Egg tempera is a semi-opaque, water-soluble and permanent painting medium which is wonderful for fine art painting, restoration and icon-painting. In fact, before the rise of oil painting, egg tempera was the predominant painting medium. Much of the religious panel painting done between the 12th and the 15th century was done in this delicate and subtle medium.
Egg Tempera is perfect for oil painters who need a highly-pigmented alternative to oil painting and its solvents. Its archival characteristics are excellent; paintings in egg tempera do not age or yellow like oil paints, as evidenced by the lasting luminosity and beauty of Renaissance paintings. One thing to keep in mind is that egg tempera is not suitable for use on canvas, because it is less flexible than (for example) oil or acrylics once dry. It is best when painted on a gessoed wood panel or a board (Masonite or MDF). If paper is used, it should be thick (at least 300 gsm) watercolour paper, preferably backed with board or cardboard.
Sennelier Egg Tempera is a modern formulation of egg tempera which is famous as the medium used by Marc Chagall. Sennelier use the same premium-quality pigments in this line of egg tempera as they do in their oil paints, assuring the same unequalled vibrancy and brilliance.
The pigment is bound with an egg emulsion recipe, giving a satin-matt finish that is water resistant when dry. Sennelier egg tempera have the same finish and working qualities as traditional egg tempera, though they do add some oil to the colours as a preservative. (Egg tempera would not otherwise outlast a painting session; Late-Medieval and Renaissance painters - or, more likely, their pupils, assistants or apprentices - would have made their egg tempera paints fresh every day from pigment, egg yolk and water, white wine or vinegar.)
These delicate colours hold their brush strokes, and do not change when dry. They can be worked with a brush or a palette knife (diluted with water) on non-greasy supports. Egg tempera is best applied in thin coats onto a rigid support such as board or gessoed wood panel. Pronounced impasto techniques are not recommended for egg tempera.
Egg tempera paintings look like oil paintings when varnished. It is recommended to give a finished egg tempera painting a coating of charcoal or pastel fixative before applying picture varnish.