KR102106167B1 - Composition for window film and flexible window film prepared using the same - Google Patents

Abstract

Provided is a composition for a window film comprising a first silicone resin of Formula 1, a second silicone resin of Formula 2, inorganic hollow particles, a crosslinking agent, an initiator, and a fluorine-based leveling agent, and a flexible window film formed therefrom.

Description

Composition for window film and flexible window film formed therefrom {COMPOSITION FOR WINDOW FILM AND FLEXIBLE WINDOW FILM PREPARED USING THE SAME}

The present invention relates to a composition for a window film and a flexible window film formed therefrom. More specifically, the present invention relates to a composition for a window film and a flexible window film formed therefrom to provide a window coating layer that can increase the total light transmittance, increase the anti-glare effect, have excellent appearance, and have excellent flexibility and pencil hardness. .

In the display device, a flexible display device having flexibility to fold and expand while replacing a glass substrate or a high-hardness substrate with a film has been developed. The flexible display device is thin, lightweight, and shock-resistant, and can be folded and unfolded. Window films should also have good flexibility and hardness.

Since the window film is located at the outermost part of the display device, the total light transmittance should be good. The existing window film has a total light transmittance of less than 90%, and thus the transmittance to internal light or external light is low, thereby deteriorating the display screen quality. Meanwhile, the window film may further include a functional layer having an anti-glare effect. The anti-glare film is formed on the top layer of the window film so that there is no glare even in sunlight or indoor lighting. However, it may be difficult to implement an anti-glare effect when laminating an anti-glare film on a window film. Therefore, there is a need for a window film that has a high total light transmittance and can simultaneously obtain an anti-glare effect.

Background art of the present invention is disclosed in Japanese Patent Publication No. 2007-176542.

The problem to be solved by the present invention is to provide a composition for a window coating layer having a high total light transmittance and providing an anti-glare effect and having a good appearance.

Another problem to be solved by the present invention is to provide a composition for a window coating layer capable of providing a window coating layer having excellent flexibility and folding property and a high pencil hardness.

Another problem to be solved by the present invention is to provide a window film having high total light transmittance, anti-glare effect, excellent flexibility and folding property, and high pencil hardness.

The composition for a window film of the present invention may include a first silicone resin of Formula 1, a second silicone resin of Formula 2, inorganic hollow particles, a crosslinking agent, an initiator, and a fluorine leveling agent:

<Formula 1>

(R ¹ SiO _3/2 ) _x (R ² R ³ SiO _2/2 ) _y (R ⁴ R ⁵ R ⁶ SiO _1/2 ) _z (SiO _4/2 ) _w

(In Formula 1, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , x, y, z and w are as defined in the detailed description of the invention below)

<Formula 2>

(R _a SiO _{(4-a) / 2} ) _x (X _b SiO _{(4-b) / 2} ) _y

(In the formula 2, R, X, a, b, x and y are as defined in the detailed description of the invention below).

The flexible window film of the present invention includes a base layer and a coating layer formed on the base layer, wherein the flexible window film has a total light transmittance of 90% or more, a haze of 50% to 80%, a radius of curvature of 5.0 mm or less, RIQ can be 10 or higher.

The present invention provides a composition for a window coating layer having a high total light transmittance and providing an anti-glare effect and having a good appearance.

The present invention provides a composition for a window coating layer that can provide a window coating layer having excellent flexibility and folding property and high pencil hardness.

The present invention provides a window film having high total light transmittance, anti-glare effect, excellent flexibility and folding property, and high pencil hardness.

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

Embodiments will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains can easily practice. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. In the drawings, parts not related to the description are omitted in order to clearly describe the present invention, and the same reference numerals are used for the same or similar elements throughout the specification.

In this specification, "upper" and "lower" are defined based on the drawings, and "upper" may be changed to "lower" and "lower" may be changed to "upper" according to the viewpoint of the city, or "on" or What is referred to as "on" may include not only directly above, but also through other structures in the middle. On the other hand, what is referred to as "directly on (directly on)" or "directly above" means that there is no intervening structure.

In the present specification, "epoxy group" is a glycidyl group, a glycidoxy group or an epoxidized C4 to C20 cycloalkyl group, and "epoxy group-containing functional group" is a C1 to C20 alkyl group having an epoxy group or a C5 to C20 cycloalkyl group having an epoxy group. to be.

“Halogen” as used herein refers to fluorine, chlorine, bromine or iodine, “(meth) acrylic” refers to acrylic and / or methacryl, and “substituted” unless at least one of the functional groups is specifically mentioned. Hydrogen atom is a hydroxyl group, unsubstituted C1 to C10 alkyl group, C1 to C10 alkoxy group, C3 to C10 cycloalkyl group, unsubstituted C6 to C20 aryl group, C7 to C20 arylalkyl group, C1 to C10 alkyl group Means substituted with a substituted C6 to C20 aryl group or a C1 to C10 alkyl group substituted with a C1 to C10 alkoxy group.

In the present specification, “Ec” is a 2- (3,4-epoxycyclohexyl) ethyl group, “Gp” is a 3-glycidoxypropyl group, “Me” is a methyl group, and “Fd” is 1H, 1H, 2H, 2H- The perfluorodecyl group, "Fo" is a 1H, 1H, 2H, 2H-perfluorooctyl group.

In this specification, "RIQ (Reflected Image Quality)" is to measure the sharpness of the reflected image on the surface of the window coating layer. RIQ is measured by Rhopoint IQ of Rhopoint, and can be a value from 0 to 100. The larger the RIQ value, that is, closer to 100, means that the surface of the window coating layer is smooth and the appearance is excellent.

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 the present embodiment may include an epoxy group or a first silicone resin having an epoxy group-containing functional group, a fluorine-containing second silicone resin, inorganic hollow particles, a crosslinking agent, an initiator, and a fluorine-based leveling agent.

The composition for a window film includes a first silicone resin, a second silicone resin, inorganic hollow particles, a crosslinking agent, an initiator, and a fluorine-based leveling agent, so that the total light transmittance of the window film can be increased. In addition, the composition for a window film can also have an anti-glare effect when forming a window coating layer on a base layer, so there is no need to form a separate anti-glare layer on the window coating layer, so that the window film can be thinned. As described below, the anti-glare effect can be confirmed by the haze of the window film. In addition, the composition for the window film may be made to be usable in a flexible display device because it has good flexibility when folding in the direction of the substrate layer or the direction of the window coating layer in the direction of the window film, even though it contains solid particles such as inorganic hollow particles. In addition, the composition for the window film may implement a window film that has good appearance while having a specific range of haze.

Specifically, the composition for a window film of this embodiment may include a first silicone resin of Formula 1, a second silicone resin of Formula 2, inorganic hollow particles, a crosslinking agent, an initiator, and a fluorine-based leveling agent. This will be described in detail below.

