ORGANIC ELECTRONIC DEVICES COMPRISING A LAYER OF A PYRIDINE COMPOUND AND A 8-HYDROXYPQUINOLINOLATO EARTH ALKALINE METAL, OR ALKALI METAL COMPLEX

Abstract

The present invention provides an organic electronic device including a first electrode, a second electrode, and an organic layer interposed between the first electrode and the second electrode, wherein the organic layer comprises an organic metal complex of formula

##STR00001##

and a compound of formula

##STR00002##

Organic light emitting devices (OLEDs) having superior life time, power efficiency, quantum efficiency and/or a low operating voltage are obtained, when the organic layer comprising the compounds of formula I and II constitutes the electron transport layer of an OLED.

Claims

1. An organic electronic device including a first electrode, a second electrode, and an organic layer interposed between the first electrode and the second electrode, wherein the organic layer comprises an organic metal complex of formula ##STR00069## and a compound of formula ##STR00070## wherein R.sub.1 and R.sup.2 are independently of each other F, C.sub.1-C.sub.8alkyl, or C.sub.6-C.sub.18aryl, which may optionally be substituted by one, or more C.sub.1-C.sub.8alkyl groups, or two substituents R.sup.1 and/or R.sup.2 combine to form a fused benzene ring group, which may optionally be substituted by one, or more C.sub.1-C.sub.8alkyl groups, a and b are independently of each other 0, or an integer 1 to 3, R.sup.81, R.sup.82, R.sup.83, R.sup.84, R.sup.81′, R.sup.82′, R.sup.83′, and R.sup.84′ are independently of each other H, C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18alkyl which is substituted by E and/or interrupted by D, C.sub.6-C.sub.24aryl, C.sub.6-C.sub.24aryl which is substituted by G, C.sub.2-C.sub.20heteroaryl, or C.sub.2-C.sub.20heteroaryl which is substituted by G, Q is an arylene or heteroarylene group, each of which may optionally be substituted by G; D is —CO—; —COO—; —S—; —SO—; —SO.sub.2—; —O—; —NR.sup.25—; —SiR.sup.30R.sup.31—; —POR.sup.32—; —CR.sup.23═CR.sup.24—; or —C≡C—; and E is —OR.sup.29; —SR.sup.29; —NR.sup.25R.sup.26; —COR.sup.28; —COOR.sup.27; —CONR.sup.25R.sup.26; —CN; or F; G is E, C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18alkyl which is interrupted by D, C.sub.1-C.sub.18perfluoroalkyl, C.sub.1-C.sub.18alkoxy, or C.sub.1-C.sub.18alkoxy which is substituted by E and/or interrupted by D, wherein R.sup.23 and R.sup.24 are independently of each other H, C.sub.6-C.sub.18aryl; C.sub.6-C.sub.18aryl which is substituted by C.sub.1-C.sub.18alkyl, or C.sub.1-C.sub.18alkoxy; C.sub.1-C.sub.18alkyl; or C.sub.1-C.sub.18alkyl which is interrupted by —O—; R.sup.25 and R.sup.26 are independently of each other C.sub.6-C.sub.18aryl; C.sub.6-C.sub.18aryl which is substituted by C.sub.1-C.sub.18alkyl, or C.sub.1-C.sub.18alkoxy; C.sub.1-C.sub.18alkyl; or C.sub.1-C.sub.18alkyl which is interrupted by —O—; or R.sup.25 and R.sup.26 together form a five or six membered ring, R.sup.27 and R.sup.28 are independently of each other C.sub.6-C.sub.18aryl; C.sub.6-C.sub.18aryl which is substituted by C.sub.1-C.sub.18alkyl, or C.sub.1-C.sub.18alkoxy; C.sub.1-C.sub.18alkyl; or C.sub.1-C.sub.18alkyl which is interrupted by —O—, R.sup.29 is C.sub.6-C.sub.18aryl; C.sub.6-C.sub.18aryl, which is substituted by C.sub.1-C.sub.18alkyl, or C.sub.1-C.sub.18alkoxy; C.sub.1-C.sub.18alkyl; or C.sub.1-C.sub.18alkyl which is interrupted by —O—, R.sup.30 and R.sup.31 are independently of each other C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.18aryl, or C.sub.6-C.sub.18aryl, which is substituted by C.sub.1-C.sub.18alkyl, R.sup.32 is C.sub.1-C.sub.18alkyl, C.sub.6-C.sub.18aryl, or C.sub.6-C.sub.18aryl, which is substituted by C.sub.1-C.sub.18alkyl M is an alkali metal atom, or an earth alkaline metal atom, n is 1, if M is an alkali metal atom, n is 2, if M is an earth alkali metal atom.

