Organic Electronic Device, Display and LIghting Devices Comprising the Same
20210036231 ยท 2021-02-04
Inventors
Cpc classification
H10K85/625
ELECTRICITY
C07D213/06
CHEMISTRY; METALLURGY
H10K2101/30
ELECTRICITY
H10K85/6574
ELECTRICITY
H10K2101/40
ELECTRICITY
C07D239/26
CHEMISTRY; METALLURGY
C07C233/65
CHEMISTRY; METALLURGY
H10K30/353
ELECTRICITY
H05B33/14
ELECTRICITY
H10K85/6576
ELECTRICITY
C07D307/77
CHEMISTRY; METALLURGY
C09K2211/1059
CHEMISTRY; METALLURGY
C07C233/64
CHEMISTRY; METALLURGY
C07D215/04
CHEMISTRY; METALLURGY
C07C255/50
CHEMISTRY; METALLURGY
H10K85/626
ELECTRICITY
C07D405/04
CHEMISTRY; METALLURGY
C07D277/66
CHEMISTRY; METALLURGY
H10K99/00
ELECTRICITY
C07D235/18
CHEMISTRY; METALLURGY
C07D333/50
CHEMISTRY; METALLURGY
H10K85/615
ELECTRICITY
International classification
Abstract
The present invention relates to an organic electronic device comprising, between an anode and a cathode, at least one layer selected from an electron injection layer, an electron transport layer or an electron generation layer, the layer comprising at least one compound of the following Formula (I), wherein the compound of Formula (I) comprises one or more moieties -(A).sub.a-L and the remaining positions marked with * are hydrogen or substituents independently selected from the group consisting of deuterium, fluorine, RF, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.1-C.sub.12 linear fluorinated alkyl, CN, RCN, C.sub.6-C.sub.20 aryl, C.sub.2-C.sub.20 heteroaryl, (PO)R.sub.2; wherein each R is independently selected from C.sub.1-C.sub.20 linear alkyl, C.sub.1-C.sub.20 alkoxy, C.sub.1-C.sub.20 thioalkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.3-C.sub.20 branched alkoxy, C.sub.3-C.sub.20 cyclic alkoxy, C.sub.3-C.sub.20 branched thioalkyl, C.sub.3-C.sub.20 cyclic thioalkyl, C.sub.6-C.sub.20 aryl and C.sub.2-C.sub.20 heteroaryl; A is selected from substituted or unsubstituted C.sub.6-C.sub.24 aryl or C.sub.2-C.sub.20 heteroaryl; wherein in case that A is substituted, the respective substituents are independently selected from the group consisting of deuterium, fluorine, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, linear fluorinated C.sub.1-C.sub.12 alkyl, CN, C.sub.6-C.sub.20 aryl, and C.sub.2-C.sub.2 heteroaryl; L is selected from substituted or unsubstituted C.sub.2-C.sub.42 heteroaryl, substituted or unsubstituted C.sub.6-C.sub.24 aryl or a polar group selected from (formula (aa)), (formula (bb)) and (formula (cc)), wherein substituents, if present in the respective group L are independently selected from the group consisting of deuterium, N fluorine, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.1-C.sub.20 linear alkoxy, C.sub.3-C.sub.20 branched alkoxy, C.sub.1-C.sub.12 linear fluorinated alkyl, C.sub.1-C.sub.12 linear fluorinated alkoxy, C.sub.3-C.sub.12 branched fluorinated cyclic alkyl, C.sub.3-C.sub.12 fluorinated cyclic alkyl, C.sub.3-C.sub.12 fluorinated cycle alkoxy, CN, RCN, C.sub.6-C.sub.20 aryl, C.sub.2-C.sub.20 heteroaryl, OR, SR, (CO)R, (CO)NR.sub.2, SiR.sub.3, (SO)R (SO).sub.2R, (PO)R.sub.2; wherein each R independently selected from C.sub.1-C.sub.20 linear alkyl, C.sub.1-C.sub.20 alkoxy, C.sub.1-C.sub.20 thioalkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.3-C.sub.20 branched alkoxy, C.sub.3-C.sub.20 cyclic alkoxy, C.sub.3-C.sub.20 branched thioalkyl, C.sub.3-C.sub.20 cyclic thioalkyl, C.sub.6-C.sub.20 aryl and C.sub.2-C.sub.20 heteroaryl, and a is an integer from 0 to 2, respective compounds as well as display and lightning devices comprising the same.
