KR101960584B1 - Composition for window film and flexible window film prepared using the same - Google Patents

Abstract

A curable resin, a crosslinking agent, and an initiator, wherein the curable resin comprises a composition for a window film comprising a first silicone resin of formula (I) and a flexible window film formed therefrom.

Description

FIELD OF THE INVENTION The present invention relates to a composition for a window film,

The present invention relates to a composition for a window film and a flexible window film formed therefrom. More particularly, the present invention relates to a composition for a window film capable of realizing a window film excellent in impact resistance, hardness and flexibility, and a flexible window film formed therefrom.

Flexible display devices have been developed that can be folded and unfolded while replacing a glass substrate or a hardened substrate with a film in a display device. The flexible display device is thin, light, strong against impact, and can be folded and unfolded. The window film is positioned at the outermost portion of the display device, so that flexibility and hardness are good.

On the other hand, optical elements included in the display device are damaged due to an external shock, and many of them fail to implement their functions properly. For example, an organic light emitting element and the like are easily damaged by an external impact and may be less reliable when damaged. In order to compensate for this, a large number of impact resistance improving materials such as various films and glass may be included in the display device. However, in this case, it is difficult to thin the display device and the manufacturing process may become complicated. Therefore, there is a demand for a window film which can prevent the optical element from being damaged by increasing the impact resistance against an external impact.

The background art of the present invention is disclosed in Japanese Laid-Open Patent Application No. 2007-176542.

A problem to be solved by the present invention is to provide a composition for a window film which can realize a window film excellent in impact resistance.

Another object of the present invention is to provide a composition for a window film which is excellent in impact resistance and can realize a window film capable of suppressing damage to an optical element such as an organic light emitting element.

Another object of the present invention is to provide a composition for a window film which can realize a window film excellent in hardness and flexibility.

Another object of the present invention is to provide a flexible window film excellent in impact resistance, hardness and flexibility.

The composition for a window film of the present invention comprises a curable resin, a crosslinking agent and an initiator, and the curable resin may comprise a first silicone resin having the following formula:

≪ Formula 1 >

(R ¹ SiO _3/2 ) _x (R ² R ³ SiO _2/2 ) _y (SiO _3/2 -R ⁴ -R ⁵ -SiO _3/2 ) _z

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , x, y and z are as defined in the detailed description of the present invention).

The flexible window film of the present invention includes a base layer and a coating layer formed on the base layer, and the coating layer may be formed of the composition for a window film of the present invention.

The present invention provides a composition for a window film capable of realizing a window film excellent in impact resistance.

The present invention provides a composition for a window film which is excellent in impact resistance and can realize a window film capable of suppressing damage to an optical element such as an organic light emitting element.

The present invention provides a composition for a window film capable of realizing a window film excellent in hardness and flexibility.

The present invention provides a flexible window film excellent in impact resistance, hardness and flexibility.

1 is a cross-sectional view of a flexible window film according to an embodiment of the present invention.
2 is a cross-sectional view of a flexible window film according to another embodiment of the present invention.
3 is a cross-sectional view of a flexible window film according to another embodiment of the present invention.
4 is a cross-sectional view of a flexible display device according to an embodiment of the present invention.
5 is a cross-sectional view according to an embodiment of the display unit of FIG.
6 is a cross-sectional view of a flexible display device according to another embodiment of the present invention.
7 is a cross-sectional view of a flexible display device according to another embodiment of the present invention.

The present invention is not limited to the above embodiments and various changes and modifications may be made by those skilled in the art without departing from the scope of the present invention. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

The terms "upper" and "lower" in this specification are defined with reference to the drawings, wherein "upper" may be changed to "lower", "lower" What is referred to as " on " may include not only superposition, but also intervening other structures in the middle. On the other hand, what is referred to as " directly on " or " directly above "

As used herein, the term " epoxy group " means a glycidyl group, a glycidoxin group or an epoxidized C4 to C20 cycloalkyl group, and an " epoxy group-containing functional group " means a C5 to C20 cycloalkyl group having a C1 to C20 alkyl group or an epoxy group having an epoxy group to be.

As used herein, " halogen " means fluorine, chlorine, bromine or iodine.

As used herein, unless specifically stated otherwise, at least one hydrogen atom of the functional group may be replaced by a hydroxyl group, an unsubstituted C1 to C10 alkyl group, a C1 to C10 alkoxy group, a C3 to C10 cycloalkyl group, C20 aryl group, a C7 to C20 arylalkyl group, a C6 to C20 aryl group substituted with a C1 to C10 alkyl group, or a C1 to C10 alkyl group substituted with a C1 to C10 alkoxy group.

In the present specification, "Ec" is 2- (3,4-epoxycyclohexyl) ethyl group, "Gp" is 3-glycidoxypropyl group, "Me" is methyl group and "Et"

As used herein, "(meth) acrylate" means acrylate and / or methacrylate. As used herein, the term "(meth) acrylate group-containing functional group" means a C 1 to C 20 alkyl group having a (meth) acrylate group or a C 5 to C 20 cycloalkyl group having a (meth) acrylate group.

In the present specification, the "oxetane group-containing functional group" means a C5 to C20 cycloalkyl group having a C1 to C20 alkyl group or oxetane group having an oxetane group.

In this specification, the "modulus" of the adhesive layer is a storage modulus and is measured using a dynamic viscoelasticity measuring device ARES (Anton Paar MCR-501) at a shear rate of 1 rad / sec, strain 1% The viscoelasticity was measured. After removing the release film, the adhesive layer was laminated to a thickness of 500 mu m and the laminate was punched with a perforator having a diameter of 8 mm and used as a specimen. Measurement was carried out at a temperature rise rate of 5 DEG C / min in a temperature range of -60 DEG C to 90 DEG C using an 8 mm jig, and the modulus was recorded at -20 DEG C, 25 DEG C and 80 DEG C.

The " average particle diameter " of the organic nanoparticles in the present specification is the particle diameter of the organic nanoparticles expressed by the Z-average value measured by a Zetasizer nano-ZS instrument of Malvern, .

Hereinafter, a composition for a window film according to an embodiment of the present invention will be described.

The composition for a window film according to an embodiment of the present invention may include a first silicone resin of the following formula 1, a crosslinking agent and an initiator:

≪ Formula 1 >

(R ¹ SiO _3/2 ) _x (R ² R ³ SiO _2/2 ) _y (SiO _3/2 -R ⁴ -R ⁵ -SiO _3/2 ) _z

Wherein R ¹ is an epoxy group, an epoxy group-containing functional group, a (meth) acrylate group, a (meth) acrylate group-containing functional group, an oxetane group or an oxetane group-

R ² and R ³ are each independently a hydrogen atom or a substituted or unsubstituted C1 to C12 alkyl group,

R ⁴ is a single bond, a substituted or unsubstituted C1 to C16 alkylene group, a substituted or unsubstituted C6 to C20 cycloalkylene group, or a substituted or unsubstituted C6 to C20 arylene group,

R ⁵ is a single bond, a substituted or unsubstituted C 1 to C 16 alkylene group, a substituted or unsubstituted C 6 to C 20 arylene group, a substituted or unsubstituted C 6 to C 20 cycloalkylene group, a substituted or unsubstituted C 7 to C - (- OR ^a -) n- (wherein R ^a is a substituted or unsubstituted C1 to C5 alkylene group, and n is an integer of 1 to 5)

0 <x <1, 0 <y <1, 0 <z <1, x + y + z = 1).

The composition for a window film of the present invention contains a first silicone resin of the above formula (1) as a curable resin, thereby realizing a window film having excellent impact resistance, hardness and flexibility. In particular, the present invention can provide a window film having excellent impact resistance and hardness as well as extreme flexibility with a radius of curvature of 2.0 mm or less by including the first silicone resin of Formula (1). The first silicone resin of Formula 1 may be cured by an initiator. (R ¹ SiO _3/2) forms the matrix of the window film as a unit which is cured with a crosslinking agent by the initiator, and can increase the hardness and flexibility. _{^{(R 2 R 3 SiO 2/}} 2) can improve the impact resistance and the flexibility of the window film. ^{_{(SiO 3/2 -R 4 -R}} 5 -SiO 3/2) can improve the hardness, flexibility and appearance of the window film.

Specifically, R ¹ may be a C1 to C10 alkyl group having a glycidoxy group or an epoxidized C4 to C10 cycloalkyl group as an epoxy group-containing functional group. Preferably, R ¹ may be a C1 to C5 alkyl group having a glycidoxy group or a C1 to C5 alkyl group having an epoxidized C4 to C10 cycloalkyl group, more preferably a 3-glycidoxypropyl group Or a 2- (3,4-epoxycyclohexyl) ethyl group. Specifically, each of R ² and R ³ may independently be a C1 to C10 alkyl group, preferably a C1 to C7 alkyl group or a C1 to C5 alkyl group, preferably a methyl group, an ethyl group, or a propyl group . Specifically, R ⁴ may be a single bond, a C1 to C5 alkylene group, or a C6 to C10 arylene group. Specifically, R ⁵ represents a single bond, a C1 to C10 alkylene group, a C6 to C10 arylene group or - (-O-CH ₂ CH ₂ -) n- (n is an integer of 1 to 5) -CH ₂ CH ₂ CH ₂ -) n - (n is an integer of 1 to 5) or - (-O-CH (CH ₃ ) CH ₂ - . Preferably, the case where R ⁴ and R ⁵ are both a single bond is excluded.

Specifically, 0 <x? 0.90, 0? Y? 0.90, 0? Z? 0.50, and x + y + z = 1 in the formula (1). Within this range, both the hardness, flexibility and impact resistance of the window film can be improved and the curl can be reduced. Preferably, 0.01? X? 0.90, 0.01? Y? 0.90, 0.05? Z? 0.50, only x + y + z = 1, 0.05? X? 0.80, 0.10? Y? 0.80, x + y + z = 1, more preferably 0.10? x? 0.55, 0.30? y? 0.80, 0.05? z? 0.30, and x + y + z = 1. Within this range, there may be more impact resistance effect of the window film.

In one embodiment, the first silicone resin of Formula 1 may be represented by any of Formulas 1-1 through 1-8:

&Lt; Formula 1-1 >

(EcSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z

(1-2)

(GpSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z

<Formula 1-3>

(EcSiO _3/2 ) _x ((Et) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z

<Formula 1-4>

(GpSiO _3/2 ) _x ((Et) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z

&Lt; Formula 1-5 >

(EcSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ CH ₂ -SiO _3/2 ) _z

<Formula 1-6>

(GpSiO _3/2 ) x ((Me) ₂ SiO _2/2 ) y (SiO _3/2 -CH ₂ CH ₂ CH ₂ -SiO _3/2 ) z

<Formula 1-7>

(EcSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ - (-OCH ₂ CH ₂ -) n -SiO _3/2 ) _z

&Lt; Formula (1-8)

(GpSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ - (-OCH ₂ CH ₂ -) n -SiO _3/2 ) _z

1, 0 < z < 1, x + y + z = 1, n are as defined in the above formula (1).

In the above formulas 1-1 to 1-8, x, y and z may include the ranges described in the above formula (1).

The first silicone resin of Formula 1 may have a weight average molecular weight of from 2,000 g / mol to 100,000 g / mol, specifically from 2,000 g / mol to 50,000 g / mol, more specifically from 4,000 g / mol to 35,000 g / mol have. In this range, the transparency of the window film can be improved and the hardness and impact resistance of the window film can be improved. The first silicone resin of Formula 1 may have a polydispersity index (PDI) of 1.0 to 10. In the above range, the coating property of the composition is good and the coating property may be stable.

