Process for creating a variable density, high loft, non-woven web structure

摘要

A process is disclosed for creating air laid, high loft, non-woven, variable density web structures. The fiber manipulation and distribution necessary to produce a variable weight and density web is accomplished by creating variable, negative pressure regions across the surface of a condenser or other vacuum screen, which causes fibers to migrate toward areas of lower pressure. Also disclosed are embodiments of condenser and vacuum screens for producing such variable density web structures.

主权项

1. A process for creating a variable density, high loft, non-woven web structure, the process comprising the steps of:
(a.) establishing a non-uniform vacuum across the surface of a condenser screen in parallel banded regions to produce at least a first area having greater airflow than a second area; and (b.) condensing fiber onto said condenser screen in a non-uniform variable density arrangement across the surface of said condenser screen; wherein fiber is directed more heavily to the first area of the condenser screen having greater airflow, and fiber is directed less heavily to the second area of the condenser screen having lesser airflow; thereby, resulting in a high loft, non-woven web structure having density variations corresponding to the areas along the surface of said condenser screen having greater and lesser airflow.