1st silicone  Suzy

The first silicone resin is a non-fluorine-based silicone resin that does not contain fluorine, and may be represented by Formula 1 below, and these may be included alone or in combination of two or more. The first silicone resin may be a binder forming a window coating layer:

<Formula 1>

(R ¹ SiO _3/2 ) _x (R ² R ³ SiO _2/2 ) _y (R ⁴ R ⁵ R ⁶ SiO _1/2 ) _z (SiO _4/2 ) _w

(In the above, R ¹ is an epoxy group or an epoxy group-containing functional group,

R ² and R ³ are each independently hydrogen, a crosslinkable functional group, an unsubstituted or substituted C1 to C20 alkyl group, or an unsubstituted or substituted C5 to C20 cycloalkyl group,

R ⁴ , R ⁵ and R ⁶ are each independently hydrogen, a crosslinkable functional group, an unsubstituted or substituted C1 to C20 alkyl group, an unsubstituted or substituted C5 to C20 cycloalkyl group, or an unsubstituted or substituted C6 to C30 aryl group,

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

Specifically, R ¹ may be 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 . Specifically, R ² and R ³ may each independently be a C1 to C20 alkyl group having an epoxidized C4 to C20 cycloalkyl group, a C1 to C10 alkyl group, more specifically an epoxycyclohexylethyl group or a methyl group. In Formula 1, the crosslinkable functional group means an epoxy group, an epoxy group-containing functional group, an oxetanyl group or an oxetanyl group-containing functional group (C1 to C20 alkyl group having an oxetanyl group or a C5 to C20 cycloalkyl group having an oxetanyl group). . Among them, the first silicone resins of the following Chemical Formulas 1-1 and 1-2 are more preferable to secure the appearance, hardness, or flexibility of the window film.

In one embodiment, the first silicone resin may be represented by Formula 1-1 or 1-2 below:

<Formula 1-1>

(R ^1a SiO _3/2 ) _x1 (R ^1b SiO _3/2 ) _x2

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

<Formula 1-2>

(R ^1a SiO _3/2 ) _x1 (R ^1b SiO _3/2 ) _x2 (SiO _4/2 ) _w

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

In Formula 1-1, 0.70≤x1 <1, 0 <x2≤0.30, specifically 0.80≤x1 <1, 0 <x2≤0.20, and more specifically 0.85≤x1≤0.99, 0.01≤x2≤0.15. . Alternatively, in Formula 1-1, x1 may be 1 and x2 may be 0. In the above range, the flexibility and hardness of the window film may be improved.

In Formula 1-2, 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≤0.30, and more specifically 0.40≤ It may be x1≤0.95, 0.01≤x2≤0.40, 0.01≤w≤0.20. In the above range, the flexibility and hardness of the window film may be improved.

For example, in Formulas 1-1 and 1-2, R ^1a may be a C1 to C20 alkyl group having an epoxidized C4 to C20 cycloalkyl group, and R ^1b may have a glycidyl group or a glycidoxy group. , C1 to C20 may be an alkyl group.

More specifically, the first silicone resin may be represented by the following Chemical Formulas 1-1-1 or 1-1-2:

<Formula 1-1-1>

(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2

(In the above, 0≤x1≤1, 0≤x2≤1, x1 + x2 = 1, x1 + x2 ≠ 0).

<Formula 1-1-2>

(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2 (SiO _4/2 ) _w

(In the above, 0 <x1 <1, 0 <x2 <1, 0 <w <1, x1 + x2 + w = 1).

The first silicone resin may have a weight average molecular weight of 2,000 g / mol to 20,000 g / mol, specifically 4,000 g / mol to 10,000 g / mol, and more specifically 4,500 g / mol to 7,000 g / mol. In the above range, the window coating layer may be supported, and hardness and flexibility may be improved simultaneously. The first silicone resin may have a polydispersity (PDI) of 1.0 to 3.0, specifically 1.5 to 2.5, and an epoxy equivalent of 0.1 mol / 100 g to 1.0 mol / 100 g, specifically 0.3 mol / 100 g to 0.8 mol / 100 g. . In the above range, the coating property of the composition may be good, and the coating properties may have a stable effect.

The first silicone resin is 30% by weight to 80% by weight, specifically 40% by weight to 65% by weight of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent, more specifically It may be included as 50% to 65% by weight. In the above range, it may be effective to increase the hardness of the window film.

Silicon 2  Suzy

The second silicone resin is a silicone resin containing fluorine, and may be represented by the following Chemical Formula 2, and these may be included alone or in combination of two or more. The second silicone resin may increase the total light transmittance of the window coating layer together with the inorganic hollow particles and enhance the anti-glare effect. When the second silicone resin is not used, the flatness of the window film surface may be lowered and the appearance may be poor:

<Formula 2>

(R _a SiO _{(4-a) / 2} ) _x (X _b SiO _{(4-b) / 2} ) _y

(In the above, R is an epoxy group, an epoxy group-containing functional group, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C5 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group,

X is a substituted or unsubstituted C1 to C30 alkyl group containing one or more fluorine, a substituted or unsubstituted C5 to C20 cycloalkyl group containing one or more fluorine, or a substituted or unsubstituted one or more fluorine containing fluorine A substituted C6 to C20 aryl group,

a is an integer from 0 to 3, b is an integer from 1 to 3, 0≤x <1, 0 <y≤1, x + y = 1).

Specifically, R is an epoxy group or an epoxy group-containing functional group, a C1 to C20 alkyl group having an epoxidized C4 to C20 cycloalkyl group, a C1 to C20 alkyl group having a glycidoxy group, or a C1 to C10 alkyl group, more specifically It may be an epoxycyclohexylethyl group, glycidoxypropyl group, methyl group or ethyl group. Specifically, X is C1 to C10 fluoroalkyl group, C1 to C10 perfluoroalkyl group, C1 to C10 fluoroalkyl group C1 to C10 alkyl group, or C1 to C10 perfluoroalkyl group C1 to It may be an alkyl group of C10. More specifically, X is a 1H, 1H, 2H, 2H-perfluorodecyl group, 1H, 1H, 2H, 2H-perfluorooctyl group, or 1H, 1H, 2H, 2H-perfluorohexyl group, etc. Can be.

Specifically, in Formula 2, 0.0001≤x≤0.9999, 0.0001≤y≤0.9999, more specifically 0.8000≤x≤0.9999, 0.0001≤y≤0.2000; It may be 0.900≤x≤0.995, 0.005≤y≤0.100. In the above range, the total light transmittance of the window film is improved and an anti-glare effect may be produced.

In one embodiment, the second silicone resin may be represented by the following Chemical Formula 2-1, Chemical Formula 2-2 or Chemical Formula 2-3:

<Formula 2-1>

(RSiO _3/2 ) _x (XSiO _3/2 ) _y

(In the above, R and X are as defined in Formula 2 above,

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

<Formula 2-2>

(RSiO _3/2 ) _x1 (RR'SiO _2/2 ) _x2 (XSiO _3/2 ) _y

<Formula 2-3>

(RSiO _3/2 ) _x1 (R'SiO _3/2 ) _x2 (XSiO _3/2 ) _y

(In the above, R and X are as defined in Formula 2 above,

R 'is an epoxy group, an epoxy group-containing functional group, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C5 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group, R and R' is Different from each other,

0 <x1 <1, 0 <x2 <1, 0 <y <1, x1 + x2 + y = 1).

Specifically, in Formulas 2-1 to 2-3, 0.0001≤x or x1 + x2≤0.9999, 0.0001≤y≤0.9999, 0.8000≤x or x1 + x2≤0.9999, 0.0001≤y≤0.2000, and more specifically 0.9000 ≤x or x1 + x2≤0.995, and 0.005≤y≤0.1000. In the above range, there may be a surface leveling effect.

