Mineral-based sunscreen filters such as TiO2 and ZnO offer a natural solution to UV protection in personel care products compared to traditional organic filters which can be harmful to humans and environment. Among UV filters, zinc oxide (ZnO) is the only globally approved UV filter that can provide broad spectrum UV protection by blocking harmful UVA and UVB rays. However, there are some problems associated with the use of conventional micron-and nano-sized powders in products with sun protection claims which are shown in Table 1 along with the positive attributes of both size scales.
Nanoparticles offer high SPF values and visual light transparency resulting in excellent UVB protection and good visual aesthetics when applied on skin, respectively. On the other hand, such particles are a potential threat to environment and the risk of agglomeration due to their high surface area is greater compared to that of non-nano filters. 2 Although micron powders are more eco-friendly than their nano size counterparts, the UV protection per mass of micron powders is lower and an undesirable whitening effect on application is usually inevitable. MicNo-ZnO® particle technology is tailored fort he formulators considering all the above-mentioned aspects of manufacturer, consumer and regulatory needs via offering the advantages of both nano and micron scale while limiting their disadvantages due to their unique platelet-shaped design.
Formulators can choose to work with dispersions, uncoated and coated forms of MicNo ZnO when designing formulations for specific needs. MicNo ZnO can be used as the only active filter in natural formulations or can be used with organic filters to further increase the UV protection performance.