KR20190085353A - Method for preparing of polarizer protecting film - Google Patents

Abstract

The present invention relates to a method for manufacturing a polarizer protective film which can obtain a polarizer protective film excellent in scratch resistance and hardness, by comprising the steps of: applying a coating composition comprising a siloxane compound including an alicyclic epoxy group on at least one surface of a base film; and stretching and thermosetting the base film to which the coating composition is applied; or performing photocuring on the coating composition after stretching the base film to which the coating composition is applied.

Description

TECHNICAL FIELD [0001] The present invention relates to a polarizer protective film,

The present invention relates to a method for producing a polarizer protective film, and is for producing a polarizer protective film which can exhibit excellent physical and optical characteristics and can prevent damage to the lower polarizer.

BACKGROUND ART [0002] Liquid crystal display devices are widely used from cellular phones and portable electronic devices to personal computers and large-sized electronic devices such as televisions, and their use is one of the ever-expanding flat panel displays. Since such a liquid crystal display device is not a self-luminous type device, a light source such as a backlight unit is usually placed on the back of a lower polarizer plate provided on the lower side of the liquid crystal cell, and the light emitted from the light source is transmitted through the liquid crystal cell, So that an image is displayed.

In recent years, a large load has been applied to the central portion of the liquid crystal cell, and a sagging phenomenon of the lower polarizer is generated. Thus, the polarizer protective film of the lower polarizer attached to the liquid crystal cell And the lower polarizing plate is caught by the diffusion sheet on the surface of the backlight unit. To solve this problem, a method of coating a hard coating layer on a protective film of a lower polarizer plate has been proposed, but there is a problem of an increase in process cost.

In accordance with this necessity, development of a polarizer protective film which can reduce the cost of the process, and which can prevent damage to the lower polarizer while maintaining price competitiveness is required.

Korean Laid-Open Publication No. 2012-0107256

The present invention provides a polarizer protective film having a thin and scratch resistance and a method for producing a polarizer protective film having excellent physical and optical properties, which is intended to solve the damage of the polarizer protective film of the lower polarizer plate .

In order to solve the above-mentioned problems, the present invention provides a method for manufacturing a semiconductor device, comprising: coating a coating composition comprising a siloxane-based compound on at least one surface of a base film; And

Stretching and thermosetting the substrate film coated with the coating composition; Or after stretching the base film coated with the coating composition, performing photo-curing on the coating composition.

By applying the coating composition on the substrate of the present invention and stretching it together with the substrate, a polarizer protective film having little shrinkage upon curing and excellent adhesion to a substrate can be produced. Further, the polarizer protective film of the present invention has excellent scratch resistance and hardness.

In addition, due to deflection of the lower polarizer plate, the polarizer protective film is damaged by abutting against the diffusion sheet on the surface of the backlight unit, thereby preventing defects in the apparatus, thereby exhibiting excellent optical properties.

1 is a view illustrating a polarizer protective film manufactured according to an embodiment of the present invention.
2 and 3 are views showing a polarizer including a polarizer protective film manufactured according to an embodiment of the present invention.
4 is a view illustrating a liquid crystal display including a polarizer protective film manufactured according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to explain the present invention in more detail to those skilled in the art.

The present invention relates to a method of manufacturing a polarizer protective film adjacent to a backlight unit of a lower polarizer plate provided in a lower layer portion of a liquid crystal cell in a liquid crystal display device and comprises applying a coating composition containing a siloxane compound on at least one surface of a base film , A polarizer protective film excellent in adhesion and surface hardness to the base material and excellent in scratch resistance can be obtained by stretching and thermosetting the base film coated with the coating composition or performing photo-curing of the coating composition after stretching have.

In addition, the polarizer protective film of the present invention can prevent damage that may occur due to deflection of the lower polarizer.

FIG. 4 shows an embodiment of a liquid crystal display including a polarizer protective film manufactured according to an embodiment of the present invention. The liquid crystal display device shown in Fig. 4 includes a liquid crystal cell 20; An upper polarizer plate 10 provided on an upper portion of the liquid crystal cell 20; A lower polarizer plate 30 provided on a lower portion of the liquid crystal cell 20; And a backlight unit 40 provided on a lower portion of the lower polarizer plate. The polarizer protection film 34 is provided on the lower polarizer plate 30 adjacent to the backlight unit.

In the present invention, the terms 'upper surface' and 'upper' mean a surface or a direction arranged toward a viewer side, that is, a viewer side when a polarizing plate is mounted on a device such as a liquid crystal display device. Conversely, 'under' and 'under' mean the face or direction opposite the viewer, that is, facing the backlight unit when the polarizer is mounted on the device.

Hereinafter, the method for producing the polarizer protective film of the present invention will be described in more detail.

According to one embodiment of the present invention, there is provided a method for manufacturing a semiconductor device, comprising: applying a coating composition comprising a siloxane-based compound on at least one surface of a base film; And stretching and thermosetting the base film to which the coating composition is applied; Or after stretching the base film coated with the coating composition, performing photo-curing on the coating composition.

According to an embodiment of the present invention, the siloxane-based compound may be polymerized by reaction of two or more siloxane-based compounds with a solvent such as a sol-gel polymerization, and at least one of the two or more siloxane-based compounds includes an alicyclic epoxy group Siloxane-based compound. In the siloxane-based compound polymerization process, the weight ratio (compound containing no alicyclic epoxy group) of the compound containing and not containing the alicyclic epoxy group may be 1: 2 to 5: 1, The weight ratio according to another example may be 1: 2 to 2: 1.

According to another embodiment of the present invention, the siloxane-based compound may be represented by the following general formula (1).

[Chemical Formula 1]

In Formula 1,

R ₁ is a linear or branched alkyl group containing an alicyclic epoxy group,

R ₂ and R ₃ are the same or different and each independently represent a hydroxyl group (-OH); Or an alkoxy group having 1 to 5 carbon atoms,

R ₄ is a substituted or unsubstituted straight or branched alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a straight or branched alkyl group containing a glycidyl ether group,

m and n are each an integer of 1 to 20, and when n is 2 or more, the structures in parentheses are the same or different from each other.

The polarizer protective film of the present invention is used for protecting the polarizer from the outside, and at least one surface of the polarizer .

