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Why does dry cleaning turn clothes dingy gray?
If you are a frequent dry cleaning customer, you may have noticed that sometimes your lighter colored garments come back dingy or grayish in color after dry cleaning. This problem is most often caused by a process called “redeposition”.
The cause of redeposition is very similar to what happens to bath water when you take a bath, you become cleaner and the water becomes dirtier. When clothes are dry cleaned, the dirt, oil, and grime on the dirty clothes is removed and then becomes suspended in the dry cleaning solvent. Redeposition occurs when the suspended soil is “re-deposited” onto garments in subsequent loads. There is often a faint but very unpleasant odor associated with redeposition. It smells like a cross between body odor, stinky feet, and rotting fish.
Dry cleaning solvent is very expensive, so its typically filtered, distilled, recycled, and reused many times. Many higher quality dry cleaners avoid redeposition by continually distilling or “cooking” their solvent, so each load of clothes is cleaned with fresh solvent. However, continually distilling solvent is expensive. So, some cleaners (especially the one price, deep discount, economy cleaners) save money by waiting as long as possible before they distill their solvent. Fresh solvent should be clear, but I’ve seen some cleaners using solvent as dark as black coffee. It’s really gross!
There is some good news. The dingy gray color and foul odor caused by redeposition can often be removed by dry cleaning the garment in fresh solvent. When shopping for a new cleaner, ask them how often they distill their solvent. “Continually” is the best answer.