A type of ink vehicle—the fluid carrier of the ink pigment—that dries by evaporation of the vehicle, rather than by absorption of the vehicle into the substrate or by oxidation. In solvent-resin vehicles, a low-boiling point solvent is rapidly evaporated out of the ink, either with or without the application of heat (as in heatset ink), leaving the hardened pigment on the substrate. The solvent may be composed of hydrocarbons modified by the addition of gums and rosins (as in gravure inks), alcohols, water, or other volatile solvents (as in flexographic inks, although the composition of the substrate itself primarily determines the solvent), or somewhat less volatile (in other words, evaporating at a higher temperature) petroleum solvents in which are dissolved rosin esters or hydrocarbon resins (as in heatset inks for letterpress and offset lithography, which handle well on the press, and dry extremely quickly with the application of heat). (See Vehicle.)
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