ORGANIC COMPOUND OF FORMULA (I) FOR USE IN ORGANIC ELECTRONIC DEVICES, AN ORGANIC ELECTRONIC DEVICE COMPRISING A COMPOUND OF FORMULA (I) AND A DISPLAY DEVICE COMPRISING THE ORGANIC ELECTRONIC DEVICE

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).

Claims

1. A compound of formula (I) ##STR00205## wherein A.sup.1, A.sup.2 and A.sup.3 are represented by formula (II), (III), (IV), respectively ##STR00206## whereby Ar.sup.1, Ar.sup.2 and Ar.sup.3 are independently selected from substituted or unsubstituted aryl, substituted or unsubstituted C.sub.6 to C.sub.24 aryl, substituted or unsubstituted heteroaryl or C.sub.2 to C.sub.24 heteroaryl, wherein the substituents on Ar.sup.1, Ar.sup.2 and Ar.sup.3 are independently selected form an electron-withdrawing group, NO.sub.2, CN, halogen, Cl, F, partially fluorinated or perfluorinated alkyl and partially fluorinated or perfluorinated C.sub.1 to C.sub.12 alkyl, partially fluorinated or perfluorinated alkoxy, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkoxy or D; R, R and R are independently selected from substituted or unsubstituted aryl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl, electron-withdrawing group, partially fluorinated or perfluorinated alkyl, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkyl, halogen, F, CN, and NO.sub.2; wherein the compound of formula (I) contains at least one NO.sub.2 group; or a salt of a radical anion of formula (I).

2. The compound of claim 1, whereby Ar.sup.1 is substituted with at least one NO.sub.2 group,

3. The compound of claim 1, whereby Ar.sup.1 is represented by formula (V) ##STR00207## wherein 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; wherein one of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 is NO.sub.2 and the other R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are independently selected from electron-withdrawing group, NO.sub.2, CN, halogen, Cl, F, partially fluorinated or perfluorinated alkyl, partially fluorinated or perfluorinated C.sub.1 to C.sub.10 alkyl, partially fluorinated or perfluorinated alkoxy, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkoxy, D or H; wherein at least two of X.sup.1 to X.sup.5 are independently selected from CR.sup.1 to CR.sup.5; and wherein the asterix * denotes the binding position.

4. The compound of claim 3, whereby R.sup.3 is NO.sub.2.

5. The compound of claim 1, selected of the formula (VI) ##STR00208##

6. The compound of claim 1, whereby at least one Ar.sup.2 and Ar.sup.3 is substituted with at least one NO.sub.2.

7. The compound of claim 1, whereby at least one of Ar.sup.2 and Ar.sup.3 does not contain hydrogen.

8. The compound of claim 1, whereby Ar.sup.2 and Ar.sup.3 are identical.

9. The compound of claim 1, whereby Ar.sup.2 is represented by formula (VI) and Ar.sup.3 is represented by formula (VII) ##STR00209## wherein X.sup.6 is selected from CR.sup.6 or N; X.sup.7 is selected from CR.sup.7 or N; X.sup.8 is selected from CR.sup.8 or N; X.sup.9 is selected from CR.sup.9 or N; X.sup.10 is selected from CR.sup.11 or N; wherein X.sup.11 is selected from CR.sup.11 or N; X.sup.12 is selected from CR.sup.12 or N; X.sup.13 is selected from CR.sup.13 or N; X.sup.14 is selected from CR.sup.14 or N; X.sup.15 is selected from CR.sup.15 or N; wherein R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, R.sup.13, R.sup.14, and R.sup.15 are independently selected from electron-withdrawing group, NO.sub.2, CN, halogen, Cl, F, partially fluorinated or perfluorinated alkyl, partially fluorinated or perfluorinated C.sub.1 to C.sub.10 alkyl, partially fluorinated or perfluorinated alkoxy, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkoxy, D or H; wherein at least two of X.sup.6 to X.sup.10 are independently selected from CR.sup.6 to CR.sup.10; wherein at least two of X.sup.11 to X.sup.15 are independently selected from CR.sup.11 to CR.sup.15; and wherein the asterix * denotes the binding position.

10. The compound of claim 1, with the proviso that the following compound of formula (I) is excluded: ##STR00210## wherein X is NO.sub.2 and Y is H.

11. The compound of claim 1, whereby R is selected from substituted or unsubstituted heteroaryl, substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl, electron-withdrawing group, partially fluorinated or perfluorinated alkyl, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkyl, halogen, F, CN, and NO.sub.2.

