Patent Application
20250194417
The present disclosure relates to an organic electroluminescent device comprising a deuterated compound(s).
A small molecular green organic electroluminescent device (OLED) was first developed by Tang et al. of Eastman Kodak in 1987, utilizing a TPD/ALq3 bi-layer consisting of a light-emitting layer and a charge transport layer. Thereafter, OLED development progressed rapidly, leading to commercialization. Currently, OLEDs primarily use phosphorescent materials with excellent luminous efficiency in panel implementation. However, in various applications such as TVs and lighting, the lifetime of OLEDs is often insufficient, and there is still a need for higher OLED efficiency. Generally, the lifetime of an OLED decreases as its luminance increases. Thus, OLEDs with high luminous efficiency and/or extended lifetime are essential for long-term use and high-resolution displays.
In order to improve current efficiency and/or lifetime, various materials or concepts for an organic layer of an organic electroluminescent device have been proposed, but they have not proved satisfactory in practical use. In addition, there is a continuous demand for the development of an organic electroluminescent device with enhanced performance, such as improved current efficiency and/or lifetime properties, as compared to combinations of previously disclosed specific compounds.
Meanwhile, Korean Patent Application Laid-Open Nos. 2023-0046493, 2022-0081251, and 2022-0147537 disclose an organic electroluminescent device comprising a deuterated compound(s). Nevertheless, the aforementioned references fail to specifically disclose an organic electroluminescent device having overall device stability by comprising a deuterated compound(s) in the electron transport zone. In addition, there is a continuous demand for the development of light-emitting materials with enhanced performance, such as improved lifetime properties, compared to previously disclosed specific organic electroluminescent devices.
The objective of the present disclosure is to provide an organic electroluminescent device with improved current efficiency and/or lifetime properties compared to conventional organic electroluminescent devices.
As a result of intensive study to solve the technical problems, the present inventors found that the above objective can be achieved by an organic electroluminescent device comprising an anode, a hole transport zone, a light-emitting layer, an electron transport zone, and a cathode, wherein the hole transport zone, the light-emitting layer, and the electron transport zone each comprise a deuterated compound(s), and the structures of each of the compounds are the same as or different from each other.
An organic electroluminescent device of the present disclosure exhibits higher current efficiency and/or improved lifetime properties by comprising a deuterated compound(s) in each of the hole transport zone, the light-emitting layer, and the electron transport zone.
Hereinafter, the present disclosure will be described in detail. However, the following description is intended to explain the present disclosure, and is not meant to restrict the scope of the present disclosure.
The term “organic electroluminescent compound” in the present disclosure refers to a compound that may be used in an organic electroluminescent device, and may be incorporated into any layer constituting an organic electroluminescent device, as necessary.
The term “organic electroluminescent material” in the present disclosure refers to a material that may be used in an organic electroluminescent device, and may comprise at least one compound. The organic electroluminescent material may be incorporated into any layer constituting an organic electroluminescent device, as necessary. For example, the organic electroluminescent material may be any of the following: a hole injection material, a hole transport material, a hole auxiliary material, a light-emitting auxiliary material, an electron-blocking material, a light-emitting material (including a host material and a dopant material), an electron buffer material, a hole-blocking material, an electron transport material, an electron injection material, etc.
The term “a plurality of organic electroluminescent materials” in the present disclosure refers to an organic electroluminescent material(s) comprising a combination of two or more compounds, which may be incorporated into any layer constituting an organic electroluminescent device. It may mean both a material before being comprised in an organic electroluminescent device (for example, before vapor deposition) and a material after being comprised in an organic electroluminescent device (for example, after vapor deposition). For example, a plurality of organic electroluminescent materials may be a combination of two or more compounds that may be comprised in at least one layer of 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, an electron buffer layer, a hole-blocking layer, an electron transport layer, and an electron injection layer. The two or more compounds may be comprised in the same layer or different layers, and may be mixture-evaporated or co-evaporated, or may be individually evaporated.
The term “a plurality of host materials” in the present disclosure means a host material comprising a combination of at least two compounds, which may be comprised in any light-emitting layer constituting an organic electroluminescent device. It may mean both a material before being comprised in an organic electroluminescent device (for example, before vapor deposition) and a material after being comprised in an organic electroluminescent device (for example, after vapor deposition). For example, the plurality of host materials of the present disclosure is a combination of at least two host materials, and may selectively further comprise conventional materials comprised in an organic electroluminescent material. At least two compounds comprised in the plurality of host materials of the present disclosure may be comprised together in one light-emitting layer or may respectively be comprised in different light-emitting layers. For example, the at least two host materials may be mixture-evaporated or co-evaporated, or may be individually evaporated.
Herein, the term “(C1-C30)alkyl” is meant to be a linear or branched alkyl having 1 to 30 carbon atoms constituting the chain, in which the number of carbon atoms is preferably 1 to 10, and more preferably 1 to 6. The above alkyl may include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, etc. The term “(C3-C30)cycloalkyl” is meant to be a mono- or polycyclic hydrocarbon having 3 to 30 ring backbone carbon atoms, in which the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkyl may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclohexylmethyl, etc. The term “(3- to 7-membered) heterocycloalkyl” is meant to be a cycloalkyl having 3 to 7 ring backbone atoms, and including at least one heteroatom selected from the group consisting of B, N, O, S, Si, and P, and preferably from the group consisting of O, S, and N. The above heterocycloalkyl may include tetrahydrofuran, pyrrolidine, thiolan, tetrahydropyran, etc. The term “(C6-C30)aryl”, “(C6-C30)arylene”, and “(C6-C30)arentriyl” are meant to be a monocyclic or fused ring radical derived from an aromatic hydrocarbon having 6 to 30 ring backbone carbon atoms that can be partially saturated. The above aryl, arylene and arentriyl may comprise a spiro structure. The above aryl may include phenyl, biphenyl, terphenyl, quinquephenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, diphenylfluorenyl, benzofluorenyl, dibenzofluorenyl, phenanthrenyl, phenylphenanthrenyl, benzophenanthrenyl, anthracenyl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, chrysenyl, naphthacenyl, fluoranthenyl, spirobifluorenyl, spiro[fluorene-benzofluoren]yl, spiro[cyclopentene-fluoren]yl, spiro[dihydroindene-fluoren]yl, azulenyl, tetramethyldihydrophenanthrenyl, etc. Specifically, the above aryl may include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, benzanthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, 9-phenanthryl, naphthacenyl, pyrenyl, 1-chrysenyl, 2-chrysenyl, 3-chrysenyl, 4-chrysenyl, 5-chrysenyl, 6-chrysenyl, benzo[c]phenanthryl, benzo[g]chrysenyl, 1-triphenylenyl, 2-triphenylenyl, 3-triphenylenyl, 4-triphenylenyl, 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, 9-fluorenyl, benzo[a]fluorenyl, benzo[b]fluorenyl, benzo[c]fluorenyl, dibenzofluorenyl, 2-biphenyl, 3-biphenyl, 4-biphenyl, o-terphenyl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-quaterphenyl, 3-fluoranthenyl, 4-fluoranthenyl, 8-fluoranthenyl, 9-fluoranthenyl, benzofluoranthenyl, o-tolyl, m-tolyl, p-tolyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl, o-cumenyl, m-cumenyl, p-cumenyl, 4″-tert-butyl-p-terphenyl-4-yl, 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, 11,11-dimethyl-1-benzo[a]fluorenyl, 11,11-dimethyl-2-benzo[a]fluorenyl, 11,11-dimethyl-3-benzo[a]fluorenyl, 11,11-dimethyl-4-benzo[a]fluorenyl, 11,11-dimethyl-5-benzo[a]fluorenyl, 11,11-dimethyl-6-benzo[a]fluorenyl, 11,11-dimethyl-7-benzo[a]fluorenyl, 11,11-dimethyl-8-benzo[a]fluorenyl, 11,11-dimethyl-9-benzo[a]fluorenyl, 11,11-dimethyl-10-benzo[a]fluorenyl, 11,11-dimethyl-1-benzo[b]fluorenyl, 11,11-dimethyl-2-benzo[b]fluorenyl, 11,11-dimethyl-3-benzo[b]fluorenyl, 11,11-dimethyl-4-benzo[b]fluorenyl, 11,11-dimethyl-5-benzo[b]fluorenyl, 11,11-dimethyl-6-benzo[b]fluorenyl, 11,11-dimethyl-7-benzo[b]fluorenyl, 11,11-dimethyl-8-benzo[b]fluorenyl, 11,11-dimethyl-9-benzo[b]fluorenyl, 11,11-dimethyl-10-benzo[b]fluorenyl, 11,11-dimethyl-1-benzo[c]fluorenyl, 11,11-dimethyl-2-benzo[c]fluorenyl, 11,11-dimethyl-3-benzo[c]fluorenyl, 11,11-dimethyl-4-benzo[c]fluorenyl, 11,11-dimethyl-5-benzo[c]fluorenyl, 11,11-dimethyl-6-benzo[c]fluorenyl, 11,11-dimethyl-7-benzo[c]fluorenyl, 11,11-dimethyl-8-benzo[c]fluorenyl, 11,11-dimethyl-9-benzo[c]fluorenyl, 11,11-dimethyl-10-benzo[c]fluorenyl, 11,11-diphenyl-1-benzo[a]fluorenyl, 11,11-diphenyl-2-benzo[a]fluorenyl, 11,11-diphenyl-3-benzo[a]fluorenyl, 11,11-diphenyl-4-benzo[a]fluorenyl, 11,11-diphenyl-5-benzo[a]fluorenyl, 11,11-diphenyl-6-benzo[a]fluorenyl, 11,11-diphenyl-7-benzo[a]fluorenyl, 11,11-diphenyl-8-benzo[a]fluorenyl, 11,11-diphenyl-9-benzo[a]fluorenyl, 11,11-diphenyl-10-benzo[a]fluorenyl, 11,11-diphenyl-1-benzo[b]fluorenyl, 11,11-diphenyl-2-benzo[b]fluorenyl, 11,11-diphenyl-3-benzo[b]fluorenyl, 11,11-diphenyl-4-benzo[b]fluorenyl, 11,11-diphenyl-5-benzo[b]fluorenyl, 11,11-diphenyl-6-benzo[b]fluorenyl, 11,11-diphenyl-7-benzo[b]fluorenyl, 11,11-diphenyl-8-benzo[b]fluorenyl, 11,11-diphenyl-9-benzo[b]fluorenyl, 11,11-diphenyl-10-benzo[b]fluorenyl, 11,11-diphenyl-1-benzo[c]fluorenyl, 11,11-diphenyl-2-benzo[c]fluorenyl, 11,11-diphenyl-3-benzo[c]fluorenyl, 11,11-diphenyl-4-benzo[c]fluorenyl, 11,11-diphenyl-5-benzo[c]fluorenyl, 11,11-diphenyl-6-benzo[c]fluorenyl, 11,11-diphenyl-7-benzo[c]fluorenyl, 11,11-diphenyl-8-benzo[c]fluorenyl, 11,11-diphenyl-9-benzo[c]fluorenyl, 11,11-diphenyl-10-benzo[c]fluorenyl, 9,9,10,10-tetramethyl-9,10-dihydro-1-phenanthrenyl, 9,9,10,10-tetramethyl-9,10-dihydro-2-phenanthrenyl, 9,9,10,10-tetramethyl-9,10-dihydro-3-phenanthrenyl, 9,9,10,10-tetramethyl-9,10-dihydro-4-phenanthrenyl, etc.
