Imbibition dynamics on surfaces of legs of a small animal and on artificial surfaces mimicking them

Recently, imbibition of textured surfaces covered with homogeneous micro-pillar arrays has been actively studied partly because of the potential for transport of a small amount of liquids. In most cases, the dynamics is described by the Washburn law, in which the imbibition distance scales with the square root of elapsed time, while a different scaling law has been recently found [1]. In this study, we studied imbibition on legs of a small animal that absorbs water via its legs [2] to find yet another scaling law. Furthermore, imbibition of artificial surfaces mimicking the leg surface was found to be described well by a composite theory.\\[4pt] [1] Obara and Okumura, Phys. Rev. E 86, 020601R (2012).\\[0pt] [2] Ishii, Horiguchi et al. Sci. Rep. 3, 3024 (2013).