Composition and light-emitting device

Abstract

To provide a composition which is useful for manufacturing a light-emitting device of which the drive voltage is low.SOLUTION: Disclosed is a composition containing at least two kinds of compounds selected from among a low molecular compound (b), a low molecular compound (h) and a high molecular compound (H) and a solvent. At least one compound in the at least two kinds of compounds is the low molecular compound (b), and the low molecular compound (b) is a low molecular compound having a heterocyclic skeleton (b) in which six or more rings are condensed. The heterocyclic skeleton (b) contains a boron atom, a nitrogen atom, an oxygen atom, a sulfur atom and at least one selected from a selenium atom and an sp3 carbon atom in the condensed ring, and the low molecular compound (h) is a low molecular compound having a polycyclic aromatic hydrocarbon skeleton.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a composition and a light-emitting device. [Background technology]

[0002] Light-emitting devices such as organic electroluminescent devices can be suitably used for display and lighting applications. Patent Document 1, for example, describes a composition containing compound BC-G1, a polymer compound or a low-molecular compound not having a polycyclic aromatic hydrocarbon skeleton, and a solvent as a light-emitting material used to form a light-emitting layer of the light-emitting device. Patent Document 1, for example, describes a composition containing compound B-G1, a polymer compound or a low-molecular compound not having a polycyclic aromatic hydrocarbon skeleton, and a solvent.

[0003] [ka] [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-13757 [Patent Document 2] Japanese Patent Publication No. 2021-163964 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the driving voltage of a light-emitting device fabricated using the above composition is not necessarily sufficiently low. Therefore, an object of the present invention is to provide a composition useful for producing a light-emitting element with a low driving voltage, and to provide a light-emitting element formed using the composition. [Means for solving the problem]

[0006] The present invention provides the following [1] to

[13] . [1] A composition comprising at least two compounds selected from the group consisting of a low molecular weight compound (b), a low molecular weight compound (h), and a polymer compound (H), and a solvent, At least one compound among the at least two compounds is the low molecular weight compound (b), The low molecular weight compound (b) is a low molecular weight compound having a heterocyclic skeleton (b) in which six or more rings are fused. is a compound, The heterocyclic skeleton (b) comprises a boron atom, a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and sp 3 and at least one carbon atom selected from the group consisting of carbon atoms in the fused ring, the low molecular weight compound (h) is a low molecular weight compound having a polycyclic aromatic hydrocarbon skeleton, When the composition contains the polymer compound (H), the low molecular weight compound (b) satisfies the requirements (i) and (ii), A composition, wherein when the composition contains the low molecular weight compound (h), the low molecular weight compound (b) satisfies requirement (ii). (i) The boron atom, the nitrogen atom, the oxygen atom, the sulfur atom, the selenium atom, and the sp atom contained in the fused ring of the heterocyclic skeleton (b). 3 The total number of carbon atoms is 4 or more. (ii) The number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton (b) is 2 or more. [2] The composition according to [1], wherein the low molecular weight compound (b) is a low molecular weight compound that satisfies the requirements (i) and (ii). [3] The composition according to [1] or [2], wherein the heterocyclic skeleton (b) is a heterocyclic skeleton represented by formula (b1-1): [ka] [In the formula, Ring R b1 , ring R b2 , ring R b3 , ring R b4 and ring R b5each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X b1 , X b2 , X b3 and X b4 are each independently an oxygen atom, a sulfur atom, a selenium atom, -N(R xb )-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of the substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. However, X b1 , X b2 , X b3 and X b4 At least two of the following are -N(R xb )- is a group represented by the formula: R xb represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X b1 and ring R b1 , X b1 and ring R b2 , X b2 and ring R b1 , X b2 and ring R b3 , X b3 and ring R b2 , X b3 and ring R b4 , X b4 and ring R b4 , X b4 and ring R b5 , ring R b2 and ring R b3 , ring R b2 and ring R b5 , and ring R b3 and ring R b5may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded. .] [4] X b1 , the X b2 , the X b3 and the X b4 each independently represents an oxygen atom, a sulfur atom, or -N(R xb )-, a group represented by [3]. [5] sp 2 contained in the low molecular weight compound having a heterocyclic skeleton represented by the formula (b1-1) 3 The composition according to [3] or [4], wherein the total number of carbon atoms is 9 or more. [6] The composition according to any one of [3] to [5], wherein the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. [7] The composition according to any one of [3] to [6], wherein the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) is a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2). [ka] [In the formula, Ring R b1 , ring R b2 , ring R b3 , ring R b4 , ring R b5 , X b2 and X b4 represents the same meaning as above. Ring R Xb1 and ring R Xb2 each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ring R Xb1 and ring R b1 , ring R Xb1 and ring R Xb2 , and ring R Xb2 and ring R b4 may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded. [8] At least one compound among the at least two compounds is the polymer compound (H), The composition according to any one of [1] to [7], wherein the polymer compound (H) is a polymer compound containing at least one structural unit selected from the group consisting of a structural unit represented by formula (X) and a structural unit represented by formula (Y): [ka] [In the formula, a X1 and a X2 each independently represents an integer of 0 or greater. Ar X1 and Ar X3 each independently represents an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar X2 and Ar X4 are each independently an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar X2 When a plurality of Ar are present, they may be the same or different. X4When there are a plurality of groups, they may be the same or different. R X1 , R X2 and R X3 R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. X2 When there are multiple R's, they may be the same or different. X3 When there are multiple, they may be the same or different. [ka] [In the formula, Ar Y1 represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded to each other, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. [9] At least one compound among the at least two compounds is the low molecular weight compound (h), The composition according to any one of [1] to [8], wherein the low molecular weight compound (h) is a low molecular weight compound represented by formula (h-1). [ka] [In the formula, n 1h represents an integer greater than or equal to 0. Ar 1h is a hydrogen atom n directly bonded to a ring atom from a polycyclic aromatic hydrocarbon. 1hThese groups may have a substituent. When a plurality of the substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. R 1h represents an aryl group, a monovalent heterocyclic group, or a substituted amino group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R 1h When a plurality of are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar 1h and the substituents that may be present on R 1h may be bonded to each other to form a ring together with the atoms to which they are bonded.

[10] A composition comprising a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') and a solvent. [ka] [In the formula, Ring R b1 , ring R b2 , ring R b3 , ring R b4 and ring R b5 each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X b1 , X b2 , X b3 and X b4 are each independently an oxygen atom, a sulfur atom, a selenium atom, -N(R xb)-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of the substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. However, X b1 , X b2 , X b3 and X b4 At least two of the following are -N(R xb )- is a group represented by the formula: R xb represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X b1 and ring R b1 , X b1 and ring R b2 , X b2 and ring R b1 , X b2 and ring R b3 , X b3 and ring R b2 , X b3 and ring R b4 , X b4 and ring R b4 , X b4 and ring R b5 , ring R b2 and ring R b3 , ring R b2 and ring R b5 , and ring R b3 and ring R b5 may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atoms to which they are bonded. However, the sp 3The total number of carbon atoms is 9 or more, or the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents.

[11] The composition according to

[10] , wherein the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') is a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2'). [ka] [In the formula, Ring R b1 , ring R b2 , ring R b3 , ring R b4 , ring R b5 , X b2 and X b4 represents the same meaning as above. Ring R Xb1 and ring R Xb2 each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ring R Xb1 and ring R b1 , ring R Xb1 and ring R Xb2 , and ring R Xb2 and ring R b4 may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded.

[12] The composition according to any one of [1] to

[11] , further comprising at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, and an antioxidant.

[13] A light-emitting device having an anode, a cathode, and an organic layer provided between the anode and the cathode, The light-emitting device, wherein the organic layer is a layer formed using the composition according to any one of [1] to

[12] . [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a composition useful for producing a light-emitting device having a low driving voltage. Furthermore, according to the present invention, it is possible to provide a light-emitting device formed using the composition. DETAILED DESCRIPTION OF THE INVENTION

[0008] Preferred embodiments of the present invention will be described in detail below.

[0009] <Explanation of common terms> Terms commonly used in this specification have the following meanings unless otherwise specified.

[0010] "Room temperature" means 25°C.

[0011] Me represents a methyl group, Et represents an ethyl group, Bu represents a butyl group, i-Pr represents an isopropyl group, and t-Bu represents a tert-butyl group. The hydrogen atom may be a deuterium atom or a proton atom. In the formula representing a metal complex, the solid line representing a bond to a central metal means an ionic bond, a covalent bond, or a coordinate bond.

[0012] "Low molecular weight compounds" are compounds that do not have a molecular weight distribution and have a molecular weight of 1 x 10 4 The following compounds are meant:

[0013] "Polymer compounds" are compounds that have a molecular weight distribution and have a number average molecular weight of 1 x 10 in terms of polystyrene. 3 or more (e.g., 1×10 3 ~1×10 8 ) means a polymer in which The term "structural unit" refers to a unit that exists in one or more instances in a polymer compound. A structural unit that exists in two or more instances in a polymer compound is generally also called a "repeating unit." The polymer compound may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, or other forms. The terminal group of the polymer compound is preferably a stable group from the viewpoint of the light-emitting properties of the light-emitting device. The terminal group of the polymer compound is preferably a group that is conjugated to the main chain of the polymer compound, and examples thereof include an aryl group or a monovalent heterocyclic group that is bonded to the main chain of the polymer compound via a carbon-carbon bond.

[0014] The "alkyl group" may be either linear or branched. The number of carbon atoms in a linear alkyl group, not including the number of carbon atoms in the substituent, is usually 1 to 50, preferably 1 to 20, and more preferably 1 to 10. The number of carbon atoms in a branched alkyl group, not including the number of carbon atoms in the substituent, is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10.

[0015] The alkyl group may have a substituent. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a 2-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isoamyl group, a 2-ethylbutyl group, a hexyl group, a heptyl group, an octyl group, a 2-ethylhexyl group, a 3-propylheptyl group, a decyl group, a 3,7-dimethyloctyl group, a 2-ethyloctyl group, a 2-hexyldecyl group, and a dodecyl group. The alkyl group may also be a group in which some or all of the hydrogen atoms in these groups have been substituted with a substituent (for example, a trifluoromethyl group, a pentafluoroethyl group, a perfluorobutyl group, a perfluorohexyl group, a perfluorooctyl group, a 3-phenylpropyl group, a 3-(4-methylphenyl)propyl group, a 3-(3,5-di-hexylphenyl)propyl group, and a 6-ethyloxyhexyl group).

[0016] The number of carbon atoms in the "cycloalkyl group" is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10, not including the number of carbon atoms in the substituent. The cycloalkyl group may have a substituent. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents.

[0017] The number of carbon atoms in the "alkylene group" is usually 1 to 50, preferably 1 to 20, and more preferably 1 to 10, not including the number of carbon atoms in the substituent. The alkylene group may have a substituent. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents.

[0018] The number of carbon atoms in the "cycloalkylene group" is usually 3 to 50, preferably 4 to 20, and more preferably 5 to 10, not including the number of carbon atoms in the substituent. The cycloalkylene group may have a substituent. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, and groups in which some or all of the hydrogen atoms in the groups have been substituted with substituents.

[0019] An "aromatic hydrocarbon group" refers to a group obtained by removing one or more hydrogen atoms directly bonded to a carbon atom that constitutes a ring from an aromatic hydrocarbon. A group obtained by removing one hydrogen atom directly bonded to a carbon atom that constitutes a ring from an aromatic hydrocarbon is also called an "aryl group." A group obtained by removing two hydrogen atoms directly bonded to a carbon atom that constitutes a ring from an aromatic hydrocarbon is also called an "arylene group." The number of carbon atoms in the aromatic hydrocarbon group is usually 6 to 60, preferably 6 to 40, and more preferably 6 to 20, not including the number of carbon atoms in the substituent.

[0020] Examples of "aromatic hydrocarbon groups" include monocyclic aromatic hydrocarbons (e.g., benzene) or polycyclic aromatic hydrocarbons (e.g., bicyclic aromatic hydrocarbons such as naphthalene, indene, naphthoquinone, indenone, and tetralone; tricyclic aromatic hydrocarbons such as anthracene, phenanthrene, dihydrophenanthrene, dibenzocycloheptane, fluorene, anthraquinone, phenanthoquinone, and fluorenone; tetracyclic aromatic hydrocarbons such as benzanthracene, benzophenanthrene, and benzofluorene; pentacyclic aromatic hydrocarbons such as dibenzanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene, and benzofluoranthene; hexacyclic aromatic hydrocarbons such as spirobifluorene; and heptacyclic aromatic hydrocarbons such as benzospirobifluorene and acenaphthofluoranthene), in which one or more hydrogen atoms directly bonded to the carbon atoms constituting the ring have been removed. Aromatic hydrocarbon groups include groups in which multiple of these groups are bonded. The aromatic hydrocarbon group may have a substituent.

[0021] The "alkoxy group" may be either linear or branched. The number of carbon atoms in a linear alkoxy group, not including the number of carbon atoms in the substituent, is usually 1 to 50, preferably 1 to 20, and more preferably 1 to 10. The number of carbon atoms in a branched alkoxy group, not including the number of carbon atoms in the substituent, is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10. The alkoxy group may have a substituent. Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropyloxy group, a butyloxy group, a hexyloxy group, a 2-ethylhexyloxy group, a 3,7-dimethyloctyloxy group, a lauryloxy group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents.

[0022] The number of carbon atoms in the "cycloalkoxy group" is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10, not including the number of carbon atoms in the substituent. The cycloalkoxy group may have a substituent. Examples of the cycloalkoxy group include a cyclohexyloxy group and a group in which some or all of the hydrogen atoms are substituted. Substituted groups are included.

[0023] The number of carbon atoms in the "aryloxy group" is usually 6 to 60, preferably 6 to 40, and more preferably 6 to 20, not including the number of carbon atoms in the substituent. The aryloxy group may have a substituent. Examples of the aryloxy group include a phenoxy group, a naphthyloxy group, an anthracenyloxy group, a pyrenyloxy group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents.

[0024] A "heterocyclic group" refers to a group obtained by removing, from a heterocyclic compound, one or more hydrogen atoms directly bonded to atoms constituting the ring (carbon atoms or heteroatoms). Among heterocyclic groups, an "aromatic heterocyclic group", which is a group obtained by removing, from an aromatic heterocyclic compound, one or more hydrogen atoms directly bonded to atoms constituting the ring, is preferred. A group obtained by removing, from a heterocyclic compound, p hydrogen atoms (p represents an integer of 1 or more) directly bonded to atoms constituting the ring is also called a "p-valent heterocyclic group". A group obtained by removing, from an aromatic heterocyclic compound, p hydrogen atoms directly bonded to atoms constituting the ring is also called a "p-valent aromatic heterocyclic group".

[0025] Examples of the "aromatic heterocyclic compound" include compounds in which the heterocycle itself exhibits aromaticity, such as azole, thiophene, furan, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, and carbazole, as well as compounds in which an aromatic ring is condensed with a heterocycle, even if the heterocycle itself does not exhibit aromaticity, such as phenoxazine, phenothiazine, and benzopyran.

[0026] The number of carbon atoms in the heterocyclic group, not including the number of carbon atoms in the substituent, is usually 1 to 60, preferably 2 to 40, and more preferably 3 to 20. The number of heteroatoms in the heterocyclic group, not including the number of heteroatoms in the substituent, is usually 1 to 30, preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 3.

[0027] Examples of the heterocyclic group include monocyclic heterocyclic compounds (e.g., furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, triazole, tetrazole, pyridine, diazabenzene, and triazine), and polycyclic heterocyclic compounds (e.g., bicyclic heterocyclic compounds such as azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, benzodiazole, benzothiadiazole, benzotriazole, benzothiophene dioxide, benzothiophene oxide, and benzopyranone; dibenzofuran, dibenzothiophene, dibenzothiophene dioxide, dibenzothiophene oxide, dibenzopyranone, dibenzoborole, dibenzosilole, dibenzophosphole, dibenzoselenophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, etc.). tricyclic heterocyclic compounds such as benzophenone, acridone, phenazaborine, phenophosphazine, phenoselenazine, phenazasiline, azaanthracene, diazaanthracene, azaphenanthrene, and diazaphenanthrene; tetracyclic heterocyclic compounds such as hexaazatriphenylene, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, and benzonaphthothiophene; dibenzocarbazole, indolocarbazole, indenocarbazole, Examples of heterocyclic compounds include 5-ring heterocyclic compounds such as azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole, and diazaindenocarbazole; 6-ring heterocyclic compounds such as carbazolocarbazole, benzoindolocarbazole, and benzoindenocarbazole; and 7-ring heterocyclic compounds such as dibenzoindolocarbazole and dibenzoindenocarbazole. Examples of heterocyclic groups include groups in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from the above heterocyclic compounds. Heterocyclic groups include groups in which multiple such groups are bonded. The heterocyclic group may have a substituent.

[0028] The term "halogen atom" refers to a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0029] The "amino group" may have a substituent, and is preferably a substituted amino group (i.e., a secondary amino group or a tertiary amino group, more preferably a tertiary amino group). The substituent that the amino group has is preferably an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may further have a substituent. When the amino group has multiple substituents, they may be the same or different, and may be bonded to each other to form a ring together with the nitrogen atom to which they are bonded. Examples of the substituted amino group include a dialkylamino group, a dicycloalkylamino group, a diarylamino group, and groups in which some or all of the hydrogen atoms in these groups have been further substituted with substituents. Examples of the substituted amino group include a dimethylamino group, a diethylamino group, a diphenylamino group, a bis(methylphenyl)amino group, a bis(3,5-di-tert-butylphenyl)amino group, and groups in which some or all of the hydrogen atoms in these groups have been further substituted with substituents.

[0030] The "alkenyl group" may be either linear or branched. The number of carbon atoms in a linear alkenyl group, not including the number of carbon atoms in substituents, is usually 2 to 50, preferably 2 to 20, and more preferably 3 to 10. The number of carbon atoms in a branched alkenyl group, not including the number of carbon atoms in substituents, is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10.

[0031] The number of carbon atoms in the "cycloalkenyl group" is usually 3 to 50, preferably 4 to 20, and more preferably 5 to 10, not including the number of carbon atoms in substituents. The alkenyl group and the cycloalkenyl group may have a substituent. Examples of the alkenyl group include a vinyl group, a 1-propenyl group, a 2-butenyl group, a 3-butenyl group, a 3-pentenyl group, a 4-pentenyl group, a 1-hexenyl group, a 5-hexenyl group, a 7-octenyl group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with a substituent. Examples of the cycloalkenyl group include a cyclohexenyl group, a cyclohexadienyl group, a cyclooctatrienyl group, a norbornylenyl group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with a substituent.

[0032] The "alkynyl group" may be either linear or branched. The number of carbon atoms in the alkynyl group, not including the carbon atoms of the substituents, is usually 2 to 50, preferably 2 to 20, and more preferably 3 to 10. The number of carbon atoms in a branched alkynyl group, not including the carbon atoms of the substituents, is usually 4 to 50, preferably 4 to 20, and more preferably 4 to 10.

[0033] The number of carbon atoms in the "cycloalkynyl group" is usually 4 to 50, preferably 5 to 20, and more preferably 6 to 10, not including the carbon atoms of the substituents. The alkynyl group and the cycloalkynyl group may have a substituent. Examples of the alkynyl group include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 2-butynyl group, a 3-butynyl group, a 3-pentynyl group, a 4-pentynyl group, a 1-hexynyl group, a 5-hexynyl group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with a substituent. Examples of the cycloalkynyl group include a cyclooctynyl group and groups in which some or all of the hydrogen atoms in these groups have been substituted with a substituent.

