Organic electroluminescent element, electronic element, and electronic apparatus

Abstract

Provided is an organic EL element having excellent carrier balance and capable of achieving a low driving voltage, high efficiency, and a long service life. According to the present invention, disclosed is an organic EL element which comprises, in the stated sequence, an anode, a hole transport layer, an electron-blocking layer, a light-emitting layer, an electron transport layer, and a cathode. The electron-blocking layer contains a specific arylamine compound having a substituted phenyl group represented by general formula (II), and the light-emitting layer contains a specific arylamine compound having a condensed polycyclic aromatic group such as an indenophenanthryl group, an indenodibenzofuranyl group, or an indenodibenzothienyl group. In the formula, Ar4 and Ar5 represent an aryl group or a heteroaryl group, R1 represents a deuterium atom, an alkyl group, an alkyloxy group, an aryl group, a heteroaryl group, an aryloxy group, or the like, n represents an integer of 0 to 3, and * signifies a part for coupling with a structure in an arylamine compound.

Description

Organic electroluminescent elements, as well as electronic elements and electronic devices.

[0001] The present invention relates to self-light-emitting elements suitable for various display devices, particularly organic electroluminescent elements (hereinafter also referred to as "organic EL elements") using arylamine compounds, as well as electronic elements and electronic devices.

[0002] Organic EL elements have been the subject of active research due to their brightness, superior visibility, and ability to display clearly compared to liquid crystal elements. In 1987, C. W. Tang et al. of Eastman Kodak developed an element with a multilayer structure in which various materials are assigned different roles, paving the way for the practical application of organic EL elements (see Patent Documents 1 and 2). Since then, many improvements have been made toward the practical application of organic EL elements. The roles of each layer in the multilayer structure have been further subdivided, and by designing light-emitting elements with a multilayer structure in which an anode, hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, and cathode are sequentially arranged on a substrate, high efficiency and high durability have become achievable.

[0003] To improve the efficiency, durability, and other properties of organic EL elements, it is important to appropriately select the materials used in each organic layer of the stacked structure to create an element with excellent carrier balance. Organic EL elements emit light when charges injected from both electrodes recombine in the light-emitting layer. Therefore, efficiently transferring both holes and electrons to the light-emitting layer can increase luminescence efficiency. Furthermore, in the hole transport layer, selecting a material that not only has high hole injection properties but also high electron blocking properties that effectively block electrons injected from the cathode improves the probability of hole and electron recombination in the light-emitting layer, making it possible to confine the generated excitons within the light-emitting layer. As a result, high luminescence efficiency can be obtained. In other words, the role of the hole transport material is important, and there is a need for a hole transport material that has high hole injection properties, hole transport properties (i.e., hole mobility), and electron blocking properties, as well as excellent durability against electrons.

[0004] Regarding the lifespan of organic EL elements, the heat resistance and amorphous properties of the material are also important. The heat generated during the operation of the element causes thermal decomposition in materials with low heat resistance and crystallization of the thin film in materials with low amorphous properties. Since thermal decomposition and thin film crystallization degrade the element, the material used for the organic layer requires high heat resistance and good amorphous properties.

[0005] U.S. Patent No. 5,792,557, U.S. Patent No. 5,639,914, U.S. Patent No. 7,759,030, International Publication No. 2016 / 006629

[0006] Appl. Phys. Lett. , (USA), 2011, Volume 98, No. 8, 083302

[0007] Conventionally, N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (NPD) and various aromatic amine derivatives have been used as hole transport materials (see Patent Documents 1 and 2). However, although NPD has excellent hole transport properties, its glass transition temperature (Tg), an indicator of heat resistance, is low at 96°C, and it is known that under high-temperature conditions, crystallization degrades the device characteristics. Patent Document 3 reports on highly durable aromatic amine derivatives, but these were used as charge transport materials for electrophotographic photoreceptors, and there are no examples of their use as hole transport materials for organic EL devices. Furthermore, among aromatic amine derivatives, there are those with a mobility of 10 －３ cm ２ Although compounds with a Vs of 1 / Vs or higher and excellent hole transport properties are known (see Patent Documents 1 and 2), their electron blocking properties are insufficient, and some electrons pass through the light-emitting layer, resulting in insufficient luminescence efficiency.

[0008] Aromatic amine compounds have been proposed as compounds with improved properties such as heat resistance and hole injection capabilities (see, for example, Patent Document 4). However, devices using these compounds in the hole injection layer or hole transport layer have insufficient heat resistance and luminous efficiency.

[0009] As described above, in order to improve the device characteristics of organic EL devices, there is a need for materials with high electron blocking properties, thin film stability, and excellent heat resistance. Furthermore, by combining materials with excellent hole and electron injection and transport performance, thin film stability, and durability, there is a need for devices that can achieve excellent carrier balance, low drive voltage, high efficiency, and long lifespan.

[0010] The object of the present invention is to provide an organic EL element that achieves excellent carrier balance, low drive voltage, high efficiency, and long lifespan by appropriately combining the materials used. Another object of the present invention is to provide electronic elements and electronic devices using such organic EL elements.

[0011] To achieve the above objectives, the inventors focused on the fact that arylamine compounds have excellent hole injection and transport performance, thin film stability, and durability. They then diligently investigated various arylamine compounds and evaluated the characteristics of organic EL elements fabricated using these compounds. As a result, the inventors found that by using an arylamine compound having a specific structure as the material for the hole transport layer, holes injected from the anode side can be efficiently transported. Furthermore, they found that by using an arylamine compound having a specific structure different from the arylamine compound used as the material for the hole transport layer as the host material for the light-emitting layer, and combining it with the material for the hole transport layer, an organic EL element that can achieve low driving voltage, high efficiency, and long lifespan can be obtained. The present invention is based on these findings and is summarized below.

[0012] 1) An organic electroluminescent element having an anode, a hole transport layer, an electron blocking layer, an emissive layer, an electron transport layer, and a cathode in this order, wherein the electron blocking layer contains an arylamine compound represented by the following general formula (I), and the emissive layer contains a compound represented by the following general formula (III):

[0013]

[0014] In general formula (I), L １ ~L３ each independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group, and Ar １ ~Ar ３ each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, provided that one or two selected from Ar １ ~Ar ３ represents a substituted phenyl group represented by the following general formula (II), and at least one of L １ ~L ３ is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group,

[0015]

[0016] In the general formula (II), Ar ４ and Ar ５ each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, and R １ represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group, n represents an integer of 0 to 3, and when n is 2 or more, a plurality of R １ may be the same as or different from each other, and when n is 1 or more, R １ and the benzene ring to which this R １ is bonded, a plurality of adjacent R １ to each other, R １ and Ar ４ and R １ and Ar ５These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, and * represents L in general formula (I). １ ~L ３ This represents the connection point,

[0017]

[0018] In general formula (III), L ４ ~L ６ Each of these independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group, Ar ６ ~Ar ８ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, where Ar ６ ~Ar ８ At least one selected from represents a condensed polycyclic aromatic group represented by the following general formulas (IV-1) to (IV-8):

[0019]

[0020] In general formulas (IV-1) to (IV-8), X and Y are each independently -CR ５ R ６ -, -NR ７ -, -O-, or -S-, where in general formulas (IV-5) to (IV-8), at least one of X and Y is -CR ５ R ６ - or -O- represents R ２ ~R ４ Each of these independently represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group.２ ~R ４ is the R ２ ~R ４ Each of these may be bonded to a benzene ring, and may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, R ５ ~R ７ Each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ５ and R ６ The elements may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, where p represents an integer from 0 to 7, q represents an integer from 0 to 4, and r represents an integer from 0 to 5, and there are multiple R elements when p, q, and r are each independently 2 or more. ２ ~R ４ These may be the same or different from each other, and may be multiple adjacent Rs. ２ ~R ４ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, and * represents L in general formula (III). ４ ~L ６ This represents the connection point.

[0021] 2) In the above general formula (I), Ar １ L is a substituted phenyl group represented by the general formula (II), １The organic electroluminescent element according to 1), wherein the arylene group and / or heteroarylene group selected from the group consisting of substituted or unsubstituted phenylene group, biphenylylene group, terphenylylene group, naphthylene group, anthrylene group, phenanthrylene group, fluorenylene group, pyridinediyl group, thiophendiyl group, and dibenzofrangliyl group, and n in the general formula (II) is 0. 3) In the general formula (I), Ar １ is a substituted phenyl group represented by the general formula (II), and in the general formula (II), Ar ４ and Ar ５ The organic electroluminescent element according to 1) or 2), wherein each is independently an aryl group or heteroaryl group selected from the group consisting of substituted or unsubstituted phenyl groups, naphthyl groups, phenanthryl groups, and thienyl groups. 4) In the general formula (I), Ar １ is a substituted phenyl group represented by the general formula (II), and Ar ２ and Ar ３ At least one of the groups is an aryl group selected from the group consisting of a substituted or unsubstituted phenyl group, naphthyl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, and triphenylenyl group, and L is bonded to the aryl group. ２ and / or L ３ The organic electroluminescent element according to any one of 1) to 3), wherein each is independently a single bond or a combination of one or two arylene groups selected from the group consisting of phenylene groups, biphenylylene groups, and naphthylene groups, either substituted or unsubstituted.

[0022] 5) In the above general formula (I), L １ ~L ３ The organic electroluminescent element according to any one of 1) to 4), wherein each is independently a single bond, or a combination of one or two arylene groups selected from the group consisting of phenylene groups, biphenylylene groups, and naphthylene groups, and is either substituted or unsubstituted. 6) In the general formula (III), Ar ６However, it is a condensed polycyclic aromatic group represented by the general formula (IV-1), (IV-2), or (IV-3), L ４ However, the phenylene group is a single bond, substituted or unsubstituted, and in the general formula (IV-1), (IV-2), or (IV-3), X is -CR ５ R ６ - An organic electroluminescent element as described in any of 1) to 5). 7) In the general formula (III), Ar ６ However, it is a condensed polycyclic aromatic group represented by the general formula (IV-5) or (IV-6), L ４ However, it is a single bond or a substituted or unsubstituted phenylene group, and in the general formula (IV-5) or (IV-6), X is -CR ５ R ６ An organic electroluminescent element according to any of 1) to 5), wherein Y is -O-.

[0023] 8) An organic electroluminescent element according to any one of 1) to 7), wherein the electron blocking layer has a two-layer structure comprising a first electron blocking layer in contact with the hole transport layer and a second electron blocking layer in contact with the light-emitting layer, and the second electron blocking layer contains an arylamine compound represented by the general formula (I). 9) An organic electroluminescent element according to any one of 1) to 8), wherein the maximum wavelength of the emission spectrum when a DC voltage is applied to the organic electroluminescent element in air at 25°C is 600 nm or more and 700 nm or less. 10) An electronic element or electronic device having a pair of electrodes and at least two organic layers sandwiched between the pair of electrodes, wherein at least one of the organic layers contains an arylamine compound represented by the general formula (I), and the other organic layer in contact with the organic layer containing the arylamine compound represented by the general formula (I) contains a compound represented by the general formula (III).

[0024] According to the present invention, it is possible to provide an organic EL element that exhibits excellent carrier balance, low drive voltage, high efficiency, and long lifespan. Furthermore, according to the present invention, it is possible to provide electronic elements and electronic devices using such an organic EL element.

[0025] This is a schematic diagram showing the configuration of an organic EL element according to one embodiment of the present invention.

[0026] The organic EL element of the present invention comprises at least an anode, a hole transport layer, an electron blocking layer, an emissive layer, an electron transport layer, and a cathode in this order.

[0027] <Compound represented by general formula (I)> In the organic EL element of the present invention, the electron blocking layer contains the arylamine compound represented by the general formula (I).

[0028] In general formula (I), Ar １ ~Ar ３ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. In a "substituted or unsubstituted aryl group" or a "substituted or unsubstituted heteroaryl group," the aromatic ring constituting the "aryl group" or the aromatic heterocycle constituting the "heteroaryl group" may be a monocycle, a fused ring formed by the fusion of two or more rings, or a linked ring formed by the linkage of two or more rings via a single bond. It may also include a spirocycle formed by the linkage of two rings via a spiro atom. In a fused ring, linked ring, or spirocycle, the multiple rings may be identical or different, and may be a combination of identical or different aryl groups, a combination of identical or different heteroaryl groups, or a combination of an aryl group and a heteroaryl group. In a fused ring, the number of fused rings is, for example, 2 to 6, preferably 2 to 4. In a linked ring, the number of linked rings is, for example, 2 to 6, preferably 2 to 4. Examples of heteroatoms constituting the aromatic heterocycle include nitrogen atoms, oxygen atoms, and sulfur atoms. The number of carbon atoms in aromatic rings and aromatic heterocycles is, for example, 6-42, 6-30, 6-22, 6-18, 6-14, 6-10, 2-40, 2-30, or 2-18.

[0029] Ar １ ~Ar ３Specifically, the "aryl group" in "substituted or unsubstituted aryl group" as expressed in the above can be the following groups: aryl groups having 6 to 50 carbon atoms, preferably aryl groups having 6 to 30 carbon atoms, such as phenyl group, biphenylyl group, terphenylyl group, naphthyl group, anthryl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, indenyl group, pyrenyl group, perilenyl group, fluoranthenyl group, triphenylenyl group, and indenophenanthryl group.

