Patent ID: 6066369
Filing Date: 2000-05-23
Classification: B32B,D04H

Abstract:
A method of producing a composite web, comprising the steps of:(a) continuously producing a mat of thermoplastic synthetic resin filaments or fibers and feeding said mat around a bonding roller having a length at least equal to a width of said mat and a peripheral speed corresponding to a travel speed of the mat, said mat having opposite sides;(b) feeding generally tangentially onto one of said sides of said mat on said bonding roller from a wide-slit nozzle opening onto said mat where said mat runs onto said roller a melt of a thermoplastic synthetic resin in a plastic state to coat said one of said sides of said mat with a foil formed upon cooling of said melt to form a coated web;(c) electrostatically charging said melt as it is applied to said mat with at least one corona discharge electrode extending across the coated web and juxtaposed therewith;(d) after said coated web leaves said roller and while said mat and said melt are at a temperature at least in part resulting from heat at which said melt is bonded to said mat, biaxially stretching said coated web in a direction parallel to the length of the coated web and in a direction parallel to the width of the coated web to produce a biaxially stretched web; and(e) then cooling said biaxially stretched web to substantially room temperature.