Patent No. US 7,399,479 B2. Wella AG, Darmstadt, Germany, has been granted a patent covering a microemulsion with an aqueous phase and an oil phase. It is comprised of, by weight, 20-60% water; 3-20% of an oil phase comprised of hydrophobic oil that is liquid at 25°C and, optionally, dissolved lipophilic materials; and 20-60% of an emulsifier mixture that contains one emulsifier from the group consisting of ethoxylated castor oils and ethoxylated hydrogenated castor oils and a second emulsifie...