[0034] The "crosslinking group" is a group that can generate a new bond by heating, ultraviolet irradiation, near-ultraviolet irradiation, visible light irradiation, infrared irradiation, radical reaction, or the like. Among them, at least one crosslinking group selected from the crosslinking group A (that is, at least one group selected from the groups represented by formulae (XL-1) to (XL-19)) is preferred.

[0035] [ka] [In the formula, R XL represents a methylene group, an oxygen atom, or a sulfur atom; n XL represents an integer from 0 to 5. XL When there are multiple n, they may be the same or different. XL When there are a plurality of groups, they may be the same or different. *1 indicates the bonding position. These bridging groups may have a substituent, and when there are a plurality of such substituents, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded.]

[0036] Examples of the "substituent" include a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an amino group, a substituted amino group, an alkenyl group, a cycloalkenyl group, an alkynyl group, and a cycloalkynyl group. The substituent may be a bridging group. When multiple substituents are present, they may be the same or different. When multiple substituents are present, they may be bonded to each other to form a ring together with the atoms to which they are bonded, but it is preferable that they do not form a ring.

[0037] Examples of the "divalent group" include an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, -Si(R 0 )2-, -Ge(R 0 )2-, a group represented by -N(R 0 )-, -B(R 0 )-, a group represented by -P(R 0 )-, a group represented by -(O=)P(R 0)-, a group represented by -O-, a group represented by -S-, a group represented by -Se-, a group represented by -S(=O)-, a group represented by -S(=O)2-, and a group represented by -C(=O)-. Divalent groups include groups in which a plurality of these groups are bonded. The divalent group may have a substituent. When a plurality of the substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R 0 represents a hydrogen atom or a substituent. 0 When a plurality of are present, they may be the same or different and may be bonded to each other to form a ring together with the atom to which they are bonded. R 0 Examples of the aryl group include a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group, a halogen atom, and a cyano group, and preferably a hydrogen atom, an alkyl group, a cycloalkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, a substituted amino group, a halogen atom, and a cyano group. The substituents are an alkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of the substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. The "divalent or higher valent group" may be a divalent group or a trivalent or higher valent group. A trivalent or higher valent group means a group in which one or more hydrogen atoms have been removed from a divalent group. For example, in the case of a trivalent group, -N(R 0 )-, -B(R 0 )-, -P(R 0 )- and -(O=)P(R 0 )-, R 0 represents a bond. For example, in the case of a tetravalent group, -Si(R 0 )2- and -Ge(R 0 )2-, R 0 represents a bond.

[0038] The divalent or more groups include groups in which multiple divalent or more groups are bonded. The divalent or more groups may have a substituent. When multiple substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.

[0039] In this specification, the absolute value of the difference between the energy level of the lowest excited triplet state and the energy level of the lowest excited singlet state (hereinafter referred to as "ΔE ST The value of ΔE is calculated as follows. First, the ground state of the compound is optimized using the density functional theory at the B3LYP level. In this case, 6-31G* is used as the basis function. Then, using the optimized structure, the ΔE of the compound is calculated using the time-dependent density functional theory at the B3LYP level. ST However, if an atom for which 6-31G* cannot be used is included, LANL2DZ is used for that atom. The quantum chemistry calculation program used for the calculation is Gaussian09.

[0040] [Low molecular compound (b)] The low molecular weight compound (b) of this embodiment is a low molecular weight compound having a heterocyclic skeleton (b) in which six or more rings are fused (hereinafter also referred to as "a heterocyclic skeleton (b) with six or more rings"). The heterocyclic skeleton (b) contains a boron atom, a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and sp 3 and at least one carbon atom selected from the group consisting of carbon atoms in the fused ring. The low molecular weight compound (b) is preferably a compound that does not contain a transition metal element (that is, a compound that is composed only of main group elements).

[0041] The number of carbon atoms contained in the fused ring of the heterocyclic skeleton (b), not including the number of carbon atoms of the substituent, is usually 1 or more, and may be 5 or more; since the driving voltage of the light-emitting device of this embodiment is lower, it is preferably 10 or more, more preferably 15 or more, even more preferably 20 or more, particularly preferably 25 or more, especially preferably 30 or more, may be 35 or more, or may be 40 or more. Furthermore, the number of carbon atoms contained in the fused ring of the heterocyclic skeleton (b), not including the number of carbon atoms of the substituent, is, for example, usually 500 or less, may be 300 or less, or may be 100 or less; since the driving voltage of the light-emitting device of this embodiment is lower, it is preferably 90 or less, more preferably 80 or less, even more preferably 70 or less, particularly preferably 60 or less, and especially preferably 50 or less. The number of heteroatoms contained in the fused ring of the heterocyclic skeleton (b), not including the number of heteroatoms of the substituents, is usually 1 or more, and may be 2 or more; since this reduces the driving voltage of the light-emitting device of this embodiment, it is preferably 3 or more, more preferably 4 or more, even more preferably 5 or more, and particularly preferably 6 or more. The number of heteroatoms contained in the fused ring of the heterocyclic skeleton (b), not including the number of heteroatoms of the substituents, is usually 50 or less, and may be 40 or less, or may be 30 or less; since this reduces the driving voltage of the light-emitting device of this embodiment, it is preferably 25 or less, more preferably 20 or less, even more preferably 15 or less, particularly preferably 10 or less, and particularly preferably 8 or less. The number of boron atoms contained in the fused ring of the heterocyclic skeleton (b) includes the number of boron atoms of the substituents. The number of boron atoms contained in the fused ring of the heterocyclic skeleton (b) is usually 20 or less, not including the number of boron atoms in the substituents, and may be 15 or less, but is preferably 10 or less, more preferably 7 or less, even more preferably 5 or less, and particularly preferably 3 or less, because this reduces the driving voltage of the light-emitting device of this embodiment.

[0042] The nitrogen atom, oxygen atom, sulfur atom, selenium atom and sp atom contained in the fused ring of the heterocyclic skeleton (b) 3 The total number of carbon atoms, not including the number of atoms of the substituents, is 1 or more (however, when the heterocyclic skeleton (b) satisfies the requirement (ii), it is 2 or more). Since the driving voltage of the light-emitting device of this embodiment becomes lower, it is preferably 2 or more, more preferably 3 or more, and particularly preferably 4 or more. In addition, the nitrogen atom, oxygen atom, sulfur atom, selenium atom and sp atom contained in the fused ring of the heterocyclic skeleton (b) 3 The total number of carbon atoms, not including the number of atoms of the substituents, is usually 30 or less, may be 25 or less, or may be 20 or less, and is preferably 15 or less, more preferably 10 or less, even more preferably 8 or less, particularly preferably 6 or less, and especially preferably 4 or less, since this reduces the driving voltage of the light-emitting element of this embodiment.

[0043] The boron atom, nitrogen atom, oxygen atom, sulfur atom, selenium atom and sp atom contained in the fused ring of the heterocyclic skeleton (b) 3 The total number of carbon atoms, not including the number of atoms of the substituents, is 2 or more (however, when the heterocyclic skeleton (b) satisfies the requirement (i), it is 4 or more. When the heterocyclic skeleton (b) satisfies the requirement (ii), it is 3 or more). Since the driving voltage of the light-emitting device of this embodiment becomes lower, it is preferably 3 or more, more preferably 4 or more, even more preferably 5 or more, and particularly preferably 6 or more. In addition, the number of boron atoms, nitrogen atoms, oxygen atoms, sulfur atoms, selenium atoms, and sp atoms contained in the fused rings of the heterocyclic skeleton (b) is preferably 1 or more. 3 The total number of carbon atoms, not including the number of atoms of the substituents, is usually 50 or less, may be 40 or less, or may be 30 or less, and is preferably 25 or less, more preferably 20 or less, even more preferably 15 or less, particularly preferably 10 or less, and especially preferably 8 or less, since this reduces the driving voltage of the light-emitting element of this embodiment.

[0044] When the heterocyclic skeleton (b) contains a nitrogen atom in the fused ring, the number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton (b), not including the number of nitrogen atoms of the substituent, is 1 or more (however, when the heterocyclic skeleton (b) satisfies requirement (ii), the number is 2 or more). Since the driving voltage of the light-emitting device of this embodiment is lower, the number is preferably 2 or more, more preferably 3 or more, and particularly preferably 4 or more. Furthermore, when the heterocyclic skeleton (b) contains a nitrogen atom in the fused ring, the number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton (b), not including the number of nitrogen atoms of the substituent, is usually 30 or less, and may be 25 or less, or may be 20 or less. Since the driving voltage of the light-emitting device of this embodiment is lower, the number is preferably 15 or less, more preferably 10 or less, even more preferably 8 or less, particularly preferably 6 or less, and particularly preferably 4 or less.

[0045] When the heterocyclic skeleton (b) contains a nitrogen atom, the driving voltage of the light-emitting element of this embodiment becomes lower. Therefore, it is preferable that at least one of the nitrogen atoms contained in the fused ring of the heterocyclic skeleton (b) is a nitrogen atom that does not form a double bond, and it is more preferable that all of the nitrogen atoms contained in the heterocyclic skeleton (b) are nitrogen atoms that do not form a double bond.

[0046] When the heterocyclic skeleton (b) contains a nitrogen atom in a fused ring, the number of nitrogen atoms not forming a double bond contained in the fused ring of the heterocyclic skeleton (b) is 1 or more (however, when the heterocyclic skeleton (b) satisfies the requirement (ii), the number is 2 or more), not including the number of nitrogen atoms not forming a double bond of a substituent. This is preferable because the driving voltage of the light-emitting device of this embodiment is lower. is 2 or more, more preferably 3 or more, and even more preferably 4 or more. When the heterocyclic skeleton (b) contains a nitrogen atom in a fused ring, the number of nitrogen atoms not forming a double bond contained in the fused ring of the heterocyclic skeleton (b), not including the number of nitrogen atoms not forming a double bond in the substituent, is usually 30 or less, may be 25 or less, or may be 20 or less, and is preferably 15 or less, more preferably 10 or less, even more preferably 8 or less, particularly preferably 6 or less, and especially preferably 4 or less, since this further reduces the driving voltage of the light-emitting element of this embodiment.

[0047] The heterocyclic skeleton (b) preferably contains a boron atom and at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, and a selenium atom in the fused ring, because this lowers the driving voltage of the light-emitting element of this embodiment; more preferably contains a boron atom and at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom in the fused ring; still more preferably contains a boron atom and at least one atom selected from the group consisting of a nitrogen atom and an oxygen atom in the fused ring; particularly preferably contains a boron atom and a nitrogen atom in the fused ring; and especially preferably contains a nitrogen atom that does not form a double bond with the boron atom in the fused ring.

[0048] The number of rings constituting the fused rings of the heterocyclic skeleton (b) is preferably 7 or more, more preferably 8 or more, and even more preferably 9 or more, since this lowers the driving voltage of the light-emitting device of this embodiment. The number of rings constituting the fused rings of the heterocyclic skeleton (b) is usually 60 or less, and is preferably 40 or less, more preferably 30 or less, even more preferably 25 or less, particularly preferably 20 or less, and especially preferably 15 or less, since this lowers the driving voltage of the light-emitting device of this embodiment.

[0049] The low molecular weight compound (b) having a heterocyclic skeleton (b) can also be referred to as a low molecular weight compound having a heterocyclic group (b) containing a heterocyclic skeleton (b).

[0050] The heterocyclic group (b) is a group consisting of a boron atom, a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and sp 3 and at least one kind selected from the group consisting of carbon atoms in a fused ring, from a heterocyclic skeleton (b) having 6 or more rings, by removing one or more hydrogen atoms directly bonded to atoms constituting the ring, and the group may have a substituent.

[0051] The substituent that the heterocyclic group (b) may have is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, because this reduces the driving voltage of the light-emitting element of this embodiment; more preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group; even more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, or a substituted amino group; and particularly preferably an alkyl group, a cycloalkyl group, an aryl group, or a substituted amino group, and these groups may further have a substituent.

[0052] The aryl group in the substituent that the heterocyclic group (b) may have is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon, since this reduces the driving voltage of the light-emitting element of this embodiment; more preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic, bicyclic, or tricyclic aromatic hydrocarbon; even more preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic or tricyclic aromatic hydrocarbon; and particularly preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic aromatic hydrocarbon; and these groups may further have a substituent.

[0053] The aryl group in the substituent that the heterocyclic group (b) may have is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from benzene, naphthalene, indene, anthracene, phenanthrene, dihydrophenanthrene, or fluorene, because this further reduces the driving voltage of the light-emitting element of this embodiment; more preferably, a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from benzene, naphthalene, anthracene, phenanthrene, or fluorene; even more preferably, a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from benzene or fluorene; and these groups may have a substituent. The aryl group in the substituent that the heterocyclic group (b) may have may be an aryl group having three or more substituents as described below.

[0054] The monovalent heterocyclic group in the substituent that the heterocyclic group (b) may have is preferably a group obtained by removing one hydrogen atom directly bonded to an atom constituting the ring from a monocyclic or bicyclic to hexacyclic heterocyclic compound, more preferably a group obtained by removing one hydrogen atom directly bonded to an atom constituting the ring from a monocyclic, bicyclic or tricyclic heterocyclic compound, even more preferably a group obtained by removing one hydrogen atom directly bonded to an atom constituting the ring from a monocyclic or tricyclic heterocyclic compound, and particularly preferably a group obtained by removing one hydrogen atom directly bonded to an atom constituting the ring from a tricyclic heterocyclic compound, and these groups may have a substituent, because this reduces the driving voltage of the light-emitting element of this embodiment.

[0055] The monovalent heterocyclic group in the substituent that the heterocyclic group (b) may have is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from furan, thiophene, pyrrole, diazole, triazole, pyridine, diazabenzene, triazine, benzofuran, benzothiophene, indole, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, acridone, azaanthracene, diazaanthracene, azaphenanthrene, or diazaphenanthrene, because this further reduces the driving voltage of the light-emitting element of this embodiment, and more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, It is a group in which one hydrogen atom directly bonded to a ring-constituting atom has been removed from dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine, or 5,10-dihydrophenazine, more preferably a group in which one hydrogen atom directly bonded to a ring-constituting atom has been removed from pyridine, diazabenzene, triazine, carbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, or 5,10-dihydrophenazine, particularly preferably a group in which one hydrogen atom directly bonded to a ring-constituting atom has been removed from carbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, or 5,10-dihydrophenazine, and particularly preferably a group in which one hydrogen atom directly bonded to a ring-constituting atom has been removed from carbazole, and these groups may have a substituent. The monovalent heterocyclic group in the substituent that the heterocyclic group (b) may have may be a monovalent heterocyclic group having three or more substituents as described below.

[0056] In the substituted amino group in the substituent that the heterocyclic group (b) may have, the substituent that the amino group has is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group, and these groups may further have a substituent. Examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituent that the amino group has are the same as the examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituent that the heterocyclic group (b') may have, respectively.

[0057] The substituent that the heterocyclic group (b) may have further includes the following: Since the driving voltage of the light-emitting element of the embodiment is lower, the group is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, even more preferably an alkyl group, a cycloalkyl group, or an aryl group, and particularly preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent, but preferably do not have a further substituent. Examples and preferred ranges of the aryl group, monovalent heterocyclic group, and substituted amino group in the substituent that the heterocyclic group (b) may further have are the same as the examples and preferred ranges of the aryl group, monovalent heterocyclic group, and substituted amino group in the substituent that the heterocyclic group (b') may have.

[0058] The term "nitrogen atom not forming a double bond" means a nitrogen atom that is bonded to three other atoms via single bonds. "Containing a nitrogen atom not forming a double bond in the ring" means that -N(R N )-(wherein, R N represents a hydrogen atom or a substituent.) or the formula:

[0059] [ka] This means that the compound contains a group represented by the formula: R N Examples and preferred ranges of R xb The examples and preferred ranges are the same as those of the above.

[0060] The heterocyclic skeleton (b) preferably satisfies at least one of the requirements (i) and (ii), and more preferably satisfies both the requirements (i) and (ii), since this reduces the driving voltage of the light-emitting element of this embodiment.

[0061] The low molecular weight compound (b) is preferably a thermally activated delayed fluorescence (TADF) compound, since this lowers the driving voltage of the light-emitting device of this embodiment.

[0062] ΔE of low molecular weight compound (b) ST may be, for example, 2.0 eV or less, 1.5 eV or less, 1.0 eV or less, 0.80 eV or less, 0.60 eV or less, or 0.55 eV or less, but since the driving voltage of the light-emitting element of this embodiment is lower, it is preferably 0.50 eV or less, more preferably 0.45 eV or less, even more preferably 0.40 eV or less, particularly preferably 0.35 eV or less, and especially preferably 0.32 eV or less, and may be 0.31 eV or less, or may be 0.30 eV or less. ST may be, for example, 0.001 eV or more, 0.01 eV or more, 0.10 eV or more, 0.15 eV or more, 0.20 eV or more, or 0.25 eV or more.

[0063] The molecular weight of the low molecular weight compound (b) is usually 1×10 2 That's 2 x 10 2 May be greater than 3 x 10 2 May be more than 4 x 10 2 or more, and is preferably 5×10 2More preferably, it is 7×10 2 More preferably, 8×10 2 More preferably, 9×10 2 More preferably, it is 1.0×10 3 That is 1.1 x 10 3 It may be 1.2 x 10 or more. 3 It may be 1.3 x 10 or more. 3 It may be more than 1.4 x 10 3 It may be 1.5 x 10 or more. 3 It may be 1.6 x 10 or more. 3 The molecular weight of the low molecular weight compound (b) is usually 1×10 4 The driving voltage of the light-emitting device of this embodiment is lowered, and the synthesis of the low-molecular compound (b) is easy. Therefore, it is preferably 8×10 3 or less, and more preferably 6×10 3 or less, and particularly preferably 4×10 3 or less, and particularly preferably 2 × 10 3 The following is the result.

[0064] sp contained in low molecular weight compound (b) 3 The total number of carbon atoms may be, for example, 1 or more, 3 or more, 5 or more, or 7 or more, and is preferably 9 or more, more preferably 12 or more, even more preferably 15 or more, particularly preferably 18 or more, 20 or more, 22 or more, or 24 or more, since the driving voltage of the light-emitting element of this embodiment is lowered. 3 The total number of carbon atoms may be, for example, 1000 or less, 800 or less, 600 or less, 400 or less, or 200 or less, and is preferably 100 or less, more preferably 70 or less, even more preferably 50 or less, and particularly preferably 30 or less, since this reduces the driving voltage of the light-emitting element of this embodiment and makes it easy to synthesize the low molecular weight compound (b).

[0065] The low molecular weight compound (b) may have at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. Since the driving voltage of the light-emitting device of this embodiment becomes lower, the low molecular weight compound (b) preferably has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents, and more preferably has an aryl group having three or more substituents, and these groups may further have substituents. Examples and preferred ranges of the aryl group and monovalent heterocyclic group in the aryl group having three or more substituents and the monovalent heterocyclic group having three or more substituents are the same as the examples and preferred ranges of the aryl group and monovalent heterocyclic group in the substituent that the heterocyclic group (b) may have, respectively. In the aryl group having three or more substituents and the monovalent heterocyclic group having three or more substituents, examples and preferred ranges of the substituents are the same as the examples and preferred ranges of the substituents that the substituents that the heterocyclic group (b) may further have.

