Figure 2. Absolute color fading ∆Efading of a) single-bleached or b) double-bleached Caucasian hair tresses colored, then shampooed and/or exposed to UV; shampooing was done with a commercial color protection brand.

However, with dyed double-bleached tresses (see Figure 2, bottom), the impact of UV alone was negligible, with only a slight additive effect over shampooing.