Method and apparatus for heating nonwoven webs
AssigneeE.I. du Pont de Nemours and Company
InventorsJohn C. Cleary, Michael C. Davis, Todd A. McCoy, Edgar N. Rudisill
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Abstract
A process for drying/heat-treating nonwoven webs in which the web is partially dried under tension in a first drying zone and further heat treated under low tension or in a substantially tensionless state a second drying zone. The process significantly reduces the occurrence of stretch-type defects in the nonwoven webs.
Claims6
A method for curing a chemical agent deposited on a multiple component nonwoven fabric, comprising heat treating a multiple component nonwoven fabric comprising a first polymeric component, a second polymeric component and a curable chemical agent, the first polymeric component having a melting point or softening point that is at least 10° C. lower than the melting point or softening point of the second polymeric component, by passing a length of said fabric through a tension isolation means to reduce the tension on said fabric in any one direction to between 0 and 52.5 N/m, and heating the nonwoven fabric to a sufficient temperature for a sufficient time to cure said chemical agent, wherein said temperature is greater than about (Tm−40)° C., where Tm is the melting or softening point of the first polymeric component, but less than (Tm−10)° C., while the nonwoven fabric is under such reduced tension.
Dependencies are inferred from the claim text.