HEAT SHRINKABLE POLYESTER FILM AND PREPARATION METHOD THEREOF

摘要

PURPOSE: A heat-shrinkable polyester film is provided to prevent the film from unevenly shrunk and to obtain excellent transparency, adhesive force with a solvent, mechanical strength to the longitudinal direction of the film, and crack resistance. CONSTITUTION: A heat-shrinkable polyester film includes ethylene terephthalate as a main repeating unit. The polyester film is stretched in the longitudinal direction of the film. The phase difference in a plane is 4000-4400 nm. The percentage of contraction of the film is less than 20% when the film is maintained at warm water of 70 °C for 10 seconds and the percentage of contraction is more than 40% when the film is maintained at warm water of 90 °C for 10 seconds.