Fugitive pigments
From Wikipedia, the free encyclopedia
Fugitive pigments, are non-permanent pigments - pigments that lighten in what is understood, said or defined to be a relatively short time when exposed to light. Fugitive pigments are present in types of paint, markers, inks etc., which are used for temporary applications.
While paintings are often done with permanent pigments, painters have made work wholly or partially with fugitive pigments for a number of reasons: ignorance as to the permanence of the pigments, prioritising the appearance of the colours one can get with fugitive pigments over permanence, or the desire to have a painting change in appearance over time.
[edit] Why pigments fade in sunlight
Light is composed of particles called photons. These photons carry energy, and can cause significant chemical damage to typical molecules that absorbs them. Many colored molecules are relatively fragile and are damaged by photons of ultraviolet light. The portion of a pigment molecule that gives it its color is called a chromophore and is usually the most fragile part of the molecule. Destroying its chromophore will often leave a pigment molecule colorless.
