Polyquaternium is a term that the INCI (International Nomenclature of Cosmetic Ingredients) uses to generically describe a polymer that has been modified by a process known as quaternization. Polyquaternium-10 is produced through quaternization of hydroxyethylcellulose, a modified cellulose polymer. Polyquaternium-10 is a linear polymer with small, positively charged side groups along the backbone. Polyquaternium-10 can be used in both skin and hair care products, however, it is primarily used in hair care products because of its anti-static, film forming, and moisturizing properties.

As an anti-static agent, polyquaternium-10 can be used for decreasing or eliminating static-charge buildup and fly-away hair. In addition, polyquaternium-10 functions as a film forming agent. The positive charge of this polymer enables it to readily adhere to hair, which is negatively charged. Polyquaternium-10 forms a soft film that provides a nice sheen. While this ingredient can be used as a hair fixative, its soft hold means that it is more susceptible to not retaining the style or curl. Polyquaternium-10 is better suited for use in shampoos and conditioners since it provides conditioning and shine, as well as improves wet combing and detangling.