Intonaco layer

BC in Egypt arriccio layer to smooth surface and intonaco layer of gypsum plaster form surface on which pigment in binder are applied. Binder is usu y gum arable (referred to as tempera binder) plasticized with honey... 

In the past the famous painters used thin layer of wet plaster to paint on it, known as intonaco. The pigments sink into this layer so that the plaster itself becomes the medium holding them, which accounts for the excellent durability. 

Today, thanks to scientific analysis (supporting the traditional and historical sources), it is possible to verify and identify the ingredients of the secret receipes that an artist used to prepare the own imprimitura [ll]. In a fresco painting, the ground is the so called arriccio , a layer of fairly coarse plaster applied to the wall before the intonaco (the smoother top layer of plaster that forms the painting surface). 

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