JP2010049818A - Lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system including an optical communication means and having high emission luminance. <P>SOLUTION: The lighting system includes an organic electroluminescence element including at least an anode and a cathode provided on a support substrate, and at least one light emitting layer between the anode and the cathode. The organic electroluminescence element contains at least two kinds of light emitting materials, and has emission of the shortest wavelength of the light emitting materials as the optical communication means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lighting device.

  Conventionally, there is an electroluminescence display (ELD) as a light-emitting electronic display device. Examples of the constituent elements of ELD include inorganic electroluminescent elements and organic electroluminescent elements (hereinafter also referred to as organic EL elements). Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements.

  On the other hand, an organic EL element has a configuration in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and injects electrons and holes into the light emitting layer to recombine excitons. This is an element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when this exciton is deactivated, and can emit light at a voltage of several volts to several tens of volts. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type completely solid element, it has attracted attention from the viewpoints of space saving and portability.

  As the development of organic EL elements for practical use in the future, there is a demand for organic EL elements that emit light efficiently and with high luminance with lower power consumption. For example, in Japanese Patent No. 3093796, JP-A 63-264692 discloses a technique for doping a stilbene derivative, distyrylarylene derivative or tristyrylarylene derivative with a small amount of phosphor to improve emission luminance and extend the lifetime of the device. And 8-hydroxyquinoline aluminum complex as a host compound, and a device having an organic light emitting layer doped with a small amount of phosphor is disclosed. Japanese Unexamined Patent Publication No. 3-255190 discloses an 8-hydroxyquinoline aluminum complex. As a host compound, an element having an organic light emitting layer doped with a quinacridone dye is known.

  In the technique disclosed in the above-mentioned patent document, when the emission from the excited singlet is used, the generation ratio of the singlet exciton and the triplet exciton is 1: 3, so the generation probability of the luminescent excited species is 25%. Since the light extraction efficiency is about 20%, the limit of the external extraction quantum efficiency (ηext) is set to 5%.

  However, M.M. A. Baldo et al. , Nature, 395, 151-154 (1998), since Princeton University reported on an organic EL device using phosphorescence emission from an excited triplet. A. Baldo et al. , Nature, 403, 17, 750-753 (2000), and US Pat. No. 6,097,147, research on materials that exhibit phosphorescence at room temperature has become active.

  In addition, recently discovered organic EL devices that use phosphorescence can realize a luminous efficiency that is approximately four times that of previous devices that use fluorescence. Research and development of light-emitting element layer configurations and electrodes are performed all over the world. For example, S.M. Lamansky et al. , J .; Am. Chem. Soc. , 123, 4304 (2001), a number of compounds are being studied for synthesis centering on heavy metal complexes such as iridium complexes.

  The organic EL element is an all-solid element composed of an organic material film with a thickness of only about 0.1 μm between the electrodes, and the light emission can be achieved with a relatively low voltage of about 2V to 20V. It is a technology that is expected as a next-generation flat display and illumination.

  In addition, it is known to use an electroluminescence element for a lighting device and to perform visible light communication (see, for example, Patent Documents 1, 2, and 3).

  When using organic electroluminescence elements for lighting, there is a high demand for reducing power consumption, so the “phosphorescent emission” method with excellent luminous efficiency is preferable. However, phosphorescence emission has a large afterglow due to a fundamental problem. Even with an Ir complex compound having the least afterglow, the phosphorescence lifetime is several microseconds, and it takes about 1000 times as long as fluorescence emission.

  As can be easily imagined from this fact, it is difficult to apply a phosphorescent organic electroluminescence element to visible light communication in a high frequency band of 1 MHz or higher.

On the other hand, since the fluorescence emission has a lifetime of about several p seconds, visible light communication in the MHz band is possible, but it is not suitable in terms of power consumption.
JP 2006-270422 A JP 2007-165728 A JP 2007-97071 A

  The objective of this invention is providing the illuminating device which has an optical communication means and has high light emission luminance.

  The above object of the present invention has been achieved by the following constitution.

  1. An organic electroluminescence element having at least an anode and a cathode on a support substrate and having at least one light emitting layer between the anode and the cathode, and the organic electroluminescence element contains at least two kinds of light emitting materials And an illuminating device having light emission of the shortest wavelength of the luminescent material as an optical communication means.

  2. 2. The illumination device according to 1 above, wherein the light having the shortest wavelength is fluorescent light emission.

  3. 3. The illumination device according to 1 or 2 above, wherein a difference in emission maximum wavelength between the shortest wavelength light emission and the next shortest wavelength light emission is 20 nm to 250 nm.

  4). 4. The lighting device according to any one of 1 to 3, wherein at least one of the light emission of the light emitting material is a phosphorescent compound.

  5. The lighting device according to any one of the above items 1 to 4, wherein the next shortest wavelength emission is phosphorescence emission, and the emission maximum wavelength of the phosphorescence emission is in a range of 460 nm to 480 nm. .

  6). 6. The lighting device according to any one of 1 to 5, wherein at least one of the phosphorescent compounds is an orthometalated complex having a partial structure represented by the following general formula (1). .

[Wherein R ₁ represents a substituent. Z represents a nonmetallic atom group necessary for forming a 5- to 7-membered ring. n1 represents the integer of 0-5. B _{1 to} B ₅ each represent a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom, and at least one represents a nitrogen atom. M ₁ represents a transition metal element of Group 8 to Group 10 in the periodic table. X ₁ and X ₂ each represent a carbon atom, a nitrogen atom, or an oxygen atom, and L ₁ represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. ]
7). Any one of the above 1 to 6, wherein a layer containing at least one light emitting material emitting light of the shortest wavelength and a layer containing at least one light emitting material are provided separately. The lighting device according to item 1.

  8). 8. The lighting device according to any one of the above items 1 to 7, further comprising a light receiving unit as a configuration, wherein a detection wavelength of the light receiving unit is set to less than 450 nm.

  9. Any one of the above 1 to 8, characterized in that it has a transmitting means, and the transmitting means transmits both a low frequency band of less than 1 MHz and a high frequency band of 1 MHz or more from the same light emitting element. The lighting device according to item 1.