[0030] Ar １ ~Ar ３ In the "substituted or unsubstituted heteroaryl group" represented by , the following groups can be specifically listed as "heteroaryl group": heteroaryl groups having 2 to 50 carbon atoms, preferably heteroaryl groups having 3 to 50 carbon atoms, such as pyridyl group, pyrimidinyl group, triazinyl group, furyl group, pyrrolyl group, thienyl group, quinolyl group, isoquinolyl group, benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalinyl group, benzimidazolyl group, pyrazolyl group, dibenzofuranyl group, dibenzothienyl group, naphthilidinyl group, phenanthrolinyl group, acridinyl group, carbolinyl group, indenodibenzofuranyl group, and indenodibenzothienyl group.

[0031] In general formula (I), L １ ~L ３ Each of these independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group. １ ~L ３ If it is a single bond, Ar １ ~Ar ３will be directly bonded to N (nitrogen atom) in the general formula (I), respectively. The aromatic ring constituting the "arylene group" or the aromatic heterocyclic ring constituting the "heteroarylene group" may be a monocyclic ring, a condensed ring in which two or more rings are condensed, or a linked ring in which two or more rings are linked via a single bond. Further, it may contain a spiro ring in which two rings are linked via a spiro atom. In the condensed ring, the linked ring, or the spiro ring, the plurality of rings may be the same or different, and may be a combination of the same or different arylene groups, a combination of the same or different heteroarylene groups, or a combination of an arylene group and a heteroarylene group. In the condensed ring, the number of condensed rings is, for example, 2 to 6, preferably 2 to 4. In the linked ring, the number of linked rings is, for example, 2 to 6, preferably 2 to 4. Examples of the heteroatom constituting the aromatic heterocyclic ring include a nitrogen atom, an oxygen atom, and a sulfur atom. The number of carbon atoms in the aromatic ring and the aromatic heterocyclic ring is, for example, 6 to 30, 6 to 22, 6 to 18, 6 to 14, 6 to 10, 2 to 40, 2 to 30, or 2 to 18.

[0032] L １ ~L ３ As the "arylene group" in the "substituted or unsubstituted arylene group" represented by, the above Ar １ ~Ar ３ The groups obtained by removing one hydrogen atom from the groups exemplified as the "aryl group" represented by can be mentioned respectively. Specifically, the following groups can be mentioned. Arylene groups having 6 to 50 carbon atoms, preferably arylene groups having 6 to 30 carbon atoms, such as a phenylene group, a biphenylylene group, a terphenylylene group, a naphthylene group, an anthrylene group, a phenanthrylene group, a fluorenylene group, a spirobifluorenylene group, an indenylene group, a pyrenylene group, a perylenylene group, a fluoranthenylene group, and a triphenylenylene group.

[0033] L １ ~L ３ As the "heteroarylene group" in the "substituted or unsubstituted heteroarylene group" represented by, the above Ar １ ~Ar ３Examples of the "heteroaryl group" represented by include groups obtained by removing one hydrogen atom from each of the groups exemplified above. Specifically, the following groups can be mentioned. Pyridinediyl group, pyrimidinediyl group, triazinediyl group, furandiyl group, pyrrolediyl group, thiophenediyl group, quinolinediyl group, isoquinolinediyl group, benzofurandiyl group, benzothiophenediyl group, indolediyl group, carbazolediyl group, benzoxazolediyl group, benzothiazolediyl group, quinoxalinediyl group, benzoimidazolediyl group, pyrazolediyl group, dibenzofurandiyl group, dibenzothiophenediyl group, naphthyridinediyl group, phenanthrolinediyl group, acridinediyl group, carbolinediyl group, imidazopyridinediyl group, oxazolopyridinediyl group, oxazolopyrazinediyl group, and quinazolinediyl group, etc., heteroarylene groups having 2 to 50 carbon atoms, preferably heteroarylene groups having 2 to 20 carbon atoms.

[0034] In general formula (I), Ar １ ~Ar ３ One or two selected from represent a substituted phenyl group represented by the general formula (II), and L １ ~L ３ At least one of is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group (that is, not a single bond). In addition, when the above Ar １ ~Ar ３ is a "substituted or unsubstituted aryl group" or a "substituted or unsubstituted heteroaryl group", examples of the aryl group or the heteroaryl group include the groups exemplified above. However, when the groups exemplified above correspond to the substituted phenyl group represented by the general formula (II), that group shall be one or two substituted phenyl groups represented by the general formula (II) selected from Ar １ ~Ar ３ For example, the terphenyl group exemplified as the aryl group in the "substituted or unsubstituted aryl group" is a substituted phenyl group represented by the general formula (II). Therefore, "Ar １ ~Ar ３In the statement, "one or two selected from are substituted phenyl groups represented by the general formula (II)," the phrase "substituted phenyl groups represented by the general formula (II)" means including the terpheniryl group, for example, Ar １ ~Ar ３ Compounds in which all of the groups are terpheniryl groups are not included in general formula (I).

[0035] In general formula (II), Ar ４ and Ar ５ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. １ This represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group.

[0036] Ar ４ Ar ５ , and R １ In the "substituted or unsubstituted aryl group" or "substituted or unsubstituted heteroaryl group" represented by , the "aryl group" or "heteroaryl group" is Ar in general formula (I). １ ~Ar ３ The explanation for "aryl group" or "heteroaryl group" represented by the same notation can be applied similarly.

[0037] R １The terms "substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms", "substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms", "substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms", "substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms", "substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms", or "substituted or unsubstituted aryloxy group" specifically include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, Alkyl groups such as tyl groups and n-hexyl groups; cycloalkyl groups such as cyclopentyl groups, cyclohexyl groups, 1-adamantyl groups, and 2-adamantyl groups; alkenyl groups such as vinyl groups, allyl groups, isopropenyl groups, and 2-butenyl groups; alkyloxy groups such as methyloxy groups, ethyloxy groups, n-propyloxy groups, isopropyloxy groups, n-butyloxy groups, tert-butyloxy groups, n-pentyloxy groups, and n-hexyloxy groups; cyclopentyloxy groups Examples of cycloalkyloxy groups include cyclohexyloxy, cycloheptyloxy, cyclooctyloxy, 1-adamantyloxy, and 2-adamantyloxy groups; and aryloxy groups having 6 to 50 carbon atoms, such as phenyloxy, biphenylyloxy, terphenylyloxy, naphthyloxy, anthracenyloxy, phenantrenyloxy, fluorenyloxy, indenyloxy, pyrenyloxy, and perilennyloxy groups.

[0038] In general formula (II), n is R １ This represents the number of elements, and is an integer between 0 and 3. If n is 2 or greater, there are multiple elements R. １These can be the same or different from each other. Also, if n is 1 or greater, R １ and R １ A benzene ring to which is bonded, and multiple adjacent Rs bonded to the benzene ring. １ Allies, R １ and Ar ４ , and R １ and Ar ５ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms, forming a ring. * is L in general formula (I). １ ~L ２ This represents the connection point.

[0039] In general formulas (I) and (II), Ar １ ~Ar ５ , R １ , and L １ ~L ３Each of the above groups represented by may have one or more substituents. Specifically, "substituents" include: deuterium atoms; cyano groups, nitro groups; halogen atoms such as fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms; silyl groups such as trimethylsilyl groups and triphenylsilyl groups; linear or branched alkyl groups having 1 to 6 carbon atoms such as methyl groups, ethyl groups, and propyl groups; linear or branched alkyloxy groups having 1 to 6 carbon atoms such as methyloxy groups, ethyloxy groups, and propyloxy groups; alkenyl groups such as vinyl groups and allyl groups; aryloxy groups such as phenyloxy groups and tolyloxy groups; and arylalkyloxy groups such as benzyloxy groups and phenethyloxy groups. Examples of aryl groups include phenyl, biphenylyl, terphenylyl, naphthyl, anthyl, phenanthryl, fluorenyl, spirobifluorenyl, indenyl, pyrenyl, perilenyl, fluoranthenyl, and triphenylenyl groups; and heteroaryl groups such as pyridyl, furyl, pyrrolyl, thienyl, quinolyl, isoquinolyl, benzofuranyl, benzothienyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, quinoxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothienyl, and carboninyl groups. These substituents may further have one or more of the substituents exemplified above. Furthermore, these substituents and each of the groups substituted by them, or multiple substituents adjacent to each other, may be bonded or fused via single bonds, substituted or unsubstituted methylene groups, nitrogen atoms, oxygen atoms, or sulfur atoms to form a ring.

[0040] In general formula (I), Ar １ ~Ar ３The substituted or unsubstituted aryl group or substituted or unsubstituted heteroaryl group represented by is preferably independently selected from the group consisting of substituted or unsubstituted phenyl group, biphenylyl group, terphenylyl group, naphthyl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, triphenylenyl group, pyridyl group, pyrimidinyl group, triazinyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, dibenzofuranyl group, dibenzothienyl group, and phenanthrolinyl group; more preferably selected from the group consisting of substituted or unsubstituted phenyl group, biphenylyl group, terphenylyl group, naphthyl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, triphenylenyl group, pyridyl group, benzoxazolyl group, and dibenzofuranyl group; and particularly preferably selected from the group consisting of substituted or unsubstituted phenyl group, naphthyl group, phenanthryl group, and fluorenyl group.

[0041] In general formula (I), Ar １ ~Ar ３In the "substituted or unsubstituted biphenylyl group" represented by a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, the "biphenylyl group" is preferably a 1,1'-biphenyl-3-yl group or a 1,1'-biphenyl-4-yl group, and more preferably a 1,1'-biphenyl-4-yl group. In "substituted or unsubstituted terpheniryl groups," the "terpheniryl group" is preferably a 1,1':4',1''-terphenyl-4-yl group, a 1,1':4',1''-terphenyl-3-yl group, a 1,1':4',1''-terphenyl-2'-yl group, a 1,1':3',1''-terphenyl-4-yl group, or a 1,1':2',1''-terphenyl-4-yl group, and more preferably a 1,1':4',1''-terphenyl-4-yl group or a 1,1':4',1''-terphenyl-2'-yl group. In "substituted or unsubstituted naphthyl groups," the "naphthyl group" is preferably a 1-naphthyl group or a 2-naphthyl group. In "substituted or unsubstituted phenanthryl groups," the "phenanthryl group" is preferably a 2-phenanthryl group or a 9-phenanthryl group, and more preferably a 9-phenanthryl group. In "substituted or unsubstituted fluorenyl groups," the "fluorenyl group" is preferably a 2-fluorenyl group, a 3-fluorenyl group, or a 4-fluorenyl group, and more preferably a 2-fluorenyl group. In "substituted or unsubstituted spirobifluorenyl groups," the "spirobiofluorenyl group" is preferably a 2-spirobiofluorenyl group, a 3-spirobiofluorenyl group, or a 4-spirobiofluorenyl group, and more preferably a 2-spirobiofluorenyl group. In "substituted or unsubstituted triphenylenyl groups," the "triphenylenyl group" is preferably a 2-triphenylenyl group. In "substituted or unsubstituted pyridyl group," the "pyridyl group" is preferably a 2-pyridyl group or a 3-pyridyl group, with the 3-pyridyl group being more preferred. In "substituted or unsubstituted benzoxazolyl group," the "benzoxazolyl group" is preferably a 2-benzoxazolyl group.In "substituted or unsubstituted dibenzofuranyl group," the "dibenzofuranyl group" is preferably a 1-dibenzofuranyl group, a 2-dibenzofuranyl group, or a 3-dibenzofuranyl group, with a 1-dibenzofuranyl group or a 2-dibenzofuranyl group being more preferred.

[0042] In general formula (I), L １ ~L ３ If L is a "substituted or unsubstituted arylene group" or a "substituted or unsubstituted heteroarylene group", １ ~L ３ The group may be one, two, or three combinations selected from "substituted or unsubstituted arylene groups" and "substituted or unsubstituted heteroarylene groups." Specifically, the "substituted or unsubstituted arylene group" or "substituted or unsubstituted heteroarylene group" is preferably one, two, or three combinations of substituted or unsubstituted arylene groups and / or heteroarylene groups selected from the group consisting of phenylene group, biphenylylene group, terphenylylene group, naphthylene group, anthreylene group, phenanthrylene group, fluorenylene group, spirobifluorenylene group, pyridinediyl group, pyrimidinediyl group, triazinediyl group, franziyl group, pyrrolediyl group, thiophenediyl group, dibenzofranziyl group, dibenzothiophenediyl group, and phenanthrolinediyl group. In other words, it is preferable that the arylene group or the heteroarylene group be one of the above, a combination of two or three identical or different arylene groups, a combination of two or three identical or different heteroarylene groups, or a combination of two or three arylene groups and the heteroarylene group. It is more preferable that the arylene group and / or heteroarylene group be one or two combinations selected from the group consisting of substituted or unsubstituted phenylene groups, biphenylene groups, naphthylene groups, pyridinediyl groups, and thiophenediyl groups, and it is particularly preferable that the arylene group be one or two combinations selected from the group consisting of unsubstituted phenylene groups, biphenylene groups, and naphthylene groups.

