Ribbon Normalization by Preheating
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Jan-31
In resistive ribbon thermal transfer printing, the print quality and liftoff, or correction, are temperature and humidity dependent. This dependency is lessened by preheating the ribbon immediately prior to printing. Accordingly, Joule heating is achieved by having two relatively broad area electrodes in contact with the resistive side of the ribbon on the upstream side of the head, that is, between where the ribbon exits the cartridge and before where the ribbon is contacted by the print electrodes. Current is passed through these electrodes by an amount necessary to raise the temperature of the ribbon a certain amount above ambient. The temperature delta is chosen to desorb water and normalize the ribbon prior to printing.