FLAT PERMEABLE POLYOLEFIN MEMBRANES

摘要

A flat permeable polyolefin membrane 10 to 500 mu m in thickness, which has in one surface thereof a compact layer formed of intimately bound fine polyolefin particles and possessed of fine pores and in the interior and the other surface thereof a layer formed of an aggregate of fine discrete polyolefin particles of an average diameter in the range of 0.01 to 5 mu m so adjoined as to form fine labyrinthically continuing through pores and which, therefore, establishes communication between the opposite surfaces of said membrane.