| 摘要 |
A biaxially stretched polypropylene film for capacitors, which has protrusions on both surfaces and has a thickness (t1) of 1-3 µm. 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 withstanding voltage properties, security and reliability in applications as capacitors for high voltage, while ensuring stable element processability; a metallized film; and a film capacitor; Formula (1) |Pa - Pb| ‰¥ 200; Formula (2) 0.350 ‰¤ Pa/SRzA ‰¤ 0.700; Formula (3) 500 nm ‰¤ SRzA ‰¤ 1,200 nm; Formula (4) 50 nm ‰¤ SRzB < 500 nm. In this connection, Pa represents the number of protrusions per 0.1 mm 2 of the surface A; Pb represents the number of protrusions per 0.1 mm 2 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. |
