Patent ID: 8637134

Claim:
A method of producing vented plastic stretch film, said method including the steps of: providing an elongated base sheet of plastic stretch film having a longitudinal axis; transporting the elongated base sheet in a direction of movement corresponding to the longitudinal axis of said elongated base sheet; simultaneously with the transport of said elongated base sheet, forming a plurality of cord-like, elongated reinforcement members, where each of said cord-like, elongated reinforcement members is made by simultaneously randomly compressing a transported flat, narrow plastic film strip by randomly compressing said flat, narrow plastic film strip by rotating a collector roll and employing a compressor nozzle during transport thereof; during transport of said elongated base sheet, attaching said plurality of cord-like, elongated reinforcement members to said elongated base sheet, said cord-like, elongated reinforcement members extending along the longitudinal axis of said elongated base sheet, spaced from one another and disposed substantially parallel to one another; transporting said elongated base sheet and said cord-like, elongated reinforcement members attached thereto in the direction of movement to the longitudinal axis of said elongated base sheet; during transport of said elongated base sheet and said cord-like, elongated reinforcement members attached thereto, positioning a narrow plastic film strip overlay over each of said cord-like, elongated reinforcement members, said narrow plastic film strip overlays being parallel and spaced from one another; attaching said narrow plastic film strip overlays to said cord-like, elongated reinforcement members and to said elongated base sheet to fixedly sandwich said cord-like, elongated reinforcement members between said elongated base sheet and said narrow plastic film strip overlays, said narrow plastic film strip overlays and said cord-like, elongated reinforcement members comprising parallel, elongated reinforcement strips defining elongated spaces therebetween, said base sheet being uncovered in said elongated spaces; and during transport of said elongated base sheet and said elongated reinforcement strips, forming a plurality of slits in said elongated base sheet in the elongated spaces defined by said elongated reinforcement strips and applying tensional forces to said base sheet to stretch said elongated base sheet and expand and open said slits to form vent holes therefrom, said elongated reinforcement strips operable to restrict formation of said vent holes to the spaces defined thereby.