TWI835817B - A plurality of host materials and organic electroluminescent device comprising the same - Google Patents

Abstract

The present disclosure relates to a plurality of host materials comprising at least one of a first host compound represented by formula 1 and at least one of a second host compound represented by formula 2 and an organic electroluminescent device comprising the same. By comprising the host materials, an organic electroluminescent device having low driving voltage and/or a high luminous efficiency and/or long lifespan can be provided.

Description

Various host materials and organic electroluminescent devices containing the same

The present disclosure relates to a variety of host materials and an organic electroluminescent device comprising the same.

An electroluminescent device (EL device) is a self-luminous display device whose advantages are that it provides a wider viewing angle, a larger 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 the light-emitting layer [Appl. Phys. Lett. [Applied Physics Letters] 51, 913, 1987].

An organic EL device (OLED) converts electrical energy into light by applying electricity 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 auxiliary layer, a light emitting auxiliary layer, an electron blocking layer, a light emitting layer (containing a host material and a dopant material), an electron buffer layer, and a hole Barrier layer, electron transport layer, electron injection layer, etc. Materials used in the organic layer can be divided into hole injection materials, hole transport materials, hole auxiliary materials, luminescence auxiliary materials, electron blocking materials, luminescent materials, electron buffer materials, hole blocking materials, depending on their functions. Electron transport materials, electron injection materials, etc. 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 the holes and 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 from the excited state to the ground state.

The most important factor that determines the luminous efficiency in organic EL devices is the luminescent material. Luminescent materials are required to have the following characteristics: high quantum efficiency, high mobility of electrons and holes, 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 luminescent color, and further include yellow or orange luminescent materials. In addition, in terms of functionality, luminescent materials are divided into host materials and dopant materials. Recently, there is an urgent task to develop organic EL devices with high efficiency and long life. In particular, considering the EL characteristics required for medium- and large-sized OLED panels, there is an urgent need to develop highly superior luminescent materials that are superior to conventional materials. To this end, preferably as a solvent and energy emitter in the solid state, the host material is preferably characterized by high purity and suitable molecular weight for deposition under vacuum. In addition, the host material is required to have high glass transition temperature and pyrolysis temperature for thermal stability, high electrochemical stability for long life, easy formability of amorphous films, good adhesion to adjacent layers, and There is no mobility between layers.

Luminescent materials can be used as a combination of hosts and dopants to improve color purity, luminous efficiency and stability. Generally, a device having excellent EL characteristics has a structure including a light-emitting layer formed by doping a dopant into a host. When using such dopant/host material systems as luminescent materials, their selection is important because the host materials greatly affect the efficiency and lifetime of the EL device.

Korean Patent Publication No. 2018-0012709 A discloses a compound with a fused structure as a host material, and the fused structure includes indolocarbazole and nitrogen diazepam; however, the reference does not specifically disclose a compound with a fused structure as disclosed in the present disclosure. A variety of host materials in specific combinations.

Problems to Be Solved The objectives of the present disclosure are, firstly, to provide a variety of host materials capable of producing organic electroluminescent devices with low driving voltage and/or high luminous efficiency, and/or long life, and secondly, to provide a device containing the same Host material for organic electroluminescent devices. problem solution

As a result of in-depth research to solve the above technical problems, the inventors of the present invention found that the above objectives can be achieved by a plurality of 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-(L ₁ -Ar ₁ ) _a --- (1)

In equation 1,

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

_L1 represents a single bond, or a substituted or unsubstituted (C6-C30)arylene group;

Ar ₁ represents a substituted or unsubstituted (C6-C30) aryl group;

a represents an integer from 1 to 3; and

When a is 2 or greater, each (L ₁ -Ar ₁ ) may be the same or different. --- (2)

In equation 2,

_L2 represents 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 (3-30-membered) heteroarylene group;

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

R ₁₆ to R ₂₀ each independently represent 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

It is represented by the following formula 2-1 or 2-2. --- (2-1) --- (2-2)

In equations 2-1 and 2-2,

X ₁ to X ₂₅ each independently represents N or CR _a ; and

R _a each independently represents hydrogen, deuterium, halogen, cyano group, substituted or unsubstituted (C1-C30) alkyl group, substituted or unsubstituted (C6-C30) aryl group, substituted or unsubstituted (3-membered to 30 members) 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 Substituted tri(C6-C30)arylsilyl, substituted or unsubstituted mono- or di-(C1-C30)alkylamino, substituted or unsubstituted mono- or di-(C6-C30)aryl Amino group, or substituted or unsubstituted (C1-C30)alkyl (C6-C30)arylamino group; or can be connected to an adjacent substituent to form a ring. Invention effect

By using a plurality of 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 life can be prepared.

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 and an organic electroluminescent device comprising the host materials. The plurality of host materials comprises at least one first host compound represented by Formula 1 above and at least one second host compound represented by Formula 2 above.

Herein, "organic electroluminescent material" means a material that can be used in an organic electroluminescent device and that can contain at least one compound. If necessary, the organic electroluminescent material may be included in any layer constituting the organic electroluminescent device. For example, organic electroluminescent materials can be hole injection materials, hole transport materials, hole auxiliary materials, luminescence auxiliary materials, electron blocking materials, luminescent materials (containing host materials and dopant materials), electron buffer materials, electron Hole blocking materials, electron transport materials, or electron injection materials, etc.

