CN112437989A

CN112437989A - Multiple host materials and organic electroluminescent device comprising the same

Info

Publication number: CN112437989A
Application number: CN201980048182.0A
Authority: CN
Inventors: 金宾瑞; 李琇炫; 郑昭永; 韩泰俊; 朴孝淳; 赵相熙; 梁正恩
Original assignee: Rohm and Haas Electronic Materials Korea Ltd
Current assignee: Rohm and Haas Electronic Materials Korea Ltd
Priority date: 2018-07-31
Filing date: 2019-06-28
Publication date: 2021-03-02
Also published as: TW202007764A; KR20200014189A

Abstract

The present disclosure relates to 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, and an organic electroluminescent device including the plurality of host materials. By including the host material, an organic electroluminescent device having a low driving voltage and/or high luminous efficiency and/or a long lifetime can be provided.

Description

Multiple host materials and organic electroluminescent device comprising the same

Technical Field

The present disclosure relates to host materials and an organic electroluminescent device including the same.

Background

An electroluminescent device (EL device) is a self-luminous display device, which is advantageous in 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 aluminum complexes as materials for forming a light emitting layer [ appl. phys. lett. [ appurtenance of physics ]51, 913, 1987 ].

An organic EL device (OLED) converts electrical energy into light by applying 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 assist layer, a light emission assist 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, and the like. Materials used in the organic layer may be classified into a hole injection material, a hole transport material, a hole assist material, a light emission assist 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, and the like, depending on their functions. In such an organic EL device, holes from an anode and electrons from a cathode are injected into a light emitting layer by applying a voltage, and excitons having high energy are generated by recombination of the holes and the electrons. The organic light emitting compound moves to an excited state by energy and emits light by the energy when the organic light emitting compound returns to a ground state from the excited state.

The most important factor determining the luminous efficiency in an organic EL device is a light emitting material. The luminescent material is required to have the following characteristics: high quantum efficiency, high electron and hole mobility, and uniformity and stability of the formed light emitting material layer. The light emitting materials are classified into blue, green and red light emitting materials according to emission colors, and further include yellow or orange light emitting materials. In addition, in terms of functions, the light emitting material is classified into a host material and a dopant material. Recently, development of an organic EL device having high efficiency and long life is an urgent task. In particular, in view of EL characteristics required for medium-and large-sized OLED panels, development of highly excellent light emitting materials superior to conventional materials is urgently required. For this reason, preferably, as the solvent and the energy emitter in a solid state, the preferred characteristics of the host material should have high purity and 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 a long life, easy formability of an amorphous thin film, good adhesion to adjacent layers, and no mobility between layers.

The light emitting material may be used as a combination of a host and a dopant to improve color purity, light emitting efficiency, and stability. In general, a device having excellent EL characteristics has a structure including a light emitting layer formed by doping a dopant into a host. When such dopant/host material systems are used as light emitting materials, their selection is important because the host material greatly affects the efficiency and lifetime of the EL device.

Korean patent publication No. 2018-0012709A discloses a compound having a condensed structure including indolocarbazole and azepine as a host material; however, the reference does not specifically disclose a plurality of host materials having a specific combination as disclosed herein.

Disclosure of Invention

Technical problem

It is an object of the present disclosure to, firstly, provide a plurality of host materials capable of producing an organic electroluminescent device having a low driving voltage and/or a high luminous efficiency, and/or a long life, and, secondly, to provide an organic electroluminescent device comprising these host materials.

Solution to the problem

As a result of intensive studies to solve the above technical problems, the present inventors found that the above object can be achieved by host materials comprising at least one first host compound represented by the following formula 1 and at least one second host compound represented by the following formula 2, so as to complete the present invention.

HAr-(L₁-Ar₁)_a---(1)

In the formula 1, the first and second groups,

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

L₁represents a single bond, or a substituted or unsubstituted (C6-C30) arylene group;

Ar₁represents a substituted or unsubstituted (C6-C30) aryl group;

a represents an integer of 1 to 3; and is

When a is 2 or more, each (L)₁-Ar₁) May be the same or different.

In the formula 2, the first and second groups,

L₂represents a single bond, a substituted or unsubstituted (C1-C30) alkylene group, a substituted or unsubstituted (C3-C30) cycloalkylene group, a substituted or unsubstituted (C6-C30) arylene group, or a substituted or unsubstituted (3-to 30-membered) heteroarylene group;

ar represents hydrogen, tritium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C3-C30) cycloalkenyl, substituted or unsubstituted (3-to 7-membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) arylSubstituted or unsubstituted (3-to 30-membered) heteroaryl, -NR₁₆R₁₇or-SiR₁₈R₁₉R₂₀(ii) a Or may be linked to an adjacent substituent to form a ring;

R₁₆to R₂₀Each 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 is

Represented by the following formula 2-1 or 2-2.

In the formulae 2-1 and 2-2,

X₁to X₂₅Each independently represents N or CR_a(ii) a And is

R_aEach independently represents hydrogen, tritium, 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 tri (C1-C30) alkylsilyl, substituted or unsubstituted di (C1-C30) alkyl (C6-C30) arylsilyl, substituted or unsubstituted (C1-C30) alkyl di (C6-C30) arylsilyl, substituted or unsubstituted tri (C6-C30) arylsilyl, substituted or unsubstituted mono-or di- (C1-C30) alkylamino, substituted or unsubstituted mono-or di- (C6-C30) arylamino, substituted or unsubstituted mono-C6-C30) arylamino, Or a substituted or unsubstituted (C1-C30) alkyl (C6-C30) arylamino group; or may be linked to an adjacent substituent to form a ring.

