Thermal Transfer Printers often called thermal wax printers. employs ribbon of wax coated material (hot melt ink) on a roll. The ribbon is transported past the print head which is heated by semiconducter resistors to melt the ink and transfer it to the paper. Can be thought of as digital version or iron-on. Generally are binary printers but some variable dot-size versions exist. Requires special smooth paper. How stick printers from Tektronix combine thermal transfer and ink jet technology. Dye sublimation Also called dye diffusion printers. Similar to thermal transfer printers except that they use transparent dyes instead of hot melt inks. This allows production of a nearly continuous tone or photographie quality output. When dye sub ribbon is contacted by printhead the dye sublimes (vaporizes) and then diffuses into a special coated substrate. The 3M Rainbow proofer in our laboratory is a dye sublimation device. (The Fargo printer does both thermal wax and dye sublimation.)