Abstract: This invention relates to the preparation of gas bubble-sensitized explosive compositions which are liquid during their manufacture.It is possible to achieve particularly fine bubble sizes and therefore enhanced explosive power by incorporating in the liquid composition a gas bubble-generating agent (either a gas or a substance capable of generating gas) prior to subjecting, or while the composition is subjected, to super-atmospheric pressure, this pressure being sufficient to dissolve at least part (preferably all) of any gas present. The composition is returned rapidly to atmospheric pressure and this creates a fine discontinuous gaseous phase in the composition.The invention is especially useful for preparing emulsion explosives which can be mixed and pumped under pressure, thus substantially avoiding gas bubble disengagement and coalescence.

Abstract: A gas bubble sensitized water-in-oil emulsion explosive composition comprising a discontinuous aqueous phase comprising at least one oxygen-releasing salt, a continuous water-immiscible organic phase, a discontinuous gaseous phase, a water-in-oil emulsifying agent and at least one agent capable of facilitating the production of gas bubbles in the presence of said water-immiscible organic phase.