World famous Idemitsu blue
History of Idemitsu Blue
In search of the impossible blue light
In 1985, Idemitsu Kosan began researching OLED materials. The company was exploring the possibility of a new business venture that went beyond the boundaries of its existing petroleum and petrochemical businesses, and its development target was a blue luminescent material, which was considered the most difficult of the three primary colors of light (red, blue, and green) to put into practical use. At the time, "inorganic" semiconductors were the electronic materials that were attracting the most attention. The development of organic luminescent materials was still uncertain.
Four years after starting development, the research team discovered a fluorescent material called "distyrylarylene" that emits a blue light that is noticeable even in bright places. This was a groundbreaking achievement, as blue light was not yet achievable even with inorganic semiconductors at the time. In 1997, they discovered a blue dopant called "styrylamine" that significantly improved light output and lifespan. They continued to develop technology to extend lifespan and increase efficiency, and finally succeeded in developing a blue luminescent material.
In 1997, our company exhibited the world's first OLED television at the International Display Society held in the United States, which attracted a great deal of attention from around the world.
Selected as the best paper of "Display Week 2022" for development of new light emission method
Our company continues to take on new challenges, and has developed a new light-emitting method using stacked light-emitting layers in fluorescent blue OLED element, successfully achieving the world's highest level of luminous efficiency and long life. This result was selected as the best paper at the symposium "Display Week 2022" hosted by the Society of Information Display.
A long-standing challenge for OLED has been the "law of trade-off between lifespan and efficiency," meaning that efficiency decreases as lifespan is extended. The research team felt the need to develop technology that would overturn regulatory concepts, rather than simply being an extension of existing technology, and they created new structural concepts and ideas, steadily repeating experiments to test each of the materials used in past research and development. The strengths of our company, such as our high level of intellectual property and the teamwork of our research team, worked synergistically, and we succeeded in creating a method to reduce luminous loss by separating the layers of two types of blue material, achieving both high luminous efficiency and long lifespan.
This technology simultaneously achieves improved luminous efficiency and longer life compared to conventional technologies, contributing to further power savings in OLED displays and reducing the environmental burden by improving product lifecycles.