Heat-shrinkable polyester films and labels

摘要

An object of the present invention is to provide a heat-shrinkable polyester film suitable for use as a label for shrink-wrapping of bottles, having an appearance of Washi paper, and almost free problems such as crinkling, shrinkage shading, and deformation due to heat shrinkage. The heat-shrinkable polyester film of the present invention is characterized by having variations in film thickness of 3 mu m or more per cm both in the maximum shrinkage direction and in the direction orthogonal to the maximum shrinkage direction, and by comprising a layer having voids with an average void diameter of 15 mu m or more in vicinity of a center part in film thickness direction and at least one surface layer having voids with an average void diameter of less than 5 mu m.