The crosslinking agent contains a crosslinkable functional group, which can be cured by the initiator with the first silicone resin of Formula 1 to increase the hardness of the window film and improve flexibility. The crosslinking agent may further include at least one of a chain type aliphatic hydrocarbon group, a cyclic aliphatic hydrocarbon group, and a hydrogenated aromatic hydrocarbon group to further increase the flexibility of the window coating layer. The crosslinking agent may include at least one of a chain type aliphatic epoxy monomer, a cyclic aliphatic epoxy monomer, a hydrogenated aromatic hydrocarbon epoxy monomer, an oxetane monomer, and a (meth) acrylic monomer, and these may be included singly or in combination.

The chain type aliphatic epoxy monomer may be 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylol propane triglycidyl ether, polyethylene glycol diglycidyl ether, Cidyl ether, glycerin triglycidyl ether, polypropylene glycol diglycidyl ether; Polyglycidyl ethers of polyether polyols obtained by adding one or more alkylene oxides to aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin; Diglycidyl esters of aliphatic long chain dibasic acids; Monoglycidyl ethers of aliphatic higher alcohols; Glycidyl ethers of higher fatty acids; Epoxidized soybean oil; Butyl stearate; Octyl stearate; Epoxidized linseed oil; Epoxylated polybutadiene, and the like.

The cyclic aliphatic epoxy monomer is a compound having at least one epoxy group in the alicyclic group, and may specifically include an alicyclic epoxy carboxylate, an alicyclic epoxy (meth) acrylate, and the like. More specifically, (3,4-epoxycyclohexyl) methyl-3 ', 4'-epoxycyclohexanecarboxylate, diglycidyl 1,2-cyclohexanedicarboxylate, 2- (3,4- Epoxycyclohexyl) -5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxy-6-methylcyclohexyl) adipate, 3,4- Cyclohexylmethyl-3 ', 4'-epoxy-6'-methylcyclohexanecarboxylate, ε-caprolactone modified 3,4-epoxycyclohexylmethyl-3', 4'-epoxycyclohexanecarboxylate, trimethyl Caprolactone-modified 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate, β-methyl-δ-valerolactone-modified 3,4-epoxycyclohexylmethyl- Epoxycyclohexanecarboxylate, 1,4-cyclohexanedimethanol bis (3,4-epoxycyclohexanecarboxylate), di (3,4-epoxycyclohexylmethyl) ether of ethylene glycol, ethylenebis (3, 4-epoxycyclohexane (3,4-epoxycyclohexylmethyl) adipate, 4-vinylcyclohexene-oxide, vinylcyclohexene monoxide (vinylcyclohexylmethoxide) And the like.

The hydrogenated aromatic hydrocarbon epoxy monomer means a compound obtained by selectively hydrogenating an aromatic epoxy monomer under a pressure in the presence of a catalyst. Aromatic epoxy monomers include, for example, bisphenol-type epoxy resins such as diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, diglycidyl ether of bisphenol S and the like; Novolak type epoxy resins such as phenol novolak epoxy resin, cresol novolak epoxy resin, and hydroxybenzaldehyde phenol novolak epoxy resin; Glycidyl ethers of tetrahydroxyphenylmethane, glycidyl ethers of tetrahydroxybenzophenone, and epoxy polyvinylphenols, and the like.

The oxetane monomer may be selected from the group consisting of 3-methyloxetane, 2-methyloxetane, 2-ethylhexyloxetane, 3-oxethanol, 2-methylene oxetane, Methyl-3-oxetanemethanamine, N- (1,2-dimethylbutyl) -3-methyl-3- (3-ethyloxetan-3-yl) methoxy] butan-1-ol, 3-ethyloxetane- May include at least one of 3-hydroxymethyloxetane, xylene bisoxetane and 3- [ethyl-3 [[(3-ethyloxetan-3-yl)] methoxy] methyl] oxetane, But is not limited thereto.

The (meth) acrylic monomer may be 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) (Meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate, ethylene oxide modified di (meth) acrylate, di (Meth) acrylate, trimethylolpropane di (meth) acrylate, acryloyloxyethyl isocyanurate, allyl cyclohexyl di (meth) acrylate, tricyclodecane dimethanol Acrylate, neopentyl glycol modified trimethylpropane di (meth) acrylate, adamantane di (meth) acrylate, di (meth) acrylate, tricyclodecane dimethanol Acrylate or 9,9-bis bifunctional (meth) acrylates such as [4- (2-oxy-acrylic) phenyl] fluorene; (Meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide Trifunctional (meth) acrylates such as modified trimethylolpropane tri (meth) acrylate, trifunctional urethane (meth) acrylate or tris (meth) acryloxyethylisocyanurate; Tetrafunctional (meth) acrylates such as diglycerin tetra (meth) acrylate or pentaerythritol tetra (meth) acrylate; Pentafunctional (meth) acrylates such as dipentaerythritol penta (meth) acrylate; (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol hexa (meth) acrylate or urethane (meth) acrylate (ex. Isocyanate monomer and trimethylol propane tri Hexafunctional (meth) acrylate such as a reaction product, etc., but are not limited thereto. These may be used alone or in combination of two or more.

Preferably, the effect of the present invention can be further enhanced by using a cyclic aliphatic epoxy monomer.

The crosslinking agent may be contained in an amount of 1 part by weight to 50 parts by weight, specifically 1 part by weight to 40 parts by weight, 1 part by weight to 30 parts by weight, and 5 parts by weight to 30 parts by weight based on 100 parts by weight of the curable resin. The flexibility, hardness, curling and optical properties of the coating layer can be ensured within the above range.

The initiator cures the first silicone resin of Formula 1 and the crosslinking agent. One or more of a photocationic initiator and a photoradical initiator may be used, or they may be used alone or in combination. As the Gwangyang ionic initiator, any one ordinarily known to those skilled in the art can be used, and onium salts including cations and anions can be used. Specifically, the cation is at least one selected from the group consisting of diphenyl iodonium, 4-methoxydiphenyl iodonium, bis (4-methylphenyl) iodonium, bis (4-tert- butylphenyl) iodonium, bis (dodecylphenyl) Triarylsulfonium such as diaryliodonium such as [methylphenyl] [4- (2-methylpropyl) phenyl] iodonium, triphenylsulfonium and diphenyl-4-thiophenoxyphenylsulfonium, bis [4 - (diphenylsulfonio) phenyl] sulfide, and the anions include hexafluorophosphate, tetrafluoroborate, hexafluoroantimonate, hexafluoroarsenate, hexachloroantimonate, etc. .

The initiator may be included in an amount of 0.1 to 10 parts by weight, specifically 0.5 to 5 parts by weight, based on 100 parts by weight of the curable resin. In this range, the silicone resin can be sufficiently cured and the remaining amount of the initiator remains, thereby preventing the optical characteristics (transmittance, hue, and light reliability) of the window film from being lowered.

The composition for a window film according to this embodiment may further include nanoparticles.

Nanoparticles can further increase the hardness of the window film. The nanoparticles may include, but are not limited to, one or more of silica, aluminum oxide, zirconium oxide, and titanium oxide. The nanoparticles may be surface treated with some or all of the surface of the silicone compound for mixing with the silicone resin. Nanoparticles are not limited in shape and size. Specifically, the nanoparticles may include spherical, plate-like, amorphous, etc. particles. The nanoparticles may have an average particle diameter (D50) of 1 nm to 200 nm, specifically 10 nm to 50 nm. The hardness of the window film can be increased without affecting the surface roughness and transparency of the window film in the above range. The nanoparticles may be contained in an amount of 0.1 to 60 parts by weight, specifically 10 to 50 parts by weight, based on 100 parts by weight of the curable resin. The hardness of the window film can be increased without affecting the surface roughness and transparency of the window film in the above range.

The composition for a window film according to this embodiment may further include an additive. The additive may provide additional functionality to the window film. The additive may include an additive typically added to the window film. Specifically, the additive may include, but is not limited to, at least one of a UV absorber, a reaction inhibitor, an adhesion improver, a thixotropic agent, a conductivity-imparting agent, a colorant-adjusting agent, a stabilizer, an antistatic agent and an antioxidant. The reaction inhibitor may include ethynylcyclohexane. The adhesion improver may include a silane compound having an epoxy or alkoxysilyl group. The thixotropic agent may include pyrous silica and the like. The conductivity-imparting agent may include a metal powder such as silver, copper aluminum and the like. The colorant-adjusting agent may include a pigment, a dye, and the like. The UV absorber can increase the light reliability of the window film. The UV absorbers can be conventional absorbents known to those skilled in the art. Specifically, the UV absorber may include, but is not limited to, one or more UV absorbers based on triazine, benzimidazole, benzophenone, and benzotriazole. The additive may be included in an amount of 0.01 to 5 parts by weight, specifically 0.1 to 3 parts by weight based on 100 parts by weight of the curable resin. In this range, the hardness and flexibility of the window film can be improved and the additive effect can be realized.

The composition for a window film according to this embodiment may further include a solvent to facilitate coating, coating or processability. The solvent may include, but is not limited to, one or more of methyl ethyl ketone (MEK, methylethylketone), methyl isobutyl ketone, and propylene glycol monomethyl ether acetate.

Hereinafter, a composition for a window film according to another embodiment of the present invention will be described.

The composition for a window film according to the present embodiment is a composition for a window film according to an embodiment of the present invention, except that it further comprises a second silicone resin of the following formula (2) in addition to the first silicone resin of the formula (1) . The curable resin includes the first silicone resin of Formula 1 and the second silicone resin of Formula 2 below. By further including a second silicone resin represented by the following formula (2) as a curable resin, a further hardening effect can be obtained. Hereinafter, only the second silicone resin of the following formula (2) will be described.

The second silicone resin is a binder for forming a window film, which can improve the hardness and flexibility of the window film and can be represented by the following formula (2)

(2)

(R ⁶ SiO _3/2 ) _x (R ⁷ R ⁸ SiO _2/2 ) _y (R ⁹ R ¹⁰ R ¹¹ SiO _1/2 ) _z (SiO _4/2 ) _w

(Wherein R ⁶ represents an epoxy group, an epoxy group-containing functional group, a (meth) acrylate group, a (meth) acrylate group-containing functional group, an oxetane group or oxetane group-

R ⁷ and R ⁸ are each independently hydrogen, a crosslinkable functional group, an unsubstituted or substituted C 1 to C 20 alkyl group, or an unsubstituted or substituted C 5 to C 20 cycloalkyl group,

R ⁹ , R ¹⁰ and R ¹¹ are each independently selected from the group consisting of hydrogen, a crosslinkable functional group, an unsubstituted or substituted C 1 to C 20 alkyl group, an unsubstituted or substituted C 5 to C 20 cycloalkyl group, An aryl group of C30,

0 &lt; y < 1, 0? Y <1, 0? Z <1, 0? W <1, x + y + z + w = 1).

Specifically, R ⁶ is a C1 to C20 alkyl group having an epoxidized C4 to C20 cycloalkyl group, or a C1 to C20 alkyl group having a glycidoxy group, more specifically an epoxycyclohexylethyl group, or a glycidoxypropyl group have. Specifically, R ⁷ and R ⁸ may be independently a C1 to C20 alkyl group having a C4 to C20 cycloalkyl group which is epoxidized, a C1 to C10 alkyl group, more specifically an epoxycyclohexylethyl group or a methyl group. In the formula (2), the crosslinkable functional group means an epoxy group, an epoxy group-containing functional group, a (meth) acrylate group, a (meth) acrylate group-containing functional group, an oxetanyl group or an oxetanyl group-containing functional group.

