Optimal Design of Pneumatic Flotation for Roll-to-Roll Conveyance in the Production of Printed Circuits

Flexible printed electronic circuits have recently attracted attention as an alternative promising methodology due to the additive process being more environmentally friendly and using less raw material compared to conventional lithography and chemical vapor deposition. However, printed circuits produced by roll-to-roll (R2R) conveyance are often scratched, which can result in breaks in the conductive tracks, cracks, or pinholes. This study investigated a proposed optimal design for an air bar for use in an R2R printing system. The optimal distance between the roll surface and floating substrate for preventing scratching of the printed circuit was investigated. The optimal design-including the blower frequency, size of air holes, and density of air holes-was investigated using simulations of fluid-structure interactions for estimating substrate behavior during pneumatic flotation. The distribution of air pressure in the space between the substrate and the surface of the air bar was calculated, and the deformation of the substrate by the air pressure was analyzed. The optimal design of the air bar was verified in numerical simulations and experiments using various conditions.