Scotchgard

Scotchgard is a 3M brand of stain repellent and durable water repellent that is applied to fabrics, upholstery and carpets so that spills and dirt do not soak in. Its products are typically built on organofluorine chemicals carried in a petroleum distillate solvent. The coating was discovered by accident in 1953, when 3M laboratory technician Joan Mullan spilled a few drops of a fluorochemical liquid meant for rubber jet fuel hoses onto her tennis shoes and found that the treated spot resisted every ordinary cleaning method. 3M chemists Patsy Sherman and Samuel Smith then developed it into a treatment for most fabrics. Sales began in 1956 and a patent for the formula followed in 1973. Since 2003 the original PFOS ingredient has been replaced, and 3M now describes a proprietary fluorinated urethane.