MATERIAL FOR ORGANIC ELECTROLUMINESCENCE DEVICE AND ORGANIC ELECTROLUMINESCENCE DEVICE UTILIZING THE SAME

• US 20090017330A1
• Filed: 11/21/2007
• Published: 01/15/2009
• Est. Priority Date: 07/10/2007
• Status: Active Grant

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: Iwakuma, Toshihiro, Fukuoka, Kenichi, Endo, Jun, Numata, Masaki
• Granted Patent: US 8,114,530 B2
• Time in Patent Office: Days
• US Class Current: 428/690
• CPC Class Codes: C07D 405/14 containing three or more hetero rings
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/1044 containing two nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1059 containing three nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1074 containing more than three nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1088 containing oxygen as the only heteroatom
• CPC Class Codes: C09K 2211/185 of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd
• CPC Class Codes: C09K 2211/186 of the light metals other than alkali metals and alkaline earth metals, i.e. Be, Al or Mg
• 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 2101/10 Triplet emission
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/17 Carrier injection layers
• CPC Class Codes: H10K 50/171 Electron injection layers
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• 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: H10K 85/636 comprising heteroaromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: H10K 85/654 comprising only nitrogen as heteroatom H10K85/652 takes precedence
• CPC Class Codes: H10K 85/6572 comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole
• CPC Class Codes: H10K 85/6574 : comprising only oxygen in the heteroaromatic polycondensed ring system, e.g. cumarine dyes
• CPC Class Codes: H10K 85/6576 : comprising only sulfur in the heteroaromatic polycondensed ring system, e.g. benzothiophene
• CPC Class Codes: Y10S 428/917 : Electroluminescent

Abstract

A material for organic electroluminescence devices of the invention which is for use in combination with at least one phosphorescent metal complex has a specific heterocyclic structure. The material for organic electroluminescence devices is used as a host material or a hole transporting material. An organic electroluminescence device having an anode, a cathode and an organic thin film layer having one or more layers which is interposed between the anode and cathode, in which at least one layer of the organic thin film layer contains the material for organic electroluminescence devices, has a high emitting efficiency, causes little pixel defects, is excellent in heat resistance, and shows a long lifetime.

Claims

1. A material for organic electroluminescence devices for use in combination with at least one phosphorescent metal complex, comprising a compound represented by the following formula 1:

wherein R₁ to R₃ are each independently hydrogen atom, halogen atom, alkyl group having 1 to 40 carbon atoms which is optionally substituted, cycloalkyl group having 3 to 15 carbon atoms which is optionally substituted, heterocyclic group having 3 to 20 carbon atoms which is optionally substituted, alkoxy group having 1 to 40 carbon atoms which is optionally substituted, non condensed aryl group having 6 to 40 carbon atoms which is optionally substituted, condensed aryl group having 10 to 18 carbon atoms which is optionally substituted, aryloxy group having 6 to 20 carbon atoms which is optionally substituted, aralkyl group having 7 to 20 carbon atoms which is optionally substituted, arylamino group having 6 to 40 carbon atoms which is optionally substituted, alkylamino group having 1 to 40 carbon atoms which is optionally substituted, aralkylamino group having 7 to 60 carbon atoms which is optionally substituted, arylcarbonyl group having 7 to 40 carbon atoms which is optionally substituted, arylthio group having 6 to 20 carbon atoms which is optionally substituted, alkyl halide group having 1 to 40 carbon atoms which is optionally substituted, or cyano group, with the proviso that at least one of R₁ to R₃ is 9-carbazolyl group which is optionally substituted or azacarbazolyl group having 2 to 5 nitrogen atoms which is optionally substituted;

R₆ and R₁₀ are each independently hydrogen atom or alkyl group having 1 to 40 carbon atoms which is optionally substituted;

R₇ to R₉ are each independently hydrogen atom, halogen atom, alkyl group having 1 to 40 carbon atoms which is optionally substituted, cycloalkyl group having 3 to 15 carbon atoms which is optionally substituted, heterocyclic group having 3 to 20 carbon atoms which is optionally substituted, alkoxy group having 1 to 40 carbon atoms which is optionally substituted, non condensed aryl group having 6 to 40 carbon atoms which is optionally substituted, condensed aryl group having 10 to 18 carbon atoms which is optionally substituted, aryloxy group having 6 to 20 carbon atoms which is optionally substituted, aralkyl group having 7 to 20 carbon atoms which is optionally substituted, arylamino group having 6 to 40 carbon atoms which is optionally substituted, alkylamino group having 1 to 40 carbon atoms which is optionally substituted, aralkylamino group having 7 to 60 carbon atoms which is optionally substituted, arylcarbonyl group having 7 to 40 carbon atoms which is optionally substituted, arylthio group having 6 to 20 carbon atoms which is optionally substituted, alkyl halide group having 1 to 40 carbon atoms which is optionally substituted, or cyano group, with the proviso that when R₈ and R₉, or R₈ and R₇ are not bonded to each other thereby do not form a ring structure, at least one of R₇ to R₉ is 9-carbazolyl group which is optionally substituted, azacarbazolyl group having 2 to 5 nitrogen atoms which is optionally substituted, phenyl group which is optionally substituted, dibenzofuranyl group which is optionally substituted, or dibenzothiophenyl group which is optionally substituted;

