Adhesive film for polarizing plate, polarizing plate including the same and optical display including the same

An adhesive film for polarizing plates, the adhesive film:

• being prepared from an adhesive composition including an isocyanate crosslinking agent, an imide crosslinking agent, a first (meth)acrylic copolymer, and a second (meth)acrylic copolymer, and
• having a ΔG′ of about 50% to about 80%, ΔG′ being represented by Equation 1:
• ΔG′=(G1−G2)/G1×100 [Equation 1]
• wherein G1 is a storage modulus of the adhesive film for polarizing plates as measured at 25° C., and G2 is a storage modulus of the adhesive film for polarizing plates as measured at 85° C., and
• wherein:
• the isocyanate crosslinking agent and the imide crosslinking agent are included together in the composition in an amount of 1.1 parts by weight to 6 parts by weight, based on 100 total parts by weight of the first (meth)acrylic copolymer and the second (meth)acrylic copolymer,
• the first (meth)acrylic copolymer is a copolymer of a monomer mixture including:
• about 65 wt % to about 90 wt % of an alkyl group-containing (meth)acrylic monomer,
• about 0.1 wt % to about 5 wt % of a hydroxyl group-containing (meth)acrylic monomer,
• about 1 wt % to about 15 wt % of an aromatic group-containing (meth)acrylic monomer, and
• about 1 wt % to about 20 wt % of a nitrogen-containing vinyl monomer, and
• the second (meth)acrylic copolymer is a copolymer of a monomer mixture including:
• about 50 wt % to about 90 wt % of an alkyl group-containing (meth)acrylic monomer,
• about 0.1 wt % to about 5 wt % of a hydroxyl group-containing (meth)acrylic monomer,
• about 1 wt % to about 20 wt % of an aromatic group-containing (meth)acrylic monomer, and
• about 1 wt % to about 20 wt % of a nitrogen-containing vinyl monomer.