Herein, "a plurality of host materials" means a host material including 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 included in the organic electroluminescent device (eg, before vapor deposition) and a material after being included in the organic electroluminescent device (eg, after vapor deposition). By. 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 organic electroluminescent materials. By methods known in the art, at least two compounds included in the various host materials of the present disclosure may be included together in one emitting layer, or may each be included in separate emitting layers. For example, the at least two compounds can be evaporated mixedly or co-evaporated, or evaporated individually.

Herein, "(C1-C30) (extended) alkyl" means a straight or branched alkyl group having 1 to 30 carbon atoms constituting the chain, wherein the number of carbon atoms is preferably 1 to 20, and more preferably 1 to 10. The above alkyl groups may include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tertiary butyl, etc. "(C3-C30) (extended) cycloalkyl" is a monocyclic hydrocarbon or polycyclic hydrocarbon having 3 to 30 carbon atoms in the ring skeleton, wherein the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkyl groups may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc. "(C3-C30)cycloalkenyl" means a monocyclic hydrocarbon or polycyclic hydrocarbon having a ring 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 may include cyclopropenyl, cyclobutenyl, cyclopentenyl, etc. "(3-membered 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 O, S and N, and includes tetrahydrofuran, pyrrolidine, tetrahydrothiophene (thiolan), tetrahydropyran, etc. The "(C6-C30) (lene)aryl group" is a monocyclic or condensed ring group derived from an aromatic hydrocarbon having 6 to 30 ring skeleton carbon atoms, wherein the number of ring skeleton carbon atoms is preferably 6 to 20, more preferably 6 to 15, which may be partially saturated and may contain 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, triphenylenyl, phenylphenanthryl, anthracenyl, benzanthryl, indenyl, triphenylenyl, pyrenyl, naphthacenyl, peryl, chrysenyl, benzochyl, naphthacenyl, fluoranthenyl, benzofluoranthenyl, tolyl, xylyl, mesityl, cumyl, spiro[fluoren-fluoren]yl, spiro[fluoren-benzofluoren]yl, azulenyl and the like. More specifically, the aryl group can be o-tolyl, m-tolyl, p-tolyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl, o-cumyl, m-cumyl, p-cumyl, p-tert-butylphenyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenyl, 4"-tert-butyl-p-terphenyl-4-yl, o-biphenyl, m-biphenyl, p-biphenyl, o-terphenyl, m-tert-phenyl, phenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-quaterphenyl, 1-naphthyl, 2-naphthyl, 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, 9-fluorenyl, 9,9-dimethyl-1-fluorenyl, 9,9-dimethyl-2-fluorenyl, 9,9-dimethyl-3-fluorenyl, 9,9-dimethyl-4- Fluorenyl, 9,9-diphenyl-1-fluorenyl, 9,9-diphenyl-2-fluorenyl, 9,9-diphenyl-3-fluorenyl, 9,9-diphenyl-4-fluorenyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthrenyl, 2-phenanthrenyl, 3-phenanthrenyl, 4-phenanthrenyl, 9-phenanthrenyl, 1-chrysyl, 2-chrysyl, 3-chrysyl, 4-chrysyl, 5-chrysyl, 6-chrysyl, benzo[c]phenanthrenyl, benzo[g]phenanthrenyl, 1-benzophenanthrenyl The term "(3- to 30-membered) heteroaryl" refers to an aryl group having 3 to 30 ring skeleton atoms, wherein the number of ring skeleton atoms is preferably 5 to 25, 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 groups may be monocyclic or condensed rings 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, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (5-30-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)alkylamine, substituted or unsubstituted mono- or di-(C6-C30)arylamine, and substituted or unsubstituted (C1-C30)alkyl(C6-30)arylamine. In addition, the above heteroaryl group may be a heteroaryl group formed by connecting at least one heteroaryl group or aryl group to the heteroaryl group via one or more single bonds; and may contain a spiro structure. Examples of heteroaryl groups specifically include monocyclic heteroaryl groups, including furanyl, thienyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxadiazolyl, triazolyl, tetraazolyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrimidinyl, pyrimidinyl, pyrimidinyl, pyrimidinyl, and the like; and fused ring heteroaryl groups, including benzofuranyl, benzothienyl, isobenzofuranyl, dibenzofuranyl, dibenzothienyl, benzimidazolyl, benzothiophene, benzofuranyl, benzofuranyl, benzothiophene, benzoimidazolyl, benzofuranyl ... , benzothiazolyl, benzoisothiazolyl, benzoisozolyl, benzoxazolyl, imidazopyridinyl, isoindolyl, indolyl, benzindolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, octinyl, quinazolinyl, quinolinyl, carbazolyl, azacarbazolyl, benzocarbazolyl, dibenzocarbazolyl, phenanthridinyl, benzodioxacyclopentyl, indolizidinyl, acryl, silafluorenyl, germaniumfluorenyl and the like. More specifically, the heteroaryl group can be 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidyl, 4-pyrimidyl, 5-pyrimidyl, 6-pyrimidyl, 1,2,3-trioxadiazole, 1,2,4-trioxadiazole, 1,3,5-trioxadiazole, 1-imidazolyl, 2-imidazolyl, 1-pyrazolyl, 1-indolizidin ...,2,3-trioxadiazole, 1,2,4-trioxadiazole, 1-indolizidinyl, 1-indolizidinyl, 1-indolizidinyl, 1-indolizidinyl, 1-indolizidinyl, 1,2,3-trioxadiazole, 1,2,4-trioxadiazole, 1 idinyl), 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-benzofuranyl, 3-benzofuranyl, 4-benzofuranyl, 5-benzofuranyl, 6-benzofuranyl, 7-benzofuranyl, 1-isobenzofuranyl, 3-isobenzofuranyl, 4-isobenzofuranyl furanyl, 5-isobenzofuranyl, 6-isobenzofuranyl, 7-isobenzofuranyl, 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-quinolyl, 5-quinolyl, 6-quinolyl, 1- carbazolyl, 2-carbazolyl, 3-carbazolyl, 4-carbazolyl, 9-carbazolyl, nitrogen-doped carbazole-1-yl, nitrogen-doped carbazole-2-yl, nitrogen-doped carbazole-3-yl, nitrogen-doped carbazole-4-yl, nitrogen-doped carbazole-5-yl, nitrogen-doped carbazole-6-yl, nitrogen-doped carbazole-7-yl, nitrogen-doped carbazole-8-yl, nitrogen-doped carbazole-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-thienyl -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-germaniumfluorenyl, 2-germaniumfluorenyl, 3-germaniumfluorenyl, 4-germaniumfluorenyl, etc. Herein, "halogen" includes F, Cl, Br, and I.

