Organic light emitting element and display device using same

Abstract

The present disclosure provides an organic light-emitting element including a first electrode, a second electrode, and an organic compound layer disposed between the first electrode and the second electrode, and characterized in that: the organic compound layer includes a light-emitting layer; the light-emitting layer contains at least a first organic compound, a second organic compound, and a light-emitting compound that emits phosphorescence. The lowest excitation triplet energy of the first organic compound and the lowest excitation triplet energy of the second organic compound are higher than the lowest excitation triplet energy of the luminescent compound; and, for the first organic compound and the second organic compound, all freely rotatable single bonds are carbon-carbon bonds and satisfy the relationship of formula (1): HOMO (H2) gt; hOMO (H1) (1).

Description

Technical Field

[0001] The present invention relates to an organic light emitting element and a display device using the same. Background Art

[0002] An organic electroluminescent element (hereinafter also referred to as an "organic light emitting element" or "organic EL element") is an electronic element including a pair of electrodes and an organic compound layer disposed between the electrodes. By injecting electrons and holes through the pair of electrodes, excitons of the luminescent organic compound in the organic compound layer are generated. When the excitons return to their ground state, the organic light emitting element emits light.

[0003] Recent progress in organic light-emitting elements has been remarkable, and low driving voltage, various emission wavelengths, high-speed responsiveness, and thinner and lighter light-emitting elements have become possible.

[0004] For organic light-emitting elements with higher efficiency, it is known to use materials such as phosphorescent light-emitting materials or delayed fluorescent materials. It is known that any of these materials has a light-emitting mechanism via a triplet excited state and therefore degrades due to the transition energy from the triplet excited state to a higher excited state. Such organic light-emitting elements obtained using materials utilizing triplet states are required to have improved element durability.

[0005] Patent Document 1 describes a ternary fluorescent light-emitting layer comprising two light-emitting materials each having HOMO and LUMO energy levels different from those of the light-emitting layer main body as a configuration for improving device durability. Patent Documents 2 and 3 describe improving device durability by using organic compounds 1-a and 2-a having a nitrogen-containing fused ring skeleton as high-stability materials.

[0006] [Chemical formula 1]

[0007]

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Laid-Open No. 2011-71194

[0011] Patent Document 2: International Publication No. 2012 / 077582

[0012] Patent Document 3: Japanese Patent Laid-Open No. 2012-72099 Summary of the invention

[0013] Problem that the invention aims to solve

[0014] However, the configuration of the light-emitting layer described in Patent Document 1 is a light-emitting layer that emits fluorescence, and does not disclose an organic light-emitting element utilizing a triplet state. The configurations of the light-emitting layers described in Patent Documents 2 and 3 result in insufficient element durability and are not preferred.

[0015] The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide an organic light-emitting element having excellent element durability.

[0016] Solutions for solving problems

[0017] The organic light-emitting element according to the present invention is an organic light-emitting element comprising a first electrode, a second electrode and an organic compound layer disposed between the first electrode and the second electrode. The organic compound layer comprises a light-emitting layer. The light-emitting layer comprises at least a first organic compound, a second organic compound and a phosphorescent light-emitting compound. The lowest excited triplet energy of the first organic compound and the second organic compound is higher than the lowest excited triplet energy of the light-emitting compound. All freely rotatable single bonds in the first organic compound are carbon-carbon bonds. The organic light-emitting element satisfies the relationship of formula (1).

[0018] |HOMO (H2)| > |HOMO (H1)| (1)

[0019] Effects of the Invention

[0020] According to the present invention, an organic light-emitting element having excellent element durability can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] [ Figure 1A ] A schematic cross-sectional view showing an example of a pixel of a display device according to an embodiment of the present invention.

[0022] [ Figure 1B ] A schematic cross-sectional view of an example of a display device including an organic light-emitting element according to an embodiment of the present invention.

[0023] [ Figure 2 ] is a schematic diagram showing an example of a display device according to an embodiment of the present invention.

[0024] [ Figure 3A ] is a schematic diagram showing an example of an image pickup device according to an embodiment of the present invention.

[0025] [ Figure 3B ] is a schematic diagram showing an example of an electronic device according to an embodiment of the present invention.

[0026] [ Figure 4A ] is a schematic diagram showing an example of a display device according to an embodiment of the present invention.

[0027] [ Figure 4B ]A schematic diagram showing an example of a foldable display device.

[0028] [ Figure 5A ] is a schematic diagram showing an example of a lighting device according to an embodiment of the present invention.

[0029] [ Figure 5B ] is a schematic diagram showing an example of an automobile including a vehicle lamp according to an embodiment of the present invention.

[0030] [ Fig. 6A ] shows a schematic diagram of an example of a wearable device according to an embodiment of the present invention.

[0031] [ Figure 6B ] shows a schematic diagram of an example of a wearable device according to an embodiment of the present invention, which includes a camera device.

[0032] [ Fig. 7A ] A schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention.

[0033] [ Figure 7B ] is a schematic diagram showing an example of an exposure light source of an image forming apparatus according to an embodiment of the present invention.

[0034] [ Figure 7C ] is a schematic diagram showing an example of an exposure light source of an image forming apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In the present specification, examples of the halogen atom include fluorine, chlorine, bromine and iodine, but are not limited thereto. Among them, a fluorine atom is preferred.

[0036] The alkyl group may be an alkyl group having 1 to 20 carbon atoms. Examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, sec-butyl, octyl, cyclohexyl, 1-adamantyl, and 2-adamantyl, but are not limited thereto.

[0037] The alkoxy group may be an alkoxy group having 1 to 10 carbon atoms. Examples include methoxy, ethoxy, propoxy, 2-ethyl-octyloxy, and benzyloxy groups, but are not limited thereto.

[0038] Examples of the silyl group include a trimethylsilyl group and a triphenylsilyl group, but are not limited thereto.

[0039] The aryl group may be an aryl group having 6 to 20 carbon atoms, and examples include a phenyl group, a naphthyl group, an indenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a phenanthrenyl group, a fluoranthenyl group, and a triphenylenyl group, but are not limited thereto.

[0040] The heteroaryl group may be a heteroaryl group having 3 to 20 carbon atoms. Examples include pyridyl, pyrimidyl, pyrazolyl, triazolyl, oxazolyl, oxadiazolyl, thiazolyl, thiadiazolyl, carbazolyl, acridinyl, phenanthrolyl, dibenzofuranyl, and dibenzothiophenyl, but are not limited thereto.

[0041] Examples of the amino group include N-methylamino, N-ethylamino, N,N-dimethylamino, N,N-diethylamino, N-methyl-N-ethylamino, N-benzylamino, N-methyl-N-benzylamino, N,N-dibenzylamino, anilino, N,N-diphenylamino, N,N-dinaphthylamino, N,N-difluorenylamino, N-phenyl-N-tolylamino, N,N-ditolylamino, N-methyl-N-phenylamino, N,N-dianisolylamino, N-mesityl-N-phenylamino, N,N-dimesitylamino, N-phenyl-N-(4-tert-butylphenyl)amino, N-phenyl-N-(4-trifluoromethylphenyl)amino, N-piperidinyl and carbazolyl, but are not limited thereto.

[0042] Examples of the aryloxy group and the heteroaryloxy group include a phenoxy group and a thienyloxy group, but are not limited thereto.

[0043] Examples of substituents that the alkyl, alkoxy, silyl, aryl, heteroaryl, amino, aryloxy and heteroaryloxy groups may further have include deuterium atoms; halogen atoms such as fluorine, chlorine, bromine and iodine; alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl and tert-butyl; alkoxy groups such as methoxy, ethoxy and propoxy; amino groups such as dimethylamino, diethylamino, dibenzylamino, diphenylamino and ditolylamino; aryloxy groups such as phenoxy; aromatic hydrocarbon groups such as phenyl and biphenyl; heteroaryl groups such as pyridyl and pyrrolyl; cyano, hydroxyl and thiol groups, but are not limited thereto.

[0044] In this specification, HOMO(H1), HOMO(H2), and HOMO(D) represent the HOMO energy level of the first organic compound, the HOMO energy level of the second organic compound, and the HOMO energy level of the luminescent compound, respectively. LUMO(H1), LUMO(H2), and LUMO(D) represent the LUMO energy level of the first organic compound, the LUMO energy level of the second organic compound, and the LUMO energy level of the luminescent compound, respectively. For example, the expression |HOMO(H1)| refers to the absolute value of the HOMO energy level of the first organic compound.

[0045] (1) Organic light-emitting elements

[0046] The organic light-emitting element according to the present invention is an organic light-emitting element comprising a first electrode, a second electrode and an organic compound layer disposed between the first electrode and the second electrode. The organic compound layer comprises a light-emitting layer. The light-emitting layer comprises at least a first organic compound, a second organic compound and a phosphorescent light-emitting compound. The lowest excited triplet energy of the first organic compound and the second organic compound is higher than the lowest excited triplet energy of the light-emitting compound. All freely rotatable single bonds in the first organic compound are carbon-carbon bonds. The organic light-emitting element satisfies the relationship of formula (1).

[0047] |HOMO (H2)| > |HOMO (H1)| (1)

[0048] The light-emitting layer of the organic light-emitting element according to the present invention has the following configuration.

[0049] (1-1) The light-emitting layer contains at least a first organic compound, a second organic compound and a light-emitting compound. (1-2) The lowest excited triplet energy of the first organic compound and the second organic compound is higher than the lowest excited triplet energy of the light-emitting compound. (1-3) All freely rotatable single bonds in the first organic compound are carbon-carbon bonds. (1-4) The first organic compound and the second organic compound satisfy |HOMO(H2)|>|HOMO(H1)|

[0050] These configurations will be described below.

[0051] (1-1) The light-emitting layer contains at least a first organic compound, a second organic compound and a light-emitting compound

[0052] The organic light emitting element according to the present invention contains at least a first organic compound, a second organic compound and a light emitting compound in the light emitting layer. Here, the effect of the presence of the first organic compound and the second organic compound in the light emitting layer will be described with reference to Table 1.

[0053] The composition of the light emitting layer and the device durability are shown in Table 1. The device durability is a value based on the device durability of Comparative Example B being set to 1.0.

[0054] [Table 1]

[0055] Table 1

[0056]

[0057] In Table 1, Comparative Examples A to C each have an element configuration in which the absolute value of the LUMO energy level of the light-emitting compound is the smallest. Electrons are likely to be captured by a compound having a small absolute value of the LUMO energy level, and therefore in the case of the element configurations of Comparative Examples A to C, electrons are likely to be captured by the light-emitting compound. As will be described in detail later, when the light-emitting compound is likely to capture electrons or holes, exciton generation is likely to be concentrated on the light-emitting compound, and thus element durability is likely to be reduced.

[0058] Although Comparative Example D has an element composition in which the absolute value of the LUMO energy level of the first organic compound is the smallest, the value of element durability is low. When the absolute value of the LUMO energy level of the organic compound is large, the absolute value of the HOMO energy level of the organic compound also tends to be large, and therefore the absolute value of the HOMO energy level of the first organic compound is large. Holes are likely to be captured by compounds with a small absolute value of the HOMO energy level. In the case of the element composition of Comparative Example D, the absolute value of the HOMO energy level of the first organic compound is large, and therefore holes are unlikely to be injected into the light-emitting layer. Therefore, the carrier balance between electrons and holes in the light-emitting layer is disturbed, and as a result, due to the residual carriers in the light-emitting layer, the element durability is reduced.

[0059] In contrast, in the present invention A, the absolute value of the LUMO energy level of the second organic compound is the largest, and therefore the electron is less likely to be captured by the luminescent compound. In addition, the absolute value of the LUMO energy level of the first organic compound is the smallest, and therefore the absolute value of the HOMO energy level of the first organic compound is also low. Therefore, holes are likely to be injected into the light-emitting layer. Therefore, the presence of the first organic compound and the second organic compound in the light-emitting layer can adjust the carrier balance between electrons and holes, thereby resulting in improved element durability.

[0060] (1-2) The lowest excited triplet energy of the first organic compound and the second organic compound is higher than the lowest excited triplet energy of the luminescent compound

[0061] In order to provide an organic light-emitting element with improved luminous efficiency, it is necessary to effectively utilize the lowest excited triplet energy (T1) of the light-emitting compound for luminescence. To achieve this, in the light-emitting layer, the light-emitting compound needs to have the lowest T1. In the organic light-emitting element according to the present invention, the T1 of the first organic compound and the T1 of the second organic compound are higher than the T1 of the light-emitting compound. In other words, the T1 of the light-emitting compound is lower than the T1 of the first organic compound and the second organic compound.

[0062] The composition of the light-emitting layer and the external quantum yield (EQE) are shown in Table 2. Comparative Example a is an organic light-emitting element described in Patent Document 1.

