Water-based single-walled carbon nanotube (SWCNT) inks with excellent dispersibility for inkjet printed transparent conductive films were prepared by a simple and versatile UV/ozone treatment. The dispersion stability of the SWCNTs was enhanced by the increased oxygen-containing groups on the SWCNT surfaces which were created by the UV/ozone treatment. After inkjet printing of the ink to obtain transparent conductive patterns, circular rings in which most of the SWCNTs are concentrated at the rim were formed by coffee ring effect. The transparent conducting films were achieved by connecting and stacking the rings; the final films inkjet printed in 40 layers have a sheet resistance of 870 Omega sq(-1) at 80% optical transmittance in the wavelength of 550 nm. (C) 2013 Elsevier B.V. All rights reserved.