Ingredients and Composition: What is in Tempera Paint

what is in tempera paint

The Annunciation - tempera on wood -

The Annunciation - tempera on wood -, Filippo di Tommaso Lippi

Tempera paint consists of finely ground pigments dispersed within a water-soluble binder. The most common traditional version, egg tempera, uses egg yolk mixed with distilled water to create a stable emulsion. Other variations include casein paint made from milk protein and distemper which utilizes binders like cornstarch or gum arabic.

The composition of the medium depends on the specific binder used to hold the pigment in suspension. Traditional egg tempera is a permanent, fast-drying medium. In contrast, modern school-grade tempera or poster paint is designed to be temporary and is easily removed from surfaces with water.

The primary ingredients include:

• Powdered pigments
• Egg yolk (in egg tempera)
• Distilled water
• Milk protein (in casein paint)
• Synthetic PVA (in polyvinyl acetate tempera)

Egg tempera vs modern poster paint differences

Egg tempera is a permanent, durable medium that dries into a hard, insoluble film, whereas modern poster paint is a temporary, water-soluble medium. Egg tempera is characterized by high color saturation and a matte finish, while modern school tempera lacks eggs and is designed for easy cleanup.

The technical properties of these mediums differ significantly:

• Egg Tempera: Fast-drying, permanent, requires rigid supports, and is applied in translucent layers or cross-hatching.
• Poster Paint: Non-permanent, easily washed from clothing, and lacks the long-term stability of protein-based binders.

Traditional egg tempera requires meticulous preparation, as the ratio of pigment to binder must be adjusted based on the mineral source of the color. This process creates a surface where light penetrates microscopic, translucent strata to produce internal luminosity. Modern poster paint does not possess this structural depth.

Why tempera requires rigid boards

Tempera is not a flexible paint and requires stiff boards as a substrate to prevent cracking. Because the binder dries into a hard, non-elastic film, any movement in a flexible canvas can cause the paint layer to fracture or delaminate from the surface.

The lack of flexibility is a defining characteristic of the medium's physical structure. Unlike oil paint, which remains somewhat flexible, egg tempera is rigid. This necessitates the use of stable, non-moving supports such as wood panels. For example, Fra Filippo Lippi’s The Annunciation (c. 1440) is executed as tempera on wood to ensure the longevity of the detailed Renaissance work.

To prepare these rigid supports, artists often apply a heated gesso mixture. This coating provides the necessary smooth, stable surface required for the meticulous application of thin, translucent layers of pigment.

Common additives in traditional tempera

Traditional egg tempera can include various additives to alter its scent, texture, or drying properties. Common additives include liquid myrrh to provide a pleasing odor, as well as oil and wax emulsions. These substances are integrated into the egg yolk and water vehicle during preparation.

In manufactured egg tempera, gums are often included to act as dispersants for the pigment. The specific ratio of ingredients is critical to the final finish:

• Too much egg yolk: Results in a greasy appearance.
• Too little egg yolk: Results in a chalky appearance.
• Correct ratio: Produces a slightly glossy finish.

The application of these additives requires precision. Artists often apply the paint using small, translucent strokes, cross-hatching, or overlays of glazing to build up color density without the use of heavy, thick applications that might lead to cracking.