Light-emitting apparatus, electronic appliance, and illumination apparatus

Abstract

To provide a light-emitting apparatus with low consumption power.SOLUTION: A light-emitting apparatus includes a first light-emitting device and a first color conversion layer. The first light-emitting device includes an anode, a cathode, and an EL layer existing between the anode and the cathode. The EL layer includes a layer containing a material whose refractive index to light with a wavelength of 467 nm is 1.75 or less. The first color conversion layer includes a first material that absorbs and emits light. The light emission from the first light-emitting device is delivered to the first color conversion layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] One aspect of the present invention is an organic compound, a light-emitting element, a light-emitting device, a display module, and a lighting device. The present invention relates to a light module, a display device, a light-emitting device, an electronic device, a lighting device and an electronic device. Note that one embodiment of the present invention is not limited to the above technical field. The technical field of one aspect relates to an article, a method, or a manufacturing method. One aspect of the present invention is a process, machine, manufacture, or composition. Therefore, the present invention more specifically disclosed herein The technical field of one embodiment of the present invention is a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a lighting device, device, power storage device, storage device, imaging device, driving method thereof, or manufacturing method thereof One example can be mentioned. [Background technology]

[0002] Electroluminescence (EL) using organic compounds The practical application of light-emitting devices (organic electroluminescence devices) that utilize these The basic structure of a light-emitting device is an organic compound layer (EL layer) containing a light-emitting material between a pair of electrodes. A voltage is applied to this device to inject carriers, and the carriers By utilizing the recombination energy, light can be emitted from the light-emitting material.

[0003] Since such light-emitting devices are self-emitting, when they are used as pixels in a display, Compared to flat panel displays, it has the advantage of being highly visible and not requiring a backlight. The light-emitting device is suitable for use as a spray element. Another major advantage of the sensor is that it can be made thin and lightweight. This is also one of its characteristics.

[0004] In addition, these light-emitting devices can form light-emitting layers continuously in two dimensions. This is the same as point light sources such as incandescent light bulbs and LEDs, This is a feature that is difficult to obtain with linear light sources such as fluorescent lamps, so it is considered to be a surface light source that can be applied to lighting, etc. It is also highly useful as a tool.

[0005] Displays and lighting devices using such light-emitting devices are suitable for use in a wide range of electronic devices. However, research and development is ongoing to develop light emitting devices with better properties.

[0006] One of the issues that is often mentioned when talking about organic EL devices is light extraction. In particular, attenuation due to reflection caused by differences in the refractive index of adjacent layers is This is a major factor in reducing the efficiency of the device. A configuration has been proposed in which a layer made of a low refractive index material is formed on the substrate (for example, Patent Document 1 and Non-Patent Document 2). (See Patent Document 1).

[0007] A light emitting device having this configuration has a higher light extraction efficiency than a light emitting device having a conventional configuration. This allows the production of a light-emitting device with high external quantum efficiency. A layer of refractive index can be placed inside the EL layer without adversely affecting other important properties of the light-emitting device. It is not easy to form such a material because it requires a low refractive index, high carrier transport properties, and This is because there is a trade-off between the reliability and the cost of using it in a light-emitting device. The carrier transport properties and reliability of organic compounds are due to the presence of unsaturated bonds. This is because organic compounds that are large and have many unsaturated bonds tend to have a high refractive index. do.

[0008] On the other hand, displays using a color conversion method have been put to practical use. By irradiating a material that exhibits luminescence with light from a light-emitting device, it becomes possible to produce light of the desired color. A color conversion display simply converts the light from a light-emitting device into Photoluminescence efficiency compared to color filter type displays that cut Although it depends on the device, it is said that it is easier to obtain displays with less energy loss and lower power consumption. It has the following characteristics. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2014-207356 A [Non-Patent Document 1] Jaeho Lee and 12 others, "Synergetic electrode architecture for efficient graphene-based flexible organic light-emitting diodes", Nature COMMUNICATIONS, June 2, 2016, DOI:10.1038 / ncomms11791 Summary of the Invention [Problem to be solved by the invention]

[0010] In view of the above, an object of one embodiment of the present invention is to provide a novel light-emitting device. The object of the present invention is to provide a light emitting device having good efficiency or a light emitting device having good life. Another object of the present invention is to provide a light emitting device with a low driving voltage. .

[0011] In another embodiment of the present invention, a highly reliable electronic device or display device is provided. Another embodiment of the present invention is an electronic device or The present invention aims to provide a display device.

[0012] It is sufficient for the present invention to solve any one of the above problems. [Means for solving the problem]

[0013] One embodiment of the present invention is a light-emitting device having a first light-emitting device and a first color conversion layer. The first light emitting device is disposed between an anode and a cathode. and an EL layer having a refractive index of 1.75 or less for light having a wavelength of 467 nm. The first color conversion layer has a layer containing a material which is a light emitting device in which light emitted from the first light emitting device is irradiated onto the first color conversion layer. It is.

[0014] Another embodiment of the present invention is a light-emitting device having a first light-emitting device and a first color conversion layer. 13. An apparatus, comprising: a first light-emitting device having an anode, a cathode, and a light-emitting diode (LED) disposed between the anode and the cathode; and an EL layer positioned therebetween, the EL layer having a refractive index of 1 0.75 or less, and the first color conversion layer contains a first substance that absorbs light and emits light. a light emitting device in which light emitted from the first light emitting device is irradiated onto the first color conversion layer. It is.

[0015] Another embodiment of the present invention is a light-emitting device having a first light-emitting device and a first color conversion layer. An optical device, the first light emitting device comprising an anode, a cathode, the anode, the cathode, and an EL layer located between the light-emitting layer and the hole-injecting layer, the EL layer having a light-emitting layer and a hole-injecting layer. The hole injection layer is provided in contact with the anode, and the hole injection layer is resistant to light having a wavelength of 467 nm. The first color conversion layer contains an organic compound having a refractive index of 1.75 or less, and the first color conversion layer absorbs light. a first material that emits light according to a first color conversion; and the light emitted from the first light-emitting device is The light emitting device is adapted to irradiate the layer.

[0016] Alternatively, another aspect of the present invention is, in the above-mentioned configuration, An organic compound having a refractive index of 1.75 or less includes a first aromatic ring, a second aromatic ring, and a third aromatic ring. a monoamine compound having an aromatic ring, The third aromatic ring is bonded to a nitrogen atom of the monoamine compound, and the total number of carbon atoms in the molecule is The ratio of carbon atoms forming bonds with sp3 hybrid orbitals is 23% to 55%. It is a light-emitting device that is an organic compound.

[0017] Alternatively, another aspect of the present invention is, in the above-mentioned configuration, The organic compound having a refractive index of 1.75 or less is an organic compound represented by the following general formula (G1): It is a light-emitting device.

[0018] [ka]

[0019] In the above general formula (G1), Ar1 , Ar 2 each independently represents a benzene ring or or two or three benzene rings bonded together. 1 , Ar 2 One or both of the carbons are 1 to 12 carbon atoms in which the carbons form bonds only with sp3 hybrid orbitals. Ar 1 and Ar 2 The hydrocarbon group bonded to The total number of carbon atoms contained in the aryl group is 8 or more, and 1 and Ar 2 Binds to at least one of The total number of carbon atoms contained in the hydrocarbon group is 6 or more. 1 or Ar 2 Before When the hydrocarbon group contains multiple linear alkyl groups having 1 or 2 carbon atoms, the linear alkyl groups The alkyl chain groups may be bonded to each other to form a ring. R 1 and R 2 Each independently represents an alkyl group having 1 to 4 carbon atoms. 1 and R 2 may be bonded to each other to form a ring. 3 is an alkyl group having 1 to 4 carbon atoms where u is an integer from 0 to 4.

[0020] Another embodiment of the present invention is a light-emitting device having a first light-emitting device and a first color conversion layer. 13. An apparatus, comprising: a first light-emitting device having an anode, a cathode, and a light-emitting diode (LED) disposed between the anode and the cathode; and an EL layer located between the EL layer and the light-emitting layer, the EL layer having a light-emitting layer and an electron-transporting layer, the electron The electron transport layer is located between the light emitting layer and the cathode, and the electron transport layer is a 467 nm wavelength The first color conversion layer has a material having a refractive index of 1.75 or less for light absorbing and a first material that emits light in response to a first color change, the light emitted from the first light-emitting device being It is a light-emitting device that irradiates the substrate.

[0021] Alternatively, in the above-mentioned configuration, the material having a refractive index of 1.75 or less is A mixed material of an organic compound having an electron transport property and an inorganic compound, The light emitting device is an alkali metal fluoride or an alkaline earth metal fluoride.

[0022] Alternatively, another embodiment of the present invention is the above-mentioned structure, wherein the inorganic compound is an alkali metal. and a concentration of the inorganic compound in the electron transport layer is 50 vol % or more. be.

[0023] Alternatively, another embodiment of the present invention is the above-mentioned structure, wherein the inorganic compound is an alkali metal. The concentration of the inorganic compound in the electron transport layer is 50 vol % or more and less than 95 vol %. It is a light emitting device.

[0024] Alternatively, in the above-mentioned configuration, the inorganic oxide in the electron transport layer is The concentration of the compound is 20 vol % or more in the light emitting device.

[0025] Another embodiment of the present invention is a liquid crystal display device having the above structure, further comprising: a first light-emitting device; a light emitting device having a first light emitting device and a second light emitting layer, The device has an anode and an EL layer located between the cathode, the EL layer including a hole injection layer and a light emitting layer. a hole injection layer located between the anode and the light emitting layer, and an electron transport layer. The electron transport layer is located between the light emitting layer and the cathode, and the hole injection layer is The electron transport layer comprises an organic compound having a refractive index of 1.75 or less for light having a wavelength of 7 nm. The first color conversion element has a material having a refractive index of 1.75 or less for light having a wavelength of 467 nm. The layer includes a first material that absorbs light and emits light, and the light emitted from the first light-emitting device is A light emitting device is provided for irradiating the first color conversion layer.

[0026] Alternatively, another embodiment of the present invention is a semiconductor device having the above-described structure, The light emitting device has an emission spectrum with a peak wavelength of 440 nm to 520 nm. .

[0027] Another embodiment of the present invention is a light-emitting device having a first light-emitting device and a first color conversion layer. An optical device, the first light emitting device comprising an anode, a cathode, the anode, the cathode, and an EL layer located between the hole injection layer, the light emitting layer, and the electron transport layer. The hole injection layer is located between the anode and the light emitting layer, and the electron transport layer is The hole injection layer is located between the light emitting layer and the cathode, and is resistant to light having a wavelength of 467 nm. The electron transport layer has an organic compound having a refractive index of 1.75 or less with respect to a wavelength of 467 nm. The first color conversion layer has a refractive index of 1.75 or less for the light of a first material that emits light, and light emitted from the first light-emitting device is reflected by the first color conversion layer; It is a light-emitting device that irradiates light to the

[0028] Alternatively, another embodiment of the present invention is the above-mentioned structure, wherein the first substance is a quantum dot. It is a light-emitting device.

[0029] Alternatively, in the above-described structure, the first light-emitting device may be a microresonator. The light emitting device has a structure.

[0030] Alternatively, in the above-described configuration, the light-emitting device further includes a second light-emitting The second light-emitting device includes an optical device, a third light-emitting device, and a second color conversion layer. the first light emitting device and the third light emitting device have the same structure as the first light emitting device, The second color conversion layer has a second substance that absorbs light and emits light, and the emission spectrum of the first substance is The peak wavelength of the spectrum of the second substance is different from the peak wavelength of the emission spectrum of the second substance. The light emitted from the second light emitting device is irradiated onto the second color conversion layer.

[0031] Alternatively, another embodiment of the present invention is a semiconductor device having the above-mentioned structure, wherein the second substance is a quantum dot. It is a light-emitting device.

[0032] Alternatively, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: The peak wavelength is in the range of 500 nm to 600 nm, and the peak of the emission spectrum of the second substance is It is a light-emitting device with a peak wavelength of 600 nm to 750 nm.

[0033] Alternatively, in another aspect of the present invention, in the above-described configuration, the light-emitting device further includes a fourth light-emitting element. a fourth light-emitting device and a third color conversion layer, The third color conversion layer has a third substance that absorbs light and emits light. the third substance has an emission spectrum having a peak wavelength of 560 nm to 610 nm; a light-emitting device in which light emitted from the fourth light-emitting device is irradiated onto the third color conversion layer; .

[0034] Alternatively, another embodiment of the present invention is a semiconductor device having the above-mentioned structure, wherein the third substance contains a rare earth element. It is a light-emitting device.

[0035] Alternatively, in the above-mentioned structure, the rare earth element is europium, cerium, The light emitting device is preferably made of at least one of chromium and yttrium.

[0036] Alternatively, another embodiment of the present invention is a semiconductor device having the above-mentioned structure, wherein the third substance is a quantum dot. It is a light-emitting device.

[0037] Alternatively, another aspect of the present invention is a light emitting device having the above-mentioned structure, This is a light emitting device with two peaks in its light spectrum.

[0038] Alternatively, another aspect of the present invention is a light emitting device having the above-mentioned structure, This is a light-emitting device that emits white light.

[0039] Alternatively, in the above-described structure, the light-emitting device may include a plurality of light-emitting layers. The light emitting device has the following features.

[0040] Alternatively, in the above structure, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: A light-emitting device having a biolayer.

[0041] Alternatively, in the above-described structure, the first light-emitting device may be configured to emit blue light. It is a light emitting device exhibiting the above.

[0042] Alternatively, in the above-described configuration, the light-emitting device may further include a color filter. the first color conversion layer is located between the first light emitting device and the color filter. It is a light-emitting device that is placed

[0043] Another embodiment of the present invention is a light-emitting device including any one of the above-described light-emitting devices, a sensor, and an operation button. The electronic device has a touch panel, a speaker, or a microphone.

[0044] Another embodiment of the present invention is a light-emitting device including any one of the above light-emitting devices, a transistor, and Alternatively, the light emitting device may include a substrate.

[0045] Another embodiment of the present invention is a light-emitting device including any one of the above light-emitting devices and a housing. It is a lighting device.

[0046] In this specification, the term "light-emitting device" includes an image display device using a light-emitting device. In addition, a connector, such as anisotropic conductive film or TCP (Tape) Module with Carrier Package attached, printed on TCP Modules with wiring boards or light-emitting devices with COG (Chip On Glass) s) A module in which an IC (integrated circuit) is directly mounted may also be included in the category of light-emitting device. Furthermore, lighting fixtures and the like may include a light-emitting device. Effect of the Invention

[0047] According to one embodiment of the present invention, a novel light-emitting device having high emission efficiency can be provided. It is possible to provide an optical device. Alternatively, it is possible to provide a light emitting device having a long life. Alternatively, a light emitting device with a low driving voltage can be provided.

[0048] Another embodiment of the present invention is to provide an electronic device or a display device with high reliability. Another embodiment of the present invention is a low-power electronic device or display device. can be provided respectively.

[0049] The description of these effects does not preclude the existence of other effects. An embodiment does not necessarily have to have all of these effects. Effects other than these may also be included. The above is self-evident from the description, drawings, claims, etc. Other effects can be extracted from the claims and other descriptions. [Brief description of the drawings]

[0050] [Figure 1] 1(A), (B), and (C) are conceptual diagrams of a light-emitting device. [Diagram 2] 2(A), (B), and (C) are schematic diagrams of light-emitting devices. [Diagram 3] FIG. 3 is a schematic diagram of a light emitting device. [Figure 4] 4(A), (B), and (C) are conceptual diagrams of a light-emitting device. [Diagram 5] 5(A), (B), and (C) are conceptual diagrams of a light-emitting device. [Figure 6] 6(A) and (B) are conceptual diagrams of a passive matrix type light emitting device. [Figure 7] 7(A) and (B) are conceptual diagrams of an active matrix type light emitting device. [Figure 8] 8(A) and (B) are conceptual diagrams of an active matrix type light emitting device. [Figure 9] FIG. 9 is a conceptual diagram of an active matrix type light emitting device. [Figure 10] 10(A), (B1), (B2), and (C) are diagrams showing electronic devices. [Figure 11] 11(A), (B), and (C) are diagrams showing electronic devices. [Figure 12] FIG. 12 is a diagram showing an in-vehicle display device and a lighting device. [Figure 13] 13(A) and (B) are diagrams showing electronic devices. [Figure 14] 14(A), (B), and (C) are diagrams showing electronic devices. [Figure 15] FIG. 15 shows data obtained by measuring the refractive index of dchPAF. [Figure 16] FIG. 16 shows the data obtained by measuring the refractive index of chBichPAF. [Figure 17] FIG. 17 shows data obtained by measuring the refractive index of dchPASchF. [Figure 18] FIG. 18 shows data obtained by measuring the refractive index of chBichPASchF. [Figure 19] FIG. 19 shows data obtained by measuring the refractive index of SchFB1chP. [Figure 20] FIG. 20 shows the data obtained by measuring the refractive index of mmtBuBichPAF. [Figure 21] FIG. 21 shows data obtained by measuring the refractive index of dmmtBuBiAF. [Figure 22] FIG. 22 shows data obtained by measuring the refractive index of mmtBuBimmtBuPAF. [Diagram 23] FIG. 23 shows data obtained by measuring the refractive index of dchPAPrF. [Figure 24] FIG. 24 shows data obtained by measuring the refractive index of mmchBichPAF. [Diagram 25] FIG. 25 shows data obtained by measuring the refractive index of mmtBumTPchPAF. [Figure 26] FIG. 26 shows data obtained by measuring the refractive index of CdoPchPAF. [Figure 27] FIG. 27 shows the emission spectrum used in the calculation. [Figure 28] FIG. 28 is a diagram showing the results of calculating the relationship between the refractive index of the color conversion layer (QD layer) and the amount of light that reaches the color conversion layer. [Figure 29] FIG. 29 is a graph showing the luminance-current density characteristics of the light-emitting device 1 and the light-emitting device 2. As shown in FIG. [Diagram 30] FIG. 30 is a graph showing the current efficiency-luminance characteristics of the light-emitting device 1 and the light-emitting device 2. As shown in FIG. [Diagram 31]FIG. 31 is a diagram showing the luminance-voltage characteristics of the light-emitting device 1 and the light-emitting device 2. As shown in FIG. [Diagram 32] FIG. 32 is a diagram showing the current-voltage characteristics of the light-emitting device 1 and the light-emitting device 2. In FIG. [Diagram 33] FIG. 33 is a graph showing the blue index-luminance characteristics of the light-emitting device 1 and the light-emitting device 2. In FIG. [Diagram 34] FIG. 34 shows the emission spectra of the light-emitting device 1 and the light-emitting device 2. As shown in FIG. [Diagram 35] FIG. 35 shows the refractive indices of dchPAF and PCBBiF. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0051] Hereinafter, the embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the above description, and the form and details are not limited thereto without departing from the spirit and scope of the present invention. It will be readily understood by those skilled in the art that various modifications may be made. It should not be construed as being limited to the description of the embodiment modes.

[0052] (Embodiment 1) In recent years, color conversion technology using quantum dots (QD) has become popular in LCD displays. QDs are semiconductor nanocrystals with a size of a few nm. 1×10 3 1×10 6 QDs are made up of about 100 atoms. As a result of the excitons being confined inside, their energy states become discrete, In addition, the energy shift depends on the size. Since the emission wavelength differs depending on the size of the QDs, the size of the QDs used can be changed. This makes it possible to easily adjust the emission wavelength.

[0053] In addition, QDs have a narrow emission spectrum peak width because their discrete nature limits phase relaxation. It is possible to obtain light emission with good color purity. In other words, by using a color conversion layer using QDs, Therefore, it is possible to obtain light emission with high color purity, and it is compatible with the BT.2020 and BT.210 standards. It is also possible to obtain light emission that covers the Rec. 2020 color gamut, which is standardized by the 1.0 standard. be.

[0054] The color conversion layer using QDs is similar to the color conversion layer using organic light-emitting materials. The light-emitting device absorbs light emitted from the source and re-emits it through photoluminescence. It converts light into light with a longer wavelength. Therefore, it is used as a color conversion layer for display purposes. When doing so, blue, which has the shortest wavelength of the three primary colors required to reproduce full color, is used. The configuration employs light obtained from a light-emitting device, and green and red light is obtained through color conversion.

[0055] That is, the characteristics of the blue light-emitting device used in the display that adopts the color conversion method This dominates many of the device's characteristics, resulting in a blue-emitting device with better characteristics. What is required is...

[0056] As shown in FIG. 1A, a light-emitting device according to one embodiment of the present invention includes a light-emitting device 207 and a color conversion layer. The pixel 208 has a light emitting device 205, and the light emitted from the light emitting device 207 is color converted The light emitting device 207 is configured such that light is incident on the first electrode 201 and the second electrode 205. The EL layer 202 is disposed between the electrode 203. The color conversion layer 205 includes quantum dots. It is preferable that the photodiode has a function of absorbing incident light and emitting light of a predetermined wavelength. When the color conversion layer 205 contains quantum dots, the peak width of the emission spectrum is narrow, Light emission with good color purity can be obtained.

[0057] The color conversion layer 205 has a function of absorbing incident light and emitting light of a predetermined wavelength. The substance that has the function of emitting light of the specified wavelength is phosphatase. It is possible to use various luminescent materials, such as inorganic materials that exhibit luminescence and organic materials. In particular, quantum dots (QDs), which are inorganic materials, have a peak in the emission spectrum as mentioned above. It has a narrow wavelength band and emits light with good color purity. In addition, it is an inorganic material, so it is inherently stable. It is also preferable because it has excellent thermal conductivity and a theoretical internal quantum efficiency of nearly 100%.

[0058] The color conversion layer 205 containing quantum dots is formed by applying a solvent in which quantum dots are dispersed, drying, and baking. It can also be formed by forming a semiconductor device with quantum dots dispersed therein. The different colors can be applied by droplet ejection methods such as inkjet or printing. The coating is applied to the surface to be formed, and then the coating is fixed by drying, baking, solidification, etc., and then the coating is applied to the surface by photolithography, etc. This can be achieved by etching using a material such as a silicon dioxide gas.

[0059] Quantum dots include group 14 elements, group 15 elements, group 16 elements, and multiple group 14 elements. Compounds consisting of elements belonging to groups 4 to 14 and group 16, compounds consisting of elements belonging to group 2 Compounds of elements from Group 13 and Group 15, compounds of elements from Group 13 and Compounds with Group 17 elements, compounds with Group 14 and Group 15 elements, compounds with Group 11 and Group 1 Compounds with group 7 elements, iron oxides, titanium oxides, chalcogenide spinels, various semiconductors clusters, and nano-sized particles such as metal halide perovskites. .

