BIAXIALLY ORIENTED POLYPROPYLENE FILM FOR CAPACITOR, METAL FILM LAMINATED FILM, AND FILM CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide a biaxially oriented polypropylene film for capacitor which exhibits excellent withstanding voltage characteristics and reliability at high temperature even in the application for a capacitor for high voltage.SOLUTION: A biaxially oriented polypropylene film for capacitor which contains a polypropylene resin having a thickness (t1) by a micrometer method of 1-3 μm and a mesopentad fraction (mmmm) of 95% or more and less than 98%, and has an orientation parameter PMD in a longitudinal direction and an orientation parameter PTD in a width direction satisfying the following expression (1): 0.80≤PMD+PTD≤0.95. In expression (1), PMD=(A841/A809)/(5.8+(A841/A809)),PTD=(B841/B809)/(5.8+(B841/B809)), A841 is an absorption peak area at a wavelength of 841 cmin FT-IR when having polarized a light source in a longitudinal direction and measured the polarized light source, A809 is an absorption peak area at a wavelength of 809 cmin FT-IR when having polarized a light source in a longitudinal direction and measured the polarized light source, B841 is an absorption peak area at a wavelength of 841 cmin FT-IR when having polarized a light source in a width direction and measured the polarized light source, and B809 is an absorption peak area at a wavelength of 809 cmin FT-IR when having polarized a light source in a width direction and measured the polarized light source.SELECTED DRAWING: None