In a distributing device for liquid preparation composed of three parts forming a single unit consisting of a receptacle, an intermediate part of a flexible texture forming a bellows fixed on the neck of the receptacle and an upper part mounted on the top of the bellows forming a reservoir finished by a nozzle closed at its ends. The intermediate part is composed of a flexible sleeve formed of several concentric rings joined together, inside which are arranged two impervious membranes separated by a rigid member having two sharpened extremities arranged vertically, perpendicular to each of the two membranes.