The invention has the advantages of

By using a plurality of host materials according to the present disclosure, an organic electroluminescent device having a low driving voltage and/or high luminous efficiency and/or a long lifetime can be prepared.

Detailed Description

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

The present disclosure relates to a plurality of host materials including at least one first host compound represented by formula 1 above and at least one second host compound represented by formula 2 above, and an organic electroluminescent device including the host materials.

Herein, the "organic electroluminescent material" means a material that can be used in an organic electroluminescent device and that can contain at least one compound. The organic electroluminescent material may be contained in any layer constituting the organic electroluminescent device, if necessary. For example, the organic electroluminescent material may be a hole injection material, a hole transport material, a hole assist material, a light emission assist material, an electron blocking material, a light emitting material (containing a host material and a dopant material), an electron buffering material, a hole blocking material, an electron transport material, an electron injection material, or the like.

Herein, "a plurality of host materials" means a host material comprising a combination of at least two compounds, which may be included in any light emitting layer constituting an organic electroluminescent device. It may mean both a material before being contained in the organic electroluminescent device (e.g., before vapor deposition) and a material after being contained in the organic electroluminescent device (e.g., after vapor deposition). In one embodiment, the plurality of host materials of the present disclosure may be a combination of at least two host materials, and optionally, may additionally include conventional materials included in the organic electroluminescent material. At least two compounds included in the various host materials of the present disclosure may be included together in one light emitting layer or may be included each in a separate light emitting layer by a method known in the art. For example, at least two compounds may be evaporated in combination or co-evaporated, or separately evaporated.

As used herein, "(C1-C30) (alkylene) refers to a straight or branched chain alkyl group having 1 to 30 carbon atoms making up the chain, which isThe number of carbon atoms is preferably 1 to 20, and more preferably 1 to 10. The above alkyl group may include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl and the like. "(C3-C30) (cyclo) alkylene" is a monocyclic or polycyclic hydrocarbon having 3 to 30 ring skeleton carbon atoms, wherein the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkyl group may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. "(C3-C30) cycloalkenyl" means a monocyclic hydrocarbon or polycyclic hydrocarbon having a cyclic skeleton of 3 to 30 carbon atoms, which has one or more double bonds, wherein the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkenyl group may include cyclopropenyl, cyclobutenyl, cyclopentenyl and the like. "(3-to 7-membered) heterocycloalkyl" is a cycloalkyl group having 3 to 7 ring backbone atoms, preferably 5 to 7 ring backbone atoms, and at least one heteroatom selected from the group consisting of B, N, O, S, Si and P, preferably O, S and N, and includes tetrahydrofuran, pyrrolidine, tetrahydrothiophene (thiolan), tetrahydropyran, and the like. "(C6-C30) (arylene) is a monocyclic or fused ring group derived from an aromatic hydrocarbon having 6 to 30 ring backbone carbon atoms, wherein the number of ring backbone carbon atoms is preferably 6 to 20, more preferably 6 to 15, which may be partially saturated, and may comprise a spiro structure. Examples of the aryl group specifically include phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, dimethylfluorenyl, diphenylfluorenyl, benzofluorenyl, diphenylbenzofluorenyl, dibenzofluorenyl, phenanthryl, benzophenanthryl, phenylphenanthryl, anthryl, benzanthryl, indenyl, benzophenanthryl, pyrenyl, tetracenyl, perylenyl, perylene, dinaphthyl, phenanthryl, phenylnaphthyl, fluorenyl, dibenzofluorenyl, phenanthrenyl, benzophenanthrenyl, phenanthrenyl, pyrenyl, tetrac,

Radical, benzo

Mesityl, tetracenyl, fluoranthenyl, benzofluoranthenyl, tolyl, xylyl, trimethylphenyl, isopropylphenyl, spiro [ fluorene-fluorene]Spiro [ fluorene-benzofluorene ] s]Mesityl, azulene and the like. More specifically, the aryl group may be o-tolyl, m-tolyl, p-tolyl, 23-xylyl group, 3, 4-xylyl group, 2, 5-xylyl group, trimethylphenyl group, o-cumyl group, m-cumyl group, p-tert-butylphenyl group, p- (2-phenylpropyl) phenyl group, 4 '-methylbiphenyl group, 4' -tert-butyl-p-terphenyl-4-yl group, o-biphenyl group, m-biphenyl group, p-terphenyl group, o-terphenyl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m-quaterphenyl group, 1-naphthyl group, 2-naphthyl group, 1-fluorenyl group, 2-fluorenyl group, 3-fluorenyl group, p-terphenyl group, p-, 4-fluorenyl, 9-dimethyl-1-fluorenyl, 9-dimethyl-2-fluorenyl, 9-dimethyl-3-fluorenyl, 9-dimethyl-4-fluorenyl, 9-diphenyl-1-fluorenyl, 9-diphenyl-2-fluorenyl, 9-diphenyl-3-fluorenyl, 9-diphenyl-4-fluorenyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, 9-phenanthryl, 1-

Base 2-

Base 3-

Base, 4-

Base 5-

Base 6-

Radical, benzo [ c]Phenanthryl, benzo [ g ]]

