Offset printing inks – Basic
Offset printing inks are compounded especially for use on offset presses. They must be able to withstand reaction with the press fountain solution it encounters on the dampened offset plate. Ideally, the ink on the ink roller should not absorb water (water-in-ink emulsification), nor should the ink break down and combine with the fountain solution on the non-printing areas of the plate (ink-in-water emulsification). Either of these emulsification problems will tend to impair the body, color, or drying qualities of the ink, or cause tinting on the non-printing areas of the plate and printed sheets.
offset printing inks
The offset printing inks used on an offset printing press must be able to carry the full-intended color and covering power to the paper despite the split-film action. This occurs because the offset blanket picks up only a portion of the ink from the plate and delivers only a portion of that to the paper. The film of ink reaching the plate, then, is very thin, and the ink must be able to show its full color and opacity with this film.