Pad printing utilizes a flexible silicone rubber transfer pad that picks up a film of ink from a photo-etched printing plate and transfers it to a three-dimensional part surface. The unique properties of silicone rubber allow distortion-free, single or multi-color images to be applied to flat, curved, or tapered surfaces with excellent definition and opacity. Pad printing inks, specifically formulated to adhere to various substrates, are used to decorate metals and ceramics as well as a wide range of plastics. Ink viscosity is controlled by use of a closed-cup ink reservoir, which is moved over the etched plate by the printer’s mechanism. For multi-color decorating, two or more pads may apply additional images and colors to the part, while accurate image registration is maintained throughout the printing cycle. This precise repeatability also permits application of the same image for increased opacity.