Light-emitting composition, method for producing organic light-emitting element, organic light-emitting element, display device, imaging device, electronic apparatus, lighting device, and mobile body

Abstract

This light-emitting composition is characterized by comprising a compound represented by general formula (1-1), a compound represented by general formula (2), and an organic solvent. At least one of R1 to R3 in general formula (1-1) represents a group represented by general formula (1-2). The c-ring in general formula (1-2) is a heteroaryl ring containing an atom of a group 16 element. At least one of R11 to R20 in general formula (2) is a heteroaryl group containing an atom of a group 16 element.

Description

Luminescent composition, method for manufacturing organic light-emitting elements, organic light-emitting elements, display device, imaging device, electronic device, lighting device, and mobile body

[0001] This disclosure relates to luminescent compositions, methods for manufacturing organic light-emitting elements, organic light-emitting elements, display devices, imaging devices, electronic devices, lighting devices, and mobile bodies.

[0002] An organic light-emitting device is an electronic element having a pair of electrodes, consisting of a first electrode and a second electrode, and an organic compound layer placed between these electrodes. By injecting electrons and holes from the pair of electrodes into the organic compound layer, the light-emitting organic compound in the organic compound layer can be activated from the ground state to an excited state. Then, when the excited organic compound returns to the ground state, it can release excess energy as light.

[0003] Organic light-emitting devices are also called organic electroluminescent elements or organic EL elements. Organic light-emitting devices can generally be manufactured by dry processes such as vacuum deposition, in which materials for forming various functional layers such as organic compound layers, inorganic compound layers, and electrodes (layers) are heated and deposited onto a substrate under high vacuum. On the other hand, due to the difficulty of uniform deposition on large-area substrates, and from the viewpoint of material utilization efficiency and manufacturing costs, methods for manufacturing organic light-emitting devices by wet processes such as printing have also been investigated in recent years. In the printing method, an organic light-emitting device is manufactured by applying a liquid light-emitting composition to a substrate.

[0004] As a luminescent composition, Patent Document 1 describes a composition for forming a luminescent layer that includes compound 1-A and compound 1-B, represented by the following chemical formulas, and an organic solvent.

[0005]

[0006] International Publication No. 2016 / 152418

[0007] The present inventors fabricated an organic light-emitting device using the light-emitting composition described in Patent Document 1 and investigated its various properties. As a result, it was found that the color purity of the light emission was good, but there was room for improvement in the luminescence efficiency.

[0008] Therefore, an object of the present disclosure is to provide a light-emitting composition capable of forming an organic compound layer excellent in color purity and luminous efficiency. Another object of the present disclosure is to provide a method for manufacturing an organic light-emitting device using the above light-emitting composition. Still another object of the present disclosure is to provide an organic light-emitting device excellent in color purity and luminous efficiency, and a display device, an imaging device, an electronic device, a lighting device, and a moving body using the organic light-emitting device.

[0009] That is, according to the present disclosure, there is provided a light-emitting composition characterized by containing a compound represented by the following general formula (1-1), a compound represented by the following general formula (2), and an organic solvent.

[0010] (In the general formula (1-1), ring a and ring b each independently represent an aryl ring or a heteroaryl ring, and at least one hydrogen atom in these rings may be a deuterium atom, a halogen atom, a cyano group, or an alkyl group, an aryl group, a heteroaryl group, an amino group, an alkoxy group, an aryloxy group, a heteroaryloxy group, or a silyl group which may have a substituent. X １ and X ２ each independently represent an oxygen atom, a sulfur atom, or N-R ６ represents. R ６ represents an aryl group, a heteroaryl group, or an alkyl group which may have a substituent, and may be bonded to ring a in the case of X １ and to ring b in the case of X ２ through a linking group or a single bond. R １ to R ３ each independently represent a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, or an alkyl group, an aryl group, a heteroaryl group, or a group represented by the general formula (1-2) which may have a substituent. However, at least one of R １ to R ３ represents a group represented by the general formula (1-2). In the general formula (1-2), ring c represents a heteroaryl ring containing an atom of Group 16 elements, and X ３represents an oxygen atom or a sulfur atom, and * represents the bonding position with the general formula (1-1).)

[0011] (In the general formula (2), R １１ to R ２０ each independently represents a hydrogen atom, or an alkyl group, an aryl group, or a heteroaryl group which may have a substituent. However, at least one of R １１ to R ２０ is a heteroaryl group containing an atom of Group 16 elements which may have a substituent.)

[0012] According to the present disclosure, a light-emitting composition capable of forming an organic compound layer excellent in color purity and luminous efficiency can be provided. Further, according to another aspect of the present disclosure, a method for manufacturing an organic light-emitting device using the above light-emitting composition can be provided. Furthermore, according to another aspect of the present disclosure, an organic light-emitting device excellent in color purity and luminous efficiency, and a display device, an imaging device, an electronic device, a lighting device, and a moving body using the organic light-emitting device can be provided.

[0013] It is a schematic cross-sectional view showing an example of a pixel constituting the display device of the present disclosure. It is a schematic cross-sectional view showing one embodiment of the display device of the present disclosure. It is a schematic diagram showing another embodiment of the display device of the present disclosure. It is a schematic diagram showing an example of an imaging device. It is a schematic diagram showing an example of a portable device. It is a schematic diagram showing another embodiment of the display device of the present disclosure. It is a schematic diagram showing another embodiment of the display device of the present disclosure. It is a schematic diagram showing an example of a lighting device. It is a schematic diagram showing an example of a moving body. It is a schematic diagram showing an example of a wearable device. It is a schematic diagram showing another example of a wearable device.

[0014] Hereinafter, preferred embodiments will be given to explain the present disclosure in more detail. The present disclosure is not limited to the following description, and various changes can be made to its form and details without departing from the spirit and scope of the present disclosure. That is, the present disclosure should not be construed as being limited by the following description. Physical property values are values at normal temperature (25 ° C) and normal pressure (1 atm) unless otherwise specified. Further, the "average film thickness" means the average thickness of each layer (film) in the region that emits light when a voltage is applied to the organic light-emitting device. The "light-emitting composition" may be one in which the composition itself emits light, or one in which a member formed by the composition emits light. The "light-emitting composition" is described in this inclusive sense. Further, in General Formula (1-1) and General Formula (2), "may have a substituent" means that the functional group is "substituted or unsubstituted".

[0015] The present inventors have variously studied a light-emitting composition capable of forming an organic compound layer excellent in color purity and luminous efficiency. As a result, it has been found that the above effects can be obtained by a light-emitting composition containing a compound represented by General Formula (1-1) described later, a compound represented by General Formula (2) described later, and an organic solvent. The present inventors presume the mechanism by which an organic compound layer excellent in color purity and luminous efficiency can be formed by this light-emitting composition as follows.

[0016] When an organic compound layer is formed by applying a light-emitting composition containing an emitter material and a host material by a wet process such as a printing method, in the drying process of the light-emitting composition, the distribution of the emitter material and the host material in the light-emitting composition tends to be biased. If a film is formed with the distribution being biased, the energy transfer from the host material to the emitter material becomes less likely to occur compared to the case where the distribution is uniform, and the luminous efficiency decreases. Therefore, it is desirable to improve the compatibility between the emitter material and the host material.

[0017] The compound represented by general formula (1-1) is a polycyclic aromatic compound and is an emitter material that exhibits high color purity luminescence. As explained later regarding general formula (1-1), the compound represented by general formula (1-1) contains multiple heteroatoms and is therefore a highly polar compound. An example of a host material used with this emitter material is anthracene compound. An advantage of using anthracene compounds as a host material is that the luminescence efficiency of the organic light-emitting element is improved due to the TTF (Triple-Triple Fusion) phenomenon.

[0018] In this disclosure, a compound represented by general formula (2) is used as the host material. As described below for general formula (2), the compound represented by general formula (2) is an anthracene compound having a heteroaryl group containing an atom of a group 16 element. Because the group 16 element atom in the compound represented by general formula (2) is negatively charged, it has higher polarity compared to anthracene compounds that do not have a heteroaryl group containing an atom of a group 16 element. In addition, because the group 16 element atom has a valence of 2 (two bonding bonds), the space around the atom is empty, and it readily interacts with surrounding polar molecules. For these reasons, the compound represented by general formula (2) has good compatibility with the compound represented by general formula (1-1).

[0019] Furthermore, as explained later regarding general formula (1-1), the compound represented by general formula (1-1) also has a heteroaryl ring containing an atom of a Group 16 element. In other words, in this disclosure, a polycyclic aromatic compound having a heteroaryl ring containing an atom of a Group 16 element, represented by general formula (1-1), is used as the emitter material. Compounds having substituents with similar structures are easily compatible with each other. Since both the compound represented by general formula (1-1) and the compound represented by general formula (2) have a heteroaryl group containing an atom of a Group 16 element, they have good compatibility.

