Security printing has been performed for years to combat against counterfeit documents. In this research hydrophobic silica nanoparticles are suspended into an ink and printed on paper and glass substrates. It was shown that under certain conditions superhydrophobic substrates could be created. In addition, a superhydrophobic security-feature was printed using these methods.
Michelle Jensen, Jacob Petersen, Chris Schultz, Jon Kellar, William Cross, "Ink Formulation and Printing of Superhydrophobic Paper" in Proc. IS&T Printing for Fabrication: Int'l Conf. on Digital Printing Technologies (NIP33), 2017, pp 42 - 46, https://doi.org/10.2352/ISSN.2169-4451.2017.33.42