Patsy Sherman of Bloomington, a retired 3M chemist who co-invented Scotchgard when she was in her 20s, died Monday in Minneapolis.
Sherman, who suffered a stroke in December, was 77.
In 1953, Sherman and Samuel Smith focused on an accident in a 3M lab, after an experimental compound dripped on someone's canvas tennis shoes and couldn't be cleaned off.
Sherman and Smith started thinking about an idea that seemed impossible at the time, a fluorochemical polymer that could repel oil and water from fabrics, according to a Jan. 8, 2005, Star Tribune article.
In 1956, their joint research resulted in the first sales of a Scotchgard product, a stain repellent for wool.
Sherman continued to develop a line of Scotchgard products, and in 2001 she was inducted into the National Inventors Hall of Fame. She held more than a dozen patents.
Smith died in 2005.
Investigations on the effect of perfluorochemicals (PFCs), formerly used in Scotchgard and other products, on the environment and human health continue. It has turned up in water, animals and people around the world, and it doesn't break down easily.