Fabric softener

A fabric softener (recently called fabric conditioner by some producers for marketing purposes) is a chemical compound that is typically applied to laundry during the rinse cycle in a washing machine. Fabric softeners are available as solutions and solids, and may also be impregnated in dryer sheets used in a clothes dryer.

Many modern washing machines have a dispenser that adds liquid fabric softener automatically on the final rinse. Users of launderette machines may need to add it manually. Some washing powder brands have fabric conditioning mixed in, which manufactures claim saves money compared to buying separate washing powder and fabric softener. Some manufacturers claim their products make ironing easier or make clothes dry faster. All liquid fabric softeners are added to water—either by adding the product directly to the final rinse water or by 2:1 (water:softener) dilution in an automatic dispenser. Even diluted fabric softener can cause spotting when poured directly onto clothes, and can ruin them.

Dry fabric softeners are typically supplied in the form of dryer sheets added in the clothes dryer to soften the fabric and prevent buildup of static electricity in susceptible fabrics. Many users advocate alternative uses of dryer sheets, such as dusting, and removing hair from clothes.

Fabric softeners coat the surface of a fabric with chemical compounds that are electrically charged, causing threads to "stand up" from the surface so the fabric feels softer and makes it fluffier. Cationic softeners bind by electrostatic attraction to the negatively charged groups on the surface of the fibers and neutralize their charge. The long aliphatic chains then line up towards the outside of the fiber, imparting lubricity.

Electrically conductive fabric softener chemicals may also prevent static charge buildup in clothes dryers. Other functions manufacturers claim include less friction during ironing, increased stain resistance, reduced wrinkling and pilling, and lower drying time. Most contain fragrances. Cationic fabric softeners are added during the rinse cycle rather than the wash cycle because they can interfere with detergent cleaning action. In addition to fabric softening chemicals, fabric softeners may include acids or bases to maintain optimal pH for absorption, silicone-based anti-foaming agents, emulsion stabilizers, fragrances, and colors.

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