A group such as 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, and a benzofluoranthenyl group. "(3-to 30-membered) hetero (arylene" is a ring having 3 to 30 ring skeletonsAryl of the subgroup in which the number of ring backbone atoms is preferably 5 to 25, includes 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 condensed ring condensed with at least one benzene ring; and may be partially saturated. The above heteroatom may be linked to at least one substituent selected from the group consisting of: hydrogen, tritium, 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 tri (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 tri (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. Further, the above heteroaryl group may be a heteroaryl group formed by connecting at least one heteroaryl group or aryl group to a heteroaryl group via one or more single bonds; and may comprise a spiro structure. Examples of the heteroaryl group may specifically include monocyclic heteroaryl groups including 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 type heteroaryl groups including benzofuranyl, benzothienyl, isobenzofuranyl, dibenzofuranyl, dibenzothiophenyl, benzimidazolyl, benzothiazolyl, benzisothiazolyl, benzisoxazolyl, benzoxazolyl, imidazopyridinyl, isoindolyl, indolyl, benzindolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, azacarbazolyl, benzocarbazolyl, dibenzocarbazolyl, phenoxazinyl, phenanthridinyl, benzodioxolyl, indolizinyl (indolizi)dinyl), acridinyl (arylidinyl), silafluorenyl, germanfluorenyl, and the like. More specifically, the heteroaryl group may be a 1-pyrrolyl group, a 2-pyrrolyl group, a 3-pyrrolyl group, a 2-pyridyl group, a 3-pyridyl group, a 4-pyridyl group, a 2-pyrimidyl group, a 4-pyrimidyl group, a 5-pyrimidyl group, a 6-pyrimidyl group, a 1, 2, 3-triazin-4-yl group, a 1, 2, 4-triazin-3-yl group, a 1, 3, 5-triazin-2-yl group, a 1-imidazolyl group, a 2-imidazolyl group, a 1-pyrazolyl group, a 1-indolizidinyl group, a 2-indolizidinyl group, a 3-indolizidinyl group, a 5-indolizidinyl group, a 6-indolizidinyl group, a 7-indolizidinyl group, an 8-indolizidinyl group, a 2-imidazopyridinyl group, a, 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-isobenzofuryl, 3-isobenzofuranyl group, 4-isobenzofuranyl group, 5-isobenzofuranyl group, 6-isobenzofuranyl group, 7-isobenzofuranyl group, 2-quinolyl group, 3-quinolyl group, 4-quinolyl group, 5-quinolyl group, 6-quinolyl group, 7-quinolyl group, 8-quinolyl group, 1-isoquinolyl group, 3-isoquinolyl group, 4-isoquinolyl group, 5-isoquinolyl group, 6-isoquinolyl group, 7-isoquinolyl group, 8-isoquinolyl group, 2-quinoxalyl group, 5-quinoxalyl group, 6-quinoxalyl group, 1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, 9-carbazolyl group, azacarbazol-1-yl group, azacarbazol-2-yl group, a, 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, 2-phenanthridinyl, etc, 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-silafluorenyl, 3-silafluorenyl, 4-silafluorenyl, 1-germanium fluorenyl, 2-germanium fluorenyl, 3-germanium fluorenyl, 4-germanium fluorenyl, and the like. As used herein, "halogen" includes F, Cl, Br, and I.

Further, "o", "m", and "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 a substitution position next to the substitution position immediately, and for example, the compound has a substituent at the 1-position and the 3-position on benzene. The para position is the next substitution position of the meta position, and for example, the compound has substituents at the 1-and 4-positions on benzene.

Herein, "substituted or unsubstituted ring formed by linking to adjacent substituents" means a substituted or unsubstituted (3-to 30-membered) monocyclic or polycyclic alicyclic ring, aromatic ring, or a combination thereof formed by linking or fusing two or more adjacent substituents; preferably, the alicyclic ring, aromatic ring, or a combination thereof, which may be substituted or unsubstituted (3-to 26-membered) monocyclic or polycyclic. Furthermore, at least one carbon atom in the formed ring may 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 may 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.

Further, the "substituted" in the expression "substituted or unsubstituted" means that in a certain functional groupIs replaced with another atom or functional group (i.e., substituent). HAR, L in formulas 1 and 2₁、Ar₁、L₂、Ar、R₁₆To R₂₀And R_aIn (e), substituted (C1-C30) alkyl (arylene), substituted (C6-C30) aryl (arylene), substituted (3-to 30-membered) hetero (arylene), substituted (C3-C30) cycloalkyl (arylene), substituted (C3-C30) cycloalkenyl, substituted (3-to 7-membered) heterocycloalkyl, substituted (C1-C30) alkoxy, substituted tri (C30-C30) alkylsilyl, substituted di (C30-C30) alkyl (C30-C30) arylsilyl, substituted (C30-C30) alkyldi (C30-C30) arylsilyl, substituted tri (C30-C30) arylsilyl, substituted mono-or di- (C30-C30) alkylamino, substituted mono-or di- (C30-C30) arylamino, and substituted C30-C30 (C30) arylamino are each independently selected from the following groups At least one of the group consisting of: tritium, halogen, cyano, carboxyl, nitro, hydroxyl, (C-C) alkyl, halo (C-C) alkyl, (C-C) alkenyl, (C-C) alkynyl, (C-C) alkoxy, (C-C) alkylthio, (C-C) cycloalkyl, (C-C) cycloalkenyl, (3-to 7-membered) heterocycloalkyl, (C-C) aryloxy, (C-C) arylthio, (C-C) aryl-substituted or unsubstituted (5-to 30-membered) heteroaryl, (5-to 30-membered) heteroaryl-substituted or unsubstituted (C-C) aryl, tri (C-C) alkylsilyl, tri (C-C) arylsilyl, di (C-C) alkyl (C-C) arylsilyl, (C-C) alkyldi (C-C) 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, di (C6-C30) arylborarbonyl, di (C1-C30) alkylborarbonyl, (C1-C30) alkyl (C6-C30) arylborarbonyl, (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 naphthyl, substituted or unsubstituted biphenyl, or unsubstituted biphenyl, Substituted or unsubstituted fluorenyl group, substituted or unsubstituted carbazolyl group, substituted or unsubstituted dibenzofuranyl group, substituted or unsubstituted dinaphthyl groupBenzothienyl, substituted or unsubstituted diphenylamino, or substituted or unsubstituted phenylbiphenylamino.

