Thin film and organic electroluminescent element

A thin film containing a light-emitting metal complex and two kinds of hosts, wherein

• the light-emitting metal complex is represented by the following General Formula (1) and satisfies Equation (1), and
• the two kinds of hosts are combined to form an excited complex.
• [In General Formula (1), M represents Ir or Pt;
• and A1, A2, B1, B2 respectively represent a carbon atom or a nitrogen atom;
• ring Z1 represents a 6-membered aromatic hydrocarbon ring formed with A1 and A2, a 5- or a 6-membered aromatic heterocyclic ring formed with A1 and A2, or an aromatic fused ring including at least one of the aromatic hydrocarbon ring and the aromatic heterocyclic rings;
• one of a bond between A1 and M and a bond between B1 and M represents a coordinate bond, and the other is a covalent bond;
• ring Z1 and ring Z2 may independently have a substituent, but have at least one substituent represented by the following General Formula (2);
• a fused ring structure may be formed by a substituent of the ring Z1 and a substituent of the ring Z2 being bound to each other, or ligands represented by the ring Z1 and the ring Z2 may be bound to each other;
• L represents a monoanionic bidentate ligand coordinated with M, and may have a substituent;
• m represents an integer from 0 to 2, and n represents an integer from 1 to 3;
• when M is Ir, m+n is 3;
• when M is Pt, m+n is 2;
• when m or n is 2 or more, L(s) or the ligands represented by the ring Z1 and the ring Z2 may be the same or different respectively;
• and L and the ligand represented by the ring Z1 and the ring Z2 may be bound to each other.]
• *-L′-(CR2)n′-A General Formula (2)
• [In General Formula (2), * represents a binding position on the ring Z1 or the ring Z2 in General Formula (1);
• L′ represents a single bond or a linker;
• R represents a hydrogen atom or a substituent;
• n′ represents an integer of 3 or more;
• a plurality of R(s) may be the same or different;
• and A represents a hydrogen atom or a substituent.]
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• [In Equation (1), Van represents a molecular volume of a structure including substituents bound to the ring Z1 and the ring Z2, wherein it is assumed that n=3 and m=0 when M is Ir, and n=2 and m=0 when M is Pt;
• and Vcore represents a molecular volume of a structure where the substituents bound to the ring Z1 and the ring Z2 in the structure having the molecular volume of Vall are replaced by hydrogen atoms. Note, when there are a plurality of ligands represented by the ring Z1 and the ring Z2, Vall and Vcore satisfy Equation (1) in all the cases represented by the above described assumption.]

A thin film containing a light-emitting metal complex and a host, wherein

• the light-emitting metal complex is represented by any one of the following General Formulae (3)˜(5) and satisfies the following Equation (1);
• and
• the host is a non-metallic organic compound showing phosphorescence at room temperature, a compound showing thermally activated delayed fluorescence, or a compound expressing an inverse intersystem crossing phenomenon between a singlet excited state showing a level higher than a lowest singlet excited state and a triplet excited state showing a level higher than a lowest triplet excited state.
• [In General Formulae (3)˜(5), M represents Ir or Pt;
• A1˜A3 and B1˜B4 respectively represent a carbon atom or a nitrogen atom;
• one of a bond between A1 and M and a bond between B1 and M represents a coordinate bond, and the other is a covalent bond.
• L represents a monoanionic bidentate ligand coordinated with M, and may have a substituent;
• m represents an integer from 0 to 2, and n represents an integer from 1 to 3;
• when M is Ir, m+n is 3;
• when M is Pt, m+n is 2;
• when m or n is 2 or more, ligands represented by ring Z3 and ring Z4, ligands represented by ring Z5 and ring Z6, ligands represented by ring Z7 and ring Z8, or L(s) may be the same or different respectively, and L and those ligands may be bound to each other.
• In General Formula (3), the ring Z3 represents a 5-membered aromatic heterocyclic ring formed with A1 and A2, or an aromatic fused ring including the 5-membered aromatic heterocyclic ring;
• the ring Z4 represents a 5-membered aromatic heterocyclic ring formed with B1˜B3, or an aromatic fused ring including the 5-membered aromatic heterocyclic ring;
• R1 represents a substituent having 2 or more carbon atoms;
• the ring Z3 and the ring Z4 may include a substituent besides R1;
• and
• a fused ring structure may be formed by a substituent of the ring Z3 and a substituent of the ring Z4 being bound to each other;
• and ligands represented by the ring Z3 and the ring Z4 may be bound to each other.
• In General Formula (4), the ring Z5 represents a 6-membered aromatic hydrocarbon ring formed with A1˜A3, a 6-membered aromatic heterocyclic ring formed with A1˜A3, or an aromatic fused ring including at least one of the 6-membered aromatic hydrocarbon and heterocyclic rings;
• the ring Z6 represents a 5-membered aromatic heterocyclic ring formed with B1˜B3, or an aromatic fused ring including the 5-membered aromatic heterocyclic ring;
• R2 and R3 independently represent a hydrogen atom or a substituent, and at least either of R2 or R3 represents a substituent having 2 or more carbon atoms;
• the ring Z5 and the ring Z6 may have a substituent besides R2 and R3;
• and
• a fused ring structure may be formed by a substituent of the ring Z5 and a substituent of the ring Z6 being bound to each other, and ligands represented by the ring Z5 and the ring Z6 may be bound to each other.
• In General Formula (5), the ring Z7 represents a 6-membered aromatic hydrocarbon ring formed with A1 and A2, a 6-membered aromatic heterocyclic ring formed with A1 and A2, or an aromatic fused ring including at least one of the 6-membered aromatic hydrocarbon and heterocyclic rings;
• the ring Z8 represents a 6-membered aromatic hydrocarbon ring formed with B1˜B4, a 6-membered aromatic heterocyclic ring formed with B1˜B4, or an aromatic fused ring including the 6-membered aromatic hydrocarbon and heterocyclic rings;
• R4 and R5 respectively represent a hydrogen atom or a substituent, and at least either of R4 or R5 represents a substituent having 2 or more carbon atoms;
• the ring Z7 and the ring Z8 may include a substituent besides R4 and R5;
• and
• a fused ring structure may be formed by a substituent of the ring Z7 and a substituent of the ring Z8 being bound to each other, and ligands represented by the ring Z7 and the ring Z8 may be bound to each other.
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• [In Equation (1), Vall represents a molecular volume of a structure including substituents bound to the rings Z3˜Z8, wherein it is assumed that n=3 and m=0 when M is Ir, and n=2 and m=0 when M is Pt;
• and Vcore represents a molecular volume of a structure where the substituents bound to the rings Z3˜Z8 in the structure having the molecular volume of Vall are replaced by hydrogen atoms;
• Note, when there are a plurality of ligands represented by the ring Z3 and the ring Z4, represented by the ring Z5 and the ring Z6, and represented by the ring Z7 and the ring Z8, Vall and Vcore satisfy Equation (1) in all the cases represented by the above described assumption.]

