Patent ID: 9266066
Filing Date: 2016-02-23
CPC Classification: B01D,B29C,B29K

Claim Text:
1. An asymmetric microporous membrane comprising a first surface and a second surface, an interior bulk defined by the first and second surfaces, and a first asymmetric section and a second asymmetric section, wherein the first surface has at least a first portion and a second portion, the first asymmetric section comprising the first portion having a first porosity extending from the first portion into the interior bulk, the interior bulk having a first asymmetric pore structure, the first porosity comprising a first mean pore size, and the second asymmetric section comprising the second portion having a second porosity extending from the second portion into the interior bulk, the interior bulk having a second asymmetric pore structure that is different than the first asymmetric pore structure, the second porosity comprising a second mean pore size, wherein the ratio of first mean pore size to the second mean pore size is at least about 5:1.