Abstract: The present invention provides a light-emitting element having less increase in driving voltage with the accumulation of light-emission time, and provides a light-emitting element having less increase in resistance value with the increase in film thickness. A light-emitting element includes a first layer, a second layer and a third layer between a first electrode and a second electrode. The first layer is provided to be closer to the first electrode than the second layer, and the third layer is provided to be closer to the second electrode than the second layer. The first layer is a layer including an aromatic amine compound and a substance showing an electron accepting property to the aromatic amine compound. The second layer includes a substance of which an electron transporting property is stronger than a hole transporting property, and a substance showing an electron donating property to the aforementioned substance.

Abstract: A light emitting element of the invention includes n pieces of light emitting layers (n is a natural number) between first and second electrodes. A first layer and a second layer are provided between the mth light emitting layer (m is a natural number of 1?m?n) and the m+1th light emitting layer. The first and second layers are contacted to each other. The first layer contain a substance that transports holes easily and a substance with an electron accepting property. The second layer contains a substance that transports electrons easily and a substance with an electron donating property. Molybdenum oxide is used as the substance with the electron accepting property.

Abstract: The present invention provides a light-emitting element having a structure in which the drive voltage is comparatively low and a light-emitting element in which the increase in the drive voltage over time is small. Further, the present invention provides a display device in which the drive voltage and the increase in the drive voltage over time are small and which can resist long-term use. A layer in contact with an electrode in a light-emitting element is a layer containing a P-type semiconductor or a hole-generating layer such as an organic compound layer containing a material having electron-accepting properties. The light-emitting layer is sandwiched between the hole-generating layers, and an electron-generating layer is sandwiched between the light-emitting layer and the hole-generating layer on a cathode side.

Abstract: It is an object of the present invention to provide a light-emitting element having a layer containing a light-emitting material and a transparent conductive film between a pair of electrodes, in which electric erosion of the transparent conductive film and metal can be prevented, and also to provide a light-emitting device using the light-emitting element. According to one feature of the invention, a light-emitting element includes a first layer 102 containing a light-emitting material, a second layer 103 containing a material having a donor level, a third layer 104 including a transparent conductive film, and a fourth layer 105 containing a hole-transporting medium between a first electrode 101 and a second electrode 106, in which the first layer 102, the second layer 103, the third layer 104, the fourth layer 105, and the second electrode 106 are provided sequentially, in which the second electrode 106 has a layer containing metal.

Abstract: To provide an electrode for an organic device which can be widely applied to organic devices by having both hole injection function and electron injection function. A carrier injection electrode layer 110 in which a metal for electron injection 112 (a metal having a work function of 4.2 eV or less) and a metal for hole injection 113 (a metal having a work function of more than 4.2 eV) are mixed with one kind of organic compound 111 is provided between a first organic layer 100a and a second organic layer 100b. Thus, carriers are injected into a carrier injection electrode layer 110 in the direction according to voltage application, and seemingly, current flows between an organic layer 100 and a metal electrode 101, or between the first organic layer 100a and the second organic layer 100b.

Abstract: It is an object of the present invention to provide a light-emitting element having, between a pair of electrodes, a layer containing a light-emitting material and a transparent conductive film, wherein the electric erosion of the transparent conductive film and reflective metal can be prevented and to provide a light-emitting device using the light-emitting element. According to the present invention, a first layer 102 containing a light-emitting material, a second layer 103 containing an N-type semiconductor, a third layer 104 including a transparent conductive film, and a fourth layer 105 containing a hole-transporting medium are provided between an anode 101 and a cathode 106, wherein the first layer 102, the second layer 103, the third layer 104, the fourth layer 105, and the cathode 106 are provided in order, and wherein the cathode has a layer containing reflective metal.

Abstract: An object of the present invention is to provide a light emitting element or a light emitting device that can be formed without any regard for a work function of an electrode. Another object of the invention is to provide a light emitting element or a light emitting device in that the range of choice for a material of an electrode can be widened. In an aspect of the invention, a light emitting device includes first, second and third layers between mutually-facing first and second electrodes. The first layer has a donor level. The second layer is a single layer or a laminated body containing a light emitting substance. The third layer has an acceptor level. When a potential of the second electrode is set higher than that of the first electrode, holes generated in the second layer are injected in the third layer.

