BONDABLE, ORIENTED, NONWOVEN FIBROUS WEBS AND METHODS FOR MAKING THEM

摘要

Nonwoven fibrous webs comprise fibers of uniform diameter that vary in morphology along their length. The variation provides longitudinal segments that exhibit distinctive softening characteristics during a bonding operatio n. Some segments soften under the conditions of the bonding operation and bond to other fibers of the web, and other segments are passive during the bonding operation. Webs as described can be formed by a method that comprises a) extruding filaments of fiber-forming material; b) directing the filaments through a processing chamber in which the filaments are subjected to longitudinal stress; c) subjecting the filaments to turbulent flow condition s after they exit the processing chamber; and d) collecting the processed filaments; the temperature of the filaments being controlled so that at leas t some of the filaments solidify while in the turbulent field.