[0060] Specifically, cadmium selenide (CdSe), cadmium sulfide (CdS), cadmium telluride (CdTe) Cadmium (CdTe), zinc selenide (ZnSe), zinc oxide (ZnO), zinc sulfide (Z nS), zinc telluride (ZnTe), mercury sulfide (HgS), mercury selenide (HgSe), Mercury telluride (HgTe), indium arsenide (InAs), indium phosphide (InP) , Gallium arsenide (GaAs), Gallium phosphide (GaP), Indium nitride (InN), Gallium nitride (GaN), indium antimonide (InSb), gallium antimonide (GaSb), aluminum phosphide (AlP), aluminum arsenide (AlAs), anti Aluminum monide (AlSb), lead(II) selenide (PbSe), lead(II) telluride ) (PbTe), lead(II) sulfide (PbS), indium selenide (In2Se3), Indium tetrafluoride (In2Te3), indium sulfide (In2S3), gallium selenide (Ga2Se3), arsenic(III) sulfide (As2S3), arsenic(III) selenide (As 2Se3), arsenic(III) telluride (As2Te3), antimony(III) sulfide (S b2S3), antimony selenide(III) (Sb2Se3), antimony telluride(I II) (Sb2Te3), bismuth sulfide (III) (Bi2S3), bismuth selenide ( III) (Bi2Se3), bismuth(III) telluride (Bi2Te3), silicon (S i), silicon carbide (SiC), germanium (Ge), tin (Sn), selenium (Se), Te, Boron (B), Carbon (C), Phosphorus (P), Boron Nitride (BN), Boron Phosphide Arsenic (BP), boron arsenide (BAs), aluminum nitride (AlN), aluminum sulfide (Al2S3), barium sulfide (BaS), barium selenide (BaSe), barium telluride BaTe, calcium sulfide (CaS), calcium selenide (CaSe), Calcium tetroxide (CaTe), beryllium sulfide (BeS), beryllium selenide (Be Se), Beryllium Telluride (BeTe), Magnesium Sulfide (MgS), Magnesium Selenide Magnesium (MgSe), Germanium sulfide (GeS), Germanium selenide (GeSe ), germanium telluride (GeTe), tin(IV) sulfide (SnS2), tin(II) sulfide (SnS), tin(II) selenide (SnSe), tin(II) telluride (SnTe), oxide Lead(II) (PbO), copper(I) fluoride (CuF), copper(I) chloride (CuCl), copper bromide (I) (CuBr), copper(I) iodide (CuI), copper(I) oxide (CuO), selenide Copper(I) (CuSe), nickel(II) oxide (NiO), cobalt(II) oxide (C oO), cobalt(II) sulfide (CoS), iron(II) tetroxide (Fe3O4), iron(II) sulfide (FeS), manganese(II) oxide (MnO), molybdenum(IV) sulfide (MoS2), Vanadium(II) oxide (VO), vanadium(IV) oxide (VO2), tungsten oxide Tantalum(IV) (WO2), Tantalum(V) oxide (Ta2O5), Titanium oxide (TiO2, T i2O5, Ti2O3, Ti5O9, etc.), zirconium oxide (ZrO2), silicon nitride (Si3N4), germanium nitride (Ge3N4), aluminum oxide (Al2O3), Barium titanate (BaTiO3), a compound of selenium, zinc and cadmium (CdZnSe ), indium arsenic phosphorus compound (InAsP), cadmium selenium sulfur compound Cadmium, selenium and tellurium compound (CdSeS), cadmium, selenium and tellurium compound (CdSeTe), indium and gallium and arsenic compounds (InGaAs), and indium, gallium and selenium compounds ( InGaSe), indium selenium and sulfur compound (InSeS), copper and indium Examples of such compounds include sulfur compounds (e.g., CuInS2), and combinations thereof. However, the present invention is not limited to these. In addition, the composition is expressed in any ratio, so-called alloy type quantum dots. For example, CdS x Se (1-x) (x is any number between 0 and 1) The alloy quantum dots that are used in this study can change the emission wavelength by varying x, so they can emit blue light. This is an effective means of obtaining colored light.

[0061] Quantum dot structures include core type, core-shell type, and core-multishell type. Either of these may be used, but it is also possible to cover the core with another inorganic material with a wider band gap. By forming a shell with the material, defects and dangling bonds on the nanocrystal surface can be eliminated. This can reduce the effect of the core It is preferable to use core-shell or core-multishell quantum dots. Examples include zinc sulfide (ZnS) and zinc oxide (ZnO).

[0062] In addition, quantum dots have a high proportion of surface atoms, making them highly reactive and prone to aggregation. Therefore, a protective agent or a protective group is attached to the surface of the quantum dot. It is preferable that the protecting agent is attached or the protecting group is provided, It can prevent aggregation and increase solubility in solvents. It also reduces reactivity and improves electrical stability. It is also possible to improve the quality of the reaction. Examples of the protecting agent (or protecting group) include polyoxyethylene. Diethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene Polyoxyethylene alkyl ethers such as oleyl ether, tripropyl phosphide, phosphine, tributylphosphine, trihexylphosphine, trioctylphosphine, etc. Trialkylphosphines, Polyoxyethylene n-octylphenyl ether, Polyoxyethylene Polyoxyethylene alkylphenyl ethers such as diethylene n-nonylphenyl ether amines, tri(n-hexyl)amine, tri(n-octyl)amine, tri(n-decyl)amine Tertiary amines such as amines, tripropylphosphine oxide, tributylphosphine oxide oxide, trihexylphosphine oxide, trioctylphosphine oxide, tridecylphosphine oxide organic phosphorus compounds such as arylphosphine oxide, polyethylene glycol dilaurate, poly Polyethylene glycol diesters such as ethylene glycol distearate, organic nitrogen compounds, such as nitrogen-containing aromatic compounds, such as lysine, lutidine, collidine, and quinolines; Hexylamine, octylamine, decylamine, dodecylamine, tetradecylamine , hexadecylamine, octadecylamine and other aminoalkanes, dibutyl sulfide Dialkyl sulfides such as dimethyl sulfoxide and dibutyl sulfoxide Organic sulfur compounds such as alkyl sulfoxides, sulfur-containing aromatic compounds such as thiophene, palmitate, etc. Higher fatty acids such as carboxylic acid, stearic acid, and oleic acid, alcohols, sorbitan fatty acid esters, Polyesters, fatty acid modified polyesters, tertiary amine modified polyurethanes, polyethyleneimine Examples include fluorinated substances.

[0063] When the substance contained in the color conversion layer 205 is QD, the QD emits light with wavelengths from near its own emission wavelength to short wavelengths. On the long side, it has a continuous absorption spectrum in which the absorption intensity is higher for shorter wavelengths. In the case of a display that requires emission colors, the emission devices of the respective color pixels The central material can be a common material, and as shown in Figure 1(B), a light-emitting device is used for each pixel color. This eliminates the need for separate production, and allows the light emitting device to be manufactured at relatively low cost.

[0064] In FIG. 1B, a pixel that emits three colors of light, blue, green, and red, is shown as an example. The first pixel 208B emits color light. The electrodes 203 are anode and cathode. Alternatively, one of the electrodes may be a reflective electrode and the other may be a semi-transparent semi-reflective electrode. Illustrated are a second pixel 208G exhibiting red light emission, and a third pixel 208R exhibiting red light emission. The first electrode 201G and the second electrode 203, the first electrode 201R and In FIG. 1B, the first electrodes 201B, 201G and The first electrode 201R is a reflective electrode and an anode, and the second electrode 203 is a semi-transparent semi-reflective electrode. The first electrode 201B to the first electrode 201R are formed on the insulator 200. In addition, a black matrix is ​​placed between each pixel to prevent light from mixing with adjacent pixels. It is preferable that the black matrix 206 is provided. It may also serve as a bank when forming a color conversion layer by a jet method or the like.

[0065] In addition, FIG. 1(C) shows a pixel that emits four colors of light: blue, green, red, and white. The fourth pixel 208W emits white light. The fourth pixel 208W includes a first electrode 201W and It has a second electrode 203, one of which is an anode and the other is a cathode. Alternatively, one of them may be a reflective electrode and the other may be a semi-transparent semi-reflective electrode. The electrode 201W is formed on the insulator 200. In addition, in order to prevent light from mixing with adjacent pixels, For this reason, it is preferable to provide a black matrix 206 between the pixels. The rack matrix 206 also serves as a bank when forming a color conversion layer by the inkjet method or the like. It's okay to sleep.

[0066] The first electrodes 201B, 201G, 201C in the first pixel 208B to the fourth pixel 208W An EL layer 202 is sandwiched between the second electrode 203 and the electrodes 201R and 201W. 202 may be common to the first pixel 208B to the fourth pixel 208W or may be separate. However, it is easier to manufacture and more cost-effective to have a common pixel for multiple pixels. In addition, the EL layer 202 is usually composed of multiple layers with separate functions. The signal may be shared among several pixels, and a part of the signal may be independent for each pixel.

[0067] The first pixel 208B to the fourth pixel 208W are each formed of a first electrode, a second electrode, and an EL layer. The first light emitting device 207B, the second light emitting device 207G, and the third light emitting device The fourth light emitting device 207R and the fourth light emitting device 207W are also included. In (C) and (D), the first pixel 208B to the fourth pixel 208W have a common EL layer 202. The above configuration is exemplified.

[0068] The first light emitting device 207B to the fourth light emitting device 207W are connected to a first electrode and a second electrode. A micro-resonant structure is achieved by using one of the electrodes as a reflective electrode and the other as a semi-transparent semi-reflective electrode. The wavelength at which resonance can be achieved can be determined by the wavelength of the reflective electrode. The optical distance 209 between the surface of the electrode and the surface of the semi-transmissive / semi-reflective electrode is determined. By setting the wavelength to be resonated as λ, and multiplying it by an integer number of λ / 2, the light of wavelength λ can be amplified. The optical distance 209 is the distance between the hole injection layer, the hole transport layer, and a part of the electrode of the EL layer. This can be adjusted by forming a transparent electrode layer on the reflective electrode. In the light-emitting device of FIG. 1(C), the EL layer is formed of the first light-emitting device 207B to the fourth light-emitting device 207C. The luminescence center material is the same for both the 207W and 201W, so the optical properties of the light-emitting device are The distance 209 is common to the first pixel 208B to the fourth pixel 208W, and therefore can be easily formed. In addition, when the EL layer 202 is separately formed for each pixel, The optical distance 209 may be formed in accordance with the light from the layer.

[0069] A protective layer 204 is provided on the second electrode 203. In addition, the first light emitting device 207B A protective layer 2 is provided to protect the first to fourth light emitting devices 207W from harmful substances or environments. The protective layer 204 may be formed of an oxide, a nitride, a fluoride, a sulfide, or Ternary compounds, metals or polymers can be used, for example, aluminum oxide, acid Hafnium oxide, hafnium silicate, lanthanum oxide, silicon oxide, strontium titanate tantalum oxide, titanium oxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, Yttrium oxide, cerium oxide, scandium oxide, erbium oxide, vanadium oxide Or materials containing indium oxide, aluminum nitride, hafnium nitride, silicon nitride, Tantalum nitride, titanium nitride, niobium nitride, molybdenum nitride, zirconium nitride or nitride Materials containing gallium, etc., nitrides containing titanium and aluminum, titanium and aluminum oxides containing aluminum, oxides containing aluminum and zinc, oxides containing manganese and zinc carbides containing cerium and strontium, sulfides containing erbium and aluminum Materials containing oxides of yttrium and zirconium, etc., can be used. Cut.

[0070] In addition, by bonding the color conversion layer and the light emitting device with a resin having an appropriate refractive index, As a result, more of the light emitted from the color conversion layer can reach the color conversion layer. Since the light is intensified, a highly efficient light-emitting device can be manufactured. It may also serve as the protective layer 204, or may be provided between the protective layer 204 and the color conversion layer. The refractive index of the resin is preferably 1.4 to 2.0, and more preferably 1.7. It is more preferable that the refractive index of the layer having a high refractive index is between the transparent electrode and the color conversion layer. The presence of the thin-film mode reduces the loss of light, making it possible to obtain a more efficient light-emitting device. can.

[0071] In addition, since the first pixel 208B emits light that does not pass through a color conversion layer, the first pixel 208B emits the most primary color of light. It is preferable that the pixel emits blue light, which has high energy. In the case where the first light-emitting device 207B to the fourth light-emitting device 207W emit light of the same color, In this case, it is preferable that the light-emitting device emits blue light. It is advantageous in terms of cost to use the same material, but different luminescent center materials may be used. stomach.

[0072] In addition, if a different light-emitting device is not created for each pixel color, the light-emitting device The emission of the luminescent center substance is blue light (the peak wavelength of the emission spectrum is 440 nm to 5 20 nm, preferably about 420 nm to 480 nm). The peak wavelength of the emission spectrum of a substance is calculated from the PL spectrum in the solution state. The relative dielectric constant of the organic compound that constitutes the EL layer of the device is about 3, so the light emission of the light-emitting device The ratio of the solvent to put the luminescence center substance into solution in order to avoid discrepancies with the spectrum The dielectric constant at room temperature is preferably 1 or more and 10 or less, and more preferably 2 or more and 5 or less. Specifically, hexane, benzene, toluene, diethyl ether, ethyl acetate, Examples of solvents include chloroform, chlorobenzene, and dichloromethane. A general-purpose solvent having a relative dielectric constant of 2 to 5 and high solubility is more preferable. For example, toluol is Preferably, the solvent is benzene or chloroform.

[0073] The color conversion layer 205G contains a material that absorbs light from the second light emitting device 207G and emits light. The light emitted from the second light-emitting device 207G is incident on the color conversion layer 205G and is converted into a long-wavelength light. Green light (with a peak wavelength of 500 nm to 600 nm, preferably 50 The 205R also has a color conversion layer, and the light emitted is converted to a color The transfer layer 205R contains a material that absorbs light from the third light-emitting device 207R and emits light. The light emitted from the third light-emitting device 207R is incident on the color conversion layer 205R and converted into a light having a wavelength of Long red light (emission spectrum peak wavelength is 600 nm to 750 nm, preferably 6 The color conversion layer 205G and the color conversion layer 205R is designed to fully absorb light from light-emitting devices and transmit as little light as possible. It is preferable that the color-changing substance, such as QD, is contained at a certain concentration.

[0074] Similarly, 205W is a color conversion layer, and the color conversion layer 205W includes a fourth light emitting device 207W. The fourth light-emitting device 207W includes a substance that absorbs light from the fourth light-emitting device 207W and emits light. is incident on the color conversion layer 205W and emits yellow light with a long wavelength (the peak wavelength of the emission spectrum is 5 60nm to 610nm, preferably 580nm to 595nm) and emitted. Color conversion layer 205W contains rare earth elements such as europium, cerium, and yttrium. It contains at least one or more elements and can efficiently convert blue light into yellow light. The color conversion layer 205W performs color conversion to an extent that the light from the light emitting device is appropriately transmitted. The light converted by the color conversion layer 205W and the light transmitted through the color conversion layer 205W are The light from the light-emitting devices is mixed to produce white light.

[0075] Each of these pixels may further include a color filter.

[0076] In a light-emitting device having such a configuration, the light reaching the color conversion layer is absorbed by the electrodes, etc. The optical loss due to the absorption, the optical loss due to the evanescent mode, and the The amount achieved is the amount excluding the optical loss due to the optical confinement caused by the refractive index difference between the liquid and the light-emitting device. For this reason, there is a need to reduce these losses.

[0077] Therefore, the light-emitting device 207 is a light-emitting device having a configuration as shown in FIGS. A light-emitting device used in a light-emitting device according to one embodiment of the present invention will be described below. .

[0078] The light-emitting device shown in FIG. 2A includes a first electrode 101, a second electrode 102, and an EL layer 1. 03, the EL layer includes at least a layer made of a material having a small refractive index, The blue emission (peak wavelength of the emission spectrum is from 440 nm to 52 nm) exhibited by the luminescent center substance 0 nm, preferably about 420 nm to 480 nm), for example, a wavelength of 467 nm The layer includes a material having a refractive index of 1.75 or less for light.

[0079] The EL layer 103 has a light-emitting layer 113, a hole-injection layer 111 and / or a hole-transport In addition to the layer 112, the electron transport layer 114 and / or the electron injection layer 115, various functional layers may be included. The light-emitting layer 113 may include a light-emitting material, and the light-emitting device 207 may include the light-emitting material. Light is emitted from the light-emitting material. The light-emitting layer 113 contains a host material and other materials. The layer made of a material having a refractive index of 1.75 or less for light with a wavelength of 467 nm may be Any layer other than the light emitting layer 113 may be used, but the hole injection layer 111, the hole transport layer 112, and and / or the electron transport layer 114. The presence of these in the EL layer causes light to be lost as optical losses within the device. Therefore, the evanescent mode and thin film mode are suppressed, and the light extraction efficiency is improved. In this case, a light-emitting device having a good external quantum efficiency can be obtained. It is preferable that the light emitting layer is provided on the side of the electrode from which light is emitted.

[0080] Next, examples of the detailed structure and materials of the above-mentioned light-emitting device will be described. As described above, the light emitting device has a pair of electrodes, a first electrode 101 and a second electrode 102, between which a light emitting diode (LED) is formed. The EL layer 103 is made up of a plurality of layers, and in any part of the EL layer 103, A layer having a refractive index of 1.75 or less, preferably 1.65 or less, for light having a wavelength of 67 nm; The material has a refractive index of 1.75 or less, preferably 1.65 or less, for light with a wavelength of 467 nm. The low refractive index reduces optical loss and improves light extraction efficiency of light-emitting devices. In order to improve the efficiency, the refractive index is preferably 1.74 or less, and more preferably 1.73 or less. , more preferably 1.72 or less, more preferably 1.71 or less, more preferably 1.70 or less, more preferably 1.69 or less, more preferably 1.68 or less, more preferably 1. 67 or less, more preferably 1.66 or less, and more preferably 1.65 or less. The refractive index is the ordinary refractive index or the average refractive index of the ordinary refractive index and the extraordinary refractive index.

[0081] The first electrode 101 is made of a metal, an alloy, or a conductive material having a large work function (specifically, 4.0 eV or more). It is preferable to form the film using a compound such as a carboxylic acid or a mixture thereof. For example, indium tin oxide (ITO), silicon Indium oxide-tin oxide and indium oxide-zinc oxide containing silicon oxide or silicon oxide , indium oxide containing tungsten oxide and zinc oxide (IWZO), etc. These conductive metal oxide films are usually formed by sputtering, but they can also be formed by sol-gel deposition. An example of the method for producing the indium oxide-oxide film is the indium oxide-oxide film. Zinc was sintered using a target containing 1 to 20 wt% zinc oxide in indium oxide. Also, tungsten oxide and zinc oxide are used. Indium oxide (IWZO) contains 0.5% tungsten oxide relative to indium oxide. Sputtering was performed using a target containing 5-5wt% of ZnO and 0.1-1wt% of Zinc Oxide. It can also be formed by the method. In addition, gold (Au), platinum (Pt), nickel (Ni) , Tungsten (W), Chromium (Cr), Molybdenum (Mo), Iron (Fe), Cobalt ( Co), copper (Cu), palladium (Pd), or nitrides of metallic materials (e.g., titanium nitride Graphene can also be used. By using this in the layer 103 that is in contact with the first electrode 101, the electric field can be reduced regardless of the work function. You will be able to choose the pole material.

[0082] The EL layer 103 preferably has a laminated structure, but there is no particular limitation on the laminated structure. As described above, the hole injection layer, the hole transport layer, the electron transport layer, the electron injection layer, the carrier Various layer structures can be applied, such as blocking layers, exciton blocking layers, charge generating layers, etc. In this embodiment, as shown in FIG. 2(A), a hole injection layer 111, a hole transport layer 112, In addition to the light-emitting layer 113, the structure includes an electron transport layer 114 and an electron injection layer 115. As shown in FIG. 1B, in addition to the hole injection layer 111, the hole transport layer 112, and the light emitting layer 113, The electron transport layer 114, the electron injection layer 115, and the charge generation layer 116 are arranged in two different configurations. The materials constituting each layer are specifically shown below.

[0083] The hole injection layer 111 is a layer containing a substance having an acceptor property. The substance may be either an organic compound or an inorganic compound.

[0084] Acceptor substances include compounds with electron-withdrawing groups (halogen groups and cyano groups). The compound can be used, such as 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroethylene. Quinoline dimethan (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11- Hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT- CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane ( Abbreviation: F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9 , 10-octafluoro-7H-pyren-2-ylidene)malononitrile, etc. In particular, the electron-withdrawing group is attached to the condensed aromatic ring having multiple heteroatoms, such as HAT-CN. The bonded compound is preferably thermally stable. Also, the electron-withdrawing group (especially the fluoro group) Radialene derivatives that have halogen or cyano groups such as Specifically, α,α',α''-1,2,3-cyclopropane triisocyanate is preferred. Lidentris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile] α,α',α''-1,2,3-cyclopropanetriylidenetris[2,6-dichloro b-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α, α',α''-1,2,3-Cyclopropanetriylidenetris[2,3,4,5,6- Pentafluorobenzeneacetonitrile, etc. In addition to the organic compounds mentioned above, molybdenum oxide, vanadium oxide, ruthenium oxide, etc. Inorganic compounds such as tungsten oxide, manganese oxide, etc. can also be used. In addition, there are other phthalocyanine compounds such as phthalocyanine (abbreviation: H2Pc) and copper phthalocyanine (CuPc). Phthalocyanine complex compounds, 4,4'-bis[N-(4-diphenylaminophenyl) -N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis( 3-Methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl aromatic amine compounds such as diamine (DNTPD) or polyamines (3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / The hole injection layer 111 can also be formed from a polymer compound such as polysilicon (PSS). A substance with septal properties is a material that is resistant to the application of an electric field from the adjacent hole transport layer (or hole transport material). Addition of electrons can remove them.

[0085] In addition, the hole injection layer 111 may be formed by adding the above-mentioned acceptor substance to a material having a hole transporting property. A composite material in which a material having hole transport properties and an acceptor property are mixed can also be used. By using a composite material containing a metal, it is possible to select a material for forming an electrode regardless of its work function. In other words, not only a material with a large work function but also a material with a specific This makes it possible to use materials with small thermal conductivity functions.

[0086] Examples of materials having hole transport properties that can be used in the composite material include aromatic amine compounds and carbazole. Derivatives, aromatic hydrocarbons, polymer compounds (oligomers, dendrimers, polymers, etc.) Various organic compounds having hole transport properties can be used for the composite material. The materials are 1×10 -6 cm 2 It is preferable that the material has a hole mobility of 1 / Vs or more. In the following, a material having a hole transport property in a composite material will be described. Specific examples of organic compounds are listed below.