In addition, "ortho (o)", "meta (m)", and "para (p)" are meant to represent the substitution positions of all substituents. Ortho positions are compounds having substituents adjacent to each other, for example at the 1 and 2 positions of benzene. The meta position is the substitution position immediately next to the substitution position, for example, a compound has substituents at positions 1 and 3 on benzene. The para position is the next substitution position for the meta position, for example, a compound has substituents at positions 1 and 4 on benzene.

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

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, L ₁ , Ar ₁ , L ₂ , Ar, R ₁₆ to R ₂₀ , and R _a in formulas 1 and 2, substituted (C1-C30)(alkylene)alkyl, substituted (C6-C30) (Extended) aryl, substituted (3- to 30-membered) hetero(extended) aryl, substituted (C3-C30) (extension) cycloalkyl, substituted (C3-C30) cycloalkenyl, substituted ( 3 to 7 members) heterocycloalkyl, substituted (C1-C30) alkoxy, substituted tris (C1-C30) alkylsilyl, substituted di(C1-C30) alkyl (C6-C30) Arylsilyl, substituted (C1-C30)alkyl di(C6-C30)arylsilyl, substituted tri(C6-C30)arylsilyl, substituted mono- or di-(C1-C30) Substituents for alkylamino, substituted mono- or di-(C6-C30)arylamino, and substituted (C1-C30)alkyl(C6-C30)arylamino are each independently selected from At least one of the following, the group consisting of: deuterium, halogen, cyano, carboxyl, nitro, hydroxyl, (C1-C30) alkyl, halogenated (C1-C30) alkyl, (C2-C30 )alkenyl, (C2-C30)alkynyl, (C1-C30)alkoxy, (C1-C30)alkylthio, (C3-C30)cycloalkyl, (C3-C30)cycloalkenyl, (3 (members to 7 members) heterocycloalkyl, (C6-C30) aryloxy, (C6-C30) arylthio, (C6-C30) aryl-substituted or unsubstituted (5 to 30 members) heteroaryl base, (5 to 30 members) heteroaryl-substituted or unsubstituted (C6-C30) aryl, tris (C1-C30) alkyl silyl, tris (C6-C30) aryl silyl, di( C1-C30)alkyl (C6-C30)arylsilyl, (C1-C30)alkyldi(C6-C30)arylsilyl, amine, mono- or di-(C1-C30)alkylamine base, (C1-C30)alkyl-substituted or unsubstituted mono- or di-(C6-C30)arylamino group, (C1-C30)alkyl (C6-C30)arylamino group, (C1- C30)alkylcarbonyl, (C1-C30)alkoxycarbonyl, (C6-C30)arylcarbonyl, di(C6-C30)arylboroncarbonyl, di(C1-C30)alkylboroncarbonyl, (C1- C30)alkyl(C6-C30)arylboroncarbonyl, (C6-C30)aryl(C1-C30)alkyl, and (C1-C30)alkyl(C6-C30)aryl, for example, the substituents may It is a substituted or unsubstituted methyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted fluoryl group, a substituted or unsubstituted carbazolyl group , a substituted or unsubstituted dibenzofuryl group, a substituted or unsubstituted dibenzothienyl group, a substituted or unsubstituted diphenylamine group, or a substituted or unsubstituted phenylbiphenylamine group.

Hereinafter, the main body material according to one implementation method will be described.

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

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

HAr-(L ₁ -Ar ₁ ) _a --- (1)

In equation 1,

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

_L1 represents a single bond, or a substituted or unsubstituted (C6-C30)arylene group;

Ar ₁ represents a substituted or unsubstituted (C6-C30) aryl group;

a represents an integer from 1 to 3; and

When a is 2 or greater, each (L ₁ -Ar ₁ ) may be the same or different.

In one embodiment, HAr can be a substituted or unsubstituted nitrogen-containing (5- to 10-membered) heteroaryl group, preferably an unsubstituted nitrogen-containing (6- to 10-membered) heteroaryl group. For example, HAr can be pyrimidinyl, trioxyl, quinolinyl, quintilinyl, or quinazolinyl.

In one embodiment, _L1 can be a single bond, or a substituted or unsubstituted (C6-C25)arylene, preferably a single bond or unsubstituted (C6-C20)arylene. For example, _L1 can be a single bond, naphthyl- or fluorenyl-substituted or unsubstituted phenylene, m-biphenylene, p-biphenylene, naphthylene, phenyl-substituted or unsubstituted fluorenylene, or phenyl-substituted or unsubstituted benzofluorenylene.

