A match is a small stick made of wood with a hardened mixture of flammable chemicals at one end. When it is rubbed against the side surface of the box, both contact surfaces are heated. Enough heat is generated to cause a small flame.
Wood requirements
The wood for making matches must be porous enough to absorb the necessary amount of chemicals, and flexible so as not to break when rubbing against boxes. However, it should be easy to handle. Aspen and white pine are best suited to these conditions.
In Russia, aspen grater safe matches are mainly produced. For their ignition, a box is to be coated with a special composition of chemicals.
Manufacturing process
First, billets are made of wood - sticks of a certain length and section. Next, the so-called straw is soaked in a solution of ammonium phosphate. This is done to prevent decay after the combustion of the incendiary head, which is called the head of the match. After drying and grinding, the workpieces are installed in the matrix of the transportation drum, with the help of which all subsequent operations of industrial production are performed.
The billets are heated and one end is dipped in paraffin. When ignited, it will provide a small additional amount of fuel for combustion, so that the flame that flares up during friction is sufficient to ignite a match. As soon as the paraffin vapor burns out, ammonium phosphate, which is impregnated with the straw, will prevent further combustion. An adhesive mixture of the chemical composition of the match head is applied on top.
Match matches
They ignite only when the head is rubbed against the side of the box specially designed for ignition. The composition of the chemicals has remained unchanged since the invention of the Swedish matches in 1855: sulfur, potassium chlorate (Bertolet's salt KClO 3 ), manganese oxide (pyrolusite) and fine glass powder.
These are the main components that provide combustion. Bertoletova salt is an oxidizing agent, an oxygen supplier, without which the flame will quickly go out. Pyrolusite is used to slightly reduce the temperature of the flame. Sulfur is highly flammable and supports combustion. Glass powder is added to increase friction.
The composition of the match head changed during this time only in a quantitative ratio, mainly due to the addition of inert materials to control the burning rate: zinc white, chrompeak. The mixture also includes animal glue, fastening all the components. Water-soluble dyes are sometimes added.
The composition of the mixture on the side of the box is: antimony sulfide and red phosphorus, in which inert substances are also added so that when igniting one match the whole box does not flash. It can be the same glass powder, gypsum, kaolin, iron minium.
Chemical reaction of combustion
Conventionally, the chemical reaction of ignition of a match during friction against boxes can be expressed by the equation
16KClO 3 + 3P 4 C 3 -> 16 Kcl + 9 SO 2.
The main chemical elements are Bertoletova salt, which is part of the match head, and red phosphorus. Sulfur gas with a characteristic odor is released during the reaction.
And to ignite the box?
Under certain conditions, the match can be lit by friction against a surface not covered by a special composition for the box. For this, a different chemistry of the match head is used.
Besterless - that's what they are called. They are able to ignite when rubbing against any rough surface. Produced in the USA and England, mainly for army needs, called strike anywhere. Of what the matches, which are often shown in American films, are made of, many are interested.
The incendiary head is made of two different compositions of chemicals and contains P4S3 phosphorus sesquisulfide, a non-toxic sulfur compound.
An adhesive mixture of sulfur, bertholite salt, rosin, antimony trisulfide, phosphorus sesquisulfide and inert and stabilizing components are applied directly to the paraffin-impregnated straw.
After the base layer is dried, the top layer of the match head composition is applied to the incendiary head, containing the same components, but in different proportions: a larger amount of phosphorus sesquisulfide, bertholite salt, and finely divided glass powder.
When friction of the incendiary head under the influence of heating, the highly reactive chemical is ignited by a blue flame and ignites the remaining components of the incendiary head.
In addition to all familiar household (in five-centimeter boxes), matches are produced for specific purposes:
- fireplace and gas - larger for ease of use;
- for kindling cigars and pipes;
- household - in large packages;
- all-weather - for lovers of extreme types of recreation; ignite even in the most adverse weather conditions;
- signaling - they burn with a bright, visible flame from afar; magnesium is added to the match head mixture.