Dye-sublimation
A printing process in which solid dye is heated into a gas that diffuses into a receiving surface and solidifies there.
In depth
Because the dye diffuses rather than being deposited as droplets, tonal transitions are genuinely continuous with no dot structure at all. The process suits small photographic prints, ID cards and printing onto fabrics and coated aluminium, and it is normally finished with a protective clear overcoat.
Examples in practice
An event photo booth prints a fully dry, laminated 6×4 in about twelve seconds by dye-sublimation.