12. The compound of claim 1, whereby R is selected from partially fluorinated or perfluorinated alkyl, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkyl, halogen, F, CN, and NO.sub.2.

13. The compound of claim 1, whereby R, R and R are independently selected from substituted or unsubstituted heteroaryl, substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl, electron-withdrawing group, partially fluorinated or perfluorinated alkyl, partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkyl, halogen, F, CN, and NO.sub.2.

14. The compound of claim 1, whereby R, R and R are independently selected from partially fluorinated or perfluorinated C.sub.1 to C.sub.6 alkyl, halogen, F, CN, and NO.sub.2.

15. The compound of claim 1, whereby A.sup.1, A.sup.2 and A.sup.3 are represented by formula (IIa), (IIIa) and (IVa), respectively ##STR00211##

16. The compound of any of the claims 1 to 15, whereby the compound of formula (I) contains less than four nitro groups.

17. An organic semiconductor layer comprising at least one compound of formula (I) according to any of claims 1 to 16.

18. An organic electronic device comprising at least one organic semiconductor layer of claim 17.

19. The organic electronic device of claim 18, whereby the organic electronic device comprises an anode layer, a cathode layer, at least one photoactive layer and at least one organic semiconductor layer, wherein the at least one organic semiconductor layer is arranged between the anode layer and at least one photoactive layer

20. The organic electronic device of claim 18, whereby the organic electronic device comprises at least two photoactive layers, wherein at least one organic semiconductor layer is arranged between the first and the second photoactive layer.

21. The organic electronic device of claim 18, whereby the electronic organic device is a light emitting device, a thin film transistor, a battery, a display device or a photovoltaic cell, or an organic light emitting diode.

22. A display device comprising an organic electronic device according to any of the claims 18 to 21.

Description

DESCRIPTION OF THE DRAWINGS

[0329] The aforementioned components, as well as the claimed components and the components to be used in accordance with the invention in the described embodiments, are not subject to any special exceptions with respect to their size, shape, material selection and technical concept such that the selection criteria known in the pertinent field can be applied without limitations.

[0330] Additional details, characteristics and advantages of the object of the invention are disclosed in the dependent claims and the following description of the respective figures which in an exemplary fashion show preferred embodiments according to the invention. Any embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide further explanation of the present invention as claimed.

[0331] FIG. 1 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0332] FIG. 2 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention;

[0333] FIG. 3 is a schematic sectional view of an OLED, according to an exemplary embodiment of the present invention.

[0334] FIG. 4 is a schematic sectional view of a tandem OLED comprising a charge generation layer, according to an exemplary embodiment of the present invention.

[0335] FIG. 5 is a schematic sectional view of a tandem OLED comprising a charge generation layer, according to an exemplary embodiment of the present invention.

[0336] FIG. 6 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention.

[0337] FIG. 7 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention.

[0338] Hereinafter, the figures are illustrated in more detail with reference to examples. However, the present disclosure is not limited to the following figures.

[0339] 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.

[0340] 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 and a hole injection layer (HIL) (130) which may comprise a compound of formula (I). The HIL 130 is disposed on the anode layer 120. Onto the HIL 130, a photoactive layer (PAL) 150 which may be light-emitting layer and a cathode layer 190 are disposed.

[0341] FIG. 2 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate 110, an anode layer 120 and a hole injection layer (HIL) 130 which may comprise a compound of formula (I). The HIL 130 is disposed on the anode layer 120. Onto the HIL 130, a hole transport layer (HTL) 140, an emission layer (EML) 150, an electron transport layer (ETL) 160, an electron injection layer (EIL) 180 and a cathode layer 190 are disposed. Instead of a single electron transport layer 160, optionally an electron transport layer stack (ETL) can be used.

[0342] FIG. 3 is a schematic sectional view of an OLED 100, according to another exemplary embodiment of the present invention. FIG. 3 differs from FIG. 2 in that the OLED 100 of FIG. 3 comprises an electron blocking layer (EBL) 145 and a hole blocking layer (HBL) 155.

[0343] Referring to FIG. 3, the OLED 100 includes a substrate 110, an anode layer 120, a hole injection layer (HIL) 130 which may comprise a compound of formula (I), a hole transport layer (HTL) 140, an electron blocking layer (EBL) 145, an 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.

