| 摘要 |
PURPOSE:To obtain the title film having non-linear through-holes with very long cavities readily, by heat-treating a multi-layer laminate of fibrous webs consisting mainly of a thermoplastic fibrous polymer under specific conditions to increase the apparent density. CONSTITUTION:At least five layers of fibrous webs consisting mainly of a thermoplastic fibrous polymer are laminated and heat-treated with both edges held and out of contact with other materials to melt at least 50 wt.% of the polymer. The resulting laminate has an apparent density of 0.40-0.99, a filmy appearance without fibrous shape, a structure very similar to that of the skin of a living tissue, etc., and ideal functions to separate and permeate substances of the order of microns. |
