US Patent 7339736 Light polarizing film

A light polarizing film and method of making same includes a linear polarizer having a first surface and a second surface and having a polarization direction, an optical retarder comprising a simultaneously biaxially oriented polypropylene film disposed adjacent to the first surface of the linear polarizer and having an axis oriented at an angle with respect to the polarization direction, and an adhesive layer disposed between the first surface of the linear polarizer and the optical retarder and having a minimum adhesion strength of about 25 grams per inch.