Light-emitting element

Abstract

To provide a light-emitting element with high luminescence efficiency. [Solution] A light-emitting element comprising a first organic compound, a second organic compound, and a guest material. It is a child. The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than that of the second organic compound. The LUMO level of the test material is higher than that of the first organic compound, and the H of the guest material is higher. The OMO level is lower than the HOMO level of the second organic compound. The guest material is triplet excited. It has the function of converting energy into light. The first organic compound and the second organic The compound and form an excited complex.

Description

[Technical Field]

[0001] One aspect of the present invention relates to a light-emitting element, or a display device having the light-emitting element, an electronic device, and a light Regarding lighting equipment.

[0002] Furthermore, one aspect of the present invention is not limited to the above-mentioned technical field. One aspect of the technical field relates to a product, method, or method of manufacture. Or, one aspect of the present invention. This refers to a process, machine, manufacture, or composition. Regarding the ter. Therefore, the technical aspects of one aspect of the present invention disclosed more specifically herein Examples include semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, lighting devices, energy storage devices, and memory devices. Examples include devices, methods for driving them, or methods for manufacturing them. . [Background technology]

[0003] In recent years, electroluminescence (EL) Research and development of light-emitting devices using this technology are actively underway. The basic configuration of these light-emitting devices is The device has a configuration in which a layer containing a light-emitting material (EL layer) is sandwiched between a pair of electrodes. By applying a voltage between them, light emission can be obtained from the light-emitting material.

[0004] Since the aforementioned light-emitting element is self-illuminating, the display device using it offers excellent visibility and battery life. It has advantages such as not requiring a light source and consuming little power. Furthermore, the display device is thin It can be manufactured in a lightweight form and has advantages such as high response speed.

[0005] An organic compound is used as the luminescent material, and an EL layer containing the luminescent material is provided between a pair of electrodes. In the case of a light-emitting element (for example, an organic EL element), by applying a voltage between a pair of electrodes... Electrons are injected from the cathode and holes from the anode into the light-emitting EL layer. A flow occurs. Then, the injected electrons and holes recombine to form a luminescent organic compound. The compound enters an excited state, and light emission can be obtained from the excited luminescent organic compound.

[0006] The types of excited states that organic compounds can form include singlet excited states (S * ) and triplet excitation Status (T * ) and the emission from the singlet excited state is fluorescence, and the emission from the triplet excited state is phosphorus It is called light. Also, the statistical generation ratio of these in light-emitting elements is S * :T * = The ratio is 1:3. Therefore, compared to light-emitting elements using fluorescent compounds, Light-emitting devices using phosphorescent compounds (phosphorescent compounds) can achieve higher luminescence efficiency. This becomes possible. Therefore, phosphorescent compounds that can convert triplet excited states into luminescence. In recent years, there has been a great deal of activity in developing light-emitting elements using this technology (see, for example, Patent Document 1).

[0007] The energy required to excite an organic compound is determined by the LUMO level and HOM level of the organic compound. It depends on the energy difference with the O level, and that energy difference is roughly equal to the energy of the singlet excited state. This corresponds to: In light-emitting devices using phosphorescent compounds, the triplet excitation energy corresponds to the emission. It is converted into energy. Therefore, the singlet excited state and triplet excited state formed by organic compounds When the energy difference between the initial state and the starting state is large, the energy required to excite an organic compound is Therefore, the energy equivalent to this energy difference becomes higher than the energy of the light emission. The difference between the energy required to excite an organic compound and the energy of light emission is the energy of light emission. In the device, an increase in the drive voltage affects the device characteristics. Therefore, reduce the drive voltage. Methods for doing so are being explored (see Patent Document 2).

[0008] Furthermore, among light-emitting devices using phosphorescent compounds, in particular, light-emitting devices that exhibit blue light emission... Therefore, it is difficult to develop stable compounds with high triplet excitation energy levels. It has not yet been put into practical use. Therefore, the development of stable phosphorescent compounds with high luminescence efficiency is necessary. There is a demand for the development of highly reliable phosphorescent light-emitting devices that exhibit high luminous efficiency. It is in demand. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2010-182699 [Patent Document 2] Japanese Patent Publication No. 2012-212879 [Overview of the project] [Problems that the invention aims to solve]

[0010] Iridium complexes are known as phosphorescent compounds that exhibit high luminescence efficiency. As an iridium complex possessing luminescence energy, it has a nitrogen-containing five-membered heterocyclic skeleton as a ligand. Iridium complexes are known. This nitrogen-containing five-membered heterocyclic skeleton has a high triplet excitation energy. It has a nitrogen-containing six-membered heterocyclic skeleton, but its electron-accepting ability is lower compared to that of a nitrogen-containing five-membered skeleton. Iridium complexes with a heterocyclic ligand have high LUMO levels and attract electron carriers. It is difficult to introduce into iridium complexes that have a nitrogen-containing five-membered heterocyclic skeleton as a ligand. Therefore, excitation by direct carrier recombination is difficult, making it difficult to induce efficient emission. .

[0011] Therefore, in one aspect of the present invention, a light-emitting element having a phosphorescent compound and high luminescence efficiency is provided. One of the objectives is to provide a light-emitting device with reduced power consumption. Alternatively, in one aspect of the present invention, a light-emitting device with reduced power consumption is provided. One of the objectives is to provide an element. Alternatively, in one aspect of the present invention, a highly reliable generator is provided. One objective is to provide an optical element. Alternatively, in one aspect of the present invention, a novel compound is used. One of the objectives is to provide a novel compound. Alternatively, in one aspect of the present invention, a novel compound is provided. One objective is to provide an optical element. Alternatively, in one aspect of the present invention, a novel light-emitting element is provided. One of the objectives is to provide a novel light-emitting device. Alternatively, in one aspect of the present invention, a novel light-emitting device is provided. One of the objectives is to provide a novel display device. This will be one of the challenges.

[0012] Furthermore, the description of the above problems does not preclude the existence of other problems. Also, one aspect of the present invention is not necessarily However, it is not necessary to solve all of these problems. Other issues not mentioned above should be described in the specification, etc. This is self-evident, and it is possible to extract issues other than those mentioned above from the description in the specification, etc. ru. [Means for solving the problem]

[0013] One aspect of the present invention provides an excitation complex that can efficiently excite a phosphorescent compound. It is a light-emitting element. Furthermore, it is a novel phosphorescent material that can exhibit high luminescence energy. This is a light-emitting element that contains a composite material.

[0014] Therefore, one aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having a material, wherein the LUMO level of the first organic compound is the same as that of the second organic compound Lower than the LUMO level of the substance, the HOMO level of the first organic compound is lower than the H level of the second organic compound. The energy difference between the LUMO level and the HOMO level of the guest material is lower than the OMO level. The energy difference between the LUMO level of organic compound 1 and the HOMO level of organic compound 2. More specifically, the guest material possesses the ability to convert triplet excitation energy into luminescence. The first organic compound and the second organic compound have combinations that form an excited complex. It is an optical element.

[0015] Another aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having the LUMO level of the first organic compound is the LUMO level of the second organic compound The HOMO level of the first organic compound is lower than the LUMO level of the second organic compound. The LUMO level of the guest material is lower than the MO level, and is lower than the LUMO level of the first organic compound. The HOMO level of the guest material is high, and the HOMO level of the guest material is lower than that of the second organic compound. The material has the function of converting triplet excitation energy into light emission, and the first organic compound This is a light-emitting element in which a compound and a second organic compound form an excited complex.

[0016] Another aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having the LUMO level of the first organic compound is the LUMO level of the second organic compound The HOMO level of the first organic compound is lower than the LUMO level of the second organic compound. The LUMO level of the guest material is lower than the MO level, and is the same as the LUMO level of the first organic compound. And so the HOMO level of the guest material is lower than the HOMO level of the second organic compound. The material has the function of converting triplet excitation energy into light emission, and the first This is a light-emitting element in which an organic compound and a second organic compound form an excited complex.

[0017] Another aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having the LUMO level of the first organic compound is the LUMO level of the second organic compound The HOMO level of the first organic compound is lower than the LUMO level of the second organic compound. The LUMO level of the guest material is lower than the MO level, and is lower than the LUMO level of the first organic compound. The HOMO level of the guest material is high, and is equivalent to the HOMO level of the second organic compound. The material has the function of converting triplet excitation energy into light emission, and the first This is a light-emitting element in which an organic compound and a second organic compound form an excited complex.

[0018] Another aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having the following characteristics, wherein the reduction potential of the first organic compound is the reduction potential of the second organic compound The oxidation potential of the first organic compound is higher than the original potential, and is higher than the oxidation potential of the second organic compound. The reduction potential of the guest material is lower than that of the first organic compound, and the oxidation potential of the guest material is lower. The potential is higher than that of the second organic compound, and the guest material emits triplet excitation energy. Having the function of being converted into light, the first organic compound and the second organic compound are excited This is a light-emitting element that uses a combination of elements to form a complex.

[0019] Another aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having the following characteristics, wherein the reduction potential of the first organic compound is the reduction potential of the second organic compound The oxidation potential of the first organic compound is higher than the original potential, and is higher than the oxidation potential of the second organic compound. The reduction potential of the guest material is equivalent to that of the first organic compound, and the acid of the guest material The oxidation potential is higher than that of the second organic compound, and the guest material has a triplet excitation energy. It has the function of converting into light, and comprises a first organic compound and a second organic compound, This is a light-emitting element that uses a combination of elements to form an excited complex.

[0020] Another aspect of the present invention comprises a first organic compound, a second organic compound, and a guest material. A light-emitting element having the following characteristics, wherein the reduction potential of the first organic compound is the reduction potential of the second organic compound The oxidation potential of the first organic compound is higher than the original potential, and is higher than the oxidation potential of the second organic compound. The reduction potential of the guest material is lower than that of the first organic compound, and the oxidation potential of the guest material is lower. The position is equivalent to the oxidation potential of the second organic compound, and the guest material has a triplet excitation energy. It has the function of converting into light, and comprises a first organic compound and a second organic compound, This is a light-emitting element that uses a combination of elements to form an excited complex.

[0021] Furthermore, in each of the above configurations, the LUMO level of the first organic compound and the second organic compound The energy difference between the HOMO level and the transition energy is calculated from the absorption edge of the guest material. It is preferable if the above conditions are met.

[0022] Furthermore, in each of the above configurations, the LUMO level of the first organic compound and the second organic compound The energy difference between the HOMO level and the guest material is greater than or equal to the energy of the emission exhibited by the guest material. preferable.

[0023] Furthermore, in each of the above configurations, the energy between the LUMO level and the HOMO level of the guest material The difference is greater than 0.4 eV from the transition energy calculated from the absorption edge of the guest material. preferable.

[0024] Furthermore, in each of the above configurations, the energy between the LUMO level and the HOMO level of the guest material The difference is preferably 0.4 eV or greater than the energy of the luminescence exhibited by the guest material.

[0025] Furthermore, in each of the above configurations, the emission spectrum of the guest material is 400 nm. Preferably, there is at least one peak in the wavelength region below 505 nm.

[0026] Furthermore, in each of the above configurations, the excitation complex has the function of supplying excitation energy to the guest material. It is preferable that it has the following characteristics. Furthermore, the emission spectrum exhibited by the excited complex is the lowest of the guest material. It is preferable that it has a region that overlaps with the energy absorption band.

[0027] Furthermore, in each of the above configurations, it is preferable that the guest material contains iridium. The material has a ligand that coordinates to iridium, and the ligand has a nitrogen-containing five-membered heterocyclic skeleton. This is preferable. Furthermore, the ligand has a triazole skeleton or an imidazole skeleton. preferable.

[0028] Another aspect of the present invention is an iridium complex represented by the general formula (G1).

[0029] [ka]

[0030] In general formula (G1), Ar 1 represents a substituted or unsubstituted first aryl group having 6 to 13 carbon atoms. Also, Ar represents a substituted or unsubstituted second aryl group having 6 to 13 carbon atoms. Also, Q 2 represents a substituted or unsubstituted second aryl group having 6 to 13 carbon atoms. Also, Q and Q 1 and Q 2 each independently represent N or C-R, and R represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted third aryl group having 6 to 13 carbon atoms. Note that at least one of Q and Q has C-R. Also, at least one of the first aryl group to the third aryl group 1 and Q 2 has a cyano group.

[0031]

[0032]

Chemical formula

[0033] In general formula (G2), Ar 1 represents a substituted or unsubstituted first aryl group having 6 to 13 carbon atoms. Also, R to R 1 to R 4 each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, a substituted or unsubstituted fourth aryl group having 6 to 13 carbon atoms, or a cyano group. Also, Q and Q each independently represent N or C-R, and R represents hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 1 and Q 2 each independently represent N or C-R, and R represents hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, a substituted or unsubstituted fourth aryl group having 6 to 13 carbon atoms, or a cyano group. Also, Q A haloalkyl group with up to 6 carbon atoms, or a third substituted or unsubstituted aryl group with 6 to 13 carbon atoms. It represents one of the bases. Note that Q 1 and Q 2 At least one of them has CR. Also, The first aryl group, the third aryl group, the fourth aryl group, and R 1 ~R 4 at least Another has a cyano group.

[0034] Another aspect of the present invention is an iridium complex represented by the general formula (G3).

[0035] [ka]

[0036] In general formula (G3), Ar 1 The first A has 6 to 13 carbon atoms, which are substituted or unsubstituted. It represents a reel group. Also, R 1 ~R 4 These are, independently, hydrogen and aluminum atoms having 1 to 6 carbon atoms. Kill group, cycloalkyl group having 3 to 6 carbon atoms, substituted or unsubstituted group having 6 to 13 carbon atoms It represents either a fourth aryl group or a cyano group. Also, R 5 is hydrogen, carbon-1 Alkyl alkyl groups up to 6 carbon atoms, haloalkyl groups with 1 to 6 carbon atoms, or substitutions with 6 to 13 carbon atoms are also possible. It represents either the first aryl group or an unsubstituted third aryl group. Riehl group, fourth aryl group, and R 1 ~R 4 At least one of them has a cyano group.

[0037] Another aspect of the present invention is an iridium complex represented by the general formula (G4).

[0038] [ka]

[0039] In general formula (G4), Ar 1 The first A has 6 to 13 carbon atoms, which are substituted or unsubstituted. It represents a reel group. Also, R 1 ~R 4 These are, independently, hydrogen and aluminum atoms having 1 to 6 carbon atoms. Kill group, cycloalkyl group having 3 to 6 carbon atoms, or substituted or unsubstituted group having 6 to 13 carbon atoms. It represents one of the fourth aryl groups in the substitution. Also, R 5 and R 6 Each of them operates independently. Hydrogen, C1 to C6 alkyl groups, C1 to C6 haloalkyl groups, or C6 It represents one of the substituted or unsubstituted third aryl groups up to 13. Also, the first aryl group aryl group, third aryl group, fourth aryl group, and R 1 ~R 4 At least one of them is It has that group.

[0040] Furthermore, in each of the above configurations, 1 is a substituted or unsubstituted phenyl group, and phenyl The group preferably has a cyano group.

[0041] Another aspect of the present invention is an iridium complex represented by the general formula (G5).

[0042] [ka]

[0043] In the general formula (G5), R 1 ~R 4 These are, independently, hydrogen and carbon atoms with 1 to 6 carbon atoms. Alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or substitutions of 6 to 13 carbon atoms R represents any of the unsubstituted aryl groups. 5 It consists of hydrogen and alkyl groups with 1 to 6 carbon atoms. A C1-C6 haloalkyl group, or a C6-C13 substituted or unsubstituted group. It represents one of the aryl groups. Also, R 7 and R 11 This is an alkyl group having 1 to 6 carbon atoms. Represents R 7 and R 11 They have the same structure as each other. Also, R 8 ~R 10 These are, Independently, hydrogen, C1-C6 alkyl groups, C3-C6 cycloalkyl groups, substitution Alternatively, it represents either an unsubstituted phenyl group or a cyano group, R 8 ~R 10 few At least one of them has a cyano group.

[0044] Another aspect of the present invention is an iridium complex represented by the general formula (G6).

[0045] [ka]

[0046] In general formula (G6), R 1 ~R 4 These are, independently, hydrogen and carbon atoms with 1 to 6 carbon atoms. Alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or substitutions of 6 to 13 carbon atoms R represents any of the unsubstituted aryl groups. 5 and R 6 Each of them independently, water A C1-C6 alkyl group, a C1-C6 haloalkyl group, or a C6-C6 ion It represents either a substituted or unsubstituted aryl group from 13 to 13. Also, R 7 and R 11 teeth, R represents an alkyl group having 1 to 6 carbon atoms.7 and R 11 have the same structure with each other. Also, R 8 to R 10 each independently represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, a substituted or unsubstituted phenyl group, or a cyano group, and at least one of R to R 8 has a cyano group. 10

[0047] Another aspect of the present invention is an iridium complex represented by the general formula (G7).

[0048]

Chemical formula

[0049] In the general formula (G7), Ar 1 represents a substituted or unsubstituted first aryl group having 6 to 13 carbon atoms. Also, R to R 1 to R 4 each independently represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or a substituted or unsubstituted fourth aryl group having 6 to 13 carbon atoms. Also, R represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or a substituted or unsubstituted third aryl group having 6 to 13 carbon atoms. Also, at least one of the first aryl group, the third aryl group, the fourth aryl group, and R 6 to R has a cyano group. The fourth aryl group, and R 1 to R 4

[0050] Ar described in the above configuration 1 is a substituted or unsubstituted phenyl group, and the phenyl group preferably has a cyano group.

[0051] Another aspect of the present invention is an iridium complex represented by the general formula (G8).

[0052] [ka]

[0053] In the general formula (G8), R 1 ~R 4 These are, independently, hydrogen and carbon atoms with 1 to 6 carbon atoms. Alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or substitutions of 6 to 13 carbon atoms R represents any of the unsubstituted aryl groups. 6 It consists of hydrogen and alkyl groups with 1 to 6 carbon atoms. A C1-C6 haloalkyl group, or a C6-C13 substituted or unsubstituted group. It represents one of the aryl groups. Also, R 7 and R 11 This is an alkyl group having 1 to 6 carbon atoms. Represents R 7 and R 11 They have the same structure as each other. Also, R 8 ~R 10 These are, Independently, hydrogen, C1-C6 alkyl groups, C3-C6 cycloalkyl groups, substitution Alternatively, it represents either an unsubstituted phenyl group or a cyano group, R 8 ~R 10 few At least one of them has a cyano group.

[0054] Another aspect of the present invention is a light-emitting element having the iridium complex described in each of the above configurations. be.

[0055] Another aspect of the present invention is the iridium complex described in each of the above configurations and the first organic compound A light-emitting element having a first organic compound and a second organic compound, wherein the LUMO level of the first organic compound The level is lower than the LUMO level of the second organic compound, and the HOMO level of the first organic compound is lower than the HOMO level of the second organic compound, and the energy difference between the LUMO level and the HOMO level of the iridium complex is larger than the energy difference between the LUMO level of the first organic compound and the HOMO level of the second organic compound, and it is a light-emitting device of a combination in which the first organic compound and the second organic compound form an excited complex.

[0056] Moreover, another aspect of the present invention is a light-emitting device having the iridium complex described in each of the above configurations, the first organic compound, and the second organic compound, wherein the LUMO level of the first organic compound is lower than the LUMO level of the second organic compound, and the HOMO level of the first organic compound is lower than the HOMO level of the second organic compound, the LUMO level of the iridium complex is higher than the LUMO level of the first organic compound, the HOMO level of the iridium complex is lower than the HOMO level of the second organic compound, and it is a light-emitting device of a combination in which the first organic compound and the second organic compound form an excited complex.

[0057] Moreover, another aspect of the present invention is a light-emitting device having the iridium complex described in each of the above configurations, the first organic compound, and the second organic compound, wherein the LUMO level of the first organic compound is lower than the LUMO level of the second organic compound, and the HOMO level of the first organic compound is lower than the HOMO level of the second organic compound, the LUMO level of the iridium complex is equivalent to the LUMO level of the first organic compound, the HOMO level of the iridium complex is lower than the HOMO level of the second organic compound, and it is a light-emitting device of a combination in which the first organic compound and the second organic compound form an excited complex.

[0058] Another aspect of the present invention is the iridium complex described in each of the above configurations and the first organic compound A light-emitting element having a first organic compound and a second organic compound, wherein the LUMO level of the first organic compound The level is lower than the LUMO level of the second organic compound, and the HOMO level of the first organic compound is, The LUMO level of the iridium complex is lower than the HOMO level of the second organic compound. The HOMO level of the iridium complex is higher than the LUMO level of the organic compound, and is higher than that of the second organic compound. It is equivalent to the HOMO level, and the first organic compound and the second organic compound form an excited complex. It is a light-emitting element formed by a combination of elements.

[0059] Another aspect of the present invention is the iridium complex described in each of the above configurations and the first organic compound A light-emitting element having a first organic compound and a second organic compound, wherein the reduction potential of the first organic compound is The oxidation potential of the first organic compound is higher than the reduction potential of the second organic compound, and the oxidation potential of the first organic compound is higher than the reduction potential of the second organic compound. The reduction potential of the iridium complex is higher than the oxidation potential of the compound, and is higher than the reduction potential of the first organic compound. The oxidation potential of the iridium complex is lower, and the oxidation potential of the iridium complex is higher than that of the second organic compound. This is a light-emitting element in which an organic compound and a second organic compound form an excited complex.

[0060] Another aspect of the present invention is the iridium complex described in each of the above configurations and the first organic compound A light-emitting element having a first organic compound and a second organic compound, wherein the reduction potential of the first organic compound is The oxidation potential of the first organic compound is higher than the reduction potential of the second organic compound, and the oxidation potential of the first organic compound is higher than the reduction potential of the second organic compound. The reduction potential of the iridium complex is higher than that of the compound, and is higher than that of the first organic compound. They are equivalent, and the oxidation potential of the iridium complex is higher than that of the second organic compound. This is a light-emitting element in which an organic compound and a second organic compound form an excited complex. ru.

[0061] Another aspect of the present invention is the iridium complex described in each of the above configurations and the first organic compound A light-emitting element having a first organic compound and a second organic compound, wherein the reduction potential of the first organic compound is The oxidation potential of the first organic compound is higher than the reduction potential of the second organic compound, and the oxidation potential of the first organic compound is higher than the reduction potential of the second organic compound. The reduction potential of the iridium complex is higher than the oxidation potential of the compound, and is higher than the reduction potential of the first organic compound. The oxidation potential of the iridium complex is low, and is equivalent to the oxidation potential of the second organic compound, and the first This is a light-emitting element in which an organic compound and a second organic compound form an excited complex. ru.

[0062] Furthermore, in each of the above configurations, the excited complex provides excitation energy to the iridium complex. It is preferable that it has a function. Furthermore, the emission spectrum exhibited by the excited complex is of the iridium complex. It is preferable that the region overlaps with the lowest energy absorption band.

[0063] Furthermore, in the above configuration, the LUMO level of the first organic compound and the H of the second organic compound The energy difference between the OMO level and the transition energy calculated from the absorption edge of the iridium complex is the transition energy. - Preferably, it should be greater than or equal to this.

[0064] Furthermore, in the above configuration, the LUMO level of the first organic compound and the H of the second organic compound The energy difference between the OMO level and the other level is greater than the energy of the luminescence exhibited by the iridium complex. And that is preferable.

[0065] Furthermore, in each of the above configurations, the first organic compound has the function of transporting electrons. Preferably, the second organic compound has the function of transporting holes. The first organic compound has a π-electron-deficient heteroaromatic ring skeleton, and the second organic compound has a π-electron-deficient heteroaromatic ring skeleton. It is preferable that the skeleton has at least one of either an excess heteroatomic aromatic ring skeleton or an aromatic amine skeleton.

[0066] Another aspect of the present invention involves the light-emitting element of each of the above configurations and a color filter or transistor. A display device having at least one of the ZISTA. Another aspect of the present invention is the The electronic device comprises a display device and at least one of a housing or a touch sensor. Furthermore, another aspect of the present invention relates to the light-emitting element of each of the above configurations and a housing or touch sensor. It is a lighting device having at least one of the following. Another aspect of the present invention is a lighting device having a light-emitting element. This includes not only optical devices but also electronic devices that have light-emitting devices. A light-emitting device refers to an image display device or a light source (including lighting devices). A connector for the optical device, for example, an FPC (Flexible Printed Circuit) t) Display module with TCP (Tape Carrier Package) attached A display module with a printed circuit board attached to the TCP, or a light-emitting element with a C The OG (Chip On Glass) method directly mounts the IC (integrated circuit) to the display. Modules may also include light-emitting devices. [Effects of the Invention]

[0067] According to one aspect of the present invention, to provide a light-emitting element having a phosphorescent compound and high luminescence efficiency. This is possible. Alternatively, according to one aspect of the present invention, a light-emitting element with reduced power consumption can be provided. This can be achieved. Alternatively, according to one aspect of the present invention, a highly reliable light-emitting element can be provided. Yes, it is possible. Or, according to one aspect of the present invention, a novel compound can be provided. Or According to one aspect of the present invention, a light-emitting element having a novel compound can be provided. According to one aspect of the present invention, a novel light-emitting element can be provided. Or, the present invention In one embodiment, a novel light-emitting device can be provided. Alternatively, in one embodiment of the present invention, This allows us to provide a novel display device.

[0068] Furthermore, the description of these effects does not preclude the existence of other effects. One aspect of the present invention is: It is not necessarily required to have all of these effects. Other effects are described in the specification. This is obvious from the descriptions in the specifications, drawings, and claims, and the descriptions in the specifications, drawings, and claims Therefore, it is possible to extract effects other than those mentioned above. [Brief explanation of the drawing]

[0069] [Figure 1] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 2] A diagram illustrating the correlation of energy bands and energy levels in the light-emitting layer of a light-emitting element according to one embodiment of the present invention. [Figure 3] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 4] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 5] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 6] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 7] A schematic cross-sectional diagram illustrating a method for manufacturing a light-emitting element according to one embodiment of the present invention. [Figure 8] A schematic cross-sectional diagram illustrating a method for manufacturing a light-emitting element according to one embodiment of the present invention. [Figure 9] A top view and a schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 10] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 11] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 12] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 13] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 14] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 15] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 16] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 17] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 18] A block diagram and a circuit diagram illustrating a display device according to one embodiment of the present invention. [Figure 19] A circuit diagram illustrating the pixel circuit of a display device according to one embodiment of the present invention. [Figure 20] A circuit diagram illustrating the pixel circuit of a display device according to one embodiment of the present invention. [Figure 21] A perspective view showing an example of a touch panel according to one aspect of the present invention. [Figure 22] A cross-sectional view showing an example of a display device and a touch sensor according to one embodiment of the present invention. [Figure 23] A cross-sectional view showing an example of a touch panel according to one aspect of the present invention. [Figure 24] A block diagram and timing chart diagram of a touch sensor according to one aspect of the present invention. [Figure 25] Circuit diagram of a touch sensor according to one aspect of the present invention. [Figure 26] A perspective view illustrating a display module according to one embodiment of the present invention. [Figure 27] A diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 28] A diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 29] A perspective view illustrating a display device according to one embodiment of the present invention. [Figure 30] A perspective view and a cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. [Figure 31] A cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. [Figure 32] A diagram illustrating an electronic device and a lighting device according to one embodiment of the present invention. [Figure 33] A diagram illustrating a lighting device according to one embodiment of the present invention. [Figure 34] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 35] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 36] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 37] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 38] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 39] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 40] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 41] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 42] A schematic cross-sectional view illustrating a light-emitting element according to an embodiment. [Figure 43] A diagram illustrating the emission spectrum of the host material in the example. [Figure 44] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 45] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 46] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 47]A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 48] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 49] A diagram illustrating the absorption spectrum of a compound in an example. [Figure 50] A diagram illustrating the reliability test results of the light-emitting element according to the embodiment. [Figure 51] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 52] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 53] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 54] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 55] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 56] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 57] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 58] A diagram illustrating the current density-voltage characteristics of a light-emitting element according to an embodiment. [Figure 59] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 60] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 61] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 62] A diagram illustrating the reliability test results of the light-emitting element according to the embodiment. [Figure 63] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 64] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 65] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 66] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 67] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 68] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 69] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 70] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 71] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 72] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 73] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 74] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 75] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 76] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 77] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 78] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 79] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 80] A diagram illustrating a liquid chromatograph of a compound according to one embodiment of the present invention. [Figure 81] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 82] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 83]A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 84] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Figure 85] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 86] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 87] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 88] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 89] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 90] A diagram illustrating the emission spectrum of the host material in the example. [Figure 91] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 92] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 93] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 94] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 95] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 96] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 97] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 98] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 99] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 100] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 101]A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 102] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 103] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 104] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 105] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 106] A diagram illustrating the emission spectrum of the host material in the example. [Figure 107] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 108] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 109] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 110] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 111] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 112] A diagram illustrating the absorption spectrum of a compound in an example. [Figure 113] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 114] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 115] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 116] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 117] A diagram illustrating the light emission behavior of a light-emitting element according to an embodiment. [Figure 118] A diagram illustrating the NMR chart of a compound according to one embodiment of the present invention. [Figure 119] A diagram illustrating the absorption spectrum and emission spectrum of a compound according to one embodiment of the present invention. [Modes for carrying out the invention]

[0070] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is as follows The description is not limited to the present invention, and the form and details may not depart from the spirit and scope of the present invention. It is possible to change this in various ways. Therefore, the present invention can be described in the embodiments shown below. It is not interpreted as being limited to volume.

