The deposition behaviour of uniformly sized silica particles in drying aqueous droplets has been investigated for a range of particle sizes, 0.33, 1, 3 and 5 mm, in order to gain an improved understanding of the coffee drop effect. The droplets were produced by inkjet printing, which allowed multiple droplets of similar volume to be studied. Our observations show that particle size and the contact angle formed by the solvent droplet with the substrate determine how close to the boundary a particle is deposited. After drying, it was found that if the contact angle was less than 90 , smaller particles were located closer to the original droplet's periphery than larger particles in similar sized droplets. This deposition of particles can be explained by the wedge shape of the drying droplet's edge, which physically limits the movement of particles towards the droplet's periphery. In this paper we show that the size of a suspended particle influences the final dried morphology of a printed feature.

Hot‐embossed features are prepared by pushing customized and standard silicon calibration gratings, known as masters, into either polystyrene or polycarbonate, which are kept above their glass transition temperatures. droplet of a silver nanoparticle ink is then dispensed over one of these as‐formed grooves using an inkjet printer. The ink fills the grooves as a consequence of capillary forces and is observed to form tracks with a uniform width. The tracks are described as ‘invisible’ on account of having widths ranging from 5 to 15 µm. Wider tracks can be produced by dispensing more droplets and tracks with different morphologies can be produced by using different masters. Several as‐prepared features are thermally treated to produce conductive silver tracks. The conductivity of the tracks is found to be ∼20% that of bulk silver.

The fabrication of a poly(3,4-ethylenedioxythiophene) (PEDOT) pattern is demonstrated. As template, an n-octadecyltrichlorosilane (OTS) monolayer self-assembled on indium tin oxide (ITO) was structured by UV-ozone photolithography, resulting in an ITO-OTS patterned surface. The conducting properties of the ITO were utilized for the selective electropolymerization of 3,4-ethylenedioxythiophene (EDOT), whereby the electropolymerization was inhibited by the insulating OTS. Differently sized PEDOT-OTS patterns were obtained. The electronic properties of the patterns were finally evaluated in a test OLED device.