Industrial-scale inkjet printed electronics manufacturing—production up-scaling from concept tools to a roll-to-roll pilot line

An efficient strategy for the up-scaling of processing technology for inkjet printing of silver nanoparticle inks towards industrially relevant manufacturing volumes is described. This has been demonstrated by the roll-to-roll production of fine conductive patterns on polymer foils. Starting with small-scale benchmarking to identify the most suitable ink–substrate combination from a range of commercial products, the processing conditions for inkjet printing and sintering were continuously optimized during three consecutive stages. During each iteration, the scale of the experiments in terms of complexity, time requirement and materials usage was increased, thereby more closely resembling the final industrial-scale production conditions. This increased effort was, however, counterbalanced by limiting the number of necessary experiments by purposeful selection based on the results obtained at the lower levels. In addition, the outcome of each previous iteration round served as a starting point for the optimization during the next higher stage. In this way, it was possible to strongly restrict the number of experiments to obtain valuable information about the most ideal conditions at the final stage, which was a roll-to-roll pilot production line. Following this approach, large-area functional conductive structures on plastic foils could be prepared in a continuous manner at process speeds of up to 10 m min–1. These samples showed promising properties for application in printed electronic devices.