摘要 |
A biaxially stretched polypropylene film for capacitors, which has projections on both surfaces and has a thickness (t1) of 1-3 mum. This biaxially stretched polypropylene film for capacitors satisfies all of the formulae (1)-(4) described below, if one surface of the film is taken as a surface A and the other surface of the film is taken as a surface B. Provided are: a biaxially stretched polypropylene film which exhibits excellent withstand voltage properties, security and reliability in applications as capacitors for high voltage, while ensuring stable element processability; a metallized film; and a film capacitor. |Pa - Pb| >= 200 (1) 0.350 <= Pa/SRzA <= 0.700 (2) 500 nm <= SRzA <= 1,200 nm (3) 50 nm <= SRzB < 500 nm (4) In this connection, Pa represents the number of projections per 0.1 mm2 of the surface A; Pb represents the number of projections per 0.1 mm2 of the surface B; SRzA represents the ten-point average roughness of the surface A; and SRzB represents the ten-point average roughness of the surface B. |