PURPOSE: To prevent the damage of the image printed on a pervious body, by applying the reversal printing of a desired image such as a character or drawing to one surface of the sheet-like pervious body such as a transparent or translucent film.

CONSTITUTION: In a thermal head 6, a plurality of heat generating resistors are provided to the printing surface being the surface opposed to a platen 3 in a line form and started by the transmission of a pulse signal to thermally transfer the ink of an ink film 4A to a transparent film 5A. Radiation fins 6a for radiating the heat accumulated by heat generating printing are mounted to the back surface of the thermal head 6. The pulse signal starting the heat generating resistors of the thermal head 6 is emitted so that the desired image such as a character or drawing to be printed becomes a reversed state with respect to one surface to be printed of the transparent film 5A. By this method, since the transparent film 5A is used so as to turn the surface on the side not printed with an image 10 of the film 5A upwardly, even when the surface of the film 5A is touched with a hand, the printed image 10 is not damaged.