The term “(3- to 30-membered)heteroaryl”, “(3- to 30-membered)heteroarylene”, and “(3- to 30-membered)heteroarentriyl” are meant to be an aryl group having 3 to 30 ring backbone atoms, and including at least one, preferably 1 to 4 heteroatoms selected from the group consisting of B, N, O, S, Si, P, Se, Te, and Ge. The above heteroaryl may be a monocyclic ring, or a fused ring condensed with at least one benzene ring; may be partially saturated; may be one formed by linking at least one heteroaryl or aryl group to a heteroaryl group via a single bond(s); and may comprise a spiro structure. The above heteroaryl may include a monocyclic ring-type heteroaryl such as furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, and pyridazinyl, and a fused ring-type heteroaryl such as benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, dibenzothiophenyl, dibenzoselenophenyl, naphthobenzofuranyl, naphthobenzothiophenyl, naphthooxazolyl, benzofuroquinolinyl, benzofuroquinazolinyl, benzofuronaphthyridinyl, benzofuropyrimidinyl, naphthofuropyrimidinyl, benzothienoquinolyl, benzothienoquinazolinyl, naphthyridinyl, benzothienonaphthyridinyl, benzothienopyrimidinyl, naphthothienopyrimidinyl, pyrimidoindolyl, benzopyrimidoindolyl, benzofuropyrazinyl, naphthofuropyrazinyl, benzothienopyrazinyl, naphthothienopyrazinyl, phenanthrooxazolyl, phenanthrothiazolyl, phenanthrobenzofuranyl, benzophenanthrothiophenyl, pyrazinoindolyl, benzopyrazinoindolyl, benzimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, benzoquinazolinyl, quinoxalinyl, benzoquinoxalinyl, carbazolyl, benzocarbazolyl, dibenzocarbazolyl, phenoxazinyl, phenanthridinyl, benzodioxolyl, dihydroacridinyl, benzotriazolyl, phenazinyl, imidazopyridyl, chromenoquinazolinyl, thiochromenoquinazolinyl, dimethylbenzoperimidinyl, indolocarbazolyl, indenocarbazolyl, etc. More specifically, the above heteroaryl may include 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, pyrazinyl, 2-pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 6-pyrimidinyl, 1,2,3-triazin-4-yl, 1,2,4-triazin-3-yl, 1,3,5-triazin-2-yl, 1-imidazolyl, 2-imidazolyl, 1-pyrazolyl, 1-indolidinyl, 2-indolidinyl, 3-indolidinyl, 5-indolidinyl, 6-indolidinyl, 7-indolidinyl, 8-indolidinyl, 2-imidazopyridyl, 3-imidazopyridyl, 5-imidazopyridyl, 6-imidazopyridyl, 7-imidazopyridyl, 8-imidazopyridyl, 3-pyridyl, 4-pyridyl, 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, 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-quinoxalinyl, 5-quinoxalinyl, 6-quinoxalinyl, 1-carbazolyl, 2-carbazolyl, 3-carbazolyl, 4-carbazolyl, 9-carbazolyl, azacarbazol-1-yl, azacarbazol-2-yl, azacarbazol-3-yl, azacarbazol-4-yl, azacarbazol-5-yl, azacarbazol-6-yl, azacarbazol-7-yl, azacarbazol-8-yl, azacarbazol-9-yl, 1-phenanthridinyl, 2-phenanthridinyl, 3-phenanthridinyl, 4-phenanthridinyl, 6-phenanthridinyl, 7-phenanthridinyl, 8-phenanthridinyl, 9-phenanthridinyl, 10-phenanthridinyl, 1-acridinyl, 2-acridinyl, 3-acridinyl, 4-acridinyl, 9-acridinyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 2-oxadiazolyl, 5-oxadiazolyl, 3-furazanyl, 2-thienyl, 3-thienyl, 2-methylpyrrol-1-yl, 2-methylpyrrol-3-yl, 2-methylpyrrol-4-yl, 2-methylpyrrol-5-yl, 3-methylpyrrol-1-yl, 3-methylpyrrol-2-yl, 3-methylpyrrol-4-yl, 3-methylpyrrol-5-yl, 2-tert-butylpyrrol-4-yl, 3-(2-phenylpropyl)pyrrol-1-yl, 2-methyl-1-indolyl, 4-methyl-1-indolyl, 2-methyl-3-indolyl, 4-methyl-3-indolyl, 2-tert-butyl-1-indolyl, 4-tert-butyl-1-indolyl, 2-tert-butyl-3-indolyl, 4-tert-butyl-3-indolyl, 1-dibenzofuranyl, 2-dibenzofuranyl, 3-dibenzofuranyl, 4-dibenzofuranyl, 1-dibenzothiophenyl, 2-dibenzothiophenyl, 3-dibenzothiophenyl, 4-dibenzothiophenyl, 1-naphtho-[1,2-b]-benzofuranyl, 2-naphtho-[1,2-b]-benzofuranyl, 3-naphtho-[1,2-b]-benzofuranyl, 4-naphtho-[1,2-b]-benzofuranyl, 5-naphtho-[1,2-b]-benzofuranyl, 6-naphtho-[1,2-b]-benzofuranyl, 7-naphtho-[1,2-b]-benzofuranyl, 8-naphtho-[1,2-b]-benzofuranyl, 9-naphtho-[1,2-b]-benzofuranyl, 10-naphtho-[1,2-b]-benzofuranyl, 1-naphtho-[2,3-b]-benzofuranyl, 2-naphtho-[2,3-b]-benzofuranyl, 3-naphtho-[2,3-b]-benzofuranyl, 4-naphtho-[2,3-b]-benzofuranyl, 5-naphtho-[2,3-b]-benzofuranyl, 6-naphtho-[2,3-b]-benzofuranyl, 7-naphtho-[2,3-b]-benzofuranyl, 8-naphtho-[2,3-b]-benzofuranyl, 9-naphtho-[2,3-b]-benzofuranyl, 10-naphtho-[2,3-b]-benzofuranyl, 1-naphtho-[2,1-b]-benzofuranyl, 2-naphtho-[2,1-b]-benzofuranyl, 3-naphtho-[2,1-b]-benzofuranyl, 4-naphtho-[2,1-b]-benzofuranyl, 5-naphtho-[2,1-b]-benzofuranyl, 6-naphtho-[2,1-b]-benzofuranyl, 7-naphtho-[2,1-b]-benzofuranyl, 8-naphtho-[2,1-b]-benzofuranyl, 9-naphtho-[2,1-b]-benzofuranyl, 10-naphtho-[2,1-b]-benzofuranyl, 1-naphtho-[1,2-b]-benzothiophenyl, 2-naphtho-[1,2-b]-benzothiophenyl, 3-naphtho-[1,2-b]-benzothiophenyl, 4-naphtho-[1,2-b]-benzothiophenyl, 5-naphtho-[1,2-b]-benzothiophenyl, 6-naphtho-[1,2-b]-benzothiophenyl, 7-naphtho-[1,2-b]-benzothiophenyl, 8-naphtho-[1,2-b]-benzothiophenyl, 9-naphtho-[1,2-b]-benzothiophenyl, 10-naphtho-[1,2-b]-benzothiophenyl, 1-naphtho-[2,3-b]-benzothiophenyl, 2-naphtho-[2,3-b]-benzothiophenyl, 3-naphtho-[2,3-b]-benzothiophenyl, 4-naphtho-[2,3-b]-benzothiophenyl, 5-naphtho-[2,3-b]-benzothiophenyl, 1-naphtho-[2,1-b]-benzothiophenyl, 2-naphtho-[2,1-b]-benzothiophenyl, 3-naphtho-[2,1-b]-benzothiophenyl, 4-naphtho-[2,1-b]-benzothiophenyl, 5-naphtho-[2,1-b]-benzothiophenyl, 6-naphtho-[2,1-b]-benzothiophenyl, 7-naphtho-[2,1-b]-benzothiophenyl, 8-naphtho-[2,1-b]-benzothiophenyl, 9-naphtho-[2,1-b]-benzothiophenyl, 10-naphtho-[2,1-b]-benzothiophenyl, 2-benzofuro[3,2-d]pyrimidinyl, 6-benzofuro[3,2-d]pyrimidinyl, 7-benzofuro[3,2-d]pyrimidinyl, 8-benzofuro[3,2-d]pyrimidinyl, 9-benzofuro[3,2-d]pyrimidinyl, 2-benzothio[3,2-d]pyrimidinyl, 6-benzothio[3,2-d]pyrimidinyl, 7-benzothio[3,2-d]pyrimidinyl, 8-benzothio[3,2-d]pyrimidinyl, 9-benzothio[3,2-d]pyrimidinyl, 2-benzofuro[3,2-d]pyrazinyl, 6-benzofuro[3,2-d]pyrazinyl, 7-benzofuro[3,2-d]pyrazinyl, 8-benzofuro[3,2-d]pyrazinyl, 9-benzofuro[3,2-d]pyrazinyl, 2-benzothio[3,2-d]pyrazinyl, 6-benzothio[3,2-d]pyrazinyl, 7-benzothio[3,2-d]pyrazinyl, 8-benzothio[3,2-d]pyrazinyl, 9-benzothio[3,2-d]pyrazinyl, 1-silafluorenyl, 2-silafluorenyl, 3-silafluorenyl, 4-silafluorenyl, 1-germafluorenyl, 2-germafluorenyl, 3-germafluorenyl, 4-germafluorenyl, 1-dibenzoselenophenyl, 2-dibenzoselenophenyl, 3-dibenzoselenophenyl, 4-dibenzoselenophenyl, etc. “Heteroaryl(ene)” may be classified into heteroaryl(ene) with electronic properties and heteroaryl(ene) with hole properties. Heteroaryl(ene) with electronic properties is a substituent that is relatively rich in electrons in the parent nucleus, for example, a substituted or unsubstituted pyridinyl, a substituted or unsubstituted pyrimidinyl, a substituted or unsubstituted triazinyl, a substituted or unsubstituted quinazolinyl, a substituted or unsubstituted quinoxalinyl, a substituted or unsubstituted quinolyl, etc.