##STR00001##
Claims
1. Organic electronic device comprising, between an anode and a cathode, at least one layer selected from an electron injection layer, an electron transport layer or an electron generation layer, the layer comprising at least one compound of the following Formula (I): ##STR00108## wherein the compound of Formula (I) comprises one or more moieties -(A).sub.a-L and the remaining positions marked with * are hydrogen or substituents independently selected from the group consisting of deuterium, fluorine, RF, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.1-C.sub.12 linear fluorinated alkyl, CN, RCN, C.sub.6-C.sub.20 aryl, C.sub.2-C.sub.20 heteroaryl, (PO)R.sub.2; wherein each R is independently selected from C.sub.1-C.sub.20 linear alkyl, C.sub.1-C.sub.20 alkoxy, C.sub.1-C.sub.20 thioalkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.3-C.sub.20 branched alkoxy, C.sub.3-C.sub.20 cyclic alkoxy, C.sub.3-C.sub.20 branched thioalkyl, C.sub.3-C.sub.20 cyclic thioalkyl, C.sub.6-C.sub.20 aryl and C.sub.2-C.sub.20 heteroaryl; A is selected from substituted or unsubstituted C.sub.6-C.sub.24 aryl or C.sub.2-C.sub.2 heteroaryl; wherein in case that A is substituted, the respective substituents are independently selected from the group consisting of deuterium, fluorine, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, linear fluorinated C.sub.1-C.sub.12 alkyl, CN, C.sub.6-C.sub.20 aryl, and C.sub.2-C.sub.20 heteroaryl; L is selected from substituted or unsubstituted C.sub.2-C.sub.42 heteroaryl, substituted or unsubstituted C.sub.6-C.sub.24 aryl or a polar group selected from ##STR00109## wherein substituents, if present in the respective group L are independently selected from the group consisting of deuterium, fluorine, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.1-C.sub.20 linear alkoxy, C.sub.3-C.sub.20 branched alkoxy, C.sub.1-C.sub.12 linear fluorinated alkyl, C.sub.1-C.sub.12 linear fluorinated alkoxy, C.sub.3-C.sub.12 branched fluorinated cyclic alkyl, C.sub.3-C.sub.12 fluorinated cyclic alkyl, C.sub.3-C.sub.12 fluorinated cyclic alkoxy, CN, RCN, C.sub.6-C.sub.20 aryl, C.sub.2-C.sub.20 heteroaryl, OR, SR, (CO)R, (CO)NR.sub.2, SiR.sub.3, (SO)R, (SO).sub.2R, (PO)R.sub.2; wherein each R independently selected from C.sub.1-C.sub.20 linear alkyl, C.sub.1-C.sub.2 alkoxy, C.sub.1-C.sub.20 thioalkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.3-C.sub.20 branched alkoxy, C.sub.3-C.sub.20 cyclic alkoxy, C.sub.3-C.sub.20 branched thioalkyl, C.sub.3-C.sub.20 cyclic thioalkyl, C.sub.6-C.sub.20 aryl and C.sub.2-C.sub.20 heteroaryl, and a is an integer from 0 to 2.
2. Organic electronic device according to claim 1, wherein A is unsubstituted.
3. Organic electronic device according to claim 1, wherein in case that L is substituted, the respective substituents are independently selected from the group consisting of phenyl, naphthyl, pyridyl, bi-phenylyl, dibenzofuranyl, dibenzothiophenyl and carbazolyl.
4. Organic electronic device according to claim 1, wherein in case that L is C.sub.2-C.sub.42 heteroaryl, the C.sub.2-C.sub.42 heteroaryl is selected from the group consisting of triazine, pyrimidine, benzoacridine, dibenzoacridine, pyridine, bi-pyridine, benzimidazole, phenanthroline, benzo-nitrile, phenanthridine, benzooxazole, benzothiazole, phenanthridine-one, naphto-benzofurane, di-naphtofurane, benzo-naphto-thiophene and dinaphtothiophene.
5. Organic electronic device according to claim 4, wherein the C.sub.2-C.sub.42 heteroaryl is selected from the group consisting of triazine, pyrimidine, benzoacridine and dibenzoacridine.
