Rainbow Crafts (since 1956)
Hasbro (since 1991)
Play-Doh is a modeling compound used by young children for art and craft projects at home and in school. Composed of flour, water, salt, boric acid, and mineral oil, the product was first manufactured in Cincinnati, Ohio, U.S., as a wallpaper cleaner in the 1930s. When a classroom of children began using the wallpaper cleaner as a modeling compound, the product was reworked and marketed to Cincinnati schools in the mid-1950s. Play-Doh was demonstrated at an educational convention in 1956 and prominent department stores opened retail accounts. Advertisements promoting Play-Doh on influential children's television shows in 1957 furthered the product's sales. Since its launch on the toy market in the mid-1950s, Play-Doh has generated a considerable amount of ancillary merchandise such as The Fun Factory. In 2003, the Toy Industry Association named Play-Doh in its "Century of Toys List".
The non-toxic, non-staining, reusable modeling compound that came to be known as "Play-Doh" was originally a pliable, putty-like substance concocted by Noah McVicker of Cincinnati-based soap manufacturer Kutol Products; it was devised at the request of Krogers Grocery, which wanted a product that could clean coal residue from wallpaper. Following World War II, with the transition from coal-based home heating to natural gas and the resulting decrease in internal soot, and the introduction of washable vinyl-based wallpaper, the market for wallpaper cleaning putty decreased substantially. McVicker's nephew, Joseph McVicker, joined Kutol with the remit to save the company from bankruptcy; he subsequently discovered that the wallpaper cleaner was being used by nursery school children to make Christmas ornaments.
Joe McVicker took Play-Doh to an educational convention for manufacturers of school supplies, and Woodward & Lothrop, a department store in Washington, DC began selling the compound. In 1956, the McVickers formed the Rainbow Crafts Company to make and sell Play-Doh. Also in 1956, a three-pack of 7-ounce cans was added to the product line, and, after in-store demonstrations, Macy's of New York and Marshall Field's of Chicago opened retail accounts. In 1957, chemist Dr. Tien Liu reduced Play Doh's salt content (thus allowing models to dry without losing their color), and Play-Doh ads were telecast on Captain Kangaroo, Ding Dong School, and Romper Room. In 1958, Play-Doh's sales reached nearly $3 million.
In 1964, Play-Doh was exported to Britain, France, and Italy. In the 1980s, its cardboard can (with a rust-prone metal bottom) was scuttled for a more cost effective plastic container. By 1965, Rainbow Crafts was issued a patent for Play-Doh. Also in 1965, General Mills purchased Rainbow Crafts and all rights to Play-Doh for $3 million, placing the compound with its Kenner Products subsidiary. In 1971, Rainbow Crafts and Kenner Products merged, and, in 1987, the Tonka Corporation bought the two. In 1991, Hasbro became Play-Doh's owner, and continues to manufacture the product today through its Playskool division. In 1996, gold and silver were added to Play-Doh's palette to celebrate its 40th anniversary.
Play-Doh packaging was briefly illustrated with children in the mid-1950s, but replaced by an elf mascot which, in 1960, was superseded by Play-Doh Pete, a smock and beret-wearing cartoonish boy. In 2002, Play-Doh Pete's beret was replaced with a baseball cap.Since then, living Play-Doh cans are seen on commercials and a new mascot called Tubby was seen as a meet-and-greet at the 2012 Toy Fair.
Play-Doh's current manufacturer, Hasbro, reveals the compound is primarily a mixture of water, salt, and flour, while its 2004 United States patent indicates it is composed of water, a starch-based binder, a retrogradation inhibitor, salt, lubricant, surfactant, preservative, hardener, humectant, fragrance, and color. A petroleum additive gives the compound a smooth feel, and borax prevents mold from developing. Many home-made recipes will include a vegetable, canola, or olive oil and cream of tartar as well.
In 1960, the Play-Doh Fun Factory (a toy press that extrudes the compound in various shapes) was invented by Bob Boggild and Bill Dale. The Play-Doh Fuzzy Pumper Barber & Beauty Shop of 1977 featured a figurine whose extruded "hair" could be styled. Making its debut in 1996 for computer-savvy young modelers was an educational software CD-ROM game, Play-Doh Creations, and, in 2003, the Play-Doh Creativity Table was made available. Play-Doh related merchandise introduced during the 2007 anniversary year included the Play-Doh Birthday Bucket, the Play-Doh Fifty Colors Pack, the Fuzzy Pumper Crazy Cuts (a reworking of the 1977 Fuzzy Pumper Barber & Beauty Shop), and the Play-Doh Creativity Center.
More than two billion cans of Play-Doh were sold between 1955 and 2005, and, in 2005, Play-doh was being sold in 75 countries around the world at 95 million cans a year. In the United States, more than 6,000 stores carry Play-Doh. 
To mark Play-Doh's fiftieth anniversary, Demeter Fragrance Library created a limited-edition fragrance inspired by Play-Doh's odor for "highly-creative people, who seek a whimsical scent reminiscent of their childhood."
In the 2010 romantic-comedy movie How Do You Know finale, Paul Rudd's character tells the story of Play-Doh to Reese Witherspoon's character, saying: "I have kept this for a long time as proof that we're all just one small adjustment away from making our lives work."   
- Walsh, Tim (2005). "Play-doh". Timeless Toys: Classic Toys and the Playmakers Who Created Them. Kansas City: Andrews McMeel Publishing. pp. 115–120. ISBN 978-0-7407-5571-2.
- Wilson, Tracy V. "How Play-Doh Modeling Compound Works". How Stuff Works. Retrieved 19 February 2009.
- Sobey, Edwin J.C.; Woody Sobey (2008). The Way Toys Work: The Science Behind the Magic 8 Ball, Etch A Sketch, Boomerang, and More. Chicago Review Press. p. 96. ISBN 978-1-55652-745-6.
- "Toy Industry Association Announces Its Century of Toys List". Business Wire. 21 January 2003. Archived from the original on 9 February 2009. Retrieved 19 February 2009.
- "Accidental Brands", from Under the Influence, by Terry O'Reilly, on CBC.ca; first broadcast March 17, 2012
- "Rainbow Crafts Company, Inc.". Ohio History Central. 28 July 2006. Retrieved 30 October 2008.
- Phil Ament. "Play-Doh History - Invention of Play-Doh". Ideafinder.com. Retrieved 2011-05-23.
- "The 50 Year History of Play-Doh". 2006. Retrieved 19 February 2009.
- Noah W. McVicker and Joseph S. McVicker, "Plastic modeling composition of a soft, pliable working consistency," U.S. patent no. 3,167,440 (filed: May 17, 1960; issued: January 26, 1965).
- "Patent Storm". Retrieved 19 February 2009.
- How to Make Playdough, How to Make Playdough Dot Net