[0020] Therefore, by forming an organic compound layer using a luminescent composition containing an emitter material represented by general formula (1-1), a host material represented by general formula (2), and an organic solvent, the uneven distribution of the emitter material and host material that occurs during the drying process can be suppressed. As a result, an organic compound layer with excellent color purity and luminescence efficiency can be formed.

[0021] <Luminescent Composition> A luminescent composition according to one embodiment of the present disclosure (hereinafter sometimes simply referred to as "luminescent composition") contains a compound represented by general formula (1-1), a compound represented by general formula (2), and an organic solvent. In this disclosure, "compound represented by general formula (1-1)," "compound represented by general formula (2)," and "organic solvent" may be referred to as "first component," "second component," and "third component," respectively. The components and physical properties of the luminescent composition of this embodiment will be described in detail below.

[0022] (First component) The luminescent composition contains a compound represented by the following general formula (1-1). The luminescent composition may contain one or more compounds represented by the following general formula (1-1).

[0023]

[0024] In general formula (1-1), the a-ring and the b-ring each independently represent an aryl ring or a heteroaryl ring. At least one hydrogen atom in these rings may be substituted with a deuterium atom, a halogen atom, a cyano group, or an alkyl group, aryl group, heteroaryl group, amino group, alkoxy group, aryloxy group, or silyl group, which may have substituents. １ and X ２ These are, independently, an oxygen atom, a sulfur atom, or N-R ６ Represents R ６ represents an aryl group, heteroaryl group, or alkyl group which may have substituents, and is linked by a linking group or single bond, X １ In this case, ring a and X ２ In this case, it may be bonded to the b-ring. １ ~R ３Each of these independently represents a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, or an alkyl group, aryl group, heteroaryl group, or group represented by general formula (1-2), which may have a substituent. However, R １ ~R ３ At least one of these represents a group represented by general formula (1-2). In general formula (1-2), the c ring represents a heteroaryl ring containing an atom of a group 16 element, and X ３ represents an oxygen atom or a sulfur atom. Also, * represents the bonding position with the general formula (1-1) above. In other words, * represents R in general formula (1-1) １ , R ２ , or R ３ This represents a bonding operation in [the context of the game].

[0025] In this disclosure, the ring structure of the aryl ring preferably has 5 to 20 carbon atoms, and more preferably has 6 to 12 carbon atoms. Examples of aryl ring structures include benzene rings, naphthalene rings, indene rings, fluorene rings, phenanthrene rings, triphenylene rings, pyrene rings, anthracene rings, perylene rings, chrysene rings, and fluorantene rings.

[0026] Furthermore, the ring structure of the heteroaryl ring preferably has 3 to 24 carbon atoms, more preferably 3 to 18 carbon atoms, and even more preferably 3 to 12 carbon atoms. Examples of heteroaryl ring structures include pyridine rings, pyrimidine rings, pyrazine rings, triazine rings, benzofuran rings, benzothiophene rings, dibenzofuran rings, dibenzothiophene rings, oxazoline rings, oxadiazoline rings, thiazoline rings, thiadiazole rings, carbazoline rings, acridine rings, and phenanthroline rings.

[0027] In this disclosure, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0028] The alkyl group preferably has 1 to 40 carbon atoms, more preferably 1 to 20 carbon atoms, and even more preferably 1 to 10 carbon atoms. Examples of alkyl groups include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, secondary butyl group, octyl group, cyclohexyl group, tert-pentyl group, 3-methylpentan-3-yl group, 1-adamantyl group, and 2-adamantyl group.

[0029] The aryl group preferably has 5 to 20 carbon atoms, and more preferably 6 to 12 carbon atoms. Examples of aryl groups include phenyl, naphthyl, indenyl, biphenyl, triphenyl, fluorenyl, phenanthryl, triphenylenyl, pyrenyl, anthracenyl, perilenyl, chrysenyl, and fluoranthenyl groups.

[0030] The heteroaryl group preferably has 3 to 24 carbon atoms, more preferably 3 to 18 carbon atoms, and even more preferably 3 to 12 carbon atoms. Examples of heteroaryl groups include pyridyl, pyrimidyl, pyrazyl, triazyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, oxazolyl, oxadiazolyl, thiazolyl, thiadiazolyl, carbazolyl, acridinyl, and phenanthrolyl groups.

[0031] The amino group is preferably a substituted amino group substituted with an alkyl group or an aryl group, and more preferably a substituted amino group substituted with an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. Examples of substituted amino groups include N-methylamino group, N-ethylamino group, N,N-dimethylamino group, N,N-diethylamino group, N-methyl-N-ethylamino group, N-benzylamino group, N-methyl-N-benzylamino group, N,N-dibenzyloamino group, anilino group, N,N-diphenylamino group, N,N-dinaphthylamino group, N,N-difluorenylamino group, N-phenyl-N-tolylamino group, N,N-ditolylamino group, N-methyl-N-phenylamino group, N,N-dianisorylamino group, N-mesityl-N-phenylamino group, N,N-dimesitylamino group, N-phenyl-N-(4-tert-butylphenyl)amino group, N-phenyl-N-(4-trifluoromethylphenyl)amino group, and N-piperidyl group.

[0032] The alkoxy group preferably has 1 to 40 carbon atoms, more preferably 1 to 20 carbon atoms, and even more preferably 1 to 10 carbon atoms. Examples of alkoxy groups include methoxy, ethoxy, propoxy, 2-ethyl-octyloxy, and benzyloxy groups.

[0033] Examples of aryloxy groups include phenoxy groups.

[0034] Examples of heteroaryloxy groups include the thienyloxy group.

[0035] Examples of silyl groups include the trimethylsilyl group and the triphenylsilyl group.

[0036] Examples of substituents that the alkyl, aryl, heteroaryl, amino, alkoxy, aryloxy, heteroaryloxy, and silyl groups mentioned above may further have include halogen atoms; alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, and tert-butyl groups; alkoxy groups such as methoxy, ethoxy, and propoxy groups; amino groups such as dimethylamino, diethylamino, dibenzylamino, diphenylamino, and ditolylamino groups; aryloxy groups such as phenoxy groups; aryl groups such as phenyl and biphenyl groups; heteroaryl groups such as pyridyl and pyrrolyl groups; cyano groups; and so on.

[0037] Next, regarding the compound represented by general formula (1-1), preferred configurations and other aspects related to general formula (1-1) will be described from the viewpoint of easily obtaining a luminescent composition capable of forming an organic compound layer with excellent color purity and luminescence efficiency.

[0038] In general formula (1-1), the a-ring and b-ring, which represent an aryl ring or heteroaryl ring that may have substituents, may be monocyclic or polycyclic (fused) rings. The ring structure of the a-ring in general formula (1-1) is preferably an aryl ring that may have substituents, more preferably a benzene ring or fluorene ring that may have substituents, and even more preferably a benzene ring or fluorene ring that has substituents. The substituents in these ring structures are preferably at least one of alkyl groups and aryl groups, more preferably an alkyl group or a phenyl group, and even more preferably an alkyl group. The ring structure of the b-ring in general formula (1-1) is preferably a benzene ring, a dibenzofuran ring, or a dibenzothiophene ring that may have substituents. The ring structure of the b-ring is more preferably a dibenzofuran ring or a dibenzothiophene ring that may have substituents, and even more preferably an unsubstituted dibenzofuran ring or dibenzothiophene ring.

[0039] X in general formula (1-1) １ N-R ６ It is preferable to represent R. ６R is preferably an aryl group, a heteroaryl group, or an alkyl group, which may have substituents. ６ More preferably, the group is an aryl group which may have a substituent, more preferably a phenyl group or fluorenyl group which may have a substituent, and particularly preferably a phenyl group or fluorenyl group which has a substituent. As substituents on these groups, at least one of alkyl groups and aryl groups is preferred, an alkyl group or a phenyl group is more preferred, and an alkyl group is even more preferred. Also, X in general formula (1-1) ２ It is preferable that it is an oxygen atom.

[0040] R in general formula (1-1) １ ~R ３ For example, R １ and R ３ However, each is preferably independently a hydrogen atom or an alkyl group, R ２ It is preferable that the group is represented by the general formula (1-2). Among the groups represented by the general formula (1-2), the group 16 element atom in the c ring, which is a heteroaryl ring, is preferably an oxygen atom or a sulfur atom, and X ３ It is preferable that the element is an oxygen atom. In particular, the ring structure of the c-ring is more preferably a dibenzothiophene ring or a dibenzofuran ring, and it is even more preferable that these ring structures are of the same type as the b-ring described above.

