KR20100077798A - Uv curing hard coating composition, polarizing film having anti-smudge using the composition and method of manufacturing hard coating layer - Google Patents

Abstract

PURPOSE: A UV curing hard coating composition is provided to obtain excellent adhesive force with a base film, transparency, scratch resistance, and stain resistance, to prevent rainbow phenomenon, and to form an intermediate layer, a hard coating layer, and anti-fouling layer on the base film only through one coating process. CONSTITUTION: A UV curing hard coating composition includes 15-45 parts by weight of an uv curable resin, 0.01-3 parts by weight of a reactive fluorine compound, 5-35 parts by weight of inorganic nanoparticles having a surface which is processed with an acrylate compound, 1-5 parts by weight of a photopolymerization initiator, and a base film-soluble solvent based on 100.0 parts by weight of the total composition. A polarizing film includes the base film(120) which is attached to one side of a polarizer, an intermediate layer(130) which is formed on the base film, a hard coating layer(140) which is formed on the intermediate film, and an anti-flouring layer(150) which is formed on the hard coating layer.

Description

UV curable hard coating composition, polarizing plate and hard coating layer forming method having excellent pollution resistance using the same {UV CURING HARD COATING COMPOSITION

The present invention relates to a UV-curable hard coating composition and a hard coating layer forming method for producing a polarizing plate excellent in stain resistance, and more particularly, adhesion with a base film such as a triacetyl cellulose film (TAC film), transparency, UV-curable hard coating composition which is excellent in scratch resistance and stain resistance and can prevent rainbow phenomenon and has no damage to optical properties, physical properties and contamination resistance before and after treatment, even when triacetyl cellulose film is subjected to saponification treatment. It relates to a polarizing plate and a hard coating layer forming method used.

The polarizing film (Polarizing Film) is generally used in which a cellulose resin film is bonded to both sides of the polarizer on the film made of polyvinyl alcohol (PVA) or the like. Usually, one resin film (substrate film) has a protective film adhered for the purpose of preventing surface damage during transportation, and the other resin film has a multilayer structure in which an adhesive layer and a release film are laminated. Such a polarizing plate is used as a major component of a liquid crystal display (LCD).

In order to exhibit high reliability and durability in using the polarizing plate under various environments, firm adhesion between the polarizer and the base film is required. As a method of improving this adhesiveness, in the case of the triacetyl cellulose film used as a base film, the surface saponification process is performed previously with alkaline liquid, and it adheres to a polarizer using a polyvinyl alcohol-type adhesive etc.

Examples of the alkaline liquid used in the saponification treatment include aqueous solutions such as sodium hydroxide and potassium hydroxide, and alkaline aqueous solutions in which various organic solvents such as alcohol are added thereto. The conditions of the saponification treatment are not particularly limited, and it is preferable to use an aqueous solution having a concentration (normal concentration) of 0.1 to 10 N, and more preferably a concentration of 1 to 2 N. As for the temperature of alkaline aqueous solution, 0-100 degreeC is preferable, More preferably, 40-60 degreeC is preferable. The saponification time is 1 to 120 seconds, preferably about 10 to 40 seconds.

 However, since the saponification treatment uses a high concentration of alkaline liquid, the surface of the film is hydrophilized, so that the contact angle is greatly reduced, and when the surface treatment is performed with a hydrophobic resin, deterioration of adhesion force is caused.

If the surface treatment layer is subjected to functional coating such as hard coating or surface slipperiness before the saponification treatment, and the saponification treatment is carried out later, the surface treatment layer may be dissolved with alkali or the layer that realizes surface slipping may be broken. There is a problem that the effect is attenuated, such that surface hardness and scratch resistance are reduced.

Therefore, as a countermeasure to prevent this, the hardening layer is formed after the pretreatment of the TAC film in advance, or only the opposite side of the TAC film (adhesive side with the PVA film) on which the hard coating layer is formed, or the hard coating layer on the TAC film. After forming the method, a method of laminating a protective film on the coating surface and then saponification has been proposed.

However, such a countermeasure has a problem that the adhesion to the film is poor, a device suitable for designing a spherical structure is installed, or the process is increased, resulting in a problem in productivity and cost, which is not enough to be used yet. In addition, when the saponification process is performed after laminating the protective film, a protective film having an appropriate peeling force must be selected. Otherwise, both ends of the plywood are peeled off during saponification treatment, and the penetration of alkaline liquid during saponification treatment results. The lowering of the physical properties of both ends may occur.

