Process for making a stretchable nonwoven web
AssigneeE. I. Du Pont de Nemours and Company
InventorsJames Edmond Van Trump, Vishal Bansal, Michael C. Davis
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Abstract
A process for preparing nonwoven webs including multiple component continuous filaments having high levels of three-dimensional helical crimp utilizing draw rolls to provide a high degree of orientation to each of the polymeric components by mechanically drawing the filaments under conditions wherein the polymeric components remain substantially amorphous and a stretchable nonwoven web including multiple component, continuous filaments having high levels of three-dimensional helical crimp.
Claims10
A method for forming a stretchable nonwoven web comprising the steps of:
- melt spinning a plurality of continuous filaments comprising at least first and second distinct melt-spinnable polymers, the polymers being arranged in distinct substantially constantly positioned zones across the cross-section of the filaments in an eccentric relationship and extending substantially continuously along the length of the filaments;
- quenching the filaments in a quench zone using a gas;
- passing the filaments in a single wrap alternately under and over at least two serpentine feed rolls, the feed rolls being rotated at a surface speed such that the first and second polymers remain substantially amorphous in the quench zone,
- passing the filaments in a single wrap alternately under and over at least two serpentine draw rolls, the draw rolls being rotated at a surface speed that is greater than the surface speed of the feed rolls so that the filaments are drawn between the feed rolls and the draw rolls, the temperature of the draw rolls being sufficient to form partly-crystalline filaments of the first and second polymeric components,
- passing the partly-crystalline filaments into a gas forwarding jet, the jet imparting tension to the filaments between the draw rolls and the jet,
- passing the drawn and partly-crystalline filaments out of the gas forwarding jet thereby releasing the tension on the filaments and causing the filaments to form helical crimp,
- depositing the filaments onto a moving support surface located below the forwarding jet to form a nonwoven web of helically crimped filaments.
Dependencies are inferred from the claim text.