Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo

Kojiro Tachi

Masahiko Ishii

Yasunori Taga

Hisayoshi Fujikawa

Koji Noda

Sadaharu Suga

Makoto Satsuki

Kazushige Kojima

Makoto Fujiwara

Natsuko Ishida

This invention has an objective to improve durability at elevated temperature in organic electroluminescent devices using coumarin derivatives as dopant in a luminescent layer. This invention attains the above objective by providing in the organic electroluminescent devices formed by laminating an anode, a hole injection layer, a hole transportation layer, a luminescent layer, an electron transportation layer and a cathode in this order, the luminescent layer which comprises as dopant the green light-emitting coumarin derivative and hole- and electron-transporting substances as host; said coumarin derivative consisting of a plurality of coumarin groups bound to an aromatic ring, heterocycle, or any combination thereof, and exhibiting a glass transition point of 150&#xb0; C. or higher or a melting point of 297&#xb0; C. or higher.

Organic electroluminescent device

Growing community of inventors

Aichi, Japan

Kojiro Tachi