Scotchgard is a combination of the words Scotch, meaning Scotsman, and a misspelling of guard, meaning to protect.
In 1902, 3M was started by five businessmen in Two Harbors, Minnesota, to sell corundum to manufacturers for grinding wheels. When that failed, the company moved to Duluth and converted an old flour mill to a sandpaper factory, eventually moving to St. Paul in 1910. The company introduced Scotch brand masking tape in 1925, followed by Scotch brand cellophane tape in 1930.
In 1944, 3M bought the rights to a process for producing fluorochemical compounds. 3M researchers could not find any practical uses for the process or its reactive, fluorine-containing byproducts—until a laboratory assistant accidentally spilled a sample of the substance on her tennis shoes. The assistant could not wash the stuff off with water or hydrocarbon solvents, and the stained spot on her tennis shoe also resisted soiling. 3M chemists Patsy Sherman and Sam Smith realized this substance might be used to make textiles resist water and oil stains and went to work to enhance the compound's ability to repel liquids, giving birth to Scotchgard.
Dr. Richard Smith, the son of Sam Smith, led a team of scientists working to eliminate the ozone-depleting chemical methyl chloroform in the product his father developed. In 1994, 3M introduced the new water-based Scotchgard.
3M voluntarily phased out most uses of chlorofluorocarbons (CFCs) and other Class I ozone-depleting chemicals at its operations worldwide by the end of 1992, four years before the United States government mandate for 1996.
In 1977, there were nearly thirty formula variations for Scotchgard for protecting materials including furniture fabrics, wall coverings, luggage, and carpets.