Abstract: A stable oil-in-water emulsion, a process for the preparing such emulsion, and a formulation process employing the emulsion. The stable oil-in-water emulsion is obtained from an air-in-water preemulsion to which a simple or complex fatty substance is added by moderate mixing, preferably without exerting a shear force. The air-in-water preemulsion includes a surfactant, preferably a nonionic surfactant, a co surfactant chosen from hydrophilic compounds, preferably having at least one hydroxyl group, which are chosen in particular from the family of the polyols, and an aqueous phase. The ratios of these three components of the preemulsion are chosen within the region of ordered liquid crystal structure of the phase diagram of these three components and/or in ratios chosen so that the structure of the mixture of these three components, observed under a microscope in polarized light, exhibits birefringence characteristics.

Abstract: A stable complex oil-in-water emulsion which is useful in the cosmetic, pharmaceutical or food fields. The stable complex oil-in-water emulsion is formed by the mixing of individual oil-in-water emulsions, each individual emulsion being obtained from an air/water pre-emulsion of a preferably-nonionic surfactant; a cosurfactant selected from hydrophilic compounds, preferably with at least one hydroxyl group selected from polyols; and an aqueous phase. A method of preparing a stable complex oil-in-water emulsion whereby individual oil-in-water emulsions, chosen for properties desired in the stable complex oil-in-water emulsion, are optionally diluted and mixed without exerting a shear force.

Abstract: The invention relates to a stable oil-in-water emulsion which is obtained from an air/water pre-emulsion containing: a preferably-nonionic surfactant; a cosurfactant selected from hydrophilic compounds, preferably comprising at least one hydroxyl group, which are chosen, for example, from the polyol family; and an aqueous phase. According to the invention, the aforementioned three elements are used in ratios that are selected from the ordered liquid crystal structure zone of the phase diagram of said three elements and/or in ratios that arc selected such that the structure of the mixture of said three components when observed under a microscope in polarised light displays birefringence characteristics. Moreover, a simple or complex fatty substance is added to the above-mentioned pre-emulsion by means of mild stirring, preferably without exerting a shear force. The invention also relates to the method of preparing such emulsions and to a simple formulation method making use of said emulsions.