[0043] In general formula (I), L １ ~L ３ Preferably, each of these is a combination of one, two, or three arylene groups and / or heteroarylene groups selected from the group consisting of single-bonded, substituted, or unsubstituted phenylene groups, biphenylylene groups, terphenylylene groups, naphthylene groups, anthrylene groups, phenanthrylene groups, fluorenylene groups, spirobifluorenylene groups, pyridinediyl groups, pyrimidinediyl groups, triazinediyl groups, franziyl groups, pyrrolediyl groups, thiophenediyl groups, dibenzofranziyl groups, dibenzothiophenediyl groups, and phenanthrolinediyl groups, and is preferably a combination of one, two, or three arylene groups and / or heteroarylene groups selected from the group consisting of single-bonded, substituted, or unsubstituted phenylene groups, biphenylylene groups, terphenylylene groups, naphthylene groups, anthrylene groups, and phenanthrolinediyl groups. It is more preferable that the arylene group and / or heteroarylene group selected from the group consisting of nanthrylene, fluorenylene, pyridinediyl, thiophenediyl, and dibenzofranziyl groups be one or two combinations of these groups; it is even more preferable that the arylene group and / or heteroarylene group selected from the group consisting of single-bonded, substituted, or unsubstituted phenylene, biphenylylene, naphthylene, pyridinediyl, and thiophenediyl groups be one or two combinations of these groups; and it is particularly preferable that the arylene group and / or heteroarylene group selected from the group consisting of single-bonded, substituted, or unsubstituted phenylene, biphenylylene, and naphthylene groups be one or two combinations of these groups.

[0044] In general formula (I), L １ ~L ３In the "substituted or unsubstituted phenylene group" as a substituted or unsubstituted heteroarylene group represented by , the "phenylene group" is preferably a 1,3-phenylene group or a 1,4-phenylene group, and more preferably a 1,4-phenylene group. In the "substituted or unsubstituted biphenylylene group", the "biphenylylene group" is preferably a 1,1'-biphenyl-4,3'-diyl group or a 1,1'-biphenyl-4,4'-diyl group, and more preferably a 1,1'-biphenyl-4,4'-diyl group. In the "substituted or unsubstituted naphthylene group", the "naphthylene group" is preferably a 1,3-naphthylene group or a 2,6-naphthylene group, and more preferably a 1,3-naphthylene group. In the "substituted or unsubstituted fluorenylene group," the "fluorenylene group" is preferably a 2,7-fluorenylene group or a 2,9-fluorenylene group. In the "substituted or unsubstituted pyridinediyl group," the "pyridinediyl group" is preferably a 3,5-pyridinediyl group or a 2,5-pyridinediyl group, and more preferably a 3,5-pyridinediyl group. In the "substituted or unsubstituted thiophenediyl group," the "thiophenediyl group" is preferably a 2,5-thiophenediyl group or a 3,5-thiophenediyl group, and more preferably a 2,5-thiophenediyl group.

[0045] In general formula (I), Ar １ ~Ar ３ One or two selected from are substituted phenyl groups represented by the general formula (II), but Ar １ ~Ar ３ Preferably, one of the selected groups is a substituted phenyl group represented by the general formula (II). For example, in general formula (I), Ar １ If is a substituted phenyl group represented by the general formula (II), then Ar ２ and Ar ３Preferably, at least one of the groups is an aryl group selected from the group consisting of a substituted or unsubstituted phenyl group, naphthyl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, and triphenylenyl group, and more preferably an aryl group selected from the group consisting of a substituted or unsubstituted phenyl group, naphthyl group, phenanthryl group, and fluorenyl group. However, Ar ２ and Ar ３ At least one of these groups is a group not included in the substituted phenyl group represented by the general formula (II). Also, Ar ２ and Ar ３ L bonded to at least one of the aryl groups ２ and / or L ３ (That is, L ２ , L ３ , or L ２ and L ３ Each of these groups is preferably a combination of one or two arylene groups selected from the group consisting of a single bond, a substituted or unsubstituted phenylene group, a biphenylylene group, and a naphthylene group, and more preferably a single bond, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylylene group.

[0046] As described above, L bonded to the substituted phenyl group represented by the general formula (II) １ ~L ３ At least one of them is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group (i.e., not a single bond), but is bonded to the substituted phenyl group. １ ~L ３It is preferable that the substituted phenyl group is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group. The "substituted or unsubstituted arylene group" or "substituted or unsubstituted heteroarylene group" bonded to the substituted phenyl group is preferably a combination of one, two, or three groups independently selected from the group consisting of substituted or unsubstituted phenylene group, biphenylylene group, terphenylylene group, naphthylene group, anthreylene group, phenanthrylene group, fluorenylene group, spirobifluorenylene group, pyridinediyl group, pyrimidinediyl group, triazinediyl group, thiophenediyl group, dibenzofranziyl group, dibenzothiophenediyl group, and phenanthrolinediyl group. It is more preferable that the group is one or two selected from the group consisting of substituted or unsubstituted phenylene groups, biphenylylene groups, terphenylylene groups, naphthylene groups, anthrylene groups, phenanthrylene groups, fluorenylene groups, pyridinediyl groups, thiophenediyl groups, and dibenzofranziyl groups, and it is even more preferable that the group is one or two selected from the group consisting of substituted or unsubstituted phenylene groups, biphenylylene groups, pyridinediyl groups, and thiophenediyl groups, and it is particularly preferable that the group is an unsubstituted phenylene group or an unsubstituted biphenylylene group.

[0047] L bonded to the substituted phenyl group represented by the general formula (II) １ ~L ３In the above, the "phenylene group" in the "substituted or unsubstituted phenylene group" is preferably a 1,3-phenylene group or a 1,4-phenylene group, and more preferably a 1,4-phenylene group, as a substituted or unsubstituted heteroarylene group. The "biphenylene group" in the "substituted or unsubstituted biphenylylene group" is preferably a 1,1'-biphenyl-4,3'-diyl group or a 1,1'-biphenyl-4,4'-diyl group, and more preferably a 1,1'-biphenyl-4,4'-diyl group. The "fluorenylene group" in the "substituted or unsubstituted fluorenylene group" is preferably a 2,7-fluorenylene group or a 2,9-fluorenylene group. In the "substituted or unsubstituted pyridinediyl group," the "pyridinediyl group" is preferably a 3,5-pyridinediyl group or a 2,5-pyridinediyl group, and more preferably a 3,5-pyridinediyl group. In the "substituted or unsubstituted thiophenediyl group," the "thiophenediyl group" is preferably a 2,5-thiophenediyl group or a 3,5-thiophenediyl group, and more preferably a 2,5-thiophenediyl group.

[0048] In general formula (II), Ar ４ and Ar ５ The substituted or unsubstituted aryl group or substituted or unsubstituted heteroaryl group represented by is preferably independently selected from the group consisting of substituted or unsubstituted phenyl, biphenylyl, naphthyl, anthryl, phenanthryl, pyridyl, thienyl, benzoxazolyl, carbazolyl, and dibenzofuranyl groups; more preferably selected from the group consisting of substituted or unsubstituted phenyl, biphenylyl, naphthyl, phenanthryl, and thienyl groups; even more preferably selected from the group consisting of substituted or unsubstituted phenyl, naphthyl, phenanthryl, and thienyl groups; and particularly preferably an unsubstituted phenyl group or an unsubstituted naphthyl group.

[0049] In general formula (II), R １The group is preferably a cyano group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aryloxy group; more preferably a cyano group, a substituted or unsubstituted linear alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted phenyloxy group; and particularly preferably a cyano group, an unsubstituted phenyl group, an unsubstituted phenanthryl group, or an unsubstituted phenyloxy group.

[0050] In general formula (II), n is preferably 0 to 2, more preferably 0 or 1, and particularly preferably 0.

[0051] In general formulas (I) and (II), Ar １ ~Ar ５ , R １ , and L １ ~L ３ When each of the above groups represented by has one or more substituents, the substituents are preferably a deuterium atom, a cyano group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted aryloxy group, or a substituted or unsubstituted heteroaryl group, more preferably selected from the group consisting of a deuterium atom, a cyano group, a substituted or unsubstituted linear alkyl group having 1 to 4 carbon atoms, and substituted or unsubstituted phenyl group, biphenylyl group, terphenylyl group, naphthyl group, phenanthryl group, phenyloxy group, and carbazolyl group, and even more preferably selected from the group consisting of a deuterium atom, a cyano group, and unsubstituted phenyl group, biphenylyl group, terphenylyl group, naphthyl group, phenanthryl group, and phenyloxy group.

[0052] Specific examples of compounds represented by general formula (I) are given below. However, the compounds represented by general formula (I) that can be used in the present invention should not be interpreted as being limited by the following specific examples. Also, in the chemical structural formulas below, hydrogen atoms ( １ The notation H) is omitted, and the deuterium atom (２ H) is written as "D".

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059] Compounds represented by general formula (I) can be synthesized by applying known coupling reactions and appropriately selecting known reaction conditions. For details of the reaction, refer to the synthesis examples described later. Furthermore, the compounds represented by general formula (I) can be purified by known methods such as column chromatography, adsorption purification using silica gel, activated carbon, or activated clay, recrystallization or crystallization with solvents, and sublimation purification. Compound identification can be performed, for example, by NMR analysis or mass spectrometry (MS).

[0060] Examples of physical properties of compounds represented by general formula (I) include the melting point, glass transition temperature (Tg), and HOMO energy level. It is preferable to measure the glass transition temperature and HOMO energy level. The melting point serves as an indicator of vapor deposition properties, the glass transition temperature (Tg) serves as an indicator of the stability of the thin film state, and the HOMO energy level serves as an indicator of hole injection properties, hole transport properties, or electron blocking properties.

[0061] The melting point and glass transition point of the powder can be measured using a high-sensitivity differential scanning calorimeter (e.g., Bruker AXS, model: DSC3100SA). The HOMO energy level can be measured for a 100 nm thin film fabricated on a silicon substrate using an ionization potential analyzer (e.g., Sumitomo Heavy Industries, Ltd., model: PYS-202).

[0062] <Compound represented by general formula (III)> In the organic EL element of the present invention, the light-emitting layer contains the compound represented by the general formula (III). In general formula (III), L ４ ~L ６ Each of these independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group. Also, Ar ６ ~Ar ８ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. ４ ~L ６ If it is a single bond, Ar ６ ~Ar ８ However, each of these will bond directly to the nitrogen atom (N) in general formula (III).

[0063] L ４ ~L ６ The "arylene group" or "heteroarylene group" in the "substituted or unsubstituted arylene group" or "substituted or unsubstituted heteroarylene group" represented by the general formula (I) is L １ ~L ３ The explanation of the "arylene group" or "heteroarylene group" represented by the same formula can be applied in the same way.

[0064] Ar ６ ~Ar ８ The "aryl group" or "heteroaryl group" in the "substituted or unsubstituted aryl group" or "substituted or unsubstituted heteroaryl group" represented by the general formula (I) is Ar １ ~Ar ３ The explanation for "aryl group" or "heteroaryl group" represented by the same notation can be applied similarly.

[0065] Ar ６ ~Ar ８ At least one selected from the above represents a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8). In the general formulas (IV-1) to (IV-8), X and Y are each independently -CR ５ R ６ -, -NR ７-, -O-, or -S-, and at least one of X and Y is -CR ５ R ６ It represents - or -O-. Note that -CR ５ R ６ - is R ５ and R ６ Represents a methylene group substituted by -NR ７ - is R ７ R represents a nitrogen atom (imino group) substituted by -O- represents an oxygen atom (ether bond), and -S- represents a sulfur atom (sulfide bond). ５ ~R ７ Each of these independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ５ and R ６ These elements may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring.

[0066] In general formulas (IV-1) to (IV-8), R ２ ~R ４ Each of these independently represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ２ ~R ４is the R ２ ~R ４ Each of these may be bonded to a benzene ring, and may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring.

[0067] R ２ ~R ７ In the expressions "substituted or unsubstituted linear or branched alkyl groups having 1 to 6 carbon atoms", "substituted or unsubstituted cycloalkyl groups having 5 to 10 carbon atoms", "substituted or unsubstituted linear or branched alkenyl groups having 2 to 6 carbon atoms", "substituted or unsubstituted linear or branched alkyloxy groups having 1 to 6 carbon atoms", "substituted or unsubstituted cycloalkyloxy groups having 5 to 10 carbon atoms", "substituted or unsubstituted aryl groups", "substituted or unsubstituted heteroaryl groups", or "substituted or unsubstituted aryloxy groups", the "linear or branched alkyl groups having 1 to 6 carbon atoms", "cycloalkyl groups having 5 to 10 carbon atoms", "linear or branched alkenyl groups having 2 to 6 carbon atoms", "linear or branched alkyloxy groups having 1 to 6 carbon atoms", "cycloalkyloxy groups having 5 to 10 carbon atoms", "aryl groups", "heteroaryl groups", or "aryloxy groups" in general formula (II) are as follows: １ The descriptions of each of the above-mentioned groups represented by can be applied similarly.

[0068] In general formulas (III) and (IV-1) to (IV-8), L ４ ~L ６ Ar ６ ~Ar ８ , and R ２ ~R ７ Each of the above groups represented by may have one or more substituents, and the same explanation for "substituents" in general formulas (I) and (II) can be applied to them.

