Synthesis of cosmetic grade TiO_2-SiO_2 core-shell powder from mechanically milled TiO_2 nanopowder for commercial mass production

摘要

TiO2nanoparticles as an active sunscreen ingredient generate reactive oxygen species (ROS) upon UVA irradiation which is cytotoxic, genotoxic and potential to damage the DNA. The health concern and potential risks from TiO2can be mitigated by shielding the particles through the suitable coating. Considering the advantages of SiO2, SiO2coated TiO2nanoparticles can be a potential material which can replace TiO2for thickening, whitening, lubricating, and sunscreen ingredient in cosmetics. This article reports the synthesis of cosmetic grade TiO2-SiO2core-shell nanopowder from mechanically milled TiO2nanopowder for commercial mass production. From commercial TiO2nanopowder was fabricated through size reduction by nanoset milling. Followed by the fabricated TiO2nanopowder coated with SiO2through sol-gel technique. A suitable optimum condition was explored for cosmetic grade TiO2-SiO2core-shell nanopowder. Various physical properties and optical properties were analyzed. Synthesized of cosmetic grade TiO2-SiO2core-shell nanopowder found to be at 100 nm size, with a homogeneous SiO2coating having UVA protection factor 39 and sun protection factor (SPF) is 42. From the size, safety, and SPF perspective it can be an excellent cosmetic grade powder and from process simplicity perspective it can be commercially viable.