On the other hand, as the liquid crystal display device becomes larger and slimmer, a sagging phenomenon of the lower polarizer plate occurs, and the lower protective film of the lower polarizer plate comes into contact with the backlight unit, causing scratches.

Therefore, the polarizer protective film produced according to one embodiment of the present invention exhibits excellent physical properties such as scratch resistance and hardness due to the coating layer, thereby effectively protecting the lower polarizer, and being applicable to a polarizer for a liquid crystal display device .

A polarizer protective film produced according to an embodiment of the present invention includes a base film; And a coating layer formed on one surface of the base film.

The base film is not particularly limited, but may be a polyester, a polyethylene, a cyclic olefin polymer (COP), a cyclic olefin copolymer (COC), a polyacrylate , PAC), polycarbonate (PC), polymethylmethacrylate (PMMA), polyimide (PI), or cellulose.

The thickness of the base film is not particularly limited, but a film having a thickness of about 50 to 1,000 占 퐉, specifically 100 to 500 占 퐉 may be used.

The method for forming the base film is not particularly limited, and an unstretched base film can be prepared by a suitable film forming method such as a solution casting method, a melt extrusion method, a calendering method, and a compression molding method.

When the base film is stretched, if the polymer is rearranged in the stretching process and a functional coating layer or the like is further formed on the stretched base film, there is a problem that the adhesion is reduced. Therefore, in order to secure the adhesion, a separate process such as forming a primer layer or adding a functional compound capable of enhancing adhesion to the coating layer has been proposed. In the former case, a separate process is added in the manufacturing process There is a problem that productivity is lowered, and physical and chemical properties are different for each film, so that development of general purpose primers is difficult. Further, adding a functional compound to the coating layer may also cause a problem of cost increase and other property deterioration.

According to an embodiment of the present invention, there is provided a polarizer protective film which has high adhesion to a film to be a base film without sufficient additional primer layer, has sufficient scratch resistance, Lt; / RTI > films.

According to an embodiment of the present invention, the base film can be coated on one side thereof in an unstretched state.

In another embodiment, the substrate film may be subjected to uniaxial stretching prior to application of the coating composition.

At this time, the stretching direction is not particularly limited, and it may be stretched in the width direction (TD) direction or the length (MD) direction, and may be uniaxially stretched or biaxially stretched. The stretching ratio can be stretched so as to be 1.1 times or more, 1.2 times or 1.5 times or more, 5 times or less, or 3 times or less based on the length in the stretching direction.

A coating composition comprising a siloxane-based compound containing the unit represented by the formula (1) is applied on at least one surface of the unstretched or uniaxially stretched substrate film.

Generally, in order to form a functional coating layer such as a hard coating layer on a polarizer protective film, a method of applying a coating composition on a stretched film, and drying and curing it is used. However, in the case of the stretched film, since the polymer is rearranged in the stretching process, there is a problem that the coating layer does not adhere well to the stretched film. There is a method of forming a primer layer in order to ensure adhesion, however, there is a problem that productivity is lowered due to the addition of a separate step in the manufacturing process, and there is a problem that development of a general purpose primer is difficult.

According to the manufacturing method of the present invention, the coating composition applied on the base film is thermally cured at the same time as the drawing, or is stretched and photocured, whereby adhesion to the stretched base film can be achieved without requiring a separate primer layer It is possible to provide a polarizer protective film which is high in thickness and can be thinned.

On the other hand, when the coating composition is too rigid, there is a problem that the coating layer becomes uneven or the drawing is not performed properly in the drawing process after coating. On the contrary, when the coating composition is too soft, Sufficient strength and scratch resistance may not be secured after curing.

Therefore, in order to exhibit sufficient scratch resistance after a uniform stretching process and curing, it is important to appropriately adjust the flexibility and strength of the coating composition in addition to the control of the draw ratio of the base film.

Thus, according to the production method of the present invention, it is possible to provide a polarizer protective film satisfying the above-mentioned requirements by optimizing the composition of the coating composition and the stretching process.

Conventionally, a radical-curable binder such as an acrylate-based binder is mainly used for forming a coating layer of a polarizer protective film. However, since the radical hardening type resin is used for the purpose of forming a coating layer having a high hardness with a high degree of curing, the crosslinking distance is short and hardening shrinkage phenomenon occurs, thereby causing deterioration of adhesion to the base film or curling or cracking It is likely to occur.

However, according to the present invention, a coating composition comprising a siloxane-based compound containing a unit represented by the above-mentioned formula (1) having little curing shrinkage is used without using a radical curing binder having a large hardening shrinkage such as an acrylate binder By performing the stretching, thermosetting or stretching after the application of such a coating composition, it is possible to remarkably reduce the adhesiveness to the base film due to the hardening shrinkage and the curling and cracking of the coating layer. Therefore, a protective film having high adhesion between the coating layer and the base film and satisfying flexibility and hardness at the same time can be produced.

The coating composition coated on the base film includes a siloxane-based compound containing a unit represented by the formula (1). The siloxane-based compound containing the unit represented by the formula (1) can be polymerized by a reaction such as sol-gel polymerization with two or more siloxane-based compounds.

In one embodiment of the present invention, R ₁ is a linear or branched alkyl group containing an alicyclic epoxy group, and the alkyl group may have 1 to 10 carbon atoms.

In another embodiment, the alicyclic epoxy group of R < ₁ > is a cycloalkyl group having 3 to 6 carbon atoms and having an epoxy group. Specifically, the alicyclic epoxy group may be a 3,4-epoxycyclohexyl group.

The R ₁ may be a 3,4-epoxycyclohexylethyl group.

In one embodiment of the present invention, R ₂ and R ₃ are the same or different from each other, and each independently represents a hydroxyl group (-OH); Or an alkoxy group having 1 to 5 carbon atoms.

According to another embodiment, R ₂ and R ₃ are the same or different and are each independently a hydroxyl group (-OH), a methoxy group, an ethoxy group or a propoxy group.

According to another embodiment, R ₄ is a substituted or unsubstituted, linear or branched alkyl group having 1 to 10 carbon atoms; A substituted or unsubstituted C3 to C30 cycloalkyl group; A substituted or unsubstituted alkoxy group having 1 to 10 carbon atoms; A substituted or unsubstituted C6 to C30 aryl; Or a linear or branched alkyl group having 1 to 10 carbon atoms including a glycidyl ether group.

