The Adsorption Behavior And Photoprotection Effect Of UV Filter Absorbed On The Surface Of Huma Hair

Healthy hair is everyone’s pursuit, in addition to the daily processing damage of hair caused by mechanical damage, the damage of UV on the hair also cannot be ignored. Many research about hair damage by tensile damage or chemical damage have been done, but the reacearch about photoprotective effect of UV filters on the hair is missing. In this paper, four kinds of UV filters with different structure were selected as the object to study, including methoxydibenzoylmethane (BMBM), octylmethoxycinnamate (OMC), benzophenone-3, and octyl salicylate. This report presents the adsorption behaviors and effects of these filters on hair cuticles. The main results are below:1. The adsorption behavior of UV filters in alcohol solution. The results reveal that all of these UV filters can be adsorbed on the surface of hair fiber, and the adsorption equilibrium time was about lh. The adsorption rate of octyl salicylate is faster than the other ones, the adsorption kinetics of the filters is comparable with a pseudo-second-order kinetic model and that their adsorption isotherms match the Freundlich adsorption model.2. The adsorption behavior of four kinds of UV filters in the hair care system. Including: the selection of emulsifiers and oil, the adsorption quantity of each UV filetr with different concentrations, the relationship between the time and the adsorption quantity of UV filters, and the relationship between the time and the desorption quantity of each UV filters.The adsorption competitive of silicone and the cationic on the surface hair were studied as well. The experimental results show that:capric triglyceride has a good dispersion of UV filters, cetearyl alcohol/coco glucoside have a good emulsification at the hair care system containing UV filets. In this hair care system, adsorption of UV filters occurred fairly rapidly and reached equilibrium after approximately 1 h, and the deadsorption time is about 30min, the, octyl salicylate showed better adsorption capacity than the other three kinds of filters, OMC adsorpted worst. The adsorption quantity decreased gradually as the adding of silicon. In the alcohol system, the competitive adsorption effect of cationic surfactant is not obvious.3. The photoprotection effect of UV filters for the hair fibers. Including:protein degradation, lipid peroxidation, and surface changes in hair exposed to irradiation. The results show that:four kinds of filters are all have a photoprotection effect, the photoprotection effect of UVB fiters are better than that of UVA filters, Octyl salicylate on protein and lipid hair protection function is better than that of octyl methoxycinnamate, the protection effect on tryptophan is different, but not so obvious, when the illumination time increase the difference becomes less obvious, SEM images obtained showed that application of UV filters to hair fibers improves the hair surface compared with the open cuticles of the control samples.