Gouache paint was first used in the 14th century in the illustrations of illuminated manuscripts. It is very similar in many ways to watercolor paint, and when thinned down a lot, its appearance is almost indistinguishable from watercolor. The major difference between the two is the addition of Chinese white (which is a zinc white rather than a lead white), mixed into gum arabic and then added to the colored pigment. In this way it is also similar to tempera, and is sometimes mislabeled as such, though true tempera actually uses egg yolk.

In the 20th century, Gouache has been used extensively for posterwork, since its matte finish photographs well, and is easy to duplicate with a print. This flat, velvety look is the major visual difference between watercolor and gouache. Most paintings in the medium are works on paper or board, though gouache can also be used on canvas, and has even been used to create cells in animation over watercolor backgrounds.

One of the really cool things about gouache is that it is (to my knowledge) the only opaque paint that can be reconstituted. Paint which is allowed to dry in a plastic watercolor palette can be reconstituted even months later and maintain its quality and lightfastness.

Suggestions for working with gouache:
  • Play around with various opacities.
  • Now try thinning the tones with permanent white instead of water. See? Two palettes for one!
  • Don't overbrush! Gouache tends to do really neat things if you leave it alone, even making your mistakes look super-cool.
  • To create water-resistant colors, mix paint with acrylic glaze medium. This will also keep paint from bleeding up through if you decide to paint washes over background layers.
  • Usually, people use watercolor brushes when painting with gouache, but there are all kinds of nifty effects you can create using different kinds of brushes, too.

Artist's Manual. Angela Gair, ed. Chronicle. San Francisco, 1995.
Pratt Institute, freshman year Light & Color Design class with professor William Sayler