Polarizing plate and optical display comprising the same
A polarizing plate and an optical display including the same are provided. A polarizing plate includes: a polarizer; a bonding layer on an upper surface of the polarizer; and an anti-reflection film on an upper surface of the bonding layer, and the anti-reflection film includes a base layer, a high refractivity layer, and a low refractivity layer sequentially stacked on the bonding layer in the stated order, the bonding layer has an index of refraction of about 1.51 to less than 1.60, and the polarizer, the bonding layer, and the base layer satisfy the relation: Index of refraction of polarizer<Index of refraction of bonding layer<Index of refraction of base layer.
1. A polarizing plate comprising:
a polarizer;
a bonding layer on an upper surface of the polarizer; and
an anti-reflection film on an upper surface of the bonding layer,
wherein the anti-reflection film comprises a base layer, a high refractivity layer, and a low refractivity layer sequentially stacked on the bonding layer in the stated order,
the bonding layer having an index of refraction of about 1.51 to less than 1.60, and
the polarizer, the bonding layer, and the base layer satisfying the following Relation 1:
Index of refraction of polarizer<Index of refraction of bonding layer<Index of refraction of base layer.
2. The polarizing plate according to claim 1 , wherein the anti-reflection film has a reflectivity of about 0.3% or less.
3. The polarizing plate according to claim 1 , wherein the base layer has a higher index of refraction than the low refractivity layer, and a difference in index of refraction between the base layer and the low refractivity layer is about 0.25 or more.
4. The polarizing plate according to claim 1 , wherein the base layer has an index of refraction of about 1.60 or more.
5. The polarizing plate according to claim 1 , wherein the base layer comprises a film formed of at least one of polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate.
6. The polarizing plate according to claim 1 , wherein the high refractivity layer has an index of refraction of about 1.65 or more.
7. The polarizing plate according to claim 1 , wherein the low refractivity layer has an index of refraction of less than about 1.65.
8. The polarizing plate according to claim 1 , wherein the bonding layer is formed of a bonding layer composition comprising an epoxy compound and an initiator.
9. The polarizing plate according to claim 8 , wherein the bonding layer composition further comprises at least one of a (meth)acrylate compound and an oxetane compound.
10. The polarizing plate according to claim 1 , wherein the bonding layer is formed of a bonding layer composition comprising about 50 wt % to about 80 wt % of an alicyclic epoxy compound, about 1 wt % to about 20 wt % of an aromatic epoxy compound, about 1 wt % to about 20 wt % of a (meth)acrylate compound having at least one hydrophilic group, about 1 wt % to about 20 wt % of a (meth)acrylate compound having no hydrophilic group, and about 1 wt % to about 10 wt % of an initiator in terms of solid content.
11. The polarizing plate according to claim 1 , wherein the bonding layer is formed of a bonding layer composition comprising about 30 wt % to about 70 wt % of an aromatic epoxy compound, about 10 wt % to about 50 wt % of a linear aliphatic epoxy compound, about 10 wt % to about 40 wt % of an oxetane compound, and about 1 wt % to about 10 wt % of an initiator in terms of solid content.
12. The polarizing plate according to claim 1 , wherein the polarizer has an index of refraction of about 1.3 to about 1.5, the bonding layer has an index of refraction of about 1.51 to about 1.59, the base layer has an index of refraction of about 1.60 to about 1.75, the high refractivity layer has an index of refraction of about 1.65 to about 1.80, and the low refractivity layer has an index of refraction of about 1.1 to about 1.5.
13. The polarizing plate according to claim 1 , wherein the anti-reflection film further comprises a hard coating layer between the base layer and the high refractivity layer.
14. The polarizing plate according to claim 13 , wherein the anti-reflection film has a reflectivity of about 0.3% or less.
15. The polarizing plate according to claim 13 , wherein the base layer has a higher index of refraction than the hard coating layer, and a difference in index of refraction between the base layer and the hard coating layer is about 0.05 or more.
16. The polarizing plate according to claim 13 , wherein the polarizer has an index of refraction of about 1.3 to about 1.5, the bonding layer has an index of refraction of about 1.51 to about 1.59, the base layer has an index of refraction of about 1.60 to about 1.75, the hard coating layer has an index of refraction of about 1.50 to about 1.599, the high refractivity layer has an index of refraction of about 1.65 to about 1.80, and the low refractivity layer has an index of refraction of about 1.1 to about 1.5.
17. The polarizing plate according to claim 1 , wherein the anti-reflection film further comprises a support layer between the base layer and the high refractivity layer.
18. The polarizing plate according to claim 1 , further comprising a polarizer protective film on a lower surface of the polarizer.
19. The polarizing plate according to claim 1 , wherein the polarizing plate has a reflectivity of about 0.4% or less, as measured at a side of the low refractivity layer.
20. An optical display comprising the polarizing plate according to claim 1 .