Alumina (Aluminum Oxide)

Alumina is an inorganic mineral material (aluminum oxide) used in cosmetic formulations as a multifunctional opacifying, bulking, and texture-enhancing ingredient, and as a key surface treatment/coating for pigments and UV filters. In color cosmetics, it can improve powder flow, slip, and wear, helping enhance adhesion and a smoother, more refined finish. In sunscreens and pigmented systems, alumina is frequently used to coat mineral UV filters and pigments (e.g., titanium dioxide) to improve dispersion, reduce reactivity, and enhance stability and sensory performance, including reduced chalkiness and better payoff. It may also contribute a mild soft-focus effect by optimizing light scattering when incorporated into powders and primers. Typical applications include foundations, concealers, face powders, eyeshadows, sunscreens, and other pigmented or mineral-based formats, with use level and performance depending on particle size, treatment type, and compatibility with the overall formulation system.