Polarizing plate
Provided are a polarizing plate and a liquid crystal display device. The polarizing plate has lighter weight, a smaller thickness, and excellent physical properties such as water resistance, workability, durability, and light leakage preventing ability. In addition, the polarizing plate prevents curling occurring at the polarizing plate or a polarizer in formation thereof, and has excellent thermal resistance or thermal shock resistance.
1. A polarizing plate, comprising:
a polarizer;
an active energy beam-curable adhesive layer having a thickness of 0.1 to 30 μm; and
a pressure-sensitive adhesive layer having first and second surfaces and a thickness of 10 to 80 μm, which are sequentially disposed,
wherein the active energy beam-curable adhesive layer includes an adhesive composition including an epoxy compound and an acryl-based monomer in a cured state, and having a glass transition temperature after curing of 50° C. or more,
wherein the active energy beam-curable adhesive layer is directly attached to at least one surface of the polarizer, and the pressure-sensitive adhesive layer is directly attached to the active energy beam-curable adhesive layer,
wherein the first surface has a higher tensile modulus than the second surface, and the first surface is directly attached to the active energy beam-curable adhesive layer, and
wherein the first surface has a tensile modulus at 25° C. of 100 to 1,000 MPa and the second surface has a tensile modulus at 25° C. of 0.01 to 0.5 MPa,
wherein the pressure-sensitive adhesive layer comprises a first pressure-sensitive adhesive layer forming the first surface and a second pressure-sensitive adhesive layer forming the second surface, wherein the first pressure-sensitive adhesive layer comprises a crosslinking structure of an acryl polymer crosslinked by a multifunctional crosslinking agent and a crosslinking structure of polymerized multifunctional acrylate and wherein the second pressure-sensitive adhesive layer is formed from a heat-curable or room temperature-curable pressure-sensitive adhesive composition and comprises an acryl polymer crosslinked by a multifunctional crosslinking agent.
2. The polarizing plate according to claim 1 , wherein the epoxy compound is crosslinked or polymerized by a cationic reaction and wherein the adhesive composition further includes a cationic initiator.
3. The polarizing plate according to claim 2 , wherein the acryl-based monomer is a radical polymerizable compound and wherein the adhesive composition further includes a photoinitiator as a radical initiator.