[0344] FIG. 4 is a schematic sectional view of an OLED 200, according to another exemplary embodiment of the present invention. FIG. 4 differs from FIGS. 2 and 3 in that the OLED 200 of FIG. 4 comprises a charge generation layer (CGL) and an additional electron transport layer (ETL) 161 which replace the hole injection layer (HIL) 130 of OLED 100 in FIG. 3. Referring to FIG. 4 the OLED 200 includes a substrate 110, an anode 120, a first electron transport layer (ETL1) 161, an n-type charge generation layer (n-type CGL) 185, a p-type charge generation layer (p-type GCL) 135 which may comprise compound of Formula (I), a first hole transport layer (HTL) 140, a first electron blocking layer (EBL) 145, a first emission layer (EML) 150, a first hole blocking layer (HBL) 155, a second electron transport layer (ETL2) 160, and a cathode 190.

[0345] FIG. 5 shows the OLED 200 including a substrate 110, an anode layer 120, a hole injection layer (HIL) 130, a first hole transport layer (HTL) 140, a first electron blocking layer (EBL) 145, a first emission layer (EML) 150, a first hole blocking layer (HBL) 155, a first electron transport layer (ETL) 160, an n-type charge generation layer (n-CGL) 185, a p-type charge generation layer (p-GCL) 135 which may comprise compound of Formula (I), a second hole transport layer (HTL) 141, a second electron blocking layer (EBL) 146, a second emission layer (EML) 151, a second hole blocking layer (EBL) 156, a second electron transport layer (ETL) 161, an electron injection layer (EIL) 180 and a cathode layer 190. The HIL may comprise a compound of Formula (I).

[0346] FIG. 6 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121) and a second anode sub-layer (122), a semiconductor layer comprising compound of Formula (I) (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), an emission layer (EML) (150), a hole blocking layer (EBL) (155), an electron transport layer (ETL) (160) and a cathode layer (190).

[0347] FIG. 7 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 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), a semiconductor layer comprising compound of Formula (I) (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), an emission layer (EML) (150), a hole blocking layer (EBL) (155), an electron transport layer (ETL) (160) and a cathode layer (190). The layers are disposed exactly in the order as mentioned before.

[0348] While not shown in FIG. 1 to FIG. 7, 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.

[0349] 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

[0350] The invention is furthermore illustrated by the following examples which are illustrative only and non-binding.

[0351] Compounds of formula (I) may be prepared as described in EP2180029A1 and WO2016097017A1.

Thermogravimetric Analysis

[0352] The term TGAS% denotes the temperature at which 5% weight loss occurs during thermogravimetric analysis and is measured in ? C.

[0353] The TGAS% value may be determined by heating a 9-11 mg sample in a thermogravimetric analyzer at a heating rate of 10 K/min in an open 100 ?L aluminum pan, under a stream of nitrogen at a flow rate of 20 mL/min in the balance area and of 30 mL/min in the oven area.

[0354] The TGA5% value may provide an indirect measure of the volatility and/or decomposition temperature of a compound. In first approximation, the higher the TGA5% value the lower is the volatility of a compound and/or the higher the decomposition temperature.

Glass Transition Temperature

[0355] The glass transition temperature (Tg) is measured under nitrogen and using a heating rate of 10 K per min in a Mettler Toledo DSC.sub.822e differential scanning calorimeter as described in DIN EN ISO 11357, published in March 2010.

Calculated HOMO and LUMO

[0356] 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 6-31 G* 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

[0357] For the examples according to the invention and comparative examples in Table 3, 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 an atmosphere comprising 97.6 vol.-% nitrogen and 2.4 vol.-% oxygen.

[0358] Then, N-({[1,1-biphenyl]-4-yl)-9,9,dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine} (compound F3, cf. above) and compound of formula (I) or a comparative compound according to Table 3 were vacuum deposited on the anode, to form a HIL having a thickness of 10 nm. The amount of compound of formula (I) in the HIL can be seen in Table 3.

[0359] Then, N-({[1,1-biphenyl]-4-yl)-9,9, dimethyl-N-(4-(9-phenyl-9H-carb azol-3-yl)phenyl)-9H-fluoren-2-amine } was vacuum deposited on the HIL, to form a first HTL having a thickness of 121 nm.

[0360] Then N-([1,1-biphenyl]-4-yl)-9,9-diphenyl-N-(4-triphenyl silyl)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.

[0361] Then 97 vol.-% H09 (Sun Fine Chemicals, Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue dopant were deposited on the EBL, to form a first blue-emitting EML with a thickness of 20 nm.