In another embodiment, R ₄ is a substituted or unsubstituted methyl group; A substituted or unsubstituted ethyl group; A substituted or unsubstituted propyl group; A substituted or unsubstituted butyl group; A substituted or unsubstituted cyclopropyl group; A substituted or unsubstituted cyclobutyl group; A substituted or unsubstituted methoxy group; A substituted or unsubstituted ethoxy group; A substituted or unsubstituted propoxy group; A substituted or unsubstituted phenyl group; A substituted or unsubstituted biphenyl group; A substituted or unsubstituted naphthyl group; A methyl group including a glycidyl ether group; An ethyl group containing a glycidyl ether group; A propyl group containing a glycidyl ether group; Or a butyl group containing a glycidyl ether group.

According to one embodiment of the present invention, the formula (1) may be represented by the following formula (1-1) or (1-2).

[Formula 1-1]

[Formula 1-2]

In the above formulas 1-1 and 1-2,

R ₁ to R ₃ have the same definitions as in the above formula (1)

R ₃₁ and R ₃₂ are the same or different from each other, and each independently represents a hydroxyl group (-OH); Or an alkoxy group having 1 to 5 carbon atoms,

R ₄₁ is a substituted or unsubstituted straight or branched alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a straight or branched alkyl group containing a glycidyl ether group,

m1, m2 and n1 are each an integer of 1 to 20,

n2 and n3 are integers of 1 to 20, respectively, and 2? n2 + n3? 20.

The description of R ₃ described above is applied to R ₃₁ and R _32, and the description of R ₄ described above is applied to R ₄₁ .

The terminal group of the unit represented by the formula (1) may be hydrogen, a hydroxyl group (-OH) or a substituted or unsubstituted alkyl group, and specifically includes hydrogen, a hydroxyl group (-OH) .

According to an embodiment of the present invention, the formula 1 may be represented by the following formula 1-3.

[Formula 1-3]

In Formula 1-3,

R ₁ to R ₄ have the same definitions as in the above formula (1)

p is the mole fraction, 0 < p < 1,

q is a mole fraction, 0 < q < 1,

p + q is 1,

s is an integer of 1 to 20;

In one embodiment of the present invention, the formula 1-3 is a random copolymer, and the molar ratio (p: q) of the unit including the alicyclic epoxy group to the unit not including the alicyclic epoxy group may be 1: 2 to 5: 1 .

The siloxane-based compound has a weight average molecular weight of 500 to 5,000 g / mol. If the weight-average molecular weight of the siloxane-based compound is too large, the coating property may not be good due to the high viscosity, and the coating film may be cracked in the drawing process due to poor stretchability. If the weight average molecular weight is too small, have.

The coating composition contains 50 to 99.95% by weight of a siloxane-based compound containing the unit represented by the formula (1). According to an example, the coating composition may include 60 to 99.95 wt% of a siloxane-based compound containing a unit represented by the formula (1). According to another example, the coating composition may contain 70% by weight to 99.95% by weight or 90% by weight to 99.5% by weight of the siloxane-based compound containing the unit represented by the formula (1). When the content of the siloxane-based compound satisfies the above range, there is an advantage that the hardness of the coating film is excellent.

The coating composition may further include a cationic photoinitiator or a cationic thermal initiator. The coating composition may contain 50 to 99.95 wt% of a siloxane-based compound containing the unit represented by the formula (1), a cationic photoinitiator, And 0.05% by weight to 10% by weight of a cationic thermal initiator.

The coating composition may further comprise a curing resin in addition to the siloxane-based compound containing the unit represented by the above-mentioned formula (1), wherein the curing resin includes an epoxy compound, an acrylate compound or a mixture thereof.

The curable resin may be contained in an amount of 100 parts by weight or less, or 0.1 parts by weight or more and 70 parts by weight or less, based on 100 parts by weight of the siloxane-based compound containing the unit represented by the formula (1). When the content of the curing resin satisfies the above range, there is an advantage that adhesion with the base film, coatability, stretchability and mechanical properties of the coating film are improved.

According to one embodiment of the present invention, the weight average molecular weight of the epoxy compound is not particularly limited, but may be about 100 to 5,000 g / mol, or about 200 to 5,000 g / mol. If the weight average molecular weight of the epoxy compound is too large, the viscosity may be high and the coating property may be poor. If the weight average molecular weight is too small, the hardness is low.

The epoxy-based compound contains at least one epoxy group and is cured by cations generated from a cationic thermal initiator by heat treatment. The binder is an aromatic epoxy compound, a hydrogenated epoxy compound, an alicyclic epoxy compound, an aliphatic Epoxy compounds, and the like, and alicyclic epoxy compounds can be preferably used.

The aromatic epoxy compound refers to an epoxy compound containing at least one aromatic hydrocarbon ring in the molecule and includes, for example, diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F , Bisphenol-type epoxy resins such as diglycidyl ether of bisphenol S; Phenol novolak epoxy resin, cresol novolak epoxy resin, and hydroxybenzaldehyde phenol novolak epoxy resin, glycidyl ether of tetrahydroxyphenylmethane, glycidyl ether of tetrahydroxybenzophenone, epoxy And polyvinylphenol, and the like.

The hydrogenated epoxy compound refers to an epoxy compound obtained by selectively hydrogenating the aromatic epoxy compound under a pressure in the presence of a catalyst, but is not limited thereto. Of these, the hydrogenated bisphenol A It is preferable to use diglycidyl ether.

The alicyclic epoxy compound means an epoxy compound in which an epoxy group is formed between adjacent two carbon atoms constituting an aliphatic hydrocarbon ring, but is not limited thereto. For example, 2- (3, Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4,5- Epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, vinylcyclohexanedioxide, bis (3,4-epoxycyclohexylmethyl) adipate, bis Epoxycyclohexylmethyl) adipate, exo-exobis (2,3-epoxycyclopentyl) ether, endo-exobis (2,3-epoxycyclopentyl) ether, 2,2-bis [4 - (2,3-epoxypropoxy) cyclohexyl] propane, 2,6-bis (2,3-epoxypropoxycyclohexyl-p-dioxane), 2,6- Bis (3,4-epoxycyclohexyl) propane, dicyclopentadienedioxide, 1,2-epoxy-6- (2,3-epoxypropoxy) (2,3-epoxy) cyclopentylphenyl-2,3-epoxypropyl ether, 1- (2,3-epoxypropoxy) phenyl-5,6- (2,3-epoxy) cyclopentylphenyl-2,3-epoxypropyl ether), 1,2-bis [5- (1,2-epoxy) -4 Ethanocyclopentenyl phenyl glycidyl ether, methylene bis (3,4-epoxycyclohexane) ethylene glycol di (3,4-epoxycyclohexylmethyl) ether, ethylene bis (3, Epoxycyclohexanecarboxylate), ε-caprolactone (1 to 10 mol) adduct of 3,4-epoxycyclohexanemethanol and poly (3 to 20) alcohol (GR, TMP, PE, DPE, Hexapentaerythritol), and the like. Among them, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate is particularly preferably used from the viewpoint of reactivity.

