Method of preparing natural oil-containing emulsions and microcapsules and its uses.


The invention relates to a process for prepg. a chitosan-contg. aq. emulsion of an oil comprising the steps of (a) forming an oil-in-water emulsion by homogenizing the oil into an aq. soln. contg. an anionic emulsifier; and (b) adding to the emulsion obtained in (a) an aq. chitosan soln. while continuously homogenizing the mixt. to give a stable emulsion. In further aspect the invention relates to a process for the microcapsulation of fine oil droplets. The invention also relates to sustained-release biodegradable prepns. comprising as active ingredient vitamin E or a UV radiation photoprotectant or a lice repelling agent comprising at least one natural oil or natural oil component thereof and further comprising an anionic emulsifier and chitosan. A lice-repelling emulsion contained rosemary oil 15, chitosan 0.5, citric acid 5, lecithin 0.35, and water 79.15%. The final pH of the emulsion was 3.5 and the emulsion was stable for ≥8 mo at room temp. When the emulsion was applied to human hair fibers, the chitosan microcapsules contg. rosemary oil adhered well to the fiber. [on SciFinder(R)]


CAPLUS AN 1996:147818(Patent)