8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

Thu 811:10-14:00P7.85Shaping liquid on tunable microwrinklesTakuya Ohzono 1 and Hirosato Monobe 21 AIST, Ctr. 5 1-1-1 Higashi, 305-8565, Tsukuba, Japan2 AIST, Ikeda, Osaka, JapanMethods of shaping and manipulating liquids on small scales are important for micro-patterning,microfluidics, and biosensing, and may provide fundamental insights into nonlinear chemical phenomenain confined small spaces. Here, we report a simple technique for shaping liquids intomicrometer-scale filaments. Microgrooves on microwrinkles generated by thin film buckling onelastic substrates can function as open channel capillaries for liquids with appropriate wettabilities.Tuning the groove depth of the microwrinkles by modulating strain, we explore the capillaryaction of various liquids in microgrooves, which form liquid filaments emanating from a largereservoir. This behaviour is explained in terms of sinusoidal-geometry-dependent surface energy.Based on this concept, a regular array of liquid filaments can be formed over a large area by asimple coating method, and these filaments can be further reshaped by exploiting strain-inducednonlinear changes in microwrinkle topography. With this technology, we will be able to utilizethe liquid micropatterns for further patterning and to study the nonlinear chemical system at smallscale, where the shape of the liquid solution and the interface become important.Ref. Ohzono et. al.Soft Matter 5, 4585-4844 2009;Langmuir 26, 6127-6132 2010;Small, in press, 201185