Abstract: Provided is a practically useful organic electroluminescent device (organic EL device) having high efficiency and high driving stability while being capable of being driven at a low voltage. The organic electroluminescent device includes a light-emitting layer between an anode and a cathode opposite to each other. The light-emitting layer contains two host materials and at least one light-emitting dopant. One of the two host materials is a host material selected from an indolocarbazole compound having one indolocarbazole ring and an indolocarbazole compound having two indolocarbazole rings, and the other thereof is a host material selected from carbazole compounds.

Abstract: Provided is a practically useful organic electroluminescent device (organic EL device) having high efficiency and high driving stability while being capable of being driven at a low voltage. The organic electroluminescent device includes a light-emitting layer between an anode and a cathode opposite to each other. The light-emitting layer contains two host materials and at least one light-emitting dopant. One of the two host materials is a host material selected from an indolocarbazole compound having one indolocarbazole ring and an indolocarbazole compound having two indolocarbazole rings, and the other thereof is a host material selected from carbazole compounds.

Abstract: Provided are a hole-injecting material for an organic electroluminescent device (organic EL device) exhibiting high luminous efficiency at a low voltage and having greatly improved driving stability, and an organic EL device using the material. The hole-injecting material for an organic EL device is selected from benzenehexacarboxylic acid anhydrides, benzenehexacarboxylic acid imides, or N-substituted benzenehexacarboxylic acid imides. Further, the organic EL device has at least one light-emitting layer and at least one hole-injecting layer between an anode and a cathode arranged opposite to each other, and includes the above-mentioned hole-injecting material for an organic EL device in the hole-injecting layer. The organic EL device may contain a hole-transporting material having an ionization potential (IP) of 6.0 eV or less in the hole-injecting layer or a layer adjacent to the hole-injecting layer.

Abstract: Disclosed is an organic electroluminescent device (organic EL device) which can achieve high efficiency and long lifetime even when driven at low voltage. The organic El device comprises at least a light-emitting layer and an electron-transporting layer between an anode and a cathode facing each other. The electron-transporting layer consists of two layers, namely, a first electron-transporting layer and a second electron-transporting layer and the first electron-transporting layer and the second electron-transporting layer are arranged sequentially in this order from the light-emitting layer side to the cathode side. The first electron-transporting layer contains an indole derivative in which the ring nitrogen atom is substituted with an aromatic group and an aromatic ring is fused to the indole ring.

Abstract: Provided are a hole-injecting material for an organic electroluminescent device (organic EL device) exhibiting high luminous efficiency at a low voltage and having greatly improved driving stability, and an organic EL device using the material. The hole-injecting material for an organic EL device is selected from benzenehexacarboxylic acid anhydrides, benzenehexacarboxylic acid imides, or N-substituted benzenehexacarboxylic acid imides. Further, the organic EL device has at least one light-emitting layer and at least one hole-injecting layer between an anode and a cathode arranged opposite to each other, and includes the above-mentioned hole-injecting material for an organic EL device in the hole-injecting layer. The organic EL device may contain a hole-transporting material having an ionization potential (IP) of 6.0 eV or less in the hole-injecting layer or a layer adjacent to the hole-injecting layer.

Abstract: Disclosed is an organic electroluminescent device (organic EL device) which can achieve high efficiency and long lifetime even when driven at low voltage. The organic El device comprises at least a light-emitting layer and an electron-transporting layer between an anode and a cathode facing each other. The electron-transporting layer consists of two layers, namely, a first electron-transporting layer and a second electron-transporting layer and the first electron-transporting layer and the second electron-transporting layer are arranged sequentially in this order from the light-emitting layer side to the cathode side. The first electron-transporting layer contains an indole derivative in which the ring nitrogen atom is substituted with an aromatic group and an aromatic ring is fused to the indole ring.

Abstract: Disclosed is an organic electroluminescent device (organic EL device) which has a simple structure and utilizes phosphorescence. The organic electroluminescent device is improved in luminescent efficiency and secured of sufficient driving stability. The organic electroluminescent device includes a luminescent layer or a plurality of organic compound thin film layers containing a luminescent layer formed between a pair of electrodes. The luminescent layer contains a compound composed of an Al complex of an oxyphenylbenzoxazole which is represented by the general formula (I) below as a host material, while containing an organic metal complex including Ru, Rh, Pd, Ag, Re, Os, Ir, Pt or Au as a guest material: where R1 to R8 independently represent hydrogen atom, alkyl group, aromatic group or the like; n represents 2 or 4; and Z represents aromatic group, triarylsilyl group or the like when n is 2, while representing Al(III) when n is 4.

Abstract: Disclosed is an organic electroluminescent device (organic EL device) which has a simple structure and utilizes phosphorescence. The organic electroluminescent device is improved in luminescent efficiency and secured of sufficient driving stability. The organic electroluminescent device includes a luminescent layer or a plurality of organic compound thin film layers containing a luminescent layer formed between a pair of electrodes. The luminescent layer contains a compound composed of an Al complex of an oxyphenylbenzoxazole which is represented by the general formula (I) below as a host material, while containing an organic metal complex including Ru, Rh, Pd, Ag, Re, Os, Ir, Pt or Au as a guest material: where R1to R8 independently represent hydrogen atom, alkyl group, aromatic group or the like; n represents 2 or 4; and Z represents aromatic group, triarylsilyl group or the like when n is 2, while representing Al(III) when n is 4.

Abstract: This invention provides an organic electroluminescent element (hereinafter referred to as an organic EL element) utilizing phosphorescence which shows improved luminous efficiency and assured driving stability and has a simple structure. The organic EL element comprises an anode, organic layers containing a hole-transporting layer, a lightemitting layer and an electron-transporting layer and a cathode piled one upon another on a substrate with the hole-transporting layer disposed between the light-emitting layer and the anode and the electron-transporting layer disposed between the light-emitting layer and the cathode. The light-emitting layer contains a pyridyl phenoxy zinc complex represented by the following general formula (I) as a host material and an organic metal complex containing at least one metal selected from Ru, Rh, Pd, Ag, Re, Os, Ir, Pt and Au as a guest material.