6. Organic electronic device according to claim 1, wherein in case that L is C.sub.6-C.sub.24 aryl, the C.sub.6-C.sub.24 aryl is selected from the group consisting of anthracene, phenanthrene, pyrene, fluoranthene and triphenylene.
7. Organic electronic device according to claim 1, wherein, in case that L is substituted, the substituents are independently selected from the group consisting of ##STR00110## ##STR00111##
8. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) consists of at least one compound of Formula (I).
9. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) further comprises a metal, metal salt or organic metal complex.
10. Organic semiconducting device according to claim 1, wherein the organic electronic device further comprises an emission layer and the layer comprising the compound of Formula (I) is arranged between the emission layer and the cathode.
11. Organic semiconducting device according to claim 1, further comprising an electron transport layer, wherein the layer comprising the compound of Formula (I) is arranged between the electron transport layer and the cathode.
12. Compound having the general Formula (I) ##STR00112## wherein the compound of Formula (I) comprises one or more moieties -(A).sub.a-L and the remaining positions are hydrogen or substituents independently selected from the group consisting of deuterium, fluorine, RF, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.1-C.sub.12 linear fluorinated alkyl, CN, RCN, C.sub.6-C.sub.20 aryl, C.sub.2-C.sub.20 heteroaryl, (PO)R.sub.2; wherein each R is independently selected from C.sub.1-C.sub.20 linear alkyl, C.sub.1-C.sub.2 alkoxy, C.sub.1-C.sub.20 thioalkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.3-C.sub.20 branched alkoxy, C.sub.3-C.sub.20 cyclic alkoxy, C.sub.3-C.sub.20 branched thioalkyl, C.sub.3-C.sub.20 cyclic thioalkyl, C.sub.6-C.sub.20 aryl and C.sub.2-C.sub.2 heteroaryl; A is selected from substituted or unsubstituted C.sub.6-C.sub.12 aryl or C.sub.2-C.sub.2 heteroaryl; wherein in case that A is substituted, the respective substituents are independently selected from the group consisting of deuterium, fluorine, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, linear fluorinated C.sub.1-C.sub.12 alkyl, CN, C.sub.6-C.sub.20 aryl, and C.sub.2-C.sub.20 heteroaryl; L is selected from substituted or unsubstituted C.sub.2-C.sub.42 heteroaryl, C.sub.6-C.sub.24 aryl or a polar group selected from ##STR00113## wherein substituents, if present in the respective group L are independently selected from the group consisting of deuterium, fluorine, C.sub.1-C.sub.20 linear alkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.1-C.sub.20 linear alkoxy, C.sub.3-C.sub.20 branched alkoxy, C.sub.1-C.sub.12 linear fluorinated alkyl, C.sub.1-C.sub.12 linear fluorinated alkoxy, C.sub.3-C.sub.12 branched fluorinated cyclic alkyl, C.sub.3-C.sub.12 fluorinated cyclic alkyl, C.sub.3-C.sub.12 fluorinated cyclic alkoxy, CN, RCN, C.sub.6-C.sub.20 aryl, C.sub.2-C.sub.20 heteroaryl, OR, SR, (CO)R, (CO)NR.sub.2, SiR.sub.3, (SO)R, (SO).sub.2R, (PO)R.sub.2; wherein each R is independently selected from C.sub.1-C.sub.20 linear alkyl, C.sub.1-C.sub.2 alkoxy, C.sub.1-C.sub.20 thioalkyl, C.sub.3-C.sub.20 branched alkyl, C.sub.3-C.sub.20 cyclic alkyl, C.sub.3-C.sub.20 branched alkoxy, C.sub.3-C.sub.20 cyclic alkoxy, C.sub.3-C.sub.20 branched thioalkyl, C.sub.3-C.sub.20 cyclic thioalkyl, C.sub.6-C.sub.20 aryl and C.sub.2-C.sub.20 heteroaryl; wherein in case that L is a N-containing heteroaryl group, the compound of the Formula (I) does only comprise one *-(A).sub.a-L moiety in which the C.sub.2-C.sub.42 heteroaryl is a N-containing heteroaryl group.
13. Organic semiconducting layer comprising the compound according to claim 12.
14. Display device comprising the organic electronic device according to claim 1.
15. Lighting device comprising the organic electronic device according to claim 1.
16. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) further comprises an alkali metal additive or a rare earth metal additive.
17. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) further comprises a rare earth metal or an alkali metal complex.
18. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) further comprises an alkali metal salt.
19. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) further comprises Yb, LiQ, alkali borate, or alkali phenolate.
20. Organic electronic device according to claim 1, wherein the layer comprising the compound of Formula (I) further comprises LiQ.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0158] These and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings, of which:
[0159]
[0160]
[0161]
DETAILED DESCRIPTION
[0162] Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below, in order to explain the aspects of the present invention, by referring to the figures.
[0163] Herein, when a first element is referred to as being formed or disposed on or onto a second element, the first element can be disposed directly on the second element, or one or more other elements may be disposed there between. When a first element is referred to as being formed or disposed directly on or directly onto a second element, no other elements are disposed there between.
[0164]
[0165] Instead of a single electron transport layer 160, optionally an electron transport layer stack (ETL) can be used.
[0166]
[0167] Referring to
[0168]
[0169] Referring to
[0170] While not shown in
[0171] Hereinafter, one or more exemplary embodiments of the present invention will be described in detail with, reference to the following examples. However, these examples are not intended to limit the purpose and scope of the one or more exemplary embodiments of the present invention.
[0172] The features disclosed in the foregoing description, in the claims and/or in the accompanying drawings may, both separately and in any combination thereof, be material for realizing the invention in diverse forms thereof.
EXPERIMENTAL PART
Experimental Data
Synthesis of Compound of Formula 1
[0173] 2-bromospiro[bienzo[de]anthracene-7,9-fluorene] was synthesized following literature procedure (J.-Y. Kim et al., Dyes and Pigments 2012, 94, 304-313).
##STR00100##
2,4-diphenyl-6-(4-spiro[benzo[de]anthracene-7,9-fluoren]-2-yl)phenyl)-1,3,5-triazine
[0174] ##STR00101##
[0175] A flask was flushed with nitrogen and charged with 2-bromospiro[benzo[de]anthracene-7,9-fluorene] (5.1 g, 11.4 mmol), 2,4-diphenyl-6-(4-(4,4,5,5-tetramethyl-1,3,2-(dioxaborolan-2-yl)phenyl)-1,3,5-triazine (4.9 g, 11.4 mmol), K.sub.2CO.sub.3 (4.7 g, 34.3 mmol), and Pd(PPh.sub.3).sub.4 (0.39 g, 0.3 mmol). A mixture of deaerated 1,4-dioxane/water (6:1, 127 mL) was added and the reaction mixture was heated to 95 C. under a nitrogen atmosphere for 1.5 h. Subsequently, the formed precipitate was collected by suction filtration and washed with 1,4-dioxane. The sold was dissolved in hot chlorobenzene and filtered through a pad of silica gel. The filtrate was concentrated under reduced pressure, and the residue recrystallized from a mixture of chloroform/n-hexane. After drying in vacuo, 4.12 g (53%) of a white solid were obtained. Final purification was achieved by sublimation. HPLC/ESI-MS: 100%, m/z=674 ([M+H].sup.+).
##STR00102##
4,4,5,5-tetramethyl-2-(spiro[benzo[de]anthracene-7,9-fluoren]-2-yl)-1,3,2-dioxaborolane
[0176] ##STR00103##
[0177] A flask was flushed with nitrogen and charged with 2-bromospiro[benzo[de]anthracene-7,9-fluorene] (6.4 g, 14.3 mmol), bis(pinacolato)diboron (4.0 g, 15.0 mmol), potassium acetate (3.5 g, 35.2 mmol), and Pd(dppf)Cl.sub.2 (0.52 g, 0.7 mmol). Deaerated DMF (65 mL) was added and the reaction mixture was heated to 80 C. under a nitrogen atmosphere for 17 h. After cooling down to room temperature the solvent was removed under reduced pressure, the residue was dissolved in dichloromethane and the organic layer washed with water, dried over MgSO.sub.4, and filtered through a pad of Florisil. The filtrate was concentrated under reduced pressure, the residue was triturated with hot n-hexane, and the formed solid was recovered by suction filtration. After drying in vacuuo 5.0 g (70%) of an off-white solid were obtained. HPLC: 99%.
