Static electricity is a part of nature that makes all sorts of cool things to happen. It allows laser printers to work. It helps balloons stick to walls after rubbing them through your hair. And it can also cause lightning. But sometimes, static electricity is not that cool. When static electric charges build up on your clothes, they can result in something called static cling. When this happens, your clothes get stuck together. They’ll also stick to you! This is one reason why people use fabric softeners in their dryers.
Did You Know? A bolt of lightning is just like the spark you get after rubbing your socks on carpet, only millions of times bigger!!
There are four conditions that cause a static electric charge to build up:
- a dry environment;
- two surfaces made of different materials;
- two surfaces are brought together and then separated;
- both materials are poor conductors of electricity.
The clothes bumping around in your dryer satisfy most of these conditions. That’s why your dryer often causes that dreaded static cling!
How does your dryer cause static cling?
By the end of the dryer cycle, most of the humidity has been removed from your clothes, and the air inside the dryer is dry (condition #1). The different clothing items in the dryer are made of different materials (#2). Finally, the clothes are constantly rubbing against each other (#3).
As a result, when your sock comes into contact with your sweater in the dryer, they create friction. The friction causes electrons from one of the items to move to the other item. The item that lost electrons becomes positively charged. The item that gained the electrons becomes negatively charged. Two materials that have an opposite charge will attract, or “cling” to each other.
So how do fabric softeners stop static cling?
When you add a liquid fabric softener to the wash, or a dryer sheet to the dryer, your clothes become coated with a very thin layer of chemicals. These chemicals are called surfactants. They reduce the surface friction of the clothing fibres. So when the clothes are tumbling in the dryer, it is actually the chemicals coating the clothes that are touching each other. Because the chemicals on the pieces of clothing are the same, there is less friction and electrons don’t rub off as easily (remember condition #3?). This helps prevent the transfer of electrons, which stops the items from becoming oppositely charged. No opposite charges means no static cling!
Fabric softeners do a great job of stopping static cling, but there are some drawbacks. The chemicals in these products can be toxic, or cause allergic reactions in some people. They also stay on your clothes.
How else can you stop static cling?
You can also stop static cling with some simple physics. Since metals are good conductors of electricity, electrons will quickly move from a non-metal surface to a metal. You can run a metal hanger over your clothes before you wear them. If your skin is really dry, a static charge might build up as the clothes rub over your body as you put them on. This can also happen when the air is really dry, like it can be in the winter. If your clothes cling to your body after you put them on, run the hanger over the clothes again. You can also use a skin moisturizer to reduce the friction between your clothes and your skin so charges will not build up.
If you decide to use a fabric softener, read the label carefully in case you are sensitive or allergic to any of the ingredients. Then, decide whether if it’s worth it to avoid a little static cling.
MadSci network: How does the anti-static sheet I throw in with the laundry work?
TLC:How Stuff Works
eHow:How Does a Dryer Sheet Reduce Static Cling?
School for Champions: Basics of Static Electricity
Article first published on October 18, 2010.
This article was updated by Let's Talk Science staff in collaboration with the author on 2017-03-17 to improve readability.