The Dye Sublimation Process
A dye-sublimation printer (or dye-sub printer) is a computer printer which employs a printing process that uses heat to transfer dye onto a medium such as a plastic card, paper, or polyester fabric. The sublimation name is applied because the dye transitions between the solid and gas states without going through a liquid stage. Many consumer and professional dye-sublimation printers are originally designed for producing photographic prints.
(source: Wikipedia)
Sublimation is the transition of a substance from the solid phase to the gas phase without passing through an intermediate liquid phase. Sublimation is an endothermic phase transition that occurs at temperatures and pressures below a substance's triple point in its phase diagram.
At normal pressures, most chemical compounds and elements possess three different states at different temperatures. In these cases the transition from the solid to the gaseous state requires an intermediate liquid state. Note, however, that the pressure referred to here is the partial pressure of the substance, not the total (e.g. atmospheric) pressure of the entire system. So, all solids which possess an appreciable vapor pressure at a certain temperature usually can sublimate in air (e.g. ice just below 0°C). For some substances, such as carbon and arsenic, sublimation is much easier than evaporation from the melt, because the pressure of their triple point is very high, and it is difficult to obtain them as liquids.
Sublimation requires additional energy and is an endothermic change. The enthalpy of sublimation (also called heat of sublimation) can be calculated as the enthalpy of fusion plus the enthalpy of vaporization. The reverse process of sublimation is deposition. The formation of frost is an example of meteorological deposition.
(source: Wikipedia)