System for preparing a personalized composition using pressure

Preparation and dispensing system for preparing and dispensing a personalized composition from N reserves (501-508) of active compounds (A1-A2), N being an integer greater than or equal to 1, each one having a determined hydraulic resistance (Rh2) and each one comprising a fluid inlet (511-518), a fluid outlet (521-528) and a body (530) comprising at least one active compound, characterized in that it comprises a pneumatic-pressure generator (200, 201-202) connected to a pressure distributor (300) comprising N pressure changeover switches (301-306), each one having at least one inlet (I1) connected to the pressure generator, one inlet (I2) connected to atmospheric pressure and an outlet (311-316) connected to an inlet of a reserve of active compound (A1-A2), such that each reserve (501-508) of active compound (A1-A2) can be placed in communication either with atmospheric pressure, or with the pressure generated by the pressure generator, and in that each reserve of active compound comprises, at its fluid outlet, an ejection nozzle (500) the hydraulic resistance (Rh1) of which is higher than the hydraulic resistance (Rh2) of the said reserve of active compound.