Fading. A lessening of the intensity of a color
by exposure to sunlight or air. Chemically unstable dyes or pigments undergo changes
which cause alteration in color. When water-based pigments dry out, they lose
their gloss or luster and are said to have faded. However, when oil-based pigments
lose their luster, the chemical process is different and therefore the term "dulling"
is used. Varnish can be applied to a surface with dulled pigment to restore the
original gloss. |