[0069] In general formula (III), L ４ ~L ６ If L is a "substituted or unsubstituted arylene group" or a "substituted or unsubstituted heteroarylene group",４ ~L ６ The group may be one, two, or three combinations selected from "substituted or unsubstituted arylene groups" and "substituted or unsubstituted heteroarylene groups." Specifically, the "substituted or unsubstituted arylene group" or "substituted or unsubstituted heteroarylene group" is preferably one, two, or three combinations of substituted or unsubstituted arylene groups and / or heteroarylene groups selected from the group consisting of phenylene, biphenylylene, naphthylene, pyridinediyl, pyrimidinediyl, triazinediyl, and quinolinediyl groups. That is, it is preferably one of the arylene group or the heteroarylene group, a combination of two or three identical or different arylene groups, a combination of two or three identical or different heteroarylene groups, or a combination of the arylene group and the heteroarylene group. Furthermore, it is more preferable that the group consists of one or two substituted or unsubstituted phenylene groups, naphthylene groups, and pyridinediyl groups, and it is particularly preferable that the group is a substituted or unsubstituted phenylene group.

[0070] In general formula (III), L ４ ~L ６ In the "substituted or unsubstituted phenylene group" as a substituted or unsubstituted heteroarylene group represented by , the "phenylene group" is preferably a 1,3-phenylene group or a 1,4-phenylene group, and more preferably a 1,4-phenylene group. In the "substituted or unsubstituted naphthylene group", the "naphthylene group" is preferably a 2,6-naphthylene group. In the "substituted or unsubstituted pyridinediyl group", the "pyridinediyl group" is preferably a 2,3-pyridinediyl group or a 2,5-pyridinediyl group.

[0071] In general formula (III), L ４ ~L ６Preferably, each of these is independently one, two, or three combinations of arylene groups and / or heteroarylene groups selected from the group consisting of single-bonded, substituted, or unsubstituted phenylene groups, biphenylylene groups, naphthylene groups, pyridinediyl groups, pyrimidinediyl groups, triazinediyl groups, and quinolinediyl groups, and also, substituted, or unsubstituted arylene groups and / or It is more preferable that the group is a combination of one or two heteroarylene groups, more preferably a combination of one or two selected from the group consisting of single-bonded, substituted or unsubstituted phenylene groups, naphthylene groups, and pyridinediyl groups, and even more preferably a combination of one or two arylene groups selected from the group consisting of single-bonded, substituted or unsubstituted phenylene groups, and particularly preferably a single-bonded, substituted or unsubstituted phenylene group.

[0072] In general formula (III), Ar ６ ~Ar ８The substituted or unsubstituted aryl group or substituted or unsubstituted heteroaryl group represented by is independently a substituted or unsubstituted phenyl group, biphenylyl group, terphenylyl group, naphthyl group, anthryl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, indenyl group, indenophenanthryl group, pyridyl group, pyrimidinyl group, triazinyl group, quinolyl group, benzofuranyl group, benzothienyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzothiazolyl group, quinoxalinyl group, benzimidazolyl group, dibenzofuranyl group, dibenzothienyl group, phenanthrolinyl group, indenodibenzofuranyl group, and indenodibenzothi It is preferable to select from the group consisting of enyl groups, more preferably to select from the group consisting of substituted or unsubstituted phenyl groups, biphenylyl groups, naphthyl groups, phenanthryl groups, fluorenyl groups, spirobifluorenyl groups, indenyl groups, indenophenanthryl groups, carbazolyl groups, dibenzofuranyl groups, dibenzothienyl groups, indenodibenzofuranyl groups, and indenodibenzothienyl groups, and even more preferably to select from the group consisting of substituted or unsubstituted phenyl groups, biphenylyl groups, naphthyl groups, fluorenyl groups, indenophenanthryl groups, carbazolyl groups, dibenzofuranyl groups, indenodibenzofuranyl groups, and indenodibenzothienyl groups.

[0073] Ar ６ ~Ar ８In the "substituted or unsubstituted phenyl group" as a substituted or unsubstituted aryl group or substituted or unsubstituted heteroaryl group, the "phenyl group" is preferably an unsubstituted phenyl group or a 4-substituted phenyl group. As substituents on the 4-substituted phenyl group, linear or branched alkyl groups having 1 to 4 carbon atoms are preferred. In the "substituted or unsubstituted biphenylyl group", the "biphenylyl group" is preferably a 1,1'-biphenyl-3-yl group or a 1,1'-biphenyl-4-yl group, and more preferably a 1,1'-biphenyl-4-yl group. In the "substituted or unsubstituted naphthyl group", the "naphthyl group" is preferably a 1-naphthyl group or a 2-naphthyl group, and more preferably a 2-naphthyl group. In the "substituted or unsubstituted phenanthryl group", the "phenanthryl group" is preferably a 9-phenanthryl group. In "substituted or unsubstituted fluorenyl groups," the "fluorenyl group" is preferably a 1-fluorenyl group or a 2-fluorenyl group, and more preferably a 2-fluorenyl group. In "substituted or unsubstituted spirobifluorenyl groups," the "spirobiofluorenyl group" is preferably a 1-spirobiofluorenyl group or a 2-spirobiofluorenyl group, and more preferably a 2-spirobiofluorenyl group. In "substituted or unsubstituted indenyl groups," the "indenyl group" is preferably a 6-indenyl group. In "substituted or unsubstituted indenophenanthryl groups," the "indenophenanthryl group" is preferably an indenophenanthryl group represented by the general formulas (IV-1) to (IV-4). In "substituted or unsubstituted dibenzofuranyl groups," the "dibenzofuranyl group" is preferably a 1-dibenzofuranyl group or a 2-dibenzofuranyl group. In the "substituted or unsubstituted dibenzothienyl group," the "dibenzothienyl group" is preferably a 1-dibenzothienyl group or a 2-dibenzothienyl group. In the "substituted or unsubstituted carbazolyl group," the "carbazolyl group" is preferably a 1-carbazolyl group, a 2-carbazolyl group, or a 9-carbazolyl group, and more preferably a 9-carbazolyl group.In "substituted or unsubstituted indenodibenzofuranyl group" or "substituted or unsubstituted indenodibenzothienyl group," the "indenodibenzofuranyl group" or "indenodibenzothienyl group" is preferably an indenodibenzofuranyl group or indenodibenzothienyl group represented by the general formulas (IV-5) to (IV-8).

[0074] In general formula (III), Ar ６ ~Ar ８ At least one selected from is a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8), and Ar ６ ~Ar ８ Preferably, one or two selected from are condensed polycyclic aromatic groups represented by the general formulas (IV-1) to (IV-8), and Ar ６ ~Ar ８ It is more preferable that one of the selected groups is a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8). ６ ~Ar ８ If is a "substituted or unsubstituted aryl group" or a "substituted or unsubstituted heteroaryl group", the aryl group or heteroaryl group may be the groups exemplified above, but if the group exemplified above corresponds to a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8), then that group is Ar ６ ~Ar ８ It is a condensed polycyclic aromatic group represented by at least one (IV-1) to (IV-8) selected from the above. For example, "Ar ６ ~Ar ８ The statement "any one selected from is a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8)" means, for example, Ar ６ This is a condensed polycyclic aromatic group represented by the general formula (IV-1), and Ar ７ and Ar ８ However, this means that the group is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group other than the condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8) above.

[0075] In general formula (III), for example, Ar ６ If is a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8), then Ar ７ and Ar ８ At least one of, preferably Ar ７ and Ar ８ It is preferable that both are substituted or unsubstituted aryl or heteroaryl groups selected from the group consisting of phenyl, naphthyl, phenanthryl, fluorenyl, spirobifluorenyl, dibenzofuranyl, and carbazolyl groups (these groups are not condensed polycyclic aromatic groups represented by the general formulas (IV-1) to (IV-8) above), and more preferably substituted or unsubstituted aryl or heteroaryl groups selected from the group consisting of phenyl, naphthyl, fluorenyl, dibenzofuranyl, and carbazolyl groups (these groups are not condensed polycyclic aromatic groups represented by the general formulas (IV-1) to (IV-8) above). Also, Ar ７ and Ar ８ At least one of, preferably Ar ７ and Ar ８ L that is attached to the aryl group or heteroaryl group ５ and / or L ６ (That is, L ５ , L ６ , or L ５ and L ６ Each of these groups is preferably a combination of one or two arylene groups selected from the group consisting of single-bonded, substituted, or unsubstituted phenylene groups and naphthylene groups, and more preferably a single-bonded, substituted, or unsubstituted phenylene group.

[0076] In general formula (III), Ar ６ ~Ar ８ L bonded to the condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8) above ４ ~L ６ It is preferable that the group is a single bond or a substituted or unsubstituted arylene group. That is, for example, Ar ６If is a condensed polycyclic aromatic group represented by the general formulas (IV-1) to (IV-8), then L ４ It is preferable that the phenylene group is a single bond, substituted, or unsubstituted. The L bonded to the condensed polycyclic aromatic group ４ ~L ６ In the "substituted or unsubstituted arylene group" as such, the "arylene group" is preferably one, two, or three combinations independently selected from the group consisting of substituted or unsubstituted phenylene groups, biphenylylene groups, and naphthylene groups, more preferably one or two combinations selected from the group consisting of substituted or unsubstituted phenylene groups and biphenylylene groups, and even more preferably an unsubstituted phenylene group or an unsubstituted biphenylylene group.

[0077] L bonded to the condensed polycyclic aromatic group ４ ~L ６ In the above, the "phenylene group" in the "substituted or unsubstituted phenylene group" as a substituted or unsubstituted arylene group is preferably a 1,3-phenylene group or a 1,4-phenylene group, and more preferably a 1,4-phenylene group. The "biphenylene group" in the "substituted or unsubstituted biphenylylene group" is preferably a 1,1'-biphenyl-4,3'-diyl group or a 1,1'-biphenyl-4,4'-diyl group, and more preferably a 1,1'-biphenyl-4,4'-diyl group. The "naphthylene group" in the "substituted or unsubstituted naphthylene group" is preferably a 2,6-naphthylene group.

[0078] In general formulas (IV-1) to (IV-8), X and Y are each independently -CR ５ R ６ -, -NR ７ Represents -, -O-, or -S-. In general formulas (IV-1) to (IV-4), X is -CR ５ R ６ - or -O- is preferred, and -CR ５ R ６ - is more preferable. In general formulas (IV-1) to (IV-4), X is -CR ５R ６ If -, then general formulas (IV-1) to (IV-4) represent an indenophenanthryl group. Of the indenophenanthryl groups represented by general formulas (IV-1) to (IV-4), the indenophenanthryl groups represented by general formulas (IV-1) to (IV-3) are preferred, and the indenophenanthryl group represented by general formula (IV-3) is more preferred.

[0079] In general formulas (IV-5) to (IV-8), at least one of X and Y is -CR ５ R ６ It represents - or -O-. X is -CR ５ R ６ - or -O- is preferred, and -CR ５ R ６ - is more preferable. Y is -CR ５ R ６ It is preferable that it be -, -O-, or -S-, and more preferably -O- or -S-. In general formulas (IV-5) to (IV-8), the combination of X and Y is -CR ５ R ６ - and Y is preferably -O- or -S-, and X is -CR ５ R ６ - and it is more preferable that Y is -O-. X is -CR ５ R ６ When Y is -O-, the general formulas (IV-5) to (IV-8) represent an indenodibenzofuranyl group, and X is -CR ５ R ６ When Y is -S-, general formulas (IV-5) to (IV-8) represent an indenodibenzothienyl group. In general formula (III), the indenodibenzofuranyl group or indenodibenzothienyl group represented by general formulas (IV-5) to (IV-8) is preferably an indenodibenzofuranyl group or indenodibenzothienyl group represented by general formula (IV-5) or (IV-6).

[0080] In general formulas (IV-1) to (IV-8), R ２ ~R ４Preferably, the group is a deuterium atom, a cyano group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aryloxy group; more preferably, it is a deuterium atom, a cyano group, a substituted or unsubstituted linear alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted phenyloxy group; and even more preferably, it is a substituted or unsubstituted vinyl group, an unsubstituted phenyl group, an unsubstituted phenanthryl group, or an unsubstituted phenyloxy group.

[0081] In general formulas (IV-1) to (IV-8), R ５ ~R ７ It is preferably a hydrogen atom, a deuterium atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aryloxy group; more preferably a hydrogen atom, a substituted or unsubstituted linear alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted phenyloxy group; and even more preferably a hydrogen atom, a methyl group, or an unsubstituted phenyl group. ５ and R ６ If the compound is a phenyl group, these phenyl groups may be bonded to each other by single bonds to form a ring.

[0082] In general formulas (IV-1) to (IV-8), p is R ２ This is the number of elements, and represents an integer from 0 to 7. q is R ３ This is the number of elements, and represents an integer from 0 to 4. r is R ４ This is the number of elements, representing an integer from 0 to 5. There are multiple instances of R if p, q, and r are each independently 2 or greater. ２ ~R ４ These may be the same or different from each other, and may be multiple adjacent Rs. ２ ~R４ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms, forming a ring. Also, * represents L in general formula (III). ４ ~L ６ This represents the connection between the two. p, q, and r are each independently preferably integers between 0 and 2, more preferably 0 or 1, and particularly preferably 0.

