What it is
C18-38 Alkyl Hydroxystearoyl Stearate is a high-molecular-weight ester wax formed from long-chain fatty alcohols and hydroxystearic/stearic acid components. It is valued for its ability to thicken and structure oil phases, giving sunscreen sticks and lip balms body and a payoff that glides without feeling waxy or draggy. It also imparts a soft, conditioned afterfeel and helps bind oils into a cohesive solid.
Safety & warnings
This large, inert ester wax is generally well tolerated, with a low expected risk of irritation or sensitization. Like other heavy waxes it sits on the skin surface and contributes occlusivity; those who break out easily may wish to take note in rich, balm-type products.
Origin & sourcing
Synthetic ester wax produced by esterification of long-chain fatty alcohols with fatty acid components.
Questions everyone asks
What does this wax ester do in a sunscreen stick?
It structures and thickens the oil phase, giving sticks and balms firmness and a smooth, non-draggy glide while conditioning the skin surface.
Is it derived from animals?
No, it is a synthetic ester wax made by esterifying long-chain fatty alcohols with fatty acid components.