2-(dibenzo[b,d]furan-3-yl)-4-phenyl-6-(spiro[benzo[de]anthracene-7,9-fluoren]-2-yl)-1,3,5-triazine
[0178] ##STR00104##
[0179] A flask was flushed with nitrogen and charged with 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine (3.2 g, 8.9 mmol), 4,4,5,5-tetramethyl-2-(spiro[benzo[de]anthracene-7,9-fluoren]-2-yl)-1,3,2-dioxaborolane (4.8 g, 9.8 mmol),), K.sub.2CO.sub.3 (3.7 g, 26.8 mmol), and Pd(PPh.sub.3).sub.4 (0.31 g, 0.2 mmol). A mixture of deaerated 1,4-dioxane/water (4:1.67 ml) was added and the reaction mixture was heated to 90 C. under a nitrogen atmosphere for 18 h. After cooing down to room temperature the formed precipitate was collected by suction filtration and washed with water and methanol. The solid was dissolved in dichloromethane, and the organic layer was dried over Na.sub.2SO.sub.4 and filtered through a pad of Florisil. The filtrate was concentrated under reduced pressure, the residue was triturated with n-hexane, and the formed solid was recovered by suction filtration, and recrystallized from a mixture of n-hexane/methanol. After drying in vacuo, 3.5 g (57%) of a white solid were obtained. Final purification was achieved by sublimation. HPLC/ESI-MS: 100%, m/z=688 ([M+H].sup.+).
Melting Point
[0180] The melting point (mp) is determined as peak temperatures from the DSC curves of the above TGA-DSC measurement or from separate DSC measurements (Metier Toledo DSC822e, heating of samples from room temperature to completeness of melting with heating rate 10 K/min under a stream of pure nitrogen. Sample amounts of 4 to 6 mg are placed in a 40 L Metier Toledo aluminum pan with lid, a <1 mm hole is pierced into the lid).
Glass Transition Temperature
[0181] The glass transition temperature (Tg) is measured under nitrogen and using a heating rate of 10 K per min in a Metier Toledo DSC 822e differential scanning calorimeter as described in DIN EN ISO 11357, published in March 2010.
Reduction Potential
[0182] The reduction potential is determined by cyclic voltammetry with potentiostatic device Metrohm PGSTAT30 and software Metrohm Autolab GPES at room temperature. The redox potentials given at particular compounds were measured in an argon de-aerated, dry 0.1M THF solution of the tested substance, under argon atmosphere, with 0.1M tetrabutylammonium hexafluorophosphate supporting electrolyte, between platinum working electrodes and with an Ag/AgCl pseudo-standard electrode (Metrohm Silver rod electrode), consisting of a silver wire covered by silver chloride and immersed directly in the measured solution, with the scan rate 100 mV/s. The first run was done in the broadest range of the potential set on the working electrodes, and the range was then adjusted within subsequent runs appropriately. The final three runs were done with the addition of ferrocene (in 0.1M concentration) as the standard. The average of potentials corresponding to cathodic and anodic peak of the studied compound, after subtraction of the average of cathodic and anodic potentials observed for the standard Fc.sup.+/Fc redox couple, afforded finally the values reported above. All studied compounds as well as the reported comparative compounds showed well-defined reversible electrochemical behaviour.
Dipole Moment, LUMO Level, HOMO Level
[0183] The dipole moment || of a molecule containing N atoms is given by:
where q.sub.i and {right arrow over (r.sub.i)} are the partial charge and position of atom i in the molecule.
[0184] The dipole moment is determined by a semi-empirical molecular orbital method.
[0185] The geometries of the molecular structures are optimized using the hybrid functional B3LYP with the 6-31G* basis set as implemented in the program package TURBOMOLE V6.5. If more than one conformation is viable, the conformation with the lowest total energy is selected to determine the bond lengths of the molecules.
[0186] DFT calculations using the program package TURBOMOLE V6.5 are also used in conjunction with the optimized molecular geometries to determine the HOMO and LUMO energy levels of the molecular structures using the hybrid functional B3LYP with a 6-31G* basis set. If more than one conformation is viable, the conformation with the lowest total energy is selected.
