A Sublimation printer is a computer printer which uses heat to transfer dye onto materials such as a plastic, card, paper, or fabric. The sublimation name was first applied because the dye was considered to make the transition between the solid and gas states without going through a liquid stage. This understanding of the process was later shown to be incorrect. There is some liquefying of the dye. Since then, the process is sometimes known as diffusion, though this has not eliminated the original name.Many consumer and professional dye-sublimation printers are designed and used for producing photographic prints, ID cards, clothing, and so on and more.
Dye-sublimation printing is a digital printing technology using full color artwork that works with polyester and polymer-coated substrates. Also referred to as digital sublimation, the process is commonly used for decorating apparel, signs and banners, as well as novelty items such as cell phone covers, plaques, coffee mugs, and other items with sublimation-friendly surfaces. The process uses the science of sublimation, in which heat and pressure are applied to a solid, turning it into a gas through an endothermic reaction without passing through the liquid phase.
In sublimation printing, unique sublimation dyes are transferred to sheets of “transfer” paper via liquid gel ink through a piezoelectric print head. The ink is deposited on these high-release inkjet papers, which are used for the next step of the sublimation printing process. After the digital design is printed onto sublimation transfer sheets, it is placed on a heat press along with the substrate to be sublimated.
The most common process lays one color at a time, the dye being stored on a polyester ribbon that has each color on a separate panel. Each colored panel is the size of the medium that is being printed on; for example, a 6″ by 4″ dye sub printer would have four 6″ by 4″ panels.
During the printing cycle, the printer rollers will move the medium and one of the colored panels together under a thermal printing head, which is usually the same width as the shorter dimension of the print medium. Tiny heating elements on the head change temperature rapidly, laying different amounts of dye depending on the amount of heat applied. Some of the dye diffuses into the printing medium.
Traditionally, the advantage of dye-sublimation printing has been the fact that it is a continuous-tone technology, where each dot can be any color. In contrast, inkjet printers can vary the location and size of ink droplets, a process called dithering, but each drop of ink is limited to the colors of the inks installed. Consequently, a dye-sublimation printer produces true continuous tones appearing much like a chemical photograph. An inkjet print is composed of droplets of ink layered and scattered to simulate continuous tones, but under magnification the individual droplets can be seen. In the early days of inkjet printing, the large droplets and low resolution made inkjet prints significantly inferior to dye-sublimation, but some of today’s inkjets produce extremely high quality prints using microscopic droplets and supplementary ink colors, producing superior color fidelity to dye-sublimation.
The dye-sublimation printing process is used to print on polyester or other synthetic fabrics. It is used for applications such as T-shirts, banners, table covers, id cards, sportswear and flags. The original printers were an electrostatic technology using toners but now are generally large format inkjet printers using specially formulated inks. The dye sublimation inks are a disperse dye suspended in a liquid solvent, like water. The images are initially printed on coated heat-resistant transfer paper as a reverse image of the final design, which is then transferred onto polyester fabric in a heat press operating at a temperature around 180 to 210 C (375 F). Under high temperature and pressure, the dye turns into a gas and permeates the fabric and then solidifies into its fibers. The fabric is permanently dyed so it can be washed without damaging the quality of the image. Shelfies and Blue Notes are two such companies that use this method.
Advantages of dye-sublimation over other methods of textile printing:
Images are permanent and do not peel or fade.
Dye does not build up on the fabric.
Colors can be extraordinarily brilliant due to the bonding of the dye to the transparent fibers of the synthetic fabric.
Truly continuous tones can be achieved that are equivalent to photographs, without the use special techniques such as half-screen printing.
The image can be printed all over the entire item, with no difficulty in printing all the way to the edges.
The printer speed is low.
Any creases in the apparel during printing leave blank spots behind