Hereinafter, a body material according to an embodiment will be described.

A 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 a light emitting layer of the organic electroluminescent device.

According to one embodiment, the first host compound as a host material may be represented by the following formula 1.

HAr-(L₁-Ar₁)_a---(1)

In the formula 1, the first and second groups,

Ar₁represents a substituted or unsubstituted (C6-C30) aryl group;

a represents an integer of 1 to 3; and is

When a is 2 or more, each (L)₁-Ar₁) May be the same or different.

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.

In one embodiment, L₁May be a single bond, or a substituted or unsubstituted (C6-C25) arylene group, preferably a single bond or an unsubstituted (C6-C20) arylene group. For example, L₁May be a single bond, a naphthyl-or fluorenyl-substituted or unsubstituted phenylene group, a m-biphenylene group, a p-biphenylene group, a naphthylene group, a phenyl-substituted or unsubstituted fluorenylene group, or a phenyl-substituted or unsubstituted benzofluorenylene group.

In one embodiment, Ar₁May be a substituted or unsubstituted (C6-C25) aryl group, preferablySelected from (C1-C6) alkyl-or (C6-C18) aryl-substituted or unsubstituted (C6-C18) aryl. For example, Ar₁May be a fluorenyl-substituted or unsubstituted phenyl, 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).

In one embodiment, a can be an integer of 2 or 3, each of which (L)₁-Ar₁) May be the same or different.

The compound represented by formula 1 may be represented by the following formula 1-1 or 1-2.

In the formulae 1-1 and 1-2,

Y₁to Y₆And Z₁To Z₄Each independently represent CR4 or N, provided that Y₁To Y₆Represents N, and Z₁To Z₄Represents N;

R₄each 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 is

L₁、Ar₁And a is as defined in formula 1.

In one embodiment, in formula 1-1, Y₁To Y₆May be N, preferably, Y₁To Y₆May be N, more preferably, Y₁To Y₆At least three of which may be N. For example, the compound represented by formula 1-1 may be (L)₁-Ar₁)_a-substituted pyrimidines or triazines.

In one embodiment of the present invention,in the formula 1-2, Z₁To Z₄May be N, preferably, Z₁To Z₄At least two of which may be N. For example, the compound represented by formula 1-2 may be (L)₁-Ar₁)_a-substituted quinolines, quinoxalines, or quinazolines.

In one embodiment, R₄Each 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 R₄May be linked to each other to form a substituted or unsubstituted (3-to 30-membered) monocyclic or polycyclic ring, preferably, hydrogen or two adjacent R₄May be linked to each other to form an unsubstituted (3-to 18-membered) monocyclic or polycyclic ring, more preferably, hydrogen or two adjacent R₄May be linked to each other to form an unsubstituted (3-to 10-membered) monocyclic ring. For example, R₄Each independently represents hydrogen or two adjacent R₄May be fused with each other to form an unsubstituted benzene ring.

According to one embodiment, the first host compound represented by formula 1 may be illustrated by, but is not limited to, the following compounds:

the compound of formula 1 according to the present disclosure may be produced by synthetic methods known to those skilled in the art, for example, the compound represented by formula 1-1 or 1-2 may be synthesized with reference to the following reaction scheme 1 or 2, but is not limited thereto:

[ reaction scheme 1]

[ reaction scheme 2]

In schemes 1 and 2, L₁、Ar₁And a is as defined in formula 1, Y₁To Y₆And Z₁To Z₄Are as defined in formulae 1-1 and 1-2.

As described above, exemplary synthetic examples of the compound represented by formula 1-1 or 1-2 according to one embodiment are described, but they are based on the Buchwald-hartwigh (Buchwald-Hartwig) cross-coupling reaction, N-arylation reaction, acidified montmorillonite (H-mont) -mediated etherification reaction, royal pump (Miyaura) boronation reaction, Suzuki (Suzuki) cross-coupling reaction, intramolecular acid-induced cyclization reaction, pd (ii) -catalyzed oxidative cyclization reaction, Grignard (Grignard) reaction, Heck (Heck) reaction, ring dehydration reaction, SN (g) reaction₁Substitution reaction, SN₂Substitution reactions, phosphine-mediated reductive cyclization reactions, and the like. It will be understood by those skilled in the art that the above reaction proceeds even if other substituents defined in formula 1-1 or 1-2 than the substituents described in the specific synthetic examples are bonded.

According to one embodiment, the second host compound as another host material may be represented by the following formula 2.

In the formula 2, the first and second groups,

L₂represents a single bond, a substituted or unsubstituted (C1-C30) alkylene group, a substituted or unsubstituted (C6-C30) arylene group, a substituted or unsubstituted (3-to 30-membered) heteroarylene group, or a substituted or unsubstituted (C3-C30) cycloalkylene group;

ar represents hydrogen, tritium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C3-C30) cycloalkenyl, substituted or unsubstituted (3-to 7-membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3-to 30-membered) heteroaryl, -NR₁₆R₁₇or-SiR₁₈R₁₉R₂₀(ii) a Or may be linked to an adjacent substituent to form a ring;

Represented by the following formula 2-1 or 2-2.

