Stable water in oil emulsion systems for cosmetic and pharmaceutical preparations

摘要

A highly stable water in oil emulsion system for cosmetic or pharmaceutical preparations is provided wherein an unexpectedly high proportion of from about 70% to about 80% of an internal aqueous phase may be dispersed as globules usually of about one micron in a continuous external oleaginous phase by use of an emulsifier composition containing cooperatively effective amounts of (1) a di- or tri-valent salt of the esterification product of a C10 to C22 fatty acid with a hydroxy carboxylic acid containing 2 to 4 carbon atoms (preferably calcium stearoyl-2-lactylate), and (2) a co-emulsifier compatible with emulsion (1) having an HLB value and present in a quantity to cause said emulsifier composition to have an effective HLB value within the range of about 4.6 to about 6.6. An emulsion may be produced using simple mechanical mixing techniques which has a static shelf life of at leat about six months at approximately 25 DEG C.