The meaning of this word is to “temper”, that is to mix the different colors with binding substances such as water, egg, glue, etc. Each binder creates different effects: the “lean tempera”, consisting of water and vegetable / animal glues, when it dries, it clears up; the “tempera fat” is made up of oily substances and therefore it is confused with oil painting and therefore lends itself to having many more colors; the “pure egg yolk tempera”, which dries very quickly, creates intense and bright colors and if you want to have lighter colors just add milk, wine or beer. This instrument is very resistant, so much so that it does not discolour over time and is almost waterproof, with a generally very high seal. It is also opaque, so you can make subsequent corrections.
Generally synthetic brushes or brushes with natural bristles (ox hair), 01/03 and Michelangelo sheets are used.