[0071] For the sake of ease of understanding, the position, size, and scope of each component shown in the drawings, etc., are as follows: The actual location, size, and range may not be represented. Therefore, the disclosed invention may not reflect the actual location, size, or range. It is not necessarily limited to the location, size, or scope disclosed in drawings, etc.

[0072] Furthermore, in this specification, the ordinal numbers used as "1st," "2nd," etc., are used for convenience. The order of processes or stacking may not be indicated. For example, "the first" may be written as "the second" or This can be replaced with "third," etc., as appropriate in the explanation. The ordinal numbers used to specify one aspect of this invention may not be the same. be.

[0073] Furthermore, in this specification and other documents, when describing the structure of the invention using drawings, the same thing is used The symbols used may be consistent across different drawings.

[0074] Furthermore, in this specification, the terms "membrane" and "layer" are interchangeable. It is possible to change the term. For example, the term "conductive layer" can be changed to the term "conductive film." It may be possible to change it. Or, for example, change the term "insulating film" to "insulating layer". In some cases, it may be possible to change the terminology to this.

[0075] In this specification, etc., the singlet excited state (S * ) is a single with excitation energy This refers to a singlet state. Furthermore, the lowest singlet excitation energy level (S1 level) is: This refers to the lowest excitation energy level of a singlet excited state. Also, the triplet excited state (T * ) is a triplet state that has excitation energy. The lowest energy level (T1 level) is the same as the excitation energy level of the lowest triplet excited state. And so it is. Furthermore, in this specification, the terms singlet excited state and singlet excitation energy are used without further explanation. Even when the term "level" is used, it may refer to the lowest singlet excited state and the S1 level. Furthermore, even when referred to as triplet excited states and triplet excited energy levels, This may represent the lowest triplet excited state and the T1 level.

[0076] Furthermore, in this specification, a fluorescent compound is defined as a compound that relaxes from a singlet excited state to a ground state. These are compounds that emit light in the visible light region when excited. On the other hand, phosphorescent compounds are compounds that exhibit triplet excitation. This compound emits light in the visible light region at room temperature when relaxing from one state to the ground state. In other words, phosphorescent compounds are compounds that can convert triplet excitation energy into visible light. That is the case.

[0077] Furthermore, the phosphorescence emission energy or triplet excitation energy is the shortest wavelength side of the phosphorescence emission. It can be derived from the wavelength of the emission peak (including the shoulder). Note that this phosphorescence emission is Perform time-resolved photoluminescence in a low-temperature environment (e.g., 10K). It can be observed. In addition, the emission energy of thermally activated delayed fluorescence is the same as that of thermally activated delayed fluorescence. It can be derived from the wavelength of the shortest wavelength emission peak (including the shoulder) of the light.

[0078] In this specification, room temperature refers to any temperature between 0°C and 40°C.

[0079] Furthermore, in this specification, the blue wavelength region refers to waves between 400 nm and 505 nm. It is a long wavelength region, and blue emission means that there is at least one emission spectral peak in that wavelength region. This is the type of light emission. Furthermore, the green wavelength region refers to the wavelength range between 505 nm and less than 580 nm. Therefore, green emission is defined as emission having at least one emission spectral peak in the wavelength region. It is light. Furthermore, the red wavelength range is the wavelength range between 580 nm and 680 nm. Red emission is defined as emission having at least one emission spectral peak in the wavelength region. ru.

[0080] (Embodiment 1) In this embodiment, a light-emitting element according to one aspect of the present invention will be described below using Figures 1 and 2. I will reveal it.

[0081] <Example of light-emitting element configuration> First, regarding the configuration of a light-emitting element according to one aspect of the present invention, use Figures 1(A) and (B) to show the following: I will explain below.

[0082] Figure 1(A) is a schematic cross-sectional view of a light-emitting element 150 according to one embodiment of the present invention.

[0083] The light-emitting element 150 has a pair of electrodes (electrode 101 and electrode 102), and between the pair of electrodes It has an EL layer 100 provided therein. The EL layer 100 has at least an emissive layer 130. .

[0084] Furthermore, the EL layer 100 shown in Figure 1(A) includes, in addition to the light-emitting layer 130, a hole injection layer 111, and It has functional layers such as a pore transport layer 112, an electron transport layer 118, and an electron injection layer 119.

[0085] In this embodiment, of the pair of electrodes, electrode 101 is used as the anode, and electrode 1 Although 02 is described as the cathode, this is not the case for the configuration of the light-emitting element 150. Then, electrode 101 is used as the cathode and electrode 102 as the anode, and the stacking of each layer between these electrodes is done in the reverse order. It may also be arranged in this order. That is, from the anode side, a hole injection layer 111, a hole transport layer 112, and The order in which the optical layer 130, electron transport layer 118, and electron injection layer 119 are stacked should be as follows. .

[0086] Note that the configuration of the EL layer 100 is not limited to the configuration shown in Figure 1(A), and the hole injection layer 111 At least one of the hole transport layer 112, electron transport layer 118, and electron injection layer 119 selected It is sufficient to have a configuration that has one of either. Alternatively, the EL layer 100 can be a hole or electron injection To reduce barriers, improve hole or electron transport, or inhibit hole or electron transport. It has a functional layer that has functions such as being able to suppress the quenching phenomenon caused by electrodes. It may also be configured as follows. Note that even if each functional layer is a single layer, a configuration in which multiple layers are stacked may also be possible. It may be possible.

[0087] Figure 1(B) is a schematic cross-sectional view showing an example of the light-emitting layer 130 shown in Figure 1(A). The light-emitting layer 130 shown in B) has a host material 131 and a guest material 132. The host material 131 comprises organic compound 131_1 and organic compound 131_2.

[0088] Furthermore, as the guest material 132, a luminescent organic compound may be used, and the luminescent organic compound As for the chemical compounds, they are substances that can emit phosphorescence (hereinafter also called phosphorescent compounds). This is preferable. In the following description, a phosphorescent compound is used as the guest material 132. The configuration will be explained. Note that guest material 132 may be interpreted as a phosphorescent compound. stomach.

[0089] <Light-emitting mechanism of light-emitting element> Next, the light-emitting mechanism of the light-emitting layer 130 will be explained below.

[0090] The organic compound 131_1 and organic compound contained in the host material 131 in the light-emitting layer 130 Substance 131_2 is an excited complex (exciplex, exciplex or Excipl Forms an ex (also called ex).

[0091] The combination of organic compound 131_1 and organic compound 131_2 forms an excited complex. Any combination that allows for this is acceptable, but one of them must have the function of transporting holes (hole transportability). It is a compound that does one function, and the other is a compound that has the function of transporting electrons (electron transport properties). However, this is more preferable. In this case, it becomes easier to form a donor-acceptor type excitation complex. Excited complexes can be formed efficiently.

[0092] Furthermore, as for the combination of organic compound 131_1 and organic compound 131_2, one of them is The other is the Highest Occupied Molecular Orb It has a HOMO level lower than the ital (also called HOMO) level, and the other lowest air track Road (Lowest Unoccupied Molecular Orbital, LU It is preferable to have a LUMO level lower than the MO level.

[0093] For example, as shown in the energy band diagram in Figure 2(A), organic compound 131_1 is electron When organic compound 131_2 has hole transport properties, organic compound 131_1 The HOMO level of is lower than that of organic compound 131_2, and organic compound 1 The LUMO level of 31_1 is preferably lower than that of organic compound 131_2. stomach.

[0094] At this time, the excited complex formed by organic compound 131_1 and organic compound 131_2 is The energy between the LUMO level of organic compound 131_1 and the HOMO level of organic compound 131_2 The excited complex has an excitation energy that is roughly equivalent to the Gie difference. Also, organic compound 131 The difference between the HOMO level of _1 and the HOMO level of organic compound 131_2, and organic compound 13 The difference between the LUMO level of 1_1 and the LUMO level of organic compound 131_2 is favorable. The energy difference is 0.1 eV or more, and more preferably 0.2 eV or more. By doing so, the electron carriers injected from the pair of electrodes (electrode 101 and electrode 102) The hole carriers are added to organic compound 131_1 and organic compound 131_2, respectively. This is preferable because it makes it easier to access. Note that in Figure 2(A), Host(131_1) represents organic compound 131_1, and Host(131_2) represents organic compound 131_2. Guest(132) represents guest material 132, and ΔE Ex This is organic compound 131_1 This represents the energy difference between the LUMO level and the HOMO level of organic compound 131_2, and ΔE G teeth The notation and symbols representing the energy difference between the LUMO level and the HOMO level of guest material 132. That is the case.

[0095] Furthermore, the HOMO level of guest material 132 is higher than the HOMO level of organic compound 131_2. The LUMO level of guest material 132 is low, and the LUMO level of organic compound 131_1 is low. A higher value is preferable. That is, the LUMO level and HOMO level of the guest material 132 The energy difference (ΔE G ) is the LUMO level of organic compound 131_1 and organic compound 131 Energy difference (ΔE) between the HOMO level of _2 Ex ) is larger. By doing so, guests An excited complex is formed with material 132 and organic compound 131_1 or organic compound 131_2. This can suppress the reaction.

[0096] For example, if the HOMO level of guest material 132 is higher than the HOMO level of organic compound 131_2 The material having the highest HOMO level among the materials of the light-emitting layer 130 is Guess The material 132 is organic compound 131_1, which has the lowest LUMO level. At that time, there is a possibility that an excited complex will be formed between the guest material 132 and the organic compound 131_1. In particular, the relationship between the HOMO level of guest material 132 and the LUMO level of organic compound 131_1 As the energy difference becomes smaller than the energy of the guest material's emission, the guest material An excited complex is more likely to be formed between 132 and the organic compound 131_1. Therefore, the guest material 132 alone is less likely to generate an excited state, resulting in a lower luminescence efficiency of the light-emitting element. I'll have diarrhea.

[0097] Furthermore, the LUMO level of guest material 132 is below the LUMO level of organic compound 131_1. Therefore, among the materials of the light-emitting layer 130, the material with the lowest LUMO level is the guest Of the materials, the one with the highest HOMO level is organic compound 131_2. There is a possibility that an excited complex may be formed between guest material 132 and organic compound 131_2. In particular, the relationship between the LUMO level of guest material 132 and the HOMO level of organic compound 131_2 As the energy difference becomes smaller than the luminescence energy of the guest material, guest material 1 An excited complex is more likely to be formed between 32 and the organic compound 131_2. In this case, Because the excited state is less likely to be generated by the guest material 132 alone, the luminescence efficiency of the light-emitting element decreases. It happens.

[0098] However, in a light-emitting element according to one aspect of the present invention, the guest material 132 and the organic compound To suppress the reaction that forms an excited complex with substance 131_1 or organic compound 131_2. This allows for the creation of light-emitting elements that exhibit high luminescence efficiency.

[0099] Furthermore, the HOMO level of guest material 132 is higher than the HOMO level of organic compound 131_2. The LUMO level of guest material 132 is lower, and the LUMO level of organic compound 131_1 is higher. Therefore, carriers (holes and...) injected from a pair of electrodes (electrode 101 and electrode 102) Of the electrons, the holes injected from the anode are absorbed into the organic compound 131 in the light-emitting layer 130. 2 is easily injected, and electrons injected from the cathode are easily injected into organic compound 131_1. stomach.

[0100] Furthermore, from this perspective, the HOMO level of guest material 132 and organic compound 131_ The HOMO level of 2, or the LUMO level of guest material 132 and organic compound 131_1 The LUMO levels may be equivalent, which is one aspect of the present invention. However, as described below... For this reason, the energy difference (ΔE) between the LUMO level and the HOMO level of guest material 132 G ) However, the LUMO level of organic compound 131_1 and the HOMO level of organic compound 131_2 Energy difference (ΔE Ex It is preferable that it be greater than ).

[0101] The energy difference between the LUMO level of organic compound 131_1 and the HOMO level of organic compound 131_2 Energy difference (ΔE Ex ) are each of organic compound 131_1 and organic compound 131_2 Because it is smaller than the energy difference between the LUMO level and the HOMO level, organic compound 131_1 It is more effective for organic compound 131_2 to form an excited complex than to form an excited state on its own. It becomes energy stable. Also, the relationship between the LUMO level and the HOMO level of guest material 132 Energy difference (ΔE G ) is the LUMO level of organic compound 131_1 and organic compound 131_2 Energy difference (ΔE) from the HOMO level Ex Because it is larger than ), it is injected into the light-emitting layer 130. The excited state formed by the recombination of carriers (holes and electrons) is that of organic compound 13 The excited complex formed by 1_1 and organic compound 131_2 is more energetically stable. Therefore, most of the excited states generated in the light-emitting layer 130 are with the organic compound 131_1. It will exist as an excited complex formed with compound 131_2.

[0102] Furthermore, since guest material 132 is a phosphorescent light-emitting material, it emits triplet excitation energy. It has the ability to convert to a triplet excited state. In addition, the triplet excited state is more efficient than the singlet excited state. The energy is stable. Therefore, the guest material 132 can exhibit light emission with an energy lower than the energy difference (ΔE ) between the LUMO level and the HOMO level. Here, G even when the energy difference (ΔE ) between the LUMO level and the HOMO level of this guest material 132 is larger than the energy difference (ΔE G ) between the LUMO level of the organic compound 131_1 and the HOMO level of the organic compound 131_2, if the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum is equal to or smaller than ΔE , the inventors have found that the excitation energy can be transferred from the exciplex formed by the organic compound 131_1 and the organic compound 131_2 to the guest material 132, and light emission from the guest material 132 can be obtained. When ΔE of the guest material 132 is larger than the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum, a large electric energy corresponding to ΔE Ex is required to directly electrically excite the guest material 132, and the driving voltage increases. However, in the above aspect of the present invention , the exciplex is electrically excited by an electric energy corresponding to ΔE Ex (smaller than ΔE ), and light emission of the guest material can be obtained by energy transfer therefrom. That is, when ΔE is considerably larger than the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum (for example, when the guest material is a blue light-emitting material), in the present invention, the energy difference (ΔE G ) of the guest material 132 is larger than the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum. If it is much larger (for example, when the guest material is a blue light-emitting material), in the present invention, even when the energy difference (ΔE ) between the LUMO level and the HOMO level of the guest material 132 is larger than the energy difference (ΔE G ) between the LUMO level of the organic compound 131_1 and the HOMO level of the organic compound 131_2, if the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum is equal to or smaller than ΔE , the excitation energy can be transferred from the exciplex formed by the organic compound 131_1 and the organic compound 131_2 to the guest material 132, and light emission from the guest material 132 can be obtained. When ΔE of the guest material 132 is larger than the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum, a large electric energy corresponding to ΔE Ex (ΔE G is smaller) is required to directly electrically excite the guest material 132, and the driving voltage increases. However, in the above aspect of the present invention , the exciplex is electrically excited by an electric energy corresponding to ΔE (ΔE G is smaller than ΔE ) between the LUMO level and the HOMO level of the guest material 132, and light emission of the guest material can be obtained by energy transfer therefrom. That is, when ΔE is considerably larger than the emission energy exhibited by the guest material 132 or the transition energy calculated from the absorption spectrum (for example, when the guest material is a blue light-emitting material), in the present One aspect of the invention is beneficial.

[0103] When the guest material 132 contains heavy metals, spin-orbit interaction (the interaction between the spin angular momentum and the orbital angular momentum of electrons) promotes the crossing between the singlet state and the triplet state. Therefore, the transition between the singlet ground state and the triplet excited state in the guest material 132 may not be prohibited. That is, the efficiency of light emission and the probability of absorption related to the transition between the singlet ground state and the triplet excited state of the guest material 132 can be increased. Therefore, the guest material 132 preferably contains a metal element with a large spin-orbit interaction, and particularly preferably contains a platinum group element (ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), or platinum (Pt)), and among them, having iridium can increase the absorption probability related to the direct transition between the singlet ground state and the triplet excited state, which is preferable. Also, as described above, even when the energy difference (ΔE G ) between the LUMO level and the HOMO level of the guest material 132 is larger than the energy difference (ΔE Ex ) between the LUMO level of the organic compound 131_1 and the HOMO level of the organic compound 131_2, if the transition energy (abbreviation: ΔE G_abs ) calculated from the absorption edge of the guest material 132 is equal to or smaller than ΔE Ex , the excitation energy efficiently moves from the exciplex formed by the organic compound 131_1 and the organic compound 131_2 to the guest material 132. As a result, one of the features of one aspect of the present invention is that a light-emitting device with low voltage and high efficiency can be obtained. At this time, ΔE

[0104] G_a bs ≤ΔE Ex <ΔE G (ΔE G_abs is ΔE Ex The following is true: ΔE Ex is ΔE G twist (small) Therefore, the transition energy calculated from the absorption edge of guest material 132 Energy (ΔE) G_abs ) However, the energy between the LUMO level and the HOMO level of guest material 132 Energy difference (ΔE G The mechanism of one embodiment of the present invention is preferred when it is smaller than ). Then, the energy difference (ΔE) between the LUMO level and the HOMO level of guest material 132 is... G )but The transition energy (ΔE) calculated from the absorption edge of guest material 132 G_abs Larger than ) In such cases, the mechanism of one embodiment of the present invention is suitable. More specifically, guest material 13 The energy difference (ΔE) between the LUMO level and the HOMO level of 2 G ) is the absorption of guest material 132 The transition energy (ΔE) calculated from the convergence end G_abs ) is preferable if it is 0.4eV or more greater. It seems so. Also, the energy of the luminescence exhibited by guest material 132 is ΔE G_abs Equivalent to Because it is smaller than that, the energy between the LUMO level and the HOMO level of guest material 132 - Difference (ΔE G ) is 0.4 eV or more higher than the luminescence energy exhibited by guest material 132. It is preferable. Furthermore, the energy of the emission is the emission peak at the shortest wavelength side of the emission spectrum. It can be derived from the wavelength of the peak (including the shoulder).

[0105] Furthermore, the emission wavelength of guest material 132 becomes shorter (the emission energy increases) The energy difference (ΔE) between the LUMO level and the HOMO level of guest material 132. G ) is large Consequently, a large amount of energy is required to electrically excite the guest material. Meanwhile, the transition energy (ΔE) calculated from the absorption edge of guest material 132 G_abs ) is ΔE Ex If it is equivalent to or smaller than ΔE, then by the present invention G ΔE is much smaller than Ex Since the guest material 132 can be excited with a certain amount of energy, the energy consumption of the light-emitting element Power can be reduced. Therefore, the transition calculated from the absorption edge of guest material 132 Transfer energy (ΔE G_abs ) and the LUMO level and HOMO level of guest material 132 The energy difference (ΔE G ) and the larger the energy difference between them (i.e., especially the blue one) In the case of a guest material that exhibits luminescence, the effect of the mechanism according to one embodiment of the present invention becomes particularly pronounced.

[0106] However, the transition energy (ΔE) calculated from the absorption edge of guest material 132 G_abs ) As it decreases, the energy of the luminescence emitted by guest material 132 also decreases. This makes it difficult to obtain high-energy light, such as blue light. Nawachi, ΔE G_abs and ΔE G If the difference becomes too large, high energy like blue light will be emitted. It is difficult to obtain luminescence that has energy.

[0107] From these observations, the energy difference between the LUMO level and the HOMO level of guest material 132 is... (ΔE G ) is the transition energy (ΔE) calculated from the absorption edge of guest material 132. G_ab s Preferably, it is greater in the range of 0.4 eV to 0.8 eV, and 0.5 eV to 0 A value greater than 0.8 eV is preferable. Also, the emission exhibited by the guest material 132 Energy is ΔE G_abs Because it is equivalent to or smaller than that, guest material 132 LU The energy difference (ΔE) between the MO level and the HOMO level. G ) is the luminescence exhibited by guest material 132. Preferably, the energy is greater than the energy of 0.4eV to 0.8eV, and 0.5e A value greater than V or 0.8eV is preferable.

[0108] Furthermore, the LUMO levels of guest material 132 and organic compound 131_1 The difference is preferably 0.05 eV or more, more preferably 0.1 eV or more, and further Preferably, it is 0.2 eV or higher. Also, the HOMO level of guest material 132 and organic compound The difference between the HOMO level of compound 131_2 and the other level is preferably 0.05 eV or more, and more preferably Or more preferably 0.1 eV or higher, and more preferably 0.2 eV or higher. , electron carriers and hole carriers, organic compound 131_1 and organic compound 131_ 2 is preferable because it makes it easier to inject each of them.

[0109] Furthermore, the HOMO level of guest material 132 is higher than the HOMO level of organic compound 131_1. It is fine if it is not high, and it is fine if it is low. Also, the LUMO level of guest material 132 is organic compound 131 The LUMO level can be higher or lower than that of _2.

[0110] Furthermore, based on the relationship between the LUMO and HOMO levels described above, organic compound 131_1 and In combination with compound 131_2, one has an oxidation potential higher than the other. It is preferable that it has a reduction potential that is higher than the reduction potential of the other.

[0111] For example, organic compound 131_1 has electron transport properties, and organic compound 131_2 has hole transport properties. When it has the property, the oxidation potential of organic compound 131_1 is equal to the oxidation potential of organic compound 131_2. The reduction potential of organic compound 131_1 is higher, and the reduction potential of organic compound 131_2 is higher. A higher value is preferable. Note that oxidation potential and reduction potential are determined by cyclic voltmeters. It can be measured by tammetry (CV) method.

[0112] Furthermore, the oxidation potential of guest material 132 is higher than that of organic compound 131_2, and Furthermore, it is preferable that the reduction potential of guest material 132 is lower than that of organic compound 131_1. It seems so. By doing so, as described above, guest material 132 and organic compound 131_1 Alternatively, the reaction that forms an excited complex with organic compound 131_2 can be suppressed.

[0113] Furthermore, the combination of organic compound 131_1 and organic compound 131_2 exhibits hole transport properties. In the case of a combination of a compound that possesses electron transport properties and a compound that has electron transport properties, the mixing ratio of the two compounds... This makes it possible to easily control the carrier balance. Specifically, it has hole transport properties. Compounds: Compounds with electron transport properties = preferably in the range of 1:9 to 9:1 (by weight). Furthermore, having this configuration makes it easy to control the career balance. Furthermore, the carrier recombination region can be easily controlled.

[0114] The excited complex formed by organic compound 131_1 and organic compound 131_2 is formed by one of the organic compounds The compound has a HOMO and the other organic compound has a LUMO, therefore the HOMO and LUMO The overlap with the singlet excitation energy level is extremely small. That is, the excited complex has a triple overlap with the singlet excitation energy level. The difference with the term excitation energy level becomes smaller. Therefore, organic compound 131_1 and organic compound The excited complex formed by compound 131_2 has a triplet excitation energy level and a singlet excitation energy level. The difference from the Gee level is preferably greater than 0 eV and 0.2 eV or less.

[0115] Here, in the light-emitting layer 130, organic compound 131_1 and organic compound 131_2, Figure 2(B) shows the energy level correlation with material 132. The notation and symbols are as follows: ·Host(131_1): Host material (organic compound 131_1) ·Host(131_2): Host material (organic compound 131_2) • Guest(132): Guest material 132 (phosphorescent compound) ·S PH : S1 level of host material (organic compound 131_1) ·T PH : T1 level of host material (organic compound 131_1) ·S PG : S1 level of guest material 132 (phosphorescent compound) ·T PG : T1 level of guest material 132 (phosphorescent compound) ·S PE : S1 level of the excited complex ·T PE : T1 level of the excited complex

[0116] In a light-emitting element according to one aspect of the present invention, the light-emitting layer 130 has an organic compound 131_1 and Organic compound 131_2 forms an excited complex. The lowest singlet excited state of the excited complex. Rank (S PE ) and the lowest level of the triplet excited state of the excited complex (TPE ) are adjacent to each other This is what happens (see Figure 2(B) Route E7).

[0117] An excited complex is an excited state consisting of two types of substances, and in the case of photoexcitation, it becomes an excited state. It is formed when one substance interacts with the other substance in its ground state. And light When it returns to the ground state by emitting, the two substances that formed the excited complex also They behave as separate substances. In the case of electrical excitation, once one becomes excited, it quickly It forms an excited complex by interacting with the other. Alternatively, one produces holes and the other produces electrons. By receiving it, an excited complex can be rapidly formed. In this case, either substance Even if present, it can form an excited complex without forming an excited state on its own, thus creating a light-emitting layer. Most of the excited states at 130 can exist as excited complexes. Body excitation energy levels (S E or T E ) is a host material (organic) that forms an excited complex. Singlet excitation energy levels (S) of compound 131_1 and organic compound 131_2 PH )Yo As the excitation energy becomes lower, the excited state of the host material 131 is formed at a lower excitation energy. This makes it possible to reduce the driving voltage of the light-emitting element 150.

[0118] And the excited complex (S PE ) and (T PE The energy of both ) is used by guest material 132 The lowest level (T) of the triplet excited state of (phosphorescent compounds) PG ) Move to obtain light emission (See Figure 2(B) Route E8, E9).

[0119] Furthermore, the triplet excitation energy level (T) of the excited complex PE ) is the triplet of guest material 132. Excitation energy level (T PG ) is preferable to be higher. By doing so, the generated excitation The singlet and triplet excitation energies of the complex are given by the singlet excitation energy of the excited complex. Energy level (S PE ) and triplet excitation energy levels (T PE ) Guest material 132 The triplet excitation energy level (T PG Energy can be transferred to ).

[0120] By configuring the light-emitting layer 130 as described above, the guest material 132 (phosphorized) of the light-emitting layer 130 This makes it possible to efficiently obtain light emission from the combined material.