Provider; TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany
General Procedure for Fabrication of OLEDs
[0187] For top emission OLED devices, inventive examples and comparative examples, a glass substrate was cut to a size of 50 mm50 mm0.7 mm, ultrasonically cleaned with isopropyl alcohol for 5 minute and then with pure water for 5 minutes, and cleaned again with UV ozone for 30 minutes, to prepare a first electrode. 100 nm Ag were deposited as anode at a pressure of 10.sup.5 to 10.sup.7 mbar to form the anode.
[0188] Then, 92 vol.-% Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) with 8 vol.-% 2,2,2-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) was vacuum deposited on the ITO electrode, to form a HIL having a thickness of 10 nm. Then, Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was vacuum deposited on the HIL, to form a HTL having a thickness of 118 nm.
[0189] Then, N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)-[1,1:4,1-terphenyl]-4-amine (CAS 1198399-61-9) was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.
[0190] Then, the emission layer was deposited. 97 vol.-% H09 (Fluorescent-blue host material, Sun Fine Chemicals) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals) as fluorescent blue dopant were deposited on the EBL, to form a blue-emitting EML with a thickness of 20 nm.
[0191] Then, for top emission OLED devices of configuration A, the hole blocking layer was deposited on the emission layer with a thickness of 5 nm. For example-1 a compound of Formula 1 was deposited on the emission layer, according to table 4. For comparative example-1 the comparative compound-1 was deposited on the emission layer, according to table 4.
[0192] Then, the electron transporting layer is formed on the hole blocking layer with a thickness of 31 nm by co-deposition of 2-([1,1-biphenyl]-4-yl)-4-(9,9-diphenyl-9H-fluoren-4-yl)-6-phenyl-1,3,5-triazine (CAS 1801992-44-8) and lithium quinolate (LiQ) in a wt % ratio of 1:1.
[0193] For top emission OLED devices of configuration B 2,4-diphenyl-6-(4,5,6-triphenyl-[1,1:2,1;3,1:3,1-quinquephenyl]-3-yl)-1,3,5-triazine (CAS 2032364-64-8) was deposited as the hole blocking layer with a thickness of 5 nm on the emission layer. Then, for example-2 and example-3 a compound of Formula 1 was co-deposited with lithium quinolate (LiQ), according to table 5, in a wt % ratio of 1:1 on the emission layer to form the electron transporting layer with a thickness of 31 ran. For comparative example-2 the comparative compound-1 was co-deposited with lithium quinolate (LiQ), according to table 5, in a wt % ratio of 1:1 on the emission layer to form the electron transporting layer with a thickness of 31 nm.
[0194] Then, for both top emission OLED devices of configuration A and B the electron injection layer is formed on the electron transporting layer by deposing Yb with a thickness of 2 nm.
[0195] Ag is evaporated at a rate of 0.01 to 1 /s at 10.sup.7 mbar to form a cathode with a thickness of 11 nm.
[0196] A cap layer of Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine is formed on the cathode with a thickness of 75 nm.
Overview of Compounds Used (Non-Inventive and Non-Comparative)
[0197]
TABLE-US-00002 IUPAC name Reference Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)- US2016322581 [4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) 4,4,4-((1E,1E,1E)-cyclopropane-1,2,3- US2008265216 triylidenetris(cyanomethanylylidene))tris (2,3,5,6-tetrafluorobenzonitrile) N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)- JP2014096418 [1,1:4,1-terphenyl]-4-amine (CAS 1198399-61-9) H09 (Fluorescent-blue host material) Commercially available from Sun Fine Chemicals, Inc, S. Korea BD200 (Fluorescent-blue emitter material) Commercially available from Sun Fine Chemicals, Inc, S. Korea 2,4-diphenyl-6-(4,5,6-triphenyl- WO2016171358 [1,1:2,1:3,1:3,1-quinquephenyl]- 3-yl)-1,3,5-triazine (CAS 2032364-64-8) 2-([1,1-biphenyl]-4-yl)-4-(9,9-diphenyl-9H- KR101537500 fluoren-4-yl)-6-phenyl-1,3,5-triazine (CAS 1801992-44-8) 8-Hydroxyquinolinolato-lithium WO2013079217 (850918-68-2) = LiQ
[0198] The OLED stack is protected from ambient conditions by encapsulation of the device with a glass slide. Thereby, a cavity is formed, which includes a getter material for further protection.
