a flexible wrapping material comprising a film laminate is provided for packaging of food products which is resistant to flex - cracking and pinhole development , is impervious to liquids and gasses , and exhibits the property of grease - resistance without the use of adhesives to promote bonds between the layers . the film laminate consists of an outer layer of heat - set , biaxially oriented polymeric material followed by a layer of polymeric material , a layer of oxygen barrier polymer , a layer of biaxially oriented polypropylene , a special grease - resistant polymer , and an inner layer of heat - sealable polymeric material . the film laminate is made by bonding the outer surface layer of heat - set , biaxially oriented polymer to a substrate in which an oxygen barrier material is carried on a biaxially oriented polypropylene / special grease - resistant polymer by means of an intermediate layer of polymeric material . a layer of heat - sealable polymeric material is then extrusion - coated on the special polymer surface to form the inner layer of the laminate .