Waterless printing is an offset lithographic printing process that eliminates the water or dampening system used in conventional printing. It uses silicone rubber coated printing plates and specially formulated inks, and typically a temperature-control system is integrated into waterless presses.

Waterless vs. Conventional Printing Plates

Waterless offset presses do not use dampening solution to keep the plate's nonimage areas free of ink. These presses function because the plate's nonimage areas consist of a layer of silicon that repels ink. A waterless press resembles a conventional offset press, except the dampening system might be missing. A more common design, however, includes a dampening system to allow the press to function conventionally when needed. Direct imaging (digital) offset presses are waterless, with no dampening system. Waterless offset inks have a higher tack and viscosity (thickness) and are generally stiffer than conventional offset inks. The temperature of the inks must be strictly controlled to maintain the correct viscosity because the plate surface is designed to repel inks of a specific viscosity. This temperature distinction is achieved by running chilled water through tubing in the hollow cores of two or more vibrating rollers in the ink train on the printing press.