Sorbeth-30 tetraoleate is a tetraester of oleic acid and a polyethylene glycol ether of sorbitol containing an average of 30 moles of ethylene oxide. In cosmetics and personal care products, sorbeth-30 tetraoleate functions as a surfactant and emulsifier.
As a surfactant, sorbeth-30 tetraoleate works by lowering the surface tension between two substances. A surfactant molecule contains one end that is hydrophilic (attracted to water) and one end that is lipophilic (attracted to oil). This allows surfactants to attract and suspends oils, dirt, and other impurities that have accumulated on the skin and wash them away. Due to these properties, sorbeth-30 tetraoleate can be found in many different cleansers and body washes.
Sorbeth-30 tetraoleate 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. With an HLB value of 11.5, sorbitan laurate is soluble in water and gives rise to oil-in-water emulsions.