UV protection of artificially coloured hair using a leave-on formulation

The present article describes the use of a polymeric organosiloxane sunscreen (SLX), to protect the artificial colour of human hair upon simulated solar radiation. The cosmetic vehicle used to treat the coloured hair is a leave-on formula. It has been found that the semi-permanent and permanent colours can both be degraded when exposed to simulated sunlight. The efficacy of SLX to protect the artificial colours was compared to ethylhexyl methoxycinnamate (EHMC), the most often used UV filter in marketed sun sprays. SLX (1-5%) was more effective than EHMC (1-5%) to protect the artificially coloured hair, especially by protecting the lightness of the hair.