Method for generating a watermark on a photo picture using a thermal printer

摘要

A method for generating a watermark on a photo picture using a thermal printer. The thermal printer includes a thermal printhead for heating an ink ribbon and sublimating color dyes stored in the ink ribbon on a photo picture. The ink ribbon includes a plurality of sequentially arranged color frames. Each color frame includes a plurality of dye frames with different color dyes and a dye frame with overcoating. The method includes using the thermal printhead to heat a color frame with a plurality of different color dyes and to sublimate the color dyes on a photo picture and using the thermal printhead to heat the dye frame with the overcoating and to heat different areas on the color frame by two distinct time periods.