Organic electroluminescence device emitting white light

• US 6,803,120 B2
• Filed: 12/28/2000
• Issued: 10/12/2004
• Est. Priority Date: 12/28/1999
• Status: Expired due to Term

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: Fukuoka, Kenichi, Hosokawa, Chishio, Tagami, Sanae
• Primary Examiner(s): GARRETT, DAWN L
• Application Number:
  US09/749,749
• Publication Number:
  US 20020168544A1
• Time in Patent Office: 1,384 Days
• Field of Search: 428/690, 428/917, 313/502, 313/503, 313/504, 313/506, 313/509, 257/101
• US Class Current: 428/690
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1003 Carbocyclic compounds
• CPC Class Codes: C09K 2211/1007 Non-condensed systems
• CPC Class Codes: C09K 2211/1011 Condensed systems
• CPC Class Codes: C09K 2211/1014 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• 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 85/622 containing four rings, e.g. pyrene
• CPC Class Codes: H10K 85/623 containing five rings, e.g. pentacene
• CPC Class Codes: H10K 85/624 containing six or more rings
• CPC Class Codes: H10K 85/626 containing more than one polycyclic condensed aromatic rings, e.g. bis-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 85/633 comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

An organic electroluminescence device emitting white light which emits white light and exhibits properties sufficient for practical applications, i.e., a high efficiency of light emission and a long life, is provided. The organic electroluminescence device emitting white light comprises a pair of electrodes and a layer of a light emitting medium disposed between the pair of electrodes, wherein the layer of a light emitting medium comprises a light emitting material emitting blue light and a fluorescent compound having at least one structure selected from a fluoranthene skeleton structure, a pentacene skeleton structure and a perylene skeleton structure.

Claims

1. An organic electroluminescence device emitting white light which comprises a pair of electrodes and a layer of a light emitting medium disposed between the pair of electrodes, wherein the layer of a light emitting medium comprises a light emitting material emitting blue light and a fluorescent compound having at least one structure selected from a fluoranthene skeleton structure and a pentacene skeleton structure.

2. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of a light emitting medium contacts an anode and comprises an oxidizing agent.

3. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of a light emitting medium contacts a cathode and comprises a reducing agent.

4. An organic electroluminescence device emitting white light according to claim 1, wherein the fluorescent compound is selected from the group consisting of the following compounds (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (14), (15), (16), (17), (18), (19), (20), (1′

) and (2′

);

wherein in the above formulae (1) to (11) and (14) to (16) X¹ to X²⁰ each independently represent hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbpn atoms, a linear, branched or cyclic alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 30 carbons atoms, a substituted or unsubstituted arylalkylamino group having 7 to 30 carbon atoms or a substituted or unsubstituted alkenyl group having 8 to 30 carbon atoms, adjacent substituents and adjacent groups represented by X¹ to X₂₀ may be bonded to each other to form a cyclic structure, and, when the adjacent substituents represented by X¹ to X²⁰ are aromatic groups, the substituents may the same group;

wherein in the above formulae (17) and (18), R¹ to R⁴ each independently represent an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, any of a pair of groups represented by R¹ to R² and a pair of groups represented by R³ and R⁴ may be bonded to each other through a carbon-carbon bond, —

O—

or —

S—

,R⁵ to R¹⁶ each independently represent hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a linear, branched or cyclic alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, a substituted or unsubstituted arylalkylamino group having 7 to 30 carbon atoms or a substituted alkenyl group having 8 to 30 carbon atoms, and adjacent substituents and adjacent groups represented by R⁵ to R¹⁶ may be bonded to each other to form a cyclic structure;

wherein in the above formula (19),R¹ to R¹⁴ each independently represent hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an arylalkyl group having 6 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylamino group having 6 to 30 carbon atoms, an alkylamino group having 2 to 20 carbon atoms or an arylalkylamino group having 6 to 30 carbon atoms, the groups represented by R¹ to R¹⁴ may be substituted, and at least one pair of groups represented by R¹ to R¹⁴ which are adjacent to each other are not hydrogen atom and form a cyclic structure;

wherein in the above formula (20),R¹⁵ to R²⁶ each independently represent hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an arylalkyl group having 6 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylamino group having 6 to 30 carbon atoms, an alkylamino group having 2 to 20 carbon atoms or an arylalkylamino group having 6 to 30 carbon atoms, the groups represented by R¹⁵ to R²⁶ may be substituted, at least one pair of groups represented by R¹⁵ to R²⁶ which are adjacent to each other are not hydrogen atom and form a cyclic structure, and Ar¹ and Ar² each represent a substituted or unsubstituted aryl group having 6 to 30 carbon atoms or a substituted or unsubstituted heterocyclic group having 5 to 30 carbon atoms;

5. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of a light emitting medium comprises a hole transporting material or hole injecting material.

6. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of light emitting medium comprises a hole transporting layer or a hole injecting layer.

7. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of light emitting medium comprises an electron transporting material or an electron injecting material.

8. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of light emitting medium comprises an electron transporting layer or an electron injecting material.

9. An organic electroluminescence device emitting white light according to claim 1, wherein a layer of an inorganic compound is disposed between at least one of electrodes and the layer of light emitting medium.

10. An organic electroluminescence device emitting white light according to claim 1, wherein the fluroscent compound has an electrode-donating group.

11. An organic electroluminescence device emitting white light according to claim 1, wherein the fluorescent compound has a peak wavelenght of fluorescence at 540 to 650nm.

12. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of a light emitting medium comprises light emitting layer A comprising the light emitting material emitting blue light and fluorescent compound.

13. An organic electroluminescence device emitting white light according to claim 12, wherein light emitting layer A further comprises a fluorescent dopant emitting blue light.

14. An organic electroluminescence device emitting white light according to claim 13, wherein the fluorescent dopant emitting blue light is at least one compound selected from styrylamines, styryl compounds substitued with an amine and compounds having a condensed aromatic ring.

15. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of a light emitting medium comprises light emitting layer emitting blue light and light emitting layer A which comprises the light emitting material emitting blue light and the fluorescent compound.

16. An organic electroluminescence device emitting white light according to claim 15, wherein light emitting layer A further comprises a fluorescent dopant emitting blue light.

17. An organic electroluminescence device emitting white light according to claim 16, wherein the fluorescent dopant emitting blue light is at least one compound selected from styrylamined, styryl compounds substitued with an amine and compounds having a condensed aromatic ring.

18. An organic electroluminescence device emitting white light according to claim 15, wherein the light emitting layer emitting blue light further comprises a fluorescent dopant emitting blue light.

19. An organic electroluminescence device emitting white light according to claim 18, wherein the fluorescent dopant emitting blue light is at least one compound selected from styrylamines, styrl compounds substituted with an amine and compounds having a condensed aromatic ring.

20. An organic electroluminescence device emitting white light according to claim 1, wherein the layer of a light emitting meduim comprises a light emitting layer B comprising the light emitting material emitting blue light and a layer comprising the fluorescent compound.

21. An organic electroluminescence device emitting white light according to claim 20, wherein light emitting layer B furhter comprises a fluorescent dopant emitting blue light.

22. An organic electroluminescence device emitting white light according to claim 21, wherein the fluorescent dopant emitting blue light is at least one compound selected from styrylamines, styryl compounds substituted with an amine and compounds having a condensed aromatic ring. nitrogen atoms which are substituted with an aromatic group and having at least one alkenyl group.

23. An organic electroluminescence device emitting white light according to claim 1, wherein the light emitting material emmitting blue light is a styryl derivation, an antracene derivative or an aromatic amine.

24. An organic electroluminescence device emitting white light according to claim 23, wherein the styrly derivative is at least one compound selected from distyryl derivatives, tristyryl derivatives, tetraastyryl derivatives and styrylamine derivatives.

25. An organic electroluminescence device emitting white light according to claim 23, wherein the anthrance derivative is a compound having a phenylanthracene skeleton structure.

26. An organic electroluminescence device emitting white light according to claim 23, wherein the aromatic amine is a compound having 2 to 4 nitrogen atoms which are substituted with an aromatic group.

27. An organic electroluminescence device emitting white light according to claim 23, wherein the aromatic amine is a compound having 2 to 4 nitrogen atoms which are substituted with an aromatic group and having at least one alkenyl group.