BIAXIALLY ORIENTED POLYPROPYLENE FILM FOR CAPACITOR, METALLIZED FILM, AND FILM CAPACITOR

摘要

The present invention aims to provide a biaxially orientated polypropylene film for capacitor that ensures a high withstand voltage and reliability at high temperatures as well as stable element processability when applied to high voltage capacitors. The present invention provides a biaxially orientated polypropylene film for capacitor having protrusions on both surfaces, having a thickness (t1) of 1 to 3 µm, having a ten point average roughness (SRz) of 50 nm or more and less than 500 nm on both surfaces, and meeting both equations (1) and (2) given below where one surface and the other surface are referred to as a surface A and a surface B, respectively. 150 ‰¤ Pa ‰¤ 400 50 ‰¤ Pb ‰¤ 150
(In equations (1) and (2) given above, Pa denotes the number of protrusions per 0.1 mm 2 on the surface A and Pb denotes the number of protrusions per 0.1 mm 2 on the surface B.)