[0362] Then the hole blocking layer is 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.

[0363] Then, the electron transporting layer (ETL) having a thickness of 31 nm is 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.-% LiQ.

[0364] Then Yb was evaporated at a rate of 0.01 to 1 ?/s at 10.sup.?7 mbar to form an electron injection layer with a thickness of 2 nm on the electron transporting layer.

[0365] Ag/Mg (90:10 vol %) is evaporated at a rate of 0.01 to 1 ?/s at 10.sup.?7 mbar to form a cathode with a thickness of 13 nm.

[0366] Then, N-({[1,1-biphenyl]-4-yl)-9,9, dimethyl-N-(4-(9-phenyl-9H-carb azol-3-yl)phenyl)-9H-fluoren-2-amine } was vacuum deposited on the cathode layer to form a capping layer with a thickness of 75 nm.

[0367] 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.

[0368] Organic electronic device comprising a charge generation layer (CGL)

[0369] For the top emission OLED devices, a substrate with dimensions of 150 mm?150 mm?0.7 mm was ultrasonically cleaned with 2% aqueous solution of Deconex FPD 211 for 7 minutes and then pure water for 5 minutes, and dried for 15 minutes in a spin dryer. Subsequently, Ag was deposited as anode at a pressure of 10.sup.?5 to 10.sup.?7 mbar on the substrate.

[0370] Then N-([1,1-biphenyl]-2-yl)-N-(9.9-dimethyl-9H-fluoren-2-yl)-9,9spirobi [fluoren]-2-amine was vacuum deposited with 8 vol % 4,4,4-((1E,1E,1E)-cyclopropane-1,2,3-triylidenetris(cyanomethanylylidene))tris(2,3,5,6- tetrafluoobenzonitrile) to form a hole injection layer having a thickness 10 nm.

[0371] Then N-([1,1-biphenyl]-2-yl)-N-(9.9-dimethyl-9H-fluoren-2-yl)-9,9spirobi [fluoren]-2-amine was vacuum deposited, to form a first hole transport layer having a thickness of 24 nm

[0372] Then N-([1,1-biphenyl]-4-yl)-9,9-diphenyl-N-(4-triphenyl silyl)phenyl)-9H-fluoren-2-amine was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0373] Then 97 vol.-% H09 (Sun Fine Chemicals, Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue dopant were deposited on the EBL, to form a first blue-emitting EML with a thickness of 20 nm.

[0374] Then 2-(3-(9,9-dimethyl-9H-fluoren-2-yl)-[1,1-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine was vacuum deposited to form a first hole blocking layer having a thickness of 5 nm.

[0375] Then, 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.-% LiQ were vacuum deposited on the first hole blocking layer to form a first electron transport layer having a thickness of 25 nm.

[0376] Then the first n-type CGL having a thickness of 15 nm is formed on the ETL1 by co-depositing 99 vol.-% 2,2-(1,3-Phenylene)bis[9-phenyl-1,10-phenanthroline] and 1 vol.-% Li.

[0377] Then the first p-type CGL having a thickness of 10 nm is formed on the first n-type CGL by co-depositing N-([1,1-biphenyl]-2-yl)-N-(9.9-dimethyl-9H-fluoren-2-yl)-9,9spirobi [fluoren]-2-amine with a compound according to formula (I) or a comparative example according to table 4.

[0378] Then a second hole transport layer having a thickness of 36 nm is formed on the first p-type CGL by depositing N-([1,1-biphenyl]-2-yl)-N-(9.9-dimethyl-9H-fluoren-2-yl)-9,9spirobi[fluoren]-2-amine.

[0379] Then a second electron blocking layer having a thickness of 5 nm is formed on the second hole transport layer by depositing N-([1,1-biphenyl]-4-yl)-9,9-diphenyl-N-(4-triphenylsilyl)phenyl)-9H-fluoren-2-amine,

[0380] Then 97 vol.-% H09 (Sun Fine Chemicals, Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue dopant were deposited on the second EBL, to form a second blue-emitting EML with a thickness of 20 nm.

[0381] Then a second hole blocking layer having a thickness of 5 nm is formed on the second blue-emitting EML.

[0382] Then, 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.-% LiQ were vacuum deposited on the second hole blocking layer to form a second electron transport layer having a thickness of 25nm.

[0383] Then the second n-type CGL having a thickness of 15 nm is formed on the ETL2 by co-depositing 99 vol.-% 2,2-(1,3-Phenylene)bis[9-phenyl-1,10-phenanthroline] and 1 vol.-% Li.

