Fluorescent whitening agent is a kind of fluorescent dye, also known as white dye, is also a kind of complex organic compounds. Its characteristic is to be able to stimulate the incident light to generate fluorescence, so that the dye is similar to fluorite sparkling effect, so that the naked eye to see the material is very white.

According to the chemical structure can be divided into five categories:
Principle of action
Principle of action
1, two styrene type, used for cotton fiber and some synthetic fiber, paper, soap and other industries, with blue fluorescence;
2, the type of the, with the basic structure of the fragrance of beans, used for the game of Lu Lu, PVC plastic, with a strong blue fluorescence;
3, pyrazoline type, used for wool, polyamide, acrylic fiber, with green fluorescent color;
4, benzene and oxygen nitrogen type, used for acrylic fiber and polyvinyl chloride, polystyrene and other plastics, with red fluorescence;
5, benzene two phthalimide, for polyester, acrylic and nylon fiber, with blue fluorescence.