BioPRIA and Department of Chemical Engineering, Monash University, Clayton, VIC 3800, Australia.
Dept. of Chemical Engineering & Biotechnology, University of Cambridge, Cambridge, United Kingdom.
J Colloid Interface Sci. 2021 Jun;591:52-57. doi: 10.1016/j.jcis.2021.01.092. Epub 2021 Feb 1.
Pattern formation is a common occurrence in drying colloidal systems. The most common in droplets, is a ring distribution where the constituents have relocated to the edge, which is referred to as a coffee ring. This deposit is unfavourable in many manufacturing processes and is of fundamental interest. In this study, we present a model capable of predicting when a coffee ring will be observed in hard spherical particle systems. Ring profiles are found to be formed at low contact angles with the specific angle predicated upon the initial concentration of the suspension. Modelling results are in agreement with experiments using latex suspensions.
图案形成是干燥胶体系统中常见的现象。在液滴中最常见的是一种环形分布，其中的成分已经迁移到边缘，这被称为咖啡环。这种沉积物在许多制造过程中是不利的，因此具有重要的研究意义。在这项研究中，我们提出了一个能够预测硬球粒子系统中何时会出现咖啡环的模型。研究发现，在低接触角下会形成环形轮廓，而特定的接触角则取决于悬浮液的初始浓度。使用乳胶悬浮液的实验结果与模型结果吻合。
