Silica Silylate
Silica silylate is silica surface-treated with trimethylsilyl groups so it feels silkier and disperses better into oil-based formulas; it works as an anti-caking and viscosity-control agent in pressed powders, foundations, and other makeup. CIR reviewed it in the same assessment as silica dimethyl silylate and trimethylsiloxysilicate and concluded it's safe as used, with the same caveat that the finished product should be formulated not to irritate the eyes or respiratory tract.
Products with Silica Silylate
References
Cosmetic information for general education, not medical advice. A verdict is a reading of the published evidence, never a guarantee for your skin: any ingredient can irritate someone, so patch test new products and see a professional if you react. Concern is graded on cited evidence, never on hazard-score lists. See how we score.