Material for organic electroluminescence devices and organic electroluminescence device using the material

Abstract

A material for organic electroluminescence devices comprising a compound in which a heterocyclic group having nitrogen is bonded to an arylcarbazolyl group or a carbazolylalkylene group and an organic electroluminescence device comprising an anode, a cathode and an organic thin film layer comprising at least one layer and disposed between the anode and the cathode, wherein at least one layer in the organic thin film layer comprises the material for organic electroluminescence devices described above. The material can provide an organic electroluminescence device emitting bluish light with a high purity of color. The organic electroluminescence device uses the material.

What is claimed is:  
     
         1 . A material for organic electroluminescence devices which comprises a compound represented by following general formula (1) or (2):  
       (Cz—) n A  (1) Cz(—A) m   (2)  
       wherein Cz represents a substituted or unsubstituted arylcarbazolyl group or carbazolylalkylene group, A represents a group represented by following general formula (A):  
       (M) p —(L) q —(M′) r   (A)  
       wherein M and M′ each independently represent a heteroaromatic ring having 2 to 40 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, M and M′ may represent a same ring or different rings, L represents a single bond, a substituted or unsubstituted aryl group or arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms or a substituted or unsubstituted heteroaromatic ring having 2 to 30 carbon atoms, p represents an integer of 0 to 2, q represents an integer of 1 or 2, r represents an integer of 0 to 2, and p+r represents an integer of 1 or greater; and n and m each represent an integer of 1 to 3.  
     
     
         2 . A material for organic electroluminescence devices according to  claim 1 , wherein 
 n=1 in general formula (1) and p=1 and r=0 in general formula (A);    in general formula (1), Cz represents a substituted or unsubstituted arylcarbazolyl group or carbazolylalkylene group; and    in general formula (A), M represents a heterocyclic six-membered or seven-membered ring having 4 or 5 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, a heterocyclic five-membered ring having 2 to 4 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, a heterocyclic ring having 8 to 11 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring or a substituted or unsubstituted imidazopyridinyl ring, and L represents a substituted or unsubstituted aryl group or arylene group having 6 to 30 carbon atoms or a substituted or unsubstituted heteroaromatic ring having 2 to 30 carbon atoms.    
     
     
         3 . A material for organic electroluminescence devices according to  claim 1 , wherein 
 n=2 in general formula (1) and p=1 and r=0 in general formula (A);    in general formula (1), Cz represents a substituted or unsubstituted arylcarbazolyl group or carbazolylalkylene group; and    in general formula (A), M represents a heterocyclic six-membered or seven-membered ring having 4 or 5 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, a heterocyclic five-membered ring having 2 to 4 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, a heterocyclic ring having 8 to 11 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring or a substituted or unsubstituted imidazopyridinyl ring, and L represents a substituted or unsubstituted aryl group or arylene group having 6 to 30 carbon atoms or a substituted or unsubstituted heteroaromatic ring having 2 to 30 carbon atoms.    
     
     
         4 . A material for organic electroluminescence devices according to  claim 1 , wherein 
 n=1 in general formula (1) and p=2 and r=0 in general formula (A);    in general formula (1), Cz represents a substituted or unsubstituted arylcarbazolyl group or carbazolylalkylene group; and    in general formula (A), M represents a heteroaromatic ring having 2 to 40 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, and L represents a substituted or unsubstituted aryl group or arylene group having 6 to 30 carbon atoms or a substituted or unsubstituted heteroaromatic ring having 2 to 30 carbon atoms.    
     
     
         5 . A material for organic electroluminescence devices according to  claim 1 , wherein 
 m=2 in general formula (2) and p=q=1 in general formula (A);    in general formula (2), Cz represents a substituted or unsubstituted arylcarbazolyl group or carbazolylalkylene group; and    in general formula (A), M and M′ each independently represent a heteroaromatic ring having 2 to 40 carbon atoms and nitrogen atom and forming a substituted or unsubstituted ring, and M and M′ may represent a same ring or different rings, and L represents a substituted or unsubstituted aryl group or arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 carbon atoms or a substituted or unsubstituted heteroaromatic ring having 2 to 30 carbon atoms.    
     
     
         6 . A material for organic electroluminescence devices according to  claim 1 , wherein Cz represents a substituted or unsubstituted arylcarbazolyl group.  
     
     
         7 . A material for organic electroluminescence devices according to  claim 6 , wherein Cz represents a substituted or unsubstituted phenylcarbazolyl group.  
     
     
         8 . A material for organic electroluminescence devices according to  claim 6 , wherein an aryl portion of the arylcarbazolyl group is substituted with carbazolyl group.  
     
     
         9 . A material for organic electroluminescence devices according to  claim 1 , wherein a triplet energy gap of a compound represented by general formula (1) or (2) is 2.5 to 3.3 eV.  
     
     
         10 . A material for organic electroluminescence devices according to  claim 1 , wherein a singlet energy gap of a compound represented by general formula (1) or (2) is 2.8 to 3.8 eV.  
     
     
         11 . An organic electroluminescence device comprising an anode, a cathode and an organic thin film layer comprising at least one layer and disposed between the anode and the cathode, wherein at least one layer in the organic thin film layer comprises a material for organic electroluminescence devices described in  claim 1 .  
     
     
         12 . An organic electroluminescence device comprising an anode, a cathode and an organic thin film layer comprising at least one layer and disposed between the anode and the cathode, wherein a light emitting layer comprises a material for organic electroluminescence devices described in  claim 1 .  
     
     
         13 . An organic electroluminescence device comprising an anode, a cathode and an organic thin film layer comprising at least one layer and disposed between the anode and the cathode, wherein an electron transporting layer comprises a material for organic electroluminescence devices described in  claim 1 .  
     
     
         14 . An organic electroluminescence device comprising an anode, a cathode and an organic thin film layer comprising at least one layer disposed between the anode and the cathode, wherein a hole transporting layer comprises a material for organic electroluminescence devices described in  claim 1   
     
     
         15 . An organic electroluminescence device according to  claim 11 , wherein the material for organic electroluminescence devices is an organic host material.  
     
     
         16 . An organic electroluminescence device according to  claim 11 , which comprises an inorganic compound layer disposed between at least one of the electrodes and the organic thin film layer.  
     
     
         17 . An organic electroluminescence device according to  claim 11 , which emits light by a multiplet excitation which is excitation to a triplet state or higher.  
     
     
         18 . An organic electroluminescence device according to  claim 11 , which emits bluish light.