Multiple host materials and organic electroluminescent device comprising same

Abstract

Provided are a plurality of host materials and an organic electroluminescent device including the same. The present disclosure relates to a plurality of host materials comprising at least one first host compound represented by Formula 1 and at least one second host compound represented by Formula 2: HAr-(L1-Ar1) a---(1) # imgabs0 #, and an organic electroluminescent device comprising the plurality of host materials, the plurality of host materials comprising at least one first host compound represented by Formula 1 and at least one second host compound represented by Formula 2: HAr-(L1-Ar1) a---(1) # imgabs0 #

Description

[0001] This divisional application of a patent for invention is a divisional application of the patent for invention application with international application number PCT / KR2019 / 007865, national application number 201980048182.0, filing date of June 28, 2019, and title of "Multiple host materials and an organic electroluminescent device including the same". Technical Field

[0002] The present disclosure relates to multiple host materials and an organic electroluminescent device including the same. Background Art

[0003] An electroluminescent device (EL device) is a self-luminous display device, and its advantages are that it provides a wider viewing angle, a greater contrast ratio, and a faster response time. The first organic EL device was developed by Eastman Kodak in 1987 by using small aromatic diamine molecules and an aluminum complex as materials for forming a light-emitting layer [Appl. Phys. Lett. 51, 913, 1987].

[0004] An organic EL device (OLED) converts electrical energy into light by applying electric power to an organic electroluminescent material, and generally includes an anode, a cathode, and an organic layer formed between the two electrodes. The organic layer of the organic EL device may include a hole injection layer, a hole transport layer, a hole assisting layer, a light-emitting assisting layer, an electron blocking layer, a light-emitting layer (containing a host material and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc. The materials used in the organic layer can be classified into a hole injection material, a hole transport material, a hole assisting material, a light-emitting assisting material, an electron blocking material, a light-emitting material, an electron buffer material, a hole blocking material, an electron transport material, an electron injection material, etc. depending on their functions. In such an organic EL device, holes from the anode and electrons from the cathode are injected into the light-emitting layer by applying a voltage, and excitons with high energy are generated by the recombination of holes and electrons. The organic light-emitting compound emits light by moving energy to an excited state and by the energy when the organic light-emitting compound returns from the excited state to the ground state.

[0005] The most important factor determining the luminous efficiency in an organic EL device is the luminescent material. The luminescent material is required to have the following characteristics: high quantum efficiency, high electron and hole mobilities, and uniformity and stability of the formed luminescent material layer. The luminescent materials are classified into blue, green, and red luminescent materials according to the emission color, and further include yellow or orange luminescent materials. In addition, in terms of function, the luminescent materials are classified into host materials and dopant materials. Recently, an urgent task is to develop organic EL devices with high efficiency and long life. In particular, considering the EL characteristics required for medium and large OLED panels, there is an urgent need to develop highly excellent luminescent materials superior to conventional materials. For this purpose, preferably, as a solvent and energy emitter in the solid state, the preferred characteristics of the host material should have high purity and a suitable molecular weight for deposition under vacuum. In addition, the host material is required to have a high glass transition temperature and pyrolysis temperature to achieve thermal stability, high electrochemical stability to achieve long life, easy formability of an amorphous thin film, good adhesion to adjacent layers, and immobility between layers.

[0006] The luminescent material can be used as a combination of a host and a dopant to improve color purity, luminous efficiency, and stability. Generally, a device having excellent EL characteristics has a structure including a luminescent layer formed by doping a dopant into a host. When using such a dopant / host material system as the luminescent material, since the host material greatly affects the efficiency and life of the EL device, their selection is important.

[0007] Korean Patent Publication No. 2018-0012709A discloses a compound having a fused structure as a host material, the fused structure including indolocarbazole and azepine; however, the reference does not specifically disclose a plurality of host materials having a specific combination as in the present disclosure. Summary of the Invention

[0008] Technical Problem

[0009] An object of the present disclosure is, first, to provide a plurality of host materials capable of producing an organic electroluminescent device having a low driving voltage and / or high luminous efficiency and / or long life, and second, to provide an organic electroluminescent device including these host materials.

[0010] Solution to the Problem

[0011] As a result of in-depth research to solve the above technical problems, the inventors of the present invention found that the above object can be achieved by a plurality of host materials including at least one first host compound represented by Formula 1 and at least one second host compound represented by Formula 2, so as to complete the present invention.

[0012] HAr-(L1-Ar1) a---(1)

[0013] In Formula 1,

[0014] HAr represents a substituted or unsubstituted nitrogen-containing (3- to 10-membered) heteroaryl;

[0015] L1 represents a single bond, or a substituted or unsubstituted (C6-C30) arylene;

[0016] Ar1 represents a substituted or unsubstituted (C6-C30) aryl;

[0017] a represents an integer from 1 to 3; and

[0018] when a is 2 or greater, each (L1-Ar1) can be the same or different.

[0019]

[0020] In Formula 2,

[0021] L2 represents a single bond, a substituted or unsubstituted (C1-C30) alkylene, a substituted or unsubstituted (C3-C30) cycloalkylene, a substituted or unsubstituted (C6-C30) arylene, or a substituted or unsubstituted (3- to 30-membered) heteroarylene;

[0022] Ar represents hydrogen, deuterium, halogen, cyano, a substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C3-C30) cycloalkyl, a substituted or unsubstituted (C3-C30) cycloalkenyl, a substituted or unsubstituted (3- to 7-membered) heterocycloalkyl, a substituted or unsubstituted (C6-C30) aryl, a substituted or unsubstituted (3- to 30-membered) heteroaryl, -NR 16 R 17 、or -SiR 18 R 19 R 20 ; or can be connected to adjacent substituents to form a ring;

[0023] R 16 to R 20 each independently represents a substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C6-C30) aryl, or a substituted or unsubstituted (3- to 30-membered) heteroaryl; and

[0024] is represented by Formula 2-1 or 2-2 below.

[0025]

[0026] In Formulas 2-1 and 2-2,

[0027] X1 to X25 each independently represents N or CR a ; and

[0028] R a each independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be linked to an adjacent substituent to form a ring.

[0029] Advantages of the present invention

[0030] By using various host materials according to the present disclosure, an organic electroluminescent device having a low driving voltage and / or a high luminous efficiency and / or a long lifespan can be fabricated. Detailed embodiments

[0031] Hereinafter, the present disclosure will be described in detail. However, the following description is intended to explain the present invention and does not mean to limit the scope of the present invention in any way.

[0032] The present disclosure relates to various host materials and an organic electroluminescent device including these host materials, the various host materials including at least one first host compound represented by Formula 1 and at least one second host compound represented by Formula 2.

[0033] As used herein, "organic electroluminescent material" means a material that can be used in an organic electroluminescent device and may include at least one compound. If necessary, the organic electroluminescent material may be included in any layer constituting the organic electroluminescent device. For example, the organic electroluminescent material may be a hole injection material, a hole transport material, a hole assisting material, a luminescence assisting material, an electron blocking material, a luminescent material (including a host material and a dopant material), an electron buffer material, a hole blocking material, an electron transport material, or an electron injection material, etc.

