In Vitro Visible

Considering that Visible (VIS) light from 400 to 700 nm (mainly from the sun light) also contributes to skin damage via induction of radical protection, a relative protection can be effective whatever the benefits or harmful effect of VIS on the skin and should be assessed in a reliable manner. Therefore, this innovative in vitro method consists in evaluating the Visible protection levels expressed by the VIS-CW (UV/VIS balance) and the % VIS (percentage of intensity of VIS protection) from a sunscreen product through the spectrum (from 290 nm to 700 nm) measured by means of a spectrophotometric method. To take into account any potential photo-unstability, the product was pre-irradiated before measurement. Finally, this method relies on the use of in vivo SPF results for scaling the absorbance curve.