APPARATUS AND METHOD OF PRODUCING POROUS MEMBRANES

摘要

The present invention relates to an apparatus and method of producing lengths of multi-layered asymmetric membrane (10) by way of extruding different feedstock through a die head (46,78) having a plurality of outlet ports. The membrane (10) includes a plurality of apertures extending therethrough, and at least some of said apertures increase in cross-sectional area from a first surface of the membrane to a second surface of the membrane. The present invention provides a method of constructing membrane in desired lengths and reduces the need to weld portions of membrane together to produce extended lengths of membrane tube.