[0034] As used herein, "multiple host materials" refers to host materials that are a combination of at least two compounds, which can be included in any light-emitting layer constituting an organic electroluminescent device. It can refer to both the material before being included in the organic electroluminescent device (e.g., before vapor deposition) and the material after being included in the organic electroluminescent device (e.g., after vapor deposition). In one embodiment, the multiple host materials of the present disclosure can be a combination of at least two host materials, and optionally, can additionally include conventional materials included in organic electroluminescent materials. By methods known in the art, at least two compounds included in the multiple host materials of the present disclosure can be included together in one light-emitting layer or can be included individually in separate light-emitting layers. For example, at least two compounds can be co-evaporated or co-deposited, or evaporated individually.

[0035] As used herein, "(C1-C30)(sub)alkyl" refers to a straight-chain or branched-chain alkyl having 1 to 30 carbon atoms forming the chain, where the number of carbon atoms is preferably 1 to 20, and more preferably 1 to 10. The above alkyl can include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, etc. "(C3-C30)(sub)cycloalkyl" is a monocyclic hydrocarbon or polycyclic hydrocarbon having 3 to 30 carbon atoms in the ring skeleton, where the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkyl can include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc. "(C3-C30)cycloalkenyl" refers to a monocyclic hydrocarbon or polycyclic hydrocarbon having 3 to 30 carbon atoms in the ring skeleton, which has one or more double bonds, where the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkenyl can include cyclopropenyl, cyclobutenyl, cyclopentenyl, etc. "(3- to 7-membered)heterocycloalkyl" is a cycloalkyl having 3 to 7 ring skeleton atoms, preferably 5 to 7 ring skeleton atoms and at least one heteroatom selected from the group consisting of B, N, O, S, Si, and P, preferably from the group consisting of O, S, and N, and includes tetrahydrofuran, pyrrolidine, thiolan, tetrahydropyran, etc. "(C6-C30)(sub)aryl" is a monocyclic or fused-ring group derived from an aromatic hydrocarbon having 6 to 30 carbon atoms in the ring skeleton, where the number of ring skeleton carbon atoms is preferably 6 to 20, more preferably 6 to 15, which can be partially saturated and can include a spiro structure. Specific examples of aryl include phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, dimethylfluorenyl, diphenylfluorenyl, benzofluorenyl, diphenylbenzofluorenyl, dibenzofluorenyl, phenanthrenyl, benzophenanthrenyl, phenylphenanthrenyl, anthracenyl, benzoanthracenyl, indenyl, benzophenanthrenyl, pyrenyl, tetraphenylenyl, perylenyl, yl, benzo groups such as a base, a tetracenyl group, a fluoranthenyl group, a benzo[b]fluoranthenyl group, a tolyl group, a xylyl group, a mesityl group, an isopropylphenyl group, a spiro[fluorene-fluorene] group, a spiro[fluorene-benzo[b]fluorene] group, an azulene group, etc. More specifically, the aryl group may be an o-tolyl group, an m-tolyl group, a p-tolyl group, a 2,3-xylyl group, a 3,4-xylyl group, a 2,5-xylyl group, a mesityl group, an o-isopropylphenyl group, an m-isopropylphenyl group, a p-isopropylphenyl group, a p-tert-butylphenyl group, a p-(2-phenylpropyl)phenyl group, a 4'-methylbiphenyl-4-yl group, a 4''-tert-butyl-p-terphenyl-4-yl group, an o-biphenyl group, an m-biphenyl group, a p-biphenyl group, an o-terphenyl group, an m-terphenyl-4-yl group, an m-terphenyl-3-yl group, an m-terphenyl-2-yl group, a p-terphenyl-4-yl group, a p-terphenyl-3-yl group, a p-terphenyl-2-yl group, an m-quaterphenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-fluorenyl group, a 2-fluorenyl group, a 3-fluorenyl group, a 4-fluorenyl group, a 9-fluorenyl group, a 9,9-dimethyl-1-fluorenyl group, a 9,9-dimethyl-2-fluorenyl group, a 9,9-dimethyl-3-fluorenyl group, a 9,9-dimethyl-4-fluorenyl group, a 9,9-diphenyl-1-fluorenyl group, a 9,9-diphenyl-2-fluorenyl group, a 9,9-diphenyl-3-fluorenyl group, a 9,9-diphenyl-4-fluorenyl group, a 1-anthracenyl group, a 2-anthracenyl group, a 9-anthracenyl group, a 1-phenanthrenyl group, a 2-phenanthrenyl group, a 3-phenanthrenyl group, a 4-phenanthrenyl group, a 9-phenanthrenyl group, a 1- group, 2- group, 3- group, 4- group, 5- group, 6- group, a benzo[c]phenanthrenyl group, a benzo[g] a group consisting of a phenyl group, a 1-benzophenanthryl group, a 2-benzophenanthryl group, a 3-benzophenanthryl group, a 4-benzophenanthryl group, a 3-fluoranthenyl group, a 4-fluoranthenyl group, an 8-fluoranthenyl group, a 9-fluoranthenyl group, a benzo[a]fluoranthenyl group, and the like. The "(3- to 30-membered) hetero(arylene) group" is an aryl group having 3 to 30 ring backbone atoms, preferably 5 to 25 ring backbone atoms, including at least one, preferably 1 to 4 heteroatoms selected from the group consisting of B, N, O, S, Si, P, and Ge. The above heteroaryl group may be a monocyclic ring or a fused ring condensed with at least one benzene ring; and may be partially saturated. The above heteroatoms may be linked to a substituent selected from the group consisting of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (5- to 30-membered) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted tris(C1-C30)alkylsilyl, substituted or unsubstituted bis(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tris(C6-C30)arylsilyl, substituted or unsubstituted mono- or di-(C1-C30)alkylamino, substituted or unsubstituted mono- or di-(C6-C30)arylamino, and substituted or unsubstituted (C1-C30)alkyl(C6-30)arylamino. In addition, the above heteroaryl group may be a heteroaryl group formed by linking at least one heteroaryl group or aryl group to a heteroaryl group via one or more single bonds; and may contain a spiro structure. Specific examples of the heteroaryl group may include monocyclic heteroaryl groups, which include furyl, thienyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and the like; and fused-ring heteroaryl groups, which include benzofuryl, benzothienyl, isobenzofuryl, dibenzofuryl, dibenzothienyl, benzimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, imidazopyridyl, isoindolyl, indolyl, benzoindolyl, indazolyl, benzothiadiazolyl, quinolinyl, isoquinolinyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, azacarbazolyl, benzocarbazolyl, dibenzocarbazolyl, phenoxazinyl, phenanthridinyl, benzodioxolyl, indolizidinyl, acrylidinyl, silafluorene, germafluorene, and the like. More specifically, the heteroaryl group may be 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 6-pyrimidinyl, 1,2,3-triazin-4-yl, 1,2,4-triazin-3-yl,1,3,5-triazin-2-yl, 1-imidazolyl, 2-imidazolyl, 1-pyrazolyl, 1-indolizidinyl, 2-indolizidinyl, 3-indolizidinyl, 5-indolizidinyl, 6-indolizidinyl, 7-indolizidinyl, 8-indolizidinyl, 2-imidazopyridinyl, 3-imidazopyridinyl, 5-imidazopyridinyl, 6-imidazopyridinyl, 7-imidazopyridinyl, 8-imidazopyridinyl, 1-indolyl, 2-indolyl, 3-indolyl, 4-indolyl, 5-indolyl, 6-indolyl, 7-indolyl, 1-isoindolyl, 2-isoindolyl, 3-isoindolyl, 4-isoindolyl, 5-isoindolyl, 6-isoindolyl, 7-isoindolyl, 2-furyl, 3-furyl, 2-benzofuryl, 3-benzofuryl, 4-benzofuryl, 5-benzofuryl, 6-benzofuryl, 7-benzofuryl, 1-iso-benzofuryl, 3-iso-benzofuryl, 4-iso-benzofuryl, 5-iso-benzofuryl, 6-iso-benzofuryl, 7-iso-benzofuryl, 2-quinolyl, 3-quinolyl, 4-quinolyl, 5-quinolyl, 6-quinolyl, 7-quinolyl, 8-quinolyl, 1-isoquinolyl, 3-isoquinolyl, 4-isoquinolyl, 5-isoquinolyl, 6-isoquinolyl, 7-isoquinolyl, 8-isoquinolyl, 2-quinoxalinyl, 5-quinoxalinyl, 6-quinoxalinyl, 1-carbazolyl, 2-carbazolyl, 3-carbazolyl, 4-carbazolyl, 9-carbazolyl, azacarbazol-1-yl, azacarbazol-2-yl, azacarbazol-3-yl, azacarbazol-4-yl, azacarbazol-5-yl, azacarbazol-6-yl, azacarbazol-7-yl, azacarbazol-8-yl, azacarbazol-9-yl, 1-phenanthridinyl, 2-phenanthridinyl, 3-phenanthridinyl, 4-phenanthridinyl, 6-phenanthridinyl, 7-phenanthridinyl, 8-phenanthridinyl, 9-phenanthridinyl, 10-phenanthridinyl, 1-acridinyl, 2-acridinyl, 3-acridinyl, 4-acridinyl, 9-acridinyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 2-oxadiazolyl, 5-oxadiazolyl, 3-furazanyl, 2-thienyl, 3-thienyl, 2-methylpyrrol-1-yl, 2-methylpyrrol-3-yl, 2-methylpyrrol-4-yl, 2-methylpyrrol-5-yl, 3-methylpyrrol-1-yl, 3-methylpyrrol-2-yl, 3-methylpyrrol-4-yl, 3-methylpyrrol-5-yl, 2-tert-butylpyrrol-4-yl, 3-(2-phenylpropyl)pyrrol-1-yl, 2-methyl-1-indolyl, 4-methyl-1-indolyl, 2-methyl-3-indolyl, 4-methyl-3-indolyl, 2-tert-butyl-1-indolyl, 4-tert-butyl-1-indolyl, 2-tert-butyl-3-indolyl, 4-tert-butyl-3-indolyl, 1-dibenzofuranyl, 2-dibenzofuranyl, 3-dibenzofuranyl, 4-dibenzofuranyl, 1-dibenzothiophenyl, 2-dibenzothiophenyl, 3-dibenzothiophenyl, 4-dibenzothiophenyl, 1-silafluorenyl,2-silylfluorenyl, 3-silylfluorenyl, 4-silylfluorenyl, 1-germanylfluorenyl, 2-germanylfluorenyl, 3-germanylfluorenyl, 4-germanylfluorenyl, etc. In this text, "halogen" includes F, Cl, Br, and I.