In one embodiment, the second silicone resin may be represented by the following formula 2-1, 2-2, 2-3, 2-4, or 2-5:

&Lt; Formula (2-1)

(R ^6a SiO _3/2 ) _{x 1} (R ^6b SiO _3/2 ) _{x 2}

(In the above formula 2-1, R ^6a, R ^6b is an epoxy group or the epoxy group-containing functional group, 0≤x1 <1, 0≤x2 <1 , x1 + x2 = 1, x1 + x2 ≠ 0, R 6a and R ^6b are Different from each other)

&Lt; Formula (2-2)

(R ^6a SiO _3/2 ) _{x 1} (R ^6b SiO _3/2 ) _{x 2} (SiO _4/2 ) _w

(In the above formula 2-2, R ^6a, R ^6b is an epoxy group or the epoxy group-containing functional group, 0 <x1 <1, 0 <x2 <1, 0 <w <1, x1 + x2 + w = 1, R 6a and R ^6b are different).

<Formula 2-3>

^{_{(R 6 SiO 3/2) x (}} R 7 R 8 SiO 2/2) y

(Wherein R ⁶ , R ⁷ , and R ⁸ are as defined in Formula 2 and 0 <x <1, 0 <y <1, x + y = 1).

<Formula 2-4>

^{_{(R 6 SiO 3/2) x (}} SiO 4/2) w

(In Formula 2-4, R ⁶ is as defined in Formula 2 and 0 <x <1, 0 <w <1, x + w = 1).

<Formula 2-5>

(R ⁶ SiO _3/2 ) _x (R ⁷ R ⁸ SiO _2/2 ) _y (SiO _4/2 ) _w

(In the above formula ^{2-5, R 6, R 7,} R 8 are as defined in Formula 2, 0 <x <1, 0 <y <1, 0 <w <1, x + y + w = 1 ).

X1 < 1, 0 < x2 < 0.20, . In the formula (2-2), 0.30? X1 <1.0, 0 <x2? 0.50, 0 <w? 0.40 More specifically, 0.40? X1 <1.0, 0 <x2? 0.40, 0? W? x1? 0.95, 0.01? x2? 0.40, and 0.01? w? 0.20. 0.70? X? 1, 0? Y? 0.30, more specifically 0.85? X? 0.99, and 0.01? Y? 0.15 in the formula (2-3) . In the formula 2-4, 0.60? X <1, 0 <y? 0.40, specifically 0.70? X <1, 0 <y? 0.30, more specifically 0.80? X? 0.99 and 0.01? Y? . 0.20? X <1.0, 0? Y? 0.60, 0? W? 0.40, x? 0.95, 0.04? y? 0.40, and 0.01? w? Within this range, flexibility and hardness of the window film can be improved and the impact resistance can be improved. In the formula 2-1, 2-2 R ^6a are the epoxidized to C4 may be a C1 to C20 alkyl group having a cycloalkyl group of C20, R ^6b is having a glycidyl group or glycidyl sidok group, C1 to C20 Alkyl group.

More specifically, the second silicone resin may be represented by the following general formulas (2-1-1) and (2-1-2):

&Lt; Formula (2-1-1)

(EcSiO3 / ₂ ) _x1 (GpSiO3 / ₂ ) _x2

(0? X1 <1, 0? X2 <1, x1 + x2 = 1, x1 + x2? 0).

<Formula 2-1-2>

(EcSiO3 / ₂ ) _x1 (GpSiO3 / ₂ ) _x2 (SiO4 / ₂ ) _w

(0 <x1 <1, 0 <x2 <1, 0 <w <1, x1 + x2 + w = 1 in the formula 2-1-2).

The second silicone resin may have a weight average molecular weight of from 2,000 g / mol to 50,000 g / mol, specifically from 2,000 g / mol to 30,000 g / mol, more specifically from 4,000 g / mol to 15,000 g / mol. The effect of supporting the coating layer of the window film in the above range may be obtained. The second silicone resin may have a polydispersity index (PDI) of 1.0 to 10. Within the above range, coating properties of the composition are good and coating properties may be stable.

The first silicone resin and the second silicone resin in the curable resin, which is the sum of the first silicone resin and the second silicone resin, may be included in an amount of 5 wt% to 80 wt% and 20 wt% to 95 wt%, respectively. Within this range, flexibility and hardness of the window film can be improved. Preferably, the first silicone resin may comprise from 50% to 80% by weight, and the second silicone resin may comprise from 20% to 50% by weight. Within this range, flexibility and hardness of the window film can be improved, and the impact resistance can be improved.

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

1, a flexible window film 100 according to an exemplary embodiment of the present invention includes a base layer 110 and a coating layer 120, And the like.

The substrate layer 110 supports the flexible window film 100 and the coating layer 120 to increase the mechanical strength of the flexible window film 100. The base layer 110 may be adhered to a display portion, a touch screen panel, or a polarizing plate by an adhesive layer or the like.

The substrate layer 110 may be formed of an optically transparent and flexible resin. For example, the resin includes a polyester resin including a polyethylene terephthalate, a polyethylene naphthalate, a polybutylene terephthalate, a polybutylene naphthalate, etc., a polycarbonate resin, a polyimide resin, a polystyrene resin, polymethylmethacrylate A poly (meth) acrylate resin, and a cycloolefin polymer resin. The resin may be contained in the base layer 110 alone or in combination.

The base layer 110 may have a thickness of 10 占 퐉 to 200 占 퐉, specifically, 20 占 퐉 to 150 占 퐉, more specifically, 50 占 퐉 to 100 占 퐉. Can be used in the flexible window film in the above range.

The coating layer 120 is formed on the base layer 110 to protect the base layer 110, the display portion, the touch screen panel or the polarizing plate, improve the appearance, have high flexibility and high hardness and can be used in a flexible display device can do. The thickness of the coating layer 120 may be 5 占 퐉 to 100 占 퐉, specifically 10 占 퐉 to 80 占 퐉. Can be used in the flexible window film in the above range. Although not shown in FIG. 1, a functional surface layer such as an antireflection layer, an antiglare layer, or a hard coating layer may be further formed on the other surface of the coating layer 120 to provide additional functions to the flexible window film. 1, a coating layer 120 may be further formed on the other surface of the substrate layer 110. [

The flexible window film 100 may have a light transmittance of 85% or more and specifically 88% to 100% in a visible light region specifically at a wavelength of 400 nm to 800 nm. It can be used as a flexible window film in the above range. The flexible window film 100 may have a pencil hardness of 4H or more, a radius of curvature of 2.0 mm or less, and an impact resistance of 40 mm or more. In the above range, the film can be used as a flexible window film with good hardness and flexibility. Specifically, the flexible window film 100 may have a pencil hardness of 4H to 9H, a radius of curvature of 0.1 mm to 2.0 mm, an impact resistance of 45 mm or more, and 45 mm to 100 mm. The flexible window film 100 may have a thickness of 5 占 퐉 to 300 占 퐉. It can be used as a flexible window film in the above range. The impact resistance of the flexible window film 100 may be 45 mm or more when the following PEN DROP TEST is used. In this range, it is possible to prevent the panel from being damaged when mounted on the OLED panel. The OLED panel may include an OELD panel commonly used by those skilled in the art.

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

2, the flexible window film 200 according to another embodiment of the present invention includes a flexible window film 200 according to an exemplary embodiment of the present invention, except that an adhesive layer 130 is further formed on the other surface of the substrate layer 110. As shown in FIG. Is substantially the same as the flexible window film (100). The adhesive layer 130 is further formed on the other surface of the base layer 110, so that adhesion between the flexible window film and the touch screen panel, the polarizing plate, or the display portion can be facilitated. Is substantially the same as the flexible window film according to an embodiment of the present invention, except that an adhesive layer is further formed. Hereinafter, only the adhesive layer 130 will be described.

The adhesive layer 130 adheres to a polarizing plate, a touch screen panel, or a display unit that can be disposed under the flexible window film 200, and may be formed of a composition for a pressure-sensitive adhesive layer.

In one embodiment, the adhesive layer 130 may be formed of a composition for a pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive resin such as a (meth) acrylic resin, a urethane resin, a silicone resin, and an epoxy resin, a curing agent, a photoinitiator and a silane coupling agent.

The (meth) acrylic resin is a (meth) acrylic copolymer having an alkyl group, a hydroxyl group, an aromatic group, a carboxylic acid group, an alicyclic group, a heteroalicyclic group, or the like and may include a conventional (meth) acrylic copolymer. Specifically, a (meth) acrylic monomer having an unsubstituted C1 to C10 alkyl group, a (meth) acrylic monomer having a C1 to C10 alkyl group having at least one hydroxyl group, a (meth) acrylic monomer having an C6 to C20 aromatic group (Meth) acrylic monomer having a carboxylic acid group, a (meth) acrylic monomer having a C3 to C20 alicyclic group, a C3 to C10 heteroalicyclic group having at least one of nitrogen (N), oxygen (O) (Meth) acryl-based monomer having at least one group selected from the group consisting of (meth) acryl-based monomers.

The curing agent may be a bifunctional (meth) acrylate such as hexanediol diacrylate as a polyfunctional (meth) acrylate; Trifunctional (meth) acrylates of trimethylolpropane tri (meth) acrylate; Tetrafunctional (meth) acrylates such as pentaerythritol tetra (meth) acrylate; Pentafunctional (meth) acrylates such as dipentaerythritol penta (meth) acrylate; (Meth) acrylate such as dipentaerythritol hexa (meth) acrylate, but are not limited thereto.

The photoinitiator may include the above-described photoinitiator as a conventional photoinitiator.

The silane coupling agent may include a silane coupling agent having an epoxy group such as 3-glycidoxypropyltrimethoxysilane and the like.

The composition for the adhesive layer may comprise 100 parts by weight of a (meth) acrylic resin, 0.1 to 30 parts by weight of a curing agent, 0.1 to 10 parts by weight of a photoinitiator, and 0.1 to 20 parts by weight of a silane coupling agent. Within this range, the flexible window film can be adhered well onto the display portion, the touch screen panel or the polarizing plate.

In another embodiment, the adhesive layer 130 may be the adhesive layer 110c described below.

The thickness of the adhesive layer 130 may be 10 占 퐉 to 100 占 퐉. In the above range, the optical element such as the flexible window film and the polarizing plate can be sufficiently adhered.

Hereinafter, a window film according to another embodiment of the present invention will be described with reference to FIG. 3 is a cross-sectional view of a window film according to another embodiment of the present invention.

3, the flexible window film 150 is substantially the same as the flexible window film 100 according to the present embodiment, except that it includes a base layer 110A instead of the base layer 110 .

The base layer 110A includes a first film 110a, a second film 110b and an adhesive layer 110c formed between the first film 110a and the second film 110b. By including the base layer 110A, the flexibility of the flexible window film can be improved and the impact resistance of the flexible window film 100 including the base layer 110 can be further improved.

The first film 110a and the second film 110b may support the flexible window film 150, respectively. The first film 110a and the second film 110b may be formed of the optically transparent and flexible resin, respectively. The first film 110a and the second film 110b may be formed of the same or different resins. For example, the first film 110a and the second film 110b may be formed of at least one of a polyester resin, a polycarbonate resin, a polyimide resin, a poly (meth) acrylate resin, and a cyclic olefin polymer resin, respectively Film.

