Carbon-Based Inks: A Novel Approach to New Technologies

Image courtesy of The Independent.

As large cell phone manufacturers race to create commercially viable and widely adopted folding phones, several major barriers exist, including cost and robust circuitry. Recently, carbon-based conductive inks have been suggested as an alternative for these applications, but either their resistances are too high to be used effectively or they are too expensive. Similarly, graphene-based inks and silver-based inks—currently the most widely used solutions—are extremely costly and impractical to use in commercial products.

A joint group of researchers from Wuhan University and Yale University recently made progress in the development of printable carbon-based inks. The teams have developed a conductive carbon-based ink with both cost-effective production and low internal resistance.

The researchers proposed using a carbon nanotube-based formula to synthesize these highly conductive carbon-based aqueous inks (HCCA-inks). The process to prepare these inks involves hand-mixing an acrylic resin with graphite and carbon black, a substance produced from petroleum. This mixture is then ground and applied to a flexible material. Finally, in tests of the HCCA-inks, the teams bent circuits constructed with the inks and measured the resistance in the circuits. The researchers found that the resistance in the circuits increased modestly as the bending angle increased. In addition to these advantages, Yu Liao, one of the researchers who worked in the development of the HCCA-ink, described the HCCA-ink formula as having a “higher mechanical strength” as well as being “easier to industrialize” than the current industry standard inks.

These carbon-based inks may have applications beyond the commercial technology industry. For example, Liao stated, “We want to use our ink in more printed electronic products, to help more students.”