Organic Electronic Device Comprising a Compound of Formula (I), Display Device Comprising the Organic Electronic Device as Well as Compounds of Formula (I) for Use in Organic Electronic Devices

Abstract

The present invention relates to a compound of formula (I) and an organic electronic device comprising a semiconductor layer which comprises a compound of formula (I).

##STR00001##

Claims

1. An organic electronic device comprising a substrate, an anode layer, a cathode layer, at least one first emission layer, and a hole injection layer, wherein the hole injection layer is arranged between the first emission layer and the anode layer, and whereby the hole injection layer comprises a compound of formula (I) ##STR00267## whereby A.sup.1 is selected from formula (II) ##STR00268## X.sup.1 is selected from CR.sup.1 or N; X.sup.2 is selected from CR.sup.2 or N; X.sup.3 is selected from CR.sup.3 or N; X.sup.4 is selected from CR.sup.4 or N; X.sup.5 is selected from CR.sup.5 or N; R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 (if present) are independently selected from CN, partially fluorinated or perfluorinated C.sub.1 to C.sub.8 alkyl, halogen, Cl, F, D or H, whereby when any of R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 is present, then the corresponding X.sup.1, X.sup.2, X.sup.3, X.sup.4 and X.sup.5 is not N; with the proviso that one of the following requirements a) to e) are fulfilled: a) At least one R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 is independently selected from CN, partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl, halogen, Cl, F, and at least one remaining R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 is selected D or H; b) R.sup.1 or R.sup.2 are selected from CN or partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl and at least one remaining R.sup.1 to R.sup.5 is independently selected from CN, partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl, halogen, C.sub.1 or F; c) R.sup.3 is selected from partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl and at least one of R.sup.1, R.sup.2, R.sup.4 and R.sup.5 is independently selected from CN, partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl, halogen, C.sub.1 or F; d) at least two R.sup.1 to R.sup.5 are independently selected from CN or partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl; or e) at least one X.sup.1 to X.sup.5 is N and at least two X.sup.1 to X.sup.5 are selected from CR.sup.1 to CR.sup.5; A.sup.2 and A.sup.3 are independently selected from formula (III) ##STR00269## wherein Ar is independently selected from substituted or unsubstituted C.sub.6 to C.sub.18 aryl and substituted or unsubstituted C.sub.2 to Cis heteroaryl, wherein the substituents on Ar are independently selected from CN, partially or perfluorinated C.sub.1 to C.sub.6 alkyl, halogen, Cl, F, D; and R.sup.1 is selected from Ar, substituted or unsubstituted C.sub.6 to C.sub.18 aryl or C.sub.3 to C.sub.18 heteroaryl, partially flurorinated or perfluorinated C.sub.1 to C.sub.8 alkyl, halogen, F or CN; and whereby the anode layer comprises a first anode sub-layer and a second anode sub-layer, wherein the first anode sub-layer comprises a first metal having a work function in the range of ≥4 and ≤6 eV, and the second anode sub-layer comprises a transparent conductive oxide; and the second anode sub-layer is arranged closer to the hole injection layer.

2. The organic electronic device of claim 1, whereby the wherein the first metal of the first anode sub-layer is selected from the group comprising Ag, Mg, Al, Cr, Pt, Au, Pd, Ni, Nd, Ir.

3. The organic electronic device of claim 1, wherein the anode layer of the organic electronic device comprises in addition a third anode sub-layer comprising a transparent conductive oxide, wherein the third anode sub-layer is arranged between the substrate and the first anode sub-layer

4. The organic electronic device of any of the claim 1, whereby the transparent conductive oxide is selected from the group comprising indium tin oxide or indium zinc oxide, more preferred indium tin oxide.

5. The organic electronic device of claim 1, whereby the hole injection layer comprises a compound of formula (IV) ##STR00270## whereby B.sup.1 is selected from formula (V) ##STR00271## B.sup.3 and B.sup.5 are Ar and B.sup.2, B.sup.4 and B.sup.6 are R.sup.1.

6. The organic electronic device of claim 1, whereby at least two of the requirements a) to e) are fulfilled.

7. The organic electronic device of claim 1, whereby A.sup.2 and A.sup.3 are identical.

8. The organic electronic device of claim 1, whereby A.sup.1 differs from A.sup.2 and A.sup.3.

9. The organic electronic device of claim 1, whereby the hole injection layer comprises a composition comprising a compound of formula (IV) and at least one compound of formula (IVa) to (IVd) ##STR00272##

10. The organic electronic device of claim 1, wherein LUMO level of compound of formula (I) is selected in the range of ≤−4.3 eV and ≥−5.6 eV.

