Characterization of a resistive ribbon thermal transfer printing process
by T. G. Twardeck
Resistive ribbon thermal transfer printers transfer ink from a ribbon to paper as the result of localized Joule heating of the ribbon structure. For this printing process, this paper discusses the voltage-versus-current response of the electrode-ribbon current path, the temperature distributions throughout the ribbon structure, and the correlation of print response with electrical input power and average ribbon temperatures. Nominal input power per electrode is approximately 190 mW. For input power near this level, thermal models predict that ribbon materials which pass directly under energized electrodes reach the highest temperatures; the hottest zone in the ribbon surrounds the composite-aluminum interface. Approximately 0.1 mm downstream from the electrodes, the heated ribbon materials come to nearly constant temperature. The area of the printed image correlates with this average ribbon temperature and input power.