Pig bristle was used for cheaper ones, and badger hair for the more expensive ones. The first patent for It was by H. N. Wadsworth in 1857 in the United States, but mass production in the USA only started in 1885. Animal bristle was not an ideal material as it retains bacteria and does not dry well, and the bristles often fell out. Natural animal bristles were replaced by synthetic fibers, usually nylon, by DuPont in 1938. The first nylon bristle was made with nylon yarn, went on sale on February 24, 1938. In January 2003 It was selected as the number one invention Americans could not live without according to the Lemelson-MIT Invention Index. What Product ?
A-Toothbrush
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