White organic electroluminescent device

• US 20050100760A1
• Filed: 10/22/2004
• Published: 05/12/2005
• Est. Priority Date: 10/24/2003
• Status: Abandoned Application

• Current Assignee: Pentax Corporation (Hoya Corporation), ITC Inc (Mudrick Capital Management LP)
• Original Assignee: Pentax Corporation (Hoya Corporation), ITC Inc (Mudrick Capital Management LP)
• Inventors: Yokoyama, Meiso
• Application Number:
  US10/970,002
• Publication Number:
  US 20050100760A1
• Time in Patent Office: Days
• US Class Current: 428/690
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/17 Carrier injection layers
• CPC Class Codes: H10K 85/311 Phthalocyanine
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/60 Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence
• CPC Class Codes: H10K 85/615 Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: H10K 85/649 Aromatic compounds comprising a hetero atom

Abstract

A white organic EL device has an organic layer between an anode and a cathode on a substrate. The organic layer has at least a blue emitting layer, a red emitting layer, and a green emitting layer. The red emitting layer contains a blue emitting compound doped with at least one of a yellow dopant dye 14b and a red dopant dye 14c. When a voltage is applied between the anode and the cathode, each emitting layer emits blue, red, and green light respectively, therefore the white organic EL device 20 emits white light.

Claims

1. An organic electroluminescent device, emitting white light, comprising:

an organic layer between an anode and a cathode on a substrate,

said organic layer having at least;

a first blue emitting layer emitting blue light,

a first green emitting layer emitting green light, and

a red emitting layer emitting red light, containing a blue emitting compound doped with at least one of a yellow dopant dye and a red dopant dye.

2. A device according to claim 1, wherein said blue emitting compound is a hole-transporting compound.

3. A device according to claim 2, wherein said hole-transporting compound satisfies the structural formula

4. A device according to claim 3, wherein said hole-transporting compound is NPB.

5. A device according to claim 1, wherein said organic layer has in sequence from said anode, said red emitting layer, said first blue emitting layer, and said first green emitting layer.

6. A device according to claim 1, wherein said red emitting layer contains said red dopant dye, and said red dopant dye satisfies the structural formula [2];

7. A device according to claim 1, wherein said red emitting layer contains both said yellow dopant dye and said red dopant dye.

8. A device according to claim 7, wherein the content of said yellow dopant dye is higher than the content of said red dopant dye.

9. A device according to claim 8, wherein the weight ratio between said yellow dopant dye and said red dopant dye is in the range from 1.8:

1 to 2.2;

1.

10. A device according to claim 7, wherein the total weight of yellow dopant dye and said red dopant dye is not more than 2 weight percent with respect to the weight of said blue emitting compound.

11. A device according to claim 1, wherein said first blue emitting layer contains a blue dopant dye.

12. A device according to claim 1, wherein said blue emitting compound satisfies the structural formula [3];

13. A device according to claim 1, wherein said organic layer has in sequence from said anode side said first blue emitting layer, said red emitting layer, and said first green emitting layer.

14. A device according to claim 13, wherein said organic layer has a second blue emitting layer between said red emitting layer and said first green emitting layer.

15. A device according to claim 14, wherein said organic layer has a second green emitting layer on said anode side of said second blue emitting layer.

16. A device according to claim 1, wherein said organic layer has a hole-injection layer on the closest side to said anode, said hole-injection layer containing CuPc and MTDATA.

17. An organic electroluminescent device, for emitting light, comprising:

an organic layer emitting said light between an anode and a cathode on a substrate, said organic layer having a hole-injection layer on the closest side to said anode, said hole-injection layer containing CuPc and MTDATA.

18. A device according to claim 17, wherein said hole-injection layer has a first hole-injection layer containing CuPc and a second hole-injection layer containing MTDATA.

19. A device according to claim 17, wherein said hole-injection layer contains a mixture of CuPc and MTDATA.