Processing aid and blend employing the processing aid for achieving effective orientation of an extruded film layer and a biaxially oriented film including such film layer

Abstract

Processing aid for aiding in orienting an extruded film layer including a preponderance, by weight, of a high crystalline polypropylene is a crystalline polypropylene wax. An oriented film layer including a blend of crystalline polypropylene wax and high crystallinity polypropylene homopolymer is part of the invention. The invention includes a method of forming an oriented film layer including a preponderance by weight of a high crystallinity polypropylene and includes the steps of blending a high crystallinity polypropylene with a crystalline polypropylene wax, directing the blend through an extruder to form a film layer and then orienting the film layer. The invention includes a biaxially oriented, multi-layer film including a base layer and at least one skin layer. The base layer includes a blend of crystalline metallocene catalyzed polypropylene wax and a high crystallinity polypropylene.

Dependencies are inferred from the claim text.