EVALUATION OF THE HYDROPHILE-LIPOPHILE BALANCE (HLB) OF NONIONIC SURFACTANTS .1. MULTISURFACTANT SYSTEMS

Since the hydrophile-lipophile property of nonionic surfactant for a given system is just balanced in a three-phase region of a phase diagram which is a stack of three-phase triangles consisting of an aqueous, a surfactant, and an oil phase, we defined the hydrophile-lipophile balance (HLB) plane on which the three-phase triangle is positioned in the midst of the three-phase region. In a three-component system of nonionic surfactant/water/oil, the HLB plane is located at fixed temperature (T//H//L//B). Accordingly, the equation of the HLB plane is represented by T equals T//H//L//B in this system, and, hence, the phase inversion temperature of emulsion (PIT) is independent of a surfactant concentration.