[0083] In general formulas (III) and (IV-1) to (IV-8), L ４ ~L ６ Ar ６ ~Ar ８ , or R ２ ~R ７ If each of the above groups represented by has one or more substituents, the substituents are preferably a deuterium atom, a cyano group, a fluorine atom, a silyl group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted aryloxy group, or a substituted or unsubstituted heteroaryl group. More preferably, the substituents are selected from the group consisting of a deuterium atom, a substituted or unsubstituted linear alkyl group having 1 to 4 carbon atoms, and substituted or unsubstituted phenyl group, biphenylyl group, phenyloxy group, and carbazolyl group. Even more preferably, the substituents are selected from the group consisting of a deuterium atom, a cyano group, and unsubstituted methyl group, tert-butyl group, phenyl group, biphenylyl group, and phenyloxy group.

[0084] Specific examples of compounds represented by general formula (III) are given below. However, the compounds represented by general formula (III) that can be used in the present invention should not be interpreted as being limited by the following specific examples. Also, in the chemical structural formulas below, hydrogen atoms ( １ The notation H) is omitted, and the deuterium atom ( ２ H) is written as "D".

[0085]

[0086] The compound represented by general formula (III) may be selected from the group consisting of chemical formulas 1 to 165 described in Korean Published Patent No. 10-2017-0056422. Alternatively, the compound represented by general formula (III) may be selected from the group consisting of compounds 52 to 86 described in Korean Published Patent No. 10-2018-0027195. The contents of the above-mentioned Korean patent publications cited in this paragraph are incorporated herein by reference as part of this specification. Furthermore, the compound represented by general formula (III) can be synthesized by referring to the synthesis procedure described in the above-mentioned publications.

[0087] <Organic Electroluminescent Element> The organic EL element of the present invention comprises at least an anode and a cathode, and a hole transport layer, an electron blocking layer, an emissive layer, and an electron transport layer sandwiched between the anode and the cathode. In the organic EL element of the present invention, the electron blocking layer contains a compound represented by general formula (I), and the emissive layer contains a compound represented by general formula (III).

[0088] [Electrodes and Organic Layers Constituting the Element] As an example of the structure of an organic EL element, as shown in Figure 1, an anode 2, a hole transport layer 4, electron blocking layers (5, 6), an emissive layer 7, an electron transport layer 8, a cathode 10, and a capping layer 11 are sequentially stacked on a glass substrate 1. Other examples include having a hole injection layer 3 between the anode 2 and the hole transport layer 4, having a hole blocking layer (not shown) between the emissive layer 7 and the electron transport layer 8, and having an electron injection layer 9 between the electron transport layer 8 and the cathode 10. In other words, as long as the organic EL element of the present invention has at least an anode, a hole transport layer, an electron blocking layer, an emissive layer, an electron transport layer, and a cathode in this order, it does not exclude configurations in which other layers are present between each layer. In such a multilayer structure, one organic layer can serve multiple roles. For example, a configuration in which a hole injection layer and a hole transport layer are combined, and / or a configuration in which an electron transport layer and an electron injection layer are combined, is also possible. Furthermore, a configuration in which two or more organic layers having the same function are stacked is also possible. Specifically, examples include a configuration with two stacked hole transport layers, a configuration with two stacked electron blocking layers, a configuration with two stacked light-emitting layers, a configuration with two stacked electron transport layers, and / or a configuration with two stacked capping layers. For example, the electron blocking layer can have a stacked structure of two or more layers, including a first electron blocking layer 5 in contact with the hole transport layer and a second electron blocking layer 6 in contact with the light-emitting layer. In the organic EL element of the present invention, if there is a configuration in which multiple electron blocking layers and / or light-emitting layers are stacked, it is sufficient that at least one layer of the electron blocking layer contains a compound represented by general formula (I), and at least one layer of the light-emitting layer contains a compound represented by general formula (III).

[0089] In one aspect of the present invention, each organic layer constituting the organic EL element may be formed as a single film made of one type of material, or as a mixed film made by mixing multiple materials. Furthermore, it may be a single-layer structure of a single film or a mixed film, a laminated structure in which multiple single films are stacked, a laminated structure in which multiple mixed films are stacked, or a laminated structure in which one or more single films and one or more mixed films are stacked. Film formation can be carried out by known methods such as vapor deposition, spin coating, and inkjet. The individual components and layers of the organic EL element will be described in detail below.

[0090] [Anode] For the anode, electrode materials with a large work function, such as ITO (indium tin oxide) or gold, are used.

[0091] [Hole Injection Layer, Hole Transport Layer] The hole injection layer is provided between the anode and the light-emitting layer, or between the anode and the hole transport layer, and has the function of lowering the driving voltage and improving the luminescence brightness by lowering the injection barrier of holes supplied from the anode. The hole transport layer is a layer that has the function of transporting holes. The hole transport layer may also be a hole injection transport layer that also functions as a hole injection layer. Compounds represented by general formula (I) can be used as materials for the hole injection layer, hole transport layer, and hole injection transport layer. The compound represented by general formula (I) used in these layers may be one or more types from the group of compounds represented by general formula (I). In addition, a compound represented by general formula (I) may be used in combination with other hole injection materials and hole transport materials. Materials that can be used other than the compound represented by general formula (I) are described below.

[0092] As materials for the hole injection layer, porphyrin compounds such as copper phthalocyanine, starburst-type triphenylamine derivatives, arylamine compounds having two or more triphenylamine or carbazolyl structures in the molecule, each linked by a single bond or a divalent group that does not contain heteroatoms, acceptor-type heterocyclic compounds such as hexacyanoazatriphenylene, and coated polymer materials can be used.

[0093] As hole-injection layers, hole transport layers, and hole-transporting materials that can be used in the hole-injection transport layers, benzidine derivatives such as N,N'-diphenyl-N,N'-di(m-tolyl)-benzidine (TPD), N,N'-diphenyl-N,N'-di(α-naphthyl)-benzidine (NPD), and N,N,N',N'-tetrabiphenylbenzidine, 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC), and arylamine compounds having two or more triphenylamine or carbazolyl structures in the molecule, each linked by a single bond or a divalent group that does not contain heteroatoms can be used. In addition, as materials for the hole-injection layers, hole transport layers, and hole-injection transport layers, coating-type polymer materials such as poly(3,4-ethylenedioxythiophene) (PEDOT) / poly(styrene sulfonate) (PSS) can be used.

[0094] Furthermore, hole injection layers, hole transport layers, and hole injection transport layers may be constructed by adding P-type dopants such as trisbromophenylamine hexachloroantimony or radialene derivatives described in European Patent No. 2684932 to these hole injection materials and hole transport materials, or by adding polymer compounds having the structure of benzidine derivatives such as TPD as a substructure.

[0095] In the present invention, the absolute value of the HOMO energy level of the hole transport material is preferably greater than the absolute value of the HOMO energy level of general hole transport materials such as NPDs and TPDs (5.4 eV) (i.e., it has a deeper HOMO energy level), and preferably smaller than the absolute value of the HOMO energy level of the electron blocking material described later. Specifically, the absolute value of the HOMO energy level of the hole transport material is preferably 5.45 eV or more and 5.80 eV or less, and more preferably 5.60 eV or more and 5.75 eV or less.

[0096] [Electron Blocking Layer] An electron blocking layer is placed, for example, between an emissive layer and a hole transport layer, and has the function of suppressing the diffusion of electrons present in the emissive layer to the outside (hole transport layer side). This can improve the probability of electron-hole recombination in the emissive layer. An electron blocking layer usually also has the function of transporting holes. Furthermore, an electron blocking layer may also function as an exciton blocking layer, suppressing the diffusion of excitons from the emissive layer.

[0097] In the present invention, the electron blocking layer contains a compound represented by general formula (I). The compound represented by general formula (I) may be contained in organic layers other than the electron blocking layer, but is contained in at least the electron blocking layer. When the electron blocking layer has a two-layer stacked configuration, the compound represented by general formula (I) may be contained in either the first electron blocking layer or the second electron blocking layer, or in both the first and second electron blocking layers, but is preferably contained in the second electron blocking layer. The compound represented by general formula (I) may be contained only in the electron blocking layer among the organic layers provided between the anode and the light-emitting layer, or it may be further contained in, for example, the hole transport layer.

[0098] Compounds represented by general formula (I) exhibit excellent hole injection, hole transport, and electron blocking properties, high electron resistance, and stability even in thin film states, enabling the confinement of excitons generated within the light-emitting layer. Therefore, organic EL devices using compounds represented by general formula (I) as electron blocking materials have a higher probability of hole-electron recombination and suppressed thermal deactivation, resulting in high luminous efficiency. Furthermore, the driving voltage is reduced, improving current resistance, and thus increasing maximum luminous brightness and device lifetime. The compound represented by general formula (I) used in the electron blocking layer may be one type from the group of compounds represented by general formula (I), or two or more types. In addition, compounds represented by general formula (I) may be used in combination with other electron blocking materials. The following describes materials that can be used other than compounds represented by general formula (I).

[0099] Other than arylamine compounds represented by general formula (I), electron-blocking compounds can be used as materials for the electron-blocking layer, such as carbazole derivatives like 4,4',4''-tri(N-carbazolyl)triphenylamine (TCTA), 9,9-bis[4-(carbazole-9-yl)phenyl]fluorene, 1,3-bis(carbazole-9-yl)benzene (mCP), and 2,2-bis(4-carbazole-9-ylphenyl)adamantane (Ad-Cz), and compounds having electron-blocking properties such as compounds having a triphenylsilyl group and a triarylamine structure, represented by 9-[4-(carbazole-9-yl)phenyl]-9-[4-(triphenylsilyl)phenyl]-9H-fluorene.

[0100] The glass transition temperature of the electron-blocking material is preferably 100.0°C or higher, more preferably 105.0°C or higher, and even more preferably 110.0°C or higher. Furthermore, the absolute value of the HOMO energy level of the electron-blocking material is preferably greater than the absolute value of the HOMO energy level of the hole-transporting material (i.e., it has a deeper HOMO level). Specifically, the absolute value of the HOMO energy level of the electron-blocking material is preferably 5.55 eV or more and 5.90 eV or less, and more preferably 5.65 eV or more and 5.80 eV. Furthermore, the absolute value of the HOMO energy level of the electron blocking material is preferably 0.05 eV to 0.45 eV greater than the absolute value of the HOMO energy level of the hole transport material, more preferably 0.05 eV to 0.35 eV greater, and even more preferably 0.10 eV to 0.35 eV greater.

[0101] [Emitting Layer] The emissive layer is a layer that emits light after generating excitons through the recombination of holes and electrons injected from the anode and cathode, respectively. An emissive material may be used alone as the emissive layer, but preferably the emissive layer includes an emissive material and a host material.

[0102] In the organic EL element of the present invention, the light-emitting layer contains a compound represented by the general formula (III). The compound represented by the general formula (III) may be contained only in the light-emitting layer of the organic EL element, or it may also be contained in organic layers other than the light-emitting layer (for example, a hole transport layer).

[0103] The compound represented by general formula (I) can exhibit even better effects when used in combination with the compound represented by general formula (III) in an organic EL element. That is, by using both compounds in combination in an organic EL element, the luminous efficiency is further improved, and the durability of the element can be further enhanced by lowering the driving voltage, making it easier to obtain characteristics of higher efficiency, lower driving voltage, and longer lifespan. In other words, according to the present invention, it is possible to provide an organic EL element having an electron blocking layer containing the compound represented by general formula (I) and an emissive layer containing the compound represented by general formula (III) (it is preferable that these two layers are adjacent to each other), which are used in combination with the compound represented by general formula (III).

[0104] In addition to compounds represented by general formula (III), known luminescent materials and host materials can be used for the luminescent layer. The luminescent material may be a fluorescent material, a phosphorescent material, or a delayed-fluorescence material, but a phosphorescent material is preferred. The host material preferably contains a compound represented by general formula (III).

[0105] As a fluorescent material, tris(8-quinolinolato)aluminum (Alq ３ In addition to metal complexes of quinolinol derivatives, including ), various metal complexes, anthracene derivatives, bis-styrylbenzene derivatives, pyrene derivatives, oxazole derivatives, and poly(p-phenylenevinylene) derivatives can be used. Furthermore, quinacridone, coumarin, rubrene, perylene, and their derivatives, benzopyran derivatives, indenophenanthrene derivatives, rhodamine derivatives, aminostyryl derivatives, and the like can be used.

[0106] As phosphorescent materials, metal complexes with iridium or platinum as the central metal can be used. For example, Ir(ppy)３ Green phosphorescent materials such as FIRPIC and FIr6, blue phosphorescent materials such as FIRPIC and FIr6, and red phosphorescent materials such as Btp2Ir(acac) are used. To avoid concentration quenching, the amount of phosphorescent material doped into the host material is preferably in the range of 1 to 30% by mass relative to the total amount of the light-emitting layer, and is preferably doped by co-deposition.

[0107] Examples of delayed fluorescence materials include carbazolyl dicyanobenzene (CDCB) derivatives such as PIC-TRZ, CC2TA, PXZ-TRZ, and 4CzIPN. Specific examples of these and other delayed fluorescence materials can be found in Non-Patent Document 1.

