| 摘要 |
PURPOSE:To obtain a long porous org. film having a large number of fine through-holes having a uniform pore size by uniformly making a large number of through-holes with a diameter of a specific value or less in the whole of a long org. film in specific density or more. CONSTITUTION:A long porous org. film is obtained by passing a long org. film 165 through the gap between a first roll having a large umber of particles having sharp angle parts bonded to the surface thereof and a second roll having a smooth surface. At this time, the pressing force to the long org. film passing through the gap between the rolls is adjusted so as to become uniform over the entire surface of the long org. film 165 coming into contact with the rolls. By this constitution, a large number of through-holes 166 with a diameter of 50 pm or less are made in the whole of the long org. film 165 in density of 500/cm or more. The pore size of the porous org. film is arbitrarily selected within a range of 50mum or less according to a use. |
