| 摘要 |
Plastic films or sheets having tear lines formed therein are disclosed. These films are made by forming a score along a predetermined line in the surface of a plastic film to form a tear line and then restoring the scored film surface without eliminating the line of tear. The products tear very easily along predetermined lines even though the restored plastic films have enhanced impact strengths. By restoring the surface of the scored film, score lines become invisible to the naked eye and the useful life of the film is extended. Single-ply or multi-ply products are disclosed including products having an embossed or textutred surface, still without eliminating the capability for a smooth line of tear. The products have many utilities as structural materials which may be sized or torn by hand, including wall coverings, window shade coverings, rupturable packages and envelopes, to mention a few. |
