The Optical Brighteners are fluorescent substances, that absorb light
in the ultraviolet range and re-emit blue-violet light. This  confers
to the products where applied, a white tonality, the so called optical white.

One of the great advantage of the use of the optical brighteners consists of
the fact that it  prevents the aging aspect /yellowish of the product in cause, once when emitting a bluish light which deletes the yellowish light that the aged product would normally emit. 

The advantages in the use of optical brighteners are extensive to some industrial applications, mainly:

 Plastics.
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