Radically curable adhesive composition and polarizing plate including the same

1. A radically curable adhesive composition comprising, based on 100 parts by weight thereof,

40 to 80 parts by weight of a first compound represented by the following Formula 1;

15 to 50 parts by weight of a second compound comprising at least one carboxy group; and

0.5 to 10 parts by weight of a radical initiator,

where R 1 is an ester group or an ether group,

R 2 is a C 1-10 alkyl group comprising at least one hydroxy substituent or a C 4-10 cycloalkyl group comprising at least one hydroxy substituent, and

R 3 is hydrogen or a C 1-10 alkyl group.

2. The radically curable adhesive composition of claim 1 , wherein the radically curable adhesive composition comprises 50 to 70 parts by weight of the first compound, 20 to 40 parts by weight of the second compound, and 0.5 to 10 parts by weight of the radical initiator, based on 100 parts by weight the radically curable adhesive composition.

3. The radically curable adhesive composition of claim 1 , further comprising, as a third compound, an acrylic monomer having a ring structure with a carbon number of 7 to 20.

4. The radically curable adhesive composition of claim 3 , wherein the radically curable adhesive composition comprises 40 to 80 parts by weight of the first compound, 15 to 50 parts by weight of the second compound, 1 to 50 parts by weight of the third compound, and 0.5 to 10 parts by weight of the radical initiator, based on 100 parts by weight the radically curable adhesive composition.

5. The radically curable adhesive composition of claim 1 , wherein the first compound comprises at least one selected from the group consisting of compounds represented by the following Formulas 2 to 11:

6. The radically curable adhesive composition of claim 1 , wherein the second compound has an acidity of 100 to 1,000 KOH mg/g.

7. The radically curable adhesive composition of claim 1 , wherein the second compound comprises at least one selected from the group consisting of compounds represented by the following Formulas 12 to 26:

where R′ is

and n is an integer ranging from 1 to 5

8. The radically curable adhesive composition of claim 3 , wherein the third compound comprises at least one selected from the group consisting of isobornyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate), and 1-adamantyl-(meth)acrylate.

9. The radically curable adhesive composition of claim 1 , further comprising a cationic initiator.

10. The radically curable adhesive composition of claim 9 , wherein the cationic initiator is included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the radically curable adhesive composition.

11. The radically curable adhesive composition of claim 9 , wherein the cationic initiator comprises at least one selected from the group consisting of hexafluoroantimonate, diphenyl(4-phenylthio)phenylsulfonium hexafluorophosphate, (phenyl)[4-(2-methylpropyl) phenyl]-iodonium hexafluorophosphate, (thiodi-4,1-phenylene)bis(diphenylsulfonium) dihexafluoroantimonate, and (thiodi-4,1-phenylene)bis(diphenylsulfonium)dihexafluorophosphate.

12. The radically curable adhesive composition of claim 1 , wherein the radically curable adhesive composition has an acidity of 30 to 300 mg KOH/g.

13. The radically curable adhesive composition of claim 1 , wherein the radically curable adhesive composition has a glass transition temperature of 70° C. or higher.

14. The radically curable adhesive composition of claim 1 , wherein the radically curable adhesive composition has a viscosity of 10 to 300 cP.

15. A polarizing plate comprising:

a polarizer;

an adhesive layer formed on at least one surface of the polarizer; and

an acrylic protective film formed on the adhesive layer,

wherein the adhesive layer is formed of the radically curable adhesive composition of claim 1 .