Nanoweb structure

Abstract

A nanoweb of polymeric nanofibers in which all of the polymeric fibers have a mean curl index when measured over any 100 micron long segment of less than 0.10 and the nanoweb has a uniformity index of less than 5.0. The nanoweb may have a fiber orientation index of between 0.8 and 1.2 or a mean flow pore size minus the mode of the pore size is less than 1.0 and simultaneously the ratio of the 99% width of the pore size distribution (W) to the width at half height of the pore size distribution (HM0) is less than 10.0. The invention is further directed to a nanoweb with a multiplicity of continuous polymeric fibers arranged in clusters wherein fibers have an average diameter less than 1,000 nm and wherein the web has a gross morphology corresponding to the following structure; each fiber is laid in an arc of essentially constant curvature along its length; all of the fiber arcs in a given cluster have essentially the same curvature; the fiber arcs in a given cluster are co-planar and any given fiber arc in a given cluster lies spaced away from and essentially parallel to the other arcs in said cluster in the plane of the cluster; and the centers of curvature of the fiber arcs in a given cluster are co-linear.

Dependencies are inferred from the claim text.