[0036] In addition, "ortho (o)", "meta (m)", and "para (p)" mean the substitution positions of all substituents. The ortho position is a compound having substituents adjacent to each other, for example, at the 1- and 2-positions of benzene. The meta position is the next substitution position adjacent to the adjacent substitution positions. For example, the compound has substituents at the 1- and 3-positions on benzene. The para position is the next substitution position after the meta position. For example, the compound has substituents at the 1- and 4-positions on benzene.

[0037] In this text, "a substituted or unsubstituted ring formed by connecting adjacent substituents" means a substituted or unsubstituted (3- to 30-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof formed by connecting or fusing two or more adjacent substituents; preferably, it can be a substituted or unsubstituted (3- to 26-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof. In addition, at least one carbon atom in the formed ring can be replaced by at least one heteroatom selected from the group consisting of B, N, O, S, Si, and P, preferably N, O, and S. According to one embodiment, the ring formed by connecting adjacent substituents can be a (5- to 20-membered) polycyclic aromatic ring, which may contain at least one heteroatom selected from the group consisting of N, O, and S.

[0038] In addition, "substituted" in the expression "substituted or unsubstituted" means that a hydrogen atom in a certain functional group is replaced by another atom or functional group (i.e., a substituent). In HAr, L1, Ar1, L2, Ar, R 16 to R 20 and R aIn the formula, the substituents of the substituted (C1-C30)(sub)alkyl, substituted (C6-C30)(sub)aryl, substituted (3- to 30-membered) hetero(sub)aryl, substituted (C3-C30)(sub)cycloalkyl, substituted (C3-C30) cycloalkenyl, substituted (3- to 7-membered) heterocycloalkyl, substituted (C1-C30) alkoxy, substituted tris(C1-C30) alkylsilyl, substituted bis(C1-C30) alkyl(C6-C30) arylsilyl, substituted (C1-C30) alkylbis(C6-C30) arylsilyl, substituted tris(C6-C30) arylsilyl, substituted mono- or di-(C1-C30) alkylamino, substituted mono- or di-(C6-C30) arylamino, and substituted (C1-C30) alkyl(C6-C30) arylamino are each independently at least one selected from the group consisting of: deuterium, halogen, cyano, carboxyl, nitro, hydroxy, (C1-C30) alkyl, halo(C1-C30) alkyl, (C2-C30) alkenyl, (C2-C30) alkynyl, (C1-C30) alkoxy, (C1-C30) alkylthio, (C3-C30) cycloalkyl, (C3-C30) cycloalkenyl, (3- to 7-membered) heterocycloalkyl, (C6-C30) aryloxy, (C6-C30) arylthio, (C6-C30) aryl-substituted or unsubstituted (5- to 30-membered) heteroaryl, (5- to 30-membered) heteroaryl-substituted or unsubstituted (C6-C30) aryl, tris(C1-C30) alkylsilyl, tris(C6-C30) arylsilyl, bis(C1-C30) alkyl(C6-C30) arylsilyl, (C1-C30) alkylbis(C6-C30) arylsilyl, amino, mono- or di-(C1-C30) alkylamino, (C1-C30) alkyl-substituted or unsubstituted mono- or di-(C6-C30) arylamino, (C1-C30) alkyl(C6-C30) arylamino, (C1-C30) alkylcarbonyl, (C1-C30) alkoxycarbonyl, (C6-C30) arylcarbonyl, bis(C6-C30) arylboronyl, bis(C1-C30) alkylboronyl, (C1-C30) alkyl(C6-C30) arylboronyl, (C6-C30) aryl(C1-C30) alkyl, and (C1-C30) alkyl(C6-C30) aryl. For example, the substituent may be substituted or unsubstituted methyl, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted diphenylamino, or substituted or unsubstituted phenylbiphenylamino.