[0121] Furthermore, the processes of Route E7, Route E8, and Route E9 described above are as specified in this specification, etc. ExTET (Exciplex-Triplet Energy Transfer) ) is sometimes referred to as [this]. In other words, the light-emitting layer 130 is made from an excited complex and a guest material 132 There is an excitation energy supply to it. Also, in this case, T is not necessarily PE From S PE Inverse terms to High cross-efficiency is not necessary, S PE Since a high emission quantum yield from the material is not necessary, the material width A wider range of choices will be available.

[0122] The above reactions can be represented by the following general formulas (G11) to (G13).

[0123] D + +A - → (D·A) * (G11) (D·A) * +G → D+A+G * (G12) G * → G+hν (G13)

[0124] General formula (G11) is a combination of organic compound 131_1 and organic compound 131_2 where one of them is a hole. Received (D + ), the other party receives an electron (A - ) by which organic compound 131_1 and The organic compound 131_2 is excited into a complex ((D·A)) * This is a reaction that produces ). Also, generally Equation (G12) represents the excited complex ((D·A) * Energy transfer from ) to guest material 132(G) A movement occurs, and the excited state of guest material 132 (G * This is a reaction that produces ). Then, the general formula As shown in (G13), the excited guest material 132 emits light (hν).

[0125] Furthermore, in order to efficiently transfer excitation energy from the excited complex to the guest material 132, The triplet excitation energy level of the excited complex constitutes the host material that forms the excited complex. The triplet excitation energy of each organic compound (organic compound 131_1 and organic compound 131_2) It is preferable that the energy level is lower than the energy level. This allows for the triplication of the excited complex by each organic compound. This reduces the likelihood of a quench in the excitation energy, allowing for efficient energy transfer to the guest material 132. Movement occurs.

[0126] Furthermore, when the organic compound 131_2 has a strongly donor-like skeleton, it can be injected into the light-emitting layer 130. The holes that are created are more easily injected into organic compound 131_2 and more easily transported. When compound 131_1 has a highly acceptor-like skeleton, it is injected into the light-emitting layer 130. The electrons are injected into the organic compound 131_1 and become easier to transport. Compound 131_1 and organic compound 131_2 are more likely to form an excited complex.

[0127] By configuring the light-emitting layer 130 as described above, the light emitted from the guest material 132 of the light-emitting layer 130 is achieved. It can be obtained efficiently.

[0128] <Energy transfer mechanism> Next, the control of the intermolecular energy transfer process between the host material 131 and the guest material 132. Let's explain the factors. The mechanism of energy transfer between molecules is the Förster mechanism (bi Two mechanisms have been proposed: the polar-dipole interaction and the Dexter mechanism (electron exchange interaction). Here, the intermolecular energy transfer between the host material 131 and the guest material 132 is described. The process will be explained below, and the same applies when the host material 131 is an excited complex.

[0129] ≪Förster mechanism≫ In the Förster mechanism, energy transfer does not require direct contact between molecules, and the host Energy transfer occurs through the resonance phenomenon of dipole vibrations between material 131 and guest material 132. This is due to the resonance phenomenon of dipole oscillation, which transfers energy from the host material 131 to the guest material 132. The excited host material 131 returns to the ground state, and the guest material 13 returns to the ground state. 2 enters an excited state. Note that the rate constant k of the Förster mechanism is... h*→g This is shown in equation (1). .

[0130]

number

[0131] In equation (1), ν represents the frequency, and f' h (ν) is a standard for host material 131. Emission spectra (when discussing energy transfer from singlet excited states, fluorescence spectra are used) When discussing energy transfer from triplet excited states, the phosphorescent spectrum is used. ε g (ν) represents the molar extinction coefficient of guest material 132, N represents Avogadro's number, and n represents the refractive index of the medium, and R represents the intermolecular distance between the host material 131 and the guest material 132. τ represents the measured lifetime of the excited state (fluorescence lifetime or phosphorescence lifetime), and c represents the speed of light. φ is the emission quantum yield (or fluorescence quantum yield when discussing energy transfer from singlet excited states). When discussing energy transfer from triplet excited states, the phosphorescence quantum yield is expressed as K 2 teeth, A coefficient representing the orientation of the transition dipole moments of the host material 131 and the guest material 132 (from 0) 4) In the case of random orientation, K 2 = 2 / 3

[0132] Dexter Mechanism In the Dexter mechanism, the host material 131 and the guest material 132 come into contact with each other to create an orbital overlap. Approaching within effective contact distance, electrons from the excited host material 131 and the ground state guest material 13 Energy transfer occurs through the exchange of electrons with 2. Note that the rate constant k of the Dexter mechanism h*→g This is shown in equation (2).

[0133]

number

[0134] In equation (2), h is Planck's constant, and K is a constant with the dimension of energy. Here, ν represents the frequency, and f' h (ν) is the normalized luminescence of the host material 131. Pectol (When discussing energy transfer from singlet excited states, use fluorescence spectra, triplet When discussing energy transfer from an excited state, the phosphorescent spectrum is represented, and ε' g (ν) The normalized absorption spectrum of guest material 132 is shown, and L represents the effective molecular radius. R represents the intermolecular distance between the host material 131 and the guest material 132.

[0135] Here, the energy transfer efficiency φ from the host material 131 to the guest material 132 is present. ET is, number It is expressed by equation (3). k r This is the luminescence process of the host material 131 (energy from singlet excited state When discussing energy transfer, use fluorescence; when discussing energy transfer from triplet excited states, use phosphorus. This represents the velocity constant of light, k n This is related to the non-luminescent processes (thermal deactivation and intersystem crossing) of the host material 131. The rate constant is represented, and τ represents the measured lifetime of the excited state of the host material 131.

[0136]

number

[0137] From equation (3), the energy transfer efficiency φ ET In order to increase the speed of energy transfer degree constant k h*→g Increase the other competing rate constants k r +k n (=1 / τ) You'll understand that it's better if it's smaller.

[0138] ≪A concept for enhancing energy transfer≫ In energy transfer by the Förster mechanism, the energy transfer efficiency φ ET is, quantity Quantum yield φ (when discussing energy transfer from singlet excited states, use fluorescence quantum yield, triple When discussing energy transfer from excited states, a higher phosphorescence quantum yield is preferable. Emission spectrum of host material 131 (when discussing energy transfer from singlet excited state) (Fluorescence spectrum) and absorption spectrum of guest material 132 (from singlet ground state to triplet excitation) It is preferable that there is a large overlap with the absorption corresponding to the transition to the initial state. Furthermore, guest material A higher molar extinction coefficient for material 132 is also preferable. This is because the luminescence spectrum of the host material 131 is This means that the culvert and the absorption band that appears on the longest wavelength side of guest material 132 overlap.

[0139] Furthermore, in energy transfer by the Dexter mechanism, the rate constant k h*→g Make it bigger To do this, we need to consider the emission spectrum of the host material 131 (to discuss energy transfer from the singlet excited state). When discussing the fluorescence spectrum, use the fluorescence spectrum; when discussing energy transfer from the triplet excited state, use the phosphorescence spectrum. Absorption spectra of the culvert and guest material 132 (from singlet ground state to triplet excited state) A larger overlap with the absorption corresponding to the transition is desirable. Therefore, the energy transfer efficiency The optimization involves comparing the emission spectrum of the host material 131 with that of the guest material 132 at the longest wavelength end. This is achieved by the overlap of the absorption bands.

[0140] Furthermore, similar to the energy transfer from the host material 131 to the guest material 132, the excited complex The energy transfer process from to guest material 132 is also related to the Förster mechanism and the Deck Energy transfer occurs through both mechanisms in the star mechanism.

[0141] Therefore, one aspect of the present invention provides an energy transfer mechanism that can efficiently transfer energy to the guest material 132. Organic compound 131, a combination that forms an excited complex having the function of an energy donor. The present invention provides a light-emitting element having _1 and organic compound 131_2 as the host material 131. The excited complex formed by organic compound 131_1 and organic compound 131_2 is organic compound 1 Formation is possible at excitation energies lower than those of the excited states of 31_1 and organic compound 131_2 alone. This makes it possible to reduce the drive voltage in the light-emitting element 150. In addition, guest materials that act as energy acceptors from the singlet excitation energy levels of the excited complex. In order to facilitate energy transfer to the triplet excitation energy level 132, The emission spectrum of the complex and the longest wavelength (lowest energy) emission spectrum of guest material 132. It is preferable that the absorption band and the triplet excited state of guest material 132 overlap. The generation efficiency can be increased. Note that the excitation complex generated in the light-emitting layer 130 is single It is characterized by the proximity of the triplet excitation energy level to the triplet excitation energy level. Therefore, the emission spectrum of the excited complex and the longest wavelength side (lowest energy side) of guest material 132 By superimposing the absorption bands that appear, the triplet excitation energy level of the excited complex can be used to determine the guest material 1 This also makes it easier for energy transfer to the 32 triplet excitation energy levels to occur. .

[0142] <Material> Next, the details of the components of a light-emitting element according to one aspect of the present invention will be described below.

[0143] ≪Luminous layer≫ In the light-emitting layer 130, the host material 131 is the most abundant by weight, followed by the guest material 132 The (phosphorescent compound) is dispersed in the host material 131. Host material 13 of the luminescent layer 130 The T1 level of 1 (organic compound 131_1 and organic compound 131_2) is the luminescent layer 130 It is preferable that the T1 level is higher than that of the stock material (guest material 132).

[0144] As for organic compound 131_1, a material with higher electron transport capabilities than hole transport can be used. , 1 x 10 -6 cm 2 It is preferable that the material has an electron mobility of / Vs or higher. Examples of materials that readily accept electrons (materials with electron transport properties) include nitrogen-containing heteroaromatic compounds. Compounds having a π-electron-deficient heteroaromatic ring skeleton, and zinc and aluminum-based metal complexes. The body and other materials can be used. Examples of compounds having a π-electron-deficient heteroaromatic ring skeleton include , oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxa Phosphorus derivatives, dibenzoquinoxaline derivatives, phenanthroline derivatives, pyridine derivatives, Examples of compounds include bipyridine derivatives, pyrimidine derivatives, and triazine derivatives. Examples of lead and aluminum-based metal complexes include quinoline ligands, benzoquinoline ligands, and Examples include metal complexes having a xazole ligand or a thiazole ligand.

[0145] Specifically, for example, tris(8-quinolinolato)aluminum(III) (abbreviation: A lq), Tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Al mq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation) :BeBq2), bis(2-methyl-8-quinolinolate)(4-phenylphenolate) Luminium(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation) Examples include metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as Znq. In addition, bis[2-(2-benzoxazolyl)phenolate]zinc(II) Abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolate]zinc(II) Metal complexes having oxazole or thiazole ligands (abbreviated as ZnBTZ) Others can also be used. Furthermore, in addition to metal complexes, 2-(4-biphenylyl)-5 -(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD) or, 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazo [Il-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3, 4-Oxadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11) , 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)- 1,2,4-Triazole (abbreviation: TAZ), 9-[4-(4,5-diphenyl-4H- 1,2,4-Triazole-3-yl)phenyl]-9H-carbazole (abbreviation: CzT) AZ1), 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: mDBTBI) m-II), vasophenanthroline (abbreviation: BPhen), vasocuproin (abbreviation: B Heterocyclic compounds such as CP, and 2-[3-(dibenzothiophen-4-yl)phenyl] Dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-( Dibenzothiophene-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxali (Abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazole-9-I [biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDB) q) 2-[4-(3,6-diphenyl-9H-carbazole-9-yl)phenyl]di Benzo[f,h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenz[f,h]quinoxaline) Zothiophene-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDB) TPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]di Benzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2-[3-(3, 9'-bi-9H-carbazole-9-yl)phenyl]dibenzo[f,h]quinoxaline (Abbreviation: 2mCzCzPDBq), 4,6-bis[3-(phenanthrene-9-yl)f [enyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-diben Zothienyl phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6- Bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: 4,6mC) Heterocyclic compounds having a diazine skeleton such as zP2Pm, and 2-{4-[3-(N-Fe)}. Nyl-9H-carbazole-3-yl)-9H-carbazole-9-yl]phenyl}- Triazines such as 4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn) Heterocyclic compounds having a din skeleton, or 3,5-bis[3-(9H-carbazole-9-yl] )phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3-(3-pyridine) Heterocyclization of pyridine skeletons such as [zyl]phenyl]benzene (abbreviation: TmPyPB) Compound, 4,4'-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: Heteroaromatic compounds such as BzOs can also be used. Among the heterocyclic compounds mentioned above, Also, triazine skeleton, diazine (pyrimidine, pyrazine, pyridazine) skeleton, or pyr Heterocyclic compounds having a din skeleton are stable, reliable, and therefore preferable. Heterocyclic compounds containing have high electron transport properties and contribute to reducing the driving voltage. Also, poly( 2,5-Pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene- 2,7-diyl)-co-(pyridine-3,5-diyl) (abbreviation: PF-Py), poly [(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine) It is also possible to use polymer compounds such as (-6,6'-diyl) (abbreviation: PF-BPy). The substances described here are mainly 1 × 10 -6 cm 2 Objects with electron mobility of / Vs or greater It is a matter of quality. Furthermore, if the material has higher electron transport capabilities than holes, other materials can be used. That's fine too.

[0146] Organic compound 131_2 is a combination that can form an excited complex with organic compound 131_1. A combination is preferable. Specifically, such as π-electron-rich heteroaromatic ring skeletons and aromatic amine skeletons. It is preferable to have a skeleton with high donor potential. Compounds having a π-electron-rich heteroaromatic ring skeleton. The substances include dibenzothiophene derivatives, dibenzofuran derivatives, and carbazole derivatives. Which heteroaromatic compounds are mentioned? In this case, organic compound 131_1 and organic compound 13 The emission peak of the excited complex formed with 1_2 is the same as that of guest material 132 (phosphorescent compound). Multiplet MLCT (Metal to Ligand Charge Transfer) history The absorption band of the transition, more specifically, the absorption band on the longest wavelength side, is overlapped with that of organic compound 131. Select _1, organic compound 131_2, and guest material 132 (phosphorescent compound). This is preferable. This makes it possible to create a light-emitting element with dramatically improved luminous efficiency. Furthermore, when using thermally activated delayed fluorescence materials instead of phosphorescent compounds, the longest wavelength The absorption band on the side is preferably a singlet absorption band.

[0147] Furthermore, the following hole-transporting materials can be used as organic compound 131_2.

[0148] As a hole-transporting material, a material with higher hole transport capabilities than electron transport can be used, ×10 -6 cm 2 It is preferable that the material has a hole mobility of / Vs or greater. Specifically This uses aromatic amines, carbazole derivatives, aromatic hydrocarbons, stilbene derivatives, etc. This is possible. Furthermore, the hole-transporting material may be a polymer compound.

[0149] These materials with high hole transport capabilities include, specifically, aromatic amine compounds such as N, N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DT) DPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenyl Mino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl [amino]phenyl]-N,N'-diphenyl-(1,1'-biphenyl)-4,4' -Diamine (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophen) Examples include [phenyl]-N-phenylaminobenzene (abbreviation: DPA3B), etc. .

[0150] Furthermore, as a carbazole derivative, specifically, 3-[N-(4-diphenylamino Phenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1) ), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9 -Phenylcarbazole (abbreviation: PCzDPA2), 3,6-bis[N-(4-diphenyl (Aminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation) :PCzTPN2), 3-[N-(9-phenylcarbazole-3-yl)-N-phenyl Luamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N- (9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarb Zol (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcate Luvazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1) Examples include:

[0151] In addition, other carbazole derivatives include 4,4'-di(N-carbazolyl)bife Nyl (abbreviated as CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]bene Zen (abbreviation: TCPB), 9-[4-(10-phenyl-9-anthracenyl)phenyl ]-9H-carbazole (abbreviation: CzPA), 1,4-bis[4-(N-carbazol) Phenyl-2,3,5,6-tetraphenylbenzene, etc., can be used.

[0152] Furthermore, examples of aromatic hydrocarbons include 2-tert-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 Tracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenyl Enyl anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)ant Helical (abbreviated as DNA), 9,10-diphenylanthracene (abbreviated as DPaNth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 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) Chil)anthracene, 9,9'-bianthryl, 10,10'-diphenyl-9,9'- Biantryl, 10,10'-bis(2-phenylphenyl)-9,9'-biantryl ,10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9' -Biantril, Anthracene, Tetracene, Rubren, Perylene, 2, 5, 8, 11- Examples include tetra(tert-butyl)perylene. In addition, pentacene, coro Nen and other similar materials can also be used. In this way, 1 × 10 -6 cm 2 Hole mobility of / Vs or greater It is more preferable to use aromatic hydrocarbons having 14 or more carbon atoms and 42 or fewer carbon atoms. stomach.

[0153] Furthermore, aromatic hydrocarbons may have a vinyl skeleton. Examples of group hydrocarbons include 4,4'-bis(2,2-diphenylvinyl)biphenyl (Abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl] Examples include anthracene (abbreviated as DPVPA).

[0154] Also, poly(N-vinylcarbazole) (abbreviation: PVK) and poly(4-vinyltriphen Nylamine (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenyl [amino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide]( Abbreviation: PTPDMA), poly[N,N'-bis(4-butylphenyl)-N,N'-bis High molecular weight compounds such as (phenyl)benzidine (abbreviated as Poly-TPD) can also be used. can.

[0155] Furthermore, as a material with high hole transport properties, for example, 4,4'-bis[N-(1-naphthium [N-phenylamino]biphenyl (abbreviated as NPB or α-NPD) or N,N'- Bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4, 4'-Diamine (abbreviation: TPD), 4,4',4''-Tris(carbazole-9-yl) ) Triphenylamine (abbreviation: TCTA), 4,4',4''-tris[N-(1-naphtholamine) [1'-TNATA]-N-phenylaminotriphenylamine (abbreviation: 1'-TNATA), 4,4 ',4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: TDAT) A) 4,4',4''-Tris[N-(3-methylphenyl)-N-phenylamino] Triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(spiro-9,9' -bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4 -phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)trife Nylamine (abbreviation: mBPAFLP), N-(9,9-dimethyl-9H-fluorene-2) -yl)-N-{9,9-dimethyl-2-[N'-phenyl-N'-(9,9-dimethyl -9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine N (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H- Fluoren-7-yl)diphenylamine (abbreviation: DPNF), 2-[N-(4-diphenyl [Nylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPASF), 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl) Triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9- Phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBBi1B) P), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl) Triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''- (9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBN) BB), 4-phenyldiphenyl-(9-phenyl-9H-carbazole-3-yl) Min (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazole-3-yl) -N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N', N''-triphenyl-N,N',N''-tris(9-phenylcarbazole-3-I) (L)Benzene-1,3,5-triamine (abbreviation: PCA3B), N-(4-biphenyl) -N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-cal Bazole-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl) -N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-di Methyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9,9-dimethyl-N -phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl] Luolen-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl -9H-carbazole-3-yl)phenyl]spiro-9,9'-bifluoren-2-a Min (abbreviation: PCBASF), 2-[N-(9-phenylcarbazole-3-yl)-N -phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), 2,7-bi S[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9' - Bifluoren (abbreviation: DPA2SF), N-[4-(9H-carbazole-9-yl) Phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N' -Bis[4-(carbazole-9-yl)phenyl]-N,N'-diphenyl-9,9- Aromatic amine compounds such as dimethylfluorene-2,7-diamine (abbreviation: YGA2F) The following can be used. Also, 3-[4-(1-naphthyl)-phenyl]-9-phenyl Ru-9H-carbazole (abbreviation: PCPN), 3-[4-(9-phenanthril)-phenanthril [nyl]-9-phenyl-9H-carbazole (abbreviation: PCPPn), 3,3'-bis(9 -phenyl-9H-carbazole) (abbreviation: PCCP), 1,3-bis(N-carbazoli) Benzene (abbreviation: mCP), 3,6-bis(3,5-diphenylphenyl)-9-f Enylcarbazole (abbreviation: CzTP), 3,6-di(9H-carbazole-9-yl) -9-phenyl-9H-carbazole (abbreviation: PhCzGI), 2,8-di(9H-carbazole) Bazol-9-yl)-dibenzothiophene (abbreviation: Cz2DBT), 4-{3-[3- (9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran ( Abbreviation: mmDBFFLBi-II), 4,4',4''-(benzene-1,3,5-tri Il(tri(dibenzofuran)) (abbreviation: DBF3P-II), 1,3,5-tri(dibenzofuran) Zothiophene-4-yl)-benzene (abbreviation: DBT3P-II), 2,8-diphenyl -4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophone phenyl (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluorene- 9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) , 4-[3-(triphenylene-2-yl)phenyl]dibenzothiophene (abbreviation: mD Amine compounds such as BTPTp-II, carbazole compounds, thiophene compounds, and furans. By using compounds such as fluorene compounds, triphenylene compounds, and phenanthrene compounds. This is possible. Among the compounds mentioned above, pyrrole skeleton, furan skeleton, thiophene skeleton, and aromatic Compounds having a fragrance amine skeleton are stable, reliable, and therefore preferable. Compounds possessing this property exhibit high hole transportability and contribute to reducing the driving voltage.

[0156] Guest material 132 (phosphorescent compound) can be iridium, rhodium, or platinum-based. Examples include organometallic complexes or metal complexes, among which organoiridium complexes, for example, iridium Um-based orthometallic complexes are preferred. 4H-triazo is a suitable ligand for orthometallation. 1H-triazole ligand, 1H-triazole ligand, imidazole ligand, pyridine ligand, pyrimi Examples include din ligands, pyrazine ligands, or isoquinoline ligands. Metal complexes Examples include platinum complexes containing porphyrin ligands.

[0157] Additionally, as guest material 132 (phosphorescent compound), the LUMO of organic compound 131_1 is used. It has a LUMO level higher than the level of organic compound 131_2 and a HOM level lower than the HOMO level of organic compound 131_2. Organic compound 131_1, organic compound 131_2, and guest material to have an O level. It is preferable to select 132 (phosphorescent compound). This results in high and low luminescence efficiency. It can be a light-emitting element driven by voltage.

[0158] Examples of substances that have a blue or green emission peak include tris{2-[5-(2 -methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazo [Ir-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: Ir(mpp) tz-dmp)3), Tris(5-methyl-3,4-diphenyl-4H-1,2,4-) Ryasolato) Iridium(III) (abbreviation: Ir(Mptz)3), Tris[4-(3- [Biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato] Lydium(III) (abbreviation: Ir(iPrptz-3b)3), Tris[3-(5-Bif [Phenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridi Um(III) (abbreviation: Ir(iPr5btz)3), a 4H-triazole skeleton organometallic iridium complexes having, or tris[3-methyl-1-(2-methylphenyl) -5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: Ir (Mptz1-mp)3), Tris(1-methyl-5-phenyl-3-propyl-1H- 1,2,4-Triazolat) Iridium(III) (Abbreviation: Ir(Prptz1-Me) 3) Organometallic iridium complexes having a 1H-triazole skeleton, or fac-tri S[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole] Rydium(III) (abbreviation: Ir(iPrpmi)3), Tris[3-(2,6-dimethyl Iridium (I)-7-methylimidazo[1,2-f]phenantridinato]iridium II) (abbreviation: Ir(dmpimpt-Me)3) has an imidazole skeleton iridium metal complexes and bis[2-(4',6'-difluorophenyl)pyridinate- N,C 2’ Iridium(III) tetrakis(1-pyrazolyl) borate (abbreviation: FI) r6), bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ ] Iri Dium(III) picolinate (abbreviation: Firpic), bis{2-[3',5'-bis (trifluoromethyl)phenyl]pyridinate-N,C 2’ Iridium(III) pico Rinart (abbreviation: Ir(CF3ppy)2(pic)), Bis[2-(4',6'-Jif Luorophenyl)pyridinate-N,C 2’ Iridium(III) acetylacetonate (abbreviation: Fir(acac)) contains a phenylpyridine derivative having an electron-withdrawing group. Examples include organometallic iridium complexes used as ligands. Among those mentioned above, 4H-triazole is one example. Nitrogen-containing five-membered heterocyclic skeletons such as the 1H-triazole skeleton and the imidazole skeleton The organometallic iridium complex possesses high triplet excitation energy, reliability, and luminescence efficiency. It is particularly preferable because it excels in this area.

[0159] Furthermore, examples of substances that have a green or yellow emission peak include tris(4-methyl Iridium(III) (abbreviation: Ir(mppm)3), 6-phenylpyrimidinato Tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: I r(tBuppm)3), (acetylacetonate)bis(6-methyl-4-phenylpyryl) Iridium(III) (abbreviation: Ir(mppm)2(acac)), (acetyl Luacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium III) (Abbreviation: Ir(tBuppm)2(acac)), (acetylacetonato)bis [4-(2-norbornyl)-6-phenylpyrimidinato]iridium(III) (abbreviation) :Ir(nbppm)2(acac)),(acetylacetonato)bis[5-methyl-6 -(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: Ir(mpmppm)2(acac)), (acetylacetonato)bis{4,6-dimethicone} Lu-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl- κC} Iridium(III) (abbreviation: Ir(dmppm-dmp)2(acac)), ( Acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III)( Abbreviation: Organometallic irritants with a pyrimidine skeleton, such as Ir(dppm)2(acac) Dium complexes, and (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazine Iridium(III) (abbreviation: Ir(mppr-Me)2(acac)), (acetyl Luacetonato)bis(5-isopropyl-3-methyl-2-phenylpyradinato)iridi Pyrazine bones like Um(III) (abbreviation: Ir(mppr-iPr)2(acac)) iridium organometallic complexes with a specific classification, and tris(2-phenylpyridinato-N,C) 2’ ) Iridium(III) (abbreviation: Ir(ppy)3), bis(2-phenylpyridinate-N) ,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(ppy)2(ac) ac)), bis(benzo[h]quinolinate)iridium(III)acetylacetonate (Abbreviation: Ir(bzq)2(acac)), Tris(benzo[h]quinolinato)iridiu Mu(III) (abbreviation: Ir(bzq)3), Tris(2-phenylquinolinato-N,C) 2 ’ ) Iridium(III) (abbreviation: Ir(pq)3), bis(2-phenylquinolinazole- N,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(pq)2(ac) Organometallic iridium complexes having a pyridine skeleton, such as ac)), and bis(2,4-diph Enyl-1,3-oxazolato-N,C 2’ Iridium(III) Acetylaceton (abbreviation: Ir(dpo)2(acac)), bis{2-[4'-(perfluorophenicol) [Phenyl]pyridinate-N,C 2’ Iridium(III) acetylacetonate ( Abbreviation: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzothiazolat -N,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(bt)2(a) In addition to organometallic iridium complexes such as CAC, there are also tris(acetylacetonate)(monophenate). Nanthroline terbium(III) (abbreviation: Tb(acac)3(Phen)) Examples include rare earth metal complexes. Among those mentioned above, organometallic ylids having a pyrimidine skeleton are particularly noteworthy. Dium complexes are particularly preferred because they exhibit outstanding reliability and luminescence efficiency.