[0087] Aromatic amine compounds that can be used in composite materials include N,N'-di(p-tolyl) )-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4' -Bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation Name: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl }-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: D NTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenyl Carbazole derivatives Specifically, 3-[N-(9-phenylcarbazol-3-yl)-N-phenyl nylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N -(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazol PCzPCA2 (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenyl Carbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1 ), 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tri 4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-10 -phenylanthracen-9-yl)phenyl]-9H-carbazole (abbreviation: CzPA ), 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenyl Examples of aromatic hydrocarbons that can be used include 2-tert-butylbenzene. -Butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2- tert-Butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3, 5-Diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9 ,10-Bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,1 0-Di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene 2-tert-butylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAn th), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA) , 2-tert-butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7- Tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl 9,10-di(2-naphthyl)anthracene, 9,9'-bianthryl, 10,1 0'-Diphenyl-9,9'-bianthryl, 10,10'-bis(2-phenylphenyl) 10,10'-bis[(2,3,4,5,6-pentafluorophenyl) phenyl)phenyl]-9,9'-bianthryl, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, etc. In addition, pentacene, coronene, etc. can also be used. Examples of aromatic hydrocarbons having a vinyl group include 4,4'-bis(2,2 -diphenylvinyl)biphenyl (abbreviation: DPVBi), 9,10-bis[4-(2,2 -diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA), etc. The organic compound of one embodiment of the present invention can also be used.

[0088] In addition, poly(N-vinylcarbazole) (abbreviation: PVK) and poly(4-vinyltriphenyl Poly[N-(4-{N'-[4-(4-diphenylamine) N'-phenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide Name: PTPDMA), poly[N,N'-bis(4-butylphenyl)-N,N'-bis( It is also possible to use polymer compounds such as poly(phenyl)benzidine (abbreviation: Poly-TPD). Cut.

[0089] The hole transporting materials used in the composite material include carbazole skeleton, dibenzofuran skeleton, It has either an orchid skeleton, a dibenzothiophene skeleton, or an anthracene skeleton. More preferred are those having a substituent containing a dibenzofuran ring or a dibenzothiophene ring. aromatic monoamines having a naphthalene ring, or 9-fluorenyl groups may also be an aromatic monoamine bonded to the nitrogen atom of the amine via an arylene group. In addition, the second organic compound has an N,N-bis(4-biphenyl)amino group. If the material has a high quality, it is possible to manufacture a light-emitting device having a long life. Specific examples of such second organic compounds include N-(4-biphenyl)-6,N-diphenyl. Nylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), ,N-Bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan -8-Amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphthyl) Tri[1,2-d]furan-8-yl-4''-phenyltriphenylamine (abbreviation: Bn fBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]f Ran-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzene Zo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)), N, N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation Name: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl) phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-( Dibenzothiophene-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation Name: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenyl Amine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4'' -Diphenyltriphenylamine (abbreviation: BBAβNBi), 4-(2;1'-binaphthalene 4',4''-diphenyltriphenylamine (abbreviation: BBAαNβN B) 4,4'-diphenyl-4''-(7;1'-binaphthyl-2-yl)triphenyl BBAαNβNB-03, 4,4'-diphenyl-4''-(7-phenyl) phenyl)naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4- (6;2'-binaphthyl-2-yl)-4',4''-diphenyltriphenylamine ( Abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl -2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4-(1;2' -Binaphthyl-4-yl)-4',4''-diphenyltriphenylamine (abbreviation: BB AβNαNB), 4-(1;2'-binaphthyl-5-yl)-4',4''-diphenyl Triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4 '-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB ), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-furan mTPBiAβNBi, 4-(4-biphenylyl) -4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation Name: TPBiAβNBi), 4-(1-naphthyl)-4'-phenyltriphenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation :αNBB1BP), 4,4'-diphenyl-4''-[4'-(carbazole-9-yl) yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[ 4-(3-phenyl-9H-carbazol-9-yl)phenyl]tris(1,1'-biphenyl) Phenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carba

[0046] -4'-(2-naphthyl)-4''-phenyl YGTBiβNB, N-[4-(9-phenyl-9H- Carbazol-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9 '-Spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-Bi S([1,1'-biphenyl]-4-yl)-9,9'-spirobi[9H-fluorene] -2-amine (abbreviation: BBASF), N,N-bis([1,1'-biphenyl]-4-isopropyl)amine 9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: BBASF(4) ), N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoro) 9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: oF BiSF), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluorene-2 -yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl )phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1- Naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-(9-phenyl Fluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3' -(9-Phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP) , 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triflate phenylamine (abbreviation: BPAFLBi), 4-phenyl-4'-(9-phenyl-9H- Carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-di Phenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine PCBBi1BP, 4-(1-naphthyl)-4'-(9-phenyl-9H- Carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di( 1-Naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenyl PCBNBB, N-phenyl-N-[4-(9-phenyl-9H- 9,9'-bifluoren-2-amine (abbreviation : PCBASF), N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-N- [4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluorene -2-amine (abbreviation: PCBBiF), N,N-bis(9,9-dimethyl-9H-fluoro 9,9'-spirobi-9H-fluoren-4-amine, N,N-bis (9,9-Dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluor Oren-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl) -9,9'-Spirobi-9H-fluorene-2-amine, N,N-bis(9,9-dimethyl (9,9'-spirobi-9H-fluoren-1-amino)- Examples of such compounds include

[0090] In addition, the HOMO level of the hole-transporting material used in the composite material is -5.7 eV. It is more preferable that the material has a relatively deep HOMO level of not less than -5.4 eV. The material having hole transport properties used in the composite material has a relatively deep HOMO level. This facilitates the injection of holes into the hole transport layer 112, and also provides a light-emitting device with a long life. This makes it easier to obtain a vice.

[0091] In addition, the above composite material may further contain an alkali metal fluoride, an alkaline earth metal fluoride, or and alkyl fluoride (preferably fluorine atoms in the layer) By using a fluorine-containing compound having a ratio of 20% or more, the refractive index of the layer can be reduced. Also by this method, a layer having a low refractive index can be formed inside the EL layer 103, and the light-emitting device The external quantum efficiency can be improved. As the amount of fluoride increases, the spin density decreases, so the composite material The spin density at this time is 1.0×10 18 spins / cm 3 More preferably, it is equal to or greater than this. In addition, when fluoride is mixed into the hole injection layer, the acceptor material is an inorganic compound, especially It is preferable to use molybdenum oxide for the above-mentioned.

[0092] As a material having hole transport properties, 1,1-bis-(4-bis(4-methyl-phenyl) A compound with a small refractive index such as 1,2-diphenyl-2,4-diamino-phenyl-cyclohexane (abbreviation: TAPC) The refractive index of the hole injection layer 111 can also be reduced by using an organic compound. .

[0093] By forming the hole injection layer 111, the hole injection property is improved, and the driving voltage is small. In addition, organic compounds with acceptor properties can be easily evaporated. It is an easy-to-use material because it is easy to form a film.

[0094] The hole transport layer 112 is formed by including a material having a hole transport property. The materials are 1×10 -6 cm 2 It is preferable that the hole mobility is equal to or higher than / Vs. .

[0095] As the material having the hole transport property, 4,4'-bis[N-(1-naphthyl)-N-phenyl] N,N'-bis(3-methylphenyl)- N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD ), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenyl 4-phenyl-4'-(9-phenylfluoro)biphenyl (abbreviation: BSPB), 4-phenyl-3'-(phenyl-9-yl)triphenylamine (abbreviation: BPAFLP), 9-Phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4 -Phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine PCBA1BP, 4,4'-diphenyl-4''-(9-phenyl-9H- Carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1- naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine PCBANB, 4,4'-di(1-naphthyl)-4''-(9-phenyl- 9H-Carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9- Dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl) phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-( 9-Phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluor Compounds with aromatic amine skeletons such as PCBASF (abbreviation: PCBASF) and 1 ,3-Bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-di(N-carbazolyl)benzene 3,6-bis(3,5-diphenylphenyl)- 9-Phenylcarbazole (abbreviation: CzTP), 3,3'-bis(9-phenyl-9H- Carbazole (PCCP) and other compounds with a carbazole skeleton, such as 4,4' ,4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: D BT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluorene -9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4 -(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothia Compounds with a thiophene skeleton, such as DBTFLP-IV, and 4,4 ',4''-(Benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DB F3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl furan skeleton such as mmDBFFLBi-II Among the above, compounds having an aromatic amine skeleton and Compounds having a benzol skeleton have good reliability, high hole transport properties, and high driving current. In addition, the hole injection layer 111 is preferably made of a composite material. The materials having the transport property can also be suitably used as the material for forming the hole transport layer 112. There can be.

[0096] The light-emitting layer 113 contains a light-emitting substance and a host material. The material may contain both materials at the same time. Also, the material may be a laminate of two layers with different compositions.

[0097] The luminescent material may be a fluorescent material, a phosphorescent material, or a thermally activated delayed fluorescence (T The material may be a material that exhibits the ADF or other luminescent material. In one embodiment, the light-emitting layer 113 is a layer that exhibits fluorescent emission, in particular, a layer that exhibits blue fluorescent emission. This can be suitably applied depending on the circumstances.

[0098] In the light-emitting layer 113, examples of materials that can be used as the fluorescent material include the following: Examples include the following: Other fluorescent materials can also be used.

[0099] 5,6-Bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine PAP2BPy, 5,6-bis[4'-(10-phenyl-9-anthracene N, N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl] )phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-biphenyl Bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluorene 9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn ), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-di Phenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazo 4'-(10-phenyl-9-yl)-triphenylamine (abbreviation Name: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl N,9-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), Nyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole -3-amine (abbreviation: PCAPA), Perylene, 2,5,8,11-tetra-tert- Butylperylene (TBP), 4-(10-phenyl-9-anthryl)-4'-( 9-Phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAP) A) N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1 -phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine]( Abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2- anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-t N,N,N',N-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA) ',N'',N'',N''',N'''-Octaphenyldibenzo[g,p]chrysene -2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N-(9,1 0-Diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-a 2PCAPA, N-[9,10-bis(1,1'-biphenyl-2-yl)] )-2-Anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N' -Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10 -Bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-tri Phenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis( 1,1'-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl N,N,nyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), 9-Triphenylanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 545 T, N,N'-Diphenylquinacridone (abbreviation: DPQd), Rubrene, 5,12-bis (1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT ), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4 H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl -6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizine -9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: D CM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,1 1-Diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'- Tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10 -diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1 ,7,7-Tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij] Quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethylphenyl) tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizine 9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DC JTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}- 4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2, 6-Bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetramethyl 4H-pyrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl {N,N'-diphenyl-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphtho] [1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), 3,1 0-Bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamino] ]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nb f(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenyl 3,10Fr A2Nbf(IV)-02) are particularly notable. Instead of pyrene diamine compounds such as MemFLPAPrn and 1,6BnfAPrn-03, The condensed aromatic diamine compound represented by the formula (I) has a high hole trapping property and is excellent in luminous efficiency and reliability. This is preferable because

[0100] In the case where a phosphorescent material is used as the light-emitting material in the light-emitting layer 113, it is possible to use Examples of such materials include the following:

[0101] Tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H -1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III ) (abbreviation: [Ir(mpptz-dmp)3]), tris(5-methyl-3,4-diphenyl Nyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mpt z)3]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H -1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrtz-3 b) Organometallic iridium complexes having a 4H-triazole skeleton, such as tris [3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-trimethyl [Ir(Mptz1-mp)3], tris(1 -Methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium (III) (abbreviation: [Ir(Prptz1-Me)3]) Organometallic iridium complexes with fac-tris[(1-2,6-diisopropyl phenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir (iPrpmi)3]), tris[3-(2,6-dimethylphenyl)-7-methylimide Dazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmp and organometallic iridium complexes having an imidazole skeleton, such as impt-Me3). Bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium( III) Tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4' ,6'-Difluorophenyl)pyridinato-N,C 2’ ]Iridium(III) picolina Fluorocarbon (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)fluorene} Phenyl]pyridinato-N,C 2’}Iridium(III) picolinate (abbreviation: [Ir( CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyri Ginat-N,C 2’ ]Iridium(III) acetylacetonate (abbreviation: FIraca c) Organometallic iridates having phenylpyridine derivatives as ligands having electron-withdrawing groups such as These are compounds that exhibit blue phosphorescence, with wavelengths ranging from 440 nm to It is a compound that has an emission peak at 520 nm.

[0102] In addition, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), tris(4-t-butyl-6-phenylpyrimidinato)yl Ir(tBuppm)3, diacetylacetonate (6-Methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mp pm)2(acac)]), (acetylacetonato)bis(6-tert-butyl-4- Phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm)2(ac ac)]), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpiperidinyl [Ir(nbppm)2(acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenyl [Pyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm)2(acac)] ), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(II I) (abbreviation: [Ir(dppm)2(acac)]) Metal-iridium complexes and (acetylacetonato)bis(3,5-dimethyl-2-phenyl Rupyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac) ]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyridine Dinato)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]) Organometallic iridium complexes with pyrazine skeletons such as tris(2-phenylpyridinium) Nat-N,C 2’ ) Iridium(III) (abbreviation: [Ir(ppy)3]), bis(2- Phenylpyridinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), bis(benzo[h]quinolinato)iridium (I II) Acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), tris(beta Tris[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq)3]) (2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(pq) 3]), bis(2-phenylquinolinato-N,C 2’ ) Iridium(III) acetylated A compound with a pyridine skeleton, such as setonate (abbreviation: [Ir(pq)2(acac)]) In addition to the organometallic iridium complexes, tris(acetylacetonato)(monophenanthroline)tetraacetate Rare earth metals such as rubium(III) (abbreviation: [Tb(acac)3(Phen)]) These are mainly compounds that exhibit green phosphorescence and have wavelengths between 500 nm and 6 The emission peak is at 100 nm. The body is particularly preferred because it is remarkably excellent in reliability and luminous efficiency.

[0103] Also, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinyl] Nat[Iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis [4,6-Bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)irid Ir(III) (abbreviation: [Ir(5mdppm)2(dpm)]), bis[4,6-di( Naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]) iridium complexes of the genus acetylacetonato, bis(2,3,5-triphenylpyrazine) Iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2, 3,5-Triphenylpyrazinato)(dipivaloylmethanato)iridium(III)(abbreviation Name: [Ir(tppr)2(dpm)]), (acetylacetonato)bis[2,3-bis (4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fd pq)2(acac)]) and other organometallic iridium complexes with pyrazine skeletons. Tris(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir (piq)3]), bis(1-phenylisoquinolinato-N,C 2’ ) Iridium (II I) Pyridyl acetylacetonate (abbreviation: [Ir(piq)2(acac)]) In addition to organometallic iridium complexes with iridium skeletons, 2,3,7,8,12,13,17,18 -Octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP) Platinum complexes such as tris(1,3-diphenyl-1,3-propanedionato)(monophenyl Anthroline) europium(III) (abbreviation: [Eu(DBM)3(Phen)]), Tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthate Europium(III) (abbreviation: [Eu(TTA)3(Phen)]) These are compounds that exhibit red phosphorescence and have a wavelength of 60 The emission peak is between 0 nm and 700 nm. The rhodium complex can emit red light with good chromaticity.

[0104] In addition to the phosphorescent compounds described above, known phosphorescent light-emitting substances may be selected and used. stomach.

[0105] TADF materials include fullerene and its derivatives, acridine and its derivatives, and eosin. Derivatives of magnesium (Mg), zinc (Zn), cadmium (Cd) and other metals can also be used. (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (P d) and the like. The metal-containing porphyrin includes, for example, For example, the protoporphyrin-tin fluoride complex (SnF2(Pro to IX), mesoporphyrin-tin fluoride complex (SnF2(Meso IX)), Hematoporphyrin-Tin Fluoride Complex (SnF2(Hemato IX)), Copropor Phyllin tetramethyl ester-tin fluoride complex (SnF2(Copro III-4M e)), octaethylporphyrin-tin fluoride complex (SnF2(OEP)), etiopo Luphirin-Tin Fluoride Complex (SnF2(Etio I)), Octaethylporphyrin -platinum chloride complex (PtCl2OEP) and the like.

[0106] [ka]

[0107] In addition, 2-(biphenyl-4-yl)-4,6-bis(12-phenyl)-2-phenylpropanediol having the following structural formula is also available. phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine ( Abbreviation: PIC-TRZ) and 9-(4,6-diphenyl-1,3,5-triazine-2- yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCzT zn), 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl PCCzPT zn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl 3-[4-(5-phenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), -5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1, 2,4-Triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-azide Clydin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[ 4-(9,9-Dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9 π-electron-rich heteroaromatic rings such as '-anthracene]-10'-one (abbreviation: ACRSA) and a heterocyclic compound having either or both of a π-electron deficient heteroaromatic ring can also be used. Since the heterocyclic compound has a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, Among them, those having a π-electron-deficient heteroaromatic ring are preferred because they have high electron transport properties and hole transport properties. Among the skeletons that have pyridine skeleton, diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyri The benzene skeleton) and the triazine skeleton are preferred because they are stable and reliable. Benzofuropyrimidine skeleton, benzothienopyrimidine skeleton, benzofuropyrazine skeleton, The zothienopyrazine skeleton is preferred because it has high acceptor properties and good reliability. Among the skeletons having electron-rich heteroaromatic rings, the acridine skeleton, the phenoxazine skeleton, and the fluorocarbon skeleton are The ethene skeleton, the furan skeleton, the thiophene skeleton, and the pyrrole skeleton are stable and reliable. It is preferable that the compound has at least one of the furan skeletons. The dibenzofuran skeleton is used for the thiophene skeleton, and the dibenzothiophene skeleton is used for the thiophene skeleton. The pyrrole skeleton is preferably an indole skeleton, a carbazole skeleton, an indole skeleton, Carbazole skeleton, bicarbazole skeleton, 3-(9-phenyl-9H-carbazole-3 In addition, a π-electron-rich heteroaromatic ring and a π-aryl group are particularly preferred. In the case of a substance in which an electron-deficient heteroaromatic ring is directly bonded, the electron-donating property of the π-electron-rich heteroaromatic ring is utilized. The electron-accepting properties of the π-electron-deficient heteroaromatic rings are both strong, and the energies of the S1 and T1 levels are This is particularly preferred because the difference is small and thermally activated delayed fluorescence can be obtained efficiently. Instead of a π-electron deficient heteroaromatic ring, an aromatic ring with an electron-withdrawing group such as a cyano group is used. In addition, as the π-electron-rich skeleton, an aromatic amine skeleton, a phenazine skeleton, etc. may be used. In addition, a xanthene skeleton, a thioxanthene skeleton, etc., can be used as a π-electron deficient skeleton. Dioxide skeleton, oxadiazole skeleton, triazole skeleton, imidazole skeleton, an The boron-containing skeletons such as phenylborane and boranthrene, benzonitrile, The aromatic ring or heteroaromatic ring having a nitrile group or a cyano group, such as cyanobenzene, Carbonyl skeletons such as phenones, phosphine oxide skeletons, sulfone skeletons, etc. can be used. In this way, at least one of a π-electron deficient heteroaromatic ring and a π-electron rich heteroaromatic ring can be used. In place of one another, π-electron deficient and π-electron rich backbones can be used.

[0108] [ka]

[0109] In addition, TADF materials have a small difference between the S1 and T1 levels, and can be triple-phased by reverse intersystem crossing. The function of converting energy from first excitation energy to singlet excitation energy Therefore, the triplet excitation energy can be converted to a single state by a small amount of thermal energy. It is possible to upconvert to singlet excited energy (reverse intersystem crossing), and efficiently convert singlet excited states It is possible to generate triplet excitation energy and convert it into luminescence. .

[0110] In addition, exciplexes (complexes) that form excited states with two types of substances The difference between the S1 and T1 levels is extremely small. As a TADF material capable of converting triplet excitation energy into singlet excitation energy, It has all the functions.

[0111] As an index of the T1 level, the phosphorescence spectrum observed at low temperatures (e.g., from 77 K to 10 K) As for the TADF material, Draw a tangent line to the S1 level, and the energy of the wavelength of the extrapolated line is the S1 level of the phosphorescence spectrum. When a tangent line is drawn at the long side of the tail and the energy of the wavelength of the extrapolated line is taken as the T1 level, The difference between S1 and T1 is preferably 0.3 eV or less, and more preferably 0.2 eV or less. Even more preferred.

[0112] In addition, when a TADF material is used as a light-emitting material, the S1 level of the host material is The T1 level of the host material is preferably higher than the S1 level of the TADF material. It is preferable that the concentration is higher than the above level.

[0113] The host material of the light-emitting layer may be a material having an electron transporting property or a material having a hole transporting property. Various carrier transport materials can be used, such as TADF materials.

[0114] Materials with hole transport properties include those having an amine skeleton or a π-electron-rich heteroaromatic skeleton. Organic compounds are preferred. For example, 4,4'-bis[N-(1-naphthyl)-N-phenylalanine] N,N'-bis(3-methylphenyl)-N,N' -Diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4, 4'-Bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino] ]biphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluorene-9 -yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenyl mBPAFLP, 4-phenyl 4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation : PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazo PCBBi1BP), 4-(1-naphthyl-3-yl)triphenylamine )-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation : PCBAN B), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazone) PCBNBB, 9,9-dimethyl -N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl ]fluorene-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl Nyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluorene-2 -amine (abbreviation: PCBASF), and compounds with aromatic amine skeletons such as 1,3-biphenyl mCP, 4,4'-di(N-carbazolyl)benzene Biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenyl Nylcarbazole (abbreviation: CzTP), 3,3'-bis(9-phenyl-9H-carbazo Compounds with a carbazole skeleton, such as PCCP (abbreviation: PCCP), and 4,4',4'' -(Benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P -II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluorene-9-yl] 4-[4-(9-phenyl)dibenzothiophene (abbreviation: DBTFLP-III) Phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) and other compounds with thiophene skeletons, such as 4,4',4' '-(Benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P- II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]fluor phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II) Among the above, compounds having an aromatic amine skeleton and carbazole Compounds having such a structure have good reliability and high hole transport properties, and are therefore useful for reducing the driving voltage. In addition, the organic compounds listed as examples of the first substance may also be used. This can be done.

[0115] As an example of a material having electron transport properties, bis(10-hydroxybenzo[h]quinoli Nat)beryllium(II)(abbreviation:BeBq2), bis(2-methyl-8-quinolinolato )(4-phenylphenolato)aluminum(III)(abbreviation: BAlq), bis(8- Quinolinolato)zinc(II)(abbreviation:Znq), bis[2-(2-benzoxazolyl) phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl) Metal complexes such as phenolatozinc(II) (abbreviation: ZnBTZ) and π-electron-deficient heteroaromatic complexes Organic compounds having an aromatic ring skeleton are preferred. Organic compounds having a π-electron deficient heteroaromatic ring skeleton Examples of the compounds include 2-(4-biphenylyl)-5-(4-tert-butylphenyl) )-1,3,4-Oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4- Phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxa 9-[4-(5-phenyl-1-azolyl]benzene (abbreviation: OXD-7), ,3,4-Oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO 11), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl- 1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophene-4 -yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm Heterocyclic compounds with polyazole skeletons such as 2-[3-(dibenzothiophene-2-yl)-II] and 2m-phenyl-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDB q-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]di Benzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-( 9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxalate 2mCzBPDBq, 4,6-bis[3-(phenanthren-9-yl)phenyl]phenyl phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-diphenyl Diazothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II) Heterocyclic compounds with an aryl skeleton and 3,5-bis[3-(9H-carbazol-9-yl] )phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3-(3-pyridyl Heterocyclization of pyridine skeletons such as TmPyPB Among the above, heterocyclic compounds having a diazine skeleton and heterocyclic compounds having a pyridine skeleton are preferred. Heterocyclic compounds having the formula (I) are preferred because of their excellent reliability. Heterocyclic compounds with a pyrazine skeleton have high electron transport properties and contribute to reducing the driving voltage. .

