Patent ID: 6953617

Claim:
A biaxially oriented, transparent, multilayer packaging film, said film including a core layer and opposed, functional skin layers, said core layer including a blend comprising: a) a high modulus polypropylene having an isotactic index of at least about 92% and being present in a range greater than 40% to less 90% by weight of the blend and b) a 1-butene/ethylene copolymer in a range greater than 10% to less than 60% by weight of the blend, wherein the 1-butene/ethylene copolymer comprises about 0.5% to about 10 wt % of an ethylene; said core layer being biaxially oriented at a temperature resulting in said core layer having an oxygen transmission rate of at least about 200 cc/100 sq. in./day/atmosphere (3077 cc/sq. m./24 hr./atmosphere), a tensile modulus in at least one direction of at least about 160,000 psi (1.103 GPa) and a haze value of no greater than about 3% and wherein the oxygen transmission rate, the tensile modulus and the haze value are measured at a thickness of about 1 mil (25 μm); and c) said functional skin layers being substantially thinner than said core layer.