11. The organic electronic device of claim 1, wherein the hole injection layer comprises a substantially covalent matrix compound with a molecular weight Mw of ≥400 and ≤2000 g/mol.

12. The organic electronic device of claim 1, whereby the substantially covalent matrix compound comprises at least one arylamine compound, diarylamine compound, triarylamine compound, a compound of formula (II) or a compound of formula (III): ##STR00273## wherein: T.sup.1, T.sup.2, T.sup.3, T.sup.4 and T.sup.5 are independently selected from a single bond, phenylene, biphenylene, terphenylene or naphthenylene, T.sup.6 is phenylene, biphenylene, terphenylene or naphthenylene; Ar.sup.1, Ar.sup.2, Ar.sup.3, Ar.sup.4 and Ar.sup.5 are independently selected from substituted or unsubstituted C.sub.6 to C.sub.20 aryl, or substituted or unsubstituted C.sub.3 to C.sub.20 heteroarylene, substituted or unsubstituted biphenylene, substituted or unsubstituted fluorene, substituted 9-fluorene, substituted 9,9-fluorene, substituted or unsubstituted naphthalene, substituted or unsubstituted anthracene, substituted or unsubstituted phenanthrene, substituted or unsubstituted pyrene, substituted or unsubstituted perylene, substituted or unsubstituted triphenylene, substituted or unsubstituted tetracene, substituted or unsubstituted tetraphene, substituted or unsubstituted dibenzofurane, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted xanthene, substituted or unsubstituted carbazole, substituted 9-phenylcarbazole, substituted or unsubstituted azepine, substituted or unsubstituted dibenzo[b,f]azepine, substituted or unsubstituted 9,9′-spirobi[fluorene], substituted or unsubstituted spiro[fluorene-9,9′-xanthene], or a substituted or unsubstituted aromatic fused ring system comprising at least three substituted or unsubstituted aromatic rings selected from the group comprising substituted or unsubstituted non-hetero, substituted or unsubstituted hetero 5-member rings, substituted or unsubstituted 6-member rings and/or substituted or unsubstituted 7-member rings, substituted or unsubstituted fluorene, or a fused ring system comprising 2 to 6 substituted or unsubstituted 5- to 7-member rings and the rings are selected from the group comprising (i) unsaturated 5- to 7-member ring of a heterocycle, (ii) 5- to 6-member of an aromatic heterocycle, (iii) unsaturated 5- to 7-member ring of a non-heterocycle, (iv) 6-member ring of an aromatic non-heterocycle; wherein the substituents of Ar.sup.1, Ar.sup.2, Ar.sup.3, Ar.sup.4 and Ar.sup.5 are selected the same or different from the group comprising H, D, F, C(—O)R.sup.2, CN, Si(R.sup.2).sub.3, P(—O)(R.sup.2).sub.2, OR.sup.2, S(—O)R.sup.2, S(—O).sub.2R.sup.2, substituted or unsubstituted straight-chain alkyl having 1 to 20 carbon atoms, substituted or unsubstituted branched alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cyclic alkyl having 3 to 20 carbon atoms, substituted or unsubstituted alkenyl or alkynyl groups having 2 to 20 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aromatic ring systems having 6 to 40 aromatic ring atoms, and substituted or unsubstituted heteroaromatic ring systems having 5 to 40 aromatic ring atoms, unsubstituted C.sub.6 to C.sub.18 aryl, unsubstituted C.sub.3 to C.sub.18 heteroaryl, a fused ring system comprising 2 to 6 unsubstituted 5- to 7-member rings and the rings are selected from the group comprising unsaturated 5- to 7-member ring of a heterocycle, 5- to 6-member of an aromatic heterocycle, unsaturated 5- to 7-member ring of a non-heterocycle, and 6-member ring of an aromatic non-heterocycle, wherein R.sup.2 is selected from H, D, straight-chain alkyl having 1 to 6 carbon atoms, branched alkyl having 1 to 6 carbon atoms, cyclic alkyl having 3 to 6 carbon atoms, alkenyl or alkynyl groups having 2 to 6 carbon atoms, C.sub.6 to C.sub.18 aryl or C.sub.3 to C.sub.18 heteroaryl.

