Match

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Match, short, thin piece of wood, cardboard, or waxed string, tipped with a mixture of fire-producing substances, and used to produce a flame. One of the first matches produced was the brimstone match, made by dipping thin strips of wood into melted sulfur; the sulfur points ignited when applied to a spark produced by a flint and steel. In 1812 a chemical match was invented. Coated with sulfur and tipped with a mixture of potassium chlorate and sugar, it ignited when touched to sulfuric acid.

Matches made with phosphorus and ignited by friction were invented in 1827 by the British chemist John Walker, and have been used in improved form ever since. In the modern friction match, one end of the bare stick is dipped in a fireproofing agent, so that it will not burn readily, and the other end is coated with paraffin. The head of the match contains an oxidizing agent, such as potassium chlorate; a substance that oxidizes readily, such as sulfur or rosin; a filler of clay; a binding material, such as glue; and dye to give it distinctive color. At the very tip is a small amount of phosphorus trisulfide, which decomposes and burns at a low temperature; this ignites the paraffin, which burns more readily because of the presence of the other chemicals.

Safety matches are so designed that the head can be ignited only by striking on the friction surface provided on the match package. The tip of the safety match contains antimony trisulfide and an oxidizing agent, which are held in place with casein or glue. The striking surface on the package contains powdered glass for friction, red phosphorus, and glue. When the match is struck, the heat of friction converts the red phosphorus to white phosphorus, which ignites and in turn ignites the head of the match.

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