Emulsifier

PEG-20 Glyceryl Triisostearate

Reviewed by Kate · Last updated 18 Aug 2026

Also known as: Glycerin, Isostearic Acid, Polyethylene Glycol

An ester of the fatty acid isostearic acid combined with polyethylene glycol and glycerin | May be animal-derived or synthetic

Addresses

Dehydration

What Is PEG-20 Glyceryl Triisostearate?

PEG-20 glyceryl triisostearate is an ester of the fatty acid isostearic acid combined with polyethylene glycol and glycerin. It may be animal-derived or synthetic. It is commonly used as an emulsifier and mild cleansing agent, where it’s often seen in oil-based formulas due to its ability to help oily ingredients rinse from skin without leaving a greasy residue. It is noted for offering skin-softening properties as well.

Some suppliers report this surfactant works very well to cleanse particulate matter (a form of airborne pollutants) from skin.

In rinse-off products, such as facial cleansers or body washes, PEG-20 glyceryl triisostearate is used up to 20% concentration. For leave-on formulations, such as moisturizers and sunscreens, it typically tops out at 5%.

This ingredient has undergone extensive toxicology review and is considered non-irritating and safe as used in rinse-off or leave-on cosmetics. PEG-20 glyceryl triisostearate’s high molecular weight keeps it from penetrating past skin’s surface.

Clinical Evidence & References

Published Research

  • Toxicological Research, June 2015, pages 105-136 [https://link.springer.com/article/10.5487/TR.2015.31.2.105]

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