| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyimide porous membrane having high permeability which is used as the battery separator and the microfiltration filter, and its production method. SOLUTION: The polyimide porous membrane has a Gurley number of <=200 s/100 mL, a network structure of a polyimide phase and a space phase which form fine open pores in the interior of the membrane, and a porous structure on both surfaces of the membrane. An organic solvent solution of a polyimide or a polyimide precursor having an intrinsic viscosity of >=2.2 is subjected to solvent substitution-induced viscoelastic phase separation to allow the polymer component to deposit and rendering the resulting deposit porous. |
