Patent ID: 7390575
Filing Date: 2008-06-24
Classification: B32B,C08F,C08L,Y10S,Y10T

Abstract:
1. A polyolefin based biaxially oriented multi-layer film having at least one surface layer comprising a propylene-ethylene random block copolymer; the propylene-ethylene random block copolymer obtained through sequential polymerization catalyzed by a metallocene component comprising 30 to 70 wt % of a propylene-ethylene random copolymer component (A) having an ethylene content of 1 to 7 wt % produced in the first step of the polymerization and 70 to 30 wt % of a low crystalline or an amorphous propylene-ethylene random copolymer component (B) produced in the second step of the polymerization having an ethylene content of 6 to 13 wt % higher than that of the polymer component obtained in the first step, wherein the propylene-ethylene random block copolymer shows a single peak at 0° C. or lower in the temperature-loss tangent (tan δ) curve obtained by dynamic mechanical analysis (DMA).