13. The organic electronic device of claim 1, whereby the organic electronic device comprises a hole transport layer, wherein the hole transport layer is arranged between the hole injection layer and the at least one first emission layer and the hole transport layer comprises a substantially covalent matrix compound.

14. A display device comprising an organic electronic device according to claim 1.

15. A compound of formula (I) of claim 1, wherein formula (III) is selected from the group consisting of: ##STR00274##

Description

[0245] FIGS. 1 to 6

[0246] FIG. 1 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0247] FIG. 2 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0248] FIG. 3 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention.

[0249] FIG. 4 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0250] FIG. 5 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0251] FIG. 6 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0252] Hereinafter, the FIGS. 1 to 6 are illustrated in more detail with reference to examples. However, the present disclosure is not limited to the following figures.

[0253] 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.

[0254] FIG. 1 is a schematic sectional view of an organic electronic device (100), according to an exemplary embodiment of the present invention. The organic electronic device (100) includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121) and a second anode sub-layer (122) and a hole injection layer (HIL) (130). The HIL (130) is disposed on the anode layer (120). Onto the HIL (130), a first emission layer (EML) (150), and a cathode layer (190) are disposed.

[0255] FIG. 2 is a schematic sectional view of an organic electronic device (100), according to an exemplary embodiment of the present invention. The organic electronic device (100) includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121), a second anode sub-layer (122) and a third anode sub-layer (123), and a hole injection layer (HIL) (130). The HIL (130) is disposed on the anode layer (120) comprising a first anode sub-layer (121), a second anode sub-layer (122) and a third anode sub-layer (123). Onto the HIL (130), a first emission layer (EML) (150), and a cathode layer (190) are disposed.

[0256] FIG. 3 is a schematic sectional view of an organic electronic device (100), according to an exemplary embodiment of the present invention. The organic electronic device (100) includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121) and a second anode sub-layer (122), and a hole injection layer (HIL) (130). The HIL (130) is disposed on the anode layer (120). Onto the HIL (130), an hole transport layer (HTL) (140), a first emission layer (EML) (150), a hole blocking layer (BL) (155), an electron transport layer (ETL) (160), and a cathode layer (190) are disposed.

[0257] FIG. 4 is a schematic sectional view of an organic electronic device (100), according to an exemplary embodiment of the present invention. The organic electronic device (100) includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121), a second anode sub-layer (122) and a third anode sub-layer (123), and a hole injection layer (HIL) (130). The HIL (130) is disposed on the anode layer (120). Onto the HIL (130), an hole transport layer

[0258] (HTL) (140), a first emission layer (EML) (150), a hole blocking layer (HBL) (155), an electron transport layer (ETL) (160), and a cathode layer (190) are disposed.

[0259] FIG. 5 is a schematic sectional view of an organic electronic device (100), according to an exemplary embodiment of the present invention. The organic electronic device (100) includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121) and a second anode sub-layer (122) and a hole injection layer (HIL) (130). The HIL (130) is disposed on the anode layer (120). Onto the HIL (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), a first emission layer (EML) (150), a hole blocking layer (HBL) (155), an electron transport layer (ETL) (160), and a cathode layer (190) are disposed.

[0260] FIG. 6 is a schematic sectional view of an organic electronic device (100), according to an exemplary embodiment of the present invention. The organic electronic device (100) includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121), a second anode sub-layer (122) and a third anode sub-layer (123), and a hole injection layer (HIL) (130). The HIL (130) is disposed on the anode layer (120). Onto the HIL (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), a first emission layer (EML) (150), a hole blocking layer (HBL) (155), an electron transport layer (ETL) (160), an electron injection layer (EIL) (180) and a cathode layer (190) are disposed.

[0261] While not shown in FIG. 1 to FIG. 6, a capping and/or a sealing layer may further be formed on the cathode layer 190, in order to seal the organic electronic device 100. In addition, various other modifications may be applied thereto.

[0262] 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.

DETAILED DESCRIPTION

[0263] The invention is furthermore illustrated by the following examples which are illustrative only and non-binding.