According to one embodiment of the present invention, the weight average molecular weight of the acrylate compound may be about 100 to 5,000 g / mol, or about 200 to 5,000 g / mol. If the weight average molecular weight of the epoxy compound is too large, the viscosity may be high and the coating property may be poor. If the weight average molecular weight is too small, the hardness is low.

The acrylate compound may be an alkyl (meth) acrylate including an alkyl (meth) acrylate, an alkyl acrylate, an epoxy (meth) acrylate, a hydroxyalkyl acrylate and a carboxyl group, an acrylate including a sulfonate, But is not limited thereto.

In one embodiment of the present invention, the coating composition further comprises a silicon-based or fluorine-based compound. By further including a silicone-based or fluorine-based compound, the anti-blocking property and slipperiness of the protective film are advantageously improved.

Examples of the silicon-based compound include a non-reactive silicone compound having a silicon group such as dimethylsiloxane and methylsiloxane and containing an alkyl group, a polyether group or the like; Or a reactive silicone compound having a silicon group and containing a vinyl group, a (meth) acrylate group, or a (meth) acryloxy group; (Meth) acrylate group, a (meth) acryloxy group, and the like. The reactive silicone compound having a silicon group and containing a vinyl group, a (meth) acrylate group, Can be used.

Examples of the fluorine compound include a non-reactive fluorine compound having a fluorine group such as a fluoroalkyl group; Or a reactive fluorine compound having a fluorine group and containing a vinyl group, a (meth) acrylate group, or a (meth) acryloxy group; A resin having a fluorine group, an oil or a surfactant, but the present invention is not limited thereto.

According to an embodiment of the present invention, the silicon-based or fluorine-based compound may be added to the coating composition in an amount of about 0.1 part by weight or more, or about 0.2 part by weight per 100 parts by weight of the siloxane-based compound containing the unit represented by the formula Or about 0.3 parts by weight or more, about 10 parts by weight or less, about 5 parts by weight or less, or about 2 parts by weight or less. If the content of the silicon-based or fluorine-based compound is too small, the anti-blocking property and the slipping property improving effect may be low. If the content is too high, the hardness of the coating film may decrease or the appearance of the coating may deteriorate.

According to one embodiment of the present invention, the coating composition comprises a cationic photoinitiator or a cationic thermal initiator.

The cationic photoinitiator is a compound that produces a cationic species or Lewis acid by irradiation with active energy rays such as ultraviolet rays, and means a compound that acts on a cationic polymerizable group such as an epoxy group to initiate cationic polymerization reaction.

As the cationic photoinitiator, cationic photoinitiators commonly used in the art can be used without limitation. For example, the cationic photoinitiator may preferably include a sulfonium salt or an iodonium salt.

Specific examples of the cationic polymerization initiator including a sulfonium salt or an iodonium salt include diphenyl (4-phenylthio) phenylsulfonium hexafluoroantimonate (Diphenyl (4- phenylthio) phenylsulfonium hexafluoroantimonate), diphenyl (4-phenylthio) phenylsulfonium hexafluorophosphate, phenyl (4- (2-methylpropyl) phenyl] -iodonium hexa (2-methylpropyl) phenyl] -iodonium hexafluorophosphate, (thiodi-4,1-phenylene) bis (diphenylsulfonium) dihexafluoroantimonate ((Thiodi- 4,1-phenylene) bis (diphenylsulfonium) dihexafluoroantimonate and thiodi-4,1-phenylene bis (diphenylsulfonium) bis (diphenylsulfonium) dihexafluoroantimonate) dihexafluorophosphate), but is limited to at least one selected from the group consisting of No.

It is preferable that the cationic thermal initiator has a starting temperature at the time of decomposition of 60 ° C or more and 150 ° C or less.

The cationic thermal initiator means a compound that produces a cation or a Lewis acid by heat treatment and acts on a cationic polymerizable group such as an epoxy group to initiate a cationic polymerization reaction.

At this time, the cationic thermal initiators generally used in the art can be used without limitation when the cationic thermal decomposition occurs. For example, a sulfonium salt, an ammonium salt, a phosphonium salt, an onium salt, an iodonium salt, and the like. Specific examples thereof include ammonium / antimony hexafluoride, triarylsulfonium hexafluoroantimonate salts, trianylsulfonium hexafluoroantimonate, (Tolylumil) iodonium tetrakis (pentafluorophenyl) borate, Bis (dodecylphenyl) iodonium hexafluoroantimonate, iodonium (4-methylphenyl) (4- (2-methylpropyl) phenyl) hexafluorophosphate, octyldiphenyliodonium hexafluoroantimonate Benzylpyridinium salts, N-benzylpyridinium salts, N-benzylammonium salts, phosphonium salts, hydrazinium salts, ammonium borate salts, triaryl iodonium salts, benzylsulfonium salts, phenacylsulfonium salts, Phenylmethyl chloride, and mixtures thereof. Preferred examples thereof include ammonium / antimony hexafluoride, trianylsulfonium hexafluoroantimonate, triphenylmethyl chloride, and the like. Products include Sanshin Chemical 社 acid - may be used, such as Aid (San Aid) SI-B2A, SI-B3, SI-B3A, SI-300, SI-360.

The content of the cationic photoinitiator and the cationic thermal initiator may be in the range of 0.05 wt% to 10 wt% based on the solid content of the coating composition forming the coating layer, as described above. And preferably 0.1% by weight to 5% by weight.