[0066] In the aryl group having three or more substituents and the monovalent heterocyclic group having three or more substituents, the number of substituents is usually 3 to 50, and is preferably 3 to 20, more preferably 3 to 15, even more preferably 3 to 10, particularly preferably 3 to 7, especially preferably 3 to 5, and especially preferably 3 or 4, because this lowers the driving voltage of the light-emitting element of this embodiment and facilitates the synthesis of the low molecular weight compound (b).

[0067] When the low molecular weight compound (b) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents, the total number of the aryl group having three or more substituents and the monovalent heterocyclic group having three or more substituents contained in the low molecular weight compound (b) is usually 1 to 50, and is preferably 1 to 20, more preferably 1 to 10, even more preferably 1 to 7, and particularly preferably 1 to 4, because this reduces the driving voltage of the light-emitting element of this embodiment and facilitates the synthesis of the low molecular weight compound (b).

[0068] When the low molecular weight compound (b) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents, there are no particular limitations on the low molecular weight compound (b) as long as it has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. When the low molecular weight compound (b) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents, the low molecular weight compound (b) may have at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents, for example, as a substituent that the heterocyclic group (b) may have, or may have as a further substituent that the substituent that the heterocyclic group (b) may have, but preferably has it as a substituent that the heterocyclic group (b) may have, because this further reduces the driving voltage of the light-emitting element of this embodiment.

[0069] When the low molecular weight compound (b) has an aryl group having three or more substituents, the aryl group in the substituent that the heterocyclic group (b) may have may be an aryl group having three or more substituents, and in the substituted amino group in the substituent that the heterocyclic group (b) may have, the aryl group in the substituent that the amino group has may be an aryl group having three or more substituents. Furthermore, when the low molecular weight compound (b) has a monovalent heterocyclic group having three or more substituents, the monovalent heterocyclic group in the substituent that the heterocyclic group (b) may have may be a monovalent heterocyclic group having three or more substituents, and in the substituted amino group in the substituent that the heterocyclic group (b) may have, the monovalent heterocyclic group in the substituent that the amino group has may be a monovalent heterocyclic group having three or more substituents.

[0070] The low molecular weight compound (b) lowers the driving voltage of the light emitting device of this embodiment, so the sp 3 It is preferable that the total number of carbon atoms is 9 or more, or that the low molecular weight compound (b) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. 3 The total number of carbon atoms is more preferably 9 or more, and the sp 3 It is more preferable that the total number of carbon atoms is 9 or more, and the low molecular weight compound (b) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents.

[0071] The low molecular weight compound (b) is preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0) (i.e., the heterocyclic skeleton (b) is a heterocyclic skeleton represented by formula (b0)), since this lowers the driving voltage of the light-emitting element of this embodiment. Unless otherwise specified, the examples and preferred ranges of the low molecular weight compound (b) described above can also be applied as examples and preferred ranges to low molecular weight compounds having a heterocyclic skeleton represented by the formula (b0) described below.

[0072] [ka] [In the formula, X b1 and X b2 are each independently an oxygen atom, a sulfur atom, a selenium atom, -N(R xb )-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. R xb represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar b1 , Ar b2 and Ar b3 each independently represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X b1 and Ar b1 , X b1 and Ar b2 , X b2 and Ar b1 , X b2 and Ar b3 , and Ar b2 and Ar b3 may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atoms to which they are bonded. However, the formula (b0) satisfies at least one of the requirements (b0-i) and (b0-ii). (b0-i)Ar b1 , Ar b2 and Ar b3 At least one of the groups is a polycyclic aromatic hydrocarbon group or a polycyclic heterocyclic group, and these groups may have a substituent. (b0-ii)X b1 and Ar b1 , X b1 and Ar b2 , X b2 and Ar b1 , X b2 and Ar b3 , and Ar b2 and Ar b3 At least one of the groups is bonded directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents is present, they may be the same or different and may be bonded to each other to form a ring together with the atom to which they are bonded.]

[0073] When the low molecular weight compound (b) satisfies the requirement (i), the boron atom, nitrogen atom, oxygen atom, sulfur atom, selenium atom, and sp atom contained in the fused ring of the heterocyclic skeleton represented by formula (b0) are 3 The total number of carbon atoms, not including the number of atoms of the substituents, is 4 or more. When the low-molecular-weight compound (b) satisfies the requirement (i), the boron atom, nitrogen atom, oxygen atom, sulfur atom, selenium atom, and sp atom contained in the fused ring of the heterocyclic skeleton represented by formula (b0) are 3 Examples and preferred ranges of the total number of carbon atoms include the boron atom, nitrogen atom, oxygen atom, sulfur atom, selenium atom, and sp atom contained in the fused ring of the heterocyclic skeleton (b) when the low molecular weight compound (b) satisfies the requirement (i). 3 The examples and preferred ranges for the total number of carbon atoms are the same as those for the total number of carbon atoms. When low molecular weight compound (b) satisfies requirement (ii), the number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton represented by formula (b0), not including the number of nitrogen atoms of the substituent, is 2 or more. When low molecular weight compound (b) satisfies requirement (ii), examples and preferred ranges of the number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton represented by formula (b0) are the same as the examples and preferred ranges of the number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton (b) when low molecular weight compound (b) satisfies requirement (ii).

[0074] X b1 and X b2 is preferably an oxygen atom, a sulfur atom, a selenium atom, or —N(R xb )- or an alkylene group, and more preferably an oxygen atom, a sulfur atom, a selenium atom, or an —N(R xb )-, and more preferably an oxygen atom, a sulfur atom, or a group represented by —N(R xb )-, and particularly preferably an oxygen atom or -N(R xb )-, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded.

[0075] X b1 and X b2 The alkylene group in is preferably a methylene group, ethylene group, propylene group, butylene group, pentylene group, or hexylene group, more preferably a methylene group, ethylene group, or propylene group, and even more preferably a methylene group, and these groups may have a substituent. X b1 and X b2 The cycloalkylene group in The alkyl group is preferably a cyclobutylene group, a cyclopentylene group, or a cyclohexylene group, and more preferably a cyclohexylene group, and these groups may have a substituent. X b1 and X b2The examples and preferred range of the substituents which may be possessed by the heterocyclic group (b) are the same as the examples and preferred range of the substituents which may be possessed by the heterocyclic group (b).

[0076] R xb is preferably an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, more preferably an aryl group or a monovalent heterocyclic group, and even more preferably an aryl group, since this reduces the driving voltage of the light-emitting element of this embodiment, and these groups may have a substituent. R xb The examples and preferred ranges of the aryl group and the monovalent heterocyclic group in are the same as the examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituent that the heterocyclic group (b) may have, respectively. R xb The examples and preferred range of the substituents which may be possessed by the heterocyclic group (b) are the same as the examples and preferred range of the substituents which may be possessed by the heterocyclic group (b).

[0077] Ar b1 , Ar b2 and Ar b3 The aromatic hydrocarbon group in the formula (I) is a monocyclic aromatic hydrocarbon group or a polycyclic aromatic hydrocarbon group, and these groups may have a substituent. Ar b1 , Ar b2 and Ar b3 In the formula (I), the monocyclic aromatic hydrocarbon group is a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a monocyclic aromatic hydrocarbon, and the group may have a substituent.

[0078] Ar b1 , Ar b2 and Ar b3 In the formula, the number of carbon atoms in the monocyclic aromatic hydrocarbon group, not including the number of carbon atoms in the substituent, is preferably 6 to 20, more preferably 6 to 10, and even more preferably 6. The monocyclic aromatic hydrocarbon in the monocyclic aromatic hydrocarbon group is preferably benzene, since this lowers the driving voltage of the light-emitting device of this embodiment.

[0079] Ar b1 , Ar b2 and Ar b3 In the formula (I), the polycyclic aromatic hydrocarbon group is a group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting the ring from a polycyclic aromatic hydrocarbon, and the group may have a substituent.

[0080] Ar b1 , Ar b2 and Ar b3 In the formula, the number of carbon atoms of the polycyclic aromatic hydrocarbon group is usually 7 to 60, preferably 8 to 60, more preferably 9 to 40, and even more preferably 10 to 20, not including the number of carbon atoms of the substituent. Ar b1 , Ar b2 and Ar b3 In the above, the polycyclic aromatic hydrocarbon in the polycyclic aromatic hydrocarbon group is preferably a bicyclic to heptacyclic aromatic hydrocarbon, more preferably a bicyclic to pentacyclic aromatic hydrocarbon, even more preferably a bicyclic or tricyclic aromatic hydrocarbon, particularly preferably naphthalene, indene, anthracene, phenanthrene, dihydrophenanthrene, or fluorene, since this reduces the driving voltage of the light-emitting element of this embodiment.

[0081] Ar b1 , Ar b2 and Ar b3 The aromatic hydrocarbon group in the formula (I) is preferably a monocyclic aromatic hydrocarbon group, since this lowers the driving voltage of the light-emitting element of this embodiment, and more preferably a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from benzene, and these groups may have a substituent.

[0082] Ar b1 , Ar b2 and Ar b3 The heterocyclic group in the formula (I) is a monocyclic heterocyclic group or a polycyclic heterocyclic group, and these groups may have a substituent. Ar b1 , Arb2 and Ar b3 In the above, the monocyclic heterocyclic group is a monocyclic heterocyclic group. It is a group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting the ring from the compound, and the group may have a substituent.

[0083] Ar b1 , Ar b2 and Ar b3 In the above formula, the number of carbon atoms in the monocyclic heterocyclic group, not including the number of carbon atoms in the substituents, is preferably 1 to 20, more preferably 1 to 10, even more preferably 2 to 6, and particularly preferably 3 to 5. The number of heteroatoms in the monocyclic heterocyclic group, not including the number of heteroatoms in the substituents, is preferably 1 to 10, more preferably 1 to 5, even more preferably 1 to 3, and particularly preferably 1 or 2. Ar b1 , Ar b2 and Ar b3 In the above, the monocyclic heterocyclic compound in the monocyclic heterocyclic group is preferably furan, thiophene, pyrrole, triazole, pyridine, diazabenzene, or triazine, since the driving voltage of the light-emitting element of this embodiment is lower, more preferably furan, thiophene, pyrrole, triazole, pyridine, or diazabenzene, and even more preferably pyridine or diazabenzene.

[0084] Ar b1 , Ar b2 and Ar b3 In the formula (I), the polycyclic heterocyclic group is a group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting the ring from a polycyclic heterocyclic compound, and the group may have a substituent. Ar b1 , Ar b2 and Ar b3 In the above, the polycyclic heterocyclic compound in the polycyclic heterocyclic group may be a heterocyclic compound having a polycyclic heterocyclic skeleton (b') described later, or may be a heterocyclic compound not having a polycyclic heterocyclic skeleton (b') described later. b1 , Ar b2 and Arb3 In the formula (I), the polycyclic heterocyclic group may be the heterocyclic group (b') described below, or may be a heterocyclic group (Nb') obtained by removing one or more hydrogen atoms directly bonded to atoms constituting the ring from a heterocyclic compound not having a polycyclic heterocyclic skeleton (b').

[0085] The number of carbon atoms contained in the fused ring of the heterocyclic group (Nb'), not including the number of carbon atoms of the substituent, is usually 1 to 60, preferably 5 to 40, and more preferably 8 to 20. The number of heteroatoms contained in the fused ring of the heterocyclic group, not including the number of heteroatoms of the substituent, is usually 1 to 30, preferably 1 to 10, more preferably 1 to 5, even more preferably 1 to 3, and particularly preferably 1 or 2.

[0086] In the heterocyclic group (Nb'), the heterocyclic compound not having a heterocyclic skeleton (b') is not particularly limited as long as it is a heterocyclic compound not having a heterocyclic skeleton (b') as described below. A heterocyclic compound not having a polycyclic heterocyclic skeleton (b') lowers the driving voltage of the light-emitting device of this embodiment, and therefore is preferably a bicyclic to heptacyclic heterocyclic compound not having a heterocyclic skeleton (b'), more preferably a bicyclic to pentacyclic heterocyclic compound not having a heterocyclic skeleton (b'), even more preferably a bicyclic or tricyclic heterocyclic compound not having a heterocyclic skeleton (b'), and particularly preferably a tricyclic heterocyclic compound not having a heterocyclic skeleton (b'). Heterocyclic compounds not having a polycyclic heterocyclic skeleton (b') further reduce the driving voltage of the light-emitting device of this embodiment, and therefore are preferably azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, dibenzofuran, dibenzothiophene, dibenzoselenophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, acridone, azaanthracene, diazaanthracene, Azaphenanthrene or diazaphenanthrene is preferred, and azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, azaanthracene, diazaanthracene, azaphenanthrene, or diazaphenanthrene is more preferred, and azanaphthalene, diazanaphthalene, azaanthracene, diazaanthracene, azaphenanthrene, or diazaphenanthrene is particularly preferred.

[0087] The heterocyclic skeleton (b') is composed of a boron atom, a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and sp 3 and at least one selected from the group consisting of carbon atoms in a fused ring.

[0088] The number of carbon atoms contained in the fused ring of the heterocyclic skeleton (b') is usually 1 to 60, preferably 5 to 50, more preferably 10 to 40, and even more preferably 15 to 30, not including the number of carbon atoms of the substituent. The number of heteroatoms contained in the fused ring of the heterocyclic skeleton (b'), not including the number of heteroatoms of the substituents, is usually 2 to 30, preferably 2 to 15, more preferably 2 to 10, even more preferably 2 to 5, and particularly preferably 2 or 3. The number of boron atoms contained in the fused ring of the heterocyclic skeleton (b') is usually 1 to 10, preferably 1 to 5, more preferably 1 to 3, and even more preferably 1, not including the number of boron atoms in the substituents. The nitrogen atom, oxygen atom, sulfur atom, selenium atom and sp atom contained in the fused ring of the heterocyclic skeleton (b') 3 The total number of carbon atoms, not including the number of atoms of substituents, is usually 1 to 20, preferably 1 to 10, more preferably 1 to 5, still more preferably 1 to 3, and particularly preferably 2.

[0089] The heterocyclic skeleton (b') preferably contains a boron atom and at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, and a selenium atom in the ring, since this lowers the driving voltage of the light-emitting element of this embodiment; more preferably contains a boron atom and at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom in the ring; still more preferably contains a boron atom and at least one atom selected from the group consisting of a nitrogen atom and an oxygen atom in the ring; particularly preferably contains a boron atom and a nitrogen atom in the ring; and especially preferably contains a nitrogen atom that does not form a double bond with the boron atom in the ring.

[0090] The heterocyclic skeleton (b') is preferably a heterocyclic skeleton having two or more rings, more preferably a heterocyclic skeleton having three or more rings, even more preferably a heterocyclic skeleton having four or more rings, and particularly preferably a heterocyclic skeleton having five or more rings, since this lowers the driving voltage of the light-emitting device of this embodiment. Furthermore, the heterocyclic skeleton (b) may be, for example, a heterocyclic skeleton having 40 or fewer rings, or a heterocyclic skeleton having 30 or fewer rings. However, since this lowers the driving voltage of the light-emitting device of this embodiment, it is preferably a heterocyclic skeleton having 20 or fewer rings, more preferably a heterocyclic skeleton having 15 or fewer rings, even more preferably a heterocyclic skeleton having 10 or fewer rings, and particularly preferably a heterocyclic skeleton having 7 or fewer rings.

[0091] The heterocyclic skeleton (b') can also be referred to as a heterocyclic group (b') containing the heterocyclic skeleton (b'). Examples and preferred ranges of the substituents which the heterocyclic group (b') may have are the same as the examples and preferred ranges of the substituents which the heterocyclic group (b) may have.

[0092] Arb1 , Ar b2 and Ar b3 The heterocyclic group in the formula (I) is preferably a heterocyclic group (Nb') or a heterocyclic group (b'), and more preferably a heterocyclic group (b'), since the driving voltage of the light-emitting element of this embodiment is lowered. These groups may have a substituent.

[0093] Ar b1 , Ar b2 and Ar b3 is a monocyclic aromatic hydrocarbon group, a polycyclic aromatic hydrocarbon group, a monocyclic heterocyclic group, a heterocyclic group (Nb') or a heterocyclic group (b'), and is preferably a monocyclic aromatic hydrocarbon group, since the driving voltage of the light-emitting element of this embodiment is lowered. A group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic to pentacyclic aromatic hydrocarbon, a monocyclic heterocyclic group, a group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic to pentacyclic heterocyclic compound ring that does not have a heterocyclic skeleton (b'), or a heterocyclic group (b'), more preferably a monocyclic aromatic hydrocarbon group, a group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic or tricyclic aromatic hydrocarbon, a monocyclic heterocyclic group, a group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic or tricyclic heterocyclic compound ring that does not have a heterocyclic skeleton (b'), or Heterocyclic group (b'), more preferably a monocyclic aromatic hydrocarbon group, a monocyclic heterocyclic group, a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a bicyclic or tricyclic heterocyclic compound ring not having a heterocyclic skeleton (b'), or a heterocyclic group (b'), particularly preferably a monocyclic aromatic hydrocarbon group, a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a bicyclic or tricyclic heterocyclic compound ring not having a heterocyclic skeleton (b'), or a heterocyclic group (b'), and particularly preferably a monocyclic aromatic hydrocarbon group or a heterocyclic group (b'), and these groups may have a substituent. Ar b1 , Ar b2 and Ar b3The examples and preferred range of the substituents which may be possessed by the heterocyclic group (b) are the same as the examples and preferred range of the substituents which may be possessed by the heterocyclic group (b).

[0094] The low molecular weight compound (b) of this embodiment has a hexacyclic or higher heterocyclic skeleton (b), which reduces the driving voltage of the light-emitting device of this embodiment. Therefore, when formula (b0) satisfies at least one of requirements (b0-i) and (b0-ii), the low molecular weight compound having a heterocyclic skeleton represented by formula (b0) has a hexacyclic or higher heterocyclic skeleton (b), which reduces the driving voltage of the light-emitting device of this embodiment.

[0095] If formula (b0) satisfies requirement (b0-i), then Ar b1 , Ar b2 and Ar b3 At least one of the above is a polycyclic aromatic hydrocarbon group or a polycyclic heterocyclic group, and is preferably a polycyclic heterocyclic group because the driving voltage of the light-emitting element of this embodiment is lower. More preferably, it is a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a bicyclic to pentacyclic heterocyclic compound ring that does not have a heterocyclic skeleton (b'), or a heterocyclic group (b'). Even more preferably, it is a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a bicyclic or tricyclic heterocyclic compound ring that does not have a heterocyclic skeleton (b'), or a heterocyclic group (b'). Particularly preferably, it is a heterocyclic group (b'). These groups may have a substituent.

[0096] When the formula (b0) satisfies the requirement (b0-i), the driving voltage of the light-emitting device of this embodiment becomes lower, so that Ar b1 , Ar b2 and Ar b3 At least one of the groups (a) and (b) is preferably a polycyclic heterocyclic group, more preferably a heterocyclic group (b'), and these groups may have a substituent.

[0097] When formula (b0) satisfies the requirement (b0-i), the driving voltage of the light-emitting device of this embodiment is lowered, and therefore, preferably, Ar b1and Ar b2 At least one of Ar is a polycyclic aromatic hydrocarbon group or a polycyclic heterocyclic group (preferably a polycyclic heterocyclic group), b2 is more preferably a polycyclic aromatic hydrocarbon group or a polycyclic heterocyclic group (preferably a polycyclic heterocyclic group), and Ar b2 is more preferably a heterocyclic group (b'), and these groups may have a substituent.