[0199] To assess the performance of the inventive examples compared to the prior art, the current efficiency is measured at 20 C. The current-voltage characteristics are determined using a Keithley 2635 source measure unit by sourcing a voltage in V and measuring the current in mA flowing through the device under test. The voltage applied to the device is varied in steps of 0.1V in the range between 0V and 10V. Likewise, the luminance-voltage characteristics and GE coordinates are determined by measuring the luminance in cd/m.sup.2 using an Instrument Systems CAS-140CT array spectrometer, which has been calibrated by Deutsche Akkreditierungsstelle (DAkkS) for each of the voltage values. The cd/A efficiency at 10 mA/cm.sup.2 is determined by interpolating the luminance-voltage and current-voltage characteristics, respectively.
[0200] In top emission devices, the emission is forward-directed, non-Lambertian and also highly dependent on the micro-cavity. Therefore, the external quantum efficiency (EQE) and power efficiency in lm/W will be higher compared to bottom emission devices.
Technical Effect of the Invention
Material Property
[0201] The Tg values are in a range suitable for use in organic electronic devices. Higher Tg values of materials used in organic electronics are generally preferred for device durability and robustness. The Tg of compound B-1 is significantly increased over file Tg of the comparative compound-1.
[0202] Table 3 shows that the HOMO and LUMO energy levels and the dipole moments of compound B-1 of Formula 1 and of the comparative compound-1. The values are in a range suitable for use as hole blocking materials or electron transporting materials in organic electronic devices.
Top Emission Devices
[0203] Surprisingly, the cd/A (/y) efficiency of top emission OLED devices is increased when using compounds of Formula 1 (instead of the comparative compound) as hole blocking layer. At the same time, the operating voltage of top emission OLED devices is decreased when using compounds of Formula 1 as a hole blocking layer instead of the comparative compound.
[0204] Surprisingly, the lifetime of top emission OLED devices is increased when using compounds of Formula i in an electron transport layer comprising a 1:1 wt % mixture of a compound of Formula 1 and LiQ.
[0205] Table 4 shows the operating voltage and cd/A (/y) efficiencies of top emission OLED devices comprising a hole blocking layer comprising a compound of Formula 1. Table 5 shows the operating voltage and lifetime of top emission OLED devices comprising an electron transport layer comprising a 1:1 wt % mixture of a compound of Formula 1 and LiQ.
[0206] In summary, improved performance of top emission OLED devices can be achieved by using compounds of Formula 1.
Experimental Data (Overview)
[0207]
TABLE-US-00003 TABLE 1 Properties of comparative compounds Compound Tg Tm TRO name Structure ( C) ( C) ( C) Comparative compound-1
TABLE-US-00004 TABLE 2 Properties of compounds of Formula 1 Compound of Tg Tm TRO Formula 1 Structure ( C) ( C) ( C) Compound B-1
TABLE-US-00005 TABLE 3 Energy levels and dipole moments of comparative compound and compounds of Formula 1 Compound Dipole moment name HOMO (eV) * LUMO (eV) * (Debye) * Comparative 5.81 1.89 0.64 compound-1 Compound B-1 5.37 1.88 0.72 Compound B-2 5.36 1.92 0.14 * Values calculated with B3LYP_Gaussian/6-31G*, gas phase
TABLE-US-00006 TABLE 4 Operating voltage of top emission organic electroluminescent devices comprising a compound of Formula 1 in the hole blocking layer (configuration A). Thickness Material hole Operating of Hole blocking voltage Ceff/CIEy blocking layer (V) at (cd/A/y) layer (nm) CIEy 10 mA/cm.sup.2 at 0.045 Comparative Comparative 5 0.045 3.83 131 example 1 compound 1 Example 1 Compound B-1 5 0.038 3.74 137
TABLE-US-00007 TABLE 5 Operating voltage of top emission organic electroluminescent devices comprising a 1:1 wt % mixture of compound of Formula 1 with LiQ in the electron transport layer (configuration B). Material Mixing Thickness electron Operating Lifetime of electron ratio transport voltage at (97%) transport (wt-%) with layer 10 mA/cm.sup.2 (hours) at layer LiQ (nm) CIEy (V) 30mA/cm2 Comparative Comparative 1:1 31 0.044 3.47 29 example 2 compound 1 Example 2 Compound B-1 1:1 31 0.046 3.45 46 Example 3 Compound B-2 1:1 31 0.046 3.41 51