[0116] The TADF materials that can be used as host materials are listed above as TADF materials. When a TADF material is used as a host material, the TA The triplet excitation energy generated in the DF material is converted to singlet excitation energy by reverse intersystem crossing. This energy is then transferred to the light-emitting material, thereby improving the luminous efficiency of the light-emitting device. In this case, the TADF material acts as an energy donor and the light-emitting material acts as an energy acceptor.

[0117] This is particularly effective when the luminescent material is a fluorescent luminescent material. To obtain high luminous efficiency, the S1 level of the TADF material should be higher than the S1 level of the fluorescent material. In addition, the T1 level of the TADF material is preferably higher than the S1 level of the fluorescent material. Therefore, the T1 level of the TADF material is preferably higher than the T1 level of the fluorescent material. Higher is preferred.

[0118] In addition, the fluorescent substance emits light at a wavelength that overlaps with the lowest energy absorption band of the fluorescent substance. It is preferable to use a TADF material that emits fluorescent light. This is preferable because it allows smooth transfer of excitation energy to the substance and efficiently produces light. stomach.

[0119] In addition, singlet excitation energy is efficiently generated from triplet excitation energy by reverse intersystem crossing. In order for this to happen, it is preferable for carrier recombination to occur in the TADF material. The triplet excitation energy generated in the DF material is transferred to the triplet excitation energy of the fluorescent material. For this purpose, it is preferable that the fluorescent substance has a luminophore ( It is preferable that the compound has a protecting group around the skeleton that causes light emission. A substituent having no carbon atom is preferable, and a saturated hydrocarbon is preferable. Specifically, the substituent has 3 to 10 carbon atoms. The alkyl groups listed below, substituted or unsubstituted cycloalkyl groups with 3 to 10 carbon atoms, A trialkylsilyl group having a number of 3 to 10 is preferred, and a group having a plurality of protecting groups is more preferred. Substituents without π bonds have poor carrier transport function, and therefore have poor carrier transport and The distance between the TADF material and the luminophores of the fluorescent material can be reduced without affecting carrier recombination. Here, the luminophore is the molecule that causes the emission of light in a fluorescent substance. The luminophore preferably has a skeleton with a π bond and contains an aromatic ring. It is preferable that the aromatic ring has a condensed aromatic ring or a condensed heteroaromatic ring. The heterocyclic aromatic rings include phenanthrene skeletons, stilbene skeletons, acridone skeletons, and pheno In particular, the naphthalene skeleton, the anthracene skeleton, and the like can be used. skeleton, fluorene skeleton, chrysene skeleton, triphenylene skeleton, tetracene skeleton, pyrene skeleton It has a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, and a naphthobisbenzofuran skeleton. Such fluorescent substances are preferred because they have high fluorescence quantum yields.

[0120] When a fluorescent substance is used as the light-emitting substance, the host material is a material having an anthracene skeleton. A material having an anthracene skeleton is preferably used as a host material for a fluorescent material. When used as a host material, it is possible to realize a light-emitting layer having good light-emitting efficiency and durability. The anthracene skeleton used as the material includes a diphenylanthracene skeleton, In particular, a substance having a 9,10-diphenylanthracene skeleton is preferred because it is chemically stable. In addition, when the host material has a carbazole skeleton, the hole injection / transport properties are improved. However, a benzocarbazole skeleton in which a benzene ring is further condensed to a carbazole is preferable. When it contains carbazole, the HOMO becomes shallower by about 0.1 eV than that of carbazole, making it easier for holes to enter. In particular, when the host material contains a dibenzocarbazole skeleton, The HOMO is shallower than that of the sol by about 0.1 eV, making it easier for holes to enter, and the hole transport Therefore, it is more preferable as a host material. Preferred are 9,10-diphenylanthracene and carbazole skeletons (or It is a substance that simultaneously has a benzocarbazole skeleton and a dibenzocarbazole skeleton. From the viewpoint of the hole injection and transport properties, a benzofluorene skeleton was used instead of a carbazole skeleton. Dibenzofluorene and dibenzofluorene skeletons may also be used. Examples of such materials include 9-phenyl 3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole ( Abbreviation: PCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H- Carbazole (abbreviation: PCPN), 9-[4-(10-phenyl-9-anthracenyl) phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl-9 -anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBC zPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[ b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-{ 4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4'-yl}anthra 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]phenyl Nyl]anthracene (abbreviation: αN-βNPAnth), etc. cgDBCzPA, 2mBnfPPA, and PCzPA are preferred because they show very good properties. This is a good choice.

[0121] The host material may be a mixture of a plurality of substances. When used, a material having an electron transporting property and a material having a hole transporting property may be mixed. It is preferable to mix a material having an electron transporting property with a material having a hole transporting property. In this way, the transport properties of the light-emitting layer 113 can be easily adjusted, and the recombination region can be easily controlled. The weight ratio of the content of the material having a hole transporting property to the content of the material having an electron transporting property is The ratio of the material having hole transport properties to the material having electron transport properties may be from 1:19 to 19:1.

[0122] A phosphorescent material can be used as a part of the mixed material. When a fluorescent substance is used as a luminescent substance, the luminescent substance transfers excitation energy to the fluorescent substance. It can be used as an energy donor.

[0123] In addition, these mixed materials may form an exciplex. The luminescence of the exciplex is such that it overlaps with the wavelength of the lowest energy absorption band of the By selecting such a combination, energy transfer becomes smooth and light emission can be obtained efficiently. In addition, the use of this configuration is also preferable because the driving voltage can be reduced.

[0124] At least one of the materials forming the exciplex may be a phosphorescent material. In this way, triplet excitation energy is efficiently converted to singlet excitation energy by reverse intersystem crossing. can be converted to

[0125] As a combination of materials that efficiently form exciplexes, HO It is preferable that the MO level of the material having electron transport properties is equal to or higher than the HOMO level of the material having hole transport properties. When the LUMO level of the material having the electron transport property is higher than the LUMO level of the material having the electron transport property, It is preferable that the LUMO level and the HOMO level of the material are determined by cyclic voltammetry. From the electrochemical properties (reduction potential and oxidation potential) of the material measured by CV measurement It can be derived.

[0126] The formation of an exciplex is based on, for example, the emission spectrum of a material having hole transport properties, the electron transport properties, The emission spectrum of the material having the above structure and the emission spectrum of the mixed film of these materials are shown in Fig. In comparison, the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material ( This can be confirmed by observing the phenomenon of a new peak on the long wavelength side. Alternatively, the transient photoluminescence (PL) of a material with hole transport properties and the electron transport properties The transient PL of the materials with the same properties and the transient PL of the mixed film of these materials were compared. The transient PL lifetime of the film has a longer-lived component than the transient PL lifetime of each material, or has a delayed component. This can be confirmed by observing the difference in the transient response, such as the percentage of In addition, the above-mentioned transient PL may be read as transient electroluminescence (EL). That is, the transient EL of a material with hole transport properties and the transient E of a material with electron transport properties are By comparing the transient EL of the L and the mixed films and observing the difference in the transient response, The formation of the exciplex can be confirmed.

[0127] In one embodiment of the present invention, the light emitted from the light-emitting device is photoluminescent. This results in color conversion. To obtain colors that correspond to the three primary colors of light without creating separate light-emitting devices, The light emitted by the light-emitting device is blue light, which has the highest energy, or blue light, which is also variable. In the case of conversion, the light emitting device preferably emits light in the violet to ultraviolet region.

[0128] The electron transport layer 114 is a layer containing a substance having an electron transport property. The above-mentioned substances having an electron transporting property that can be used as the host material are also usable. can be used.

[0129] The electron transport layer is made of a material having an electron transporting property and an alkali metal or an alkaline earth metal. It is preferable that the electron transport layer 114 contains a simple substance, a compound, or a complex. The electron mobility at a square root of 600 V / cm is 1×10 -7 cm 2 / Vs or more 5×1 0 -5 cm 2 / Vs or less. By lowering the concentration, the amount of electrons injected into the light-emitting layer can be controlled, and the light-emitting layer does not have an excess of electrons. This configuration can prevent the hole injection layer from becoming a composite material. The HOMO level of the material having hole transport properties in the composite material is -5.7 eV or higher. The lifetime is good when the material has a relatively deep HOMO level of 5.4 eV or less. In this case, the material having the electron transporting property is particularly preferable because its HOMO level is −6 The material having the electron transport property is preferably anthracene. It is preferable that the compound is an organic compound having both an anthracene skeleton and a heterocyclic skeleton. It is more preferable that the heterocyclic skeleton is an organic compound containing a nitrogen-containing five-membered ring skeleton. Alternatively, a nitrogen-containing 6-membered ring skeleton is preferred. Examples of such heterocyclic skeletons include a pyrazole ring, an imidazoline ring, and the like. azole ring, oxazole ring, thiazole ring, pyrazine ring, pyrimidine ring, pyridazine ring, etc. How to create a nitrogen-containing five-membered ring skeleton or a nitrogen-containing six-membered ring skeleton that contains two heteroatoms in the ring It is particularly preferable that the alkali metal or alkaline earth metal is an element, a compound or The complex preferably contains an 8-hydroxyquinolinato structure. For example, 8-hydroxyquinolinato-lithium (abbreviation: Liq), 8-hydroxyquinolinato -sodium (abbreviation: Naq) and others. In particular, complexes of monovalent metal ions Among them, a complex of lithium is preferable, and Liq is more preferable. If the compound contains a nolinato structure, its methyl substituents (e.g., 2-methyl and 5-methyl substituents) In addition, an alkali metal or an alkali metal compound may be used in the electron transport layer. The concentration difference (0) of the lithium-earth metals in the thickness direction is It is preferred that the .alpha.-amino acid is present.

[0130] Between the electron transport layer 114 and the second electrode 102, a lithium fluoride layer is formed as an electron injection layer 115. LiF, CsF, Calcium Fluoride (CaF2), 8-Hydroxy-2-(2-methylphenyl)-2-(2-phenylphenyl) Alkali metals or alkaline earth metals such as lithium quinolinate (abbreviation: Liq) The electron injection layer 115 may be a layer containing a metal or a compound thereof. The layer is made of a material containing an alkali metal or an alkaline earth metal or a compound thereof. As the electride, for example, calcium carbonate may be used. Examples include a material in which a high concentration of electrons are added to a mixed oxide of titanium and aluminum.

[0131] Note that the electron-injecting layer 115 is formed using a substance having an electron-transporting property (preferably a substance having a bipyridine skeleton). The above-mentioned alkali metal or alkaline earth metal fluoride is in a microcrystalline state in the organic compound having the above-mentioned structure. It is also possible to use a layer containing a concentration of 50 wt % or more of the refractive index of the layer. Since the layer has a low refractive index, it is possible to provide a light-emitting device with a better external quantum efficiency. It becomes Noh.

[0132] The effect of introducing a low refractive index layer is greater for the layer between the emitting layer and the cathode than for the layer between the anode and the emitting layer. The lower refractive index electron transport layer is larger than the lower refractive index hole injection layer or hole transport layer. However, it is more effective to provide a low refractive index layer on both of them. This improves the device characteristics when color conversion is performed, and a highly efficient color conversion light-emitting device can be obtained. can be done.

[0133] In addition, a charge generating layer 116 may be provided instead of the electron injection layer 115 (FIG. 2(B)). When a potential is applied to the charge generating layer, holes are generated on the layer in contact with the cathode side of the layer, and electrons are generated on the layer in contact with the anode side. The charge generating layer 116 is a layer that can inject electrons into a layer that generates a charge. The P-type layer 117 may also constitute the hole injection layer 111 described above. It is preferable to form the P-type layer 117 using the composite material mentioned above as a possible material. The composite material includes a film containing the above-mentioned acceptor material and a hole transport material. By applying a potential to the P-type layer 117, an electron transport layer Electrons are injected into the second electrode 102, which is the cathode, and holes are injected into the second electrode 102, which is the cathode, and the light-emitting device operates. In addition, since the organic compound according to one embodiment of the present invention has a low refractive index, it is a P-type By using this for layer 117, a light-emitting device with good external quantum efficiency can be obtained. .

[0134] In addition to the P-type layer 117, the charge generating layer 116 also includes an electron relay layer 118 and an electron injection buffer layer 119. Preferably, one or both of layers 119 are provided.

[0135] The electron relay layer 118 contains at least a substance having an electron transport property, and the electron injection buffer layer 1 The function of the junction is to prevent the interaction between the P-type layer 117 and the P-type layer 19 and to transfer electrons smoothly. The LUMO level of the substance having electron transport properties contained in the relay layer 118 is The LUMO level of the acceptor in the electron transport layer 114 and the charge generation layer 116 It is preferable that the LUMO level of the electron-relay layer 11 is between the LUMO level of the material contained in the adjacent layer. Specific energy levels of the LUMO levels of the electron transporting materials used in 8 is set to -5.0 eV or more, preferably -5.0 eV or more and -3.0 eV or less. The electron-transporting material used in the electron relay layer 118 is a phthalocyanine-based It is preferred to use materials or metal complexes having metal-oxygen bonds and aromatic ligands.

[0136] The electron injection buffer layer 119 may include an element selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, and These compounds (alkali metal compounds (oxides such as lithium oxide, halides, lithium carbonate, etc.) (including carbonates such as tium and cesium carbonate), alkaline earth metal compounds (oxides, halogens, etc.) compounds of rare earth metals (including oxides, halides, carbonates) or compounds of rare earth metals (including oxides, halides, carbonates) It is possible to use a material with high electron injection properties such as fluorine.

[0137] The electron injection buffer layer 119 is formed by containing a substance having an electron transporting property and a donor substance. In the case where the donor material is an alkali metal, an alkaline earth metal, or a rare earth metal, and their compounds (alkali metal compounds (oxides such as lithium oxide, halides , including carbonates such as lithium carbonate and cesium carbonate), alkaline earth metal compounds (oxides, compounds of rare earth metals (including oxides, halides, carbonates, etc.) In addition to tetrathianaphthalene (TTN), nickelocene, decamethine, An organic compound such as nickelocene can also be used. The electron transport layer 114 is preferably formed of the same material as that of the electron transport layer 114 described above. This can be done.

[0138] The material for forming the second electrode 102 is preferably one having a small work function (specifically, 3.8 eV or less). Bottom) Metals, alloys, electrically conductive compounds, and mixtures thereof can be used. Specific examples of such cathode materials include alkali metals such as lithium (Li) and cesium (Cs). Lithium metals, as well as magnesium (Mg), calcium (Ca), strontium (Sr), etc. Elements belonging to Group 1 or 2 of the Periodic Table of the Elements and alloys containing these elements (MgAg, Rare earth metals such as AlLi), europium (Eu), ytterbium (Yb) and the like However, when the second electrode 102 and the electron transport layer are provided with By providing an electron injection layer, the material can be used in a variety of applications, regardless of the magnitude of the work function. Various conductive materials such as indium oxide-tin oxide containing silicon oxide or silicon oxide are used as the second It can be used as the electrode 102. These conductive materials can be applied by dry methods such as vacuum deposition and sputtering, inkjet printing, It is possible to form the film by using a spin coating method, etc. Also, it is possible to form the film by using a wet sol-gel method. Alternatively, the metal material may be used in a wet process to form the metal layer.

[0139] The EL layer 103 can be formed by a variety of methods, including dry and wet methods. For example, vacuum deposition, gravure printing, offset printing, screen printing, etc. A printing method, an ink jet method, a spin coating method or the like may also be used.

[0140] Moreover, the above-mentioned electrodes or layers may be formed using different film formation methods.

[0141] The structure of the layers provided between the first electrode 101 and the second electrode 102 is the same as that described above. However, the light emitting region and the metal used in the electrode or carrier injection layer are not limited to the above. The first electrode 101 and the second electrode 102 are arranged so as to suppress quenching caused by the It is preferable to provide a light-emitting region where holes and electrons recombine at a location away from 02.

[0142] In addition, recombination in the hole transport layer or electron transport layer in contact with the light emitting layer 113, particularly in the light emitting layer 113 The carrier transport layer close to the region suppresses the energy transfer from excitons generated in the light-emitting layer. Therefore, the band gap is determined by the luminescent material constituting the luminescent layer or the luminescent material contained in the luminescent layer. It is preferable that the material is made of a substance having a larger band gap than the material. I wish.

[0143] Next, we developed a light-emitting device (a stacked element, a tandem element) that has a structure in which multiple light-emitting units are stacked. The embodiment of the light-emitting device (also referred to as a "light-emitting diode") will be described with reference to FIG. A light-emitting device having multiple light-emitting units between an electrode and a cathode. The EL layer 103 has a structure similar to that of the EL layer 103 shown in FIG. The light emitting device shown in FIG. 2(A) or The light-emitting device shown in FIG. 2(B) is a light-emitting device having one light-emitting unit. It can be said.

[0144] In FIG. 2C, a first light-emitting unit 511 and a second light-emitting unit 512 are disposed between an anode 501 and a cathode 502. The second light-emitting unit 512 is laminated, and the first light-emitting unit 511 and the second light-emitting unit A charge generating layer 513 is provided between the anode 501 and the cathode 502. These correspond to the first electrode 101 and the second electrode 102 in FIG. The same as described in the description of the first light-emitting unit 51 can be applied. The first and second light-emitting units 512 may have the same configuration or different configurations.

[0145] When a voltage is applied between the anode 501 and the cathode 502, the charge generating layer 513 generates a light emitting unit The luminescent unit has a function of injecting electrons into one luminescent unit and injecting holes into the other luminescent unit. In 2(C), when a voltage is applied so that the anode potential is higher than the cathode potential, In this case, the charge generating layer 513 injects electrons into the first light emitting unit 511 and Any device that injects holes into the gate 512 may be used.

[0146] The charge generation layer 513 is formed to have the same structure as the charge generation layer 116 described in FIG. 2B. The composite material of an organic compound and a metal oxide has the following advantages: Since the light-emitting unit has excellent characteristics, it can be driven at low voltage and low current. When the anode side surface of the charge generating layer 513 contacts the charge generating layer 513, the charge generating layer 513 becomes the light emitting unit. Since the EL element can also function as a hole injection layer for the light-emitting unit, the light-emitting unit does not need to have a hole injection layer. Both are good.

[0147] In addition, when the charge generating layer 513 is provided with the electron injection buffer layer 119, the electron injection buffer Since the anode layer 119 plays the role of an electron injection layer in the light-emitting unit on the anode side, the light-emitting The unit does not necessarily need to have an electron injection layer.

[0148] Although the light-emitting device having two light-emitting units has been described in FIG. 2C, the light-emitting device having three or more light-emitting units may be used. The same can be applied to a light-emitting device in which the above light-emitting units are stacked. As in the light-emitting device according to the present embodiment, a plurality of light-emitting units are electrically connected between a pair of electrodes. By separating the layers with the generation layer 513, high-luminance light emission is possible while keeping the current density low. This allows the realization of a light-emitting device with a longer life. In addition, it can be driven at a low voltage and consumes less power. A light emitting device can be realized.

[0149] FIG. 3 shows a light-emitting device having a plurality of light-emitting units according to an embodiment of the present invention, similar to FIG. 2(C). FIG. 1 is a schematic diagram of a light-emitting device when the light-emitting device is applied in the above manner. A first light-emitting unit 511 having a first light-emitting layer 113-1 and a second light-emitting layer 113-2 A second light-emitting unit 512 having a charge generating layer 513 is laminated on the second light-emitting unit 512 via a charge generating layer 513 . The light emitted from the light emitting device is emitted directly or via the color conversion layer 205. Furthermore, color purity may be improved through color filters 225R, 225G, and 225B. In addition, in FIG. 3, a configuration in which the color filter 225B is provided is illustrated, but the present invention is not limited to this. For example, in FIG. 3, instead of the color filter 225B, an overcoat The overcoat layer may be made of an organic resin material, typically, Acrylic resin or polyimide resin may be used. The filter layer may be called a colored layer, and the overcoat layer may be called a resin layer. The color filter 225R is a first colored layer, and the color filter 225G is a second colored layer. These may also be referred to as layers.

[0150] In addition, the above-mentioned EL layer 103, the first light-emitting unit 511, the second light-emitting unit 512, and Each layer such as the charge generating layer and the electrodes can be formed by, for example, a deposition method (including a vacuum deposition method), a droplet discharge method (including an inkjet method), etc. It can be formed by using methods such as ink jet printing, coating, and gravure printing. They can be used in a wide range of applications, including low molecular weight materials, medium molecular weight materials (including oligomers and dendrimers), and or a polymeric material.

[0151] Here, when we look at the color reproducibility of full-color displays, To achieve this, it is essential to obtain light with good color purity. Compared to the emission from Spectrum using a micro-resonant structure (microcavity structure) to obtain light emission with It is preferable that the line narrowing is performed.

[0152] In fact, in a light-emitting device in which a microresonator structure is appropriately applied using appropriate dopants, The wide range of Rec.2020 color gamuts defined in the BT.2020 and BT.2100 standards In this case, the light-emitting device has a micro-resonant structure. However, by having a configuration that strengthens blue light, it is possible to obtain a light emitting device with good color purity and high efficiency. This can be done.

[0153] The light-emitting device having a microresonator structure is configured such that a pair of electrodes of the light-emitting device is a reflective electrode and a semi-transmissive electrode. The reflective electrode and the semi-transmissive and semi-reflective electrode are as described above. These correspond to the first electrode 101 and the second electrode 102 of the above-mentioned structure, one of which is a reflective electrode and the other is a semi-transparent electrode. A semi-reflective electrode may be used.

[0154] Light-emitting devices with microresonator structures emit light in all directions from the light-emitting layer contained in the EL layer. The emitted light is reflected by the reflective electrode and the semi-transparent and semi-reflective electrode, and resonates, forming a certain wavelength. The light is amplified and becomes directional.

