Facing the foreseeable short supply of rare metals, efforts to build products without them are spreading across industries. A research group led by Tetsuya Yamamoto, a professor of Kochi University of Technology, developed a technology to build a liquid crystal panel without iridium. The research members developed a new electrode that employs zinc oxide in place of iridium and successfully made the screen thinner and brighter than an iridium-containing panel. Currently, the LCD TV screen uses indium tin oxide (ITO) that is an oxidative product of iridium and tin.
The new technology added the water-shedding function to a zinc oxide film using two kinds of additives elements. The research members operated the trial product in a situation, where temperature is 60 degrees centigrade and humidity is 95%, for 500 hours continuously and confirmed that the new product had the practical level to be used for an electrode of a liquid crystal panel. It has higher light transmission than an ITO-containing electrode besides being energy-saving. LCD TV makers are making strenuous efforts to substitute glass substrate with plastic substrate to make their TVs thinner and lighter. The newly developed zinc oxide electrode is resistant to a small amount of water contained in the film substrate.