[0384] Then the second p-type CGL having a thickness of 10 nm is formed on the second n-type CGL by co-depositing N-([1,1-biphenyl]-2-yl)-N-(9.9-dimethyl-9H-fluoren-2-yl)-9,9spirobi[fluoren]-2-amine with a compound according to formula (I) or a comparative example according to Table 4.

[0385] Then a third hole transport layer having a thickness of 57 nm is formed on the second p-type CGL by depositing N-([1,1-biphenyl]-2-yl)-N-(9.9-dimethyl-9H-fluoren-2-yl)-9,9spirobi[fluoren]-2-amine.

[0386] Then a third electron blocking layer having a thickness of 5 nm is formed on the third hole transport layer by depositing N-([1,1-biphenyl]-4-yl)-9,9-diphenyl-N-(4-triphenylsilyl)phenyl)-9H-fluoren-2-amine,

[0387] Then 97 vol.-% H09 (Sun Fine Chemicals, Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue dopant were deposited on the third EBL, to form a third blue-emitting EML with a thickness of 20 nm.

[0388] Then a third hole blocking layer having a thickness of 5 nm is formed on the third blue-emitting EML.

[0389] Then, 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.-% LiQ were vacuum deposited on the third hole blocking layer to form a third electron transport layer having a thickness of 31 nm.

[0390] Then Yb was evaporated at a rate of 0.01 to 1 ?/s at 10.sup.?7 mbar to form an electron injection layer with a thickness of 2nm on the electron transporting layer.

[0391] Ag/Mg (90:10 vol %) is evaporated at a rate of 0.01 to 1 ?/s at 10.sup.?7 mbar to form a cathode with a thickness of 13 nm.

[0392] Then, N-({[1,1-biphenyl]-4-yl)-9,9, dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine } was vacuum deposited on the cathode layer to form a capping layer with a thickness of 75 nm.

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 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 CIE coordinates are determined by measuring the luminance in cd/m.sup.2 using an Instrument Systems CAS-140CT array spectrometer (calibrated by Deutsche Akkreditierungsstelle (DAkkS)) for each of the voltage values. The cd/A efficiency at 10 mA/cm2 is determined by interpolating the luminance-voltage and current-voltage characteristics, respectively.

[0393] In bottom emission devices, the emission is predominately Lambertian and quantified in percent external quantum efficiency (EQE). To determine the efficiency EQE in % the light output of the device is measured using a calibrated photodiode at 10 mA/cm2.

[0394] In top emission devices, the emission is forward directed, non-Lambertian and also highly dependent on the mirco-cavity. Therefore, the efficiency EQE will be higher compared to bottom emission devices. To determine the efficiency EQE in % the light output of the device is measured using a calibrated photodiode at 10 mA/cm.sup.2.

[0395] Lifetime LT of the device is measured at ambient conditions (20? C.) and 30 mA/cm.sup.2, using a Keithley 2400 sourcemeter, and recorded in hours.

[0396] The brightness of the device is measured using a calibrated photo diode. The lifetime LT is defined as the time till the brightness of the device is reduced to 97% of its initial value.

[0397] The increase in operating voltage ?U is used as a measure of the operational voltage stability of the device. This increase is determined during the LT measurement and by subtracting the operating voltage after 1 hour after the start of operation of the device from the operating voltage after 100 hours.

?U=[U100 h)?U(1h)]

or the operating voltage after 1 hour after the start of operation of the device from the operating voltage after 400 hours.

?U=[U400 h)?U(1h)]

The smaller the value of ?U the better is the operating voltage stability.

Technical Effect of the Invention

[0398] In Table 1 and 2 are shown LUMO levels for inventive compounds C1 to C.sub.25. 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 6-31 G* basis set in the gas phase.

Table 1: Calculated LUMO levels of compounds of formula (I) , whereby R, R and R are CN and Ar.sup.1, Ar.sup.2 and Ar.sup.3 as shown.

