An ink that dries, or "sets" by precipitation of the pigment out of the vehicle. Moisture-set inks typically utilize glycol-based vehicles. Water-insoluble resins are dissolved in a water-soluble solvent, usually glycol (an alcohol also used in antifreeze). When moisture comes in contact with this type of vehicle, the glycol is dissolved, and the resin precipitates out, dragging the pigment with it. Glycol vehicles are commonly used in letterpress printing, and their lack of odor makes them useful for printing food packaging. Moisture-set ink in which the moisture is provided in the form of water vapor or steam is called steamset ink. (See Glycol Vehicle.)
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