The first film 110a and the second film 110b may have different thicknesses or the same thickness. Each of the first film 110a and the second film 110b may have a thickness of 10 mu m to 100 mu m, preferably 30 mu m to 50 mu m. Within the above range, there can be obtained an effect of excellent flexibility and impact resistance.

The base layer 110A may have a thickness of 10 mu m to 275 mu m, specifically 20 mu m to 200 mu m, more specifically 50 mu m to 110 mu m. Can be used in the flexible window film in the above range.

3 shows a case where the coating layer 120 is directly formed on the second film 110b. In the case where the coating layer 120 is formed directly on the first film 110a, that is, when the second film 110b, 110c, the first film 110a, and the coating layer 120 may be sequentially formed.

The adhesive layer 110c may be formed between the first film 110a and the second film 110b to adhere them to each other. The adhesive layer 110c can improve the bending reliability at the time of repeated folding of the window film and can increase the impact strength of the window film.

The adhesive layer 110c may have a modulus of 10 kPa to 1000 kPa at 25 占 폚. In this range, the impact resistance of the window film can be increased, and reliability can be improved even at one time or repeated folding of the window film at room temperature. Preferably, the adhesive layer 120 may have a modulus of 10 kPa to 800 kPa at 25 占 폚.

The adhesive layer 110c may have a modulus of 10 kPa to 1000 kPa at 80 캜. In the above range, the impact resistance of the window film can be increased, and reliability can be improved even when the window film is once or repeatedly folded at high temperature and high humidity. Preferably, the adhesive layer 110c may have a modulus of 10 kPa to 800 kPa at 80 占 폚.

The adhesive layer 110c may have a modulus of 10 kPa to 1000 kPa at -20 캜. Within the above range, the impact resistance of the window film can be increased, and reliability can be improved even at one time or repeated folding of the window film at a low temperature. Preferably, the adhesive layer 110c may have a modulus of 10 kPa to 500 kPa at -20 캜.

The adhesive layer 110c may have a modulus at 25 ° C of modulus: -20 ° C of 1: 1 to 1: 4, specifically 1: 1 to 1: 3.5, more specifically 1: 1 to 1: have. In the above-mentioned range, the pressure-sensitive adhesive layer has less change in physical properties with temperature change over a wide temperature range (-20 ° C to 25 ° C), so stress of the adhesive agent is reduced and no peeling or bubbling occurs in the foldable test It can be used for flexible optical members.

The adhesive layer 110c may have a modulus at a modulus of -20 deg. C at 80 deg. C of from 1: 1 to 1:10, specifically from 1: 1 to 1: 8, more specifically from 1: 1 to 1: 5 have. In the above-mentioned range, the adhesive layer does not deteriorate the adhesiveness between the adherends in a wide temperature range (-20 DEG C to 80 DEG C) and can be used for a flexible optical member.

The thickness of the adhesive layer 110c may be 10 占 퐉 to 75 占 퐉. Within the above range, there can be obtained an effect of excellent flexibility and impact resistance. Preferably, the thickness of the adhesive layer 110c may be 10 占 퐉 to 50 占 퐉 and 10 占 퐉 to 30 占 퐉.

The adhesive layer 110c may have a haze of 5% or less, specifically 3% or less, more specifically 1% or less, in the visible light region at a thickness of 100 占 퐉. In the above-mentioned range, when the adhesive layer is used in an optical display device, it exhibits excellent transparency.

The adhesive layer 110c may have a glass transition temperature (Tg) of 0 ° C or lower, for example, -150 ° C to 0 ° C, specifically -150 ° C to -20 ° C, more specifically -150 ° C to -30 ° C have. In the above-mentioned range, the pressure-sensitive adhesive layer is excellent in viscoelastic properties at low temperature and at room temperature.

The adhesive layer 110c may be formed of a transparent clear adhesive (OCA). The adhesive layer 110c is a monomer mixture for a (meth) acrylic copolymer having a hydroxyl group; Initiator; And a composition for a pressure-sensitive adhesive layer containing at least one of macromonomer and organic nanoparticles. The monomer mixture may be contained in the pressure-sensitive adhesive composition in the state of a monomer mixture in which polymerization is not carried out at all, but the monomer mixture may be contained as a partially polymerized partial polymer. Preferably, the composition for a pressure-sensitive adhesive layer comprises a monomer mixture for a (meth) acrylic copolymer having a hydroxyl group; Initiator; And organic nanoparticles.

The monomer mixture may be composed of a hydroxyl group-containing (meth) acrylate and an alkyl group-containing (meth) acrylate.

The hydroxyl group-containing (meth) acrylate can provide the adhesion of the adhesive layer. The hydroxyl group-containing (meth) acrylate may be a (meth) acrylate containing at least one hydroxyl group. For example, the hydroxyl group-containing (meth) acrylate may be at least one selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) (Meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, (Meth) acrylate, diethylene glycol mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (Meth) acrylate, trimethylolethane di (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4- Hydroxycyclopentyl (meth) acrylate (Meth) acrylate, cyclohexanedimethanol mono (meth) acrylate, and the like. The hydroxyl group-containing (meth) acrylate is used in an amount of 5 wt% to 40 wt%, such as 8 wt% to 30 wt%, 10 wt% to 30 wt% of the total of the hydroxyl group-containing (meth) acrylate and alkyl group- % &Lt; / RTI &gt; by weight. The adhesive strength and endurance reliability of the adhesive layer in the above range can be further improved.

The alkyl group-containing (meth) acrylate may become a copolymer to form a matrix of an adhesive layer. The alkyl group-containing (meth) acrylate may include an unsubstituted linear or branched alkyl (meth) acrylate having 1 to 20 carbon atoms. (Meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, (Meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, ethylhexyl (meth) acrylate, octyl (Meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, and isobonyl (meth) acrylate. The alkyl group-containing (meth) acrylate is used in an amount of 60 to 95% by weight, such as 65 to 92% by weight, 68 to 90% by weight, based on the total of the hydroxyl group-containing (meth) acrylate and alkyl group- By weight, and 70% by weight to 90% by weight. The adhesive strength and endurance reliability of the adhesive layer in the above range can be further improved.

The monomer mixture may further comprise copolymerizable monomers. The copolymerizable monomer may be contained in the (meth) acrylic copolymer to provide additional effects to the (meth) acrylic copolymer, the pressure sensitive adhesive composition or the pressure sensitive adhesive layer. The copolymerizable monomer is a monomer having an ethylene oxide, a monomer having propylene oxide, a monomer having an amine group, a monomer having an alkoxy group, a monomer having a phosphoric acid group, or a monomer having an alkyl group (meth) , A monomer having a sulfonic acid group, a monomer having a phenyl group, a monomer having a silane group, a monomer having a carboxylic acid group, and an amide group-containing (meth) acrylate.

As the monomer having an ethylene oxide, one or more (meth) acrylate monomers containing an ethylene oxide group (-CH ₂ CH ₂ O-) may be used. (Meth) acrylate, polyethylene oxide monoethyl ether (meth) acrylate, polyethylene oxide monopropyl ether (meth) acrylate, polyethylene oxide monobutyl ether (meth) acrylate, polyethylene oxide mono (Meth) acrylate, polyethylene oxide monoisobutyl ether (meth) acrylate, polyethylene oxide diethyl ether (meth) acrylate, polyethylene oxide monoisopropyl ether (meth) acrylate, polyethylene oxide monoisobutyl ether (Meth) acrylate such as polyethylene oxide mono-t-butyl ether (meth) acrylate, but is not limited thereto.

The monomer having propylene oxide is at least one monomer selected from the group consisting of polypropylene oxide monomethyl ether (meth) acrylate, polypropylene oxide monoethyl ether (meth) acrylate, polypropylene oxide monopropyl ether (meth) acrylate, polypropylene oxide monobutyl ether (Meth) acrylate, polypropylene oxide diethyl ether (meth) acrylate, polypropylene oxide monoisopropyl ether (meth) acrylate, polypropylene oxide dimethyl ether (Meth) acrylate such as polypropylene oxide monoisobutyl ether (meth) acrylate, polypropylene oxide mono butyl ether (meth) acrylate, and the like, but is not limited thereto no All.

The monomer having an amine group may be selected from monomethylaminoethyl (meth) acrylate, monoethylaminoethyl (meth) acrylate, monomethylaminopropyl (meth) acrylate, monoethylaminopropyl (meth) acrylate, dimethylaminoethyl (Meth) acrylate such as diethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, N-tert- butylaminoethyl (meth) acrylate and (meth) acryloxyethyltrimethylammonium chloride Acrylic monomer, but is not limited thereto.

Examples of the monomer having an alkoxy group include 2-methoxyethyl (meth) acrylate, 2-methoxypropyl (meth) acrylate, 2-ethoxypropyl (meth) (Meth) acrylate, methoxypentyl (meth) acrylate, 3-ethoxypentyl (meth) acrylate, 2-ethoxypentyl ) Acrylate, 3-butoxyhexyl (meth) acrylate, and the like.

Monomers having a phosphoric acid group include monomers such as 2-methacryloyloxyethyldiphenyl phosphate (meth) acrylate, trimethacryloyloxyethylphosphate (meth) acrylate, triacryloyloxyethylphosphate (meth) Acrylic monomer having a phosphoric acid group, but the present invention is not limited thereto.

The monomer having a sulfonic acid group may be an acrylic monomer having a sulfonic acid group such as sodium sulfopropyl (meth) acrylate, sodium 2-sulfoethyl (meth) acrylate, and sodium 2-acrylamido-2-methylpropane sulfonate But is not necessarily limited thereto.

The monomer having a phenyl group can be an acrylic vinyl monomer having a phenyl group such as p-tert-butylphenyl (meth) acrylate, o-biphenyl (meth) acrylate and phenoxyethyl (meth) acrylate, It is not.

The monomer having a silane group may be selected from the group consisting of 2-acetoacetoxyethyl (meth) acrylate, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethyl) silane, vinyltriacetoxysilane, Butoxypropyltrimethoxysilane, and the like, but is not limited thereto.

The monomer having a carboxylic acid group may be at least one monomer selected from the group consisting of (meth) acrylic acid, 2-carboxyethyl (meth) acrylate, 3-carboxypropyl (meth) acrylate, 4-carboxybutyl (meth) acrylate, itaconic acid, Maleic anhydride, and the like, but are not necessarily limited thereto.

The amide group-containing (meth) acrylate is at least one compound selected from the group consisting of (meth) acrylamide, N-methyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (Meth) acrylamide, N-hydroxyethyl (meth) acrylamide and N, N-diethyl (meth) acrylamide.

The copolymerizable monomer is contained in an amount of not more than 15 parts by weight, specifically not more than 10 parts by weight, more specifically 0.05 to 8 parts by weight, based on 100 parts by weight of the sum of the hydroxyl group-containing (meth) acrylate and alkyl group-containing (meth) . In the above range, the pressure-sensitive adhesive composition can further improve the adhesive force and the recoverability of the pressure-sensitive adhesive film.

