| 摘要 |
<p>1,222,622. Composite film. KALLE A.G. 21 March, 1969 [22 March, 1968], No. 14969/ 69. Heading B2E. A composite film is made by applying e.g. by melt extrusion onto at least one surface of a mono axially oriented isotactic polypropylene base film a) an isotactic polypropylene, b) a mixture of isotactic polypropylene and up to 15% wt non isotactic polypropylene, or c) a polymer mixture or a copolymer of propylene and up to 15% wt ethylene, and stretching the coated film in the orthogonal direction to biaxially orient the base film, and monoaxially orient the coating layer. The base film may be subjected to electrical discharge prior to coating and/or after orthogonal stretching. The composite film may have a polyethylene layer extruded thereon prior to stretching or may be coated with a heat sealable material e.g. polyvinylidene chloride copolymer, or a metal e.g. Al, Au, Ag, Cu.</p> |
