T-shirt printing by sublimation has grown into a substantial industry over the last 25 years and has filled a market gap for high-quality, short-run printing of shirts and other promotional items. It is a heat transfer process, whereby a paper release liner is printed using sublimation dyes. The printed image turns into a gas with the application of heat, transferring the dye to the garment or item.
Sublimation transfers were printed on commercial offset printing presses during the 1960s and 1970s, until the advent of the personal computer and inkjet printer in the 1980s. Development of sublimation dyes for inkjet use quickly followed suit.
Changing from printing presses to inkjet meant that as few as one sublimation transfer could be produced cost effectively; rather than the long runs and high set-up costs associated with commercial printers. Multi-color transfers could also be produced as easily as single color, which required four separate plate and printing operations using traditional methods.
Sublimation dyes present brighter colors when applied to polyester fabrics, but their transparent nature makes them ineffective on darker colored garments. Since the application of transfers is largely done by hand, and the cost of transfer material and dyes is high, production of larger volume orders is expensive.
T-shirts printed by sublimation have a noticeably softer feel to the printed area. Since imprints are dye-based, rather than ink-based, the dye actually becomes part of the fabric color, embedded within the fibers.
Printing by dye sublimation has grown substantially since the 1980s. Improvements in dye color opacity, ease of transfer combined with the type, quality and quantity of products that can be printed by the process ensures sublimation will remain a viable specialty process with a bright future.