Electrically conductive structures comprising both narrow line widths and high aspect ratios are indispensable components of many electronic devices. Producing them reliably on an industrial scale by inkjet printing of metal-based inks is a serious challenge. Firstly, due to spreading of the ink on the substrate, widths of 30 microns are currently the limit of any standard industrial inkjet technology. Secondly, the solid loads of conductive inkjet fluids are usually confined to a low volume fraction. Consequently, fine and high conductive structures are difficult to reach with single pass printing approaches.Here we report on a method which circumvents these limits by employing specific changes in the ink-substrate interactions during solvent evaporation. Freshly printed lines have widths in the order of 100 microns. Upon drying, these structures reproducibly shrink to very narrow (< 25 micron), though still continuous and highly conductive lines with heights of several microns. This results in aspect ratios of up to 0.3, which are unprecedented for single pass inkjet printing.We propose a mechanism for this process which involves the sequential evaporation of the ink's solvents according to their vapour pressures. Since their volatilities correspond inversely with their respective polarities, the effective polarity of the material remaining on the substrate will continuously increase. A continuous movement out of the wetting envelope of the substrate is the logical consequence, resulting in ever poorer wetting, increasing contact angles and line shrinkage.