[0063] [Table 2]

[0064] Table 2

[0065]

[0066] In Comparative Example E, the light-emitting compound is a light-emitting compound that emits fluorescence and loses most of T1 due to thermal deactivation, so EQE is low. Comparative Example F is an organic light-emitting element in which the light-emitting compound is a light-emitting compound that emits phosphorescence and T1 of the light-emitting compound is higher than T1 of the first organic compound and the second organic compound. The organic light-emitting element of Comparative Example F does not have a configuration in which T1 of the light-emitting compound is the lowest and therefore cannot effectively utilize T1 of the light-emitting compound. Therefore, EQE is low.

[0067] In contrast, in the present invention B as an embodiment of the present invention, the light-emitting compound is a light-emitting compound that emits phosphorescence, and T1 of the light-emitting compound is lower than T1 of the first organic compound and the second organic compound. Therefore, T1 of the light-emitting compound can be effectively used for light emission, and thus EQE is high. Therefore, the organic light-emitting element according to the present invention is an organic light-emitting element with high light-emitting efficiency because T1 of the light-emitting compound is lower than T1 of the first organic compound and the second organic compound.

[0068] (1-3) All freely rotatable single bonds in the first organic compound are carbon-carbon bonds.

[0069] In this specification, the first organic compound is responsible for most of the exciton generation in the organic light-emitting element. Therefore, the first organic compound is required to have a skeleton that is not easily decomposed even in a high-energy excited state. Here, the skeleton that is not easily decomposed refers to a skeleton including a freely rotatable single bond with high binding energy. In this specification, the term "freely rotatable single bond" refers to a bond represented as "AB", in which unit A and unit B are single-bonded, and unit A and unit B do not form a condensed ring. Units A and B can each be an atom such as a carbon atom or a nitrogen atom or a molecule such as benzene or carbazole. Table 3 shows the binding energy of various bonds.

[0070] [Table 3]

[0071] Table 3

[0072]

[0073] The binding energy of F1 and F2 with carbon-nitrogen bonds is 3.9 eV. The binding energy of F4 with a freely rotatable carbon-carbon bond is 4.5 eV, and the binding energy of F3 with a bond between sp2 carbons that can rotate freely is 5.0 eV. Therefore, when all the freely rotatable single bonds are carbon-carbon bonds, a skeleton that is not easily decomposed is formed, which is preferred. Among carbon-carbon bonds, the bond between sp2 carbons has a particularly high binding energy, and therefore a skeleton in which all the freely rotatable single bonds are bonds between sp2 carbons is more preferred because it is less easily decomposed.

[0074] In the organic light emitting element according to the present invention, the recombination of electrons and holes occurs not only in the first organic compound but also in the second organic compound. Therefore, in addition to the first organic compound, in the second organic compound, all freely rotatable single bonds are preferably carbon-carbon bonds. From the viewpoint of bonding stability, it is more preferred that all freely rotatable single bonds are bonds between sp2 carbons.

[0075] Table 4 compares the element durability of organic light-emitting elements with respect to first organic compounds having different skeletons.

[0076] [Table 4]

[0077] Table 4

[0078]

[0079] Comparative Example G, in which a portion of the freely rotatable single bonds in the first organic compound are carbon-nitrogen bonds with low binding energy, is inferior to the present invention in terms of element durability. In contrast, the present inventions C and D, in which the freely rotatable single bonds in the first organic compound are carbon-carbon bonds with high binding energy, have excellent element durability. In particular, the present invention C, in which the freely rotatable single bonds are bonds between sp2 carbons with higher binding energy, exhibits more excellent element durability. Therefore, the organic light-emitting element according to the present invention is an organic light-emitting element with excellent element durability, because all the freely rotatable single bonds in the first organic compound are carbon-carbon bonds.

[0080] (1-4) The first organic compound and the second organic compound satisfy |HOMO(H2)|>|HOMO(H1)|

[0081] In the organic light emitting element according to the present invention, the first organic compound is mainly responsible for hole transport, and therefore the hole injection property to the first organic compound is required to be higher than that to the second organic compound. Therefore, the organic light emitting element according to the present invention needs to satisfy the relationship of formula (1).

[0082] |HOMO (H2)| > |HOMO (H1)| (1)

[0083] When the absolute value of the HOMO level of the first organic compound is smaller than the absolute value of the HOMO level of the second organic compound, it can be expected that the hole injection property into the first organic compound is improved.

[0084] In the organic light-emitting element according to the present invention, the second organic compound is mainly responsible for electron transport. Examples of skeletons with electron transport properties include azine derivatives and ketone derivatives, but these skeletons have poor stability in the radical cation state and are therefore not suitable for hole transport. Therefore, it is preferred that holes can be effectively injected from the second organic compound to the first organic compound. Also from this viewpoint, it is preferred to satisfy formula (1).

[0085] The organic light emitting element according to the present invention preferably further has the following configuration. Only one of the following configurations may be satisfied, or two or more of the configurations may be satisfied.

[0086] (1-5) satisfies at least one of equations (2) or (3)

[0087] |LUMO (H2)| > |LUMO (D)| (2)

[0088] |HOMO (D)| > |HOMO (H1)| (3)

[0089] (1-6) satisfies equations (2) and (4)

[0090] |LUMO (H2)| > |LUMO (D)| (2)

[0091] |LUMO (H1)| > |LUMO (D)| (4)

[0092] (1-7) satisfies equations (3) to (5)

[0093] |HOMO (D)| > |HOMO (H1)| (3)

[0094] |LUMO (H1)| > |LUMO (D)| (4)

[0095] |LUMO (H1)| > |LUMO (H2)| (5)

[0096] These are described below.

[0097] (1-5) satisfies at least one of equation (2) or equation (3)

[0098] |LUMO (H2)| > |LUMO (D)| (2)

[0099] |HOMO (D)| > |HOMO (H1)| (3)

[0100] In the organic light-emitting element according to the present invention, it is preferred that electrons and holes are less likely to be concentrated on the light-emitting compound. In other words, exciton generation is preferably less likely to be concentrated on the light-emitting compound. This is because the concentration of exciton generation on the light-emitting compound may cause the light-emitting compound to transition to a higher energy state. As a result, the light-emitting compound undergoes bond breakage, so that the concentration of the light-emitting compound in the light-emitting layer decreases, resulting in brightness degradation. Therefore, it is preferred to satisfy at least one of formulas (2) or (3). Satisfying one of them reduces the possibility of electrons and holes being captured on the light-emitting compound at the same time, thereby reducing the possibility of exciton generation concentration. Therefore, the organic light-emitting element has more excellent element durability.

[0101] More preferably, both the formula (2) and the formula (3) are satisfied. Satisfying both the formula (2) and the formula (3) simultaneously reduces the possibility of electrons and holes being concentrated on the light-emitting compound, which is more preferable from the viewpoint of the element durability of the organic light-emitting element.

[0102] Tables 5 to 7 show the composition of the organic light-emitting element according to the present invention and the relative values ​​of the element durability. In Table 5, the element durability of the present invention E is based on the value of setting the element durability of the present invention F to 1.0. In Table 6, the element durability of the present invention G is based on the value of setting the element durability of the present invention H to 1.0. In Table 7, the element durability of the comparative example H is based on the value of setting the element durability of the comparative example I to 1.0.

[0103] [Table 5]

[0104] Table 5

[0105]

[0106] [Table 6]

[0107] Table 6

[0108]

[0109] [Table 7]

[0110] Table 7

[0111]

[0112] In Table 5 and Table 6, the present invention E and G are structures satisfying formula (2) and formula (3). In contrast, the present invention F and H are structures satisfying only formula (2). Although the structure satisfying only formula (2) can provide high element durability, the structure satisfying formula (2) and formula (3) shows more excellent element durability. This is because, as described above, electrons and holes are less likely to concentrate on the luminescent compound, so the degradation of the luminescent compound can be suppressed.

[0113] In addition, referring to the present inventions E and G in Tables 5 and 6, the value of element durability of the present invention E in which all freely rotatable single bonds in the first organic compound are bonds between sp2 carbons is 1.2, which is higher than that of the present invention G. Therefore, the higher the bonding stability of the skeleton of the first organic compound, the greater the effect of the composition (1-4).

[0114] In Table 7, Comparative Example H satisfies Formula (2) and Formula (3), and Comparative Example I satisfies only Formula (2). However, since a carbon-nitrogen bond is included in the first organic compound as a freely rotatable single bond, the bonding stability is low, and improvement in element durability is not confirmed. Therefore, in the case of an organic light-emitting element including an organic compound in which all freely rotatable single bonds are carbon-carbon bonds, the element durability improvement effect of this configuration can be fully produced.

[0115] (1-6) satisfies equations (2) and (4)

[0116] |LUMO (H2)| > |LUMO (D)| (2)

[0117] |LUMO (H1)| > |LUMO (D)| (4)

[0118] In the organic light-emitting element according to the present invention, the absolute value of the LUMO energy level of the light-emitting compound is preferably the lowest. This is because the above-mentioned structure further reduces the possibility of electrons being captured on the light-emitting compound. As a result, the generation of excitons on the light-emitting compound can be suppressed, resulting in further improved element durability.

[0119] Table 8 shows the composition and durability of each organic light-emitting element. Invention I is a composition in which the compound having the smallest absolute value of LUMO energy level is the light-emitting compound. Invention J is a composition in which the compound having the smallest absolute value of LUMO energy level is the first organic compound.

[0120] [Table 8]

[0121] Table 8

[0122]

[0123] Table 8 shows that the device durability of the present invention I is higher than that of the present invention J. This is because, in the composition I of the present invention, the compound having the smallest absolute value of the LUMO level is the light-emitting compound, and thus the generation of excitons in the light-emitting compound can be suppressed.

[0124] (1-7) satisfies equations (3) to (5)

[0125] |HOMO (D)| > |HOMO (H1)| (3)

[0126] |LUMO (H1)| > |LUMO (D)| (4)

[0127] |LUMO (H1)| > |LUMO (H2)| (5)

[0128] In the organic light-emitting element according to the present invention, exciton generation is preferably concentrated on the first organic compound. In other words, it is preferred that the absolute value of the HOMO energy level of the first organic compound is the smallest and the absolute value of the LUMO energy level of the first organic compound is the largest. This is because the above-mentioned structure enables the recombination of electrons and holes to be more effectively performed on the first organic compound. In addition, the consumption rate of excitons can also be improved, and thus the effect of suppressing the deactivation of excitons can also be produced.

[0129] Table 9 shows the composition and element durability of each organic light-emitting element. The present invention K is a composition in which the absolute value of the HOMO energy level of the first organic compound is the smallest and the absolute value of the LUMO energy level of the first organic compound is the largest. The present invention composition L is a composition in which the absolute value of the HOMO energy level of the light-emitting compound is the smallest and the absolute value of the LUMO energy level of the first organic compound is the largest.

[0130] [Table 9]

[0131] Table 9

[0132]

[0133] Table 9 shows that the device durability of the present invention K is higher than that of the present invention L. This is because the present invention K is a configuration in which the absolute value of the HOMO level of the first organic compound is the smallest and the absolute value of the LUMO level of the first organic compound is the largest, and thus exciton generation occurs intensively on the first organic compound.

[0134] (2) First organic compound

[0135] In the organic light emitting element according to the present invention, all the freely rotatable single bonds in the first organic compound are carbon-carbon bonds. Preferably, all the freely rotatable single bonds are composed of bonds between sp2 carbons.

[0136] As described in (1-2), in the light-emitting layer of the organic light-emitting element according to the present invention, the T1 of the first organic compound and the second organic compound is higher than the T1 of the light-emitting compound. The organic compounds have a larger band gap because their lowest excited singlet energy (S1) is higher than their T1. In other words, the difference between the HOMO energy level and the LUMO energy level of the first organic compound and the second organic compound is large. Therefore, electrons or holes are likely to be captured on the light-emitting compound. This causes exciton generation to be concentrated on the light-emitting compound, thereby causing degradation of the light-emitting compound. Therefore, the first organic compound preferably has a hole transport property. Using an organic compound that exhibits hole transport as the first organic compound can suppress the concentration of exciton generation on the light-emitting compound. In this specification, hole transport refers to the ability to move holes. More preferably, the mobility of holes is higher than the mobility of electrons. Specifically, the first organic compound preferably has a skeleton represented by the general formula (1-1) or (1-2).

[0137] [Chemical formula 2]

[0138]

[0139] In the general formulae (1-1) and (1-2), the cyclic units A to C are each independently selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups. Q1 to Q3 are each independently selected from direct bonds, C(R A )(R B )、N(R C ), oxygen atoms, sulfur atoms, selenium atoms and tellurium atoms. A To R C R is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group. C Together with an adjacent one of the cyclic units A to C, a ring is formed.

[0140] Specific skeletons represented by the general formulae (1-1) and (1-2) are shown below, but these are not intended to be limiting.

[0141] [Chemical formula 3]

[0142]

[0143] The general formulas (1-1) and (1-2) may have an aryl or heteroaryl group through a direct bond or a phenyl group. The number of such phenyl groups may be one or more. The phenyl group may be bonded in the meta position or the para position, and preferably in the meta position. The aryl or heteroaryl group bonded through the phenyl group may further have a substituent, and the substituent may be an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. Specifically, the substituent may be a methyl group, a tert-butyl group, a phenyl group or a biphenyl group.