On the other hand, in a film coated with a coating layer having a large difference in refractive index, it was often seen that an interface reflection and an interference fringe occurred at the interface of the mutually polymerized layer. In particular, when the refractive index of a light transmissive base material and the refractive index of a hard-coat layer differ, it is said that generation | occurrence | production of an interference fringe is easy to occur. In particular, when black is reproduced on the image display surface of the screen display device, an interference fringe is remarkably generated, and as a result, it is pointed out that the visibility of the image is lowered and the appearance of the image display surface is impaired.

In order to solve this problem, according to Japanese Patent Laid-Open No. 2003-131007 (published on May 08, 2003), in order to suppress the occurrence of interference fringes, the refractive index near the interface between the substrate and the hard coat layer is continuously changed. An optical film has been proposed.

In addition, it has been pointed out that the conventional image display surface is exposed to various usage environments, is easily scratched, and is easily attached dirt. In Japanese Patent Application Laid-Open No. 1998-104403 (published on April 24, 1998), in order to improve scratch resistance and contamination prevention of an image display surface, an optical laminated body in which a fouling-resistant additive (pollution agent) is added to a hard coat layer is provided. I'm proposing.

However, in the case of the product to which the general pollution-resistant agent is added, the pollution-resistant performance is extinguished with time and its effect is greatly reduced by periodic friction. Moreover, in the case of the surface treatment film used for the polarizing plate, the performance of this stain resistant agent is greatly weakened during the saponification process, and thus, the problem of loss of stain resistance after saponification treatment occurs.

Therefore, to compensate for the shortcomings of the above methods, an intermediate layer, a hard coating layer, and an antifouling layer are formed on the TAC film with one coating, so that the adhesion, transparency, scratch resistance, and stain resistance with the base film are excellent. The polarizing plate which can be prevented and which does not damage the optical characteristic, physical characteristic, and contamination resistance before and behind a process is calculated | required even if it applies the saponification process to a TAC film.

An object of the present invention is to provide an ultraviolet curable hard coating composition which is excellent in adhesiveness, transparency, scratch resistance and stain resistance with a triacetyl cellulose film (TAC film) and can prevent rainbow phenomenon.

Another object of the present invention is to provide a polarizing plate which is free from damage to optical properties, physical properties and contamination resistance before and after the saponification treatment, even after the saponification treatment is applied to the TAC film using the composition.

Still another object of the present invention is to provide a method for forming an intermediate layer, a hard coating layer and a stain resistant layer on a TAC film so as to suppress interference fringe generation.

UV-curable hard coating composition according to an embodiment of the present invention for achieving the above one object is 15 to 45 parts by weight of UV-curable resin, 0.01 to 3 parts by weight of reactive fluorine-based compound, acrylic based on 100 parts by weight of the total composition 5 to 35 parts by weight of inorganic nanoparticles surface-treated with a rate compound, 1 to 5 parts by weight of a photopolymerization initiator, and a residual amount of base film soluble solvent.

Polarizing plate according to an embodiment of the present invention for achieving the above another object is a base film adhered to one surface of the polarizer; An intermediate layer formed on the base film; A hard coating layer formed on the intermediate layer; And a fouling resistant layer formed on the hard coating layer, wherein the intermediate layer, the hard coating layer and the fouling resistant layer are formed from the UV curable hard coating composition.

Hard coating layer forming method according to an embodiment of the present invention for achieving the above another object is to (a) preparing a composition for UV-curable hard coating presented above; (b) applying the prepared composition on a base film; (c) drying the applied composition; And (d) irradiating ultraviolet light to cure the dried composition. Through the step (d) is formed an intermediate layer, a hard coating layer and a stain resistant layer on the base film.

UV-curable hard coating composition according to the present invention is excellent in adhesion, transparency, scratch resistance and stain resistance with the base film, can prevent the rainbow phenomenon, the intermediate layer on the base film, a hard coating layer, There is an advantage that can form a stain resistant layer. The ultraviolet curable hard coating composition according to the present invention has the effect of maintaining the visibility of the image and the appearance of the image display surface.