The coating composition containing the siloxane-based compound having the unit represented by the above-described formula (1) of the present invention has a low viscosity and a good coating property, and thus can be used as a solvent-free type without a solvent. However, it does not exclude the use of an organic solvent, and may contain a small amount of an organic solvent generally used in the art if necessary. The organic solvent may be used in an amount of about 100 parts by weight or less based on 100 parts by weight of the total coating composition.

Examples of the organic solvent include alcohol solvents such as methanol, ethanol, isopropyl alcohol and butanol, alkoxy alcohol solvents such as 2-methoxyethanol, 2-ethoxyethanol and 1-methoxy-2-propanol, Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, methyl propyl ketone and cyclohexanone, propylene glycol monopropyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether , Ether solvents such as diethylene glycol monomethyl ether, diethyl glycol monoethyl ether, diethyl glycol monopropyl ether, diethyl glycol monobutyl ether and diethylene glycol-2-ethylhexyl ether, benzene, toluene, xylene And the like can be used alone or in combination.

Meanwhile, according to one embodiment of the present invention, the coating composition may further include fine particles to impart hardness improvement, anti-blocking property and slipperiness. The fine particles may be at least one selected from the group consisting of organic fine particles and inorganic fine particles. The particle size of the organic or inorganic fine particles may be 10 mu m or less in terms of proper haze and coating thickness, more specifically 10 nm to 10 mu m, preferably 50 nm to 5 mu m, more preferably 100 nm to 3 mu m Lt; / RTI &gt;

The organic fine particles or the inorganic fine particles are not limited as long as they are used for forming a coating layer of a protective film.

The organic fine particles may be at least one selected from organic fine particles made of an acrylic resin, a styrene resin, an epoxy resin and a nylon resin.

More specifically, the organic fine particles may be at least one selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl Acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, n-octyl (meth) acrylate, Acrylates such as polyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl But are not limited to, methylstyrene, m-methylstyrene, p-ethylstyrene, m-ethylstyrene, p-chlorostyrene, m- chlorostyrene, p- chloromethylstyrene, m- chloromethylstyrene, styrenesulfonic acid, m-butoxystyrene, vinyl acetic acid (Meth) acrylonitrile, (meth) acrylonitrile, vinyltoluene, vinyltoluene, vinyltoluene, vinyl propionate, vinyl butyrate, vinyl ether, allyl butyl ether, allyl glycityl ether, (meth) acrylic acid, maleic acid, And (meth) acrylate, but the present invention is not limited thereto.

The organic fine particles may be selected from the group consisting of polystyrene, polymethyl methacrylate, polymethyl acrylate, polyacrylate, polyacrylate-co-styrene, polymethyl acrylate-co-styrene, polymethyl methacrylate- Polyvinyl chloride resin, polycarbonate resin, polyvinyl chloride resin, polybutylene terephthalate, polyethylene terephthalate, polyamide resin, polyimide resin, polysulfone, polyphenylene oxide, polyacetal, epoxy resin, phenol resin, silicone resin, melamine resin, One or more members selected from the group consisting of amine, polydivinylbenzene, polydivinylbenzene-co-styrene, polydivinylbenzene-co-acrylate, polydiallyl phthalate and triallyl isocyanurate polymer, A copolymer may be used, but the present invention is not limited thereto.

The inorganic fine particles may be at least one selected from the group consisting of inorganic fine particles of silicon oxide, titanium dioxide, indium oxide, tin oxide, zirconium oxide and aluminum oxide, but the present invention is not limited thereto.

The total content of the organic and inorganic fine particles may be in the range of 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the solid content of the coating composition forming the coating layer. When the total content of the organic and inorganic fine particles is less than 0.1 part by weight based on 100 parts by weight of the solid content of the coating composition, the effect of improving hardness and scratch resistance is insignificant. When the total content of the organic and inorganic fine particles is more than 20 parts by weight, The coating property becomes poor and the haze value due to the internal scattering becomes too large and the contrast ratio may be lowered.

Meanwhile, the coating layer of the present invention may contain additives other than the above-mentioned components, such as surfactants, antioxidants, UV stabilizers, leveling agents, antifouling agents, antistatic agents, UV absorbers, antifoaming agents, preservatives, . &Lt; / RTI &gt; The content is not particularly limited as it can be varied within a range that does not deteriorate the physical properties of the coating composition of the present invention. For example, about 100 parts by weight based on the solid content of the coating composition for forming the coating layer, about 0.1 to about 10 parts by weight.

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

Applying a coating composition comprising a siloxane-based compound containing a unit represented by the formula (1) on at least one surface of the base film, stretching and thermosetting; Or performing photo-curing after stretching.

In this case, the stretching direction is not particularly limited, and may be stretched in the width direction (TD) or the length (MD) direction, and may be uniaxially or biaxially stretched. The stretching ratio may be 1.05 to 10 times, or 1.2 to 10 times, 1.5 to 5 times, or 1.5 to 3 times, based on the length in the stretching direction. When the stretching ratio satisfies the above range, the coating layer is not cracked and the effect of stretching can be sufficiently achieved.

When the base film is uniaxially stretched before application of the coating composition, it is preferable that the stretching direction after the coating is stretched in the direction perpendicular to the stretching direction before coating the coating composition. For example, if the base film is stretched in the MD direction before application of the coating composition, it may be stretched in the width direction (TD) after application of the coating composition.

When the coating composition is stretched before and after coating, the total stretching ratio is at least 1.1 times, or at least 1.2 times, or at least 1.5 times, at least 25 times, or at most 10 times the total stretching area of the substrate film, Fold or less, or 7 times or less. When the stretching ratio satisfies the above range, the coating layer is not cracked and the effect of stretching can be sufficiently achieved.

Before the stretching, the coating surface of the coating composition may be planarized and dried to volatilize the solvent contained in the coating composition.

The stretching and thermosetting (heat treatment) temperature at the step of stretching and thermosetting the base film coated with the coating composition is at least about 80 캜. Specifically, it is not less than 100 ° C and not more than 220 ° C. More specifically, it is 120 deg. C or higher and 160 deg. C or lower. When the stretching and thermosetting (heat treatment) temperatures satisfy the above range, the thermosetting reaction by the thermal initiator progresses and uniform stretching becomes possible, and a film having a desired appearance and film strength can be obtained. If the stretching and heat treatment temperature is less than 80 캜, the reaction does not occur at the time of opening and the desired film strength can not be obtained. If the stretching temperature and the heat treatment temperature are more than 160 캜, the reaction occurs too rapidly at the opening,

The heat curing (heat treatment) time in the step of stretching and thermosetting the base film coated with the coating composition may be 20 seconds to 10 minutes. Specifically, it may be from 30 seconds to 5 minutes, more specifically from 30 seconds to 2 minutes. When the heat curing (heat treatment) time satisfies the above range, the curing reaction by the thermal initiator sufficiently occurs, and a film having the desired film strength can be obtained.

