Direct gravure printing of indium tin oxide nanoparticle patterns on polymer foils

A direct gravure printing process for UV-curable indium tin oxide (ITO) nanoparticle patterns on polyethylene terephthalate and polyethylene naphthalate foils is presented for use as transparent electrodes. Both large-area coatings and patterns of ITO with thicknesses from 0.2 to > 1 mu m and feature sizes on the order of 100 mu m were realized with a sheet resistance down to 400 Omega square and a transmission > 85% in the visible. In order to reach the lowest sheet resistance, a post-treatment under inert or reducing conditions at temperatures of 130 to 180 degrees C was used. Special requirements regarding the gravure printing of electronic material from nanoparticles and potential applications are discussed. (C) 2007 Elsevier B.V. All rights reserved.