Plasticine, a brand of modelling clay, is a putty-like modelling material made from calcium salts, petroleum jelly and aliphatic acids. The name is a registered trademark of Humbrol but tends to be used as a generic description in the United Kingdom and the Commonwealth.
Plasticine was formulated by art teacher William Harbutt of Bathampton, near Bath, England in 1897. He wanted a non-drying clay for use by his sculpture students. Although the exact composition is a secret, Plasticine is composed of calcium salts (principally calcium carbonate), petroleum jelly, and long-chain aliphatic acids (principally stearic acid). It is non-toxic, sterile, soft, malleable, and does not dry on exposure to air (unlike superficially similar products such as Play-Doh, which is based on flour, salt and water). It cannot be hardened by firing; it melts when exposed to heat, and is flammable at much higher temperatures.
A patent was awarded in 1899, and in 1900 commercial production started at a factory in Bathampton. The original Plasticine was grey, but the product initially sold to the public came in four colours. It was soon available in a wide variety of bright colours. Plasticine was popular with children, widely used in schools for teaching art, and found a wide variety of other uses (moulding for plaster casts, for example). The Harbutt company promoted Plasticine as a children's toy by producing modelling kits in association with companies responsible for popular children's characters such as Noddy, the Mr Men and Paddington Bear.
The original Plasticine factory was destroyed by fire in 1963 and replaced by a modern building. The Harbutt company continued to produce Plasticine in Bathampton until 1983. It is still manufactured today, but in smaller quantities, and is marketed once more as an art material.
Plasticine is often used in animation. One of its main proponents is Nick Park, who used characters modeled in Plasticine in his Oscar-winning short films The Wrong Trousers (1992) and A Close Shave (1995). This technique is popularly known as claymation in the US, and is a form of stop motion animation. Plasticine is appealing to animators because it can be used with ease: it is moldable enough to create a character, flexible enough to allow that character to move in many ways, and dense enough that it can retain its shape easily when combined with a wire armature.
A similar product, "Kunst-Modellierton" (known as Plastilin), was invented by Franz Kolb of Munich, Germany in 1880. This product is still available, known as "Münchner Künstler Plastilin" (Munich artists' plasticine).