The method may further include the step of subjecting the coating composition to photo-curing or heat-treating after stretching and thermosetting the applied substrate film.

In the case of performing the heat treatment after the stretching and thermosetting, the heat treatment temperature and time are the same as the stretching and thermosetting (heat treatment) temperature and time in the step of stretching and thermosetting the base film coated with the coating composition.

The polarizer protective film of the present invention obtained by the above process comprises a stretched base film and an oriented coating layer formed on at least one side of the stretched base film. FIG. 1 is a view showing an example of a polarizer protective film obtained by the production method of the present invention, and FIGS. 2 and 3 are views showing a polarizer including a polarizer protective film produced according to an embodiment of the present invention to be.

Since the stretched coating layer is integrated with the stretched substrate film and stretched, it is advantageous to provide a thin polarizer protective film having high adhesion to a base film even without a separate primer layer.

The ultraviolet irradiation amount of the photocuring process may be 20 to 800 mJ / cm ² . The light source for ultraviolet irradiation is not particularly limited as long as it can be used in the technical field to which the present technology belongs. For example, a high pressure mercury lamp, a metal halide lamp, a black light fluorescent lamp and the like can be used.

According to one embodiment of the present invention, the final thickness of the coating layer after stretching and curing may be between 50 nm and 5 탆, and specifically between 100 nm and 5 탆. And more specifically 500 nm to 3 탆. As described above, the oriented coating layer of the present invention can be made thin and exhibit sufficient strength. In addition, even a single coating layer can exhibit sufficient hardness and scratch resistance, and exhibits high adhesiveness to a substrate without a primer layer, so that workability and productivity of the manufacturing process are high.

The coating layer may be formed on only one side of the stretched substrate film, or may be formed on both sides of the base film.

When the coating layer is formed only on one side of the stretched base film, the other side may further include another photocurable coating layer and / or a thermosetting coating layer or other layers, films, or films for imparting functionality have. It is also possible to further form another functional layer on the stretched coating layer.

Thus, when the polarizer protective film of the present invention includes another layer, film or film or the like on the other surface of the stretched base film, the forming method and the step are not limited. For example, a method of coating the base film before stretching and curing after stretching, a method of coating and curing after stretching the base film, a method of coating a layer, a film, or a film formed separately using an adhesive, Film or film may be laminated on the other surface of the stretched substrate film by various methods known in the art, such as a method of laminating the stretched substrate film to the substrate.

In the polarizer protective film of the present invention as described above, a sample is connected to a vibration generator, the sample and the diffusion sheet are overlapped with each other, the vibration is applied for a predetermined time while the load is applied, Scratch resistance can be evaluated.

Further, the polarizer protective film of the present invention may have a pencil hardness of H or more at a load of 500 g.

The polarizer protective film may be laminated on at least one surface of the polarizer, and the polarizer protective film may be provided.

At this time, the polarizer is not particularly limited, and a film made of polyvinyl alcohol (PVA) including a polarizer well-known in the related art, for example, iodine or a dichroic dye, is used.

The polarizer vibrates in various directions and exhibits a characteristic of extracting only light vibrating in one direction from the incident light. This property can be achieved by stretching polyvinyl alcohol (PVA) absorbing iodine with a strong tension. For example, more specifically, there is a method comprising swelling a PVA film by swelling in an aqueous solution, dyeing the swollen PVA film with a dichroic material imparting polarizing properties, stretching the dyed PVA film, ) To align the dichroic dye materials in the stretching direction, and a polarizing step for correcting the color of the PVA film after the stretching step. However, the polarizing plate of the present invention is not limited thereto.

The polarizer according to the present invention may further include an adhesive layer on one side or both sides of the polarizer for attachment of the polarizer and the optical film. For example, the polarizer of the present specification may be a polarizer, The structure may be [coating layer / base film / adhesive layer / polarizer], but is not limited thereto. At this time, the adhesive that can be used in forming the adhesive layer is preferably a water-based or non-aqueous adhesive commonly used in the art.

Examples of the water-based adhesives include polyvinyl alcohol-based adhesives, acrylic adhesives, epoxy-based adhesives, and urethane-based adhesives. Among them, a polyvinyl alcohol-based adhesive is preferable, and a modified polyvinyl alcohol adhesive containing an acetoacetyl group and the like is particularly preferable in view of the adhesive force with a polarizer and the like. Specific examples of the polyvinyl alcohol-based adhesive include, but are not limited to, Japanese synthetic chemicals Gohsefiner Z-100, Z-200, Z-200H, Z-210, Z-220 and Z-320.

The adhesion of the polarizer to the optical film using the water-based adhesive may be performed by first coating an adhesive on the surface of the optical film or the PVA film as a polarizer using a roll coater, a gravure coater, a bar coater, a knife coater or a capillary coater And the protective film and the polarizing film are thermally pressed or compressed at room temperature by a ply roll before the adhesive is completely dried. When a hot-melt type adhesive is used, a hot press roll is used.

On the other hand, the non-aqueous adhesive is preferably an ultraviolet curing type and is not particularly limited. For example, an adhesive using a photo radical polymerization reaction such as a (meth) acrylate adhesive, an ene / thiol adhesive or an unsaturated polyester adhesive And an adhesive using a photo cationic polymerization reaction such as an epoxy adhesive, an oxetane adhesive, an epoxy / oxetane adhesive, and a vinyl ether adhesive. The adhesion of the polarizer to the optical film using the non-aqueous adhesive is performed by applying an adhesive composition to form an adhesive layer, then laminating the polarizer and the optical film, and curing the adhesive composition through light irradiation.

According to an embodiment of the present invention, the polarizer protective film may be attached to both surfaces of the polarizer.

When the polarizer protective film of the present invention is laminated on the polarizer and adhered, it is preferable that the base film is attached to the polarizer.

