Electronic textiles (e‐textiles) that combine the wearing comfort of textiles and the functionality of soft electronics are highly demanded in wearable applications. However, fabricating robust high‐performance stretchable e‐textiles with good abrasion resistance and high‐resolution aesthetic patterns for high‐throughput manufacturing and practical applications remains challenging. Herein, the authors report a new multifunctional e‐textile fabricated via screen printing of the water‐based silver fractal dendrites conductive ink. The as‐fabricated e‐textiles spray‐coated with the invisible waterproofing agent exhibit superior flexibility, water resistance, wearing comfort, air permeability, and abrasion resistance, achieving a low sheet resistance of 0.088 Ω sq−1, high stretchability of up to 154%, and excellent dynamic stability for over 1000 cyclic testing (ε = 100%). The printed e‐textiles can be explored as strain sensors and ultralow voltage‐driven Joule heaters driven for personalized thermal management. They finally demonstrate an integrated aesthetic smart clothing made of their multifunctional e‐textiles for human motion detection and body‐temperature management. The printed e‐textiles provide new opportunities for developing novel wearable electronics and smart clothing for future commercial applications.
This study introduces a high‐throughput, large‐scale manufacturing method that uses aerosol jet 3D printing for a fully printed stretchable, wireless electronics. A comprehensive study of nanoink preparation and parameter optimization enables a low‐profile, multilayer printing of a high‐performance, capacitance flow sensor. The core printing process involves direct, microstructured patterning of biocompatible silver nanoparticles and polyimide. The optimized fabrication approach allows for transfer of highly conductive, patterned silver nanoparticle films to a soft elastomeric substrate. Stretchable mechanics modeling and seamless integration with an implantable stent display a highly stretchable and flexible sensor, deployable by a catheter for extremely low‐profile, conformal insertion in a blood vessel. Optimization of a transient, wireless inductive coupling method allows for wireless detection of biomimetic cerebral aneurysm hemodynamics with the maximum readout distance of 6 cm through meat. In vitro demonstrations include wireless monitoring of flow rates (0.05–1 m s−1) in highly contoured and narrow human neurovascular models. Collectively, this work shows the potential of the printed biosystem to offer a high throughput, additive manufacturing of stretchable electronics with advances toward batteryless, real‐time wireless monitoring of cerebral aneurysm hemodynamics.
more » « less- NSF-PAR ID:
- 10461220
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 6
- Issue:
- 18
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Recent developments in stretchable electronics hold promise to advance wearable technologies for health monitoring. Emerging techniques allow soft materials to serve as substrates and packaging for electronics, enabling devices to comply with and conform to the body, unlike conventional rigid electronics. However, few stretchable electronic devices achieve the high integration densities that are possible using conventional substrates, such as printed rigid or flexible circuit boards. Here, a new manufacturing method is presented for wearable soft health monitoring devices with high integration densities. It is shown how to fabricate soft electronics on rigid carrier substrates using microfabrication techniques in tandem with strain relief features. Together, these make it possible to integrate a large variety of surface mount components in complex stretchable circuits on thin polymer substrates. The method is largely compatible with existing industrial manufacturing processes. The promise of these methods is demonstrated by realizing skin‐interfaced devices for multimodal physiological data capture via multiwavelength optoelectronic sensor arrays comprised of light emitting diodes and phototransistors. The devices provide high signal‐to‐noise ratio measurements of peripheral hemodynamics, illustrating the promise of soft electronics for wearable health monitoring applications.
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