Next Generation Mildness for Personal Care: Nonpenetrating Polymerized Surfactants for Cleansing Applications

摘要

Surfactants are essential ingredients in nearly all personal cleansing formulations, from bar soaps to shampoos and liquid body washes. The amphiphilic nature of surfactants causes them to exhibit unique phenomena, such as surface and interfacial adsorption and self-assembly into aggregated structures, e.g. micelles and lamellae. These phenomena are the basis for the utility of surfactants in personal cleansers, which includes detergency, foaming, viscosity building, and solubilization of active ingredients and fragrances. However, this amphiphilic nature also causes surfactants to readily interact with biological substrates, such as the lipids and proteins that comprise the stratum corneum (SC) of the skin. During cleansing, surfactants can penetrate into the SC and damage its structure. This damage to the skin barrier and the ensuing inflammatory response are collectively referred to as irritation, and the small molecule surfactants typically employed in personal cleansers can present a significant irritation risk if they are not formulated properly.