Japan is an important supplier of upstream OLED materials. Sumitomo Chemical and Showa Denko are the main material producers of polymer-based OLED, and Idemitsu Kosan and Mitsui Chemicals...
South Korea's LED supply chain relies on Japan's Kyocera and Namiki for sapphire substrates, and Nichia and Toyoda Gosei for epitaxial wafers, chip packaging and LED phosphor mater...