In the formulae 2-1 and 2-2,

X₁to X₂₅Each independently represents N or CR_a(ii) a And is

R_aEach independently represents hydrogen, tritium, 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 tri (C1-C30) alkylsilyl, substituted or unsubstituted di (C1-C30) alkyl (C6-C30) arylsilyl, substituted or unsubstituted (C1-C30) alkyl di (C6-C30) arylsilyl, substituted or unsubstituted (C366383-C30) alkyl di (C6-C30) arylsilyl, substituted or unsubstitutedA substituted tri (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.

In one embodiment, L₂May be a single bond, a substituted or unsubstituted (C6-C30) arylene group, or a substituted or unsubstituted (3-to 30-membered) heteroaryl group, preferably a single bond, a substituted or unsubstituted (C6-C25) arylene group, or a substituted or unsubstituted (5-to 25-membered) heteroaryl group, more preferably a single bond, a substituted or unsubstituted (C6-C18) arylene group, or a substituted or unsubstituted (5-to 18-membered) heteroarylene group. For example, L₂May be a single bond, or a substituted or unsubstituted phenylene group, a substituted or unsubstituted orthobiphenylene group, a substituted or unsubstituted metabiphenylene group, a substituted or unsubstituted paraphenylene group, a substituted or unsubstituted naphthylene group, or a substituted or unsubstituted carbazolyl group.

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

Specifically, Ar may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted ortho-biphenyl group, a substituted or unsubstituted meta-biphenyl group, a substituted or unsubstituted para-biphenyl group, a substituted or unsubstituted naphthylphenyl group, a substituted or unsubstituted phenylnaphthyl group, a substituted or unsubstituted ortho-terphenyl group, a substituted or unsubstituted meta-terphenyl group, a substituted or unsubstituted para-terphenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzocarbazolyl 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, Substituted or unsubstituted benzofluorenyl group, substituted or unsubstituted spirobifluorenyl group, substituted or unsubstituted diphenylamino group, substituted or unsubstituted phenylbiphenylamino group, substituted or unsubstituted naphthylphenylamino group, substituted or unsubstituted naphthylbiphenylamino group, substituted or unsubstituted biphenylamino group, substituted or unsubstituted biphenylfluorenylamino group, or substituted or unsubstituted biphenyldibenzofuranylamino group, for example, Ar may be substituted or unsubstituted phenyl group, substituted or unsubstituted naphthyl group, substituted or unsubstituted o-biphenyl group, substituted or unsubstituted m-biphenyl group, substituted or unsubstituted p-biphenylyl group, substituted or unsubstituted o-terphenyl group, substituted or unsubstituted m-terphenyl group, substituted or unsubstituted p-terphenyl group, substituted or unsubstituted carbazolyl group, substituted or unsubstituted dibenzothienyl group, substituted or unsubstituted dibenzofuranyl 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.

According to one embodiment, in formula 2,

can be represented by the following formula 2-1.

In the formula 2-1, the compound represented by the formula,

X₁to X₁₂Each independently represents N or CR_a(ii) a And is

R_aEach independently represents hydrogen, tritium, 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 unsubstitutedA tri (C1-C30) alkylsilyl, a substituted or unsubstituted di (C1-C30) alkyl (C6-C30) arylsilyl, a substituted or unsubstituted (C1-C30) alkyldi (C6-C30) arylsilyl, a substituted or unsubstituted tri (C6-C30) arylsilyl, a substituted or unsubstituted mono-or di- (C1-C30) alkylamino, a substituted or unsubstituted mono-or di- (C6-C30) arylamino, or a substituted or unsubstituted (C1-C30) alkyl (C6-C30) arylamino; or may be linked to an adjacent substituent to form a ring.

In one embodiment, R_aMay each independently be hydrogen, tritium, or a substituted or unsubstituted (C6-C30) aryl group; or may be linked to an adjacent substituent to form a ring, preferably hydrogen, tritium, or a substituted or unsubstituted (C6-C25) aryl group; or are linked or fused to an adjacent substituent to form a substituted or unsubstituted (3-to 30-membered), mono-or polycyclic, alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, tritium, or a substituted or unsubstituted (C6-C18) aryl group; or may be linked to 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_aMay each independently be hydrogen or substituted or unsubstituted phenyl; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

In one embodiment, X₁And X₂May each independently be CR_aWherein R is_aMay be fused with each other to form a benzene ring.

Specifically, according to one embodiment, formula 2-1 may be represented by formula 2-1-1.

In the formula 2-1-1,

R₄₁to R₄₃Each independently represents hydrogen, tritium, 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, or a pharmaceutically acceptable salt thereofA substituted or unsubstituted tri (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 tri (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;

ba represents an integer of 1 to 3, bb represents an integer of 1 to 4, and bc represents an integer of 1 to 5; and is

When ba, bb, and bc are 2 or more, each R₄₁Each R₄₂Or each R₄₃May be the same or different.

In one embodiment, R₄₁To R₄₃May each independently be hydrogen, tritium, or a substituted or unsubstituted (C6-C30) aryl group; or may be linked to an adjacent substituent to form a ring, preferably hydrogen, tritium, or a substituted or unsubstituted (C6-C25) aryl group; or are linked or fused to an adjacent substituent to form a substituted or unsubstituted (3-to 30-membered), mono-or polycyclic, alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, tritium, or a substituted or unsubstituted (C6-C18) aryl group; or an aromatic ring linked or fused to an adjacent substituent to form a substituted or unsubstituted (5-to 30-membered) monocyclic or polycyclic ring, or a combination thereof. For example, R₄₁To R₄₃May each independently be hydrogen or substituted or unsubstituted phenyl; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

According to another embodiment, in formula 2,

can be represented by the following formula 2-2.