[0108] Examples of host materials used in the light-emitting layer include anthracene derivatives, heterocyclic compounds having an indole ring as a substructure of the fused ring, heterocyclic compounds having a carbazole ring as a substructure of the fused ring, carbazole derivatives, thiazole derivatives, benzimidazole derivatives, and polydialkylfluorene derivatives. Examples of host materials having hole injection and hole transport properties include carbazole derivatives such as 4,4'-di(N-carbazolyl)biphenyl (CBP), TCTA, and mCP, while examples of host materials having electron transport properties include p-bis(triphenylsilyl)benzene (UGH2) and 2,2',2''-(1,3,5-phenylene)-tris(1-phenyl-1H-benzimidazole) (TPBI).

[0109] [Hole Blocking Layer] The hole blocking layer is placed, for example, between the light-emitting layer and the electron transport layer, and has the function of suppressing the diffusion of holes present in the light-emitting layer to the outside of the light-emitting layer (towards the electron transport layer). This can improve the probability of electron-hole recombination in the light-emitting layer. The hole blocking layer usually also has the function of transporting electrons. Furthermore, the hole blocking layer may also function as an exciton blocking layer, suppressing the diffusion of excitons from the light-emitting layer. As materials for the hole blocking layer, metal complexes of phenanthroline derivatives such as bathocuproine (BCP) and quinolinol derivatives such as bis(2-methyl-8-quinolinate)-4-(phenylphenolate)aluminum (BAlq), as well as various rare earth complexes, triazole derivatives, triazine derivatives, and oxadiazole derivatives, etc., which have hole-blocking properties can be used. These materials may also serve as materials for the electron transport layer.

[0110] [Electron injection layer, electron transport layer] The electron injection layer is provided between the cathode and the light-emitting layer, or between the cathode and the electron transport layer, and has the function of lowering the driving voltage and improving the luminescence brightness by lowering the injection barrier of electrons supplied from the cathode. The electron transport layer is a layer that has the function of transporting electrons. The electron transport layer may also be an electron injection transport layer that also functions as an electron injection layer.

[0111] As for the electron transport layer material, Alq ３ In addition, metal complexes of quinolinol derivatives including BAlq, various metal complexes, triazole derivatives, triazine derivatives, oxadiazole derivatives, pyridine derivatives, pyrimidine derivatives, benzimidazole derivatives, thiadiazole derivatives, anthracene derivatives, carbodiimide derivatives, quinoxaline derivatives, pyridoindole derivatives, phenanthroline derivatives, and silole derivatives can be used.

[0112] As materials for the electron injection layer, alkali metal salts such as lithium fluoride and cesium fluoride, alkaline earth metal salts such as magnesium fluoride, metal complexes of quinolinol derivatives such as lithium quinolinol, metal oxides such as aluminum oxide, or metals such as ytterbium (Yb), samarium (Sm), calcium (Ca), strontium (Sr), and cesium (Cs) can be used. By constructing the electron transport layer and cathode from preferred materials, the electron injection layer can be omitted.

[0113] In the electron injection layer or electron transport layer, metals such as cesium (N-type dopants) may be added to the electron injection material or electron transport material.

[0114] [Cathode] For the cathode, metals with a low work function such as aluminum, or alloys with an even lower work function such as magnesium-silver alloy, magnesium-indium alloy, or aluminum-magnesium alloy can be used.

[0115] When a DC voltage is applied to the organic EL element according to the present invention in air at 25°C, the maximum wavelength of the emission spectrum is preferably 600 nm or more and 700 nm or less.

[0116] <Electronic Elements or Electronic Devices> The electronic elements or electronic devices of the present invention have a pair of electrodes and at least two organic layers sandwiched between the pair of electrodes, wherein at least one of the organic layers contains an arylamine compound represented by general formula (I), and another organic layer adjacent to the organic layer containing the arylamine compound represented by general formula (I) contains an arylamine compound represented by general formula (III). Preferably, the organic layers have at least a hole transport layer, an electron blocking layer, an emitting layer, and an electron transport layer, more preferably the electron blocking layer contains a compound represented by general formula (I) and the emitting layer contains a compound represented by general formula (III). Examples of electronic devices include display devices and light-emitting devices equipped with organic EL elements, electrophotographic photoreceptors, image sensors, photoelectric conversion elements, and solar cells. Examples of display devices include display components such as organic EL panel modules, televisions, mobile phones, tablets, and personal computers. Examples of light-emitting devices include lighting and vehicle lights.

[0117] The embodiments of the present invention will be specifically described below with reference to examples. The materials, processing content, and processing procedures shown below can be modified as appropriate, as long as they do not exceed the spirit of the present invention. In other words, the scope of the present invention is not limited to the following examples. The reagents used in the synthesis examples are manufactured by Tokyo Chemical Industry Co., Ltd., Sigma-Aldrich, or Alfa Aesar, etc. Furthermore, all reactions in the synthesis examples were carried out using a reaction vessel equipped with a condenser, a stirrer, and a thermometer. The identification of the synthesized compounds was as follows: １ Analysis was performed using 1H-NMR (Bruker Ascend™, 400 MHz) or MS (AVICY-EXCOREA API3200 mass spectrometer).

[0118] [Synthesis Examples] <Synthesis Example 1: Synthesis of Compound (1-4)> In a reaction vessel, 10.0 g of bis(4-naphthalene-2-yl-phenyl)amine, 11.0 g of 4-bromo-2',5'-diphenyl-biphenyl, 0.1 g of palladium(II) acetate, 0.2 g of tri(t-butyl)phosphine, and 2.7 g of t-butoxysodium were charged and stirred under reflux in toluene for 3 hours. After cooling, the filtrate obtained by filtration was concentrated to obtain the crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 9.0 g of white powder of bis(4-naphthalene-2-yl-phenyl)-(2',5'-diphenyl-biphenyl-4-yl)amine (compound (1-4)): (yield: 52.3%).

[0119] Regarding the obtained white powder, １ H-NMR (CDCl ３ The following 39 hydrogen signals were detected and their structures identified: δ (ppm) = 8.06 (2H), 7.92 (6H), 7.78 (4H), 7.73 (1H), 7.68 (5H), 7.53 (7H), 7.42 (1H), 7.39-7.23 (9H), 7.14 (4H).

[0120] <Synthesis Example 2: Synthesis of Compound (1-58)> In a reaction vessel, 8.5 g of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-1-ylphenyl)-amine, 4.8 g of 9-bromophenancelene, 0.1 g of palladium(II) acetate, 0.3 g of tri(t-butyl)phosphine, and 2.3 g of t-butoxysodium were charged and stirred under reflux in toluene for 3 hours. After cooling, the filtrate obtained by filtration was concentrated to obtain the crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 8.3 g of white powder (yield: 73.1%) of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-1-ylphenyl)-phenancelene-9-ylamine (compound (1-58)).

[0121] Regarding the obtained white powder, １ H-NMR (CDCl ３The following 37 hydrogen signals were detected and their structures identified: δ (ppm) = 8.79 (1H), 8.75 (1H), 8.14 (1H), 8.03 (1H), 7.92 (1H), 7.85 (2H), 7.72 (6H), 7.65 (2H), 7.60 (1H), 7.50 (7H), 7.42 (1H), 7.36 (3H), 7.27-7.18 (6H), 7.09 (4H).

[0122] <Synthesis Example 3: Synthesis of Compound (1-59)> In a reaction vessel, 8.0 g of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-ylphenyl)-amine, 4.5 g of 9-bromophenancelene, 0.1 g of palladium(II) acetate, 0.2 g of tri(t-butyl)phosphine, and 2.2 g of t-butoxysodium were charged and stirred under reflux in toluene for 3 hours. After cooling, the filtrate obtained by filtration was concentrated to obtain the crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 6.6 g of pale yellow powder of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-ylphenyl)-phenancelene-9-ylamine (compound (1-59)): (yield: 61.7%).

[0123] Regarding the pale yellow powder obtained, １ H-NMR (CDCl ３ The following 37 hydrogen signals were detected and their structures identified: δ (ppm) = 8.79 (1H), 8.74 (1H), 8.09 (1H), 8.01 (1H), 7.86 (4H), 7.75 (1H), 7.71 (5H), 7.66 (2H), 7.60 (3H), 7.50 (5H), 7.39 (1H), 7.34-7.23 (6H), 7.20 (2H), 7.07 (4H).

[0124] <Synthesis Example 4: Synthesis of Compound (1-69)> In a reaction vessel, 6.0 g of (4-naphthalene-2-yl-phenyl)phenylamine, 10.3 g of 4-bromo-2'',5''-diphenyl-[1,1';4',1'']terphenyl, 0.1 g of palladium(II) acetate, 0.2 g of tri(t-butyl)phosphine, and 2.3 g of t-butoxysodium were charged and stirred under reflux overnight in toluene solvent. After cooling, the filtrate obtained by filtration was concentrated to obtain the crude product. The crude product obtained was purified by column chromatography (support: silica gel, eluent: dichloromethane / n-heptane) to obtain 7.1 g (yield: 51.7%) of a white powder of (2'',5'',-diphenyl-[1,1';4',1'']terphenyl-4-yl)-(4-naphthalene-2-ylphenyl)-phenylamine (compound (1-69)).

[0125] Regarding the obtained white powder, １ H-NMR (CDCl ３ The following 37 hydrogen signals were detected and their structures identified: δ (ppm) = 8.04 (1H), 7.91 (3H), 7.73 (5H), 7.66 (2H), 7.56 (2H), 7.51 (7H), 7.42 (1H), 7.39-7.18 (15H), 7.10 (1H).

[0126] <Synthesis Example 5: Synthesis of Compound (1-83)> In a reaction vessel, 11.0 g of (4-phenanthrene-9-yl-phenyl)phenylamine, 16.2 g of 4-bromo-2'',5''-[1,1';4',1'']terphenyl, 0.1 g of palladium(II) acetate, 0.3 g of tri(t-butyl)phosphine, and 3.7 g of t-butoxysodium were charged and stirred under reflux overnight in toluene solvent. After cooling, the filtrate obtained by filtration was concentrated to obtain the crude product. The crude product obtained was purified by column chromatography (support: silica gel, eluent: dichloromethane / n-heptane) to obtain 11.2 g (yield: 48.5%) of a white powder of (2'', 5'', diphenyl-[1,1'; 4',1'']terphenyl-4-yl)-(4-phenanthrene-9-ylphenyl)-phenylamine (compound (1-83)).

[0127] Regarding the obtained white powder, １ H-NMR (CDCl ３ The following 39 hydrogen signals were detected and their structures identified: δ (ppm) = 8.81 (1H), 8.75 (1H), 8.09 (1H), 7.93 (1H), 7.71 (7H), 7.65–7.44 (10H), 7.44–7.22 (17H), 7.11 (1H).

[0128] <Synthesis Example 6: Synthesis of Compound (1-96)> In a reaction vessel, 50.0 g of 4-bromoaniline, 113.9 g of 4,4,5,5-tetramethyl-2-[1,1':4',1''-terphenyl]-2'-yl-1,3,2-dioxaborolane, 350 mL of toluene, 88 mL of ethanol, 80.4 g of potassium carbonate, and 290 mL of water were charged. 6.7 g of tetrakistriphenylphosphine palladium was added, and the mixture was stirred under reflux for 14 hours. After cooling, the organic layer obtained by liquid-liquid extraction was sequentially washed with water and saturated brine, and dried over anhydrous magnesium sulfate. After removing the drying agent by filtration, the filtrate was concentrated. 450 mL of heptane was added to the residue and stirred overnight at room temperature. The solid was then collected by filtration to obtain 77.8 g of a yellowish-white powder of [1,1':2',1'':4'',1''''-quarterphenyl]-4-amine (yield: 83.3%).

[0129] In a reaction vessel, 55.0 g of [1,1':2',1'':4'',1'''-quarterphenyl]-4-amine, 74.9 g of 2-(4-bromophenyl)naphthalene, 28.0 g of t-butoxysodium, 420 mL of toluene, 0.9 g of tris(dibenzylideneacetone)dipalladium, and 2.4 g of 2,2'-bis(diphenylphosphin)-1,1'-binaphthyl were charged and stirred under reflux for 15 hours. After cooling to 80°C, the solid was removed by thermal filtration using a funnel lined with Celite. The filtrate was heated and stirred, 50 g of silica gel was added at 80°C and stirred for 1 hour, after which the solid was removed by thermal filtration. The filtrate was concentrated, and the resulting residue was recrystallized using a toluene / acetone mixed solvent to obtain 69.5 g (yield: 68.3%) of N-(4-(2-naphthyl)phenyl)-[1,1':2',1'':4'',1''''-quarterphenyl]-4-amine as a yellowish-white powder.

[0130] In a reaction vessel, 69.5 g of N-(4-(2-naphthyl)phenyl)-[1,1':2',1'':4'',1''''-quarterphenyl]-4-amine, 45.1 g of 1-bromo-4-iodobenzene, 25.7 g of t-butoxysodium, 700 mL of toluene, 2.5 g of copper iodide, and 2.3 g of N,N'-dimethylethylenediamine were charged and stirred under reflux for 16 hours. After cooling to 80°C, the solid was removed by thermal filtration using a funnel lined with Celite. The filtrate was concentrated, and the resulting residue was purified by column chromatography (support: silica gel, eluent: dichloromethane / n-heptane) to obtain 59.4 g (yield: 65.5%) of a yellowish-white powder of N-(4-bromophenyl)-N-(4-(2-naphthyl)phenyl)-[1,1':2',1'':4'',1'''-quarterphenyl]-4-amine.