More specifically, the second silicone resin may be represented by the following formulas 2-1-1 to 2-1-10:

<Formula 2-1-1>

(EcSiO _3/2 ) _x (FdSiO _3/2 ) _y

<Formula 2-1-2>

(EcSiO _3/2 ) _x (FoSiO _3/2 ) _y

<Formula 2-1-3>

(GpSiO _3/2 ) _x (FdSiO _3/2 ) _y

<Formula 2-1-4>

(GpSiO _3/2 ) _x (FoSiO _3/2 ) _y

<Formula 2-1-5>

(EcSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FdSiO _3/2 ) _y

<Formula 2-1-6>

(EcSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FoSiO _3/2 ) _y

<Formula 2-1-7>

(GpSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FdSiO _3/2 ) _y

<Formula 2-1-8>

(GpSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FoSiO _3/2 ) _y

<Formula 2-1-9>

(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2 (FdSiO _3/2 ) _y

<Formula 2-1-10>

(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2 (FoSiO _3/2 ) _y

(In the above, 0 <x <1, 0 <y <1, x + y = 1, 0 <x1 <1, 0 <x2 <1, 0 <y <1, x1 + x2 + y = 1).

The second silicone resin may have a fluorine content of 0.1% to 50% by weight, specifically 0.2% to 30% by weight, more specifically 0.5% to 20% by weight, and more specifically 1% to 10% by weight. You can. In the above range, the appearance of the window film may be improved and transparency may be good. The second silicone resin may have a weight average molecular weight of 2,000 g / mol to 20,000 g / mol, specifically 4,000 g / mol to 10,000 g / mol, and more specifically 4,500 g / mol to 6,000 g / mol. In the above range, it is possible to improve the total light transmittance of the window film and increase the anti-glare effect. The second silicone resin may have a polydispersity (PDI) of 1.0 to 3.0, specifically 1.5 to 2.5, and an epoxy equivalent of 0.1 mol / 100 g to 1.0 mol / 100 g, specifically 0.3 mol / 100 g to 0.8 mol / 100 g. . In the above range, the coating property of the composition may be good, and the coating properties may have a stable effect.

The second silicone resin is the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, the fluorine-based leveling agent 0.4% to 1.0% by weight, specifically 0.6% to 0.9% by weight, more specifically 0.7 It may be included by weight to 0.9% by weight. In the above range, it is possible to increase the surface leveling effect of the window film and to make the appearance good while providing an anti-glare effect.

Crosslinker

The crosslinking agent can be cured with the first silicone resin and the second silicone resin by containing a crosslinkable functional group, thereby increasing the hardness of the window film and improving flexibility. The crosslinking agent may further increase the flexibility of the coating layer by further including at least one of a chained aliphatic hydrocarbon group, a cyclic aliphatic hydrocarbon group, and a hydrogenated aromatic hydrocarbon group. The crosslinking agent may include one or more of a chain aliphatic epoxy monomer, a cyclic aliphatic epoxy monomer, a hydrogenated aromatic hydrocarbon epoxy monomer, and an oxetane monomer, which may be included alone or in combination.

Chain aliphatic epoxy monomers are 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycol Cydyl 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 epoxy stearate; Octyl stearate; Epoxidized linseed oil; And epoxidized polybutadiene.

The cyclic aliphatic epoxy monomer is a compound having one or more epoxy groups in an 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-epoxy-6-methyl 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-3', 4'- Epoxycyclohexanecarboxylate, 1,4-cyclohexanedimethanol bis (3,4-epoxycyclohexanecarboxylate), di (3,4-epoxycyclohexylmethyl) ether of ethylene glycol, ethylenebis (3, 4-epoxycyclohex Acid carboxylate)), 3,4-epoxycyclohexylmethyl (meth) acrylate, bis (3,4-epoxycyclohexylmethyl) adipate, 4-vinylcyclohexenedioxide, vinylcyclohexene monooxide And the like.

The hydrogenated aromatic hydrocarbon epoxy monomer refers to a compound obtained by selectively hydrogenating an aromatic epoxy monomer under 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; Novolac-type epoxy resins such as phenol novolac epoxy resins, cresol novolac epoxy resins, and hydroxybenzaldehyde phenol novolac epoxy resins; And glycidyl ethers of tetrahydroxyphenylmethane, glycidyl ethers of tetrahydroxybenzophenone, and polyfunctional epoxy resins such as epoxidized polyvinyl phenol.

The oxetane monomers are 3-methyloxetane, 2-methyloxetane, 2-ethylhexyloxetane, 3-oxetanol, 2-methyleneoxetane, 3,3-oxetane methanethiol, 4- (3-methyl Oxetan-3-yl) benzonitrile, N- (2,2-dimethylpropyl) -3-methyl-3-oxetanmethaneamine, N- (1,2-dimethylbutyl) -3-methyl-3- Oxetanmethaneamine, (3-ethyloxetan-3-yl) methyl (meth) acrylate, 4-[(3-ethyloxetan-3-yl) methoxy] butan-1-ol, 3-ethyl- 3-hydroxymethyloxetane, xylenebisoxetane, 3- [ethyl-3 [[(3-ethyloxetane-3-yl)] methoxy] methyl] oxetane, or more, It is not limited to this.

The crosslinking agent is 5% by weight to 20% by weight, specifically 8% by weight to 15% by weight, more specifically 9% by weight of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. To 15% by weight. In the above range may increase the pencil hardness and flexibility of the window film.

Initiator

The initiator is to cure the first silicone resin and the second silicone resin, and may use one or more of a photocationic initiator and a photoradical initiator, and may be used alone or in combination of two or more. As the photocationic initiator, those commonly known to those skilled in the art can be used, and onium salts containing cations and anions can be used. Specifically, cations include diphenyl iodonium, 4-methoxydiphenyl iodonium, bis (4-methylphenyl) iodonium, bis (4-tert-butylphenyl) iodonium, bis (dodecylphenyl) iodonium, (4 -Marylphenyl) [4- (2-methylpropyl) phenyl] diaryl iodonium such as iodonium, triarylsulfonium such as triphenylsulfonium, diphenyl-4-thiophenoxyphenylsulfonium, bis [4 -(Diphenylsulfonio) phenyl] sulfide, and the like, and anions include hexafluorophosphate, tetrafluoroborate, hexafluoroantimonate, hexafluoroarsenate, and hexachloroantimonate. Can be mentioned.

The initiator is 1.0% by weight to 3.0% by weight, specifically 1.5% by weight to 2.5% by weight, more specifically 1.8% by weight of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. To 2.5% by weight. In the above range, the silicone resin can be sufficiently cured and a residual amount of the initiator remains to prevent the window film from deteriorating in optical properties (transmittance, color, light resistance, etc.).

Inorganic hollow particles

The inorganic hollow particles can increase the total light transmittance of the window coating layer together with the second silicone resin and enhance the anti-glare effect. If the inorganic hollow particles are not used, there may be a problem in that the total light transmittance decreases.

The inorganic hollow particles may have a refractive index of 1.4 or less, specifically 1.33 to 1.38. The average particle diameter (D50) of the inorganic hollow particles may be 30 nm to 100 nm, specifically 40 nm to 70 nm. It can be included in the window coating layer in the above range, it can increase the total light transmittance and increase the hardness of the window film. Inorganic hollow particles include silica, mullite, alumina, silicon carbide (SiC), MgO-Al ₂ O ₃ -SiO ₂ , Al ₂ O ₃ -SiO ₂ , MgO-Al ₂ O ₃ -SiO ₂ -LiO ₂ , Or a mixture of these, which may be surface-treated.

The inorganic hollow particles may be included as the particles themselves, but may be included as a solution containing inorganic hollow particles. The solution containing the inorganic hollow particles may contain other components in addition to the inorganic hollow particles. The other component is included in the composition for the window coating layer, but may be a component that does not affect the physical properties of the window film.