TABLE-US-00002 Compound Ar.sup.1 Ar.sup.2 Ar.sup.3 LUMO [eV] E1 [00118] [00119] [00120] ?4.58 E2 [00121] [00122] [00123] ?4.90 E3 [00124] [00125] [00126] ?5.00 C1 [00127] [00128] [00129] ?4.86 C2 [00130] [00131] [00132] ?5.21 C3 [00133] [00134] [00135] ?5.44 C4 [00136] [00137] [00138] ?5.64 C5 [00139] [00140] [00141] ?5.29 C6 [00142] [00143] [00144] ?5.55 C7 [00145] [00146] [00147] ?5.29 C8 [00148] [00149] [00150] ?5.45 C9 [00151] [00152] [00153] ?5.43 C10 [00154] [00155] [00156] ?4.89 C11 [00157] [00158] [00159] ?5.87 C12 [00160] [00161] [00162] ?5.19 C13 [00163] [00164] [00165] ?4.88 C14 [00166] [00167] [00168] ?4.48 C15 [00169] [00170] [00171] ?5.21 C16 [00172] [00173] [00174] ?5.05 C17 [00175] [00176] [00177] ?4.99 C18 [00178] [00179] [00180] ?4.92 C19 [00181] [00182] [00183] ?5.09 C20 [00184] [00185] [00186] ?4.91 C21 [00187] [00188] [00189] ?5.1 C22 [00190] [00191] [00192] ?5.01 C23 [00193] [00194] [00195] ?5.18 C24 [00196] [00197] [00198] ?5.21 C25 [00199] [00200] [00201] ?5.36 C26 [00202] [00203] [00204] ?5.10
As comparative compounds the compounds E1 to E3 as shown in table 1 were used

[0399] In Table 2 the TGA.sup.5% [? C.] and T.sub.g [? C.] for three inventive compounds and the three comparative compounds are shown.

TABLE-US-00003 TABLE 2 TGA 5% [? C.] and T.sub.g [? C.] for three inventive compounds and the three comparative compounds Material TGA 5% [? C.] T.sub.g [? C.] E1 264 65 E2 270 78 E3 295 89 C15 339 118 C16 295 91 C20 322 93 C26 352 118

[0400] As can be seen from table 2, the TGA5% value may be higher than for the comparative compounds. The glass transition temperature may be higher than for the comparative compounds.

[0401] A higher TGA5% may be an indication for a lower volatility which may be beneficial for the manufacturing of an electronic device.

[0402] A higher glass transition temperature (Tg) may be beneficial for a longer life time of an electronic device.

[0403] In Table 3 performance data for organic electroluminescent devices comprising a hole injection layer (HIL) comprising comparative and inventive compounds are shown:

TABLE-US-00004 TABLE 3 Organic electronic devices comprising an hole injection layer (HIL) comprising comparative and inventive compounds. LT97 ?V U [V] Ceff ([10 at 30 (100-1 h) C at 10 mA/cm.sup.2] mA/cm.sup.2 [30 mA/cm.sup.2, Material (vol %) CIE-y mA/cm.sup.2 [cd/A]) [h] RT] [V] E1 5 0.048 4.08 6.34 39 0.15 E2 3 0.046 3.73 6.27 29 0.06 E3 4 0.044 3.75 6.46 72 0.07 C15 3 0.048 3.74 6.52 92 0.02 C16 5 0.041 3.66 5.90 108 0.02 C26 3 0.045 3.75 6.51 124 0.146 C26 5 0.045 3.71 6.48 113 0.066 C = concentration; Ceff = current efficiency; LT = Life time; ?V = voltage rise.

[0404] As can be seen from Table 3, LT97 at 30 mA/cm.sup.2 is higher than for the comparative examples

[0405] A long lifetime may be beneficial for long-time stability of devices.

[0406] In Table 4 performance data for organic electroluminescent devices comprising a p-type charge injection layer (p-type CGL) comprising inventive compounds are shown.

TABLE-US-00005 TABLE 4 Organic electronic devices comprising a p-type charge injection layer (p-type CGL) comprising inventive compounds ?V (400-1 h) Concentration Ceff ([15 mA/ LT97 at 30 [30 mA/cm.sup.2, Material (%) cm.sup.2] [cd/A]) mA/cm.sup.2 [h] RT] [V] E3 10 23.16 74 0.85 C15 10 25.05 133 0.41 C16 10 23.82 103 0.43

[0407] As can be seen from Table 4, the current efficiency may be higher than for the comparative example. LT97 at 30 mA/cm2 may be higher than for the comparative example. The voltage rise may be lower than for the comparative example.

[0408] A long lifetime may be beneficial for long-time stability of devices.

[0409] A high efficiency may be beneficial for reduced power consumption and improved battery life, in particular in mobile devices.

[0410] A reduced increase in operating voltage over time may be an indication for improved stability of the electronic device. 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.