In the formula 2-2, the first and second groups,

X₁₃to X₂₅Each independently represents N or CR_a(ii) a And is

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

In one embodiment, X₁₅And X₁₆May each independently be CR_aWherein R is_aMay be fused with each other to form a benzene ring.

In one embodiment, X₁₇And X₁₈May each independently be CR_aWherein R is_aMay be fused with each other to form a benzene ring.

Specifically, according to one embodiment, formula 2-2 may be represented by formula 2-2-1.

In the formula 2-2-1,

R₃₁to R₃₄Each independently represents hydrogen, tritium, 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 tri (C1-C30) alkylsilyl, substituted or unsubstituted di (C1-C30) alkyl (C6-C30) arylsilyl, substituted or unsubstituted (C1-C30) alkyl di (C6-C30) arylsilyl, substituted or unsubstituted tri (C6-C30) arylsilyl, substituted or unsubstituted mono-or di- (C1-C30) alkylamino, substituted or unsubstituted mono-or di- (C6-C30) arylamino, substituted or unsubstituted mono-C6-C30) arylamino, 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 of 1 to 3, ab and ac each independently represent an integer of 1 to 4, and ad represents an integer of 1 or 2; and is

When aa, ab, ac, and ad are 2 or greater, each R₃₁Each R₃₂Each R₃₃Or each R₃₄May be the same or different.

In one embodiment, R₃₁To R₃₄May each independently be hydrogen, tritium, or a substituted or unsubstituted (C6-C30) aryl group; or may be linked to an adjacent substituent to form a ring, preferably hydrogen, tritium, or a substituted or unsubstituted (C6-C25) aryl group; or are linked or fused to an adjacent substituent to form a substituted or unsubstituted (3-to 30-membered), mono-or polycyclic, alicyclic ring, aromatic ring, or a combination thereof, more preferably hydrogen, tritium, or a substituted or unsubstituted (C6-C18) aryl group; or may be linked to 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, R₄₁To R₄₃Each independently representHydrogen or substituted or unsubstituted phenyl; or may be fused to each other to form a substituted or unsubstituted aromatic ring.

According to one embodiment, the second host compound represented by formula 2 may be more specifically illustrated by, but not limited to, the following compounds:

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(2018, 2/23), and the compound of formula 2-2 can be synthesized by referring to the method disclosed in korean patent publication No. 2018-0012709(2018, 2/6), but is not limited thereto. The compounds may be produced by another synthetic method known to those skilled in the art.

Hereinafter, an organic electroluminescent device to which the above-described various host materials are applied will be described.

An 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.

According to one embodiment, the first host compound represented by formula 1 and the second host compound represented by formula 2 may be contained in the same organic layer or may be contained in different organic layers, respectively.

The light emitting layer is a layer from which light is emitted, and may be a single layer or a multilayer 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 may be less than 20 wt%, preferably 17 wt%.

One of the first electrode and the second electrode may be an anode, and the other may be a cathode. Wherein the first electrode and the second electrode may be each formed as a transmissive conductive material, a transflective conductive material, or a reflective conductive material. The organic electroluminescent device may be a top emission type, a bottom emission type, or a both-side emission type according to the kind of materials forming the first electrode and the second electrode. The organic layer may include a light emitting layer, and may further include at least one layer selected from the group consisting of: 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.

The organic layer may further include an amine-based compound and/or an azine-based compound in addition to the light-emitting material according to the present disclosure. Specifically, the hole injection layer, the hole transport layer, the hole assist layer, the light emitting layer, the light emission assist layer, or the electron blocking layer may contain an amine-based compound (e.g., an arylamine-based compound, a styrylarylamine-based compound, or the like) as a hole injection material, a hole transport material, a hole assist material, a light emitting material, a light emission assist 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.

In addition, the organic layer may further include at least one metal selected from the group consisting of: an organometallic of a metal of group 1, a metal of group 2, a transition metal of period 4, a transition metal of period 5, a lanthanide and a d-transition element of the periodic table, or at least one complex compound comprising such a metal.

According to one embodiment, an organic electroluminescent material may be used as a light emitting material for a white organic light emitting device. The white organic light emitting device has been suggested various structures such as a parallel side-by-side arrangement method, a stack arrangement method, or a CCM (color conversion material) method, etc., according to the arrangement of R (red), G (green), B (blue), or YG (yellow-green) light emitting cells. Further, according to an embodiment, the organic electroluminescent material may also be applied to an organic electroluminescent device including QDs (quantum dots).

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 a multilayer to lower a hole injection barrier (or hole injection voltage) from the anode to the hole transport layer or the electron blocking layer, wherein each of the multiple layers may use two compounds at the same time. In addition, the hole injection layer may be doped with a p-type dopant. In addition, an electron blocking layer may be disposed 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 electrons from overflowing from the light emitting layer to prevent light emission leakage. The hole transport layer or the electron blocking layer may be a multilayer, and a plurality of compounds may be used for each layer.

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 a plurality of layers to control injection of electrons and improve interfacial characteristics between the light emitting layer and the electron injection layer, wherein two compounds may be simultaneously used for each plurality of layers. The hole blocking layer or the electron transporting layer may also be a multilayer, in which a plurality of compounds may be used for each layer. In addition, the electron injection layer may be doped with n-type dopants.