The inorganic hollow particles may be included in a total amount of 10% to 40% by weight, specifically 10% to 38% by weight, of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. In the above range, the total light transmittance of the window film may be increased, and the haze may have an appropriate range to increase the anti-glare effect.

Fluorine Leveling agent

The fluorine-based leveling agent may suppress the generation of bubbles when using the inorganic hollow particles and provide a leveling effect to the window coating layer. Inorganic hollow particles are agglomerated between particles, and the dispersibility of the inorganic hollow particles is increased by a fluorine-based leveling agent to facilitate coating of the composition. If a fluorine-based leveling agent is not used, there may be a problem of surface flatness and bubble generation.

The fluorine-based leveling agent may be a commercially available product such as Megaface F-553 (DIC), but is not limited thereto.

The fluorine-based leveling agent is 3% by weight to 8% by weight, specifically 4% by weight to 7% by weight, more specifically 5 of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. It may be included by weight to 7% by weight. In the above range, it is possible to suppress the generation of bubbles in the window coating layer and improve the surface quality of the window coating layer.

additive

The composition for the window film may further include an additive. Additives can provide additional functionality to the window film. Additives may include additives that are commonly added to window films. Specifically, the additive may include, but is not limited to, one or more of UV absorbers, reaction inhibitors, adhesion improvers, thixotropic agents, conductivity imparting agents, dye modifiers, stabilizers, antistatic agents, antioxidants. The adhesion promoter may include a silane compound having an epoxy or alkoxysilyl group. The thixotropic agent may include fumed silica and the like. The conductivity imparting agent may include metal powders such as silver and copper aluminum. Pigment modifiers may include pigments, dyes, and the like. The UV absorber can enhance the light resistance of the window film. UV absorbers can be used conventional absorbers known to those skilled in the art. Specifically, the UV absorber may include, but is not limited to, one or more UV absorbers of triazine-based, benzimidazole-based, benzophenone-based, and benzotriazole-based.

The additive may be included in an amount of 0.01 to 20 parts by weight based on 100 parts by weight of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent based on solid content. In the above range, it is possible to exert the effect of the additive while improving the hardness, flexibility, and transmittance of the window film.

The composition for window films may further include a solvent to facilitate coating properties, coating properties, or processability. The solvent may include, but is not limited to, one or more of methyl ethyl ketone, methyl isobutyl ketone, and propylene glycol monomethyl ether acetate.

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

1, the flexible window film 100 according to an embodiment of the present invention includes a base layer 110 and a coating layer 120, the coating layer 120 is a window film according to embodiments of the present invention It may be formed of a composition.

The base layer 110 may support 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 attached to a display unit, a touch screen panel, or a polarizing plate by an adhesive layer or the like. The base layer 110 may be formed of an optically transparent and flexible resin. For example, resins include polyester resins including polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, etc., polycarbonate resins, polyimide resins, polystyrene resins, polymethyl methacrylate, and the like. It may include one or more of the poly (meth) acrylate resin. The resin may be included alone or in mixture in the base layer 110. The base layer 110 may have a thickness of 10 μm to 200 μm, specifically 20 μm to 150 μm, and more specifically 50 μm to 100 μm. It can be used in the flexible window film in the above range.

1 shows a case where the base layer is a single layer. However, the base layer may be included in the scope of the present invention even when a plurality of base layers are stacked. For example, the base layer may be a laminate of the first base layer and the second base layer, and the first base layer and the second base layer may be laminated by a transparent adhesive, for example, optical clear adhesive (OCA). The OCA type is not particularly limited. The first base layer and the second base layer may be selected from the base layer described above. The thickness and material of the first base layer and the second base layer may be the same or different. OCA may have a total light transmittance of 90% or more. Within the above range, the first base layer and the second base layer can be adhered to each other without affecting the physical properties of the window film.

The coating layer 120 is formed on the base layer 110 to protect the base layer 110 and the display unit, the touch screen panel or the polarizing plate, improves appearance, and has high flexibility and high hardness, so that it can be used for flexible display devices can do. The coating layer 120 may have a thickness of 5 μm to 100 μm, specifically 10 μm to 80 μm. It can be used in the flexible window film in the above range. Although not illustrated in FIG. 1, functional surface layers such as an anti-reflection layer, an anti-glare layer, and a hard coating layer are further formed on the other surface of the coating layer 120 to provide additional functions to the flexible window film. In addition, although not shown in FIG. 1, the coating layer 120 may be further formed on the other surface of the base layer 110.

The flexible window film 100 has a total light transmittance of 90% or more, specifically 90% to 100%, haze of 50% to 80%, specifically 55% to 75%, and RIQ of 10 or more in the visible light region, specifically, at a wavelength of 400 nm to 800 nm. It can be 10 to 50. In the above range, the total light transmittance is high, the anti-glare effect, and the appearance is good, so it can be used as the outermost window film of the optical display device, and the image quality can be improved.

The flexible window film 100 may have a reflectance of 10.0% or less, for example, 0 to 9.55%. In the above range, the anti-glare effect may be good.

The flexible window film 100 may have a pencil hardness of 4H or more and a radius of curvature of 5.0mm or less. In the above range, it is good in hardness and flexibility and can be used as a flexible window film. Specifically, the flexible window film 100 may have a pencil hardness of 4H to 9H and a radius of curvature of 0.1 mm to 5.0 mm. The flexible window film 100 may have a thickness of 5 μm to 300 μm. It can be used as a flexible window film in the above range.

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

Referring to Figure 2, the flexible window film 200 according to another embodiment of the present invention, except that the adhesive layer 130 is further formed on the other surface of the base layer 110 according to an embodiment of the present invention It 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 to facilitate adhesion between the flexible window film and the touch screen panel, polarizing plate, or display unit. It is substantially the same as the flexible window film according to an embodiment of the present invention, except that the adhesive layer is further formed. Therefore, 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 may be disposed under the flexible window film 200, and may be formed of a composition for an adhesive layer. Specifically, the adhesive layer 130 may be formed of a composition for an adhesive layer including an adhesive resin such as (meth) acrylic resin, urethane resin, silicone resin, epoxy resin, curing agent, photoinitiator, and 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, or a heteroalicyclic group, and may include a common (meth) acrylic copolymer. Specifically, a (meth) acrylic monomer having an unsubstituted alkyl group of C1 to C10, a (meth) acrylic monomer having an alkyl group of C1 to C10 having one or more hydroxyl groups, and a (meth) acrylic monomer having an aromatic group of C6 to C20 , (Meth) acrylic monomer having a carboxylic acid group, (meth) acrylic monomer having an alicyclic group of C3 to C20, C3 to C10 heteroalicyclic having one or more of nitrogen (N), oxygen (O), sulfur (S) It may be formed of a monomer mixture containing at least one of the (meth) acrylic monomer having a group.

The curing agent is a polyfunctional (meth) acrylate, and a bifunctional (meth) acrylate such as hexanediol diacrylate; Trifunctional (meth) acrylate of trimethylolpropane tri (meth) acrylate; Tetrafunctional (meth) acrylates such as pentaerythritol tetra (meth) acrylate; Pentafunctional (meth) acrylates such as dipentaerythritol penta (meth) acrylate; Dipentaerythritol hexa (meth) acrylate, and other functional (meth) acrylates.

The photoinitiator may include the photoradical initiator described above as a conventional photoinitiator.