  10. 10. The low frequency band signal reception is detected in a wavelength region of 450 nm or more, and the high frequency band signal reception is detected in a wavelength region of less than 450 nm. Lighting equipment.

  11. A white illumination device comprising the illumination device according to any one of 1 to 10 above.

  According to the present invention, it is possible to provide an illuminating device having an optical communication means and having high light emission luminance.

  In the illuminating device of this invention, by having the structure of any one of Claims 1-10, the illuminating device which has an optical communication means and has high light emission brightness was able to be provided. . Moreover, the illuminating device which has the said illuminating device was able to be obtained collectively.

  Hereinafter, details of each component according to the present invention will be sequentially described.

《Lighting device》
The lighting device of the present invention will be described.

  As a result of various studies on the above-mentioned problems, the present inventors use fluorescent light emission only in a short wave region that is substantially unaffected by phosphorescent light emission, and perform other light emission by phosphorescent light emission. It was possible to provide an illuminating device having an optical communication means that satisfies both frequency bands and having high emission luminance.

  In addition, by adopting such a configuration (only short-wave components are fluorescent, and other light-emitting components are phosphorescent), simple communication functions such as position information are performed by detecting phosphorescent light emission, and images and High-density communication such as audio information can be performed simultaneously by detecting fluorescence emission, and it has become possible to add functions that were difficult with conventional visible light communication.

  The illuminating device of the present invention can use a light emitting unit as an optical communication means in a configuration of an optical communication system (however, the optical communication system is not shown).

  The optical communication system used in the present invention includes, for example, at least one optical transmission device and at least one optical reception device as a system configuration, and the optical transmission device transmits a communication signal to the optical reception device. Thus, at least one-way optical communication can be performed.

  Further, each of the optical transmission device and the optical reception device described above includes, for example, a bidirectional light transmission when the optical transmission device also has an optical reception function and the optical reception device further has an optical transmission function. It is also possible to perform communication. Specifically, bidirectional light communication is possible by the organic EL element having an optical transmission function and the organic photodiode having an optical reception function.

  In the optical communication system as described above, the illumination device of the present invention is a light emitting unit of an optical transmission device in the case of one-way optical communication, and an optical transmission device and / or in the case of bidirectional optical communication. It can be used for a light emitting unit of an optical receiver.

  In the illuminating device of the present invention, which is used in a light emitting unit of an optical transmission device or an optical reception device of an optical communication system, an organic EL element is used as a light emitting element.

  The organic EL element according to the lighting device of the present invention has at least two kinds of light emitting materials, and the light emission of the shortest wavelength of the light emitting material is used as an optical communication means. From the viewpoint of performing reliable optical communication (visible light communication), it is preferable to use fluorescent light emission.

  In addition, from the viewpoint of obtaining high-intensity illumination of the illumination device of the present invention, the light other than the light having the shortest wavelength (including ultraviolet light and visible light) is preferably used for illumination. At least one of the light-emitting materials contained in the organic EL element is preferably a phosphorescent compound. The phosphorescent compound will be described in detail in the configuration of the organic EL element.

  Moreover, the illuminating device of this invention can be used as a display device, a display, and various light emission light sources. As light emitting sources, for example, home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources of optical storage media, light sources of electrophotographic copying machines, light sources of optical communication processors, light sources of optical sensors, etc. Although it is not limited to this, it can be effectively used particularly as a backlight of a liquid crystal display device and an illumination light source.

  The color emitted by the illumination device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color when the result measured with CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

Further, when the lighting device of the present invention is a white lighting device, white means that the chromaticity in the CIE 1931 color system at 1000 cd / m ² is measured when the 2-degree viewing angle front luminance is measured by the above method. It means that it is in the region of X = 0.33 ± 0.07 and Y = 0.33 ± 0.1.

<< Constituent Layer of Organic EL Element Used in Lighting Device of Present Invention >>
The constituent layers of the organic EL element included in the lighting device of the present invention will be described. Here, a white illumination device (also referred to as a white light emitting device) is preferably used as the illumination device of the present invention.

  Below, although the specific example of the white illuminating device (white light-emitting device) used preferably among the illuminating devices of this invention is shown in FIGS. 1-22, this invention is not limited to these.

  FIG. 1 is a schematic diagram showing an example of an organic EL element used in the illumination device (illumination device having a white light-emitting organic EL element) of the present invention, in which the light-emitting layer has a four-layer structure.

  In FIG. 1, the first phosphorescent layer has a red phosphorescent dopant, the luminescent host compound 1, the second phosphorescent layer has a green phosphorescent dopant, the luminescent host compound 2, and the third phosphorescent layer has blue phosphorescence. The luminescent dopant, the luminescent host compound 3, and the fourth luminescent layer contain a blue fluorescent luminescent dopant and a luminescent host compound 4, respectively.

  The hole injection layer contains a hole injection material, the hole transport layer contains a hole transport material, the electron transport layer contains an electron transport material, and the electron injection layer contains an electron injection material. Yes.

  The light emitting host compounds 1 to 4 may be the same as or different from each other, and the hole injection layer and the hole transport layer may be formed as a single layer, and may be used as a hole injection / hole transport layer. The injection layer and the electron transport layer may be formed as a single layer to form an electron injection / electron transport layer.

  Moreover, the material contained in the structural layer of the white illuminating device (white light emitting organic EL element) shown in each of FIGS. 1 to 22 will be described in detail later.

  FIG. 2 is a schematic view showing an example of an organic EL element used in the white lighting device of the present invention, in which the light emitting layer has a four-layer structure. The first light emitting layer has a red phosphorescent light emitting dopant, a light emitting host compound 1. The second light emitting layer contains a green phosphorescent light emitting dopant and the light emitting host compound 2, the third light emitting layer contains a blue fluorescent light emitting dopant and the light emitting host compound 3, and the fourth light emitting layer contains These show the structural example in which the blue phosphorescence emission dopant and the light emission host compound 4 contain.

  FIG. 3 is a schematic diagram showing one example of each of the organic EL elements used in the white illumination device of the present invention, in which the light emitting layer has a four-layer structure. The first light emitting layer includes a green phosphorescent dopant, light emission The host compound 1 is contained, the second light emitting layer contains the red phosphorescent light emitting dopant and the light emitting host compound 2, the third light emitting layer contains the blue fluorescent light emitting dopant and the light emitting host compound 3, and the fourth The light emitting layer shows a configuration example in which a blue phosphorescent light emitting dopant and the light emitting host compound 4 are contained.