[0160] Furthermore, examples of substances that have a yellow or red emission peak include (diisobutyryl Methanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(II) I) (abbreviation: Ir(5mdppm)2(dibm)), bis[4,6-bis(3-methyl [Phenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: Ir (5 mdppm)2(dpm)), bis[4,6-di(naphthalene-1-yl)pyrimid Nat] (dipivaloylmethanato) Iridium(III) (Abbreviation: Ir(d1npm)2) Organometallic iridium complexes having a pyrimidine skeleton such as dpm, and (acetylacet Tonato)bis(2,3,5-triphenylpyradinato)iridium(III) (abbreviation: I r(tppr)2(acac)), bis(2,3,5-triphenylpyrazinate)(dipy Valoylmethanato) Iridium(III) (abbreviation: Ir(tppr)2(dpm)), ( Acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato] A pyrazine skeleton like lysium(III) (abbreviation: Ir(Fdpq)2(acac)) The organometallic iridium complexes and tris(1-phenylisoquinolinato-N,C) 2’ ) Iridium(III) (abbreviation: Ir(piq)3), bis(1-phenylisoquinolinate) -N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(piq)2( In addition to organometallic iridium complexes with a pyridine skeleton such as acac), 2, 3, 7, 8,12,13,17,18-Octaethyl-21H,23H-Porphyrin Platinum(II) Platinum complexes such as (abbreviation: PtOEP) and tris(1,3-diphenyl-1,3-p Europium(III) (Abbreviation: Eu(DB) M)3(Phen)), Tris[1-(2-tenoyl)-3,3,3-trifluoroacetate Tonato (monophenanthroline) europium(III) (abbreviation: Eu(TTA)3) Examples include rare earth metal complexes such as Phen). Among those mentioned above, the pyrimidine skeleton The organometallic iridium complex possessed is particularly preferred because of its outstanding reliability and luminescence efficiency. Furthermore, organometallic iridium complexes having a pyrazine skeleton can produce a red luminescence with good chromaticity. It can be done.

[0161] The light-emitting material included in the light-emitting layer 130 is capable of converting triplet excitation energy into light emission. Any material will do. A material that can convert the triplet excitation energy into light emission is phosphorescent. In addition to the compound, there is thermally activated delayed fluorescence. Examples include phosphorescent (TADF) materials. Where the term "compound" is used, it may be interpreted as "thermally activated delayed fluorescence material." Thermally activated delayed fluorescence materials are materials that have a triplet excitation energy level and a singlet excitation energy level. The difference is small, and the energy is converted from the triplet excited state to the singlet excited state by reverse intersystem crossing. It is a material that has the function of doing so. Therefore, the triplet excited state can be activated with a small amount of thermal energy. Upconversion to a singlet excited state (reverse intersystem crossing) is possible, and from the singlet excited state It can efficiently exhibit light (fluorescence). Furthermore, thermally activated delayed fluorescence can be obtained efficiently. The condition is that the energy difference between the triplet excitation energy level and the singlet excitation energy level is Preferably greater than 0 eV and 0.2 eV or less, more preferably greater than 0 eV and 0.1 eV. One example is that it is below eV.

[0162] When a thermally activated delayed fluorescence material is composed of only one type of material, for example, the following materials can be used. It is possible.

[0163] First, there are fullerenes and their derivatives, acridine derivatives such as proflavin, and eosin. It can be produced. Also, magnesium (Mg), zinc (Zn), cadmium (Cd), tin (S) n) Metals containing platinum (Pt), indium (In), or palladium (Pd), etc. Examples include metal-containing porphyrins. For example, protoporph Fluorine-tin fluoride complex (SnF2(Proto IX)), mesoporphyrin-fluoride Tin complex (SnF2(Meso IX)), hematoporphyrin-tin fluoride complex (Sn F2 (Hemato IX), coproporphyrin tetramethyl ester - tin fluoride Complex (SnF2(Copro III-4Me)), octaethylporphyrin-fluoride Tin complex (SnF2(OEP)), Ethioporphyrin-tin fluoride complex (SnF2(E Examples include tio I)) and octaethylporphyrin-platinum chloride complex (PtCl2OEP). It can be done.

[0164] Furthermore, as a thermally activated delayed fluorescence material composed of one type of material, a π-electron-rich complex atom is an example. Heterocyclic compounds having aromatic rings and π-electron-deficient heteroaromatic rings can also be used. Specifically is 2-(biphenyl-4-yl)-4,6-bis(12-phenylindoro[2,3- a)Carbazole-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol [9-yl]phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PC) CzPTzn), 2-[4-(10H-phenoxazine-10-yl)phenyl]-4, 6-Diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5- Phenyl-5,10-dihydrophenazine-10-yl)phenyl]-4,5-diphenyl Lu-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl- 9H-acridine-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] Examples include -9,9'-anthracene]-10'-one (abbreviated as ACRSA). Because the cyclic compounds have π-electron-rich heteroaromatic rings and π-electron-deficient heteroaromatic rings, High transportability and hole transportability are desirable. In particular, a skeleton having a π-electron-deficient heteroaromatic ring is preferred. Among these, diazine skeletons (pyrimidine skeletons, pyrazine skeletons, pyridazine skeletons), or tri The azine skeleton is preferred because it is stable and reliable. Furthermore, the π-electron-rich heteroaromatic ring is also preferred. Among the skeletons it possesses, the acridine skeleton, phenoxazine skeleton, thiophene skeleton, and furan skeleton are particularly noteworthy. The pyrrole skeleton is stable and reliable, therefore any of the skeletons can be selected. It is preferable to have one or more of these. The pyrrole skeleton is indole. The skeleton, the carbazole skeleton, and 3-(9-phenyl-9H-carbazole-3-yl)- A 9H-carbazole skeleton is particularly preferred. Note that π-electron-rich heteroaromatic rings and π-electron-deficient rings are also preferred. Substances directly bonded to a type of heteroaromatic ring exhibit both donor and π-electron-deficient properties for π-electron-rich heteroaromatic rings. Both the acceptor properties of the complex aromatic ring are strong, and the singlet excitation energy level and the triplet excitation energy This is particularly preferable because it reduces the difference in energy levels.

[0165] The light-emitting layer 130 can also be composed of two or more layers. For example, the first When the first light-emitting layer and the second light-emitting layer are stacked in order from the hole transport layer side to form the light-emitting layer 130, A material having hole transport properties is used as the host material for the first light-emitting layer, and the host material for the second light-emitting layer This includes configurations that use materials with electron transport properties. Also, the first light-emitting layer and the second light-emitting layer The light-emitting material in the light layer may be the same material or different materials, and the same color light-emitting material may be emitted. Even if a material has the function of emitting light, it is a material that has the function of emitting light of different colors. It is also acceptable to use two light-emitting layers, each containing a light-emitting material that exhibits different colors of light emission. By using each of them, multiple light sources can be obtained simultaneously. In particular, the two light-emitting layers exhibit It is preferable to select the light-emitting material used in each light-emitting layer so that it becomes white due to the light emission.

[0166] Furthermore, in the light-emitting layer 130, materials other than the host material 131 and the guest material 132 are used. It's okay to have it.

[0167] The light-emitting layer 130 is produced by vapor deposition (including vacuum deposition), inkjet, coating, etc. It can be formed by methods such as labia printing. In addition to the materials mentioned above, quantum dots, etc. Even if it has an inorganic compound or polymer compound (oligomer, dendrimer, polymer, etc.) good.

[0168] ≪Hole Injection Layer≫ The hole injection layer 111 is a hole injection layer that receives holes from one of the pair of electrodes (electrode 101 or electrode 102). It has the function of promoting hole injection by reducing the injection barrier, for example, transition metal oxides, f It is formed by tarocyanine derivatives or aromatic amines, etc. Transition metal oxides and For example, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide Examples include manganese oxides. Phthalocyanine derivatives include phthalocyanine and Examples include metal phthalocyanines. Aromatic amines include benzidine derivatives and phenyl Examples include lendiamine derivatives. Polymer compounds such as polythiophene and polyaniline. It is also possible to use substances, for example, self-doped polythiophenes such as poly(ethylenedi(ethylenedi) Typical examples include oxythiophene / poly(styrene sulfonic acid).

[0169] As the hole injection layer 111, a hole transport material and a material that exhibits electron-accepting properties in relation to it are combined. A layer containing composite material can also be used. Alternatively, a layer containing an electron-accepting material and a positive A lamination of layers containing pore-transporting material may also be used. Between these materials, a steady state or electrical current may be maintained. Charge transfer is possible in the presence of an electron barrier. Examples of materials exhibiting electron-accepting properties include Kinojimeta. Organic acceptors such as chloranil derivatives and hexaazatriphenylene derivatives We can list the following: Specifically, 7,7,8,8-tetracyano-2,3,5,6- Tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7, 10,11-Hexacyano-1,4,5,8,9,12-Hexazatriphenylene (abbreviated) These are compounds that have electron-withdrawing groups (halogen groups or cyano groups), such as HAT-CN. Furthermore, transition metal oxides, such as oxides of Group 4 to Group 8 metals, can be used. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, acid These include tungsten oxide, manganese oxide, and rhenium oxide. Among them, molybdenum oxide is airborne. Among them, it is preferable because it is stable, has low hygroscopicity, and is easy to handle.

[0170] As a hole-transporting material, a material with higher hole transport capabilities than electron transport can be used, ×10 -6 cm 2 It is preferable that the material has a hole mobility of / Vs or greater. Specifically Aromatic amines and calcine are listed as hole transport materials that can be used in the light-emitting layer 130. Basol derivatives, aromatic hydrocarbons, stilbene derivatives, etc., can be used. The hole-transporting material may be a polymer compound.

[0171] ≪Hole transport layer≫ The hole transport layer 112 is a layer containing a hole transportable material, and is an example of the material used for the hole injection layer 111. The hole transport material shown can be used. The hole transport layer 112 is in the hole injection layer 111. Because it has the function of transporting the injected holes to the light-emitting layer 130, the HOM of the hole injection layer 111 It is preferable to have the same or close HOMO level as the O level.

[0172] Also, 1 × 10 -6 cm 2 It is preferable that the substance has a hole mobility of / Vs or higher. However, other materials may be used as long as they have higher hole transport capabilities than electron transport. Furthermore, the layer containing the material with high hole transport properties may be a single layer, or a double layer consisting of the aforementioned material. You may stack more than this amount.

[0173] ≪Electron transport layer≫ The electron transport layer 118 passes through the electron injection layer 119 to the other of the pair of electrodes (electrode 101 or electron It has the function of transporting electrons injected from pole 102) to the light-emitting layer 130. Electron transport material For this purpose, materials with higher electron transport capabilities than holes can be used, resulting in 1 × 10⁻⁶ -6 cm 2 It is preferable that the material has an electron mobility of / Vs or higher. Examples of materials (materials with electron transport properties) include π-electron-deficient types such as nitrogen-containing heteroaromatic compounds. Hetero-aromatic compounds and metal complexes can be used. Specifically, they can be used in the light-emitting layer 130. The electron transport materials listed as capable of this include quinoline ligands, benzoquinoline ligands, and oxalool. Examples include metal complexes having a zole ligand or a thiazole ligand. Also, oxal Diazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives Body, dibenzoquinoxaline derivatives, phenanthroline derivatives, pyridine derivatives, bipyrid Examples include derivatives of ions, pyrimidine derivatives, and triazine derivatives. Also, 1 × 10 -6 cm2 It is preferable that the material has an electron mobility of / Vs or higher. Any material with high electron transport capabilities may be used as the electron transport layer, other than those mentioned above. Furthermore, the electron transport layer 118 can be a single layer, or two or more layers made of the above material can be stacked. good.

[0174] Furthermore, a layer for controlling the movement of electron carriers is provided between the electron transport layer 118 and the light-emitting layer 130. It is also acceptable to use materials with high electron transport properties, as described above, and materials with high electron trapping properties. A layer to which a small amount of is added, thereby suppressing the movement of electron carriers, carrier balance This makes it possible to adjust the balance. In this configuration, electrons penetrate the light-emitting layer. This has a significant effect in suppressing problems that may arise as a result (for example, a decrease in the lifespan of the device).

[0175] ≪Electron injection layer≫ The electron injection layer 119 promotes electron injection by reducing the electron injection barrier from the electrode 102. It has the function of being, for example, Group 1 metals, Group 2 metals, or their oxides and halides. Carbonates and the like can be used. In addition, the electron transport material shown above and the electron transport material therefor Composite materials exhibiting electron-donating properties can also be used. Examples of electron-donating materials include: Examples include Group 1 metals, Group 2 metals, or oxides thereof. Specifically These are lithium fluoride (LiF), sodium fluoride (NaF), and cesium fluoride (CsF). ), calcium fluoride (CaF2), lithium oxide (LiO2) x ) and other alkali metals Alkaline earth metals, or compounds thereof can be used. Also, fluoride Rare earth metal compounds such as bium (ErF3) can be used. Furthermore, electron injection layers can be used. An electride may be used in 119. For example, calcium Examples include substances obtained by adding a high concentration of electrons to a mixed oxide of aluminum and luminum. The injection layer 119 may be made of a material that can be used in the electron transport layer 118.

[0176] Furthermore, the electron injection layer 119 is a composite made by mixing an organic compound and an electron donor. Materials may be used. Such composite materials are created when electrons are released from the organic compound by an electron donor. Therefore, it exhibits excellent electron injection and electron transport properties. In this case, as an organic compound... Preferably, the material is one that is excellent at transporting the generated electrons, specifically, for example, the material described above. The electron transport layer 118 can be composed of materials (such as metal complexes or heteroaromatic compounds). The electron donor can be any substance that exhibits electron-donating properties towards organic compounds. Alkali metals, alkaline earth metals, and rare earth metals are preferred, as are lithium and sodium. Examples include cesium, magnesium, calcium, erbium, and ytterbium. Furthermore, alkali metal oxides and alkaline earth metal oxides are preferred, as are lithium oxides and calcium oxides. Examples include sium oxide and barium oxide. Also, Lewis plates such as magnesium oxide. Bases can also be used. Additionally, organic compounds such as tetrathiafulvalene (abbreviated as TTF) can be used. Objects can also be used.

[0177] Furthermore, the above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer, and electron injection layer are, These methods include vapor deposition (including vacuum deposition), inkjet printing, coating, and gravure printing. It can be formed by the above-mentioned method. In addition, the light-emitting layer, hole injection layer, hole transport layer, electron In addition to the materials mentioned above, the transport layer and electron injection layer also contain inorganic compounds such as quantum dots and high-molecular-weight materials. Sub-compounds (oligomers, dendrimers, polymers, etc.) may also be used.

[0178] Quantum dots include colloidal quantum dots, alloy quantum dots, and core-shell quantum dots. You may also use type quantum dots, core quantum dots, etc. Also, groups 2, 16, and 13 Includes element groups of Group 15, Groups 13 and 17, Groups 11 and 17, or Groups 14 and 15. Quantum dots may be used. Alternatively, cadmium (Cd), selenium (Se), zinc (Zn) may be used. ), sulfur (S), phosphorus (P), indium (In), tellurium (Te), lead (Pb), gallium Quantum dots containing elements such as um (Ga), arsenic (As), and aluminum (Al) are used. It's okay to be there.

[0179] ≪A pair of electrodes≫ Electrodes 101 and 102 function as the anode or cathode of the light-emitting element. 101 and electrode 102 are made of metals, alloys, conductive compounds, and mixtures or laminates thereof. It can be formed using [a specific method / tool].

[0180] Either electrode 101 or electrode 102 is formed by a conductive material having the function of reflecting light. Preferably, this is done. The conductive material is aluminum (Al) or an Al-containing alloy. Examples include gold. Alloys containing Al include Al and L (where L is titanium (Ti) and neodymium). Includes (one or more of Nd, Ni, and La) Examples include alloys containing Al and Ti, or Al, Ni, and La. Aluminum has low resistance and high light reflectivity. Also, aluminum is found in the Earth's crust. Because it is abundant and inexpensive, using aluminum reduces the cost of manufacturing light-emitting devices. It can reduce the amount of silver (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), nickel, copper (Cu), palladium (Pd), iridium (Ir ), or alloys containing one or more gold (Au) may be used. Examples of alloys include alloys containing silver, palladium, and copper, alloys containing silver and copper, and alloys containing silver and magnesium. Alloys containing nesium, alloys containing silver and nickel, alloys containing silver and gold, and alloys containing silver and ytterbium Examples include alloys containing tungsten, chromium (Cr), and molybdenum (Mo). ), transition metals such as copper and titanium can be used.

[0181] Furthermore, the light emitted from the light-emitting layer passes through one or both of electrodes 101 and 102. And it is removed. Therefore, at least one of electrode 101 and electrode 102 transmits light. Preferably, it is formed from a conductive material having the function of being visible. The light transmittance is 40% or more and 100% or less, preferably 60% or more and 100% or less, and That resistivity is 1 × 10⁻⁶ -2 Examples include conductive materials with a conductivity of Ω·cm or less.

[0182] Furthermore, electrodes 101 and 102 have the function of transmitting light and the function of reflecting light. It may be formed from a conductive material having a visible light reflectance of 20. The resistivity is between % and 80%, preferably between 40% and 70%, and its resistivity is 1 × 10⁻⁶. -2 Examples of conductive materials include those with a conductivity of Ω·cm or less. For example, conductive metals, alloys, and conductive materials. It can be formed using one or more types of chemical compounds. Specifically, for example, Indium tin oxide (ITO), silicon, or silicon oxide Indium tin oxide (abbreviated as ITSO), indium oxide-zinc oxide (Indi Indium-tin oxide containing titanium (indium zinc oxide), indium Metals such as indium oxide containing titanium oxide, tungsten oxide, and zinc oxide. Oxides can be used. Also, the degree to which light is transmitted (preferably 1 nm to 30 nm) A thin metal film with a thickness of m or less can be used. Examples of metals include Ag, or Alloys such as Ag and Al, Ag and Mg, Ag and Au, and Ag and Yb can be used.

[0183] In this specification, etc., a material having the function of transmitting light is defined as a material having the function of transmitting visible light. Any material that has and is conductive is acceptable, for example, ITO as described above. In addition to oxide conductors, the collection includes oxide semiconductors or organic conductors containing organic materials. Examples of organic conductors include those obtained by mixing an organic compound with an electron donor. Examples include composite materials, such as composite materials formed by mixing organic compounds with electron acceptors. It is possible to use inorganic carbon-based materials such as graphene. Preferably, the ratio is 1 × 10⁻⁶. 5 Ω·cm or less, more preferably 1 × 10⁻⁶ 4 Ω·cm The following applies:

[0184] Furthermore, by stacking multiple of the above materials, one of the electrodes 101 and 102 can be made They may form both.

[0185] Furthermore, in order to improve the light extraction efficiency, the electrode having a light-transmitting function is brought into contact with the A material with a refractive index higher than that of the electrode may be formed. Such a material may transmit visible light. Any material that has the function of being conductive is acceptable, and even if it is a conductive material, it does not have that function. Other options include oxide conductors, oxide semiconductors, and organic materials. Examples of organic materials include the light-emitting layer, hole injection layer, hole transport layer, electron transport layer, or electric Examples of materials used in the sub-injection layer include inorganic carbon-based materials and metals that are transparent to light. Thin films can also be used, and multiple layers of several nanometers to tens of nanometers in thickness may be stacked.

[0186] When electrode 101 or electrode 102 functions as a cathode, the work function is small. It is preferable that the material has a (3.8 eV or less) energy. For example, it is preferable that it has elements from Group 1 or Group 2 of the periodic table. Elements belonging to the group (alkali metals such as lithium, sodium, and cesium, calcium, stoichiometric compounds) Alkaline earth metals such as rontium, magnesium, etc., and alloys containing these elements (for example, Rare earth metals such as Ag and Mg, Al and Li, europium (Eu), Yb, and these rare earths Metal alloys, aluminum alloys, silver alloys, etc., can be used.

[0187] Furthermore, when electrode 101 or electrode 102 is used as the anode, the work function is large (4. It is preferable to use a material with a voltage of 0 eV or higher.

[0188] Furthermore, electrodes 101 and 102 are made of a conductive material that has the function of reflecting light and a material that transmits light. It may also be laminated with a conductive material having a function of passing through. In that case, electrode 101 and electrode 1 02 is designed to resonate with the desired light from each light-emitting layer, thereby intensifying the light of that wavelength. This is preferable because it can have a function to adjust the optical distance.

[0189] The methods for forming the film of electrodes 101 and 102 include sputtering, vapor deposition, printing, and coating. MBE (Molecular Beam Epitaxy), CVD, Pulse Ray The deposition method, ALD (Atomic Layer Deposition), etc., are used as appropriate. It is possible.

[0190] Circuit board Furthermore, a light-emitting element according to one aspect of the present invention is placed on a substrate made of glass, plastic, or the like. It is fine to manufacture it. In terms of the order in which it is manufactured on the substrate, it is fine to stack them in order from the electrode 101 side. You may also stack them sequentially starting from pole 102.

[0191] Examples of substrates on which a light-emitting element according to one aspect of the present invention can be formed include glass and quartz. , or plastic can be used. A flexible substrate may also be used. A substrate is a flexible substrate that can be bent, for example, polycarbonate Examples include plastic substrates made of nate, polyarylate, etc. Also, films, Inorganic vapor-deposited films can also be used. Note: The manufacturing process for light-emitting elements and optical elements. Anything other than these that functions as a support in the context is acceptable. Alternatively, Any device that has the function of protecting optical elements and other optical components is acceptable.

[0192] For example, in the present invention, a light-emitting element can be formed using various substrates. The type of substrate is not particularly limited. One example of such a substrate is a semiconductor substrate (for example) (e.g., single crystal substrate or silicon substrate), SOI substrate, glass substrate, quartz substrate, plastic substrate Plates, metal substrates, stainless steel substrates, substrates having stainless steel foil, Tungsten substrate, substrate with tungsten foil, flexible substrate, laminated film , cellulose nanofibers (CNF) containing fibrous materials, paper, or base films, etc. Yes, there are. Examples of glass substrates include barium borosilicate glass and aluminoborosilicate glass. Examples include soda-lime glass or flexible substrates, laminated films, and substrate films. Examples of materials include the following: For example, polyethylene terephthalate (PE T), polyethylene naphthalate (PEN), polyethersulfone (PES), poly There are plastics such as transfluoroethylene (PTFE). Or, as an example... Examples include resins such as acrylic. Alternatively, polypropylene, polyester, etc. Examples include polyvinyl fluoride or polyvinyl chloride. Alternatively, as an example, Examples include amides, polyimides, aramids, epoxy, inorganic vapor-deposited films, and papers.

[0193] Alternatively, a flexible substrate may be used as the substrate, and the light-emitting element may be formed directly on the flexible substrate. Alternatively, a release layer may be provided between the substrate and the light-emitting element. The release layer is provided on top of the light-emitting element. After partially or completely completing the child component, it is separated from the circuit board and used for transferring it to another circuit board. This allows for the transfer of light-emitting elements to substrates with poor heat resistance or flexible substrates. Oh, the aforementioned delamination layer has, for example, a laminated inorganic film structure of a tungsten film and a silicon oxide film. Configurations such as the one shown, or a configuration in which a resin film such as polyimide is formed on the substrate, can be used.

[0194] In other words, a light-emitting element is formed using one substrate, and then the light-emitting element is transferred to another substrate. The light-emitting element may be placed on a different substrate. An example of a substrate on which the light-emitting element is placed is the above In addition to the substrates mentioned above, there are also cellophane substrates, stone substrates, wood substrates, and cloth substrates (natural fibers (silk, cotton, Hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate) (including t, cupro, rayon, recycled polyester, etc.), leather substrate, or rubber substrate. These substrates can be used to create light-emitting elements that are less prone to breakage and have high heat resistance. This can be a child, a lightweight light-emitting element, or a thinned light-emitting element.

[0195] Furthermore, a field-effect transistor (FET), for example, is formed on the aforementioned substrate, and the FET and The light-emitting element 150 may be fabricated on electrically connected electrodes. This allows the FET to This allows us to create an active-matrix type display device that controls the driving of the light-emitting element 150.

[0196] In this embodiment, one aspect of the present invention has been described. Or, other embodiments may be described. In this context, one aspect of the present invention will be described. However, this aspect of the present invention is not limited to these. Not done. In other words, various aspects of the invention are described in this embodiment and other embodiments. Therefore, one aspect of the present invention is not limited to a specific aspect. For example, one aspect of the present invention While an example of its application to a light-emitting element has been shown, one aspect of the present invention is not limited thereto. For example, depending on the circumstances, one aspect of the present invention may be suitable for a light-emitting element. It is not necessary to use it. Alternatively, for example, in one aspect of the present invention, a first organic compound and a second Organic compounds and guest compounds that have the function of converting triplet excitation energy into light emission. The material has, and the LUMO level of the first organic compound is the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than that of the second organic compound. Although examples of cases have been shown, the present invention is not limited thereto. In some cases, Depending on the circumstances, in one aspect of the present invention, for example, the LUMO level of the first organic compound is The LUMO level of the second organic compound does not have to be lower than that of the first organic compound. The HOMO level does not have to be lower than the HOMO level of the second organic compound. Or, for example, In one aspect of the present invention, the first organic compound and the second organic compound form an excited complex. While examples of such cases have been shown, the present invention is not limited thereto. In some cases, Depending on the circumstances, in one aspect of the present invention, for example, a first organic compound and a second organic compound The excited complex does not need to be formed. Alternatively, for example, in one aspect of the present invention, a guest material The LUMO level of the material is higher than that of the first organic compound, and the HOMO level of the guest material is higher. An example was shown where the level is lower than the HOMO level of the second organic compound, but this is one aspect of the present invention. This is not limited to the present invention. In some cases, or depending on the circumstances, one aspect of the present invention may be For example, the LUMO level of the guest material is not higher than the LUMO level of the first organic compound. Alternatively, the HOMO level of the guest material may be the same as the HOMO level of the second organic compound. It doesn't have to be that low.

[0197] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0198] (Embodiment 2) In this embodiment, a new compound that can be suitably used in a light-emitting element according to one aspect of the present invention I will explain the item below.

[0199] A compound according to one aspect of the present invention is an iridium complex having a nitrogen-containing five-membered heterocyclic skeleton as a ligand. The nitrogen-containing five-membered heterocyclic skeleton has substituents including at least a cyano group. Nitrogen-containing five-membered heterocyclic skeletons such as zole and triazole skeletons have high triplet excitation energies. - It has energy levels, but its electron-accepting ability is lower compared to nitrogen-containing six-membered heterocyclic skeletons. Therefore, nitrogen-containing Iridium complexes with a five-membered heterocyclic skeleton as a ligand have high LUMO levels and electron carriers A is difficult to inject. However, the iridium complex of one aspect of the present invention has at least S Because it has substituents including an ano group, the strong electron-withdrawing properties of the cyano group cause the LUMO level and The HOMO level decreases. Therefore, by using this iridium complex in a light-emitting device, It is possible to create light-emitting devices with good luminescence efficiency. Furthermore, this iridium complex has high 3 Because it has a multiplet excitation energy level, the iridium complex can be used in a light-emitting device. This makes it possible to create a light-emitting element that exhibits a blue light with good luminescence efficiency. Since iridium complexes have good resistance to repeated oxidation and reduction, the iridium complex By using this in the light-emitting element, it is possible to create a light-emitting element with a good operating life. As described above, by using an iridium complex according to one aspect of the present invention in a light-emitting device, excellent luminescence characteristics can be achieved. It is possible to fabricate high-performance light-emitting elements.

[0200] Furthermore, one embodiment of the present invention is an aryl compound containing a cyano group on a nitrogen-containing five-membered heterocyclic skeleton. It is an iridium complex having a ligand to which a group is attached. When synthesizing this ligand, high purity is required. Because it is easy to synthesize, it is possible to suppress degradation due to impurities. Oh, from the standpoint of stability and reliability of device characteristics, cyano groups bonded to a nitrogen-containing five-membered heterocyclic skeleton The aryl group containing is preferably 6 to 13 carbon atoms. In this case, the aryl group Because the complex can be vacuum deposited at relatively low temperatures, degradation such as thermal decomposition during deposition is less likely to occur.