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

The composition for the adhesive layer may include 100 parts by weight of a (meth) acrylic resin, 0.1 parts by weight to 30 parts by weight of a curing agent, 0.1 parts by weight to 10 parts by weight of a photoinitiator, and 0.1 parts by weight to 20 parts by weight of a silane coupling agent. In the above range, the flexible window film can be well attached on the display unit, the touch screen panel or the polarizing plate.

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

Hereinafter, a flexible display device according to an exemplary embodiment of the present invention will be described with reference to FIGS. 3 and 4. 3 is a cross-sectional view of a flexible display device according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view according to an embodiment of the display unit of FIG. 3.

     Referring to FIG. 3, the flexible display device 300 according to an embodiment of the present invention includes a display unit 350a, an adhesive layer 360, a polarizing plate 370, a touch screen panel 380, and a flexible window film 390 ), And the flexible window film 390 may include 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 a substrate and an OLED, LED, or LCD element formed on the substrate. 4 is a cross-sectional view according to an embodiment of the display unit of FIG. 3. Referring to FIG. 4, the display 350a may include a lower substrate 310, a thin film transistor 316, an organic light emitting diode 315, a planarization layer 314, a protective film 318, and an insulating film 317. have.

The lower substrate 310 supports the display unit 350a, and a thin film transistor 316 and an organic light emitting diode 315 may be formed on the lower substrate 310. 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 and a power supply for driving the organic light emitting diode array.

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

A plurality of pixel regions are defined in the display area of the lower substrate 310 by crossing a plurality of driving wires (not shown) and sensor wires (not shown), and the thin film transistors 316 and the thin film transistors 316 for each pixel region ) And an organic light-emitting diode array including an organic light-emitting diode 315 connected thereto. In the 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 unit may be formed on one side or both sides of the display area.

The thin film transistor 316 is controlled by applying an electric field perpendicular to the current flowing through the semiconductor, and may be formed on the lower substrate 310. The thin film transistor 316 may include a gate electrode 310a, a gate insulating layer 311, a semiconductor layer 312, a source electrode 313a, and a drain electrode 313b. The thin film transistor 316 is an oxide thin film transistor using an oxide such as indium gallium zinc oxide (IGZO), ZnO, TiO as the semiconductor layer 312, an organic thin film transistor using an organic material as the semiconductor layer, and amorphous silicon as the semiconductor layer. It may be an amorphous silicon thin film transistor 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 to planarize the upper surfaces of the thin film transistor 316 and the circuit portion 310b so that the organic light emitting diode 315 is formed. The planarization layer 314 may be formed of a spin-on-glass (SOG) film, a polyimide-based polymer, or a polyacrylic polymer, but is not limited thereto.

The organic light emitting diode 315 implements a display by emitting light by itself, and may include a stacked first electrode 315a, an organic light emitting layer 315b, and a second electrode 315c. Adjacent organic light-emitting diodes may be separated through an insulating film 317. The organic light emitting diode 315 may include a back light emitting structure in which light generated in the organic light emitting layer 315b is emitted through the lower substrate or a front light emitting structure in which light generated in the organic light emitting layer 315b is emitted upward.

The protective layer 318 may cover the organic light emitting diode 315 to protect the organic light emitting diode 315. The protective layer 318 includes inorganic materials such as SiOx, SiNx, SiC, SiON, SiONC, and aC (amorphous carbon) ( It may be formed of an organic material such as meth) acrylate, epoxy-based polymer, imide-based polymer. 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 to FIG. 3 again, the adhesive layer 360 is to adhere the display unit 350a to the polarizing plate 370, and is formed of an adhesive composition comprising a (meth) acrylate-based resin, a curing agent, an initiator, and a silane coupling agent. Can be.

The polarizing plate 370 may implement polarization of internal light or prevent reflection of external light to implement a display or increase the contrast ratio of the display. The polarizing plate may be composed of a polarizer alone. Alternatively, the polarizing plate may include a polarizer and a protective film formed on one or both surfaces of the polarizer. Alternatively, the polarizing plate may include a polarizer and a protective coating layer formed on one or both surfaces of the polarizer. The polarizer, the protective film, and the protective coating layer can be used conventionally 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 may be driven by the signal. The touch screen panel 380 is formed by patterning a flexible and conductive conductor, and may include a second sensor electrode formed between the first sensor electrode and the first sensor electrode and crossing the first sensor electrode. have. Conductors for the touch screen panel 380 may include, but are not limited to, metal nanowires, conductive polymers, carbon nanotubes, and the like.

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

Although not illustrated in FIG. 3, an adhesive layer is further formed between the polarizing plate 370 and the touch screen panel 380 and / or between the touch screen panel 380 and the flexible window film 390, so that the polarizing plate, the touch screen panel, and the flexible The bonding between the window films can be strengthened. The adhesive layer may be formed of an adhesive composition comprising a (meth) acrylate-based resin, a curing agent, an initiator, and a silane coupling agent. In addition, although not shown in FIG. 3, since a polarizing plate is further formed under the display unit 350a, polarization of light can be realized.

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

5, the flexible display device 400 according to another embodiment of the present invention includes a display unit 350a, a touch screen panel 380, a polarizing plate 370, a flexible window film 390, and The window film 390 may include a flexible window film according to embodiments of the present invention. A flexible display according to an embodiment of the present 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 polarizing plate 370. It is substantially the same as the device. In addition, at this time, the touch screen panel 380 may be formed together with the display unit 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 may be thin and bright compared to the flexible display device according to an exemplary embodiment of the present invention. In addition, in this case, the touch screen panel 380 may be formed by vapor deposition or the like, but is not limited thereto. Although not shown in FIG. 5, between the display unit 350a and the touch screen panel 380 and / or between the touch screen panel 380 and the polarizing plate 370 and / or between the polarizing plate 370 and the flexible window film 390 The adhesive layer is further formed to increase the mechanical strength of the display device. The adhesive layer may be formed of an adhesive composition comprising a (meth) acrylate-based resin, a curing agent, an initiator, and a silane coupling agent. In addition, although not illustrated in FIG. 5, a polarizing plate is further formed under the display unit 350a to induce polarization of the inner light to improve the display image.

Hereinafter, a flexible display device according to another exemplary embodiment of the present invention will be described with reference to FIG. 6. 6 is a cross-sectional view of a flexible display device according to another embodiment of the present invention. Referring to FIG. 6, a flexible display device 500 according to another embodiment of the present invention includes a display unit 350b, an adhesive layer 360, and a flexible window film 390, and the flexible window film 390 May include a flexible window film according to embodiments of the present invention. It is substantially the same as the flexible display device according to an exemplary embodiment of the present invention, except that the display unit 350b can drive the device and the polarizing plate and the touch screen panel are excluded.

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

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

A first silicone resin is silicone monomer to provide a silicon monomer alone, or (R ¹ SiO _3/2) to provide (R ¹ SiO _3/2) of the formula (1); And _{^{(R 2 R 3 SiO 2/}} 2) a silicon monomer, to provide a ^{(R 4 R 5 R 6 SiO} 1/2) to provide the silicon monomer, (SiO _4/2) at least one mixture of the silicone monomers to provide for It can be prepared by hydrolysis and condensation reaction. (R ¹ SiO _3/2) to provide a silicone monomer is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl triethoxysilane, 3- doksi glycidyl trimethoxysilane, 3-glycidoxypropyltrimethoxysilane and the like can be the doksi propyl _{^{triethoxysilane, (R 2 R 3 SiO 2}} /2) to provide a silicon monomer include dimethyl dimethoxysilane, dimethyl diethoxysilane , Diethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyltriethoxysilane, and the like, (SiO _{4 / 2} ) to provide a silicone monomer may be tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and the like, but is not limited thereto. In one embodiment, the monomer mixture (R ¹ 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. Within this range, the hardness and flexibility of the window film can be improved.