In addition, the polarizing plate produced by using the composition for hard coating according to the present invention, even if the triacetyl cellulose film is subjected to saponification treatment, there is no damage to optical properties, physical properties and pollution resistance before and after treatment, in particular scratch resistance and fouling resistance This can be used for the LCD of the mobile phone, navigation, note PC, etc. to be emphasized.

Hereinafter, a composition for forming a UV curable hard coating according to a preferred embodiment of the present invention, a method of forming a hard coating layer on the polarizing plate and the base film coated with the composition on the base film will be described in detail with reference to the accompanying drawings.

UV Curable Hard Coating Composition

UV-curable hard coating composition according to the present invention is based on 100 parts by weight of the total composition, 15 to 45 parts by weight of ultraviolet curable resin, 0.01 to 3 parts by weight of reactive fluorine-based compound, 5 to 35 weight of inorganic nanoparticles treated with acrylate compound Part, 1 to 5 parts by weight of the photopolymerization initiator and a residual amount of the base film soluble solvent may be included.

UV curable resin

Ultraviolet curable resins usable in the present invention include those having acrylate-based functional groups, for example, polyester resins of low molecular weight, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, And (meth) acrylate resins of polyfunctional compounds such as polybutadiene resin, polythiol polyene resin and polyhydric alcohol.

Specific examples thereof include ethylene glycol diacrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Polyol poly (meth) acrylates, di (meth) acrylates of bisphenol A-diglycidyl ether, polyesters obtained by esterifying polyhydric alcohols and polyhydric carboxylic acids and their anhydrides and acrylic acids Acrylate, polysiloxane polyacrylate, urethane (meth) acrylate, pentaerythritol tetra methacrylate, glycerin tri methacrylate, and the like, but are not limited thereto.

In addition, the ultraviolet curable resin which has an acrylate-type functional group may contain the acrylate compound containing a hydroxyl group.

An acrylate compound containing such a hydroxy group is an oligomer such as 2-hydroxyethyl acrylate oligomer, 2-hydroxypropyl acrylate oligomer, pentaerythritol triacrylate oligomer, 2-hydroxyethyl methacrylate, hydroxy Hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, kaduraacrylate, carduramethacrylate, caprolactone acrylate, caprolactone methacrylate Monomers such as 2,3-dihydroxypropylacryl, 2,3-dihydroxypropylmethacrylate, 4-hydroxymethylcyclohexylmethylacrylate, and 4-hydroxymethylcyclomethylmethacrylate Can be used.

Moreover, as ultraviolet curable resin which can be used by this invention, what contains fluorine, such as a fluorine-containing epoxy acrylate and a fluorine-containing alkoxysilane, can be used. Specific examples thereof include 2- (fefluorodecyl) ethyl methacrylate, 3-perfluorooctyl-2-hydroxy propyl acrylate, 3- (perfluoro-9-methyldecyl) -1, 2 -Epoxypropane, (meth) acrylic acid-2,2,2-trifluoroethyl, (meth) acrylic acid-2,2,2-trifluoromethyl, 3,3,3, -trifluoro propyl, and the like.

The ultraviolet curable resin of the present invention may be formed of any one of the above compounds, or may be formed by mixing two or more kinds.

The content of such ultraviolet curable resin is preferably included 15 to 45 parts by weight based on 100 parts by weight of the total composition. When the resin content is less than 15 parts by weight, the hardenability is lowered, the hardness of the hard coating layer is lowered, the scratch resistance is easily decreased, and when the resin content is more than 45 parts by weight, the viscosity of the final composition may be increased. This may be difficult to obtain or cause a change in optical properties.

Reactive fluorine compounds

In the present invention, a fluorine-based compound having a reactor of at least one functional group, preferably at least bifunctional group is used as the surfactant in order to improve the durability of the stain resistance and the scratch resistance, that is, to prevent the degradation of the physical properties after the saponification treatment. Such a reactive fluorine-based compound is formed as a fouling resistant layer on the hard coating layer. By using such a fluorine-based compound having a reactor, when the composition for a hard coat layer is cured, the fluorine-based compound is also copolymerized, and the fluorine-based compound is present in a bonded state rather than in an advantageous state in the hard coat layer.

