What it is
Sorbitan oleate is a non-ionic surfactant and emulsifier made by esterifying sorbitan with oleic acid. Because part of the molecule is water-compatible (from sorbitan) and part is oil-compatible (from the oleic acid chain), it positions itself at oil-water interfaces and forms a protective layer around dispersed droplets, helping keep emulsions from separating. It has a low HLB value (about 4.3), which makes it well suited to stabilizing water-in-oil emulsions and is often paired with a higher-HLB partner such as a polysorbate. It also acts as a wetting and dispersing agent, helping spread insoluble particles such as mineral UV filters or color pigments evenly through a formula.
Safety & warnings
Cosmetic references rate sorbitan oleate as non-irritating, and it is a long-established emulsifier also permitted in food (E494). Its comedogenicity is rated moderate, so it is one of several factors worth noting for people who are very acne-prone, though comedogenicity ratings of single ingredients do not reliably predict how a finished product behaves.
Origin & sourcing
It is a semi-synthetic ingredient produced by combining sorbitan, a dehydrated sugar alcohol derived from sorbitol, with oleic acid, an unsaturated fatty acid. The commercial material is an amber liquid in which oleic acid predominates, with smaller amounts of other fatty acids such as linoleic, linolenic, and palmitic.
Questions everyone asks
What does sorbitan oleate do in a sunscreen?
It is an emulsifier that keeps the water and oil phases blended, and it helps disperse insoluble particles such as mineral UV filters and pigments evenly through the formula.
What is sorbitan oleate made from?
It is made by reacting sorbitan, a sugar alcohol derived from sorbitol, with oleic acid, a fatty acid. The result is a non-ionic emulsifier also known as Span 80.
Is sorbitan oleate safe?
It is a long-used cosmetic and food-grade emulsifier rated as non-irritating in cosmetic references. Its comedogenicity is rated moderate, which acne-prone users may wish to note.