Heteroaryl(ene) with hole properties is a substituent that is relatively electron-deficient in the parent nucleus, for example, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted dibenzofuranyl, a substituted or unsubstituted dibenzothiophenyl, etc. Herein, the term “halogen” includes F, Cl, Br, and I.
In addition, “ortho-” (“o-”), “meta-” (“ ”), and “para-” (“p-”) are prefixes which each represent the relative positions of substituents. The prefix “ortho-” indicates that two substituents are adjacent to each other, and for example, when two substituents in a benzene derivative occupy positions 1 and 2, or positions 2 and 3, this is called an “ortho-” configuration. The prefix “meta-” indicates that two substituents are at positions 1 and 3, and for example, when two substituents in a benzene derivative occupy positions 1 and 3, this is called a “meta-” configuration. The prefix “para-” indicates that two substituents are at positions 1 and 4, and for example, when two substituents in a benzene derivative occupy positions 1 and 4, this is called a “para-” configuration. Unless otherwise specified, the substituent may replace hydrogen at a position where the substituent can be substituted without limitation, and when two or more hydrogen atoms in a certain functional group are each replaced with a substituent, each substituent may be the same as or different from each other. The maximum number of substituents that can be substituted for a certain functional group may be the total number of valences that can be substituted for each atom forming the functional group.
Herein, the substituted alkyl, the substituted alkenyl, the substituted cycloalkyl, the substituted cycloalkenyl, the substituted heterocycloalkyl, the substituted silyl, the substituted aryl(ene), the substituted heteroaryl(ene), the substituted alkoxy, the substituted trialkylsilyl, the substituted dialkylarylsilyl, the substituted alkyldiarylsilyl, the substituted triarylsilyl, the substituted fused ring group of an aliphatic ring(s) and an aromatic ring(s), the substituted mono- or di-alkylamino, the substituted mono- or di-alkenylamino, the substituted mono- or di-arylamino, the substituted mono- or di-heteroarylamino, the substituted alkylalkenylamino, the substituted alkylarylamino, the substituted alkylheteroarylamino, the substituted alkenylarylamino, the substituted alkenylheteroarylamino, the substituted arylheteroarylamino, the substituted dibenzofuranyl, the substituted dibenzothiophenyl, or the substituted carbazolyl each independently, may be substituted by at least one selected from the group consisting of deuterium; a halogen; a cyano; a carboxyl; a nitro; a hydroxyl; a phosphine oxide; a (C1-C30)alkyl; a halo(C1-C30)alkyl; a (C2-C30)alkenyl; a (C2-C30)alkynyl; a (C1-C30)alkoxy; a (C1-C30)alkylthio; a (C3-C30)cycloalkyl; a (C3-C30)cycloalkenyl; a (3- to 7-membered)heterocycloalkyl; a (C6-C30)aryloxy; a (C6-C30)arylthio; a (C6-C30)aryl unsubstituted or substituted with at least one of a (C1-C30)alkyl(s) a (C6-C30)aryl(s), and a (3- to 30-membered)heteroaryl(s); a (3- to 30-membered)heteroaryl unsubstituted or substituted with a (C6-C30)aryl(s); a tri(C1-C30)alkylsilyl; a tri(C6-C30)arylsilyl(s); a di(C1-C30)alkyl(C6-C30)arylsilyl; a (C1-C30)alkyldi(C6-C30)arylsilyl; a fused ring group of an (C3-C30)aliphatic ring(s) and an (C6-C30)aromatic ring(s); amino; a mono- or di-(C1-C30)alkylamino; a mono- or di-(C2-C30)alkenylamino; a mono- or di-(C6-C30)arylamino unsubstituted or substituted with a (C1-C30)alkyl(s); a mono- or di-((3- to 30-membered)heteroarylamino; a (C1-C30)alkyl(C2-C30)alkenylamino; a (C1-C30)alkyl(C6-C30)arylamino; a (C1-C30)alkyl(3- to 30-membered)heteroarylamino; a (C2-C30)alkenyl(C6-C30)arylamino; a (C2-C30)alkenyl(3- to 30-membered)heteroarylamino; a (C6-C30)aryl(3- to 30-membered)heteroarylamino; a (C1-C30)alkylcarbonyl; a (C1-C30)alkoxycarbonyl; a (C6-C30)arylcarbonyl; a di(C6-C30)arylboronyl; a di(C1-C30)alkylboronyl; a (C1-C30)alkyl(C6-C30)arylboronyl; a (C6-C30)aryl(C1-C30)alkyl; and a (C1-C30)alkyl(C6-C30)aryl. According to one embodiment of the present disclosure, the substituted alkyl, etc. each independently are substituted by at least one selected from the group consisting of a (C1-C25)alkyl; a (C3-C25)cycloalkyl; a (C6-C25)aryl unsubstituted or substituted with at least one of a (C1-C30)alkyl(s) a (C6-C30)aryl(s), and a (3- to 30-membered)heteroaryl(s); a (3- to 25-membered)heteroaryl unsubstituted or substituted with a (C6-C30)aryl(s); and a mono- or di-(C6-C25)arylamino unsubstituted or substituted with a (C6-C30)aryl(s). For example, the substituted alkyl, etc. may be substituted by at least one selected from the group consisting of a methyl, a phenyl, a biphenyl, a terphenyl, a naphthyl, a naphthyl substituted with a phenyl(s), a naphthyl substituted with a naphthyl(s), a naphthyl substituted with a dibenzofuranyl(s), a phenanthrenyl, a triphenylene, a benzofluorenyl, a benzofluorenyl substituted with a methyl(s), a benzofluorenyl substituted with a phenyl(s), a carbazolyl, carbazolyl substituted with a phenyl(s), a dibenzofuranyl, a dibenzothiophenyl, a diphenylamino, a phenylbiphenylamino, etc.