[0039] Hereinafter, a host material according to an embodiment will be described.

[0040] The host material according to the present disclosure includes at least one first host compound represented by Formula 1 above and at least one second host compound represented by Formula 2 above; and according to one embodiment, the host material may be included in the light-emitting layer of an organic electroluminescent device.

[0041] According to one embodiment, the first host compound as the host material may be represented by Formula 1 below.

[0042] HAr-(L1-Ar1) a ---(1)

[0043] In Formula 1,

[0044] HAr represents a substituted or unsubstituted nitrogen-containing (3- to 10-membered) heteroaryl;

[0045] L1 represents a single bond, or a substituted or unsubstituted (C6-C30) arylene;

[0046] Ar1 represents a substituted or unsubstituted (C6-C30) aryl;

[0047] a represents an integer from 1 to 3; and

[0048] when a is 2 or greater, each (L1-Ar1) may be the same or different.

[0049] In one embodiment, HAr may be a substituted or unsubstituted nitrogen-containing (5- to 10-membered) heteroaryl, preferably an unsubstituted nitrogen-containing (6- to 10-membered) heteroaryl. For example, HAr may be pyrimidinyl, triazinyl, quinolinyl, quinoxalinyl, or quinazolinyl.

[0050] In one embodiment, L1 may be a single bond, or a substituted or unsubstituted (C6-C25) arylene, preferably a single bond or an unsubstituted (C6-C20) arylene. For example, L1 may be a single bond, naphthyl- or fluorene-substituted or unsubstituted phenylene, m-biphenylene, p-biphenylene, naphthylene, phenyl-substituted or unsubstituted fluorenylene, or phenyl-substituted or unsubstituted benzofluorenylene.

[0051] In one embodiment, Ar1 can be a substituted or unsubstituted (C6-C25) aryl group, preferably a (C1-C6) alkyl- or (C6-C18) aryl-substituted or unsubstituted (C6-C18) aryl group. For example, Ar1 can be a fluorenyl-substituted or unsubstituted phenyl group, m-biphenyl, p-biphenyl, naphthyl, m-terphenyl, p-terphenyl, benzophenanthryl, phenanthryl, at least one phenyl- or at least one methyl-substituted fluorenyl (e.g., phenylfluorenyl, diphenylfluorenyl, or dimethylfluorenyl), or at least one phenyl- or at least one methyl-substituted benzofluorenyl (e.g., dimethylbenzofluorenyl or diphenylbenzofluorenyl).

[0052] In one embodiment, a can be an integer of 2 or 3, where each (L1-Ar1) can be the same or different.

[0053] The compound represented by Formula 1 can be represented by the following Formula 1-1 or 1-2.

[0054]

[0055] In Formulas 1-1 and 1-2,

[0056] Y1 to Y6 and Z1 to Z4 each independently represent CR4 or N, provided that at least one of Y1 to Y6 represents N, and at least one of Z1 to Z4 represents N;

[0057] Each R4 independently represents hydrogen, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C2-C30) alkenyl group, or a substituted or unsubstituted (C6-C30) aryl group; or may be linked to an adjacent substituent to form a ring; and

[0058] L1, Ar1, and a are as defined in Formula 1.

[0059] In one embodiment, in Formula 1-1, at least one of Y1 to Y6 can be N, preferably, at least two of Y1 to Y6 can be N, more preferably, at least three of Y1 to Y6 can be N. For example, the compound represented by Formula 1-1 can be a (L1-Ar1) a -substituted pyrimidine or triazine.

[0060] In one embodiment, in Formula 1-2, at least one of Z1 to Z4 can be N, preferably, at least two of Z1 to Z4 can be N. For example, the compound represented by Formula 1-2 can be a (L1-Ar1) a -substituted quinoline, quinoxaline, or quinazoline.

[0061] In one embodiment, each R4 independently represents hydrogen, a substituted or unsubstituted (C1-C20) alkyl group, a substituted or unsubstituted (C2-C20) alkenyl group, or a substituted or unsubstituted (C6-C18) aryl group; or two adjacent R4s may be connected to each other to form a substituted or unsubstituted (3-membered to 30-membered) monocyclic or polycyclic ring. Preferably, hydrogen or two adjacent R4s may be connected to each other to form an unsubstituted (3-membered to 18-membered) monocyclic or polycyclic ring. More preferably, hydrogen or two adjacent R4s may be connected to each other to form an unsubstituted (3-membered to 10-membered) monocyclic ring. For example, each R4 independently represents hydrogen or two adjacent R4s may be fused to each other to form an unsubstituted benzene ring.

[0062] According to one embodiment, the first host compound represented by Formula 1 may be illustrated by the following compounds, but is not limited thereto:

[0063]

[0064]

[0065]

[0066]

[0067]

[0068] The compound of Formula 1 according to the present disclosure can be produced by synthetic methods known to those skilled in the art. For example, the compounds represented by Formula 1-1 or 1-2 can be synthesized with reference to the following Reaction Scheme 1 or 2, but are not limited thereto:

[0069] [Reaction Scheme 1]

[0070]

[0071] [Reaction Scheme 2]

[0072]

[0073] In Reaction Schemes 1 and 2, L1, Ar1, and a are as defined in Formula 1, and Y1 to Y6 and Z1 to Z4 are as defined in Formulas 1-1 and 1-2.

[0074] As described above, exemplary synthetic examples of the compounds represented by Formula 1-1 or 1-2 according to one embodiment are described, but they are based on Buchwald-Hartwig cross-coupling reaction, N-arylation reaction, acidified montmorillonite (H-mont)-mediated etherification reaction, Miyaura borylation reaction, Suzuki cross-coupling reaction, intramolecular acid-induced cyclization reaction, Pd(II)-catalyzed oxidative cyclization reaction, Grignard reaction, Heck reaction, ring dehydration reaction, SN1 substitution reaction, SN2 substitution reaction, phosphine-mediated reductive cyclization reaction, etc. Those skilled in the art will understand that the above reactions will proceed even if other substituents defined in Formula 1-1 or 1-2 in addition to the substituents described in the specific synthetic examples are bonded.

[0075] According to one embodiment, a second host compound as another host material may be represented by Formula 2 below.

