UV filters for hair protection

Synopsis Hair damage, caused by sunlight, and the possibility to protect hair against sunlight by means of cosmetic formulations was studied. For this, five UV‐filters were tested: benzophenone‐3 (UV‐A/UV‐B); benzophenone‐4 (UV‐A/UV‐B); phenylbenzimidazole sulfonic acid (UV‐B); butylmethoxydibenzoylmethane (UV‐A); octyl dimethyl PABA (UV‐B). The stability of the UV‐filters was tested as pure substances as well as in two cosmetic formulations: a setting lotion and a shine spray. The degree of decolouration and stress strain behaviour were determined. The benzophenones had the best protection ability both on colour and on morphology. Stability data and UV‐spectra are discussed.