In the present disclosure, if a substituent is not indicated in the formula or compound structure, it may mean that all possible positions for the substituent are hydrogen or deuterium. That is, in the case of deuterium, it is an isotope of hydrogen, and some hydrogen atoms may be the isotope deuterium, and in this case, the content of deuterium may be 0% to 100%. In the present disclosure, in cases where a substituent is not indicated in the formula or compound structure, if the substituent is not explicitly excluded, such as 0% deuterium, 100% hydrogen, and all substituents are hydrogen, hydrogen and deuterium may be used intermixed in a compound. The deuterium is one of the isotopes of hydrogen and an element with a deuteron consisting of one proton and one neutron as its nucleus. It can be represented as hydrogen-2, whose element symbol can also be written as D or 2H. The isotopes are atoms with the same atomic number (Z) but different mass numbers (A), and can also be interpreted as elements with the same number of protons but different numbers of neutrons.
In the present disclosure, “a combination thereof” refers to a combination of one or more elements from the corresponding list to form a known or chemically stable arrangement that can be envisioned by a person skilled in the art from the corresponding list. For example, alkyl and deuterium can be combined to form a partially or fully deuterated alkyl group; halogen and alkyl can be combined to form a halogenated alkyl substituent; and halogen, alkyl, and aryl can be combined to form a halogenated arylalkyl. For example, a preferred combination of substituents includes up to 50 atoms that are not hydrogen or deuterium, up to 40 atoms that are not hydrogen or deuterium, or up to 30 atoms that are not hydrogen or deuterium, but in many cases, a preferred combination of substituents may comprise up to 20 atoms that are not hydrogen or deuterium.
In the formula of the present disclosure, when there are multiple substituents represented by the same symbol, each substituent represented by the same symbol may be the same as or different from each other.
In the formulas of the present disclosure, when forming a ring by linking to adjacent substituents, the ring may be linked to an adjacent two or more substituent(s) to form a substituted or unsubstituted, mono- or polycyclic, (3- to 30-membered) alicyclic or aromatic ring, or a combination thereof. In addition, the formed ring may contain at least one heteroatom selected from B, N, O, S, Si, and P, preferably at least one heteroatom selected from N, O, and S. According to one embodiment of the present disclosure, the number of ring backbone atoms is (5- to 20-membered), and according to another embodiment of the present disclosure, the number of ring backbone atoms is (5- to 15-membered).
The present disclosure relates to an organic electroluminescent device comprising an anode, a hole transport zone, a light-emitting layer, an electron transport zone, and a cathode, wherein the hole transport zone, the light-emitting layer, and the electron transport zone each comprise a deuterated compound(s), and the structures of each of the compounds are the same as or different from each other.
According to one embodiment of the present disclosure, the organic electroluminescent device is provided wherein the hole transport zone is configured by sequentially stacking a hole injection layer, a hole transport layer composed of one or more layers, and a hole auxiliary layer or an electron-blocking layer composed of one or more layers on the anode, and wherein at least one of the layers comprises a deuterated compound(s).
According to one embodiment of the present disclosure, the organic electroluminescent device is provided wherein the electron transport zone is configured by sequentially stacking an electron buffer layer or a hole-blocking layer composed of one or more layers, an electron transport layer composed of one or more layers, and an electron injection layer on the light-emitting layer, and at least one of the layers comprises a deuterated compound(s).
According to one embodiment of the present disclosure, the organic electroluminescent device is provided wherein the light-emitting layer is composed of one or more layers, and at least one of the light-emitting layers comprises one or more deuterated compounds as a host.
According to one embodiment of the present disclosure, the organic electroluminescent device is provided wherein the light-emitting layer comprises a phosphorescent or fluorescent luminescent compound, and the compound comprises iridium (Ir), platinum (Pt), or boron (B) atoms.
According to one embodiment of the present disclosure, the organic electroluminescent device according to the present disclosure may comprise at least one layer of the hole transport zone comprising a compound represented by the following formula 1.
In formula 1,
According to one embodiment of the present disclosure, Ar1 to Ar3 each independently represent hydrogen, deuterium, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, or a substituted or unsubstituted mono- or di-(C6-C30)arylamino; preferably hydrogen, deuterium, a substituted or unsubstituted (C6-C26)aryl, a substituted or unsubstituted (3- to 13-membered)heteroaryl, or a substituted or unsubstituted mono- or di-(C6-C12)arylamino, with a proviso that each of Ar1 to each of Ar3 may comprise at least one of a substituted or unsubstituted (C6-C30)aryl(s) or a substituted or unsubstituted (3- to 30-membered)heteroaryl(s). More preferably, at least one of Ar1 to Ar3 represents a substituted or unsubstituted phenanthrenyl, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted fluorenyl, a substituted or unsubstituted benzofluorenyl, a substituted or unsubstituted triphenylenyl, a substituted or unsubstituted dibenzofuranyl, or a substituted or unsubstituted dibenzothiophenyl. For example, Ar1 to Ar3 each independently represent a substituted or unsubstituted fluorenyl, a substituted or unsubstituted benzofluorenyl, a substituted or unsubstituted spirobifluorenyl, a substituted or unsubstituted phenyl, a substituted or unsubstituted biphenyl, a substituted or unsubstituted terphenyl, a substituted or unsubstituted phenanthrenyl, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted dibenzothiophenyl, a substituted or unsubstituted dibenzofuranyl, a substituted or unsubstituted diphenylamino, or a substituted or unsubstituted phenylbiphenylamino, etc., with a proviso that each of Ar1 to each of Ar3 may comprise at least one of a substituted or unsubstituted (C6-C30)aryl(s) or a substituted or unsubstituted (3- to 30-membered)heteroaryl(s). In the above, the substituents of the substituted ones may be at least one selected from deuterium, a methyl(s), a phenyl(s), a biphenyl(s), a phenanthrenyl(s), a benzofluorenyl(s) substituted with a methyl(s), a benzofluorenyl(s) substituted with a phenyl(s), a carbazolyl(s), a carbazolyl(s) substituted with a phenyl(s), a dibenzofuranyl(s), a diphenylamino(s), and a phenylbiphenylamino(s).
According to one embodiment of the present disclosure, L1 to L3 each independently may represent a single bond, a substituted or unsubstituted (C6-C25)arylene, or a substituted or unsubstituted (3- to 25-membered)heteroarylene. Preferably, L1 to L3 each independently may represent a single bond, a substituted or unsubstituted (6-C12)arylene, or a substituted or unsubstituted (3- to 13-membered)heteroarylene. For example, L1 to L3 each independently may be a single bond, a substituted or unsubstituted phenylene, a biphenylene, a substituted or unsubstituted carbazolylene, a dibenzothiophenylene, or a dibenzofuranylene, etc. In the above, the substituents of the substituted ones may be at least one selected from deuterium, a phenyl(s), a carbazolyl(s), a carbazolyl(s) substituted with a phenyl(s), a dibenzofuranyl(s), and a dibenzothiophenyl(s).
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
According to one embodiment of the present disclosure, the deuterated compound may be more specifically exemplified as the following compounds, but is not limited thereto.
According to one embodiment of the present disclosure, the organic electroluminescent device of the present disclosure may comprise a compound represented by the following formula 2 or formula 3 in at least one layer of the electron transport zone.
In formula 2,
According to one embodiment of the present disclosure, L11 and L12 each independently may represent a single bond or a substituted or unsubstituted (C6-C30)arylene; preferably a single bond or a substituted or unsubstituted (C6-C25)arylene; more preferably a single bond or a substituted or unsubstituted (C6-C18)arylene. For example, L11 and L12 each independently may be a single bond or a phenylene.
According to one embodiment of the present disclosure, Ar11 and Ar12 each independently may represent a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (5- to 30-membered)heteroaryl; preferably, a substituted or unsubstituted (C6-C25)aryl or a substituted or unsubstituted (5- to 25-membered)heteroaryl; more preferably, a substituted or unsubstituted (C6-C25)aryl or a substituted or unsubstituted (5- to 20-membered)heteroaryl. For example, Ar11 and Ar12 each independently may be a substituted or unsubstituted phenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted m-biphenyl, a substituted or unsubstituted p-biphenyl, or a substituted or unsubstituted benzimidazolyl represented by the following formula 2-1 or 2-2.
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
In formula 2-1 and 2-2,
According to one embodiment of the present disclosure, L′1 may represent a single bond or a substituted or unsubstituted (C6-C30)arylene; preferably, a single bond or a substituted or unsubstituted (C6-C25)arylene; more preferably a single bond or a substituted or unsubstituted (C6-C18)arylene. For example, L′1 may be a single bond or a phenylene.
According to one embodiment of the present disclosure, R′1 to R′4 each independently may represent hydrogen or deuterium.
According to one embodiment of the present disclosure, R′5 may represent a substituted or unsubstituted (C1-C30)alkyl or a substituted or unsubstituted (C6-C30)aryl; preferably, a substituted or unsubstituted (C1-C10)alkyl or a substituted or unsubstituted (C6-C25)aryl; more preferably a substituted or unsubstituted (C1-C4)alkyl or a substituted or unsubstituted (C6-C18)aryl. For example, R′5 may be an ethyl, a phenyl, a naphthyl, or a biphenyl.
According to one embodiment of the present disclosure, R11 to R18 each independently may represent hydrogen, deuterium, or a substituted or unsubstituted benzimidazolyl represented by the following formula 2-1 or 2-2.
According to one embodiment of the present disclosure, at least one of R11 to R18, Ar11, and Ar12 may be a substituted or unsubstituted benzimidazolyl represented by the above formula 2-1 or 2-2.
In formula 3,
According to one embodiment of the present disclosure, at least two of X21 to X23 represent N, and preferably, all of X21 to X23 may represent N.
