MARK CHANDLER*¹,TONY O’LENICK^2
*Corresponding author
1. ACT Technologies, Newark, DE 19713, USA
2. Siltech LLC, Lawrenceville, USA

Abstract

For oil in water (O/W) emulsions, Appearance, Pick-up, and Rub-out (APR) aesthetic characteristics are all dictated by emulsifier selection; in After-feel evaluations, there is an equal influence of emulsifier and emollient(1).  This was all laid out elegantly by Dr. Johann Wiechers and the team back in 2002. This current study demonstrates that invert (water-in-oil and water-in-silicone) emulsions made with PEG-free TMP Lauryl Dimethicone emulsifier had different aesthetic characteristics when compared to the same emulsions using the very similar Lauryl PEG-8 Dimethicone emulsifier.  

Overall, it was demonstrated that invert (water-in-oil) emulsions have similar   properties from their oil-in-water counterparts in terms of APR and After-feel characteristics  but the emulsion characteristics are also effected by the emollient in an invert emulsion.

This  study was undertaken by Siltech and ACT Technologies and  was presented by Mark Chandler of ACT Technologies at the IPCE in 2018 in Italy.

INTRODUCTION

It has been demonstrated that oil-in-water emulsion aesthetics, with Appearance, Pick-up, and Rub-out in particular, are controlled by the emulsifier selection, while After-feel characteristics show influence from both emulsifier and emollient choice (1).  Water-in-oil and water-in-silicone emulsions, a platform not extensively evaluated by previous aesthetic studies (2), represented a new layer of exploration. The initial drive was to find differences in these systems with a change in emulsifier. Once an ideal emulsifier had been determined, the next step involved discerning the changes in aesthetic characteristics from varying emollients, all the while maintaining a constant emulsifier. The differences between the two emulsifiers tested was strictly in the nature of the hydrophilic portion, with TMP Lauryl Dimethicone being trimethylolpropane, and Lauryl PEG-8 Dimethicone, a polyethylene glycol (PEG) chain. The emollients tested included Heptyl Undecylenate, Ethylhexyl Palmitate, Diheptyl Succinate (and) Capryloyl Glycerin/Sebacic Acid Copolymer, and Diheptyl Succinate and Capryloyl Glycerin/Sebacic Acid C ...