Red phosphorus-chlorate compositions

This is not as sensitive as the red phosphorus-chlorate composition but is one of the most dreadful firework compositions. It is used for cracker balls, the last noise of smoke bombs, small rockets etc., under the name, "Red explosive". The wet process is recommended for the manufacture of these items, but the dry process is commonly used except for cracker ba lls. 

The sporting paper caps which are used for starting signal pistols in Japan each contain about 0.05 g of a composition consisting of 74% potassium chlorate, 18% red phosphorus, 8% sulphur and small amount of starch. Recently, the hazard classification on the packaging of these paper caps for transportation on ships was discussed. 

CAUTION Red phosphorus is a dangerous compound. Respirators should be worn while handling this component and care taken to ensure that the dust is not ingested, breathed or allowed contact with the skin. DO NOT use any container or other utensil that has at any time been used with potassium chlorate or any chlorate salt. An explosion is a certainty. I have a picture of a bomb squad crewmember with his hand turned into a mist by this compositions detonation and it does not look at all pleasant. 

The detonator (discriminating impact fuse) is a brass cup 3/16 V3/16 The wall thickness is about half that of a conventional primer. The Interior of the cap Is coated with a shock sensitive explosive, probably the same composition found in toy pistol caps (Pottasiym Chlorate, Red Phosphorus and Black Antimony Sulfide). The volume used is also about that of a toy cap. The cup is seated open end to the rear and is recessed about... 

Generally firework compositions which contain potassium chlorate, perchlorate or ammonium perchlorate as oxidizer will detonate from a strong mechanical initiation, especially when the composition are in the powdered state.Potassium chlorate or other chlorate, red phosphorus, realgar, sulphur, antimony trisulfide etc. promote the inclination. On the contrary, potassium nitrate or other nitrates decrease it. Black powder is not likely to detonate. 

Potassium perchlorate becomes sensitive in contact with red phosphorus the mixture detonates with a loud noise by an impact between metal pieces of aluminium or bronze. When the mixture is ignited, it detonates instantaneously. However match or toy pistol caps cannot be made from compositions which contain potassium perchlorate in place of chlorate, because the ignition is uncertain. When potassium perchlorate is mixed with realgar, antimony trisulphide, sulphur etc. it also becomes sensitive realgar particularly increases the sensitivity to friction. But the degree of sensitivity is not as large as it is with potassium chlorate. 

When ammonium perchlorate is mixed with red phosphorus it becomes very sensitive to shock, but not so much to friction. With realgar, sulphur, antimony trisulphide etc. it also becomes sensitive almost like the above. The degree of shock sensitivity of ammonium perchlorate due to such substances is almost the same as that of potassium chlorate, but higher than that of potassium perchlorate. The low friction sensitivity of ammonium perchlorate due to these substances is one of its attractive features in comparison with potassium chlorate and perchlorate(T.Shimizu Sensitivity tests on firework compositions, J. Exp.Soc. Japan, 2, No.6, p. 3 3... 

The wet process is used for manufacturing cracker balls(the composition consists of realgar and potassium chlorate), paper caps (red phosphorus, sulphur and potassium chlorate) and pull-igniters (red phosphorus, antimony trisulphide and potassium chlorate). 

In Japan industrial fuse(Bickford) has recently been used in place of the hand made fuse the manufacture of the latter is quite labour intensive. In order to catch fire from some other heat source or to transfer the fire to other pieces the two ends of a cut fuse are pasted with a slurry of a prime composition. Sometimes a match composition which contains chlorate is pasted on one end so that it is ignited when it is rubbed with a red phosphorus striker. In general the slurry is a mixture of black powder and 10% nitrocellulose solution in acetone. In place of the nitrocellulose, celluloid solution can also be used. The ratio of the black... 

B) includes noise compositions which are quite sensitive and snake compositions which exhibit curious phenomena, etc. It can be seen from the diagram that toy firework compositions, (A+B), are more numerous than those for ordinary fireworks (A). The reason is that, in the case of toy fireworks it is possible to increase the safety of the compositions to a high degree by complete division and isolation. Following this principle even some sensitive compositions which are never used for shells, exhibition fireworks etc. can be used for toy fireworks. For example, a composition which contains potassium chlorate and red phosphorus is used for pistol caps or another compositon which contains potassium chlorate and realgar is used for cracker balls. These compositions are generally used only for toy fireworks. 

Compositions. Red phosphorus, sulphur, realgar, antimony trisulphide or other sulphides should possibly be rejected from the compositions. It is the same to chlorates also. These materials increase the sensitivity of almost all compositions. However in practice, the requirement is not always satisfied sufficiently, and each one must be considered individually. The sensitivities in Table 28, 29 and 30(Chapter 27) may be used for planning compositions correctly. On the other hand, select each of the components so that no chemical reaction can occur among the materials. Generally a mixture of metal powder and oxidizer or chloride will cause a chemical reaction to evolve heat in presence of water. Metal powder is sometimes damaged by corrosion, and generally the grains must be coated by some... 

For safety potassium chlorate is firstly mixed with a sufficient quantity of water and then starch, sulphur and red phosphorus are added to it into a slurry. (Some products from other countries use a black composition which contains antimony trisulphide in place of sulphur.) Prepare a metal plate which has many small holes arranged across it(Fig.133.1). Place it on a paper sheet place an amount of the slurry composition on the plate and slide and squeeze the composition over the surface of the plate. 

The S. and C. composition varies, according to whether it it to be used for paralfined or sulphured splints, or for waxed threids. The ordinary composition is as follows —6 parts of phosphorus sesquisulj de, 34 parts of potassium chlorate, 6 parts of tine oxide (zinc white), 6 parts of red ochre, 6 parts of powdered glass, 6 parts of glue, and 34 parts of water. It is easy, by manipulation, to make these matches either more or less inflammable. The mechanical processes are much the tame as in the manufacture of phosphorous matches. 

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