[0155] The reflectance of the reflective electrode to visible light is 40% to 100%, preferably 70% to 100%. and resistivity is 1×10 -2 The material for forming the reflective electrode is Examples of the alloy containing aluminum (Al) include aluminum (Al) and alloys containing Al. is Al and L (L is titanium (Ti), neodymium (Nd), nickel (Ni), and lanthanum) Examples of the alloy include an alloy containing Al and Ti, and an alloy containing La. Or an alloy containing Al, Ni, and La. Aluminum has low resistance and low light reflection. In addition, aluminum is abundant in the earth's crust and is inexpensive, so The use of nium can reduce the manufacturing cost of light-emitting devices. (Ag), or Ag and N (N is yttrium (Y), Nd, magnesium (Mg), Ytterbium (Yb), Al, Ti, Gallium (Ga), Zinc (Zn), Indium ( In), tungsten (W), manganese (Mn), tin (Sn), iron (Fe), Ni, copper (Cu), palladium (Pd), iridium (Ir), or gold (Au) As an alloy containing silver, for example, a silver-palladium alloy may be used. Alloys containing aluminum and copper, alloys containing silver and copper, alloys containing silver and magnesium, alloys containing silver and nickel Examples of such alloys include those containing silver and gold, those containing silver and ytterbium, etc. Using transition metals such as tungsten, chromium (Cr), molybdenum (Mo), copper, and titanium It is possible.

[0156] In addition, a light-transmitting conductive material is provided between the reflective electrode and the EL layer 103 as an optical path length adjustment layer. A transparent electrode layer may be formed, and the first electrode 101 may be formed of two layers, a reflective electrode and a transparent electrode. By using a transparent electrode layer, it is also possible to adjust the optical path length (cavity length) of the microresonant structure. As a conductive material with optical transparency, indium tin oxide (InT Indium tin oxide (ITO), silicon or silicon oxide ITSO), Indium Zinc Oxide, Titanium Indium-tin oxide, indium-titanium oxide, and tungsten oxide containing and metal oxides such as indium oxide containing zinc oxide.

[0157] The semi-transmissive / semi-reflective electrode has a visible light reflectance of 20% to 80%, preferably 40% to 70%. %, and the resistivity is 1×10 -2 The semi-transparent and semi-reflective electrodes are The conductive layer may be formed by using one or more conductive metals, alloys, conductive compounds, etc. Specifically, for example, indium tin oxide (InTinOxide) , ITO), indium tin oxide containing silicon or silicon oxide (ITSO), Indium Zinc Oxide, an oxide containing titanium Indium-tin oxide, indium-titanium oxide, tungsten oxide and zinc oxide Metal oxides such as indium oxide containing indium can be used. A thin metal film having a thickness of 1 nm or more and 30 nm or less can be used. Examples of metals include Ag, Ag and Al, Ag and Mg, Ag and Au, and Ag and Yb. Any alloy can be used.

[0158] The reflective electrode and the semi-transmissive / semi-reflective electrode are either the first electrode 101 or the second electrode 102. In addition, it may be either an anode or a cathode.

[0159] In the case of a light emitting device having a top emission structure, the E By providing an organic cap layer on the surface opposite to the surface in contact with the L layer 103, the light extraction efficiency is improved. By providing an organic capping layer, the refraction at the electrode-air interface can be reduced. The difference in the refractive index can be reduced, improving the light extraction efficiency. The thickness is preferably 0 nm or less. More preferably, the thickness is 30 nm or more and 90 nm or less. The cap layer is preferably an organic compound layer having a molecular weight of 300 to 1200. The semi-transmissive / semi-reflective electrode is preferably an organic material having a certain degree of transparency. In order to maintain the organic capping, the film thickness must be thinned, which may result in poor electrical conductivity. By using a conductive material for the layer, the light extraction efficiency is improved while ensuring conductivity. This can improve the yield of light-emitting device production. For the organic cap layer, an organic compound having a low solubility in the EL layer 103 can be preferably used. In this case, the organic compound used in forming the EL layer 103 may be used. Since the organic capping layer can be formed in the deposition chamber, the organic capping layer can be formed easily. can be done.

[0160] The light-emitting device includes a transparent electrode provided in contact with the reflective electrode, a hole injection layer, a hole By changing the thickness of the carrier transport layer, the optical distance between the reflective electrode and the semi-transparent / semi-reflective electrode can be adjusted. This allows the reflective electrode and the semi-transmissive / semi-reflective electrode to be changed. Between these, the light of the resonating wavelength can be strengthened and the light of the non-resonating wavelength can be attenuated. .

[0161] The micro-resonant structure (microcavity structure) is a structure in which the interface between the reflective electrode and the EL layer is The optical distance (optical path length) between the semi-reflective electrode and the EL layer side interface is λn If m, it is preferable that it is an integer multiple of λ / 2.

[0162] In addition, the light that is reflected by the reflective electrode and returned (first reflected light) is This causes a large interference with the light (first incident light) that is directly incident on the semi-transmissive / semi-reflective electrode from the layer. The optical distance between the reflective electrode and the light-emitting layer is (2n-1)λ / 4 (where n is a natural number greater than or equal to 1). It is preferable to adjust the optical path length so that the wavelength of the emitted light is amplified. This causes the phases of the first reflected light and the first incident light to match, thereby amplifying the light emitted from the light-emitting layer. It is possible.

[0163] The microcavity structure makes it possible to enhance the emission intensity of a specific wavelength in the forward direction. This allows for lower power consumption. Also, the probability of light entering the color conversion layer is increased. It can be done.

[0164] By the way, the light narrowed by the microcavity structure has a strong directivity perpendicular to the screen. On the other hand, the light passing through the color conversion layer using the above QDs is The light emitted from QDs and light-emitting organic compounds is emitted in all directions, so the directionality is Almost none. The light emitted from the light-emitting device is slightly lost through the color conversion layer, so there is little color change. In displays using a photoconductive layer, blue light, which has the shortest wavelength, is emitted from the light-emitting device. The green and red light is obtained directly from the pixel, and the green and red light is obtained through the color conversion layer. In addition, a difference in light distribution characteristics occurs between red pixels and blue pixels. The large difference in light distribution characteristics creates viewing angle dependency, which directly leads to deterioration of display quality. The impact is particularly noticeable when the content is viewed on a large screen, such as in a television, and by a large group of people.

[0165] In view of this, in the light-emitting device according to one embodiment of the present invention, a function of diffusing light to pixels not passing through a color conversion layer is provided. A structure having a color conversion layer is provided, or a structure that provides directivity to pixels via a color conversion layer is provided. The configuration may be as follows.

[0166] The structure having the function of diffusing light is used to prevent the light emitted from the light-emitting device from escaping to the outside of the light-emitting device. The light emitted from the light-emitting device having the microresonator structure is Although it has strong directivity, it is diffused by a structure that has the function of diffusing the light. It can be used to weaken the light or to make the diffused light directional. In this case, the light passing through the color conversion layer and the light not passing through the color conversion layer can have the same orientation characteristics. This makes it possible to reduce the viewing angle dependency.

[0167] 4A to 4C, the first pixel 208B emits light from the first light-emitting device 207B. The first light-emitting device has a structure 205B having a function of scattering light. The structure 205B having the function of scattering light emitted from 207B is shown in FIG. B) a layer including a first material that scatters light emitted from the first light-emitting device; As shown in FIG. 4(C), the structure has a structure for scattering light emitted from the first light-emitting device. It may be composed of.

[0168] FIG. 5(A) to (C) show modified examples. FIG. 5(A) shows the light in FIG. Instead of the structure 205B having the scattering function, a structure having a function of a blue color filter is provided. Also, in Fig. 5(B) and (C), the light scattering layer (color filter 215B) is 2 shows an embodiment having both a structure 205B having a disturbing function and a blue color filter 215B. The blue color filter 215B scatters light as shown in FIGS. 5(B) and 5(C). Alternatively, it may be formed in contact with the structure 205B having the function of forming the insulating film 205, or may be formed on another structure such as a sealing substrate. As a result, the light emitting device can scatter light with directionality while improving color purity. In addition, the reflection of external light can be suppressed, resulting in a better display. can.

[0169] Light from the first pixel 208B passes through the structure 205B, which receives light from the first light emitting device 207B. By emitting the light through a filter, it is possible to make the light less directional. This reduces the difference in light distribution characteristics due to the difference in the light intensity, and makes it possible to provide a light emitting device with high display quality.

[0170] In the light-emitting device according to one embodiment of the present invention shown in FIGS. 6(A) and 6(B), Means 210G and 210R for providing directionality to the light emitted from the first color are provided. Any means may be used to impart directionality to the light emitted from the conversion layer. For example, a color change A semi-transmissive semi-reflective layer is formed so as to sandwich the exchange layer, and a micro-resonator structure is formed. FIG. 6(A) shows a state in which semi-transmissive and semi-reflective layers are formed above and below the color conversion layer, and FIG. 6(B) shows the light emission from the color conversion layer. The semi-transmissive semi-reflective layer on the device side is also used as the second electrode (semi-transmissive semi-reflective electrode) of the light-emitting device. This is the situation.

[0171] The light from the second pixel 208G and the third pixel 208R is directed toward the light emitted from the color conversion layer. By providing the means 210G and 210R for imparting the light with high directivity, the light can be made highly directional. This makes it possible to reduce the difference in light distribution characteristics depending on the color, resulting in light emission with high display quality. The present invention can be an apparatus.

[0172] (Embodiment 2) In this embodiment, the hole injection layer 111 and An organic compound having a hole transporting property that can be used for the hole transport layer 112 will be described. do.

[0173] Among organic compounds that have carrier transport properties and can be used in organic EL devices, One of the materials with a small refractive index is 1,1-bis-(4-bis(4-methylphenyl)-aryl)- The most well-known is TAPC, which has a small refractive index. By using this material in the EL layer, it is possible to obtain a light-emitting device that exhibits high external quantum efficiency. Therefore, the use of TAPC can lead to light-emitting devices with good external quantum efficiency. It is expected that...

[0174] Usually, there is a trade-off between high carrier transport and low refractive index. The carrier transport properties of the compound are largely due to the presence of unsaturated bonds. This is because organic compounds with a large amount of TAPC tend to have a high refractive index. It is a material that has an excellent balance between transport properties and a low refractive index. In the case of compounds with a 1,1-disubstituted structure of cyclohexane such as TAPC, Since two bulky substituents are inserted on one carbon atom of hexane, steric repulsion is large. This leads to instability of the molecules themselves, which is disadvantageous in terms of reliability. In addition, TAPC has a structure consisting of cyclohexane and a simple benzene ring. As a result, the glass transition point (Tg) was low and there were problems with heat resistance.

[0175] One method to obtain a highly heat-resistant and reliable hole transport material is the unsaturated carbonization. It is possible to introduce hydrogen groups, especially cyclic unsaturated hydrocarbon groups, into the molecule. In order to obtain a material with a low refractive index, it is preferable to introduce a substituent with a low molecular refraction into the molecule. Examples of the substituent include a saturated hydrocarbon group and a cyclic saturated hydrocarbon group.

[0176] In addition, the materials used as carrier transport materials in organic EL devices have high carrier transport properties. It is preferable that the compound has a skeleton, and among them, an aromatic amine skeleton is preferable because it has a high hole transporting property. In order to further improve the carrier transport properties, the introduction of two amine groups was also considered. However, as with the above-mentioned TAPC, depending on the environment of the substituents placed around it, However, the diamine structure may be detrimental to reliability.

[0177] Overcoming the trade-off, this material combines carrier transport, a low refractive index, and high reliability. As a compound that can be used for this purpose, the present inventors have developed a compound that forms bonds with sp3 hybrid orbitals that constitute a saturated hydrocarbon group. In particular, the present inventors have found a monoamine compound in which the ratio of carbon atoms contained in the monoamine falls within a certain range. The compound has good reliability comparable to conventional hole injection layer materials with normal refractive index. The material is a monoamine compound having a carbon atom that forms a bond with an sp3 hybrid orbital. By optimizing the number and position of the substituents, it is possible to create a material with better properties. It is possible.

[0178] That is, the organic compound according to one embodiment of the present invention has a first aromatic ring, a second aromatic ring, and a third aromatic ring. A monoamine compound in which the ring is directly attached to the nitrogen atom of the amine, A hole transport layer of an organic electroluminescence device, the layer being made of the compound and having a refractive index of 1.5 or more and 1.75 or less. The monoamine compound is a material for a hole injection layer and a material for a hole injection layer. The proportion of carbon atoms that form bonds with sp3 hybrid orbitals is 23% to 55%. preferable.

[0179] Substituents that consist of carbon atoms that form bonds with sp3 hybrid orbitals are so-called saturated hydrocarbon groups. Because it is a cyclic saturated hydrocarbon group, the molecular refraction is low. Therefore, the bond is formed by sp3 hybrid orbitals. The monoamine in question is one in which the carbon atoms making up 23% to 55% of the total carbon atoms in the molecule. The compound can be used as a material for a hole transport layer and a hole injection layer having a small refractive index. can be done.

[0180] The monoamine compound is 1 The results of H-NMR measurements showed that the concentration was less than 4 ppm. It is preferred that the integral of the signal at or below 4 ppm exceeds the integral of the signal at or above 4 ppm. Signals below ppm represent linear or cyclic saturated hydrocarbon groups, and their integrals are less than 4 ppm. If the integral value of the signal exceeds the value above, the number of hydrogen atoms constituting the saturated hydrocarbon group is This means that there are more hydrogen atoms than make up the unsaturated hydrocarbon. The ratio of carbon atoms that form bonds only with sp3 hybrid orbitals can be estimated. The carbon atom of a hydrocarbon group has fewer bonds that can bond with hydrogen. For example, In terms of hexane, C6H6 and C6H 12 Considering this difference,1 HN In the MR measurement, the integral value of the signal below 4 ppm is 4 ppm or more. The signal exceeds the integral value, which means that the carbon that makes up the molecule is saturated hydrocarbons. This indicates that about one-third of the carbon atoms in the group are in the molecule. As a result, the monoamine compound becomes an organic compound with a small refractive index, and is useful as a material for a hole transport layer and The compound can also be suitably used as a material for a hole injection layer.

[0181] In addition, the monoamine compound preferably has at least one fluorene skeleton. The hole transport property of the monoamine compound having a fluorene skeleton is improved, and the monoamine The compound was used as either or both of the hole transport layer material and the hole injection layer material. The light emitting device can be a light emitting device with a good driving voltage. The fluorene skeleton is any one of the first aromatic ring, the second aromatic ring, and the third aromatic ring. The direct bond to the nitrogen atom of the amine contributes to shallowing the HOMO level of the molecule. This is preferable because it makes it easier to transfer holes.

[0182] When the monoamine compound is formed into a film by vapor deposition, its molecular weight is 400 or more. It is preferable that it is 1000 or less.

[0183] The above monoamine compounds will now be described in more detail.

[0184] The monoamine compound has a first aromatic ring, a second aromatic ring and a third aromatic ring attached to a nitrogen atom of an amine. The aromatic ring is a triarylamine derivative. The ring is attached to the nitrogen atom of the amine.

[0185] The first aromatic ring and the second aromatic ring each independently have one to three benzene rings. In addition, both the first aromatic ring and the second aromatic ring are preferably hydrocarbon rings.

[0186] When the first aromatic ring and the second aromatic ring each have two or three benzene rings, two or It is preferable that the three benzene rings are bonded to each other as substituents. The first aromatic ring and the second aromatic ring are each a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, A phenyl group is preferred.

[0187] Either or both of the first aromatic ring and the second aromatic ring have 1 to 12 carbon atoms. It has one or more hydrocarbon groups in which carbon is bonded only through sp3 hybrid orbitals. There are.

[0188] The monoamine compound may have either a first aromatic ring or a second aromatic ring, or both. Hydrocarbons having 1 to 12 carbon atoms and in which the carbons form bonds only through sp3 hybrid orbitals The total number of carbon atoms contained in the above hydrocarbon group that are bonded to one aromatic ring is 6 or more, and the above-mentioned hydrocarbon group bonded to the first aromatic ring and the second aromatic ring The total number of carbon atoms contained in the polymer is 8 or more, preferably 12 or more. By bonding the hydrocarbon group in this manner, the monoamine compound has a refractive index The organic compound may be a small compound.

[0189] The total number of carbon atoms contained in the hydrocarbon group bonded to the first aromatic ring and the second aromatic ring is In order to maintain good carrier transportability, it is preferable that the value is 36 or less, and more preferably 30 or less. As mentioned above, the more π electrons derived from the unsaturated bonds of carbon atoms, the more carriers there are. This is advantageous for transportation.

[0190] The above-mentioned hydrocarbon group has 1 to 12 carbon atoms and forms bonds only through sp3 hybrid orbitals. is preferably an alkyl group having 3 to 8 carbon atoms and a cycloalkyl group having 6 to 12 carbon atoms. Specifically, propyl group, isopropyl group, butyl group, sec-butyl group, isobutyl group, group, tert-butyl group, pentyl group, isopentyl group, sec-pentyl group, tert -pentyl, neopentyl, hexyl, isohexyl, sec-hexyl, t ert-hexyl, neohexyl, heptyl, octyl, cyclohexyl, 4 -Methylcyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, decahydronaphthyl group, cycloundecyl group, cyclododecyl group, etc. can be used, in particular t-butyl, cyclohexyl and cyclododecyl groups. preferable.

[0191] The third aromatic ring is a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted cyclic ring or less. As the number of rings in the condensed ring increases, the refractive index tends to increase. This allows the refractive index to be kept low. Similarly, when the number of condensed rings increases, Since the absorption and emission of light in the visible region can be observed, materials that are less affected by absorption and emission In addition, in order to maintain a low refractive index, the third aromatic ring can be The number of the aromatic rings that can be used as the third aromatic ring is preferably 6 to 13. Specific examples of the ring include a benzene ring, a naphthalene ring, a fluorene ring, and an acenaphthylene ring. In particular, the third aromatic ring is preferably a fluoro group because it has good hole transport properties. It is preferable that the alkylene group contains an olefin ring, and more preferable that the alkylene group is a fluorene ring.

[0192] The monoamine compound having the above-mentioned structure has a hole transporting property and a small refractive index. Since it is a compound, it can be used as a material for the hole transport layer or hole injection layer of an organic EL device. In addition, the hole transport layer material or the hole injection layer material can be preferably used. The organic EL device has a hole transport layer and a hole injection layer with a small refractive index. The device has high luminous efficiency, i.e., external quantum efficiency, current efficiency and blue index. In addition, a functional material using the hole transport layer material or the hole injection layer material can be used. In the organic EL device, the material for the hole transport layer or the material for the hole injection layer is a monoamine compound. This limits the number of aromatic rings attached to the saturated hydrocarbon group, thereby reducing steric repulsion. By doing so, it is possible to improve the stability of the molecule, resulting in a light-emitting device with a long life. It can be said that

[0193] Among the above monoamine compounds, the organic compound represented by the following general formula (G1) is particularly preferred. preferable.

[0194] [ka]

[0195] In the above general formula (G1), Ar 1 , Ar 2 each independently represents a benzene ring, Or it represents a substituent in which two or three benzene rings are bonded to each other. 1 , Ar 2 year Specifically, the alkyl group includes a phenyl group, a biphenyl group, a terphenyl group, a naphthylphenyl group, etc. In order to lower the refractive index and maintain the carrier transport property of the nitrogen atom, phenyl is used. The group is particularly preferred.

[0196] In addition, Ar 1 , Ar 2 In one or both of the above, carbon is bonded only with sp3 hybrid orbitals. The hydrocarbon group has one or more hydrocarbon groups having 1 to 12 carbon atoms. The total number of carbon atoms is 8 or more, and Ar 1 and Ar 2 Before binding to at least one of The total number of carbon atoms in the hydrocarbon group is 6 or more. The carbon atoms form bonds only with sp3 hybrid orbitals. The hydrocarbon group having 1 to 12 carbon atoms is preferably an alkyl group having 3 to 8 carbon atoms, and more preferably an alkyl group having 3 to 8 carbon atoms. Cycloalkyl groups having 6 to 12 carbon atoms are preferred. Specifically, propyl groups, isopropyl groups, butyl group, sec-butyl group, isobutyl group, tert-butyl group, pentyl group, Isopentyl, sec-pentyl, tert-pentyl, neopentyl, hexyl hexyl, isohexyl, sec-hexyl, tert-hexyl, neohexyl, Heptyl group, octyl group, cyclohexyl group, 4-methylcyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, decahydronaphthyl group, Cycloundecyl and cyclododecyl groups can be used, particularly t-butyl. The cyclohexyl and cyclododecyl groups are preferred.

[0197] In addition, Ar 1 or Ar 2 The hydrocarbon group is a linear alkyl group having 1 or 2 carbon atoms. When a plurality of linear alkyl groups are bonded, the linear alkyl groups may be bonded to each other to form a ring.

[0198] In addition, in the above general formula (G1), R 1 and R 2 each independently represents an alkyl group having 1 to 4 carbon atoms; R represents an alkyl group. 1 and R 2 may be bonded to each other to form a ring. 3 represents an alkyl group having 1 to 4 carbon atoms; and u is an integer of 0 to 4.

[0199] Further, the organic compound of one embodiment of the present invention is represented by the following general formula (G2) to general formula (G4). It is also possible.

[0200] [ka]

[0201] In the above general formula (G2), n, m, p and r each independently represent 1 or 2. In addition, s, t, and u each independently represent an integer of 0 to 4. In addition, n+p and m+r each Each of s, t, and u is independently 2 or 3. In addition, s, t, and u are each independently 0. is preferred.

[0202] In the above general formula (G2), R 1 , R 2 and R 3 each independently represents an alkyl group having 1 to 4 carbon atoms; R represents the alkyl group. 4 and R 5 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms The hydrocarbon group having 1 to 3 carbon atoms is a methyl group, an ethyl group, a propyl group, or the like. Examples of the hydrocarbon group having 1 to 4 carbon atoms include, in addition to the above, a bromine group, etc. Mention may be made of the ethyl group.

[0203] Also, R 10 ~R 14 and R 20 ~R 24 each independently represents hydrogen or a group having 1 to 10 carbon atoms 12 represents a hydrocarbon group in which carbon is bonded only with sp3 hybrid orbitals. Hydrocarbon groups with 1 to 12 carbon atoms that form bonds only through C3 hybrid orbitals include those with 3 or more carbon atoms. Alkyl groups having up to 8 carbon atoms and cycloalkyl groups having 6 to 12 carbon atoms are preferred. Propyl group, isopropyl group, butyl group, sec-butyl group, isobutyl group, tert- Butyl group, pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, Neopentyl, hexyl, isohexyl, sec-hexyl, tert-hexyl aryl, neohexyl, heptyl, octyl, cyclohexyl, 4-methylcyclohexyl Hexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, Decahydronaphthyl, cycloundecyl, and cyclododecyl groups can be used. Of these, t-butyl, cyclohexyl and cyclododecyl groups are particularly preferred.

[0204] In addition, R 10 ~R 14 and R 20 ~R 24 The total number of carbon atoms contained in is 8 or more, And R 10 ~R 14 or R 20 ~R 24 The total number of carbon atoms in at least one of is assumed to be 6 or greater.

