Abstract
Organoclay, which is prepared by exchanging the original interlayer cations of smectite mineral for quaternary alkyl-ammonium ions, is known to form a complex with surfactants in liquid paraffin or other oils and to give oil-gel. By adding an adequate amount of water, the oil-gel obtained from the complex can give a W/O type emulsion, which has been used in skincare cosmetics, foundations and other products. Conventionally, decamethyl cyclopentasiloxane and silicone type surfactant have been used to provide the emulsion formulae having a good sensory-texture. In this study, for providing skincare products with high skin compatibility, new oil-gel and W/O emulsion formulae were attempted to be prepared with isohexadecane, which can give a higher smoothness and compatibility to the skin than that of decamethyl cyclopentasiloxane. By selecting suitable nonionic surfactants for isohexadecane, stable W/O emulsion formulae were prepared with a smaller amount of the surfactant than in the conventional technique. W/O emulsion formulae obtained in this way were found to have a higher skin-compatibility and lower stickiness than that of the conventional emulsions. Additionally, it was found that not only the interlayer distance of the organoclay but also the interaction between organoclay and surfactants has important functionalities in the oil-gel formation.
