PURPOSE: To form a clear recorded image of excellent quality on a recording medium at a low recording cost, by applying thermal perforation to a thermoplastic resin film while making the film and a dot-shaped heating element move slidably.

CONSTITUTION: A thermoplastic resin film 1 such as a drawn polypropylene film is drawn out of a roll 2a and transferred continuously or intermittently in the direction of an arrow A. When a heat suitable for a desired picture pattern is impressed from a heating element 4a onto the film 1 while the film 1 moves slidable on the heating element 4a, the film 1 is thermally perforated uniformly in accordance with the aforesaid pattern. Since the resin film 1 slides on the heating element 4a, the melt 1c of the resin which is the material constituting the film 1 is pushed from a perforation 1b onto the surface of the film, at one end of the periphery of the perforation in the direction reverse relatively to that of running of said film, and it is accumulated and cured thereat in a prescribed shape. Ink 6a passes through a perforated portion 1a formed uniformly in the film 1, sticks on a recording medium 5 and forms a clear recorded image 8 having an excellent printing quality.