Patent ID: 8202610

Claim:
A protective film for a polarizing plate comprising k layers (k is an integer of 2 or more) of thermoplastic resin laminated, wherein the protective film is obtained by coextrusion, and the refractive index n i (380) at the wavelength of 380 nm and refractive index n i (780) at the wavelength of 780 nm in the i th thermoplastic resin layer as well as refractive index n i+1 (380) at the wavelength of 380 nm and refractive index n i+1 (780) at the wavelength of 780 nm in the i+1 th thermoplastic resin layer have a relationship in Formula [1], wherein the i th thermoplastic resin is different from the i+1 th thermoplastic resin, ∥ n i (380)− n i+1 (380)|−| n i (780)− n i+1 (780)∥≦0.02 Formula [1] (i is an integer from 1 to k−1).