Patent ID: 9186608
Filing Date: 2015-11-17
Classification: B01D,B29C

Abstract:
1. A process for forming a high efficiency filter comprising: forming a non-woven layer having pores from a plurality of thermoplastic fibers having a median diameter of less than about 2 micrometers, wherein the formed non-woven layer contains no electrostatic charge; saturating the non-woven layer in a wetting liquid, wherein the wetting liquid has a surface tension of less than the surface tension of the thermoplastic making up the thermoplastic nanofibers, wherein the wetting liquid completely wets the pores in the non-woven layer; drying the wetted non-woven layer forming a dried non-woven layer at room temperature such that size and shape of at least a portion of the pores change, wherein the dried non-woven layer has higher filtration efficiency than the formed non-woven layer, and wherein the dried non-woven layer contains no electrostatic charge.