In one embodiment, Ar ₁ can be substituted or unsubstituted (C6-C25)aryl, preferably (C1-C6)alkyl- or (C6-C18)aryl-substituted or unsubstituted ( C6-C18) aryl. For example, Ar ₁ can be fluorenyl-substituted or unsubstituted phenyl, m-biphenyl, p-biphenyl, naphthyl, m-terphenyl, p-terphenyl, benzophenanthyl, phenanthrenyl, at least one phenyl - or at least one methyl-substituted benzoyl (e.g., phenylbenzoyl, diphenylbenzoyl, or dimethylbenzoyl), or at least one phenyl- or at least one methyl-substituted benzoyl Benzyl (e.g., dimethylbenzobenzoyl or diphenylbenzobenzoyl).

In one embodiment, a may be an integer of 2 or 3, wherein each (L ₁ -Ar ₁ ) may be the same or different.

The compound represented by Formula 1 may be represented by the following Formula 1-1 or 1-2. --- (1-1) --- (1-2)

In equations 1-1 and 1-2,

_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;

_R4 each independently represents hydrogen, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C2-C30) alkenyl, or substituted or unsubstituted (C6-C30) aryl; or may be linked to an adjacent substituent to form a ring; and

L ₁ , Ar ₁ , and a are as defined in Formula 1.

In one embodiment, in Formula 1-1, at least one of _Y1 to _Y6 may be N, preferably, at least two of _Y1 to _Y6 may be N, and more preferably, at least three of _Y1 to _Y6 may be N. For example, the compound represented by Formula 1-1 may be (L ₁ -Ar ₁ ) _a -substituted pyrimidine or triazine.

In one embodiment, in Formula 1-2, at least one of _Z1 to _Z4 may be N, and preferably, at least two of _Z1 to _Z4 may be N. For example, the compound represented by Formula 1-2 may be ( _L1 - _Ar1 ) _a -substituted quinoline, quinoline, or quinazoline.

In one embodiment, _R4 independently represents hydrogen, substituted or unsubstituted (C1-C20) alkyl, substituted or unsubstituted (C2-C20) alkenyl, or substituted or unsubstituted (C6-C18) aryl; or two adjacent _R4 can be connected to each other to form a substituted or unsubstituted (3-30) monocyclic or polycyclic ring, preferably, hydrogen or two adjacent _R4 can be connected to each other to form an unsubstituted (3-18) monocyclic or polycyclic ring, more preferably, hydrogen or two adjacent _R4 can be connected to each other to form an unsubstituted (3-10) monocyclic ring. For example, _R4 independently represents hydrogen or two adjacent _R4 can be fused to each other to form an unsubstituted benzene ring.

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

The compound of formula 1 according to the present disclosure can be produced by a synthetic method known to those skilled in the art. For example, the compound represented by formula 1-1 or 1-2 can be synthesized with reference to the following reaction scheme 1 or 2, but is not limited thereto: [ Reaction Scheme 1] [ Reaction Scheme 2]

In Reaction Schemes 1 and 2, L ₁ , Ar ₁ and a are as defined in Formula 1, and Y ₁ to Y ₆ and Z ₁ to Z ₄ are as defined in Formulas 1-1 and 1-2.

As described above, exemplary synthesis examples of the compound 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, 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, cyclodehydration reaction, SN ₁ substitution reaction, SN ₂ substitution reaction, phosphine-mediated reductive cyclization reaction, etc. It will be understood by those skilled in the art that the above reaction 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.

According to one embodiment, the second host compound as another host material may be represented by Formula 2 below. --- (2)

In formula 2,

L ₂ represents a single bond, a substituted or unsubstituted (C1-C30) alkylene group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3 to 30 members) heteroaryl group , or substituted or unsubstituted (C3-C30) cycloalkyl;

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

R ₁₆ to R ₂₀ each independently represent 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 It is represented by the following formula 2-1 or 2-2. --- (2-1) --- (2-2)

In formulas 2-1 and 2-2,

X ₁ to X ₂₅ each independently represents N or CR _a ; and

_Ra 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 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)alkylamine, substituted or unsubstituted mono- or di-(C6-C30)arylamine, or substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamine; or may be linked to an adjacent substituent to form a ring.

In one embodiment, L ₂ can be a single bond, a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (3- to 30-membered) heteroaryl group, preferably a single bond , substituted or unsubstituted (C6-C25) aryl group, or substituted or unsubstituted (5 to 25 members) heteroaryl group, more preferably single bond, substituted or unsubstituted (C6-C18) Aryl group, or substituted or unsubstituted (5 to 18 members) heteroaryl group. For example, L ₂ can be a single bond, or a substituted or unsubstituted phenylene group, a substituted or unsubstituted ortho-biphenyl group, a substituted or unsubstituted meta-biphenyl group, or a substituted or unsubstituted p-biphenyl group. group, a substituted or unsubstituted naphthylene group, or a substituted or unsubstituted carbazolyl group.