[0205] In the above general formula (G2), when n is 2, the types of substituents of the two phenylene groups are The number of substituents and the positions of the bonds may be the same or different. When m is 2, The types of substituents, the number of substituents, and the positions of bonds of the two phenylene groups are the same. When p is 2, the types of substituents on the two phenyl groups may be different. The number of substituents and the positions of the bonds may be the same or different. When r is 2, The types of substituents, the number of substituents, and the positions of the bonds of the two phenyl groups are the same. may also be different.

[0206] When s is an integer from 2 to 4, a plurality of R 4 may be the same or different Preferably, when t is an integer from 2 to 4, a plurality of R 5 may be the same or different Preferably, when u is an integer from 2 to 4, a plurality of R 3 may be the same or different Good. In addition, R 1 and R 2 may be bonded to each other to form a ring, R 4 , R 5 , R 10 ~R 14 and R 20 ~R 24 In the formula, adjacent groups are bonded to each other to form a ring. That's fine.

[0207] [ka]

[0208] In the above general formula (G3), R 1 , R 2 and R 3 each independently represents a group having 1 to 1 carbon atoms R represents an alkyl group of 4; 4 represents either hydrogen or a hydrocarbon group having 1 to 3 carbon atoms. Examples of the hydrocarbon group having 1 to 3 carbon atoms include a methyl group, an ethyl group, and a propyl group. In addition to the above, examples of the hydrocarbon group having 1 to 4 carbon atoms include a butyl group. This can be done.

[0209] n and p each independently represent 1 or 2, and s and u each independently represent an integer from 0 to 4. Here, n+p is 2 or 3. It is preferable that s and u are each independently 0. I wish.

[0210] Also, R 10 ~R 14 and R 20 ~R 24 each independently represents hydrogen or a group having 1 to 10 carbon atoms 12 represents a hydrocarbon group in which carbon is bonded only with sp3 hybrid orbitals. Hydrocarbon groups with 1 to 12 carbon atoms that form bonds only through C3 hybrid orbitals include those with 3 or more carbon atoms. Alkyl groups having up to 8 carbon atoms and cycloalkyl groups having 6 to 12 carbon atoms are preferred. Propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, cyclohexyl group Cyclyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclo Lowendecyl and cyclododecyl groups can be used, and in particular t-butyl groups, Cyclohexyl and cyclododecyl groups are preferred.

[0211] However, R 10 ~R 14 and R 20 ~R 24 The total number of carbon atoms in , and R 10 ~R 14 or R 20 ~R 24 The total carbon contained in at least one of The number must be 6 or greater.

[0212] When n is 2, the types of the substituents on the two phenylene groups, the number of the substituents and the bond The positions of the bonds may be the same or different. When p is 2, the positions of the two phenyl groups The types of substituents, the number of substituents, and the positions of bonds may be the same or different. In addition, when s is an integer from 2 to 4, a plurality of R 4 Although each is the same, they are different. When u is an integer from 2 to 4, a plurality of R 3 may be the same or different Good. In addition, R 1 and R 2 may be bonded to each other to form a ring, R 4 , R 10 No To R 14 and R 20 ~R 24 Adjacent groups may be bonded to each other to form a ring. stomach.

[0213] [ka]

[0214] In the above general formula (G4), u represents an integer of 0 to 4. It is preferable that u is 0. I wish.

[0215] Also, R 10 ~R 14 and R 20 ~R 24 each independently represents hydrogen or a group having 1 to 10 carbon atoms 12 represents a hydrocarbon group in which carbon is bonded only with sp3 hybrid orbitals. Hydrocarbon groups with 1 to 12 carbon atoms that form bonds only through C3 hybrid orbitals include those with 3 or more carbon atoms. Alkyl groups having up to 8 carbon atoms and cycloalkyl groups having 6 to 12 carbon atoms are preferred. Propyl group, isopropyl group, butyl group, sec-butyl group, isobutyl group, tert- Butyl group, pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, Neopentyl, hexyl, isohexyl, sec-hexyl, tert-hexyl aryl, neohexyl, heptyl, octyl, cyclohexyl, 4-methylcyclohexyl Hexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, Decahydronaphthyl, cycloundecyl, and cyclododecyl groups can be used. Of these, t-butyl, cyclohexyl and cyclododecyl groups are particularly preferred.

[0216] However, R 10 ~R 14 and R 20 ~R 24 The total number of carbon atoms in , and R 10 ~R 14 or R 20 ~R 24 The total carbon contained in at least one of The number must be 6 or greater.

[0217] Also, R 1 , R 2 and R 3 Each independently represents an alkyl group having 1 to 4 carbon atoms. is an integer from 2 to 4, a plurality of R 3 may be the same or different. , R 1 and R 2 may be bonded to each other to form a ring, R 10 ~R 14 and R 20 ~R 24 Adjacent groups may be bonded to each other to form a ring.

[0218] In the above general formulae (G2) to (G4), R 10 ~R 14 and R 20 ~R 24 teeth each independently being any one of hydrogen, tert-butyl, and cyclohexyl; is preferable in order to reduce the refractive index. R 10 ~R 14 At least 3 of and R 20 ~R 24 At least three of the This is preferable because it does not impede the transportability of carriers.

[0219] Also, R 10 , R 11 , R 13 , R 14 , R 20 , R 21 , R 23 and R 24 is hydrogen Yes, R 12 and R 22 is preferably a cyclohexyl group.

[0220] Also, R 10 , R 12 , R 14 , R 20 , R 21 , R 23 and R 24 is hydrogen and R 11 and R 13 is a tert-butyl group, and R 22 is a cyclohexyl group. preferable.

[0221] Also R 10 , R 12 , R 14 , R 20 , R 22 and R 24 is hydrogen and R 11 , R 1 3 , R 21 and R 23 is preferably a tert-butyl group.

[0222] The organic compound of one embodiment of the present invention having the above structure has a hole-transport property and a small refractive index. Since it is a small organic compound, it is effective to use it for the hole transport layer 112. The organic compound according to one embodiment of the present invention is a positive electrode using a film in which the organic compound is mixed with an acceptor substance. It can be used as a hole injection layer 111. In addition, the organic EL device using the organic compound The device has a hole transport layer and a hole injection layer with a small refractive index, so that the light emission Light-emitting devices with high efficiency, i.e., high external quantum efficiency, current efficiency and blue index. In addition, an organic EL device using the organic compound can be Since it is a monoamine compound, it can be used to produce a light-emitting device with a long life.

[0223] Furthermore, the organic compound can also be used as a host material. By co-evaporating the electron transport material, the excitation light generated by the electron transport material and the hole transport material is generated. A complex may be formed. By forming an exciplex having an appropriate emission wavelength, This allows for efficient energy transfer to the light-emitting material, resulting in a light-emitting material with high efficiency and a long life. It is possible to provide an optical device.

[0224] Next, a method for synthesizing the above-mentioned monoamine compound will be illustrated. This is merely an example of a synthesis method, and the synthesis method is not necessarily limited to this method.

[0225] [ka]

[0226] As shown in the synthesis scheme below, 9,9-disubstituted-9H-fluorenylamine (A) and The organic halide (X1) and (X2) are reacted with a metal catalyst, a metal, or a metal compound in the presence of a base. By coupling with a coupling agent, an organic compound represented by general formula (G1) is obtained. This can be done.

[0227] [ka]

[0228] In the above synthesis scheme, Ar 1 , Ar 2 are each independently a substituted or unsubstituted benzo represents a benzene ring or a substituent in which two or three benzene rings are bonded to each other. 1 , Ar 2 One or both of the carbon atoms are bonded only by sp3 hybrid orbitals. 1 to 12, one or more hydrocarbon groups, Ar 1 and Ar 2 The hydrocarbon bonded to The total number of carbon atoms contained in the group is 8 or more, and 1 and Ar 2 At least one of The total number of carbon atoms contained in the bonded hydrocarbon groups is 6 or more. 1 or Ar 2 When a plurality of linear alkyl groups having 1 or 2 carbon atoms are bonded to the hydrocarbon group, The linear alkyl groups may be bonded to each other to form a ring. In R 1 and R 2 Each independently represents an alkyl group having 1 to 4 carbon atoms. 1 and R 2may be bonded to each other to form a ring. 3 is an arsenic compound having 1 to 4 carbon atoms. represents an alkyl group, and u is an integer from 0 to 4. X represents a halogen element or a triflate. The group is shown.

[0229] When the above synthesis reaction is carried out by the Buchwald-Hartwig reaction, X is a halogen atom. or a triflate group. The halogen element is preferably iodine, bromine or chlorine. In this reaction, bis(dibenzylideneacetone)palladium(0) and allylparaben chloride are used. Palladium complexes or compounds such as palladium dimer(II) and tri(tert-butyl) t-butyl)phosphine and di-tert-butyl(1-methyl-2,2-diphenylsilyl)phosphine. Paradiphenylphosphine with ligands such as cyclopropylphosphine and tricyclohexylphosphine The catalyst used is sodium tert-butoxide or other organic bases. In the case of using a solvent, an inorganic base such as toluene or cesium carbonate can be used. benzene, xylene, 1,3,5-trimethylbenzene, etc. can be used. By increasing the temperature to 120°C or higher, arylene containing a low-cycle halogen element (e.g., chlorine) can be obtained. Since the reaction between the aryl group and the amine proceeds in a short time and in a high yield, it is more preferable to use a compound having high heat resistance. Xylene or 1,3,5-trimethylbenzene will be used.

[0230] When the synthesis is carried out by the Ullmann reaction, X represents a halogen element. The element is preferably iodine, bromine, or chlorine. The catalyst is preferably copper or a copper compound. It is preferable to use copper(I) iodide or copper(II) acetate. Examples of the solvent include inorganic bases such as potassium carbonate. 3,4,5,6-Tetrahydro-2(1H)pyrimidinone (DMPU), N-methyl-2 -pyrrolidone (NMP), toluene, xylene, 1,3,5-trimethylbenzene, etc. In the Ullmann reaction, the reaction temperature is 100°C or higher, which allows the reaction to proceed in a shorter time and at a higher temperature. The desired product can be obtained in high yields, so DMPU, NMP, 1,3,5-trimethylbenzaldehyde, and 1,3,5-trimethylbenzaldehyde, which have high boiling points, are used. It is preferable to use benzene. The reaction temperature is more preferably 150° C. or higher. Therefore, it is more preferable to use DMPU.

[0231] As described above, the organic compound of general formula (G1) can be synthesized.

[0232] (Embodiment 3) In this embodiment mode, a display device using the light-emitting device described in Embodiment 1 will be described.

[0233] In this embodiment, a display device manufactured using the light-emitting device described in Embodiment 1 will be described. The following description will be given with reference to FIG. 7. FIG. 7(A) is a top view showing a display device, and FIG. 7(B) is a bottom view showing a display device. FIG. 1 is a cross-sectional view taken along the lines AB and CD in FIG. The driving circuit section (source line driving circuit) 601 shown by the dotted line controls the pixel section 602 includes a driving circuit section (gate line driving circuit) 603. Also, 604 is a sealing substrate. 605 is a seal material, and the inside surrounded by the seal material 605 is a space 607. .

[0234] The lead wiring 608 is connected to the source line driver circuit 601 and the gate line driver circuit 603. The wiring is for transmitting the signals to be input, and the FPC (flexible printed circuit board) is the external input terminal. Video signal, clock signal, start signal, reset signal, etc. from the 609 Although only the FPC is shown here, the FPC has a printed wiring board. The light emitting device in this specification may be a light emitting device. This includes not only the device itself, but also the state in which an FPC or PWB is attached to it. do.

[0235] Next, the cross-sectional structure will be described with reference to FIG. A source line driver circuit 601 and a pixel portion are formed. 6, one pixel in the pixel area 602 is shown.

[0236] The element substrate 610 may be made of glass, quartz, organic resin, metal, alloy, semiconductor, or the like. FRP (Fiber Reinforced Plastics), PVF (Polyvinyl It is made using a plastic substrate made of materials such as fluoride, polyester, or acrylic. That's good.

[0237] The structure of the transistors used in the pixels and the driver circuits is not particularly limited. The transistor may be a top-type transistor or a staggered type transistor. The transistor may be a gate type transistor or a bottom gate type transistor. The semiconductor material is not particularly limited, and examples thereof include silicon, germanium, silicon carbide, and nitride. Gallium, etc., can be used. Alternatively, indium, such as In-Ga-Zn based metal oxides, Alternatively, an oxide semiconductor containing at least one of tungsten, gallium, and zinc may be used.

[0238] The crystallinity of the semiconductor material used in the transistor is not particularly limited. A semiconductor having crystallinity (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a partially crystalline region If a semiconductor having crystallinity is used, the transistor This is preferable because it can suppress deterioration of the star characteristics.

[0239] Here, in addition to the transistors provided in the pixels and the driver circuits, It is preferable to use an oxide semiconductor for a semiconductor device such as a transistor. In particular, it is preferable to use an oxide semiconductor having a wider band gap than silicon. By using an oxide semiconductor with a wider band gap than silicon, the off-state of the transistor can be improved. This allows the current in the MOSFET's low-voltage state to be reduced.

[0240] The oxide semiconductor preferably contains at least indium (In) or zinc (Zn). In-M-Zn oxides (where M is Al, Ti, Ga, Ge, Y, Zr, Sn, It is preferable that the oxide semiconductor contains an oxide represented by the formula (1) of La, Ce or Hf. This is more preferable.

[0241] Here, an oxide semiconductor that can be used in one embodiment of the present invention will be described. .

[0242] Oxide semiconductors are classified into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. As a non-single crystal oxide semiconductor, for example, CAAC-OS (c-axis axially aligned oxide semiconductor) gned crystalline oxide semiconductor), polycrystalline Nanocrystalline oxide semiconductor, nc-OS iconductor), pseudo-amorphous oxide semiconductor (a-like OS:amorph amorphous-like oxide semiconductor, and amorphous oxide semiconductor Conductors, etc.

[0243] CAAC-OS has a c-axis orientation and multiple nanocrystals are connected in the ab-plane direction. The crystal structure has distortion. The distortion is caused by the area where multiple nanocrystals are connected. In the region, between a region with a uniform lattice arrangement and another region with a uniform lattice arrangement, Indicates the point where the direction is changing.

[0244] Nanocrystals are basically hexagonal, but are not limited to regular hexagons and may be non-regular hexagons. In addition, the distortion may have a lattice arrangement such as a pentagon or a heptagon. In addition, in the CAAC-OS, clear grain boundaries (grain boundaries) are not observed even in the vicinity of the strain. It is difficult to confirm the presence of the crystal grains due to the distortion of the lattice arrangement. This is because the CAAC-OS has a lattice structure in the ab-plane direction. The oxygen atoms are not densely packed, and the bond distance between atoms is shortened by the substitution of metal elements. This is because the distortion can be tolerated by changing the frequency band.

[0245] In addition, the CAAC-OS has a layer containing indium and oxygen (hereinafter, the In layer) and an element A layered crystal structure in which layers containing M, zinc, and oxygen (hereinafter referred to as the (M,Zn) layer) are stacked. Indium and element M tend to have a layered structure. It is possible, and when the element M in the (M,Zn) layer is replaced with indium, (In,M,Zn) Also, when the indium in the In layer is replaced with element M, (In,M ) layer.

[0246] CAAC-OS is a highly crystalline oxide semiconductor. Since it is difficult to confirm the grain boundaries, the decrease in electron mobility caused by the grain boundaries is unlikely to occur. In addition, the crystallinity of oxide semiconductors is degraded by the inclusion of impurities and the generation of defects. Therefore, CAAC-OS is designed to prevent impurities and defects (oxygen vacancies (V O :oxygen Therefore, CAA The physical properties of oxide semiconductors containing C-OS are stable. The oxide semiconductor has high heat resistance and high reliability.

[0247] The nc-OS is a nano-sized area (e.g., an area of ​​1 nm to 10 nm, especially 1 nm to 3 nm). The atomic arrangement of nc-OS has periodicity in the nanometer range. There is no regularity in the crystal orientation between the crystals. Therefore, no orientation is observed throughout the film. Therefore, depending on the analysis method, nc-OS may be considered to be a-like OS or amorphous oxide semiconductor. It may be indistinguishable from the above.

[0248] Note that indium, gallium, and zinc are used as a type of oxide semiconductor. In the case of IGZO, the nanocrystals mentioned above make it stable. In particular, IGZO tends to have difficulty growing crystals in air. , small crystals (e.g., For example, the nanocrystals mentioned above may be structurally more stable.

[0249] The a-like OS is an oxide semiconductor that has a structure between the nc-OS and the amorphous oxide semiconductor. Conductive. A-like OS has voids or low density regions. The ke-OS has a lower crystallinity than the nc-OS and CAAC-OS.

[0250] Oxide semiconductors have a variety of structures, each of which has different characteristics. Oxide semiconductors include amorphous oxide semiconductors, polycrystalline oxide semiconductors, a-like OS, and nc The compound may have two or more of -OS, CAAC-OS, and CAAC-OS.

[0251] In addition to the oxide semiconductors mentioned above, Cloud-Aligned Computing (CAC) osite)-OS may also be used.

[0252] CAC-OS is a material that has a conductive function in some parts and an insulating function in other parts. The material as a whole functions as a semiconductor. When used in the active layer, the conductive function is to allow the electrons (or holes) that serve as carriers to flow. The insulating function is to prevent the flow of electrons, which act as carriers. The function of switching (O On / Off function) can be added to CAC-OS. By separating their functions, the functions of both can be maximized.

[0253] The CAC-OS also has a conductive region and an insulating region. The insulating region has the above-mentioned insulating function. In some cases, the conductive and insulating regions are separated at the nanoparticle level. The conductive regions and the insulating regions may be unevenly distributed in the material. may be observed as a cloud-like formation with the edges blurred.

[0254] In addition, in CAC-OS, the conductive region and the insulating region are each 0.5 nm or more. When the particles are dispersed in the material with a size of 10 nm or less, preferably 0.5 nm to 3 nm, There is a match.

[0255] In addition, the CAC-OS is composed of components having different band gaps. For example, CAC-OS consists of a wide gap component originating from the insulating region and a conductive component originating from the conductive region. In this configuration, the carrier is When the carriers flow, the carriers mainly flow in the narrow gap component. The component with the gap acts complementary to the component with the wide gap to form a narrow gap. Carriers also flow into the component with a wide gap in conjunction with the component with a gap. When the CAC-OS is used in a channel forming region of a transistor, In the on-state, a high current drive capability, i.e., a large on-current, and a high field-effect mobility are obtained. It is possible.

[0256] That is, CAC-OS is a matrix composite. or metal matrix composite It can also be called.

[0257] By using the above-mentioned oxide semiconductor material for the semiconductor layer, the fluctuation of electrical characteristics is suppressed and reliability is improved. This makes it possible to realize highly reliable transistors.

[0258] In addition, the transistor having the above-described semiconductor layer can be used as a transistor due to its low off-state current. It is possible to hold the charge stored in the capacitor for a long period of time through such a transistor. By applying a transistor to each pixel, the gradation of the image displayed in each display area can be maintained while driving It is also possible to shut down the circuit. As a result, electronic devices with extremely low power consumption can be realized. It can be realized.

[0259] In order to stabilize the characteristics of the transistor, it is preferable to provide an undercoat film. Inorganic films such as silicon oxide film, silicon nitride film, silicon oxynitride film, and silicon nitride oxide film The insulating film can be formed in a single layer or a multilayer structure. CVD (Chemical Vapor Deposition) method (Plasma CVD method , thermal CVD method, MOCVD (Metal Organic CVD) method, etc.), ALD ( Formed using Atomic Layer Deposition (ALD), coating, printing, etc. It should be noted that the undercoat film does not have to be provided if it is not necessary.

[0260] The FET 623 indicates one of the transistors formed in the driver circuit section 601. The driving circuits are made up of various CMOS circuits, PMOS circuits, or NMOS circuits. In this embodiment, a driver integrated type in which a driver circuit is formed on a substrate is shown. However, this is not necessarily required, and the drive circuit can be formed externally instead of on the substrate. .

[0261] The pixel section 602 includes a switching FET 611, a current control FET 612 and its driver. The pixel is formed of a plurality of pixels including an anode 613 electrically connected to the drain. However, the present invention is not limited to this, and the pixel section may be formed by combining three or more FETs and a capacitive element.

[0262] An insulator 614 is formed to cover the end of the anode 613. It can be formed by using a photosensitive acrylic.

[0263] In order to improve the coverage of the EL layer and the like to be formed later, the upper end of the insulator 614 is For example, the material of the insulator 614 is When a positive photosensitive acrylic is used, the radius of curvature (0. It is preferable that the insulating material 614 has a curved surface having a thickness of 2 μm to 3 μm. Either a negative-type photosensitive resin or a positive-type photosensitive resin can be used.

[0264] An EL layer 616 and a cathode 617 are formed on the anode 613. It is preferable to use a material having a large work function for the anode 613. For example, ITO film, or silicon-containing indium tin oxide film, 2 to 20 wt% oxide Indium oxide film containing zinc, titanium nitride film, chromium film, tungsten film, Zn film, Pt In addition to single-layer films such as titanium nitride films, laminated films of titanium nitride and aluminum-based films, A three-layer structure of a titanium nitride film, a film mainly composed of aluminum, and a titanium nitride film can be used. In addition, the multilayer structure has low wiring resistance and good ohmic contact. It can also function as an anode.

[0265] The EL layer 616 is formed by deposition using a deposition mask, inkjet printing, or spin coating. The EL layer 616 is formed by the structure described in the first embodiment. Other materials constituting the EL layer 616 include low molecular weight compounds, may be a polymer compound (including an oligomer or a dendrimer).

[0266] Furthermore, the material used for the cathode 617 formed on the EL layer 616 is a material having a small work function. Materials that are suitable for use in the manufacture of semiconductors include Al, Mg, Li, Ca, and their alloys and compounds (MgAg, MgIn, It is preferable to use AlLi, etc. In the case of transmitting light, the cathode 617 is made of a thin metal film and a transparent conductive film (I TO, indium oxide containing 2-20wt% zinc oxide, indium tin containing silicon It is preferable to use a laminate of a metal oxide such as zinc oxide (ZnO).

[0267] The anode 613, the EL layer 616, and the cathode 617 form a light-emitting device. .

[0268] Furthermore, the sealing substrate 604 is bonded to the element substrate 610 with a sealant 605. A light emitting device is placed in a space 607 surrounded by a child substrate 610, a sealing substrate 604, and a sealant 605. The structure is provided with a chair 618. The space 607 is filled with a filling material. In some cases, the gas is filled with an inert gas (nitrogen, argon, etc.), and in other cases, it is filled with a sealing material. By forming a recess in the sealing substrate and providing a desiccant there, deterioration caused by moisture can be prevented. This is a preferable configuration because it is possible to suppress the degradation.

[0269] It is preferable to use epoxy resin or glass frit for the sealing material 605. It is desirable that these materials are as impermeable to moisture and oxygen as possible. Materials used for the sealing substrate 604 include glass substrates, quartz substrates, and FRP (Fiber Reinforced Plastics). reinforced plastics), PVF (polyvinyl fluoride), polyester A plastic substrate made of, for example, polyester or acrylic can be used.