[0041] Furthermore, general formula (1-1) may also be general formula (1-3) as shown below. That is, the compound represented by general formula (1-1) may contain the compound represented by general formula (1-3) as shown below, and the luminescent composition may contain the compound represented by general formula (1-3) as the compound represented by general formula (1-1).

[0042]

[0043] In general formula (1-3), the d-ring represents an aryl ring or heteroaryl ring which may have substituents, and the e-ring represents a heteroaryl ring containing an atom of a group 16 element. ４ and R ５Each of these independently represents a hydrogen atom, a deuterium atom, or an alkyl group, aryl group, or heteroaryl group which may have a substituent. ２ represents an oxygen atom or a sulfur atom. a ring, and R １ ~R ３ These are all equivalent to those in the general formula (1-1) above.

[0044] In general formula (1-3), the d-ring, which may have substituents, represents an aryl ring or heteroaryl ring and may be a monocyclic or polycyclic (fused) ring. The d-ring is preferably an aryl ring which may have substituents. Among these, a benzene ring (phenyl group) or a fluorene ring (fluorenyl group) which may have substituents is more preferred, and a benzene ring (phenyl group) or a fluorene ring (fluorenyl group) which has substituents is even more preferred. The substituents on these rings (groups) are preferably at least one of alkyl groups and aryl groups, with alkyl groups or phenyl groups being more preferred, and alkyl groups being even more preferred.

[0045] In general formula (1-3), the e-ring, which represents a heteroaryl ring containing an atom of the 16th element, may be a mono-ring structure or a poly-ring (fused ring) structure, and is preferably a poly-ring (fused ring) structure. The atom of the 16th element in the e-ring is more preferably an oxygen atom or a sulfur atom. The ring structure of the e-ring is R in general formula (1-3). ４ and R ５ It is even more preferable that the ring structure, together with the aromatic ring to which it is bonded, constitutes a dibenzofuran ring or a dibenzothiophene ring, that is, a benzofuran ring or a benzothiophene ring structure. Also, R in general formula (1-3) ４ and R ５ Preferably, all of these are hydrogen atoms.

[0046] Specific examples of compounds represented by general formula (1-1) are shown below by their chemical formulas and in the examples described later. Of course, in this disclosure, compounds represented by general formula (1-1) are not limited to the following specific examples, as long as they fall within the definition of general formula (1-1).

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053] The content (ppm) of the compound represented by general formula (1-1) (first component) in the luminescent composition is preferably 1 ppm or more and 3,000 ppm or less, based on the total mass of the luminescent composition. Furthermore, the content (ppm) of the compound represented by general formula (1-1) (first component) in the luminescent composition is preferably 0.001 times or more and 0.20 times or less in mass ratio to the content (ppm) of the compound represented by general formula (2) (second component). By setting the mass ratio of the content of the first component to the content of the second component within the above range, energy transfer from the host material (second component) occurs efficiently, and aggregation of the emitter material (first component) can be further suppressed. As a result, the luminescence efficiency of the organic compound layer formed by the luminescent composition can be further increased.

[0054] (Second component) The luminescent composition contains a compound represented by the following general formula (2). The luminescent composition may contain one or more compounds represented by the following general formula (2).

[0055]

[0056] In general formula (2), R １１ ~R ２０ Each of these independently represents a hydrogen atom, or an alkyl group, aryl group, or heteroaryl group which may have a substituent. However, R １１ ~R ２０ At least one of these is a heteroaryl group containing an atom of a group 16 element, which may have substituents.

[0057] R １１ ~R ２０In at least one of these, the group 16 element atom in the heteroaryl group containing a group 16 element atom is preferably an oxygen atom or a sulfur atom, and more preferably an oxygen atom from the viewpoint of electronegativity. That is, R １１ ~R ２０ It is more preferable that at least one of them is a heteroaryl group containing an oxygen atom.

[0058] Furthermore, the heteroaryl group containing an atom of a Group 16 element is preferably a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, or a dibenzothiophenyl group, which may have substituents. Among these, a benzofuranyl group or a dibenzofuranyl group, which may have substituents, is more preferred. As substituents in these groups, an aryl group is preferred, a phenyl group is more preferred, and being unsubstituted is even more preferred.

[0059] In addition to the heteroaryl group containing the above-mentioned Group 16 element atoms, R １１ ~R ２０ Preferably, at least one of these is a triphenyl group (substituted or unsubstituted triphenyl group) or a quaterphenyl group (substituted or unsubstituted quaterphenyl group), which may have substituents. １１ ~R ２０ Compounds represented by general formula (2), in which at least one of the groups is a triphenyl group or a quaterphenyl group, have good solubility in organic solvents.

[0060] Specific examples of compounds represented by general formula (2) are shown below by their chemical formulas and in the examples described later. Of course, in this disclosure, compounds represented by general formula (2) are not limited to the following specific examples, as long as they are included in the definition of general formula (2).

[0061]

[0062]

[0063]

[0064] The content (ppm) of the compound represented by general formula (2) (second component) in the luminescent composition is preferably 100 ppm or more and 100,000 ppm or less (0.01% by mass or more and 10.0% by mass or less) based on the total mass of the luminescent composition.

[0065] (Third component) The luminescent composition contains an organic solvent. The organic solvent can be used to adjust various properties of the luminescent composition, such as the compatibility of various materials, the viscosity of the liquid, and the surface tension. The luminescent composition may contain one or more organic solvents.

[0066] The organic solvent is not particularly limited as long as it can dissolve the first and second components described above. Among these, organic solvents containing heteroatoms are preferred. By using a luminescent composition containing an organic solvent containing heteroatoms, it is expected that the uneven distribution of the first and second components during the drying process of the luminescent composition can be suppressed. Suitable heteroatoms in the organic solvent containing heteroatoms include nitrogen atoms, oxygen atoms, and halogen atoms such as chlorine atoms and bromine atoms. The organic solvent may contain one or more types of heteroatoms.

[0067] Furthermore, it is more preferable to use an organic solvent having a boiling point of 70°C to 300°C at 1 atmosphere. The organic solvent may be water-soluble or water-miscible. The content (by mass) of the organic solvent in the liquid luminescent composition is preferably 80.0% by mass or more and 99.9% by mass or less, based on the total mass of the luminescent composition.

[0068] Examples of organic solvents include aromatic hydrocarbon compounds, alkyl halides, ethers, ketones, esters, amide compounds, and cyclic amide compounds (lactams). It is preferable to use one or more of these.

[0069] Examples of aromatic hydrocarbon compounds include toluene (boiling point 111°C), o-xylene (boiling point 145°C), p-xylene (boiling point 138°C), mesitylene (boiling point 165°C), chlorobenzene (boiling point 132°C), o-dichlorobenzene (boiling point 179°C), anisole (boiling point 154°C), and cyclohexylbenzene (boiling point 236°C). Examples of alkyl halides include dichloromethane (boiling point 40°C) and chloroform (boiling point 61°C).

[0070] Examples of ethers include diethyl ether (boiling point 35°C), dibutyl ether (boiling point 141°C), tetrahydrofuran (boiling point 66°C), 2-methyltetrahydrofuran (boiling point 80°C), 1,4-dioxane (boiling point 101°C), and diethylene glycol dimethyl ether (boiling point 162°C).

[0071] Examples of ketones include cyclopentanone (boiling point 131°C), cyclohexanone (boiling point 156°C), and methyl ethyl ketone (boiling point 80°C). Examples of esters include ethyl acetate (boiling point 77°C), butyl acetate (boiling point 126°C), and methyl benzoate (boiling point 200°C).

[0072] Examples of amide compounds include dimethylformamide (boiling point 153°C) and dimethylacetamide (boiling point 165°C). Examples of cyclic amide compounds (lactams) include N-methylpyrrolidone (boiling point 202°C) and dimethylimidazolidinone (boiling point 225°C).

[0073] (Additives) In addition to the first, second, and third components described above, the luminescent composition may contain other additives as needed. Examples of other additives include charge transport materials, resins, plasticizers, antioxidants, and ultraviolet absorbers.

[0074] As described in detail above, the luminescent composition of this embodiment contains the compound represented by the general formula (1-1), the compound represented by the general formula (2), and an organic solvent, making it possible to form an organic compound layer with excellent color purity and luminescence efficiency. Therefore, the luminescent composition can be suitably used to form an organic compound layer in an organic light-emitting device.

