Material for organic electroluminescence element, and organic electroluminescence element using the material

Abstract

An organic electroluminescence device comprising a compound having a specific structure having a heteroatom and an organic electroluminescence device which comprises a cathode, an anode and an organic thin film layer which comprises at least one layer comprising at least a light emitting layer and is disposed between the cathode and the anode, wherein at least one layer in the organic thin film layer comprises the above compound. The device provides excellent efficiency of light emission, forms no defects in pixels, exhibits excellent heat resistance and has a long life.

1 . A material for organic electroluminescence devices which comprises a compound represented by following general formula (1): 
       
         
           
           
               
               
           
         
       
       wherein R 1  to R 8  each independently represent hydrogen atom, a halogen atom, an alkyl group having 1 to 40 carbon atoms which may have substituents, a heterocyclic group having 3 to 20 carbon atoms which may have substituents, an alkoxyl group having 1 to 40 carbon atoms which may have substituents, a non-condensed aryl group having 6 to 40 carbon atoms which may have substituents, a condensed aryl group having 6 to 12 carbon atoms which may have substituents, an aryloxyl group having 6 to 20 carbon atoms which may have substituents, an aralkyl group having 7 to 20 carbon atoms which may have substituents, an alkenyl group having 2 to 40 carbon atoms which may have substituents, an alkylamino group having 1 to 40 carbon atoms which may have substituents, an aralkylamino group having 7 to 60 carbon atoms which may have substituents, an alkylsilyl group having 3 to 20 carbon atoms which may have substituents, an arylsilyl group having 8 to 40 carbon atoms which may have substituents, an aralkylsilyl group having 8 to 40 carbon atoms which may have substituents, an alkylgermanium group having 3 to 20 carbon atoms which may have substituents, an arylgermanium group having 8 to 40 carbon atoms which may have substituents, an aralkylgermanium group having 8 to 40 carbon atoms which may have substituents, a ketoaryl group having 7 to 40 carbon atoms which may have substituents, a halogenated alkyl group having 1 to 40 carbon atoms which may have substituents, cyano group or a structure represented by following general formula (a), and at least one of R 1  to R 8  has a structure represented by general formula (a): 
       
         
           
           
               
               
           
         
       
       in general formula (a), L representing a single bond, an alkylene group having 1 to 10 carbon atoms which may have substituents, a non-condensed arylene group having 6 to 40 carbon atoms which may have substituents, a condensed arylene group having 6 to 12 carbon atoms which may have substituents or a divalent aromatic heterocyclic group having 3 to 40 carbon atoms which may have substituents, Y 1  to Y 3  each independently representing an alkyl group having 1 to 10 carbon atoms which may have substituents, an aryl group having 6 to 20 carbon atoms which may have substituents or an aromatic heterocyclic group having 6 to 30 carbon atoms which may have substituents, and Z representing silicon atom or germanium atom; and
 X represents sulfur atom, oxygen atom, a substituted silicon atom represented by SiR a R b  or a substituted germanium atom represented by GeR c R d , R a , R b , R c  and R d  each independently representing an alkyl group having 1 to 40 carbon atoms which may have substituents or an aryl group having 6 to 20 carbon atoms which may have substituents. 
 
     
     
         2 . A material for organic electroluminescence devices which comprises a compound represented by following general formula (2): 
       
         
           
           
               
               
           
         
       
