This invention introduces silver-copper (AgCu) nanoalloy inks and pastes that sinter at room temperature, enabling low-cost, flexible, and energy-efficient printed electronics. The formulation maintains high conductivity, resists oxidation, and can be printed on heat-sensitive substrates like paper, polymers, and textiles without external heating, supporting scalable manufacturing of flexible electronic devices.
Background: The growth of printed and flexible electronics is limited by the cost and processing demands of existing conductive inks. Silver-based inks offer excellent conductivity but require high sintering temperatures and remain prohibitively expensive for large-scale use. Copper and carbon alternatives are less stable, suffering from oxidation and reduced conductivity. These issues prevent printing on temperature-sensitive materials such as paper, textiles, and polymer films. A conductive ink that combines high performance, low cost, and room-temperature processability is needed to unlock the full potential of flexible and sustainable electronic manufacturing.
Technology Overview: This invention features a novel silver-copper (AgCu) nanoalloy ink and paste formulation capable of sintering at ambient temperature. The nanoparticles, synthesized via a scalable wet-chemical reduction process, exhibit a uniform face-centered cubic (fcc) alloy structure—unlike typical core-shell systems—providing intrinsic conductivity and oxidation resistance. The dispersion remains stable and printable across multiple methods, including inkjet, aerosol jet, and screen printing. Under ambient humidity, the particles undergo natural sintering to form conductive films without thermal or photonic curing. This approach enables low-cost, flexible, and energy-efficient electronic patterning on diverse substrates such as PET, paper, and fabric.
Advantages: • Enables room-temperature sintering on heat-sensitive substrates • Reduces material cost through silver-copper alloy composition • Improves oxidation resistance versus pure copper inks • Maintains high electrical conductivity without high-temperature curing • Supports scalable, composition-controlled synthesis for mass production • Allows printing on flexible and unconventional materials such as paper and textiles • Eliminates need for photonic or thermal post-processing equipment • Uses ambient humidity for sintering, minimizing energy and equipment costs
Applications: • Printed and flexible electronics on heat-sensitive substrates • Wearable and medical sensors printed directly on fabrics or polymers • Paper-based environmental monitoring and disposable sensing devices • Conductive busbars and interconnects for flexible solar panels • Low-cost antennas and RFID tags for smart packaging and logistics
Intellectual Property Summary: • United States – 63/460,162 – Provisional – Filed 04/18/2023 – Converted • United States – 18/630,630 – Utility – Filed 04/09/2024 – Status: Filed
Stage of Development: Prototype validated on multiple substrates and print methods (PET, paper, textiles; inkjet, aerosol jet, screen printing).
Licensing Status: This technology is available for licensing.
Licensing Potential: Highly relevant to manufacturers of printed electronics, wearable sensors, and smart packaging seeking low-cost, energy-efficient conductive ink solutions for flexible and heat-sensitive substrates.
Additional Information: Detailed conductivity measurements, humidity-dependent sintering behavior, and mechanical flexibility data available upon request.
Inventors: Richard Robinson, Guojun Shang, Shan Wang, Shan Yan, Chuan Jian Zhong