title: Cosmetic powder suspensions in compliant, fingerprintlike contacts.
abstract: Cosmetic powders are regularly employed in skin creams and cosmetic formulations to improve performance and enhance skin feel. A previous study investigated the effect of particle concentration and size on the lubricating properties of powder suspensions in smooth, compliant contacts [Timm et al., Tribol. Int. (2011)]. In this paper the tribological properties of cosmetic powder suspensions are investigated in compliant contacts having model fingerprintlike surface topography. Friction coefficients were measured for a series of powder suspensions with varying particle size and concentration in a polydimethylsiloxane (PDMS)/PDMS contact. A commercial tribometer (MTM, PCS Instruments) was employed to measure friction as a function of rubbing time (20 min), under pure sliding (50 mm/s) and low load (0.5 N) conditions. Compared to results using smooth surfaces, it was clear that surface topography has a pronounced affect on the time-dependent tribological behavior of the cosmetic powder suspensions studied. A two-stage friction coefficient versus time curve was observed. By varying the particle size and concentration it was shown that the duration and magnitude of each stage can be controlled.
authors.affiliation: Beiersdorf AG, Research & Development, Unnastraße, Hamburg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Timm
authors.forename: C
authors.initials: C
authors.lastname: Myant
authors.forename: H A
authors.initials: HA
authors.lastname: Spikes
authors.forename: M
authors.initials: M
authors.lastname: Schneider
authors.forename: T
authors.initials: T
authors.lastname: Ladnorg
authors.forename: M
authors.initials: M
authors.lastname: Grunze
mesh_terms: D003358:Cosmetics / Q000737:chemistry*; D017276:Friction; D006801:Humans; D054327:Lubricants / Q000737:chemistry*; D010316:Particle Size; D011208:Powders / Q000737:chemistry*; D013499:Surface Properties; D013535:Suspensions / Q000737:chemistry*
chemical_list: D003358:Cosmetics; D054327:Lubricants; D011208:Powders; D013535:Suspensions