Abstract
Ring formation in an evaporating sessile drop is a hydrodynamic process in which solids dispersed in the drop are advected to the contact line. After all the liquid evaporates, a ring-shaped deposit is left on the substrate that contains almost all the solute. Here I show that the drop itself can generate one of the essential conditions for ring formation to occur: contact line pinning. Furthermore, I show that when self-induced pinning is the only source of pinning an array of patterns—that include cellular and lamellar structures, sawtooth patterns, and Sierpinski gaskets—arises from the competition between dewetting and contact line pinning.
- Received 24 November 1998
DOI:https://doi.org/10.1103/PhysRevE.61.475
©2000 American Physical Society