According to an embodiment of the present invention, the liquid crystal display comprises a liquid crystal cell; An upper polarizer provided on an upper portion of the liquid crystal cell; A lower polarizer disposed on a lower portion of the liquid crystal cell; And a backlight unit provided on a lower portion of the lower polarizer, wherein the lower polarizer comprises a polarizer; And the above-described polarizer protective film disposed on one side or both sides of the polarizer.

The polarizing plate including the polarizer protective film of the present invention can be provided as a lower polarizing plate of a liquid crystal display device.

In addition, the polarizing plate including the polarizer protective film of the present invention may be a lower polarizing plate of a liquid crystal display, and the polarizing plate protective film of the present invention may be disposed to face the backlighting unit.

As described above, when the polarizer protective film is laminated on the LCD and the polarizer is stacked on the LCD, the lower protective film of the polarizer is damaged by abutting against the backlight unit provided under the polarizer, thereby exhibiting excellent optical properties.

According to another embodiment of the present invention, the polarizer protective film is provided on only one side of the polarizer, and the general protective film commonly used for protecting the polarizer may be provided on the other side.

The polarizing plate having the protective film of the present invention is applied to an LCD, but the present invention is not limited thereto and can be applied to various fields. For example, mobile communication terminals, smart phones, other mobile devices, display devices, electronic blackboards, outdoor electronic signboards, and various displays. According to an embodiment of the present invention, the polarizing plate may be a TN (Twisted Nematic) or STN (Super Twisted Nematic) liquid crystal polarizing plate, and may be an IPS (In-Plane Switching), a Super-IPS, a Fringe Field Switching Or a polarizing plate for the vertical alignment mode.

4 is a diagram showing a liquid crystal display device including a polarizer protective film manufactured by the manufacturing method of the present invention.

The backlight unit includes a light source that emits light from the back surface of the liquid crystal panel. The type of the light source is not particularly limited, and a general LCD light source such as CCFL, HCFL, or LED can be used.

Best Mode for Carrying Out the Invention Hereinafter, the function and effect of the present invention will be described in more detail through specific examples of the present invention. It is to be understood, however, that these embodiments are merely illustrative of the invention and are not intended to limit the scope of the invention.

< Example >

Preparation of coating compositions

Manufacturing example  One.

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Momentive, Silquest A-186) and 3- glycidoxypropyltrimethoxysilane [3 (4-epoxycyclohexyl) ethyltrimethoxysilane -Glycidoxypropyltrimethoxysilane (Momentive, Silquest A-187) was subjected to a sol-gel condensation reaction with a small amount of water at a weight ratio of 2: 1 to obtain a polymer having a number average molecular weight (Mn) of 1170 and a weight average molecular weight (Mw ) &Lt; / RTI &gt; of 2480 was obtained. 100 g of the obtained silane compound was mixed with 3 g of cationic photopolymerization initiator CPI-100p (San-Apro) to prepare a cationically curable coating composition.

Manufacturing example  2.

(Momentive, Silquest A-186) and methyltrimethoxysilane (Momentive, Inc., Momentive, Inc.) were added to a solution of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Silquest A-1630A) was subjected to sol-gel condensation reaction with a small amount of water at a weight ratio of 2: 1 to obtain an alicyclic epoxy resin having a number average molecular weight (Mn) of 1100 and a weight average molecular weight (Mw) To obtain a silane compound. 100 g of the obtained silane compound was mixed with 3 g of a cationic photoinitiator CPI-100p (San-Apro) to prepare a cation-curable coating composition.

Manufacturing example  3.

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Momentive, Silquest A-186) and 3- glycidoxypropyltrimethoxysilane [3 (4-epoxycyclohexyl) ethyltrimethoxysilane -Glycidoxypropyltrimethoxysilane] (Momentive, Silquest A-187) was subjected to sol-gel condensation reaction with a small amount of water at a weight ratio of 2: 1 to obtain a polymer having a number average molecular weight (Mn) of 1170 and a weight average molecular weight ) &Lt; / RTI &gt; of 2480 was obtained. To 100 g of the obtained silane compound, 0.15 g of a cationic thermal initiator San-Aid SI-B3A (Sanshin Chemical Co.) was mixed to prepare a cationically curable coating composition.

Manufacturing example  4.

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Momentive, Silquest A-186), 3- glycidoxypropyltrimethoxysilane [3 (4-Epoxycyclohexyl) Gel condensation reaction at a weight ratio of 4: 2: 3 was carried out at a weight ratio of 4: 2: 3: glycidoxypropyltrimethoxysilane (Momentive, Silquest A-187) and methyltrimethoxysilane (Momentive, Silquest A- To obtain a silane compound containing an alicyclic epoxy group having a number average molecular weight (Mn) of 1280 and a weight average molecular weight (Mw) of 2970. To 100 g of the obtained silane compound, 0.15 g of a cationic thermal initiator San-Aid SI-B3 (Sanshin Chemical Co.) was mixed to prepare a cationically curable coating composition.

Manufacturing example  5.

A coating composition was prepared in the same manner as in Preparation Example 1 except that 0.3 g of Tego Rad 2250 (Tego) was added as a silicone compound in Preparation Example 1.

Polarizer  Manufacture of protective film

Example  One.

The polymethyl methacrylate resin was subjected to a T-die-peeling process under the condition of 250 占 폚 to prepare an undrawn film having a width of 800 mm and a thickness of 200 占 퐉. The unstretched film was stretched 1.8 times in the length (MD) direction at a temperature of 135 캜 to prepare a uniaxially stretched film.

The coating composition of Preparation Example 1 was coated on the above uniaxially stretched film by a bar coating method and then stretched 2.5 times in the width direction (TD) at a temperature of 135 占 폚, A polarizer protective film having a phosphor coating layer formed thereon was prepared.

Example  2.

A polarizer protective film was prepared in the same manner as in Example 1, except that the coating composition of Production Example 2 was used in place of the coating composition of Production Example 1.

Example  3.

The polymethyl methacrylate resin was subjected to a T-die-peeling process under the condition of 250 占 폚 to prepare an undrawn film having a width of 800 mm and a thickness of 200 占 퐉. The unstretched film was stretched 1.8 times in the length (MD) direction at a temperature of 135 캜 to prepare a uniaxially stretched film.