The 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 a light-emitting auxiliary layer is placed between the anode and the light-emitting layer, it can be used to facilitate hole injection and/or hole transport, or to prevent electron overflow. When the light-emitting auxiliary layer is placed between the cathode and the light-emitting layer, it may be used to facilitate electron injection and/or electron transport, or to prevent hole overflow. In addition, a hole assist layer may be disposed between the hole transport layer (or hole injection layer) and the light emitting layer, and the hole transport rate (or hole injection rate) may be effectively promoted or limited, thereby enabling control of charge balance. When the organic electroluminescent device includes two or more hole transport layers, the hole transport layers further included may serve as a hole assist layer or an electron blocking layer. The light-emitting auxiliary layer, the hole auxiliary layer, or the electron blocking layer may have an effect of improving the efficiency and/or lifetime of the organic electroluminescent device.

In the organic electroluminescent device of the present disclosure, at least one layer (hereinafter, "surface layer") selected from a chalcogenide layer, a halogenated metal layer, and a metal oxide layer may be preferably 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 can be obtained by the surface layer. Preferably, the chalcogenide comprises SiO_X(1≤X≤2)、AlO_X(X is more than or equal to 1 and less than or equal to 1.5), SiON, SiAlON and the like; the metal halide includes LiF, MgF₂、CaF₂Rare earth metal fluorides, etc.; and the metal oxide comprises Cs₂O、Li₂O, MgO, SrO, BaO, CaO, etc.

Further, in the organic electroluminescent device of the present disclosure, a mixed region of an electron transport compound and a reductive dopant, or a mixed region of a hole transport compound and an oxidative dopant may be disposed 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-transporting compound is oxidized into cations, 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 reductive dopant layer may be used as a charge generation layer to prepare an organic electroluminescent device having two or more light emitting layers and emitting white light.

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

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 be preferably a complex compound of one or more metallized metal atoms selected from iridium (Ir), osmium (Os), copper (Cu), and platinum (Pt), more preferably one or more ortho-metallized complex compounds of one or more metal atoms selected from iridium (Ir), osmium (Os), copper (Cu), and platinum (Pt), and even more preferably one or more ortho-metallized iridium complex compounds.

The dopant contained in the organic electroluminescent device may use a compound represented by the following formula 101, but is not limited thereto:

in the formula 101, the first and second groups,

wherein L is selected from the following structures 1 or 2:

R₁₀₀to R₁₀₃Each independently represents hydrogen, tritium, halogen-substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C6-C30) aryl, cyano, substituted or unsubstituted (3-to 30-membered) heteroaryl, or substituted or unsubstituted (C1-C30) alkoxy; or R₁₀₀To R₁₀₃May be linked to one or more adjacent substituents to form a substituent orUnsubstituted fused rings, for example, substituted or unsubstituted quinoline, substituted or unsubstituted benzofuropyridine, substituted or unsubstituted benzothienopyridine, substituted or unsubstituted indenopyridine, substituted or unsubstituted benzofuroquinoline, substituted or unsubstituted benzothienoquinoline, or substituted or unsubstituted indenoquinoline;

R₁₀₄to R₁₀₇Each independently represents hydrogen, tritium, halogen-substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3-to 30-membered) heteroaryl, cyano, or substituted or unsubstituted (C1-C30) alkoxy; or R₁₀₄To R₁₀₇May be linked to one or more adjacent substituents to form a substituted or unsubstituted fused ring, for example, substituted or unsubstituted naphthyl, substituted or unsubstituted fluorene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofuran, substituted or unsubstituted indenopyridine, substituted or unsubstituted benzofuropyridine, or substituted or unsubstituted benzothienopyridine;

R₁₁₁to R₁₂₁Each independently represents hydrogen, tritium, halogen-substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C3-C30) cycloalkyl, or 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 is

s represents an integer of 1 to 3.

Specific examples of dopant compounds include, but are not limited to, the following:

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

When a layer is formed by a dopant and a host compound of the present disclosure, co-evaporation or mixture evaporation may be used.

Co-deposition is a hybrid deposition method in which two or more isomer materials are put into respective single crucible sources and electric current is simultaneously applied to two cells to evaporate the materials and perform hybrid deposition; and hybrid deposition is a hybrid deposition method in which two or more isomer materials are mixed in a crucible source before being deposited and then an electric current is applied to a cell to evaporate the materials.

According to one embodiment, the organic electroluminescent device of the present disclosure may be used to manufacture a display device such as a smart phone, a tablet computer, a notebook computer, a PC, a TV, or a display device for a vehicle, or a lighting device such as outdoor or indoor lighting.

Hereinafter, a method of manufacturing an organic electroluminescent device including a plurality of host materials according to the present disclosure and characteristics thereof will be explained in order to understand the present disclosure in detail.