The second silicone resin of the formula _{( 2} ) is a silicone mixture containing a silicone monomer providing (R _a SiO _{(4-a) / 2} ) and a silicone monomer providing (X _b SiO _{(4-b) / 2} ). It can be prepared by decomposition and condensation reactions. Specifically, the silicone monomer providing (R _a SiO _{(4-a) / 2} ) is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl Triethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyl Dimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyltriethoxysilane, and the like, but is not limited thereto. Specifically, the silicone monomer providing (X _b SiO _{(4-b) / 2} ) is 1H, 1H, 2H, 2H-perfluorodecyltrimethoxysilane, 1H, 1H, 2H, 2H-perfluoroox Tiltrimethoxysilane, 1H, 1H, 2H, 2H-perfluorohexyltrimethoxysilane, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, 1H, 1H, 2H, 2H-perfluoro Octyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorohexyltriethoxysilane, and the like, but is not limited thereto. In one embodiment, the monomer mixture is from 0.01 mol% to 99.99 mol%, specifically from 80 mol% to 99.99 mol%, more specifically from 90 mol% to 99.5 mol of a silicone monomer providing (R _a SiO _{(4-a) / 2} ) %, From 0.01 mol% to 99.99 mol% of a silicone monomer providing (X _b SiO _{(4-b) / 2} ), specifically from 0.01 mol% to 20 mol%, more specifically from 0.5 mol% to 10 mol%. In the above range, the appearance of the window film may be improved and glare may be less.

The hydrolysis and condensation reaction of the monomer mixture can be carried out according to a conventional method for preparing silicone resin. Hydrolysis may include reacting the monomer mixture in a mixture of water and one or more of a given acid, base. Specifically, HCl, HNO ₃ , acetic acid, and the like, and NaOH, KOH, and the like may be used as the base. The hydrolysis is performed at 20 ° C to 100 ° C for 10 minutes to 10 hours, and the condensation reaction can be performed 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 may be manufactured by a method of manufacturing a flexible window film including coating and curing the composition for a window film according to embodiments of the present invention on a base layer 110.

The method of coating the composition for the window film on the base layer 110 may be bar coating, spin coating, dip coating, roll coating, flow coating, die coating, etc., but is not limited. The composition for the window film may be coated on the substrate layer 110 to a thickness of 5 μm to 100 μm. In the above range, a desired coating layer may be secured, and hardness and flexibility may be excellent. Curing is to form a coating layer by curing the composition for a window film, and may include one or more of photocuring and thermosetting. Photocuring may involve irradiation with light amount of 10 mJ / cm ² to 1,000mJ / cm ² at a wavelength of 400nm or less. Heat curing may include treating at 40 ° C to 200 ° C for 1 hour to 30 hours. The composition for a window film in the above range can be sufficiently cured. For example, after photocuring, it may be thermally cured, and as a result, the hardness of the coating layer may be further increased. After coating the composition for the window film on the base layer 110 and then curing, it may further include drying the composition for the window film. After drying and curing, it is possible to prevent the surface roughness of the coating layer from being increased due to long-time photocuring or thermal curing. Drying may be performed at 40 ° C to 200 ° C for 1 minute to 30 hours, but is not limited thereto.

Hereinafter, the present invention will be described in more detail through examples, but these examples are for the purpose of description only and should not be construed as limiting the invention.

Production Example 1: First silicone resin

95 mol% of 2- (3,4-epoxycyclohexyl) ethyl trimethoxysilane (KBM-303, Shinyetsu) and 5 mol% of (3-glycidoxypropyl) trimethoxysilane (KBM-403, Shinyetsu) 400 g of the containing silicone monomer mixture was placed in a 1 L 3-neck flask. After adding 0.1 mol% of KOH to the silicone monomer mixture and 1 equivalent of water relative to the total silicone monomer, stirring at 65 ° C. for 8 hours, washing with toluene and concentrating, the first silicone resin (weight average by GPC) Molecular weight: 5,500 g / mol) (EcSiO _3/2 ) _0.95 (GpSiO _3/2 ) _0.05 was prepared.

Production Example 2: Second silicone resin

2- (3,4-epoxycyclohexyl) ethyl trimethoxysilane (KBM-303, Shin-Etsu Co.) 95 mol%, 1H, 1H, 2H, 2H-perfluorodecyl trimethoxysilane (Aldrich) 5 mol A total of 100 g of the% monomer mixture was placed in a 500 mL 3-neck flask. To the mixture, 0.5 mol% of KOH and 1.5 mol% of water were added to the mixture, and the mixture was stirred at 70 ° C. for 2 hours, and the solvent was removed with a vacuum distillation apparatus to remove the second silicone resin (gel permeation chromatography (GPC)). Weight average molecular weight by: 5,000g / mol) (EcSiO _3/2 ) _0.95 (FdSiO _3/2 ) _0.05 was prepared. Methyl ethyl ketone was added to set a solid content of 90% by weight.

Example 1

2.22 g of the first silicone resin of Preparation Example 1, 0.03 g of the second silicone resin of Preparation Example 2, crosslinking agent CY-179 (Ciba) 0.40 g, initiator diaryl iodonium salt IK-1 (YCAM) 0.06 g, inorganic hollow Silica-containing material XJA0256 (PELNOX, Hollow Silica Content: 5.5% by weight) 7.11g, Megaface F-553 (DIC) 0.18g mixed with a fluorine leveling agent and methylethylketone and 1-methoxypropan-2-ol as a solvent Was added and stirred for 30 minutes and air bubbles were removed for 30 minutes to prepare a composition for a window coating layer having a solid content concentration of 30% by weight.

The composition for the window coating layer is based on solid content, in the total of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow silica and the fluorine-based leveling agent, 62.74% by weight of the first silicone resin, 0.84% by weight of the second silicone resin, and the crosslinking agent 14.13% by weight, 2.11% by weight of the initiator, 13.82% by weight of the inorganic hollow silica, and 6.36% by weight of the fluorine-based leveling agent.

After coating the prepared window coating layer composition on a PI film (polyimide film, SDI, thickness: 80 μm), and drying at 80 ° C. for 2 minutes, exposure to 500 mJ / cm ² ultraviolet light to prepare a 10 μm thick coating film. After that, postcure was performed in an oven at 85 ° C. for 24 hr to prepare a window film.

Example 2

1.73 g of the first silicone resin of Preparation Example 1, 0.02 g of the second silicone resin of Preparation Example 2, 0.24 g of crosslinking agent CY-179 (Ciba), 0.05 g of initiator diaryl iodonium salt IK-1 (YCAM), inorganic hollow Silica-containing material XJA0256 (PELNOX, Hollow Silica Content: 5.5% by weight) 7.80 g, 0.15 g of Megaface F-553 (DIC) as a fluorine leveling agent, and methyl ethyl ketone and 1-methoxypropan-2-ol as a solvent Was added and stirred for 30 minutes and air bubbles were removed for 30 minutes to prepare a composition for a window coating layer having a solid content concentration of 25% by weight.

The composition for the window coating layer is based on solid content, in the total of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow silica and the fluorine-based leveling agent, 60.91% by weight of the first silicone resin, 0.84% by weight of the second silicone resin, and the crosslinking agent 10.63 wt%, initiator 2.20 wt%, inorganic hollow silica 18.83 wt% and fluorine-based leveling agent 6.59 wt%.