  2 and 3 are the same as those in FIG.

  Next, the example of the organic EL element used for the white illuminating device of this invention whose light emitting layer is 3 layer structure is shown. In the description of the layer structure, the following structure will be described, particularly focusing on the blue fluorescent light-emitting dopant containing layer that emits light with the shortest wavelength.

  FIG. 4 is a schematic view showing an example of an organic EL element used in the illumination device (illumination device having a white light-emitting organic EL element) of the present invention, in which the light emitting layer has a three-layer structure.

  In FIG. 4, the first phosphorescent layer has a red phosphorescent light emitting dopant, the light emitting host compound 1, the second light emitting layer has a green phosphorescent light emitting dopant, the light emitting host compound 2, and the third light emitting layer has a blue fluorescent light emission. A dopant, a blue phosphorescent light emitting dopant, and a light emitting host compound 3 are contained.

  The luminescent host compounds 1 to 3 may be the same or different, and the other constituent layers are the same as those in FIG.

  FIG. 5 is a schematic diagram showing an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure. The first light emitting layer contains a red phosphorescent light emitting dopant and a light emitting host compound 1. In the second light emitting layer, a configuration example in which a green phosphorescent light emitting dopant, a blue fluorescent light emitting dopant and a light emitting host compound 2 are contained is shown.

  FIG. 6 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure. The first light emitting layer includes a red phosphorescent light emitting dopant, a blue fluorescent light emitting dopant, and light emission. Configuration example in which the host compound 1 is contained, the second light emitting layer contains the green phosphorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains the blue phosphorescent light emitting dopant and the light emitting host compound 3. Indicates.

  FIG. 7 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a three-layer structure. A red phosphorescent dopant, a green phosphorescent dopant, A configuration example in which the light emitting host compound 1 is contained, the second light emitting layer contains the blue fluorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains the blue phosphorescent light emitting dopant and the light emitting host compound 3. Show.

  FIG. 8 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a three-layer structure. A red phosphorescent dopant, a green phosphorescent dopant, A configuration example in which the light emitting host compound 1 is contained, the second light emitting layer contains the blue phosphorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains the blue fluorescent light emitting dopant and the light emitting host compound 3 is shown.

  FIG. 9 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a three-layer structure. A blue phosphorescent dopant, a green phosphorescent dopant, A configuration example in which the phosphorescent host compound 1 and the second phosphorescent layer contain the red phosphorescent dopant, the phosphorescent host compound 2 and the third phosphorescent layer contain the blue fluorescent dopant and the phosphorescent host compound 3 is shown.

  FIG. 10 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure. A blue phosphorescent light emitting dopant, a green phosphorescent light emitting dopant, A configuration example in which the light emitting host compound 1 is contained, the second light emitting layer contains a blue fluorescent light emitting dopant, the light emitting host compound 2, and the third light emitting layer contains a red phosphorescent light emitting dopant and the light emitting host compound 3 is shown.

  FIG. 11 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a three-layer structure. The first light-emitting layer includes a blue phosphorescent light-emitting dopant, a blue fluorescent light-emitting dopant, and light emission. A configuration example in which the host compound 1 is contained, the second light emitting layer contains the green phosphorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains the red phosphorescent light emitting dopant and the light emitting host compound 3 is shown.

  FIG. 12 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure. The first light emitting layer includes a blue phosphorescent light emitting dopant, a blue fluorescent light emitting dopant, and light emission. Configuration example in which the host compound 1 is contained, the second light emitting layer contains the red phosphorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains the green phosphorescent light emitting dopant and the light emitting host compound 3. Indicates.

  FIG. 13 is a schematic diagram showing an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure, and the first light emitting layer contains a red phosphorescent light emitting dopant and the light emitting host compound 1. The second light emitting layer contains the blue phosphorescent light emitting dopant, the blue fluorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains the green phosphorescent light emitting dopant and the light emitting host compound 3. Indicates.

  FIG. 14 is a schematic diagram showing an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure, and the first light emitting layer contains the green phosphorescent light emitting dopant and the light emitting host compound 1. The second light emitting layer contains a blue phosphorescent light emitting dopant, a blue fluorescent light emitting dopant, and a light emitting host compound 2, and the third light emitting layer contains a red phosphorescent light emitting dopant and a light emitting host compound 3. Indicates.

  FIG. 15 is a schematic view showing an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a three-layer structure. The first light emitting layer contains a green phosphorescent light emitting dopant and a light emitting host compound 1. The second light emitting layer contains a red phosphorescent light emitting dopant and the light emitting host compound 2, and the third light emitting layer contains a blue phosphorescent light emitting dopant, a blue fluorescent light emitting dopant, and a light emitting host compound 3. Indicates.

  4 to 15, the luminescent host compounds 1 to 3 may be the same or different. Other constituent layers are the same as those in FIG.

  FIG. 16 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a two-layer structure. The first light-emitting layer includes a green phosphorescent dopant, a blue phosphorescent dopant, A configuration example in which a blue fluorescent light emitting dopant and a light emitting host compound 1 are contained, and a red phosphorescent light emitting dopant and a light emitting host compound 2 are contained in the second light emitting layer is shown.

  FIG. 17 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a two-layer structure. The first light emitting layer includes a green phosphorescent dopant, a red phosphorescent dopant, A configuration example in which the light emitting host compound 1 is contained, and the second light emitting layer contains the blue phosphorescent light emitting dopant, the blue fluorescent light emitting dopant, and the light emitting host compound 2 is shown.

  FIG. 18 is a schematic diagram showing an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a two-layer structure. The first light emitting layer has a blue fluorescent light emitting dopant, a green phosphorescent light emitting dopant, and a red color. The structural example in which the phosphorescence emission dopant and the light emission host compound 1 are contained, and the blue light emission emission dopant and the light emission host compound 2 are contained in the 2nd light emission layer is shown.

