Adhesive composition, protective film for a polarizing plate, polarizing plate, and liquid crystal display

A polarizer comprising:

• a polarizing film or polarizing element;
• and
• a protective film attached to a side or both sides of the polarizing film or polarizing element,
• wherein the protective film comprises:
• a base film and
• a pressure sensitive adhesive layer on a side of the base film,
• wherein the polarizing film or polarizing element, the base film and the pressure sensitive adhesive layer are provided in the polarizer in the above order,
• wherein the base film is a cycloolefine polymer film or an acrylic film,
• wherein a stress optical coefficient of the base film is 6 brewster or less and wherein the pressure sensitive adhesive layer is a cured product of a pressure-sensitive adhesive composition satisfying a condition of General Formula 1 given below:
• ΔX≦2 nm, [General Formula 1]
• wherein Δ X represents an absolute value of a phase retardation (Rin) in a surface-direction, the phase retardation being measured by an equation, Rin={(nx−ny)×d}, when a sheet-shaped pressure-sensitive adhesive that has a width of 10 mm and a length of 20 mm and that is prepared by using the pressure-sensitive adhesive composition is elongated by 500 μm in a longitudinal direction at 23° C., wherein nx represents a refractive index along a horizontal axis in a surface of the sheet-shaped pressure-sensitive adhesive, ny represents a refractive index along a vertical axis in the surface of the sheet-shaped pressure-sensitive adhesive, and d represents a thickness of the sheet-shaped pressure-sensitive adhesive.