US Patent 7905973 Molded monocomponent monolayer respirator

A molded respirator is made from a monocomponent monolayer nonwoven web of continuous charged monocomponent meltspun partially crystalline and partially amorphous oriented fibers of the same polymeric composition that have been bonded to form a coherent and handleable web which further may be softened while retaining orientation and fiber structure. The respirator is a cup-shaped porous monocomponent monolayer matrix whose matrix fibers are bonded to one another at least some points of fiber intersection. The matrix has a King Stiffness greater than 1 N. The respirator may be formed without requiring stiffening layers, bicomponent fibers, or other reinforcement in the filter media layer.