System Design and Process Optimization for the Inkjet Printing of PEDOT:Poly(styrenesulfonate)
Abstract
A laboratoryscale inkjet printing system was designed for printing polymeric inks with the focus on PEDOT:PSS, a transparent, electrically conductive polymer. PEDOT:PSS inks with 0 and 1 wt. % Surfynol were tested rheologically in elongational and shear flows. A process model is presented and validated for the prediction of flow boundary after the ink exits the nozzle, including drop formation. Process optimization involved establishing a process window related to the voltage waveform, substrate temperature, speed and printed lineoverlap, aiming at avoiding satellite drops, “coffee cup†rings, the Rayleigh instability, “stacked printed lines,†and discontinuities in the printed lines or films.