[0201] Furthermore, the nitrogen atom in the nitrogen-containing five-membered heterocyclic skeleton bonds with the cyano group via the arylene group. Iridium complexes with combined ligands can maintain high triplet excitation energy levels. Therefore, it can be suitably used in light-emitting elements that exhibit high-energy light, such as blue light. It can do so. Furthermore, it exhibits high-energy luminescence, such as blue light, compared to cases without a cyano group. Furthermore, highly efficient light-emitting elements can be obtained. This allows for the creation of reliable light-emitting elements that exhibit high-energy light, such as blue light. It also has the characteristic of being able to do so. Furthermore, between the above nitrogen-containing five-membered heterocyclic skeleton and the cyano group, It is preferable that the bond is formed via an arylene group such as a nilen group.

[0202] Furthermore, if the number of carbon atoms in the arylene group is between 6 and 13, the iridium complex is comparative Because it is a low molecular weight compound, it is suitable for vacuum deposition (vacuum deposition can be performed at relatively low temperatures). It becomes a substance. Also, generally speaking, if the molecular weight is low, the heat resistance after film formation is often poor, but Because this iridium complex has multiple ligands, it has sufficient heat resistance even if the molecular weight of the ligands is low. It has the advantage of ensuring sexual intercourse.

[0203] In other words, the iridium complex, in addition to the ease of deposition and electrochemical stability mentioned above, It also has the characteristic of having a high triplet excitation energy level. Therefore, in light-emitting devices... It is preferable to use the iridium complex as the guest material for the luminescent layer. In particular, it is more preferable to use it as a guest material for blue light-emitting elements.

[0204] <Example 1 of iridium complexes> The iridium complex described above is an iridium complex represented by the following general formula (G1).

[0205] [ka]

[0206] In the above general formula (G1), Ar 1 and Ar 2 Each of these independently has 6 to 1 carbon atoms. This represents a substituted or unsubstituted aryl group with 3 carbon atoms. Examples of aryl groups with 6 to 13 carbon atoms include: Examples include phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups. Yes, it is possible. If the aryl group has substituents, the substituents may be those having 1 to 6 carbon atoms. Alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or substitutions of 6 to 13 carbon atoms Unsubstituted aryl groups can also be selected as substituents. C1 to C6 alkyl groups Specifically, the groups include methyl group, ethyl group, propyl group, isopropyl group, and butyl group. Examples include isobutyl groups, tert-butyl groups, and n-hexyl groups. Specifically, examples of cycloalkyl groups having 3 to 6 carbon atoms include cyclopropyl groups and cyclopropyl groups. Examples include cyclopentyl groups, cyclopentyl groups, and cyclohexyl groups. Also, the number of carbon atoms The aryl groups 6 to 13 include phenyl, naphthyl, biphenyl, and fluorenyl groups. The 'L' group can be given as a specific example.

[0207] Also, Q 1 and Q 2 Each of these independently represents N or CR, where R is hydrogen and the number of carbon atoms. A C1 to C6 alkyl group, a C1 to C6 haloalkyl group, or a C6 to C13 alkyl group This represents a substituted or unsubstituted aryl group. Note that Q 1 and Q 2 At least one of them is CR It has. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, and pro groups. Pyr group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hexyl Examples include groups. Furthermore, as for haloalkyl groups having 1 to 6 carbon atoms, there are few. At least one hydrogen atom is combined with a Group 17 element (fluorine, chlorine, bromine, iodine, astatine) Substituted alkyl groups, including alkyl fluorides, alkyl chlorides, alkyl bromides, Examples include alkyl iodides, specifically methyl fluoride groups, methyl chloride groups, and fluoride Examples include ethyl groups and ethyl chloride groups, but the number of halogen elements contained or There may be one or more types. Also, aryl compounds with 6 to 13 carbon atoms. Examples of these groups include phenyl, naphthyl, biphenyl, and fluorenyl groups. Furthermore, the aryl group may have substituents, and the substitution The groups may be bonded to each other to form a ring. The substituent may be an alkyl group having 1 to 6 carbon atoms. The group may also be substituted with an aryl group, a cycloalkyl group having 3 to 6 carbon atoms, or an aryl group having 6 to 13 carbon atoms. It can be selected as a base. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, the kill group includes cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclopropyl group. Examples include chlorohexyl groups. Also, as aryl groups having 6 to 13 carbon atoms... Examples include phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups. It is possible.

[0208] Also, Ar 1 and Ar 2 At least one of the aryl groups represented by and R It has a cyano group.

[0209] <Example 2 of iridium complexes> Furthermore, the iridium complex in one aspect of the present invention is preferably an orthometallic complex. The iridium complex described above is an iridium complex represented by the following general formula (G2).

[0210] [ka]

[0211] In the above general formula (G2), Ar 1 This refers to substituted or unsubstituted ali with 6 to 13 carbon atoms. This represents an aryl group. Examples of aryl groups with 6 to 13 carbon atoms include the phenyl group, naphthyl group, and bifurcation group. Specific examples include phenyl groups and fluorenyl groups. If a substitution group is present, the substituent may be an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 3 to 6 carbon atoms. The cycloalkyl group, or the substituted or unsubstituted aryl group having 6 to 13 carbon atoms, may also be substituted. It can be selected as a base. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, kill groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. For example, phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups can be cited. It is possible.

[0212] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, substituted or unsubstituted aryl groups having 6 to 13 carbon atoms, "Ya" represents either a cyano group. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, kill groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. For example, phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups can be cited. It is possible. 1 ~R 4 The fact that they are all hydrogen makes them easy to synthesize and the raw materials It is advantageous in terms of price.

[0213] Also, Q 1 and Q 2 Each of these independently represents N or CR, where R is hydrogen and the number of carbon atoms. A C1 to C6 alkyl group, a C1 to C6 haloalkyl group, or a C6 to C13 alkyl group This represents a substituted or unsubstituted aryl group. Note that Q 1 and Q 2 At least one of them is CR It has. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, and pro groups. Pyr group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hexyl Examples include groups. Furthermore, as for haloalkyl groups having 1 to 6 carbon atoms, there are few. At least one hydrogen atom is combined with a Group 17 element (fluorine, chlorine, bromine, iodine, astatine) Substituted alkyl groups, including alkyl fluorides, alkyl chlorides, alkyl bromides, Examples include alkyl iodides, specifically methyl fluoride groups, methyl chloride groups, and fluoride Examples include ethyl groups and ethyl chloride groups, but the number of halogen elements contained or There may be one or more types. Also, aryl compounds with 6 to 13 carbon atoms. Examples of these groups include phenyl, naphthyl, biphenyl, and fluorenyl groups. Furthermore, the aryl group may have substituents, and the substitution The groups may be bonded to each other to form a ring. The substituent may be an alkyl group having 1 to 6 carbon atoms. The group may also be substituted with an aryl group, a cycloalkyl group having 3 to 6 carbon atoms, or an aryl group having 6 to 13 carbon atoms. It can be selected as a base. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, the kill group includes cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclopropyl group. Examples include chlorohexyl groups. Also, as aryl groups having 6 to 13 carbon atoms... Examples include phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups. It is possible.

[0214] Also, Ar 1 and R 1 ~R 4 The aryl group represented by , the aryl group represented by R, and R 1 ~ R 4 At least one of them has a cyano group.

[0215] <Example 3 of iridium complexes> Furthermore, in an iridium complex according to one aspect of the present invention, a 4H-triazole skeleton is used as a ligand. Having this allows for high triplet excitation energy levels, especially for blue light. It is preferable because it can be suitably used in light-emitting elements that exhibit high-energy light emission. The iridium complex described above is an iridium complex represented by the following general formula (G3).

[0216] [ka]

[0217] In the above general formula (G3), Ar 1 This refers to substituted or unsubstituted ali with 6 to 13 carbon atoms. This represents an aryl group. Examples of aryl groups with 6 to 13 carbon atoms include the phenyl group, naphthyl group, and bifurcation group. Specific examples include phenyl groups and fluorenyl groups. If a substitution group is present, the substituent may be an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 3 to 6 carbon atoms. The cycloalkyl group, or the substituted or unsubstituted aryl group having 6 to 13 carbon atoms, may also be substituted. It can be selected as a base. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, kill groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. For example, phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups can be cited. It is possible.

[0218] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, substituted or unsubstituted aryl groups having 6 to 13 carbon atoms, "Ya" represents either a cyano group. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, kill groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. For example, phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups can be cited. It is possible. 1 ~R 4 The fact that they are all hydrogen makes them easy to synthesize and the raw materials It is advantageous in terms of price.

[0219] Also, R 5 These are hydrogen, C1-C6 alkyl groups, and C1-C6 haloalkyl groups. , or represents either a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Specifically, alkyl groups 1 to 6 include methyl, ethyl, propyl, and isopropyl groups. Examples include pyr group, butyl group, isobutyl group, tert-butyl group, n-hexyl group, etc. This is possible. Also, as a haloalkyl group having 1 to 6 carbon atoms, at least one hydrogen atom is used. Alkytyl substituted with Group 17 elements (fluorine, chlorine, bromine, iodine, astatine) A group that is an alkyl fluoride group, alkyl chloride group, alkyl bromide group, alkyl iodide group These include, specifically, methyl fluoride group, methyl chloride group, ethyl fluoride group, and ethyl chloride group. Examples include tyl groups, but the number or types of halogen elements included are as follows: It may be one or more. Also, as an aryl group having 6 to 13 carbon atoms, Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. Furthermore, the aryl group may have substituents, and these substituents may be bonded to each other. A ring may be formed. The substituent may be an alkyl group having 1 to 6 carbon atoms, or a ring having 3 carbon atoms. A cycloalkyl group with up to 6 carbon atoms, or an aryl group with 6 to 13 carbon atoms, can also be selected as a substituent. This is possible. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups, ethyl groups, Propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hex Examples include syl groups. Also, examples of cycloalkyl groups having 3 to 6 carbon atoms include... In terms of composition, it consists of cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups. Examples include the phenyl group. Naphthyl groups, biphenyl groups, and fluorenyl groups are some specific examples.

[0220] Also, Ar1 and R 1 ~R 5 The aryl group represented by, and R 1 ~R 4 At least one of them It has a cyano group.

[0221] <Example 4 of iridium complexes> Furthermore, in an iridium complex according to one aspect of the present invention, the imidazole skeleton is used as a ligand. By possessing this, it is possible to have high triplet excitation energy levels, especially for blue light and other energies. It is preferable because it can be suitably used in light-emitting elements that exhibit high energy emission. The rhidium complex is an iridium complex represented by the following general formula (G4).

[0222] [ka]

[0223] In the above general formula (G4), Ar 1 This refers to substituted or unsubstituted ali with 6 to 13 carbon atoms. This represents an aryl group. Examples of aryl groups with 6 to 13 carbon atoms include the phenyl group, naphthyl group, and bifurcation group. Specific examples include phenyl groups and fluorenyl groups. If a substitution group is present, the substituent may be an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 3 to 6 carbon atoms. The cycloalkyl group, or the substituted or unsubstituted aryl group having 6 to 13 carbon atoms, may also be substituted. It can be selected as a base. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, kill groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. For example, phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups can be cited. It is possible.

[0224] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, or substituted or unsubstituted aryl groups with 6 to 13 carbon atoms. It represents one of the groups. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups and ethyl groups. propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n -Examples include hexyl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms, Specifically, this refers to cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohex Examples include syl groups. Also, as aryl groups having 6 to 13 carbon atoms, fer Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. To cut. Also, R 1 ~R 4 The fact that it is all hydrogen is advantageous in terms of ease of synthesis and the cost of raw materials. It is advantageous.

[0225] Also, R 5 and R 6 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 1 to 6 haloalkyl groups, or substituted or unsubstituted aryl groups having 6 to 13 carbon atoms. It represents one of the following. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl group and ethyl group. group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n- Examples include hexyl groups. Also, as haloalkyl groups having 1 to 6 carbon atoms, This is because at least one hydrogen atom is a Group 17 element (fluorine, chlorine, bromine, iodine, astatine). Alkyl alkyl groups substituted by fluoride alkyl groups, chloride alkyl groups, bromide alkyl groups Examples include methyl groups and alkyl iodides, specifically methyl fluoride groups and methyl chloride groups. Examples include ethyl fluoride groups and ethyl chloride groups, but the halogen elements contained are The number or type may be one or multiple. Also, the carbon number may be 6 to 13. Examples of aryl groups include phenyl, naphthyl, biphenyl, and fluorenyl groups. This can be given as an example. Furthermore, the aryl group may have substituents. The substituents may be bonded to each other to form a ring. The substituents may have 1 to 6 carbon atoms. alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or aryl groups having 6 to 13 carbon atoms. The group can also be selected as a substituent. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, te Examples include rt-butyl groups and n-hexyl groups. Also, groups with 3 to 6 carbon atoms. Examples of cloalkyl groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include aryl groups and cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. Examples of these groups include phenyl, naphthyl, biphenyl, and fluorenyl groups. I can do it for you.

[0226] Also, Ar 1 , and R 1 ~R 6 The aryl group represented by, and R 1 ~R 4 at least one It has a cyano group.

[0227] <Example 5 of iridium complexes> Furthermore, in an iridium complex according to one embodiment of the present invention, nitrogen in a nitrogen-containing five-membered heterocyclic skeleton is bonded to the nitrogen. The aryl group to be bonded is a substituted or unsubstituted phenyl group, and can be deposited by vacuum deposition at relatively low temperatures. Furthermore, the triplet excitation energy level becomes higher, especially for high-energy emission such as blue light. It can be suitably used in light-emitting devices that emit light, and is therefore preferred. The iridium complex described above is as follows: These are iridium complexes represented by general formulas (G5) and (G6).

[0228] [ka]

[0229] In the above general formula (G5), R 7 and R 11 This represents an alkyl group having 1 to 6 carbon atoms. , R 7 and R 11 They have the same structure as each other. Specifically, alkyl groups having 1 to 6 carbon atoms are In general, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, Examples include tert-butyl groups and n-hexyl groups.

[0230] Also, R 8 ~R 10 Each of these independently consists of hydrogen, an alkyl group having 1 to 6 carbon atoms, and carbon A cycloalkyl group with a number of 3 to 6, a substituted or unsubstituted phenyl group, or a cyano group. It represents either one. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups, ethyl groups, Propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hex Examples include syl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms are also an option. Specifically, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group These are some examples. 8 ~R 10 At least one of them has a cyano group It is preferable.

[0231] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, or substituted or unsubstituted aryl groups with 6 to 13 carbon atoms. It represents one of the groups. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups and ethyl groups. propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n -Examples include hexyl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms, Specifically, this refers to cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohex Examples include syl groups. Also, as aryl groups having 6 to 13 carbon atoms, fer Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. To cut. Also, R 1 ~R 4 The fact that it is all hydrogen is advantageous in terms of ease of synthesis and the cost of raw materials. It is advantageous.

[0232] Also, R 5 These are hydrogen, C1-C6 alkyl groups, and C1-C6 haloalkyl groups. , or represents either a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Specifically, alkyl groups 1 to 6 include methyl, ethyl, propyl, and isopropyl groups. Examples include pyr group, butyl group, isobutyl group, tert-butyl group, n-hexyl group, etc. This is possible. Also, as a haloalkyl group having 1 to 6 carbon atoms, at least one hydrogen atom is used. Alkytyl substituted with Group 17 elements (fluorine, chlorine, bromine, iodine, astatine) A group that is an alkyl fluoride group, alkyl chloride group, alkyl bromide group, alkyl iodide group These include, specifically, methyl fluoride group, methyl chloride group, ethyl fluoride group, and ethyl chloride group. Examples include tyl groups, but the number or types of halogen elements included are as follows: It may be one or more. Also, as an aryl group having 6 to 13 carbon atoms, Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. Furthermore, the aryl group may have substituents, and these substituents may be bonded to each other. A ring may be formed. The substituent may be an alkyl group having 1 to 6 carbon atoms, or a ring having 3 carbon atoms. A cycloalkyl group with up to 6 carbon atoms, or an aryl group with 6 to 13 carbon atoms, can also be selected as a substituent. This is possible. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups, ethyl groups, Propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hex Examples include syl groups. Also, examples of cycloalkyl groups having 3 to 6 carbon atoms include... In terms of composition, it consists of cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups. Examples include the phenyl group. Naphthyl groups, biphenyl groups, and fluorenyl groups are some specific examples.

[0233] [ka]

[0234] In the above general formula (G6), R 7 and R11 This represents an alkyl group having 1 to 6 carbon atoms. , R 7 and R 11 They have the same structure as each other. Specifically, alkyl groups having 1 to 6 carbon atoms are In general, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, Examples include tert-butyl groups and n-hexyl groups.

[0235] R 8 ~R 10 Each of these independently consists of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a C3 alkyl group. Any of the following: a cycloalkyl group (up to 6), a substituted or unsubstituted phenyl group, or a cyano group. This represents... Specifically, alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, and propyl groups. Isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hexyl group These are some examples. Furthermore, specific examples of cycloalkyl groups having 3 to 6 carbon atoms include These include cyclopropyl groups, cyclobutyl groups, cyclopentyl groups, cyclohexyl groups, etc. It can be listed. Furthermore, R 8 ~R 10 At least one of them has a cyano group. preferable.

[0236] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, or substituted or unsubstituted aryl groups with 6 to 13 carbon atoms. It represents one of the groups. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups and ethyl groups. propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n -Examples include hexyl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms, Specifically, this refers to cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohex Examples include syl groups. Also, as aryl groups having 6 to 13 carbon atoms, fer Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. To cut. Also, R 1 ~R 4 The fact that it is all hydrogen is advantageous in terms of ease of synthesis and the cost of raw materials. It is advantageous.

[0237] Also, R 5 and R 6 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 1 to 6 haloalkyl groups, or substituted or unsubstituted aryl groups having 6 to 13 carbon atoms. It represents one of the following. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl group and ethyl group. group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n- Examples include hexyl groups. Also, as haloalkyl groups having 1 to 6 carbon atoms, This is because at least one hydrogen atom is a Group 17 element (fluorine, chlorine, bromine, iodine, astatine). Alkyl alkyl groups substituted by fluoride alkyl groups, chloride alkyl groups, bromide alkyl groups Examples include methyl groups and alkyl iodides, specifically methyl fluoride groups and methyl chloride groups. Examples include ethyl fluoride groups and ethyl chloride groups, but the halogen elements contained are The number or type may be one or multiple. Also, the carbon number may be 6 to 13. Examples of aryl groups include phenyl, naphthyl, biphenyl, and fluorenyl groups. This can be given as an example. Furthermore, the aryl group may have substituents. The substituents may be bonded to each other to form a ring. The substituents may have 1 to 6 carbon atoms. alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or aryl groups having 6 to 13 carbon atoms. The group can also be selected as a substituent. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, te Examples include rt-butyl groups and n-hexyl groups. Also, groups with 3 to 6 carbon atoms. Examples of cloalkyl groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include aryl groups and cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. Examples of these groups include phenyl, naphthyl, biphenyl, and fluorenyl groups. I can do it for you.

[0238] <Example 6 of iridium complexes> Furthermore, in an iridium complex according to one aspect of the present invention, the 1H-triazole skeleton is used as a ligand. By having this, it is possible to have a high triplet excitation energy level, especially blue Because it can be suitably used in light-emitting elements that exhibit high-energy light such as color, The iridium complex described above is an iridium complex represented by the following general formulas (G7) and (G8). It is the body.

[0239] [ka]

[0240] In the above general formula (G7), Ar 1 This refers to substituted or unsubstituted ali with 6 to 13 carbon atoms. This represents an aryl group. Examples of aryl groups with 6 to 13 carbon atoms include the phenyl group, naphthyl group, and bifurcation group. Specific examples include phenyl groups and fluorenyl groups. If a substitution group is present, the substituent may be an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 3 to 6 carbon atoms. The cycloalkyl group, or the substituted or unsubstituted aryl group having 6 to 13 carbon atoms, may also be substituted. It can be selected as a base. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl propyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-propyl group Examples include cycloaldehyde groups with 3 to 6 carbon atoms. Specifically, kill groups include cyclopropyl group, cyclobutyl group, and cyclopentyl group. Examples include cyclohexyl groups. Also, aryl groups having 6 to 13 carbon atoms. For example, phenyl groups, naphthyl groups, biphenyl groups, and fluorenyl groups can be cited. It is possible.

[0241] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, or substituted or unsubstituted aryl groups with 6 to 13 carbon atoms. It represents one of the groups. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups and ethyl groups. propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n -Examples include hexyl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms, Specifically, this refers to cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohex Examples include syl groups. Also, as aryl groups having 6 to 13 carbon atoms, fer Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. To cut. Also, R 1 ~R 4 The fact that it is all hydrogen is advantageous in terms of ease of synthesis and the cost of raw materials. It is advantageous.

[0242] Also, R 6 These are hydrogen, C1-C6 alkyl groups, and C1-C6 haloalkyl groups. , or represents either a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Specifically, alkyl groups 1 to 6 include methyl, ethyl, propyl, and isopropyl groups. Examples include pyr group, butyl group, isobutyl group, tert-butyl group, n-hexyl group, etc. This is possible. Also, as a haloalkyl group having 1 to 6 carbon atoms, at least one hydrogen atom is used. Alkytyl substituted with Group 17 elements (fluorine, chlorine, bromine, iodine, astatine) A group that is an alkyl fluoride group, alkyl chloride group, alkyl bromide group, alkyl iodide group These include, specifically, methyl fluoride group, methyl chloride group, ethyl fluoride group, and ethyl chloride group. Examples include tyl groups, but the number or types of halogen elements included are as follows: It may be one or more. Also, as an aryl group having 6 to 13 carbon atoms, Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. Furthermore, the aryl group may have substituents, and these substituents may be bonded to each other. A ring may be formed. The substituent may be an alkyl group having 1 to 6 carbon atoms, or a ring having 3 carbon atoms. A cycloalkyl group with up to 6 carbon atoms, or an aryl group with 6 to 13 carbon atoms, can also be selected as a substituent. This is possible. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups, ethyl groups, Propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hex Examples include syl groups. Also, examples of cycloalkyl groups having 3 to 6 carbon atoms include... In terms of composition, it consists of cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups. Examples include the phenyl group. Naphthyl groups, biphenyl groups, and fluorenyl groups are some specific examples.

[0243] Also, Ar 1 , R 1 ~R 4 , and R 6 The aryl group represented by, and R 1 ~R 4 fewer Tomoichi has a cyano group.

[0244] [ka]

[0245] In the above general formula (G8), R 7 and R 11 This represents an alkyl group having 1 to 6 carbon atoms. , R 7 and R 11 They have the same structure as each other. Specifically, alkyl groups having 1 to 6 carbon atoms are In general, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, Examples include tert-butyl groups and n-hexyl groups.

[0246] Also, R 8 ~R 10 Each of these independently consists of hydrogen, an alkyl group having 1 to 6 carbon atoms, and carbon A cycloalkyl group with a number of 3 to 6, a substituted or unsubstituted phenyl group, or a cyano group. It represents either one. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups, ethyl groups, Propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hex Examples include syl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms are also an option. Specifically, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group These are some examples. 8 ~R 10 At least one of them has a cyano group It is preferable.

[0247] Also, R 1 ~R 4 Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a carbon atom. 3 to 6 cycloalkyl groups, or substituted or unsubstituted aryl groups with 6 to 13 carbon atoms. It represents one of the groups. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups and ethyl groups. propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n -Examples include hexyl groups. Also, cycloalkyl groups having 3 to 6 carbon atoms, Specifically, this refers to cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohex Examples include syl groups. Also, as aryl groups having 6 to 13 carbon atoms, fer Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. To cut. Also, R 1 ~R 4 The fact that it is all hydrogen is advantageous in terms of ease of synthesis and the cost of raw materials. It is advantageous.

[0248] Also, R 6 These are hydrogen, C1-C6 alkyl groups, and C1-C6 haloalkyl groups. , or represents either a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Specifically, alkyl groups 1 to 6 include methyl, ethyl, propyl, and isopropyl groups. Examples include pyr group, butyl group, isobutyl group, tert-butyl group, n-hexyl group, etc. This is possible. Also, as a haloalkyl group having 1 to 6 carbon atoms, at least one hydrogen atom is used. Alkytyl substituted with Group 17 elements (fluorine, chlorine, bromine, iodine, astatine) A group that is an alkyl fluoride group, alkyl chloride group, alkyl bromide group, alkyl iodide group These include, specifically, methyl fluoride group, methyl chloride group, ethyl fluoride group, and ethyl chloride group. Examples include tyl groups, but the number or types of halogen elements included are as follows: It may be one or more. Also, as an aryl group having 6 to 13 carbon atoms, Examples include the nyl group, naphthyl group, biphenyl group, and fluorenyl group. Furthermore, the aryl group may have substituents, and these substituents may be bonded to each other. A ring may be formed. The substituent may be an alkyl group having 1 to 6 carbon atoms, or a ring having 3 carbon atoms. A cycloalkyl group with up to 6 carbon atoms, or an aryl group with 6 to 13 carbon atoms, can also be selected as a substituent. This is possible. Specifically, alkyl groups having 1 to 6 carbon atoms include methyl groups, ethyl groups, Propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, n-hex Examples include syl groups. Also, examples of cycloalkyl groups having 3 to 6 carbon atoms include... In terms of composition, it consists of cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups. Examples include the phenyl group. Naphthyl groups, biphenyl groups, and fluorenyl groups are some specific examples.

[0249] <Examples of substituents> R in the above general formulas (G2) to (G8) 1 ~R 4 Alkyl and aryl groups represented by As a base, for example, apply a group represented by the following structural formulas (R-1) to (R-29). This is possible. However, the groups that can be used as alkyl and aryl groups are not limited to these. I can't.

[0250] [ka]

[0251] Furthermore, in general formulas (G1) to (G4) and (G7), Ar 1 A is represented as In the reel base and general formula (G1), Ar 2 Examples of aryl groups represented by this symbol include, for example, The groups represented by the above structural formulas (R-12) to (R-29) can be applied. Ar 1 and Ar 2 These are not the only groups that can be used as such.

[0252] Furthermore, the R in general formulas (G5), (G6), and (G8) 7 and R 11 Alkyl represented by For example, the groups represented by the above structural formulas (R-1) to (R-10) can be applied. It is possible. Furthermore, the groups that can be used as alkyl groups are not limited to these.

[0253] Furthermore, the R in general formulas (G5), (G6), and (G8) 8 ~R 10 Alkyl represented by The phenyl group, whether substituted or unsubstituted, is, for example, the above structural formulas (R-1) to (R-2) The group represented in 2) can be applied. Note that it can be used as an alkyl group or a phenyl group. These are not the only possible bases.

[0254] Furthermore, R in the above general formulas (G3) to (G6) 5, and general formulas (G4), (G6) to ( G8) R 6 The alkyl group, aryl group, or haloalkyl group represented by the above is, for example, The following structural formulas (R-1) to (R-29), and the following structural formulas (R-30) to (R-37) The groups shown can be applied. Note that alkyl groups, aryl groups, or haloalkyl groups can be applied. These are not the only groups that can be used as a lu group.

[0255] [ka]

[0256] <Specific examples of iridium complexes> The specific structures of the iridium complex represented by the above general formulas (G1) to (G8) are as follows: Examples include compounds represented by the following structural formulas (100) to (134). Iridium complexes represented by general formulas (G1) through (G8) are not limited to the examples shown below.