According to one embodiment of the present disclosure, L21 to L23 each independently may represent a single bond or a substituted or unsubstituted (C6-C30)arylene. Preferably, L21 to L23 each independently represent a single bond or a substituted or unsubstituted (C6-C25)arylene. More preferably, L21 to L23 each independently may represent a single bond or a substituted or unsubstituted (C6-C18)arylene. For example, L21 to L23 each independently may be a single bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted naphthylene, a substituted or unsubstituted p-biphenylene, a substituted or unsubstituted m-biphenylene, or a substituted or unsubstituted o-terphenylene. In the above, the substituents of the substituted ones may be at least one selected from deuterium, a phenanthrenyl(s), a pyridyl(s) unsubstituted or substituted with at least one of a methyl(s) or a phenyl(s), and quinolinyl(s).
According to one embodiment of the present disclosure, Ar21 to Ar23 each independently may represent a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (5- to 30-membered)heteroaryl; preferably, a substituted or unsubstituted (C6-C25)aryl or a substituted or unsubstituted (5- to 26-membered)heteroaryl; and more preferably, a substituted or unsubstituted (C6-C18)aryl or a substituted or unsubstituted (5- to 26-membered)heteroaryl. Preferably, at least one of Ar21 to Ar23 may comprise a substituted or unsubstituted phenanthrenyl, a substituted or unsubstituted carbazolyl, a substituted or unsubstituted fluorenyl, a substituted or unsubstituted benzofluorenyl, a substituted or unsubstituted triphenylenyl, a substituted or unsubstituted dibenzofuranyl, or a substituted or unsubstituted dibenzothiophenyl, with a proviso that at least one of Ar21 to Ar23 comprises deuterium. For example, Ar21 to Ar23 each independently represent a substituted or unsubstituted phenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted p-biphenyl, a substituted or unsubstituted m-biphenyl, a substituted or unsubstituted phenanthrenyl, a substituted or unsubstituted fluorenyl, a substituted or unsubstituted pyridyl, a substituted or unsubstituted triazinyl, a substituted or unsubstituted quinolinyl, a substituted or unsubstituted spiro[fluorene-9,9′-xanthene]yl, or a 22-membered heteroaryl, and the substituents of the substituted ones may be at least one selected from deuterium, a cyano(s), a methyl(s), a phenyl(s), a biphenyl(s), and a naphthyl(s).
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
According to one embodiment of the present disclosure, the deuterated compound may be more specifically exemplified as the following compounds, but is not limited thereto.
According to one embodiment of the present disclosure, the organic electroluminescent device according to the present disclosure may comprise at least one layer in the light-emitting layer comprising a compound represented by the following formula 4 or formula 5.
In formula 4,
According to one embodiment of the present disclosure, A1 and A2 each independently may represent a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted dibenzofuranyl. Preferably A1 and A2 each independently may represent a substituted or unsubstituted (C6-C18)aryl or a substituted or unsubstituted dibenzofuranyl. For example, A1 and A2 each independently may be a substituted or unsubstituted phenyl, a biphenyl, a substituted or unsubstituted naphthyl, a terphenyl, a triphenylenyl, or a substituted or unsubstituted dibenzofuranyl. The substituents of the above substituted ones may be at least one selected from deuterium, a phenyl(s), a naphthyl(s), a triphenylenyl(s), and a dibenzofuranyl(s).
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
In formula 5,
R51 to R53 and R′51 to R′59 each independently represent hydrogen, deuterium, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C1-C30)alkoxy, a substituted or unsubstituted 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 fused ring group of a (C3-C30) aliphatic ring(s) and a (C6-C30) aromatic ring(s), a substituted or unsubstituted mono- or di-(C1-C30)alkylamino, a substituted or unsubstituted mono- or di-(C2-C30)alkenylamino, a substituted or unsubstituted (C1-C30)alkyl(C2-C30)alkenylamino, a substituted or unsubstituted mono- or di-(C6-C30)arylamino, a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino, a substituted or unsubstituted mono- or di-(3- to 30-membered)heteroarylamino, a substituted or unsubstituted (C1-C30)alkyl(3- to 30-membered)heteroarylamino, a substituted or unsubstituted (C2-C30)alkenyl(C6-C30)arylamino, a substituted or unsubstituted (C2-C30)alkenyl(3- to 30-membered)heteroarylamino, or a substituted or unsubstituted (C6-C30)aryl(3- to 30-membered)heteroarylamino, or may be linked to adjacent substituent(s) to form a ring(s);
According to one embodiment of the present disclosure, R51 to R53 and R′51 to R′59 each independently may represent hydrogen, deuterium, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted fused ring group of a (C3-C30) aliphatic ring(s) and a (C6-C30) aromatic ring(s), 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 adjacent substituent(s) to form a ring(s). Preferably, R51 to R53 and R′51 to R′59 each independently may represent a substituted or unsubstituted (C6-C25)aryl, a substituted or unsubstituted (5- to 25-membered)heteroaryl, a substituted or unsubstituted fused ring group of a (C3-C30) aliphatic ring(s) and a (C6-C30) aromatic ring(s), a substituted or unsubstituted mono- or di-(C6-C18)arylamino, or may be linked to adjacent substituent(s) to form a ring(s). For example, R51 to R53 and R′51 to R′59 each independently may be a phenyl unsubstituted or substituted with a phenyl, a naphthyl, a biphenyl, a terphenyl, a phenanthrenyl, a 23-membered heteroaryl, a dibenzofuranyl, a dibenzothiophenyl, a diphenylamino, a phenylbiphenylamino, a phenylnaphthylamino, a dibiphenylamino, formula 5-1, or formula 5-2, etc., or may be linked to adjacent substituent(s) to form a benzoindolocarbazole ring such as formula 5-3 or formula 5-4, which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, X″ may represent O.
According to one embodiment of the present disclosure, L51 to L55 each independently may represent a single bond or a substituted or unsubstituted (C6-C30)arylene. Preferably, L51 to L55 each independently may represent a single bond or a substituted or unsubstituted (C6-C12)arylene. For example, L51 to L53 each independently may be a single bond, a phenyl, or a biphenyl, etc., which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
According to one embodiment of the present disclosure, the deuterated compound may be more specifically exemplified as the following compounds, but is not limited thereto.
According to one embodiment of the present disclosure, the organic electroluminescent device according to the present disclosure may comprise at least one layer in the light-emitting layer comprising two or more compounds, wherein the two or more compounds comprise a compound represented by the following formula 6 or formula 7.
In formula 6 and formula 7,
According to one embodiment of the present disclosure, HAr61 and HAr62 each independently may represent a substituted or unsubstituted (3- to 15-membered)heteroaryl containing one or more nitrogen atoms. For example, HAr61 and HAr62 each independently may be a substituted triazinyl, wherein the substituent(s) of the substituted triazinyl may be at least one, preferably two, selected from a naphthyl(s), a biphenyl(s), a terphenyl(s), a naphthyl(s) substituted with a phenyl(s), a naphthyl(s) substituted with a naphthyl(s), a naphthyl substituted with dibenzofuranyl, and a dibenzofuranyl(s), which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, L61 and L62 each independently may represent a single bond or a substituted or unsubstituted (C6-C15)arylene. Preferably, L61 and L62 each independently may represent a single bond or a substituted or unsubstituted (C6-C10)arylene. For example, L61 and L62 each independently may be a single bond, a phenylene, a naphthylene, etc., which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, R61 to R64 each independently may represent hydrogen, deuterium, a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (3- to 20-membered)heteroaryl; or may be linked to an adjacent substituent(s) to form a ring(s). Preferably, R61 to R64 each independently may represent hydrogen, deuterium, a substituted or unsubstituted (C6-C18)aryl, or a substituted or unsubstituted (3- to 20-membered)heteroaryl; or may be linked to an adjacent substituent(s) to form a ring(s). For example, R61 to R64 each independently may be hydrogen, deuterium, a naphthyl, a carbazolyl, a dibenzothiophenyl, a dibenzofuranyl, etc., or may be linked to an adjacent substituent(s) to form an indole ring substituted with a phenyl(s) or a biphenyl(s), a benzothiophene ring, or a benzene ring, etc., which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
According to one embodiment of the present disclosure, the deuterated compound may be more specifically exemplified as the following compounds, but is not limited thereto.
According to one embodiment of the present disclosure, the organic electroluminescent device of the present disclosure may comprise at least one layer in the light-emitting layer comprising a compound represented by the following formula 8.
In formula 8,
According to one embodiment of the present disclosure, Ar81 may represent a substituted or unsubstituted (C6-C30)aryl. Preferably, Ar81 may represent a substituted or unsubstituted (C6-C18)aryl. For example, Ar81 may be a phenyl unsubstituted or substituted with a naphthyl(s), a naphthyl, or a biphenyl, etc., which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, R81 to R88 each independently may represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C2-C30)alkenyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted (C3-C30)cycloalkyl, or a substituted or unsubstituted (C3-C30)cycloalkenyl. Preferably, R81 to R88 each independently may represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C2-C30)alkenyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl. For example, R81 to R88 each independently may be hydrogen or deuterium.