  FIG. 19 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a two-layer structure. The first light emitting layer includes a blue fluorescent light emitting dopant, a red phosphorescent light emitting dopant, and light emission. A configuration example in which the host compound 1 is contained and the second phosphor layer contains the blue phosphorescent dopant, the green phosphorescent dopant, and the phosphorescent host compound 2 is shown.

  FIG. 20 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a two-layer structure. The first light-emitting layer includes a blue fluorescent light-emitting dopant, a green phosphorescent light-emitting dopant, and light emission. The structural example in which the host compound 1 is contained and the second phosphorescent layer contains the blue phosphorescent dopant, the red phosphorescent dopant, and the phosphorescent host compound 2 is shown.

  FIG. 21 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light-emitting layer has a two-layer structure. The first light-emitting layer includes a blue phosphorescent light-emitting dopant, a green phosphorescent light-emitting dopant, A configuration example in which a red phosphorescent light emitting dopant and a light emitting host compound 1 are contained, and a blue phosphorescent light emitting dopant, a blue fluorescent light emitting dopant, and a light emitting host compound 2 are contained in the second light emitting layer is shown.

  16 to 21, the luminescent host compounds 1 and 2 may be the same or different. Other constituent layers are the same as those in FIG.

  FIG. 22 is a schematic diagram illustrating an example of an organic EL element used in the lighting device of the present invention, in which the light emitting layer has a single layer structure. The first light emitting layer includes a blue phosphorescent light emitting dopant, a green phosphorescent light emitting dopant, The structural example in which the red phosphorescence emission dopant, the blue fluorescence emission dopant, and the light emission host compound 1 are contained is shown. Other constituent layers are the same as those in FIG.

  One example of the lighting device of the present invention having the organic EL elements as shown in FIGS. 1 to 22 is shown in FIGS. 23 and 24, but the lighting device of the present invention is not limited thereto.

  FIG. 23 shows a schematic diagram of the lighting device of the present invention, in which the organic EL element 101 is covered with a stainless steel sealing can 102. As an example of the organic EL element 101, the organic EL elements shown in FIGS. 1 to 22 are used.

  The sealing work with a stainless steel sealing can is performed in a glove box under a nitrogen atmosphere (in an atmosphere of high purity nitrogen gas with a purity of 99.999% or more) without bringing the organic EL element 101 into contact with the atmosphere. Bonding was performed using a stainless steel sealing can 102 and an ultraviolet curable adhesive.

  FIG. 24 shows a cross-sectional view of the lighting device of the present invention. In FIG. 23, 105 denotes a cathode, 106 denotes a constituent layer of an organic EL element, and 107 denotes a glass substrate with a transparent electrode.

  The stainless steel sealing can 102 is filled with nitrogen gas 108 and provided with a water catching agent 109 (using barium oxide as a dehydrating agent).

  In addition, in the illuminating device and white illuminating device of this invention, the following aspects are also preferably used.

(A) A charge adjustment layer for adjusting the charge may be appropriately provided between the light emitting layer and the light emitting layer. (B) The anode (also referred to as an anode side substrate or the like) is opaque and the cathode (cathode side substrate or the like). May also form a top emission structure formed of a very thin metal or a laminate of a very thin metal and a transparent electrode,
(C) A double-sided light-emitting structure formed of a cathode (also referred to as a cathode-side substrate or the like) and an electrode that is transparent (formed with a very thin metal or a laminate of a very thin metal and a transparent electrode) may be formed.
(D) A multi-photon emission element in which [electron transport layer / electron injection layer / dielectric layer] is inserted between the light emitting layer and the light emitting layer may be formed.
And the like.

  In the organic EL element used in the lighting device of the present invention, the blue light emitting layer preferably has a light emission maximum wavelength of 430 nm to 480 nm, the green light emitting layer has a light emission maximum wavelength of 510 nm to 550 nm, and the red light emitting layer emits light. A monochromatic light emitting layer having a maximum wavelength in the range of 600 nm to 640 nm is preferable, and a display device using these is preferable.

  Alternatively, a white light emitting layer may be formed by laminating at least three light emitting layers. Further, a non-light emitting intermediate layer may be provided between the light emitting layers.

  The organic EL element included in the lighting device of the present invention is preferably a white light emitting layer, and is preferably a white lighting device using these.

  Examples of the emission spectrum of a white organic EL element preferably used in the lighting device of the present invention are shown in FIGS. 25 and 26 below, but the present invention is not limited to these.

  FIG. 25 shows an example of an emission spectrum of a white light-emitting organic EL device containing a blue fluorescent light-emitting dopant of FIG. 30, a blue phosphorescent light-emitting dopant of FIG. 27, and a red phosphorescent light-emitting dopant of FIG. Show.

  FIG. 26 shows a white light-emitting organic EL element containing a blue phosphorescent light-emitting dopant, a green phosphorescent light-emitting dopant, a red phosphorescent light-emitting dopant, and a blue fluorescent light-emitting dopant described in FIGS. This shows an example of the emission spectrum.

  The illuminating device of the present invention has, for example, a white light emitting organic EL element as shown in FIGS. 25 and 26, but is used as light communication means (transmitting and / or receiving). ) Is the light having the shortest wavelength (light emission) of the light-emitting material contained in the white light-emitting organic EL element of 420 nm to 440 nm.

  In the emission spectrum of the white light emitting organic EL element of FIGS. 25 and 26, as the light having the shortest wavelength, fluorescent light emitted from the blue fluorescent light emitting dopant shown in FIG. 30 is used as the optical communication means.

  By using such fluorescent light emission for optical communication, it is possible to perform optical communication with high-speed response and use a light-emitting material exhibiting a phosphorescence emission spectrum as shown in FIGS. Thus, a high-luminance white lighting device can be obtained.

  Then, although an example of the emission spectrum of the luminescent material used for the organic EL element which the white light emission illumination device of this invention has is shown in FIGS. 27-30, respectively, this invention is not limited to these.

  FIG. 27 is an example of an emission spectrum of a blue phosphorescent dopant according to the luminescent material of the lighting device of the present invention, FIG. 28 is an example of an emission spectrum of a green phosphorescent dopant, and FIG. FIG. 30 shows an example of the emission spectrum of the photoluminescent dopant, and FIG. 30 shows an example of the emission spectrum of the blue fluorescent dopant.