[0257] [ka]

[0258] [ka]

[0259] [ka]

[0260] [ka]

[0261] [ka]

[0262] [ka]

[0263] As described above, the iridium complex according to one aspect of the present invention has a relatively low HOMO level and L Because it has a UMO level, it is suitable as a guest material for light-emitting devices. It is possible to fabricate light-emitting elements with good optical efficiency. Furthermore, iridium complex according to one embodiment of the present invention Because the body has high triplet excitation energy levels, it is particularly suitable as a guest material for blue light-emitting elements. It is suitable as a material. This makes it possible to create a blue light-emitting element with good luminescence efficiency. Furthermore, the iridium complex according to one embodiment of the present invention exhibits good resistance to repeated oxidation and reduction. Because of this property, using the iridium complex in a light-emitting element results in a light-emitting element with a good operating life. It is possible to produce offspring. As described above, the iridium complex according to one aspect of the present invention is a luminescent element It is a suitable material for use in children.

[0264] Furthermore, the iridium complex according to one aspect of the present invention may be produced by vapor deposition (including vacuum deposition) and inkjet deposition. The film can be formed using methods such as the stencil method, coating method, and gravure printing.

[0265] The compounds shown in this embodiment can be appropriately combined with the configurations shown in other embodiments. It can be used.

[0266] (Embodiment 3) In this embodiment, the structure represented by general formulas (G1), (G3), (G4), and (G7) This section describes an example of a method for synthesizing iridium complexes, including the compound. Various reactions can be applied as such. For example, the following synthesis reactions can be carried out. Therefore, iridium complexes represented by general formulas (G1), (G3), (G4), and (G7) It is possible to synthesize iridium complexes. Furthermore, one embodiment of the present invention is a method for synthesizing iridium complexes, The synthesis method is not limited to the one shown below.

[0267] <Method for synthesizing iridium complexes represented by general formula (G1)> This section describes an example of a synthesis method for iridium complexes having the structure represented by general formula (G1). ru.

[0268] As shown in the synthesis scheme (a) below, a nitrogen-containing five-membered ring derivative represented by general formula (G0) And, iridium metal compounds containing halogens (iridium chloride hydrate, hexachloroiridium (e.g., ammonium ammonium phosphate), or iridium organometallic complex compounds (acetylacetonate complex) After mixing with a compound (such as a diethyl sulfide complex), heating produces the compound of general formula (G1). An iridium complex having the structure represented by can be obtained. Furthermore, this heating process can be used to obtain an iridium complex. , a nitrogen-containing five-membered ring derivative represented by general formula (G0), and an iridium metal compound containing a halogen A substance, or an iridium organometallic complex compound, in an alcohol-based solvent (glycerol, ethylene After dissolving in (such as glycol, 2-methoxyethanol, 2-ethoxyethanol, etc.), proceed. That's fine.

[0269] [ka]

[0270] In synthesis scheme (a), Ar 1 and Ar 2 Each of these independently has 6 to 1 carbon atoms. 3 represents a substituted or unsubstituted aryl group. Also, Q 1 and Q 2Each of them is independent of N Alternatively, it represents CR, where R is hydrogen, an alkyl group having 1 to 6 carbon atoms, or a halo having 1 to 6 carbon atoms. This represents an alkyl group, or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Q 1 and Q 2 At least one of them has CR. Also, Ar 1 and Ar 2 Ants The aryl group and at least one of the aryl groups represented by R have a cyano group.

[0271] Furthermore, as a method for synthesizing iridium complexes having the structure represented by general formula (G1), The synthesis scheme is not limited to (a). For example, as an example of another synthesis method, the following synthesis scheme is used. As shown in (a'), Ar 3 and Ar 4 At least one of the aryl groups represented is iridium complex having ligands substituted with rogenic groups and aryl groups substituted with cyano groups By reacting a boronic acid compound or copper cyanide with the compound, the compound represented by the general formula (G1) is obtained. An iridium complex having a structure can be obtained. 3 and Ar 4 Represented by At least one of the aryl groups is a boronic acid, a boronic acid ester, or a cyclic triol boronic acid. iridium complex with a compound that is a rate salt as a ligand, and halogen substituted with a cyano group You can also react the aryl compound with the other compound.

[0272] [ka]

[0273] In the above synthesis scheme (a'), Ar 1 and Ar 2 Each of them independently has 6 carbon atoms. It represents 13 substituted or unsubstituted aryl groups. Also, Q 1 and Q 2 Each is independent Here, N or CR represents hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. This represents a haloalkyl group or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Q 1 and Q 2 At least one of them has CR. Also, Ar 1 and Ar 2 The table The aryl group and at least one of the aryl groups represented by R have a cyano group.

[0274] As described above, iridium complexes of general formula (G1) can be synthesized.

[0275] <Method for synthesizing iridium complexes represented by general formula (G3)> Next, we will describe an example of a method for synthesizing iridium complexes having a structure represented by general formula (G3). I will explain.

[0276] <<Synthesis method for 1,2,4-triazole derivatives>> First, a method for synthesizing 1,2,4-triazole derivatives represented by the following general formula (G0-X1). Let me explain an example.

[0277] [ka]

[0278] Note that in the general formula (G0-X1), Ar 1 This is a substituted or unsubstituted a carbon atom with 6 to 13 carbon atoms. It represents a reel group. Also, R 1 ~R 4 These are, independently, hydrogen and an alkyl group having 1 to 6 carbon atoms. C13 group, C3 to C6 cycloalkyl group, C6 to C13 substituted or unsubstituted group It represents either a reel group or a cyano group. Also, R 5 This is hydrogen, and carbon atoms with 1 to 6 carbon atoms. Lukyl group, C1 to C6 haloalkyl group, or C6 to C13 substituted or unsubstituted group. It represents one of the substituted aryl groups. Also, Ar 1 and R 1 ~R 5 The aryl group represented by and R 1 ~R 4 At least one of them has a cyano group.

[0279] As shown in the synthesis scheme (b) below, the hydrazide compound (A1) and the thioetherification By reacting with a compound or an N-substituted thioamide compound (A2), the general formula (G A 1,2,4-triazole derivative represented by (0-X1) can be obtained. In scheme (b), Ar 1 This is a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. It represents R. 1 ~R 4 Each of these independently consists of hydrogen, an alkyl group having 1 to 6 carbon atoms, and carbon Cycloalkyl groups with 3 to 6 prime atoms, or substituted or unsubstituted ali groups with 6 to 13 carbon atoms. It represents one of the R groups. 5 This includes hydrogen, an alkyl group having 1 to 6 carbon atoms, and a C1 A haloalkyl group having 6 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. It represents either one. Also, Ar 1 and R 1 ~R 5 The aryl group represented by, and R 1 ~R 4 of At least one of them has a cyano group.

[0280] [ka]

[0281] However, the synthesis method for 1,2,4-triazole derivatives represented by the general formula (G0-X1) is The synthesis scheme is not limited to (b). For example, as an example of another synthesis method, the following synthesis As shown in scheme (b'), a dihydrazide compound (A1') and a primary amine compound ( Another method involves reacting with A2'). Note that in synthesis scheme (b'), Ar 1 teeth, It represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Also, R 1 ~R 4 That Each independently includes hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and carbon This represents either a substituted or unsubstituted aryl group or a cyano group, with prime numbers between 6 and 13. Also, R 5 hydrogen, alkyl groups having 1 to 6 carbon atoms, haloalkyl groups having 1 to 6 carbon atoms, Alternatively, it represents either a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Also, A r 1 and R 1 ~R 5 The aryl group represented by, and R 1 ~R 4 At least one of them is a cyano group It has.

[0282] [ka]

[0283] As described above, the 1,2,4-triazole derivative represented by the general formula (G0-X1) is It can be synthesized using a very simple synthesis scheme.

[0284] Subsequently, using the same synthesis method as the above synthesis scheme (a), the general formula (G0-X1) The 1,2,4-triazole derivatives shown and the halogen-containing iridium metal compounds (salts) Iridium hydrate, ammonium hexachloroiridiate, etc., or iridium-containing Mixed with metallometallic complex compounds (acetylacetonate complex, diethyl sulfide complex, etc.) Subsequently, heating is performed to obtain an iridium complex having the structure represented by general formula (G3). It is possible.

[0285] As described above, iridium complexes of general formula (G3) can be synthesized.

[0286] In one embodiment of the present invention, 1,2,4-triazole represented by general formula (G3) is used. To obtain an iridium complex, which is an orthometallic complex with an iridium derivative as a ligand, the general formula ( The 5-position (i.e., R) of the 1,2,4-triazole derivative represented by G0-X1) 5 Replace with ) You may introduce a base, especially R. 5 For example, alkyl groups having 1 to 6 carbon atoms, C1 to 6 Either a haloalkyl group or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. When using R 5 Compared to the case where hydrogen is used, the yield in synthesis scheme (a) This is preferable because it can increase the rate.

[0287] <Method for synthesizing iridium complexes represented by general formula (G4)> Next, we will describe an example of a method for synthesizing iridium complexes having a structure represented by general formula (G4). I will explain.

[0288] <<Synthesis Method for Imidazole Derivatives>> First, let's look at an example of a synthesis method for imidazole derivatives represented by the following general formula (G0-X2). I will explain.

[0289] [ka]

[0290] Note that in the general formula (G0-X2), Ar 1 This is a substituted or unsubstituted a carbon atom with 6 to 13 carbon atoms. It represents a reel group. Also, R 1 ~R 4 These are, independently, hydrogen and an alkyl group having 1 to 6 carbon atoms. A C3-C6 cycloalkyl group, or a substituted or unsubstituted C6-C13 group. It represents one of the aryl groups of substitution. Also, Ar 1 and R 1 ~R 4 The aryl group represented by, and biR 1 ~R 4 At least one of them has a cyano group.

[0291] As shown in the synthesis scheme (c) below, first, N-(2-chloroethyl)benzamidate is performed. The compound (B1) is reacted with a chlorinating agent, and then reacted with a primary amine compound (B2). This allows us to obtain the intermediate (B3). Note that phosphorus pentachloride is used as the chloroforming agent. Examples include phosphoryl chloride. Then, the intermediate (B3) is reacted with the dehydrogenating agent. By doing so, an imidazole derivative represented by the general formula (G0-X2) can be obtained. Examples of dehydrogenating agents include potassium permanganate and benzoquinone derivatives. In addition, in synthesis scheme (c), Ar 1 This refers to substitution or absence of carbon atoms with 6 to 13 carbon atoms. It represents the aryl group of substitution. Also, R 1 ~R 4 These are, independently, hydrogen and carbon atoms with 1 to 6 carbon atoms. Alkyl groups, cycloalkyl groups having 3 to 6 carbon atoms, or substitutions of 6 to 13 carbon atoms represents any of the unsubstituted aryl groups. Also, Ar1 and R 1 ~R 4 The arrow that represents Base, and R 1 ~R 4 At least one of them has a cyano group.

[0292] [ka]

[0293] However, the synthesis method for imidazole derivatives represented by the general formula (G0-X2) is synthetic ski It is not limited to (c). For example, as an example of another synthesis method, the following synthesis scheme (c As shown in '), a thioether compound or an iminochloride compound (B1') and First, react with minoacetaldehyde dimethyl acetal, then add an inorganic acid and react again. There is also this method. Examples of inorganic acids include phosphoric acid and hydrochloric acid. Furthermore, synthetic skis... In Mu (c'), Ar 1 This represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Yes. Also, R 1 ~R 4 Each of these independently consists of hydrogen, an alkyl group having 1 to 6 carbon atoms, and carbon Cycloalkyl groups with 3 to 6 carbon atoms, or substituted or unsubstituted alkyl groups with 6 to 13 carbon atoms. It represents one of the Ar groups. 1 and R 1 ~R 4 The aryl group represented by, and R 1 ~ R 4 At least one of them has a cyano group.

[0294] [ka]

[0295] Next, we will describe an example of a synthesis method for imidazole derivatives represented by the following general formula (G0-X3). I will explain.

[0296] [ka]

[0297] Note that in the general formula (G0-X3), Ar 1 This is a substituted or unsubstituted a carbon atom with 6 to 13 carbon atoms. It represents a reel group. Also, R 1 ~R 4 These are, independently, hydrogen and aluminum atoms having 1 to 6 carbon atoms. Kill group, cycloalkyl group having 3 to 6 carbon atoms, or substituted or unsubstituted group having 6 to 13 carbon atoms. It represents one of the substituted aryl groups. Also, R 5 and R 6 These are, independently, hydrogen and carbon Alkyl alkyl groups with 1 to 6 prime numbers, haloalkyl groups with 1 to 6 carbon atoms, or groups with 6 to 13 carbon atoms It represents either a substituted or unsubstituted aryl group. Also, Ar 1 and R 1 ~R 6 but The aryl group represented, and R 1 ~R 6 At least one of them has a cyano group.

[0298] As shown in the synthesis scheme (c'') below, a β-diketone compound (B1'') and a primary a Mix the mine compound (B2), the benzaldehyde compound (B3''), and ammonium acetate. There is also a method to induce the reaction. Note that in the synthesis scheme (c''), Ar 1 is a carbon-6 Represents substituted or unsubstituted aryl groups up to 13. Also, R 1 ~R 4 Each is independent , hydrogen, C1 to C6 alkyl groups, C3 to C6 cycloalkyl groups, or carbon It represents one of substituted or unsubstituted aryl groups, numbered 6 to 13. Also, R 5 and R 6 These are, independently, hydrogen, an alkyl group having 1 to 6 carbon atoms, and a haloalkyl group having 1 to 6 carbon atoms. It represents either an aryl group or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Ta, Ar 1 and R 1 ~R 4 The aryl group represented by, and R 1 ~R 4 At least one of them is It has that group.

[0299] [ka]

[0300] As described above, imidazole derivatives represented by the general formula (G0-X3) are very simple compounds. It can be synthesized using the synthesis scheme.

[0301] Subsequently, using the same synthesis method as the above synthesis scheme (a), the general formula (G0-X3) The imidazole derivatives shown and the halogen-containing iridium metal compounds (iridium chloride) Hydrate (e.g., ammonium hexachloroiridiate), or iridium organometallic complex After mixing with a compound (acetylacetonate complex, diethyl sulfide complex, etc.), heat the mixture. This allows us to obtain iridium complexes having a structure represented by the general formula (G4). .

[0302] As described above, iridium complexes of general formula (G4) can be synthesized.

[0303] <Method for synthesizing iridium complexes represented by general formula (G7)> Next, we will describe an example of a method for synthesizing iridium complexes having a structure represented by general formula (G7). I will explain.

[0304] ≪Synthesis Method for 1H-1,2,4-Triazole Derivatives≫ First, the 1H-1,2,4-triazole derivative represented by the following general formula (G0-X4) An example of a synthesis method will be described.

[0305] [ka]

[0306] Note that in the general formula (G0-X4), Ar 1 This is a substituted or unsubstituted a carbon atom with 6 to 13 carbon atoms. It represents a reel group. Also, R 1 ~R 4 These are, independently, hydrogen and aluminum atoms having 1 to 6 carbon atoms. Kill group, cycloalkyl group having 3 to 6 carbon atoms, or substituted or unsubstituted group having 6 to 13 carbon atoms. It represents one of the substituted aryl groups. Also, R 6 These are hydrogen and alkyl groups having 1 to 6 carbon atoms. , a haloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aloalkyl group having 6 to 13 carbon atoms It represents one of the reel groups. Also, Ar 1 , R 1 ~R 4 , and R 6 The aryl group represented by and R 1 ~R 4 At least one of them has a cyano group.

[0307] As shown in the synthesis scheme (d) below, an acylamidine compound (C1) and hydrazine By reacting it with compound (C2), a 1H-1,2,4-triazole derivative is obtained. In the formula, Z represents the group that is eliminated by the ring-closing reaction (leaving group), and is an alkoxy group, A Examples include lucirthio groups, amino groups, and cyano groups. Note that in the above synthesis scheme (d) And, Ar 1 R represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. 1 ~R 4 These are, independently, hydrogen, an alkyl group having 1 to 6 carbon atoms, and a syl group having 3 to 6 carbon atoms. Either a chloroalkyl group or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. It represents R. 6 This includes hydrogen, alkyl groups having 1 to 6 carbon atoms, and haloal groups having 1 to 6 carbon atoms. This represents either a kill group or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. Also, Ar 1 , R 1 ~R 4 , and R 6 The aryl group represented by, and R 1 ~R 4 at least Another has a cyano group.

[0308] [ka]

[0309] However, the synthesis method for 1H-1,2,4-triazole derivatives is limited to synthesis scheme (d) only. It is not limited to the above. Reazole derivatives can be synthesized using a very simple synthesis scheme.

[0310] Subsequently, using the same synthesis method as the above synthesis scheme (a), the general formula (G0-X4) The 1H-1,2,4-triazole derivatives and the halogen-containing iridium metal compounds substances (such as iridium chloride hydrate, ammonium hexachloroiridiate, etc.), or iridium Mix with um organometallic complex compounds (acetylacetonate complex, diethyl sulfide complex, etc.) After bonding, heating is performed to obtain an iridium complex having a structure represented by general formula (G7). You can obtain this.

[0311] The compounds shown in this embodiment can be appropriately combined with the configurations shown in other embodiments. It can be used.

[0312] (Embodiment 4) In this embodiment, the configuration example of a light-emitting element using an iridium complex described in Embodiment 2 is as follows: This will be explained below using Figures 3(A) and 3(B).

[0313] <Example of light-emitting element configuration> Figure 3(A) is a schematic cross-sectional view of a light-emitting element 152 according to one embodiment of the present invention.

[0314] The light-emitting element 152 has an EL layer 100 between a pair of electrodes, and any of the EL layer 100 This is a light-emitting element having an iridium complex as described in Embodiment 2 in its layer.

[0315] Furthermore, the EL layer 100 has at least an emissive layer 140. In addition to the light-emitting layer 140, there is also the hole injection layer 111 and the hole transport layer 112 shown in Embodiment 1. The configuration may include an electron transport layer 118 and an electron injection layer 119. This is not limited to the layered structure of 00.

[0316] Furthermore, the pair of electrodes (electrode 101 and electrode 102) and hole injection layer 1 in this embodiment 11. As for the hole transport layer 112, electron transport layer 118, and electron injection layer 119, in Embodiment 1 The materials listed can be used.

[0317] Furthermore, Figure 3(B) is a schematic cross-sectional view showing an example of the light-emitting layer 140 of the light-emitting element 152. Yes. The light-emitting layer 140 has a host material 141 and a guest material 142. Host material Material 141 can be the same material described for host material 131 shown in Embodiment 1. That is, the organic compound 141_1 and organic compound 141_ that the host material 141 possesses 2 is the organic compound 131_1 and organic compound 131_2 shown in Embodiment 1, respectively. The materials listed may be used.

[0318] Furthermore, the iridium complex described in Embodiment 2 has a relatively low HOMO level and LU Because it has an MO level, it is suitable as a guest material for a light-emitting element according to one embodiment of the present invention. In other words, the iridium complex described in Embodiment 2 is used as the guest material 142 of the light-emitting element 152. By using it as such, a light-emitting element with good luminescence efficiency can be manufactured. Because the zinc complex has a high triplet excitation energy level, it exhibits a blue light with good luminescence efficiency. Optical elements can be fabricated. Therefore, by using the configuration of this embodiment, It is possible to fabricate light-emitting devices with good luminescence efficiency and a blue emission spectral peak. Furthermore, the iridium complex has good resistance to repeated oxidation and reduction. This makes it possible to create light-emitting elements with a good operating life.

[0319] Furthermore, similar to the light emission mechanism shown in Figures 2(A) and 2(B), the HOMO level of guest material 142 It is lower than the HOMO level of organic compound 141_2, and the LUMO level of guest material 142. The level is preferably higher than the LUMO level of organic compound 141_1. In Embodiment 2 The iridium complex shown has relatively low HOMO and LUMO levels. It can be suitably used as a guest material in the above configuration. That is, guest material 142 The energy difference between the LUMO level and the HOMO level of organic compound 141_1 is the LUMO level The position is made larger than the energy difference between it and the HOMO level of organic compound 141_2, The only thing that needs to be selected is compound 141_1, organic compound 141_2, and guest material 142. The iridium complex shown in Embodiment 2 is preferred as guest material 142. By configuring it, guest material 142 and organic compound 141_1 or organic compound 141 _2 and the formation of excited complexes can be suppressed, thus exhibiting high luminescence efficiency. Optical devices can be fabricated.

[0320] Furthermore, the iridium complex shown in Embodiment 2 converts triplet excitation energy into light emission. It has the function of [doing something]. Therefore, the iridium complex has the energy between the LUMO level and the HOMO level Due to the energy difference, it is possible to emit light with lower energy. Therefore, the iridium The energy difference between the LUMO level and the HOMO level of the LU complex is the LU of organic compound 141_1. When the energy difference between the MO level and the HOMO level of organic compound 141_2 is greater than the energy difference between the MO level and the HOMO level of organic compound 141_2, However, the energy of the luminescence or absorption exhibited by the iridium complex may be organically modified. Energy difference between the LUMO level of compound 141_1 and the HOMO level of organic compound 141_2 In the smaller case, it is formed by organic compound 141_1 and organic compound 141_2. This allows for the transfer of excitation energy from the excited complex to the iridium complex, and the iridium complex It can emit light from its body.

[0321] Furthermore, the oxidation potential of guest material 142 is higher than that of organic compound 141_2, and Furthermore, it is preferable that the reduction potential of guest material 142 is lower than that of organic compound 141_1. The iridium complex shown in Embodiment 2 exhibits relatively high oxidation and reduction potentials. As shown above, it can be suitably used as a guest material in the above configuration. By doing so, guest material 142 and organic compound 141_1 or organic compound 141_2 Therefore, the formation of excited complexes can be suppressed, resulting in a light-emitting element that exhibits high luminescence efficiency. It is possible to produce offspring. Note that oxidation potential and reduction potential are determined by cyclic bonding. It can be measured by the luminometry (CV) method.

[0322] The light-emitting layer 140 can also be composed of two or more layers. For example, the first When the first light-emitting layer and the second light-emitting layer are stacked in order from the hole transport layer side to form the light-emitting layer 140, A material having hole transport properties is used as the host material for the first light-emitting layer, and the host material for the second light-emitting layer This includes configurations that use materials with electron transport properties. Also, the first light-emitting layer and the second light-emitting layer The light-emitting material in the light layer may be the same material or different materials, and the same color light-emitting material may be emitted. Even if a material has the function of emitting light, it is a material that has the function of emitting light of different colors. It is also acceptable to use two light-emitting layers, each containing a light-emitting material that exhibits different colors of light emission. By using each of them, multiple light sources can be obtained simultaneously. In particular, the two light-emitting layers exhibit It is preferable to select the light-emitting material used in each light-emitting layer so that it becomes white due to the light emission.

[0323] Furthermore, in the light-emitting layer 140, materials other than the host material 141 and the guest material 142 are used. It's okay to have it.

[0324] The light-emitting layer 140 is produced by vapor deposition (including vacuum deposition), inkjet, coating, and It can be formed by methods such as labia printing. In addition to the materials mentioned above, quantum dots, etc. Even if it has an inorganic compound or polymer compound (oligomer, dendrimer, polymer, etc.) good.

[0325] Furthermore, other configurations of the light-emitting element 152 shown in this embodiment include the form You can refer to the configuration of the light-emitting element 150 shown in Form 1.

[0326] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0327] (Embodiment 5) In this embodiment, the configuration of the light-emitting element differs from that shown in Embodiments 1 and 4. The following explanation of the light-emitting element with the configuration described above will be given using Figure 4. Note that in Figure 4, Figure 1 Areas with the same function as the symbols shown in (A) should be given the same hatch pattern and the symbols should be omitted. Abbreviations may be used. Also, similar functions are indicated with the same symbols, and their details are not shown. Explanations may be omitted.

[0328] Figure 4 is a schematic cross-sectional view of the light-emitting element 250.

[0329] The light-emitting element 250 shown in Figure 4 has multiple elements between a pair of electrodes (electrode 101 and electrode 102). It has light-emitting units (light-emitting units 106 and 108 in Figure 4). One of the multiple light-emitting units is shown in Figure 1 or Figure 3 as E It is preferable that it has a similar configuration to the L layer 100. That is, the light-emitting element 150 shown in Figure 1 and The light-emitting element 152 shown in Figure 3 has one light-emitting unit, and the light-emitting element 250 has multiple It is preferable to have a light-emitting unit. In the light-emitting element 250, the electrode 101 is the anode and Assuming that it functions as such, and that electrode 102 functions as the cathode, the following will be explained, but the light-emitting element 250 The configuration can also be reversed.

[0330] Furthermore, in the light-emitting element 250 shown in Figure 4, the light-emitting unit 106 and the light-emitting unit 108 The two are stacked, and between the light-emitting unit 106 and the light-emitting unit 108 there is a charge generation layer 1 15 is provided. Note that even though the light-emitting unit 106 and the light-emitting unit 108 have the same configuration, they are different. The following configuration is also acceptable. For example, the light-emitting unit 108 may have an EL layer 100 as shown in Figure 1 or Figure 3. It is preferable to use [this].

[0331] Furthermore, the light-emitting element 250 has a light-emitting layer 170 and a light-emitting layer 180. In addition to the light-emitting layer 170, knit 106 also includes a hole injection layer 111, a hole transport layer 112, and an electron transport layer. It has a layer 113 and an electron injection layer 114. The light-emitting unit 108 also has a light-emitting layer 180 In addition, there is a hole injection layer 116, a hole transport layer 117, an electron transport layer 118, and an electron injection layer 11 It has 9.

[0332] The charge generation layer 115 is a hole transport material to which an acceptor substance, which is an electron acceptor, is added. Even with such a configuration, the electron transport material is combined with a donor substance that acts as an electron donor. This is also acceptable. Furthermore, both of these configurations may be stacked.

[0333] If the charge generation layer 115 contains a composite material of an organic compound and an acceptor substance, The composite material used is a composite material that can be used in the hole injection layer 111 shown in Embodiment 1. That's all. As for organic compounds, aromatic amine compounds, carbazole compounds, aromatic carbon compounds Various compounds are used, such as hydrogen and polymer compounds (oligomers, dendrimers, polymers, etc.). It can exist. Furthermore, as an organic compound, its hole mobility is 1 × 10⁻⁶. -6 cm 2 / Vs It is preferable to use an organic compound that has the above characteristics. However, it is preferable to use one with higher hole transport ability than electron transport ability. Other substances may be used as long as they are suitable. Organic compounds and acceptor substances Composite materials have excellent carrier implantation and carrier transport properties, making them suitable for low-voltage and low-current driving applications. This enables motion. Note that, as in the light-emitting unit 108, the anode side of the light-emitting unit If the surface is in contact with the charge generation layer 115, the charge generation layer 115 will be the hole of the light-emitting unit. Since it can also function as an injection layer or hole transport layer, the light-emitting unit has a hole injection layer. Alternatively, the configuration may not include a hole transport layer.

[0334] Furthermore, the charge generation layer 115 is a layer containing a composite material of an organic compound and an acceptor substance, and other It may be formed as a laminated structure by combining layers made of the following materials. For example, organic A layer containing a composite material of a compound and an acceptor substance, and one selected from among electron-donating substances. A layer containing the compound and a compound with high electron transport properties may be formed by combining them. A layer containing a composite material of an organic compound and an acceptor substance, and a layer containing a transparent conductive material are combined. They may be formed together.

[0335] Furthermore, the charge generation layer 115 sandwiched between the light-emitting unit 106 and the light-emitting unit 108 is electric When a voltage is applied to electrode 101 and electrode 102, electrons are injected into one of the light-emitting units. Any method that injects holes into the other light-emitting unit is acceptable. For example, in Figure 4, electrode 1 When a voltage is applied such that the potential of electrode 01 is higher than the potential of electrode 102, charge generation occurs. Layer 115 injects electrons into light-emitting unit 106 and holes into light-emitting unit 108. .

