Po
Polyhydroxystearic Acid
Polyhydroxystearic Acid
A dispersing agent that coats mineral particles like titanium dioxide and zinc oxide so they spread evenly instead of clumping.
What it does
Polyhydroxystearic acid is used mainly as a dispersant and wetting agent. It coats the surface of mineral particles — especially the titanium dioxide and zinc oxide in mineral sunscreens and pigments in makeup — so they stay separated and spread into a smooth, even film rather than clumping or streaking. It is a formulation aid that improves how a product applies, not an active on the skin.
Also known as
phs
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