Patent ID: 6235298
Filing Date: 2001-05-22
Classification: A61K,A61Q

Abstract:
A W.sub.1 -O-W.sub.2 multiple emulsion comprising:(1) about 1% to 99% by wt. of the composition of a W.sub.1 /O emulsion comprising;(a) about 1% to 99% of said emulsion of an internal aqueous phase comprising (i) water; (ii) 0.01 to 30% by wt. emulsion solute; and (iii) optional surfactant;(b) about 0.5% to about 99% of the emulsion of an oil phase surrounding said internal aqueous phase wherein said oil is selected from the group consisting of volatile hydrocarbon, nonvolatile hydrocarbons, nonvolatile silicones and mixtures thereof;(c) about 0.1 to about 20% by wt. emulsion of a surfactant emulsifier selected from the group consisting of a silicon-free surfactant or surfactant blend having an HLB value of about 10 or less, an oil soluble silicon based surfactant, an oil-soluble polymeric surfactant and mixture thereof; and(d) a topically effective amount (0.01-40%) of a first topically active compound, which may be found in either the aqueous phase (a), oil phase (b) or both; and(2) about 1 to 99% by wt. of an external isotropic aqueous phase W.sub.2 comprising:(a) 2 to 80% by wt. aqueous phase of a surfactant phase which comprises a non-amido anionic, or a mixture of anionic and amphoteric in which 60% by weight or greater is the anionic surfactant;(b) 0 to 60% by wt. of external phase of a second topically active compound;(c) optional solute; and(d) 0.01 to 10% of a nonionic natural gum stabilizer wherein the multiple emulsion droplets maintain their integrity and the multiple emulsion composition does not phase separate.