Hickies are printing defects visible as small voids in a printed ink film where ink does not transfer on the plate or blanket. Doughnut hickeys appear as a white void with a solid spot in the center. Doughnut hickies are caused by non-water absorbent particles such as dried ink, rubber pieces from ink rollers, or pressroom dirt. The contaminate particle accepts ink, the raised particle transfers the ink, and no ink transfers around the contaminate particle's edge, creating a ring or doughnut shape. Void hickeys appear as white spots and are typically paper-generated. They absorb fountain solution and repel the ink, resulting in a white spot. Preventing hickies involves keeping a clean press area, including overhead lighting and duct work.