[0270] Although not shown in FIG. 7, a protective film may be provided on the cathode. The protective film may be an organic resin film or an inorganic A protective film may be formed so as to cover the exposed portion of the sealant 605. The protective film may be formed on the front and side surfaces of the pair of substrates, the sealing layer, the insulating layer, It can be provided to cover the exposed sides of the above.

[0271] The protective film can be made of a material that is difficult for impurities such as water to permeate. It is possible to effectively suppress the diffusion of impurities such as those mentioned above from the outside to the inside.

[0272] The materials that make up the protective film include oxides, nitrides, fluorides, sulfides, ternary compounds, and metals. Alternatively, polymers and the like can be used, for example, aluminum oxide, hafnium oxide, hafnium oxide, etc. Funium silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide , titanium oxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide , cerium oxide, scandium oxide, erbium oxide, vanadium oxide or indium oxide Materials containing uranium, aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride, titanium nitride, niobium nitride, molybdenum nitride, zirconium nitride, or gallium nitride, etc. Materials, nitrides containing titanium and aluminum, oxides containing titanium and aluminum , oxides containing aluminum and zinc, sulfides containing manganese and zinc, cerium and and sulfides containing strontium, oxides containing erbium and aluminum, yttrium Materials including, for example, oxides containing lithium and zirconium can be used.

[0273] The protective film should be formed using a film formation method that provides good step coverage. One such technique is atomic layer deposition (ALD). The ALD method can be used to form a protective It is preferable to use the ALD method for films that are dense and free of cracks and pinholes. It is possible to form a protective film having reduced defects or a uniform thickness. Damage to the processed member when forming the protective film can be reduced.

[0274] For example, by forming a protective film using the ALD method, it is possible to fabricate a surface with complex unevenness or a touch panel. It is possible to form a uniform protective film with few defects on the top, sides and back of the panel. .

[0275] Since the light emitting device in this embodiment uses the light emitting device described in Embodiment 1, A display device having excellent characteristics can be obtained. Since the device is a light-emitting device with a long life, it can be a display device with good reliability. In addition, since the display device using the light-emitting device described in embodiment 1 has high light emission efficiency, it consumes less power. It is possible to make a light emitting device with a small size.

[0276] In FIG. 8, a light-emitting device that emits blue light is formed, and a color conversion layer is provided to produce a full color image. FIG. 8(A) shows a substrate 1001, a base insulating film 1002, a gate insulating film 1003, and a light emitting device. The gate insulating film 1003, the gate electrodes 1006, 1007, 1008, the first interlayer insulating film 10 20, the second interlayer insulating film 1021, the peripheral portion 1042, the pixel portion 1040, and the driving circuit portion 104 1, first electrodes 1024R, 1024G, 1024B of the light-emitting device, partition walls 1025, E L layer 1028, cathode 1029 of the light emitting device, sealing substrate 1031, sealant 1032, etc. is illustrated.

[0277] In addition, in FIG. 8(A), the color conversion layers (red color conversion layer 1034R, green color conversion layer 1034G ) is provided on a transparent substrate 1033. A black matrix 1035 is further provided. The transparent substrate 1033 on which the color conversion layer and the black matrix are provided is aligned. The color conversion layer and the black matrix 1035 are fixed to the substrate 1001. It may be covered with an overcoat layer 1036 .

[0278] In FIG. 8B, the color conversion layers (red color conversion layer 1034R and green color conversion layer 1034G) are In the example shown, the insulating film 1003 is formed between the first interlayer insulating film 1020. In addition, the colored layer may be provided between the substrate 1001 and the sealing substrate 1031 .

[0279] In the light emitting device described above, the light is taken in toward the substrate 1001 on which the FET is formed. The light emitting device has a bottom emission structure, but the light is taken in from the sealing substrate 1031 side. The light emitting device may have a structure in which the light is emitted from the top (top emission type). A cross-sectional view of a light-emitting device is shown in FIG. 9. In this case, a substrate 1001 that does not transmit light is used. The bottom is not connected to the FET and the anode of the light-emitting device until the connection electrode is fabricated. The third interlayer insulating film 1037 is then formed in the same manner as in the case of the m-emission type light emitting device. The insulating film is formed to cover the electrode 1022. This insulating film may also serve as a planarizing film. The interlayer insulating film 1037 may be formed using the same material as the second interlayer insulating film, or other known materials. It is possible.

[0280] The first electrodes 1024R, 1024G, and 1024B of the light-emitting device are herein referred to as anodes. In addition, the top emission type light emitting device shown in FIG. In this case, it is preferable that the first electrode is a reflective electrode. The device structure is designed to produce light.

[0281] In the top emission structure shown in Fig. 9, the color conversion layer (red color conversion layer 1034R, green The sealing can be performed by using a sealing substrate 1031 provided with a color conversion layer 1034G. A black matrix 1035 may be provided between the pixels in the pixel region 1031. Color conversion layers (red color conversion layer 1034R, green color conversion layer 1034G) and black matrix The encapsulation substrate 1031 may be covered with an overcoat layer. A substrate having optical properties is used. In addition, the color conversion layer (red color conversion layer 1034R, green The color conversion layer 1034G) is formed on the cathode 1029 (or on a protective film provided on the cathode 1029). It may be provided directly on the

[0282] The insulating layer 1038 acts as a protective layer to prevent impurities from diffusing into the light-emitting device. The insulating layer 1038 may be an oxide, a nitride, a fluoride, a sulfide, a ternary compound, a metal, or Polymers and the like can be used. For example, aluminum oxide, hafnium oxide, hafnium lanthanum silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide, acid Titanium oxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide, oxide Cerium oxide, scandium oxide, erbium oxide, vanadium oxide or indium oxide Materials containing aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride, titanium nitride, etc. Materials containing tungsten, niobium nitride, molybdenum nitride, zirconium nitride, or gallium nitride, etc. , nitrides containing titanium and aluminum, oxides containing titanium and aluminum, Oxides containing aluminum and zinc, sulfides containing manganese and zinc, cerium and Sulfides containing strontium, oxides containing erbium and aluminum, yttrium Materials including oxides containing titanium and zirconium can be used. Silicon nitride, silicon oxide, etc. Silicon, silicon nitride oxide, etc. are preferable. Note that the insulating layer 1038 is not necessarily formed.

[0283] The space 1030 may be filled with a resin. The resin has a refractive index of 1.4 to 2.0. It is preferable that the resin has a refractive index of 1.7 to 1.9. The presence of a layer with a relatively high refractive index between the transparent electrode and the color conversion layer allows for the thin-film mode of light This reduces losses and provides a more efficient light-emitting device.

[0284] In the above configuration, even if the EL layer has a plurality of light-emitting layers, a single light-emitting For example, the above-mentioned tandem light-emitting device may be combined with the above-mentioned structure. In addition, multiple EL layers are provided in one light-emitting device with a charge generating layer sandwiched between them, and each EL The layer may be formed with one or more light-emitting layers.

[0285] In a top emission type light emitting device, a microcavity structure can be suitably applied. Light-emitting devices with a microcavity structure use an anode as a reflective electrode and a cathode as a semi-transparent / semi-reflective electrode. The reflective electrode and the semi-transmissive / semi-reflective electrode are separated by at least The device has an EL layer, and at least has a light-emitting layer which serves as a light-emitting region.

[0286] The reflectance of the reflective electrode for visible light is 40% to 100%, preferably 70% to 100%. %, and its resistivity is 1×10 -2 The film is assumed to be less than Ωcm. The semi-reflective electrode has a visible light reflectance of 20% to 80%, preferably 40% to 70%. , and its resistivity is 1×10 -2 It is assumed that the film has a resistance of less than Ωcm.

[0287] The light emitted from the light-emitting layer included in the EL layer is reflected by the reflective electrode and the semi-transparent and semi-reflective electrode. The light is reflected and resonates.

[0288] The light-emitting device is configured by changing the thickness of the transparent conductive film, the composite material, the carrier transport material, etc. By adjusting the thickness of the reflective electrode, the optical distance between the reflective electrode and the semi-transmissive and semi-reflective electrode can be changed. This strengthens the light of the resonating wavelength between the reflective electrode and the semi-transparent and semi-reflective electrode, and resonates. It can attenuate light of wavelengths that are not

[0289] The light reflected by the reflective electrode and returned (first reflected light) is semi-transmitted from the light emitting layer. The light that is directly incident on the semi-reflective electrode (first incident light) interferes greatly with the reflective electrode. The optical path length of the light-emitting layer is (2n-1)λ / 4 (where n is a natural number greater than or equal to 1, and λ is the amplified It is preferable to adjust the optical distance to a wavelength that is suitable for the first emission. By matching the phase of the reflected light with that of the first incident light, the light emitted from the light-emitting layer can be amplified. do.

[0290] In the above configuration, even if the EL layer has a plurality of light-emitting layers, a single light-emitting For example, the above-mentioned tandem light-emitting device may be combined with the above-mentioned structure. In addition, multiple EL layers are provided in one light-emitting device with a charge generating layer sandwiched between them, and each EL The layer may be formed with one or more light-emitting layers.

[0291] (Embodiment 4) In this embodiment, examples of electronic devices each including a light-emitting device according to one embodiment of the present invention will be described. The light-emitting device according to one embodiment of the present invention has low power consumption and high reliability. As a result, the electronic device described in this embodiment has low power consumption and high reliability. It is possible to make it into a device.

[0292] As an example of an electronic device to which the light-emitting device is applied, a television set (television, (also called television receivers), computer monitors, digital cameras, digital digital video cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices) (hereinafter referred to as "computer games"), portable game machines, personal digital assistants, audio playback devices, large game machines such as pachinko machines Specific examples of these electronic devices are shown below.

[0293] FIG. 10A shows an example of a television device. The television device has a housing 71. A display unit 7103 is built into the display unit 7101. The display unit 7103 can display images. The display unit 7103 is configured by arranging light-emitting devices in a matrix. .

[0294] The television device can be operated using an operation switch provided on the housing 7101 or a separate remote control. The remote control device 7110 includes an operation key 7109. This allows you to control the channel and volume, and the image displayed on the display unit 7103 In addition, the remote control operation device 7110 can be operated. A display portion 7107 for displaying information output from the image forming apparatus may be provided.

[0295] The television set is assumed to be equipped with a receiver and a modem. It can receive television broadcasts and can also communicate by wire or wirelessly via a modem. By connecting to a network, communication can be one-way (sender to receiver) or two-way (sender to It is also possible to communicate information between the sender and the recipient, or between the recipients themselves.

[0296] FIG. 10B1 shows a computer, which includes a main body 7201, a housing 7202, a display unit 7203, Including a keyboard 7204, an external connection port 7205, a pointing device 7206, etc. In addition, this computer has a display unit 7203 in which light emitting devices are arranged in a matrix. The computer shown in FIG. 10(B1) is manufactured by using the computer shown in FIG. 10(B2). The computer in FIG. 10B2 has a keyboard 7204, a pointer, A second display unit 7210 is provided instead of the display device 7206. The display unit 7210 is a touch panel type, and the input displayed on the second display unit 7210 Input can be made by operating the display for the keyboard with a finger or a special pen. The display unit 7210 is capable of displaying not only input images but also other images. The display unit 7203 may also be a touch panel. Two screens are connected by a hinge. This can cause problems such as scratching or breaking the screen when storing or transporting the device. This can also be prevented.

[0297] FIG. 10C shows an example of a mobile terminal. The mobile phone is built in a housing 7401. In addition to the display unit 7402, the operation buttons 7403, the external connection port 7404, the speaker 74 05, a microphone 7406, etc. The display unit 7402 is made using an optical device.

[0298] The mobile terminal shown in FIG. 10C allows users to input information by touching the display portion 7402 with a finger or the like. In this case, the user can make a call or create an email. Such an operation can be performed by touching the display portion 7402 with a finger or the like.

[0299] The screen of the display unit 7402 has three main modes. The first is a display mode that is mainly used for displaying images. The first mode is a display mode, the second is an input mode for inputting information such as characters, and the third mode is a display mode. This is a display + input mode that combines the display mode and the input mode.

[0300] For example, when making a call or composing an e-mail, the display unit 7402 is used to input characters. The main character input mode is to input characters displayed on the screen. It is preferable to display a keyboard or number buttons on most of the screen of the display portion 7402. I wish.

[0301] In addition, the mobile terminal may include a sensor for detecting the inclination, such as a gyro or an acceleration sensor. By providing a device, the orientation of the mobile terminal (vertical or horizontal) can be determined and the screen display of the display portion 7402 can be displayed. The display can be switched automatically.

[0302] The screen mode can be changed by touching the display portion 7402 or by operating the housing 7401. This is done by operating the button 7403. Also, depending on the type of image displayed on the display unit 7402, For example, the image signal to be displayed on the display unit is a moving image. If it is data, the mode is switched to display mode, and if it is text data, the mode is switched to input mode.

[0303] In the input mode, the optical sensor of the display unit 7402 detects a signal and displays If there is no input by touch operation of the part 7402 for a certain period of time, the screen mode is changed to the input mode. Alternatively, the display mode may be switched from the normal mode to the display mode.

[0304] The display portion 7402 can also function as an image sensor. By touching the palm or fingers of the user on the sensor 02 and capturing an image of the palm print or fingerprint, the user can be authenticated. In addition, a backlight that emits near-infrared light to the display unit or a sensing light that emits near-infrared light By using a source, it is also possible to image finger veins, palm veins, etc.

[0305] Note that the configuration shown in this embodiment mode is a combination of the configurations shown in Embodiment Modes 1 to 3. They can be used in combination.

[0306] As described above, the light-emitting device according to one embodiment of the present invention has a very wide range of application. The light-emitting device according to one embodiment of the present invention can be applied to electronic devices in various fields. It is possible to obtain an electronic device with lower power consumption.

[0307] FIG. 11(A) is a schematic diagram showing an example of a cleaning robot.

[0308] The cleaning robot 5100 has a display 5101 arranged on the top surface and multiple The camera 5102, the brush 5103, and the operation button 5104 are also shown. However, the underside of the cleaning robot 5100 is provided with tires, a suction port, etc. The robot 5100 also has an infrared sensor, an ultrasonic sensor, an acceleration sensor, a piezo sensor, It is equipped with various sensors such as a sensor, a light sensor, and a gyro sensor. 100 is equipped with wireless communication means.

[0309] The cleaning robot 5100 moves by itself, detects dirt 5120, and sucks it out from the suction port on its bottom. It can suck up dirt.

[0310] In addition, the cleaning robot 5100 analyzes the image captured by the camera 5102 and detects walls, furniture, or It can detect obstacles such as steps. It can also detect wiring and other obstacles by image analysis. If an object that is likely to get tangled in the brush 5103 is detected, the rotation of the brush 5103 can be stopped. can.

[0311] The display 5101 can display the remaining battery level, the amount of dirt sucked up, etc. The route traveled by the cleaning robot 5100 can be displayed on the display 5101. In addition, the display 5101 may be a touch panel, and the operation buttons 5104 may be a display. It may be provided in the ray 5101.

[0312] The cleaning robot 5100 can communicate with a portable electronic device 5140 such as a smartphone. The images captured by the camera 5102 can be displayed on the portable electronic device 5140. Therefore, the owner of the Cleaning Robot 5100 can check the state of the room even when he / she is away from home. In addition, the display on the display 5101 can be displayed on a mobile electronic device such as a smartphone. You can also check it out at.

[0313] The light-emitting device according to one embodiment of the present invention can be used for the display 5101 .

[0314] The robot 2100 shown in FIG. 11(B) includes a computing device 2110, an illuminance sensor 2101, A microphone 2102, an upper camera 2103, a speaker 2104, a display 2105, It is equipped with a lower camera 2106, an obstacle sensor 2107, and a movement mechanism 2108.

[0315] The microphone 2102 has a function of detecting the user's voice and environmental sounds. The speaker 2104 has a function of emitting sound. The user can communicate with the computer using the computer 2102 and the speaker 2104. It is possible.

[0316] The display 2105 has a function of displaying various information. It is possible for the user to display desired information on the display 2105. The display 2105 may be equipped with a touch panel. The information terminal may be a terminal that can be used for charging and discharging the battery. and enables data transfer.

[0317] The upper camera 2103 and the lower camera 2106 are used to capture images of the surroundings of the robot 2100. The obstacle sensor 2107 detects the obstacles of the robot 210 using the moving mechanism 2108. When the robot 21 moves forward, it can sense the presence or absence of obstacles in its path. 00 uses an upper camera 2103, a lower camera 2106, and an obstacle sensor 2107. The light-emitting device according to one embodiment of the present invention can recognize the surrounding environment and move safely. It can be used for the display 2105.

[0318] FIG. 11C is a diagram showing an example of a goggle-type display. Goggle-type display For example, the device includes a housing 5000, a display unit 5001, a speaker 5003, and an LED lamp 5004. , connection terminal 5006, sensor 5007 (force, displacement, position, speed, acceleration, angular velocity, rotation speed ,distance, light, liquid, magnetic, temperature, chemical, sound, time, hardness, electric field, current, voltage, power, (including functions to measure radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), The microphone 5008, the display unit 5002, the support unit 5012, the earphones 5013, etc. .

[0319] The light-emitting device according to one embodiment of the present invention can be used for the display portion 5001 and the display portion 5002. .

[0320] The light-emitting device according to one embodiment of the present invention can be mounted on the windshield or dashboard of an automobile. FIG. 12 shows a light-emitting device according to one embodiment of the present invention, which is mounted on a windshield or a dashboard of an automobile. Display areas 5200 to 5203 show an embodiment of the present invention. The display is provided using a light-emitting device.

[0321] The display area 5200 and the display area 5201 are provided on the windshield of an automobile. The light-emitting device is a display device equipped with the light-emitting device of the embodiment. By using electrodes that can be connected to each other, the other side can be seen through, making it a so-called see-through display. If the display is see-through, it can be installed on the windshield of a car. Even if the device is placed in a place where it is not obstructing the view, When transistors are provided, organic transistors made of organic semiconductor materials or oxides are used. A light-transmitting transistor, such as a transistor using a semiconductor, is preferably used.

[0322] A display region 5202 is a display device provided with a light-emitting device according to one embodiment of the present invention provided in a pillar portion. The display area 5202 can display an image captured by an imaging means provided on the vehicle body. This can compensate for the visibility obstructed by the pillars. The display area 5203 provided in the door portion is set outside the car to display the view blocked by the car body. By projecting images from a fixed imaging device, blind spots can be filled and safety can be improved. By projecting an image that complements the invisible parts, it is possible to create a more natural and unnatural appearance. Safety checks can be carried out quickly.

[0323] The display area 5203 also provides navigation information, speed, RPM, and various other information. The display items and layout can be changed as needed to suit the user's preferences. This information can also be set in the display areas 5200 to 5202. In addition, the display areas 5200 to 5203 can be used as lighting devices. It is also possible.

[0324] 13(A) and (B) show a foldable mobile information terminal 5150. The foldable mobile information terminal 5150 includes a housing 5151, a display area 5152, and a bending portion 515. 13(A) shows the portable information terminal 5150 in an unfolded state. Fig. 5B) shows the portable information terminal in a folded state. The portable information terminal 5150 has a large display area. Despite having a range of 5152, it folds up compactly and is highly portable.

[0325] The display area 5152 can be folded in half by the bend 5153. 3 is composed of an expandable member and multiple support members, and when folding, the expandable The bent portion 5153 has a radius of curvature of 2 mm or more, preferably 3 mm or more. It can be folded.

[0326] The display area 5152 is a touch panel (input / output) equipped with a touch sensor (input device). The light-emitting device according to one embodiment of the present invention can be used in the display region 5152. Cut.

[0327] 14(A) to (C) show a foldable portable information terminal 9310. FIG. 14(A) shows a portable information terminal 9310 in an unfolded state. FIG. 14(B) shows a portable information terminal 9310 in an unfolded state or A portable information terminal 9310 is shown in a folded state changing from one to the other. FIG. 14C shows the portable information terminal 9310 in a folded state. The foldable design is highly portable and unfolds for a seamless, large viewing area. This provides excellent visibility of the display.

[0328] The display panel 9311 is supported by three housings 9315 connected by hinges 9313. The display panel 9311 is a touch panel equipped with a touch sensor (input device). The display panel 9311 may be a display panel (input / output device). The portable information terminal 9310 is in an unfolded state by bending the two housings 9315. The light-emitting device according to one embodiment of the present invention can be reversibly transformed from a folded state to a folded state. It can be used for the display panel 9311. EXAMPLES

[0329] <Synthesis example> This example describes a synthesis method of the low refractive index hole transport material described in Embodiment 2. do.

[0330] First, N,N-bis(4-cyclohexylphenyl)-9,9-dimethyl-9H-fluoro The detailed synthesis method of oren-2-amine (abbreviation: dchPAF) is explained. The structure of PAF is shown below.

[0331] [ka]

[0332] <Step 1: N,N-bis(4-cyclohexylphenyl)-9,9,-dimethyl-9 Synthesis of H-fluorene-2-amine (abbreviation: dchPAF) Add 10.6 g (51 mm) of 9,9-dimethyl-9H-fluoren-2-amine to a three-neck flask. ol), 4-cyclohexyl-1-bromobenzene 18.2g (76mmol), sodium Add 21.9 g (228 mmol) of t-butoxide and 255 mL of xylene. After degassing under reduced pressure, the atmosphere in the flask was replaced with nitrogen. The mixture was heated and stirred. Here, allyl palladium chloride dimer (II) (abbreviation: [(Allyl) PdCl]2) 370 mg (1.0 mmol), di-tert-butyl(1-methyl-2 ,2-Diphenylcyclopropyl)phosphine (abbreviation: cBRIDP (registered trademark)) 16 60 mg (4.0 mmol) was added and the mixture was heated at 120° C. for about 5 hours. After that, the temperature of the flask was returned to about 60°C, and about 4 mL of water was added to precipitate a solid. The resulting solid was filtered off. The filtrate was concentrated, and the resulting solution was purified by silica gel column chromatography. The resulting solution was concentrated to obtain a concentrated toluene solution. The precipitate was filtered at about 10°C, and the resulting solid was heated to about 80°C. The product was dried under reduced pressure to give 10.1 g of a white solid in 40% yield. The synthesis scheme of dchPAF is shown below.

[0333] [ka]

[0334] The white solid obtained in step 1 was analyzed by nuclear magnetic resonance spectroscopy ( 1 H-NMR The analysis results are shown below. From this, it was confirmed that dchPAF was successfully synthesized in this synthesis example. Understood.

[0335] 1 H-NMR.δ(CDCl3):7.60(d,1H,J=7.5Hz),7.53( d,1H,J=8.0Hz),7.37(d,2H,J=7.5Hz),7.29(td ,1H,J=7.5Hz,1.0Hz),7.23(td,1H,J=7.5Hz,1. 0Hz),7.19(d,1H,J=1.5Hz),7.06(m,8H),6.97( dd,1H,J=8.0Hz,1.5Hz),2.41-2.51(brm,2H),1 .79-1.95(m,8H),1.70-1.77(m,2H),1.33-1.45 (brm,14H), 1.19-1.30(brm,2H).