[0075] <Organic Light-Emitting Device> An organic light-emitting device according to one embodiment of the present disclosure (hereinafter sometimes simply referred to as "organic light-emitting device") comprises a first electrode, a second electrode, and an organic compound layer disposed between the first electrode and the second electrode, wherein the organic compound layer contains a compound represented by the above-mentioned general formula (1-1) (first component) and a compound represented by the above-mentioned general formula (2) (second component).

[0076] An organic light-emitting element comprises at least a pair of electrodes, a first electrode and a second electrode, and an organic compound layer disposed between these electrodes. An example of an organic light-emitting element is one in which an insulating layer, the first electrode, the organic compound layer, and the second electrode are laminated on a substrate in this order. A protective layer and a color filter may be provided on the second electrode (in the direction opposite to the substrate). If a color filter is provided, a planarization layer may be provided between the protective layer and the color filter. One of the first electrode and the second electrode is the anode and the other is the cathode.

[0077] In the organic light-emitting element of this embodiment, the organic compound layer may be a single layer or a laminate having multiple layers, as long as it has a light-emitting layer. At least one of the constituent layers of the organic compound layer may contain the compound represented by the aforementioned general formula (1-1) (first component) and the compound represented by the aforementioned general formula (2) (second component). The organic compound layer containing the first and second components can be easily formed using the aforementioned light-emitting composition. Therefore, it is preferable that at least one of the constituent layers of the organic compound layer is a layer formed by the aforementioned light-emitting composition, and more specifically, it is more preferable that it is a layer formed by coating and drying the aforementioned light-emitting composition. From the viewpoint of luminescence efficiency, it is preferable that the constituent layer containing the aforementioned first and second components is a light-emitting layer. The members constituting the organic light-emitting element will be described in detail below.

[0078] (Substrate) Substrates made of materials such as quartz, glass, silicon, resin, and metal can be used. Switching elements such as transistors and components such as wiring can be placed on the substrate, and an insulating layer can be further provided on these components. The insulating layer is a layer made of a material that can form contact holes to ensure conductivity between the anode and the wiring, and can also ensure insulation from wiring that is not connected. Examples of materials for forming such an insulating layer include resins such as polyimide; silicon compounds such as silicon oxide and silicon nitride; and so on.

[0079] (Electrodes) A ​​pair of electrodes consists of a first electrode and a second electrode. Of the first and second electrodes, one is the anode and the other is the cathode. When a voltage is applied in the direction in which the organic light-emitting element emits light, the electrode with the higher potential becomes the anode and the other becomes the cathode. In other words, the electrode that supplies holes to the light-emitting layer is the anode, and the electrode that supplies electrons is the cathode. Each electrode may be made of one type of material, or it may be made of two or more types of materials. Furthermore, each electrode may be a single layer, or it may be a laminate of two or more layers stacked together.

[0080] The anode is preferably formed from a material with a high work function. Examples of such materials include metals, metal oxides, mixtures and alloys thereof, and conductive polymers. Examples of metals include gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium, and tungsten. Examples of metal oxides include tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide. Examples of conductive polymers include polyaniline, polypyrrole, and polythiophene.

[0081] When used as a reflective electrode, the material used to form the anode can be a metal such as chromium, aluminum, silver, titanium, tungsten, and molybdenum; or an alloy or laminate thereof. When used as a transparent electrode, the material used to form the anode can be a metal oxide such as indium tin oxide (ITO) or indium zinc oxide. Photolithography can be used to form the anode.

[0082] The cathode is preferably formed from a material with a low work function. Examples of such materials include alkali metals such as lithium; alkaline earth metals such as calcium; other metals such as aluminum, titanium, manganese, silver, lead, and chromium; oxides, mixtures, and alloys thereof. Examples of alloys include magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper, and zinc-silver. Examples of metal oxides include indium tin oxide (ITO). Among these, silver and silver alloys are preferred as the material for forming the cathode, and silver alloys are even more preferred in order to suppress silver aggregation. The ratio of silver to other metals in the silver alloy does not matter as long as silver aggregation can be suppressed. For example, silver:other metals = 1:1 (mass ratio) may be appropriate.

[0083] The cathode may be formed from a metal oxide such as indium tin oxide (ITO) to make the organic light-emitting element a top-emission element, or the reflective electrode may be formed from a metal such as aluminum (Al) to make the organic light-emitting element a bottom-emission element. When forming the cathode, photolithography or sputtering can be used. Among these, it is preferable to form the cathode by sputtering (DC or AC). The cathode (film) formed by sputtering has excellent coverage and can reduce resistance.

[0084] (Protective Layer) A protective layer can be provided on the cathode (second electrode). For example, by bonding a glass with a desiccant layer onto the cathode to form a protective layer, the intrusion of water and other substances into the organic compound layer can be suppressed, thereby suppressing the occurrence of display defects. Alternatively, by providing a passivation film such as silicon nitride as a protective layer on the cathode, the intrusion of water and other substances into the organic compound layer can be suppressed. The protective layer can be formed by chemical vapor deposition (CVD). Alternatively, after film formation by chemical vapor deposition, a two-layer protective layer may be provided by atomic deposition (ALD). For example, after the formation of the cathode, it can be transported to another chamber while maintaining a vacuum, and a silicon nitride film can be formed as a protective layer by CVD. The average thickness of the protective layer is preferably 1 μm or more and 10 μm or less.

[0085] (Color Filter) A color filter can be provided on the protective layer. For example, a color filter corresponding to the size of the organic light-emitting element may be provided on a separate substrate and bonded to the substrate on which the organic light-emitting element is provided, or the color filter may be patterned using photolithography technology. The color filter can be formed from polymer materials or the like.

[0086] (Planarization layer) A planarization layer can be provided between the protective layer and the color filter. Examples of constituent materials for the planarization layer include organic compounds. In particular, it is preferable to form the planarization layer with a polymer organic compound such as a resin. The planarization layer may be provided on the top and bottom (both sides) of the color filter, and the constituent materials of the planarization layer may be the same or different. Examples of constituent materials for the planarization layer include resins such as polyvinylcarbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenolic resin, epoxy resin, silicone resin, and urea resin. One of these resins may be used alone, or two or more may be used in combination.

[0087] (Opposite Substrate) An opposite substrate can be provided on the planarization layer. Since the opposite substrate is provided opposite to the aforementioned substrate, it is referred to as the opposite substrate in this disclosure. The material for forming the opposite substrate is the same as the material for forming the substrate.

[0088] (Organic compound layer) The organic compound layer includes at least a light-emitting layer positioned between the first electrode and the second electrode, which are a pair of electrodes. As described above, the organic compound layer may be a single layer or a laminate having multiple layers, as long as it has a light-emitting layer.

[0089] When the organic compound layer is a laminate having multiple layers, at least one of the organic compound layers is an emissive layer. The organic compound layer may also have layers other than the emissive layer. Examples of layers other than the emissive layer include hole injection layers, hole transport layers, electron blocking layers, hole-exciton blocking layers, electron transport layers, and electron injection layers. Hole transport layers and electron transport layers are also called charge transport layers. The emissive layer may be a single layer or a laminate of two or more layers.

[0090] The first electrode, the light-emitting layer, and the transport layer that may be placed between them all have the function of transporting charge together, and therefore, these layers can be treated collectively as the first charge transport layer. Similarly, the second electrode, the light-emitting layer, and the transport layer placed between them all have the function of transporting charge together, and therefore, these layers can be treated collectively as the second charge transport layer. Accordingly, one surface of the light-emitting layer may be in contact with the first charge transport layer, while the other surface may be in contact with the second charge transport layer.

[0091] Preferably, the average film thickness of each layer constituting the organic compound layer is independently between 1 nm and 1,000 nm (1 μm or less). In particular, from the viewpoint of further improving the luminescence characteristics, it is even more preferable that the average film thickness of each layer constituting the organic compound layer is independently between 10 nm and 200 nm.

[0092] In this disclosure, the average thickness of each layer (film) is the average of the thicknesses of any five points measured using a stylus step meter. As the stylus step meter, commercially available devices such as the product name "P-16+" (manufactured by KLA-Tencor) can be used.

[0093] <Method for Manufacturing an Organic Light-Emitting Device> One embodiment of the method for manufacturing an organic light-emitting device is a method for manufacturing an organic light-emitting device comprising an organic compound layer. This manufacturing method includes the step of coating the aforementioned luminescent composition by a coating method or a printing method, drying it, and forming an organic compound layer.

