Polarizing plate and image display device comprising same
The present invention relates to a polarizing plate including: a polarizer; and a protective layer formed on at least one surface of the polarizer, in which the protective layer is a cured product of a radical curable composition including: (A) a radical polymerizable compound having at least one hydrophilic functional group in a molecule thereof; (B) a phosphate-based compound having three (meth)acryl groups in a molecule thereof; and (C) a radical initiator, and an image display device including the same.
1. A polarizing plate comprising:
a polarizer; and
a protective layer formed on at least one surface of the polarizer,
wherein the protective layer is a cured product of a radical curable composition including: (A) a radical polymerizable compound having at least one hydrophilic functional group in a molecule thereof; (B) a phosphate-based compound having three (meth)acryl groups in a molecule thereof; and (C) a radical initiator.
2. The polarizing plate of claim 1 , wherein the radical curable composition comprises: 40 to 93 parts by weight of (A) the radical polymerizable compound; 1 to 40 parts by weight of (B) the phosphate-based compound; and 0.5 to 20 parts by weight of the radical initiator, based on 100 parts by weight of the radical curable composition.
3. The polarizing plate of claim 1 , wherein (A) the radical polymerizable compound is a mixture of (a-1) a radical polymerizable first compound comprising at least one hydroxy group and at least one (meth)acryl group in a molecule thereof and (a-2) a radical polymerizable second compound comprising at least two hydroxy groups, at least one benzene ring or cyclohexane ring, and at least two (meth)acryl groups in a molecule thereof.
4. The polarizing plate of claim 3 , wherein (a-1) the first compound is one or more selected from the group consisting of the following [Formula 1] to [Formula 21]:
5. The polarizing plate of claim 3 , wherein (a-2) the second compound is one or more selected from the group consisting of the following [Formula 22] to [Formula 24]:
6. The polarizing plate of claim 1 , wherein (B) the phosphate-based compound is a compound represented by the following [Formula I]:
in [Formula 1], R 1 , R 2 and R 3 are each independently a substituted or unsubstituted C 1˜10 alkylene group, a substituted or unsubstituted C 4˜14 cycloalkylene group, a substituted or unsubstituted C 6˜14 arylene group, or a combination thereof; R 4 , R 5 and R 6 are each independently hydrogen or a methyl group; and X 1 , X 2 and X 3 are each independently O (oxygen) or N (nitrogen).
7. The polarizing plate of claim 1 , wherein the radical curable composition further comprises (D) a phosphate-based compound having one or two (meth)acryl groups in a molecule thereof.
8. The polarizing plate of claim 7 , wherein (D) the phosphate-based compound is comprised in an amount of 5 to 40 parts by weight based on 100 parts by weight of the polarizing plate.
9. The polarizing plate of claim 7 , wherein (D) the phosphate-based compound is one or more selected from the group consisting of compounds represented by the following [Formula II] and [Formula III]:
in [Formula III], R 7 and R 8 are each independently a substituted or unsubstituted C 1˜10 alkylene group, a substituted or unsubstituted C 4˜14 cycloalkylene group, a substituted or unsubstituted C 6˜14 arylene group, or a combination thereof; R 9 and R 10 are each independently hydrogen or a methyl group; and X 4 and X 5 are each independently O(oxygen) or N (nitrogen),
in [Formula III], R 11 is a substituted or unsubstituted C 1˜10 alkylene group, a substituted or unsubstituted C 4˜14 cycloalkylene group, a substituted or unsubstituted C 6˜14 arylene group, or a combination thereof; R 12 is each independently hydrogen or a methyl group; and X 6 is each independently O (oxygen) or N (nitrogen).
10. The polarizing plate of claim 1 , wherein the radical curable composition further comprises (E) a polyfunctional (meth)acrylic compound.
11. The polarizing plate of claim 10 , wherein (E) the polyfunctional (meth)acrylic compound is comprised in an amount of 5 to 40 parts by weight based on 100 parts by weight of the polarizing plate.
12. The polarizing plate of claim 10 , wherein (E) the polyfunctional (meth)acrylic compound is one or more selected from the group consisting of compounds represented by the following [Formula IV] to [Formula VI]:
in [Formula IV], R 13 and R 14 are each independently a (meth)acryloyloxy group or a (meth)acryloyloxy alkyl group,
in [Formula V], R 15 , R 16 and R 17 are each independently a (meth)acryloyloxy group, or a (meth)acryloyloxy alkyl group, and R 18 is a (meth)acryloyloxy group, a (meth)acryloyloxy alkyl group, a hydroxy group, or a substituted or unsubstituted C 1˜10 alkyl group,
in [Formula VI], R 19 is a substituted or unsubstituted C 1˜10 alkylene, and R 20 and R 21 are each independently a (meth)acryloyloxy group or a (meth)acryloyloxy alkyl group.
13. The polarizing plate of claim 1 , wherein the radical curable composition has a glass transition temperature of 50° C. or more after curing.
14. The polarizing plate of claim 1 , wherein the radical curable composition has a viscosity of 70 cP or less.
15. The polarizing plate of claim 1 , wherein the protective film has a thickness of 0.5 to 20 μm.
16. The polarizing plate of claim 1 , wherein a protective film is attached to a surface opposite to a surface of the polarizer, on which the protective layer is formed, through an adhesive layer.
17. The polarizing plate of claim 1 , further comprising: an adhesion layer at an upper portion of the protective layer.
18. An image display device comprising the polarizing plate of claims 1 .