According to one embodiment of the present disclosure, ArA may represent a substituted or unsubstituted (C6-C25)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl, or may be represented by the above formula A-1. Preferably, ArA may represent a substituted or unsubstituted (C6-C13)aryl, or a substituted or unsubstituted (13- to 17-membered)heteroaryl, or may be represented by the above formula A-1. For example, ArA may be a substituted or unsubstituted phenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted benzofluorenyl, a dibenzofuranyl, or a benzonaphthofuranyl, or may be the above formula A-1, wherein the substituents of the above substituted ones may be at least one selected from deuterium, a methyl, a phenyl, a naphthyl, and a dibenzofuranyl.
According to one embodiment of the present disclosure, T1 may represent O or S. For example, T1 may be O.
According to one embodiment of the present disclosure, R′81 to R′88 each independently may be a site linked to L82, or may represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C2-C30)alkenyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, or a substituted or unsubstituted (C3-C30)cycloalkyl. Preferably, R′81 to R′88 each independently may be a site linked to L82, or may represent hydrogen, deuterium, or an unsubstituted (C6-C18)aryl. For example, R′81 to R′88 each independently may be a site linked to L82, or hydrogen, deuterium, or a phenyl, etc., which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, L81 to L83 each independently may represent a single bond, or a substituted or unsubstituted (C6-C30)arylene. Preferably, L81 to L83 each independently may represent a single bond, or a substituted or unsubstituted (C6-C15)arylene. For example, L81 to L83 each independently may represent a single bond, a phenylene, a naphthylene, or a phenanthrenylene, etc., which may be further substituted with one or more deuterium atoms.
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
According to one embodiment of the present disclosure, the deuterated compound may be more specifically exemplified as the following compounds, but is not limited thereto.
According to one embodiment of the present disclosure, the organic electroluminescent device of the present disclosure may include at least one layer in the light-emitting layer comprising a compound represented by the following formula 9.
In formula 9,
According to one embodiment of the present disclosure, A1 and A3 each independently may represent a substituted or unsubstituted (C6-C18)aryl, a substituted or unsubstituted dibenzofuranyl, or a substituted or unsubstituted carbazolyl. For example, A1 and A3 each independently may be a substituted or unsubstituted naphthyl, a substituted or unsubstituted phenyl, a substituted or unsubstituted p-biphenyl, a substituted or unsubstituted m-biphenyl, a substituted or unsubstituted p-terphenyl, a substituted or unsubstituted m-terphenyl, a substituted or unsubstituted o-terphenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted dibenzofuranyl, or a substituted or unsubstituted carbazolyl, etc, wherein the substituents of the above substituted ones may be at least one selected from deuterium, a phenyl, a carbazolyl unsubstituted or substituted with a phenyl(s), and a naphthyl.
According to one embodiment of the present disclosure, L3 and L5 each independently may represent a single bond, or a substituted or unsubstituted (C6-C12)arylene. For example, L3 and L5 each independently may represent a single bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted p-biphenylene, a substituted or unsubstituted m-biphenylene, a substituted or unsubstituted o-biphenylene, or a substituted or unsubstituted naphthylene, etc., wherein the substituents of the above substituted ones may be at least one selected from deuterium and carbazolyl.
According to one embodiment of the present disclosure, X15 to X18, which do not form a ring, X11 to X14, and X31 to X34 each independently may represent hydrogen or deuterium.
According to one embodiment of the present disclosure, the deuterium substitution rate is preferably 20% to 100% of the total number of hydrogens, more preferably 20% to 95%, even more preferably 30% to 95%, and even more preferably 40% to 95%.
According to one embodiment of the present disclosure, in the organic electroluminescent device of the present disclosure X11 or X31 may represent deuterium.
According to one embodiment of the present disclosure, the compound represented by formula 9 may be represented by any one of the following formulas 9-1 to 9-6.
In formulas 9-1 to 9-6, A1, A3, L3, L5, X11 to X18, X31 to X34, and Dn are as defined in formula 9 and formula 9-A.
According to one embodiment of the present disclosure, the deuterated compound may be more specifically exemplified as the following compounds, but is not limited thereto.
In the above compounds, Dn represents that n number of hydrogens are replaced with deuterium, and n represents an integer of 1 or more, and has an upper limit of the number of hydrogen atoms in the non-deuterated compound.
In the synthesis of the compounds represented by formulas 1 to 9 above, one skilled in the art will be able to readily understand that all of these are based on a Buchwald-Hartwig cross coupling reaction, an N-arylation reaction, an H-mont-mediated etherification reaction, a Miyaura borylation reaction, a Suzuki cross-coupling reaction, an intramolecular acid-induced cyclization reaction, a Pd(II)-catalyzed oxidative cyclization reaction, a Grignard reaction, a Heck reaction, a cyclic dehydration reaction, an SN1 substitution reaction, an SN2 substitution reaction, a phosphine-mediated reductive cyclization reaction, and Wittig reaction, etc., and the above reactions proceed even when substituents defined in formulas 1 to 9 other than those substituents specified in the specific synthesis examples are bonded.
Hereinafter, the above-mentioned compounds and an organic electroluminescent device comprising the same will be described.
The organic layer of the present disclosure may include at least one layers selected from a hole transport layer, a light-emitting layer, a hole injection layer, a hole auxiliary layer, a light-emitting auxiliary layer, an electron transport layer, an electron injection layer, an interlayer, a hole-blocking layer, an electron-blocking layer, and an electron buffer layer. The organic layer may further comprise an amine-based compound and/or an azine-based compound. Specifically, the hole injection layer, the hole transport layer, the hole auxiliary layer, the light-emitting layer, the light-emitting auxiliary layer, or the electron-blocking layer may comprise an amine-based compound, for example, an arylamine-based compound, a styrylarylamine-based compound, etc., as a hole injection material, a hole transport material, a hole auxiliary material, a light-emitting material, a light-emitting auxiliary material, and an electron-blocking material. In addition, the electron transport layer, the electron injection layer, the electron buffer layer, and the hole-blocking layer may comprise an azine-based compound as an electron transport material, an electron injection material, an electron buffer material, and a hole-blocking material. In addition, the organic layer may further comprise at least one metal selected from the group consisting of metals of Group 1, metals of Group 2, transition metals of the 4th period, transition metals of the 5th period, lanthanides, and organic metals of the d-transition elements of the Periodic Table, or at least one complex compound comprising the metal thereof.
A hole transport zone comprising a hole injection layer, a hole transport layer, an electron-blocking layer, or a combination thereof is included between the anode and the light-emitting layer. The hole injection layer may be composed of multiple layers for the purpose of lowering the hole injection barrier (or hole injection voltage) from the anode to the hole transport layer or electron-blocking layer, and each layer may use two compounds simultaneously. In addition, the hole injection layer may be doped with a p-type dopant. The electron-blocking layer may be placed between the hole transport layer (or hole injection layer) and the light-emitting layer, and may block the overflow of electrons from the light-emitting layer and confine the excitons in the light-emitting layer to prevent light leakage. The hole transport layer or electron-blocking layer may use multiple layers, and multiple compounds may be used in each layer.
An electron transport zone is included between the light-emitting layer and the cathode, including an electron buffer layer, a hole-blocking layer, an electron transport layer, an electron injection layer, or a combination thereof. The electron buffer layer may be multi-layers in order to control the injection of the electron and improve the interfacial properties between the light-emitting layer and the electron injection layer, wherein each of the multi-layers may use two compounds simultaneously. The hole-blocking layer is located between the electron transport layer (or electron injection layer) and the light-emitting layer and is a layer that blocks holes from reaching the cathode, thereby improving the probability of recombination of electrons and holes in the light-emitting layer. The hole-blocking layer or electron transport layer may also use multiple layers, and multiple compounds may be used in each layer. In addition, the electron injection layer may be doped with an n-type dopant.
The light-emitting auxiliary layer may be a layer placed between an anode and a light-emitting layer, or between a cathode and a light-emitting layer. When the light-emitting auxiliary layer is placed between the anode and the light-emitting layer, the light-emitting auxiliary layer may be used to facilitate hole injection and/or hole transport or to block the overflow of electrons. When the light-emitting auxiliary layer is placed between the cathode and the light-emitting layer, the light-emitting auxiliary layer may be used to facilitate electron injection and/or electron transport or to block the overflow of holes. In addition, the hole auxiliary layer may be placed between the hole transport layer (or hole injection layer) and the light-emitting layer, and may exhibit an effect of facilitating or blocking the hole transport rate (or hole injection rate), and accordingly may adjust the charge balance. When an organic electroluminescent device includes two or more hole transport layers, the hole transport layer, which is further included, may be used as a hole auxiliary 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, it is preferable to dispose at least one layer selected from a chalcogenide layer, a metal halide layer, and a metal oxide layer (hereinafter referred to as “surface layer”) on at least one inner surface of a pair of electrodes. Specifically, a chalcogenide (including oxide) layer of silicon and aluminum is preferably placed on an anode surface of an electroluminescent medium layer side, and a metal halide layer or a metal oxide layer is preferably placed on a cathode surface of an electroluminescent medium layer side. Driving stabilization of the organic electroluminescent device can be obtained by the surface layer. Preferred examples of the chalcogenide include SiOX(1≤X≤2), AlOX(1≤X≤1.5), SiON, SiAlON, etc., preferred examples of the metal halide include LiF, MgF2, CaF2, a rare earth metal fluoride, etc., and preferred examples of the metal oxide include Cs2O, Li2O, MgO, SrO, BaO, CaO, etc.
