title: Calculation of optimum emulsifier mixtures for phase inversion emulsification*.
abstract: Synopsis The phase inversion emulsification is a convenient method of preparing fine-disperse and long-term stable oil-in-water emulsions, which are stabilized with nonionic emulsifiers. On the basis of EACN-values (equivalent alkane carbon numbers) the calculation of phase inversion in concentrates (CAPICO) is possible, which yields emulsifier and oil mixing ratios corresponding to a given phase inversion temperature (PIT). The CAPICO-method is illustrated for the example of a cosmetic oil-in-water lotion containing an oil mixture, glyceryl monostearate and a fatty alcohol ethoxylate. Of special interest is the influence of silicone oils on the PIT. At a constant emulsifier oil ratio the complete phase behaviour of this emulsion system is represented in a temperature/water content graph. Optimum emulsification results are obtained if during PIT emulsification a microemulsion or a lamellar phase is passed. The emulsions were characterized by particle sizing, and emulsion stability against sedimentation was evaluated by ultrasonic velocity changes. A fine-disperse and long-term stable oil-in-water emulsion was prepared by a time and energy-saving two-step hot-cold process.
authors.affiliation: Henkel KGaA, D-40191 Düsseldorf, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Förster
authors.forename: W V
authors.initials: WV
authors.lastname: Rybinski
authors.forename: H
authors.initials: H
authors.lastname: Tesmann
authors.forename: A
authors.initials: A
authors.lastname: Wadle