Clairol is a personal care products division of Procter & Gamble. The Clairol company was started in 1931 by Lawrence M. Gelb and wife, Joan, who named their enterprise after a hair-coloring preparation they found while traveling in France. In the 1950s, after two decades of selling the company’s hair tint to beauty salons, Clairol became a household name when it launched the first one-step home hair color formula, Miss Clairol Hair Color Bath, which debuted with the now-famous catchphrase, “Does she…or doesn’t she? Only her hairdresser knows for sure.” Within six years of Miss Clairol’s launch, 70% of women were coloring their hair.

Info gleaned from Wikipedia.