Idemitsu Kosan Company, Limited

Idemistu Kosan Co., Ltd.

Hisahiro Higashi

Chishio Hosokawa

Tadashi Kusumoto

Toshio Sakai

Hiroshi Tokailin

Hiroaki Nakamura

Kenichi Fukuoka

Hidetsugu Ikeda

Hisayuki Kawamura

Masahide Matsuura

Kiyoshi Ikeda

An organic electroluminescence device comprising a pair of electrodes and a layer of an organic light emitting medium disposed between the pair of electrodes, wherein the layer of an organic light emitting medium comprises a mixed layer comprising (A) at least one hole transporting compound and (B) at least one electron transporting compound, an energy gap of the hole transporting compound represented by Eg1 and an energy gap of the electron transporting compound represented by Eg2 satisfy a relation: Eg1&#x3c;Eg2. Electrons and holes are recombined in the layer of an organic light emitting medium and light is emitted. The organic electroluminescence device has a long life and emits light at a high efficiency.

Organic electroluminescence device

The invention is an organic electroluminescent device that comprises organic compound layer(s) including at least one organic emitting layer sandwiched between a pair of electrodes, wherein at least one organic compound layer is formed from an organic compound material having an impurity concentration of lower than 1000 ppm. The device has the advantages of applicability to lightweight, thin and low-voltage driving displays, good luminescent capacity attenuating little even in long-term driving operation, and good durability.

Organic electroluminescence device with organic compound layer containing lower than 500 PPM of a halogen-containing compound

The invention provides an organic EL device which produces high luminance and is durable and which can be fabricated with ease. The organic EL device comprises two electrodes and a light-emitting layer sandwiched therebetween, in which the light-emitting layer contains a molecular compound having an electron-transporting unit and a hole-transporting unit bonded to each other via a linking group.

Organic electroluminescent device

An organic electroluminescence device which exhibits excellent heat resistance, a long life and a high efficiency and emits bluish light and an organic light emitting medium advantageously used for the organic electroluminescence device. The organic electroluminescence device comprises a layer of an organic light emitting medium which is disposed between a pair of electrodes and comprises (A) a mono-, di-, tri- or tetrastyryl derivative containing amine and (B) an anthracene derivative having a specific structure. The organic light emitting medium comprises components (A) and (B).

Organic electroluminescence device and organic light emitting medium

The present invention relates to a practical organic EL element which is excellent in a durability without decreasing a luminance even in the driving for a long period of time and which is appropriately used in, for example, a display of information appliances or the like, a process for producing the same, and further an organic EL film. It is an organic electroluminescence element in which an organic compound layer having at least an organic emitting layer is held between a pair of electrodes, an anode and a cathode, an intensity of a main peak and an intensity of each sub-peak in a mass spectrum of at least one layer of the organic compound layer satisfying a specific relationship.

Organic electroluminescence device and method of its manufacture

Disclosed is a practical, organic, blue-emitting EL device having a long life and having high luminous efficiency and good thermal stability. The device comprises organic compound layers, of which at least one is an organic blue-emitting layer, as sandwiched between a pair of electrodes, and is characterized in that the organic blue-emitting layer comprises an organic host compound having a fluorescence quantum efficiency of not smaller than 0.3 in a solid state and a fluorescent substance, and the organic host compound and the fluorescent substance are selected such that the device retains a monomeric blue-emitting ability, and that all the organic compound layers have a glass transition temperature of not lower than 75&deg; C., while the organic compound layers adjacent to the organic blue-emitting layer have a glass transition temperature of not lower than 105&deg; C.

An organic EL device comprising a plurality of organic compound layers that include at least two or more organic light-emitting layers and are sandwiched between a pair of electrodes of anode and cathode, wherein two or more of these organic light-emitting layers are all doped with a fluorescent substance of the same type or the same color that constitutes the organic light-emitting layers. The device has a long life and high light-emitting efficiency.

A practical, organic, blue-emitting EL device having a long life and having high luminous efficiency and good thermal stability. The device comprises organic compound layers, of which at least one is an organic blue-emitting layer, as sandwiched between a pair of electrodes, and is characterized in that the organic blue-emitting layer comprises an organic host compound having a fluorescence quantum efficiency of not smaller than 0.3 in a solid state and a fluorescent substance, and the organic host compound and the fluorescent substance are selected such that the device retains a monomeric blue-emitting ability, and that all the organic compound layers have a glass transition temperature of not lower than 75&deg; C., while the organic compound layers adjacent to the organic blue-emitting layer have a glass transition temperature of not lower than 105&deg; C.

An aromatic dimethylidyne compound of the formula: ##STR1## wherein X and Y are the same or different and are each an alkyl having 1 to 4 carbons, a phenyl, a cyclohexyl, a naphthyl, or a pyridyl and Ar' is ##STR2## A process for preparing an aromatic dimethylidyne compound which comprises condensing a phosphorus compound and a ketone compound.

Aromatic dimethylidyne compounds

A thin film electroluminescence device and a process for production thereof. This device is characterized in that as a light emitting layer material or charge injection layer material, a polymer film having at least one of a light emitting layer function, a charge transport function and a charge injection function, and having a film thickness of not: more than 0.5 .mu.m is prepared by the vacuum evaporation method and used.

Thin film electroluminescence device

Charge injection auxiliary material and organic electroluminescence

An organic electroluminescence device comprises the first light emitting layer containing an organic compound having a fluorescence peak wave length of 380 nm or longer to shorter than 480 nm in solid state and the second light emitting layer containing an organic compound having a fluorescence peak wave length of 480 nm or longer to shorter than 580 nm in solid state. One of the first light emitting layer and the second light emitting layer contains an organic compound having a fluorescence peak wave length of 580 nm or longer to 650 nm or shorter in solution state. The device has a structure in which the first light emitting layer and the second light emitting layer are laminated on the anode in this order and both of these layers emit light by application of an electric field. This device shows light emission, particularly white light emission, with high efficiency and excellent stability.

A thin film electroluminescence device and a process for production thereof. This device is characterized in that as a light emitting layer material or charge injection layer material, a polymer film having at least one of a light emitting layer function, a charge transport function and a charge injection function, and having a film thickness of not more than 0.5 .mu.m is prepared by the vacuum evaporation method and used.

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Sodegaura, Japan

Hisahiro Higashi