Assessing the effects of formulation variables on the water resistance, rheological and texture properties of O/W emulsions

Water resistance is a desirable property across a range of cosmetic product categories, including decorative cosmetics, leave-on hair products, sun protection and skin care (e.g. hand barrier creams). It could be achieved using one or more of the following formulation approaches: high concentration of non-polar emollients, specific combinations of emulsifiers and the inclusion of film-forming polymers. This work has focused on two formulation variables, the type of emulsifier system and the choice of film-forming polymer, both known to change the rheological profiles of semisolid systems. The aim of this study was to assess the effects of these two factors on the rheological and texture profiles, as well as the water resistance characteristics, of semisolid O/W emulsions.