The invention is a process and apparatus for producing a cross-linked, tubular film or “tape” that uses a motor driven nip roll assembly and a product driven idler roll to pump gases contained within the film in a desired direction. The process eliminates the need to create slits to vent gases that...http://www.google.fr/patents/US7500841?utm_source=gb-gplus-shareBrevet US7500841 - Apparatus for pumping gases in a film