A window film was prepared in the same manner as in Example 1 using the prepared composition for a window coating layer.

Example 3

1.17 g of the first silicone resin of Production Example 1, 0.02 g of the second silicone resin of Production Example 2, 0.22 g of crosslinking agent CY-179 (Ciba), initiator diaryl iodonium salt IK-1 (YCAM) 0.04 g, inorganic hollow Silica-containing material XJA0256 (PELNOX, Hollow silica content: 5.5% by weight) 8.42 g, mixed with Megaface F-553 (DIC) 0.13 g with a fluorine leveling agent and methyl ethyl ketone and 1-methoxypropan-2-ol as a solvent Was added and stirred for 30 minutes and air bubbles were removed for 30 minutes to prepare a composition for a window coating layer having a solid content concentration of 20% by weight.

The composition for the window coating layer is based on solid content, in the total of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow silica and the fluorine-based leveling agent, 51.89% by weight of the first silicone resin, 0.88% by weight of the second silicone resin, and the crosslinking agent 12.36% by weight, 2.21% by weight of the initiator, 25.68% by weight of the inorganic hollow silica, and 6.98% by weight of the fluorine-based leveling agent.

A window film was prepared in the same manner as in Example 1 using the prepared composition for a window coating layer.

Comparative Example 1

4.098 g of the first silicone resin of Production Example 1, 0.0405 g of the second silicone resin of Production Example 2, 0.833 g of a crosslinking agent CY-179 (Ciba), an initiator diaryl iodonium salt IK-1 (YCAM) 0.085 g, MEK ( Methyl ethyl ketone) 2.07g, PGME (propylene glycol methyl ether) 2.88g was mixed and stirred for 30 minutes and air bubbles were removed for 30 minutes to prepare a composition for a window coating layer.

The composition for the window coating layer is 77.51% by weight of the first silicone resin, 0.76% by weight of the second silicone resin, 19.72% by weight of the crosslinking agent, and 2.01% by weight of the initiator, based on the solid content, the total of the first silicone resin, the second silicone resin, the crosslinking agent, and the initiator. Includes.

A window film was prepared in the same manner as in Example 1 using the prepared composition for a window coating layer.

Comparative Example 2

2.25 g of the first silicone resin of Preparation Example 1, crosslinking agent CY-179 (Ciba) 0.4 g, initiator diaryl iodonium salt IK-1 (YCAM) 0.06 g, inorganic hollow silica-containing material XJA0256 (PELNOX, hollow silica content : 5.5% by weight) 7.11g, fluorine-based leveling agent Megaface F-553 (DIC Co.) 0.18g was mixed and stirred for 30 minutes and air bubbles were removed for 30 minutes to prepare a composition for a window coating layer.

The composition for the window coating layer is based on solid content, 63.62% by weight of the first silicone resin, 14.07% by weight of the crosslinking agent, 14.13% by weight of the initiator, and 13.82% by weight of the inorganic hollow silica. % And 6.36% by weight of a fluorine-based leveling agent.

A window film was prepared in the same manner as in Example 1 using the prepared composition for a window coating layer.

Comparative Example 3

4.0g of the first silicone resin of Production Example 1, 0.04g of the second silicone resin of Production Example 2, 0.81g of crosslinking agent CY-179 (Ciba), initiator diaryl iodonium salt IK-1 (YCAM) 0.08g, fluorine leveling Zero Megaface F-553 (DIC Co.) 0.25g, MEK 2.02g, PGME 2.8g was mixed and stirred for 30 minutes and air bubbles were removed for 30 minutes to prepare a composition for a window coating layer.

The composition for the window coating layer is 73.14% by weight of the first silicone resin, 0.73% by weight of the second silicone resin, and 18.51% by weight of the crosslinking agent, based on the solid content, the total of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, and the fluorine-based leveling agent. 1.91% by weight of the initiator and 5.71% by weight of the fluorine-based leveling agent.

A window film was prepared in the same manner as in Example 1 using the prepared composition for a window coating layer.

Comparative Example 4

2.26 g of the first silicone resin of Preparation Example 1, 0.03 g of the second silicone resin of Preparation Example 2, crosslinking agent CY-179 (Ciba) 0.41 g, initiator diaryl iodonium salt IK-1 (YCAM) 0.06 g, inorganic hollow A composition for a window coating layer was prepared by mixing 7.24 g of silica-containing material XJA0256 (PELNOX, hollow silica content: 5.5 wt%), stirring for 30 minutes, and removing air bubbles for 30 minutes.

The composition for the window coating layer is 66.97% by weight of the first silicone resin, 0.96% by weight of the second silicone resin, and 15.19% by weight of the crosslinking agent, based on the solid content, the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, and the inorganic hollow silica. 2.13% by weight of initiator and 14.75% by weight of inorganic hollow silica.

A window film was prepared in the same manner as in Example 1 using the prepared composition for a window coating layer.

The physical properties of Table 1 below were evaluated for the window films produced in Examples and Comparative Examples, and the results are shown in Table 1 below.

(1) Pencil hardness: measured by JIS K5400 method using a pencil hardness tester (Heidon) for the coating layer of the window film. For pencil hardness measurement, pencils from 6B to 9H manufactured by Mitsubishi were used. The load of the pencil on the coating layer was 1 kg, the angle at which the pencil was drawn was 45 °, and the speed at which the pencil was drawn was 60 mm / min. If the scratch occurs more than once after 5 evaluations, the pencil hardness is measured using the pencil in the lower stage, and the maximum pencil hardness value when there are no scratches in all 5 times during the 5 evaluations.

(2) Total light transmittance: The window film was measured using a transmittance meter NDH2000 (NIPPON DENSHOKU). The standard is ASTM D 1003, and the wavelength of light is 550 nm. The light source is a halogen lamp 5V2A. The direction of light transmission was directed toward the window coating side of the film.

(3) Reflectance: The window film was measured using a reflectometer CM-3600A (KONICA MINOLTA). The wavelength range of 360 to 740 nm is measured at 10 nm intervals. The measurement diameter of the sample is φ8 mm. The direction of the light was directed to the window coating surface.

(4) Radius of curvature: The window film (width x length, 1 cm x 10 cm) was evaluated visually for crack occurrence with a vernier caliper for curvature testing. At this time, the compression direction was such that the coating layers contacted each other toward the bending direction, and the tensile direction was contacted with each other toward the bending direction of the base layer. The radius of curvature was measured by decreasing the radius from the larger value in the compression direction to the smaller direction, and the minimum radius of the JIG that does not crack was determined as the radius of curvature.

(5) Haze: The window film was measured in a visible light region at a wavelength of 400 nm at a wavelength of 400 nm with a haze meter of NDH 2000 (NIPPON DENSHOKU).

(6) RIQ: The window coating layer in the window film was measured by Rhopoint IQ of Rhopoint.