As a result, even when the dirt on the surface of the hard coating layer is repeatedly washed, the fluorine-based compound can be semi-permanently maintained without peeling or missing, and the effect can be maintained even after saponification treatment. In addition, the hardness and the scratch resistance of the hard coat layer can be improved.

According to a preferred embodiment of the present invention, the reactive fluorine-based compound includes a monomer, oligomer, prepolymer or the like containing a bifunctional or higher polyfunctional acrylate group or methacrylate containing a fluorinated alkyl group or the like. Examples of the compound having a functional group capable of curing reaction include (meth) acrylate having an epoxy group, (meth) acrylate having a carboxyl group, (meth) acrylate having a hydroxy group, (meth) acrylate having an amino group, and sulfonic acid And (meth) acrylates having the same.

In addition, the reactive fluorine-based compound may have a more preferred form, which is composed of a fluorine-modified polyfunctional acrylate compound obtained by reacting a polyfunctional acrylate with a compound containing a perfluoro polyether. More specifically, perfluoro polyether polyol having a hydroxy group, a perfluoro polyether dibasic acid having a carboxylic acid, a perfluoro polyether epoxy compound having an epoxy group, and the like Examples thereof include monomers or oligomers having 2 to 16 functional groups formed by reacting a polyfunctional acrylate compound such as an ether compound and a modified acrylate compound having a carboxylic acid, an acrylate compound having an epoxy group, and an acrylate compound having an isocyanate group. do.

Such, fluorine-modified polyfunctional acrylate compound may be made to include a fluorine-containing compound represented by the following formula (1).

[Formula 1]

(Wherein Rf is a perfluoro group and R1 represents a hydrogen atom or a methyl group.)

At this time, Rf may have a molecular structure such as the following formula (2).

[Formula 2]

(Wherein, Rf1 is a straight chain perfluoro group having 1 to 10 carbon atoms, and Rf2, Rf3, Rf4 and Rf5 are straight chain perfluoro groups having 1 to 14 carbon atoms.)

The amount of the reactive fluorine compound added is 0.01 to 3 parts by weight based on 100 parts by weight of the total composition. When the content is less than 0.01 part by weight, scratch resistance may be insufficient, contamination resistance may be insufficient, and physical properties may be degraded after saponification treatment. If the content exceeds 3 parts by weight, it may be difficult to obtain a uniform surface during coating of the final composition, or may cause a change in optical properties.

Inorganic nanoparticles treated with acrylate compound

In the present invention, inorganic nanoparticles are used to increase scratch resistance and surface hardness. The inorganic nanoparticles of the present invention are surface-treated with an acrylate compound, and do not require a dispersing agent and a coupling agent to obtain uniform dispersibility between the binder and the inorganic material due to the uniform self-dispersion property. In addition, despite the use of inorganic particles, the use of uniform and small particles does not scatter the transmitted light, and has a stable dispersion characteristic, there is no entanglement between particles, resulting in high transparency and low turbidity.

In the inorganic nanoparticles, it is preferable to use 3 to 50% surface treated with an acrylate compound relative to the particle surface area. When using inorganic nanoparticles in the said range, it has uniform dispersibility and excellent transparency.

In addition, the average diameter of the inorganic nanoparticles is preferably 10 ~ 100nm. When the diameter of the inorganic nanoparticles is smaller than 10 nm, the surface strength and scratch resistance of the hard coating layer may be reduced, and when larger than 100 nm, the turbidity of the hard coating layer may be increased.

The inorganic nanoparticles usable in the present invention are not particularly limited, but one or two or more SiO ₂ , Al ₂ O ₃ , CaCO ₃ , TiO _2, and the like may be used.

The inorganic nanoparticles are preferably added in an amount of 5 to 35 parts by weight based on 100 parts by weight of the total composition. If the content of the inorganic nanoparticles is less than 5 parts by weight, the surface hardness and scratch resistance may be lowered, and if the content of the inorganic nanoparticles exceeds 35 parts by weight, the haze (turbidity) of the coating film of the particles may increase.

Photopolymerization initiator

As a photoinitiator which can be used by this invention, the well-known photoinitiator conventionally widely used can be used without limitation, For example, the benzophenone type compound, such as 1-hydroxy cyclohexyl phenyl ketone, can be used. More specifically, acetophenones, benzophenones, miclbenzoylbenzoate, α-amyl oxime ester, and thioxanthones may be used alone or in combination, but are not limited thereto.