Initiators can be used to cure (partially polymerize) the monomer mixture into a (meth) acrylic copolymer or to cure a viscous liquid into a film. The initiator may include at least one of a photopolymerization initiator and a thermal polymerization initiator. As the photopolymerization initiator, any photopolymerization initiator can be used as long as it can induce the polymerization reaction of the radical polymerizable compound described below in a curing process by light irradiation or the like. For example, benzoin, hydroxy ketone, amino ketone or phosphine oxide photoinitiators can be used. Specific examples thereof include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethyl anino acetophenone, 2,2- 2-methyl-1-phenylpropane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone , p-phenylbenzophenone, 4,4 non-cydiethylaminobenzophenone, dichlorobenzophenone, 2-methyl anthraquinone, 2-ethyl anthraquinone, 2-t-butyl anthraquinone, 2- Thioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal, acetophenone dimethylketal, p-dimethylaminobenzoate , Hitting [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propane paddy] and 2,4,6-trimethylbenzoyl-phosphine oxide, etc. may be mentioned - diphenyl. The thermal polymerization initiator is not particularly limited as long as it has the above-mentioned physical properties, and for example, ordinary initiators such as an azo-based compound, a peroxide-based compound or a redox-based compound can be used. Examples of the azo compound include 2,2-azobis (2-methylbutyronitrile), 2,2-triyl azo bis (isobutyronitrile), 2,2-triazabis 2-methyl azo bis (2-methylpropionate) and 2,2-phylazobis (4- (4-methoxyphenyl) Methoxy-2,4-dimethylvaleronitrile), and the like, and examples of the peroxide compound include inorganic peroxides such as potassium persulfate, ammonium persulfate or hydrogen peroxide; Or peroxydicarbonate, peroxydicarbonate, peroxy ester, tetramethyl butyl peroxyneodecanoate, bis (4-butylcyclohexyl) peroxydicarbonate, di (2-ethylhexyl) peroxycarbonate, Hexyl peroxy dicarbonate, dimethoxy butyl peroxy dicarbonate, hexyl peroxy dicarbonate, hexyl peroxy dicarbonate, diisopropyl peroxy dicarbonate, diethoxy ethyl peroxy dicarbonate, diethoxyhexyl peroxy dicarbonate, , Bis (3-methoxy-3-methoxybutyl) peroxy dicarbonate, dibutyl peroxy dicarbonate, dicetyl peroxy dicarbonate, dimyristyl peroxy dicarbonate, 1,1 , 3,3-tetramethylbutyl peroxypivalate, hexyl peroxypivalate, butyl peroxypivalate, trimethylhexanoyl peroxide, dimethylhydroxybutyl peroxy Amyl peroxyneodecanoate, t-butyl peroxyneoheptanoate, amyl peroxy pivalate, t-butyl peroxy pivalate, t-amyl peroxide, Organic peroxides such as peroxy-2-ethylhexanoate, lauryl peroxide, dilauroyl peroxide, didecanoyl peroxide, benzoyl peroxide or dibenzoyl peroxide, Examples of the system compound include, but are not limited to, a mixture of a peroxide compound and a reducing agent in combination.

The initiator is used in an amount of 0.0001 to 5 parts by weight, specifically 0.001 to 3 parts by weight per 100 parts by weight of the sum of the hydroxyl group-containing (meth) acrylate and alkyl group-containing (meth) acrylate constituting the (meth) . In the above range, the curing reaction can be completely carried out, and the remaining amount of the initiator remains, the permeability can be prevented from being lowered, the bubble generation can be lowered, and the reactivity can be improved.

The macromonomer may have a functional group curable by an active energy ray and may be polymerized with a hydroxyl group-containing (meth) acrylate and an alkyl group-containing (meth) acrylate. Specifically, the macromonomer may be represented by the following formula (3): &lt; EMI ID =

(3)

(In Formula 3, R ₁ is hydrogen or a methyl group, X represents a single bond or a divalent coupler, Y is methyl (meth) acrylate, ethyl (meth) acrylate, n- butyl (meth) acrylate, iso- butyl (Meth) acrylate, t-butyl (meth) acrylate, styrene, and (meth) acrylonitrile.

The macromonomer may have a horizontal molecular weight of 2,000 to 20,000, specifically 2,000 to 10,000, more specifically 4,000 to 8,000. Within the above range, sufficient adhesive strength can be obtained, heat resistance is excellent, and deterioration of workability due to an increase in viscosity of the pressure-sensitive adhesive composition can be suppressed. The macromonomer may have a glass transition temperature of from 40 캜 to 150 캜, specifically from 60 캜 to 140 캜, more specifically from 80 캜 to 130 캜. In this range, the pressure-sensitive adhesive layer can exhibit a sufficient cohesive force, and can suppress the degree of stickiness and deterioration of the adhesive force.

2 the coupler is an arylene group, -NR a C1 to C10 alkyl groups, C7 to C13 aryl alkyl group, C6 to C12 ² - (wherein, R ² is an alkyl group of hydrogen, or a C1 to C5), COO-, - _{O-, -S-, -SO 2 NH-,} -NHSO 2 -, may be a group derived from -NHCOO-, -OCONH, or heterocyclic.

The divalent linking group may be represented by the following formulas (3a) to (3d):

&Lt; EMI ID =

&Lt; EMI ID =

&Lt; Formula 3c >

<Formula 3d>

(In the above-mentioned formulas (3a) to (3d), * denotes the connecting site of the element)

Commercial macromonomers may be used. For example, a macromonomer wherein the terminal is methacryloyl group and the segment corresponding to Y is methyl methacrylate, the segment corresponding to Y is styrene, the segment corresponding to Y is a styrene / acryl Macromonomers in which the segment corresponding to Y is butyl acrylate, and the like can be used.

The macromonomer is used in an amount of 20 parts by weight or less, specifically 0.1 part by weight to 20 parts by weight, 0.1 part by weight to 10 parts by weight, 0.5 part by weight (meth) acrylate based on 100 parts by weight of the sum of the hydroxyl group-containing (meth) To 5 parts by weight. Within the above range, the viscoelasticity of the adhesive layer can be balanced with the modulus and the restoring force, and the increase in haze of the adhesive layer can be prevented.

The average particle diameter of the organic nanoparticles may be 10 nm to 400 nm, specifically 10 nm to 300 nm, more specifically 30 nm to 280 nm, more specifically 50 nm to 280 nm. In the above range, the transparency of the adhesive layer may be good with the total light transmittance of not less than 90% in the visible light region without affecting the folding of the adhesive layer.

The refractive index difference between the organic nanoparticles and the (meth) acrylic copolymer having a hydroxyl group may be 0.1 or less, specifically 0 or more and 0.05 or less, specifically 0 or more and 0.02 or less. In the above range, the transparency of the adhesive layer can be excellent. The refractive index of the organic nanoparticles may be 1.35 to 1.70, specifically 1.40 to 1.60. Within this range, the transparency of the adhesive layer may be excellent.

The organic nanoparticles may include, but are not limited to, core-shell type and simple nanoparticles such as a bead type. In the case of a core-shell type, the core and the shell may satisfy the following formula 1: that is, both the core and the shell may be nanoparticles that are organic materials. When the above-mentioned particle form is used, the adhesive property of the adhesive layer is good, and the balance property of elasticity and flexibility can be effective.

<Formula 1>

Tg (c) < Tg (s)

(Unit: 占 폚), and Tg (s) is the glass transition temperature (unit: 占 폚) of the shell.

As used herein, the term " shell " means the outermost layer of the organic nanoparticles. The core may be a single spherical particle. However, the core may further comprise additional layers surrounding the spherical particles if they have the above glass transition temperature.

Specifically, the glass transition temperature of the core may be -150 ° C to 10 ° C, specifically -150 ° C to -5 ° C, more specifically -150 ° C to -20 ° C. Within this range, there may be a low temperature and / or room temperature viscoelastic effect of the adhesive layer. The core may contain at least one of polyalkyl (meth) acrylate, polysiloxane or polybutadiene having the above glass transition temperature.

The polyalkyl (meth) acrylate may be at least one selected from the group consisting of polymethyl acrylate, polyethylacrylate, polypropyl acrylate, polybutyl acrylate, polyisopropyl acrylate, polyhexyl acrylate, polyhexyl methacrylate, polyethylhexyl acrylate And polyethylhexyl methacrylate, polysiloxane, and is not necessarily limited thereto.

The polysiloxane can be, for example, an organosiloxane (co) polymer. The organosiloxane (co) polymer may be one which is not cross-linked, or a cross-linked (co) polymer may be used. In order to impart impact resistance and colorability, an organosiloxane (co) polymer in a crosslinked state can be used. It is a crosslinked form of organosiloxane, specifically crosslinked dimethylsiloxane, methylphenylsiloxane, diphenylsiloxane or a mixture of two or more thereof. By using a copolymerized form of two or more organosiloxanes, the refractive index can be adjusted from 1.41 to 1.50.

The crosslinking state of the organosiloxane (co) polymer can be determined by the degree of dissolution by various organic solvents. As the crosslinking state deepens, the degree of dissolution by the solvent becomes smaller. As the solvent for determining the crosslinking state, acetone, toluene and the like can be used. Specifically, the organosiloxane (co) polymer may have a portion which is not dissolved by acetone or toluene. The insoluble matter to the toluene of the organosiloxane copolymer may be 30% or more.

Additionally, the organosiloxane (co) polymer may further comprise an alkyl acrylate crosspolymer. The alkyl acrylate crosslinked polymer may be selected from the group consisting of methyl acrylate, ethyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate. For example, n-butyl acrylate or 2-ethylhexyl acrylate having a low glass transition temperature may be used.

Specifically, the glass transition temperature of the shell may be from 15 캜 to 150 캜, specifically from 35 캜 to 150 캜, more specifically from 50 캜 to 140 캜. In the above range, the dispersibility of the organic nanoparticles in the (meth) acrylic copolymer may be excellent. The shell may comprise a polyalkyl methacrylate having said glass transition temperature. For example, it is possible to use polymethylmethacrylate (PMMA), polyethylmethacrylate, polypropylmethacrylate, polybutylmethacrylate, polyisopropylmethacrylate, polyisobutylmethacrylate and polycyclohexylmethacrylate Rate, &lt; / RTI &gt; but is not necessarily limited thereto.

The core may comprise from 30 wt% to 99 wt%, specifically from 40 wt% to 95 wt%, and more specifically from 50 wt% to 90 wt%, of the organic nanoparticles. Within the above range, the folding property of the adhesive layer may be good in a wide temperature range. The shell may comprise from 1 wt% to 70 wt%, specifically from 5 wt% to 60 wt%, more specifically from 10 wt% to 50 wt%, of the organic nanoparticles. Within the above range, the folding property of the adhesive layer may be good in a wide temperature range.

The organic nanoparticles are added in an amount of 0.1 part by weight to 20 parts by weight, specifically 0.5 part by weight to 10 parts by weight, specifically 0.5 part by weight to 100 parts by weight, based on 100 parts by weight of the sum of the hydroxyl group-containing (meth) acrylate and alkyl group- 8 parts by weight. Within the above range, the modulus of the pressure-sensitive adhesive layer at high temperature can be increased, the folding property of the pressure-sensitive adhesive layer at room temperature and high temperature can be improved, and the low temperature and / or room temperature viscoelasticity of the pressure-

The organic nanoparticles can be prepared by conventional emulsion polymerization, suspension polymerization, or solution polymerization.

The adhesive layer composition may further comprise a silane coupling agent. As the silane coupling agent, those conventionally known to those skilled in the art can be used. For example, there can be mentioned 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl tri A silicon compound having an epoxy structure such as methoxysilane; A polymerizable unsaturated group-containing silicon compound such as vinyltrimethoxysilane, vinyltriethoxysilane and (meth) acryloxypropyltrimethoxysilane; Containing silicon compounds such as 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane. ; And 3-chloropropyltrimethoxysilane, and the like, but are not limited thereto. The silane coupling agent may be contained in an amount of 0.01 to 3 parts by weight, specifically 0.01 to 1 part by weight, based on 100 parts by weight of the sum of the hydroxyl group-containing (meth) acrylate and alkyl group-containing (meth) acrylate. In the above range, reliability can be secured in the bending state at the high temperature and high humidity described above, and the difference in peeling force between low temperature, normal temperature and high temperature can be low.