[0144] Specific examples of the first organic compound are shown below. However, the present invention is not limited thereto.

[0145] [Chemical formula 4]

[0146]

[0147] [Chemical formula 5]

[0148]

[0149] [Chemical formula 6]

[0150]

[0151] [Chemical formula 7]

[0152]

[0153] [Chemical formula 8]

[0154]

[0155] (3) Second organic compound

[0156] In the organic light-emitting element according to the present invention, all freely rotatable single bonds in the second organic compound are carbon-carbon bonds. Preferably, all freely rotatable single bonds are composed of bonds between sp2 carbons. In order to further suppress the generation of excitons on the luminescent compound, it is preferred to use an organic compound with electron transport properties as the second organic compound. This is because having this structure can further suppress the generation of excitons on the luminescent compound. In this specification, electron transport properties refer to the ability to move electrons. More preferably, the mobility of electrons is higher than the mobility of holes. Specifically, the first organic compound preferably has a skeleton represented by any of the general formulas (2-1) to (2-7).

[0157] [Chemical formula 9]

[0158]

[0159] In the general formulae (2-1) and (2-2), the cyclic units D to F are each independently selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups. Q4 is each independently selected from direct bonds, C(R D )(R E ), oxygen atoms, sulfur atoms, selenium atoms and tellurium atoms. D and R E Each is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group. n is an integer of 1 to 5.

[0160] In the general formulas (2-3) to (2-7), R1 to R 20 R1 to R2 are each independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, and a substituted or unsubstituted aryl group. 20 In the above-mentioned formula (I), adjacent substituents may be bonded together to form a condensed ring.

[0161] Specific skeletons represented by general formulae (2-1) to (2-7) are shown below, but these are not meant to be restrictive.

[0162] [Chemical formula 10]

[0163]

[0164] General formulas (2-1) to (2-7) may have an aryl or heteroaryl group through a phenyl group or a pyridyl group. The number of such phenyl groups or pyridyl groups may be one or more. The phenyl group or the pyridyl group may be bonded at the meta position or the para position, and preferably bonded at the meta position. The aryl or heteroaryl group bonded through the phenyl group or the pyridyl group may further have a substituent, and the substituent may be an aryl group having 6 to 12 carbon atoms. Specifically, the substituent may be a phenyl group or a biphenyl group.

[0165] Specific examples of the second organic compound are shown below. However, the present invention is not limited thereto.

[0166] [Chemical formula 11]

[0167]

[0168] [Chemical formula 12]

[0169]

[0170] [Chemical formula 13]

[0171]

[0172] (4) Luminescent compounds

[0173] The light-emitting compound may be any compound that mainly emits phosphorescence, and is preferably an organic metal complex represented by the general formula (3).

[0174] M(L)m(L')n(L“)p(3)

[0175] In the general formula (3), M represents a metal atom. Specifically, M is an iridium atom or a platinum atom, preferably an iridium atom. L, L' and L" represent bidentate ligands that are different from each other. m is selected from integers from 1 to 3, and n and p are selected from integers from 0 to 2, with the condition that m+n+p=3. When m is 2 or more, L may be the same or different. When n is 2 or more, L' may be the same or different. When p is 2 or more, L" may be the same or different.

[0176] M(L)m is represented by the general formula (4-1).

[0177] [Chemical formula 14]

[0178]

[0179] In the general formula (4-1), Z1 to Z4 are each independently selected from C(R 21 ) and nitrogen atoms. 21 To R 28 R is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group and a cyano group. 21 To R 28 At least one of them is selected from substituted or unsubstituted aryl and substituted or unsubstituted heteroaryl. When Z1 to Z4 are C(R 21 ) indicates that R 21 May be the same as or different from each other.

[0180] R 21 To R 28 Adjacent two of them may be bonded to each other to form a ring.

[0181] M(L')n is represented by the general formula (4-2).

[0182] [Chemical formula 15]

[0183]

[0184] In formula (4-2), Z5 to Z8 are each independently selected from C(R 35 ) and nitrogen atoms. 31 To R 35Each is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group and a cyano group. 35 ) indicates that R 35 May be the same as or different from each other.

[0185] R 31 To R 35 Adjacent two of them may be bonded to each other to form a ring.

[0186] M(L")p is represented by the general formula (4-3).

[0187] [Chemical formula 16]

[0188]

[0189] In formula (4-3), R 39 To R 41 Each is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group and a cyano group.

[0190] Non-limiting specific examples of the partial structure M(L)m of the organometallic complex as the light-emitting compound are shown below. In the following specific examples, the coordination bond is represented by a straight line, a dotted line or an arrow.

[0191] [Chemical formula 17]

[0192]

[0193] [Chemical formula 18]

[0194]

[0195] [Chemical formula 19]

[0196]

[0197] In the general formulae [Ir-5] to [Ir-8], [Ir-15] and [Ir-16], X' is selected from an oxygen atom, a sulfur atom, a substituted or unsubstituted carbon atom and a substituted or unsubstituted nitrogen atom.

[0198] In the general formulas [Ir-1] to [Ir-20], R 21 To R 29Adjacent two of them may be bonded to each other to form a ring.

[0199] In the luminescent compound according to the present invention, the partial structure M(L)m preferably has a condensed ring consisting of three or more rings. This is because the presence of the condensed ring consisting of three or more rings improves the planarity of the molecule to promote energy transfer from the first organic compound or the second organic compound to the phosphorescent light-emitting material, resulting in improvements in luminous efficiency and element durability. Examples of condensed rings consisting of three or more rings include those in the general formulas [Ir-3] to [Ir-8] and [Ir-11] to [Ir-16]. Specific examples include phenanthrene rings, triphenylene rings, benzofluorene rings, dibenzofuran rings, dibenzothiophene rings, benzonaphthofuran rings, benzonaphthothiophene rings, benzoisoquinoline rings, and naphthoisoquinoline rings.

[0200] Specific examples of the light-emitting compound are shown below. However, the present invention is not limited thereto.

[0201] [Chemical formula 20]

[0202]

[0203] [Chemical formula 21]

[0204]

[0205] [Chemical formula 22]

[0206]

[0207] [Chemical formula 23]

[0208]

[0209] [Chemical formula 24]

[0210]

[0211] [Chemical formula 25]

[0212]

[0213] [Chemical formula 26]

[0214]

[0215] [Chemical formula 27]

[0216]

[0217] [Chemical formula 28]

[0218]

[0219] [Chemical formula 29]

[0220]

[0221] [Chemical formula 30]

[0222]

[0223] [Chemical formula 31]

[0224]

[0225] [Chemical formula 32]

[0226]

[0227] [Chemical formula 33]

[0228]

[0229] [Chemical formula 34]

[0230]

[0231] [Chemical formula 35]

[0232]

[0233] Exemplary compounds belonging to the AA group and the BB group are metal complexes whose partial structure M(L)m is represented by the general formula [Ir-3] and are compounds having a phenanthrene ring in a ligand. These compounds are compounds having particularly high stability.

[0234] Exemplary compounds belonging to the CC group are metal complexes whose partial structure M(L)m is represented by the general formula [Ir-4] and are compounds having a triphenylene ring in the ligand. These compounds are compounds having particularly high stability.

[0235] Exemplary compounds belonging to the DD group are metal complexes whose partial structure M(L)m is represented by any of the general formulas [Ir-5] to [Ir-8], and are compounds having a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, or a benzonaphthothiophene ring in the ligand. These compounds contain oxygen atoms or sulfur atoms, and the abundant non-shared electron pairs of these atoms can enhance charge transportability. Therefore, these are compounds that are particularly helpful in adjusting carrier balance.

[0236] Exemplary compounds belonging to the EE group to the GG group are metal complexes whose partial structure M(L)m is represented by any of the general formulas [Ir-6] to [Ir-8], and are compounds having a benzofluorene ring in the ligand. These compounds have a substituent in the 9-position of the fluorene ring in a direction perpendicular to the in-plane direction of the fluorene ring, and are therefore particularly capable of suppressing the overlapping of condensed rings. Therefore, these are compounds having particularly high sublimability.

[0237] Exemplary compounds belonging to the HH group are metal complexes whose partial structure M(L)m is represented by any of the general formulas [Ir-11] to [Ir-13], and are compounds having a benzoisoquinoline ring in the ligand. These compounds contain a nitrogen atom in a condensed ring, and the non-shared electron pair and high electronegativity of the atom can enhance charge transportability. Therefore, these are compounds that are particularly helpful in adjusting carrier balance.

[0238] Exemplary compounds belonging to Group II are metal complexes whose partial structure M(L)m is represented by the general formula [Ir-14] and are compounds having a naphthoisoquinoline ring in the ligand. These compounds contain a nitrogen atom in a condensed ring, and the non-shared electron pair and high electronegativity of the atom can enhance charge transportability. Therefore, these are compounds that are particularly helpful in adjusting carrier balance.

[0239] <<Organic Light Emitting Device>>

[0240] The organic light emitting element according to the embodiment includes a first electrode and a second electrode and an organic compound layer disposed between the first electrode and the second electrode. The organic compound layer includes at least a light emitting layer. The organic compound layer may be a single layer or a stack of multiple layers. When the organic compound layer is a stack of multiple layers, at least one layer is a light emitting layer. In addition to the light emitting layer, the organic compound layer may also include a hole injection layer, a hole transport layer, an electron blocking layer, a hole / exciton blocking layer, an electron transport layer, and an electron injection layer. These layers contain at least one organic compound, and the T1 of the organic compound is preferably different from the T1 of the first organic compound and the T1 of the second organic compound and is higher than the T1 of the first organic compound and the T1 of the second organic compound. The light emitting layer may be a single layer or a stack of multiple layers.

[0241] In the organic light emitting element according to this embodiment, at least one organic compound layer contains the organic compound according to this embodiment.

[0242] The first organic compound or the second organic compound is also referred to as a host or a host material, and is a compound that has the largest mass ratio among the compounds constituting the light-emitting layer. The luminescent compound is also referred to as a guest, a guest material or a luminescent material, and is a compound that has a smaller mass ratio than the host among the compounds constituting the light-emitting layer and is mainly responsible for luminescence.

[0243] The host of the light-emitting layer according to this embodiment includes at least two hosts. The concentration of these hosts is preferably 10 mass % or more and 90 mass % or less, more preferably 20 mass % or more and 80 mass % or less, and even more preferably 30 mass % or more and 70 mass % or less relative to the total mass of the light-emitting layer.

[0244] The concentration of the guest relative to the host is 0.01 mass % to 50 mass %, preferably 0.1 mass % to 20 mass %, based on the total amount of the constituent materials of the light emitting layer. From the viewpoint of suppressing concentration quenching, the guest concentration is particularly preferably 10 mass % or less.

[0245] The guest may be contained uniformly or with a concentration gradient throughout the layer in which the host serves as a matrix. Alternatively, the guest may be contained locally in a specific region within the layer so that the light-emitting layer has a region containing only the host and not the guest.

[0246] The light-emitting layer in the present invention may be a single layer or a multilayer, and may also contain light-emitting materials with different luminescent colors to mix colors. The term "multilayer" refers to a state in which a light-emitting layer and another light-emitting layer are stacked on top of each other. In this case, the luminescent color of the organic light-emitting element is not particularly limited. More specifically, the luminescent color may be white or an intermediate color. In the case of white, for example, when the luminescent color of the light-emitting layer is blue, the other light-emitting layer emits light of a color different from blue, i.e., green or red. In addition, a third light-emitting layer and a charge generation layer emitting blue light may be configured between the light-emitting layer or the light-emitting layer stack of the present invention and the first electrode or the second electrode. The charge generation layer activates the function as a tandem element; the electrons generated from the charge generation layer and the holes injected from the first electrode are charge-recombined to generate excitons, and the holes generated from the charge generation layer and the electrons injected from the second electrode are charge-recombined to form excitons. Therefore, the internal quantum efficiency is doubled. In this case, the organic light-emitting element according to the present invention can be applied as a yellow light-emitting layer on one side of the tandem element as a complementary color to blue light emission. Therefore, by using the light-emitting layer stack composed of the light-emitting layer of the present invention and forming a tandem element structure together with the blue light-emitting layer, a white light-emitting element can be provided. The third light-emitting layer contains at least a third organic compound and a fourth organic compound. The third organic compound is a host material, and the fourth organic compound is a blue light-emitting material.

[0247] The layer formation is performed by vapor deposition or coating.

[0248] Specific examples of the element configuration of the organic light-emitting element according to this embodiment include a multilayer element configuration in which the electrode layers and organic compound layers shown in the following (1) to (6) are sequentially stacked on a substrate. In each element configuration, the organic compound layer must include a light-emitting layer containing a light-emitting material without exception.

