Pentaerythrityl Tetraisostearate Good Emollient No known benefits Pentaerythrityl Tetraisostearate at a glance Functions as a thickener, moisturizing ingredient, and binding agent Derived from the fatty acid isostearic acid Used in cosmetics in amounts from 0.1% to 55% Deemed safe as used in skin care products Pentaerythrityl Tetraisostearate description Pentaerythrityl tetraisostearate is a non-aqueous ester that functions as a thickener, moisturising ingredient, and binding agent in skin care products. It is derived from isostearic acid, a type of fatty acid. Pentaerythrityl tetraisostearate is also known as PTIS. It is used in cosmetics in amounts from 0.1% to 55% (the highest concentration is in lipsticks, where it helps impart a glossy look as well as helps to disperse pigments). The independent Cosmetic Ingredient Review panel found that pentaerythrityl tetraisostearate is safe as used in cosmetics, with no irritation or sensitisation reported. Related ingredients: Isostearic Acid