A type of ink vehicle—the fluid carrier of the ink pigment—that dries by evaporation and absorption of the vehicle. Also known as "watercolor" inks, these are produced by dissolving gum arabic in water, glycerine, or other solvent, and deposited on the substrate, where absorption and evaporation remove the solvent, leaving the gum and pigment behind. Watercolor inks are not widely used, except for novelty applications. (See Vehicle.)