講者：Prof. 山村方人(Masato Yamamura)(日本九州工業大學) 演講題目：Thin Film Processing of Complex Fluids 演講時間：12/1~2 參看附件時間表 演講地點：台大生物技術研究中心1F演講 主持人：廖英志教授等 Abstract Coating and drying technologies of complex fluids such as nanoparticle suspensions, polymer blends, emulsions, and liquid crystals, have received considerable attentions in fabricating advanced thin film devices with particular optical/electrical properties. Industrial demands to produce such products requires new science not only to solve problems on fluid dynamics and separation engineering but also to create new interfaces with desirable size/microstructures inside the liquid at high speeds. In this presentation, recent advances in thin film processing of complex fluids will be addressed, particularly focusing on some key contributions of chemical engineers. A vertical self-stratification of particles in an evaporation suspension film is presented as one of the problem on battery and conductive ink applications. First, some theoretical approaches [1-2] will be introduced to show that particles with larger size will preferential segregate at the top surface. Next, experimental results will be presented to show an opposing situation of surface migration of smaller particles. Recent fluorescence microscopy visualization [3] combined with a physical modeling provides an evidence of “two-step” particle migration, which allows us to partly explain the discrepancy between the previously-reported theoretical/experimental observations. 
References: [1] Cardinal et al., AIChE Journal, 56, 2769 (2010) [2] Buss et al., Journal of Colloid and Interface Science, 359, 112 (2011) [3] Lim S., Ahn, K.H., Yamamura M., Langmuir, 29, 8233–8244 (2013)