Sublimation is when a substance goes through the transition between the solid and gas states without going through a liquid stage. Dry ice is an example. In a dye sublimation printer the printing dye is heated up until it turns into a gas, at which point it diffuses onto the printing media and solidifies. Dye sublimation can also be used as an indirect printing process. Standard black and white laser printers are capable of printing on plain paper using a special transfer toner containing sublimation dyes which can then be permanently heat transfered to hats, mugs, metals, puzzles, and other surfaces.
Dye sublimation printing can be used to print on fabrics and clothing, for example T shirts, and ceramic products such as mugs. The ink is applied to a donor material, a special type of paper. The image on the paper is a reverse image of the final design, so that when it is dry it can be placed onto the fabric or ceramic and heated, transferring the completed image onto the material via the dye sublimation process. In any case, the dye turns into gas and permeates the actual fibres of the material, then solidifies. Sublimation printing does not produce that bump feeling when you run your fingers over the printed area. Its as if the image was part of the product all along.
What materials can be printed & what limitations are there?
Just about anything that has a sublimate coating on it can be printed on. Limitations include natural fibers such as cotton, printing on 100% cotton will cause the image to fade and wash out. Sublimation inks are dark, yet print out with bright and vibrant colours. You cannot print on dark coloured materials; you can however print on pastel colours and white.