[0249] (1) Anode / light-emitting layer / cathode

[0250] (2) Anode / hole transport layer / light-emitting layer / electron transport layer / cathode

[0251] (3) Anode / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode

[0252] (4) Anode / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / cathode

[0253] (5) Anode / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode

[0254] (6) Anode / hole transport layer / electron blocking layer / light-emitting layer / hole blocking layer / electron transport layer / cathode

[0255] It should be noted that these exemplary element configurations are merely basic element configurations and are not meant to be restrictive. For example, various layer configurations may be employed, such as a configuration in which an insulating layer, an adhesive layer, or an interference layer is disposed at the interface between an electrode and an organic compound layer, a configuration in which an electron transport layer or a hole transport layer is composed of two layers having different ionization potentials, and a configuration in which a light-emitting layer is composed of two layers formed of different light-emitting materials.

[0256] Among the element configurations shown in (1) to (6) above, configuration (6) is preferred because it is a configuration including both an electron blocking layer and a hole blocking layer. That is, (6) including an electron blocking layer and a hole blocking layer can reliably capture carriers, i.e., holes and electrons, within the light-emitting layer, and thus provide an organic light-emitting element that does not experience carrier leakage and has high light-emitting efficiency.

[0257] Here, the organic light-emitting element according to the present invention is characterized in that all freely rotatable single bonds in the first organic compound and the second organic compound constituting the light-emitting layer are carbon-carbon bonds, preferably bonds between sp2 carbons. This means that it is formed by a host material with high planarity. Therefore, the hole transport capacity and electron transport capacity of the organic light-emitting element are better than those of standard organic light-emitting elements. Therefore, the electron blocking layer and the hole blocking layer play an important role. For example, the hole blocking layer needs to be stable to holes, and therefore the hole blocking layer compound is preferably an organic compound with low reactivity, and further preferably an organic compound consisting only of hydrocarbons. For example, the electron blocking layer also needs to be stable to electrons, and therefore the electron blocking layer compound is preferably an organic compound with low reactivity, and further preferably an organic compound in which all freely rotatable single bonds are carbon-carbon bonds, preferably bonds between sp2 carbons.

[0258] The extraction mode (element configuration) of light output from the light-emitting layer may be a so-called bottom emission mode in which light is extracted from the substrate side electrode or a so-called top emission mode in which light is extracted from the opposite side of the substrate. Alternatively, a double-sided extraction mode in which light is extracted from the substrate side and the opposite side of the substrate may be adopted.

[0259] <Other compounds>

[0260] The organic compound according to the embodiment can be used as a constituent material of an organic compound layer other than the light-emitting layer of the organic light-emitting element according to the embodiment. Specifically, the organic compound can be used as a constituent material of, for example, an electron transport layer, an electron injection layer, a hole transport layer, a hole injection layer, or a hole blocking layer. In this case, the luminescent color of the organic light-emitting element is not particularly limited. More specifically, the luminescent color may be white or an intermediate color.

[0261] In the organic light-emitting element according to this embodiment, known low molecular weight and high molecular weight hole injection compounds or hole transport compounds, compounds serving as hosts, light-emitting compounds, electron injection compounds or electron transport compounds, etc. can be used in combination as needed. Examples of these compounds are as follows.

[0262] As hole injection and transport material, it is preferred to promote the injection of holes from the anode and have such a high hole mobility that the injected holes can be transported to the light-emitting layer. In order to suppress the degradation of film quality such as crystallization in the organic light-emitting element, a material with a high glass transition temperature is preferred. Examples of low molecular weight and high molecular weight materials capable of injecting and transporting holes include triarylamine derivatives, aryl carbazole derivatives, phenylenediamine derivatives, stilbene derivatives, phthalocyanine derivatives, porphyrin derivatives, poly (vinyl carbazole), poly (thiophene) and other conductive polymers. In addition, these hole injection and transport materials are also suitable for electron blocking layers. Non-limiting specific examples of compounds that can be used as hole injection and transport materials are shown below.

[0263] [Chemical formula 36]

[0264]

[0265] Examples of luminescent materials mainly related to luminescent functions include, in addition to the organic metal complex involved in the luminescent layer compound of the present invention, condensed ring compounds (e.g., fluorene derivatives, naphthalene derivatives, pyrene derivatives, perylene derivatives, tetracene derivatives, anthracene derivatives and rubrene), quinacridone derivatives, coumarin derivatives, stilbene derivatives, organic aluminum complexes such as tris(8-quinoline)aluminum, iridium complexes, platinum complexes, rhenium complexes, copper complexes, europium complexes, ruthenium complexes and polymer derivatives such as poly(phenylenevinylene) derivatives, poly(fluorene) derivatives, poly(phenylene) derivatives, etc. Non-limiting specific examples of compounds that can be used as luminescent materials are shown below.

[0266] [Chemical formula 37]

[0267]

[0268] [Chemical formula 38]

[0269]

[0270] As the luminescent layer host or luminescent auxiliary material included in the luminescent layer, a compound other than the organic compound according to the embodiment may be included as a third component. Examples of the third component include aromatic hydrocarbon compounds and derivatives thereof, carbazole derivatives, azine derivatives, xanthone derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, organic aluminum complexes such as tris (8-quinoline) aluminum, and organic beryllium complexes.

[0271] [Chemical formula 39]

[0272]

[0273] Any electron transport material capable of transporting electrons injected from the cathode to the light-emitting layer may be freely selected in consideration of, for example, a balance with the hole mobility of the hole transport material. Examples of materials capable of transporting electrons include oxadiazole derivatives, oxazole derivatives, pyrazine derivatives, triazole derivatives, triazine derivatives, quinoline derivatives, quinoxaline derivatives, phenanthroline derivatives, organoaluminum complexes, and condensed ring compounds (e.g., fluorene derivatives, naphthalene derivatives, (chrysene) derivatives and anthracene derivatives). These electron transporting materials are also suitable for the hole blocking layer. Non-limiting specific examples of compounds that can be used as electron transporting materials are shown below.

[0274] [Chemical formula 40]

[0275]

[0276] Any electron injecting material that can easily inject electrons from the cathode can be freely selected, taking into account, for example, the balance with hole injectability. N-type dopants and reductive dopants are also included as organic compounds. Examples include alkali metal compounds such as lithium fluoride, lithium complexes such as lithium quinolate, benzimidazolidine derivatives, imidazolidine derivatives, fulvalene derivatives, and acridine derivatives. These can also be used in combination with the above-mentioned electron transport materials.

[0277] <Structure of organic light-emitting element>

[0278] An organic light emitting element is provided by forming an insulating layer, a first electrode, an organic compound layer, and a second electrode on a substrate. On the second electrode, a protective layer, a color filter, a microlens, etc. may be configured. When a color filter is configured, a planarization layer may be configured between the color filter and the protective layer. The planarization layer may be formed of, for example, an acrylic resin. This also applies to a case where the planarization layer is configured between the color filter and the microlens.

[0279] [Substrate]

[0280] Examples of substrates include quartz, glass, silicon wafers, resins, and metals. The substrate may have switching elements such as transistors, and wiring, etc., disposed thereon, and may have an insulating layer disposed thereon. The insulating layer may be made of any material as long as a contact hole can be formed therein to allow the wiring connected to the first electrode to be formed and insulation from unconnected wiring can be provided. For example, resins such as polyimide, silicon oxide, and silicon nitride may be used.

[0281] [electrode]

[0282] The electrode may be a pair of electrodes. The pair of electrodes may be an anode and a cathode. When an electric field is applied in the direction in which the organic light-emitting element emits light, one electrode at a higher potential is the anode, and the other is the cathode. In other words, one electrode that supplies holes to the light-emitting layer is the anode, and the other electrode that supplies electrons to the light-emitting layer is the cathode.

[0283] The material constituting the anode preferably has a work function as high as possible. For example, elemental metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium and tungsten, mixtures containing these metals, alloys obtained by combining these metals, and metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO) and indium zinc oxide can be used. Conductive polymers such as polyaniline, polypyrrole, polythiophene, etc. can also be used.

[0284] These electrode materials can be used alone or in combination of two or more. The anode can be composed of a single layer or multiple layers.

[0285] When the anode is used as a reflective electrode, for example, chromium, aluminum, silver, titanium, tungsten, molybdenum, their alloys or their laminates can be used. These materials can also be used as a reflective film without an electrode function. When the anode is used as a transparent electrode, it can be, for example, but not necessarily, a transparent conductive layer made of an oxide such as indium tin oxide (ITO) or indium zinc oxide. The electrode can be formed by photolithography.

[0286] The constituent material of the cathode preferably has a low work function. Examples of such materials include alkali metals such as lithium; alkaline earth metals such as calcium; single metals such as aluminum, titanium, manganese, silver, lead and chromium; and mixtures thereof. Alloys obtained by combining these single metals can also be used. For example, magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper and zinc-silver alloys can be used. Metal oxides such as indium tin oxide (ITO) can also be used. These electrode materials can be used alone or in combination of two or more. The cathode can be composed of a single layer or multiple layers. In particular, silver is preferably used, and silver alloys are more preferably used to reduce the agglomeration of silver. As long as the agglomeration of silver can be reduced, the ratio of the alloy is not limited. For example, the ratio of silver to other metals can be, for example, 1:1 or 3:1.

[0287] The cathode is not particularly limited; a top-emitting element may be provided using a conductive layer formed of an oxide such as ITO, or a bottom-emitting element may be provided using a reflective electrode formed of aluminum (Al), etc. The method of forming the cathode is not particularly limited, and it is more preferable to use DC sputtering or AC sputtering because good film coverage can be achieved and resistance tends to be reduced.

[0288] [Organic compound layer]

[0289] The organic compound layer may be formed of a single layer or multiple layers. When the organic compound layer includes multiple layers, these layers may be referred to as hole injection layers, hole transport layers, electron blocking layers, light-emitting layers, hole blocking layers, electron transport layers, and electron injection layers, according to their functions. The organic compound layer is mainly composed of organic compounds and may contain inorganic atoms and inorganic compounds. For example, the organic compound layer may contain copper, lithium, magnesium, aluminum, iridium, platinum, molybdenum, or zinc. The organic compound layer may be arranged between the first electrode and the second electrode and may be arranged in contact with the first electrode and the second electrode.

[0290] The organic compound layers (eg, hole injection layer, hole transport layer, electron blocking layer, light emitting layer, hole blocking layer, electron transport layer and electron injection layer) constituting the organic light emitting element according to an embodiment of the present invention are formed by the following method.

[0291] The organic compound layer constituting the organic light-emitting element according to the embodiment of the present invention can be formed using a dry method such as vacuum evaporation, ion evaporation, sputtering or plasma. Instead of the dry method, a wet method involving dissolving the material in a suitable solvent and forming a layer by a known coating method (e.g., spin coating, dipping, casting, LB method or inkjet method) can also be used.

[0292] When the layers are formed by, for example, vacuum evaporation or solution coating, the layers are less susceptible to crystallization and are highly stable over time. When a coating method is used to form a film, an appropriate binder resin may be used in combination to form the film.

[0293] Examples of the binder resin include polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin, but are not limited thereto.

[0294] These binder resins may be used alone as a homopolymer or a copolymer or may be used as a mixture of two or more. In addition, known additives such as a plasticizer, an antioxidant, and a UV absorber may be used in combination as needed.

[0295] [Protective layer]

[0296] The protective layer can be configured on the second electrode. For example, a glass member provided with a hygroscopic agent can be bonded to the second electrode to reduce, for example, water intrusion into the organic compound layer, thereby reducing the occurrence of poor display. In another embodiment, a passivation film made of silicon nitride or the like can be configured on the second electrode to reduce, for example, water intrusion into the organic compound layer. For example, after the formation of the second electrode, the resultant can be transferred to another chamber without destroying the vacuum, and a protective layer can be formed by forming a silicon nitride film with a thickness of 2 μm by CVD. After the film is formed by CVD, atomic layer deposition (ALD) can be performed to form a protective layer. The material of the film formed by ALD is not limited and can be, for example, silicon nitride, silicon oxide or aluminum oxide. On the film formed by ALD, silicon nitride can be further formed by CVD. The film formed by ALD can have a smaller thickness than the film formed by CVD. Specifically, the thickness can be less than 50%, or even less than 10%.

[0297] [Color Filter]

[0298] The color filter may be disposed on the protective layer. For example, the color filter may be formed on another substrate to correspond to the size of the organic light emitting element and bonded to the substrate on which the organic light emitting element is disposed. Alternatively, the color filter may be patterned on the protective layer by photolithography. The color filter may be made of a polymer.

[0299] [Planarization layer]

[0300] The planarization layer may be disposed between the color filter and the protective layer. The planarization layer is configured to reduce the unevenness of the lower layer. The planarization layer may be referred to as a material resin layer without limiting the purpose. The planarization layer may be formed of an organic compound. The organic compound may have a low molecular weight or a high molecular weight, and preferably has a high molecular weight.

