Organic electroluminescent element emitting light at high luminous efficiency and electronic device

Abstract

An organic electroluminescence device includes: a first emitting layer disposed between an anode and a cathode; a second emitting layer disposed between the first emitting layer and the cathode; and an electron blocking layer disposed between the first emitting layer and the anode, in which the first emitting layer and the second emitting layer are in direct contact with each other; the first emitting layer and the electron blocking layer are in direct contact with each other; the first emitting layer includes a first compound represented by a formula (1) below; the first compound includes at least one group represented by a formula (11) below; the second emitting layer includes a second compound represented by a formula (2); the electron blocking layer includes a third compound; and the third compound satisfies a formula (M1) below.

What is claimed is: 
     
         1 . An organic electroluminescence device comprising:
 an anode;   a cathode;   a first emitting layer and a second emitting layer disposed between the anode and the cathode; and   an electron transporting layer disposed between the cathode and the first and second emitting layers, wherein   the electron transporting layer comprises a compound represented by a formula (5A) below,   the first emitting layer comprises a first host material,   the second emitting layer comprises a second host material,   the first host material is different from the second host material,   the first emitting layer at least comprises a compound that emits light having a maximum peak wavelength of 500 nm or less,   the second emitting layer at least comprises a compound that emits light having a maximum peak wavelength of 500 nm or less,   the compound that emits light having the maximum peak wavelength of 500 nm or less and is contained in the first emitting layer and the compound that emits light having the maximum peak wavelength of 500 nm or less and is contained in the second emitting layer are mutually the same or different,   a triplet energy T 1 (H1) of the first host material and a triplet energy T 1 (H2) of the second host material satisfy a relationship of a numerical formula (Numerical Formula 1A) below,   
       
         
           
           
               
               
           
         
       
       where, in the formula (5A):
 X 51 , X 52  and X 53  are each independently a nitrogen atom or CR 5 ; 
 at least one of X 51 , X 52 , and X 53  is a nitrogen atom; 
 R 5  is a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R 901 )(R 902 )(R 903 ), a group represented by —O—(R 904 ), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having to 50 ring atoms; 
 R 901  to R 904  are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; 
 when a plurality of R 901  are present, the plurality of R 901  are mutually the same or different; 
 when a plurality of R 902  are present, the plurality of R 902  are mutually the same or different; 
 when a plurality of R 903  are present, the plurality of R 903  are mutually the same or different; and 
 when a plurality of R 904  are present, the plurality of R 904  are mutually the same or different; 
 Ax is a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 13 ring atoms; 
 Bx is a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 13 ring atoms; 
 L 5  is a single bond, a substituted or unsubstituted (n+1)-valent aromatic hydrocarbon ring group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted (n+1)-valent heterocyclic group having 5 to 13 ring atoms; 
 n is 1, 2, or 3, when n is 2 or 3, L 5  is not a single bond; 
 Cx is each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 60 ring atoms; and 
 when a plurality of Cx are present, the plurality of Cx are mutually the same or different. 
 
     
     
         2 . The organic electroluminescence device according to  claim 1 , wherein the first emitting layer and the second emitting layer are in direct contact with each other. 
     
     
         3 . The organic electroluminescence device according to  claim 1 , wherein the second emitting layer is disposed between the first emitting layer and the cathode. 
     
     
         4 . The organic electroluminescence device according to  claim 1 , wherein
 the first host material comprises, in a molecule, a linking structure comprising a benzene ring and a naphthalene ring linked to each other with a single bond,   the benzene ring and the naphthalene ring in the linking structure are each independently fused or not fused with a further monocyclic ring or fused ring, and   the benzene ring and the naphthalene ring in the linking structure are further linked to each other by cross-linking at at least one site other than the single bond.   
     
     
         5 . The organic electroluminescence device according to  claim 4 , wherein the cross-linking comprises a double bond. 
     
     
         6 . The organic electroluminescence device according to  claim 1 , wherein
 the first host material comprises, in a molecule, a biphenyl structure in which a first benzene ring and a second benzene ring are linked to each other with a single bond, and   the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by cross-linking at at least one site other than the single bond.   
     
     
         7 . The organic electroluminescence device according to  claim 6 , wherein the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by the cross-linking at at least one site other than the single bond. 
     
     
         8 . The organic electroluminescence device according to  claim 6 , wherein the cross-linking comprises a double bond. 
     
     
         9 . The organic electroluminescence device according to  claim 6 , wherein
 the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by the cross-linking at two sites other than the single bond, and   the cross-linking comprises no double bond.   
     
     
         10 . An organic electroluminescence device comprising:
 an anode;   a cathode;   a first emitting layer and a second emitting layer disposed between the anode and the cathode; and   an electron transporting layer disposed between the cathode and the first and second emitting layers, wherein   the electron transporting layer comprises a compound represented by a formula (5A) below,   the first emitting layer comprises a first host material in a form of a first compound represented by a formula (1) below,   the first compound comprises at least one group represented by a formula (11) below, and   the second emitting layer comprises a second host material in a form of a second compound represented by a formula (2) below,   
       
         
           
           
               
               
           
