A variety of ink formulated for use in waterless lithography, a type of offset lithography that uses silicone rubber (or other silicone compounds) in non-image areas of the plate to repel ink, thus eliminating the need for a dampening system as in traditional offset lithography. Despite the advantages of waterless printing, a disadvantage is toning of the non-image areas of the plate, typically due to heat effects; for example, a 10ºF rise in ink temperature can cause toning. Waterless inks are designed to resist temperature fluctuations. Temperature-controlled ink rollers are also used on waterless presses to prevent such problems. Waterless inks are also similar in composition to letterset inks. (See also Letterset Ink.)
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