How Dryer Sheets Work

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Dryer sheets have a special technology that helps to soften clothes and prevent static cling directly from the dryer.
Peter Cade/Getty Images

Have you ever experienced a situation where you thought you lost a sock in the dryer, but it stubbornly clung to the arm of your sweater? Or did you ever take a freshly cleaned shirt out of the dryer, only to feel a stiff texture instead of the expected warm softness? Simply running a load of clothes through the wash and dry cycles does not always produce the desired results.

The root cause of these problems is not necessarily due to the quality of the clothing or because something went wrong in the laundry process. Instead, they are usually side effects of wet washing and the automated drying cycle. When clothes tumble together in the dryer, they can become stuck together due to static electricity. However, fabric softeners, specifically dryer sheets, can help prevent this from happening.

Fabric softeners were invented in the mid-20th century to make clean clothes more pleasant to touch. Later, chemicals were added to help prevent static. However, using softeners was not very convenient. They had to be added after the first wash cycle in an automatic washer because softeners were cationic, with a positive electrical charge, and detergents were anionic, or negatively charged [source: Toedt et al]. Combining the two caused them to counteract, reducing the effectiveness of both.

A scientist named Conrad J. Gaiser is believed to have made the second breakthrough in the 1960s by figuring out how to treat small sheets of material with fabric softener. When the sheets were put in the dryer with the laundry, the heat and moisture warmed up the softener and spread it across the clothing. Although washing machine manufacturers later added an automatic fabric softener dispenser, dryer sheets remain popular. They are used not only for laundry but also for many off-label purposes, such as cleaning and keeping insects and rodents away.

There are many brands of dryer sheets, but they all solve some of the same problems. In the next section, we explain what exactly happens inside the dryer to cause static cling.

Static and Fabric Softening


The static electricity caused by clothes tossing in the dryer is much like the one that causes a shock when you touch a doorknob.
ŠiStockphoto.com/David Elfstrom

When most people think of dryer sheets, the first thing that comes to mind is static electricity. Dryer sheets are supposed to prevent clothes from producing static electricity. If you don’t use one, you might have to peel your clothes apart as if they were glued together. The reason for this is similar to the shock you get when you shuffle your feet across a carpet on a dry winter day and then reach for a doorknob.

In both cases, static charge builds up as a result of two different materials rubbing against each other. The rubbing can knock loose electrons, the outer, orbiting, negatively charged parts of an atom, from some fabrics onto others. So your sweater, for example, might end up with too many electrons and a negative charge, while your sock might have too few electrons and a positive charge. Opposites attract in electricity, which is why the sock might seem to have suddenly attached itself to the sweater.

When materials such as cotton or wool receive a static charge, it can take some time for the charge to dissipate. This is why when your finger gets close to a doorknob, you feel a shock – your body’s static charge is rapidly dispersed through the highly conductive doorknob. However, clothing made of non-conductive materials like socks and sweaters can’t easily dissipate static charges, which is why they tend to hold onto them longer. On humid or damp days, static is less of a problem because water is an excellent conductor and quickly disperses any charge. Alternatively, dryer sheets can be used to prevent static in dry clothes by balancing electrons with positively charged ions. While there are many different types of dryer sheets on the market, they all contain nonwoven polyester squares designed to eliminate static and make clothes softer. They also typically have a fragrant scent and contain a surfactant that heats up during the drying cycle to coat clothes with a fatty substance and positively charged atoms. However, the specific chemicals used in dryer sheets are not always listed on the packaging.

The use of dryer sheets has been criticized by safety advocates due to the potential danger of ingesting or inhaling chemicals used by some manufacturers. A study conducted in 2007 revealed that all six scented laundry products and air fresheners tested contained harmful chemicals that were not listed on the label. Although only one of the products was a dryer sheet, it emitted two toxic chemicals – ethanol and alpha-pinene. While the amounts of chemicals used on dryer sheets are small, many people prefer not to use them, especially on children’s clothes. If you’re looking for healthier or cheaper alternatives to standard dryer sheets, there are various options available, including reusable sheets, fabric softeners, dryer balls, and gentler detergents. Some people use white vinegar during the rinse cycle to soften clothes and get rid of mildew. However, it’s important to remember that dryer sheets offer three main advantages – eliminating static, softening clothes, and adding a fragrance. Different alternatives may not provide all three benefits.