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

Specifically, Ar can be substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted o-biphenyl, substituted or unsubstituted m-biphenyl, substituted or unsubstituted p-biphenyl, substituted or unsubstituted naphthylphenyl, substituted or unsubstituted phenylnaphthyl, substituted or unsubstituted o-terphenyl, substituted or unsubstituted m-terphenyl, substituted or unsubstituted p-terphenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted benzocarbazolyl, substituted or unsubstituted dibenzocarbazolyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted benzothiophenyl, substituted or unsubstituted benzonaphthothiophenyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted benzonaphthofuranyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted benzofluorenyl, substituted or unsubstituted spirobifluorenyl, substituted or unsubstituted diphenylamino, substituted or unsubstituted benzo Ar can be substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted naphthylbiphenylamine, substituted or unsubstituted diphenylamine, substituted or unsubstituted biphenylfluorenylamine, or substituted or unsubstituted biphenyldibenzofuranylamine. For example, Ar can be substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted o-biphenyl, substituted or unsubstituted m-biphenyl, substituted or unsubstituted p-biphenyl, substituted or unsubstituted unsubstituted o-terphenyl, substituted or unsubstituted m-terphenyl, substituted or unsubstituted p-terphenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted benzofluorenyl, substituted or unsubstituted spirobifluorenyl, substituted or unsubstituted diphenylamine, substituted or unsubstituted phenylbiphenylamine, or substituted or unsubstituted naphthylphenylamine.

According to one implementation, in Formula 2, It can be represented by the following formula 2-1. --- (2-1)

In equation 2-1,

_X1 to _X12 each independently represent N or CR _a ; and

R _a each independently represents hydrogen, deuterium, halogen, cyano group, substituted or unsubstituted (C1-C30) alkyl group, substituted or unsubstituted (C6-C30) aryl group, substituted or unsubstituted (3-membered to 30 members) 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 Substituted tri(C6-C30)arylsilyl, substituted or unsubstituted mono- or di-(C1-C30)alkylamino, substituted or unsubstituted mono- or di-(C6-C30)aryl Amino group, or substituted or unsubstituted (C1-C30)alkyl (C6-C30)arylamino group; or can be connected to an adjacent substituent to form a ring.

In one embodiment, R _a can each independently be hydrogen, deuterium, or a substituted or unsubstituted (C6-C30) aryl group; or can be connected to an adjacent substituent to form a ring, preferably hydrogen, Deuterium, or substituted or unsubstituted (C6-C25) aryl; or can be connected or fused to adjacent substituents to form a substituted or unsubstituted (3 to 30 members) monocyclic or polycyclic alicyclic ring Acyclic rings, aromatic rings, or combinations thereof, more preferably hydrogen, deuterium, or substituted or unsubstituted (C6-C18) aryl groups; or can be connected or fused to adjacent substituents to form substituted or Unsubstituted (5 to 30 members) monocyclic or polycyclic aromatic rings, or combinations thereof. For example, R _a can each independently be hydrogen or substituted or unsubstituted phenyl; or can be fused to each other to form a substituted or unsubstituted aromatic ring.

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.

Specifically, according to one implementation, Formula 2-1 can be expressed by Formula 2-1-1. --- (2-1-1)

In formula 2-1-1,

R ₄₁ to R ₄₃ each independently represent hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3-30-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)alkylamine, substituted or unsubstituted mono- or di-(C6-C30)arylamine, or substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamine; or may be linked to an adjacent substituent to form a ring;

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

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.

In one embodiment, R ₄₁ to R ₄₃ may each independently be hydrogen, deuterium, or substituted or unsubstituted (C6-C30)aryl; or may be connected to an adjacent substituent to form a ring, preferably hydrogen, deuterium, or substituted or unsubstituted (C6-C25)aryl; 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 substituted or unsubstituted (C6-C18)aryl; 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 ₄₁ to R ₄₃ may each independently be hydrogen or a substituted or unsubstituted phenyl group; or may be condensed with each other to form a substituted or unsubstituted aromatic ring.

According to another embodiment, in Formula 2, It can be represented by the following formula 2-2. --- (2-2)

In formula 2-2,

X ₁₃ to X ₂₅ each independently represents N or CR _a ; and

_Ra 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 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)alkylamine, substituted or unsubstituted mono- or di-(C6-C30)arylamine, or substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamine; or may be linked to an adjacent substituent to form a ring.

In one embodiment, R _a can each independently be hydrogen, deuterium, or a substituted or unsubstituted (C6-C30) aryl group; or can be connected to an adjacent substituent to form a ring, preferably hydrogen, Deuterium, or substituted or unsubstituted (C6-C25) aryl; or can be connected or fused to adjacent substituents to form a substituted or unsubstituted (3 to 30 members) monocyclic or polycyclic alicyclic ring Acyclic rings, aromatic rings, or combinations thereof, more preferably hydrogen, deuterium, or substituted or unsubstituted (C6-C18) aryl groups; or can be connected or fused to adjacent substituents to form substituted or Unsubstituted (5 to 30 members) monocyclic or polycyclic aromatic rings, or combinations thereof. For example, R _a can each independently be hydrogen or substituted or unsubstituted phenyl; or can be fused to each other to form a substituted or unsubstituted aromatic ring.

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.

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.

Specifically, according to one implementation, Formula 2-2 can be expressed by Formula 2-2-1. --- (2-2-1)

In formula 2-2-1,

_R31 to _R34 each independently represent hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3-30-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)alkylamine, substituted or unsubstituted mono- or di-(C6-C30)arylamine, or substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamine; 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, ad represents an integer from 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 may be the same or different.