[0076]

[0077] In Formula 2,

[0078] L2 represents a single bond, a substituted or unsubstituted (C1-C30) alkylene, a substituted or unsubstituted (C6-C30) arylene, a substituted or unsubstituted (3- to 30-membered) heteroarylene, or a substituted or unsubstituted (C3-C30) cycloalkylene;

[0079] Ar represents hydrogen, deuterium, halogen, cyano, a substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C3-C30) cycloalkyl, a substituted or unsubstituted (C3-C30) cycloalkenyl, a substituted or unsubstituted (3- to 7-membered) heterocycloalkyl, a substituted or unsubstituted (C6-C30) aryl, a substituted or unsubstituted (3- to 30-membered) heteroaryl, -NR 16 R 17 、or -SiR 18 R 19 R 20 ; or may be connected to adjacent substituents to form a ring;

[0080] R 16 to R 20 each independently represents a substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C6-C30) aryl, or a substituted or unsubstituted (3- to 30-membered) heteroaryl; and

[0081] is represented by Formula 2-1 or 2-2 below.

[0082]

[0083] In Formulas 2-1 and 2-2,

[0084] X1 to X 25 each independently represents N or CR a ; and

[0085] R a each independently represents hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3- to 30-membered) heteroaryl, substituted or unsubstituted (C3-C30)cycloalkyl, substituted or unsubstituted (C1-C30)alkoxy, substituted or unsubstituted tris(C1-C30)alkylsilyl, substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tris(C6-C30)arylsilyl, substituted or unsubstituted mono- or di-(C1-C30)alkylamino, substituted or unsubstituted mono- or di-(C6-C30)arylamino, or substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino; or may be linked to adjacent substituents to form a ring.

[0086] In one embodiment, L2 may be a single bond, substituted or unsubstituted (C6-C30)arylene, or substituted or unsubstituted (3- to 30-membered) heteroarylene, preferably a single bond, substituted or unsubstituted (C6-C25)arylene, or substituted or unsubstituted (5- to 25-membered) heteroarylene, more preferably a single bond, substituted or unsubstituted (C6-C18)arylene, or substituted or unsubstituted (5- to 18-membered) heteroarylene. For example, L2 may be a single bond, or substituted or unsubstituted phenylene, substituted or unsubstituted o-biphenylene, substituted or unsubstituted m-biphenylene, substituted or unsubstituted p-biphenylene, substituted or unsubstituted naphthylene, or substituted or unsubstituted carbazolylene.

[0087] In one embodiment, Ar may be hydrogen, deuterium, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (3- to 30-membered) heteroaryl, preferably hydrogen, deuterium, substituted or unsubstituted (C6-C25)aryl, or substituted or unsubstituted (5- to 25-membered) heteroaryl, more preferably substituted or unsubstituted (C6-C18)aryl or substituted or unsubstituted (5- to 18-membered) heteroaryl.

[0088] Specifically, Ar can be a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted o - biphenyl group, a substituted or unsubstituted m - biphenyl group, a substituted or unsubstituted p - biphenyl group, a substituted or unsubstituted naphthylphenyl group, a substituted or unsubstituted phenylnaphthyl group, a substituted or unsubstituted o - terphenyl group, a substituted or unsubstituted m - terphenyl group, a substituted or unsubstituted p - terphenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzocarbazolyl group, a substituted or unsubstituted dibenzocarbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted benzothiophenyl group, a substituted or unsubstituted benzonaphthothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted benzofuranyl group, a substituted or unsubstituted benzonaphthofuranyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted benzofluorenyl group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted phenylbiphenylamino group, a substituted or unsubstituted naphthylphenylamino group, a substituted or unsubstituted naphthylbiphenylamino group, a substituted or unsubstituted biphenylamino group, a substituted or unsubstituted biphenylfluorenylamino group, or a substituted or unsubstituted biphenyldibenzofuranylamino group. For example, Ar can be a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted o - biphenyl group, a substituted or unsubstituted m - biphenyl group, a substituted or unsubstituted p - biphenyl group, a substituted or unsubstituted o - terphenyl group, a substituted or unsubstituted m - terphenyl group, a substituted or unsubstituted p - terphenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted benzofluorenyl group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted phenylbiphenylamino group, or a substituted or unsubstituted naphthylphenylamino group.

[0089] According to one embodiment, in Formula 2, can be represented by Formula 2 - 1 below.

[0090]

[0091] In Formula 2 - 1,

[0092] X1 to X 12 each independently represents N or CR a ; and

[0093] R aEach independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be connected to an adjacent substituent to form a ring.

[0094] In one embodiment, R a may each independently be hydrogen, deuterium, or a substituted or unsubstituted (C6-C30) aryl group; or may be connected to an adjacent substituent to form a ring, preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C25) aryl group; or may be connected or fused to an adjacent substituent to form a substituted or unsubstituted (3- to 30-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C18) aryl group; or may be connected or fused to an adjacent substituent to form a substituted or unsubstituted (5- to 30-membered) monocyclic or polycyclic aromatic ring, or a combination thereof. For example, R a may each independently be hydrogen or a substituted or unsubstituted phenyl group; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

[0095] In one embodiment, X1 and X2 may each independently be CR a wherein R a may be fused to each other to form a benzene ring.

[0096] Specifically, according to one embodiment, Formula 2-1 may be represented by Formula 2-1-1.

[0097]

[0098] In Formula 2-1-1,

[0099] R 41 to R 43Each independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be linked to an adjacent substituent to form a ring;

[0100] ba represents an integer from 1 to 3, bb represents an integer from 1 to 4, and bc represents an integer from 1 to 5; and

[0101] When ba, bb, and bc are 2 or greater, each R 41 、each R 42 or each R 43 may be the same or different.

[0102] In one embodiment, R 41 to R 43 may each independently be hydrogen, deuterium, or a substituted or unsubstituted (C6-C30) aryl group; or may be linked to an adjacent substituent to form a ring, preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C25) aryl group; or may be linked or fused to an adjacent substituent to form a substituted or unsubstituted (3- to 30-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C18) aryl group; or may be linked or fused to an adjacent substituent to form a substituted or unsubstituted (5- to 30-membered) monocyclic or polycyclic aromatic ring, or a combination thereof. For example, R 41 to R 43 may each independently be hydrogen or a substituted or unsubstituted phenyl group; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

[0103] According to another embodiment, in Formula 2, may be represented by Formula 2-2 below.

[0104]

[0105] In Formula 2-2,

[0106] X 13 to X25 each independently represents N or CR a ; and

[0107] R a each independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be connected to adjacent substituents to form a ring.

[0108] In one embodiment, R a may each independently be hydrogen, deuterium, or a substituted or unsubstituted (C6-C30) aryl group; or may be connected to adjacent substituents to form a ring, preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C25) aryl group; or may be connected or fused to adjacent substituents to form a substituted or unsubstituted (3- to 30-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C18) aryl group; or may be connected or fused to adjacent substituents to form a substituted or unsubstituted (5- to 30-membered) monocyclic or polycyclic aromatic ring, or a combination thereof. For example, R a may each independently be hydrogen or a substituted or unsubstituted phenyl group; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

[0109] In one embodiment, X 15 and X 16 may each independently be CR a wherein R a may be fused to each other to form a benzene ring.