         
       
       where, in the formula (5A):
 X 51 , X 52  and X 53  are each independently a nitrogen atom or CR 5 ; 
 at least one of X 51 , X 52 , and X 53  is a nitrogen atom; 
 R 5  is a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R 901 )(R 902 )(R 903 ), a group represented by —O—(R 904 ), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having to 50 ring atoms; 
 R 901  to R 904  are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; 
 when a plurality of R 901  are present, the plurality of R 901  are mutually the same or different; 
 when a plurality of R 902  are present, the plurality of R 902  are mutually the same or different; 
 when a plurality of R 903  are present, the plurality of R 903  are mutually the same or different; and 
 when a plurality of R 904  are present, the plurality of R 904  are mutually the same or different; 
 Ax is a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 13 ring atoms; 
 Bx is a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 13 ring atoms; 
 L 5  is a single bond, a substituted or unsubstituted (n+1)-valent aromatic hydrocarbon ring group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted (n+1)-valent heterocyclic group having 5 to 13 ring atoms; 
 n is 1, 2, or 3, when n is 2 or 3, L 5  is not a single bond; 
 Cx is each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 60 ring atoms; and 
 when a plurality of Cx are present, the plurality of Cx are mutually the same or different, 
 
       
         
           
           
               
               
           
         
       
       where, in the formula (1):
 R 101  to R 110  are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R 901 )(R 902 )(R 903 ), a group represented by —O—(R 904 ), a group represented by —S—(R 905 ), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R 801 , a group represented by —COOR 802 , a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or the group represented by the formula (11); 
 at least one of R 101  to R 110  is the group represented by the formula (11); 
 when a plurality of groups represented by the formula (11) are present, the plurality of groups represented by the formula (11) are mutually the same or different; 
 L 101  is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms; 
 Ar 101  is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; 
 mx is 0, 1, 2, 3, 4 or 5; 
 when two or more L 101  are present, the two or more L 101  are mutually the same or different; 
 when two or more Ar 101  are present, the two or more Ar 101  are mutually the same or different; and 
 * in the formula (11) represents a bonding position to a pyrene ring represented by the formula (1); 
 
       
         
           
           
               
               
           
         
       
       where, in the formula (2):
 R 201  to R 208  are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R 901 )(R 902 )(R 903 ), a group represented by —O—(R 904 ), a group represented by —S—(R 905 ), a group represented by —N(R 906 )(R 907 ), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R 801 , a group represented by —COOR 802 , a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; 
 L 201  to L 202  are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms; 
 Ar 201  and Ar 202  are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; 
 in the first compound represented by the formula (1) and the second compound represented by the formula (2), R 901 , R 902 , R 903 , R 904 , R 905 , R 906 , R 907 , 
 R 801  and R 802  are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; 
 when a plurality of R 901  are present, the plurality of R 901  are mutually the same or different; 
 when a plurality of R 902  are present, the plurality of R 902  are mutually the same or different; 
 when a plurality of R 903  are present, the plurality of R 903  are mutually the same or different; 
 when a plurality of R 904  are present, the plurality of R 904  are mutually the same or different; 
 when a plurality of R 905  are present, the plurality of R 905  are mutually the same or different; 
 when a plurality of R 906  are present, the plurality of R 906  are mutually the same or different; 
 when a plurality of R 907  are present, the plurality of R 907  are mutually the same or different; 
 when a plurality of R 801  are present, the plurality of R 801  are mutually the same or different; and 
 when a plurality of R 802  are present, the plurality of R 802  are mutually the same or different. 
 
     
     
         11 . The organic electroluminescence device according to  claim 1 , wherein the compound represented by the formula (5A) is a compound represented by a formula (50A) below, 
       
         
           
           
               
               
           
         
         where, in the formula (50A), Ax, Bx, Cx, L 5  and n represent the same as Ax, Bx, Cx, L 5  and n defined in the formula (5A). 
       
     
     
         12 . The organic electroluminescence device according to  claim 1 , wherein a substituent for a “substituted or unsubstituted” group is at least one group selected from the group consisting of an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 ring carbon atoms, and a heterocyclic group having 5 to 18 ring atoms. 
     
     
         13 . The organic electroluminescence device according to  claim 1 , wherein a substituent for a “substituted or unsubstituted” group is an alkyl group having 1 to 5 carbon atoms. 
     
     
         14 . The organic electroluminescence device according to  claim 10 , wherein in the first compound and the second compound, the groups specified to be “substituted or unsubstituted” are each an “unsubstituted” group. 
     
     
         15 . An electronic device comprising the organic electroluminescence device according to  claim 1 . 
     
     
         16 . The organic electroluminescence device according to  claim 10 , wherein the first emitting layer and the second emitting layer are in direct contact with each other. 
     
     
         17 . The organic electroluminescence device according to  claim 10 , wherein the second emitting layer is disposed between the first emitting layer and the cathode. 
     
     
         18 . The organic electroluminescence device according to  claim 1 , wherein the first emitting layer and the second emitting layer contain no phosphorescent material. 
     
     
         19 . The organic electroluminescence device according to  claim 10 , wherein the first emitting layer and the second emitting layer contain no phosphorescent material. 
     
     
         20 . The organic electroluminescence device according to  claim 1 , wherein
 the compound that is contained in the first emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a compound that emits light having a maximum peak wavelength of 480 nm or less; and   the compound that is contained in the second emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a compound that emits light having a maximum peak wavelength of 480 nm or less.   
     
     
         21 . The organic electroluminescence device according to  claim 1 , wherein
 the compound that is contained in the first emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a fifth compound that fluoresces; and   the compound that is contained in the second emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a fourth compound that fluoresces.   
     
     
         22 . The organic electroluminescence device according to  claim 10 , wherein
 the compound that is contained in the first emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a compound that emits light having a maximum peak wavelength of 480 nm or less; and   the compound that is contained in the second emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a compound that emits light having a maximum peak wavelength of 480 nm or less.   
     
     
         23 . The organic electroluminescence device according to  claim 10 , wherein
 the compound that is contained in the first emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a fifth compound that fluoresces; and   the compound that is contained in the second emitting layer and emits light having the maximum peak wavelength of 500 nm or less is a fourth compound that fluoresces.