Spot blocked thermoplastic film laminate

Abstract

There is provided a laminate of at lest two thermoplastic films which has a plurality of embossed parallel ribs running in at least one direction, said films being blocked together at spaced apart spots along each rib. Such laminate is prepared by passing at least two thermoplastic films in a superimposed and contacting engagement with one another through the nip of a pair of rollers. One roller is provided with a plurality of parallel raised ribs running in one direction and the other roller is provided with a plurality of parallel raised ribs which run in a direction angled to the direction of the ribs on the first roller. At the locations where the ribs on each roller cross at the nip, the films in the laminate are blocked together but otherwise remain unattached. Such laminates have exceptionally high tear strength and added stiffness and are adapted for various uses, including heavy duty bags and grocery sacks.

Dependencies are inferred from the claim text.