Cosmetic powder suspensions in compliant, fingerprintlike contacts

Biointerphases. 2011 Sep;6(3):126. doi: 10.1116/1.3640042.

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.

MeSH terms

  • Cosmetics / chemistry*
  • Friction
  • Humans
  • Lubricants / chemistry*
  • Particle Size
  • Powders / chemistry*
  • Surface Properties*
  • Suspensions / chemistry*

Substances

  • Cosmetics
  • Lubricants
  • Powders
  • Suspensions