| 摘要 |
<p>A microporous film which is produced by cooling a solution comprising a vinylidene fluoride polymer having a weight-average molecular weight of 1x105 or higher and a solvent therefor to form a two-phase gel and comprises a polymer phase comprising the vinylidene fluoride polymer and having pores which have an average pore diameter as measured by the half-dry method of 0.005 to 5 νm and extend from one to the other side of the film, wherein the inner structure is a percolation structure defined by the following(A):(A)a structure which is an isotropic network structure consisting of a polymer phase three-dimensionally branched in random directions and having, surrounded by the polymer phase, interconnecting pores in which the ratio of the maximum pore diameter as measured by the bubble point method to the average pore diameter as measured by the half-dry method is 2.0 or lower.</p> |
