Egg tempera is a type of paint made by adding pigments to a mixture of egg yolk and water. It is said to be one of the oldest, most versatile, and most durable methods of painting. It dates back to prehistoric times,
It is generally unaffected by humidity and temperature changes. Tempera emulsions form their own protective surface film and do not darken with age as oil paint films do. Like acrylic paint, egg tempura dries rapidly and become water-resistant; meaning one application of the paint can be followed up quickly with another without disturbing the layer underneath.
Egg tempera can be applied in washes just like water-colour only they work better in that being water resistant they don’t blend or bleed and you can see the colours beneath better e.g. a yellow wash can be applied over a blue wash, and the result will be a yellow-blue or green. When applied in thin layers the results are more transparent than transparent watercolour; when applied more thickly the results are opaque like gouache.
The term "tempera" comes from temper or tempering, which means to bring something to a desired, or usable, consistency. In this case, the something is a pigment.
Another interesting aspect of Egg Tempura is that after the tempera painting is completed, it can be burnished or polished with a polished agate stone or spoon to add depth and brilliance and to increase transparency, or it can be varnished to look like an oil painting.
To make Egg Tempura paints you need to make the pigment part into a paste with a small amount of water. (Some pigments, such as alizarin crimson, Prussian blue, and some blacks do not mix readily into a water paste and so a small amount of alcohol must be added as a wetting agent.) A fresh hen's egg (The eggs you normally buy in supermarkets are often several weeks old) and distilled water are used for the binder. To prepare the binding medium, an egg is cracked and the yolk is separated from the white. The yolk is dried by rolling it in the hand or by placing it on a sheet of absorbent paper. You then cut with a knife and the liquid needs to be run off into a glass jar. Distilled water is added to bring the egg to the consistency of thin cream. Next you add the pigment paste with the egg yolk binder and your egg tempura paint is ready to use. A better mix has oil in it, which makes it less prone to cracking and is easier to work with, especially on flexible supports like canvas or paper. You can also make the paint film thicker because of this. Egg-oil emulsions produce a glossier finish than pure egg tempera and dry harder. Like egg tempera, an egg-oil emulsion dries very rapidly, in seconds in thin washes, and can be painted over almost immediately.
You can buy ready made version of egg-oil emulsion temperas which come in tubes and can be purchased from your local art supply store. After thinning with a little distilled water, the paint can be used straight from the tube, saving you the inconvenience of having to prepare the colour from the raw materials before each painting session.
Some artists who make their own will use what is termed the lazy person’s tempura, where they use the whole egg with linseed oil. The egg, oil, and pigment are mixed in equal portions. Although simpler to make this egg-oil emulsion dries relatively quickly, producing a hard, but slightly cloudy, surface, so you have to decide if that is the finish you want to have.
Egg tempera is a method of painting which was largely popular in the early Renaissance. Botticelli's Birth of Venus (Otherwise known as the Venus on the half-shell) and other, much less famous-paintings were done in the medium.
A link for those interested in wetting agents https://coatings.specialchem.com/supplier/bruggemann where you will find a technical datasheet available for download
Posted: Friday 23 April 2010