On the Line

If you prefer not to use dryer sheets but still want your laundry to have a pleasant scent, try adding a few drops of lavender or any essential oil of your choice during the washer’s spin cycle or as you toss the clothes into the dryer. However, be careful because some oils can cause skin irritation.

Alternative Uses for Dryer Sheets


As one of their numerous off-label uses, some people use dryer sheets to remove dust.
ŠiStockphoto.com/Dmitriy Yakovlev

If you search online for dryer sheets, you will discover how popular they are for off-label purposes. People have found countless ways to repurpose dryer sheets, such as scrubbing counters and removing dust. Most of these unconventional uses are related to the main functions of dryer sheets, which include reducing static, chemically softening clothes, and producing a pleasant scent. Here are a few examples:

  • Static related — Dryer sheets have become trendy for rubbing against dust-prone surfaces such as window blinds. The sheets apply a positive electrical charge that repels dust particles, preventing them from settling. This applies to any surface with dust; a dryer sheet in a vacuum bag, for example, can prevent dust from clogging the tubes.
  • Cleaning and scrubbing — Some of the chemicals used for fabric softening and fragrance on dryer sheets can help with cleaning. Try using a dryer sheet to scrub dead bugs off your car or throw one in with any paintbrushes you’re cleaning — some dryer sheets may contain acetone, which is also found in paint thinners.
  • Scent and fragrance — Although you might find dryer sheets pleasant, household pests do not. Ants, bees, and mice have been known to avoid dryer sheets. You can also place dryer sheets in musty areas, such as old shoes or closets, to improve their odor.

You will find a plethora of other off-label uses, and you might even come up with some of your own. Just keep in mind that dryer sheets are not suitable for every purpose, such as removing loose fur from your pet cat or dog. Although this technique is sometimes used for removing lint, it is not recommended for pets because it could leave behind chemicals that could be ingested and cause harm.

Learn more about the science behind dryer sheets and fabric softening by clicking on the links on the following page.

Originally Published: Nov 30, 2009

Frequently Asked Questions About Dryer Sheets

Dryer sheets are small squares of fibers coated with fatty acids, scents, and various chemicals that melt in the dryer and coat clothes to make them soft and reduce static electricity. While they have obvious benefits, you don’t have to use dryer sheets and can opt for alternatives such as baking soda, wool dryer balls, and foil balls. Some people claim that the chemicals in dryer sheets, such as benzyl alcohol, benzyl acetate, and ethanol, are harmful to humans, but they are generally recognized as safe by the FDA. However, dryer sheets are flammable and can start a fire.

More Information

Related HowStuffWorks Articles

  • How Dry Cleaning Works
  • How can you wash and dry your clothes with steam?
  • 10 Green Laundry Tips

More Great Links

  • 25 Alternative Uses for Fabric-Softener Dryer Sheets
  • Bounce Favorite Stories
  • The Toxic Danger of Fabric Softener and Dryer Sheets