[0094] In this process, the aforementioned luminescent composition is applied to predetermined locations by a coating or printing method and dried, forming an organic compound layer such as a luminescent layer by a so-called wet process. The coating method is preferably spin coating, casting, gravure coating, bar coating, roll coating, wire bar coating, dip coating, spray coating, capillary coating, or spray coating. The printing method is preferably screen printing, flexographic printing, offset printing, or inkjet printing. Among these, spray coating and inkjet printing are more preferred, and inkjet printing is even more preferred. By employing these methods, larger-area organic light-emitting elements can be easily manufactured.

[0095] The organic compound layer of the organic light-emitting element manufactured by this manufacturing method may be a single layer or a laminate having multiple layers, as long as it has a light-emitting layer. Therefore, in this manufacturing method, at least one of the constituent layers of the organic compound layer may be formed by the above process, and the other constituent layers may be formed by a wet process, similar to the above process, or by a dry process. As a wet process, a liquid composition containing the constituent materials of the organic compound layer and a liquid medium may be applied to the target area by the above coating method or printing method. As a dry process, examples include vacuum deposition, ionization deposition, sputtering, and plasma methods. Among these, vacuum deposition, ionization deposition, spray coating, and inkjet methods are preferred. These methods are suitable from the viewpoint of being able to manufacture large-area organic light-emitting elements. In particular, the inkjet method is preferred.

[0096] It is preferable to coat the luminescent composition by a wet process and then dry it to remove the organic solvent in the luminescent composition by volatilization or other means. The drying conditions can be appropriately set according to the constituent materials such as the organic compound layer. It is preferable to dry in an air or inert gas (nitrogen, argon, etc.) atmosphere. The heating temperature for drying is preferably 100°C to 250°C, and more preferably 110°C to 200°C. The heating time for drying is preferably 5 minutes to 60 minutes. The pressure during heating for drying may be at normal pressure (1 atmosphere) or under reduced pressure (100 Pa to 0.1 MPa). The various conditions in the drying process (temperature, pressure, and time) should be set so that the organic solvent can be removed from the organic compound layer, etc.

[0097] When forming an organic compound layer by a wet process using a luminescent composition or the above-mentioned liquid composition (hereinafter sometimes simply referred to as "composition"), it is preferable to appropriately determine the composition. The content (mass%) of organic solvent in the composition is preferably 5.0 to 100.0 times the total mass ratio of the content (mass%) of solid components constituting the organic compound layer.

[0098] When applying a composition to a substrate using an inkjet method to form an organic compound layer, it is preferable to appropriately control its physical properties. The surface tension of the composition at 25°C is preferably 15 mN / m to 75 mN / m, and more preferably 25 mN / m to 45 mN / m. The surface tension of the composition can be adjusted by appropriately determining the type and content of the liquid medium, such as an organic solvent, in the composition. Furthermore, the viscosity of the composition at 25°C is preferably 0.1 mPa·s to 20.0 mPa·s, and more preferably 0.5 mPa·s to 10.0 mPa·s. By setting the viscosity within the above range, clogging and ejection failures in the liquid ejection head when ejecting using an inkjet method can be suppressed.

[0099] <Pixel Circuit> The aforementioned organic light-emitting element can be used in an organic light-emitting device. The organic light-emitting device may have a pixel circuit connected to the organic light-emitting element. The pixel circuit is preferably an active-matrix type that independently controls the emission of light from multiple organic light-emitting elements. The active-matrix circuit may be voltage-programmed or current-programmed. The drive circuit has a pixel circuit for each pixel. The pixel circuit may further include a transistor for controlling the emission brightness of the organic light-emitting element, a transistor for controlling the emission timing, and a transistor for connecting to ground without going through the organic light-emitting element.

[0100] The organic light-emitting device has a display area and a peripheral area arranged around the display area. The display area has a pixel circuit, and the peripheral area has a display control circuit. The mobility of the transistors constituting the pixel circuit may be smaller than the mobility of the transistors constituting the display control circuit. The slope of the current-voltage characteristic of the transistors constituting the pixel circuit may be smaller than the slope of the current-voltage characteristic of the transistors constituting the display control circuit. The slope of the current-voltage characteristic can be measured by the so-called Vg-Ig characteristic. The transistors constituting the pixel circuit are transistors connected to the organic light-emitting element.

[0101] <Pixels> The organic light-emitting device has multiple pixels. Each of the multiple pixels has sub-pixels that emit light of a different color from the others. Each sub-pixel independently has a light-emitting color of red (R), green (G), and blue (B). The pixels emit light from a region also called the pixel aperture. The pixel aperture is preferably 15 μm or less, and preferably 5 μm or more. The pixel aperture can be, for example, 11.0 μm, 9.5 μm, 7.4 μm, 6.4 μm, etc. The distance between sub-pixels is preferably 10 μm or less. The distance between sub-pixels can be, for example, 8.0 μm, 7.4 μm, 6.4 μm, etc.

[0102] Pixels can take on known arrangements in a plan view. For example, they may be in a stripe arrangement, delta arrangement, pentile arrangement, or Bayer arrangement. The shape of subpixels in a plan view may be any known shape. For example, rectangles, rhombuses or other quadrilaterals, hexagons, etc. These shapes are not exact figures, but are included in rectangles as long as they are close to a rectangle. The shape of subpixels and the pixel arrangement can be used in combination.

[0103] <Applications of Organic Light-Emitting Devices> The organic light-emitting device of this embodiment can be used as a component of display devices and lighting devices. Other applications include exposure light sources for electrophotographic image recording devices, backlights for liquid crystal display devices, and light-emitting devices with a color filter in a white light source.

[0104] [Display Device] A display device according to one embodiment of the present disclosure is a device comprising a plurality of pixels, at least one of which comprises the aforementioned organic light-emitting element and a transistor connected to the organic light-emitting element. The display device will be described below with reference to specific configuration examples of the display device of this embodiment.

[0105] The display device includes an image input unit that receives image information from, for example, an area CCD, a linear CCD, and a memory card, and an information processing unit that processes the received image information. The CCD is a charge-coupled element. The display device may also be an image information processing device that displays the received image information on a display unit. Furthermore, the display unit of an imaging device or an inkjet recording device may have a touch panel function. Specific examples of driving methods for the touch panel function include infrared, capacitive, resistive, and electromagnetic induction methods. The display device may also be used in the display unit of a so-called hybrid recording device.

[0106] Next, the details of the display device of this embodiment will be described with reference to the drawings. Figure 1A is a schematic cross-sectional view showing an example of pixels constituting the display device of this embodiment.

[0107] The pixels shown in Figure 1A include sub-pixels 10R, 10G, and 10B. The sub-pixels 10R, 10G, and 10B are distinguished by their emission color. The emission color may be distinguished and determined by the wavelength of light emitted from the light-emitting layer, or it may be determined by selective transmission or color conversion of the light emitted from the sub-pixels 10R, 10G, and 10B by color filters 7R, 7G, and 7B. Each of the sub-pixels 10R, 10G, and 10B comprises an interlayer insulating layer 1, a reflective electrode 2 which is a first electrode provided on the interlayer insulating layer 1, an insulating layer 3 covering the end of the reflective electrode 2, and an organic compound layer 4 (which may also be called an organic semiconductor layer 4) covering the first electrode and the insulating layer. Each of the sub-pixels 10R, 10G, and 10B further comprises a transparent electrode 5, a protective layer 6, and color filters 7R, 7G, and 7B, respectively.

[0108] Transistors and capacitive elements may be arranged in the layer below or inside the interlayer insulating layer 1. The transistors and the first electrode may be electrically connected via contact holes (not shown) or the like. The insulating layer 3 is also called a bank or pixel separation layer. The insulating layer 3 covers the end of the first electrode (reflecting electrode 2) and is arranged to surround the first electrode. The portion of the first electrode not covered by the insulating layer 3 is in contact with the organic compound layer 4 and becomes a light-emitting region. The organic compound layer 4 has 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. The second electrode may be a transparent electrode, a reflective electrode, or a semi-transparent electrode. The protective layer 6 is a layer for reducing the penetration of liquid components such as water into the organic compound layer. The protective layer may consist of multiple layers. If the protective layer consists of multiple layers, the multiple layers may include inorganic compound layers and organic compound layers.

[0109] The color filters 7R, 7G, and 7B are distinguished according to color. The color filters may be formed on a planarization film (not shown). Alternatively, a resin protective layer (not shown) may be placed on the color filters. Furthermore, the color filters may be formed on the protective layer 6, or they may be bonded to an opposing substrate such as a glass substrate after being provided on it.

