Fabrication of hydrophobic films replicated from plant leaves in nature

In this study, we have investigated the feasibility of reproducing the hydrophobic characteristics of plant leaves from nature by replicating the micro/nano features of a leaf surface in a UV curable polymer film. Films were fabricated by means of UV-nanoimprint lithography (UV-NIL) technology. By varying UV-NIL processing conditions, we were able to produce hydrophobic films which replicated the micro/nanostructure of leaves. The surface topology of those replicated films was observed by a scanning electron microscope (SEM) and an atomic force microscope (AFM). Also for the purpose of evaluating the hydrophobicity of the replicated film surface, water contact angle (CA) was measured. CA values of the replicated films turn out to be a little smaller than that of nature, and yet large enough to offer excellent hydrophobic characteristics to the film. We propose a new measure of replication quality to evaluate how well the film can reproduce the micro/nanostructures of natural plant leaves. In terms of these measurements of CA and replication measure (R), we were able to confirm that the UV-NIL could be a possible tool to produce a hydrophobic film by replicating surface of plant leaves.