[0098] Formula (b0) satisfies requirement (b0-i) and Ar b1 , Ar b2 and Ar b3 is other than the heterocyclic group (b'), Ar b1 , Ar b2 and Ar b3 Examples and preferred ranges of Ar are described later. b , Ar b4 and Ar b5 The examples and preferred ranges are the same as those of the above.

[0099] When the formula (b0) satisfies the requirement (b0-i), the heterocyclic group (b') is Since the driving voltage of the element is lower, the groups represented by formulae (b1'-1) to (b1'-4) are preferred, the groups represented by formula (b1'-2) or (b1'-3) are more preferred, and the group represented by formula (b1'-2) is even more preferred.

[0100] [ka] [In the formula, R xb has the same meaning as above. Ar b , Ar b4 and Ar b5 each independently represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Xb3 , X b4 and X b5 are each independently an oxygen atom, a sulfur atom, a selenium atom, -N(R xb )-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. n b1’ represents 2 or 3. However, Ar b1 When is a group represented by formula (b1'-1) to formula (b1'-4), n b1’ represents 3. Ar b2 or Ar b3 When is a group represented by formula (b1'-1) to formula (b1'-4), n b1’ represents 2. * b1’ represents the bond position. b1 When the group is represented by formula (b1'-1) to formula (b1'-4), three * b1’ are, respectively, X b1 , X b2 and a bond with a boron atom. b2 When is a group represented by formula (b1'-1) to formula (b1'-4), two * b1’ are, respectively, X b1 and a bond with a boron atom. b3 When is a group represented by formula (b1'-1) to formula (b1'-4), two * b1’ are, respectively, X b2 and a bond with a boron atom. X b3 and Ar b , X b3 and Ar b4 , X b4 and Ar b4 , X b4 and Ar b5 , X b5 and Ar b5 , and X b5 and Ar bmay each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring, and in formula (b1'-1) and formula (b1'-3), Ar b4 and Ar b5 may be bonded directly or via a divalent or higher valent group which may have a substituent to form a ring, and in formula (b1'-1) and formula (b1'-2), Ar b and Ar b5 and may be bonded directly or via a divalent or higher group which may have a substituent to form a ring. When there are multiple substituents in the above group, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded.

[0101] Ar b , Ar b4 and Ar b5 Examples of the aromatic hydrocarbon group and preferred ranges thereof are Ar b1 , Ar b2 and Ar b3 The examples and preferred ranges of the aromatic hydrocarbon group are the same as those in the above. Ar b , Ar b4 and Ar b5 Examples and preferred ranges of the heterocyclic group in b1 , Ar b2 and Ar b3 The examples and preferred ranges of the heterocyclic group are the same as those in Ar b , Ar b4 and Ar b5 The heterocyclic group in (b) is preferably a monocyclic heterocyclic group or a heterocyclic group (Nb'), more preferably a monocyclic heterocyclic group, because it reduces the driving voltage of the light-emitting element of this embodiment and facilitates the synthesis of a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0), and these groups may have a substituent.

[0102] Ar b , Ar b4 and Ar b5is preferably an aromatic hydrocarbon group which may have a substituent, since this reduces the driving voltage of the light-emitting element of this embodiment and makes it easy to synthesize a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0).

[0103] Ar b , Ar b4 and Ar b5 is preferably a monocyclic aromatic hydrocarbon group, a polycyclic monocyclic heterocyclic group, a monocyclic heterocyclic group, or a heterocyclic group (Nb'), because this further reduces the driving voltage of the light-emitting device of this embodiment and facilitates the synthesis of a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0), and more preferably a monocyclic aromatic hydrocarbon group, a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a bicyclic to pentacyclic aromatic hydrocarbon, a monocyclic heterocyclic group, or a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from a bicyclic to pentacyclic heterocyclic compound ring not having a heterocyclic skeleton (b'), and further Preferably, it is a monocyclic aromatic hydrocarbon group, a group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic or tricyclic aromatic hydrocarbon, a monocyclic heterocyclic group, or a group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic or tricyclic heterocyclic compound ring that does not have a heterocyclic skeleton (b'), and particularly preferably, it is a monocyclic aromatic hydrocarbon group, or a group in which one or more hydrogen atoms directly bonded to an atom constituting the ring have been removed from a bicyclic or tricyclic aromatic hydrocarbon, and particularly preferably, it is a monocyclic aromatic hydrocarbon group, and these groups may have a substituent. Ar b , Ar b4 and Ar b5 Examples of the substituents that may be possessed by Ar and the preferred range thereof are as follows: b1 , Ar b2 and Ar b3 The examples and preferred ranges of the substituents that may be possessed by the group are the same as those of the substituents that may be possessed by the group.

[0104] X b3 , X b4 and X b5 Examples and preferred ranges of X b1 and Xb2 The examples and preferred ranges are the same as those of the above. Examples and preferred ranges of the divalent or more groups which may have a substituent in formulas (b1'-1) to (b1'-4) are the same as the examples and preferred ranges of the divalent or more groups which may have a substituent described later in the section regarding the case where formula (b0) satisfies requirement (b0-ii).

[0105] When formula (b0) satisfies requirement (b0-i), a low molecular weight compound having a heterocyclic skeleton represented by formula (b0) reduces the driving voltage of the light-emitting element of this embodiment. Therefore, the low molecular weight compound is preferably a low molecular weight compound having a heterocyclic skeleton represented by formulas (b0-1-1) to (b0-1-3) (i.e., the heterocyclic skeleton represented by formula (b0) is the heterocyclic skeleton represented by formulas (b0-1-1) to (b0-1-3)), and more preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) (i.e., the heterocyclic skeleton represented by formula (b0) is the heterocyclic skeleton represented by formula (b0-1-1)).

[0106] [ka] [In the formula, Ar b , Ar b1 , Ar b2 , Ar b3 , Ar b4 , Ar b5 , X b1 , X b2 , X b3 , X b4 and X b5 has the same meaning as above.]

[0107] In formulas (b0-1-1) to (b0-1-3), Ar b1 , Ar b2 and Ar b3 is other than the heterocyclic group (b'), Ar b1 , Ar b2 and Ar b3 Examples and preferred ranges of Ar b , Ar b4 and Ar b5 The examples and preferred ranges are the same as those of the above.

[0108] Formula (b0) satisfies requirement (b0-ii) and Ar b1 , Ar b2 and Ar b3 is other than the heterocyclic group (b'), Ar b1 , Ar b2 and Ar b3 Examples and preferred ranges of Ar b , Ar b4 and Ar b5 The examples and preferred ranges are the same as those of the above.

[0109] When the formula (b0) satisfies the requirement (b0-ii), the driving voltage of the light-emitting device of this embodiment becomes lower, so that X b1 and Ar b1 , X b1 and Ar b2 , X b2 and Ar b1 , and X b2 and Ar b3 Preferably, at least one of the following is bonded directly or via a divalent or higher valent group which may have a substituent to form a ring; and X b1 and Ar b2 , and X b2 and Ar b3 It is more preferable that at least one of the following is bonded directly or via a divalent or higher group which may have a substituent to form a ring; and X b2 and Ar b3 However, it is more preferable that they are bonded directly or via a divalent or higher valent group which may have a substituent to form a ring.

[0110] When formula (b0) satisfies requirement (b0-ii), the divalent or higher valent group is preferably a divalent to tetravalent group, more preferably a divalent or trivalent group, because this reduces the driving voltage of the light-emitting element of this embodiment and facilitates the synthesis of a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0), and these groups may have a substituent.

[0111] When formula (b0) satisfies requirement (b0-ii), the divalent group is preferably an alkylene group, a cycloalkylene group, or -N(R 0 )-, -B(R 0 )-, a group represented by -O-, a group represented by -S-, or a group represented by -Se-, and more preferably an alkylene group, -N(R 0 )-, -B(R 0 )-, -O-, -S- or -Se-, and more preferably -N(R 0 )-, -B(R 0 )-, -O-, -S- or -Se-, and particularly preferably -N(R 0 )-, -B(R 0 )-, -O-, or -S-, and particularly preferably -N(R 0 )-, -B(R 0 )- or -O-, and these groups may have a substituent.

[0112] When formula (b0) satisfies requirement (b0-ii), the trivalent group is preferably a group in which one hydrogen atom has been removed from an alkylene group, a group in which one hydrogen atom has been removed from a cycloalkylene group, or a group represented by formula (Xb0-1), because this reduces the driving voltage of the light-emitting element of this embodiment and facilitates the synthesis of a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0), more preferably a group in which one hydrogen atom has been removed from an alkylene group or a group represented by formula (Xb0-1), and even more preferably a group represented by formula (Xb0-1), and these groups may have a substituent.

[0113] [ka] [In the formula, X b0-1is a boron atom, a nitrogen atom, a phosphorus atom, P(=O), Si(R 0 ) or Ge(R 0 ) represents.

[0114] X b0-1 is preferably a boron atom, a nitrogen atom, a phosphorus atom, or P(═O), more preferably a boron atom or a nitrogen atom, and even more preferably a boron atom, since this lowers the driving voltage of the light-emitting element of this embodiment.

[0115] When formula (b0) satisfies requirement (b0-ii), the tetravalent group is preferably a group in which two hydrogen atoms have been removed from an alkylene group, a group in which two hydrogen atoms have been removed from a cycloalkylene group, or a group represented by formula (Xb0-2), because this reduces the driving voltage of the light-emitting element of this embodiment and facilitates the synthesis of a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0), and more preferably a group in which two hydrogen atoms have been removed from an alkylene group or a group represented by formula (Xb0-2), and these groups may have a substituent.

[0116] [ka] [In the formula, X b0-2 represents a silicon atom or a germanium atom.

[0117] R in a divalent or higher group when formula (b0) satisfies requirement (b0-ii) 0 Examples and preferred ranges of R xb In the divalent or higher valent group in the case where formula (b0) satisfies requirement (b0-ii), examples and preferred ranges of the alkylene group and cycloalkylene group are the same as those of X b1 and X b2 When formula (b0) satisfies requirement (b0-ii), examples and preferred ranges of the substituents that the divalent or higher group may have are the same as the examples and preferred ranges of the substituents that the heterocyclic group (b) may have.

[0118] When formula (b0) satisfies requirement (b0-ii), a compound having a heterocyclic skeleton represented by formula (b0) is Since the driving voltage of the light-emitting device of this embodiment is lowered by using such a low-molecular-weight compound, the low-molecular-weight compound is preferably a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0-2-1) to formula (b0-2-4) (i.e., the heterocyclic skeleton represented by formula (b0) is a heterocyclic skeleton represented by formula (b0-2-1) to formula (b0-2-4)), more preferably a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0-2-1) or formula (b0-2-3) (i.e., the heterocyclic skeleton represented by formula (b0) is a heterocyclic skeleton represented by formula (b0-2-1) or formula (b0-2-3)), and even more preferably a low-molecular-weight compound having a heterocyclic skeleton represented by formula (b0-2-1) (i.e., the heterocyclic skeleton represented by formula (b0) is a heterocyclic skeleton represented by formula (b0-2-1)).

[0119] [ka] [In the formula, Ar b1 , Ar b2 , Ar b3 and X b2 has the same meaning as above. Ar xb1 and Ar xb2 each independently represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X xb1 , X xb2 and X xb3 are each independently a direct bond, an oxygen atom, a sulfur atom, a selenium atom, or -N(R xb )-, -B(R xb )-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. R xb represents the same meaning as above. X xb1 and Ar xb1 , X xb1 and Ar b2 , X xb2 and Ar xb1 , X xb2 and Ar b1 , X xb3 and Ar xb2 , and X xb3 and Ar b3 may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring, and in formula (b0-2-1) and formula (b0-2-3), Ar b1 and Ar xb1 may be bonded directly or via a divalent or higher valent group which may have a substituent to form a ring, and in formula (b0-2-2) and formula (b0-2-4), Ar b2 and Ar xb1 may be bonded directly or via a divalent or higher valent group which may have a substituent to form a ring, and in formula (b0-2-3) and formula (b0-2-4), Ar b1 and Ar xb2 may be bonded directly or via a divalent or higher group which may have a substituent to form a ring. When there are multiple substituents in the divalent or higher group, they may be the same or different and may be bonded to each other to form a ring together with the atom to which they are bonded.

[0120] Ar xb1 and Ar xb2 Examples and preferred ranges of Ar b , Ar b4 and Ar b5 The examples and preferred ranges are the same as those of the above.

[0121] In formulas (b0-1-1) to (b0-1-3), Ar b1 , Ar b2 and Ar b3 is other than the heterocyclic group (b'), Ar b1 , Ar b2 and Ar b3Examples and preferred ranges of Ar b , Ar b4 and Ar b5 The examples and preferred ranges are the same as those of the above.

[0122] X xb1 , X xb2 and X xb3 is preferably a direct bond, an oxygen atom, a sulfur atom, a selenium atom, or —N(R xb )- or -B(R xb )-, and more preferably a direct bond, an oxygen atom, a sulfur atom, or —N(R xb )- or -B(R xb )-, and more preferably a direct bond, an oxygen atom, or —N(R xb )- or -B(R xb )-, and particularly preferably, -N(R xb )- or -B(R xb )-, and particularly preferably -B(R xb )-, and these groups may have a substituent. X xb1 , X xb2 and X xb3 Examples of the substituents that may be possessed by X and the preferred range thereof are as follows: b1 and X b2 The examples and preferred ranges of the substituents that may be possessed by the group are the same as those of the substituents that may be possessed by the group.

[0123] Examples and preferred ranges of the divalent or higher valent groups which may have a substituent in formulas (b0-2-1) to (b0-2-4) are the same as the examples and preferred ranges of the divalent or higher valent groups which may have a substituent described in the section when formula (b0) satisfies requirement (b0-ii).

[0124] The low molecular weight compound (b) is preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) to formula (b0-1-3) or formula (b0-2-1) to formula (b0-2-4), more preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1), formula (b0-1-2), formula (b0-2-1) or formula (b0-2-3), still more preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1), formula (b0-2-1) or formula (b0-2-3), and particularly preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1).

[0125] The low molecular weight compound having a heterocyclic skeleton represented by formula (b0) preferably satisfies at least one of requirement (i) and requirement (ii), and more preferably satisfies both requirement (i) and requirement (ii), because the driving voltage of the light-emitting device of this embodiment is lower.

[0126] When the low molecular weight compound (b) satisfies the requirement (i), the driving voltage of the light-emitting device of this embodiment is lowered. Therefore, the low molecular weight compound (b) is preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) to formula (b0-1-3) or formula (b0-2-1) to formula (b0-2-4), more preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) to formula (b0-1-3), formula (b0-2-1) or formula (b0-2-3), even more preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) to formula (b0-1-3), particularly preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) or formula (b0-1-2), and especially preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1).

[0127] When the low molecular weight compound (b) satisfies the requirement (ii), the driving voltage of the light emitting device of this embodiment becomes lower. Therefore, in the formulas (b0-1-1) and (b0-1-2), X b1 , X b2 , X b3 and X b4At least two of the following are -N(R xb When the low molecular weight compound (b) satisfies the requirement (ii), X in the formula (b0-1-3) is preferably a group represented by the formula (b0-1-3). b1 , X b2 , X b3 and X b5 At least two of the following are -N(R xb When the low molecular weight compound (b) satisfies the requirement (ii), X in formula (b0-2-1) is preferably a group represented by the formula (b0-2-2). xb1 and X b2 At least one of -N(R xb When the low molecular weight compound (b) satisfies the requirement (ii), X in the formula (b0-2-2) is preferably a group represented by the formula (b0-2-3). xb2 and X b2 At least one of -N(R xb )- is preferably a group represented by the formula:

[0128] When the low molecular weight compound (b) satisfies the requirements (i) and (ii), the driving voltage of the light-emitting device of this embodiment becomes lower. Therefore, the low molecular weight compound (b) is preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1) or formula (b0-1-2), and in formula (b0-1-1) and formula (b0-1-2), X b1 , X b2 , X b3 and X b4 At least two of the following are -N(R xb It is preferable that the compound is a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1), and in formula (b0-1-1), X b1 , X b2 , X b3 and X b4 At least two of the following are -N(R xb It is more preferable that the compound is a low molecular weight compound represented by the group represented by the formula (I).

[0129] A low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1), wherein X b1 , X b2 , Xb3 and X b4 At least two of the following are -N(R xb The low molecular weight compound which is a group represented by formula (b0-1-1′)- may be, for example, a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1′).

[0130] [ka] [In the formula, Ar b , Ar b1 , Ar b3 , Ar xb1 , Ar b4 , Ar b5 , X b2 , X b4 and X b0-1 represents the same meaning as above. Ar xb3 represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar b1 and Ar xb1 , Ar xb1 and Ar xb3 , and Ar xb3 and Ar b4 may each independently bond directly or via a divalent or higher group which may have a substituent to form a ring. When there are multiple substituents in the divalent or higher group, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded.

[0131] Ar xb3 Examples and preferred ranges of Ar xb1 and Ar xb2 The examples and preferred ranges are the same as those of the above.

[0132] Examples and preferred ranges of the divalent or higher valent group which may have a substituent in formula (b0-1-1') are the same as the examples and preferred ranges of the divalent or higher valent group which may have a substituent described in the section when formula (b0) satisfies requirement (b0-ii).

[0133] (Low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1)) As described above, the low molecular weight compound (b) preferably satisfies the requirement (i), and is more preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b0-1-1). However, since the driving voltage of the light-emitting device of this embodiment is further reduced, it is preferable to use a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1). It is more preferable that the compound is a low molecular weight compound having a high molecular weight. As described above, it is preferable that the low molecular weight compound (b) further satisfies the requirement (ii), and the driving voltage of the light-emitting device of this embodiment is further reduced. Therefore, in the formula (b1-1), X b1 , X b2 , X b3 and X b4 At least two of the following are -N(R xb )- is preferably a group represented by the formula:

[0134] Ring R in formula (b1-1) b1 , ring R b2 and ring R b3 Examples and preferred ranges of the aromatic hydrocarbon ring and heterocyclic ring in b1 , Ar b2 and Ar b3 The examples and preferred ranges of the aromatic hydrocarbon ring and heterocyclic ring are the same as those explained in the section on aromatic hydrocarbon groups and heterocyclic groups in the above. Ring R in formula (b1-1) b4 and ring R b5 Examples and preferred ranges of the aromatic hydrocarbon ring and heterocyclic ring in b4 and Ar b5 The examples and preferred ranges of the aromatic hydrocarbon ring and heterocyclic ring are the same as those explained in the section on aromatic hydrocarbon groups and heterocyclic groups in the above. Ring R b1 , ring R b2 , ring Rb3 , ring R b4 and ring R b5 Examples of the substituents that may be possessed by Ar and the preferred range thereof are as follows: b1 , Ar b2 and Ar b3 The examples and preferred ranges of the substituents that may be possessed by the group are the same as those of the substituents that may be possessed by the group. Ring R b1 , ring R b2 , ring R b3 , ring R b4 and ring R b5 Since it has one or more bonds, the ring R b1 , ring R b2 , ring R b3 , ring R b4 and ring R b5 The aromatic hydrocarbon ring and heterocyclic ring in the formula (I) can also be referred to as an aromatic hydrocarbon group and a heterocyclic group, respectively.

