CO-EXTRUSION MULTI-LAYERED FILM

摘要

PURPOSE:To improve sealing strength, by molding a co-extrusion multi-layer film consisting of a straight chainlike ethylene-alpha-olefin copolymer layer, polypropylene resin and ethylene-alpha-olefin copolymer layer. CONSTITUTION:A co-extrusion multi-layer film which is formed of a layer A made up of straight chainlike ethylene-alpha-olefin copolymer whose density is 0.910-0.945g/cm<3> and a resin composite layer B made up 60-98wt% polypropylene resin and 40-2wt% ethylene-alpha-olefin copolymer whose density is less than 0.945g/cm<3> is formed by making a ratio of the layer A to a whole layer more than 50%. The foregoing multi-layered film is molded by a co-extrusion molding method and as for far concrete method an inflation method using a circular die and a T die co-extrusion molding method using a flat die are applied to this molding.