Pioneer Electronic Corporation

Nippon Kayaku Kabushiki Kaisha

Masanao Shinkai

Takeo Wakimoto

Hitoshi Nakada

Daisaku Matsunaga

Tohru Namiki

Hitoshi Sato

Kenichi Nagayama

Kunio Imai

Ryuji Murayama

Yasuhiko Shirota

Teruichi Watanabe

Disclosed are organic EL elements having high environmental stability as well as high luminous efficiency and luminance. In an organic EL element comprising a transparent anode, a hole-carrying layer, a light-emitting layer and an alloy cathode consisting of a first metal Li and a stabilizing second metal Al, all laminated on a substrate, the concentration of the first metal Li contained in the alloy region with a predetermined thickness from the interface between the alloy cathode and the organic layer is controlled to a minute amount ranging from 0.005 wt. % to 0.3 wt. %. In another organic EL element comprising a transparent anode, a hole-carrying layer, a light-emitting layer and an alloy cathode consisting of a first metal Sr and a stabilizing second metal Mg, all laminated on a substrate, the concentration of the first metal Sr contained in the alloy region with a predetermined thickness from the interface between the alloy cathode and the organic layer (light-emitting layer or electron-carrying layer) is controlled to a minute amount ranging from 10 wt. % to 40 wt. %.

Organic electroluminescent element

An organic EL element comprises a cathode, an EL layer of organic compound, a first hole transport layer of organic compound, a second hole transport layer of organic compound and an anode which are laminated in sequence, wherein the second hole transport layer is made of a substance represented by the following chemical formula 1: ##STR1## where R each independently represents a hydrogen atom, an alkyl group of from 1 to 6 carbon atoms, a halogen group, a cyano group, a nitro group, a primary, secondary or tertiary amino group, or an aryl group of from 6 to 15 carbon atoms. This organic EL element prevents a leakage current and emits light stably for a long time.

Organic electroluminescence element

An electroluminescent device comprising a fluophor luminescent layer and a hole transport layer respectively composed of organic compounds and laminated to each other disposed between a cathode and an anode, said fluophor luminescent layer comprising a pair of fluophor thin films laminated in each other, the material of the cathode-side film having a larger electron transport capacity than the material of the anode-side film.

Electroluminescent device

The electroluminescent element of the present invention comprises a fluorescent substance layer containing a courmarinic or azacoumarinic derivative and a hole transport layer, both made of organic compounds and laminated on top of the other. The both layers are interposed between cathode and anode electrodes. It emits light efficiently at a high luminance upon application of a low voltage between the electrodes.

Electroluminescent element

Disclosed herein is an electroluminescent element which is constructed such that a fluorescent substance layer and a hole transport layer, both made of organic compounds and laminated on top of the other, are interposed between a cathode and an anode. The fluorescent substance layer is a thin film containing a bisstyryl derivative. It emits blue light efficiently at a high luminance upon application of a low voltage.

Growing community of inventors

Saitama, Japan

Masanao Shinkai