Abstract: In the present invention, a light-emitting element operating at low driving voltage, consuming low power, emitting light with good color purity and manufactured in high yields can be obtained. A light-emitting element is disclosed with a configuration composed of a first layer containing a light-emitting material, a second layer, a third layer are formed sequentially over an anode to be interposed between the anode and a cathode in such a way that the third layer is formed to be in contact with the cathode. The second layer is made from n-type semiconductor, a mixture including that, or a mixture of an organic compound having a carrier transporting property and a material having a high electron donor property. The third layer is made from p-type semiconductor, a mixture including that, or a mixture of an organic compound having a carrier transporting property and a material having a high electron acceptor property.

Abstract: It is an object of the present invention to provide a light-emitting element having, between a pair of electrodes, a layer containing a light-emitting material and a transparent conductive film, wherein the electric erosion of the transparent conductive film and reflective metal can be prevented and to provide a light-emitting device using the light-emitting element. According to the present invention, a first layer 102 containing a light-emitting material, a second layer 103 containing an N-type semiconductor, a third layer 104 including a transparent conductive film, and a fourth layer 105 containing a hole-transporting medium are provided between an anode 101 and a cathode 106, wherein the first layer 102, the second layer 103, the third layer 104, the fourth layer 105, and the cathode 106 are provided in order, and wherein the cathode has a layer containing reflective metal.

Abstract: It is an object of the present invention to provide a material which is excellent in a hole injecting property and a hole transporting property, and to provide a light emitting element and a light emitting device using a material which is excellent in a hole injecting property and a hole transporting property. The present invention provides a carbazole derivative represented by a general formula (1). The carbazole derivative according to the present invention is excellent in the hole injecting property. By using the carbazole derivative according to the present invention as a hole injecting material for a hole injecting layer of a light emitting element, a driving voltage can be reduced. In addition, a lower driving voltage, improvement of the luminous efficiency, a longer life time, and higher reliability can be realized by applying the material to a light emitting element or a light emitting device.

Abstract: The present invention provides a light-emitting element having a structure in which the drive voltage is comparatively low and a light-emitting element in which the increase in the drive voltage over time is small. Further, the present invention provides a display device in which the drive voltage and the increase in the drive voltage over time are small and which can resist long-term use. A layer in contact with an electrode in a light-emitting element is a layer containing a P-type semiconductor or a hole-generating layer such as an organic compound layer containing a material having electron-accepting properties. The light-emitting layer is sandwiched between the hole-generating layers, and an electron-generating layer is sandwiched between the light-emitting layer and the hole-generating layer on a cathode side.

Abstract: It is an object of the present invention to provide a light-emitting element having a layer containing a light-emitting material and a transparent conductive film between a pair of electrodes, in which electric erosion of the transparent conductive film and metal can be prevented, and also to provide a light-emitting device using the light-emitting element. According to one feature of the invention, a light-emitting element includes a first layer 102 containing a light-emitting material, a second layer 103 containing a material having a donor level, a third layer 104 including a transparent conductive film, and a fourth layer 105 containing a hole-transporting medium between a first electrode 101 and a second electrode 106, in which the first layer 102, the second layer 103, the third layer 104, the fourth layer 105, and the second electrode 106 are provided sequentially, in which the second electrode 106 has a layer containing metal.

Abstract: Light-emitting elements have a problem that their light-extraction efficiency is low due to scattered light or reflected light inside the light-emitting elements. The light-extraction efficiency of the light-emitting elements needs to be enhanced by a new method. According to the present invention, a light-emitting element includes a first layer generating holes, a second layer including a light-emitting layer for each emission color and a third layer generating electrons between an anode and a cathode, and the thickness of the first layer is different depending on each layer including the light-emitting layer for each emission color. A layer in which an organic compound and a metal oxide are mixed is used as the first layer, and thus, the driving voltage is not increased even when the thickness is increased, which is preferable.