[0135] Therefore, the ring R b1 , ring R b2 , ring R b3 , ring R b4 and ring R b5 Examples and preferred ranges of Ar in formula (b1-1) are b1 , Ar b , Ar b3 , Ar b4 and Ar b5 Similarly, the examples and preferred ranges of X in formula (b1-1) can be applied. b1 , X b2 , X b3 and X b4 The examples and preferred ranges of X are described in the section on formula (b0). b1 , X b2 , X b3 and X b4 Similarly, the examples and preferred ranges of the divalent or more optionally substituted group in formula (b1-1) are the same as the examples and preferred ranges of the divalent or more optionally substituted group described in the section on the case where formula (b0) satisfies requirement (b0-ii).

[0136] Ring R b1 , ring Rb2 , ring R b3 , ring R b4 and ring R b5 is preferably an aromatic hydrocarbon ring, more preferably a monocyclic aromatic hydrocarbon ring, and even more preferably a benzene ring, since this reduces the driving voltage of the light-emitting element of this embodiment, and these rings may have a substituent.

[0137] As explained in the section on the low molecular weight compound (b) above, the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) lowers the driving voltage of the light emitting device of this embodiment, so the sp 3 The total number of carbon atoms is preferably 9 or more. Furthermore, since the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) further reduces the driving voltage of the light emitting device of this embodiment, it is preferable that the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. Since the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) further reduces the driving voltage of the light emitting device of this embodiment, it is preferable that the sp 3 It is preferable that the low molecular weight compound having a total of 9 or more carbon atoms and a heterocyclic skeleton represented by formula (b1-1) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents.

[0138] The low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) may be, for example, a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2-0).

[0139] [ka] [In the formula, Ring R b1 , ring R b2 , ring Rb3 , ring R b4 , ring R b5 , X b2 , X b4 and X b0-1 represents the same meaning as above. Ring R Xb1 and ring R Xb2 each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ring R Xb1 and ring R b1 , ring R Xb1 and ring R Xb2 , and ring R Xb2 and ring R b4 may each independently bond directly or via a divalent or higher group which may have a substituent to form a ring. When there are multiple substituents in the divalent or higher group, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded.

[0140] Ring R Xb1 and ring R Xb2 Examples and preferred ranges of the ring R b1 , ring R b2 , ring R b3 , ring R b4 and ring R b5 The examples and preferred ranges are the same as those of the above. Examples and preferred ranges of the optionally substituted divalent or higher valent group in formula (b1-2-0) are the same as the examples and preferred ranges of the optionally substituted divalent or higher valent group in formula (b1-1).

[0141] The low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2-0) further reduces the driving voltage of the light-emitting element of this embodiment, and is therefore preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2).

[0142] (Low molecular weight compound represented by formula (b1-1')) As described above in the section on the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1), the driving voltage of the light-emitting device of this embodiment is lowered. Therefore, the sp 3 Preferably, the total number of carbon atoms is 9 or more, or the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. That is, the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) is preferably a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1').

[0143] In the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1'), the sp 3 The total number of carbon atoms is 9 or more, or the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents. Examples and preferred ranges of these are the same as the examples and preferred ranges described above in the section on low molecular weight compound (b). The low molecular weight compound represented by formula (b1-1') may be, for example, a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2').

[0144] Examples of the low molecular weight compound (b) include low molecular weight compounds represented by the following formula: 1 represents an oxygen atom or a sulfur atom. 1 When a plurality of Z are present, they may be the same or different. 2 represents a group represented by -CH= or -N=. Z 2 When there are multiple Z's, they may be the same or different. 3 represents a hydrogen atom or an alkyl group. 3 When there are multiple groups, they may be the same or different.

[0145]

change

[0146]

change

[0147]

change

[0148]

change

[0149]

change

[0150]

change

[0151]

change

[0152]

change

[0153] The maximum peak wavelength of the emission spectrum of the low molecular weight compound (b) at 25°C is preferably 380 nm or more, more preferably 400 nm or more, even more preferably 420 nm or more, particularly preferably 440 nm or more, especially preferably 460 nm or more, and may be 480 nm or more, 500 nm or more, 510 nm or more, 520 nm or more, or 525 nm or more. The maximum peak wavelength of the emission spectrum of the low molecular weight compound (b) at 25°C is preferably 750 nm or less, more preferably 620 nm or less, and even more preferably 570 nm or less.

[0154] The half width of the maximum peak in the emission spectrum of low molecular weight compound (b) at 25°C may be 1 nm or more, 3 nm or more, 5 nm or more, 7 nm or more, or 10 nm or more. The half width of the maximum peak in the emission spectrum of low molecular weight compound (b) at 25°C is preferably 50 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less, particularly preferably 25 nm or less, especially preferably 20 nm or less, especially more preferably 19 nm or less, and may be 18 nm or less, 15 nm or less, or 14 nm or less. The maximum peak wavelength of the emission spectrum of a compound at room temperature was measured by dissolving the compound in an organic solvent such as xylene, toluene, chloroform, or tetrahydrofuran to prepare a dilute solution (1 × 10 -6 Mass%~1×10 -3 % by mass), the PL spectrum of the diluted solution can be measured at room temperature. Xylene or toluene is preferred as the organic solvent for dissolving the compound.

[0155] [High molecular compound (H)] The polymer compound (H) is preferably a polymer compound containing at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y), because this lowers the driving voltage of the light-emitting device of this embodiment.

[0156] The polymer compound (H) preferably contains a structural unit represented by formula (Y), since this leads to a lower driving voltage of the light-emitting device of this embodiment. When the polymer compound (H) contains a structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) contained in the polymer compound (H) may be within a range that allows the polymer compound (H) to function as the polymer compound (H). When the polymer compound (H) contains a structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) contained in the polymer compound (H) is, for example, 1 to 100 mol % relative to the total content of structural units contained in the polymer compound (H). Since this further reduces the driving voltage of the light-emitting device of this embodiment, the content is preferably 10 to 100 mol %, more preferably 30 to 100 mol %, even more preferably 50 to 100 mol %, particularly preferably 70 to 100 mol %, and particularly preferably 90 to 100 mol %. In the polymer compound (H), the structural unit represented by formula (Y) may be contained in the polymer compound (H) in one type or in two or more types.

[0157] The polymer compound (H) preferably contains a structural unit represented by formula (X), since this provides the polymer compound (H) with excellent hole transport properties and lowers the driving voltage of the light-emitting device of this embodiment. When the polymer compound (H) contains a structural unit represented by formula (X), the content of the structural unit represented by formula (X) contained in the polymer compound (H) may be within a range that allows the polymer compound (H) to exhibit its functions. When the polymer compound (H) contains a structural unit represented by formula (X), the content of the structural unit represented by formula (X) contained in the polymer compound (H) is, for example, 0.01 to 100 mol % relative to the total content of structural units contained in the polymer compound (H). Since the hole transport properties of the polymer compound (H) are excellent and the driving voltage of the light-emitting device of this embodiment is further reduced, the content is preferably 0.1 to 90 mol %, more preferably 0.2 to 70 mol %, even more preferably 0.5 to 50 mol %, particularly preferably 1 to 30 mol %, and particularly preferably 2 to 10 mol %. In the polymer compound (H), the structural unit represented by formula (X) may be contained in only one type, or in two or more types.

[0158] The polymer compound (H) preferably contains a structural unit represented by formula (Y) and a structural unit represented by formula (X), because this provides the polymer compound (H) with excellent hole transport properties and further reduces the driving voltage of the light-emitting device of this embodiment. When the polymer compound (H) contains a structural unit represented by formula (Y) and a structural unit represented by formula (X), the total content of the structural unit represented by formula (Y) and the structural unit represented by formula (X) contained in the polymer compound (H) may be within a range that allows the polymer compound (H) to function. When the polymer compound (H) contains a structural unit represented by formula (Y) and a structural unit represented by formula (X), the total content of the structural unit represented by formula (Y) and the structural unit represented by formula (X) contained in the polymer compound (H) is, for example, 1 to 100 mol%, and is preferably 10 to 100 mol%, more preferably 30 to 100 mol%, even more preferably 50 to 100 mol%, particularly preferably 70 to 100 mol%, and particularly preferably 90 to 100 mol%, because this provides excellent hole transport properties for the polymer compound (H) and further reduces the driving voltage of the light-emitting device of this embodiment.

[0159] (Constituent unit represented by formula (Y)) Ar Y1The arylene group represented by the formula (I) is preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon, since this reduces the driving voltage of the light-emitting device of this embodiment; more preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon; even more preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, dibenzocycloheptane or fluorene; particularly preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from benzene, phenanthrene, dihydrophenanthrene or fluorene; and particularly preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from benzene or fluorene, and these groups may have a substituent.

[0160] Ar Y1The divalent heterocyclic group represented by the formula (I) is preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from a monocyclic or bicyclic to hexacyclic heterocyclic compound, more preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from a monocyclic, bicyclic or tricyclic heterocyclic compound, and even more preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine, because the driving voltage of the light-emitting element of this embodiment is lower. and particularly preferably a group obtained by removing two hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom, more preferably a carbon atom) from pyridine, diazabenzene, triazine, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, or phenothiazine, and particularly preferably a group obtained by removing two hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom, more preferably a carbon atom) from pyridine, diazabenzene, triazine, carbazole, dibenzofuran, or dibenzothiophene, and these groups may have a substituent. Ar Y1 In the divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded, the preferred ranges of the arylene group and the divalent heterocyclic group are, respectively, Ar Y1 The preferred ranges are the same as those of the arylene group and divalent heterocyclic group represented by the following formula:

[0161] Ar Y1 In the above, examples of the "divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded" include groups represented by the following formula: These groups may have a substituent.

[0162] [ka]

[0163] Ar Y1 is preferably an arylene group which may have a substituent, since this leads to a lower driving voltage of the light-emitting device of this embodiment.

[0164] Ar Y1 The substituent that the group represented by the formula (I) may have is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group, or a fluorine atom, since this reduces the driving voltage of the light-emitting element of this embodiment, more preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, even more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, and particularly preferably an alkyl group, a cycloalkyl group, or an aryl group, and these groups may further have a substituent. Ar Y1 The aryl group in the substituent that may be contained in the group represented by the formula (I) is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon, more preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, even more preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, dibenzocycloheptane or fluorene, particularly preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from benzene, phenanthrene, dihydrophenanthrene or fluorene, and particularly preferably a phenyl group, and these groups may further contain a substituent. Ar Y1The monovalent heterocyclic group in the substituent that may be included in the group represented by the formula (I) is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic or bicyclic to hexacyclic heterocyclic compound, more preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring has been removed from a monocyclic, bicyclic or tricyclic heterocyclic compound, and even more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine, or It is a group obtained by removing, from 5,10-dihydrophenazine, one hydrogen atom that is directly bonded to an atom that constitutes the ring (preferably a carbon atom or a nitrogen atom), and is particularly preferably a group obtained by removing, from pyridine, diazabenzene, triazine, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, or phenothiazine, one hydrogen atom that is directly bonded to an atom that constitutes the ring (preferably a carbon atom or a nitrogen atom), and is particularly preferably a group obtained by removing, from pyridine, diazabenzene, or triazine, one hydrogen atom that is directly bonded to an atom that constitutes the ring (preferably a carbon atom), and these groups may further have a substituent. Ar Y1 In the substituted amino group in the substituent that may be possessed by the group represented by the formula: the substituent possessed by the amino group is preferably an aryl group or a monovalent heterocyclic group, and more preferably an aryl group. These groups may further have a substituent. Examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituent of the amino group are Ar Y1 The examples and preferred ranges of the aryl group and monovalent heterocyclic group in the substituent that may be possessed by the group represented by the following formula are the same as those of the aryl group and monovalent heterocyclic group.

[0165] Ar Y1The substituent that the group represented by the formula (I) may further have is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group, or a fluorine atom, because this reduces the driving voltage of the light-emitting element of this embodiment. More preferably, it is an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, or a substituted amino group. Even more preferably, it is an alkyl group, a cycloalkyl group, or an aryl group. Particularly preferably, it is an alkyl group or a cycloalkyl group. These groups may further have a substituent, but it is preferable that they do not have a further substituent. Ar Y1 Examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that may be further substituted by the substituent that may be substituted by the group represented by the formula: Y1 The examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the group represented by the following formula may have are the same as those of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the group represented by the following formula may have.

[0166] The structural unit represented by formula (Y) is preferably a structural unit represented by formula (Y-1) to formula (Y-9), since it lowers the driving voltage of the light-emitting device of this embodiment, and more preferably a structural unit represented by formula (Y-1), formula (Y-3), formula (Y-5), formula (Y-6) or formula (Y-7).

[0167] [ka]

[0168] [ka]

[0169] [ka]

[0170] [ka] [In the formula, X Y1 is -C(R Y2 )2-, -C(R Y2 )=C(R Y2 )-, -C(R Y2 )2-C(R Y2 )2-, -C(R Y1 )2-C(R Y1 )2-C(R Y1 )2-, -O-, -S-, or -N(R Y4 )-. R Y1 , R Y2 , R Y3 and R Y4 are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group, or a fluorine atom, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When there are multiple R Y1 , multiple R Y2 They may be the same or different and may be bonded to each other to form a ring together with the carbon atoms to which they are bonded.

[0171] R Y1 is preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, since this reduces the driving voltage of the light-emitting element of this embodiment, more preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, even more preferably a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group, and particularly preferably a hydrogen atom or an alkyl group, and these groups may have a substituent. R Y2is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, since this reduces the driving voltage of the light-emitting element of this embodiment, more preferably an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and even more preferably an alkyl group, a cycloalkyl group, or an aryl group, and these groups may have a substituent.

[0172] R Y3 is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a cycloalkyl group, because it lowers the driving voltage of the light-emitting element of this embodiment. The heterocyclic group is preferably a cyclic group or a substituted amino group, more preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, still more preferably an aryl group or a monovalent heterocyclic group, and particularly preferably an aryl group, and these groups may have a substituent. R Y4 is preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, since this reduces the driving voltage of the light-emitting element of this embodiment, more preferably an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, even more preferably an aryl group or a monovalent heterocyclic group, and particularly preferably an aryl group, and these groups may have a substituent.

[0173] R Y1 , R Y2 , R Y3 and R Y4 Examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in Y1 The examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the group represented by the following formula may have are the same as those of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the group represented by the following formula may have. R Y1 , R Y2 , R Y3 and R Y4 Examples of the substituents that may be possessed by Ar and the preferred range thereof are as follows: Y1The examples and preferred ranges of the substituents that may be possessed by the group represented by the formula:

[0174] X Y1 is preferably -C(R Y2 )2-, -C(R Y2 )2-C(R Y2 )2-, -C(R Y1 )2-C(R Y1 )2-C(R Y1 )2-, -O-, or -S-, and -C(R Y2 )2-, -C(R Y2 )2-C(R Y2 )2-, -O-, -S-, or -N(R Y4 )-, and more preferably, -C(R Y2 )2-, -O-, or -S-, and particularly preferably -C(R Y2 )2- or -S-.

[0175] Examples of the constitutional unit represented by formula (Y) include constitutional units represented by the following formula:

[0176] [ka]

[0177] [ka]

[0178] [ka]

[0179] [ka]

[0180] [ka]

[0181] [ka]

[0182] [ka]

[0183] [ka]

[0184] [ka]

[0185] [ka]

[0186] [ka]

[0187] [ka]

[0188] [ka]

[0189] (Constituent unit represented by formula (X)) a X1 and a X2 is usually an integer of 0 to 10, and is preferably an integer of 0 to 5, more preferably an integer of 0 to 3, even more preferably an integer of 0 to 2, and particularly preferably 0 or 1, since the driving voltage of the light-emitting element of this embodiment becomes lower.

[0190] RX1 , R X2 and R X3 is preferably an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, more preferably an aryl group or a monovalent heterocyclic group, and even more preferably an aryl group, since this results in a lower driving voltage for the light-emitting element of this embodiment, and these groups may have a substituent. R X1 , R X2 and R X3 Examples and preferred ranges of the aryl group and the monovalent heterocyclic group in Y1 The examples and preferred ranges of the aryl group and monovalent heterocyclic group in the substituent that may be possessed by the group represented by the following formula are the same as those of the aryl group and monovalent heterocyclic group.

[0191] Ar X1 , Ar X2 , Ar X3 and Ar X4 is preferably an arylene group which may have a substituent, since the driving voltage of the light-emitting device of this embodiment is lowered. Ar X1 , Ar X2 , Ar X3 and Ar X4 Examples and preferred ranges of the arylene group and the divalent heterocyclic group in Y1 The examples and preferred ranges of the arylene group and divalent heterocyclic group are the same as those in the above. Ar X2 and Ar X4 In the divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded, examples and preferred ranges of the arylene group and the divalent heterocyclic group are respectively Ar Y1 The examples and preferred ranges of the arylene group and divalent heterocyclic group are the same as those in the above. Ar X2 and Ar X4 In the above, examples of the divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded include Ar Y1 Examples of the divalent group include the same as the divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded to each other in the above formula.

[0192] Ar X1 ~Ar X4 and R X1 ~R X3 Examples of the substituents that the group represented by the formula (I) may have and their preferred ranges are: Y1 The examples and preferred ranges of the substituents that may be possessed by the group represented by the formula:

[0193] Examples of the constitutional unit represented by formula (X) include constitutional units represented by the following formula:

[0194] [ka]

[0195] [ka]

[0196] [ka]

[0197] [ka]

[0198] [ka]

[0199] [ka]

[0200] [ka]

[0201] Examples of the polymer compound (H) include polymer compounds HP-1 to HP-3.

[0202] [Table 1]

[0203] The polymer compound (H) may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, or other forms, but is preferably a copolymer obtained by copolymerizing a plurality of raw material monomers.

[0204] Since the driving voltage of the light-emitting device of this embodiment is lower, the number average molecular weight of the polymer compound (H) in terms of polystyrene is preferably 5×10 3 ~1×10 6 and more preferably 1×10 4 ~5×10 5 and more preferably 2 × 10 4 ~3×10 5 and particularly preferably 4 × 10 4 ~2×10 5 Since the driving voltage of the light-emitting device of this embodiment is lower, the weight average molecular weight of the polymer compound (H) in terms of polystyrene is preferably 1×10 4 ~2×10 6 and more preferably 2×10 4 ~1×10 6 and more preferably 5 × 10 4 ~5×10 5 and particularly preferably 1 × 10 5 ~3×10 5 is.

[0205] (Method for producing polymer compound (H)) The polymer compound (H) can be produced by a known polymerization method described in, for example, Chem. Rev., Vol. 109, pp. 897-1091 (2009), and examples of such methods include polymerization by coupling reactions using transition metal catalysts, such as Suzuki reaction, Yamamoto reaction, Buchwald reaction, Stille reaction, Negishi reaction, and Kumada reaction. In the above polymerization method, examples of the method for charging the monomers include a method in which the entire amount of the monomers is charged into the reaction system all at once, a method in which a part of the monomers is charged and reacted, and then the remaining monomers are charged all at once, continuously or in portions, and a method in which the monomers are charged continuously or in portions. Examples of the transition metal catalyst include a palladium catalyst and a nickel catalyst. Post-treatment of the polymerization reaction can be carried out using known methods, such as a method of removing water-soluble impurities by liquid separation, a method of adding the reaction solution after the polymerization reaction to a lower alcohol such as methanol, filtering the precipitate, and then drying it, either alone or in combination. When the purity of the first polymer compound is low, it can be purified by a conventional method such as recrystallization, reprecipitation, continuous extraction using a Soxhlet extractor, or column chromatography.