[0110] Figure 1B is a schematic cross-sectional view showing one embodiment of the display device of the present disclosure. The display device 100 shown in Figure 1B comprises an organic light-emitting element 26 and an active element 18 such as a thin-film transistor (TFT) connected to the organic light-emitting element 26. A transistor such as a TFT is an example of an active element. The display device 100 comprises a substrate 11 formed of a material such as glass or silicon, and an insulating layer 12 provided on the substrate 11. The active element 18 such as a TFT is arranged on the insulating layer 12. The active element 18 comprises a gate electrode 13, a gate insulating film 14, a semiconductor layer 15, a drain electrode 16, and a source electrode 17. An insulating film 19 is provided on the upper part of the active element 18. The anode 21 and the source electrode 17 constituting the organic light-emitting element 26 are connected via a contact hole 20 provided in the insulating film 19. Note that the method of electrical connection between the electrodes (anode, cathode) included in the organic light-emitting element and the electrodes (source electrode, drain electrode) included in the active element is not limited to the embodiment shown in Figure 1B. In other words, it is sufficient that the anode or cathode is electrically connected to the TFT source electrode or drain electrode.

[0111] In the display device 100 shown in Figure 1B, a single-layer organic compound layer 22 (which may also be called an organic semiconductor layer 22) is shown, but the organic compound layer may include multiple layers. A first protective layer 24 and a second protective layer 25 are provided on the cathode 23 to reduce the degradation of the organic light-emitting element 26. As the active element 18 constituting the display device 100, for example, a transistor using a single-crystal silicon wafer or a thin-film transistor having an active layer on an insulating surface of a substrate can be used. Examples of the active layer include non-single-crystal silicon such as single-crystal silicon, amorphous silicon, and microcrystalline silicon, and non-single-crystal oxide semiconductors such as indium zinc oxide and indium gallium zinc oxide.

[0112] Active elements such as transistors that constitute a display device may be formed within a substrate such as a silicon substrate. "Formed within a substrate" means that the transistors are formed by processing the substrate, such as a silicon substrate. In other words, the substrate and the transistors may be formed integrally.

[0113] The luminescence of an organic light-emitting element is controlled by a TFT, which is an example of an active element (switching element). By arranging multiple organic light-emitting elements in a plane, an image can be displayed by adjusting the luminescence of each of the multiple organic light-emitting elements. In addition to TFTs, the switching element may also be a transistor formed from low-temperature polysilicon or an active matrix driver formed on a substrate such as a silicon substrate. If the size of the display area is, for example, about 0.5 inches, it is preferable to arrange the organic light-emitting elements on a silicon substrate.

[0114] Figure 2 is a schematic diagram showing another embodiment of the display device of the present disclosure. The display device 1000 shown in Figure 2 comprises an upper cover 1001 and a lower cover 1009 arranged opposite each other. Furthermore, the display device 1000 comprises a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008, which are arranged between the upper cover 1001 and the lower cover 1009. 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. When the display device is a portable device, a battery 1008 is usually provided. The battery 1008 may be provided in a different location.

[0115] The display device may have red (R), green (G), and blue (B) color filters. The red, green, and blue color filters may be arranged in a delta array, a stripe array, or a mosaic array. The display device can be used in the display unit of a mobile terminal. When the display device is used in the display unit of a mobile terminal, the display device may have both display and operation functions. Examples of mobile terminals include smartphones and other mobile phones, tablets, and head-mounted displays.

[0116] The display device can be used in the display unit of an imaging device that comprises an optical unit having multiple lenses and an image sensor that receives light passing through the optical unit. The imaging device may also have a display unit that displays information acquired by the image sensor. The display unit may be positioned outside the imaging device or positioned inside the viewfinder. Examples of imaging devices include digital cameras and digital video cameras. The imaging device can also be called a photoelectric converter.

[0117] [Imaging Device] An imaging device according to one embodiment of the present disclosure comprises an optical unit having a plurality of lenses, an image sensor that receives light passing through the optical unit, and a display unit that displays an image captured by the image sensor. The display unit includes the aforementioned organic light-emitting element. The imaging device will be described below with reference to specific configuration examples of the imaging device of this embodiment.

[0118] Figure 3A is a schematic diagram showing an example of an imaging device. The imaging device 1100 shown in Figure 3A comprises a viewfinder 1101, a rear display 1102, an operating unit 1103, and a housing 1104. A display device can be used as the viewfinder 1101. The display device may display not only the image to be captured, but also environmental information and imaging instructions. Examples of environmental information include the intensity of ambient light, the direction of ambient light, the speed at which the subject is moving, and the possibility of the subject being obscured by an obstruction.

[0119] Since the optimal timing for imaging is only a short time, it is preferable to be able to display information quickly. Organic light-emitting elements can be suitably applied to display devices because of their fast response speed. The imaging device 1100 has an optical section (not shown). The optical section has multiple lenses and forms an image on the image sensor housed in the housing 1104. The focus of the multiple lenses can be adjusted by controlling their relative positions. The relative positions of the multiple lenses can also be controlled by automatic operation.

[0120] [Electronic Devices] An electronic device according to one embodiment of the present disclosure comprises a display unit, a housing on which the display unit is provided, and a communication unit provided in the housing for communicating with the outside. The display unit includes the aforementioned organic light-emitting element. Hereinafter, an example of a portable device will be given as a specific example of the configuration of the electronic device according to this embodiment, and the electronic device will be described.

[0121] Figure 3B is a schematic diagram showing an example of a portable device. The portable device 1200 shown in Figure 3B comprises a display unit 1201, an operation unit 1202, and a housing 1203. An organic light-emitting element can be used for the display unit 1201. The housing 1203 comprises a circuit, a printed circuit board having the circuit, a battery, and a communication unit. The operation unit 1202 may be a button or a touch panel type response unit. The operation unit 1202 may also be a biometric recognition unit that recognizes fingerprints to unlock the device. A portable device further comprising a communication unit can also be called a communication device. The portable device 1200 may further be equipped with a lens and an image sensor to give it a camera function. Images captured by the camera function are displayed on the display unit 1201. Examples of portable devices 1200 include smartphones and laptop computers.

[0122] Figure 4A is a schematic diagram showing another embodiment of the display device of the present disclosure. The display device 1300 shown in Figure 4A is a monitor such as a television or personal computer. The display device 1300 comprises a frame 1301, a display unit 1302, and a base 1303 that supports the display unit 1302. An organic light-emitting element can be used for the display unit 1302. The form of the base 1303 is not limited to the form shown in Figure 4A, and the lower edge of the frame 1301 may also serve as the base. Furthermore, the frame 1301 and the display unit 1302 may be curved. If the frame 1301 and the display unit 1302 are curved, their radii of curvature are preferably 5,000 mm or more and 6,000 mm or less.

[0123] Figure 4B is a schematic diagram showing another embodiment of the display device of the present disclosure. The display device 1310 shown in Figure 4B is a so-called foldable display device configured to be bendable. The display device 1310 comprises a first display unit 1311, a second display unit 1312, a housing 1313, and a bending point 1314. Organic light-emitting elements can be used for the first display unit 1311 and the second display unit 1312. The first display unit 1311 and the second display unit 1312 may be a single display unit without a seam. The first display unit 1311 and the second display unit 1312 can be separated at the bending point 1314. The first display unit 1311 and the second display unit 1312 may each display different images, or they may display a single image.

[0124] [Lighting Device] A lighting device according to one embodiment of the present disclosure comprises a light source and a member that transmits light emitted by the light source, wherein the light source includes the organic light-emitting element described above. The lighting device will be described below with reference to specific configuration examples of the lighting device of this embodiment.

[0125] Figure 5A is a schematic diagram showing an example of a lighting device. The lighting device 1400 shown in Figure 5A comprises a housing 1401, a light source 1402, a circuit board 1403, an optical filter 1404, and a light diffusion unit 1405. An organic light-emitting element can be used as the light source 1402. The optical filter 1404 may be a filter that improves the color rendering of the light source. The light diffusion unit 1405 can effectively diffuse the light from the light source, such as for lighting up, and deliver light over a wide area. The optical filter 1404 and the light diffusion unit 1405 may be provided on the light-emitting side of the lighting. A cover may be provided on the outermost part as needed.

[0126] A lighting device is, for example, a device for illuminating a room, and comprises a light source and a component that transmits the light emitted by the light source. The lighting device may emit light in any color from blue to red, not just white or daylight white. "White" refers to a color with a color temperature of about 4,200K, and "daylight white" refers to a color with a color temperature of about 5,000K. The lighting device may further include a dimming circuit to adjust the light. The lighting device may further include a power supply circuit connected to an organic light-emitting element used as a light source. The power supply circuit is a circuit that converts AC voltage to DC voltage. The lighting device may further include a light diffuser or a color filter as a component that transmits the light emitted by the light source. The lighting device may also further include a heat dissipation section that releases heat from inside the device to the outside. Examples of materials that make up the heat dissipation section include metals with high specific heat and liquid silicon.

