Flash-cure units, commonly called "flashes," in screen printing are another production element not often considered by customers. But, they are of immense value in the process of giving your design breath.
In a nutshell (and not to bore you with the illuminating, as it were, mechanics behind it all), flashes are simply a curing tool. It is what dries one coat of ink in order apply another layer. Sure, there are some fancy screen printing techniques made possible because of this technology, but still . . . it’s all about drying ink.
In way of example, a shirt that will get several colors would be one in need of a number of flashes. A white under base, initially, is applied (depending on the garment), like scaffolding for the building of the rest of the print. The under base is then flash dried to prevent the white ink from diluting the inks placed on top. Those colors, after applied over the under base, are flash dried as well to allow for highlighting and shadowing inks. Having a dry ink to print on top of ensures these accent colors are crisp and prevents the running together of colors.
Too much “flash,” however, can result in a burned shirt; too little, a sloppy print. In either case, the shirt’s ruined and tossed into the scrap pile for future test printing.
All in all, it’s just another facet of the screen printing world that helps bring to life the vision of your art.