Continuous inkjet-patterned and flashlight-sintered strain sensor for in-line off-axis detection in Roll-to-Roll manufacturing

摘要

A thermoresistive strain sensor composed of a meandering resistor and a substrate, and based on Joule heating and infrared (IR) inspection was realized by roll-to-roll (R2R) manufacturing-compatible procedures in this study. Consecutive operations of sensor patterning by inkjet printing, material stabilization by flashlight sintering, thermal generation by Joule heating, and strain evaluation by IR inspection not only successfully demonstrated an in-line strain detection method but also precisely indicated strains distributed in an arbitrary area of a transparent substrate. In this work, a first demonstration proved that the proposed thermoresistive strain sensor and its detection method support evaluations of both symmetric tension and compression to various extents, regardless of the form of power; and a second demonstration proved the effectiveness of the detection method on off-axis or asymmetric substrate deformation that could appear in a R2R system. Besides its tunable sensitivity and gauge factor for operational flexibility, the demonstrated highest sensitivity and the largest gauge factor were 34.49 degrees C per unit strain and 1.25 in the proposed sensor, respectively.