Title:
BLUE LIGHT EMITTING ELEMENT
Document Type and Number:
Japanese Patent JP3555271
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain a long-life organic electroluminescent (EL) element which emits blue light, is driven at a low voltage and has high luminance by doping with a specified coumarin derivative.
SOLUTION: The coumarin derivative used comprises one represented by the formula (wherein R1 to R4 are each H or an alkoxy and, when adjacent to one another, they allow substituted or unsubstituted benzene rings to condense; and X is phenyl, benzothiazolyl, benzoxazolyl or benzimidazolyl). The EL element has substantially a constitution wherein the coumarin derivative, a hole transfer material (e.g. polyvinyl carbazole) and an electron transfer material (e.g. a polymer compound having an electron-transfer capability) are inserted between a pair of electrodes and, if necessary, a hole transfer layer and an electron transfer layer are put therebetween. The amount of the coumarin derivative added is 0.1-5wt.% based on the total of the hole transfer material and the electron transfer material. The organic layer used is obtained by dissolving the coumarin derivative in a solvent and forming a thin film from the solution by, e.g. spin coating.
Inventors:
Manabu Uchida
Yusho Izumisawa
Kenji Furukawa
Yusho Izumisawa
Kenji Furukawa
Application Number:
JP23195295A
Publication Date:
August 18, 2004
Filing Date:
August 16, 1995
Export Citation:
Assignee:
Chisso Co., Ltd.
International Classes:
H05B33/22; C09K11/06; H01L51/50; H05B33/12; H05B33/14; (IPC1-7): H05B33/22; C09K11/06; H05B33/14
Domestic Patent References:
| JP2191694A | ||||
| JP7157753A | ||||
| JP6122874A | ||||
| JP6073373A | ||||
| JP3000792A | ||||
| JP4212286A |