[0301] The planarization layer may be disposed on the opposite surface of the color filter and its constituent materials may be the same or different. Specific examples include polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenolic resin, epoxy resin, silicone resin and urea resin.

[0302] [Microlens]

[0303] The organic light emitting element or the organic light emitting device may include an optical component such as a microlens on its light emitting side. The microlens may be formed of, for example, an acrylic resin or an epoxy resin. The microlens may be used to increase the amount of light extracted from the organic light emitting element or the organic light emitting device and to control the direction of the extracted light. The microlens may have a hemispherical shape. In the case of a hemispherical shape, among the tangents to the hemisphere, there is a tangent parallel to the insulating layer, and the junction of the tangent and the hemisphere is the vertex of the microlens. The vertex of the microlens can be determined in the same way in any cross-sectional view. That is, among the tangents to the semicircle of the microlens in the cross-sectional view, there is a tangent parallel to the insulating layer, and the junction of the tangent and the semicircle is the vertex of the microlens.

[0304] The midpoint of the microlens may also be defined. In the cross section of the microlens, imagine a line segment from one end point of the arc to the other end point, and the midpoint of the line segment may be referred to as the midpoint of the microlens. The cross section used to determine the vertex and the midpoint may be a cross section perpendicular to the insulating layer.

[0305] [Counter substrate]

[0306] The counter substrate may be arranged on the planarization layer. The counter substrate is arranged at a position opposite to the above-mentioned substrate and is therefore referred to as the counter substrate. The constituent material of the counter substrate may be the same as the constituent material of the above-mentioned substrate. When the above-mentioned substrate is the first substrate, the counter substrate may be the second substrate.

[0307] [Pixel circuit]

[0308] An organic light-emitting device including an organic light-emitting element may include a pixel circuit connected to the organic light-emitting element. The pixel circuit may be an active matrix circuit that independently controls the light emission of a first light-emitting element and a second light-emitting element. The active matrix circuit may be voltage-programmed or current-programmed. The drive circuit includes a pixel circuit for each pixel. The pixel circuit may include a light-emitting element, a transistor that controls the light emission brightness of the light-emitting element, a transistor that controls the light emission timing, a capacitor that maintains the gate voltage of the transistor that controls the light emission brightness, and a transistor that does not provide a connection to GND through the light-emitting element.

[0309] The light emitting device has a display area and a peripheral area configured around the display area. The display area includes a pixel circuit, and the peripheral area includes a display control circuit. The mobility of the transistor constituting the pixel circuit may be lower than the mobility of the transistor constituting the display control circuit. The gradient of the current-voltage characteristic of the transistor constituting the pixel circuit may be less than the gradient of the current-voltage characteristic of the transistor constituting the display control circuit. The gradient of the current-voltage characteristic may be determined based on the so-called Vg-Ig characteristic. The transistor constituting the pixel circuit is a transistor connected to a light emitting element such as a first light emitting element.

[0310] [Pixels]

[0311] An organic light-emitting device including an organic light-emitting element may include a plurality of pixels. Each pixel includes sub-pixels that emit light of different colors from each other. The sub-pixels may have emission colors such as R, G, and B, etc.

[0312] In the pixel, an area also referred to as a pixel opening emits light. This area is the same as the first area. The size of the pixel opening may be less than 15 μm and more than 5 μm. More specifically, the size may be, for example, 11 μm, 9.5 μm, 7.4 μm, or 6.4 μm. The distance between sub-pixels may be less than 10 μm, specifically, 8 μm, 7.4 μm, or 6.4 μm.

[0313] When viewed in a plane, the pixels may be in a known arrangement. For example, the arrangement may be a stripe arrangement, a delta arrangement, a PenTile arrangement, or a Bayer arrangement. The shape of the sub-pixels in a plan view may be any known shape. Examples include quadrilaterals such as rectangles and rhombuses, and hexagons. It should be understood that shapes that are not completely rectangular but are similar to rectangles are also considered rectangles. The shapes of sub-pixels and pixel arrangements may be used in combination.

[0314] <Applications of organic light-emitting devices>

[0315] The organic light emitting element according to this embodiment can be used as a component of a display device or a lighting device. Other uses include an exposure light source in an electrophotographic image forming device, a backlight in a liquid crystal display device, and a light emitting device including a white light source with a color filter.

[0316] The display device may be an image information processor including an image input portion to which image information from an area array CCD, a linear array CCD, or a memory card, etc. is input, including an information processing portion configured to process the input information, and display the input image on a display portion. The display device may include a plurality of pixels such that at least one of the plurality of pixels includes an organic light emitting element according to the embodiment and a transistor connected to the organic light emitting element.

[0317] The display unit of the camera device or inkjet printer may have a touch panel function. The touch panel function may be activated by any method, such as infrared method, electrostatic capacitance method, resistance film method, or electromagnetic induction method. The display device may also be used as a display unit of a multifunction printer.

[0318] Next, a display device according to this embodiment is described with reference to the drawings. Figure 1A and Figure 1B1 and 2 are schematic cross-sectional views showing examples of a display device including an organic light emitting element and a transistor connected to the organic light emitting element. The transistor is an example of an active element. The transistor may be a thin film transistor (TFT).

[0319] Figure 1A is an example of a pixel as a constituent element of the display device according to the embodiment. The pixel includes a sub-pixel 10. The sub-pixels are divided into 10R, 10G, and 10B according to their light emission. The luminous color can be distinguished based on the wavelength of the light emitted from the light-emitting layer, or the light emitted from the sub-pixel can undergo selective transmission or color conversion through a color filter or the like. Each sub-pixel 10 includes a reflective electrode as a first electrode 2, an insulating layer 3 covering the edge of the first electrode 2, an organic compound layer 4 covering the first electrode 2 and the insulating layer 3, a transparent electrode as a second electrode 5, a protective layer 6, and a color filter 7 on an interlayer insulating layer 1.

[0320] The interlayer insulating layer 1 may include a transistor and a capacitor element under or inside the interlayer insulating layer 1. The transistor and the first electrode 2 may be electrically connected to each other through a contact hole (not shown) or the like.

[0321] The insulating layer 3 is also called a bank or a pixel separation film. The insulating layer 3 is arranged to cover the edge of the first electrode 2 and surround the first electrode 2. The portion where the insulating layer 3 is not arranged is in contact with the organic compound layer 4 and serves as a light emitting region.

[0322] The organic compound layer 4 includes a hole injection layer 41 , a hole transport layer 42 , a first light emitting layer 43 , a second light emitting layer 44 , and an electron transport layer 45 .

[0323] The second electrode 5 may be a transparent electrode, a reflective electrode or a semi-transparent electrode.

[0324] The protective layer 6 reduces the penetration of water into the organic compound layer 4. Although the protective layer 6 is shown as a single layer, it may be composed of a plurality of layers. These layers may be composed of an inorganic compound layer and an organic compound layer.

[0325] The color filters 7 are divided into 7R, 7G, and 7B according to their colors. The color filters 7 may be formed on a planarization film (not shown). A resin protective layer (not shown) may be arranged on the color filter 7. The color filter 7 may be formed on the protective layer 6. The color filter may be bonded after being formed on a counter substrate such as a glass substrate.

[0326] Figure 1BThe display device 100 in the embodiment includes an organic light emitting element 26 and a TFT 18 which is an example of a transistor. The display device 100 includes a substrate 11 made of glass or silicon or the like and an insulating layer 12 arranged thereon. An active element such as the TFT 18 is arranged on the insulating layer 12, and a gate electrode 13, a gate insulating film 14 and a semiconductor layer 15 of the active element are arranged. The TFT 18 further includes a drain electrode 16 and a source electrode 17. An insulating film 19 is arranged on the TFT 18. An anode 21 and a source electrode 17 constituting the organic light emitting element 26 are connected to each other through a contact hole 20 extending through the insulating film 19.

[0327] The electrodes (anode 21 and cathode 23) included in the organic light emitting element 26 and the electrodes (source electrode 17 and drain electrode 16) included in the TFT 18 do not necessarily have to be connected in the same manner. Figure 2 (b) The anode 21 or the cathode 23 only needs to be electrically connected to one of the source electrode 17 or the drain electrode 16 of the TFT 18. TFT stands for Thin Film Transistor.

[0328] Although in Figure 1B In the display device 100 of FIG. 1 , the organic compound layer 22 is shown as a single layer, but the organic compound layer 22 may be composed of multiple layers. A first protective layer 24 and a second protective layer 25 for reducing degradation of the organic light emitting element 26 are disposed on the cathode 23 .

[0329] Although in Figure 1B The display device 100 uses transistors as switching elements, but other switching elements may be used instead.

[0330] Figure 1B The transistor used in the display device 100 may be not only a transistor obtained using a single crystal silicon wafer, but also a thin film transistor including a substrate and an active layer on an insulating surface of the substrate. The active layer may be made of, for example, single crystal silicon, non-single crystal silicon such as amorphous silicon or microcrystalline silicon, or non-single crystal oxide semiconductors such as indium zinc oxide or indium gallium zinc oxide. A thin film transistor is also called a TFT element.

[0331] Figure 1B The transistor included in the display device 100 in the embodiment may be formed in a substrate such as a Si substrate, etc. The phrase "formed in a substrate" means that the transistor is produced by processing the substrate itself, such as a Si substrate, etc. That is, having a transistor in a substrate may also mean that the substrate and the transistor are formed integrally.

[0332] The luminous brightness of the organic light-emitting element according to this embodiment is controlled by a TFT as an example of a switching element, and configuring a plurality of organic light-emitting elements in a screen can display images with different luminous brightness. The switching element according to this embodiment does not have to be a TFT and may be a transistor formed of low-temperature polycrystalline silicon or an active matrix driver formed on a substrate such as a Si substrate. The phrase "on a substrate" may also be referred to as "in a substrate". Whether to set a transistor in a substrate or to use a TFT is selected according to the size of the display portion. For example, when the display portion has a size of about 0.5 inches, the organic light-emitting element is preferably configured on a Si substrate.

[0333] Figure 2 1 is a schematic diagram showing an example of a display device according to the embodiment. The display device 1000 may include an upper cover 1001, a lower cover 1009, and a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 configured between the covers. Flexible printed circuits (FPCs) 1002 and 1004 are connected to the touch panel 1003 and the display panel 1005, respectively. Transistors are printed on the circuit board 1007. If the display device is not a mobile device, the battery 1008 can be omitted. If the display device is a mobile device, the battery 1008 can be configured in another position.

[0334] The display device according to the embodiment may include red, green and blue color filters. The red, green and blue color filters may be arranged in a delta arrangement.

[0335] The display device according to this embodiment can be used as a display unit of a mobile terminal. In this case, the display device can have a display function and an operation function at the same time. Examples of mobile terminals include cellular phones such as smart phones, tablet computers, and head-mounted displays.

[0336] The display device according to this embodiment can be used as a display unit of an image pickup device, which includes an optical unit having a plurality of lenses and an image pickup element configured to receive light that has passed through the optical unit. The image pickup device may include a display unit configured to display information obtained by the image pickup element. The display unit may be exposed to the outside of the image pickup device or configured in a viewfinder. The image pickup device may be a digital camera or a digital video camera.

[0337] Figure 3A11 is a schematic diagram showing an example of an imaging device according to the embodiment. The imaging device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The viewfinder 1101 may include a display device according to the embodiment. In this case, the display device may display not only an image to be captured but also environmental information, imaging instructions, and the like. The environmental information may be, for example, the intensity of external light, the direction of external light, the moving speed of a subject, and the possibility that a subject is shielded by an obstruction.

[0338] Since the timing suitable for video recording is only a moment, it is desirable to display information as quickly as possible. Therefore, a display device including an organic light emitting element according to this embodiment is preferably used. This is because the organic light emitting element has a high response speed. A display device including an organic light emitting element is more suitable for such a device that requires fast display than a liquid crystal display device.

[0339] The camera device 1100 includes an optical unit (not shown). The optical unit includes a plurality of lenses and focuses the image onto an image pickup element housed in a housing 1104. By adjusting the relative positions of the plurality of lenses, the focus can be adjusted. This operation can also be performed automatically. The camera device may be referred to as a photoelectric conversion device. Instead of sequential imaging, the photoelectric conversion device may involve detecting differences from previous images, extracting from continuously recorded images, etc. as an imaging method.

[0340] Figure 3B 1201, an operating unit 1202 and a housing 1203. The housing 1203 may include a circuit, a printed substrate including the circuit, a battery and a communication unit. The operating unit 1202 may be a button or a touch-sensitive response unit. The operating unit 1202 may be a biometric recognition unit, for example, which unlocks when a fingerprint is recognized. An electronic device including a communication unit may also be referred to as a communication device. The electronic device 1200 may further have a camera function by including a lens and an imaging element. The image captured by the camera function is displayed on the display unit 1201. Examples of the electronic device 1200 include smart phones and laptop computers.

