Which chemical and physical factors affecting the light fastness of pigments and dyes?
These following factors affect the light fastness of pigments and dyes: • The concentration of dyes and pigments. • Chemical as well as physical structure of these substrates. • Distribution of wavelength of incident radiation. • The atmospheric conditions like the humidity in the atmosphere and percentage of contaminants. • Distribution of wavelength of the incident rays. • The rate of diffusion of the volatile substances in the polymer. NOTE: The lightfastness of the pigments and dyes do not depend upon the pigment or dye, but depends upon the whole system.
