How Do Dry Cleaning Products Work?

• Dry Cleaning

  Some fabrics don't do well with water or soap, so they need to be dry cleaned. However, dry cleaning isn't really "dry," it's just water-free; the cleaning is still done with a liquid chemical solvent. The standard dry-cleaning fluid these days is Perchloroethylene, a petroleum-based product called "perc" for short by dry-cleaning professionals. After you drop your dry cleaning off, the pockets are checked for items like pens that could ruin your clothes. Then tough stains are treated by hand before your garments are placed in a large dry-cleaning machine with similar colors. The dry-cleaning fluid, and sometimes detergent and a small amount of water, fill the drum about 1/3 of the way. The machine agitates the clothing at a constant temperature of 30 degrees Celsius; anything higher could damage the solvent. After cleaning, the liquid is removed and a fresh batch of clean solvent rinses the load. Then that fluid is drained through fast spinning, and your clothes are dried by being tumbled in warm air, usually right in the same machine. Next, cool air deodorizes the clothes and removes most traces of solvent. Finally, they're checked for lingering stains that need another treatment, then pressed, shaped, hung on hangers and covered with plastic. The same solvent is used for several loads; it gets recycled through a filtering or distilling process after each cleaning to remove the detergent, dirt and oil. When it can't be reused any more, perc is disposed of as hazardous waste. Most often it's recycled or incinerated at a special facility.

• Home Dry Cleaning

  You can now purchase home dry-cleaning products, such as Dryel, that work in your dryer. Like commercial dry cleaning, you treat any stains with a liquid solvent first, and then tumble your clothes with more fluid, except that it's contained in a wet sheet. And rather than really cleaning them, the sheets refresh your clothes with a perfume and remove wrinkles by creating steam. This process won't work for leather, suede or velvet, but the good news is that it's cheaper than commercial dry cleaning and safer for the environment.

• History

  Dry cleaning was discovered by accident. In the mid-19th century, a French dye-works owner named Jean Baptiste Jolly noticed something strange: after his maid had spilled kerosene on his table cloth, it ended up cleaner. So the earliest petroleum solvents were actually kerosene and gasoline, which are obviously very flammable. As a result, there were many fires and explosions, so the government started to regulate dry cleaning. After World War I, chlorinated solvents started replacing petroleum ones, and by the 1930s perc became the standard -- a substance containing both chlorine and petroleum.

• Alternatives to Dangerous Solvents

  Recently, perc was banned in California because it's a carcinogen with numerous potential health risks for people who are in contact with it, including liver, kidney and neurological damage. The biggest danger is to professionals who work with it daily, but it can also be hazardous for dry-cleaning customers. You can minimize your exposure to the toxins by removing the plastic wrap from your clothes as soon as you get them home, and letting them air out completely. Many dry cleaners are now moving to perc-free carbon dioxide-based solvents. Others also offer wet cleaning for a variety of fabrics; yes, we're back to basically talking about the standard washing machine process again, except that professional cleaners have special gentle machines with fewer washing rotations and a more effective spin cycle, so they can do it without shrinking or ruining your delicate fabrics, even leather. Now, when you take your clothes to be dry cleaned, they may actually be wet cleaned instead.

References & Resources

• Dry Cleaning At Home
• Eco-Friendlier Dry Cleaning
• Wet Cleaning