Replication of rose-petal surface structure using UV-nanoimprint lithography

Rose-petal surface consists of a hierarchical structure of microscale papillae and nanofolds. With this micro-nanostructure and surface energy, rose petals exhibit a special property: drops on the petal surface are spherical and do not slide when a petal is held upside down. We replicated the rose-petal surface structure by employing a UV nanomolding process using polyurethane acrylate (PUA) for the first replica and perfluoropolyether (PFPE) for the second replica. PFPE micro-nanostructures, which were identical to the rose-petal hierarchical structure, were formed on a glass substrate. The water contact angle of 144 degrees and contact-angle hysteresis of 83 degrees confirmed that the surface of the glass substrate exhibited a high adhesive force and superhydrophobicity. (C)2014 Elsevier B.V. All rights reserved.