[0131] In a reaction vessel, 12.0 g of N-(4-bromophenyl)-N-(4-(2-naphthyl)phenyl)-[1,1':2',1'':4'',1''''-quarterphenyl]-4-amine, 5.3 g of 3-(2-naphthyl)phenylboronic acid, 84 mL of toluene, 21 mL of ethanol, 4.9 g of potassium carbonate, and 18 mL of water were charged. 0.4 g of tetrakistriphenylphosphine palladium was added, and the mixture was stirred under reflux for 14 hours. After cooling, 84 mL of methanol was added, and the precipitated solid was collected by filtration. To the obtained solid, 70 mL of water and 70 mL of methanol were added, and the mixture was dispersed and washed under reflux for 1 hour. The solid was collected by filtration, 140 mL of toluene was added, and the mixture was heated to 100°C to remove water and methanol. After cooling to 80°C, 7 g of silica gel and 7 g of activated clay were added, and the mixture was stirred for 1 hour. The solid was removed by filtration, and the filtrate was concentrated. 140 mL of acetone was added to the residue and stirred overnight at room temperature, after which the solid was collected by filtration. The obtained solid was recrystallized using a toluene / acetone mixed solvent to obtain 11.3 g (yield: 79.6%) of N-(3'-(naphthalene-2-yl)-[1,1'-biphenyl]-4-yl)-N-(4-(naphthalene)-2-yl)phenyl)-5'-phenyl-[1,1':2',1''-terphenyl]-4-amine (compound (1-96)) as a yellowish-white powder.

[0132] Regarding the yellowish-white powder obtained, １ H-NMR (CDCl ３ The following 43 hydrogen signals were detected and their structures identified: δ (ppm) = 8.09 (1H), 8.01 (1H), 7.77–7.92 (8H), 7.43–7.73 (19H), 7.21–7.38 (10H), 7.04–7.13 (4H).

[0133] <Synthesis Example 7: Synthesis of Compound (1-97)> In a reaction vessel, 20.0 g of 2'-chloro-[1,1':4',1''-terphenyl], 29.5 g of N-phenyl-4'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1'-biphenyl]-4-amine, 200 mL of 1,4-dioxane, 32.1 g of potassium phosphate, and 60 mL of water were charged. 2.1 g of tris(dibenzylideneacetone)dipalladium and 2.1 g of tricyclohexylphosphine were added, and the mixture was stirred under reflux for 14 hours. After cooling, 200 mL of methanol was added, and the precipitated solid was collected by filtration. Chlorobenzene was added to the obtained solid, and the mixture was heated to 100°C, then cooled to 80°C. 9 g of silica gel and 9 g of activated clay were added, and the mixture was stirred for 1 hour. The solid was removed by filtration, and the filtrate was concentrated. 360 mL of acetone was added to the residue and stirred overnight at room temperature. The solid was then collected by filtration to obtain 30.6 g of a yellowish-white powder of N,4'-diphenyl-[1,1':2',1'':4'',1''''-terphenyl]-4''''-amine (yield: 85.5%).

[0134] In a reaction vessel, 20.0 g of N,4'-diphenyl-[1,1':2',1'':4'',1'''-terphenyl]-4''''-amine, 18.5 g of 2-bromo-9,9-diphenyl-9H-fluorene, 200 mL of toluene, and 6.1 g of t-butoxysodium were charged. 0.1 g of tris(dibenzylideneacetone)dipalladium and 0.2 g of a 50% toluene solution of tri(t-butyl)phosphine were added, and the mixture was stirred under reflux for 14 hours. After cooling to 80°C, the mixture was thermally filtered using a funnel lined with Celite to remove the solid. The filtrate was heated and stirred, and at 80°C, 12 g of silica gel and 12 g of activated clay were added and the mixture was stirred for 1 hour. The solid was removed by filtration, and the filtrate was concentrated. The obtained residue was recrystallized using a toluene / acetone mixed solvent to obtain 21.4 g (yield: 64.1%) of a yellowish-white powder of N,9,9-triphenyl-N-(4'-phenyl-[1,1':2',1'':4'',1''''-quarterphenyl]-4'''-yl)-9H-fluoren-2-amine (compound (1-97)).

[0135] Regarding the yellowish-white powder obtained, １ H-NMR (CDCl ３ The following 43 hydrogen signals were detected and their structures identified: δ (ppm) = 7.64–7.71 (5H), 7.58–7.60 (1H), 7.51–7.53 (1H), 7.41–7.48 (6H), 7.30–7.38 (3H), 7.14–7.24 (21H), 6.98–7.09 (6H).

[0136] <Synthesis Example 8: Synthesis of Compound (1-102)> In a reaction vessel, 31.0 g of 4-bromo-2-chloro-1,1'-biphenyl, 22.0 g of 2-naphthaleneboronic acid, 240 mL of toluene, 60 mL of ethanol, 24.1 g of potassium carbonate, and 80 mL of water were charged. 1.3 g of tetrakistriphenylphosphine palladium was added and the mixture was stirred under reflux for 15 hours. After cooling, the organic layer obtained by liquid-liquid extraction was washed with water. The organic layer was stirred, heated to 100°C to confirm that it was free of water, then cooled to 80°C, and 20 g of silica gel was added and the mixture was stirred for 1 hour. The solid was removed by thermal filtration, and the filtrate was concentrated. The resulting residue was recrystallized using a toluene / heptane mixed solvent to obtain 25.6 g of gray powder of 2-(2-chloro-[1,1'-biphenyl]-4-yl)naphthalene (yield: 63.5%).

[0137] In a reaction vessel, 20.0 g of 2-(2-chloro-[1,1'-biphenyl]-4-yl)naphthalene, 24.8 g of N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-[1,1'-biphenyl]-4-amine, 160 mL of 1,4-dioxane, 27.0 g of potassium phosphate, and 60 mL of water were charged. 1.8 g of tris(dibenzylideneacetone)dipalladium and 1.8 g of tricyclohexylphosphine were added, and the mixture was stirred under reflux for 12 hours. After cooling, the organic solvent was removed by distillation under reduced pressure, and the residue was extracted with toluene. The resulting organic layer was sequentially washed with water and saturated brine, and then dried over anhydrous magnesium sulfate. The drying agent was removed by filtration, and the filtrate was stirred and heated. 20 g of silica gel was added at 80°C. After stirring for one hour, the solid was removed by thermal filtration, and the filtrate was concentrated. The resulting residue was recrystallized using toluene solvent to obtain 26.0 g of a yellowish-white powder of N-([1,1'-biphenyl]-4-yl)-5'-(naphthalene-2-yl)-[1,1':2',1''-terphenyl]-4-amine (yield: 78.0%).

[0138] In a reaction vessel, 24.6 g of N-([1,1'-biphenyl]-4-yl)-5'-(naphthalene-2-yl)-[1,1':2',1''-terphenyl]-4-amine, 14.7 g of 2-(4-bromophenyl)naphthalene, 250 mL of toluene, and 6.8 g of t-butoxysodium were charged. 0.4 g of tris(dibenzylideneacetone)dipalladium and 0.4 g of a 50% toluene solution of tri(t-butyl)phosphine were added, and the mixture was stirred under reflux for 4 hours. After cooling to 80°C, the mixture was thermally filtered using a funnel lined with Celite to remove the solid. The filtrate was heated and stirred, and at 80°C, 17 g of silica gel and 17 g of activated clay were added and the mixture was stirred for 1 hour. The solid was removed by filtration, and the filtrate was concentrated. The resulting residue was subjected to crystallization purification using a toluene / acetone mixed solvent to obtain 21.0 g (yield: 61.5%) of a yellowish-white powder of N-([1,1'-biphenyl]-4-yl)-5'-(naphthalene-2-yl)-N-(4-(naphthalene-2-yl)phenyl)-[1,1':2',1''-terphenyl]-4-amine (compound (1-102)).

[0139] Regarding the yellowish-white powder obtained, １ H-NMR (CDCl ３ The following 39 hydrogen signals were detected and their structures identified: δ (ppm) = 8.14 (1H), 8.01 (1H), 7.82–7.93 (8H), 7.71–7.77 (2H), 7.39–7.63 (13H), 7.05–7.32 (14H).

[0140] <Synthesis Example 9: Synthesis of Compound (1-103)> In a reaction vessel, 32.7 g of 2'-bromo-[1,1':4',1''-terphenyl], 24.8 g of N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-[1,1'-biphenyl]-4-amine, 320 mL of toluene, 90 mL of ethanol, 21.9 g of potassium carbonate, and 80 mL of water were charged. 1.2 g of tetrakistriphenylphosphine palladium was added and the mixture was stirred under reflux for 13 hours. After cooling, the precipitated solid was collected by filtration and washed under reflux dispersion with 250 mL of methanol and 250 mL of water for 1 hour. 750 mL of toluene was added to the solid obtained by filtration and stirred. The mixture was heated to 100°C to confirm the removal of methanol and water, and then cooled to 80°C. 10 g of silica gel was added and stirred for 1 hour, and the solid was removed by thermal filtration. The filtrate was concentrated, and the resulting residue was purified by crystallization using acetone solvent to obtain 33.0 g of yellowish-white powder of N-([1,1'-biphenyl]-4-yl)-5'-phenyl-[1,1':2',1''-terphenyl]-4-amine (yield: 65.9%).

[0141] In a reaction vessel, 10.2 g of N-([1,1'-biphenyl]-4-yl)-5'-phenyl-[1,1':2',1''-terphenyl]-4-amine, 7.0 g of 1-(4-bromophenyl)-3-phenylnaphthalene, 70 mL of toluene, and 2.8 g of t-butoxysodium were charged. 0.1 g of palladium acetate and 0.4 g of a 50% toluene solution of tri(t-butyl)phosphine were added, and the mixture was stirred under reflux for 4 hours. After cooling to room temperature, methanol was added, and the precipitated solid was collected by filtration. To the obtained solid, 300 mL of toluene was added and the mixture was stirred and heated to 80°C. 7 g of silica gel and 7 g of activated clay were added and the mixture was stirred for 1 hour. The solid was removed by thermal filtration, and the filtrate was concentrated. The obtained residue was recrystallized using a dichloromethane / acetone mixed solvent to obtain 10.9 g (yield: 74.2%) of a white powder N-([1,1'-biphenyl]-4-yl)-5'-phenyl-N-(4-(3-phenylnaphthalene-1-yl)phenyl)-[1,1':2',1''-terphenyl]-4-amine (compound (1-103)).

[0142] Regarding the obtained white powder, １ H-NMR (CDCl ３ The following 41 hydrogen signals were detected and their structures identified: δ (ppm) = 8.01–8.03 (2H), 7.94–7.96 (1H), 7.58–7.77 (9H), 7.22–7.53 (25H), 7.08–7.15 (4H).

[0143] Compounds represented by general formula (I), other than those synthesized in Synthesis Examples 1 to 9, can also be synthesized in the same manner as in Synthesis Examples 1 to 9.

[0144] <Measurement 1: Measurement of Melting Point and Glass Transition Point> For each arylamine compound represented by general formula (I) synthesized in Synthesis Examples 1 to 9, the melting point and glass transition point were measured using a high-sensitivity differential scanning calorimeter (Bruker AXS, model: DSC3100SA). The results are shown in Table 1. Note that "-" for the melting point means that no melting point was detected (melting point: none).

[0145] <Measurement 2: Measurement of HOMO level> Using each arylamine compound represented by general formula (1) synthesized in Synthesis Examples 1 to 9, a 100 nm thick vapor-deposited film was prepared on an ITO substrate, and the HOMO energy level (HOMO level, ionization potential) was measured using an ionization potential analyzer (Sumitomo Heavy Industries, Ltd., model: PYS-202). The results are shown in Table 1.

[0146]

[0147] As shown in Table 1, the arylamine compounds represented by general formula (I) synthesized in Synthesis Examples 1 to 9 all had glass transition temperatures of 100°C or higher, confirming that the thin film state was stable. Furthermore, the arylamine compounds represented by general formula (I) exhibited a suitable energy level compared to the HOMO level (5.4 eV) of common hole transport materials such as NPDs and TPDs, indicating that they possess good hole transport capability. From the above, it can be concluded that the arylamine compounds represented by general formula (I) are useful as materials for hole injection layers, hole transport layers, electron blocking layers, or light-emitting layers in organic EL devices, and are compounds that can improve the luminous efficiency, driving voltage, and durability of conventional organic EL devices.

[0148] <Fabrication of Organic EL Devices> [Example 1] As shown in Figure 1, an organic EL device was fabricated by sequentially depositing a hole injection layer 3, a hole transport layer 4, a first electron blocking layer 5, a second electron blocking layer 6, a light-emitting layer 7, an electron transport layer 8, an electron injection layer 9, a cathode 10, and a capping layer 11 onto a glass substrate 1 on which a reflective ITO electrode was pre-formed as a transparent anode 2. The specific procedure is as follows.