The composition for a pressure-sensitive adhesive layer may further comprise a crosslinking agent. The crosslinking agent can increase the degree of crosslinking of the composition for a pressure-sensitive adhesive layer to increase the mechanical strength of the pressure-sensitive adhesive layer. The crosslinking agent may be a bifunctional (meth) acrylate such as a polyfunctional (meth) acrylate capable of being cured with an active energy ray, such as hexanediol diacrylate, or a trifunctional to hexafunctional (meth) acrylate . The crosslinking agent is used in an amount of 0.001 to 5 parts by weight, specifically 0.003 to 3 parts by weight, more preferably 0.005 to 1 part by weight, based on 100 parts by weight of the sum of the hydroxyl group-containing (meth) acrylate and alkyl group- &Lt; / RTI &gt; There is an effect of excellent adhesion and reliability in the above range.

3 shows a case where the base film is a film laminate in which the first film 110a and the second film 110b are laminated by the adhesive layer 110c. However, the case where the base layer includes three or more films and at least two or more of them are laminated with each other by the adhesive layer 110c can be included in the scope of the present invention.

Hereinafter, a flexible display device according to an embodiment of the present invention will be described with reference to FIGS. 4 and 5. FIG. FIG. 4 is a cross-sectional view of a flexible display device according to an embodiment of the present invention, and FIG. 5 is a cross-sectional view of an exemplary embodiment of the display unit of FIG.

4, the flexible display device 300 includes a display portion 350a, an adhesive layer 360, a polarizing plate 370, a touch screen panel 380, and a flexible window film 390, (390) may comprise a flexible window film according to embodiments of the present invention.

The display unit 350a is for driving the flexible display device 300 and may include an optical element including an OLED, an LED, or an LCD device formed on a substrate and a substrate. 5 is a cross-sectional view according to an embodiment of the display unit of FIG. 5, the display portion 350a may include a lower substrate 310, a thin film transistor 316, an organic light emitting diode 315, a planarization layer 314, a protection layer 318, and an insulation layer 317 have.

The lower substrate 310 supports the display portion 350a and the lower substrate 310 may have a thin film transistor 316 and an organic light emitting diode 315 formed thereon. A flexible printed circuit board for driving the touch screen panel 380 may be formed on the lower substrate 310. The flexible printed circuit board may further include a timing controller for driving the organic light emitting diode array, a power supply unit, and the like.

The lower substrate 310 may include a substrate formed of a flexible resin. Specifically, the lower substrate 310 may include, but is not limited to, a flexible substrate such as a silicon substrate, a polyimide substrate, a polycarbonate substrate, and a polyacrylate substrate.

A plurality of pixel regions are defined by a plurality of driving wirings (not shown) and sensor wirings (not shown) crossing the display region of the lower substrate 310, and thin film transistors 316 and thin film transistors 316 And an organic light emitting diode (OLED) 315 connected to the organic light emitting diode array. In a non-display area of the lower substrate, a gate driver for applying an electrical signal to the driving wiring may be formed in the form of a gate in panel. The gate-in panel circuit portion may be formed on one side or both sides of the display region.

The thin film transistor 316 may be formed on the lower substrate 310 by controlling a current flowing through the semiconductor by applying an electric field perpendicular thereto. The thin film transistor 316 may include a gate electrode 310a, a gate insulating film 311, a semiconductor layer 312, a source electrode 313a, and a drain electrode 313b. The thin film transistor 316 includes an oxide thin film transistor using an oxide such as indium gallium zinc oxide (IGZO), ZnO, or TiO.sub.2 as the semiconductor layer 312, an organic thin film transistor using an organic material as a semiconductor layer, an amorphous silicon An amorphous silicon thin film transistor to be used, or a polycrystalline silicon thin film transistor using polycrystalline silicon as a semiconductor layer.

The planarization layer 314 may cover the thin film transistor 316 and the circuit portion 310b so that the top surface of the thin film transistor 316 and the circuit portion 310b may be planarized to form the organic light emitting diode 315. [ The planarization layer 314 may be formed of a spin-on-glass (SOG) film, a polyimide-based polymer, a polyacrylic polymer, or the like, but is not limited thereto.

The organic light emitting diode 315 emits light by self-emission, and may include a first electrode 315a, an organic light emitting layer 315b, and a second electrode 315c stacked in that order. The adjacent organic light emitting diodes may be separated through an insulating film 317. [ The organic light emitting diode 315 may include a bottom emission structure in which light generated in the organic emission layer 315b is emitted through the lower substrate or a top emission structure in which light generated in the organic emission layer 315b is emitted upward.

The passivation layer 318 may cover the organic light emitting diode 315 to protect the organic light emitting diode 315. The passivation layer 318 may be formed of an inorganic material such as SiOx, SiNx, SiC, SiON, SiONC, and aC (amorphous carbon) Methacrylate, epoxy-based polymer, imide-based polymer, and the like. Specifically, the protective layer 318 may include an encapsulation layer in which a layer formed of an inorganic material and a layer formed of an organic material are sequentially stacked one or more times.

Referring again to FIG. 4, the adhesive layer 360 is formed of a pressure-sensitive adhesive composition comprising a (meth) acrylate resin, a curing agent, an initiator and a silane coupling agent to adhere the display portion 350a and the polarizing plate 370 .

The polarizing plate 370 can implement polarizing of the inner light or prevent reflection of the external light to realize the display or to increase the contrast ratio of the display. The polarizing plate may be composed of a polarizer alone. Or the polarizing plate may include a polarizing film and a protective film formed on one or both sides of the polarizing film. Or the polarizing plate may include a polarizer and a protective coating layer formed on one or both sides of the polarizer. The polarizer, the protective film, and the protective coating layer may be conventional ones known to those skilled in the art.

The touch screen panel 380 senses a change in capacitance generated when a conductor such as a human body or a stylus touches, and generates an electrical signal. The display unit 350a can be driven by this signal. The touch screen panel 380 is formed by patterning a flexible conductive conductive material. The touch screen panel 380 may include a first sensor electrode and a second sensor electrode formed between the first sensor electrode and the first sensor electrode. have. The conductor for the touch screen panel 380 may include, but is not limited to, metal nanowires, conductive polymers, carbon nanotubes, and the like.

The flexible window film 390 may be formed at the outermost portion of the flexible display device 300 to protect the display device.

Although not shown in FIG. 4, an adhesive layer is further formed between the polarizer 370 and the touch screen panel 380 and / or between the touch screen panel 380 and the flexible window film 390 to form a polarizing plate, a touch screen panel, It is possible to strengthen the bonding between the window films. The pressure-sensitive adhesive layer may be formed of a pressure-sensitive adhesive composition comprising a (meth) acrylate resin, a curing agent, an initiator, and a silane coupling agent. Or the adhesive layer may be an adhesive layer containing the organic nanoparticles. Further, although not shown in FIG. 4, a polarizing plate is further provided under the display unit 350a, so that polarized light can be realized.

Hereinafter, a flexible display device according to another embodiment of the present invention will be described with reference to FIG. 6 is a cross-sectional view of a flexible display device according to another embodiment of the present invention.

6, the flexible display device 400 includes a display portion 350a, a touch screen panel 380, a polarizer 370, and a flexible window film 390, May include a flexible window film according to embodiments of the invention. Except that the touch screen panel 380 is not directly formed on the flexible window film 390 but the touch screen panel 380 is formed below the polarizer 370. In this case, Device. At this time, the touch screen panel 380 may be formed together with the display portion 350a. In this case, since the touch screen panel 380 is formed on the display unit 350a together with the display unit 350a, the thickness of the touch screen panel 380 can be thinner and brighter than that of the flexible display device according to an embodiment of the present invention. In this case, the touch screen panel 380 can be formed by deposition or the like, but is not limited thereto. Although not shown in FIG. 6, between the display portion 350a and the touch screen panel 380 and / or between the touch screen panel 380 and the polarizer 370 and / or between the polarizer 370 and the flexible window film 390 An adhesive layer is further formed, thereby increasing the mechanical strength of the display device. The pressure-sensitive adhesive layer may be formed of a pressure-sensitive adhesive composition comprising a (meth) acrylate resin, a curing agent, an initiator, and a silane coupling agent. Or the adhesive layer may be an adhesive layer containing the organic nanoparticles. Further, although not shown in FIG. 6, a polarizing plate is further provided under the display unit 350a to thereby guide polarized light to improve the display image.

Hereinafter, a flexible display device according to another embodiment of the present invention will be described with reference to FIG. 7 is a cross-sectional view of a flexible display device according to another embodiment of the present invention. 7, the flexible display device 500 includes a display portion 350b, an adhesive layer 360, and a flexible window film 390, and the flexible window film 390 includes a flexible window film 390 according to embodiments of the present invention. And may include a flexible window film. Is substantially the same as the flexible display device according to an embodiment of the present invention, except that only the display portion 350b is capable of driving the device and the polarizing plate and the touch screen panel are excluded.

The display portion 350b may include an LCD, an OLED, or an optical element including an LED element formed on the substrate, and the display portion 350b may have a touch screen panel formed therein.

Hereinafter, a method for producing the first silicone resin and the second silicone resin according to one embodiment of the present invention will be described.

The first silicone resin of the formula (I) according to this embodiment is (R ¹ SiO _3/2) providing a silicon _{^{monomer, (R 2 R 3 SiO 2}} /2) to provide a silicon monomer, the (SiO _3/2 -R ⁴ -SiO _3/2) can be prepared by the hydrolysis and condensation reaction of the silicon monomer mixture comprising a silicone monomer to give a. _{^{Specifically, (R 1 SiO 3/2}} ) to provide a silicone monomer is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl triethoxysilane , 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and the like. (R ² R ³ SiO _2/2 ) may be dimethyldimethoxysilane, dimethyldiethoxysilane, and the like, but are not limited thereto. ^{_{(SiO 3/2 -R 4 -R}} 5 -SiO 3/2) to provide a silicone monomer is 1,2-bis (triethoxysilyl) ethane, 1,4-bis (triethoxysilyl) butane, 1 (Triethoxysilyl) octane, 1,4-bis (triethoxysilyl) cyclohexane, 1,4-bis (triethoxysilyl) benzene, 1,4- ) Benzene, 1,4-bis (trimethoxysilylethyl) benzene, and the like.

In one embodiment, the monomer mixture (R ¹ SiO _3/2) silicone monomer 1mol% to about 90mol%, particularly 5mol% to 80mol%, more particularly, 10mol% to 55mol% for service, (R ² R ³ SiO _{Part 2 of 2)} the silicon monomer 1mol% to about 90mol%, specifically 10mol% to 80mol%, more particularly, 30mol% to about _{80mol%, (SiO 3/2} -R 4 -R 5 -SiO 3/2) to provide And may contain 0.5 mol% to 50 mol%, specifically 1 mol% to 40 mol%, more specifically 5 mol% to 30 mol% of silicon monomers. Within this range, the hardness, flexibility and impact resistance of the window film can be improved.

