What is an underbase?
An underbase is a layer of ink (generally white or other light color) that is printed as a “base” on a dark shirt for other colors to sit on. This gives the top colors more brilliance. Since the underbase is generally a high opacity ink, it is flash-cured before the top colors are printed over it. No only does underbasing slow production, but it is often an extra color that the customer did not plan on – or one that sales did not get enough money for. Underbases are also called an underlay (very common) or a mask (not very common). Contrary to popular belief, underbasing has NOT been around since the beginning of T-shirt printing. In fact in the original version of my Encyclopedia of Garment Printing, first published in 1986, we only touched on the topic. “Back then” we tried to use high opacity inks straight from the can through low mesh counts and hoped that the print would be acceptable. It wasn’t that it couldn’t be done, just that most small shops only had four-color presses and t
An underbase is a layer of ink, usually white, that is printed under the other ink colors when printing dark garments. When printing most colors on dark garments the color of the shirt will show through the ink slightly. For instance, yellow ink printed directly on a royal blue shirt will look very green. To prevent this, a thin layer of white ink is printed, then “flash” dried, and the yellow is printed on top. This gives the top colors a good neutral base and reduces or eliminates the shirt color showing through.