In the present invention, the photopolymerization initiator is preferably added in an amount ratio of 1 to 5 parts by weight based on 100 parts by weight of the total composition. When the content of the photopolymerization initiator in the composition is less than 1 part by weight, a curing reaction may not occur or a long reaction time may be required, which may cause problems such as problems that cannot be applied to an actual process and insufficient hardness. When the content exceeds 5 parts by weight, the unreacted initiator may remain as an impurity to lower the hardness of the hard coat layer.

Base Film Soluble Solvent

The base film soluble solvent used in the present invention uses a solvent having solubility and swelling property in the base film. Specific examples of the soluble and swellable solvent include methyl ethyl ketone, cyclohexanone, acetone, diacetone alcohol, polyalcohol and ethers as methyl cellosolve, ethyl cellosolve, butyl cellosolve, cellosolve acetate, ester Methyl acetate, ethyl acetate, chloroform, methylene chloride, tetrachloroethane as a halogenated hydrocarbon, nitromethane, acetonitrile, N-methylpyrrolidone, N, N-dimethylformamide, others, dimethyl sulfoxide as a nitrogen-containing compound A seed can be mentioned, These solvent can be used 1 type or in mixture of 2 or more types.

There is no particular limitation on the amount of the solvent used, but in consideration of the viscosity of the composition, generally 40 to 70 parts by weight is suitable for 100 parts by weight of the total composition.

Such a base film soluble solvent has solubility and swelling property in the base film, and serves to form an intermediate layer between the hard coating layer and the base film when the hard coating layer is formed. The intermediate layer is in a chemical state in which the hard coating composition and the composition of the base film are mixed, and in an optical aspect, the intermediate layer exhibits an intermediate refractive index of the composition of the hard coating composition and the base film.

UV cure hard coating composition according to the present invention, in addition to the above components, if necessary, as an additive, a photosensitizer, a photosensitizer, a polymerization inhibitor, a leveling agent, a wettability improving agent, a surfactant, a plasticizer, an ultraviolet absorber, an antioxidant, an antistatic agent. , Silane coupling agent, inorganic filler, antifoaming agent and the like may be added one kind or two or more kinds. Since these additives are known to those skilled in the art and how to use them, the detailed description thereof will be omitted.

Polarizer

The UV-curable hard coating composition according to the present invention may be coated on a base film that serves to protect and support the polarizer in the polarizing plate.

Such a base film may be made of, for example, a cellulose ester resin, a polyester resin, a polycarbonate resin, a norbornene resin, a polyarylate resin, a polysulfone resin, or the like, and among these, particularly transparency and durability The triacetyl cellulose film (TAC film) of the acetyl cellulose-based resin or biaxially stretched polyester or norbornene-based resin can be used more suitably, and TAC film is particularly preferable. In addition, polycarbonate-based films excellent in durability and mechanical strength properties may also be preferably used.

When the base film is used in the polarizing plate, the polarizing plate may have a structure shown in FIG.

1 is a cross-sectional view schematically showing an embodiment of a polarizing plate according to the present invention.

Referring to Figure 1, the polarizing plate according to the present invention, the base film 120 is adhered to one surface of the polarizer 110, the surface of the adhered base film 120 from the UV-curable hard coating composition according to the present invention The intermediate layer 130, the hard coating layer 140, and the stain resistant layer 150 are formed.

In addition, the resin film 160 is adhered to the other surface of the polarizer 110, and the adhesive layer 170 and the release film 180 are formed on the resin film 160.

As the polarizer 110, a urea-based polarizer, a dichroic dye-based polarizer, etc., which are usually made of a film of polyvinyl alcohol-based resin, may be used, but are not limited thereto. The polarizer 110 may be cleaned and dried in advance to remove foreign substances. Preferably, the film of polyvinyl alcohol-based resin is continuously drawn to process the polarizer 110, and the obtained polarizer 110 and the base film 120 are bonded. Formation of the hard coating layer 140 may be coated after the polarizer 110 and the base film 120 after the coating on the base film 120 in advance, or after the polarizer 110 and the base film 120 are bonded. have.

The thickness of the hard coating layer 140 applied to the base film 120 is preferably 2 ~ 20㎛. If the hard coating layer 140 is less than 2㎛ hard to implement high hardness and scratch resistance, it is easy to generate a rainbow, if it exceeds 20㎛ is not economical, and may cause curl of the film (curl).

