High performance white light-emitting OLED device

1. A white light-emitting OLED device having an anode and a cathode, comprising:

a) a first light-emitting layer provided over the anode and containing a first host material and a first light-emitting material, wherein the first host material is a mixture of one or more mono-anthracene derivatives and one or more aromatic amine derivatives, wherein the mono-anthracene derivative(s) being provided in a volume fraction range of 5% to 50% relative to the total host volume, and the aromatic amine derivative(s) being provided in a volume fraction range of 50% to 95% relative to the total host volume, and wherein the first light-emitting material has a peak emission in the yellow to red portion of the spectrum; and

b) a second light-emitting layer provided over or under the first light-emitting layer, wherein the second light-emitting layer has a peak emission in the blue to cyan portion of the spectrum, whereby white light is produced by the OLED device.

2. The white light-emitting OLED of claim 1 wherein the second light-emitting layer contains a second host material and a second light-emitting material, wherein the second host material includes one or more mono-anthracene derivatives.

3. The white light-emitting OLED of claim 2 wherein the same mono-anthracene derivative(s) are used in the first and second host materials.

4. The white light-emitting OLED of claim 2 wherein at least one of the mono-anthracene derivatives of the first or second host materials includes:

wherein:

R 1 -R 8 are H;

R 9 is not the same as R 10 ;

R 9 is a naphthyl group having no fused rings with aliphatic carbon ring members; and

R 10 is a biphenyl group having no fused rings with aliphatic carbon ring members; and

provided that R 9 and R 10 are free of amino and sulfur substituents.

5. The white light-emitting OLED of claim 2 wherein at least one of the mono-anthracene derivatives of the first or second host materials includes:

wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 represent one or more substituents on each ring and each substituent is individually selected from the following groups:

Group 1: hydrogen, or alkyl of from 1 to 24 carbon atoms;

Group 2: aryl or substituted aryl of from 5 to 20 carbon atoms;

Group 3: carbon atoms from 4 to 24 necessary to complete a fused aromatic ring of anthracenyl, pyrenyl, or perylenyl;

Group 4: heteroaryl or substituted heteroaryl of from 5 to 24 carbon atoms as necessary to complete a fused heteroaromatic ring of furyl, thienyl, pyridyl, quinolinyl or other heterocyclic systems;

Group 5: alkoxylamino, alkylamino, or arylamino of from 1 to 24 carbon atoms; and

Group 6: fluorine, chlorine, bromine or cyano.

6. The white light-emitting OLED of claim 2 wherein the second host material further includes one or more aromatic amine derivatives wherein the mono-anthracene derivative(s) being provided in a volume fraction of greater than 85% and less than 100% relative to the total host volume, and the aromatic amine derivative(s) being provided in a volume fraction of greater than 0% and less than 15%.

7. The white light-emitting OLED of claim 6 wherein the same aromatic amine derivative(s) are used in the first and the second host materials.

8. The white light-emitting OLED of claim 1 wherein the first light-emitting material is [a} selected from:

wherein for structure ia), A 1 -A 6 represent one or more substituents on each ring and where each substituent is individually selected from one of the following:

Category 1: hydrogen, or alkyl of from 1 to 24 carbon atoms;

Category 2: aryl or substituted aryl of from 5 to 20 carbon atoms;

Category 3: hydrocarbon containing 4 to 24 carbon atoms, completing a fused aromatic ring or ring system;

Category 4: heteroaryl or substituted heteroaryl of from 5 to 24 carbon atoms including thiazolyl, furyl, thienyl, pyridyl, quinolinyl or other heterocyclic systems, which are bonded via a single bond, or complete a fused heteroaromatic ring system;

Category 5: alkoxylamino, alkylamino, or arylamino of from 1 to 24 carbon atoms; or

Category 6: fluoro, chloro, bromo or cyano.

9. The white light-emitting OLED of claim 2 wherein the second light-emitting material is selected from a derivative of perylene.

10. The white light-emitting OLED of claim 2 further including an organic layer disposed over the first and second light-emitting layers, wherein the organic layer includes an electron-transporting material and a mono-anthracene derivative, and wherein the mono-anthracene derivative is present in an amount up to 50% by volume of the organic layer.

11. The white light-emitting OLED of claim 10 wherein the organic layer includes a light-emitting material, thereby providing a third light-emitting layer.

12. The white light-emitting OLED of claim 11 wherein the third light-emitting layer has a peak emission in the yellow to green portion of the spectrum.