New Printable Ink Electrifies Wearable Technology

A new generation of wearable electronics has landed, and we’ll soon see it in action. Clothing will become smarter, tracking performance data of Olympic contenders, golfers, soccer players and tennis stars. The technology will be embedded in wearable sensors that can help seniors prevent heart failure, manage diabetes and improve quality of life. And in everyday living, it can help anyone more easily track and record important activity data.

You may already own some wearable technology, such as jewelry, badges or shoes that attaches to your body or clothing and provides feedback on your habits. A fitbit, for example, can record your daily steps, calories burned, sleep activity, even heart rate. Thin wires from the tracker relay the information to batteries in your cell phones or other devices.

Taking wearable electronics to a new level are successful studies by the National Research Council of Canada’s (NRC) Advanced Electronics and Photonics (AEP) Research Centre and the Taiwan Textile Research Institute (TTRI). The information they gathered allows manufacturers to embed electronic functionality into garments themselves.

Using electricity-conductive ink to replace wires, the process draws working circuits onto various materials like paper, film or textiles. This eliminates moving parts, and ensures the circuits 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, printable electronics, AEP. “For the past five years, we’ve been working with TTRI on this printing technology to embed electronic function into fabrics and clothing without wires. Dr. George Xiao went to TTRI twice, working side-by-side with our TTRI partners to improve the ink quality.”

This stretchable conductive ink can withstand the 6 main washing tests: twisting, stretching, flexing, extruding, peeling and oxidation. And it can be cleaned with environmentally friendly chemicals, such as ethanol rather than highly toxic toluene or acetone.

The AEP’s intellectual property and TTRI’s manufacturing capacity were a good match for this end-to-end research.

“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, principal research officer, printable electronics, AEP.

He explains 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.

This work by AEP and TTRI was recently awarded a gold-level Edison Award for best new product, one of the highest accolades a company can receive for innovation and business success.

Electrifying the Future

Dr. Chiu, VP of TTRI, points out that stretchable conductive ink has vast potential for product design in the flexible electronics market.

“It is one of the most important core materials that can be combined with other substances for different applications,” he said. “For example, it could be printed on flexible film, display goods or various fabrics such as motion-capture and digital textiles.”

The ink has already been licensed to San Fang Industry Chemical Co., the world’s largest flexible film producer and one of Nike’s top global suppliers.

Dr. Tao adds that the technology also fits into several NRC goals, including the Aging in Place Challenge program. “We can develop products for seniors that help them manage their health issues.” For example, bed linens can be printed with monitors for sleep patterns, breathing rate and more.

The bottom line: this research is right on the money. The flexible electronics market was valued at US$17.99 billion in 2020 and is expected to top US$41.25 billion by 2026. Within that market, the smart clothing sector is set to reach $5.3 billion by 2024, up from $1.6 billion in 2019.

And this is paving the way for partnerships in Canada and beyond to continue innovating and prospering as new generations of technology arise.