The unusual rise in silver prices in the current commodity price environment is causing unrest - but in contrast to speculative purchases by rebellious small investors and strategic short selling of shares by professional hedge funds ('Gamestop'), which have led to outright turmoil on the US stock markets. The silver price surge could also trigger a surge in innovation in the field of conductive inks for printed electronics. This is the conclusion reached by the British market researcher and conference organizer IDTechEx.
He explains more in his latest press release from February 2, 2021: At the beginning of February 2021, the price of silver reached a new high of 950 US dollars per kg in the first half of the year. This affects the electronics industry, especially industrial users of silver materials in the form of conductive inks. In their recently published market study 'Conductive Ink Markets 2020-2030: Forecasts, Technologies, Players', IDTechEx authors Matthew Dyson and Yasuo Yamamoto break down the numerous suppliers and fields of application for these conductive inks: Photovoltaics, 5G Mobilfuk, Automotive, Power Electronics, EMI Shielding, In-Mold Electronics, e-Textiles, Medical Patches, Printed Sensors, Flexible Hybrid Electronics, RFID, 3D Metallization, Heaters, etc....
They estimate silver's share of the current global market for conductive inks at 2.3 billion dollars annually. The largest share is in inks for the connection fingers of busbars on solar panels. This shows its decisive role in the generation and application of sustainable energy. Silver is also an essential material in printed electronics, for example in pressure sensors and medical plasters.
According to IDTechEx, the established use of conductive inks is in the form of silver flakes just a few microns in diameter. They are embedded in various polymer-based binder materials to achieve the appropriate rheology for the application. According to the authors of the study, silver accounts for at least 80 percent of the cost of the conductive inks produced. This makes them highly sensitive to fluctuations in the price of the base material, especially if they are triggered by speculative actions outside the industry.
If silver prices continue to rise, IDTechEx concludes, this would require changes in the composition of conductive inks. The most promising trend would be the transition to copper-based inks. At currently around 8 dollars per kg, copper is more than a hundred times cheaper than silver. Actually, copper has always been attractive in this context, but technically it is a challenge, mainly because it reacts much more strongly with the environment and oxidizes quickly in air in the form of copper oxide.
The remedies used to date to combat copper oxidation, such as silver-coated copper nanoparticles and printing in an inert atmosphere, have proved to be impractical because they increase costs and are not sufficiently durable. Recently, processes such as the addition of additives, which act as a reduction agent during sintering, have proven their worth.
Another transition at IDTechEx is the replacement of flakes with nanoparticles as the basis for conductive inks and completely particle-free alternatives. Both developments show a higher conductivity of up to 80 percent compared to pure silver. Of course, such inks would be considerably more expensive due to the greater complexity of their manufacturing process. On the other hand, the silver content of these alternative formulations would be lower, reducing their dependence on fluctuations in raw material prices. They would therefore be an innovation worth considering.