[0206] [Low molecular compound (h)] The molecular weight of the low molecular weight compound (h) is preferably 1×10 because this lowers the driving voltage of the light emitting device of this embodiment and makes it easy to synthesize the low molecular weight compound (h). 2 ~1×10 4 and more preferably 2×10 2 ~8×10 3 and more preferably 3×10 2 ~6×10 3 and particularly preferably 4 × 10 2 ~4×10 3 is.

[0207] The low molecular weight compound (h) may contain only one type of polycyclic aromatic hydrocarbon skeleton (h), or may contain two or more types. When the low molecular weight compound (h) contains an aromatic hydrocarbon skeleton (h), the number of types of aromatic hydrocarbon skeletons (h) is usually 1 to 30, and since this lowers the driving voltage of the light-emitting device of this embodiment and facilitates the synthesis of the low molecular weight compound (h), the number of types is preferably 1 to 10, more preferably 1 to 7, even more preferably 1 to 5, particularly preferably 1 to 3, and especially preferably 1 or 2. The low molecular weight compound (h) may contain only one aromatic hydrocarbon skeleton (h), or may contain two or more aromatic hydrocarbon skeletons (h). When the low molecular weight compound (h) contains an aromatic hydrocarbon skeleton (h), the number of aromatic hydrocarbon skeletons (h) is usually 1 to 50, and is preferably 1 to 30, more preferably 1 to 20, even more preferably 1 to 10, and particularly preferably 1 to 7, because this reduces the driving voltage of the light-emitting device of this embodiment and makes synthesis of the low molecular weight compound (h) easier.

[0208] The aromatic hydrocarbon skeleton (h) is preferably an aromatic hydrocarbon having 2 to 7 rings, more preferably an aromatic hydrocarbon having 2 to 6 rings, still more preferably naphthalene, anthracene, phenanthrene, dihydrophenanthrene, dibenzocycloheptane, fluorene, benzanthracene, benzophenanthrene, benzofluorene, dibenzanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene, benzofluoranthene, or spirobifluorene, particularly preferably naphthalene, anthracene, phenanthrene, fluorene, benzanthracene, benzophenanthrene, benzofluorene, dibenzanthracene, dibenzophenanthrene, dibenzofluorene, benzofluoranthene, or spirobifluorene, and particularly preferably naphthalene, anthracene, fluorene, benzophenanthrene, benzofluoranthene, or spirobifluorene.

[0209] The low molecular weight compound (h) having an aromatic hydrocarbon skeleton (h) can also be referred to as a low molecular weight compound (h) having an aromatic hydrocarbon group (h) containing an aromatic hydrocarbon skeleton (h). The aromatic hydrocarbon group (h) may be a group in which one or more hydrogen atoms directly bonded to atoms constituting the ring have been removed from the aromatic hydrocarbon skeleton (h), and the group may have a substituent. The substituent that the aromatic hydrocarbon group (h) may have is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, because this reduces the driving voltage of the light-emitting element of this embodiment; more preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group; even more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, and these groups may further have a substituent.

[0210] The aryl group in the substituent that the aromatic hydrocarbon group (h) may have is preferably a phenyl group or an aromatic hydrocarbon group (h), since this lowers the driving voltage of the light-emitting element of this embodiment, and these groups may further have a substituent.

[0211] The monovalent heterocyclic group in the substituent that the aromatic hydrocarbon group (h) may have is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring is removed from a monocyclic or bicyclic to hexacyclic heterocyclic compound, since this reduces the driving voltage of the light-emitting device of this embodiment, and more preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring is removed from a monocyclic, bicyclic or tricyclic heterocyclic compound.

[0039] The group is preferably a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) from pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine, or 5,10-dihydrophenazine, and particularly preferably a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) from pyridine, diazabenzene, triazine, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, or phenothiazine, and particularly preferably a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) from pyridine, diazabenzene, triazine, or carbazole, and these groups may further have a substituent.

[0212] In the substituted amino group in the substituent that the aromatic hydrocarbon group (h) may have, the substituent that the amino group has is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group, and these groups may further have a substituent. Examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituent that the amino group has are the same as the examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituent that the aromatic hydrocarbon group (h) may have, respectively.

[0213] The substituent that the aromatic hydrocarbon group (h) may further have is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, because this reduces the driving voltage of the light-emitting element of this embodiment and makes it easy to synthesize the low molecular weight compound (h), more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, and even more preferably an alkyl group, a cycloalkyl group, or an aryl group. These groups may further have a substituent, but preferably do not have a further substituent. Examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the aromatic hydrocarbon group (h) may further have are the same as the examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the aromatic hydrocarbon group (h) may have.

[0214] (Low molecular weight compound represented by formula (h-1)) The low molecular weight compound (h) is preferably a low molecular weight compound represented by formula (h-1), since the driving voltage of the light emitting device of this embodiment is lowered.

[0215] n 1h is usually an integer of 0 to 10, and is preferably an integer of 1 to 7, more preferably an integer of 1 to 5, and even more preferably an integer of 1 to 3, since this lowers the driving voltage of the light-emitting device of this embodiment.

[0216] Ar 1h In the above, examples and preferred ranges of the polycyclic aromatic hydrocarbon are the same as the examples and preferred ranges of the polycyclic aromatic hydrocarbon in the aromatic hydrocarbon skeleton (h). Ar 1h The substituent that may be contained in the group (I) is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, or an aryloxy group, because it reduces the driving voltage of the light-emitting element of this embodiment, more preferably an alkyl group, a cycloalkyl group, an alkoxy group, or a cycloalkoxy group, even more preferably an alkyl group or a cycloalkyl group, and particularly preferably an alkyl group, and these groups may further contain a substituent.

[0217] Ar 1h Examples and preferred examples of the substituents which may be further substituted by the substituents which may be substituted by the The range is the same as the examples and preferred range of the substituents that may be further substituted by the substituent that the aromatic hydrocarbon group (h) may have.

[0218] R 1hExamples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the aromatic hydrocarbon group (h) may have are the same as the examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the aromatic hydrocarbon group (h) may have. R 1h Examples and preferred ranges of the substituents which may be further substituted by the substituents which may be substituted by the aromatic hydrocarbon group (h) are the same as the examples and preferred ranges of the substituents which may be further substituted by the substituents which may be substituted by the aromatic hydrocarbon group (h).

[0219] Examples of the low molecular weight compound (h) include compounds represented by the following formula: 1 represents an oxygen atom or a sulfur atom. 2 represents a group represented by -CH= or -N=. Z 2 When there are multiple Z's, they may be the same or different. 3 represents a hydrogen atom or an alkyl group. 3 When there are multiple groups, they may be the same or different.

[0220] [ka]

[0221] [ka]

[0222] [ka]

[0223] [ka]

[0224] [ka]

[0225] [ka]

[0226] <Composition> The composition of the present embodiment is a composition containing at least two compounds selected from the group consisting of low molecular weight compound (b), high molecular weight compound (H) and low molecular weight compound (h), and a solvent, wherein at least one of the at least two compounds contained in the composition is low molecular weight compound (b) (hereinafter also referred to as "composition 1"). Alternatively, the composition of this embodiment is a composition (hereinafter also referred to as "composition 2") that contains a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') and a solvent.

[0227] The composition of the present embodiment can be suitably used, for example, as a composition for a light-emitting device. Furthermore, a light-emitting device formed using the composition of the present embodiment (hereinafter also referred to as "light-emitting device of the present embodiment") has a lower driving voltage.

[0228] [Composition 1] Composition 1 may be, for example, a composition containing one or more types of low molecular weight compounds (b), at least one compound selected from the group consisting of polymer compound (H) and low molecular weight compound (h), and a solvent (hereinafter also referred to as "composition 1-1"), or a composition containing two or more types of low molecular weight compounds (b) and a solvent but not containing polymer compound (H) or low molecular weight compound (h) (hereinafter also referred to as "composition 1-2"). Composition 1 is preferably composition 1-1, since composition 1 lowers the driving voltage of the light-emitting device of this embodiment.

[0229] (Composition 1-1) Composition 1-1 is a composition containing a low molecular weight compound (b), at least one compound selected from the group consisting of a high molecular weight compound (H) and a low molecular weight compound (h), and a solvent. Composition 1-1 may contain only one kind or two or more kinds of each of the low molecular weight compound (b), the high molecular weight compound (H), the low molecular weight compound (h) and the solvent. The types of low molecular weight compound (b), high molecular weight compound (H), low molecular weight compound (h) and solvent contained in composition 1-1 are each usually 1 to 20 types, preferably 1 to 10 types, more preferably 1 to 5 types, even more preferably 1 to 3 types, particularly preferably 1 or 2 types, and especially preferably 1 type.

[0230] The total content of the low molecular weight compound (b), the polymer compound (H), the low molecular weight compound (h), and the solvent in composition 1-1 may be within a range that allows the composition of this embodiment to function. The total content of the low molecular weight compound (b), the polymer compound (H), the low molecular weight compound (h), and the solvent in the composition of this embodiment may be, for example, 0.1 to 100 mass% or 1 to 100 mass% based on the total amount of the composition of this embodiment. Since this further reduces the driving voltage of the light-emitting device of this embodiment, the total content is preferably 10 to 100 mass%, more preferably 30 to 100 mass%, even more preferably 50 to 100 mass%, particularly preferably 70 to 100 mass%, and especially preferably 90 to 100 mass%.

[0231] In composition 1-1, the low molecular weight compound (b) and the low molecular weight compound (h) are preferably different, and the low molecular weight compound (h) is more preferably a low molecular weight compound that does not contain a heterocyclic skeleton (b).

[0232] In composition 1-1, the content of low molecular weight compound (b) may be within a range that allows the composition of this embodiment to function. In composition 1-1, the content of low molecular weight compound (b) may be, for example, 0.01 to 99.9 parts by mass, and more preferably 0.02 to 100 parts by mass, when the total content of low molecular weight compound (b), high molecular weight compound (H), and low molecular weight compound (h) is taken as 100 parts by mass. The amount may be 0.05 to 99 parts by mass, or 0.03 to 90 parts by mass, and is preferably 0.05 to 70 parts by mass, more preferably 0.1 to 50 parts by mass, even more preferably 0.2 to 30 parts by mass, particularly preferably 0.4 to 10 parts by mass, and especially preferably 0.5 to 5 parts by mass, since this further reduces the driving voltage of the light-emitting element of this embodiment.

[0233] In composition 1-1, the low molecular weight compound (b) preferably interacts with the high molecular weight compound (H) and / or the low molecular weight compound (h) physically, chemically, or electrically. This interaction makes it possible to improve or adjust the light-emitting properties, charge transport properties, or charge injection properties of the composition of this embodiment, thereby lowering the driving voltage of the light-emitting device of this embodiment. In the composition 1-1, taking the light-emitting material as an example, the low molecular weight compound (b) electrically interacts with the high molecular weight compound (H) and / or the low molecular weight compound (h), and electrical energy is efficiently transferred from the high molecular weight compound (H) and / or the low molecular weight compound (h) to the low molecular weight compound (b), thereby enabling the low molecular weight compound (b) to emit light more efficiently, and the driving voltage of the light-emitting element of this embodiment becomes lower.

[0234] From the above viewpoint, in composition 1-1, the driving voltage of the light-emitting device of this embodiment becomes lower, so it is preferable that the polymer compound (H) and the low molecular weight compound (h) have at least one function selected from hole injection property, hole transport property, electron injection property, and electron transport property, and it is more preferable that they are host materials. From the above viewpoint, in composition 1-1, the driving voltage of the light-emitting device of this embodiment becomes lower, so that the low molecular weight compound (b) preferably has luminescence properties, and more preferably is a luminescent material. From the above viewpoint, in composition 1-1, the lowest excited singlet state (S1) possessed by the polymer compound (H) and the low molecular weight compound (h) preferably has an energy level higher than that of the lowest excited singlet state (S1) possessed by the low molecular weight compound (b), since this lowers the driving voltage of the light-emitting device of this embodiment. From the above viewpoint, in composition 1-1, the lowest excited triplet state (T1) possessed by the polymer compound (H) and the low molecular weight compound (h) preferably has an energy level higher than that of the lowest excited triplet state (T1) possessed by the low molecular weight compound (b), since this results in a lower driving voltage for the light-emitting device of this embodiment.

[0235] Since the light-emitting device of this embodiment can be produced by a wet process, it is preferable that the polymer compound (H) and the low molecular weight compound (h) are soluble in a solvent capable of dissolving the low molecular weight compound (b). Composition 1-1 may be a composition (hereinafter also referred to as "composition 1-1'") containing a low molecular weight compound (b), at least one compound selected from the group consisting of a polymer compound (H) and a low molecular weight compound (h), a solvent, and at least one material selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light-emitting material, and an antioxidant.

[0236] In composition 1-1′, the hole transport material, hole injection material, electron transport material, electron injection material, and light emitting material are preferably different from the low molecular weight compound (b), the polymer compound (H), and the low molecular weight compound (h); it is more preferable that the hole transport material, hole injection material, electron transport material, electron injection material, and light emitting material are low molecular weight compounds and different from the low molecular weight compounds (b) and (h); and it is even more preferable that the hole transport material, hole injection material, electron transport material, electron injection material, and light emitting material are low molecular weight compounds that do not have a heterocyclic skeleton (b) or a polycyclic aromatic hydrocarbon skeleton (hereinafter, also referred to as low molecular weight compound (Nh)).

[0237] In composition 1-1', the total content of low molecular weight compound (b), polymer compound (H), low molecular weight compound (h), solvent, hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant may be within a range that allows composition 1-1' to function. In composition 1-1', the total content of low molecular weight compound (b), polymer compound (H), low molecular weight compound (h), solvent, hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant may be, for example, 0.1 to 100 mass% or may be 1 to 100 mass% based on the total amount of composition 1-1'. Since this reduces the driving voltage of the light emitting device of this embodiment, the total content is preferably 10 to 100 mass%, more preferably 30 to 100 mass%, even more preferably 50 to 100 mass%, particularly preferably 70 to 100 mass%, and particularly preferably 90 to 100 mass%.

[0238] (solvent) Composition 1-1 and Composition 1-1′ are suitable for producing light-emitting devices using a wet method such as spin coating, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, spray coating, screen printing, flexographic printing, offset printing, inkjet printing, capillary coating, and nozzle coating.

[0239] The viscosity of Composition 1-1 and Composition 1-1' may be adjusted depending on the type of printing method. When applied to a printing method in which the solution passes through a discharge device, such as inkjet printing, the viscosity is preferably 1 mPa·s to 20 mPa·s at 25°C to prevent clogging and deflection during discharge.

[0240] The solvent contained in Composition 1-1 and Composition 1-1' is preferably a solvent capable of dissolving or uniformly dispersing the solid content in Composition 1-1 and Composition 1-1'. Examples of the solvent include chlorine-based solvents such as 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, and o-dichlorobenzene; ether-based solvents such as tetrahydrofuran, dioxane, anisole, and 4-methylanisole; aromatic hydrocarbon-based solvents such as toluene, xylene, mesitylene, ethylbenzene, n-hexylbenzene, and cyclohexylbenzene; cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-dodecane, and bicyclohexyl. aliphatic hydrocarbon solvents such as acetone, methyl ethyl ketone, cyclohexanone, acetophenone, and the like; ester solvents such as ethyl acetate, butyl acetate, ethyl cellosolve acetate, methyl benzoate, phenyl acetate, and the like; polyhydric alcohol solvents such as ethylene glycol, glycerin, 1,2-hexanediol, and the like; alcohol solvents such as isopropyl alcohol and cyclohexanol, and the like; sulfoxide solvents such as dimethyl sulfoxide, and the like; and amide solvents such as N-methyl-2-pyrrolidone and N,N-dimethylformamide, and the like. The solvents may be used alone or in combination of two or more.

[0241] The content of the solvent in Composition 1-1 and Composition 1-1' may be within a range that allows the functions of Composition 1-1 and Composition 1-1' to be exhibited. The content of the solvent in Composition 1-1 and Composition 1-1' may be, for example, 1 to 99.9999 parts by mass, 10 to 99.999 parts by mass, 30 to 99.998 parts by mass, or 50 to 99.995 parts by mass, relative to 100 parts by mass of the total content of the low molecular weight compound (b), the high molecular weight compound (H), the low molecular weight compound (h), the solvent, the hole transport material, the hole injection material, the electron transport material, the electron injection material, the light-emitting material, and the antioxidant. Since this lowers the driving voltage of the light-emitting device of this embodiment, the content is preferably 70 to 99.99 parts by mass, more preferably 80 to 99.95 parts by mass, even more preferably 85 to 99.9 parts by mass, particularly preferably 90 to 99.5 parts by mass, and especially preferably 95 to 99 parts by mass.

[0242] (hole transport material) Hole transport materials are classified into low molecular weight compounds and high molecular weight compounds. The hole transport material may have a group. One type of hole transport material may be used alone, or two or more types may be used in combination. In the composition 1-1', the hole transport material is preferably a low molecular weight compound (Nh). Examples of low molecular weight compounds include aromatic amine compounds such as triphenylamine and its derivatives, N,N'-di-1-naphthyl-N,N'-diphenylbenzidine (α-NPD), and N,N'-diphenyl-N,N'-di(m-tolyl)benzidine (TPD).

[0243] Examples of the polymer compound include polyvinylcarbazole and its derivatives, and polyarylene and its derivatives having an aromatic amine structure in the side chain or main chain. The polymer compound may also be a compound to which an electron-accepting moiety is bonded, such as fullerene, tetrafluorotetracyanoquinodimethane, tetracyanoethylene, and trinitrofluorenone. When composition 1-1' contains a hole transport material, the content of the hole transport material may be within a range that allows composition 1-1' to function. When composition 1-1' contains a hole transport material, the content of the hole transport material is typically 1 to 10,000 parts by mass, relative to 100 parts by mass of the total content of low molecular weight compound (b), high molecular weight compound (H), and low molecular weight compound (h).

[0244] (electron transport material) Electron transport materials are classified into low molecular weight compounds and high molecular weight compounds. The electron transport material may have a crosslinking group. The electron transport material may be used alone or in combination of two or more types. In composition 1-1′, the electron transport material is preferably a low molecular weight compound (Nh). Examples of low molecular weight compounds include metal complexes having 8-hydroxyquinoline as a ligand, oxadiazole, anthraquinodimethane, benzoquinone, naphthoquinone, anthraquinone, tetracyanoanthraquinodimethane, fluorenone, diphenyldicyanoethylene, and diphenoquinone, as well as derivatives thereof.

[0245] Examples of the polymer compound include polyphenylene, polyfluorene, and derivatives thereof. The polymer compound may be doped with a metal. When composition 1-1' contains an electron transport material, the content of the electron transport material may be within a range that allows composition 1-1' to function. When composition 1-1' contains an electron transport material, the content of the electron transport material is typically 1 to 10,000 parts by mass, relative to 100 parts by mass of the total content of low molecular weight compound (b), high molecular weight compound (H), and low molecular weight compound (h).

