The stability of a colour, determined experimentally under UV light. Coloured pigments can fade due to attack by UV rays from the sun, which causes a chemical reaction within the pigment and a change in its structure which appears as gradual fading over a period of time.
How much light exposure paper or film can withstand without losing original characteristics. 
No loss of color due to exposure to light, heat or weathering.
No loss of color due to exposure to light, heat or weathering.
No loss of color due to exposure to light, heat or weathering.