Methods of forming fibrous filtration face masks

摘要

A method of forming a cup-shaped, non-woven fibrous shaping layer for a filtering face mask. The method includes the steps: (a) heating a non-woven fibrous web that contains at least 40 weight percent thermally bonding fibers, where at least 10 weight percent of the fibrous material is bicomponent fibers, to a temperature at which the thermally bonding fibers, including at least one component of the bicomponent fibers, are softened; and then (b) molding the heated non-woven fibrous web, while the thermally bonding fibers and the at least cone component of the bicomponent fibers are still soft, in a mold having molding members that are at a temperature below the softening temperatures of the thermally bonding fibers, including all components of the bicomponent fibers.