Guide to Optical Brighteners
optical brightener other names
Optical brighteners, also called optical brightener agents (OBAs) or Fluorescent Brightening Agents (FBA), or fluorescent whitening agents(FWAs) are colorless organic agents that work by emitting visible light when exposed to invisible ultraviolet light. When we say whitening or brightening agents, it also refers to optical brighteners.
how does optical brightener work?
Optical brighteners absorbing ultraviolet (UV) light and re-emitting energy in the form of violet to blue light so that the yellow color of the material will appear white. It worked by optical not by chemical reaction.
The feature of optical brighteners
The chemical structures of these agents contain an aliphatic carbon-carbon double bond, which is sensitive to sunlight, oxidation, weathering, etc. Therefore, these compounds do not have good fastness properties and tend to lose their ability to absorb UV light over periods of time in use.
The presence of high concentrations or improper application or cheaper quality of fluorescent brighteners could lead to yellowing of the material instead of whitening.