[0341] Figure 4A and Figure 4B A schematic diagram showing an example of the display device according to this embodiment is shown. Figure 4A The display device 1300 includes a frame 1301 and a display portion 1302. The light emitting element according to this embodiment can be used in the display portion 1302. The display device 1300 includes a base 1303 that supports the frame 1301 and the display portion 1302. The base 1303 does not necessarily have to be Figure 4AThe form shown. The lower side of the frame 1301 can be used as a base. The frame 1301 and the display portion 1302 can be curved. The radius of curvature can be greater than 5000 mm and less than 6000 mm.

[0342] Figure 4B is a schematic diagram showing another example of the display device according to the embodiment. Figure 4B The display device 1310 in the embodiment is configured to be folded and is referred to as a foldable display device. The display device 1310 includes a first display portion 1311, a second display portion 1312, a housing 1313, and a bending point 1314. The first display portion 1311 and the second display portion 1312 may include a light-emitting element according to the embodiment. The first display portion 1311 and the second display portion 1312 may be seamless single-piece display devices. The first display portion 1311 and the second display portion 1312 may be divided by a bending point. The first display portion 1311 and the second display portion 1312 may display different images, or the first and second display portions may display a single image together.

[0343] Figure 5A 14 is a schematic diagram showing an example of a lighting device according to the embodiment. The lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, a filter 1404 configured to transmit light emitted from the light source 1402, and a light diffusion unit 1405. The light source 1402 may include an organic light emitting element according to the embodiment. The filter 1404 may be a filter for improving the color rendering of the light source. The light diffusion unit 1405 effectively diffuses the light from the light source and enables the light to reach a wide area for example, lighting. The filter 1404 and the light diffusion unit 1405 may be arranged on the light emitting side of the lighting device. If necessary, a cover may be arranged on the outermost side.

[0344] The lighting device is, for example, an indoor lighting device. The lighting device may emit white, daylight white, or any other color of light from blue to red. The lighting device may include a dimming circuit configured to dim. The lighting device may include an organic light emitting element according to the embodiment and a power supply circuit connected thereto. The power supply circuit is a circuit configured to convert an AC voltage into a DC voltage. White is a color with a color temperature of 4200K, and daylight white is a color with a color temperature of 5000K. The lighting device may include a color filter.

[0345] The lighting device according to this embodiment may also include a heat dissipation unit. The heat dissipation unit dissipates heat in the device to the outside and is composed of, for example, metal with high specific heat or liquid silicon.

[0346] Figure 5B15 is a schematic diagram of a car as an example of a moving body according to the embodiment. The car includes a tail light which is an example of a lamp. The car 1500 includes a tail light 1501, and the tail light 1501 can be configured to light up in response to, for example, a brake operation.

[0347] The tail lamp 1501 may include an organic light emitting element according to the embodiment. The tail lamp 1501 may include a protective member for protecting the organic light emitting element. The protective member may be made of any material having a certain degree of high strength and being transparent, but is preferably made of polycarbonate or the like. Polycarbonate may be mixed with a furandicarboxylic acid derivative or an acrylonitrile derivative or the like.

[0348] The car 1500 may include a car body 1503 and a window 1502 attached thereto. The window 1502 may be a transparent display unless it is a window for checking the front and rear of the car. The transparent display may include an organic light emitting element according to the embodiment. In this case, constituent materials of the organic light emitting element such as electrodes are composed of transparent members.

[0349] The mobile body according to this embodiment may be, for example, a ship, an aircraft, or a drone. The mobile body may include a body and a lamp arranged on the body. The lamp may emit light to allow the position of the body to be identified. The lamp includes an organic light emitting element according to this embodiment.

[0350] refer to Fig. 6A and Figure 6B An application example of the display device according to the above embodiment is described. The display device can be applied to a system that can be worn as a wearable device, such as smart glasses, HMD, and smart contact lenses. The camera and display device used in such an application example includes a camera device capable of photoelectric conversion of visible light and a display device capable of emitting visible light.

[0351] Fig. 6A is a schematic diagram showing an example of a wearable device according to an embodiment of the present invention. Fig. 6A Glasses 1600 (smart glasses) according to an application example are described. An imaging device 1602 such as a CMOS sensor or a SPAD is arranged on the surface side of a lens 1601 of the glasses 1600. A display device according to any of the above embodiments is provided on the back side of the lens 1601.

[0352] The glasses 1600 further include a controller 1603. The controller 1603 serves as a power source for supplying power to the camera 1602 and the display device. The controller 1603 controls the operations of the camera 1602 and the display device. The lens 1601 is provided with an optical system for focusing light onto the camera 1602.

[0353] Figure 6Bis a schematic diagram showing another example of a wearable device according to an embodiment of the present invention. Figure 7B The glasses 1610 (smart glasses) according to one application example are described. The glasses 1610 include a controller 1612, and the controller 1612 is equipped with Fig. 6A The image pickup device and the display device corresponding to the image pickup device 1602 in the image pickup device 1602 are provided in the lens 1611. The image pickup device in the controller 1612 and the optical system for projecting light emitted from the display device, and the image is projected onto the lens 1611. The controller 1612 serves as a power supply for supplying power to the image pickup device and the display device and also controls the operation of the image pickup device and the display device.

[0354] The controller 1612 may include a sight line detection unit configured to detect the sight line of the wearer. The sight line may be detected using infrared rays. The infrared light emitting unit emits infrared light to the eyeball of the user who is looking at the displayed image. The reflected light from the eyeball of the emitted infrared light is detected by the camera unit including a light receiving element, thereby obtaining a camera image of the eyeball. Due to the presence of a reduction unit that reduces the light from the infrared light emitting unit to the display unit in a plan view, the degradation of image quality is reduced. The user's sight line to the displayed image is detected from the captured image of the eyeball obtained by infrared light photography. Any known method may be used for sight line detection using the captured image of the eyeball. For example, a sight line detection method based on a Purkinje image formed by reflection of the irradiated light on the cornea may be used. More specifically, a sight line detection process based on the pupil-corneal reflection method is performed. Using the pupil-corneal reflection method, a sight line vector representing the direction (rotation angle) of the eyeball is calculated based on the pupil image and the Purkinje image included in the captured image of the eyeball, thereby detecting the user's sight line.

[0355] A display device according to an embodiment of the present invention may include a camera device having a light receiving element and may control a display image on the display device based on the line of sight information of the user from the camera device. Specifically, the display device determines a first viewing area that the user is gazing at and a second viewing area other than the first viewing area based on the line of sight information. The first viewing area and the second viewing area may be determined by a controller of the display device, or may be determined by an external controller and sent from the external controller. In the display area of ​​the display device, the display resolution of the first viewing area may be controlled to be higher than the display resolution of the second viewing area. That is, the resolution in the second viewing area may be set to be lower than the resolution in the first viewing area.

[0356] The display area includes a first display area and a second display area different from the first display area, and a high priority area is determined from the first display area and the second display area based on the line of sight information. The first viewing area and the second viewing area can be determined by a controller of the display device, or can be determined by an external controller and sent from the external controller. The resolution in the high priority area can be controlled to be higher than the resolution in areas other than the high priority area. That is, the resolution in the relatively low priority area can be set lower.

[0357] AI can be used to determine the first viewing area or a high priority area. AI can be a model configured to use an image of the eyeball and the actual sight direction of the eyeball in the image as teaching data and estimate the sight angle and the distance to the object being looked at from the image of the eyeball. The AI ​​program can be included in a display device, a camera device, or an external device. In the case of an external device, transmission to the display device via communication is performed.

[0358] When display control is performed based on visual recognition, it is suitable to use smart glasses that further include a camera device configured to capture external images. The smart glasses can display the captured external information in real time.

[0359] Fig. 7A 4 is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus 40 is an electrophotographic image forming apparatus and includes a photoreceptor 27, an exposure light source 28, a charging section 30, a developing section 31, a transfer section 32, a conveying roller 33, and a fixing section 35. The exposure light source 28 emits light 29 and forms an electrostatic latent image on the surface of the photoreceptor 27. The exposure light source 28 includes an organic light emitting element according to the embodiment. The developing section 31 contains a toner and the like. The charging section 30 charges the photoreceptor 27. The transfer section 32 transfers the developed image to a recording medium 34. The conveying roller 33 conveys the recording medium 34. The recording medium 34 is, for example, paper. The fixing section 35 fixes the image formed on the recording medium 34.

[0360] Figure 7B and Figure 7C Each shows an exposure light source 28 and each schematically shows how a plurality of light emitting portions 36 are arranged on a long substrate. Arrow 37 indicates a direction parallel to the axis of the photoreceptor and indicates the row direction in which the organic light emitting elements are arranged. The row direction is the same as the direction of the rotation axis of the photoreceptor 27. This direction may also be referred to as the long axis direction of the photoreceptor 27. Figure 7B In FIG. 2 , the light emitting section 36 is arranged along the long axis direction of the photoreceptor 27. Figure 7C In, with Figure 7BIn contrast, the light emitting sections 36 are alternately arranged in the row direction in the first row and the second row. The first row and the second row are located at different positions in the column direction. In the first row, a plurality of light emitting sections 36 are arranged at intervals. In the second row, the light emitting sections 36 are arranged at positions corresponding to the spaces between the light emitting sections 36 in the first row. That is, the plurality of light emitting sections 36 are also arranged at intervals in the column direction. Figure 7C The arrangement in may be referred to as, for example, a lattice arrangement, a staggered arrangement, or a checkered pattern.

[0361] As described above, the device using the organic light emitting element according to the embodiment can stably display with good image quality over a long period of time.

[0362] Example

[0363] The present invention will now be described with reference to examples. It should be noted that the present invention is not limited thereto.

[0364] The first organic compound, the second organic compound and the luminescent compound used in the light-emitting layer in the examples are shown below. The compounds used in the examples were synthesized with reference to Japanese Patent Application Publication No. 2012-72099, PCT Patent Application Publication No. 2013-518068, Japanese Patent Application Publication No. 2012-191031, U.S. Patent Application Publication No. 2010 / 0051928, International Publication No. 2010 / 050778, International Publication No. 2012 / 077582, International Publication No. 2011 / 136156, and German Patent Application Publication No. 10 2010 005 697.

[0365] [Chemical formula 41]

[0366]

[0367] Table 10 shows the HOMO level and LUMO level of the above compounds. The HOMO level is a value of the ionization potential determined as follows: for each compound, a 50 nm thick film was prepared by vacuum evaporation, and the film was measured using AC-3 manufactured by RIKEN KEIKI Co., Ltd. The LUMO level is a value determined as follows: the absorption spectrum of the film prepared in the same manner is measured, and the light absorption end is determined as a band gap, and then the band gap is subtracted from the ionization potential.

[0368] [Table 10]

[0369] Compound HOMO LUMO Z-1 -6.38 -2.92 Z-2 -6.40 -2.94 Z-3 -5.66 -3.11 Z-4 -5.91 -3.14 Z-5 -6.02 -3.10 Z-6 -5.73 -2.47 Z-7 -5.76 -2.72 Z-8 -6.11 -2.96 Z-9 -5.66 -2.72 Z-10 -5.63 -2.74 Z-11 -6.55 -3.42 Z-12 -6.43 -3.30 Z-13 -6.70 -3.65 Z-14 -6.38 -3.13 Z-15 -5.64 -2.71 Z-16 -6.10 -2.97 Z-17 -5.94 -2.96 Z-18 -5.95 -2.70 Z-19 -5.75 -3.26 Z-20 -6.12 -3.14 Z-21 -5.83 -2.37 Z-22 -5.82 -2.36 Blue-1 -5.98 -2.99 Red-1 -5.53 -3.31 Red-2 -5.46 -3.23 Red-3 -5.52 -3.25 Green-1 -5.87 -3.47 Green-2 -5.68 -3.04 Green-3 -5.08 -2.35 Green-4 -5.62 -2.95 Green-5 -5.62 -3.04

[0370] [Example 1]

[0371] In this embodiment, an organic light-emitting element having a top emission structure in which an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a cathode are sequentially formed on a substrate is produced.

[0372] A Ti film having a thickness of 40 nm was formed on a glass substrate by sputtering and patterned by photolithography to form an anode. 2 The resultant is then washed.

[0373] Subsequently, the substrate with electrodes produced above was attached to a vacuum evaporation apparatus (manufactured by ULVAC, Inc.). After preparing the evaporation material for evaporation, the apparatus was evacuated to a vacuum of 1.33×10 -4 Pa(1×10 -6 Torr). After that, UV / ozone cleaning was performed in the chamber. Subsequently, a layer having a layer structure shown in Table 11 was formed.

[0374] [Table 11]

[0375]

[0376] Thereafter, the substrate was transferred into a glove box and sealed with a glass cover containing a desiccant under a nitrogen atmosphere, thereby obtaining an organic light emitting element.

[0377] The obtained organic light emitting element was connected to a voltage applying device and its characteristics were evaluated. The current-voltage characteristics were measured by a microammeter 4140B manufactured by Hewlett-Packard Company, and the chromaticity was evaluated using an "SR-3" manufactured by TOPCON CORPORATION. The luminous brightness was measured by a BM7 manufactured by TOPCON CORPORATION. At 1000 cd / m 2 The external quantum efficiency (EQE) during the display period was 18%, indicating that the organic light-emitting element was a good organic green light-emitting element.