In one embodiment, R ₃₁ to R ₃₄ may each independently be hydrogen, deuterium, or substituted or unsubstituted (C6-C30)aryl; or may be linked to an adjacent substituent to form a ring, preferably hydrogen, deuterium, or substituted or unsubstituted (C6-C25)aryl; 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 substituted or unsubstituted (C6-C18)aryl; 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 represents hydrogen or a substituted or unsubstituted phenyl group; or may be condensed with each other to form a substituted or unsubstituted aromatic ring.

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:

According to the compound of formula 2 disclosed herein, 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.

Hereinafter, organic electroluminescent devices applying the above-described various host materials will be described.

The organic electroluminescent device according to the present disclosure includes a first electrode, a second electrode, and at least one organic layer inserted between the first electrode and the second electrode. The organic layer may include a light-emitting layer, and the light-emitting layer may include a host material, wherein the host materials include 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 included in the same organic layer or may be respectively included in different organic layers.

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 preferred 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. The first electrode and the second electrode may each be formed as a transmissive conductive material, a semi-transmissive reflective conductive material, or a reflective conductive material. Depending on the type of material forming the first electrode and the second electrode, the organic electroluminescent device may be a top-emitting type, a bottom-emitting type, or a two-sided emitting type. The organic layer may include a light-emitting layer, and may further include at least one layer selected from the following items: a hole injection layer, a hole transport layer, a hole auxiliary layer, a light-emitting auxiliary 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 azide-based compound in addition to the luminescent material according to the present disclosure. Specifically, the hole injection layer, the hole transport layer, the hole auxiliary layer, the luminescent layer, the luminescent auxiliary 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 auxiliary material, a luminescent material, a luminescent auxiliary 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 acryl-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 a metal of Group 1 of the periodic table, a metal of Group 2, a transition metal of period 4, a transition metal of period 5, lanthanum Organometallic elements of series elements and d-transition elements, or at least one complex compound containing such metals.

According to one embodiment, an organic electroluminescent material may be used as a light-emitting material for a white organic light-emitting device. According to the arrangement of R (red), G (green), B (blue), or YG (yellow-green) light-emitting units, white organic light-emitting devices have demonstrated various structures, such as a parallel side-by-side arrangement method, a stacked arrangement method, or CCM ( Color conversion materials) methods, etc. In addition, according to one embodiment, the organic electroluminescent material can 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 multi-layer to reduce the hole injection potential (or hole injection voltage) from the anode to the hole transport layer or the electron blocking layer, wherein each of the multi-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 placed between the hole transport layer (or hole injection layer) and the light-emitting layer, and may confine excitons within the light-emitting layer by blocking electrons from overflowing from the light-emitting layer to prevent light leakage. The hole transport layer or the electron blocking layer may be a plurality of layers, 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 can be multiple layers to control the injection of electrons and improve the interface characteristics between the light-emitting layer and the electron injection layer, wherein each multi-layer can use two compounds at the same time. The hole blocking layer or electron transport layer can also be multiple layers, where multiple compounds can be used for each layer. In addition, the electron injection layer may be doped with n-type dopants.

The luminescence auxiliary layer can be placed between the anode and the luminescent layer, or between the cathode and the luminescent layer. When the luminescence auxiliary layer is placed between the anode and the luminescent layer, it can be used to promote hole injection and/or hole transport, or to prevent electron overflow. When the luminescence auxiliary layer is placed between the cathode and the luminescent layer, it can be used to promote electron injection and/or electron transport, or to prevent hole overflow. In addition, the hole auxiliary layer can be placed between the hole transport layer (or hole injection layer) and the luminescent layer, and can effectively promote or block the hole transport rate (or hole injection rate), thereby enabling the control of charge balance. When the organic electroluminescent device includes two or more hole transport layers, the further included hole transport layer can be used as a hole auxiliary layer or an electron blocking layer. The luminescence auxiliary layer, the hole auxiliary layer, or the electron blocking layer can have the effect of improving the efficiency and/or life of the organic electroluminescent device.

In the organic electroluminescent device of the present disclosure, it may be preferable that at least one layer selected from the group consisting of a chalcogenide layer, a metal halide layer and a metal oxide layer (hereinafter, "surface layer") is disposed on one or on one or more inner surfaces of both electrodes. Specifically, it is preferable to place a chalcogenide (including oxide) layer of silicon and aluminum on the anode surface of the electroluminescent medium layer, and it is preferable to place a halide metal layer or a metal oxide layer on the electroluminescent medium layer. on the cathode surface of the electroluminescent dielectric layer. The operational stability of organic electroluminescent devices can be obtained through the surface layer. _{Preferably ,} chalcogenides _{include SiO} ; And metal oxides include Cs ₂ O, Li ₂ O, MgO, SrO, BaO, CaO, etc.

In addition, in the organic electroluminescent device disclosed in the present invention, 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 can be placed on at least one surface of a pair of electrodes. In this case, the electron transport compound is reduced to anions, 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 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, alkali earth metals, rare earth metals, and mixtures thereof. In addition, the reducing dopant layer can be used as a charge generating 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 contained in the organic electroluminescent material of the present disclosure may be at least one phosphorescent dopant or a fluorescent dopant, preferably a phosphorescent dopant. The phosphorescent dopant material used in the organic electroluminescent device of the present disclosure is not particularly limited, but may preferably be one or more metalized complex compounds of one or more metal atoms selected from the following: iridium (Ir), benzium (Os), copper (Cu), and platinum (Pt), more preferably one or more vicinal metalized complex compounds of one or more metal atoms selected from the following: iridium (Ir), benzium (Os), copper (Cu), and platinum (Pt), and even more preferably one or more vicinal metalized iridium complex compounds.

