Method for releasing an active principle contained a multiple emulsion

A process for releasing an active principle comprising a multiple emulsion wherein the multiple emulsion comprises a water-in-oil-in water emulsion comprising an inverse emulsion Ei with an aqueous phase A1, in dispersion in the form of droplets of direct emulsion Ed, in a continuous aqueous phase A2, wherein the emulsion Ed is stabilized by a surfactant having an HLB of greater than 14 present in its continuous phase;

• the emulsion Ei is stabilized by a surfactant having an HLB of less than 7 present in its continuous phase;
• and the amount of the surfactant present in the aqueous phase A2 of the emulsion Ed is adjusted to an amount greater than the critical concentration threshold of this surfactant, for converting said multiple emulsion into a direct-emulsion, with a concentration threshold being between 7 and 20 CMC (Critical Micelle Concentration) for a surfactant having an HLB of the order of 40 and greater than 100 CMC for a surfactant having an HLB between 14 and 20 CMC;
• wherein the active principle is in solution in the aqueous phase A1 and said active principle is released into the aqueous phase A2 by adjusting the concentration of the surfactant present in said aqueous phase A2 with the release time being shorter at concentrations equal to or greater than this surfactant's critical concentration threshold.