Device examples 1 to 8 OLEDs in which a first host compound and a second compound according to the present disclosure were deposited as hosts were produced

Producing an OLED device comprising the compounds of the present disclosure. First, a transparent electrode Indium Tin Oxide (ITO) thin film (10 Ω/sq) (geomae co., LTD., japan) on a glass substrate for an OLED device was subjected to ultrasonic washing with acetone, ethanol, and distilled water in this order, and then stored in isopropyl alcohol. The ITO substrate was then mounted on a substrate holder of a vacuum vapor deposition apparatus. Introducing the compound HI-1 into a chamber of a vacuum vapor deposition apparatus, and then controlling the pressure in the chamber of the apparatus to 10^-6And (4) supporting. Thereafter, a current was applied to the cell to evaporate the above-introduced material, thereby forming a first hole injection layer having a thickness of 80nm on the ITO substrate. Next, the compound HI-2 was introduced into another cell of the vacuum vapor deposition apparatus, and the compound was evaporated by applying a current to the cell, thereby forming a second hole injection layer having a thickness of 5nm on the first hole injection layer. Then, the compound HT-1 was introduced into another cell of the vacuum vapor deposition apparatus, and the compound was evaporated by applying a current to the cell, thereby forming a first hole transport layer having a thickness of 10nm on the second hole injection layer. Then, the compound HT-2 was introduced into another cell of the vacuum vapor deposition apparatus, and the compound was evaporated by applying a current to the cell, thereby forming a second hole transport layer having a thickness of 60nm 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 of table 1 below were introduced as hosts into one cell of the vacuum vapor deposition apparatus, and the compound RD-39 was introduced as a dopant into the other cell. The two host materials were evaporated at different rates and a dopant was deposited at a doping amount of 3 wt% to form a light emitting layer having a thickness of 40nm on the hole transport layer. Next, the compounds ET-1 and EI-1 were evaporated at a rate of 1: 1 and deposited to form an electron transport layer having a thickness of 35nm on the light emitting layer. After depositing the compound EI-1 as an electron injection layer having a thickness of 2nm on the electron transport layer, a deposition tool was deposited on the electron injection layer by another vacuum vapor deposition apparatusThere is an Al cathode with a thickness of 80 nm. Thus, an OLED was produced.

Comparative examples 1 and 2 production of OLEDs comprising Compounds not according to the present disclosure

OLEDs were produced in the same manner as in the device examples, except that the compounds of table 1 below were used as hosts, respectively.

The results of the driving voltage, the light emitting efficiency, the power efficiency, and the time taken for the organic electroluminescent devices of device examples 1 to 8 and comparative examples 1 and 2, produced as described above, to decrease from 100% to 80% at a luminance of 5,000 nits (lifetime; T80) are shown in table 1 below.

TABLE 1

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

The compounds used in the apparatus examples and comparative examples are shown in table 2 below.

TABLE 2

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 below and the second host compound is represented by formula 2 below:

HAr-(L₁-Ar₁)_a---(1)

wherein the content of the first and second substances,

L₁represents a single bond, orSubstituted or unsubstituted (C6-C30) arylene;

Ar₁represents a substituted or unsubstituted (C6-C30) aryl group;

a represents an integer of 1 to 3; and is

When a is 2 or more, each (L)₁-Ar₁) May be the same or different;

wherein the content of the first and second substances,

Represented by the following formula 2-1 or 2-2;

wherein the content of the first and second substances,

X₁to X₂₅Each independently representN or CR_a(ii) a And is

2. The host material of claim 1, wherein formula 1 is represented by the following formula 1-1 or 1-2:

wherein the content of the first and second substances,

Y₁to Y₆And Z₁To Z₄Each independently represents CR₄Or N, provided that Y₁To Y₆Represents N, and Z₁To Z₄Represents N;

R₄each 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;

L₁、Ar₁and a is as defined in claim 1.

3. The host material of claim 1, wherein formula 2 is represented by the following formula 2-1-1:

wherein the content of the first and second substances,

R₄₁to R₄₃Each independently represents hydrogen, tritium, 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 tri (C1-C30) alkylsilyl, substituted or unsubstituted di (C1-C30) alkyl (C6-C30) arylsilyl, substituted or unsubstituted (C1-C30) alkyl di (C6-C30) arylsilyl, substituted or unsubstituted tri (C6-C30) arylsilyl, substituted or unsubstituted mono-or di- (C1-C30) alkylamino, substituted or unsubstituted mono-or di- (C6-C30) arylamino, substituted or unsubstituted mono-C6-C30) arylamino, Or a substituted or unsubstituted (C1-C30) alkyl (C6-C30) arylamino group; or may be linked to an adjacent substituent to form a ring;

4. The host material of claim 1, wherein the formula 2-2 is represented by the following formula 2-2-1:

wherein the content of the first and second substances,

R₃₁to R₃₄Each independently represents hydrogen, tritium, 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 tri-alkyl(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 tri (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 an adjacent substituent to form a ring;

5. The host material according to claim 1, wherein Ar represents a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted orthobiphenyl group, a substituted or unsubstituted metabiphenyl group, a substituted or unsubstituted paraphenylene group, a substituted or unsubstituted naphthylphenyl group, a substituted or unsubstituted phenylnaphthyl group, a substituted or unsubstituted orthoterphenyl group, a substituted or unsubstituted metaterphenylene group, a substituted or unsubstituted paratiphenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzocarbazolyl group, a substituted or unsubstituted dibenzocarbazolyl group, a substituted or unsubstituted dibenzothienyl group, a substituted or unsubstituted benzothienyl group, a substituted or unsubstituted benzonaphthothienyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted benzofuranyl group, a substituted or unsubstituted benzonaphthofuranyl group, a substituted or unsubstituted naphthofuranyl 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 biphenylylamino group, a substituted or unsubstituted biphenylfluorenylamino group, or a substituted or unsubstituted biphenyldibenzofuranylamino group.

6. The host material of claim 1, wherein the compound represented by formula 1 is selected from the group consisting of:

7. the host material of claim 1, wherein the compound represented by formula 2 is selected from the group consisting of:

8. 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 comprises a plurality of host materials according to claim 1.