(Excerpts from ART HARDWARE: The Definitive Guide to Artists’ Materials, by Steven Saitzyk © 1987)
A waterborne medium is a colorant mixed with a binder suspended in water. The type of binder used defines the type of waterborne medium, or waterborne paint. Tempera, for example, is a waterborne paint whose binder is egg. Ink is a waterborne medium for a pigment or dye with a shellac binder. Acrylics and vinyls are waterborne paints that have a polymer binder. Watercolor is a waterborne paint with a gum binder. The common element is that after the water evaporates, the binder holds the colorant to the applied surface. The primary advantage of waterborne paints and media is the immediacy of the results. In most cases, a finished drawing or painting can be had within minutes. The major drawback is that most artwork produced with waterborne paints or media is less durable and has to be protected from such hazardous atmospheric conditions as humidity and pollution, and from physical damage caused by handling and storage.