Patent ID: 6607733
Filing Date: 2003-08-19
Classification: A61K,A61Q,Y10S

Abstract:
An oil-in-water microemulsion in the form of a gel, said oil-in-water microemulsion comprising:a) a continuous aqueous phase; b) a discontinuous oil phase in the form of a microemulsion droplets; c) a content of less than 20% of the weight of the microemulsion of one or more emulsifiers selected from the group consisting of: i) polyethoxylated oil-in-water emulsifiers; ii) polypropoxylated oil-in-water emulsifiers; and iii) polyethoxylated and polypropoxylated O/W emulsifiers; and wherein said one or more emulsifiers optionally further comprise of water-in-oil emulsifiers; and d) one or more crosslinking substances joining said microemulsion droplets together, wherein the molecules of said crosslinking substances contain at least one hydrophilic region which contains an extension which bridges the distance between at least two microemulsion droplets and at least one hydrophobic region which forms a hydrophobic interaction with at least one of the microemulsion droplets, â€ƒwhich is prepared by a process comprising: a) mixing base components of the aqueous phase, base components of the oil phase, and said emulsifiers to form a mixture thereof; and b) varying at least one parameter selected from the group consisting of temperature and the concentration of emulsifiers, the oil phase and the aqueous phase so that the mixture passes through a phase inversion range between water-in-oil emulsions and oil-in-water emulsions and is brought into a range where the mixture is present as an oil-in-water microemulsion; wherein said crosslinking substances are added to said mixture at any time during the process.