O/W emulsifier, O/W emulsion and applications thereof

#The invention concerns an O/W emulsifier, an O/W emulsion prepared therefrom and the uses thereof.

#As the largest organ in the human body, the human skin performs many vital functions. With an average surface area of approximately 2 m2 in adults, it has a prominent role as a protective and sensory organ. It is the job of this organ to communicate and repel mechanical, thermal, actinic, chemical and biological stimuli. It also has an important role as a regulatory and target organ in the human metabolism.

#Cosmetic skin care is primarily concerned with reinforcing or restoring the natural function of the skin as a barrier against environmental influences (e.g. dirt, chemicals, microorganisms) and against the loss of bodily substances (e.g. water, natural fats, electrolytes) and to support the natural regeneration ability of its stratum corneum if it becomes damaged. If the barrier properties of the skin are disrupted, this can lead to greater resorption of toxic or allergenic substances or to attack by microorganisms, resulting in toxic or allergenic skin reactions. A further objective of skin care is to compensate for the loss of fat and water in the skin caused by daily washing. This is especially important if the natural regeneration ability is not adequate. Skin care products should also protect against environmental influences, particularly sun and wind, and delay skin ageing.

#The glyceryl oleate citrate is preferably an ester of monooleic and/or dioleic acid glycerides with citric acid, wherein the ester is obtainable in particular by esterification of citric acid with monooleic acid glyceride in a molar ratio of 0.3:1 to 1.5:1, preferably 0.7:1 to 1.2:1. In particular, glyceryl oleate citrate with the aforementioned properties improves the stability of the O/W emulsifier and emulsions based thereon.

#It is also preferable for the glyceryl oleate citrate to have a pH in the range from 5 to 8, in particular 5.8 to 6.2, in particular 6.0 (measured in each case in a 10% 1:1 water/methanol blend) through neutralisation. Fully neutralised esters are particularly preferred. Sodium hydroxide, for example, is suitable for neutralisation.

#The glyceryl oleate citrate in the O/W emulsifier according to the invention preferably has an HLB value in the range from 9 to 15, in particular 11 to 13.