Fabrication of flexible strain sensors via roll-to-roll gravure printing of silver ink

We fabricated flexible printed strain sensors by roll-to-roll (R2R) gravure printing of the silver paste on polyimide substrate. The printed sensors with size 10 x 17 mm(2) were sintered at high temperature to obtain stable resistance value. The fabricated sensor was attached onto the plastic bar and the strain measurement was performed under bending, tensile, and periodic loadings. The strain sensors showed the gauge factor of 1.99-2.24 and the measurable strain range of -386 x 10(-6) to 16 272 x 10(-6). It is comparable to that of the commercially available strain gauges and excellent when compared to the previous studies. The R2R-based strain sensor fabrication is expected to be used not only for manufacturing innovation of existing commercial sensors but also for resistor-based emerging wearable devices.