Skip to content

Have you ever spilled your cup of coffee? You may have noticed how the coffee dries into an intriguing stain with a bright centre and a dark ring encircling it. This “coffee ring” forms because the liquid evaporates faster at the edges, inducing a flow from the droplet interior towards the outside. Suspended solid coffee particles thus accumulate at the drop edge, causing the characteristic ring pattern.

In Nature Communications, we present a simple, yet versatile strategy to overcome the omnipresent coffee ring effect and achieve homogeneous drying patterns of particle dispersions. Our trick is to modify dispersed particles with surface-active polymeric additives. This induces additional steric repulsion, which prevents particle accumulation at the droplet edge and promotes adsorption to the droplet surface, resulting in a homogeneous particle film upon drying. Importantly, the presented method is independent of particle shape and applicable to a variety of commercial pigment particles and different dispersion media.

 


Self-Assembled Materials
Privacy Overview

This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.