In addition, in an 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 placed on at least one surface of a pair of electrodes. In this case, the electron transport compound is reduced to an anion, and thus it becomes easier to inject and transport electrons from the mixed region to the light-emitting medium. Furthermore, the hole transport compound is oxidized to a cation, and thus it becomes easier to inject and transport holes from the mixed region to the light-emitting medium. Preferred oxidative dopants include various Lewis acids and acceptor compounds, and preferred reductive dopants include alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, and mixtures thereof. In addition, an organic electroluminescent device having at least two light-emitting layers and emitting white light may be manufactured by using the reductive dopant layer as a charge-generating layer.
An organic electroluminescent device according to the present disclosure may be an organic electroluminescent device having a tandem structure. In the case of the tandem organic electroluminescent device according to one embodiment, a single light-emitting unit (light-emitting part) may be formed in a structure in which two or more units are connected by a charge generation layer. The organic electroluminescent device may include a plurality of two or more light-emitting units, for example, a plurality of three or more light-emitting units, having first and second electrodes opposed to each other on a substrate and a light-emitting layer stacked between the first and second electrodes and emits light in a specific wavelength range. It may include a plurality of light-emitting units, and each of the light-emitting units may include a hole transport zone, a light-emitting layer, and an electron transport zone, and the hole transport zone may include a hole injection layer and a hole transport layer, the electron transport zone may include an electron transport layer and an electron injection layer. According to one embodiment of the present disclosure, three or more light-emitting layers may be included in the light-emitting unit. A plurality of light-emitting units may emit the same color or different colors. Additionally, one light-emitting unit may include one or more light-emitting layers, and the plurality of light-emitting layers may be light-emitting layers of the same or different colors. This may include one or more charge generation layers located between each light-emitting unit. The charge generation layer refers to the layer in which holes and electrons are generated when voltage is applied. When there are three or more light-emitting units, a charge generation layer may be located between each light-emitting unit. Here, the plurality of charge generation layers may be the same as or different from each other. By disposing the charge generating layer between light-emitting units, current efficiency is increased in each light-emitting unit, and charges can be smoothly distributed. Specifically, the charge generation layer is provided between two adjacent stacks and can serve to drive a tandem organic electroluminescent device using only a pair of anodes and cathodes without a separate internal electrode located between the stacks.
The charge generation layer may be composed of an N-type charge generation layer and a P-type charge generation layer, and the N-type charge generation layer may be doped with an alkali metal, an alkaline earth metal, or a compound of an alkali metal and an alkaline earth metal. The alkali metal may include one selected from the group consisting of Li, Na, K, Rb, Cs, Fr, Yb, and combinations thereof, and the alkaline earth metal may include one selected from the group consisting of Be, Mg, Ca, Sr, Ba, Ra, and combinations thereof. The P-type charge generation layer may be made of a metal or an organic material doped with a P-type dopant. For example, the metal may be made of one or two or more alloys selected from the group consisting of Al, Cu, Fe, Pb, Zn, Au, Pt, W, In, Mo, Ni, and Ti. Additionally, commonly used materials may be used as the P-type dopant and host materials used in the P-type doped organic material.
The manufacturing method of the organic electroluminescent device of the present disclosure is not limited, and the manufacturing method of the Device Example as described below is only an example, and the method is not limited thereto. One skilled in the art can reasonably modify the manufacturing method of the Device Examples as described below by relying on existing technology. For example, there is no particular limitation on the mixing ratio of the first compound and the second compound, and thus one skilled in the art can reasonably select this within a certain range by depending on existing technology. For example, based on the total weight of the light-emitting layer material, the total weight of the first compound and the second compound accounts for 99.5-80.0% of the total weight of the light-emitting layer, the weight ratio of the first compound and the second compound is between 1:99 and 99:1, the weight ratio of the first compound and the second compound may be between 20:80 and 99:1, or the weight ratio of the first compound and the second compound may be between 50:50 and 90:10. In the manufacture of devices, when forming a light-emitting layer by co-depositing two or more host materials and a light-emitting material, the two or more host materials and the light-emitting material may each be placed in different evaporation sources and co-deposited to form a light-emitting layer, or a pre-mixed mixture of two or more host materials may be placed on the same evaporation source and then co-deposited with a light-emitting material placed on another evaporation source to form a light-emitting layer. This premixing method can further save evaporation sources. According to one embodiment, the first compound, the second compound, and the light-emitting material of the present disclosure may each be placed in different evaporation sources and co-deposited to form a light-emitting layer, or a pre-mixed mixture of the first compound and the second compound may be placed in the same evaporation source and then co-deposited with a light-emitting material placed in another evaporation source to form a light-emitting layer.
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 spin coating, dip coating, flow coating methods, etc. can be used. When using a wet film-forming method, a thin film may be formed by dissolving or diffusing materials forming each layer into any suitable solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc. The solvent may be any solvent where the materials forming each layer can be dissolved or diffused, and where there are no problems in film-formation capability.
When forming a film of an organic electroluminescent material according to one embodiment, the film can be formed by the above-listed methods, and can be formed commonly by a co-deposition or mixed deposition process. The co-deposition is a method of mixing and depositing two or more materials by placing them in separate crucible sources and applying current to two cells simultaneously to evaporate the materials, and the mixed deposition is a method of mixing two or more materials in one crucible source before deposition and then applying current to one cell to evaporate the materials.
Hereinafter, for detailed understanding of the present disclosure, a method of preparing a compound according to the present disclosure will be described using the synthesis of a representative compound or intermediate compound of the present disclosure as an example.
Compound HT-ref1 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound HT′-47 (17 g, yield: 65%).
Compound H1-ref1 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound H1-55 (53 g, yield: 84%/).
Compound H2-ref1 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound H2-35 (66, yield: 91%).
Compound ET-ref1 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound ET-60 (12 g, yield: 87%/).
Compound HT-ref2 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound HT′-39 (7.6 g, yield: 63%).
Compound H2-ref2 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound H2-61 (8.1 g, yield: 75%).
Compound H1-ref2 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound H1-15 (32 g, yield: 84%).
Compound ET-ref2 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound ET-1 (5 g, yield: 88%).
Compound H3-ref1 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound H3-7 (12 g, yield: 77%).
Compound H3-ref2 was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound H3-20 (14 g, yield: 79%).
Compound C-52-ref was synthesized using the deuteration methods disclosed in Korean Patent Publication Nos. 10-2283849, 10-1427457, etc. to obtain compound C-52 (24.4 g, yield: 94%).
An OLED according to the present disclosure was produced. First, a transparent electrode indium tin oxide (ITO) thin film (10 Ω/sq) on a glass substrate for an OLED (GEOMATEC CO., LTD., Japan) was subjected to an ultrasonic washing with acetone and isopropyl alcohol, sequentially, and was then stored in isopropyl alcohol. The ITO substrate was mounted on a substrate holder of a vacuum vapor deposition apparatus. Compound HI (p-dopant) was introduced into a cell of the vacuum vapor deposition apparatus, and compound HT′-1 was introduced into another cell. The two materials were evaporated at different rates, and compound HI was deposited in a doping amount of 3 wt % based to the total amount of compound HI and compound HT′-1 to form a hole injection layer with a thickness of 10 nm. Subsequently, compound HT′-1 was deposited on the hole injection layer to form a first hole transport layer with a thickness of 80 nm. Next, the compound shown in Table 1 was introduced into another cell of the vacuum vapor deposition apparatus and was evaporated by applying an electric current to the cell, thereby depositing a second hole transport layer with a thickness of 30 nm. After forming the hole injection layer and the hole transport layers, a light-emitting layer was deposited thereon as follows: the compounds shown in Table 1 below were introduced into a cell of the vacuum vapor deposition apparatus as hosts at a ratio of 1:2, and compound GD was introduced into another cell as a dopant. The materials were evaporated at a different rate, and the dopant was deposited in a doping amount of 10 wt % based on the total amount of the hosts and dopant to form a light-emitting layer with a thickness of 40 nm on the second hole transport layer. The compounds shown in Table 1 were deposited with a thickness of 5 nm as an electron buffer layer, and then compound EI-1 and compound Liq were introduced into two other cells and evaporated at a rate of 1:1 to deposit an electron transport layer with a thickness of 30 nm on the electron buffer layer. After introducing compound Liq as an electron injection layer and depositing with a thickness of 2 nm on the electron transport layer, an A1 cathode was deposited with a thickness of 80 nm by using another vacuum vapor deposition apparatus, thereby producing an OLED. All of the materials used for producing the OLED were purified by vacuum sublimation at 10−6 Torr.
An OLED was produced in the same manner as in Device Example 1, except that the hole transport layer, the host material of the light-emitting layer, and the electron buffer layer were made of light hydrogen material.
Table 1 below shows the current efficiency at a luminance of 1,000 nit and time taken for luminance to reduce from 100% to 95% at a luminance of 40,000 nit (lifetime: T95) for the OLEDs of Device Example 1 and Comparative Example 1 produced as described above.
Comparative Example 1
From Table above, it can be confirmed that the organic electroluminescent device according to the present disclosure exhibits a longer lifetime property while maintaining current efficiency property compared to a conventional organic electroluminescent device.
