Dry cleaning is any cleaning process for clothing and textiles using a solvent other than water. Clothes are instead soaked in a water-free liquid organic solvent typically inside a specialised dry-cleaning machine. The most commonly used solvent is Perchloroethylene, although other solvents such as hydrocarbon mixtures and decamethylcyclopentasiloxane are also used. Historical solvents include carbon tetrachloride, trichloroethylene, trichlorotrifluoroethane, trichloroethane and n-propyl bromide.
Read more on Wikipedia