The coating composition of Preparation Example 3 was coated on the uniaxially stretched film by a bar coating method and then stretched 2.5 times in the direction of width (TD) at a temperature of 135 占 폚 and then subjected to additional heat treatment at the same temperature for 1 minute To prepare a polarizer protective film on which a coating layer having a thickness of 2 m was formed.

Example  4.

A polarizer protective film was prepared in the same manner as in Example 3, except that the coating composition of Production Example 4 was used in place of the coating composition of Production Example 3.

Example  5.

A polarizer protective film was prepared in the same manner as in Example 1, except that the coating composition of Production Example 5 was used in place of the coating composition of Production Example 1.

Comparative Example  One.

The polymethyl methacrylate resin was subjected to a T-die-peeling process under the condition of 250 占 폚 to prepare an undrawn film having a width of 800 mm and a thickness of 200 占 퐉. The unstretched film was sequentially stretched at 135 占 폚 in the MD (MD) direction and 2.5 times in the width (TD) direction without additional coating process to prepare a polarizer protective film.

Comparative Example  2.

The polymethyl methacrylate resin was subjected to a T-die-peeling process under the condition of 250 占 폚 to prepare an undrawn film having a width of 800 mm and a thickness of 200 占 퐉. The coating composition of Preparation Example 1 was applied onto a biaxially stretched acrylic film obtained by sequentially drawing the above unstretched film at a temperature of 135 캜 at a temperature of 135 占 폚 in a longitudinal direction (MD) direction of 1.8 times and in a width direction (TD) Coating method, and then irradiated with ultraviolet rays to prepare a polarizer protective film having a coating layer having a thickness of 2 탆.

Comparative Example  3.

The polymethyl methacrylate resin was subjected to a T-die-peeling process under the condition of 250 占 폚 to prepare an undrawn film having a width of 800 mm and a thickness of 200 占 퐉. The unstretched film was stretched 1.8 times in the direction of the length (MD) at a temperature of 135 캜 and then coated with a water-dispersed urethane coating liquid (CK-PF, dimmer paint) having a solid content of 8w% Stretched 2.5 times in the direction of the width (TD) to form a polarizer protective film having a coating layer having a thickness of about 0.3 탆.

< Experimental Example  >

<Measurement method>

Physical properties of the polarizer protective films of Examples and Comparative Examples were measured by the following methods.

1) scratch resistance

The coating layer of the polarizer protective film of the examples and comparative examples and the diffusion sheet (LG Electronics Inc., ND146) were put in contact with each other in a sample folder (50 mm x 50 mm) to which the vibration generator was connected, Vibration (applied vibration intensity 2.8 Grams, frequency 20-60 Hz) was applied for 240 seconds. Then scratch resistance was evaluated on the surface of the coating layer and the surface of the diffusion sheet of the polarizer protective film with or without scratches. If there is no scratch or cracking, the symbol is marked with &amp; cir &amp;

2) Pencil Hardness

The pencil hardness was measured under a load of 500 g using a pencil hardness tester (hardness tester, manufacturer: Chungbuk Tech). A standard pencil (Mitshbishi) was changed from 6B to 9H according to ASTM 3363-74, and the surface of the coating layer was subjected to scratching by keeping the angle of 45 °. Each experimental value was described as an average value after 5 measurements.

The results of the physical properties measurement are shown in Table 1 below.

Scratch resistance Pencil hardness Remarks Example 1 ○ 3H Example 2 ○ 3H Example 3 ○ 2H Example 4 ○ 2H Example 5 ○ 2H Comparative Example 1 X HB Comparative Example 2 X 2H Film peeling occurred in evaluation of scratch resistance Comparative Example 3 X 2B

From the above Table 1, it can be seen that the polarizer protective film produced according to the production method of the present invention has a comparative example 1 in which only a base film is biaxially stretched without a coating layer formed, and that the coating composition contains an aqueous dispersed urethane compound which is not a siloxane compound It is confirmed that the scratch resistance and the pencil hardness are superior to those of Comparative Example 3. In addition, it is confirmed that the scratch resistance and the adhesion between the base film and the coating layer are not very good in Comparative Example 2 in which photocuring is performed after the application of the coating composition without drawing.

10: Upper polarizer
20: liquid crystal cell
30: Lower polarizer plate
34: polarizer protective film
40: Backlight unit
41: Light emitted from the backlight unit

Claims (11)

Applying a coating composition comprising a siloxane-based compound on at least one side of the substrate film; And
Stretching and thermosetting the substrate film coated with the coating composition; Or after stretching the substrate film coated with the coating composition, performing photo-curing on the coating composition. The method according to claim 1,
Wherein the siloxane-based compound comprises a unit represented by the following formula (1).
[Chemical Formula 1]

In Formula 1,
R ₁ is a linear or branched alkyl group containing an alicyclic epoxy group,
R ₂ and R ₃ are the same or different and each independently represent a hydroxyl group (-OH); Or an alkoxy group having 1 to 5 carbon atoms,
R ₄ is a substituted or unsubstituted straight or branched alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a straight or branched alkyl group containing a glycidyl ether group,
m and n are each an integer of 1 to 20, and when n is 2 or more, the structures in parentheses are the same or different from each other. The method according to claim 1,
Wherein the siloxane-based compound has a weight average molecular weight of 500 to 5,000 g / mol. The method according to claim 1,
Wherein the coating composition comprises from 50% by weight to 99.95% by weight of a siloxane-based compound. The method according to claim 1,
Wherein the coating composition further comprises a cationic photoinitiator or a cationic thermal initiator. The method according to claim 1,
Wherein the coating composition further comprises a curable resin comprising an epoxy compound, an acrylate compound or a mixture thereof. The method according to claim 1,
Wherein the coating composition further comprises a silicone-based or fluorine-based compound. The method according to claim 1,
Wherein the coating composition further comprises fine particles. The method according to claim 1,
Stretching and thermosetting the base film; Or the stretching ratio in the step of performing photo-curing after stretching the base film is 1.05 to 10 times the length in the stretching direction. The method according to claim 1,
After the step of stretching and thermosetting the base film to which the coating composition is applied,
Further comprising the step of performing photocuring or heat treatment on the coating composition. The method according to claim 1,
Prior to applying the coating composition on at least one side of the substrate film,
Further comprising the step of stretching the base film.

Images