Trimethylolpropane Triisostearate

This is a triester made from trimethylolpropane and isostearic acid, used as a thick, cushiony emollient in lipsticks, creams, and makeup to soften texture and add slip. It belongs to a well established family of fatty ester emollients with a low irritation history, though a dedicated CIR report specific to this ester was not located, so the evidence here leans on its close chemical relatives rather than ingredient specific testing.

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.