Quats

The term "quats" is an acronym for "quaternary ammonium compounds", erroneously also called quaternary ammonium compounds (lat. quaternarius = consisting of four each). Quaternary ammonium compounds are organic ammonium compounds in which all 4 valences of a nitrogen atom are organically bound. They are therefore salts (ionic compounds), consisting of a cation and an anion.

Quaternary ammonium compounds are widely used in cosmetic formulations. They act as antistatic agents, hair conditioning agents and preservatives in hair care products - see also quaternium and polyquaternium.