Scalable Nanopillar Arrays with Layer-by-Layer Patterned Overt and Covert Images

Abstract

Transferring flexible and scalable nanopillar arrays on a variety of unconventional substrates, including fabric, paper, and metals, is achieved by a single-step replication process using UV-curable polymers. Local alteration of the contact angle on the nanopillar arrays by LBL films creates selectively hidden images. They can be revealed by the breath and used as an innovative anti-counterfeit technology.