You've been lied to this whole time.
Dry cleaning is not really dry at all.
It just isn't water wet. In the 1855s Jean Baptiste Jolly, an industrial dyer, noticed that his table cloth became cleaner after his made spilled a kerosene lamp on it. The use of petroleum based cleaners continued until enough cleaning facilities had exploded that after WWI cholorine based cleaners were being used. By the mid-1930s, perchloroethylene, commonly called "perc," became the standard solvent. It had the advantage of not occasionally erupting into deadly and costly fires. The down side was that it was the first substance to be classified as a carcinogen by the Consumer Product Safety Commission. While it is still in use, other methods have growing popularity.
Some of the cooler new methods (but not the only, at all):
- Liquid carbon dioxide--it doesn't explode and isn't going to give you cancer. However, it may heat up the atmosphere a little...The machines are 90k more than conventional ones because of the high pressure they need to keep the gas out so that it doesn't turn into a gas.
- Liquid silicone (decamethylcyclopentasiloxane) - twice as expensive as the traditional perc, but it breaks down into silica, water and carbon dioxide.
- More: http://en.wikipedia.org/wiki/Dry_cleaning#Solvents_used
Many dry cleaning machines use huge quantities of solvents--as much as 200 gallons. Since the washing machines also function as dryers they reclaim, re-condense, filter and recycle as much as 99.99% of the solvent.