Mercury fulminate dead pressed

Under a pressure greater than 1660 kg/cm2 mercury fulminate becomes dead pressed i.e. takes fire with difficulty and burns without detonation. 

Thus, at a pressure of 200 kg/cm2 the substance nears the condition of being dead pressed . In spite of the fact that burning under this condition passes to detonation with difficulty, when greatly compressed the material maintains its ability to be detonated by a cap. Thus, 0.4 g of tetrazene, pressed under a pressure of 200 kg/cm2, develops its maximum power, i.e. 21.1 g of sand crushed, when initiated with 0.4 g of mercury fulminate. The difficulty in passing from burning to detonation makes tetrazene unsuitable for detonators and its application is thus limited to... 

Hexamethylenetriperoxidediamine is almost insoluble in water and in the common organic solvents at room temperature. It detonates when struck a sharp blow, but, when ignited, bums with a flash like nitrocellulose. Taylor and Rinkenbach 63 found its true density (20°/20°) to be 1.57, its apparent density after being placed in a tube and tapped 0.66, and its density after being compressed in a detonator capsule under a pressure of 2500 pounds per square inch only 0.91. They found that it required a 3-cm. drop of a 2-kilogram weight to make it explode, but that fulminate required a drop of only 0.25 cm. In the sand test it pulverized 21/ to 3 times as much sand as mercury fulminate, and slightly more sand than lead azide. It is not dead-pressed by a pressure of 11,000 pounds per square inch. It is considerably... 

TATNB can be dead pressed , like mercury fulminate. 

Woliler patented a detonator mixture of load azide with three parts mercury fulminate, which mixture does not become dead pressed" even when subjected to 2000 atm. pressure. 

Properties Bright-yellow crystals or amorphous powder or granules. Sp. gr. 1.63. Explodes when heated to a temperature of 180°. Less sensitive to impact than either lead azide or mercury fulminate, much less sensitive to friction than the latter, and does not get dead-pressed. Cannot be detonated under water with a No. 8 electric detonator. The strength (sand-bomb test) is about, twice that of mercury fulminate or lead azide. The initiating power is greater than... 

Lead azide is a more efficient detonating agent than mercury fulminate. It requires a higher temperature for its spontaneous explosion, and it does not decompose on long continued storage at moderately elevated tem )cratures. It cannot be dead-pressed by any pressure which occurs in ordinary manufacturing operations. Lead azide pressed into place in a detonator capsule takes the fire less readily, or explodes from spark less readily, than... 

As opposed to mercury fulminate, pure LA cannot be dead-pressed in normal circumstances (even by a pressure of 200 MPa). However, LA prepared in presence of a crystal structure modifier (dextrin, carboxymethyl cellulose, and others) or desensitized (e.g., paraffin) can be dead-pressed dextrinated LA cannot be dead-pressed below 118 MPa and paraffined below 78 MPa [3]. 

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