Conductive polymer film and polarizing plate using the same

A method of producing a protective film for a polarizing plate comprising a polymer film and a conductive polymer layer adhered to the surface thereof:

• comprising the steps of:
• forming an aqueous coating liquid comprising a conductive polymer by mixing polythiophene or polythiophene derivatives with water, and
• forming the conductive polymer layer with the aqueous coating liquid on the surface of the polymer film, wherein
• the polymer film comprises a norbornene material,
• the conductive polymer layer has a thickness of 3 μm or less,
• the protective film has a visible light transmission of 78% or more and a surface resistivity of 103-1012 Ω/square, and
• a yellowness of the protective film is decreased rather than a yellowness of the polymer film comprising a norbornene material by the forming of the conductive polymer layer on the surface of the polymer film.