Sources

  • American Conference of Governmental Hygienists. “Selected Chemicals Which Pose a Skin Absorption Hazard.” North Carolina State University. 2005. (Accessed Oct. 27, 2009) http://www.ncsu.edu/ehs/www99/right/handsMan/lab/skin%20absorption.pdf
  • Beaty, William J. “What IS Static Electricity?” Science Hobbyist. 2005. (Accessed Oct. 20, 2009) http://amasci.com/static/what_is_static.html
  • Gavigan, Christopher. “5 Secrets Conventional Cleaning Product Manufacturers Don’t Want You to Know.” The Huffington Post. April 29, 2009. (Accessed Nov. 18, 2009)http://www.huffingtonpost.com/christopher-gavigan/5-secrets-conventional-cl_b_191845.html
  • Hickey, Hannah. “Toxic chemicals found in common scented laundry products, air fresheners.” University of Washington News. 7/23/2008. (Accessed Oct. 20, 2009)http://uwnews.org/article.asp?articleID=42872
  • Kendall, Julie. “Health Risks from Perfume: The Most Common Chemicals Found in Thirty-One Fragrance Products by a 1991 EPA Study.” Immune Web. 1995. (Accessed Oct. 20, 2009) http://www.immuneweb.org/articles/perfume.html
  • Kozen, Frances. “Liquid surfactant on dryer sheets coats fabric, eliminating cling.” Cornell University — Ask a Scientist. Feb. 8, 2006. (Accessed Nov. 18, 2009)http://www.ccmr.cornell.edu/education/ask/index.html?quid=1078
  • Krasicky, John. “Dry air makes static electricity more noticeable in the winter.” Cornell University — Ask a Scientist. Jan. 22, 2004. (Accessed Nov. 17, 2009)http://www.ccmr.cornell.edu/education/ask/index.html?quid=464
  • Main, Emily. “Virtuous Cycles: Laundry Detergents.” National Geographic Green Guide. 4/30/2007. (Accessed Oct. 20, 2009)http://www.thegreenguide.com/home-garden/cleaning/laundry-detergents
  • Steinemann, Anne C. “Fragranced consumer products and undisclosed ingredients.” Environmental Impact Assessment Review. July 23, 2008. (Accessed Nov. 18, 2009)http://www.national-toxic-encephalopathy-foundation.org/undisclosed.pdf
  • Toedt, John; Darrell Koza; and Kathleen Van Cleef-Toedt. “Chemical composition of everyday products.” Greenwood Press, Westport, Conn.: 2005. (Accessed Nov. 18, 2009)http://books.google.com/books?id=UnjD4aBm9ZcC&pg=PA22&dq=fabric+softener+ionic#v=onepage&q=&f=fale
  • Wang, Linda. “Dryer Sheets.” Chemical & Engineering News. 4/14/2008. (Accessed Oct. 20, 2009)http://pubs.acs.org/cen/whatstuff/86/8615sci2.html

FAQ

1. What are dryer sheets?

Dryer sheets are small, thin sheets made of polyester or cellulose material that are coated with fabric softener and a variety of other ingredients. They are used in the dryer to reduce static cling, soften clothes, and add a pleasant scent to laundry.

2. How do dryer sheets reduce static cling?

Dryer sheets contain positively charged ingredients that neutralize the negatively charged electrons on clothing, which causes static cling. When the dryer sheet is heated in the dryer, these ingredients transfer to the clothes, leaving them with an invisible coating that prevents static buildup.

3. Can dryer sheets be reused?

While it may be tempting to use the same dryer sheet multiple times, it is not recommended. The ingredients on the sheet are designed to be used only once, and reusing the sheet can result in decreased effectiveness and even damage to the dryer.

4. Are dryer sheets safe to use?

Most dryer sheets on the market are safe to use, but it is important to follow the manufacturer’s instructions for proper usage. Some people may have sensitive skin and experience irritation from the ingredients in the dryer sheet, so it is best to test a small area of clothing before using the sheet on a full load.

5. Can dryer sheets be used in all types of dryers?

Dryer sheets can be used in most types of dryers, including gas and electric dryers. However, they should not be used in dryers that use steam, as the steam can reduce the effectiveness of the dryer sheet.

6. Do dryer sheets have any environmental impact?

Some dryer sheets contain chemicals that can have a negative impact on the environment, such as synthetic fragrances and petrochemicals. However, there are eco-friendly dryer sheet options available that use natural ingredients and are biodegradable.

7. Are dryer sheets necessary?

Dryer sheets are not necessary for drying clothes, but they can provide benefits such as reducing static cling and adding a pleasant scent to laundry. Ultimately, whether or not to use dryer sheets is a personal preference.

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