[0336] Furthermore, the charge generation layer 115 has light transmission to visible light (specifically) from the viewpoint of light extraction efficiency. It is preferable that the charge generation layer 115 has a visible light transmittance of 40% or more. Furthermore, the charge generation layer 115 has lower conductivity than the pair of electrodes (electrode 101 and electrode 102). It still works.

[0337] By forming the charge generation layer 115 using the materials described above, the light-emitting layer is stacked in the field This can suppress the rise in drive voltage during operation.

[0338] Furthermore, Figure 4 describes a light-emitting element having two light-emitting units, but 3 The same method can be applied to light-emitting devices that have multiple light-emitting units stacked on top of each other. As shown in the light-emitting element 250, multiple light-emitting units are separated between a pair of electrodes by a charge generation layer. By arranging them in this way, high-brightness illumination is possible while maintaining a low current density, and furthermore, a long lifespan is achieved. This enables the creation of light-emitting elements with low power consumption.

[0339] Furthermore, of the multiple units, at least one unit is configured according to Embodiment 1 and the implementation. By applying the configuration shown in Embodiment 4, a light-emitting element with high luminescence efficiency can be provided. It is possible.

[0340] In addition, in each of the above configurations, the luminescent unit 106 and the luminescent unit 108 are used The light-emitting material (luminescent material) may be the same or different. Luminescent unit 10 When 6 and the light-emitting unit 108 have a guest material that has the function of emitting light of the same color. Therefore, the light-emitting element 250 is preferable as a light-emitting element that exhibits high luminous brightness with a low current value. The light-emitting unit 106 and the light-emitting unit 108 have the function of emitting light of different colors from each other. When a guest material is present, the light-emitting element 250 preferably becomes a light-emitting element that exhibits multicolor emission. i. In this case, either one or both of the light-emitting layer 170 and the light-emitting layer 180 have different emission wavelengths. By using multiple luminescent materials, the emission spectrum exhibited by the light-emitting element 250 is different. Since the light is a composite of emission with emission peaks, it has at least two peaks. This results in an emission spectrum.

[0341] The above configuration is also suitable for obtaining white light emission. Light from the light-emitting layer 170 and the light-emitting layer 180 By making them complementary colors to each other, white light emission can be obtained. In particular, color rendering Guests should aim for high white light emission, or light emission that includes at least red, green, and blue. It is preferable to select the materials.

[0342] Furthermore, either one or both of the light-emitting layer 170 and the light-emitting layer 180 may be further divided into layers. Each of the divided layers may contain a different light-emitting material. Either or both of layer 170 and the light-emitting layer 180 are composed of two or more layers. It is also possible to stack the first light-emitting layer and the second light-emitting layer in order from the hole transport layer side. When using this as a light-emitting layer, a material having hole transport properties is used as the host material for the first light-emitting layer. One configuration involves using a material with electron transport properties as the host material for the second light-emitting layer. In this case, the light-emitting materials of the first light-emitting layer and the second light-emitting layer may be the same material but different materials. Even if they are materials, even if they have the function of emitting light of the same color, they may emit light of different colors. It may be a material having the function of exhibiting the following: It may have the function of exhibiting light emission of different colors from each other. The configuration, which has multiple light-emitting materials, produces high color rendering consisting of the three primary colors or four or more light-emitting colors. It is also possible to obtain white light emission.

[0343] Materials that can be used for the light-emitting layer 170 and the light-emitting layer 180 include those from the previous embodiment 1. Materials that can be used in the light-emitting layer 130 shown and the light-emitting layer 140 shown in Embodiment 4 are supported. It can be used as is. Also, the iridium complex shown in Embodiment 2 can be used as a guest material. This is preferable. By doing so, a light-emitting element with high luminescence efficiency can be fabricated.

[0344] Furthermore, the light-emitting unit 106, the light-emitting unit 108, and the charge generation layer 115 are produced by a vapor deposition method. Formed by methods such as vacuum deposition, inkjet printing, coating, and gravure printing. It is possible.

[0345] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible to be there.

[0346] (Embodiment 6) In this embodiment, the configuration differs from that shown in Embodiments 1, 4, and 5. An example of a light-emitting element with the above configuration will be described below with reference to Figures 5 to 8.

[0347] <Example of light-emitting element configuration 1> Figures 5(A) and 5(B) are cross-sectional views showing a light-emitting element according to one embodiment of the present invention. In (B), the same hatching is used in areas that have the same function as the symbols shown in Figure 1(A). In some cases, the code may be omitted as a pattern. Also, similar functions are used in similar places. Symbols may be used, and detailed explanations may be omitted.

[0348] The light-emitting elements 260a and 260b shown in Figures 5(A) and 5(B) are connected to the substrate 200 side. It may also be a bottom-emission type light-emitting element that extracts from the substrate 200 and It may also be a top-emission type light-emitting element that extracts light in the opposite direction. However, one aspect of the present invention is not limited thereto, and the light emitted by the light-emitting element is directed above the substrate 200. It may also be a dual-emission type light-emitting element that emits light from both the upper and lower sides. .

[0349] When the light-emitting element 260a and light-emitting element 260b are of the bottom emission type, electrode 1 Preferably, 01 has the function of transmitting light. Also, electrode 102 reflects light. It is preferable that the light-emitting element 260a and the light-emitting element 260b have a function. In the case of a top-emission type, it is preferable that the electrode 101 has the function of reflecting light. Furthermore, it is preferable that the electrode 102 has the function of transmitting light.

[0350] The light-emitting element 260a and the light-emitting element 260b have an electrode 101 and an electrode 102 on the substrate 200. It has the following: In addition, between electrode 101 and electrode 102, there is a light-emitting layer 123B and a light-emitting layer 123 It has G and a light-emitting layer 123R. It also has a hole injection layer 111 and a hole transport layer 112. It has an electron transport layer 118 and an electron injection layer 119.

[0351] Furthermore, the light-emitting element 260b is part of the configuration of the electrode 101, and the conductive layer 101a and the conductive It has a conductive layer 101b on layer 101a and a conductive layer 101c below the conductive layer 101a. In other words, the light-emitting element 260b has a conductive layer 101a, a conductive layer 101b, and a conductive layer 101c. It has a configuration of clamped electrodes 101.

[0352] In the light-emitting element 260b, the conductive layer 101b and the conductive layer 101c are made of different materials. It may be done in this way, or it may be formed from the same material. The electrode 101 may be sandwiched between the same conductive material. If the configuration is such that the pattern shape is formed by the etching process during the formation of the electrode 101 This is preferable because it makes the process easier.

[0353] Furthermore, in the light-emitting element 260b, in the conductive layer 101b or the conductive layer 101c, A configuration having only one of the two offsets is also acceptable.

[0354] Furthermore, the conductive layers 101a, 101b, and 101c of the electrode 101 are each implemented The same configuration and materials as those used for electrode 101 or electrode 102 shown in Form 1 can be used. Cut.

[0355] In Figures 5(A) and 5(B), the region 221B is sandwiched between electrode 101 and electrode 102. A partition wall 145 is located between region 221G and region 221R. The partition wall 145 provides insulation. The partition wall 145 covers the end of the electrode 101 and has an opening that overlaps with the electrode. By providing the wall 145, the electrodes 101 on the substrate 200 in each region are arranged in island-like formations. It becomes possible to separate them.

[0356] Furthermore, in the region where the light-emitting layer 123B and the light-emitting layer 123G overlap with the partition wall 145, They may have overlapping regions. Alternatively, the light-emitting layer 123G and the light-emitting layer 123R may have overlapping regions. In the region where it overlaps with the partition wall 145, it may have overlapping regions. In the region where the light-emitting layer 123R and the light-emitting layer 123B overlap with the partition wall 145, It may have an overlapping region.

[0357] The partition wall 145 only needs to be insulating and is formed using an inorganic or organic material. The inorganic materials include silicon oxide, silicon oxide nitride, silicon nitride oxide, silicon nitride silicon Examples of organic materials include aluminum oxide, aluminum nitride, etc. Examples include photosensitive resin materials such as acrylic resin or polyimide resin.

[0358] Furthermore, a silicon oxidizride film is a film whose composition contains more oxygen than nitrogen. Preferably, oxygen is 55 atomic% or more and 65 atomic% or less, and nitrogen is 1 atomic% or more and 20 atomic%. Below, silicon is 25 atomic% to 35 atomic%, and hydrogen is 0.1 atomic% to 10 atomic%. This refers to films that fall within the range below. A silicon nitride oxide film is a film whose composition contains more nitrogen than oxygen. This refers to a membrane with a high element content, preferably containing 55 atomic% or more and 65 atomic% or less of nitrogen, and 1 atomic% of oxygen. Atomic percent to 20 atomic percent, silicon 25 atomic percent to 35 atomic percent, hydrogen 0.1 atomic percent This refers to a film containing a substance in a concentration range of 10% to 10 atomic%.

[0359] Furthermore, the light-emitting layer 123R, light-emitting layer 123G, and light-emitting layer 123B each exhibit different colors. It is preferable to have a light-emitting material that has the function of emitting red light. For example, the light-emitting layer 123R exhibits red light. By having a light-emitting material that has the function of, region 221R exhibits red light emission, and light-emitting layer 12 Region 221G emits green light because region 3G has a light-emitting material that exhibits a green light. The light-emitting layer 123B has a light-emitting material that exhibits a blue color, thus region 221 B emits blue light. A light-emitting element 260a or light-emitting element 26 has such a configuration. By using 0b as the pixel of the display device, a display device capable of full-color display can be manufactured. This is possible. Also, the film thickness of each light-emitting layer may be the same or different. good.

[0360] Additionally, one or more of the light-emitting layers 123B, 123G, and 123R. The light-emitting layer is the light-emitting layer 130 shown in Embodiment 1 and the light-emitting layer 14 shown in Embodiment 4. It is preferable to have at least one of the configurations shown in Embodiment 2. It is preferable to have a lydium complex as the luminescent material. This results in good luminescence efficiency. It is possible to fabricate a light-emitting element.

[0361] Note that one or more of the light-emitting layers 123B, 123G, and 123R may be present. The light-emitting layer may be configured with two or more layers stacked on top of each other.

[0362] As described above, at least one light-emitting layer emits light as shown in Embodiments 1 and 4. A light-emitting element 26 having a layer configuration or the light-emitting material shown in Embodiment 2, and having the light-emitting layer. By using 0a or light-emitting element 260b as pixels in a display device, a display device with high luminous efficiency can be achieved. A device can be manufactured. That is, a device having a light-emitting element 260a or a light-emitting element 260b The display device can reduce power consumption.

[0363] Furthermore, in the direction from which light is extracted from the electrode that extracts light, an optical element (for example, a color filter) is placed. By providing polarizing plates, anti-reflective coatings, etc., the color purity of the light-emitting element 260a and the light-emitting element 260b is improved. The degree can be improved. Therefore, the light-emitting element 260a or light-emitting element 260b The color purity of the display device can be improved. Alternatively, the light-emitting element 260a and the light-emitting element can be improved. External light reflection of 260b can be reduced. Therefore, the light-emitting element 260a or light-emitting element The contrast ratio of a display device having sub-element 260b can be increased.

[0364] Furthermore, other configurations of the light-emitting element 260a and light-emitting element 260b are as follows: The configuration of the light-emitting element in Embodiment 1, Embodiment 4, and Embodiment 5 should be taken into consideration.

[0365] <Example of light-emitting element configuration 2> Next, Figures 6(A) and 6(B) show examples of configurations different from the light-emitting elements shown in Figures 5(A) and 5(B). We will use this to provide the following explanation.

[0366] Figures 6(A) and 6(B) are cross-sectional views showing a light-emitting element according to one embodiment of the present invention. In (B), the same symbols are used for parts that have the same function as those shown in Figures 5(A) and (B). A hatch pattern may be used, and the symbols may be omitted. Also, in areas with similar functions, Similar symbols may be used, and their detailed explanations may be omitted.

[0367] Figures 6(A) and 6(B) show examples of the configuration of a light-emitting element having a light-emitting layer between a pair of electrodes. The light-emitting element 262a shown in (A) is an upper-surface emitter that extracts light in the direction opposite to the substrate 200. The light-emitting element (a type of hop-emission light-emitting element), the light-emitting element 262b shown in Figure 6(B), is on the substrate 200 side. This is a bottom-emission type light-emitting element that extracts light from the bottom. One embodiment is not limited thereto, and the light emitted by the light-emitting element is on the substrate 200 on which the light-emitting element is formed. It may also be a dual-emission type that extracts material from both the front and the bottom.

[0368] The light-emitting element 262a and the light-emitting element 262b have an electrode 101 and an electrode 102 on the substrate 200. It has electrode 103 and electrode 104. Also, between electrode 101 and electrode 102, At least light is emitted between electrode 102 and electrode 103, and between electrode 102 and electrode 104. It has a layer 170, a light-emitting layer 190, and a charge-generating layer 115. It also has a hole injection layer 111 and , hole transport layer 112, electron transport layer 113, electron injection layer 114, hole injection layer 116 It has a hole transport layer 117, an electron transport layer 118, and an electron injection layer 119.

[0369] Furthermore, the electrode 101 consists of a conductive layer 101a and a conductive layer 101b that is in contact with the conductive layer 101a. , has . Furthermore, electrode 103 has a conductive layer 103a and a conductive layer in contact with the conductive layer 103a 103b and Electrode 104 has a conductive layer 104a and a conductive layer in contact with the conductive layer 104a. It has an electrolytic layer 104b.

[0370] The light-emitting element 262a shown in Figure 6(A) and the light-emitting element 262b shown in Figure 6(B) are electrodes Region 222B sandwiched between electrode 101 and electrode 102, sandwiched between electrode 102 and electrode 103 Between region 222G and region 222R sandwiched between electrode 102 and electrode 104, It has a wall 145. The partition wall 145 is insulating. The partition wall 145 has electrodes 101 and 1 03, and the end of electrode 104 are covered, and the partition wall 145 has an opening that overlaps with the electrode. By doing so, the electrodes on the substrate 200 in each region can be separated into island-like structures. It becomes Noh.

[0371] Furthermore, the charge generation layer 115 is made of a hole transport material to which electron acceptors are attached. By adding materials, or by adding electron donors to electron transport materials, It can be formed if the conductivity of the charge generation layer 115 is as high as that of the pair of electrodes. In addition, the carriers generated by the charge generation layer 115 flow to the adjacent pixels, and then to the adjacent pixels In some cases, the element may emit light unintentionally. Therefore, it is necessary to suppress the unauthorized emission of light from adjacent pixels. In order to achieve this, the charge generation layer 115 is formed of a material with lower conductivity than the pair of electrodes. preferable.

[0372] Furthermore, the light-emitting element 262a and the light-emitting element 262b are located in region 222B, region 222G, and In the direction from which the light emitted from region 222R is extracted, the optical element 224B and the optical element are respectively positioned. The substrate 220 has a sub-element 224G and an optical element 224R. Light emitted from each region It is emitted to the outside of the light-emitting element through each optical element. That is, it is emitted from region 222B. The light is emitted through the optical element 224B, and the light emitted from region 222G is emitted through the optical element The light emitted through 224G and emanating from region 222R is transmitted through optical element 224R. It is launched.

[0373] Furthermore, optical elements 224B, 224G, and 224R receive incident light It has the function of selectively transmitting light exhibiting a specific color. For example, optical element 224B The light emitted from region 222B through the optical element 22 becomes blue light. The light emitted from region 222G via 4G becomes green light, and the optical element The light emitted from region 222R via sub-element 224R is red in color.

[0374] Optical elements 224R, 224G, and 224B include, for example, a colored layer ( Color filters (also called color filters), bandpass filters, and multilayer filters can be applied. Furthermore, a color conversion element can be applied to an optical element. The color conversion element converts the incident light to... This is an optical element that converts light to wavelengths longer than the wavelength of the light in question. It uses quantum dots as color conversion elements. It is preferable to use an element that employs quantum dots. By using quantum dots, the color reproducibility of the display device can be improved. It can improve.

[0375] Furthermore, other optical elements may be placed on optical elements 224R, 224G, and 224B. One or more of these may be arranged in a stack. Other optical elements include, for example, circular polarizers and anti-reflective coatings. A protective film can be provided. The circular polarizing plate is used to extract light emitted from the light-emitting element of the display device. When placed on the receiving side, light incident from outside the display device is reflected inside the display device, and the outside This prevents the phenomenon of ejection from the part. In addition, by providing an anti-reflective coating, the surface of the display device This can reduce the amount of ambient light reflected by the device. This makes the light emitted by the display device clearer. It can be observed.

[0376] In Figures 6(A) and 6(B), the light emitted from each region through each optical element is referred to as blue. Let light exhibiting color (B), light exhibiting green (G), and light exhibiting red (R) be defined as follows: This is schematically illustrated with dashed arrows.

[0377] Furthermore, a light-shielding layer 223 is provided between each optical element. The light-shielding layer 223 is provided in adjacent regions or It has the function of blocking the light emitted from it. Furthermore, a configuration without the light-blocking layer 223 is also acceptable. stomach.

[0378] The light-shielding layer 223 has the function of suppressing the reflection of external light. Alternatively, the light-shielding layer 223 and Therefore, it has the function of preventing the mixing of colors of light emitted from adjacent light-emitting elements. Light-shielding layer 223 and For example, metals, resins containing black pigments, carbon black, metal oxides, and multiple metal oxides. A composite oxide containing a solid solution of a substance can be used.

[0379] Furthermore, optical element 224B and optical element 224G are in the region where they overlap with the light-shielding layer 223. They may have overlapping regions. Alternatively, optical element 224G and optical element 224R refers to the region in which the light-shielding layer 223 overlaps, even if there are overlapping regions between them. Good. Alternatively, optical element 224R and optical element 224B are superimposed on the light-shielding layer 223. Within a given domain, there may be overlapping regions.

[0380] Furthermore, the configuration of the substrate 200 and the substrate 220 having optical elements is as follows: Embodiment 1 You can take it into consideration.

[0381] Furthermore, the light-emitting elements 262a and 262b have a microcavity structure. .

[0382] <<Microcavity structure>> Light emitted from the light-emitting layer 170 and the light-emitting layer 190 is directed to a pair of electrodes (for example, electrode 10 Resonance occurs between 1 and electrode 102). Also, the light-emitting layer 170 and light-emitting layer 190 are emitted. It is formed at a position where the light of a desired wavelength is intensified among the incoming light. For example, in the reflection region of electrode 101 The optical distance from the light-emitting region of the light-emitting layer 170 to the optical distance from the reflection region of the electrode 102 to the light-emitting layer 170 By adjusting the optical distance to the light-emitting region, the light emitted from the light-emitting layer 170 can be controlled. This allows for the enhancement of light of a desired wavelength. Also, from the reflection region of electrode 101 to the light-emitting layer 190 The optical distance to the light-emitting region and the distance from the reflection region of electrode 102 to the light-emitting region of light-emitting layer 190. By adjusting the optical distance, the desired wavelength of light emitted from the light-emitting layer 190 can be selected. The light can be intensified. That is, multiple light-emitting layers (here, light-emitting layer 170 and light-emitting layer In the case of a light-emitting element that stacks 190), the optical distance between the light-emitting layer 170 and the light-emitting layer 190 is It is preferable to optimize the separation.

[0383] Furthermore, in the light-emitting element 262a and light-emitting element 262b, a conductive layer (conductive layer 1) is present in each region. By adjusting the thickness of 01b, conductive layer 103b, and conductive layer 104b), the light-emitting layer 170 Furthermore, it is possible to enhance the light of a desired wavelength from the light emitted from the light-emitting layer 190. In the region, at least one of the hole injection layer 111 and the hole transport layer 112 has a different thickness. This may enhance the light emitted from the light-emitting layer 170 and the light-emitting layer 190.

[0384] For example, electrodes 101 to 104 are made of a conductive material that has the function of reflecting light. When the refractive index is smaller than the refractive index of the light-emitting layer 170 or the light-emitting layer 190, the electrode The thickness of the conductive layer 101b on 101 is determined by the optical distance between electrode 101 and electrode 102 being m B λ B / 2(m B λ is a natural number, B(These represent the wavelengths of light that are strengthened in region 222B.) Adjust to achieve this. Similarly, the thickness of the conductive layer 103b on electrode 103 is adjusted to match electrode 103 and The optical distance between electrode 102 is m G λ G / 2(m G λ is a natural number, G Stronger in region 222G The wavelengths of light are adjusted to be (represented by). Furthermore, the conductive layer of electrode 104 The film thickness of 104b is such that the optical distance between electrode 104 and electrode 102 is m R λ R / 2(m R is natural number, λ R The wavelengths of light that are strengthened in region 222R are adjusted accordingly.

[0385] Furthermore, if it is difficult to precisely determine the reflection region of electrodes 101 to 104, By assuming that any region of electrode 101 to electrode 104 is a reflective region, the light-emitting layer 170 or The optical distance at which the light emitted from the light layer 190 is intensified may be derived. Also, the light-emitting layer 170 If it is difficult to precisely determine the light-emitting region of the light-emitting layer 190, the light-emitting layer 170 and By assuming that any region of the light layer 190 is an emission region, the emission layer 170 and the emission layer 190 You may also derive the optical distance at which the light emitted from the source is intensified.

[0386] As described above, a microcavity structure is provided, and the optical distance between the pair of electrodes in each region is adjusted. By optimizing the surface, light scattering and absorption near each electrode are suppressed, resulting in a high light extraction efficiency. It is possible to achieve this rate.

[0387] In the above configuration, conductive layer 101b, conductive layer 103b, and conductive layer 104b are light It is preferable that the conductive layer 101b, conductive layer 103b, and conductive The materials constituting layer 104b may be the same or different. When the same material is used for the electrical layer 101b, the conductive layer 103b, and the conductive layer 104b, electrode 10 1. Pattern formation by etching process during the formation of electrodes 103 and 104 is acceptable. This is preferable because it makes things easier. Also, conductive layers 101b, 103b, and 104b are Each layer may have a configuration consisting of two or more layers stacked on top of each other.

[0388] Note that the light-emitting element 262a shown in Figure 6(A) is a top-export type light-emitting element, therefore it is conductive Layer 101a, conductive layer 103a, and conductive layer 104a have the function of reflecting light. Preferably, the electrode 102 has both the function of transmitting light and the function of reflecting light. It is preferable.

[0389] Furthermore, the light-emitting element 262b shown in Figure 6(B) is a bottom-extrusion type light-emitting element, therefore it is conductive Layer 101a, conductive layer 103a, and conductive layer 104a have the function of transmitting light and the function of reflecting light. It is preferable that the electrode 102 has the ability to reflect light. preferable.

[0390] Furthermore, in the light-emitting element 262a and light-emitting element 262b, conductive layer 101a, conductive layer 10 The same material may be used for 3a or the conductive layer 104a, or different materials may be used. When the same material is used for conductive layer 101a, conductive layer 103a, and conductive layer 104a, the light-emitting element The manufacturing costs of the sub-element 262a and the light-emitting element 262b can be reduced. The electrical layer 103a and the conductive layer 104a may each have a configuration in which two or more layers are stacked. stomach.

[0391] Furthermore, the light-emitting layers 170 and 190 in the light-emitting elements 262a and 262b At least one of the configurations shown in Embodiment 1 and Embodiment 4 is included. It is preferable to have the iridium complex shown in Embodiment 2 as the luminescent material. It is preferable to do so. By doing so, it is possible to create a light-emitting element that exhibits high luminescence efficiency. ru.

[0392] Furthermore, the light-emitting layer 170 and the light-emitting layer 190 are, for example, light-emitting layer 190a and light-emitting layer 190b Thus, a configuration in which two layers are stacked on one or both sides may be used. The two light-emitting layers include the first Two types of light-emitting materials, a compound and a second compound, which have the function of exhibiting different colors, are used. By using them, it is possible to obtain light emission containing multiple colors. In particular, the light emission layer 170 and the light emission The luminescent material used in each luminescent layer is selected so that the light emitted by layer 190 results in a white color. It would be preferable if that were the case.

[0393] Furthermore, the light-emitting layer 170 or the light-emitting layer 190 has a structure in which three or more layers are stacked, either one or both. It may be a composite material, and may also include a layer that does not contain luminescent material.

[0394] As described above, the configuration of the light-emitting layer shown in Embodiment 1 and Embodiment 4 is at least one By using the light-emitting element 262a or light-emitting element 262b as a pixel of a display device, A display device with high light efficiency can be fabricated. That is, the light-emitting element 262a or the light-emitting element A display device having element 262b can reduce power consumption.

[0395] Regarding the other configurations of the light-emitting element 262a and light-emitting element 262b, 260a or light-emitting element 260b, or Embodiment 1, Embodiment 4, and the form of the embodiment You should refer to the configuration of the light-emitting element shown in Form 5.

[0396] <Method for fabricating a light-emitting element> Next, a method for manufacturing a light-emitting element according to one aspect of the present invention will be described below with reference to Figures 7 and 8. This will be done. Here, we will explain the method for fabricating the light-emitting element 262a shown in Figure 6(A). ru.

[0397] Figures 7 and 8 are cross-sectional views illustrating a method for manufacturing a light-emitting element according to one aspect of the present invention. .

[0398] The method for fabricating the light-emitting element 262a described below comprises seven steps, from the first to the seventh. ru.

[0399] ≪Step 1≫ The first step is to create electrodes for the light-emitting element (specifically, conductive layers 101 that constitute the electrodes 101). a) conductive layer 103a constituting electrode 103, and conductive layer 104a constituting electrode 104) This is the process of forming it on the substrate 200 (see Figure 7(A)).

[0400] In this embodiment, a conductive layer having the function of reflecting light is formed on the substrate 200. By processing the conductive layer into a desired shape, conductive layer 101a, conductive layer 103a, and conductive Layer 104a is formed. The conductive layer having the function of reflecting light is made of silver and palladium. A copper alloy film (also called Ag-Pd-Cu film or APC) is used. The process of processing the same conductive layer to form the electrical layer 101a, conductive layer 103a, and conductive layer 104a This method is preferable because it allows for lower manufacturing costs.

[0401] Note that before the first step, multiple transistors may be formed on the substrate 200. Furthermore, the plurality of transistors, conductive layer 101a, conductive layer 103a, and conductive layer 104a They may be electrically connected to each other.

[0402] ≪Step 2≫ The second step is to have a light-transmitting function on the conductive layer 101a that constitutes the electrode 101. A conductive layer 101b is placed on the conductive layer 103a constituting the electrode 103, and has the function of transmitting light. A conductive layer 103b is placed on the conductive layer 104a constituting the electrode 104, and has the function of transmitting light. This is the step of forming the conductive layer 104b (see Figure 7(B)).

[0403] In this embodiment, conductive layers 101a, 103a, and have the function of reflecting light, On 104a, there are conductive layers 101b, 103b, and respectively, which have the function of transmitting light. By forming 104b, electrodes 101, 103, and 104 are formed. ITSO films are used as the conductive layers 101b, 103b, and 104b.

[0404] Furthermore, the conductive layers 101b, 103b, and 104b, which have the function of transmitting light, can be used multiple times. It may be formed in stages. By forming it in stages, suitable microcaches can be formed in each region. The conductive layers 101b, 103b, and 104b can be formed with a film thickness that creates a vitreous structure. Cut.

[0405] ≪Step 3≫ The third step is to form partition walls 145 that cover the ends of each electrode of the light-emitting element. See Figure 7(C).

