Tetrachloroethylene, also known under the systematic name tetrachloroethene, or perchloroethylene ("perc" or "PERC"), and many other names, is a chlorocarbon with the formula Cl2C=CCl2. It is a colorless liquid widely used for dry cleaning of fabrics, hence it is sometimes called "dry-cleaning fluid". It has a sweet odor detectable by most people at a concentration of 1 part per million (1 ppm).
It is used as a alternative to chlorofluorocarbon (CFC) refrigerants.
It is also used in the synthesis of hydrochlorofluorocarbons (HCFCs) 123 and 124 and HFC 125.
Perchloroethylene is also an important solvent in dry cleaning industries. It is used in aerosol formulations for the automotive aftermarket, particularly for brake cleaning.