摘要 |
PROBLEM TO BE SOLVED: To provide a heat-shrinkable polyester film, which gives iridescent metallic glossiness, is joined using a solvent as a film covering a container such as a PET bottle, and has excellent heat shrinkability. SOLUTION: In the polyester film, first layers each containing a polyester (A) containing ethylene terephthalate as an indispensable component and second layers each containing a polyester (B) containing ethylene-2,6-naphthalenedicarboxylate as a main component, are laminated alternately to form 25-1,001 layers. The percentage of the total thickness of the first layers to the thickness of the entire film is 80-90%. The polyester (A) contains 20-60 mol% of a second acid component to the total acid components of the polyester (A). The film has at least one reflection peak with a reflectance of 25% or more in a reflectance curve of 400-800 nm wavelength. The thermal shrinkage factor in the longitudinal or width direction of the film when the film is immersed in warm water of 80°C for 10 s is 30% or more and≥0% and <10% in an absolute value in the direction crossing this direction rectangularly. COPYRIGHT: (C)2010,JPO&INPIT |