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Idemitsu awarded the Imperial Invention Prize,the top prize in the 2018 National Commendation for Invention awards
For contributions to the commercialization of television and mobile devices featuring full-color Organic Light-Emitting Diode (OLED) displays

Idemitsu Kosan Co.,Ltd. (Head Office: Chiyoda-ku, Tokyo; Representative Director and CEO: Shunichi Kito; hereinafter, “Idemitsu”) has received the Imperial Invention Prize, which is given to the most outstanding invention, and the Award for Contribution to Invention, at the 2018 National Commendation for Invention awards, for its invention of OLED devices and organic luminescent medium.

[Overview of the winning invention]

Idemitsu’s invention describes a way of realizing pure-blue Organic Light-Emitting Diodes (OLEDs) with practical level luminous efficiency and lifetime, which has greatly contributed to the commercialization of full color OLED displays.
  • OLED materials
    OLED materials
  • Luminescence evaluation of OLED elements
    Luminescence evaluation of OLED elements
OLEDs are comprised of an emitting layer deposited between a pair of opposing electrodes, an anode and cathode. When an electric field is applied between the electrodes, electrons are injected from the cathode and holes are injected from the anode. The electrons recombine with the holes in the emitting layer to produce an excited state complex, and energy is emitted as light when the complex returns to the ground state.

Generally, full-color displays consist of pixels emitting the three primary colors – red, green, and blue. Different OLED materials are needs to generate each of these colors. Blue pixels in a full color OLED display require greater electric power consumption relative to the green and red pixels. Due to this higher power requirement, it was more difficult for blue OLED pixels to achieve long lifetime compared to the red and green ones. This issue was a major hurdle for the use of OLEDs in full-color display devices, such as TVs and smartphones.

Idemitsu’s award-winning invention allowed for functional separation of the role of materials in the OLED that receive energy from electricity, from the role of materials in the OLED that emit light. Through this invention, the color, purity and lifetime characteristics of organic EL light emission in OLEDs were greatly improved.

This breakthrough enabled commercially practical full-color OLED devices by providing commercially viable pixels to generate the last primary color, pure-blue. The invention has contributed greatly to recent development of high-end consumer devices with full-color OLED displays, such as smartphones and TVs.

Award Presented to
Invention Prize
Masahide Matsuura,
Frontier Materials Development Laboratory, Advanced Technology Research
Masakazu Funahashi,
General Manager (Material Development), Electronic Materials Development Center,
Electronic Materials Department
Kenichi Fukuoka,
Director, Customer Support, Idemitsu Electronic Materials Korea Co., Ltd.
Award for
Contribution to
Shunichi Kito,
Representative Director and CEO, Idemitsu Kosan Co.,Ltd.

[The Imperial Invention Prize]

Established in 1919 to contribute to improvements in Japan’s science and technology and to the progress of Japanese industry, the National Commendation for Invention presents awards to commend the contributions of the leading researchers and scientists in Japan. The award ceremony will be held on June 12 at Tokyo.

Idemitsu will continue its contribution to international markets through the introduction of outstanding products and unique technologies, created by its innovative research and development and intellectual property activities.
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