Electronic textiles (e‐textiles) are in prime position to revolutionize the field of wearable electronics owing to their ubiquitous use and universal acceptance. However, mechanical incompatibility between the rigid conductive components on the soft textile platforms creates fragile e‐textile systems with poor electromechanical attributes. In this work, a novel design strategy to inkjet print reactive silver inks onto woven textiles with Kirigami‐inspired patterning to create e‐textiles with enhanced electromechanical features is introduced. By controlling the print processing and curing conditions, uniform conductive coatings with sheet resistances of 0.09 Ω sq−1 are achieved such that they do not interfere with the textiles innate flexibility, breathability, comfort, and fabric hand. The electromechanical coupling of the printed textiles shows a direct dependence on the anisotropic nature of the woven structures. Introducing Kirigami patterning creates robust devices that enhance and stabilize the electrical conductivity (ΔR/R0 < −20%) over large strain regimes (>150%). Furthermore, an electrocardiogram monitoring system fabricated from Kirigami e‐textiles exhibits stable signal acquisition under extreme deformations from arm joint flexion. The distinct properties of Kirigami patterning on e‐textiles enable unprecedented electromechanical performance in wearable textile electronics.

Soft printed electronics exhibit unique structures and flexibilities suited for a plethora of wearable applications. However, forming scalable, reliable multilayered electronic devices with heterogeneous material interfaces on soft substrates, especially on porous and anisotropic structures, is highly challenging. In this study, we demonstrate an all-inkjet-printed textile capacitor using a multilayered structure of bilayer polymer dielectrics and particle-free metal−organic decomposition (MOD) silver electrodes. Understanding the inherent porous/anisotropic microstructure of textiles and their surface energy relationship was an important process step for successful planarization. The MOD silver ink formed a foundational conductive layer through the uniform encapsulation of individual fibers without blocking fiber interstices. Urethane-acrylate and poly(4-vinylphenol)-based bilayers were able to form a planarized dielectric layer on polyethylene terephthalate textiles. A unique chemical interaction at the interfaces of bilayer dielectrics performed a significant role in insulating porous textile substrates resulting in high chemical and mechanical durability. In this work, we demonstrate how textiles' unique microstructures and bilayer dielectric layer designs benefit reliability and scalability in the inkjet process as well as the use in wearable electronics with electromechanical performance.

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Pressure sensors for wearable healthcare devices, particularly force sensitive resistors (FSRs) are widely used to monitor physiological signals and human motions. However, current FSRs are not suitable for integration into wearable platforms. This work presents a novel technique for developing textile FSRs (TFSRs) using a combination of inkjet printing of metal-organic decomposition silver inks and heat pressing for facile integration into textiles. The insulating void by a thermoplastic polyurethane (TPU) membrane between the top and bottom textile electrodes creates an architectured piezoresistive structure. The structure functions as a simple logic switch where under a threshold pressure the electrodes make contact to create conductive paths (on-state) and without pressure return to the prior insulated condition (off-state). The TFSR can be controlled by arranging the number of layers and hole diameters of the TPU spacer to specify a wide range of activation pressures from 4.9 kPa to 7.1 MPa. For a use-case scenario in wearable healthcare technologies, the TFSR connected with a readout circuit and a mobile app shows highly stable signal acquisition from finger movement. According to the on/off state of the TFSR with LED bulbs by different weights, it can be utilized as a textile switch showing tactile feedback.

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