[0149] A glass substrate 1, which had been sequentially coated with ITO with a thickness of 50 nm, a reflective silver alloy with a thickness of 100 nm, and ITO with a thickness of 5 nm, was ultrasonically cleaned in isopropyl alcohol for 20 minutes, and then dried on a hot plate heated to 250°C for 10 minutes. Subsequently, after UV ozone treatment for 15 minutes, the ITO-coated glass substrate was placed in a vacuum deposition machine and the pressure was reduced to 0.001 Pa or less. Next, a hole injection layer 3 with a thickness of 10 nm was formed by binary deposition of an electron acceptor (Acceptor-1) and a compound (HTM-1) with the following structure, covering the transparent anode 2, at a deposition rate ratio of Acceptor-1:HTM-1 = 3:97. On the hole injection layer 3, a hole transport layer 4 was formed by depositing compound (HTM-1) to a thickness of 140 nm. A first electron blocking layer 5 was formed on the hole transport layer 4 by depositing the following compound (HTM-2) to a thickness of 25 nm. A second electron blocking layer 6 was formed on the first electron blocking layer 5 by depositing the compound (1-4) synthesized in Synthesis Example 1 to a thickness of 5 nm. A light-emitting layer 7 with a thickness of 30 nm was formed on the second electron blocking layer 6 by binary deposition of the following compound (EMD-1) and the aforementioned compound (3-1) at a deposition rate where the deposition rate ratio of compound (EMD-1):compound (3-1) = 5:95. An electron transport layer 8 with a thickness of 30 nm was formed on the light-emitting layer 7 by binary deposition of the following compound (ETM-1) and the following compound (ETM-2) at a deposition rate where the deposition rate ratio of compound (ETM-1):compound (ETM-2) = 50:50. An electron injection layer 9 with a thickness of 1 nm was formed by depositing the compound (ETM-2) on the electron transport layer 8. A magnesium-silver alloy was deposited on the electron injection layer 9 to a thickness of 12 nm as the cathode 10. Finally, an organic EL element was fabricated by depositing a compound (CPL-1) with the structure shown below to a thickness of 60 nm to form a capping layer 11. The compound (3-1) used as the host material was synthesized by a known method as described above.

[0150]

[0151] [Examples 2-144] Organic EL elements according to Examples 2-144 were fabricated in the same manner as in Example 1, except that the compounds shown in Tables 2-1 to 2-6 were used instead of the compounds (1-4) used as the material for the second electron blocking layer 6 and the compound (3-1) used as the material for the light-emitting layer 7.

[0152] [Comparative Example 1] For comparison, an organic EL element was fabricated in the same manner as in Example 1, except that a compound (HTM-3) with the following structure was used instead of compound (1-4) as the material for the second electron blocking layer 6.

[0153] [Comparative Example 2] For comparison, an organic EL element was fabricated in the same manner as in Example 1, except that a compound (HTM-4) with the following structure was used instead of compound (1-4) as the material for the second electron blocking layer 6.

[0154] [Comparative Example 3] For comparison, an organic EL element was fabricated in the same manner as in Example 1, except that a compound (EMH-1) with the following structure was used instead of compound (3-1) as the material for the light-emitting layer 7.

[0155] [Comparative Example 4] For comparison, an organic EL element was fabricated in the same manner as in Example 1, except that a compound (EMH-2) with the following structure was used instead of compound (3-1) as the material for the light-emitting layer 7.

[0156]

[0157] The luminescence characteristics of the organic EL elements fabricated in Examples 1 to 144 and Comparative Examples 1 to 4 were evaluated when a DC voltage was applied in air at room temperature (current density: 10 mA / cm²). ２ ). Furthermore, the device lifetime was measured using the fabricated organic EL element. In this invention, the device lifetime is defined as the luminescence brightness at the start of light emission (initial brightness) of 2000 cd / m². ２ When driven with a constant current, the luminous intensity is 1900 cd / m². ２ The time it took for the brightness to decay to 95% (corresponding to 95% of the initial brightness, which is set to 100%: 95% decay) was measured. The measurement results are summarized in Tables 2-1 to 2-6.

[0158]

[0159]

[0160]

[0161]

[0162]

[0163]

[0164] As shown in Tables 2-1 to 2-6, the current density is 10 mA / cm². ２ The drive voltage for the elements in Examples 1 to 144 was 3.58 to 3.80 V, which is lower than that of the elements in Comparative Examples 1 to 4 (3.88 to 4.01 V). The luminous efficiency of the elements in Examples 1 to 144 was 50.02 to 59.81 cd / A, which is higher than that of the elements in Comparative Examples 1 to 4 (46.10 to 49.21 cd / A). In terms of power efficiency, the elements in Examples 1 to 144 were 42.33 to 51.42 lm / W, which is higher than that of the elements in Comparative Examples 1 to 4 (36.36 to 39.81 lm / W). Furthermore, the element lifespan (95% decay) was 402 to 508 hours for the elements in Examples 1 to 144, compared to 323 to 366 hours for the elements in Comparative Examples 1 to 4, demonstrating a significant improvement in lifespan.

[0165] As is clear from the above results, it was confirmed that arylamine compounds having a specific structure represented by general formula (I) have higher hole mobility and superior electron blocking ability compared to conventional arylamine compounds used as hole transport materials. Furthermore, it was found that by combining them with arylamine compounds represented by general formula (III) as a host material, it is possible to realize organic EL elements with higher luminous efficiency and longer lifespan compared to conventional organic EL elements.

[0166] Although several preferred embodiments of the present invention have been described in detail above, it should be understood that the present invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit or scope of the appended claims.

[0167] This application claims priority based on Japanese Patent Application No. 2024-205561, filed on 26 November 2024, and all of its contents are incorporated herein by reference.

[0168] The organic EL element of the present invention, which uses an arylamine compound having a specific structure, can simultaneously achieve improved luminous efficiency and durability, making it possible to apply it to, for example, home appliances and lighting applications. Furthermore, the arylamine compound of the present invention can be widely used not only in organic EL elements but also in various electronic device fields such as electrophotographic photoreceptors, image sensors, photoelectric conversion elements, and solar cells.

[0169] 1. Glass substrate 2. Transparent anode 3. Hole injection layer 4. Hole transport layer 5. First electron blocking layer 6. Second electron blocking layer 7. Emitting layer 8. Electron transport layer 9. Electron injection layer 10. Cathode 11. Capping layer

Claims

1. In an organic electroluminescence device having an anode, a hole transport layer, an electron blocking layer, a light emitting layer, an electron transport layer, and a cathode in this order, the organic electroluminescence device in which the electron blocking layer contains an arylamine compound represented by the following general formula (I) and the light emitting layer contains a compound represented by the following general formula (III): In the general formula (I), L １ ~L ３ each independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group, and Ar １ ~Ar ３ each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. However, one or two selected from Ar １ ~Ar ３ represents a substituted phenyl group represented by the following general formula (II), and at least one of L １ ~L ３ bonded to the substituted phenyl group is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, In the general formula (II), Ar ４ and Ar ５ each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, and R １ represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. n represents an integer of 0 to 3. When n is 2 or more, a plurality of R １ may be the same as or different from each other. When n is 1 or more, R １ and the R １ A benzene ring to which is bonded, and multiple adjacent R １ Allies, R １ and Ar ４ , and R １ and Ar ５ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, and * represents L in general formula (I). １ ~L ３ This represents the connection point, In general formula (III), L ４ ~L ６ Each of these independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group, Ar ６ ~Ar ８ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, where Ar ６ ~Ar ８ At least one selected from represents a condensed polycyclic aromatic group represented by the following general formulas (IV-1) to (IV-8): In general formulas (IV-1) to (IV-8), X and Y are each independently -CR ５ R ６ -, -NR ７ -, -O-, or -S-, where in general formulas (IV-5) to (IV-8), at least one of X and Y is -CR ５ R ６ - or -O- represents R ２ ~R ４ Each of these independently represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ２ ~R ４ is the R ２ ~R ４ Each of these may be bonded to a benzene ring, and may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, R ５ ~R ７ Each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ５ and R ６ The elements may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, where p represents an integer from 0 to 7, q represents an integer from 0 to 4, and r represents an integer from 0 to 5, and there are multiple R elements when p, q, and r are each independently 2 or more. ２ ~R ４ These may be the same or different from each other, and may be multiple adjacent Rs. ２ ~R ４ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, and * represents L in general formula (III). ４ ~L ６ This represents the connection point.

2. In the above general formula (I), Ar １ L is a substituted phenyl group represented by the general formula (II), １ The organic electroluminescent element according to claim 1, wherein n is one or a combination of one or two arylene groups and / or heteroarylene groups selected from the group consisting of substituted or unsubstituted phenylene groups, biphenylylene groups, terphenylylene groups, naphthylene groups, anthrylene groups, phenanthrylene groups, fluorenylene groups, pyridinediyl groups, thiophendiyl groups, and dibenzofrangliyl groups, and n in the general formula (II) is 0.

3. In the above general formula (I), Ar １ is a substituted phenyl group represented by the general formula (II), and in the general formula (II), Ar ４ and Ar ５ The organic electroluminescent element according to claim 1, wherein each of the groups is independently an aryl group or heteroaryl group selected from the group consisting of a substituted or unsubstituted phenyl group, a naphthyl group, a phenanthryl group, and a thienyl group.

4. In the above general formula (I), Ar １ is a substituted phenyl group represented by the general formula (II), and Ar ２ and Ar ３ At least one of the groups is an aryl group selected from the group consisting of a substituted or unsubstituted phenyl group, naphthyl group, phenanthryl group, fluorenyl group, spirobifluorenyl group, and triphenylenyl group, and L is bonded to the aryl group. ２ and / or L ３ The organic electroluminescent element according to claim 1, wherein each is independently a single bond, or a combination of one or two arylene groups selected from the group consisting of phenylene groups, biphenylylene groups, and naphthylene groups, which are substituted or unsubstituted.

5. In the above general formula (I), L １ ~L ３ The organic electroluminescent element according to claim 1, wherein each is independently a combination of one or two arylene groups selected from the group consisting of phenylene groups, biphenylylene groups, and naphthylene groups, either single-bonded or substituted or unsubstituted.

6. In the above general formula (III), Ar ６ However, it is a condensed polycyclic aromatic group represented by the general formula (IV-1), (IV-2), or (IV-3), L ４ However, the phenylene group is a single bond, substituted or unsubstituted, and in the general formula (IV-1), (IV-2), or (IV-3), X is -CR ５ R ６ - The organic electroluminescent element according to claim 1.

7. In the above general formula (III), Ar ６ However, it is a condensed polycyclic aromatic group represented by the general formula (IV-5) or (IV-6), L ４ However, it is a single bond or a substituted or unsubstituted phenylene group, and in the general formula (IV-5) or (IV-6), X is -CR ５ R ６ The organic electroluminescent element according to claim 1, wherein Y is -O-.

8. The organic electroluminescent element according to any one of claims 1 to 7, wherein the electron blocking layer has a two-layer structure comprising a first electron blocking layer in contact with the hole transport layer and a second electron blocking layer in contact with the light-emitting layer, and the second electron blocking layer contains an arylamine compound represented by the general formula (I).

9. The organic electroluminescent element according to any one of claims 1 to 7, wherein the maximum wavelength of the emission spectrum when a DC voltage is applied to the organic electroluminescent element in air at 25°C is 600 nm or more and 700 nm or less.

10. An electronic element or electronic device having a pair of electrodes and at least two organic layers sandwiched between the pair of electrodes, wherein at least one of the organic layers contains an arylamine compound represented by the following general formula (I), and the other organic layer in contact with the organic layer containing the arylamine compound represented by general formula (I) contains a compound represented by the following general formula (III): In general formula (I), L １ ~L ３ Each of these independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group, Ar １ ~Ar ３ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, where Ar １ ~Ar ３ One or two selected from represent a substituted phenyl group represented by the following general formula (II), and L bonded to the substituted phenyl group. １ ~L ３ At least one of them is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, In general formula (II), Ar ４ and Ar ５ Each of these independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, R １ R represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group, where n is an integer from 0 to 3, and multiple R groups exist when n is 2 or more. １ These can be the same or different from each other, and if n is 1 or greater, R １ and the R １ -bonded benzene ring, a plurality of adjacent R １ to each other, R １ and Ar ４ , and R １ and Ar ５ may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring. * represents L in the general formula (I) １ ~L ３ represents the bonding part with, In the general formula (III), L ４ ~L ６ each independently represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group. Ar ６ ~Ar ８ each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, provided that at least one selected from Ar ６ ~Ar ８ represents a condensed polycyclic aromatic group represented by the following general formulas (IV-1) to (IV-8), In the general formulas (IV-1) to (IV-8), X and Y each independently represent -CR ５ R ６ -, -NR ７ -, -O-, or -S-, provided that in the general formulas (IV-5) to (IV-8), at least one of X and Y represents -CR ５ R ６ - or -O-. R ２ ~R ４ Each of these independently represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ２ ~R ４ is the R ２ ~R ４ Each of these may be bonded to a benzene ring, and may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, R ５ ~R ７ Each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted linear or branched alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted linear or branched alkenyl group having 2 to 6 carbon atoms, a substituted or unsubstituted linear or branched alkyloxy group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyloxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted aryloxy group. ５ and R ６ The elements may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, where p represents an integer from 0 to 7, q represents an integer from 0 to 4, and r represents an integer from 0 to 5, and there are multiple R elements when p, q, and r are each independently 2 or more. ２ ~R ４ These may be the same or different from each other, and may be multiple adjacent Rs. ２ ~R ４ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring, and * represents L in general formula (III). ４ ~L ６ This represents the connection point.

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