Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
J Colloid Interface Sci. 2010 Nov 1;351(1):283-7. doi: 10.1016/j.jcis.2010.07.037. Epub 2010 Jul 21.
Recent research on the flow patterns during the drying of droplets of solutions or suspensions has revealed a characteristic flow of dissolved or suspended material to the droplet periphery to produce the 'coffee ring' phenomenon. This effect was used to make ceramic well-plates by spontaneous manufacturing. Here we demonstrate that when a colloidal droplet dries on a superhydrophobic surface, the effect is rather different. Evaporation from the region adjacent to the three phase line becomes so restricted that the interior flows, and hence the final destination of particles, changes and the characteristic bowl-shape becomes inverted.
最近对溶液或悬浮液液滴干燥过程中的流型的研究揭示了溶解或悬浮物质向液滴周边流动的特征，从而产生了“咖啡环”现象。这种效应被用来通过自发制造来制作陶瓷井板。在这里，我们证明了当胶体液滴在超疏水表面上干燥时，效果则大不相同。由于靠近三相线的区域的蒸发受到如此大的限制，以至于内部流动，因此颗粒的最终目的地发生变化，特征碗形倒置。
