Antireflection film comprising a low refractive index layer and a hard coating layer

1. An antireflection film comprising: a low refractive index layer and a hard coating layer, wherein the low refractive index layer includes a binder resin containing a crosslinked polymer of a photopolymerizable compound and a polysilsesquioxane substituted with one or more reactive functional groups and inorganic fine particles dispersed in the binder resin;

wherein a ratio of internal haze (Hi) to total haze (Ha) of the antireflection film is 97% or less, and

a variation in color coordinate value V) of the antireflection film before and after alkali treatment is 0.7 or less.

2. The antireflection film of claim 1 , wherein

the variation in the color coordinate value (b*) of the antireflection film before and after the alkali treatment is determined by measuring the color coordinate values of the antireflection film before and after the alkali treatment in which the antireflection film is immersed for 1 second to 100 seconds in an aqueous alkaline solution diluted to 5 to 50% with distilled water.

3. The antireflection film of claim 1 , wherein

the low reflective index layer has polarization ellipticity measured by an ellipsometry method using a Cauchy model of the following General Formula 1 in which A is 1.20 to 1.65, B is 0 to 0.05, and C is 0 to 0.05:

n

⁡

(

λ

)

=

A

+

B

λ

2

+

C

λ

4

[

General

⁢

⁢

Formula

⁢

⁢

1

]

wherein, in the above General Formula 1, n(λ) is a refractive index at a wavelength λ, λ is in a range of 300 nm to 1800 nm, and A, B, and C are Cauchy parameters.

4. The antireflection film of claim 1 , wherein

the hard coating layer has polarization ellipticity measured by an ellipsometry method using a Cauchy model of the following General Formula 1,

in which A is 1.30 to 1.75, B is 0 to 0.05, and C is 0 to 0.005:

n

⁡

(

λ

)

=

A

+

B

λ

2

+

C

λ

4

[

General

⁢

⁢

Formula

⁢

⁢

1

]

wherein, in the above General Formula 1, n(λ) is a refractive index at a wavelength λ, λ is in a range of 300 nm to 1800 nm, and A, B, and C are Cauchy parameters.

5. The antireflection film of claim 1 , wherein the reflective index layer has a thickness of 1 nm to 200 nm, and the hard coating layer has a thickness of 0.1 μm to 100 μm.

6. The antireflection film of claim 1 , wherein a weight ratio of a portion derived from the polysilsesquioxane substituted with one or more reactive functional groups to a portion derived from the photopolymerizable compound in the binder resin contained in the low reflective index layer is 0.005 to 0.50.

7. The antireflection film of claim 1 , wherein the functional group substituted on the polysilsesquioxane includes at least one functional group selected from the group consisting of an alcohol, an amine, a carboxylic acid, an epoxide, an imide, a (meth)acrylate, a nitrile, a norbornene, an olefin, polyethylene glycol, a thiol, and a vinyl group.

8. The antireflection film of claim 1 , wherein at least one silicon atom of the polysilsesquioxane is substituted with a reactive functional group, and remaining silicon atoms not substituted with the reactive functional groups are substituted with unreactive functional groups.

9. The antireflection film of claim 8 , wherein the polysilsesquioxane substituted with one or more reactive functional groups includes a polyhedral oligomeric silsesquioxane having a cage structure, in which one or more functional groups are substituted.

10. The antireflection film of claim 1 , wherein the photopolymerizable compound includes a monomer or an oligomer containing a (meth)acrylate or vinyl group.

11. The antireflection film of claim 1 , wherein the binder resin further includes a crosslinked polymer of a photopolymerizable compound, a fluorine-based compound containing a photoreactive functional group, and polysilsesquioxane substituted with one or more reactive functional groups.

12. The antireflection film of claim 11 , wherein the photoreactive functional group contained in the fluorine-based compound is at least one selected from the group consisting of a (meth)acrylate group, an epoxide group, a vinyl group, and a thiol group.

13. The antireflection film of claim 11 , wherein the fluorine-based compound containing photoreactive functional group has a fluorine content of 1% by weight to 60% by weight.

14. The antireflection film of claim 11 , wherein the fluorine-based compound containing the photoreactive functional group includes at least one selected from the group consisting of: i) an aliphatic compound or an aliphatic cyclic compound in which at least one photoreactive functional group is substituted and at least one fluorine is substituted on at least one carbon; ii) a heteroaliphatic compound or a heteroaliphatic cyclic compound in which at least one photoreactive functional group is substituted, at least one hydrogen is substituted with fluorine, and at least one carbon is substituted with silicon; iii) a polydialkylsiloxane-based polymer in which at least one photoreactive functional group is substituted and at least one fluorine is substituted on at least one silicon; and iv) a polyether compound in which at least one photoreactive functional group is substituted and at least one hydrogen is substituted with fluorine.

15. The antireflection film of claim 11 , wherein the fluorine-based compound containing the photoreactive functional group has a weight-average molecular weight of 2000 to 200,000.

16. The antireflection film of claim 1 , wherein the inorganic fine particles include at least one selected from the group consisting of solid inorganic nanoparticles having a diameter of 0.5 to 100 nm, and hollow inorganic nanoparticles having a diameter of 1 to 200 nm.

17. The antireflection film of claim 1 , wherein the hard coating film includes a binder resin containing a photopolymerizable resin and a high molecular weight (co)polymer having a weight average molecular weight of 10,000 or more, and an organic or inorganic fine particle dispersed in the binder resin.