| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cap seal in which a barrel member and a top plate are formed of the same kind of material, and heat-bonded at a low temperature, the barrel member is thin-walled, and the load on the environment is small. <P>SOLUTION: The cap seal comprises a barrel member formed of a cylindrical heat-shrinkable film and a top plate formed of a disk-like sheet joined with an upper part of the barrel member, and both the heat-shrinkable film to constitute the barrel member and the sheet to constitute the top plate are formed of polylactic acid polymer. The heat shrinkage factor of the heat-shrinkable film to constitute the barrel member (the value when the film is immersed in hot water of 90°C for 10 seconds) is, for example, ≥ 50% in the main drawing direction. The thermal deformation temperature of the sheet to constitute the top plate is, for example, ≥ 50°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
