From Wikipedia, the free encyclopedia
Jump to: navigation, search
Clay earth pigments such as burnt sienna often have a high lightfastness

Lightfastness is a property of a pigment or paint that describes how resistant to fading it is when exposed to light.[1] Light striking a painted surface can alter or break the chemical bonds of the pigment, causing the colors to bleach or change, in a process known as photodegradation.[2] Materials that resist this effect are said to be lightfast.


Some organizations publish standards for rating the lightfastness of pigments and materials. Testing is typically done by controlled exposure to sunlight, or to artificial light generated by a xenon arc lamp.[3] Watercolors, inks, pastels, and colored pencils are particularly susceptible to fading over time, so choosing lightfast pigments is especially important in these media.[1]

See also[edit]


External links[edit]