Laser Induced Surface Modification for Inkjet Printing and Coating

Lasers are nowadays widely applied in additive manufacturing and several laser based techniques related to inkjet printing are emerging. In this paper, surface treatment of nanoparticle coatings using a commercial laser engraving machine are presented. Experiments were performed on (i) thin thermally cured silver nanoparticle coatings on glass and (ii) iron oxide (Fe2O3) nanoparticle dispersion coatings on glass. The laser treatment on Ag films illustrates local melting or dewetting behavior dependent on laser power and on the density of engraving patterns. For Fe2O3 coatings, direct laser writing on dried layers and laser treatment on fluid nanoparticle ink layers are investigated. We demonstrate and discuss in particular the generation of large area laser induced microstructures in vertically confined nanoparticle ink films. Controlled ink accumulation is generated by the laser pulses. Furthermore, 2D porous network structures, as well as laser induced large area filament structures are generated by heat driven capillary flow. Tailored adjustments of nanoparticle inks, film thickness and laser treatment patterns open perspectives for the generation of laser induced self-assemblies, e.g. for novel fabrication processes for 2D metamaterials, for sensor developments or advanced anti-counterfeit applications.