[0378] In addition, at 2000cd / m 2 The initial brightness was tested for continuous operation and the brightness degradation rate after 100 hours was determined. The results are shown in Tables 12-1 to 12-3.

[0379] (Examples 2 to 23, Comparative Examples 1 to 11)

[0380] Organic light-emitting elements were produced in the same manner as in Example 1, except that the composition of the light-emitting layer of Example 1 was changed as shown in Tables 12-1 to 12-3, and their characteristics were evaluated. The results are shown in Tables 12-1 to 12-3.

[0381] For EQE, when 1000cd / m 2 When the ratio of EQE during display relative to Example 1 was 0.1 or less, the rating was C, when the ratio of EQE was 0.1 or more and 0.9 or less, the rating was B, and when the ratio of EQE was 1.0 or more, the rating was A. The luminance degradation ratio is a value relative to Comparative Example 10 set to 1.0.

[0382] [Table 12-1]

[0383]

[0384] [Table 12-2]

[0385]

[0386] [Table 12-3]

[0387]

[0388] Comparison of Example 1 with Comparative Example 1 shows that EQE of Example 1 is higher. This is because in the present invention, a light-emitting compound is used and T1 of the first organic compound and the second organic compound is higher than T1 of the light-emitting compound. As shown in Comparative Example 2, even if a light-emitting compound is used relative to the first organic compound and the second organic compound of Comparative Example 2, the value of EQE is low because T1 of the first organic compound and the second organic compound is higher than T1 of the light-emitting compound.

[0389] Comparison of Example 2 with Comparative Examples 3 to 5 shows that Example 2 has an excellent luminance degradation ratio. Comparative Examples 3 to 5 have a two-component composition consisting of a first organic compound and a light-emitting compound, while Example 2 has a three-component composition consisting of a first organic compound, a second organic compound, and a light-emitting compound. The first organic compound has a skeleton showing hole transport properties, and the second organic compound has a skeleton showing electron transport properties. Thus, exciton generation on the light-emitting compound is suppressed, and thus the luminance degradation ratio of the organic light-emitting element of Example 2 is excellent.

[0390] Comparison of Example 3 with Comparative Example 6 shows that the brightness degradation ratio of Example 3 is excellent. This is due to the molecular structure of the first organic compound. In Z-21 of Example 3, all freely rotatable single bonds are carbon-carbon bonds, while in Z-22 of Comparative Example 6, a carbon-nitrogen bond is included as a freely rotatable single bond. As described above, the carbon-nitrogen bond has a lower binding energy than the carbon-carbon bond and therefore has poor binding stability. Therefore, the brightness degradation ratio of the organic light-emitting element of Example 3 is excellent.

[0391] Comparison of Example 1 with Example 3 shows that the brightness degradation ratio of Example 1 is more excellent. This is due to the molecular structure of the first organic compound. In Z-7 of Example 1, all freely rotatable single bonds are bonds between sp2 carbons. As described above, the binding energy of the bond between sp2 carbons is higher than the binding energy of the carbon-carbon bond, and thus provides even higher binding stability. Therefore, the brightness degradation ratio of the organic light emitting element of Example 1 is more excellent.

[0392] Comparison of Example 2 with Examples 4 to 6 shows that the brightness degradation ratio of Examples 4 and 5 is superior to that of Examples 2 and 6. Examples 4 and 5 are configured to have the configurations of Examples 2 and 6 and, in addition, further satisfy the relationship of formula (3). In other words, Examples 2 and Examples 4 to 6 are implementations of organic light-emitting elements having configurations (1 to 5). Therefore, in the organic light-emitting elements of Examples 4 and 5, compared with the organic light-emitting elements of Examples 2 and 6, hole capture on the light-emitting compound can be further suppressed, and thus exciton generation can be further suppressed from being concentrated on the light-emitting compound. Therefore, the brightness degradation ratio of the organic light-emitting elements of Examples 4 and 5 is superior.

[0393] Comparison of Example 7 with Example 8 shows that the brightness degradation ratio of Example 8 is more excellent. Example 7 is constructed to have the structure of Example 8 and, in addition, further satisfies the relationship of formula (4). In other words, Example 7 is an embodiment of an organic light-emitting element having a structure (1-6), and Example 8 is an embodiment of an organic light-emitting element having a structure (1-5). When the structure of formula (4) is satisfied, the absolute value of the LUMO energy level of the luminescent compound is the smallest, and thus electron capture on the luminescent compound can be further suppressed. Therefore, exciton generation can be further suppressed from being concentrated on the luminescent compound. Therefore, the brightness degradation ratio of the organic light-emitting element of Example 7 is more excellent.

[0394] Comparison of Example 2 with Example 9 shows that the brightness degradation ratio of Example 9 is more excellent. The organic light-emitting element of Example 9 has a composition that satisfies formula (1) and formula (3) to formula (5). In other words, Example 9 is an implementation scheme of an organic light-emitting element having a composition (1-7), that is, an organic light-emitting element having a minimum absolute value of the HOMO energy level of the first organic compound and a maximum absolute value of the LUMO energy level. Due to the above-mentioned composition, the capture of electrons and holes on the luminescent compound can be further suppressed. In addition, the generation rate of excitons in the first organic compound increases, so that the concentration of excitons on the luminescent compound can be suppressed, and therefore the brightness degradation ratio of the organic light-emitting element of Example 9 is more excellent.

[0395] Example 20 is an organic light-emitting element satisfying formulas (1) to (4). In other words, Example 20 is an embodiment of an organic light-emitting element having a composition (1-5) and a composition (1-6). When formulas (1) to (4) are satisfied, electrons or holes are not easily captured on the light-emitting compound, so the generation of excitons on the light-emitting compound can be suppressed, and thus the brightness degradation ratio of the organic light-emitting element of Example 20 is excellent.

[0396] (Examples 24 and 25)

[0397] Organic light emitting elements were produced in the same manner as in Example 1, and their characteristics were evaluated, except that the composition of the light emitting layer of Example 1 was changed as shown in Table 13. The results are shown in Table 13. The luminance degradation ratio is a ratio relative to Example 25 set to 1.0.

[0398] [Table 13]

[0399]

[0400] The organic light-emitting elements of Examples 24 and 25 have common compositions (1-1) to (1-5) and therefore have an excellent brightness degradation ratio. Specifically, the organic light-emitting element of Example 24 has compositions (1-1) to (1-5) and (1-7). Due to these compositions, the absolute value of the HOMO energy level of the first organic compound is the smallest, and the absolute value of the LUMO energy level is the largest, so it is possible to suppress the concentration of excitons on the luminescent compound. Therefore, the organic light-emitting element of Example 24 has a better brightness degradation ratio than the organic light-emitting element of Example 25.

[0401] (Examples 26 to 28 and Comparative Examples 12 and 13)

[0402] Organic light emitting elements were produced in the same manner as in Example 1, and their characteristics were evaluated, except that the composition of the light emitting layer of Example 1 was changed as shown in the following table. The results are shown in Table 14. The luminance degradation ratio is a ratio relative to Comparative Example 13 set to 1.0.

[0403] [Table 14]

[0404]

[0405] In the organic light-emitting elements of Comparative Examples 12 and 13, a carbon-nitrogen bond is included in the first organic compound as a freely rotatable single bond. As described above, the carbon-nitrogen bond has a low binding energy and thus has poor binding stability. In contrast, in the organic light-emitting elements of Examples 26 to 28, the freely rotatable single bond in the first organic compound is a carbon-carbon bond. Therefore, the organic light-emitting elements of Examples 26 to 28 have a more excellent brightness degradation ratio than Comparative Examples 12 and 13.

[0406] (Example 29)

[0407] In this embodiment, an organic light-emitting element with a top emission structure is produced, in which an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a first light-emitting layer, a second light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a cathode are sequentially formed on a substrate.

[0408] A Ti film having a thickness of 40 nm was formed on a glass substrate by sputtering and patterned by photolithography to form an anode. 2 The resultant is then washed.

[0409] Subsequently, the substrate with electrodes produced above was attached to a vacuum evaporation apparatus (manufactured by ULVAC, Inc.). After preparing the evaporation material for evaporation, the apparatus was evacuated to a vacuum of 1.33×10 -4 Pa(1×10 -6 Torr). After that, UV / ozone cleaning was performed in the chamber. Subsequently, a layer having a layer structure shown in Table 15 was formed.

[0410] [Table 15]

[0411]

[0412] Thereafter, the substrate was transferred into a glove box and sealed with a glass cover containing a desiccant under a nitrogen atmosphere, thereby obtaining an organic light emitting element.

[0413] The obtained organic light emitting element was connected to a voltage applying device and its characteristics were evaluated. The current-voltage characteristics were measured by a microammeter 4140B manufactured by Hewlett-Packard Company, and the chromaticity was evaluated using an "SR-3" manufactured by TOPCON CORPORATION. The luminous brightness was measured by a BM7 manufactured by TOPCON CORPORATION. The organic light emitting element was irradiated at 1000 cd / m 2 The display period is a good organic yellow light emitting element.

[0414] In addition, at 2000cd / m 2 The initial brightness of the continuous operation test was carried out, and the brightness degradation rate after 100 hours was determined. The results are shown in Table 16.

[0415] (Examples 30 to 32 and Comparative Example 14)

[0416] Organic light emitting elements were produced in the same manner as in Example 29, except that the composition of the light emitting layer of Example 29 was changed as shown in the following table, and their characteristics were evaluated.

[0417] [Table 16]

[0418]

[0419] In the organic light emitting element of Comparative Example 14, a carbon-nitrogen bond is included in the first organic compound as a freely rotatable single bond. As described above, the carbon-nitrogen bond has a low binding energy and thus has poor binding stability. In contrast, in the organic light emitting elements of Examples 29 to 32, the freely rotatable single bond in the first organic compound is a carbon-carbon bond. Therefore, the organic light emitting elements of Examples 29 to 32 have a more excellent brightness degradation ratio than Comparative Example 14.

[0420] The above shows that when two organic compounds in which the freely rotatable bonds are composed of carbon-carbon bonds are used to adjust the HOMO-LUMO relationship, charge capture on the luminescent compound can be suppressed. Therefore, exciton concentration is suppressed, thereby providing an organic light-emitting element with high luminous efficiency and high element durability. In addition, by applying the organic light-emitting element according to the present invention to various light-emitting devices, display devices and lamps with good luminous properties and high element durability can be obtained.

[0421] The present invention may also have the following configurations.

[0422] (Composition 1)

[0423] An organic light emitting element, comprising:

[0424] a first electrode and a second electrode; and

[0425] an organic compound layer disposed between the first electrode and the second electrode,

[0426] wherein the organic compound layer includes a light-emitting layer,

[0427] The light-emitting layer contains at least a first organic compound, a second organic compound, and a phosphorescent light-emitting compound.

[0428] The lowest excited triplet energy of the first organic compound and the second organic compound is higher than the lowest excited triplet energy of the luminescent compound,

[0429] All freely rotatable single bonds in the first organic compound are carbon-carbon bonds, and

[0430] The organic light emitting element satisfies the relationship of formula (1):

[0431] |HOMO (H2)| > |HOMO (H1)| (1).

[0432] In formula (1), HOMO(H1) and HOMO(H2) represent the HOMO of the first organic compound and the HOMO of the second organic compound, respectively.

[0433] (Composition 2)

[0434] According to the organic light emitting element of configuration 1, the organic light emitting element further satisfies the relationship of formula (2):

[0435] |LUMO (H2)| > |LUMO (D)| (2).

[0436] In formula (2), LUMO(H2) and LUMO(D) represent the LUMO of the second organic compound and the LUMO of the light-emitting compound, respectively.

[0437] (Composition 3)

[0438] According to the organic light-emitting element of configuration 1 or 2, the organic light-emitting element further satisfies the relationship of formula (3):

[0439] |LUMO (H1)| > |LUMO (D)| (3).

[0440] In formula (3), LUMO(H1) represents the LUMO of the first organic compound.

[0441] (Composition 4)

[0442] The organic light-emitting element according to any one of configurations 1 to 3, wherein the organic light-emitting element further satisfies the relationship of formula (4):

[0443] |LUMO (H1)| > |LUMO (H2)| (4).

[0444] (Composition 5)

[0445] The organic light-emitting element according to any one of configurations 1 to 4, wherein the organic light-emitting element further satisfies the relationship of formula (5):

[0446] |HOMO (D)| > |HOMO (H1)| (5).

[0447] In formula (5), HOMO(D) and HOMO(H1) represent the HOMO of the light-emitting compound and the HOMO of the first organic compound, respectively.

[0448] (Composition 6)

[0449] The organic light emitting element according to any one of Configurations 1 to 5, wherein all freely rotatable single bonds in the first organic compound are bonds between sp2 carbons.