[0110] In one embodiment, X 17 and X 18 may each independently be CR a wherein R a may be fused to each other to form a benzene ring.

[0111] Specifically, according to one embodiment, Formula 2-2 can be represented by Formula 2-2-1.

[0112]

[0113] In Formula 2-2-1,

[0114] R 31 to R 34 each independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be linked to an adjacent substituent to form a ring;

[0115] aa represents an integer from 1 to 3, ab and ac each independently represent an integer from 1 to 4, and ad represents an integer of 1 or 2; and

[0116] when aa, ab, ac, and ad are 2 or greater, each R 31 each R 32 each R 33 or each R 34 may be the same or different.

[0117] In one embodiment, R 31 to R 34 may each independently be hydrogen, deuterium, or a substituted or unsubstituted (C6-C30) aryl group; or may be linked to an adjacent substituent to form a ring, preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C25) aryl group; or may be linked or fused to an adjacent substituent to form a substituted or unsubstituted (3- to 30-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, deuterium, or a substituted or unsubstituted (C6-C18) aryl group; or may be linked or fused to an adjacent substituent to form a substituted or unsubstituted (5- to 30-membered) monocyclic or polycyclic aromatic ring, or a combination thereof. For example, R 41 to R 43 each independently represent hydrogen or a substituted or unsubstituted phenyl group; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

[0118] According to one embodiment, the second host compound represented by Formula 2 can be more specifically illustrated by the following compounds, but is not limited thereto:

[0119]

[0120]

[0121]

[0122] For the compound of Formula 2 according to the present disclosure, specifically, the compound of Formula 2-1 can be synthesized by referring to the method disclosed in Korean Patent Application No. 2018-0021961 (February 23, 2018), and the compound of Formula 2-2 can be synthesized by referring to the method disclosed in Korean Patent Publication No. 2018-0012709 (February 6, 2018), but is not limited thereto. The compound can be produced by another synthesis method known to those skilled in the art.

[0123] Hereinafter, an organic electroluminescent device applying the above-described various host materials will be described.

[0124] The organic electroluminescent device according to the present disclosure includes a first electrode; a second electrode; and at least one organic layer interposed between the first electrode and the second electrode. The organic layer may include a light-emitting layer, and the light-emitting layer may include host materials including at least one first host compound represented by Formula 1 and at least one second host compound represented by Formula 2.

[0125] According to one embodiment, the first host compound represented by Formula 1 and the second host compound represented by Formula 2 may be included in the same organic layer or may be separately included in different organic layers.

[0126] The light-emitting layer is a layer from which light is emitted and may be a single layer or a multi-layer in which two or more layers are stacked. In the light-emitting layer, it is preferable that the doping concentration of the dopant compound based on the host compound is less than 20 wt%, preferably 17 wt%.

[0127] One of the first electrode and the second electrode may be an anode, and the other may be a cathode. Among them, the first electrode and the second electrode may each be formed of a transmissive conductive material, a transmissive reflective conductive material, or a reflective conductive material. Depending on the material types forming the first electrode and the second electrode, the organic electroluminescent device may be a top-emission type, a bottom-emission type, or a side-emission type. The organic layer may include a light-emitting layer and may further include at least one layer selected from the following: a hole injection layer, a hole transport layer, a hole assist layer, a light emission assist layer, an electron transport layer, an electron injection layer, an intermediate layer, a hole blocking layer, an electron blocking layer, and an electron buffer layer.

[0128] The organic layer may further include an amine-based compound and / or an azine-based compound other than the luminescent material according to the present disclosure. Specifically, the hole injection layer, the hole transport layer, the hole assisting layer, the light emitting layer, the light emitting assisting layer, or the electron blocking layer may contain an amine-based compound (e.g., an arylamine-based compound and a styrylarylamine-based compound, etc.) as a hole injection material, a hole transport material, a hole assisting material, a luminescent material, a light emitting assisting material, or an electron blocking material. In addition, the electron transport layer, the electron injection layer, the electron buffer layer, or the hole blocking layer may contain an azine-based compound as an electron transport material, an electron injection material, an electron buffer material, or a hole blocking material.

[0129] In addition, the organic layer may further include at least one metal selected from the group consisting of metals of Group 1 of the periodic table, metals of Group 2, transition metals of the 4th period, transition metals of the 5th period, lanthanides, and organometals of d-transition elements, or at least one complex compound containing such a metal.

[0130] According to one embodiment, the organic electroluminescent material may be used as a luminescent material for a white organic light emitting device. Depending on the arrangement of R (red), G (green), B (blue), or YG (yellowish green) light emitting units, white organic light emitting devices have shown various structures, such as a parallel side-by-side arrangement method, a stacked arrangement method, or a CCM (color conversion material) method, etc. In addition, according to one embodiment, the organic electroluminescent material may also be applied to an organic electroluminescent device including QD (quantum dot).

[0131] A hole injection layer, a hole transport layer, an electron blocking layer, or a combination thereof may be used between the anode and the light emitting layer. The hole injection layer may be multilayered to reduce the hole injection barrier (or hole injection voltage) from the anode to the hole transport layer or the electron blocking layer, and each layer in the multilayer may use two compounds simultaneously. In addition, the hole injection layer may be doped with a p-type dopant. Further, an electron blocking layer may be placed between the hole transport layer (or the hole injection layer) and the light emitting layer, and excitons may be confined within the light emitting layer by blocking the overflow of electrons from the light emitting layer to prevent light leakage. The hole transport layer or the electron blocking layer may be multilayered, and each layer therein may use a variety of compounds.

[0132] An electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, or a combination thereof may be used between the light-emitting layer and the cathode. The electron buffer layer may be multilayered to control the injection of electrons and improve the interfacial characteristics between the light-emitting layer and the electron injection layer, where each multilayer may use two compounds simultaneously. The hole blocking layer or the electron transport layer may also be multilayered, where each layer may use multiple compounds. Additionally, the electron injection layer may be doped with an n-type dopant.

[0133] A light-emission assisting layer may be disposed between the anode and the light-emitting layer, or between the cathode and the light-emitting layer. When the light-emission assisting layer is disposed between the anode and the light-emitting layer, it may be used to facilitate hole injection and / or hole transport, or to prevent electron spillage. When the light-emission assisting layer is disposed between the cathode and the light-emitting layer, it may be used to facilitate electron injection and / or electron transport, or to prevent hole spillage. Additionally, a hole assisting layer may be disposed between the hole transport layer (or hole injection layer) and the light-emitting layer, and may effectively promote or limit the hole transport rate (or hole injection rate), thereby enabling control of charge balance. When the organic electroluminescent device includes two or more hole transport layers, the further included hole transport layer may serve as a hole assisting layer or an electron blocking layer. The light-emission assisting layer, the hole assisting layer, or the electron blocking layer may function to improve the efficiency and / or lifetime of the organic electroluminescent device.

