Abstract:

A nonconventional method for the evaluation of emulsion stability was developed. The method was valid for viscous emulsions. The technique is based on elec. cond. measurements during nondestructive short-cooling-heating cycles carried out on cosmetic viscous emulsions. Cond. curves were obtained on a recorder, where the second heating cycles were lower and almost parallel to the first heating curves. The bigger the cond. differences between the two heating curves, the lower was the emulsion stability. A relative Stability Index $Δ$/h, indicating relative change in cond. between 2 cycles was elaborated. This index was useful for detg. optimal required hydrophile-lipophile balance values for required emulsions, optimal amt. of oily phase and emulsifier concn. [on SciFinder(R)]