[0264] Compounds of formula (I) may be prepared as described in EP2180029A1 and

Calculated HOMO and LUMO

[0265] The HOMO and LUMO are calculated with the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany). The optimized geometries and the HOMO and LUMO energy levels of the molecular structures are determined by applying the hybrid functional B3LYP with a 6-31G* basis set in the gas phase. If more than one conformation is viable, the conformation with the lowest total energy is selected.

General Procedure for Fabrication of OLEDs

[0266] For Examples 1 to 16 and comparative example 2 in Table 2, a glass substrate with an anode layer comprising a first anode sub-layer of 120 nm Ag, a second anode sub-layer of 8 nm ITO and a third anode sub-layer of 10 nm ITO was cut to a size of 50 mm×50 mm×0.7 mm, ultrasonically washed with water for 60 minutes and then with isopropanol for 20 minutes. The liquid film was removed in a nitrogen stream, followed by plasma treatment, see Table 2, to prepare the anode layer. The plasma treatment was performed in nitrogen atmosphere or in an atmosphere comprising 97.6 vol.-% nitrogen and 2.4 vol.-% oxygen.

[0267] Then, compound of formula F3 as matrix compound and compound of formula (I) were co-deposited in vacuum on the anode layer, to form a hole injection layer (HIL) having a thickness of 10 nm. The percentage compound of formula (I) in the HIL can be seen in Table 2.

[0268] Then, compound of formula F3 was vacuum deposited on the HIL, to form a HTL having a thickness of 123 nm.

[0269] Then N-([1,1′-biphenyl]-4-yl)-9,9-diphenyl-N-(4-(triphenylsilyl)phenyl)-9H-fluoren-2-amine (CAS 1613079-70-1) was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0270] Then 97 vol.-% H09 (Sun Fine Chemicals, Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue emitter dopant were deposited on the EBL, to form a blue-emitting first emission layer (EML) with a thickness of 20 nm.

[0271] Then a hole blocking layer was formed with a thickness of 5 nm by depositing 2-(3′-(9,9-dimethyl-9H-fluoren-2-yl)[1,1′-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine on the emission layer EML.

[0272] Then the electron transporting layer having a thickness of 31 nm was formed on the hole blocking layer by depositing 50 wt. -% 4′-(4-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)naphthalen-1-yl)-[1,1′-biphenyl]-4-carbonitrile and 50 wt. -% of LiQ.

[0273] Then Ag:Mg (90:10 vol.-%) was evaporated at a rate of 0.01 to 1 Å/s at 10.sup.−7 mbar to form a cathode layer with a thickness of 13 nm on the electron transporting layer.

[0274] Then, compound of formula F3 was deposited on the cathode layer to form a capping layer with a thickness of 75 nm.

Comparative Example 1

[0275] For comparative example 1 in Table 3, a 15Ω/cm.sup.2 glass substrate with 90 nm ITO (available from Corning Co.) was cut to a size of 50 mm×50 mm×0.7 mm, ultrasonically washed with water for 60 minutes and then with isopropanol for 20 minutes. The liquid film was removed in a nitrogen stream, followed by plasma treatment in nitrogen atmosphere at a power of 100 W for 75 seconds to prepare the anode layer.

[0276] Then, 92 wt.-% compound of formula F3 and 8 wt.-% compound A8 were co-deposited in vacuum on the anode layer, to form a hole injection layer (HIL) having a thickness of 10 nm.

[0277] Then, compound of formula F3 was vacuum deposited on the HIL, to form a HTL having a thickness of 123 nm.

[0278] Then, the EBL, EML, HBL and ETL are deposited in this order on the HTL, as described for example 1 above.

[0279] Then Yb was evaporated at a rate of 0.01 to 1 Å/s at 10.sup.−7 mbar to form an electron injection layer with a thickness of 2 nm on the electron transporting layer.

[0280] Then A1 was evaporated at a rate of 0.01 to 1 Å/s at 10.sup.−7 mbar to form a cathode layer with a thickness of 100 nm on the electron injection layer.

[0281] 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.

[0282] To assess the performance of the inventive examples compared to the prior art, the current efficiency is measured at 20° C. The current-voltage characteristic is determined using a Keithley 2635 source measure unit, by sourcing an operating voltage U 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 0 V and 10 V.