Hard coating layer formation method

Figure 2 is a flow chart schematically showing an embodiment of a method for forming a hard coating layer on a base film according to the present invention.

2, the hard coating layer forming method according to the present invention comprises a composition for preparing a hard coating step (S210), a composition applying step (S220), a drying step (S230) and an ultraviolet curing step (S240).

In the manufacturing step for the hard coating composition (S210) to prepare a composition for ultraviolet curing hard coating according to the present invention.

In the composition applying step (S220), the prepared UV curable hard coating composition is applied onto the base film. As a method of coating the composition on the base film, a technique such as a bar coating method, a knife coating method, a gravure coating method, a micro gravure coating method, a slot die coating method, or the like may be used.

In the drying step (S230) to remove the solvent by drying the applied composition.

In the ultraviolet curing step (S240) to form a hard coating layer on the base film by curing the dried composition by irradiation with ultraviolet light. Ultraviolet lamps that can be used include high pressure mercury lamps, metal halide lamps, xenon lamps, microwave electrodeless lamps and the like. The general wavelength range required for the curing of the ultraviolet curable composition is about 200 to 400nm, the light amount may be 100 ~ 1,000mJ / ㎡.

Figure 3 is a transmission electron micrograph of the cross section of the TAC film with a hard coating layer according to the present invention. In FIG. 3, reference numeral 310 denotes an epoxy resin used to support a TAC film.

Referring to Figure 3, through the hard coating layer forming method (S210 ~ S240), that is, the intermediate layer 130, the hard coating layer 140 and the pollution-resistant layer 150 is formed on the TAC film 120 by only one coating. It can be confirmed. Here, the two relatively thin layers, that is, the intermediate layer 130 formed between the base film 120 and the hard coating layer 140 and the pollution-resistant layer 150 formed on the surface of the hard coating layer 140, as described above, It is formed from a base film soluble solvent and a reactive fluorine compound, respectively.

Example

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. However, this is presented as a preferred example of the present invention and in no sense can be construed as limiting the present invention.

Details that are not described herein will be omitted because those skilled in the art can sufficiently infer technically.

Example 1

Formation of Hard Coating Layer

Urethane acrylate oligomer (SU520: manufactured by Iso Chemical Co., Ltd., 10 functional) 29.3g as ultraviolet curable resin, dipentaerythritol hexa acrylate (DPHA, SK CYTEC Co., Ltd. manufactured, 6 functional) 11.7g, reactive fluorine-based interface 0.6 g of active agent (RS-503, manufactured by DIC), 20.4 g of methyl acetate and 20.4 g of butyl acetate were sequentially mixed, stirred for 10 minutes, and then dispersed therein with SiO ₂ particles whose surface was treated with 5% acrylate. 17.6 g of the sol (C 784, manufactured by Nano Resin, average diameter: 20 nm, 50 wt% solids) was added thereto, and the mixture was stirred and dispersed for 10 minutes. Thereafter, 2.5 g of Igacure 184 (Shibagaiki Co., Ltd.) was added to the dispersion as a photopolymerization initiator, followed by stirring for 30 minutes to prepare a final hard coating solution.

The composition was coated on a TAC film (thickness 40 μm, manufactured by Konica) using a # 16 bar coater, and dried at 80 ° C. for 2 minutes. After drying, UV irradiation was performed at a light quantity of 200 mJ with a high-pressure mercury lamp to cure.

Pencil hardness, scratch resistance, haze and transmittance of the TAC film having the hard coating layer formed by the above process was measured according to JIS standard, and the evaluation of contamination resistance such as water contact angle, oleic acid contact angle, oil pen test, durability curling And rainbow. The results are shown in Table 1.

In addition, after the film was saponified for 15 seconds in an 18wt% NaOH aqueous solution at a temperature of 50 ° C. and sufficiently dried, a polarizing plate was prepared using the film, and after being coated with an adhesive (PSA), it was attached to a bare glass for LCD. After that, the evaluation items were evaluated again. The results are shown in Table 2.

Property evaluation

(1) Pencil hardness: Using a Mitsubishi evaluation pencil (UNI) with a pencil hardness tester (Shinto Scientific, Heidon) to draw 5kg 5 times at 500kg / cm ² load, 0.5mm / sec speed 5 times, the number of wounds It was confirmed.