[0246] (Hole injection material and electron injection material) The hole injection material and the electron injection material are each classified into a low molecular weight compound and a high molecular weight compound. The hole injection material and the electron injection material may have a crosslinking group. The hole injection material and the electron injection material may each be used alone or in combination of two or more types. In composition 1-1′, the hole injection material and the electron injection material are preferably low molecular weight compounds (Nh). Examples of low molecular weight compounds include metal phthalocyanines such as copper phthalocyanine; carbon; metal oxides such as molybdenum and tungsten; and metal fluorides such as lithium fluoride, sodium fluoride, cesium fluoride, and potassium fluoride.

[0247] Examples of the polymer compounds include polyaniline, polythiophene, polypyrrole, polyphenylene vinylene, polythienylene vinylene, polyquinoline, and polyquinoxaline. and derivatives thereof; and conductive polymers such as polymers containing an aromatic amine structure in the main chain or side chain.

[0248] When composition 1-1' contains a hole injection material and / or an electron injection material, the contents of the hole injection material and the electron injection material may be within a range that allows composition 1-1' to function. When composition 1-1' contains a hole injection material and / or an electron injection material, the contents of the hole injection material and the electron injection material are typically 1 to 10,000 parts by mass, relative to 100 parts by mass of the total content of low molecular weight compound (b), high molecular weight compound (H), and low molecular weight compound (h).

[0249] Ion doping The hole injection material and the electron injection material may be doped with ions. For example, when the hole injection material and the electron injection material include a conductive polymer, the electrical conductivity of the conductive polymer is preferably 1×10 -5 S / cm~1×10 3 In order to set the electrical conductivity of the conductive polymer in this range, the conductive polymer can be doped with an appropriate amount of ions. The types of ions doped into the hole injection material and the electron injection material include, for example, anions for the hole injection material and cations for the electron injection material. Examples of anions include polystyrene sulfonate ions, alkylbenzene sulfonate ions, and camphor sulfonate ions. Examples of cations include lithium ions, sodium ions, potassium ions, and tetrabutylammonium ions. The doping ions may be used singly or in combination of two or more kinds.

[0250] (luminescent material) Light-emitting materials are classified into low-molecular-weight compounds and high-molecular-weight compounds. The light-emitting material may have a crosslinking group. The light-emitting material may be used alone or in combination of two or more types. In composition 1-1', the light-emitting material is preferably a low molecular weight compound (Nh). Examples of low molecular weight compounds include naphthalene and its derivatives, anthracene and its derivatives, perylene and its derivatives, and phosphorescent compounds having iridium, platinum, or europium as a central metal. Examples of the polymer compound include polymer compounds containing a constitutional unit represented by formula (Y) and / or a constitutional unit represented by formula (X).

[0251] Examples of the phosphorescent compound include the metal complexes shown below.

[0252] [ka]

[0253] [ka]

[0254] [ka]

[0255] [ka]

[0256] [ka]

[0257] When composition 1-1' contains a luminescent material, the content of the luminescent material may be within a range that allows composition 1-1' to function. When composition 1-1' contains a luminescent material, the content of the luminescent material is typically 1 to 10,000 parts by mass, where the total content of low molecular weight compound (b), polymer compound (H), and low molecular weight compound (h) is 100 parts by mass.

[0258] (antioxidant) The antioxidant may be any compound that is soluble in the same solvent as the low molecular weight compound (b), the high molecular weight compound (H), and the low molecular weight compound (h) and does not inhibit light emission or charge transport, and examples thereof include phenol-based antioxidants and phosphorus-based antioxidants. The antioxidants may be used alone or in combination of two or more.

[0259] When composition 1-1' contains an antioxidant, the content of the antioxidant may be within a range that allows composition 1-1' to function. When composition 1-1' contains an antioxidant, the content of the antioxidant is typically 0.00001 to 10 parts by mass, relative to 100 parts by mass of the total content of low molecular weight compound (b), high molecular weight compound (H), low molecular weight compound (h), and solvent.

[0260] (Composition 1-2) Composition 1-2 is a composition that contains two or more types of low molecular weight compounds (b) and a solvent, but does not contain a high molecular weight compound (H) or a low molecular weight compound (h). Composition 1-2 may contain only two kinds of low molecular weight compounds (b), or may contain three or more kinds of low molecular weight compounds (b). Composition 1-2 may contain only one kind of solvent, or may contain two or more kinds of solvents. The number of types of low molecular weight compound (b) contained in composition 1-2 is usually 2 to 20, preferably 2 to 10, more preferably 2 to 5, even more preferably 2 or 3, and particularly preferably 2. Examples and preferred ranges of the types of solvents contained in composition 1-2 are the same as the examples and preferred ranges of the types of solvents contained in composition 1-1.

[0261] The total content of the two or more low-molecular-weight compounds (b) and the solvent in composition 1-2 may be within a range that allows composition 1-2 to function. The total content of the two or more low-molecular-weight compounds (b) and the solvent in composition 1-2 may be, for example, 0.1 to 100 mass%, 1 to 100 mass%, 10 to 100 mass%, 30 to 100 mass%, 50 to 100 mass%, 70 to 100 mass%, or 90 to 100 mass%, based on the total amount of the composition of this embodiment.

[0262] Composition 1-2 may be a composition (hereinafter also referred to as "composition 1-2'") that contains two or more low molecular weight compounds (b), a solvent, and at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, and an antioxidant, but does not contain a polymer compound (H) or a low molecular weight compound (h). Examples and preferred ranges of the hole transport material, hole injection material, electron transport material, electron injection material, and light emitting material in composition 1-2' are the same as those of the hole transport material, hole injection material, electron transport material, electron injection material, and light emitting material in composition 1-1', respectively.

[0263] The content of the solvent in Composition 1-2 and Composition 1-2' may be within a range that allows the composition 1-2 and composition 1-2' to function. The content of the solvent in Composition 1-2 and composition 1-2' may be, for example, 1 to 99.9999 parts by mass, 10 to 99.999 parts by mass, 30 to 99.998 parts by mass, 50 to 99.995 parts by mass, 70 to 99.99 parts by mass, 80 to 99.95 parts by mass, 85 to 99.9 parts by mass, 90 to 99.5 parts by mass, or 95 to 99 parts by mass, relative to 100 parts by mass of the total content of the two or more low molecular weight compounds (b), solvent, hole transport material, hole injection material, electron transport material, electron injection material, light-emitting material, and antioxidant.

[0264] In composition 1-2', the total content of two or more low molecular weight compounds (b), solvent, hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant may be within a range that allows composition 1-2' to function. In composition 1-2', the total content of two or more low molecular weight compounds (b), solvent, hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant may be, for example, 0.1 to 100 mass%, 1 to 100 mass%, 10 to 100 mass%, 30 to 100 mass%, 50 to 100 mass%, 70 to 100 mass%, or 90 to 100 mass%, based on the total amount of composition 1-2'.

[0265] In the case where composition 1-2′ contains at least one material selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, and a light emitting material, the content of each of the hole transport material, the hole injection material, the electron transport material, the electron injection material, and the light emitting material is the same as that of composition 1-2′. When composition 1-2′ contains at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, and a light emitting material, the content of each of the hole transport material, the hole injection material, the electron transport material, the electron injection material, and the light emitting material is usually 1 to 10,000 parts by mass, based on 100 parts by mass of the content of the two or more low molecular weight compounds (b).

[0266] When composition 1-2' contains an antioxidant, the content of the antioxidant may be within a range that allows composition 1-2' to function. When composition 1-2' contains an antioxidant, the content of the antioxidant is typically 0.00001 to 10 parts by mass, relative to 100 parts by mass of the total content of the two or more low-molecular-weight compounds (b) and the solvent.

[0267] (Composition 2) Composition 2 is a composition containing a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1′) (hereinafter also referred to as “low molecular weight compound (b1-1′)”) and a solvent. The composition 2 may contain only one kind of low molecular weight compound (b1-1') and one kind of solvent, or may contain two or more kinds of low molecular weight compound (b1-1') and one kind of solvent. The examples and preferred ranges of the types of low molecular weight compound (b1-1') and solvent contained in composition 2 are the same as the examples and preferred ranges of the types of low molecular weight compound (b) and solvent described in the section on composition 1.

[0268] The total content of the low molecular weight compound (b1-1') and the solvent in composition 2 may be within a range that allows the composition 2 to function. The total content of the low molecular weight compound (b1-1') and the solvent in composition 2 may be, for example, 0.1 to 100 mass%, 1 to 100 mass%, 10 to 100 mass%, 30 to 100 mass%, 50 to 100 mass%, 70 to 100 mass%, or 90 to 100 mass%, based on the total amount of composition 2.

[0269] Composition 2 may be a composition (hereinafter also referred to as "Composition 2'") containing a low molecular weight compound (b1-1'), a solvent, and at least one selected from the group consisting of a polymer compound (H), a low molecular weight compound (h), a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light-emitting material, and an antioxidant. Examples and preferred ranges of the low molecular weight compound (b1-1'), solvent, polymer compound (H), low molecular weight compound (h), hole transport material, hole injection material, electron transport material, electron injection material, light-emitting material, and antioxidant in Composition 2' are the same as those of the low molecular weight compound (b), solvent, polymer compound (H), low molecular weight compound (h), hole transport material, hole injection material, electron transport material, electron injection material, light-emitting material, and antioxidant described in the section for Composition 1.

[0270] In composition 2', the total content of low molecular weight compound (b1-1'), solvent, polymer compound (H), low molecular weight compound (h), hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant may be within a range that allows the composition to function as composition 2'. In composition 2', the total content of low molecular weight compound (b), solvent, polymer compound (H), low molecular weight compound (h), hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant may be, for example, 0.1 to 100 mass% or may be 1 to 100 mass% based on the total amount of the composition of this embodiment. Since this further reduces the driving voltage of the light emitting device of this embodiment, it is preferably 10 to 100 mass%, more preferably 30 to 100 mass%, even more preferably 50 to 100 mass%, particularly preferably 70 to 100 mass%, and particularly preferably 90 to 100 mass%.

[0271] In the composition 2', a low molecular weight compound (b1-1'), a solvent, a polymer compound (H), a low molecular weight compound (h), a hole transport material, a hole injection material, an electron transport material, an electron injection material, and a light emitting material The examples and preferred ranges of the contents of the low molecular weight compound (b), solvent, polymer compound (H), low molecular weight compound (h), hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant described in the section on Composition 1 can be applied to these contents.

[0272] <Membrane> The film of this embodiment is a film formed using the composition of this embodiment. The film of this embodiment is suitable as a light-emitting layer in a light-emitting device. The film of this embodiment can be produced, for example, by using the composition of this embodiment by the wet method described in the section on Composition 1 (Solvent). The thickness of the film in this embodiment is usually 1 nm to 10 μm.

[0273] <Light-emitting element> The light emitting device of this embodiment is a light emitting device formed using the composition of this embodiment described above. The light-emitting element of this embodiment may include, for example, an anode, a cathode, and an organic layer formed using the above-described composition and disposed between the anode and the cathode.

[0274] The light-emitting device of this embodiment may be a light-emitting device formed using the composition of this embodiment, or may be a light-emitting device formed using the composition of this embodiment by a wet method as described in the section (Solvent) of Composition 1. The light-emitting device of this embodiment may be, for example, a light-emitting device including an anode, a cathode, and an organic layer provided between the anode and the cathode, in which the organic layer is formed using the composition of this embodiment, or may be an organic layer formed using the composition of this embodiment by a wet method as described in the section (Solvent) of Composition 1.

[0275] As described above, the light-emitting element of this embodiment has organic layers formed using the composition of this embodiment (hereinafter, these layers are also collectively referred to as "layers of this embodiment").

[0276] [Layer composition] The layer of this embodiment is usually one or more layers selected from the group consisting of a light-emitting layer, a hole-transporting layer, a hole-injecting layer, an electron-transporting layer, and an electron-injecting layer, and is preferably a light-emitting layer. These layers can be formed using the same method as for producing the above-mentioned film. Layers other than the layer of this embodiment, such as the light-emitting layer, hole-transport layer, hole-injection layer, electron-transport layer, and electron-injection layer, each contain a light-emitting material, a hole-transport material, a hole-injection material, an electron-transport material, and an electron-injection material. These layers can be formed by using, for example, a vapor deposition method or a wet method.

[0277] The light-emitting element has a light-emitting layer between an anode and a cathode. From the viewpoint of hole injection and hole transport properties, the light-emitting element of this embodiment preferably has at least one hole injection layer and hole transport layer between the anode and the light-emitting layer, and from the viewpoint of electron injection and electron transport properties, preferably has at least one electron injection layer and electron transport layer between the cathode and the light-emitting layer. Examples of materials for the hole transport layer, electron transport layer, light-emitting layer, hole injection layer, and electron injection layer include the composition of this embodiment as well as the hole transport material, electron transport material, light-emitting material, hole injection material, and electron injection material described above, respectively.

[0278] When the materials for the hole transport layer, electron transport layer, and light-emitting layer are soluble in a solvent used to form the hole transport layer, electron transport layer, and layer adjacent to the light-emitting layer in the fabrication of a light-emitting device, the materials preferably have a crosslinking group to prevent the materials from dissolving in the solvent. After forming each layer using a material having a crosslinking group, the layer can be made insoluble by crosslinking the crosslinking group.

[0279] [Substrate / Electrode] The substrate in the light-emitting element may be any substrate on which electrodes can be formed and which is not chemically changed when an organic layer is formed, such as a substrate made of a material such as glass, plastic, silicon, etc. In the case of an opaque substrate, it is preferable that the electrode farthest from the substrate is transparent or translucent. Examples of materials for the anode include conductive metal oxides and translucent metals, and preferred are indium oxide, zinc oxide, and tin oxide; conductive compounds such as indium tin oxide (ITO) and indium zinc oxide; silver-palladium-copper composite (APC); NESA, gold, platinum, silver, and copper.

[0280] Cathode materials include, for example, metals such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, zinc, and indium; alloys of two or more of these; alloys of one or more of these with one or more of silver, copper, manganese, titanium, cobalt, nickel, tungsten, and tin; and graphite and graphite intercalation compounds. Examples of alloys include magnesium-silver alloy, magnesium-indium alloy, magnesium-aluminum alloy, indium-silver alloy, lithium-aluminum alloy, lithium-magnesium alloy, lithium-indium alloy, and calcium-aluminum alloy. The anode and cathode may each have a laminated structure of two or more layers.

[0281] [Application] The light-emitting element of this embodiment can be suitably used as a light source for backlighting of a liquid crystal display device, a light source for illumination, an organic EL light source, and a display device for a computer, a television, a mobile terminal, etc. (for example, an organic EL display and an organic EL television). [Example]

[0282] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0283] In the examples, the polystyrene-equivalent number average molecular weight (Mn) and polystyrene-equivalent weight average molecular weight (Mw) of the polymer compound were determined by size exclusion chromatography (SEC) using tetrahydrofuran as the mobile phase. The SEC measurement conditions were as follows: The polymer compound to be measured was dissolved in tetrahydrofuran at a concentration of approximately 0.05% by mass, and 10 μL of the solution was injected into the SEC. The mobile phase was run at a flow rate of 2.0 mL / min. The column used was a PLgel MIXED-B (manufactured by Polymer Laboratories). The detector used was a UV-VIS detector (manufactured by Shimadzu Corporation, product name: SPD-10Avp).

[0284] ΔE of the compound ST The calculation of the ΔE value of the compound was carried out by optimizing the ground state of the compound using the density functional theory at the B3LYP level. At that time, 6-31G* was used as the basis function. Then, using the obtained optimized structure, the ΔE value of the compound was calculated using the time-dependent density functional theory at the B3LYP level. ST The calculation was performed using Gaussian09 as a quantum chemistry calculation program.

[0285] The maximum peak wavelength of the emission spectrum of the compound at room temperature was measured at room temperature using a spectrophotometer (JASCO Corporation, FP-6500). -4 The xylene solution dissolved at a concentration of 100% by mass was used as the sample. Ultraviolet (UV) light with a wavelength of 325 nm was used as the excitation light.

[0286] <Compounds M1 to M11, BC-G1, B-G1 to B-G6, BC-B1 to BC-B3, B-B1 to B-B3, HCM1, and HM1 to HM9> Compound M1 was synthesized according to the method described in JP 2011-174062 A. Compound M2 was synthesized according to the method described in International Publication No. 2005 / 049546. Compound M3 was a commercially available product. Compound M4 was synthesized according to the method described in JP-A-2008-106241. Compound M5 was synthesized according to the method described in JP-A-2010-189630. Compound M6 was synthesized according to the method described in WO 2013 / 191088. Compound M7 was synthesized according to the method described in WO 2015 / 008851. Compound M8 was a commercially available product. Compound M9 was synthesized according to the method described in WO 2016 / 031639. Compound M10 was synthesized according to the method described in WO 2012 / 086671. Compound M11 was synthesized according to the method described in JP-A-2010-189630. Compound BC-G1 was synthesized according to the method described in WO 2020 / 080528. Compound B-G1 was synthesized according to the method described in Angew. Chem. Int. Ed. 2020, 59, 17442-17446. Compound B-G2 was synthesized according to the method described in Angew. Chem. Int. Ed. 2020, 59, 17499-17503. Compounds B-G3 to B-G6 were synthesized according to the method described in WO 2022 / 034916. Compound BC-B1 was synthesized according to the method described in WO 2015 / 102118. Compound BC-B2 was synthesized according to the method described in Chem. Eur. J. 2022, 28, e202201605. Compound BC-B3 was manufactured by Luminescence Technology. Compound B-B1 was synthesized according to the method described in JP 2022-024744 A. Compound B-B2 was manufactured by Luminescence Technology. Compound B-B3 was synthesized according to the method described in WO 2018 / 212169. The compound HCM1 used was manufactured by Sigma-Aldrich. Compound HM1 manufactured by Tokyo Chemical Industry Co., Ltd. was used. Compound HM2 manufactured by Luminescence Technology was used. Compound HM3 was synthesized according to the method described in WO 2008 / 059713. Compound HM4 was synthesized according to the method described in Organic Electronics, 2014, 15, 2802-2809. Compound HM5 was synthesized according to the method described in WO 2017 / 038613. Compound HM6 was synthesized according to the method described in WO 2017 / 038613. The compound HM7 used was manufactured by 1-Material. The compound HM8 used was manufactured by Luminescence Technology. Compound HM9 was synthesized according to the method described in JP-A-2023-158646.

