| 摘要 |
PROBLEM TO BE SOLVED: To provide a porous polyimide film that suppresses development of cracks and is suitable for a cell electrode material such as a cell separator, a separation membrane, a low dielectric constant material, or the like.SOLUTION: The porous polyimide film is obtained through steps of: forming a coating film that contains a polyimide precursor solution prepared by dissolving a polyimide precursor in a water-soluble solvent and contains 0.1 to 5 mass% of non-crosslinking resin particles incapable of dissolving in the solution, and then drying and heating the coating film to imidize to form a polyimide film; and removing the non-crosslinking resin particles by dissolving the particles in an organic solvent to produce pores.SELECTED DRAWING: None |
