The ink, which is washable and can be used in place of wires, could herald the next generation of wearables, the researchers said.
The ink was through a collaboration between the National Research Council of Canada's (NRC) Advanced Electronics and Photonics (AEP) Research Centre and the Taiwan Textile Research Institute (TTRI).
According to the researchers, the ink could allow manufacturers to embed electronic functionality clothing. By using conductive ink to replace wires, moving parts are eliminated, and the circuits can survive unlimited washing.
"Most inks now on the market are not stretchable, so when washed they can become brittle and lose conductivity," said Dr Ye Tao, team lead for printable electronics at AEP. "For the past 5 years, we've been working with TTRI on this printing technology to embed electronic function into fabrics and clothing without wires."
The stretchable conductive ink can withstand the six main washing tests – twisting, stretching, flexing, extruding, peeling and oxidation – and can be cleaned with environmentally friendly chemicals, such as ethanol rather than highly toxic toluene or acetone.
The five-year research project relied on AEP's intellectual property and TTRI's manufacturing capacity. "We own the patent for the ink, while TTRI provides the means for developing applications," said Dr George Xiao, the first inventor of the patent and the principal research officer for printable electronics at AEP.
Xiao said that he and his team created the ink in small quantities in the lab, then sent the formula to TTRI for large-quantity testing. This determined shelf life, stabilization, stretchability requirements and other factors important to the industry.