Paper-Embedded Roll-to-Roll Mass Printed Piezoelectric Transducers.

The trend to a world with ubiquitous electronics has the need for novel concepts for sensors and actuators that are lightweight, flexible, low-cost, and also sustainable. Piezoelectric transducers on the basis of functional polymers can meet these expectations. In this work, a novel concept for paper-embedded large-area piezoelectric devices realized solely by means of roll-to-roll (R2R) mass printing and post printing technologies including inline poling are introduced. The device set-up, as well as the process technology, offers the great opportunity for a cost-efficient and environmentally friendly mass production of thin and flexible organic large-area piezoelectric devices. As the functional layers are embedded into paper by the hot lamination of two poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TrFE) layers, the printed electronics is protected and invisible. The paper gives insights to the R2R printing of a 500 m long web including R2R post printing processes and electrical and acoustic inline characterization. Fully R2R processed devices show a high remnant polarization of up to 78 mC m-2 and can be realized with high yield of >90%. Finally, a 360° surround-sound installation realized with a 387 cm long paper web consisting of 56 piezoelectric speakers including wiring is presented.