What it is
Polysorbate 60 is a non-ionic surfactant belonging to the polysorbate family, chemically polyoxyethylene (20) sorbitan monostearate. Its main job in cosmetics is to act as an emulsifier, helping water and oil blend into a stable mixture and preventing ingredients from separating. It can also help solubilize small amounts of oily materials such as fragrance or essential oils into water-based products. In sunscreens it contributes to forming and stabilizing the emulsion that carries the UV filters.
Safety & warnings
Polysorbate 60 is a non-ionic surfactant, a class generally regarded as mild relative to ionic surfactants and used widely in oral, topical, and cosmetic products. Reference sources note that people with PEG (polyethylene glycol) hypersensitivity could in principle cross-react with polysorbates because of the shared ethoxylated structure, so individuals with a known PEG allergy may wish to be cautious. For most users at the low levels found in finished cosmetics it is considered well tolerated.
Origin & sourcing
Polysorbate 60 is a semi-synthetic ingredient made through a multi-step process: sorbitol is converted to sorbitan, which is then ethoxylated with ethylene oxide and esterified with a fatty acid. The '60' designation reflects the stearate (stearic acid) fatty-acid portion. The fatty-acid raw material can come from plant or animal sources, while the ethoxylation step is synthetic.
History
The polysorbates are an established class of emulsifiers long used across the pharmaceutical, food, and cosmetic industries, and are widely known by the trade name Tween. Available encyclopedic sources do not document a specific discovery date or inventor for Polysorbate 60.
Questions everyone asks
What is Polysorbate 60 used for in sunscreen?
It is an emulsifier that keeps the water and oil phases blended together so the UV filters stay evenly dispersed.
Is Polysorbate 60 the same as Tween 60?
Yes. Tween 60 is the common trade name for polyoxyethylene (20) sorbitan monostearate, which is Polysorbate 60.
Is it derived from natural ingredients?
It starts from sorbitol and a fatty acid but is ethoxylated synthetically, so it is best described as semi-synthetic.