A second silicone resin according to the present embodiment (R ⁶ SiO _3/2) silicone monomer to provide a silicon monomer alone, or (R ⁶ SiO _3/2) to provide; And _{^{(R 7 R 8 SiO 2/}} 2) a silicon monomer, to provide ^{(R 9 R 10 R 11 SiO} 1/2) to provide the silicon monomer, (SiO _4/2) at least one mixture of the silicone monomers to provide for &Lt; / RTI &gt; (R ⁶ SiO _3/2) a silicon monomer is to provide a 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl triethoxysilane, 3- glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane in propyltriethoxysilane and the like can be _{^{silane, (R 7 R 8 SiO 2}} /2) to provide a silicon monomer include dimethyl dimethoxysilane, dimethyl diethoxysilane (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyltriethoxysilane and the like, and SiO _{2 / 2} ) may be, but not limited to, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and the like. In one embodiment, the monomer mixture (R ⁶ SiO _3/2) silicone monomer 100mol% which provides, in particular 85mol% to about 99mol%, 1mol% to about 15mol%, 40mol% to about 95mol%, 1mol% to about 40mol%, It can be a (SiO _4/2) silicone monomer 0mol%, 1mol% to about 20mol% to service. _{^{(R 7 R 8 SiO 2/}} 2) to provide a silicone monomer may be included to 1mol% to about 15mol%, 4mol% to 40mol%. Within this range, the hardness and flexibility of the window film can be improved.

The hydrolysis and condensation reaction of the monomer mixture can be carried out according to a conventional method for producing a silicone resin. Hydrolysis may comprise reacting the monomer mixture with water and a mixture of one or more of the desired acids and bases. Specifically, the acid may be HCl, HNO ₃ , acetic acid or the like, and the base may be NaOH, KOH, or the like. The hydrolysis is carried out at 20 ° C to 100 ° C for 10 minutes to 10 hours, and the condensation reaction can be carried out at 20 ° C to 100 ° C for 10 minutes to 12 hours under the same conditions as the hydrolysis. The production yield of the silicone resin in the above range may be high.

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

The flexible window film 100 can be manufactured by a method of manufacturing a flexible window film including coating and curing a composition for a window film according to embodiments of the present invention on a substrate layer 110. [

The method for coating the composition for a window film on the base layer 110 may be, but not limited to, bar coating, spin coating, dip coating, roll coating, flow coating, die coating and the like. A composition for a window film can be coated on the base layer 110 to a thickness of 5 to 100 mu m. It is possible to secure a desired coating layer within the above range, and to have an excellent hardness and flexibility. Curing is a process of curing the composition for a window film to form a coating layer, which may include at least one of light curing and heat curing. Photocuring may involve irradiation with light amount of 10mJ / cm ² to 1,000mJ / cm ² at a wavelength of 400nm or less. Thermal curing may include treating at 40 占 폚 to 200 占 폚 for 1 hour to 30 hours. Within this range, the composition for a window film can be sufficiently cured. For example, it is possible to photo-cure and then thermally cure, resulting in a higher hardness of the coating layer. The method may further include drying the composition for the window film before coating the composition for the window film on the substrate layer 110 and then curing the composition. By drying and curing, it is possible to prevent the surface roughness of the coating layer from becoming high due to long-time light curing and thermal curing. The drying may be performed at 40 캜 to 200 캜 for 1 minute to 30 hours, but is not limited thereto.

Hereinafter, the present invention will be described in more detail by way of examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Manufacturing example  1-1: First silicone resin

45 mol% of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Shin-Etsu), 45 mol% of dimethyldimethoxysilane (UMT), 1,2-bis (triethoxysilyl) ethane The mixture of monomers was put into a 500 mL 3-neck flask at a ratio of 10 mol%. Thereafter, 0.5 mol% of KOH catalyst and 2.85 mol% of water were added to the mixture, and the mixture was stirred at 25 ° C for 2 hours and then at 70 ° C for 6 hours. Removal of the solvent remaining in a vacuum distillation unit to the first silicone resin _{((EcSiO 3/2) 0.45} ((Me) 2 SiO 2/2) 0 .45 (SiO 3/2 -CH 2 CH 2 -SiO 3/2 ) _0.10 ). The weight average molecular weight of the first silicone resin determined by gel permeation chromatography was 17,000 g / mol.

Production Example 1-2: First silicone resin

, 45 mol% of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Shin-Etsu), 50 mol% of dimethyldimethoxysilane (UMT), 1,2-bis (triethoxysilyl) ethane The mixture of monomers was put into a 500 mL 3-neck flask at a ratio of 5 mol%. Thereafter, 0.5 mol% of KOH catalyst and 2.65 mol% of water were added to the mixture, and the mixture was stirred at 25 DEG C for 2 hours and then at 70 DEG C for 6 hours. Removal of the solvent remaining in a vacuum distillation unit to the first silicone resin _{((EcSiO 3/2) 0.45} ((Me) 2 SiO 2/2) 0 .50 (SiO 3/2 -CH 2 CH 2 -SiO 3/2 ) _0.05 ). The weight average molecular weight of the first silicone resin determined by gel permeation chromatography was 16,500 g / mol.

Production Example 1-3: First silicone resin

20 mol% of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Shin-Etsu), 70 mol% of dimethyldimethoxysilane (UMT), 1,2-bis (triethoxysilyl) ethane The mixture of monomers was put into a 500 mL 3-neck flask at a ratio of 10 mol%. Thereafter, 0.6 mol% of KOH catalyst and 2.60 mol% of water were added to the mixture, and the mixture was stirred at 25 ° C for 2 hours and then at 70 ° C for 6 hours. Removal of the solvent remaining in a vacuum distillation unit to the first silicone resin _{((EcSiO 3/2) 0.20} ((Me) 2 SiO 2/2) 0 .70 (SiO 3/2 -CH 2 CH 2 -SiO 3/2 ) _0.10 ). The weight average molecular weight of the first silicone resin determined by gel permeation chromatography was 11,400 g / mol.

Production Example 1-4: First silicone resin

20 mol% of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Shin-Etsu), 75 mol% of dimethyldimethoxysilane (UMT), 1,2-bis (triethoxysilyl) ethane The mixture of monomers was put into a 500 mL 3-neck flask at a ratio of 5 mol%. Thereafter, 0.6 mol% of KOH catalyst and 2.40 mol% of water were added to the mixture, and the mixture was stirred at 25 ° C for 2 hours and then at 70 ° C for 6 hours. Removal of the solvent remaining in a vacuum distillation unit to the first silicone resin _{((EcSiO 3/2) 0.20} ((Me) 2 SiO 2/2) 0 .75 (SiO 3/2 -CH 2 CH 2 -SiO 3/2 ) _0.05 ). The weight average molecular weight of the first silicone resin determined by gel permeation chromatography was 4,700 g / mol.

Production Example 1-5: First silicone resin

20 mol% of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (Shin-Etsu), 60 mol% of dimethyldimethoxysilane (UMT), 1,2-bis (triethoxysilyl) ethane The mixture of monomers was put into a 500 mL 3-neck flask at a ratio of 20 mol%. Then, 2 mol% of KOH catalyst and 3.0 mol% of water were added to the mixture, and the mixture was stirred at 25 DEG C for 2 hours and then at 70 DEG C for 6 hours. Removal of the solvent remaining in a vacuum distillation unit to the first silicone resin _{((EcSiO 3/2) 0.20} ((Me) 2 SiO 2/2) 0 .60 (SiO 3/2 -CH 2 CH 2 -SiO 3/2 ) _0.20 ). The weight average molecular weight of the first silicone resin determined by gel permeation chromatography was 28,000 g / mol.

Production Example 1-6: First silicone resin

, 45 mol% of 3-glycidoxypropyltrimethoxysilane (Shin-Etsu), 50 mol% of dimethyldimethoxysilane (UMT) and 5 mol% of 1,2-bis (triethoxysilyl) ethane (Aldrih) The monomer mixture was placed in a 500 mL 3-neck flask. Thereafter, 0.5 mol% of KOH catalyst and 2.65 mol% of water were added to the mixture, and the mixture was stirred at 25 DEG C for 2 hours and then at 70 DEG C for 6 hours. Removal of the solvent remaining in a vacuum distillation unit to the first silicone resin _{((GpSiO 3/2) 0.45} ((Me) 2 SiO 2/2) 0 .50 (SiO 3/2 -CH 2 CH 2 -SiO 3/2 ) _0.05 ). The weight average molecular weight of the first silicone resin determined by gel permeation chromatography was 6,100 g / mol.

Production Example 2: Second silicone resin

95 mol% of 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane (Shin-Etsu) and 5 mol% of 3-glycidoxypropyltrimethoxysilane (Shin-Etsu) were dissolved in 500 mL of 3-neck flask . Then, 0.5 mol% of KOH catalyst and 3 mol% of water were added to the mixture, and the mixture was stirred at 25 DEG C for 2 hours and then at 70 DEG C for 6 hours. Removal of the solvent remaining in a vacuum distillation apparatus to manufacture a second silicone resin _{((EcSiO 3/2) 0.95} (GpSiO 3/2) 0. 05). The weight average molecular weight of the second silicone resin determined by gel permeation chromatography was 6,000 g / mol.

Example 1

100 parts by weight of the first silicone resin of Production Example 1-1, 20 parts by weight of 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate as a crosslinking agent, 20 parts by weight of diphenyliodonium hexafluoro And 2 parts by weight of phosphate (DPI-PF6, manufactured by TCI) were mixed to prepare a composition for a window coating layer. The composition for the coating layer was applied to a PI film (polyimide film, SDI, thickness: 80 μm), dried at 60 ° C. for 4 minutes, exposed to ultraviolet light of 500 mJ / cm ² to prepare a coating film having a thickness of 50 μm , And heated in an oven at 100 DEG C for 24 hours to prepare a window film having a window coating layer thickness of 50 mu m.

Examples 2 to 6

A window film was prepared in the same manner as in Example 1, except that the kind of the first silicone resin was changed as shown in Table 1 below.

Example 7 and Example 8

A window film was prepared in the same manner as in Example 1, except that the kind of the first silicone resin, the kind of the second silicone resin, and the content of each were changed to the following Table 1 (unit: parts by weight).

Example  9

Shell structure in which the core is polybutyl acrylate (PBA) and the shell is polymethyl methacrylate (PMMA), the shell is 40 wt% of the organic particles, the average particle diameter is 230 nm, the refractive index is 1.48 Nanoparticles were prepared. 4 parts by weight of the organic nanoparticles prepared above and 100 parts by weight of a photopolymerization initiator (Irgacure 651) were added to 100 parts by weight of a monomer mixture containing 70% by weight of 2-ethylhexyl acrylate and 30% by weight of 4-hydroxybutyl acrylate Were mixed well in a glass container. The mixture was polymerized by replacing the dissolved oxygen in the glass vessel with nitrogen gas and irradiating with ultraviolet rays using a low-pressure lamp (BL Lamp manufactured by Sankyo) for several minutes to obtain a partially polymerized product having a hydroxyl group having a viscosity of about 1000 CPS Meth) acrylic copolymer was obtained. 0.35 parts by weight of an additional photopolymerization initiator (c2) (Irgacure 184) was added to the resulting (meth) acrylic copolymer having a hydroxyl group to prepare a pressure-sensitive adhesive composition. The resulting pressure-sensitive adhesive composition was coated on a release-treated PET (polyethylene terephthalate film, thickness 50 탆) to form a pressure-sensitive adhesive film having a thickness of 25 탆. A 75 mu m thick release film was covered on the upper side, and then the both sides were irradiated with a low-pressure lamp (BL Lamp manufactured by Sankyo Company) for 6 minutes to obtain a transparent pressure-sensitive adhesive sheet. The PET film was removed from the transparent pressure-sensitive adhesive sheet to obtain a pressure-sensitive adhesive layer having a thickness of 25 m.

