GAS BARRIER BIAXIALLY ORIENTED POLYPROPYLENE FILM WITH EXCELLENT TRANSPARENCY, LAMINATED FILM, AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To provide a gas barrier biaxially oriented polypropylene film with excellent gas barrier performance after elongation and transparency by providing excellent transparency and steam and oxygen barrier properties. SOLUTION: The gas barrier biaxially oriented polypropylene film comprises a base layer containing polypropylene polymer as a main component, a polyolefin resin layer provided at least on one surface of the base layer and having a melting heat quantity of 30 to 85 J/g, and an incompletely oxide alumina film provided on the resin layer. In this case, in the alumina film, its aluminum metal concentration is more than any of an interface between the surface and the resin layer and aluminum metal content in the alumina film are 10 to 200% nm. Steam and oxygen barriers are excellent, further gas barrier after elongation is excellent and transparency is excellent.