Printing With Just Water

Fountain concentrates, etchs, and gum wet the plate and serve to maintain that all important moisture barrior at the plate which controls where ink is attracted and rejected.

If you use a strong loupe to study ink patches printed with different wetting solutions at varing concentrations, you will notice a significant variation in ink density as a result of sheet show-thru caused by the small voids in the ink and water emulsion that allows the stock to show-tru the ink patch.

As a rule, the greater the concentration of fountain concentrate, the greater the void size.

In addition to sheet show-thru, high concentrations of fountain additives retard ink drying.