Like thermal transfer printers, sublimation printers use an ink ribbon. The dye on the foil is heated to a specific temperature at which it evaporates and then diffuses into the substrate. For that diffusion process a specially coated substrate is necessary. Depending on the temperature applied, a varying amount of dye is diffused into the substrate. This facilitates the production of an image with continuous tone colours. Thermal dye sublimation is a possible integration technique for biodata / photo / signature integration.
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