Effect of Fluorescent Whitening Agent and Tinting Dye on Optical Properties of Paper

The difference of whiteness, brightness and lightness was clearly explained in this paper by use of a tinting dye and a fluorescent whitening agent which are commercially widely used to make paper look whiter. Other optical properties such as tint, color shade, and color difference were also discussed. It is concluded that in comparing two tinting dyes, lightness (L*) is the most important property to be compared, while whiteness data should be used in caution in order not to surpass its significant range, and a*, b* values can also be used to find the change of color shades together with ${\Delta}E$ as color difference. In comparing two fluorescent whitening agents, whiteness or brightness values are most important to be compared, but lightness values are not suitable for this purpose; a*, b* and color difference ${\Delta}E$ can also be referred, but with less significance.