Patent ID: 6051177
Filing Date: 2000-04-18
Classification: B29C,D06C,Y10S,Y10T

Abstract:
A process for manufacturing a nonwoven web comprising a blend of thermoplastic and non-thermoplastic fibers having elastic properties in a cross machine direction consisting essentially of:(a) unwinding a thermally bonded nonwoven web into a first variable tension means which feeds said web into a web heating means at a temperature no more than 70.degree. F. Above the plastic point of said precursor web, and(b) continuously stretching the heated web lengthwise in the machine direction within said web heating means by a second variable tension means sufficient to provide a cumulative strain rate of at least 3.5 inches/inch/minute but less than 9.5 inches/inch/minute, said strain rate calculated based on the gauge length between individual elements of said tension means, whereby said web is narrowed in the crossmachine direction and lengthened in the machine direction, which is its longitudinal or lengthwise dimension, and wherein said web develops an elasticity of at least 80% recovery after being elongated at least 50% in the direction perpendicular to and in the same plane as said tension means, and is characterized by improved softness compared to the precursor web, improved conformability compared to said precursor web, an increase in basis weight of at least 5% compared to said precursor web, and a decrease of maximum pore size of no more than 20% compared to said precursor web, and(c) cooling the web and collecting the cooled web on a winder.