  27 to 30, the blue phosphorescent light emitting material (also referred to as blue phosphorescent light emitting dopant), the green phosphorescent light emitting material (also referred to as green phosphorescent light emitting dopant), and the red phosphorescent light emitting material (red phosphorescent light emitting). The dopant) and the blue fluorescent light emitting material (blue fluorescent light emitting dopant) will be described in detail in the light emitting layer described later.

  Hereinafter, each layer which comprises the organic EL element which the illuminating device of this invention has is demonstrated.

<Light emitting layer>
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. May be the interface between the light emitting layer and the adjacent layer.

  The total film thickness of the light emitting layer is not particularly limited, but from the viewpoint of improving the uniformity of the film, preventing unnecessary application of high voltage during light emission, and improving the stability of the emission color with respect to the drive current. It is preferable to adjust in the range of 2 nm to 5 μm, more preferably in the range of 2 nm to 200 nm, and particularly preferably in the range of 10 nm to 20 nm.

  For the production of the light-emitting layer, a light-emitting dopant or a host compound, which will be described later, is formed and formed by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an ink-jet method. it can.

  The organic EL element according to the lighting device of the present invention contains at least two kinds of light emitting materials as light emitting materials, and the light emitting layer includes a light emitting host compound and at least one kind of light emitting dopant (phosphorescent dopant (phosphorescent light emitting). Or a fluorescent dopant). The light emitting layer may contain a plurality of light emitting materials.

(Luminescent dopant)
The light emitting dopant according to the present invention will be described.

  As the light-emitting dopant according to the present invention, a fluorescent dopant (also referred to as a fluorescent compound) or a phosphorescent dopant (also referred to as a phosphorescent emitter, a phosphorescent compound, a phosphorescent compound, or the like) can be used. From the viewpoint of obtaining an organic EL device with high luminous efficiency, the light emitting dopant used in the light emitting layer or the light emitting unit of the organic EL device of the present invention (sometimes simply referred to as a light emitting material) contains the above host compound. At the same time, it is preferable to contain a phosphorescent dopant.

  The illuminating device of the present invention uses the light having the shortest wavelength among the luminescent materials according to the present invention as an optical communication means. From the viewpoint of suitability for high-speed communication (fast response suitability), a fluorescent dopant (fluorescent compound) It is preferable to use fluorescent light emitted from a fluorescent compound.

  Moreover, it is preferable that the difference of the light emission maximum wavelength of light emission with the shortest wavelength and light emission with the next short wavelength is in the range of 20 nm to 250 nm.

(Fluorescent dopant (also called fluorescent compound, fluorescent compound, etc.))
Fluorescent dopants (fluorescent compounds) that emit fluorescent light according to the present invention include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes. Examples thereof include dyes, pyrylium dyes, perylene dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

  Incidentally, a blue fluorescent light-emitting material (blue fluorescent light-emitting dopant) having a short-wavelength emission spectrum as shown in FIG. 30 can be appropriately selected from the above-mentioned fluorescent dopants.

(Phosphorescent dopant)
The phosphorescent dopant according to the present invention will be described.

  The phosphorescent dopant according to the present invention is a compound in which light emission from an excited triplet is observed. Specifically, the phosphorescent dopant is a compound that emits phosphorescence at room temperature (25 ° C.) and has a phosphorescence quantum yield of 25. Although it is defined as a compound of 0.01 or more at ° C., a preferable phosphorescence quantum yield is 0.1 or more.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence dopant according to the present invention achieves the phosphorescence quantum yield (0.01 or more) in any solvent. That's fine.

  There are two types of light emission of phosphorescent dopants in principle. One is the recombination of carriers on the host compound to which carriers are transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent dopant. The energy transfer type that obtains light emission from the phosphorescent dopant, and the other is that the phosphorescent dopant becomes a carrier trap, carrier recombination occurs on the phosphorescent dopant, and light emission from the phosphorescent dopant is obtained. Although it is a trap type, in any case, the excited state energy of the phosphorescent dopant is required to be lower than the excited state energy of the host compound.

  The phosphorescent dopant can be appropriately selected from known materials used for the light emitting layer of the organic EL element, but from the viewpoint of obtaining a high-luminance lighting device, at least one of the light emission of the light emitting material is A phosphorescent compound is preferred.

  The next short wavelength emission is phosphorescence emission, and the emission maximum wavelength of the phosphorescence emission is preferably in the range of 460 nm to 480 nm.

  Furthermore, the phosphorescent compound according to the present invention is preferably an orthometalated complex having the partial structure described in the general formula (1).

<< Orthometalated Complex Having Partial Structure Represented by General Formula (1) >>
The orthometalated complex having a partial structure represented by the general formula (1) according to the present invention will be described.

  In the orthometalated complex having the partial structure represented by the general formula (1) according to the present invention, light emission from the excited triplet is observed, but the phosphorescence quantum yield is 0.001 or more at 25 ° C. More preferably, the phosphorescence quantum yield is 0.01 or more, and particularly preferably 0.1 or more.

  The phosphorescent quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence quantum yield should just be achieved in any solvent.

  The orthometalated complex having a partial structure represented by the general formula (1) preferably has a HOMO of −5.15 to −3.50 eV and a LUMO of −1.25 to +1.00 eV, more preferably , HOMO is −4.80 to −3.50 eV, and LUMO is −0.80 to +1.00 eV.

In the general formula (1), examples of the substituent represented by R ₁ include an alkyl group (eg, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group). , Dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (eg, vinyl group, allyl group, etc.), alkynyl group (eg, ethynyl group, Propargyl group etc.), aromatic hydrocarbon ring group (aromatic carbocyclic group, aryl group, etc.), for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl Group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenyl Phenylyl group, etc.), aromatic heterocyclic groups (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazole- 1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, Dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom) ), Quinoxalinyl group, pyridazinyl group, triazi Group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, Hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, Methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (for example, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, Phthalylthio group), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, Naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group) , Phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl) Group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group) , Ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonyl) Amino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecyl Carbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, Octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc., ureido group (for example, methylureido group, ethylureido group, pentylureido) Group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc. , Sulfinyl group (eg, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl Group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group) 2-pyridylsulfonyl group), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentyla) Mino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc., cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group) Group, triphenylsilyl group, phenyldiethylsilyl group, etc.). Of these substituents, preferred are an alkyl group and an aryl group.

