A match is a small stick of wood or strip of cardboard with a
solidified mixture of flammable chemicals deposited on one end. When
that end is struck on a rough surface, the friction generates enough
heat to ignite the chemicals and produce a small flame. Some matches,
called strike-anywhere matches, may be ignited by striking them on any
rough surface. Other matches, called safety matches, will ignite only
when they are struck on a special rough surface containing certain
chemicals.
Raw Materials:
Woods used to make matchsticks must be porous enough to absorb various chemicals, and rigid enough to withstand the bending forces encountered when the match is struck. They should also be straight-grained and easy to work, so that they may be readily cut into sticks. White pine and aspen are two common woods used for this purpose.
Once the matchsticks are formed, they are soaked in ammonium phosphate, which is a fire retardant. This prevents the stick from smoldering after the match has gone out. During manufacture, the striking ends of the matchsticks are dipped in hot paraffin wax. This provides a small amount of fuel to transfer the flame from the burning chemicals on the tip to the matchstick itself. Once the paraffin burns off, the ammonium phosphate in the matchstick prevents any further combustion.
The heads of strike-anywhere matches are composed of two parts, the tip and the base. The tip contains a mixture of phosphorus sesquisulfide and potassium chlorate. Phosphorus sesquisulfide is a highly reactive, non-toxic chemical used in place of white phosphorus. It is easily ignited by the heat of friction against a rough surface. The potassium chlorate supplies the oxygen needed for combustion. The tip also contains powdered glass and other inert filler material to increase the friction and control the burning rate. Animal glue is used to bind the chemicals together, and a small amount of zinc oxide may be added to the tip to give it a whitish color. The base contains many of the same materials as the tip, but has a smaller amount of phosphorus sesquisulfide. It also contains sulfur, rosin, and a small amount of paraffin wax to sustain combustion. A water-soluble dye may be added to give the base a color such as red or blue.
The heads of safety matches are composed of a single part. They contain antimony trisulfide, potassium chlorate, sulfur, powdered glass, inert fillers, and animal glue. They may also include a water-soluble dye. Antimony trisulfide cannot be ignited by the heat of friction, even in the presence of an oxidizing agent like potassium chlorate, and it requires another source of ignition to start the combustion. That source of ignition comes from the striking surface, which is deposited on the side of the matchbox or on the back cover of the matchbook. The striking surface contains red phosphorus, powdered glass, and an adhesive such as gum arabic or urea formaldehyde. When a safety match is rubbed against the striking surface, the friction generates enough heat to convert a trace of the red phosphorus into white phosphorus. This immediately reacts with the potassium chlorate in the match head to produce enough heat to ignite the antimony trisulfide and start the combustion.
Match boxes and match books are made from cardboard. The finned strips of cardboard used to make the matches in match books are called a comb.
Woods used to make matchsticks must be porous enough to absorb various chemicals, and rigid enough to withstand the bending forces encountered when the match is struck. They should also be straight-grained and easy to work, so that they may be readily cut into sticks. White pine and aspen are two common woods used for this purpose.
Once the matchsticks are formed, they are soaked in ammonium phosphate, which is a fire retardant. This prevents the stick from smoldering after the match has gone out. During manufacture, the striking ends of the matchsticks are dipped in hot paraffin wax. This provides a small amount of fuel to transfer the flame from the burning chemicals on the tip to the matchstick itself. Once the paraffin burns off, the ammonium phosphate in the matchstick prevents any further combustion.
The heads of strike-anywhere matches are composed of two parts, the tip and the base. The tip contains a mixture of phosphorus sesquisulfide and potassium chlorate. Phosphorus sesquisulfide is a highly reactive, non-toxic chemical used in place of white phosphorus. It is easily ignited by the heat of friction against a rough surface. The potassium chlorate supplies the oxygen needed for combustion. The tip also contains powdered glass and other inert filler material to increase the friction and control the burning rate. Animal glue is used to bind the chemicals together, and a small amount of zinc oxide may be added to the tip to give it a whitish color. The base contains many of the same materials as the tip, but has a smaller amount of phosphorus sesquisulfide. It also contains sulfur, rosin, and a small amount of paraffin wax to sustain combustion. A water-soluble dye may be added to give the base a color such as red or blue.
The heads of safety matches are composed of a single part. They contain antimony trisulfide, potassium chlorate, sulfur, powdered glass, inert fillers, and animal glue. They may also include a water-soluble dye. Antimony trisulfide cannot be ignited by the heat of friction, even in the presence of an oxidizing agent like potassium chlorate, and it requires another source of ignition to start the combustion. That source of ignition comes from the striking surface, which is deposited on the side of the matchbox or on the back cover of the matchbook. The striking surface contains red phosphorus, powdered glass, and an adhesive such as gum arabic or urea formaldehyde. When a safety match is rubbed against the striking surface, the friction generates enough heat to convert a trace of the red phosphorus into white phosphorus. This immediately reacts with the potassium chlorate in the match head to produce enough heat to ignite the antimony trisulfide and start the combustion.
Match boxes and match books are made from cardboard. The finned strips of cardboard used to make the matches in match books are called a comb.
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