Diisostearyl Malate Good Emollient Hydration Diisostearyl Malate description Diisostearyl malate is an ester that functions as an emollient in cosmetics. It is created from malic acid and isostearyl alcohol. This ingredient is most commonly used in lipsticks and has been deemed safe for use by the Cosmetic Ingredient Review board. Related ingredients: Malic Acid