Morphological Control of Linear Particle Deposits from the Drying of Inkjet-Printed Rivulets

We studied the morphology of linear particle deposits obtained by inkjet printing of a silica nanoparticle suspension in drying conditions where contact line depinning occurs. We show that this evaporation mode can be obtained by adjusting the particle concentration in different solvents. For isolated drops, deposited manually or by inkjet printing, drying induces the formation of two concentric rings in which particles self-assemble into a monolayer. For fused drops, our main result is that stable rivulets could be formed by drop overlap leading, after drying, to the formation of three parallel lines composed of a self-assembled particle monolayer. The three lines are of homogeneous thickness with two very thin outer lines (similar to 1 mu m width) and a wider central line (similar to 20 mu m width). We reveal how the width of the resulting lines is influenced by drop spacing in a predictable manner for a large experimental window knowing the drop size.