| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat-shrinkable polyester film having high shrinkability, excellent not only in shrink finish but also in perforation properties and suppressed in shrink stress. SOLUTION: The heat-shrinkable polyester film comprises 70-90 wt.% of a copolyester resin (A), wherein a dicarboxylic acid component is terephthalic acid, a diol component is ethylene glycol and a copolymerizable component is 20-50 mol% of 1,4-dicyclohexanedimethanol, and 10-30 wt.% of a copolymerized polybutylene terephthalate resin (B) wherein a dicarboxylic acid component is terephthalic acid, a diol component is 1,4-butanediol and a copolymerizable component is 5-20 mol% of isophthalic acid. In this heat-shrinkable polyester film, the maximum shrink stress (85°C silicone bath immersion) in the main shrink direction of the film is 5.5 MPa or below and the shrinkage factor of the film after treatment in hot water at 80°C for 10 sec is 35-50% in the main shrink direction. COPYRIGHT: (C)2005,JPO&NCIPI |
