Intrinsic skin tribological properties drive the perception of skincare absorption

Understanding perceived product absorption remains challenging in cosmetic sensory science because evaluations often exhibit high inter-individual variability and limited reproducibility. This study investigated the relationship between perceived absorption and biometrological and tribological measurements on healthy volunteers. Absorption was defined as the disappearance of wetness together with increased resistance during spreading. Statistical analysis confirmed the absence of an operator effect, indicating that the observed variability originated primarily from intrinsic skin factors. Corneometry identified three hydration-based skin types, while tribological measurements performed on bare skin revealed an intrinsic factor termed skin responsiveness, distinguishing responsive from non-responsive skin independently of hydration level. During product application, three sensory absorption profiles emerged, associated with both hydration and skin responsiveness. Responsive skin exhibited stronger friction dynamics during rub-out. By integrating sensory analysis, biometrology and tribology, this work suggests that intrinsic tribological responsiveness of bare skin may contribute to the inter-individual variability commonly observed in perceived absorption.