[0336] Similarly, organic compounds represented by the following structural formulas (101) to (111) were synthesized.

[0337] [ka]

[0338] [ka]

[0339] Nuclear magnetic resonance spectroscopy of the above organic compounds ( 1 The results of the analysis by H-NMR are shown below.

[0340] Structural formula (101) N-[(4'-cyclohexyl)-1,1'-biphenyl-4-yl]- N-(4-cyclohexylphenyl)-9,9-dimethyl-9H-fluorene-2-amine (Abbreviation: chBichPAF) 1 H-NMR.δ(CDCl3):7.63(d,1H,J=7.5Hz),7.57( d,1H,J=7.5Hz),7.51(d,2H,J=8.0Hz),7.46(d, 2H,J=7.5Hz),7.38(d,1H,J=7.5Hz),7.30(td,1 H,J=7.0Hz,1.5Hz),7.20-7.28(m,6H),7.01-7. 18(m,7H),2.43-2.57(brm,2H),1.81-1.96(m,8 H),1.71-1.79(brm,2H),1.34-1.50(brm,14H), 1.20-1.32(brm,2H).

[0341] Structural formula (102) N,N-bis(4-cyclohexylphenyl)-N-(spiro[cyclo Hexane-1,9'[9H]fluoren]-2'-yl)amine (abbreviation: dchPASc hF) 1 H-NMR.δ(CDCl3):7.60-7.65(m,2H),7.54(d,1 H,J=8.0Hz),7.28-7.35(m,2H),7.19-7.24(t,1 H,J=7.5Hz),7.02-7.12(m,8H),6.97-7.22(d,1 H,J=8.0Hz),2.40-2.52(brm,2H),1.79-1.95(m ,10H),1.63-1.78(m,9H),1.55-1.63(m,1H),1. 32-1.46(m,8H),1.18-1.30(brm,2H).

[0342] Structural formula (103) N-[(4'-cyclohexyl)-1,1'-biphenyl-4-yl] -N-(4-cyclohexylphenyl)-N-(spiro[cyclohexane-1,9'-[ 9H]-Fluoren]-2'-yl)-amine (abbreviation: chBichPASchF) 1 H-NMR.δ(CDCl3):7.65(d,2H,J=8.0Hz),7.58( d,1H,J=8.0Hz),7.51(d,2H,J=8.5Hz),7.46(m, 2H),7.39(d,1H,1.5Hz),7.32(t,1H,J=8.0Hz), 7.21-7.38(m,3H),7.14-7.18(m,2H),7.08-7.1 4(m,4H),7.06(dd,1H,J=8.0Hz,1.5Hz),2.43-2 .57(brm,2H),1.80-1.97(m,10H),1.64-1.80(m ,9H),1.56-1.64(m,1H),1.34-1.53(m,8H),1.2 0-1.32(brm,2H).

[0343] Structural formula (104) N-(4-cyclohexylphenyl)-N,N-bis(spiro[cyclo Hexane-1,9'-[9H]-fluoren]-2'-yl)amine (abbreviation: SchFB 1chP) 1 H-NMR.δ(CDCl3):7.64(t,4H,J=8.0Hz),7.59( d,2H,J=8.5Hz),7.39(brs,2H),7.33(t,2H,J=7 .5Hz),7.20-7.25(m,2H),7.12(brs,4H),7.08( d,2H,J=8.0Hz),2.44-2.52(brm,1H),1.63-1.9 7(m,23H),1.50-1.61(m,2H),1.34-1.48(m,4H) ,1.20-1.32(brm,1H).

[0344] Structural formula (105) N-[(3',5'-ditertiarybutyl)-1,1'-biphenyl] -4-yl]-N-(4-cyclohexylphenyl)-9,9-dimethyl-9H-fluoro Len-2-amine (abbreviation: mmtBuBichPAF) 1 H-NMR.δ(CDCl3):7.63(d,1H,J=7.5Hz),7.57( d,1H,J=8.0Hz),7.44-7.49(m,2H),7.37-7.42( m,4H),7.31(td,1H,J=7.5Hz,2.0Hz),7.23-7.2 7(m,2H),7.15-7.19(m,2H),7.08-7.14(m,4H), 7.05(dd,1H,J=8.0Hz,2.0Hz),2.43-2.53(brm, 1H),1.81-1.96(m,4H),1.75(d,1H,J=12.5Hz), 1.32-1.48(m,28H),1.20-1.31(brm,1H).

[0345] Structural formula (106) N,N-bis(3',5'-ditertiarybutyl-1,1'-biphenyl) nyl-4-yl)-9,9,-dimethyl-9H-fluoren-2-amine (abbreviation: dmm tBuBiAF) 1 H-NMR.δ(CDCl3):7.66(d,1H,J=7.5Hz),7.62( d,1H,J=8.0Hz),7.51(d,4H,J=8.5Hz),7.38-7. 44(m,7H),7.26-7.35(m,3H),7.20-7.25(m,4H) ,7.13(dd,1H,J=8.0Hz,1.5Hz),1.45(s,6H),1. 39(s,36H).

[0346] Structural formula (107) N-(3,5-ditertiary butylphenyl)-N-(3',5', -Di-tertiarybutyl-1,1'-biphenyl-4-yl)-9,9,-dimethyl-9 H-Fluorene-2-amine (abbreviation: mmtBuBimmtBuPAF) 1 H-NMR.δ(CDCl3):7.64(d,1H,J=7.5Hz),7.57( d,1H,J=8.0Hz),7.48(d,2H,J=8.0Hz),7.43(m, 2H),7.39(m,2H),7.31(td,1H,J=6.0Hz,1.5Hz) ,7.15-7.25(m,4H),6.97-7.02(m,4H),1.42(s, 6H), 1.38(s,18H), 1.25(s,18H).

[0347] Structural formula (108) N,N-bis(4-cyclohexylphenyl)-9,9-dipropyl- 9H-Fluoren-2-amine (abbreviation: dchPAPrF) 1 H-NMR.δ(CDCl3):7.58(m,1H),7.51(d,1H,J=8 .0Hz),7.28(t,2H,J=7.5Hz),7.19-7.24(m,1H) ,7.11(d,1H,J=1.5Hz),7.00-7.19(m,8H),6.97 (dd,1H,J=8.0Hz,1.5Hz),2.40-2.50(brm,2H), 1.70-1.94(m,14H),1.33-1.46(m,8H),1.18-1. 30(brm,2H),0.60-0.78(m,10H).

[0348] Structural formula (109) N-[(3',5'-dicyclohexyl)-1,1'-biphenyl-4 -yl]-N-(4-cyclohexylphenyl)-9,9-dimethyl-9H-fluorene -2-Amine (abbreviation: mmchBichPAF) 1H-NMR.δ(CDCl3):7.63(d,1H,J=7.5Hz),7.57( d,1H,J=8.5Hz),7.46(d,2H,J=8.5Hz),7.39(d, 1H,J=7.5Hz),7.31(td,1H,J=7.5Hz,1.5Hz),7. 21-7.28(m,4H),7.07-7.18(m,6H),7.02-7.06( m,1H),7.01(s,1H),2.44-2.57(brm,3H),1.89- 1.96(m,6H),1.81-1.88(m,6H),1.71-1.78(m,3 H),1.34-1.53(m,18H),1.20-1.32(m,3H).

[0349] Structural formula (110) N-(3,3'',5,5''-tetra-t-butyl-1,1':3' ,1''-terphenyl-5'-yl)-N-(4-cyclohexylphenyl)-9,9 -Dimethyl-9H-fluoren-2-amine (abbreviation: mmtBumTPchPAF) 1 H-NMR(300MHz, CDCl3):δ=7.63(d,J=6.6Hz,1H ),7.58(d,J=8.1Hz,1H),7.42-7.37(m,4H),7.3 6-7.09(m,14H),2.55-2.39(m,1H),1.98-1.20( m,51H).

[0350] Structural formula (111) N-(4-cyclododecylphenyl)-N-(4-cyclohexylphenyl) Nyl)-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: CdoPchPAF ) 1 H-NMR(300MHz, CDCl3):δ=7.61(d,J=6.6Hz,1H ),7.53(d,J=8.1Hz,1H),7.37(d,J=7.5Hz,1H), 7.33-7.17(m,3H),7.12-6.95(m,9H),2.77-2.6 6(m,1H),2.52-2.39(m,1H),1.96-1.26(m,37H) .

[0351] In addition, in Figs. 15 to 26, the refractive indexes of the above 12 materials are measured using a spectroscopic ellipsometer (J. The results are shown in Fig. 1. 15 is dchPAF, 16 is chBichPAF, and 17 is dchPASchF. , Figure 18 is chBichPASchF, Figure 19 is SchFB1chP, Figure 20 is mm tBuBichPAF, Figure 21 is dmmtBuBiAF, Figure 22 is mmtBuBim mtBuPAF, Figure 23 is dchPAPrF, Figure 24 is mmchBichPAF, Figure 25 shows the refractive index of mmtBumTPchPAF, and Figure 26 shows the refractive index of CdoPchPAF. The data was obtained by forming a film of each layer of material on a quartz substrate to a thickness of about 50 nm by vacuum deposition. The film used was made of a material that is similar to the ordinary ray, n, which is the refractive index of ordinary light, and the extraordinary ray. The refractive index of light, n, is written as Extra-ordinary.

[0352] Thus, it was found that these organic compounds are materials with low refractive index. EXAMPLES

[0353] In this embodiment, a light-emitting device 1 according to one embodiment of the present invention having a small refractive index of a hole transport layer and a light-emitting device having a normal refractive index are used. Comparison of Efficiency For the light-emitting device 1, the amount of light reaching the color conversion layer was calculated from a simulation. The results are shown below.

[0354] The calculations were performed using an organic device simulator (semiconducting emissiv e thin film optics simulator:setfos;cybernetes The light-emitting region was fixed at the center of the light-emitting layer, and the organic layer was The refractive index is assumed to be 1.6 for low refractive index materials and 1.9 for normal refractive index materials. The wavelength dispersion is The thickness of each layer is determined based on the blue index (B The emission spectrum was as shown in FIG. The light-emitting device is a top-emitting device that extracts light from the cathode side. The total optical path length between the reflecting electrode on the anode side and the cathode is The thickness of the hole transport layer was adjusted so that it was an integer multiple of λ / 2. The calculation was carried out taking into account the quenching due to the Purcell effect. The layer structure of the light emitting device is shown in the table below.

[0355] [Table 1]

[0356] The refractive index and extinction coefficient of Ag, ITSO, and Ag:Mg are based on the physical properties of the materials. Ta.

[0357] Under the above conditions, the amount of light reaching the color conversion layer when the refractive index of the color conversion layer is changed The amount of light reaching the color conversion layer was calculated as follows: The results were calculated from the light extraction efficiency in the EL display and the sum of the guide modes in the color conversion layer. Shown in Figure 28.

[0358] As shown in FIG. 28, by decreasing the refractive index of the hole transport layer, the refractive index of the color conversion layer can be brought within the practical range. It was found that the amount of light reaching the color conversion layer increased in the The increase in β means that more excitation light reaches the color conversion layer, and more QDs are Can be excited.

[0359] (Reference example) In this reference example, a light-emitting device using the low refractive index material described in the embodiment and a light-emitting device not using the low refractive index material are shown. A comparison with an optical device will be explained. The structural formula of the organic compound used in this reference example is shown below. vinegar.

[0360] [ka]

[0361] (Method of fabricating light-emitting device 1) First, silver (Ag) was deposited to a thickness of 100 nm on a glass substrate by sputtering to form a reflective electrode. Then, a transparent electrode containing indium tin oxide (ITSO) was formed. The first electrode 101 was formed by depositing the ZnO film with a thickness of 10 nm by sputtering. Oh, the electrode area is 4 mm 2 (2mm x 2mm).

[0362] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface was washed with water, and then After baking at 00°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0363] Then, 10 -4 The substrate is placed in a vacuum deposition apparatus whose inside has been reduced in pressure to about Pa, and vacuum deposition is performed. After vacuum baking at 170°C for 30 minutes in the heating chamber of the device, the substrate is left for about 30 minutes. Allow to cool.

[0364] Next, the first electrode 101 is formed so that the surface on which the first electrode 101 is formed faces downward. The substrate was fixed to a substrate holder provided in a vacuum deposition apparatus, and the following was formed on the first electrode 101: N,N-bis(4-cyclohexylphenyl) represented by the above structural formula (i) was prepared by a vapor deposition method. -9,9,-Dimethyl-9H-fluoren-2-amine (abbreviation: dchPAF) and electron The weight ratio of dchPAF to OCHD-001 was 1:0.05 (=dchPAF:OC A hole injection layer 111 having a thickness of 10 nm was formed by co-evaporation so as to obtain a thickness of 10 nm (HD-001).

[0365] On the hole injection layer 111, dchPAF was evaporated to a thickness of 125 nm to form a hole transport layer 112. .

[0366] Next, N,N-bis[4-(diphenyl ether)-(phenylene ... Benzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfB B1TP) was evaporated to a thickness of 10 nm to form an electron blocking layer.

[0367] Thereafter, 9-(1-naphthyl)-10-[4-(2-naphthyl) αN-βNPAnth) and the above structural formula (iv ) represented by 3,10-bis[N-(9-phenyl-9H-carbazol-2-yl)- N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3 ,10PCA2Nbf(IV)-02) in a weight ratio of 1:0.015 (=αN-βNP Anth: 3,10PCA2Nbf(IV)-02) was co-evaporated to give a 25 nm An optical layer 113 was formed.

[0368] Then, 2-{4-[9,10-di(2-naphthyl)-2 -anthryl]phenyl}-1-phenyl-1H-benzimidazole (abbreviation: ZADN ) and 8-quinolinolato-lithium (abbreviation: Liq) represented by the above structural formula (vi). Zn2ZnN2O3 and Li2O3 were co-deposited at a weight ratio of 1:1 (=ZADN:Liq) to form an electron transport layer 1 14 was formed.

[0369] After the electron transport layer 114 is formed, Liq is deposited to a thickness of 1 nm to form the electron injection layer 115. Finally, silver (Ag) and magnesium (Mg) were mixed in a volume ratio of 10:1 and the film thickness was 15 nm. The second electrode 102 was formed by co-evaporation so as to obtain the light-emitting device 1. The second electrode 102 is a semi-transmissive / semi-reflective electrode having a function of reflecting light and a function of transmitting light. The light emitting device is a top emission type in which light is extracted from the second electrode 102. The device is also provided with a 1, 3,5-Tri(dibenzothiophen-4-yl)-benzene (abbreviation: DBT3P-II) The light extraction efficiency is improved by depositing 70 nm of

[0370] (Method of manufacturing light-emitting device 2) Light-emitting device 2 is a light-emitting device that uses dchPAF as the hole injection layer and hole transport layer of light-emitting device 1. N-(1,1'-biphenyl-4-yl)-9,9 represented by the above structural formula (viii) -Dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]- The material was changed to 9H-fluorene-2-amine (abbreviation: PCBBiF), and the thickness of the hole transport layer was increased to 11 The light-emitting device was fabricated in the same manner as in the light-emitting device 1, except that the thickness was set to 0 nm.

[0371] The device structures of light-emitting device 1 and light-emitting device 2 are summarized in the table below.

[0372] [Table 2]

[0373] In addition, dchPAF is a material with a refractive index of 1.75 or less for light with a wavelength of 467 nm. Other organic compounds have a refractive index of more than 1.75 for light with a wavelength of 467 nm. The refractive indexes of dchPAF and PCBBiF are shown in Figure 35.

[0374] If the material has anisotropy, the refractive index for ordinary light (ordinary refractive index) The refractive index for the extraordinary light (extra-ordinary) is different from that for the If the thin film to be measured is in such a state, anisotropic analysis can be performed to determine the ordinary refractive index. The refractive index and the extraordinary refractive index can be calculated separately. In the case where the measured material has both ordinary and extraordinary refractive indices, the ordinary refractive index is is used as an indicator.

[0375] The light-emitting device is placed in a nitrogen atmosphere glove box, and the light-emitting device is exposed to the atmosphere. The process of sealing the element with a glass substrate to prevent it from being exposed to light (applying a UV-curable sealant around the element) The UV irradiation is applied only to the sealant so that the light-emitting device is not exposed to the UV. After heat treatment at 80°C for 1 hour under low temperature, the initial characteristics of these light-emitting devices were measured. was carried out.

[0376] The luminance vs. current density characteristics of light-emitting device 1 and light-emitting device 2 are shown in Figure 29. The current efficiency vs. luminance The characteristics are shown in Fig. 30, the brightness-voltage characteristics in Fig. 31, the current-voltage characteristics in Fig. 32, and the blue index The light-brightness characteristics are shown in FIG. 33, and the emission spectrum is shown in FIG. and 1000cd / m for light-emitting device 2 2 The main characteristics in the vicinity are shown in Table 3. A spectroradiometer (Topcon, SR-UL) was used to measure the chromaticity, CIE chromaticity, and emission spectrum. 1R) was used and measurements were taken at room temperature.

[0377] [Table 3]

[0378] 29 to 34 and Table 3, in the blue light emission region, materials with a refractive index of 1.75 or less The light-emitting device 1 used had better current efficiency and blue index than the light-emitting device 2. It was found that this light-emitting device exhibits a color-changing effect. By combining them, a light emitting device with good efficiency can be obtained. [Explanation of symbols]

[0379] 100 Substrates 101 First electrode 102 Second electrode 103 EL layer 111 Hole injection layer 112 Hole transport layer 113 Light-emitting layer 113-1 Emitting layer 113-2 Emitting layer 114 Electron transport layer 115 Electron injection layer 116 Charge generation layer 117 P type layer 118 Electronic Relay Layer 119 Electron injection buffer layer 200 Insulator 201 First electrode 201B First electrode 201G First electrode 201R First electrode 201W First electrode 202 EL layer 203 Second electrode 204 Protective layer 205B Structure with light scattering function 205G Color conversion layer 205R Color conversion layer 205W Color Conversion Layer 205 Color Conversion Layer 206 Black Matrix 207 Light Emitting Devices 207B First Light Emitting Device 207G Second Light Emitting Device 207R Third Light Emitting Device 207W 4th Light Emitting Device 208 pixels 208B First pixel 208G Second Pixel 208R The third pixel 208W 4th Pixel 209 Optical distance 210G Means of providing directionality 210R Means of imparting directionality 215B Color Filter 225R Color Filter 225G Color Filter 225B Color Filter 501 Anode 502 Cathode 511 First Light Emitting Unit 512 Second Light Emitting Unit 513 Charge generation layer 601 Driver circuit section (source line driver circuit) 602 Pixel section 603 Drive circuit section (gate line drive circuit) 604 Sealing substrate 605 Sealing material 607 Space 608 Wiring 609 FPC (Flexible Printed Circuit) 610 Element Substrate 611 Switching FET 612 Current Control FET 613 Anode 614 Insulation 616 EL layer 617 Cathode 618 Light Emitting Devices 623 FET 1001 Board 1002 Undercoat insulating film 1003 Gate insulating film 1006 Gate electrode 1007 Gate electrode 1008 Gate electrode 1020 First interlayer insulating film 1021 Second interlayer insulating film 1022 Electrode 1024R First electrode 1024G First electrode 1024B First electrode 1025 Bulkhead 1028 EL layer 1029 Cathode 1030 space 1031 Sealing substrate 1032 Sealing material 1033 Transparent substrate 1034R Red color conversion layer 1034G Green color conversion layer 1035 Black Matrix 1036 Overcoat layer 1037 Third interlayer insulating film 1040 Pixel section 1041 Drive circuit section 1042 Periphery 2100 Robot 2110 Arithmetic equipment 2101 Illuminance sensor 2102 Microphone 2103 Upper Camera 2104 Speaker 2105 Display 2106 Lower Camera 2107 Obstacle Sensor 2108 Moving mechanism 5000 cabinet 5001 Display section 5002 Display section 5003 Speaker 5004 LED Lamp 5006 Connection terminal 5007 Sensor 5008 Microphone 5012 Support part 5013 Earphones 5100 Cleaning robot 5101 Display 5102 Camera 5103 Brush 5104 Operation button 5150 Portable Information Terminal 5151 Case 5152 Display area 5153 Bend 5120 Garbage 5200 display area 5201 Display area 5202 Display area 5203 Display area 7101 Case 7103 Display section 7105 Stand 7107 Display section 7109 Operation key 7110 Remote control device 7201 Main unit 7202 Case 7203 Display section 7204 Keyboard 7205 External connection port 7206 Pointing Device 7210 Second display unit 7401 Case 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Mike 9310 Mobile Information Terminal 9311 Display Panel 9313 Hinge 9315 Case

Claims

1. A first light emitting device and a first color conversion layer, The first light-emitting device has a light-emitting layer between an anode and a cathode, a layer containing a first organic compound having a refractive index of 1.75 or less for light having a wavelength of 467 nm between the anode and the light-emitting layer; the light-emitting device further comprising a layer containing a second organic compound having a molecular weight of 300 or more and 1200 or less between the cathode and the first color conversion layer.

2. A first light emitting device and a first color conversion layer, The first light-emitting device has a hole injection layer and a light-emitting layer between an anode and a cathode, the hole injection layer is provided in contact with the anode, the hole injection layer contains a first organic compound having a refractive index of 1.75 or less for light with a wavelength of 467 nm, the light-emitting device further comprising a layer containing a second organic compound having a molecular weight of 300 or more and 1200 or less between the cathode and the first color conversion layer.

3. In claim 1 or 2, The cathode has a function of transmitting light.

4. In any one of claims 1 to 3, A light emitting device, wherein the peak wavelength of the emission spectrum obtained from the first light emitting device is in the range of 440 nm to 520 nm.

5. In any one of claims 1 to 3, The first light emitting device emits blue light.

6. In any one of claims 1 to 5, The light-emitting device, wherein the light-emitting substance contained in the light-emitting layer has an emission spectrum with a peak wavelength in the range of 440 nm to 520 nm.

7. In any one of claims 1 to 5, The light-emitting device, wherein the light-emitting material contained in the light-emitting layer emits blue light.

8. In any one of claims 1 to 7, The first color conversion layer comprises quantum dots.

9. In any one of claims 1 to 8, The first light emitting device comprises a microresonant structure.

10. In any one of claims 1 to 9, The light emitting device has a color filter, The light emitting device, wherein the first color conversion layer is located between the first light emitting device and the color filter.

11. A light emitting device according to any one of claims 1 to 10, and at least one of a sensor, an operation button, a speaker, and a microphone; An electronic device having

12. A light emitting device comprising: the light emitting device according to claim 1 ; and at least one of a transistor and a substrate.

13. A lighting device comprising: the light-emitting device according to claim 1 ; and a housing.

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