[0127] [Mobile Body] A mobile body according to one embodiment of the present disclosure comprises a body and a light fixture provided on the body, wherein the light fixture includes the aforementioned organic light-emitting element. Hereinafter, the mobile body will be described using an example of an automobile as a specific configuration example of the mobile body of this embodiment.

[0128] Figure 5B is a schematic diagram showing an example of a mobile body. The mobile body shown in Figure 5B is an automobile 1500 equipped with lighting fixtures such as taillights 1501 that illuminate when the brakes are applied. Organic light-emitting elements can be used in the taillights 1501. The taillights 1501 may be equipped with a protective member to protect the organic light-emitting elements. The protective member can be made of a transparent material with a certain degree of strength. Examples of such materials include resin materials such as polycarbonate. Resin materials such as polycarbonate may contain franciocarboxylic acid derivatives or acrylonitrile derivatives.

[0129] The automobile 1500 may further include a body 1503 and windows 1502 provided in the body 1503. The windows 1502 may be transparent displays using organic light-emitting elements, unless they are for checking the front and rear of the automobile 1500. Components such as electrodes that constitute the transparent display using organic light-emitting elements are made of transparent materials.

[0130] Examples of mobile bodies other than the automobile 1500 shown in Figure 5B include ships, aircraft, and drones. The mobile body may be equipped with a body and a light fixture mounted on the body that emits light to indicate the body's position. Organic light-emitting elements can be used for the light fixture.

[0131] The display device can be applied to imaging display devices such as smart glasses, head-mounted displays, and smart contact lenses, which are wearable devices. Such an imaging display device comprises, for example, a photoelectrically convertible imaging device that converts visible light into electrical signals, and a display device that emits visible light.

[0132] Figure 6A is a schematic diagram showing an example of a wearable device. An imaging device 1602, such as a CMOS sensor or a SPAD sensor, is provided on the front surface of the lens 1601 of the smart glasses 1600 (eyeglasses) shown in Figure 6A. A CMOS (Complementary Metal-Oxide-Semiconductor) sensor is a solid-state image sensor using complementary metal-oxide-semiconductor. A SPAD (Single Photon Avalanche Diode) sensor is a sensor that has an electronic element that outputs a single large electrical pulse signal through avalanche-like multiplication when a single photon is incident on the pixel. A display device is provided on the back surface of the lens 1601. The smart glasses 1600 further includes a control device 1603. The control device 1603 functions as a power supply that provides power to the imaging device 1602 and the display device, and also controls the operation of the imaging device 1602 and the display device. The lens 1601 has an optical system formed therein for focusing light onto the imaging device 1602.

[0133] Figure 6B is a schematic diagram showing another example of a wearable device. The smart glasses 1610 (eyeglasses) shown in Figure 6B include a control device 1612. The control device 1612 is equipped with an imaging device corresponding to the imaging device 1602 (Figure 6A) and a display device. The lens 1611 has an optical system formed therein for projecting light emitted from the imaging device and display device within the control device 1612, and an image is projected. The control device 1612 functions as a power supply to supply power to the imaging device and display device, and also controls the operation of the imaging device and display device. The control device may have a gaze detection unit that detects the wearer's gaze. Infrared light can be used for gaze detection. The infrared light emitter emits infrared light towards the eyeball of the user who is gazing at the displayed image. The imaging unit, which has a photodetector, detects the reflected light from the eyeball of the emitted infrared light, thereby obtaining an image of the eyeball. By having a reduction means that reduces the light from the infrared light emitter to the display unit in a planar view, the deterioration of image quality can be reduced.

[0134] The smart glasses 1610 detect the user's gaze toward the displayed image from an image of the eyeball obtained by imaging with infrared light. Any known method can be applied to gaze detection using the image of the eyeball. As an example, a gaze detection method based on the Purkinje image obtained by the reflection of the irradiated light from the cornea can be used. Specifically, gaze detection processing based on the pupil-corneal reflection method is performed. Using the pupil-corneal reflection method, the user's gaze is detected by calculating a gaze vector representing the orientation (rotation angle) of the eyeball based on the pupil image and the Purkinje image included in the image of the eyeball.

[0135] The display device may have an imaging device with a light-receiving element, and may control the display image of the display device based on the user's gaze information from the imaging device. Specifically, based on the gaze information, a first field of view area that the user is fixated on and a second field of view area other than the first field of view area are determined. The first and second field of view areas may be determined by the control device of the display device, or they may be determined by an external control device and received. In the display area of ​​the display device, the display resolution of the first field of view area may be controlled to be higher than the display resolution of the second field of view area. That is, the resolution of the second field of view area may be lower than that of the first field of view area.

[0136] Furthermore, the display area has a first display area and a second display area different from the first display area, and based on line-of-sight information, the area with higher priority is determined from the first display area and the second display area. The first and second field-of-sight areas may be determined by the control device of the display device, or they may be determined by an external control device and received. The resolution of the high-priority area may be controlled to be higher than the resolution of the areas other than the high-priority area. In other words, the resolution of areas with relatively lower priority may be lower.

[0137] Artificial intelligence (AI) may be used to determine the first field of view area and high-priority areas. The AI ​​may be a model configured to estimate the angle of gaze and the distance to the target object at the end of the line of sight from the image of the eye, using the image of the eye and the direction the eye was actually looking in the image as training data. The AI ​​program may be installed in a display device, an imaging device, or an external device. If the AI ​​program is installed in an external device, information is transmitted to the display device via communication. When display control is performed based on visual detection, it can preferably be applied to smart glasses that further have an imaging device for capturing images of the outside. The smart glasses can display the captured external information in real time.

[0138] As described above, by using the device equipped with the aforementioned organic light-emitting element, it becomes possible to display information stably for extended periods with good image quality. Furthermore, the high efficiency and high brightness of the light output enable both good visibility outdoors and power-saving display.

[0139] The present disclosure will be described in more detail below with reference to examples and comparative examples, but the present disclosure is not limited in any way by the following examples unless it exceeds the gist of the disclosure.

[0140] <Preparation of Materials> (First Component) As the first component, compounds represented by the following chemical formulas D-01 to D-07 (referred to as compounds D-01 to D-07, respectively) were prepared. Compounds D-01 to D-04 are compounds represented by the general formula (1-1) mentioned above, and compounds D-05 to D-07 are compounds for comparison with the compound represented by the general formula (1-1).

[0141]

[0142]

[0143]

[0144]

[0145] (Second Component) As the second component, compounds represented by the following chemical formulas H-01 to H-17 (referred to as compounds H-01 to H-17, respectively) were prepared. Compounds H-01 to H-14 are compounds represented by the general formula (2) mentioned above, and compounds H-15 to H-17 are compounds for comparison with the compound represented by general formula (2).

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153] (Third component) Anisole (boiling point 154°C) was prepared as an organic solvent containing a heteroatom oxygen atom, and toluene (boiling point 111°C) was prepared as an organic solvent that does not contain a heteroatom.

[0154] <Preparation of Luminescent Compositions> (Examples 1-25 and Comparative Examples 1-7) The first, second, and third components listed in Table 1 were mixed in a mass ratio of 45:1455:98500 and dissolved by stirring at 70°C for 1 hour. Then, each luminescent composition was prepared by filtering through a filter with a pore size of 0.2 μm. Each luminescent composition contained 450 ppm of the first component, 14550 ppm of the second component, and 98.5% by mass of the third component, relative to the total mass of the luminescent composition.

[0155]

[0156] <Manufacturing of Organic Light-Emitting Devices> An ITO film was deposited on a glass substrate by sputtering to form an anode with a thickness of 100 nm, thereby obtaining a transparent conductive support substrate (ITO substrate). A hole injection layer forming composition was prepared by dispersing PEDOT:PSS (trade name "Clevios P ​​VP AI 4083", manufactured by Heraeus) in water, with a PEDOT:PSS concentration of 1.00% by mass. PEDOT:PSS is a composite of PEDOT (poly(3,4-ethylenedioxythiophene)) and PSS (polystyrene sulfonic acid), and is a type of conductive polymer. The prepared hole injection layer forming composition was spin-coated onto the UV-ozone treated ITO substrate, and then dried at 200°C for 30 minutes to form a hole injection layer with an average thickness of 30 nm.