[0134] In the organic electroluminescent device of the present disclosure, at least one layer selected from a chalcogenide layer, a metal halide layer, and a metal oxide layer (hereinafter, "surface layer") may preferably be disposed on one or more inner surfaces of one or both electrodes. Specifically, a chalcogenide (including oxide) layer of silicon and aluminum is preferably disposed on the anode surface of the electroluminescent medium layer, and a metal halide layer or a metal oxide layer is preferably disposed on the cathode surface of the electroluminescent medium layer. The operational stability of the organic electroluminescent device may be obtained through the surface layer. Preferably, the chalcogenide includes SiO X (1 ≤ X ≤ 2), AlO X (1 ≤ X ≤ 1.5), SiON, SiAlON, etc.; the metal halide includes LiF, MgF2, CaF2, rare earth metal fluorides, etc.; and the metal oxide includes Cs2O, Li2O, MgO, SrO, BaO, CaO, etc.

[0135] In addition, in the organic electroluminescent device of the present disclosure, a mixed region of an electron transport compound and a reducing dopant, or a mixed region of a hole transport compound and an oxidizing dopant may be placed on at least one surface of a pair of electrodes. In this case, the electron transport compound is reduced to an anion, and thus it becomes easier to inject and transport electrons from the mixed region to the electroluminescent medium. In addition, the hole transport compound is oxidized to a cation, and thus it becomes easier to inject and transport holes from the mixed region to the electroluminescent medium. Preferably, the oxidizing dopant includes various Lewis acids and acceptor compounds, and the reducing dopant includes alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, and mixtures thereof. In addition, the reducing dopant layer can be used as a charge generation layer to fabricate an organic electroluminescent device having two or more light-emitting layers and emitting white light.

[0136] According to one embodiment, the organic electroluminescent device may further include at least one dopant in the light-emitting layer.

[0137] The dopant included in the organic electroluminescent material of the present disclosure may be at least one phosphorescent dopant or fluorescent dopant, preferably a phosphorescent dopant. The phosphorescent dopant material applied to the organic electroluminescent device of the present disclosure is not particularly limited, but may preferably be a complex compound of one or more metalized one or more metal atoms selected from iridium (Ir), osmium (Os), copper (Cu), and platinum (Pt), more preferably a complex compound of one or more ortho-metalized one or more metal atoms selected from iridium (Ir), osmium (Os), copper (Cu), and platinum (Pt), and even more preferably a complex compound of one or more ortho-metalized iridium complexes.

[0138] The dopant included in the organic electroluminescent device may use the compound represented by Formula 101, but is not limited thereto:

[0139]

[0140] In Formula 101,

[0141] wherein, L is selected from the following Structure 1 or 2:

[0142]

[0143] R 100 to R 103 each independently represents hydrogen, deuterium, halogen, halogen-substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C6-C30) aryl, cyano, substituted or unsubstituted (3-membered to 30-membered) heteroaryl, or substituted or unsubstituted (C1-C30) alkoxy; or R 100 to R103 may be linked to one or more adjacent substituents to form a substituted or unsubstituted fused ring, for example, a substituted or unsubstituted quinoline, a substituted or unsubstituted benzofuropyridine, a substituted or unsubstituted benzothienopyridine, a substituted or unsubstituted indolopyridine, a substituted or unsubstituted benzofuroquinoline, a substituted or unsubstituted benzothienoquinoline, or a substituted or unsubstituted indoloquinoline;

[0144] R 104 to R 107 each independently represents hydrogen, deuterium, a halogen, a halogen-substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C3-C30) cycloalkyl, a substituted or unsubstituted (C6-C30) aryl, a substituted or unsubstituted (3- to 30-membered) heteroaryl, a cyano group, or a substituted or unsubstituted (C1-C30) alkoxy; or R 104 to R 107 may be linked to one or more adjacent substituents to form a substituted or unsubstituted fused ring, for example, a substituted or unsubstituted naphthyl, a substituted or unsubstituted fluorene, a substituted or unsubstituted dibenzothiophene, a substituted or unsubstituted dibenzofuran, a substituted or unsubstituted indolopyridine, a substituted or unsubstituted benzofuropyridine, or a substituted or unsubstituted benzothienopyridine;

[0145] R 111 to R 121 each independently represents hydrogen, deuterium, a halogen, a halogen-substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C3-C30) cycloalkyl, or a substituted or unsubstituted (C6-C30) aryl; or may be linked to one or more adjacent substituents to form a substituted or unsubstituted fused ring; and

[0146] s represents an integer from 1 to 3.

[0147] Specific examples of the dopant compound include, but are not limited to, the following:

[0148]

[0149]

[0150]

[0151]

[0152] To form each layer of the organic electroluminescent device of the present disclosure, dry film-forming methods such as vacuum evaporation, sputtering, plasma, ion plating methods, etc., or wet film-forming methods such as inkjet printing, nozzle printing, slot coating, spin coating, dip coating, flow coating methods, etc. can be used. When using a wet film-forming method, a thin film can be formed by dissolving or diffusing the material for forming each layer into any suitable solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc. The solvent can be any solvent in which the material for forming each layer can be dissolved or diffused and which has no problem in film-forming ability.

[0153] When forming a layer from a dopant and the host compound of the present disclosure, co-evaporation or co-evaporation of a mixture can be used.

[0154] Co-deposition is a co-deposition method in which two or more isomeric materials are placed in corresponding individual crucible sources and current is applied to two chambers simultaneously to evaporate the materials and perform mixed deposition; and mixed deposition is a co-deposition method in which two or more isomeric materials are mixed in one crucible source before deposition and then current is applied to one chamber to evaporate the materials.

[0155] According to one embodiment, the organic electroluminescent device of the present disclosure can be used to manufacture display devices such as smartphones, tablet computers, laptop computers, PCs, TVs, or display devices for vehicles, or lighting devices such as outdoor or indoor lighting.

[0156] Hereinafter, a method for preparing an organic electroluminescent device containing a plurality of host materials according to the present disclosure and its characteristics will be explained in order to understand the present disclosure in detail.

[0157] [Device Examples 1 to 8] Production of an OLED in which the first host compound and a second compound according to the present disclosure are deposited as the host

