procedure for the continuous pragen films

摘要

1484081 Embossing HOECHST AG 3 Sept 1974 [5 Sept 1973] 38448/74 Heading B6J A web of thermoplastic film is embossed while being tensioned in the longitudinal and transverse directions. Longitudinal tension is produced due to the web transport and the transverse tension may be produced by revolving clip chains holding the edges of the web. The transverse tension may be increased by using a diverging tenter. The web may be heated or cooled whilst still subject to tension. The embossing may be applied as a line or lines parallel to the longitudinal edges of the web and may be applied while the web is ductile. The lines may be closely spaced to permit slitting of the web therebetween. The embossing may be applied before, during or after a longitudinal or transverse stretching of the web.