(2) Scratch resistance: The steel wool (# 0000) was used to check the number of scratches after rubbing 1000g load, 50mm / sec speed, 100mm in 10 round trips.

<Evaluation Criteria>

Pass: No scratches.

NG: More than 1mm scratches occur

(3) Haze and permeability measurement: It measured using NHD-2000 (Nippon Denshoku Kogyo Co.).

(4) Contact angle: With respect to the surface of the hard coat layer, the contact angles of water and oleic acid were measured using Phoenix 300 (SEO).

(5) Pollution resistance evaluation: The visual inspection level of the oil coating pen (Monomi blue color name pen) on or off the surface of the hard coating layer was evaluated.

evaluation writing Clear One Not well used Cleared well 2 Increasingly used Only part of it 3 Written Not half removed 4  Well written Not erased

      (6) Durability: The microfiber cloth (Woojin ACT, WW-4009) was rubbed with 1000g load, 50mm / sec speed, 100mm in 1,000 round trips, and then stain resistance was evaluated.

(7) Curing: A film sample of 100 mm x 100 mm size was prepared, and the height of the highest of the four corners at the bottom was measured.

(8) Rainbow (interference pattern) test

In order to prevent back reflection, black tape was stuck to the opposite side of the hard coating layer, and visual inspection was performed under the three wavelength fluorescence on the surface of the hard coating layer, and then evaluated by the following evaluation criteria.

<Rainbow evaluation criteria>

 1: No rainbow in all directions.

 2: weakly occur

 3: occurs strongly

Example 2

The same procedure as in Example 1 was carried out except that 20.4 g of methyl ethyl ketone was mixed instead of 20.4 g of methyl acetate.

Comparative Example 1

The same procedure as in Example 1 was carried out except that 20.4 g of methyl acetate was used instead of 20.4 g of methyl acetate.

Comparative Example 2

The same procedure was followed as in Example 1 except that 0.6 g of BYK 333 (polyether modified dimethylpolysiloxane, manufactured by BYK Chemie) was mixed instead of 0.6 g of a reactive fluorine-based surfactant (RS-503, manufactured by DIC).

Comparative Example 3

Except for the reactive fluorine-based surfactant (RS-503, manufactured by DIC) in Example 1, UV curable reactive silicone additive Tego Rad2300 (polyether modified dimethylpolysiloxane, manufactured by Degussa) was carried out in the same manner.

TABLE 1

TABLE 2

As can be seen in Tables 1 and 2, the compositions of Examples 1 to 2 of the present invention are excellent in hardness and stain resistance compared to Comparative Examples 1, 2 and 3 which do not contain a reactive fluorine-based compound and a base film soluble solvent. Able to know.

Although preferred embodiments have been described above, various modifications and variations can be made without departing from the spirit and scope of the invention, and the appended claims include such modifications and variations that fall within the spirit of the invention.

1 is a cross-sectional view schematically showing an embodiment of a polarizing plate according to the present invention.

Figure 2 is a flow chart schematically showing an embodiment of a method for forming a hard coating layer on a base film according to the present invention.

Figure 3 is a transmission electron micrograph of the cross section of the TAC film with a hard coating layer according to the present invention.

Claims (22)