R₈ and R₉, or R₈ and R₇ are optionally bonded to each other to form a ring structure which is optionally substituted, and R₇ or R₉ which does not form the ring structure is hydrogen atom, halogen atom, alkyl group having 1 to 40 carbon atoms which is optionally substituted, cycloalkyl group having 3 to 15 carbon atoms which is optionally substituted, heterocyclic group having 3 to 20 carbon atoms which is optionally substituted, alkoxy group having 1 to 40 carbon atoms which is optionally substituted, non-condensed aryl group having 6 to 40 carbon atoms which is optionally substituted, condensed aryl group having 10 to 18 carbon atoms which is optionally substituted, aryloxy group having 6 to 20 carbon atoms which is optionally substituted, aralkyl group having 7 to 20 carbon atoms which is optionally substituted, arylamino group having 6 to 40 carbon atoms which is optionally substituted, alkylamino group having 1 to 40 carbon atoms which is optionally substituted, aralkylamino group having 7 to 60 carbon atoms which is optionally substituted, arylcarbonyl group having 7 to 40 carbon atoms which is optionally substituted, arylthio group having 6 to 20 carbon atoms which is optionally substituted, alkyl halide group having 1 to 40 carbon atoms which is optionally substituted, or cyano group, with the proviso that R₈ and R₉, or R₈ and R₇ together with a benzene ring to which R₇ to R₉ are bonded do not form carbazolyl group;

each of R₁ to R₃ and R₆ to R₁₀ does not have a polymerizable functional group at its terminal end; and

X is sulfur atom or oxygen atom.

2. The material for organic electroluminescence devices according to claim 1, which is represented by the following formula 2:

wherein R₁ to R₃, R₆ to R₈, R₁₀ and X are the same as defined above, and definitions of R₂₀ to R₂₄ are the same as the definitions of R₁ to R₃ except for the proviso.

3. The material for organic electroluminescence devices according to claim 1, which is represented by the following formula 3:

wherein R₁ to R₃, R₆, R₇, R₉, R₁₀ and X are the same as defined above, and definitions of R₂₀ to R₂₄ are the same as the definitions of R₁ to R₃ except for the proviso.

4. The material for organic electroluminescence devices according to claim 1, which is represented by the following formula 4:

wherein R₁ to R₃, R₆, R₇ and X are the same as defined above, and definitions of R₁₈, R₁₉ and R₂₁ to R₂₃ are the same as the definitions of R₁ to R₃ except for the proviso.

5. The material for organic electroluminescence devices according to claim 1, which is represented by the following formula 5:

wherein R₁ to R₃, R₆, R₇, R₈, R₁₀ and X are the same as defined above, and definitions of R₂₀, R₂₂ to R₂₄ and R₂₅ to R₂₉ are the same as the definitions of R₁ to R₃ except for the proviso.

6. The material for organic electroluminescence devices according to claim 2, wherein at least one of R₇, R₈ and R₂₀ to R₂₄ of the formula 2 is a group selected from the group consisting of a substituted or non-substituted 9-carbazolyl group, a substituted or non-substituted dibenzofuranyl group, a substituted or non-substituted azacarbazolyl group having 2 to 5 nitrogen atoms and a substituted or non-substituted dibenzothiophenyl group.

7. The material for organic electroluminescence devices according to claim 3, wherein at least one of R₇, R₉ and R₂₀ to R₂₄ of the formula 3 is a group selected from the group consisting of a substituted or non-substituted 9-carbazolyl group, a substituted or non-substituted dibenzofuranyl group, a substituted or non-substituted azacarbazolyl group having 2 to 5 nitrogen atoms and a substituted or non-substituted dibenzothiophenyl group.

8. The material for organic electroluminescence devices according to claim 4, wherein at least one of R₇ and R₂₁ to R₂₃ of the formula 4 is a group selected from the group consisting of a substituted or non-substituted 9-carbazolyl group, a substituted or non-substituted dibenzofuranyl group, a substituted or non-substituted azacarbazolyl group having 2 to 5 nitrogen atoms and a substituted or non-substituted dibenzothiophenyl group.

9. The material for organic electroluminescence devices according to claim 5, wherein at least one of R₇, R₈, R₂₀ and R₂₂ to R₂₉ of the formula 5 is a group selected from the group consisting of a substituted or non-substituted 9-carbazolyl group, a substituted or non-substituted dibenzofuranyl group, a substituted or non-substituted azacarbazolyl group having 2 to 5 nitrogen atoms and a substituted or non-substituted dibenzothiophenyl group.

10. The material for organic electroluminescence devices according to claim 1, wherein the compound represented by the formula 1 has a triplet energy gap of 2.2 to 3.2 eV.

11. An organic electroluminescence device which comprises a cathode, an anode and an organic thin film layer having one or more layers, the organic thin film layer being interposed between the cathode and the anode, at least one of the layers of the organic thin film being a light emitting layer which comprises a host material for use in combination with at least one phosphorescent metal complex, and at least one layer of the organic thin film containing the material for organic electroluminescence devices as defined in claim 1.

12. The organic electroluminescence device according to claim 11, wherein the host material contained in the light emitting layer is the material for organic electroluminescence devices.

13. The organic electroluminescence device according to claim 11, wherein the light emitting layer comprises the host material and a phosphorescent material and the host material is the material for organic electroluminescence devices.

14. The organic electroluminescence device according to claim 13, wherein the phosphorescent material is a compound containing iridium (Ir), osmium (Os) or platinum (Pt).

15. The organic electroluminescence device according to claim 13, wherein the light emitting layer contains a metal complex which emits blue light having a maximum peak wavelength of 500 nm or less.

16. The organic electroluminescence device according to claim 11, wherein at least one layer of the organic thin film layer is an electron injecting layer maily comprising a nitrogen-containing cyclic derivative which is different from the material for organic electroluminescence devices.

17. The organic electroluminescence device according to claim 11, wherein at least one layer of the organic thin film layer is a hole transporting layer which comprises the material for organic electroluminescence devices.

18. The organic electroluminescence device according to claim 11, which further comprises a reducing dopant at an interface between the cathode and the organic thin film layer.