Organic and Metallic Sensors on Complex 3-D Object Using an Original Method: Water Transfer Printing

International audienceSensors need to intimately wrap objects that we want to monitor, track, or supervise. By way of example, adding a strain gauge, some temperature or humidity sensors directly on 3-D objects, leads to improved structural health monitoring, protects materials from overheating, and sustaining a comfortable humidity level. In this letter, we present a conformal and substrate-free transfer of sensors to complex 3-D objects using water transfer printing (WTP) concept. Herein, the sensors are screen-printed using carbon and silver inks. To determine if the WTP process affects sensors performances, we compare the sensitivities obtained from transferred sensors with those directly screen-printed on polyethylene terephthalate (PET) substrate. Three types of sensors are studied to highlight WTP capabilities, paving the way for multisensor platforms. Obtained results highlight that transferred carbon strain gauges are more sensitive than screen-printed sensors. Therefore, their corresponding linear gauge factors were calculated as 18 and 15, respectively. Temperature sensitivity of carbon and silver-based sensors increases after WTP process. For silver temperature sensors, the corresponding sensitivities are 0.24%/°C for the screen-printed sensor and 0.28%/°C for the transferred one. Moreover, the WTP process demonstrated no significant impact on the transfer of carbon humidity sensor. © 2017 IEEE