Polarizing Plate and Image Display Device Comprising Same

1 . A polarizing plate comprising:

a polarizer; and

a protective layer is on one surface or both surfaces of the polarizer directly adjoining the polarizer,

wherein the protective layer is a cured material of a photocurable composition for a polarizing plate protective layer comprising an epoxy compound and an oxetane-based compound, and in a spectrum by Fourier transform infrared spectroscopy (FTIR) of the protective layer, the following Equation 1 is satisfied:

0.9

≤

I

e

I

a

+

I

e

[

Equation





1

]

in Equation 1,

I e is a ratio of peak intensity at 920 cm −1 to 900 cm −1 with respect to peak intensity at 1740 cm −1 to 1700 cm −1 in the spectrum by Fourier transform infrared spectroscopy (FTIR) of the protective layer; and

I a is peak intensity at 1420 cm −1 to 1380 cm −1 with respect to peak intensity at 1740 cm −1 to 1700 cm −1 in the spectrum by Fourier transform infrared spectroscopy (FTIR) of the protective layer.

2 . The polarizing plate of claim 1 , wherein the protective layer has a thickness of 4 μm to 11 μm.

3 . The polarizing plate of claim 1 , wherein the protective layer has a thermal expansion coefficient of 100 ppm/K or less at 80° C.

4 . The polarizing plate of claim 1 , wherein the protective layer has a glass transition temperature (Tg) of higher than or equal to 90° C. and lower than or equal to 170° C.

5 . The polarizing plate of claim 1 , wherein the protective layer has a storage modulus of 1,500 MPa or greater at 80° C.

6 . The polarizing plate of claim 1 , wherein the protective layer has a tensile modulus of 1,700 MPa or greater at 25° C.

7 . The polarizing plate of claim 1 , wherein, when leaving the polarizing plate unattended for 4 hours or longer at 80° C., a contractile force in any one or more of an absorption axis direction (MD direction) and a transmission axis direction (TD direction) is from 3 N to 10N.

8 . The polarizing plate of claim 1 , wherein the polarizing plate satisfies the following Equation A:

0.01



<

¯



L

c

-

L

e

L

i



<

¯



1

[

Equation





A

]

in Equation A,

L c is a contractile force of a region corresponding to a circle area with a diameter of 1 cm having the center of the polarizing plate as the origin;

L e is a polarizing plate contractile force of a region corresponding to a circle area with a diameter of 1 cm adjoining two edge portions meeting at each vertex of the polarizing plate; and

L i is an average contractile force in an absorption axis direction (MD direction) or a transmission axis direction (TD direction) of the polarizer; or an average contractile force in an absorption axis direction (MD direction) or a transmission axis direction (TD direction) of the polarizing plate.

9 . The polarizing plate of claim 1 , wherein the epoxy compound comprises an alicyclic epoxy compound.

10 . The polarizing plate of claim 1 , wherein the epoxy compound and the oxetane-based compound have a weight ratio of 9:1 to 1:9.

11 . The polarizing plate of claim 1 , comprising:

wherein the protective layer is on one surface of the polarizer, and

the polarizing plate further comprises a protective film attached on a surface opposite to the protective layer on the one surface of the polarizer by an adhesive layer,

wherein the protective film has a tensile modulus of 1700 MPa or greater at 25° C.

12 . The polarizing plate of claim 1 , wherein the protective layer is on both surfaces of the polarizer.

13 . The polarizing plate of claim 1 , further comprising a gluing layer on a surface opposite to a surface facing the polarizer of the protective layer.

14 . An image display device comprising the polarizing plate of claim 1 .