Technical Effect of the Invention

[0283] In Table 1 are shown LUMO levels for Examples A1 to A37 and comparative example 1 (═C.sub.1). As comparative compound (referred to as C.sub.1) a compound with A.sup.1 to A.sup.3=Phenyl and R′ ═CN was used.

[0284] LUMO levels were calculated with the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany) by applying the hybrid functional B3LYP with a 6-31G* basis set in the gas phase.

TABLE-US-00002 TABLE 1 Calculated LUMO level of compounds of formula (I) A.sup.1 A.sup.2 A.sup.3 LUMO [eV] C1 [00153] [00154] [00155] −3.81 A1 [00156] [00157] [00158] −4.34 A2 [00159] [00160] [00161] −4.39 A3 [00162] [00163] [00164] −4.44 A4 [00165] [00166] [00167] −4.75 A5 [00168] [00169] [00170] −4.58 A6 [00171] [00172] [00173] −4.85 A7 [00174] [00175] [00176] −4.75 A8 [00177] [00178] [00179] −4.82 A9 [00180] [00181] [00182] −4.83 A10 [00183] [00184] [00185] −4.92 A11 [00186] [00187] [00188] −4.95 A12 [00189] [00190] [00191] −4.99 A13 [00192] [00193] [00194] −5.12 A14 [00195] [00196] [00197] −5.16 A15 [00198] [00199] [00200] −5.09 A16 [00201] [00202] [00203] −5.07 A17 [00204] [00205] [00206] −4.73 A18 [00207] [00208] [00209] −4.91 A19 [00210] [00211] [00212] −4.71 A20 [00213] [00214] [00215] −5.07 A21 [00216] [00217] [00218] −4.71 A22 [00219] [00220] [00221] −5.50 A23 [00222] [00223] [00224] −4.95 A24 [00225] [00226] [00227] −4.52 A25 [00228] [00229] [00230] −4.92 A26 [00231] [00232] [00233] −4.82 A27 [00234] [00235] [00236] −5.07 A28 [00237] [00238] [00239] −4.93 A29 [00240] [00241] [00242] −5.03 A30 [00243] [00244] [00245] −4.66 A31 [00246] [00247] [00248] −4.95 A32 [00249] [00250] [00251] −5.33 A33 [00252] [00253] [00254] −5.58 A34 [00255] [00256] [00257] −5.36 A35 [00258] [00259] [00260] −5.50 A36 [00261] [00262] [00263] −4.96 A37 [00264] [00265] [00266] −5.61

[0285] Table 2 shows the setup and the operating voltage of one device according to comparative examples 1 and 2 and to examples 1 to 16 according to the invention:

TABLE-US-00003 Percentage compound of U at 50 Compound of formula (I) mA/cm.sup.2 Anode formula (I) [vol.-%] [V] Comparative ITO A8 8 4.23 example 1 Comparative ITO/Ag/ITO C1 8 4.9 example 2 Example 1 ITO/Ag/ITO A8 8 3.84 Example 2 ITO/Ag/ITO A8 12 3.83 Example 3 ITO/Ag/ITO A8 15 3.82 Example 4 ITO/Ag/ITO A10 8 3.83 Example 5 ITO/Ag/ITO A26 8 3.85 Example 6 ITO/Ag/ITO A26 15 3.83 Example 7 ITO/Ag/ITO A4 8 3.87 Example 8 ITO/Ag/ITO A11 8 3.84 Example 9 ITO/Ag/ITO A24 8 3.86 Example 10 ITO/Ag/ITO A14 8 3.79 Example 11 ITO/Ag/ITO A16 8 3.8 Example 12 ITO/Ag/ITO A18 8 3.82 Example 13 ITO/Ag/ITO A20 8 3.81 Example 14 ITO/Ag/ITO A29 8 3.82 Example 15 ITO/Ag/ITO A31 8 3.83 Example 16 ITO/Ag/ITO A36 8 3.84

[0286] A low operating voltage U may be beneficial for reduced power consumption and improved battery life, in particular in mobile devices.

[0287] The particular combinations of elements and features in the above detailed embodiments are exemplary only; the interchanging and substitution of these teachings with other teachings in this and the patents/applications incorporated by reference are also expressly contemplated. As those skilled in the art will recognize, variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the foregoing description is by way of example only and is not intended as limiting. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. The invention's scope is defined in the following claims and the equivalents thereto. Furthermore, reference signs used in the description and claims do not limit the scope of the invention as claimed.