| 摘要 |
<p>PURPOSE: To prevent a crack from developing at the time of folding material to manufacture a container by extrusion molding a polymer containing a propylene having a specific melt index as a base and simultaneously forming a fold by plastical deformation. CONSTITUTION: A web contains a propylene containing 50 to 80% of a total weight of mineral substance as a base and which has a melt index of 0.5 to 5 according to ASTM (2.16 kg, 230 deg.C) and the base layer 4 is provided with a pattern of crease lines 5, 6 which have been formed by plastic deformation in connection with or immediately after the extrusion of the base layer. To manufacture the web 1, a particulate propylene base polymer and a mineral substance filler are charged in funnels 9, 10 of an extrusion molding machine 7, heated, and extruded via a nozzle 8 to form a film 1', which is passed through a nip of cooling compression cylinders 11, 12. The cylinder 11 has a pattern formed by a protrusion on an outer surface, is pressed by the pattern to form the lines 5, 6 on a surface of the film 1' to become the film 1 and wound on a magazine roll 13.</p> |
