MATERIALE A PELLICOLA REVERSIBILMENTE TRASPARENTE-TRANSLUCIDO E PROCEDIMENTO PER LA SUA PRODUZIONE

摘要

Normally transparent films which can be rendered translucent by stretching and transparent by relaxing the film are provided. The films comprise a blend of crystallizable polymer with a compound with which the polymer is miscible at a temperature above the crystallization temperature of the crystallizable polymer-compound blend but immiscible at a temperature below the crystallization temperature of the blend. The films are prepared by blending the crystallizable polymer with the compound under melt conditions, casting a film of the blend and cooling to solidify the blend.