BIAXIALLY ORIENTED POLYESTER FILM AND ROLL

摘要

PROBLEM TO BE SOLVED: To provide a biaxially oriented polyester film in which in the case of winding the same into a roll shape, a winding form is good and also a roll holding quality and a quality level for a long period is obtained. SOLUTION: The biaxially oriented polyester film is provided with projections formed by a processing roll for forming the projections, on at least one side in the vicinities of both end parts in the cross direction. The ratio of the area defined by vertically projecting the parts 4 deformed by the above-mentioned processing roll for forming the projections on the face of the film to the area of the part 5 of the film getting into contact with the processing roll for forming the projections is regulated to 0.01-0.25.