An OLED according to the present disclosure was produced. First, a transparent electrode indium tin oxide (ITO) thin film (10 Ω/sq) on a glass substrate for an OLED (GEOMATEC CO., LTD., Japan) was subjected to an ultrasonic washing with acetone and isopropyl alcohol, sequentially, and was then stored in isopropyl alcohol. The ITO substrate was mounted on a substrate holder of a vacuum vapor deposition apparatus. Compound HI (p-dopant) was introduced into a cell of the vacuum vapor deposition apparatus, and compound HT′-1 was introduced into another cell. The two materials were evaporated at different rates, and compound HI was deposited in a doping amount of 3 wt % based to the total amount of compound HI and compound HT′-1 to form a hole injection layer with a thickness of 10 nm. Subsequently, compound HT′-1 was deposited on the hole injection layer to form a first hole transport layer with a thickness of 90 nm. Next, the compound shown in Table 2 was introduced into another cell of the vacuum vapor deposition apparatus as a second hole transport layer and was evaporated by applying an electric current to the cell, thereby depositing with a thickness of 60 nm on the first hole transport layer. After forming the hole injection layer and the hole transport layers, a light-emitting layer was deposited thereon as follows: the compounds shown in Table 2 below were introduced into a cell of the vacuum vapor deposition apparatus as hosts at a ratio of 1:1, and compound RD was introduced into another cell as a dopant. The materials were evaporated at a different rate, and the dopant was deposited in a doping amount of 3 wt % based on the total amount of the hosts and dopant to form a light-emitting layer with a thickness of 40 nm on the second hole transport layer. The compound shown in Table 2 was deposited with a thickness of 5 nm as an electron buffer layer, and then compound EI-1 and compound Liq were introduced into two other cells and evaporated at a rate of 1:1 to deposit an electron transport layer with a thickness of 30 nm on the light-emitting layer. After introducing compound Liq as an electron injection layer with a thickness of 2 nm on the electron transport layer, an A1 cathode was deposited with a thickness of 80 nm by using another vacuum vapor deposition apparatus, thereby producing an OLED. All of the materials used for producing the OLED were purified by vacuum sublimation at 10−6 Torr.
An OLED was produced in the same manner as in Device Example 2, except that the hole transport layer, the host material of the light-emitting layer, and the electron buffer layer were made of light hydrogen material.
Table 2 below shows the current efficiency at a luminance of 1,000 nit and time taken for luminance to reduce from 100% to 97% at a luminance of 10,000 nit (lifetime: T97) for the OLEDs of Device Example 2 and Comparative Example 2 produced as described above.
Comparative Example 2
From Table 2 above, it can be confirmed that the organic electroluminescent device according to the present disclosure exhibits higher current efficiency and much higher lifetime compared to a conventional organic electroluminescent device.
An OLED was produced in the same manner as in Device Example 2, except that the compound shown in Table 3 and compound Liq were introduced into two other cells and evaporated at a rate of 1:1 to deposit an electron transport layer with a thickness of 35 nm on the light-emitting layer without an electron buffer layer.
An OLED was produced in the same manner as in Device Example 3, except that the hole transport layer, the host material of the light-emitting layer, and the electron transport layer were made of light hydrogen material.
Table 3 below shows the current efficiency at a luminance of 1,000 nit and time taken for luminance to reduce from 100% to 97% at a luminance of 10,000 nit (lifetime: T97) for the OLEDs of Device Example 3 and Comparative Example 3 produced as described above.
Comparative Example 3
From Table 3 above, it can be confirmed that the organic electroluminescent device according to the present disclosure exhibits higher lifetime while maintaining current efficiency compared to a conventional organic electroluminescent device.
OLEDs according to the present disclosure were produced. First, a transparent electrode indium tin oxide (ITO) thin film (10 Ω/sq) on a glass substrate for an OLED (GEOMATEC CO., LTD., Japan) was subjected to an ultrasonic washing with acetone and isopropyl alcohol, sequentially, and was then stored in isopropyl alcohol. The ITO substrate was mounted on a substrate holder of a vacuum vapor deposition apparatus. Compound HI (p-dopant) was introduced into a cell of the vacuum vapor deposition apparatus, and compound HT′-1 was introduced into another cell. The two materials were evaporated at different rates, and compound HI was deposited in a doping amount of 3 wt % based to the total amount of compound HI and compound HT′-1 to form a hole injection layer with a thickness of 10 nm. Subsequently, compound HT′-1 was deposited on the hole injection layer to form a first hole transport layer with a thickness of 80 nm. Next, the compound shown in Table 4 was introduced into another cell of the vacuum vapor deposition apparatus as a second hole transport layer and was evaporated by applying an electric current to the cell, thereby depositing with a thickness of 5 nm on the first hole transport layer. After forming the hole injection layer and the hole transport layers, a light-emitting layer was deposited thereon as follows: After introducing the compound shown in Table 4 as a host in a cell in a vacuum vapor deposition apparatus, the two materials were evaporated at different rates, and the dopant was deposited in a doping amount of 2 wt % based on the total amount of the hosts and dopant to form a light-emitting layer with a thickness of 20 nm on the second hole transport layer. Then the compound shown in Table 4 and compound Liq were introduced to two other cells and evaporated at a rate of 1:1 to deposit an electron transport layer with a thickness of 35 nm on the light-emitting layer. After introducing compound Liq as an electron injection layer and depositing with a thickness of 2 nm on the electron transport layer, an A1 cathode was deposited with a thickness of 80 nm by using another vacuum vapor deposition apparatus, thereby producing an OLED. All the materials used for producing the OLED were purified by vacuum sublimation at 10−6 Torr.
OLEDs were produced in the same manner as in Device Example 4, except that the hole transport layer, the host material of the light-emitting layer, and the electron buffer layer were made of light hydrogen material.
Table 4 below shows the current efficiency at a luminance of 1,000 nit CIE color coordinates and time taken for luminance to reduce from 100% to 97% at a luminance of 10,000 nit according to CIE color coordinates (lifetime: T97) for the OLEDs of Device Examples 4 and 5 and Comparative Examples 4 and 5 produced as described above.
Comparative Example 4
Device Example 5
Comparative Example 5
From Table 4 above, it can be confirmed that the organic electroluminescent device according to the present disclosure exhibits higher current efficiency and much higher lifetime compared to a conventional organic electroluminescent device.
An OLED according to the present disclosure was produced. First, a transparent electrode indium tin oxide (ITO) thin film (10 Ω/sq) on a glass substrate for an OLED (GEOMATEC CO., LTD., Japan) was subjected to an ultrasonic washing with acetone and isopropyl alcohol, sequentially, and was then stored in isopropyl alcohol. The ITO substrate was mounted on a substrate holder of a vacuum vapor deposition apparatus. Compound HI (p-dopant) was introduced into a cell of the vacuum vapor deposition apparatus, and compound HT′-1 was introduced into another cell. The two materials were evaporated at different rates, and compound HI was deposited in a doping amount of 3 wt % based to the total amount of compound HI and compound HT′-1 to form a hole injection layer with a thickness of 10 nm. Subsequently, compound HT′-1 was deposited on the hole injection layer to form a first hole transport layer with a thickness of 80 nm. Next, the compound shown in Table 5 was introduced into another cell of the vacuum vapor deposition apparatus as a second hole transport layer and was evaporated by applying an electric current to the cell, thereby depositing with a thickness of 30 nm. After forming the hole injection layer and the hole transport layers, a light-emitting layer was deposited thereon as follows: the compounds shown in Table 5 below were introduced into a cell of the vacuum vapor deposition apparatus as hosts at a ratio of 2:1, and compound GD was introduced into another cell as a dopant. The materials were evaporated at a different rate, and the dopant was deposited in a doping amount of 10 wt % based on the total amount of the hosts and dopant to form a light-emitting layer with a thickness of 40 nm on the second hole transport layer. The compound shown in Table 5 was deposited with a thickness of 5 nm as an electron buffer layer, and then compound EI-1 and compound Liq were introduced into two other cells and evaporated at a rate of 1:1 to deposit an electron transport layer with a thickness of 35 nm on the light-emitting layer. After introducing compound Liq as an electron injection layer and depositing with a thickness of 2 nm on the electron transport layer, an Al cathode was deposited with a thickness of 80 nm by using another vacuum vapor deposition apparatus, thereby producing an OLED. All the materials used for producing the OLED were purified by vacuum sublimation at 10 Torr.
An OLED was produced in the same manner as in Device Example 6, except that the hole transport layer, the host material of the light-emitting layer, and the electron buffer layer were made of light hydrogen material.
Table 5 below shows the current efficiency at a luminance of 1,000 nit and time taken for luminance to reduce from 100% to 95% at a luminance of 1,000 nit (lifetime: T95) for the OLEDs of Device Example 6 and Comparative Example 6 produced as described above.
Comparative Example 6
From Table 5 above, it can be confirmed that the organic electroluminescent device according to the present disclosure exhibits higher lifetime while maintaining current efficiency compared to a conventional organic electroluminescent device.
The compounds used in the above Device Examples and Comparative Examples are shown in Table 6 below.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2023-0178599 | Dec 2023 | KR | national |
| 10-2024-0120902 | Sep 2024 | KR | national |