2. The organic electronic device according to claim 1, wherein Q is a group of formula ##STR00071## wherein R.sup.85 is H, C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18alkyl which is substituted by E and/or interrupted by D, C.sub.6-C.sub.24aryl, C.sub.6-C.sub.24aryl which is substituted by G, C.sub.2-C.sub.20heteroaryl, or C.sub.2-C.sub.20heteroaryl which is substituted by G, and D, E and G are as defined in claim 1.

3. The organic electronic device according to claim 2, wherein the compound of formula II is a compound of formula ##STR00072## wherein Q is ##STR00073## R.sup.85 is H, or C.sub.1-C.sub.18alkyl and R.sup.85′ is H, C.sub.1-C.sub.18alkyl, or ##STR00074##

4. The organic electronic device according to claim 3, wherein the compound of formula IIb is a compound of formula ##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079## ##STR00080##

5. The organic electronic device according to claim 1, wherein M is Li, Na, or K and n is 1.

6. The organic electronic device according to claim 5, wherein the compound of formula I is a compound of formula ##STR00081##

7. The organic electronic device according to claim 1, which is an organic light emitting device, comprising an anode, a hole injection layer, a hole transport layer, a light emitting layer, a hole and exciton blocking layer, an electron transport layer, an electron injection layer and a cathode, wherein the organic layer comprising the compounds of formula I and II constitutes the electron transport layer.

8. The organic electronic device according to claim 7, wherein the electron transport layer comprises a mixture of a compound of formula ##STR00082## and a compound of formula (A-1).

9. The organic electronic device according to claim 7, wherein the electron injection layer comprises, or consists of potassium fluoride.

10. The organic electronic device according to any of claim 7, wherein the light emitting layer comprises a compound of the formula ##STR00083## wherein the symbols have the following meanings: M.sup.1 is a metal atom selected from the group consisting of Co, Rh, Ir, Nb, Pd, Pt, Fe, Ru, Os, Cr, Mo, W, Mn, Tc, Re, Cu, Ag and Au in any oxidation state possible for the respective metal atom; carbene is a carbene ligand which may be uncharged or monoanionic and monodentate, bidentate or tridentate, with the carbene ligand also being able to be a biscarbene or triscarbene ligand; L is a monoanionic or dianionic ligand, which may be monodentate or bidentate; K is an uncharged monodentate or bidentate ligand selected from the group consisting of phosphines; phosphonates and derivatives thereof, arsenates and derivatives thereof; phosphites; CO; pyridines; nitriles and conjugated dienes which form a π complex with M.sup.1; n1 is the number of carbene ligands, where n1 is at least 1 and when n1>1 the carbene ligands in the complex of the formula I can be identical or different; m is the number of ligands L, where m can be 0 or ≧1 and when m>1 the ligands L can be identical or different; o is the number of ligands K, where o can be 0 or ≧1 and when o>1 the ligands K can be identical or different; where the sum n1+m+o is dependent on the oxidation state and coordination number of the metal atom and on the denticity of the ligands carbene, L and K and also on the charge on the ligands, carbene and L, with the proviso that n1 is at least 1.

11. The organic electronic device according to claim 10, wherein the compound of the formula IX is a compound of the formula ##STR00084##

12. The organic electronic device according to claim 1, wherein the hole transport layer comprises a compound of formula ##STR00085## doped with molybdenum oxide (MoO.sub.x), especially MoO.sub.3, or rhenium oxide (ReO.sub.x), especially ReO.sub.3.

13. An organic electron transport layer, comprising an organic metal complex of formula I as defined in claim 1 and a compound of formula II as defined in claim 1.

14. A method of using the organic layer according to claim 13 in an organic electronic device.

15. An apparatus comprising an organic electronic device according to claim 1.

16. An apparatus comprising an organic electron transport layer according to claim 13.

Description

EXAMPLES

Comparative Application Example 1

[0097] The ITO substrate used as the anode is first cleaned with commercial detergents for LCD production (Deconex® 20NS, and 25ORGAN-ACID® neutralizing agent) and then in an acetone/isopropanol mixture in an ultrasound bath. To eliminate any possible organic residues, the substrate is exposed to a continuous ozone flow in an ozone oven for a further 25 minutes. This treatment also improves the hole injection properties of the ITO. Then AJ20-1000 (commercially available from Plexcore) is spin-coated and dried to form a hole injection layer (˜40 nm).

[0098] Thereafter, the organic materials specified below are applied by vapor deposition to the clean substrate at a rate of approx. 0.5-5 nm/min at about 10.sup.−8 mbar. As a hole transport and exciton blocker, Ir(dpbic).sub.3 (V1) is applied to the substrate with a thickness of 45 nm, wherein the first 35 nm are doped with MoO.sub.x (˜50%) to improve the conductivity.

