J. Müller, N. Blosl, K. Schacht
To achieve a sun-kissed and even tan throughout the year without exposure to harmful UV radiation, the use of self-tanning products is very popular among many consumers. The product selection in this segment is diverse, but alternatives to usable active ingredients are low. Most manufacturers typically use dihydroxyacetone (DHA), which causes a tanning reaction in the uppermost skin layer. As the degree of tanning of the skin decreases steadily over time, for longer-lasting effects the self-tanning product must be reapplied at intervals of 3-5 days. Industry is looking for solutions to prolong those intervals. One interesting option is the use of vegan silk to extend the tanning effect. So far, the use of functional, vegan silk was proven to extend the release of fragrances and other actives such as insect repellents. Therefore, the influence of vegan silk on a potential prolonging effect on DHA has been investigated. In formulation, even at pre-set pH values between 4 and 5, for the combination of DHA and vegan silk an excellent stability was determined. Here, it has been proven that the formulation with functional vegan silk can achieve a longer-lasting tan. With increasing silk concentrations tanning results were significantly improved compared to the usage of a conventional formulation without silk.