[0450] (Composition 7)

[0451] The organic light emitting element according to any one of Configurations 1 to 6, wherein all freely rotatable single bonds in the second organic compound are carbon-carbon bonds.

[0452] (Composition 8)

[0453] An organic light-emitting element according to any one of Configurations 1 to 7, wherein all freely rotatable single bonds in the second organic compound are bonds between sp2 carbons.

[0454] (Composition 9)

[0455] The organic light-emitting element according to any one of Configurations 1 to 8, wherein the first organic compound has a skeleton represented by General Formula (1-1) or (1-2).

[0456] [Chemical formula 42]

[0457]

[0458] In the general formulae (1-1) and (1-2), the cyclic units A to C are each independently selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups. Q1 to Q3 are each independently selected from direct bonds, C(R A )(R B )、N(R C ), oxygen atoms, sulfur atoms, selenium atoms and tellurium atoms. A To R C Each is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group. R3 and the adjacent one of the cyclic units A to C form a ring together.

[0459] (Composition 10)

[0460] The organic light-emitting element according to any one of Configurations 1 to 9, wherein the first organic compound has a skeleton represented by any of the following structural formulas.

[0461] [Chemical formula 43]

[0462]

[0463] (Composition 11)

[0464] The organic light-emitting element according to any one of Configurations 1 to 10, wherein the second organic compound has a skeleton represented by any one of General Formulae (2-1) to (2-7).

[0465] [Chemical formula 44]

[0466]

[0467] In the general formulae (2-1) and (2-2), the cyclic units D to F are each independently selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups. Q4 is each independently selected from direct bonds, C(R D )(R E ), oxygen atoms, sulfur atoms, selenium atoms and tellurium atoms. D and R E Each is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group. n is an integer of 1 to 5.

[0468] In the general formulas (2-3) to (2-7), R1 to R 20 R1 to R2 are each independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, and a substituted or unsubstituted aryl group. 20 In the above-mentioned formula (I), adjacent substituents may be bonded together to form a condensed ring.

[0469] (Composition 12)

[0470] The organic light-emitting element according to any one of Configurations 1 to 11, wherein the second organic compound has a skeleton represented by any of the following structural formulas.

[0471] [Chemical formula 45]

[0472]

[0473] (Composition 13)

[0474] The organic light emitting element according to any one of claims 1 to 12, wherein the organic compound layer is composed of a plurality of layers,

[0475] The plurality of layers are composed of at least a light-emitting layer and a second layer different from the light-emitting layer,

[0476] The second layer comprises at least one organic compound, and

[0477] The lowest excited triplet energy of the organic compound is higher than the lowest excited triplet energy of the first organic compound and the second organic compound.

[0478] (Composition 14)

[0479] The organic light-emitting element according to any one of Configurations 1 to 13, wherein the light-emitting layer is a first light-emitting layer,

[0480] A second light-emitting layer different from the first light-emitting layer is further arranged between the first light-emitting layer and the first electrode or between the first light-emitting layer and the second electrode, and

[0481] The second light emitting layer emits light having a color different from the color of light emitted from the first light emitting layer.

[0482] (Composition 15)

[0483] A display device includes a plurality of pixels, wherein at least one of the plurality of pixels includes the organic light emitting element according to any one of Configurations 1 to 14 and a transistor connected to the organic light emitting element.

[0484] (Composition 16)

[0485] A photoelectric conversion device comprising: an optical section including a plurality of lenses; an imaging element configured to receive light passing through the optical section; and a display section configured to display an image captured by the imaging element,

[0486] The display unit includes the organic light-emitting element according to any one of Configurations 1 to 14.

[0487] (Composition 17)

[0488] An electronic device includes: a display unit including the organic light-emitting element according to any one of Configurations 1 to 14; a housing provided with the display unit; and a communication unit provided in the housing and configured to communicate with an external device.

[0489] (Composition 18)

[0490] A lighting device comprising: a light source including the organic light emitting element according to any one of configurations 1 to 14; and a light diffusion portion or an optical film configured to transmit light emitted from the light source.

[0491] (Composition 19)

[0492] A mobile object, comprising: a lamp including an organic light emitting element according to any one of configurations 1 to 14; and a body provided with the lamp.

[0493] (Composition 20)

[0494] An image forming device comprising: a photosensitive body; and an exposure light source configured to expose the photosensitive body,

[0495] The exposure light source includes an organic light-emitting element according to any one of Configurations 1 to 14.

[0496] The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the spirit and scope of the present invention. Therefore, the following claims are attached to disclose the scope of the present invention.

[0497] This application claims the benefit of Japanese Patent Application No. 2022-102760, filed on Jun. 27, 2022, which is hereby incorporated by reference herein in its entirety.

[0498] Reference numerals list

[0499] 1 substrate

[0500] 2Reflective electrode

[0501] 3. Insulation layer

[0502] 4 Organic compound layer

[0503] 5. Light Extraction Electrode

[0504] 6 Sealing layer

[0505] 7 Color Filters

[0506] 10 Light-emitting elements

[0507] 11 substrate

[0508] 12 moisture-proof layers

[0509] 13Gate electrode

[0510] 14Gate insulating film

[0511] 15Semiconductor layer

[0512] 16 Drain electrode

[0513] 17 Source electrode

[0514] 18 TFT components

[0515] 19 Insulation film

[0516] 20 contact holes

[0517] 21 Anode

[0518] 22Organic compound layer

[0519] 23 cathode

[0520] 24First protective layer

[0521] 25 Second protection layer

[0522] 1000 display devices

[0523] 1001 Upper cover

[0524] 1002 Flexible Printed Circuit

[0525] 1003 Touch Panel

[0526] 1004 Flexible Printed Circuit

[0527] 1005 Display Panel

[0528] 1006 Frame

[0529] 1007 Circuit Board

[0530] 1008 Battery

[0531] 1009 lower cover

[0532] 1100 Camera Equipment

[0533] 1101 Viewfinder

[0534] 1102 Back display

[0535] 1103 Operation Department

[0536] 1104 housing

[0537] 1200 Electronic equipment

[0538] 1201 Display Department

[0539] 1202 Operation Department

[0540] 1203 housing

[0541] 1300 display devices

[0542] 1301 Framework

[0543] 1302 Display Unit

[0544] 1303 base

[0545] 1310 Display Device

[0546] 1311 First display unit

[0547] 1312 Second display unit

[0548] 1313 Shell

[0549] 1314 bending point

[0550] 1500 cars

[0551] 1501 Tail Light

[0552] 1502 Window

[0553] 1503 Carbody

Claims

1. An organic light emitting element, comprising: a first electrode and a second electrode; and an organic compound layer disposed between the first electrode and the second electrode, wherein the organic compound layer comprises a light-emitting layer, The light-emitting layer contains at least a first organic compound, a second organic compound and a phosphorescent light-emitting compound. The lowest excited triplet energy of the first organic compound and the second organic compound is higher than the lowest excited triplet energy of the luminescent compound, All freely rotatable single bonds in the first organic compound are carbon-carbon bonds, and The organic light emitting element satisfies the relationship of formula (1): |HOMO (H2)| > |HOMO (H1)| (1) In formula (1), HOMO (H1) and HOMO (H2) represent the HOMO of the first organic compound and the HOMO of the second organic compound, respectively.

2. The organic light emitting element according to claim 1, wherein the organic light emitting element further satisfies the relationship of formula (2): |LUMO (H2)| > |LUMO (D)| (2) In formula (2), LUMO(H2) and LUMO(D) represent the LUMO of the second organic compound and the LUMO of the luminescent compound, respectively.

3. The organic light emitting element according to claim 1, wherein the organic light emitting element further satisfies the relationship of formula (3): |LUMO (H1)| > |LUMO (D)| (3) In formula (3), LUMO(H1) represents the LUMO of the first organic compound.

4. The organic light emitting element according to claim 1, wherein the organic light emitting element further satisfies the relationship of formula (4): |LUMO (H1)| > |LUMO (H2)| (4).

5. The organic light emitting element according to claim 1, wherein the organic light emitting element further satisfies the relationship of formula (5): |HOMO (D)| > |HOMO (H1)| (5) In formula (5), HOMO(D) and HOMO(H1) represent the HOMO of the luminescent compound and the HOMO of the first organic compound, respectively.

6. The organic light-emitting element according to claim 1, wherein the organic light-emitting element further satisfies the relationship between formula (2) and formula (3): |LUMO (H2)| > |LUMO (D)| (2) |LUMO (H1)| > |LUMO (D)| (3).

7. The organic light-emitting element according to claim 1, wherein the organic light-emitting element further satisfies the relationship between formula (2) and formula (4): |LUMO (H2)| > |LUMO (D)| (2) |LUMO (H1)| > |LUMO (H2)| (4).

8. The organic light-emitting element according to claim 1, wherein the organic light-emitting element further satisfies the relationship of formula (2) to formula (4): |LUMO (H2)| > |LUMO (D)| (2) |LUMO (H1)| > |LUMO (D)| (3) |LUMO (H1)| > |LUMO (H2)| (4).

9. The organic light-emitting element according to claim 1, wherein the organic light-emitting element further satisfies the relationship of formula (3) to formula (5): |LUMO (H1)| > |LUMO (D)| (3) |LUMO (H1)| > |LUMO (H2)| (4) |HOMO (D)| > |HOMO (H1)| (5).

10. The organic light emitting element according to claim 1, wherein all freely rotatable single bonds in the first organic compound are bonds between sp2 carbons. 11 . The organic light emitting element according to claim 1 , wherein all freely rotatable single bonds in the second organic compound are carbon-carbon bonds. 12 . The organic light emitting element according to claim 11 , wherein all freely rotatable single bonds in the second organic compound are bonds between sp2 carbons.

13. The organic light-emitting element according to claim 1, wherein the first organic compound has a skeleton represented by the general formula (1-1) or (1-2): [Chemical formula 1] in, In the general formulae (1-1) and (1-2), the cyclic units A to C are each independently selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups; Q1 to Q3 are each independently selected from direct bonds, C(R A )(R B )、N(R C ), oxygen atoms, sulfur atoms, selenium atoms and tellurium atoms; R A To R C are each independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heteroaryl group; and R C Together with an adjacent one of the cyclic units A to C, a ring is formed.

14. The organic light-emitting element according to claim 13, wherein the first organic compound has a skeleton represented by any of the following structural formulas: [Chemical formula 2] 15. The organic light-emitting element according to claim 1, wherein the second organic compound has a skeleton represented by any of the general formulas (2-1) to (2-7): [Chemical formula 3] In the general formulae (2-1) and (2-2), the cyclic units D to F are each independently selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heteroaryl groups; Q4 is each independently selected from direct bonds, C(R D )(R E ), oxygen atoms, sulfur atoms, selenium atoms and tellurium atoms; R D and R E are each independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heteroaryl group; and n is an integer from 1 to 5, and In the general formulae (2-3) to (2-7), R1 to R 20 are each independently selected from a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, and a substituted or unsubstituted aryl group; and in R1 to R 20 In the above-mentioned formula (I), adjacent substituents may be bonded together to form a condensed ring.

16. The organic light-emitting element according to claim 15, wherein the second organic compound has a skeleton represented by any of the following structural formulas: [Chemical formula 4] 17. The organic light emitting element according to claim 1, wherein the organic compound layer is composed of a plurality of layers, The plurality of layers are composed of at least a light-emitting layer and a second layer different from the light-emitting layer, The second layer comprises at least one organic compound, and The lowest excited triplet energy of the organic compound is higher than the lowest excited triplet energy of the first organic compound and the second organic compound.

18. The organic light emitting element according to claim 1, wherein the light emitting layer is a first light emitting layer, A second light-emitting layer different from the first light-emitting layer is further arranged between the first light-emitting layer and the first electrode or between the first light-emitting layer and the second electrode, and The second light emitting layer emits light having a color different from a color of light emitted from the first light emitting layer. 19 . A display device comprising a plurality of pixels, wherein at least one of the plurality of pixels comprises the organic light emitting element according to any one of claims 1 to 18 and a transistor connected to the organic light emitting element.

20. A photoelectric conversion device, comprising: An optical section including a plurality of lenses; an imaging element configured to receive light passing through the optical section; and a display unit configured to display an image captured by the imaging element, The display unit includes the organic light emitting element according to any one of claims 1 to 18.

21. An electronic device, comprising: A display unit comprising the organic light emitting element according to any one of claims 1 to 18; A housing provided with the display unit; and a communication unit provided in the housing and configured to communicate with the outside.

22. A lighting device comprising: A light source comprising an organic light emitting element according to any one of claims 1 to 18; and a light diffusion portion or an optical film configured to transmit light emitted from the light source.

23. A mobile object, comprising: A lamp comprising an organic light-emitting element according to any one of claims 1 to 18; And a body provided with the lamp.

24. An image forming apparatus comprising: Photoreceptor; and an exposure light source configured to expose the photosensitive body, The exposure light source comprises the organic light emitting element according to any one of claims 1 to 18.

Images