The drying agent used accellerates the oxydation process. Heat helps to activate drying processes depending on oxydation. Photogravure inks dry by evaporation and by penetration. With cellulose and ethylcellulose base inks, fluorescent inks as well as some synthetic inks and some water base inks, drying is achieved by evaporation and penetration. Clycerophtalic inks dry by oxydation after the evaporation of the solvent they contain.
Different inks have different drying times.
Typographical inks are fast drying for machine printing and medium fast drying for manual impressions. This is also true for lithographic and offset inks which are fast drying for machine printing. The drying speed of these inks is calculated in function of the speed of the machines used. The inks used for manual intaglio printing are fairly quick drying. The inks used in silkscreening are more delicate and somewhat problematical because their drying process must be slowed down so that they do not dry in the meshes of the screen.