Abstract: A light emitting element of the invention includes n pieces of light emitting layers (n is a natural number) between first and second electrodes. A first layer and a second layer are provided between the mth light emitting layer (m is a natural number of 1?m?n) and the m+1th light emitting layer. The first and second layers are contacted to each other. The first layer contain a substance that transports holes easily and a substance with an electron accepting property. The second layer contains a substance that transports electrons easily and a substance with an electron donating property. Molybdenum oxide is used as the substance with the electron accepting property.

Abstract: An object of the present invention is to provide a light emitting element having slight increase in driving voltage with accumulation of light emitting time. Another object of the invention is to provide a light emitting element having slight increase in resistance value with increase in film thickness. A light emitting element of the invention includes a first layer for generating holes, a second layer for generating electrons and a third layer comprising a light emitting substance between first and second electrodes. The first and third layers are in contact with the first and second electrodes, respectively. The second and third layers are connected to each other so as to inject electrons generated in the second layer into the third layer when applying the voltage to the light emitting element such that a potential of the second electrode is higher than that of the first electrode.

Abstract: An object of the present invention is to provide a light emitting element having slight increase in driving voltage with accumulation of light emitting time. Another object of the invention is to provide a light emitting element having slight increase in resistance value with increase in film thickness. A light emitting element of the invention includes a first layer for generating holes, a second layer for generating electrons and a third layer comprising a light emitting substance between first and second electrodes. The first and third layers are in contact with the first and second electrodes, respectively. The second and third layers are connected to each other so as to inject electrons generated in the second layer into the third layer when applying the voltage to the light emitting element such that a potential of the second electrode is higher than that of the first electrode.

Abstract: It is an object of the present invention to provide a material which is excellent in a hole injecting property and a hole transporting property, and to provide a light emitting element and a light emitting device using a material which is excellent in a hole injecting property and a hole transporting property. The present invention provides a carbazol derivative represented by a general formula (1). The carbazol derivative according to the present invention is excellent in the hole injecting property. By using the carbazol derivative according to the present invention as a hole injecting material for a hole injecting layer of a light emitting element, a driving voltage can be reduced. In addition, a lower driving voltage, improvement of the luminous efficiency, a longer life time, and higher reliability can be realized by applying the material to a light emitting element or a light emitting device.

Abstract: An object of the prevent invention is to provide a light emitting element having slight increase in driving voltage with accumulation of light emitting time. Another object of the invention is to provide a light emitting element having slight increase in resistance value with increase in film thickness. A light emitting element of the invention includes a first layer for generating holes, a second layer for generating electrons and a third layer comprising a light emitting substance between first and second electrodes. The first and third layers are in contact with the first and second electrodes, respectively. The second and third layers are connected to each other so as to inject electrons generated in the second layer into the third layer when applying the voltage to the light emitting element such that a potential of the second electrode is higher than that of the first electrode.

Abstract: An object of the present invention is to provide a light emitting element which has low driving voltage and can increase lifetime longer than a conventional light emitting element. One feature is to include a plurality of layers which includes a layer containing a light emitting substance between first and second electrodes, in which at least one layer of the plurality of layers contains a carbazole derivative represented by General Formula (1) and a substance having an electron accepting property with respect to the carbazole derivative represented by General Formula (1). By employing this structure, the above object can be achieved.

Abstract: Light-emitting elements have a problem that their light-extraction efficiency is low due to scattered light or reflected light inside the light-emitting elements. The light-extraction efficiency of the light-emitting elements needs to be enhanced by a new method. According to the present invention, a light-emitting element includes a first layer generating holes, a second layer including a light-emitting layer for each emission color and a third layer generating electrons between an anode and a cathode, and the thickness of the first layer is different depending on each layer including the light-emitting layer for each emission color. A layer in which an organic compound and a metal oxide are mixed is used as the first layer, and thus, the driving voltage is not increased even when the thickness is increased, which is preferable.