Fluorescent whitening agents - the white dyes

摘要

Fluorescent whitening agents (FWA) are colourless to weakly coloured compounds which absorb ultraviolet light and re-emit the absorbed light energy as blue fluorescent light (between 400 nm and 500 nm). The property is reflected in solution as well as on the substrate. They are also called fluorescent brighteners or optical brighteners or white dyes.