Polypropylene film with cold seal release and cold seal receptive surfaces

摘要

An oriented polymeric alpha-olefin film having: an isotactic polypropylene homopolymer core; a cold seal release skin layer adherent to one side of the core; and a surface treated cold seal receptive layer or such treated layer with a cold seal cohesive composition over the surface treatment of said layer on the other side of the core. The cold seal release skin layer comprises a slip agent and a blend of two polymers, namely, an ethylene-propylene random copolymer containing about 2% to 8% of ethylene in such copolymer and an ethylene-butylene copolymer containing about 0.5% to 6% of ethylene in such copolymer. The cold seal receptive layer is of an ethylene-propylene random copolymer containing about 2 to 8% of ethylene.