Roll-to-roll processed silver nanowire/silicon dioxide microsphere composite for high-accuracy flexible touch sensing application

Economical accurate resistive touch sensing panels (TSPs) is fabricated by means of full roll-to-roll (R2R) slot-die coating process. The fabricated TSPs have silver nanowire (Ag NW) random network and uniformly distributed silicone dioxide microspheres (SiO2 MSs) as conducting layer and spacer, respectively. The transparent conductive composite film of Ag NW and SiO2 MSs were R2R coated simultaneously on the flexible substrate, which simplified the manufacturing process. The parametric study was conducted by regulating the diameter and concentration of the SiO2 coating solution. The touch sensing performance was characterized by comparing output images qualitatively and by computing precision and accuracy from output images in response to reference input image. As results, R2R coated SiO2 MSs played a role of space successfully and touch sensing performance was improved with diameter of larger than 1000 nm and concentration of around 1 wt%. Furthermore, multi-functional TSP was fabricated with optimized coating condition and demonstrated to yield various operations in response to touch behavior.