A PET film, a pressure-sensitive adhesive layer, and a PET film were successively adhered to one surface of a polyethylene terephthalate film (PET film, thickness: 40 m) different from the surface of a polyethylene terephthalate film (PET film, thickness: A laminated film laminate having a three-layer structure was produced.

A window film was prepared in the same manner as in Example 1 except that the above-mentioned film laminate was used as a base layer.

Comparative Example 1

A window film was prepared in the same manner as in Example 1, except that 100 parts by weight of the second silicone resin of Production Example 2 was used instead of 100 parts by weight of the first silicone resin of Production Example 1-1.

The following properties (1) to (3) of the window films prepared in Examples and Comparative Examples were measured and shown in Table 1 below.

(1) Pencil hardness: Measured by the JIS K5400 method using a pencil hardness meter (Heidon) for the coating layer of the window film. In the pencil hardness measurement, a pencil was used from Mitsubishi's 6B to 9H pencil. The load of the pencil on the coating layer was 1 kg, the angle of drawing the pencil was 45 °, and the drawing speed of the pencil was 60 mm / min. 5 times, and when a scratch occurs more than once, it is measured by using a pencil of the pencil hardness level, and when it is 5 times of the evaluation, it is the maximum pencil hardness value when there is no scratch.

(2) Curvature radius: A window film (width x length, 3 cm x 15 cm) was wound around a curvature radius test JIG, and the wound state was maintained for 5 seconds. At this time, the direction of the compression was measured by allowing the coating layer to contact the JIG, and the tensile direction was measured by allowing the base layer to contact the JIG. The radius of curvature was measured by decreasing the radius from the larger value to the smaller value in the compression direction. The radius of curvature was determined as the minimum radius of the JIG without cracking.

(3) Impact resistance: An adhesive film (thickness: 50 탆, 3M, OCA 8146) was attached to the window films of Examples and Comparative Examples, and the window film was laminated on a polyethylene terephthalate (PET) film (thickness: 2500 탆, Mitsubishi) The window coating layer was fixed to the top. A specimen was prepared by sequentially placing an aluminum foil and a stainless steel plate (SUS plate) on the lower surface of the PET film. The PEN DROP TEST was performed by dropping a pen having a ball size (diameter) of 0.7 mm and a weight of 5.8 g at a predetermined height from a window coating layer of the above specimen and measuring the initial height of a visible mark on the surface of the aluminum foil and window coating layer . The average value was obtained by repeating this process five times. The higher the initial height, the higher the impact resistance of the window film. In case of PEN DROP TEST, it means that even if the OLED panel is mounted when the initial height of the mark is more than 4.5cm, there is no impact.

Example Comparative Example One 2 3 4 5 6 7 8 9 One Silicone resin
(Parts by weight)





Manufacturing example
1-1 100 - - - - - - - 100 - Manufacturing example
1-2 - 100 - - - - - - - - Manufacturing example
1-3 - - 100 - - - 60 - - - Manufacturing example
1-4 - - - 100 - - - 60 - - Manufacturing example
1-5 - - - - 100 - - - - - Manufacturing example
1-6 - - - - - 100 - - - - Production Example 2 - - - - - - 40 40 - 100 Cross-linking agent
(Parts by weight) 20 20 20 20 20 20 20 20 20 20 Initiator
(Parts by weight) 2 2 2 2 2 2 2 2 2 2 The substrate layer PI film PI film PI film PI film PI film PI film PI film PI film Film laminate PI film Pencil hardness 8H 8H 7H 7H 7H 7H 8H 8H 8H 7H Radius of curvature (mm) 2 2 One One One One 2 2 2 3 Impact resistance (mm) 50 50 60 60 45 45 50 50 70 40

As shown in Table 1, the flexible window film of the present invention was excellent in impact resistance, hardness, and flexibility. Particularly, the flexible window film of Example 9 including the film laminate had the same effects as Example 1, such as pencil hardness and curvature radius, but the impact resistance was remarkably improved.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (19)

A composition for a window film comprising a curable resin, a crosslinking agent and an initiator,
Wherein the curable resin comprises a first silicone resin represented by the following formula (1): < EMI ID =
&Lt; Formula 1 &gt;
(R ¹ SiO _3/2 ) _x (R ² R ³ SiO _2/2 ) _y (SiO _3/2 -R ⁴ -R ⁵ -SiO _3/2 ) _z
Wherein R ¹ is an epoxy group, an epoxy group-containing functional group, a (meth) acrylate group, a (meth) acrylate group-containing functional group, an oxetane group or an oxetane group-
R ² and R ³ are each independently a hydrogen atom or a substituted or unsubstituted C1 to C12 alkyl group,
R ⁴ is a single bond, a substituted or unsubstituted C1 to C16 alkylene group, a substituted or unsubstituted C6 to C20 cycloalkylene group, or a substituted or unsubstituted C6 to C20 arylene group,
R ⁵ is a single bond, a substituted or unsubstituted C 1 to C 16 alkylene group, a substituted or unsubstituted C 6 to C 20 arylene group, a substituted or unsubstituted C 6 to C 20 cycloalkylene group, a substituted or unsubstituted C 7 to C - (- OR ^a -) n- (wherein R ^a is a substituted or unsubstituted C1 to C5 alkylene group, and n is an integer of 1 to 5)
0 <x <1, 0 <y <1, 0 <z <1, x + y + z = 1).
2. The composition for a window film according to claim 1, wherein 0.10? X? 0.55, 0.30? Y? 0.80, 0.05? Z? 0.30, and x + y + z =
The composition for a window film according to claim 1, wherein the first silicone resin of Formula 1 is represented by any one of the following Formulas 1-1 to 1-8:
&Lt; Formula 1-1 >
(EcSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z
(1-2)
(GpSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z
<Formula 1-3>
(EcSiO _3/2 ) _x ((Et) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z
<Formula 1-4>
(GpSiO _3/2 ) _x ((Et) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ -SiO _3/2 ) _z
&Lt; Formula 1-5 >
(EcSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ CH ₂ -SiO _3/2 ) _z
<Formula 1-6>
(GpSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ CH ₂ -SiO _3/2 ) _z
<Formula 1-7>
(EcSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ - (-OCH ₂ CH ₂ -) n -SiO _3/2 ) _z
&Lt; Formula (1-8)
(GpSiO _3/2 ) _x ((Me) ₂ SiO _2/2 ) _y (SiO _3/2 -CH ₂ CH ₂ - (-OCH ₂ CH ₂ -) n -SiO _3/2 ) _z
(Wherein, Ec represents a 2- (3,4-epoxycyclohexyl) ethyl group, Gp represents a 3-glycidoxypropyl group, Me represents a methyl group, Et represents an ethyl group, 0 <x <1, 0 <y < 0 < z < 1, x + y + z = 1 and n is an integer of 1 to 5).
The composition for a window film according to claim 1, wherein the curable resin further comprises a second silicone resin of the following formula (2): < EMI ID =
(2)
(R ⁶ SiO _3/2 ) _x (R ⁷ R ⁸ SiO _2/2 ) _y (R ⁹ R ¹⁰ R ¹¹ SiO _1/2 ) _z (SiO _4/2 ) _w
(Wherein R ⁶ represents an epoxy group, an epoxy group-containing functional group, a (meth) acrylate group, a (meth) acrylate group-containing functional group, an oxetane group or oxetane group-
R ⁷ and R ⁸ are each independently hydrogen, a crosslinkable functional group, an unsubstituted or substituted C 1 to C 20 alkyl group, or an unsubstituted or substituted C 5 to C 20 cycloalkyl group,
R ⁹ , R ¹⁰ and R ¹¹ are each independently selected from the group consisting of hydrogen, a crosslinkable functional group, an unsubstituted or substituted C 1 to C 20 alkyl group, an unsubstituted or substituted C 5 to C 20 cycloalkyl group, An aryl group of C30,
0 &lt; y &lt; 1, 0? Y <1, 0? Z <1, 0? W <1, x + y + z + w = 1).
The composition for a window film according to claim 4, wherein the second silicone resin is represented by the following general formulas (2-1-1) and (2-1-2)
&Lt; Formula (2-1-1)
(EcSiO3 / ₂ ) _x1 (GpSiO3 / ₂ ) _x2
(Wherein, in the formula 2-1-1, Ec represents a 2- (3,4-epoxycyclohexyl) ethyl group, Gp represents a 3-glycidoxypropyl group, 0? X1 <1, 0? X2 <1, x1 + x2 = 1, x1 + x2 <&gt; 0).
<Formula 2-1-2>
(EcSiO3 / ₂ ) _x1 (GpSiO3 / ₂ ) _x2 (SiO4 / ₂ ) _w
X is in the range of 0 < x < 1, 0 < w (1) <1, x1 + x2 + w = 1).
The composition for a window film according to claim 5, wherein in the formula (2-1-1), 0.85? X1? 0.99 and 0.01? X2? 0.15.
The composition for a window film according to claim 4, wherein the first silicone resin and the second silicone resin in the curable resin are contained in an amount of 5 to 80 wt% and 20 to 95 wt%, respectively.
The composition for a window film according to claim 1, wherein the crosslinking agent comprises at least one of a chain aliphatic epoxy monomer, a cyclic aliphatic epoxy monomer, a hydrogenated aromatic hydrocarbon epoxy monomer, an oxetane monomer, and a (meth) acrylic monomer .
A flexible window film comprising a substrate layer and a coating layer formed on the substrate layer, wherein the coating layer is formed from the composition for a window film of any one of claims 1 to 8.
The flexible window film according to claim 9, wherein the flexible window film has a pencil hardness of 4H or more and a radius of curvature of 2.0 mm or less.
10. The method of claim 9, wherein the substrate layer comprises a film laminate,
Wherein the film laminate is a laminate of two or more films laminated by an adhesive layer.
The flexible window film of claim 11, wherein the film laminate is a laminate of a first film, a second film, and the first film and the second film by the adhesive layer.
13. The method according to claim 12, wherein the first film and the second film are films formed of at least one of a polyester resin, a polycarbonate resin, a polyimide resin, a poly (meth) acrylate resin and a cyclic olefin polymer resin Flexible window film.
12. The pressure-sensitive adhesive composition of claim 11, wherein the pressure-sensitive adhesive layer comprises a monomer mixture for a (meth) acrylic copolymer having a hydroxyl group; Initiator; And a composition for a pressure-sensitive adhesive layer comprising at least one of a macromonomer and an organic nanoparticle.
15. The flexible window film of claim 14, wherein the monomer mixture comprises a hydroxyl group-containing (meth) acrylate and an alkyl group-containing (meth) acrylate.
16. The flexible window film of claim 15, wherein the monomer mixture further comprises a comonomer.
15. The flexible window film according to claim 14, wherein the organic nanoparticles comprise core-shell particles satisfying the following formula 1:
<Formula 1>
Tg (c) < Tg (s)
(Unit: 占 폚), and Tg (s) is the glass transition temperature (unit: 占 폚) of the shell.
The flexible window film according to claim 14, wherein the organic nanoparticles have an average particle diameter of 10 nm to 400 nm.
The flexible window film according to claim 12, wherein the first film and the second film each have a thickness of 10 탆 to 100 탆, and the adhesive layer has a thickness of 10 탆 to 75 탆.

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