[0158] An OLED device containing the compound of the present disclosure is produced. First, an indium tin oxide (ITO) thin film (10 Ω / sq) (GEOMATEC CO., LTD., Japan) on a glass substrate for the OLED device is subjected to ultrasonic washing successively with acetone, ethanol, and distilled water, and then stored in isopropyl alcohol. Then the ITO substrate is mounted on a substrate holder of a vacuum vapor deposition apparatus. Compound HI-1 is introduced into the chamber of the vacuum vapor deposition apparatus, and then the pressure in the chamber of the apparatus is controlled to 10 -6Support. Thereafter, an electric current is applied to the chamber to evaporate the above-introduced material, thereby forming a first hole injection layer with a thickness of 80 nm on the ITO substrate. Next, compound HI-2 is introduced into another chamber of the vacuum vapor deposition apparatus, and the compound is evaporated by applying an electric current to the chamber, thereby forming a second hole injection layer with a thickness of 5 nm on the first hole injection layer. Then, compound HT-1 is introduced into another chamber of the vacuum vapor deposition apparatus, and the compound is evaporated by applying an electric current to the chamber, thereby forming a first hole transport layer with a thickness of 10 nm on the second hole injection layer. Then, compound HT-2 is introduced into another chamber of the vacuum vapor deposition apparatus, and the compound is evaporated by applying an electric current to the chamber, thereby forming a second hole transport layer with a thickness of 60 nm on the first hole transport layer. After forming the hole injection layer and the hole transport layer, a light-emitting layer is formed thereon as follows: The first host compound and the second host compound in Table 1 below are introduced as hosts into one chamber of the vacuum vapor deposition apparatus, and compound RD-39 is introduced as a dopant into another chamber. The two host materials are evaporated at different rates and the dopant is deposited at a doping amount of 3 wt%, so as to form a light-emitting layer with a thickness of 40 nm on the hole transport layer. Next, compounds ET-1 and EI-1 are evaporated and deposited at a rate of 1:1, so as to form an electron transport layer with a thickness of 35 nm on the light-emitting layer. After depositing compound EI-1 as an electron injection layer with a thickness of 2 nm on the electron transport layer, an Al cathode with a thickness of 80 nm is deposited on the electron injection layer through another vacuum vapor deposition apparatus. Thus, an OLED is produced.

[0159] [Comparative Examples 1 and 2] Production of OLEDs Containing Compounds Not According to the Present Disclosure

[0160] Except for using the compounds in Table 1 below as hosts respectively, OLEDs are produced in the same manner as in the Device Example.

[0161] The results of the driving voltage, luminous efficiency, power efficiency, and the time (lifetime; T80) taken to decrease from 100% to 80% at a brightness of 5,000 nits of the organic electroluminescent devices of Device Examples 1 to 8 and Comparative Examples 1 and 2 produced as described above are shown in Table 1 below.

[0162] Table 1

[0163]

[0164]

[0165] Referring to Table 1 above, it was confirmed that the organic electroluminescent device containing a specific combination compound according to an embodiment as a host material has improved characteristics in terms of driving voltage, efficiency, and / or lifetime compared to a conventional organic electroluminescent device.

[0166] The compounds used in the device examples and comparative examples are shown in Table 2 below.

[0167] Table 2

[0168]

Claims

1. A plurality of host materials, comprising at least one first host compound and at least one second host compound, wherein the first host compound is represented by Formula 1 and the second host compound is represented by Formula 2: HAr-(L1-Ar1) a ---(1) Wherein, HAr represents a substituted or unsubstituted nitrogen-containing (3- to 10-membered) heteroaryl; L1 represents a single bond, or a substituted or unsubstituted (C6-C30) arylene; Ar1 represents a substituted or unsubstituted (C6-C30) aryl; Wherein (C6-C30) aryl represents a substituted or unsubstituted phenyl, a substituted or unsubstituted biphenyl, a substituted or unsubstituted terphenyl, a substituted or unsubstituted quaterphenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted binaphthyl, a substituted or unsubstituted phenylnaphthyl, a substituted or unsubstituted naphthylphenyl, a substituted or unsubstituted phenanthryl, at least one methyl-substituted or unsubstituted fluorenyl, at least one phenyl- or at least one methyl-substituted benzofluorenyl; a represents an integer from 1 to 3; and When a is 2 or greater, each (L1-Ar1) can be the same or different; Wherein, L2 represents a single bond, a substituted or unsubstituted (C1-C30) alkylene, a substituted or unsubstituted (C3-C30) cycloalkylene, a substituted or unsubstituted (C6-C30) arylene, or a substituted or unsubstituted (3- to 30-membered) heteroarylene; Ar represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C3-C30) cycloalkenyl group, a substituted or unsubstituted (3- to 7-membered) heterocycloalkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, -NR 16 R 17 、 or -SiR 18 R 19 R 20 ; or may be linked to an adjacent substituent to form a ring; R 16 to R 20 each independently represents a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (3- to 30-membered) heteroaryl group; and represented by the following formula 2-2; Wherein, X 13 to X 25 each independently represents N or CR a ; and R a each independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be linked to an adjacent substituent to form a ring.

2. The main material according to claim 1, wherein Formula 1 is represented by Formula 1-1 or 1-2: Wherein, Y1 to Y6 and Z1 to Z4 each independently represent CR4 or N, provided that at least one of Y1 to Y6 represents N and at least one of Z1 to Z4 represents N; Each R4 independently represents hydrogen, a substituted or unsubstituted (C1-C30) alkyl, a substituted or unsubstituted (C2-C30) alkenyl, or a substituted or unsubstituted (C6-C30) aryl; or can be connected to adjacent substituents to form a ring; L1, Ar1, and a are as defined in claim 1.

3. The main material according to claim 1, wherein, Formula 2-2 is represented by Formula 2-2-1: Wherein, R 31 to R 34 each independently represents hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3- to 30-membered) heteroaryl group, a substituted or unsubstituted (C3-C30) cycloalkyl group, a substituted or unsubstituted (C1-C30) alkoxy group, a substituted or unsubstituted tris(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl group, a substituted or unsubstituted tris(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, a substituted or unsubstituted mono- or di-(C6-C30)arylamino group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group; or may be linked to an adjacent substituent to form a ring; aa represents an integer from 1 to 3, ab and ac each independently represent an integer from 1 to 4, and ad represents an integer of 1 or 2; and When aa, ab, ac, and ad are 2 or greater, each R 31 , each R 32 , each R 33 , or each R 34 can be the same or different.

4. The main material according to claim 1, wherein, Ar represents a substituted or unsubstituted phenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted o - terphenyl, a substituted or unsubstituted m - terphenyl, a substituted or unsubstituted p - terphenyl, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted benzocarbazolyl, a substituted or unsubstituted dibenzocarbazolyl, a substituted or unsubstituted dibenzothiophenyl, a substituted or unsubstituted benzothiophenyl, a substituted or unsubstituted benzonaphthothiophenyl, a substituted or unsubstituted dibenzofuranyl, a substituted or unsubstituted benzofuranyl, a substituted or unsubstituted benzonaphthofuranyl, a substituted or unsubstituted fluorenyl, a substituted or unsubstituted benzofluorenyl, a substituted or unsubstituted spirobifluorenyl, a substituted or unsubstituted diphenylamino, a substituted or unsubstituted phenylterphenylamino, a substituted or unsubstituted naphthylphenylamino, a substituted or unsubstituted naphthylterphenylamino, a substituted or unsubstituted terphenylamino, a substituted or unsubstituted terphenylfluorenylamino, or a substituted or unsubstituted terphenyldibenzofuranylamino.

5. The main material according to claim 1, wherein, The compound represented by Formula 1 is selected from the group consisting of:

6. The main material according to claim 1, wherein, The compound represented by Formula 2 is selected from the group consisting of:

7. An organic electroluminescent device, comprising: An anode, a cathode, and at least one light - emitting layer between the anode and the cathode, wherein the at least one light - emitting layer contains a plurality of host materials according to claim 1.

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