New formulation for highly effective sunscreen

Kurzfassung

Slovenian research institute has developed a new formulation for highly effective sunscreen. The new product shows almost an order of magnitude better UV-filtering ability if compared to the existing commercial products and is much more stable. The product solution is particularly appropriate for preparation of stable and effective sunscreens based on transparent oily media. Researchers are looking for industrial partners interested in further development and license agreement.

Details

A group of Slovenian researchers has developed a sterically stabilised dispersion of a hybrid inorganic-organic material in oil as a preparation for the protection against harmful effects of UV rays. The offered invention refers to a new cosmetic material on the basis of composites of hybrid inorganic-organic coatings on TiO2 nanocrystalline particles or another metallic oxide with increased dispersibility in organic vehicles and decreased formation of free radicals.

The basic nanocrystalline particles of TiO2 and the inorganic coating from the bridged silane are prepared by the sol-gel process. Molecules of an organic steric stabiliser are then covalently bound to the coating of the bridged silane, said stabiliser being selected from one of the following groups of compounds: higher fatty acids, linear polymers, cross-linked polymers, branched polymers and dendritic polymers. The presence of the steric stabiliser prevents the TiO2 particles to agglomerate, improves dispersibility in organic vehicles, increases water resistance of the preparation and allows the use of high concentrations of oily suspensions that provide for a high factor of protection against harmful effects of UV rays.

Innovative Aspects:
All existing sunscreen formulations require one or more stabilizers and other additives to insure physical and chemical stability. Furthermore in case of particulate-based sunscreens (i.e. nanosized) there still remains controversy regarding the safety of such products in terms of light induced radical formation. These can be very harmful as they can damage skin tissue or react with other constituents of sunscreens.

The offered sunscreen formulation resolves both issues by first coating the nanosized TiO2 with hydrophobic protective coating and afterwards grafting short-chain fatty acid stabilizer covalently to the surface of the coated particles. By doing this, supreme oil suspension stability and UV- filtering ability at extremely low concentrations was readily demonstrated along with improved safety due to the protective coating as compared to the existing commercially available products.