The dopant included in the organic electroluminescence device may use a compound represented by the following formula 101, but is not limited thereto: --- (101)

In Equation 101,

Where, L is selected from the following structures 1 or 2: --- Structure(1) --- Structure(2)

_R100 to _R103 each independently represent 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 (3-30-membered)heteroaryl, or substituted or unsubstituted (C1-C30)alkoxy; or _R100 to _R103 may be linked to one or more adjacent substituents to form a substituted or unsubstituted fused ring, for example, substituted or unsubstituted quinoline, substituted or unsubstituted benzofuranopyridine, substituted or unsubstituted benzothienopyridine, substituted or unsubstituted indenopyridine, substituted or unsubstituted benzofuranoquinoline, substituted or unsubstituted benzothienoquinoline, or substituted or unsubstituted indenoquinoline;

R ₁₀₄ to R ₁₀₇ 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, substituted or unsubstituted (3 to 30 members) heteroaryl, cyano, or substituted or unsubstituted (C1-C30) alkoxy; or R ₁₀₄ to R ₁₀₇ can be connected to on one or more adjacent substituents to form a substituted or unsubstituted fused ring, for example, substituted or unsubstituted naphthyl, substituted or unsubstituted fluorine, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofurans, substituted or unsubstituted indenopyridines, substituted or unsubstituted benzofuropyridines, or substituted or unsubstituted benzothienopyridines;

R ₁₁₁ to R ₁₂₁ each independently represents hydrogen, deuterium, halogen, 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

s represents an integer from 1 to 3.

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

In order 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. When a wet film-forming method is used, the film can be formed by dissolving or diffusing the materials forming each layer into any suitable solvent such as ethanol, chloroform, tetrahydrofuran, dihydrofuran, etc. The solvent may be any solvent in which the material forming each layer can be dissolved or diffused and has no problem in film-forming ability.

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

Co-deposition is a mixed deposition method in which two or more isomeric materials are placed in corresponding single crucible sources and current is applied to two chambers at the same time to evaporate the materials and perform mixed deposition; and mixed deposition is a mixed deposition method in which two or more isomeric materials are mixed in one crucible source before depositing them and then current is applied to one chamber to evaporate the materials.

According to one embodiment, the organic electroluminescent device of the present disclosure can be used to manufacture display devices such as smartphones, tablets, laptops, PCs, TVs, or display devices for vehicles, or lighting devices such as outdoor Or indoor lighting.

Hereinafter, the preparation method of the organic electroluminescent device including multiple host materials according to the present disclosure and its characteristics will be explained in order to understand the present disclosure in detail. [ Device Examples 1 to 8] Production of an OLED in which the first host compound and the second compound according to the present disclosure are deposited as the host

OLED devices containing compounds of the present disclosure are produced. First, a transparent electrode indium tin oxide (ITO) film (10 Ω/sq) (GEOMATEC CO., LTD., Japan) used on a glass substrate for an OLED device was subjected to sequential cleaning with acetone, ethanol, and distilled water. Ultrasonically washed, and then stored in isopropyl alcohol. The ITO substrate is then mounted on the substrate holder of the vacuum vapor deposition equipment. Compound HI-1 was introduced into the chamber of the vacuum vapor deposition apparatus, and the pressure in the chamber of the apparatus was then controlled to 10 ^-6 Torr. Thereafter, a current was applied to the small chamber to evaporate the material introduced above, thereby forming a first hole injection layer with a thickness of 80 nm on the ITO substrate. Next, compound HI-2 was introduced into another chamber of the vacuum vapor deposition equipment, and the compound was evaporated by applying a current to the chamber, thereby forming a second hole injection layer with a thickness of 5 nm on the first hole injection layer. hole injection layer. The compound HT-1 was then introduced into another chamber of the vacuum vapor deposition equipment, and the compound was evaporated by applying a current to the chamber, thereby forming a first hole transport with a thickness of 10 nm on the second hole injection layer. layer. The compound HT-2 is then introduced into another chamber of the vacuum vapor deposition equipment, and the compound is evaporated by applying a current to the chamber, thereby forming a second hole transport layer with a thickness of 60 nm on the first hole transport layer layer. After the hole injection layer and the hole transport layer are formed, 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 a small chamber of the vacuum vapor deposition equipment, and Compound RD-39 was introduced into another chamber as a dopant. The two host materials were evaporated at different rates and dopants were deposited at a doping amount of 3 wt% to form a light-emitting layer with a thickness of 40 nm on the hole transport layer. Next, compounds ET-1 and EI-1 were evaporated and deposited at a rate of 1:1 to form an electron transport layer with a thickness of 35 nm on the light-emitting layer. After depositing compound EI-1 on the electron transport layer as an electron injection layer with a thickness of 2 nm, another vacuum vapor deposition equipment was used to deposit an Al cathode with a thickness of 80 nm on the electron injection layer. From this, OLED was produced. [ Comparative Examples 1 and 2] Production of OLEDs containing 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 respectively used as hosts.

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

Referring to Table 1 above, it is confirmed that an organic electroluminescent device including a specific combination compound according to one embodiment as a host material has improved characteristics over conventional organic electroluminescent devices in terms of driving voltage and efficiency and/or life.