  In the general formula (1), examples of the 5- to 7-membered ring formed by Z include a benzene ring, naphthalene ring, pyridine ring, pyrimidine ring, pyrrole ring, thiophene ring, pyrazole ring, imidazole ring, oxazole ring and thiazole. A ring etc. are mentioned. Of these, a benzene ring is preferred.

  Moreover, the 5- to 7-membered ring formed by Z may further have a condensed ring.

In the general formula (1), the nitrogen-containing heterocycle formed by B _{1 to} B ₅ is preferably a monocycle. Examples include pyrrole ring, pyrazole ring, imidazole ring, triazole ring, tetrazole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, oxadiazole ring, and thiadiazole ring. Among these, a pyrazole ring and an imidazole ring are preferable, and an imidazole ring is more preferable.

  These rings may be further substituted with the above substituents. Preferred as the substituent are an alkyl group and an aryl group, and more preferably an aryl group.

In the general formula (1), specific examples of the bidentate ligand represented by X ₁ -L ₁ -X ₂ include, for example, substituted or unsubstituted phenylpyridine, phenylpyrazole, phenylimidazole, phenyltriazole, Examples include phenyltetrazole, pyrazabole, picolinic acid, and acetylacetone. These groups may be further substituted with the above substituents.

  In the general formula (1), m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. Especially, the case where m2 is 0 is preferable.

In the general formula (1), M ₁ represents a group 8-10 transition metal element (also simply referred to as a transition metal) in the periodic table of the elements, among which iridium and platinum are preferable, and iridium is more preferable.

  The phosphorescent compound represented by the general formula (1) may or may not have a polymerizable group or a reactive group.

  Hereinafter, although the specific example of the ortho metalation complex (compound) represented by General formula (1) is shown, this invention is not limited to these.

  The synthesis of the phosphorescent compound represented by the general formula (1) according to the present invention is described in, for example, Organic Letter vol. 16, 2579-2581 (2001), Inorganic Chemistry Vol. 30, No. 8, 1685-1687 (1991), J. MoI. Am. Chem. Soc. 123, 4304 (2001), Inorganic Chemistry, Vol. 40, No. 7, 1704-1711 (2001), Inorganic Chemistry, Vol. 41, No. 12, 3055-3066 (2002), New Journal of Chemistry, Vol. 26 1171 (2002), European Journal of Organic Chemistry Vol. 4, pages 695-709 (2004), and further by applying methods such as references described in these documents.

  The phosphorescent dopant according to the present invention is preferably a complex compound containing a group 8-10 metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, or a platinum compound (platinum complex system). Compound) and rare earth complexes, and most preferred is an iridium compound.

  Furthermore, the phosphorescent compound represented by the general formula (1) and a conventionally known phosphorescent dopant can be used in combination.

  Although the specific example of the compound used as a phosphorescence dopant which can be used together is shown below, this invention is not limited to these.

(Host compound (also called luminescent host))
The host compound used in the present invention will be described.

  Here, in the present invention, the host compound means a phosphorescent quantum yield of phosphorescence emission at a room temperature (25 ° C.) having a mass ratio of 20% or more in the compound contained in the light emitting layer. Is defined as a compound of less than 0.1. The phosphorescence quantum yield is preferably less than 0.01. Moreover, it is preferable that the mass ratio in the layer is 20% or more among the compounds contained in a light emitting layer.

  As the host compound, known host compounds may be used alone or in combination of two or more. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. Moreover, it becomes possible to mix different light emission by using multiple types of light emission dopants mentioned later, and, thereby, arbitrary luminescent colors can be obtained.

  The light emitting host used in the present invention may be a conventionally known low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (deposition polymerization property). A light emitting host), or one or more compounds such as the material C may be used.

  As a known host compound that may be used in combination, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable.

  Specific examples of known host compounds include compounds described in the following documents.

  JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445 gazette, 2002-343568 gazette, 2002-141173 gazette, 2002-352957 gazette, 2002-203683 gazette, 2002-363227 gazette, 2002-231453 gazette, No. 003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.

  Next, an injection layer, a blocking layer, an electron transport layer, and the like used as a constituent layer of the organic EL element of the present invention will be described.

<< Injection layer: electron injection layer, hole injection layer >>
The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, it exists between the anode and the light emitting layer or the hole transport layer and between the cathode and the light emitting layer or the electron transport layer. May be.

  An injection layer is a layer provided between an electrode and an organic layer in order to reduce drive voltage and improve light emission luminance. “Organic EL element and its forefront of industrialization (issued by NTT Corporation on November 30, 1998) 2), Chapter 2, “Electrode Materials” (pages 123 to 166) in detail, and includes a hole injection layer (anode buffer layer) and an electron injection layer (cathode buffer layer).

  The details of the anode buffer layer (hole injection layer) are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, copper phthalocyanine is used. Examples thereof include a phthalocyanine buffer layer represented by an oxide, an oxide buffer layer represented by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

  The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 nm to 5 μm although it depends on the material.

<Blocking layer: hole blocking layer, electron blocking layer>
The blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film as described above. For example, it is described in JP-A Nos. 11-204258, 11-204359, and “Organic EL elements and their forefront of industrialization” (issued by NTT, Inc. on November 30, 1998). There is a hole blocking (hole blocking) layer.

  The hole blocking layer has a function of an electron transport layer in a broad sense, and is made of a hole blocking material that has a function of transporting electrons and has a remarkably small ability to transport holes. The probability of recombination of electrons and holes can be improved by blocking. Moreover, the structure of the electron carrying layer mentioned later can be used as a hole-blocking layer concerning this invention as needed.

  The hole blocking layer of the organic EL device of the present invention is preferably provided adjacent to the light emitting layer.

  The hole blocking layer preferably contains the azacarbazole derivative mentioned as the host compound.

