Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state. In the world of signs, this means you have to have a poly-coated substrate that accepts sublimation ink. We print on sublimation paper with a printer (much like a regular printer) that has sublimation ink, in reverse. This is then taped to the substrate and pressed with a heat or mug press. At this point, the ink on the paper is then transferred to the substrate, and presto!