       wherein R 11  to R 14  and R each independently represent hydrogen atom, a halogen atom, an alkyl group having 1 to 40 carbon atoms which may have substituents, a heterocyclic group having 3 to 20 carbon atoms which may have substituents, an alkoxyl group having 1 to 40 carbon atoms which may have substituents, a non-condensed aryl group having 6 to 40 carbon atoms which may have substituents, a condensed aryl group having 6 to 12 carbon atoms which may have substituents, an aryloxyl group having 6 to 20 carbon atoms which may have substituents, an aralkyl group having 7 to 20 carbon atoms which may have substituents, an alkenyl group having 2 to 40 carbon atoms which may have substituents, an alkylamino group having 1 to 40 carbon atoms which may have substituents, an aralkylamino group having 7 to 60 carbon atoms which may have substituents, an alkylsilyl group having 3 to 20 carbon atoms which may have substituents, an arylsilyl group having 8 to 40 carbon atoms which may have substituents, an aralkylsilyl group having 8 to 40 carbon atoms which may have substituents, an alkylgermanium group having 3 to 20 carbon atoms which may have substituents, an arylgermanium group having 8 to 40 carbon atoms which may have substituents, an aralkylgermanium group having 8 to 40 carbon atoms which may have substituents, a ketoaryl group having 7 to 40 carbon atoms which may have substituents, a halogenated alkyl group having 1 to 40 carbon atoms which may have substituents or cyano group;
 X represents sulfur atom, oxygen atom, a substituted silicon atom represented by SiR a R b  or a substituted germanium atom represented by GeR c R d , R a , R b , R c  and R d  each independently representing an alkyl group having 1 to 40 carbon atom which may have substituents or an aryl group having 6 to 20 carbon atoms which may have substituents; 
 L represents a single bond, an alkylene group having 1 to 10 carbon atoms which may have substituents, a non-condensed arylene group having 6 to 40 carbon atoms which may have substituents, a condensed arylene group having 6 to 12 carbon atoms which may have substituents or a divalent aromatic heterocyclic group having 3 to 40 carbon atoms which may have substituents; 
 Y represents an alkyl group having 1 to 10 carbon atoms which may have substituents, an aryl group having 6 to 20 carbon atoms which may have substituents or an aromatic heterocyclic group having 6 to 30 carbon atoms which may have substituents and, when a plurality of groups represented by Y are present, Y may represent a same group or different groups; 
 Z represents silicon atom or germanium atom; and 
 n represents an integer of 1 to 4. 
 
     
     
         3 . A material for organic electroluminescence devices according to  claim 2 , which comprises a compound represented by one of following general formulae (3) and (4): 
       
         
           
           
               
               
           
         
         wherein R 11  to R 17  are as defined for R 11  to R 14  and R in general formula (2), and L, X, Z, Y and n are as defined in general formula (2). 
       
     
     
         4 . An organic electroluminescence device which comprises a cathode, an anode and an organic thin film layer which comprises at least one layer comprising at least a light emitting layer and is disposed between the cathode and the anode, wherein at least one layer in the organic thin film layer comprises the material for organic electroluminescence devices described in any one of  claims 1  to  3 . 
     
     
         5 . An organic electroluminescence device according to  claim 4 , wherein the light emitting layer comprises the material for organic electroluminescence devices as a host material. 
     
     
         6 . An organic electroluminescence device according to  claim 4 , wherein the light emitting layer comprises a host material and a phosphorescent light emitting material, and the host material is the material for organic electroluminescence devices described in any one of  claims 1  to  3 . 
     
     
         7 . An organic electroluminescence device according to  claim 4 , wherein the light emitting layer comprises a host material and a phosphorescent light emitting material, and the phosphorescent light emitting material is a compound having a metal selected from iridium (Ir), osmium (Os) and platinum (Pt). 
     
     
         8 . An organic electroluminescence device according to  claim 4 , wherein the light emitting layer comprises a host material and a phosphorescent light emitting material, and the phosphorescent light emitting material is a light emitting material having a metal-carbene carbon bond. 
     
     
         9 . An organic electroluminescence device according to  claim 4 , wherein the light emitting layer comprises a metal complex compound emitting bluish light which exhibits a maximum luminance at a wavelength of 500 nm or smaller. 
     
     
         10 . An organic electroluminescence device according to  claim 4 , which comprises an electron injecting layer disposed between the light emitting layer and the cathode, and the electron injecting layer comprises a cyclic derivative having nitrogen atom as a main component thereof. 
     
     
         11 . An organic electroluminescence device according to  claim 4 , which comprises a hole transporting layer, and the hole transporting layer comprises the material for organic electroluminescence devices. 
     
     
         12 . An organic electroluminescence device according to  claim 4 , which comprises at least one of an electron transporting layer and a hole barrier layer, and at least one of the electron transporting layer and the hole barrier layer comprises the material for organic electroluminescence devices. 
     
     
         13 . An organic electroluminescence device according to  claim 4 , wherein a reducing dopant is added at an interfacial region between the cathode and the organic thin film layer.