacturing method of the polarizing plate whose weight ratio of the said bifunctional or more polyfunctional (meth) acrylate type compound with respect to a (meth) acrylate type polymer is 1-20. [Claim 17]

The method of claim 16,