Confined colloidal droplets dry to form circular mazes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40758878.
- Also identified by DOI 10.1073/pnas.2508363122 and PMC identifier 12358886.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
During drying, particle-laden sessile droplets will leave so-called coffee-stain rings behind. This phenomenon is well known and well understood (Deegan <i>et al</i>., <i>Nature</i> <b>389</b>, 827-829 (1997). Here, we show that when particle-laden droplets confined in a slit are allowed to evaporate very slowly, they do not deposit coffee rings, but form surprisingly intricate, circular maze-like patterns. We present experiments that illustrate this pattern formation and discuss the factors that determine when such patterns can form. We are not aware of reports of natural examples of the formation of such beautiful patterns under confinement, although it seems likely that they exist.