Patent ID: 6242084
Filing Date: 2001-06-05
Classification: B32B,Y10S,Y10T

Abstract:
An oriented multi-layer film which comprises:(a) (i) a voided layer comprising a metallocene-catalyzed substantially isotactic polypropylene polymer in a matrix with a cavitation initiator; (ii) at least one non-voided layer comprising a Ziegler-Natta catalyzed isotactic polypropylene polymer on at least one side of the voided layer; or(b) (i) a voided layer comprising a Ziegler-Natta catalyzed isotactic polypropylene polymer in a matrix with a cavitation initiator; (ii) at least one non-voided layer on at least one side of the voided layer comprising a metallocene-catalyzed polypropylene; or(c) (i) a voided layer comprising a metallocene-catalyzed substantially isotactic propylene polymer in a matrix with a cavitation initiator; (ii) at least one non-voided layer on at least one side of the voided layer comprising a metallocene-catalyzed polypropylene,wherein the WVTR value of the oriented multi-layer film is from about 0.5 to about 0.7 g-mil/100 in.sup.2 -day and the TO.sub.2 value of the film is from about 160 to about 200 cc mil/100 in.sup.2 -day.