[0157] The prepared luminescent composition was spin-coated onto the hole-injection layer described above, and then dried at 110°C for 15 minutes to form a luminescent layer with an average thickness of 40 nm, thereby obtaining a film sample. The obtained film sample was placed in a vacuum deposition machine, and an electron transport layer (TPBi) with an average thickness of 55 nm, an electron injection layer (LiF) with an average thickness of 0.5 nm, and a cathode (aluminum) with an average thickness of 100 nm were continuously formed by deposition. Next, a protective glass plate was placed over the sample in a dry nitrogen atmosphere, and then it was sealed with an acrylic resin adhesive to obtain an organic light-emitting element. For the luminescent composition described above, the luminescent compositions of Examples 1 to 25 and Comparative Examples 1 to 7, prepared using the materials shown in Table 1 above, were used to manufacture organic light-emitting elements corresponding to Examples 1 to 25 and Comparative Examples 1 to 7, respectively.

[0158] <Evaluation> The manufactured organic light-emitting devices were evaluated as follows. In this embodiment, "A," "B," and "C" were considered acceptable levels, and "D" was considered an unacceptable level in the evaluation criteria for each item shown below. The evaluation results are shown in Table 2.

[0159] (External quantum efficiency, color purity) The external quantum efficiency and color purity of the manufactured organic light-emitting element were measured using a spectroradiometer (product name "SR-LEDW-5N", manufactured by Topcon Techno House) and a DC voltage / current source (product name "6253", manufactured by ADC) at a current density of 10 mA / cm². ２ Measurements were taken under the specified conditions. Then, the external quantum efficiency and color purity were evaluated according to the evaluation criteria shown below. A higher external quantum efficiency indicates higher luminescence efficiency. As for color purity, the full width at half maximum (FWHM) of the EL (emission) spectrum (the spectral width at an intensity of 0.5, with the maximum emission intensity set to 1.0) was measured, and a narrower FWHM indicates higher color purity.

[0160] [External Quantum Efficiency] A: The external quantum efficiency was 1.20 times or more than that of Comparative Example 1. B: The external quantum efficiency was 1.10 times or more but less than 1.20 times that of Comparative Example 1. C: The external quantum efficiency was 1.05 times or more but less than 1.10 times that of Comparative Example 1. D: The external quantum efficiency was less than 1.05 times that of Comparative Example 1.

[0161] [Color Purity] A: The full width at half maximum of the EL spectrum was less than 35 nm. D: The full width at half maximum of the EL spectrum was 35 nm or more.

[0162]

[0163] Based on the above, it has been confirmed that the organic light-emitting element having a light-emitting layer formed by the light-emitting composition according to this embodiment exhibits excellent luminescence efficiency (external quantum efficiency) and color purity.

[0164] This disclosure is not limited to the embodiments described above, and various modifications and alterations are possible without departing from the spirit and scope of this disclosure. Accordingly, the following claims are attached to make the scope of this disclosure public.

[0165] This application claims priority based on Japanese Patent Application No. 2024-191492, filed on 31 October 2024, and Japanese Patent Application No. 2025-172949, filed on 14 October 2025, and all of the contents of those applications are incorporated herein by reference.

Claims

1. A light-emitting composition comprising a compound represented by the following general formula (1-1), a compound represented by the following general formula (2), and an organic solvent. (In the general formula (1-1), ring a and ring b each independently represent an aryl ring or a heteroaryl ring, and at least one hydrogen atom in these rings may be a deuterium atom, a halogen atom, a cyano group, or an alkyl group, an aryl group, a heteroaryl group, an amino group, an alkoxy group, an aryloxy group, a heteroaryloxy group, or a silyl group which may have a substituent. X １１ , ２０ , ２０ and X ２ each independently represent an oxygen atom, a sulfur atom, or N-R ６ . R ６ represents an aryl group, a heteroaryl group, or an alkyl group which may have a substituent, and may be bonded to ring a in the case of X １ and to ring b in the case of X ２ through a linking group or a single bond. R １ to R ３ each independently represent a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, or an alkyl group, an aryl group, a heteroaryl group, or a group represented by the general formula (1-2) which may have a substituent. However, at least one of R １ to R ３ represents a group represented by the general formula (1-2). In the general formula (1-2), ring c represents a heteroaryl ring containing an atom of Group 16 elements, X ３ represents an oxygen atom or a sulfur atom, and * represents the bonding position with the general formula (1-1).) (In the general formula (2), R １１ to R ２０ each independently represent a hydrogen atom or an alkyl group, an aryl group, or a heteroaryl group which may have a substituent. However, at least one of R １１ to R ２０ is a heteroaryl group containing an atom of Group 16 elements which may have a substituent.) 2. In the above general formula (2), R １１ ~R ２０ The luminescent composition according to claim 1, wherein at least one of the members is a heteroaryl group containing an oxygen atom.

3. The luminescent composition according to claim 1 or 2, wherein the organic solvent comprises an organic solvent containing a heteroatom.

4. In the above general formula (2), R １１ ~R ２０ The luminescent composition according to any one of claims 1 to 3, wherein at least one of the members is a triphenyl group or a quaterphenyl group which may have a substituent.

5. The luminescent composition according to any one of claims 1 to 4, wherein the compound represented by the general formula (1-1) comprises a compound represented by the following general formula (1-3). (In the above general formula (1-3), the d ring represents an aryl ring or heteroaryl ring which may have substituents, and the e ring represents a heteroaryl ring containing an atom of a group 16 element. ４ and R ５ Each of these independently represents a hydrogen atom, a deuterium atom, or an alkyl group, aryl group, or heteroaryl group which may have a substituent. ２ represents an oxygen atom or a sulfur atom. a ring, and R １ ~R ３ These terms are all equivalent to those in the general formula (1-1) above.

6. A method for manufacturing an organic light-emitting element comprising an organic compound layer, characterized by comprising the step of coating the luminescent composition described in any one of claims 1 to 5 by a coating method or a printing method and drying to form the organic compound layer.

7. The method for manufacturing an organic light-emitting element according to claim 6, wherein the coating method is a spin coating method, a cast method, a gravure coating method, a bar coating method, a roll coating method, a wire bar coating method, a dip coating method, a spray coating method, a capillary coating method, or a spray coating method.

8. The method for manufacturing an organic light-emitting element according to claim 6, wherein the printing method is a screen printing method, a flexographic printing method, an offset printing method, or an inkjet printing method.

9. 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, characterized in that the organic compound layer contains a compound represented by the following general formula (1-1) and a compound represented by the following general formula (2). (In the general formula (1-1) above, ring a and ring b each independently represent an aryl ring or a heteroaryl ring, and at least one hydrogen atom in these rings may be substituted with a deuterium atom, a halogen atom, a cyano group, or an alkyl group, aryl group, heteroaryl group, amino group, alkoxy group, aryloxy group, heteroaryloxy group, or silyl group which may have substituents. X １ and X ２ These are, independently, an oxygen atom, a sulfur atom, or N-R ６ Represents R ６ represents an aryl group, heteroaryl group, or alkyl group which may have substituents, and is linked by a linking group or single bond, X １ In this case, the ring a and X ２ In this case, it may be bonded to the aforementioned b ring. １ ~R ３ Each of these independently represents a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, or an alkyl group, aryl group, heteroaryl group, or group represented by general formula (1-2), which may have a substituent. However, R １ ~R ３ At least one of them represents a group represented by the general formula (1-2). In the general formula (1-2), the c ring represents a heteroaryl ring containing an atom of a group 16 element, and X ３ represents an oxygen atom or a sulfur atom, and * represents the bonding position with the general formula (1-1) above. (In the above general formula (2), R １１ ~R ２０ Each of these independently represents a hydrogen atom, or an alkyl group, aryl group, or heteroaryl group which may have a substituent. However, R １１ ~R ２０ At least one of these is a heteroaryl group containing an atom of a Group 16 element, which may have substituents.

10. A display device having a plurality of pixels, wherein at least one of the plurality of pixels comprises an organic light-emitting element as described in claim 9 and a transistor connected to the organic light-emitting element.

11. An imaging device comprising an optical unit having a plurality of lenses, an image sensor that receives light that has passed through the optical unit, and a display unit that displays an image captured by the image sensor, wherein the display unit includes the organic light-emitting element described in claim 9.

12. An electronic device comprising a display unit, a housing on which the display unit is provided, and a communication unit provided in the housing for communicating with the outside, wherein the display unit includes an organic light-emitting element as described in claim 9.

13. A lighting device comprising a light source and a member that transmits light emitted by the light source, wherein the light source includes the organic light-emitting element described in claim 9.

14. A mobile body comprising an aircraft body and a light fixture provided on the aircraft body, wherein the light fixture includes an organic light-emitting element as described in claim 9.

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