Press varnishes and coatings serve the same purposes: They coat the printed colours, to help protect them from wear, reducing fingerprinting and scuffing. They also add gloss or, in the case of matte varnishes, glow to the appearance of a printed area. Varnishes have a petroleum base, while coatings usually have a water base. Budget permitting, the decision to use dry-trap or in-line varnish is yours.

Varnishes have the advantage of being quick setting, and of being available in a range of finishes: from matte through high-gloss. Matte varnishes, like matte inks, tend to rub, but this can be offset by adding a wax to the varnish.

Aqueous coatings provide excellent rub protection, sit up on the sheet, dry instantly and dry hard. They also will take longer to yellow than varnishes will. Aqueous coatings can prove invaluable as a substitute for a varnish on a job that is under an extremely tight deadline, since they dry the moment they come off the press.