Example Comparative example One 2 3 One 2 3 4 1st silicone resin 62.74 60.91 51.89 77.51 63.62 73.14 66.97 Second silicone resin 0.84 0.84 0.88 0.76     0 0.73 0.96 Crosslinker 14.13 10.63 12.36 19.72 14.07 18.51 15.19 Initiator 2.11 2.20 2.21 2.01 2.13 1.91 2.13 Inorganic hollow particles 13.82 18.83 25.68 0 13.82    0 14.75 Fluorine leveling agent 6.36 6.59 6.98 0 6.36 5.71 0 Total ^* 100 100 100 100 100 100 100 Pencil hardness 4H 4H 4H 4H 4H 4H 4H Total light transmittance (%) 92.0 91.3 90.2 89.0 92.0 88.9 91.8 reflectivity(%) 8.70 9.16 9.52 9.82 8.82 9.85 8.80 Curvature radius (mm) 3 or less 3 or less 3 or less 3 or less 3 or less 3 or less 3 or less Haze
(%) 58.6 64.3 70.7 0.81 58.4 0.86 58.6 RIQ 15.2 12.8 10.7 60.4 8.0 87.6 2.3

Total *: The sum total of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine leveling agent.

As shown in Table 1, the composition for a window film of the present invention has a high total light transmittance and can provide an anti-glare effect, and has excellent appearance. The composition for a window film of the present invention can provide a window coating layer having excellent flexibility and folding property and high pencil hardness.

On the other hand, Comparative Examples 1 and 3, which do not contain inorganic hollow particles, have low haze and cannot provide an anti-glare effect. Comparative Example 2 and Comparative Example 4, which did not contain the second silicone resin or did not contain the fluorine-based leveling agent, had a low RIQ value and thus had poor appearance.

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

Claims (12)

A composition for a window coating layer comprising a first silicone resin of Formula 1, a second silicone resin of Formula 2, inorganic hollow particles, a crosslinking agent, an initiator, and a fluorine-based leveling agent,
<Formula 1>
(R ¹ SiO _3/2 ) _x (R ² R ³ SiO _2/2 ) _y (R ⁴ R ⁵ R ⁶ SiO _1/2 ) _z (SiO _4/2 ) _w
(In the formula 1, R ¹ is an epoxy group or an epoxy group-containing functional group,
R ² and R ³ are each independently hydrogen, a crosslinkable functional group, an unsubstituted or substituted C1 to C20 alkyl group, or an unsubstituted or substituted C5 to C20 cycloalkyl group,
R ⁴ , R ⁵ and R ⁶ are each independently hydrogen, a crosslinkable functional group, an unsubstituted or substituted C1 to C20 alkyl group, an unsubstituted or substituted C5 to C20 cycloalkyl group, or an unsubstituted or substituted C6 to C30 aryl group,
0 <x≤1, 0≤y <1, 0≤z <1, 0≤w <1, x + y + z + w = 1)
<Formula 2>
(R _a SiO _{(4-a) / 2} ) _x (X _b SiO _{(4-b) / 2} ) _y
(In the formula 2, R is an epoxy group, an epoxy group-containing functional group, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C5 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group,
X is a substituted or unsubstituted C1 to C30 alkyl group containing one or more fluorine, a substituted or unsubstituted C5 to C20 cycloalkyl group containing one or more fluorine, or a substituted or unsubstituted one or more fluorine containing fluorine A substituted C6 to C20 aryl group,
a is an integer from 0 to 3, b is an integer from 1 to 3, 0≤x <1, 0 <y≤1, x + y = 1),
The second silicone resin comprises at least one of the silicone resins represented by any one of the following formulas 2-1-1 to 2-1-10, a composition for a window coating layer:
<Formula 2-1-1>
(EcSiO _3/2 ) _x (FdSiO _3/2 ) _y
<Formula 2-1-2>
(EcSiO _3/2 ) _x (FoSiO _3/2 ) _y
<Formula 2-1-3>
(GpSiO _3/2 ) _x (FdSiO _3/2 ) _y
<Formula 2-1-4>
(GpSiO _3/2 ) _x (FoSiO _3/2 ) _y
(In the formulas 2-1-1 to 2-1-4, Ec is a 2- (3,4-epoxycyclohexyl) ethyl group, Gp is a 3-glycidoxypropyl group, Fd is 1H, 1H, 2H, 2H-perfluorodecyl group, Fo is 1H, 1H, 2H, 2H-perfluorooctyl group, 0 <x <1, 0 <y <1, x + y = 1),
<Formula 2-1-5>
(EcSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FdSiO _3/2 ) _y
<Formula 2-1-6>
(EcSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FoSiO _3/2 ) _y
<Formula 2-1-7>
(GpSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FdSiO _3/2 ) _y
<Formula 2-1-8>
(GpSiO _3/2 ) _x1 ((Me) ₂ SiO _2/2 ) _x2 (FoSiO _3/2 ) _y
<Formula 2-1-9>
(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2 (FdSiO _3/2 ) _y
<Formula 2-1-10>
(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2 (FoSiO _3/2 ) _y
(In the formulas 2-1-5 to 2-1-10, Ec is 2- (3,4-epoxycyclohexyl) ethyl group, Gp is 3-glycidoxypropyl group, Fd is 1H, 1H, 2H, 2H-perfluorodecyl group, Fo is 1H, 1H, 2H, 2H-perfluorooctyl group, Me is methyl group, 0 <x1 <1, 0 <x2 <1, 0 <y <1, x1 + x2 + y = 1).
The composition for a window coating layer of claim 1, wherein the inorganic hollow particles include hollow silica.
The window coating layer of claim 1, wherein the inorganic hollow particles are contained in an amount of 10 to 40% by weight of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. Composition.
The composition for a window coating layer of claim 1, wherein the inorganic hollow particles have an average particle diameter (D50) of 30 nm to 100 nm.
delete The window coating layer according to claim 1, wherein the second silicone resin is included in an amount of 0.4% to 1.0% by weight of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. Dragon composition.
According to claim 1, The first silicone resin is represented by the following formula 1-1-1 or 1-1-2, a composition for a window coating layer:
<Formula 1-1-1>
(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2
(In the formula 1-1-1, Ec is a 2- (3,4-epoxycyclohexyl) ethyl group, Gp is a 3-glycidoxypropyl group, 0≤x1≤1, 0≤x2≤1, x1 + x2 = 1, x1 + x2 ≠ 0).
<Formula 1-1-2>
(EcSiO _3/2 ) _x1 (GpSiO _3/2 ) _x2 (SiO _4/2 ) _w
(In the formula 1-1-2, Ec is a 2- (3,4-epoxycyclohexyl) ethyl group, Gp is a 3-glycidoxypropyl group, 0 <x1 <1, 0 <x2 <1, 0 <w <1, x1 + x2 + w = 1).
The window coating layer of claim 1, wherein the first silicone resin is included in an amount of 30% to 80% by weight of the total amount of the first silicone resin, the second silicone resin, the crosslinking agent, the initiator, the inorganic hollow particles, and the fluorine-based leveling agent. Dragon composition.
The method of claim 1, wherein the first silicone resin, the second silicone resin, a crosslinking agent, an initiator, an inorganic hollow particle, a total of fluorine-based leveling agent,
30% to 80% by weight of the first silicone resin,
0.4% to 1.0% by weight of the second silicone resin,
5 to 20% by weight of the crosslinking agent,
1 to 3% by weight of the initiator,
10 to 40% by weight of the inorganic hollow particles,
A composition for a window coating layer comprising 3% to 8% by weight of the fluorine-based leveling agent.
It is a flexible window film comprising a base layer and a coating layer formed on the base layer, wherein the flexible window film has a total light transmittance of 90% or more, a haze of 50% to 80%, a radius of curvature of 5.0 mm or less, and a RIQ of 10 or more. ,
The coating layer is formed of a composition for a window coating layer of any one of claims 1 to 4, 6 to 9, flexible window film.
delete The flexible window film according to claim 10, wherein the base layer has a first base layer and a second base layer laminated with an adhesive.

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