  In the present invention, when a plurality of light emitting layers having different light emission colors are provided, the light emitting layer having the shortest wavelength of light emission is preferably closest to the anode among all the light emitting layers. In this case, it is preferable to additionally provide a hole blocking layer between the shortest wave layer and the light emitting layer next to the anode next to the anode. Furthermore, it is preferable that 50% by mass or more of the compound contained in the hole blocking layer provided at the position has an ionization potential of 0.3 eV or more larger than the host compound of the shortest wave emitting layer.

  The ionization potential is defined by the energy required to emit an electron at the HOMO (highest occupied molecular orbital) level of the compound to the vacuum level, and can be obtained by the following method, for example.

  (1) Using Gaussian 98 (Gaussian 98, Revision A.11.4, MJ Frisch, et al, Gaussian, Inc., Pittsburgh PA, 2002.), a molecular orbital calculation software manufactured by Gaussian, USA The ionization potential can be obtained as a value obtained by rounding off the second decimal place of the value (eV unit converted value) calculated by performing structural optimization using B3LYP / 6-31G *. This calculation value is effective because the correlation between the calculation value obtained by this method and the experimental value is high.

  (2) The ionization potential can also be obtained by a method of directly measuring by photoelectron spectroscopy. For example, a method known as ultraviolet photoelectron spectroscopy can be suitably used by using a low energy electron spectrometer “Model AC-1” manufactured by Riken Keiki Co., Ltd.

  On the other hand, the electron blocking layer has a function of a hole transport layer in a broad sense, and is made of a material that has a function of transporting holes and has an extremely small ability to transport electrons, and transports electrons while transporting holes. By blocking, the recombination probability of electrons and holes can be improved. Moreover, the structure of the positive hole transport layer mentioned later can be used as an electron blocking layer as needed. The film thickness of the hole blocking layer and the electron transport layer according to the present invention is preferably 3 nm to 100 nm, and more preferably 5 nm to 30 nm.

《Hole transport layer》
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

  The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two of those described in US Pat. No. 5,061,569. Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material as described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. In the present invention, these materials are preferably used because a light-emitting element with higher efficiency can be obtained.

  The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. it can.

  Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

  Alternatively, a hole transport layer having a high p property doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use a hole transport layer having such a high p property because a device with lower power consumption can be produced.

《Electron transport layer》
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from among conventionally known compounds. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like.

  Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  Also, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum, Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and the central metals of these metal complexes are In, Mg, Cu , Ca, Sn, Ga, or Pb can also be used as an electron transport material.

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material.

  In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc. as in the case of the hole injection layer and the hole transport layer Can also be used as an electron transporting material.

  The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method.

  Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  Further, an electron transport layer having a high n property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use an electron transport layer having such a high n property because an element with lower power consumption can be manufactured.

"anode"
As the anode in the organic EL device according to the present invention, a material having a work function (4 eV or more) of a metal, an alloy, an electrically conductive compound and a mixture thereof is preferably used. Specific examples of such electrode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.

Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when pattern accuracy is not so high (about 100 μm or more) A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material.

  Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used.

  When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

"cathode"
On the other hand, as the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used.

Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃₎ mixture, indium, a lithium / aluminum mixture, and rare earth metals.

Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred.

  The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering.

  The sheet resistance as a cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm. In order to transmit the emitted light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the light emission luminance is improved, which is convenient.

  Moreover, after producing the said metal by the film thickness of 1 nm-20 nm to a cathode, the transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

《Support substrate》
As a support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) that can be used in the organic EL device according to the present invention, there is no particular limitation on the type of glass, plastic, etc., and it is transparent. Or opaque. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.

On the surface of the resin film, an inorganic film, an organic film, or a hybrid film of both may be formed. Water vapor permeability (25 ± 0.5 ° C.) measured by a method according to JIS K 7129-1992. , Relative humidity (90 ± 2)% RH) is preferably 0.01 g / (m ² · 24 h) or less, and further, oxygen measured by a method according to JIS K 7126-1987. A high barrier film having a permeability of 10 ⁻³ ml / (m ² · 24 h · MPa) or less and a water vapor permeability of 10 ⁻⁵ g / (m ² · 24 h) or less is preferable.

  As a material for forming the barrier film, any material may be used as long as it has a function of suppressing entry of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and organic material layers. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for forming the barrier film is not particularly limited. For example, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

  Examples of the opaque support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, and ceramic substrates.

  The external extraction efficiency at room temperature of light emission of the organic EL device of the present invention is preferably 1% or more, more preferably 5% or more.

  The external extraction quantum efficiency (%) is defined below.

External extraction quantum efficiency (%) = number of photons emitted to the outside of the organic EL element / number of electrons sent to the organic EL element × 100
In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor may be used in combination. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<Sealing>
As a sealing means used for this invention, the method of adhere | attaching a sealing member, an electrode, and a support substrate with an adhesive agent can be mentioned, for example.

  As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.

  Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz.

  Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone.

  Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

  In the present invention, a polymer film and a metal film can be preferably used because the element can be thinned.

Furthermore, the polymer film has a oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / (m ² · 24 h · MPa) or less, and a method according to JIS K 7129-1992. It is preferable that the water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured in (1) is 1 × 10 ⁻³ g / (m ² · 24 h) or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

  Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to. Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned.

  Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature to 80 degreeC is preferable.

  A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

  In addition, it is also preferable that the electrode and the organic layer are coated on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. .

  In this case, the material for forming the film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can. Further, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials.

  The method for forming these films is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster-ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

  In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum is also possible. Moreover, a hygroscopic compound can also be enclosed inside.

  Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

《Protective film, protective plate》
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided on the outer side of the sealing film on the side facing the support substrate with the organic layer interposed therebetween or on the sealing film. In particular, when the sealing is performed by the sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, and the like used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

《Light extraction》
The organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1) and can extract only about 15% to 20% of the light generated in the light emitting layer. It is generally said. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

  As a method of improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate and preventing total reflection at the transparent substrate and the air interface (US Pat. No. 4,774,435), A method of improving efficiency by providing a light collecting property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method of forming a reflective surface on a side surface of an element (Japanese Patent Laid-Open No. 1-220394), and light emission from a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the bodies (Japanese Patent Laid-Open No. 62-172691), a flat having a lower refractive index between the substrate and the light emitter than the substrate A method of introducing a layer (Japanese Patent Laid-Open No. 2001-202827), a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer and a light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951) Gazette).

