| 摘要 |
PROBLEM TO BE SOLVED: To improve the releasability with an adhesive resin and to suppress the protrusion of the resin by specifying the tensile elongation at break of a tetrafluoroethylene copolymer film. SOLUTION: A tetrafluoroethylene type copolymer film is used as a release film. A tetrafluoroethylene type copolymer is a copolymer of tetrafluoroethylene and other copolymer component. The content ratio of a polymer unit based on tetrafluoroethylene in the tetrafluoroethylene type copolymer is set according to the kind of the other copolymer component but may be usually set to 30-70mol%, pref., 40-60mol%. The tensile elongation at break of the tetrafluoroethylene type copolymer film at 200 deg.C is 100% or more, pref., 200% or more. By this constitution, the protrusion of a resin is suppressed and the release film can be easily peeled. |
