Molecular Interactions in Aerosol Emulsion Systems. III. Pearlescent Structures

Synopsis--Specific combinations of the polyoxyethylene fatty ethers and fatty alcohols or acids exhibit considerable pearlescence or iridescence in aqueous or aqueous aerosol systems. As a result of the high aesthetic appeal of these systems, they should be useful for the for-mulation of cosmetic and pharmaceutical products. The pearlescence that is produced depends upon the particular polyoxyethylene fatty ethers, fatty alcohols, and fatty acids that are present, and also upon their concentrations and ratios to each other. The pearlescence is sensitive to temperature, and all of the products ultinmtely lose their pearlescence at higher temperatures. The loss of pearlescence occurs over a temperature range rather than at a specific temperature. This behavior in conjunc-tion with the optical properties of these systems, indicates that they belong to the class of substances having mesomorphic or liquid crystalline structures. Acrosols prepared from the aqueous concentrates generally discharge as foamy liquids which subsequently expand into foams. The propellant can affect the pearlescence of the aqueous concentrates, particularly if the molecular complex has some affinity for the pro-pellant.