| 摘要 |
<p>Packaging materials having a polyolefine film on the surface which is to form the outside of the package and a surface of heat-sealable plastics material on the side which is to form the interior of the package are coated on the polyolefine surface, at least on that portion which during the packaging operation will contact a heated pressure tool, with a layer of paraffin hydrocarbon which is solid at normal room temperatures but has a melting point lower than the polyolefine film. Preferably, the paraffin is applied molten at a temperature near the melting point or range of the polyolefine, so that it "blends" with the polyolefine forming a "boundary region" in which both materials are present. The packaging materials may be wholly composed of polyolefine or may comprise paper, metal or other plastics.</p> |