15 to 45 parts by weight of an ultraviolet curable resin, 0.01 to 3 parts by weight of a reactive fluorine compound, 5 to 35 parts by weight of inorganic nanoparticles surface-treated with an acrylate compound, 1 to 5 parts by weight of a photopolymerization initiator, and 100 parts by weight of the total composition, and UV-curable hard coating composition comprising a residual amount of the base film soluble solvent. The method of claim 1, wherein the ultraviolet curable resin UV-curable hard coating composition characterized by having an acrylate-based functional group. The method of claim 2, wherein the ultraviolet curable resin A hydroxy group-containing acrylate compound is contained, UV curable composition for hard coating. The hydroxy group-containing acrylate compound is according to claim 3 Oligomers of materials selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and pentaerythritol triacrylate; and 2-hydroxyethyl methacrylate, hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, kaduraacrylate, carduramethacrylate, Caprolactone acrylate, caprolactone methacrylate, 2,3-dihydroxypropyl acrylate, 2,3-dihydroxypropyl methacrylate, 4-hydroxymethylcyclohexylmethyl acrylate, and 4-hydroxy UV-curable hard coating composition, characterized in that at least one of the monomers of the material selected from the group consisting of methyl cyclomethyl methacrylate. The method of claim 1, wherein the ultraviolet curable resin UV-curable hard coating composition comprising a fluorine. The method of claim 1, wherein the reactive fluorine-based compound It is a fluorine-modified polyfunctional acrylate compound formed by reacting a polyfunctional acrylate with the compound containing a perfluoro polyether, The composition for ultraviolet curable hard coatings characterized by the above-mentioned. The method of claim 1, wherein the inorganic nanoparticles UV-curable hard coating composition, characterized in that the surface treatment 3 to 50% by surface area acrylate compound. The method of claim 1, wherein the inorganic nanoparticles UV-curable hard coating composition, characterized in that the average diameter is 10 ~ 100nm. The method of claim 1, wherein the inorganic nanoparticles An ultraviolet curable hard coating composition comprising one or more materials selected from the group consisting of SiO ₂ , Al ₂ O ₃ , CaCO ₃ , and TiO ₂ . The method of claim 1, wherein the photopolymerization initiator UV-curable hard coating composition, characterized in that at least one member selected from the group consisting of acetophenones, benzophenones, micro benzoyl benzoate, α- amyl oxime ester, and thioxanthones. The method of claim 1, wherein the base film soluble solvent is Methyl ethyl ketone, cyclohexanone, acetone, diacetone alcohol, polyhydric alcohol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, cellosolve acetate, methyl esters, ethyl acetate, chloroform, methylene chloride, For UV-curable hard coating, characterized in that it consists of one material or a mixture thereof in the group consisting of tetrachloroethane, nitromethane, acetonitrile, N-methylpyrrolidone, N, N-dimethylformamide, dimethyl sulfoxide Composition. The method of claim 1, wherein the composition Further comprising at least one selected from the group consisting of a photosensitizer, a photosensitizer, a polymerization inhibitor, a leveling agent, a wettability improving agent, a surfactant, a plasticizer, an ultraviolet absorber, an antioxidant, an antistatic agent, a silane coupling agent, an inorganic filler, and an antifoaming agent. UV-curable hard coating composition, characterized in that. A base film adhered to one surface of the polarizer; An intermediate layer formed on the base film; A hard coating layer formed on the intermediate layer; And It includes a fouling resistant layer formed on the hard coating layer, The intermediate layer, the hard coating layer and the stain resistant layer A polarizing plate formed from the composition of any one of claims 1 to 12. The method of claim 13, wherein the hard coating layer Thickness is 2-20 micrometers, The polarizing plate characterized by the above-mentioned. The method of claim 13, wherein the intermediate layer The polarizing plate having an intermediate refractive index of the base film and the hard coating layer. The method of claim 13, wherein the polarizer It is a urea type polarizer or a dichroic dye type polarizer which consists of a film of polyvinyl alcohol-type resin, The polarizing plate characterized by the above-mentioned. The method of claim 13, wherein the base film A polarizing plate selected from the group consisting of cellulose ester resins, polyester resins, polycarbonate resins, norbornene resins, polyarylate resins, and polysulfone resins. In the method of forming a hard coating layer on the base film, (a) preparing a composition of any one of claims 1 to 12; (b) applying the prepared composition on a base film; (c) drying the applied composition; And (d) hardening the dried composition by irradiating ultraviolet rays to form a hard coating layer. 19. The method of claim 18, wherein step (b) A hard coating layer forming method comprising any one of a bar coating method, a knife coating method, a gravure coating method, a micro gravure coating method and a slot die coating method. 19. The method of claim 18, wherein the step (d) And an intermediate layer having an intermediate refractive index between the base film and the hard coating layer is formed between the base film and the hard coating layer from the base film soluble solvent. 19. The method of claim 18, wherein the step (d) Hard coating layer forming method characterized in that the fouling-resistant layer is formed on the hard coating layer from a reactive fluorine-based compound. 19. The method of claim 18, wherein step (d) A method of forming a hard coating layer using any one of a high pressure mercury lamp, a metal halide lamp, a xenon lamp, and a microwave electrodeless lamp.

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