What it is
Cetyl Phosphate is an anionic emulsifier made by esterifying the fatty alcohol cetyl alcohol with phosphoric acid. It is widely used to create stable oil-in-water emulsions, making it well suited to lotions and creams that combine oily UV filters with a water phase. It is often neutralized in formula and is valued for producing light, well-structured emulsions with a pleasant skin feel.
Safety & warnings
Cetyl Phosphate is generally well tolerated as used in cosmetics. As an anionic surfactant it can be mildly irritating at high concentrations or low pH, but at typical neutralized use levels it is considered low risk for irritation and sensitization.
Origin & sourcing
Synthetic, produced from cetyl alcohol (a fatty alcohol that can be plant- or petroleum-derived) and phosphoric acid.
Questions everyone asks
What does cetyl phosphate do?
It is an emulsifier that helps blend oil and water into a stable cream or lotion, commonly used to carry oily UV filters in sunscreen formulas.
Is cetyl phosphate harsh on skin?
At the neutralized levels used in finished products it is generally mild and well tolerated, though like many surfactants it can be mildly irritating only in high concentrations.