Youlchon Chemical supplies display core material to the Royole foldable phone of China

Youlchon Chemical supplied the core material for a foldable display to the Chinese Royole foldable phone 'Flex Pai'.

According to the industry on May 29, Youlchon Chemical’s silver nanowire (AgNW) has been installed on the organic light-emitting diode (OLED) display of Flex Pie foldable phones made by Royole in China. It is used for the touch screen panel (TSP), and the supply can increase as Royole starts its mass production of folded phones.

For foldable OLEDs of which screen can be folded and unfolded, it is necessary to innovate each material that forms the display window, cover adhesive, optical clear adhesive (OCA), and polarizer. In the case of transparent electrodes for TSP, indium tin oxide (ITO), which is currently used as the main material, can be broken like glass. Thus, graphene, metal mesh, silver nanowire, and the like are attracting attention as an alternative.

Silver nanowire has a mesh structure with a size of several tens of nanometers or less. It is well known as a next-generation transparent electrode material because it transmits electricity and passes light well. However, the surface is rough and the resistance of the section where the silver nanowire overlaps is high. The efficiency was low due to current leakage. In the industry, it has been determined that Youlchon Chemical’s silver nanowire improves the current characteristics by polishing the surface while maintaining the physical properties.

Youlchon Chemical seems to have developed its silver nanowire with its Chinese clients in mind from the outset. China's major smartphone makers such as Xiaomi, Lenovo, and Huawei have selected silver nanowire as transparent electrodes for TSP.

An industry official said, "It is natural for a packaging company to enter the high-value-added electronic materials business to overcome the limitations of the industry. Because Chinese foldable OLEDs are designed with silver nanowires, it is likely that the company aimed at this market."

Youlchon Chemical's electronic materials business turned into a surplus in 2016. It supplied pouch-type battery packaging materials and protective films for OLED panels to the domestic and overseas battery and display companies. Its price competitiveness is higher than competitors including Toray, Nitto Denko, and SKC. Its electronic materials business recorded 21.0bn won, which is more than half of its overall operating profit of 40.3bn won. Adhesive materials, release materials, composite materials, and hard coating materials are the main sources of the revenue.