Dye sublimation ink is a water-based ink that works with a wide variety of inkjet printers. Most are adapted from standard eco-sol models, though a few have been purpose-built.
This ink is very widely used for textiles because it is easy to work with and only requires heat and a little pressure as a post-process.
It produces bright colours, but the limitation is that it only works with polyesters. Polyester-natural fibre mixes can be used, but the less polyester the fewer the binding points for the dye, so the image is duller and wash resistance suffers.
The ink can be used either to print onto sublimation transfer paper or directly to the textile. Some manufacturers call it ‘disperse dye,’ usually when referring to direct printing. In some cases, the same ink is used for paper as direct to the textile (which needs a pre-treatment to reduce spread and wicking into the fibres before it is heat-fixed).
Both method require heat activation for 45 to 60 seconds. With transfer methods, a roll of paper is initially printed with the ink, which is then dried. In a separately process (normally) the paper is pressed onto the target textile and heat is applied.
The ink vaporises (‘sublimates’) and crosses to the textile, where it is absorbed by the polyester fibres and blends with them permanently. The transfer can be done with a heat press for sheets, or with a calendaring roller for rolls of material.
With the direct method, the polyester textile is printed directly on the inkjet. The ink dries, but initially the colour doesn’t bind into the fibres so the image looks dull. The textile is then run through a calendaring roller, when the heat causes it to sublimate and bind to the fibres. The image then takes on its full brightness.