Fluorescent brightener is a kind of fluorescent dye and also known as white dye. It can excite incident ray to produce fluorescence, which can bring bright white effect to dyed substance, and it is classified as color conditioner. It is a fine chemical product in granular from with yellowish shade. Without toxic, is not irritating to human skin, is not harmful to human health, is not harmful to ecological environment and has no side effect on human health.

There are wide range of applications for optical brighteners. In the 1940s, A German company Bayer took the lead in realizing the industrialized production of fluorescent whitening agents. Since then, the production and application of optical brighteners have gradually expanded all over the world.

According to chemical structure, optical brighteners mainly include coumarin type, stilbene type, phthalimide type, pyrazoline type, benzoxazole type, bistriazine type, and other types. Among all these types, the stilbene type has blue fluorescence and has the biggest share in global production and sales. The stilbene based optical brightener is widely used in the European Union, United States, Japan, China and other countries.