Polymeric mats having continuous filaments with an asymmetrical cross-sectional shape

Abstract

Abstract A lofted mat of filaments is produced from process and apparatus including: supplying a plurality of streams of molten polymeric material; attenuating said streams of material into continuous filaments through the action of a stream of fluid moving from an attenuation means; said filaments being entrained in said fluid moving from said attenuation means, said filaments having non-uniform residual stresses established therein; moving said stream of fluid and filaments along a first surface positioned intermediate said attenuation means and a foraminous surface; establishing a vacuum at said foraminous surface; directing said stream of fluid and filaments into said foraminous surface obliquely oriented with respect to said first surface such that a first portion of said fluid separates from the filaments and passes through said foraminous surface and a second portion of said fluid moves said filaments along the foraminous surface; collecting said filaments in a randomly dispersed, substantially uniform layer having a first thickness; passing said layer through crimp inducing means adapted to permit said unbalanced, residual stresses to randomly crimp said filaments to form said lofted mat having a second thickness greater than said first thickness wherein said lofted mat is comprised of a lofted mat comprising a plurality of continuous polymeric filaments having an asymmetrical cross-sectional shape, the cross-sectional shape having a major dimension within the range from about 0.00150 inch to about 0.00350 inch, the filaments having a crimp factor within the range from about 0.1 to about 4 waves per inch of filament, said mat having a density within the range from about 0.33 pounds per cubic foot to about 1.74 pounds per cubic foot.

Inventors

• 👤 John L. Kane
• 👤 Vikas M. Nadkarni

Bibliographic Details