Cetyl phosphate is a complex mixture of esters of phosphoric acid and cetyl alcohol, a fatty alcohol that can be obtained from palm oil. The phosphoric acid portion of this ingredient is very hydrophilic (water loving), while the cetyl alcohol portion of this ingredient is lipophilic (oil loving). This structure allows cetyl phosphate to function as both a surfactant and emulsifier in cosmetics and personal care products.
Surfactants work by attracting and suspending oils, dirt, and other impurities that have accumulated on the skin, which allows them to be washed them away. Cetyl phosphate is used as a surfactant in many different types of cleansers, body washes, soaps, and shampoos. Cetyl phosphate can also be used as an emulsifier in formulations that contain both water and oil components. Mixing water and oil together creates a dispersion of oil droplets in water (and vice versa). These two phases can separate if the product is left to settle. To address this problem, an emulsifier can be added to help the droplets remain dispersed. Emulsifiers improve the consistency of a product, which enables an even distribution of topical skin care benefits.