  In the present invention, these methods can be used in combination with the organic EL device of the present invention. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, transparent A method of forming a diffraction grating between any layers of the electrode layer and the light emitting layer (including between the substrate and the outside) can be suitably used.

  In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

  When a medium having a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower.

  Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Further, it is preferably 1.35 or less.

  The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate.

  The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency. This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction and second-order diffraction. Of these, light that cannot be emitted due to total reflection between layers, etc. is diffracted by introducing a diffraction grating into any layer or medium (inside a transparent substrate or transparent electrode). I want to take it out.

  The introduced diffraction grating desirably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. Therefore, the light extraction efficiency does not increase so much. However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated.

  At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium.

  The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

<Condenser sheet>
The organic EL device of the present invention is processed on the light extraction side of the substrate so as to provide, for example, a microlens array structure, or combined with a so-called condensing sheet, for example, with respect to a specific direction, for example, the light emitting surface By condensing in the front direction, the luminance in a specific direction can be increased.

  As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 μm to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the base material may be formed by forming a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded and the pitch is changed randomly. Other shapes may be used.

  Moreover, in order to control the light emission angle from a light emitting element, you may use together a light diffusing plate and a film with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

<< Method for Producing Organic EL Element of Lighting Device of Present Invention >>
As an example of a method for producing an organic EL element included in the lighting device of the present invention, a method for producing an organic EL element comprising an anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode is used. explain.

  First, a desired electrode material, for example, a thin film made of an anode material is formed on a suitable substrate so as to have a film thickness of 1 μm or less, preferably 10 nm to 200 nm, to form an anode.

  Next, an organic compound thin film of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a hole blocking layer, which are organic EL element materials, is formed thereon.

  As a method for forming each of these layers, there are a vapor deposition method, a wet process (spin coating method, casting method, ink jet method, printing method) and the like as described above, but it is easy to obtain a homogeneous film and it is difficult to generate pinholes. In view of the above, film formation by a coating method such as a spin coating method, an ink jet method, or a printing method is preferable in the present invention.

  Examples of the liquid medium for dissolving or dispersing the organic EL material according to the present invention include ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, toluene, xylene, and mesitylene. Aromatic hydrocarbons such as cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin, and dodecane, and organic solvents such as DMF and DMSO can be used. Moreover, as a dispersion method, it can disperse | distribute by dispersion methods, such as an ultrasonic wave, high shear force dispersion | distribution, and media dispersion | distribution.

  After these layers are formed, a thin film made of a cathode material is formed thereon by 1 μm or less, preferably by a method such as vapor deposition or sputtering so that the film thickness is in the range of 50 nm to 200 nm. By providing, a desired organic EL element can be obtained.

  Further, it is possible to reverse the production order, and to produce the cathode, the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order. When a DC voltage is applied to the multicolor display device thus obtained, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is a schematic diagram which shows an example of the organic EL element used for the illuminating device of this invention. It is the schematic of the illuminating device of this invention. It is the schematic of the illuminating device of this invention. An example of the emission spectrum of a white type organic EL element is shown. An example of the emission spectrum of a white type organic EL element is shown. An example of the emission spectrum of a blue phosphorescence emission dopant is shown. An example of the emission spectrum of a green phosphorescence emission dopant is shown. An example of the emission spectrum of a red phosphorescence emission dopant is shown. An example of the emission spectrum of a blue fluorescence emission dopant is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Organic EL element 102 Glass cover 105 Cathode 106 Organic EL layer 107 Glass substrate with a transparent electrode 108 Nitrogen gas 109 Water catching agent

Claims (11)

An organic electroluminescence element having at least an anode and a cathode on a support substrate and having at least one light emitting layer between the anode and the cathode, and the organic electroluminescence element contains at least two kinds of light emitting materials And an illuminating device having light emission of the shortest wavelength of the luminescent material as an optical communication means. The illumination device according to claim 1, wherein the light having the shortest wavelength is fluorescent light emission. 3. The illumination device according to claim 1, wherein a difference in emission maximum wavelength between the light having the shortest wavelength and the light having the next shortest wavelength is 20 nm to 250 nm. The lighting device according to any one of claims 1 to 3, wherein at least one of the light emission of the light emitting material is a phosphorescent compound. The illumination according to any one of claims 1 to 4, wherein the next shortest wavelength light emission is phosphorescence emission, and the emission maximum wavelength of the phosphorescence emission is in a range of 460 nm to 480 nm. apparatus. The illumination according to any one of claims 1 to 5, wherein at least one of the phosphorescent compounds is an orthometalated complex having a partial structure represented by the following general formula (1). apparatus.

[Wherein R ₁ represents a substituent. Z represents a nonmetallic atom group necessary for forming a 5- to 7-membered ring. n1 represents the integer of 0-5. B _{1 to} B ₅ each represent a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom, and at least one represents a nitrogen atom. M ₁ represents a transition metal element of Group 8 to Group 10 in the periodic table. X ₁ and X ₂ each represent a carbon atom, a nitrogen atom, or an oxygen atom, and L ₁ represents an atomic group that forms a bidentate ligand together with X ₁ and X ₂ . m1 represents an integer of 1, 2 or 3, m2 represents an integer of 0, 1 or 2, and m1 + m2 is 2 or 3. ] 7. The layer according to claim 1, wherein a layer containing at least one light emitting material that emits light having the shortest wavelength and a layer containing at least one light emitting material are provided separately. The lighting device according to claim 1. The illumination device according to any one of claims 1 to 7, further comprising a light receiving unit as a configuration, wherein a detection wavelength of the light receiving unit is set to less than 450 nm. 9. The structure according to claim 1, further comprising: a transmission unit configured to transmit both a low frequency band of less than 1 MHz and a high frequency band of 1 MHz or more from the same light emitting element. The lighting device according to claim 1. 10. The signal reception of the low frequency band is detected in a wavelength region of 450 nm or more, and the signal reception of the high frequency band is detected in a wavelength region of less than 450 nm. The lighting device described. A white illumination device comprising the illumination device according to claim 1.

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