Antireflection film
The present invention relates to an antireflection film being capable of realizing high scratch resistance and antifouling property while simultaneously having low reflectivity and high light transmittance, and further being capable of enhancing screen sharpness of a display device.
1. An antireflection film comprising:
a hard coating layer or an antiglare layer; and
a low refractive index layer formed on one side of the hard coating layer or the antiglare layer, wherein the low refractive index layer includes a binder resin, and hollow silica nanoparticles, metal oxide nanoparticles, and inorganic nanoparticles dispersed in the binder resin,
wherein a first region containing the hollow silica nanoparticles, a second region containing the metal oxide nanoparticles, and a third region containing the inorganic nanoparticles are present in the low reflective index layer, and
wherein the second region contained in the low refractive index layer has polarization ellipticity measured by an ellipsometry method using a Cauchy model represented by the following General Formula 1, in which A is 1.53 to 3.0, B is 0 to 0.1 nm 2 , and C is 0 to 1*10 −2 nm 4 :
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.
2. The antireflection film of claim 1 , wherein, the first region contained in the low refractive index layer has the polarization ellipticity measured by the ellipsometry method using a Cauchy model represented by the following General Formula 1, in which A is 1.0 to 1.45, B is 0 to 0.1 nm 2 , and C is 0 to 1*10 −2 nm 4 :
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.
3. The antireflection film of claim 1 , wherein, the third region contained in the low refractive index layer has the polarization ellipticity measured by the ellipsometry method using a Cauchy model represented by the following General Formula 1, in which A is 1.0 to 1.8, B is 0 to 0.01 nm 2 , and C is 0 to 1*10 −2 nm 4 :
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 polarization ellipticity measured by the ellipsometry method is determined by carrying out the ellipticity measurement at an incident angle of 70° over a wavelength range of 380 nm to 1000 nm.
5. The antireflection film of claim 1 , wherein the first region, the second region, and the third region satisfy the following General Formula 2:
[General Formula 2]
Refractive Index (n1) of First Region<Refractive Index (n3) of Third Region<Refractive Index (n2) of Second Region
wherein n1, n2, and n3 are refractive indexes obtained by carrying out the ellipsometry measurement at an incident angle of 70° over a wavelength range of 380 nm to 1000 nm.
6. The antireflection film of claim 1 , wherein
the first region includes 70% by volume or more of the entire hollow silica nanoparticles, the second region includes 70% by volume or more of the entire metal oxide nanoparticles, and the third region includes 70% by volume or more of the entire inorganic nanoparticles.
7. The antireflection film of claim 1 , wherein in the low refractive index layer, the third region is located closer to an interface between the hard coating layer or the antiglare layer and the low refractive index layer, compared to the second region, and the second region is located closer to an interface between the hard coating layer or the antiglare layer and the low refractive layer, compared to the first region.
8. The antireflection film of claim 1 , wherein
the first region, the second region, and the third region in the low refractive index layer are present in a continuous phase by one binder resin.
9. The antireflection film of claim 1 , wherein
the low refractive index layer is obtained by coating with a resin composition comprising a binder resin, a hollow silica nanoparticle, a metal oxide nanoparticle, and an inorganic nanoparticle.
10. The antireflection film of claim 1 , wherein
the average diameter of the hollow silica nanoparticle, the metal oxide nanoparticle, and the inorganic nanoparticle satisfies the following General Formula 3:
[General Formula 3]
Average Diameter of Inorganic Nanoparticles<Average Diameter of Metal Oxide Nanoparticles<Average Diameter of Hollow Silica Nanoparticles.
11. The antireflection film of claim 1 , wherein
the ratio of the average diameter of the inorganic nanoparticles to the average diameter of the metal oxide nanoparticles is 0.5 to 0.9.
12. The antireflection film of claim 1 , wherein
the ratio of the average diameter of the inorganic nanoparticles to the average diameter of the hollow silica nanoparticles is 0.01 to 0.5.
13. The antireflection film of claim 1 , wherein
the refractive index of the first region is less than 1.4, the refractive index of the second region is more than 1.55, and the refractive index of the third region is more than 1.4 and less than 1.55.
14. The antireflection film of claim 1 , wherein
the thicknesses of the first region, the second region, and the third region are respectively 10 nm to 200 nm.
15. The antireflection film of claim 1 , wherein
the antireflection film exhibits average reflectivity of 0.3% or less in the visible light wavelength band of 380 nm to 780 nm.
16. The antireflection film of claim 1 , wherein
the binder resin contained in the low refractive index layer includes a (co)polymer of a photopolymerizable compound and a fluorine-containing compounds containing a photoreactive functional group, and the fluorine-containing compound containing the photoreactive functional group has a weight average molecular weight of 2000 to 200,000.
17. The antireflection film of claim 16 , wherein
the binder resin includes 20 parts by weight to 300 parts by weight of the fluorine-containing compound containing the photoreactive functional group based on 100 parts by weight of the (co)polymer of a photopolymerizable compound.
18. The antireflection film of claim 16 , wherein
the fluorine-containing compound containing the photoreactive functional group includes at least one reactive functional group 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 for at least one carbon; ii) a heteroaliphatic compound or 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 for 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.
19. The antireflection film of claim 1 , wherein
the hard coating layer or the antiglare layer includes: a binder resin including a photocurable resin; and an antistatic agent dispersed in the binder resin.
20. The antireflection film of claim 19 , wherein the hard coating layer or the antiglare layer further includes at least one compound selected from the group consisting of an alkoxysilane-based oligomer and a metal alkoxide-based oligomer.