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

without

without

without

Claims (7)

A composition comprising 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 the following formula 1-1 or 1-2 and the second host compound is represented by the following formula 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; _R4 each independently represents hydrogen or may be linked to an adjacent substituent to form a ring; _L1 represents a single bond, or a substituted or unsubstituted (C6-C30)aryl group; Ar ₁ represents a substituted or unsubstituted (C6-C30) aryl group, wherein the (C6-C30) aryl group is selected from the group consisting of phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, dimethylfluorenyl, benzofluorenyl, diphenylbenzofluorenyl, dibenzofluorenyl, phenanthrenyl, triphenylenyl, phenylphenanthrenyl, anthracenyl, benzanthryl, indenyl, pyrenyl, tetracenyl (tetracenyl/naphthacenyl), peryl,

Chrysenyl, benzo

the group consisting of 1-Ar, 2-Ar, 3-Ar, 4-Ar, 5-Ar, 6-Ar, 7-Ar, 8-Ar, 9-Ar, 10-Ar, 11-Ar, 12-Ar, 13-Ar, 14-Ar, 15-Ar, 16-Ar, 17-Ar, ₁₈ -Ar, 19-Ar, 20-Ar, 21-24-Ar, 22-26-Ar, 27-28-Ar, 29-29-Ar, _{30-31-31-32-33-34-36-37-38} ...

wherein _L2 represents 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, 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, _-NR16R17 , or _-SiR18R19R20 or may be linked to an adjacent substituent to form a ring; R ₁₆ to R ₂₀ each independently represent a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (3-30-membered) heteroaryl group; and

It is represented by the following formula 2-1 or 2-2;

wherein _X1 to _X25 each independently represent N or CR _a ; and 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 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) an arylamine group, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamine group; or may be linked to an adjacent substituent to form a ring. The composition described in item 1 of the patent application, wherein the formula 2 is represented by the following formula 2-1-1:

Wherein, R ₄₁ to R ₄₃ each independently represents hydrogen, deuterium, halogen, cyano group, substituted or unsubstituted (C1-C30) alkyl group, substituted or unsubstituted (C6-C30) aryl group, substituted or unsubstituted (3 to 30 members) 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 group, substituted or unsubstituted tri(C6-C30)arylsilyl group, substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, substituted or unsubstituted mono- or di-(C6 -C30)arylamino, or substituted or unsubstituted (C1-C30)alkyl (C6-C30)arylamino; or can be connected to adjacent substituents to form a ring; ba represents 1 to 3 The integer, bb represents an integer from 1 to 4, and bc represents an integer from 1 to 5; and when ba, bb, and bc are 2 or more, each R ₄₁ , each R ₄₂ or each R ₄₃ may be Same or different. The composition described in item 1 of the patent application, wherein the formula 2-2 is represented by the following formula 2-2-1:

Wherein, R ₃₁ to R ₃₄ each independently represents hydrogen, deuterium, halogen, cyano group, substituted or unsubstituted (C1-C30) alkyl group, substituted or unsubstituted (C6-C30) aryl group, substituted or unsubstituted (3 to 30 members) 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 group, substituted or unsubstituted tri(C6-C30)arylsilyl group, substituted or unsubstituted mono- or di-(C1-C30)alkylamino group, substituted or unsubstituted mono- or di-(C6 -C30)arylamino, or substituted or unsubstituted (C1-C30)alkyl (C6-C30)arylamino; or can be connected to adjacent substituents to form a ring; aa represents 1 to 3 Integers, ab and ac each independently represent an integer from 1 to 4, ad represents an integer of 1 or 2; and when aa, ab, ac, and ad are 2 or more, each R ₃₁ , each R ₃₂ , Each R ₃₃ and each R ₃₄ may be the same or different. The composition as described in item 1 of the patent application, wherein Ar represents a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted o-biphenyl group, a substituted or unsubstituted interlinked Phenyl, substituted or unsubstituted p-biphenyl, substituted or unsubstituted naphthylphenyl, substituted or unsubstituted phenylnaphthyl, substituted or unsubstituted o-terphenyl, substituted or unsubstituted m-terphenyl group, substituted or unsubstituted p-terphenyl group, substituted or unsubstituted carbazolyl group, substituted or unsubstituted benzocarbazolyl group, substituted or unsubstituted dibenzocarbazolyl group, substituted or unsubstituted dibenzocarbazolyl group Benzothienyl, substituted or unsubstituted benzo Thienyl, substituted or unsubstituted benzonaphthienyl, substituted or unsubstituted dibenzofuryl, substituted or unsubstituted benzofuryl, substituted or unsubstituted benzonaphthofuryl, substituted or Unsubstituted fluorenyl group, substituted or unsubstituted benzofenyl group, substituted or unsubstituted spirobibenzyl group, substituted or unsubstituted diphenylamine group, substituted or unsubstituted phenylbiphenylamine group, Substituted or unsubstituted naphthylphenylamino group, substituted or unsubstituted naphthylbiphenylamine group, substituted or unsubstituted diphenylamino group, substituted or unsubstituted biphenylbenzylamino group, Or a substituted or unsubstituted biphenyldibenzofurylamine group. The composition described in item 1 of the patent application, wherein the compound represented by formula 1-1 or 1-2 is selected from the group consisting of the following:

as well as

. The composition as described in claim 1, wherein the compound represented by formula 2 is selected from the group consisting of:

as well as

. An organic electroluminescent device, the organic electroluminescent device includes: an anode, a cathode, and at least one luminescent layer between the anode and the cathode, wherein the at least one luminescent layer includes as described in item 1 of the patent scope It consists of a variety of main materials.