Polyhydroxystearic Acid is a polimer (polyester) from 12-hydroxystearic acid units, a soft waxy substance derived from natural raw materials such as castor oil. It is a viscous liquid at ambient temperatures. Polyhydroxystearic acid is an all-vegetable-derived multifunctional ingredient in skincare applications used as a dispersant for pigments and UV-reflecting minerals, emulsion stabilizer, thickener, and film former.
Improving consistency and sensory profile of formulation, Polyhydroxystearic Acid provides creamy textures and gel-like thickness for oil-based preparations. In sunscreens and decorative cosmetics, it provides even distribution, coating, and wetting of pigments and minerals such as titanium and zink oxides without a sticky or greasy feel and whitening.
Depending on concentrations, Polyhydroxystearic acid decreases viscosity and delivers a wide range of thicknesses from pasty texture creams and solid lipsticks to liquid lotions and sprayable aerosols. Its gloss and solubility profile strongly suggest its use in color cosmetics.
Polyhydroxystearic acid can complex water via hydrogen bonding on the skin surface and can absorb moisture. It is a safe and chemically inert ingredient for skincare applications reviewed by CIR (Cosmetic Ingredient Review) experts panel in 2022.