HEAT-SHRINKABLE POLYESTER FILM AND PROCESS FOR PRODUCING THE SAME

摘要

Provided is a heat-shrinkable polyester film whose main shrinkage direction is the machine direction. This film does not shrink in the machine direction in a low-temperature region and, despite this, highly shrinks in a high-temperature region. The film has an extremely high mechanical strength in the transverse direction, which is perpendicular to the main shrinkage direction. The film is suitable for use especially as a film for forming covering labels for dry cells and in applications similar thereto. The heat-shrinkable polyester film shrinks mainly in the machine direction. The film has been regulated so that the degree of machine-direction hot-water thermal shrinkage through 10-second immersion in 80°C water is in a given range and the degree of machine-direction thermal shrinkage and degree of transverse-direction thermal shrinkage through 10-second immersion in a 140°C glycerol bath are in respective given ranges.