[0287] [ka]

[0288] [ka]

[0289] [ka]

[0290] [ka]

[0291] [ka]

[0292] [ka]

[0293] [ka]

[0294] [ka]

[0295] [ka]

[0296] [ka]

[0297] [ka]

[0298] [ka]

[0299] ΔE of compound BC-G1 ST The maximum peak wavelength of the emission spectrum of the compound BC-G1 at room temperature was 507 nm. The half-width of the maximum peak of the emission spectrum of the compound BC-G1 at room temperature was 27 nm. ΔE of compound B-G1 ST The maximum peak wavelength of the emission spectrum of Compound B-G1 at room temperature was 515 nm. The half-width of the maximum peak of the emission spectrum of Compound B-G1 at room temperature was 38 nm. ΔE of compound B-G2 ST The maximum peak wavelength of the emission spectrum of Compound B-G2 at room temperature was 522 nm. The half-width of the maximum peak of the emission spectrum of Compound B-G2 at room temperature was 27 nm. ΔE of compound B-G3 ST The maximum peak wavelength of the emission spectrum of Compound B-G3 at room temperature was 527 nm. The half-width of the maximum peak of the emission spectrum of Compound B-G3 at room temperature was 18 nm. ΔE of compound B-G4 ST The maximum peak wavelength of the emission spectrum of Compound B-G4 at room temperature was 527 nm. The half-width of the maximum peak of the emission spectrum was 18 nm. ΔE of compound B-G5 STThe maximum peak wavelength of the emission spectrum of Compound B-G5 at room temperature was 519 nm. The half-width of the maximum peak of the emission spectrum of Compound B-G5 at room temperature was 18 nm. ΔE of compound B-G6 ST The maximum peak wavelength of the emission spectrum of Compound B-G6 at room temperature was 518 nm. The half-width of the maximum peak of the emission spectrum of Compound B-G6 at room temperature was 19 nm. ΔE of compound BC-B1 ST The maximum peak wavelength of the emission spectrum of the compound BC-B1 at room temperature was 453 nm. The half-width of the maximum peak of the emission spectrum of the compound BC-B1 at room temperature was 21 nm. ΔE of compound BC-B2 ST The maximum peak wavelength of the emission spectrum of the compound BC-B2 at room temperature was 457 nm. The half-width of the maximum peak of the emission spectrum of the compound BC-B2 at room temperature was 24 nm. ΔE of compound BC-B3 ST The maximum peak wavelength of the emission spectrum of the compound BC-B3 at room temperature was 454 nm. The half-width of the maximum peak of the emission spectrum of the compound BC-B3 at room temperature was 24 nm. ΔE of compound B-B1 ST The maximum peak wavelength of the emission spectrum of Compound B-B1 at room temperature was 464 nm. The half-width of the maximum peak of the emission spectrum of Compound B-B1 at room temperature was 22 nm. ΔE of compound B-B2 ST The maximum peak wavelength of the emission spectrum of Compound B-B2 at room temperature was 467 nm. The half-width of the maximum peak of the emission spectrum of Compound B-B2 at room temperature was 15 nm. ΔE of Compound B-B3 STThe maximum peak wavelength of the emission spectrum of Compound B-B3 at room temperature was 463 nm. The half-width of the maximum peak of the emission spectrum of Compound B-B3 at room temperature was 14 nm.

[0300] <Synthesis Example> Synthesis of polymer compounds HTL and HP1 to HP4 The polymer compounds HTL and HP1 to HP4 were synthesized using the compounds of the types and molar ratios shown in Table 2 by the synthesis methods shown in the same table. The Mn and Mw of the obtained polymer compounds were as shown in Table 2. The synthesis of the polymer compound HTL will be explained as an example below. The polymer compound HTL was synthesized using compounds M1, M2, M3, and M4 according to the method described in JP 2012-144722 A. The Mn of the polymer compound HTL was 8.0 × 10 4 and Mw is 2.6 × 10 5 It was. The polymer compound HTL is a copolymer having a molar ratio of 50:30:12.5:7.5 of structural units derived from compound M1, structural units derived from compound M2, structural units derived from compound M3, and structural units derived from compound M4, based on the theoretical value calculated from the amounts of the raw materials charged.

[0301] [Table 2]

[0302] Example D1 Fabrication and Evaluation of Light-Emitting Device D1 (Formation of anode and hole injection layer) An anode was formed by sputtering a 45-nm thick ITO film on a glass substrate. A 35-nm thick film of hole injection material ND-3202 (manufactured by Nissan Chemical Co., Ltd.) was spin-coated onto the anode. The substrate with the hole injection layer laminated thereon was heated on a hot plate at 50°C for 3 minutes in an air atmosphere, and then further heated at 230°C for 15 minutes to form a hole injection layer. (Formation of hole transport layer) The polymer compound HTL was dissolved in xylene at a concentration of 0.7% by mass. The resulting xylene solution was used to form a film with a thickness of 20 nm on the hole injection layer by spin coating, and the film was heated on a hot plate at 200°C for 30 minutes in a nitrogen gas atmosphere to form a hole transport layer. This heating caused the polymer compound HTL to become crosslinked. (Formation of the Light-Emitting Layer) Compound HM3 and Compound B-G1 (Compound HM3 / Compound B-G1=98% by mass / 2% by mass) were dissolved in toluene at a concentration of 2% by mass. The resulting toluene solution was spin-coated on the hole transport layer to form a film with a thickness of 60 nm. The film was then heated at 130°C for 10 minutes in a nitrogen gas atmosphere to form an emitting layer. (Cathode formation) The substrate on which the first layer was formed was placed in a deposition machine. -4 After reducing the pressure to 0.05 Pa or less, sodium fluoride was deposited on the light-emitting layer to a thickness of about 4 nm, and then aluminum was deposited on the sodium fluoride layer to a thickness of about 80 nm as a cathode. After the deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce light-emitting device D1. (Evaluation of light-emitting elements) EL light emission was observed by applying a voltage to the light-emitting element D1. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0303] <Examples D2 to D3 and Comparative Example CD1> Fabrication and Evaluation of Light-Emitting Devices D2, D3, and CD1 Light-emitting elements D2, D3, and CD1 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 3 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting elements D2, D3, and CD1. 2 Driving voltage [V] and CIE color The degree coordinates were measured.

[0304] The results of Examples D1 to D3 and Comparative Example CD1 are shown in Table 3. In Table 3, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D1 to D3 relative to the driving voltage [V] of the light-emitting element CD1.

[0305] [Table 3]

[0306] <Examples D4 to D5 and Comparative Example CD2> Fabrication and Evaluation of Light-Emitting Devices D4, D5, and CD2 Light-emitting elements D4, D5, and CD2 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 4 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting elements D4, D5, and CD2. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0307] The results of Examples D4 to D5 and Comparative Example CD2 are shown in Table 4. In Table 4, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D4 and D5 relative to the driving voltage [V] of the light-emitting element CD2.

[0308] [Table 4]

[0309] <Examples D6 to D7 and Comparative Example CD3> Fabrication and Evaluation of Light-Emitting Devices D6, D7, and CD3 Light-emitting devices D6, D7, and CD3 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 5 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D6, D7, and CD3.2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0310] The results for Examples D6 to D7 and Comparative Example CD3 are shown in Table 5. In Table 5, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D6 and D7 relative to the driving voltage [V] of the light-emitting element CD3.

[0311] [Table 5]

[0312] <Examples D8 to D10 and Comparative Example CD4> Fabrication and Evaluation of Light-Emitting Devices D8 to D10 and CD4 Light-emitting devices D8 to D10 and CD4 were fabricated in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 6 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D8 to D10 and CD4. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0313] The results for Examples D8 to D10 and Comparative Example CD4 are shown in Table 6. In Table 6, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D8 to D10 relative to the driving voltage [V] of the light-emitting element CD4.

[0314] [Table 6]

[0315] <Examples D11 to D12 and Comparative Example CD5> Fabrication and Evaluation of Light-Emitting Devices D11 to D12 and CD5 Light-emitting elements D11 to D12 and CD5 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 7 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting elements D11 to D12 and CD5. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0316] The results for Examples D11 and D12 and Comparative Example CD5 are shown in Table 7. In Table 7, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D11 and D12 relative to the driving voltage [V] of the light-emitting element CD5.

[0317] [Table 7]

[0318] Example D13 and Comparative Example CD6 Fabrication and Evaluation of Light-Emitting Devices D13 and CD6 Light-emitting devices D13 and CD6 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 8 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D13 and CD6. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0319] The results of Example D13 and Comparative Example CD6 are shown in Table 8. In Table 8, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting element D13 relative to the driving voltage [V] of the light-emitting element CD6.

[0320] [Table 8]

[0321] <Examples D14 to D17 and Comparative Example CD7> Fabrication and Evaluation of Light-Emitting Devices D14 to D17 and CD7 Light-emitting devices D14 to D17 and CD7 were fabricated in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 9 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D14 to D17 and CD7. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0322] The results of Examples D14 to D17 and Comparative Example CD7 are shown in Table 9. In Table 9, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D14 to D17 relative to the driving voltage [V] of the light-emitting element CD7.

[0323] [Table 9]

[0324] Example D18 and Comparative Example CD8 Fabrication and Evaluation of Light-Emitting Devices D18 and CD8 Light-emitting elements D18 and CD8 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 10 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D18 and CD8. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0325] The results of Example D18 and Comparative Example CD8 are shown in Table 10. In Table 10, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting element D18 relative to the driving voltage [V] of the light-emitting element CD8.

[0326] [Table 10]

[0327] <Examples D19 to D22 and Comparative Example CD9> Fabrication and Evaluation of Light-Emitting Devices D19 to D22 and CD9 Light-emitting elements D19 to D22 and CD9 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 11 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D19 to D22 and CD9. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0328] The results for Examples D19 to D22 and Comparative Example CD9 are shown in Table 11. In Table 11, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D19 to D22 relative to the driving voltage [V] of the light-emitting element CD9.

[0329] [Table 11]

[0330] Example D23 and Comparative Example CD10 Fabrication and Evaluation of Light-Emitting Devices D23 and CD10 Light-emitting devices D23 and CD10 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 12 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D23 and CD10. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0331] The results for Example D23 and Comparative Example CD10 are shown in Table 12. In Table 12, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting element D23 relative to the driving voltage [V] of the light-emitting element CD10.

[0332] [Table 12]

[0333] <Examples D24 to D26 and Comparative Example CD11> Fabrication and Evaluation of Light-Emitting Devices D24 to D26 and CD11 Light-emitting devices D24 to D26 and CD11 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 13 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D24 to D26 and CD11. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0334] The results for Examples D24 to D26 and Comparative Example CD11 are shown in Table 13. In Table 13, the driving voltage difference [V] indicates the difference in driving voltage [V] of light-emitting elements D24 to D26 relative to the driving voltage [V] of light-emitting element CD11.

[0335] [Table 13]

[0336] <Examples D27 to D29 and Comparative Example CD12> Fabrication and Evaluation of Light-Emitting Devices D27 to D29 and CD12 Light-emitting devices D27 to D29 and CD12 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 14 were used instead of "compound HM3 / compound B-G1 = 98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D27 to D29 and CD12. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0337] The results for Examples D27 to D29 and Comparative Example CD12 are shown in Table 14. In Table 14, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D27 to D29 relative to the driving voltage [V] of the light-emitting element CD12.

[0338] [Table 14]

[0339] <Examples D30 to D32 and Comparative Example CD13> Fabrication and Evaluation of Light-Emitting Devices D30 to D32 and CD13 Light-emitting devices D30 to D32 and CD13 were fabricated in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 15 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D30 to D32 and CD13. 2 Driving voltage [V] and The CIE chromaticity coordinates were measured.

[0340] The results for Examples D30 to D32 and Comparative Example CD13 are shown in Table 15. In Table 15, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting elements D30 to D32 relative to the driving voltage [V] of the light-emitting element CD13.

[0341] [Table 15]

[0342] Example D33 and Comparative Example CD14 Fabrication and Evaluation of Light-Emitting Devices D33 and CD14 Light-emitting devices D33 and CD14 were prepared in the same manner as in Example D1, except that the materials and composition ratios (mass%) listed in Table 16 were used instead of "compound HM3 / compound B-G1=98% by mass / 2% by mass" in Example D1 (formation of the light-emitting layer). EL light emission was observed by applying a voltage to the light-emitting devices D33 and CD14. 2 The driving voltage [V] and CIE chromaticity coordinates were measured.

[0343] The results of Example D33 and Comparative Example CD14 are shown in Table 16. In Table 16, the driving voltage difference [V] indicates the difference in driving voltage [V] of the light-emitting element D33 relative to the driving voltage [V] of the light-emitting element CD14.

[0344] [Table 16]

Claims

1. A composition comprising at least two compounds selected from the group consisting of a low molecular weight compound (b), a low molecular weight compound (h), and a polymer compound (H), and a solvent, At least one compound among the at least two compounds is the low molecular weight compound (b), the low molecular weight compound (b) is a low molecular weight compound having a heterocyclic skeleton (b) in which six or more rings are condensed, The heterocyclic skeleton (b) comprises a boron atom, a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and sp ３ and at least one carbon atom selected from the group consisting of carbon atoms in the fused ring, the low molecular weight compound (h) is a low molecular weight compound having a polycyclic aromatic hydrocarbon skeleton, When the composition contains the polymer compound (H), the low molecular weight compound (b) satisfies the requirements (i) and (ii), A composition, wherein when the composition contains the low molecular weight compound (h), the low molecular weight compound (b) satisfies requirement (ii). (i) The boron atom, the nitrogen atom, the oxygen atom, the sulfur atom, the selenium atom, and the sp atom contained in the fused ring of the heterocyclic skeleton (b). ３ The total number of carbon atoms is 4 or more. (ii) The number of nitrogen atoms contained in the fused ring of the heterocyclic skeleton (b) is 2 or more.

2. The composition according to claim 1 , wherein the low molecular weight compound (b) is a low molecular weight compound that satisfies the requirements (i) and (ii).

3. The composition according to claim 1, wherein the heterocyclic skeleton (b) is a heterocyclic skeleton represented by formula (b1-1): 【Chemistry 1】 [In the formula, Ring R ｂ１ , ring R ｂ２ , ring R ｂ３ , ring R ｂ４ and ring R ｂ５ each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X ｂ１ , X ｂ２ , X ｂ３ and X ｂ４ each independently represents an oxygen atom, a sulfur atom, a selenium atom, or —N(R ｘｂ )-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of the substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. However, X ｂ１ , X ｂ２ , X ｂ３ and X ｂ４ At least two of the following are -N(R ｘｂ )- is a group represented by the formula: R ｘｂ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group These groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X ｂ１ and ring R ｂ１ , X ｂ１ and ring R ｂ２ , X ｂ２ and ring R ｂ１ , X ｂ２ and ring R ｂ３ , X ｂ３ and ring R ｂ２ , X ｂ３ and ring R ｂ４ , X ｂ４ and ring R ｂ４ , X ｂ４ and ring R ｂ５ , ring R ｂ２ and ring R ｂ３ , ring R ｂ２ and ring R ｂ５ , and ring R ｂ３ and ring R ｂ５ may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded.

4. The X ｂ１ , the X ｂ２ , the X ｂ３ and the X ｂ４ each independently represents an oxygen atom, a sulfur atom, or —N(R ｘｂ 4. The composition according to claim 3, wherein the group is a group represented by the formula:

5. The sp contained in the low molecular weight compound having a heterocyclic skeleton represented by the formula (b1-1) ３ The composition of claim 3, wherein the total number of carbon atoms is 9 or more.

6. The composition according to claim 3, wherein the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) has at least one selected from the group consisting of an aryl group having three or more substituents, and a monovalent heterocyclic group having three or more substituents.

7. The composition according to claim 3, wherein the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1) is a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2). 【Chemistry 2】 [In the formula, Ring R ｂ１ , ring R ｂ２ , ring R ｂ３ , ring R ｂ４ , ring R ｂ５ , X ｂ２ and X ｂ４ represents the same meaning as above. Ring R Ｘｂ１ and ring R Ｘｂ２ each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ring R Ｘｂ１ and ring R ｂ１ , ring R Ｘｂ１ and ring R Ｘｂ２ , and ring R Ｘｂ２ and ring R ｂ４ may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or They may be different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.

8. At least one compound among the at least two compounds is the polymer compound (H), 2. The composition according to claim 1, wherein the polymer compound (H) is a polymer compound containing at least one structural unit selected from the group consisting of a structural unit represented by formula (X) and a structural unit represented by formula (Y): 【Transformation 3】 [In the formula, a Ｘ１ and a Ｘ２ each independently represents an integer of 0 or more. Ar Ｘ１ and Ar Ｘ３ each independently represents an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar Ｘ２ and Ar Ｘ４ each independently represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ｘ２ When a plurality of Ar are present, they may be the same or different. Ｘ４ When there are a plurality of groups, they may be the same or different. R Ｘ１ , R Ｘ２ and R Ｘ３ R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ｘ２ When there are a plurality of R, they may be the same or different. Ｘ３ When there are multiple groups, they may be the same or different. 【Chemistry 4】 [In the formula, Ar Ｙ１ represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded to each other, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded.]

9. At least one compound among the at least two compounds is the low molecular weight compound (h), The composition according to claim 1, wherein the low molecular weight compound (h) is a low molecular weight compound represented by formula (h-1): 【Transformation 5】 [In the formula, n １ｈ represents an integer of 0 or greater. Ar １ｈ is a hydrogen atom n directly bonded to an atom constituting the ring from a polycyclic aromatic hydrocarbon. １ｈ These groups may have a substituent. When a plurality of the substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. R １ｈ represents an aryl group, a monovalent heterocyclic group, or a substituted amino group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R １ｈ When a plurality of are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ar １ｈ and the substituent that R may have. １ｈ may be bonded to each other to form a ring together with the atoms to which they are bonded.

10. A composition comprising a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') and a solvent. 【Transformation 6】 [In the formula, Ring R ｂ１ , ring R ｂ２ , ring R ｂ３ , ring R ｂ４ and ring R ｂ５ each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X ｂ１ , X ｂ２ , X ｂ３ and X ｂ４ each independently represents an oxygen atom, a sulfur atom, a selenium atom, or —N(R ｘｂ )-, an alkylene group, or a cycloalkylene group, and these groups may have a substituent. When a plurality of the substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. However, X ｂ１ , X ｂ２ , X ｂ３ and X ｂ４ At least two of the following are -N(R ｘｂ )- is a group represented by the formula: R ｘｂ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group These groups may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. X ｂ１ and ring R ｂ１ , X ｂ１ and ring R ｂ２ , X ｂ２ and ring R ｂ１ , X ｂ２ and ring R ｂ３ , X ｂ３ and ring R ｂ２ , X ｂ３ and ring R ｂ４ , X ｂ４ and ring R ｂ４ , X ｂ４ and ring R ｂ５ , ring R ｂ２ and ring R ｂ３ , ring R ｂ２ and ring R ｂ５ , and ring R ｂ３ and ring R ｂ５ may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded. However, the sp contained in the low molecular weight compound having a heterocyclic skeleton represented by the formula (b1-1′) ３ The total number of carbon atoms is 9 or more, or the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1′) has at least one selected from the group consisting of an aryl group having three or more substituents and a monovalent heterocyclic group having three or more substituents.]

11. The composition according to claim 10, wherein the low molecular weight compound having a heterocyclic skeleton represented by formula (b1-1') is a low molecular weight compound having a heterocyclic skeleton represented by formula (b1-2'). 【Transformation 7】 [In the formula, Ring R ｂ１ , ring R ｂ２ , ring R ｂ３ , ring R ｂ４ , ring R ｂ５ , X ｂ２ and X ｂ４ represents the same meaning as above. Ring R Ｘｂ１ and ring R Ｘｂ２ each independently represents an aromatic hydrocarbon ring or a heterocyclic ring, and these rings may have a substituent. When a plurality of such substituents are present, they may be the same or different and may be bonded to each other to form a ring together with the atoms to which they are bonded. Ring R Ｘｂ１ and ring R ｂ１ , ring R Ｘｂ１ and ring R Ｘｂ２ , and ring R Ｘｂ２ and ring R ｂ４ may each independently bond directly or via a divalent or higher valent group which may have a substituent to form a ring. When a plurality of such substituents are present, they may be the same or different and may bond to each other to form a ring together with the atom to which they are bonded.

12. The composition according to any one of claims 1 to 11, further comprising at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, and an antioxidant.

13. A light-emitting device having an anode, a cathode, and an organic layer provided between the anode and the cathode, A light-emitting device, wherein the organic layer is a layer formed using the composition according to any one of claims 1 to 11.

Images