[0406] The partition wall 145 has an opening that overlaps with the electrode. The conductive film exposed by the opening. This functions as the anode of the light-emitting element. In this embodiment, the partition wall 145 is made of polyimide resin. Use fat.

[0407] Furthermore, in steps 1 to 3, the EL layer (the layer containing organic compounds) is damaged. Because there is no risk, various film formation methods and microfabrication techniques can be applied. This involves forming a reflective conductive layer using a sputtering method, and then using a lithography method to... A pattern is formed on the electrode layer, and then a dry etching method or a wet etching method is used. Then, by processing the conductive layer into an island shape, the conductive layer 101a and electrode 10 constitute the electrode 101. A conductive layer 103a constituting 3 and a conductive layer 104a constituting electrode 104 are formed. Subsequently, a transparent conductive film is deposited using the sputtering method, and then lithography is used. Then, a pattern is formed on the transparent conductive film, and then a wet etching method is used. Then, the transparent conductive film is processed into an island shape to form electrodes 101, 103, and 10 Form 4.

[0408] ≪Step 4≫ The fourth step involves a hole injection layer 111, a hole transport layer 112, a light-emitting layer 190, and an electron transport layer. This is a step to form 113, an electron injection layer 114, and a charge generation layer 115 (see Figure 8(A)). (see).

[0409] As the hole injection layer 111, a material containing a hole transporting material and an acceptor material is co-evaporated. It can be formed by deposition. Co-deposition is the process of depositing multiple different materials together. This is a vapor deposition method in which evaporation occurs simultaneously from an evaporation source. In addition, the hole transport layer 112 is a hole It can be formed by depositing a transportable material.

[0410] The light-emitting layer 190 can be purple, blue, blue-green, green, yellow-green, yellow, orange, or red. This is formed by depositing at least one luminescent guest material selected from among them. This can be done. As guest materials, luminescent organic compounds that exhibit fluorescence or phosphorescence can be used. This is possible. Furthermore, by using the light-emitting layer configuration shown in Embodiment 1 and Embodiment 4, This is preferable. Alternatively, the light-emitting layer 190 may have a two-layer configuration. In that case, the two layers of light-emitting layer Preferably, the light layer has light-emitting materials that each exhibit a different emission color.

[0411] The electron transport layer 113 can be formed by depositing a material with high electron transport properties. It is possible. Furthermore, the electron injection layer 114 is formed by depositing a material with high electron injection properties. It is possible.

[0412] As the charge generation layer 115, electron acceptors are added to a hole transport material. Deposition of a material, or a material to which an electron donor has been added to an electron transport material. It can be formed with.

[0413] ≪Step 5≫ The fifth step involves a hole injection layer 116, a hole transport layer 117, a light-emitting layer 170, and an electron transport layer. This is a step in which 118, the electron injection layer 119, and the electrode 102 are formed (see Figure 8(B)).

[0414] The hole injection layer 116 is made of the same material and is made using the same method as the hole injection layer 111 described above. It can be formed more easily. Also, as the hole transport layer 117, the hole transport layer 11 shown above It can be formed using the same materials and methods as in 2.

[0415] The light-emitting layer 170 can be purple, blue, blue-green, green, yellow-green, yellow, orange, or red. This is formed by depositing at least one luminescent guest material selected from among them. This can be done. As guest materials, luminescent organic compounds that exhibit fluorescence or phosphorescence can be used. This is possible. Furthermore, by using the light-emitting layer configuration shown in Embodiment 1 and Embodiment 4, Preferably, at least one of the light-emitting layer 170 and the light-emitting layer 190 is as in Embodiment 1. It is preferable to have the configuration of the light-emitting layer shown in Embodiment 4. Also, the light-emitting layer 170 and The light-emitting layer 190 has light-emitting organic compounds that have the function of exhibiting different types of light emission from each other. preferable.

[0416] The electron transport layer 118 is made of the same material and is constructed using the same method as the electron transport layer 113 described above. It can be formed more easily. Also, as the electron injection layer 119, the electron injection layer 11 shown above It can be formed using the same materials and methods as in 4.

[0417] The electrode 102 consists of a reflective conductive film and a translucent conductive film laminated together. It can be formed as follows. Also, the electrode 102 can be a single-layer structure or a multi-layer structure. That's good too.

[0418] After the above process, regions 222 are formed on electrodes 101, 103, and 104, respectively. A light-emitting element having region B, region 222G, and region 222R is formed on the substrate 200.

[0419] Step 6 The sixth step is to place a light-shielding layer 223, optical element 224B, and optical element 224 on the substrate 220. This is the process of forming G and the optical element 224R (see Figure 8(C)).

[0420] As the light-shielding layer 223, a resin film containing black pigment is formed in the desired area. After that, the base On the plate 220 and the light-shielding layer 223, optical element 224B, optical element 224G, and optical element 2 Forming 24R. As the optical element 224B, a resin film containing blue pigment is applied to the desired region. Formed. In addition, as the optical element 224G, a resin film containing green pigment is formed in a desired region. Furthermore, as the optical element 224R, a resin film containing red pigment is formed in the desired region. do.

[0421] ≪Step 7≫ The seventh step is to have a light-emitting element formed on substrate 200 and a light-emitting element formed on substrate 220 The light-shielding layer 223, optical element 224B, optical element 224G, and optical element 224R are attached. This is the process of sealing the parts together using a sealing material (not shown in the diagram).

[0422] By following the above steps, the light-emitting element 262a shown in Figure 6(A) can be formed.

[0423] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible to be there.

[0424] (Embodiment 7) In this embodiment, a display device according to one aspect of the present invention will be described using Figures 9 to 17. do.

[0425] <Example of display device configuration 1> Figure 9(A) is a top view showing the display device 600, and Figure 9(B) is a view of Figure 9(A) along the dashed line AB. , and a cross-sectional view taken along the dashed line CD. The display device 600 is a drive circuit section (signal line It has a drive circuit section 601, a scan line drive circuit section 603, and a pixel section 602. The signal line drive circuit section 601, the scan line drive circuit section 603, and the pixel section 602 are light-emitting elements. It has a function to control light emission.

[0426] Furthermore, the display device 600 includes an element substrate 610, a sealing substrate 604, and a sealing material 605. The area 607 surrounded by the sealing material 605, the routed wiring 608, and the FPC 609 are all included. do.

[0427] Furthermore, the routing wiring 608 is connected to the signal line drive circuit section 601 and the scan line drive circuit section 603. This is wiring for transmitting input signals, and it connects to the FPC609, which is an external input terminal, for video input. It receives signals such as the O signal, clock signal, start signal, and reset signal. Note that here it is FP Only C609 is shown in the diagram, but FPC609 is a printed circuit board (PWB: Pri A wired wiring board may be attached.

[0428] Furthermore, the signal line drive circuit section 601 consists of an N-channel type transistor 623 and a P-channel type A CMOS circuit is formed by combining it with transistor 624. The path section 601 or the scan line drive circuit section 603 includes various CMOS circuits, PMOS circuits, and An NMOS circuit can be used. In addition, in this embodiment, the drive circuit section is mounted on the substrate. The image shows a display device in which the formed driver and pixels are arranged on the same surface, but this is not necessarily required. Alternatively, the drive circuit can be formed externally instead of on the circuit board.

[0429] Furthermore, the pixel section 602 includes a switching transistor 611 and a current control transistor. The lower part electrically connected to the drain of transistor 612 for current control and transistor 612 It has an electrode 613. A partition wall 614 is formed to cover the end of the lower electrode 613. A positive-type photosensitive acrylic resin film can be used as the partition wall 614.

[0430] Furthermore, in order to improve coverage, the upper or lower end of the partition wall 614 has a curved surface with curvature. To ensure that a structure is formed. For example, positive-type photosensitive acrylic is used as the material for the partition wall 614. If so, the upper end of the partition wall 614 will have a curve with a radius of curvature (0.2 μm or more and 3 μm or less). It is preferable to give it a surface. Also, as the partition wall 614, a negative type photosensitive resin or a poly Any type of photosensitive resin can be used.

[0431] Furthermore, the structure of the transistors (transistors 611, 612, 623, 624) is particularly... It is not limited. For example, a staggered transistor may be used. Also, the transistor There are no particular limitations regarding polarity, and it includes N-channel and P-channel transistors. A structure that includes either an N-channel transistor or a P-channel transistor. A structure consisting of only one of the two may also be used. Furthermore, the semiconductor film crystal used in transistors... There are no particular limitations regarding properties. For example, amorphous semiconductor films and crystalline semiconductor films can be used. Yes, it is possible. Also, as semiconductor materials, there are Group 14 (silicon, etc.) semiconductors and compound semiconductors (oxides). Semiconductors (including organic semiconductors), etc., can be used. Examples of transistors include: Energy gap of 2 eV or more, preferably 2.5 eV or more, more preferably 3 eV By using the above oxide semiconductors, the off-current of the transistor can be reduced. Preferably, the oxide semiconductor is In-Ga oxide, In-M-Zn oxide (M is Aluminum (Al), gallium (Ga), yttrium (Y), zirconium (Zr ), lanthanum (La), cerium (Ce), tin (Sn), hafnium (Hf), or ne Examples include odymium (Nd).

[0432] An EL layer 616 and an upper electrode 617 are formed on the lower electrode 613, respectively. The lower electrode 613 functions as the anode, and the upper electrode 617 functions as the cathode. ru.

[0433] Furthermore, the EL layer 616 can be coated using a deposition method with a deposition mask, an inkjet method, or a spin coat. It is formed by various methods such as the law. In addition, the material that constitutes the EL layer 616 is low It may be a molecular compound or a polymeric compound (including oligomers and dendrimers).

[0434] Furthermore, the lower electrode 613, the EL layer 616, and the upper electrode 617 contribute to the light-emitting element 618. The light-emitting element 618 is formed according to the configuration of Embodiment 1, Embodiment 4 to Embodiment 6. It is preferable that the light-emitting element has multiple elements. The light-emitting element described in Embodiment 1, Embodiments 4 to 6, and other configurations are provided. It may include both the light-emitting element and the light-emitting element.

[0435] Furthermore, by bonding the sealing substrate 604 to the element substrate 610 with the sealing material 605, A light-emitting element is placed in the region 607 surrounded by the element substrate 610, the sealing substrate 604, and the sealing material 605. The structure is equipped with child 618. Furthermore, the area 607 is filled with filler material. In addition to cases where an inert gas (such as nitrogen or argon) is filled, it is also used in sealant 605. In some cases, it may be filled with UV-curing resin or thermosetting resin, for example, PVC ( Polyvinyl chloride resins, acrylic resins, polyimide resins, epoxy resins, Silicone resin, PVB (polyvinyl butyral) resin, or EVA (ethylene vinyl A resin (such as a luacetate) can be used. A recess is formed in the sealing substrate, and a desiccant is placed therein. Providing this feature can suppress deterioration due to moisture, making it a desirable configuration.

[0436] Furthermore, the optical element 621 is positioned below the sealing substrate 604 so as to overlap with the light-emitting element 618. It is provided therein. Furthermore, a light-shielding layer 622 is provided below the sealing substrate 604. Optical element 621 and the light-shielding layer 622 are the optical element and the light-shielding layer shown in Embodiment 6, respectively. A similar configuration would suffice.

[0437] Furthermore, it is preferable to use epoxy resin or glass frit for the sealant 605. Furthermore, it is desirable that these materials be as impermeable to moisture and oxygen as possible. In addition, as materials used for the sealing substrate 604, glass substrates and quartz substrates are also available, as well as FRP (Fiber Reinforced Plastic). Reinforced Plastics), PVF (Polyvinyl Fluoride), Poly A plastic substrate made of ester or acrylic can be used.

[0438] As described above, the light-emitting element described in Embodiments 1, 4 to 6 and A display device having optical elements can be obtained.

[0439] <Example of display device configuration 2> Next, another example of a display device will be explained using Figures 10(A)(B) and 11. Figures 10(A)(B) and 11 are cross-sectional views of a display device according to one embodiment of the present invention. .

[0440] Figure 10(A) shows the substrate 1001, the underlayer insulating film 1002, the gate insulating film 1003, and the gate Electrodes 1006, 1007, 1008, first interlayer insulating film 1020, second interlayer insulating film 10 21, peripheral portion 1042, pixel portion 1040, drive circuit portion 1041, lower electrode 10 of light-emitting element 24R, 1024G, 1024B, partition wall 1025, EL layer 1028, upper electrode of light-emitting element 1026, the sealing layer 1029, the sealing substrate 1031, the sealing material 1032, etc. are shown in the diagram. .

[0441] Furthermore, in Figure 10(A), as an example of an optical element, a colored layer (red colored layer 1034R, A green colored layer 1034G and a blue colored layer 1034B are provided on a transparent substrate 1033. A light-shielding layer 1035 may also be provided. A transparent material having a colored layer and a light-shielding layer. The substrate 1033 is aligned and fixed to the substrate 1001. Note that the colored layer and the light-shielding layer are also included. It is covered with an overcoat layer 1036. Also, in Figure 10(A), the colored layer Since light passing through it is red, green, and blue, an image can be represented using pixels of these three colors.

[0442] Figure 10(B) shows an example of an optical element, with a colored layer (red colored layer 1034R, green colored layer The colored layer 1034G and the blue colored layer 1034B are connected to the gate insulating film 1003 and the first interlayer insulating film. An example of formation between film 1020 and the substrate 1001 is shown. In this way, the colored layer is sealed with the substrate 1001. It may also be provided between the substrates 1031.

[0443] Figure 11 shows an example of an optical element, with a colored layer (red colored layer 1034R, green colored layer) 1034G, the blue colored layer 1034B) is connected to the first interlayer insulating film 1020 and the second interlayer insulating film This shows an example of formation between 1021 and substrate 1001. Thus, the colored layer is formed between substrate 1001 and the sealing group It may also be provided between the plates 1031.

[0444] Furthermore, in the display device described above, the side of the substrate 1001 on which the transistor is formed Although a display device with a light extraction structure (bottom emission type) was used, on the encapsulating substrate 1031 side It can also be used as a display device with a structure that extracts light (top emission type).

[0445] <Example of display device configuration 3> An example of a cross-sectional view of a top-emission type display device is shown in Figure 12(A)(B). Figure 12 Figures (A) and (B) are cross-sectional views illustrating a display device according to one embodiment of the present invention. ) and the drive circuit section 1041, peripheral section 1042, etc. shown in Figure 11 are omitted for illustrative purposes.

[0446] In this case, the substrate 1001 can be a substrate that does not transmit light. Until the connecting electrode that connects to the anode of the optical element is fabricated, it will be a bottom-emission type display device. It is formed in the same manner as above. Then, the third interlayer insulating film 1037 is formed so as to cover the electrode 1022. This insulating film may also play a planarization role. The third interlayer insulating film 1037 is In addition to materials similar to those used for the interlayer insulating film in step 2, it can be formed using a variety of other materials.

[0447] The lower electrodes 1024R, 1024G, and 1024B of the light-emitting element are referred to as anodes here, but the negative electrodes are not. It can also be a pole. Also, a top-emission type display like Figure 12(A)(B) is also acceptable. If it is a device, the lower electrodes 1024R, 1024G, and 1024B have the function of reflecting light. It is preferable to do so. Also, an upper electrode 1026 is provided on the EL layer 1028. Electrode 1026 has the function of reflecting light and the function of transmitting light, and lower electrode 1024R, 10 A microcavity structure is employed between 24G, 1024B and the upper electrode 1026. It is preferable to increase the light intensity at a specific wavelength.

[0448] In the top emission structure shown in Figure 12(A), the colored layer (red colored layer 1034) Encapsulation substrate 1031 provided with R, a green colored layer 1034G, and a blue colored layer 1034B) Sealing can be performed using this method. The sealing substrate 1031 is positioned between pixels. A light layer 1035 may be provided. Furthermore, if a light-transmitting substrate is used for the sealing substrate 1031, It is suitable.

[0449] Furthermore, in Figure 12(A), multiple light-emitting elements are shown, and each of these light-emitting elements is colored. While a configuration with layers has been given as an example, the system is not limited to this. For example, as shown in Figure 12(B) Without providing a green colored layer, a red colored layer 1034R and a blue colored layer 1034B are provided. Alternatively, a configuration that displays in full color using three colors—red, green, and blue—can be used. (See Figure 12(A)) Thus, when each light-emitting element is provided with a colored layer, external light reflection can be suppressed. This produces the desired effect. On the other hand, as shown in Figure 12(B), a green colored layer is provided on the light-emitting element. If a configuration is provided that includes a red colored layer and a blue colored layer, the light emitted from the green light-emitting element will be Because there is less energy loss from the emitted light, it has the effect of reducing power consumption. .

[0450] <Example of display device configuration 4> The display device described above has a configuration having subpixels of three colors (red, green, and blue), A structure having subpixels of four colors (red, green, blue, yellow, or red, green, blue, white) It may be considered as a component. Figures 13 to 15 show the lower electrodes 1024R, 1024G, 1024B, And the configuration of a display device having 1024Y. Figures 13(A)(B) and 14 show the tra A structure (bottom emission type) that extracts light from the substrate 1001 where the inverter is formed. This is a display device, and Figures 15(A) and 15(B) show a structure that extracts light from the encapsulated substrate 1031 side. It is a top-emission type display device.

[0451] Figure 13(A) shows the optical elements (colored layer 1034R, colored layer 1034G, colored layer 1034B This is an example of a display device in which a colored layer (1034Y) is provided on a transparent substrate (1033). Also, Figure 13 (B) is an optical element (colored layer 1034R, colored layer 1034G, colored layer 1034B, colored layer An indication of forming 1034Y) between the gate insulating film 1003 and the first interlayer insulating film 1020. This is an example of the apparatus. Also, Figure 14 shows the optical elements (colored layer 1034R, colored layer 1034G, The color layer 1034B and the colored layer 1034Y are connected to the first interlayer insulating film 1020 and the second interlayer insulating film 1 This is an example of a display device formed between 021 and 021.

[0452] Colored layer 1034R transmits red light, colored layer 1034G transmits green light, colored layer 1034B has the function of transmitting blue light. In addition, the colored layer 1034Y transmits yellow light. A function that allows light to pass through, or a function that transmits multiple colors selected from blue, green, yellow, and red. The colored layer 1034Y transmits multiple lights selected from blue, green, yellow, and red. When it has the function of being yellow, the light transmitted through the colored layer 1034Y may be white. Because light-emitting elements that emit white light have high luminous efficiency, a display having a colored layer 1034Y The device can reduce power consumption.

[0453] Furthermore, in the top-emission type display device shown in Figure 15, the lower electrode 1024Y In the light-emitting element having the same lower electrode 1024R as in the display device in Figure 12(A), Between 1024G, 1024B, 1024Y and the upper electrode 1026, a microcavity A configuration having a structure is preferred. Also, in the display device shown in Figure 15(A), the colored layer (red colored layer Color layer 1034R, green colored layer 1034G, blue colored layer 1034B, and yellow colored layer Sealing can be performed using a sealing substrate 1031 provided with 1034Y).

[0454] The emission exhibited through the microcavity and the yellow colored layer 1034Y is in the yellow region. The emission will have an emission spectrum in the region. Since yellow is a color with high visual sensitivity, yellow emission will occur. A light-emitting element exhibiting this characteristic has high luminous efficiency. That is, a display device having the configuration shown in Figure 15(A) is This can reduce power consumption.

[0455] Furthermore, in Figure 15(A), multiple light-emitting elements are shown, and each of these light-emitting elements is colored. While a configuration with layers has been given as an example, the system is not limited to this. For example, as shown in Figure 15(B) Without providing a yellow colored layer, a red colored layer 1034R, a green colored layer 1034G, and a blue colored layer are provided. A colored layer 1034B is provided, and four colors are used: red, green, blue, and yellow, or red, green, blue, and white. A configuration that enables full-color display may also be used. As shown in Figure 15(A), a light-emitting element and the When a colored layer is provided on each optical element, it has the effect of suppressing external light reflection. It performs. On the other hand, as shown in Figure 15(B), the light-emitting element and the red without a yellow colored layer are used. If the configuration includes a colored layer, a green colored layer, and a blue colored layer, then yellow or white Because there is little energy loss from the light-emitting element, power consumption can be reduced. It produces the desired effect.

[0456] <Example of display device configuration 5> Next, another embodiment of the present invention is shown in Figure 16. Figure 16 is a representation of Figure 9(A). This is a cross-sectional view taken along the dashed lines AB and CD. Note that in Figure 16... Parts having the same function as those shown in Figure 9(B) are denoted with the same symbols, and their detailed explanations are provided below. The "Akira" part will be omitted.

[0457] The display device 600 shown in Figure 16 comprises an element substrate 610, a sealing substrate 604, and a sealing material 60 The region 607 enclosed by 5 has sealing layers 607a, 607b, and 607c. One or more of the sealing layers 607a, 607b, and 607c may include, for example, For example, PVC (polyvinyl chloride) resin, acrylic resin, polyimide resin, etc. Poxy resins, silicone resins, PVB (polyvinyl butyral) resins, or EVA Resins such as (ethylene vinyl acetate) resins can be used. Also, silica oxide Silicon oxide nitride, silicon nitride, silicon nitride, aluminum oxide, aluminum nitride Inorganic materials such as titanium may also be used. Sealing layer 607a, sealing layer 607b, sealing layer 607 By forming c, the degradation of the light-emitting element 618 due to impurities such as water can be suppressed. Preferred. When forming sealing layer 607a, sealing layer 607b, and sealing layer 607c, It is not necessary to provide the 605 material.

[0458] Furthermore, sealing layers 607a, 607b, and 607c may be one or two of each. It may be the case that four or more sealing layers are formed. By making the sealing layers multilayered, water These impurities can penetrate from outside the display device 600 to the light-emitting element 618 inside the display device. This is preferable because it can effectively prevent this. Furthermore, if the sealing layer is multilayered, the resin and inorganic material A preferred configuration involves layering the materials.

[0459] <Example of display device configuration 6> Furthermore, the display devices shown in Configuration Examples 1 to 4 of this embodiment have optical elements. Although the above configuration has been illustrated, in one aspect of the present invention, optical elements may not be provided.

[0460] The display device shown in Figures 17(A) and 17(B) has a structure that extracts light from the encapsulated substrate 1031 side. This is a display device of the emitting type. Figure 17(A) shows the emitting layer 1028R and the emitting layer 1 This is an example of a display device having 028G and a light-emitting layer 1028B. Also, Figure 17(B) shows A table having a light layer 1028R, an emissive layer 1028G, an emissive layer 1028B, and an emissive layer 1028Y. This is an example of a display device.

[0461] The light-emitting layer 1028R emits red light, and the light-emitting layer 1028G emits green light. The light-emitting layer 1028B has the function of emitting blue light. The light-emitting layer 1028Y emits yellow light. A function that emits light, or a function that emits multiple lights selected from blue, green, and red. It has. The light emitted by the light-emitting layer 1028Y may be white. Yellow or white Because the light-emitting element has high luminous efficiency, a display device having the light-emitting layer 1028Y is It can reduce power consumption.

[0462] The display devices shown in Figures 17(A) and 17(B) include an EL layer that emits light of different colors. Since it is contained within the pixel, it is not necessary to provide a colored layer that acts as an optical element.

[0463] Furthermore, the sealing layer 1029 may be made of, for example, PVC (polyvinyl chloride) resin, acrylic Polyimide resins, epoxy resins, silicone resins, PVB (polyvinyl blue resin) Using resins such as ethylene vinyl acetate (EVA) resin or ethylene vinyl acetate resin. It is possible to do this. Also, silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride Inorganic materials such as aluminum oxide and aluminum nitride may also be used. The sealing layer 1029 Forming it this way is preferable because it can suppress the deterioration of the light-emitting element due to impurities such as water.

[0464] Furthermore, the sealing layer 1029 may consist of one or two of any four or more sealing layers. A layer may be formed. By making the sealing layer multilayered, impurities such as water can enter the outside of the display device. This is preferable because it can effectively prevent penetration into the interior of the display device. In the case of a multilayer structure, a preferred configuration is one in which resin and inorganic material are laminated together.

[0465] Furthermore, the encapsulating substrate 1031 only needs to have a function to protect the light-emitting element. Therefore, a flexible substrate or film can be used for the sealing substrate 1031.

[0466] Note that the configuration shown in this embodiment may be appropriately combined with other embodiments or other configurations within this embodiment. They can be combined.

[0467] (Embodiment 8) In this embodiment, a display device having an light-emitting element according to one aspect of the present invention is shown in Figures 18 to Figure 20 will be used for explanation.

[0468] Figure 18(A) is a block diagram illustrating a display device according to one embodiment of the present invention, and Figure 1 8(B) is a circuit diagram illustrating a pixel circuit in a display device according to one aspect of the present invention.

[0469] <Explanation regarding display devices> The display device shown in Figure 18(A) has a region having pixels of the display element (hereinafter referred to as the pixel portion 802 and ( ) and a circuit section ( ) which is located outside the pixel section 802 and has a circuit for driving the pixels. Hereinafter referred to as the drive circuit section 804, and a circuit having a function to protect the element (hereinafter referred to as the protection circuit 804) It has a (6) and a terminal section 807. Note that the protection circuit 806 is not provided. That's fine.

[0470] Part or all of the drive circuit section 804 is formed on the same substrate as the pixel section 802. This is desirable. This allows for a reduction in the number of components and terminals. Drive circuit section 804 If part or all of it is not formed on the same substrate as the pixel section 802, the drive cycle Part or all of road section 804 is COG or TAB (Tape Automated B It can be implemented by (onding).

[0471] The pixel section 802 is arranged in X rows (where X is a natural number greater than or equal to 2) and Y columns (where Y is a natural number greater than or equal to 2). It has a circuit for driving multiple display elements (hereinafter referred to as the pixel circuit 801), and the drive cycle The path section 804 is a circuit that outputs a signal (scan signal) for selecting pixels (hereinafter referred to as the scan line drive circuit). 804a) is used to supply signals (data signals) for driving the pixel display elements. It has a drive circuit such as the signal line drive circuit 804b.

[0472] The scan line driving circuit 804a includes a shift register, etc. The scan line driving circuit 804a is A signal to drive the shift register is input via terminal 807, and the signal is output. For example, the scan line drive circuit 804a receives a start pulse signal, a clock signal, etc. The scan line drive circuit 804a outputs a pulse signal. The scanning signal is supplied to the wiring (and It has the function of controlling the potential of the scan lines (referred to as GL_1 to GL_X). Multiple drive circuits 804a are provided, and the scan line GL_1 is driven by multiple scan line drive circuits 804a. The path to GL_X may be divided and controlled. Alternatively, the scan line drive circuit 804a may use an initialization signal. It has the function of supplying, however, the scan line drive circuit 80 4a can also supply another signal.

[0473] The signal line drive circuit 804b includes a shift register, etc. The signal line drive circuit 804b is Through terminal 807, in addition to signals for driving the shift register, the data signals are generated. A signal (image signal) is input. The signal line drive circuit 804b uses the image signal to drive the pixel circuit It has the function of generating data signals to be written to 801. In addition, the signal line drive circuit 804b The data signal is transmitted according to the pulse signal ob...

Claims

[Claim 1] A light-emitting element comprising a first organic compound, a second organic compound, and a guest material, The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than the HOMO level of the second organic compound. The LUMO level of the guest material is higher than the LUMO level of the first organic compound. The HOMO level of the guest material is lower than the HOMO level of the second organic compound. The aforementioned guest material has the function of converting triplet excitation energy into light emission, A light-emitting element, wherein the first organic compound and the second organic compound form an excited complex.

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