##STR00062##

(for preparation, see Ir complex (7) in the application WO 2005/019373).

[0099] Subsequently, a mixture of 30% by weight of compound

##STR00063##

35% by weight of compound (V1) and 35% by weight of compound

##STR00064##

described in PCT/EP2009/067120) is applied by vapor deposition in a thickness of 20 nm.

[0100] Subsequently, the material

##STR00065##

is applied by vapor deposition with a thickness of 5 nm as exciton and hole blocker.

[0101] Next, a mixture of 50% by weight of

##STR00066##

and 50% by weight of

##STR00067##

(8-hydroxyquinolinolato-lithium (Liq)) is applied as electron transport layer by vapor deposition in a thickness of 40 nm, as are a 2 nm-thick potassium fluoride layer (electron injection layer) and finally a 100 nm-thick Al electrode.

Comparative Application Example 2

[0102] Production and construction of an OLED as in the comparative application example 1, except compound

##STR00068##

is used alone instead of the mixture of BCP and Liq.

Comparative Application Example 3

[0103] Production and construction of an OLED as in the comparative application example 1, except Liq is used alone instead of the mixture of BCP and Liq.

Application Example 1

[0104] Production and construction of an OLED as in the comparative application example 1, except a mixture of 75% by weight of compound A-1 and 25% by weight of Liq is used instead of the mixture of BCP and Liq.

Application Example 2

[0105] Production and construction of an OLED as in the comparative application example 1, except a mixture of 50% by weight of compound A-1 and 50% by weight of Liq is used instead of the mixture of BCP and Liq.

Application Example 3

[0106] Production and construction of an OLED as in the comparative application example 1, except a mixture of 25% by weight of compound A-1 and 75% by weight of Liq is used instead of the mixture of BCP and Liq.

[0107] To characterize the OLED, electroluminescence spectra are recorded at various currents and voltages. In addition, the current-voltage characteristic is measured in combination with the light output emitted. The light output can be converted to photometric parameters by calibration with a photometer. To determine the lifetime, the OLED is operated at a constant current density and the decrease in the light output is recorded. The lifetime is defined as that time which lapses until the luminance decreases to half of the initial luminance.

[0108] V at 300 cd/m.sup.2, Im/W at 300 cd/m.sup.2, EQE (%) at 300 cd/m.sup.2 and lifetime (h) at 300 cd/m.sup.2 measured for the devices of the Application Examples and Comparative Application Examples are shown in the Tables 1-1 and 1-2 below, wherein the measured data of the Comparative Application Example 1 (Table 1-1) and 3 (Table 1-2), respectively are set to 100 and the data of the Application Examples are specified in relation to those of Comparative Application Example 1 and 3, respectively.

TABLE-US-00001 TABLE 1-1 EQE.sup.4) (%) ET Im/W at at Lifetime (h) Device Layer V at 300 cd/m.sup.2 300 cd/m.sup.2 300 cd/m.sup.2 at 300 cd/m.sup.2 Color Appl. Liq.sup.1) 86 177 144 567 X = 0.174 Ex. 2 Cpd. A-1.sup.1) Y = 0.310 Comp. Liq.sup.1) 100 100 100 100 X = 0.167 Appl. BCP.sup.1) Y = 0.282 Ex. 1

TABLE-US-00002 TABLE 1-2 EQE.sup.4) (%) ET Im/W at at Lifetime (h) Device Layer V at 300 cd/m.sup.2 300 cd/m.sup.2 300 cd/m.sup.2 at 300 cd/m.sup.2 Color Appl. Liq.sup.2) 43 297 124 206 X = 0.174 Ex. 1 Cpd. A-1.sup.3) Y = 0.312 Appl. Liq.sup.1) 44 271 116 272 X = 0.174 Ex. 2 Cpd. A-1.sup.1) Y = 0.310 Appl. Liq.sup.3) 51 230 114 392 X = 0.173 Ex. 3 Cpd. A-1.sup.2) Y = 0.309 Comp. Cpd. A-1 44 264 112 132 X = 0.175 Appl. Y = 0.314 Ex. 2 Comp. Liq 100 100 100 100 X = 0.171 Appl. Y = 0.300 Ex. 3 .sup.1)50% by weight. .sup.2)25% by weight .sup.3)75% by weight .sup.4)External quantum efficiency (EQE) is # a of generated photons escaped from a substance or a device/# of electrons flowing through it. ET Layer = Electron Transport Layer. EI Layer = Electron Injection Layer.

[0109] The life time, power efficiency, quantum efficiency and/or voltage at 300 cd/m.sup.2 of the devices of the Application Examples are superior as compared with the devices of the Comparative Application Examples.