Gouache

Lore & Background

Gouache, also known as body color or opaque watercolor, is a water-medium paint composed of natural pigment, water, a binding agent such as gum arabic or dextrin, and sometimes an inert material. It is designed to be opaque. The paint is similar to watercolor in that it can be rewetted and dries to a matte finish, and it can become infused into its paper support. However, gouache is modified to be heavier and more opaque than watercolor, with larger pigment particles, a higher pigment-to-binder ratio, and often an additional white filler like chalk, which gives it greater reflective qualities. When wet, gouache appears one value but generally dries to a different one—lighter tones usually dry darker, and darker tones tend to dry lighter—making color matching across sessions challenging. Its quick coverage and total hiding power allow for more direct painting techniques than watercolor, a quality exploited in plein air painting and by artists like J. M. W. Turner. Commercially, gouache is widely used for posters, illustrations, comics, and design work; most 20th-century animations employed it for opaque color on cels, with watercolor used for backgrounds. It can be applied with a brush, airbrush, or on unusual surfaces like Braille paper or cardboard. A notable variation is acrylic gouache, which uses an acrylic-based binder instead of gum arabic, dries to a matte, opaque, and water-resistant finish, and contains additives to ensure that matte quality. Historically, a form of gouache with honey or tragacanth gum was used in Ancient Egyptian painting, and European illuminated manuscripts as well as Persian and Mughal miniatures are predominantly examples of gouache, though often mischaracterized as watercolor. The English word derives via French from the Italian *guazzo*, meaning "mud," originally applied to a 16th-century practice of applying oil paint over a tempera base. In 18th-century France, the term was used for opaque watermedia. During that century, artists often mixed gouache with pastel for fine details, and in the 19th century, industrially produced watercolors in tubes included a "Chinese white" tube for this purpose. Later, mass-produced "poster paint" using a cheaper dextrin binder replaced older hide glue or size paints.

Reader's Guide

Gouache is significant for its opacity and versatility, allowing direct painting techniques and complete hiding power. It is similar to watercolor in being rewettable and drying to a matte finish, but differs in having larger pigment particles, a higher pigment-to-binder ratio, and often an additional white filler such as chalk. This makes it heavier and more opaque, with greater reflective qualities. Gouache dries to a value that differs from its wet state, which can make color matching difficult. It is widely used by commercial artists for posters, illustrations, comics, and design work, and was used in most 20th-century animations for opaque color on cels. A newer variation is acrylic gouache, which uses an acrylic-based binder and dries to a water-resistant, matte surface.

Did You Know?

• Gouache has been used for over four thousand years, with a form used in Ancient Egyptian painting.
• The English word 'gouache' derives via French from the Italian 'guazzo,' meaning 'mud'.
• Gouache generally dries to a lighter value than when wet, regardless of the original tone.
• A relatively new variation is acrylic gouache, which uses an acrylic-based binder and dries water-resistant.

Naming Confusion and the Tempera Connection

The term "tempera paint" in everyday usage often points to a product that is actually closer to gouache than to the classical egg-based medium the name suggests. In certain regions, a distemper formulation built from pigment suspended in cornstarch, gum arabic, or other plant gums is marketed under the label "tempera paint," yet its visual result aligns more closely with gouache than with traditional egg tempera. This mislabeling traces back to the Italian phrase dipingere a tempera, meaning "paint in distemper," which itself derives from the Late Latin distemperare, "mix thoroughly." The word tempera thus carries a broad, somewhat ambiguous heritage that has allowed multiple distinct paint types to share one name, creating persistent confusion between genuinely egg-based tempera and the gouache-like distemper products found in art supply stores.

Binder Composition and the Chemical Divide

What distinguishes the gouache-like distemper from classical tempera lies primarily in its binding medium. Where egg tempera relies on the yolk of a chicken egg—diluted with water, sometimes white wine, or a small quantity of vinegar as a preservative—the gouache-adjacent distemper turns to entirely different agents: cornstarch, gum arabic, and various other plant-derived gums. These binders produce a paint whose behavior on the surface and its final visual character differ markedly from the layered quality of egg tempera. The result is a medium that, while water-soluble and fast-drying like its tempera relatives, achieves an opacity and flatness that the source material describes as "more like gouache." This compositional distinction is the single most important factor separating the two, even though casual naming conventions routinely blur the line between them.

Visual Character and Surface Behavior

The available evidence makes clear that the visual effect of the distemper family of paints—those built on cornstarch, gum arabic, and other gums—is "more like gouache" than like the egg-tempera tradition. This implies a surface quality that is flatter and more uniform, standing apart from the subtle granular texture that characterizes egg tempera laid in thin, layered strokes on rigid panels. Egg tempera, by contrast, demands stiff boards because it is not a flexible paint; applied to canvas it cracks and chips. The gouache-like distemper, freed from those structural constraints by its different binder chemistry, can sit on a wider range of supports and produce the kind of even, opaque color field that the term "gouache" evokes. The distinction is not merely technical but perceptual: one medium builds through translucent layers, the other declares itself in solid, matte planes.

A Place Within the Water-Soluble Family

Gouache occupies a specific niche within the broader family of water-soluble, fast-drying painting media. The tempera umbrella, as the source material outlines, encompasses egg tempera (yolk as binder), casein paint (milk protein), polyvinyl acetate tempera (synthetic PVA), and the distemper or poster paint category whose visual result most closely resembles gouache. Each of these shares the fundamental property of being permanent and water-soluble, yet they diverge in binder, handling, and final appearance. The fact that a cornstarch-and-gum distemper is "often confusingly referred to as tempera paint" while its look is "more like gouache" underscores how the boundaries between these media are both chemical and cultural. For the working artist, recognizing which binder is at work—and what visual character it delivers—remains essential to choosing the right tool for a given surface and effect.