| 摘要 |
PROBLEM TO BE SOLVED: To provide a slackening heat treatment method which enables the efficient obtaining of a biaxially oriented thermoplastic resin film improved in flatness and excellent in thermal dimensional stability. SOLUTION: In this method for heat-treating a biaxially oriented polyester film, a long biaxially oriented polyester film is guided into a heating zone by a pair of sending-out rolls to be heated while being suspended in the heating zone to be allowed to run downward and the biaxially oriented polyester film is reversed in its running direction under the outside area of the heating zone to be guided to a cooling zone and cooled while being allowed to run upward by a pair of the take-off rolls arranged outside the area above the cooling zone. COPYRIGHT: (C)2011,JPO&INPIT |
