PURPOSE: To thermal-bond films and render the finish more beautiful during cutting then.

CONSTITUTION: There is provided a vertically movable upper heater 10 having press surfaces PF, PF, a cushion materials 21, 21 opposite to the press surfaces PF, PF, and a heater wire 31 stretched between the cushion materials 21, 21, and on the heater 10, press plates 19, 19 are provided. By the upper heater 10, when films F, F are held between the press plates 19, 19 and the cushion material 21, 21, the films can be thermal-bonded by the press surfaces PF, PF, and thereafter the heater wire is raised to thereby fuse the films F, F.