A thin film containing a light-emitting metal complex and two kinds of hosts, wherein

• the light-emitting metal complex is represented by any one of the following General Formulae (3)˜(5) and satisfies the following Equation (1), and
• the two kinds of hosts are combined to form an excited complex.
• [In General Formulae (3)˜(5), M represents Ir or Pt;
• A1˜A3 and B1˜B4 respectively represent a carbon atom or a nitrogen atom;
• one of a bond between A1 and M and a bond between B1 and M represents a coordinate bond, and the other represents a covalent bond;
• L represents a monoanionic bidentate ligand coordinated with M, and may have a substituent;
• and
• m represents an integer from 0 to 2, and n represents an integer from 1 to 3;
• when M is Ir, m+n is 3;
• when M is Pt, m+n is 2;
• when m or n is 2 or more, a ligand represented by ring Z3 and ring Z4, a ligand represented by ring Z5 and ring Z6, a ligand represented by ring Z7 and ring Z8, or L(s) may be the same or different respectively;
• and L and those ligands may be bound each other.
• In General Formula (3), the ring Z3 represents a 5-membered aromatic heterocyclic ring formed with A1 and A2, or an aromatic fused ring including the 5-membered aromatic heterocyclic ring;
• the ring Z4 represents a 5-membered aromatic heterocyclic ring formed with B1˜B3, or an aromatic fused ring including the 5-membered aromatic heterocyclic ring;
• R1 represents a substituent having 2 or more carbon atoms;
• the ring Z3 and the ring Z4 may include a substituent besides R1;
• a fused ring structure may be formed by a substituent of the ring Z5 and a substituent of the ring Z6 being bound each other;
• and ligands represented by the ring Z5 and the ring Z6 may be bound to each other;
• In General Formula (5), the ring Z7 represents a 6-membered aromatic hydrocarbon ring formed with A1 and A2, a 6-membered aromatic heterocyclic ring formed with A1 and A2, or an aromatic fused ring including at least one of the 6-membered aromatic hydrocarbon and heterocyclic rings;
• the ring Z8 represents a 6-membered aromatic hydrocarbon ring formed with B1˜B4, a 6-membered aromatic heterocyclic ring formed with B1˜B4, or an aromatic fused ring including the 6-membered aromatic hydrocarbon and heterocyclic rings;
• R4 and R5 respectively represent a hydrogen atom or a substituent, and at least either of R4 or R5 represents a substituent having 2 or more carbon atoms;
• the ring Z7 and the ring Z8 may include a substituent besides R4 and R5;
• and
• a fused ring structure may be formed by a substituent of the ring Z7 and a substituent of the ring Z8 being bound to each other;
• and ligands represented by the ring Z7 and the ring Z8 may be bound to each other.
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• [In Equation (1), Vall represents a molecular volume of a structure including substituents bound to the rings Z3˜Z8, wherein it is assumed that n=3 and m=0 when M is Ir, and n=2 and m=0 when M is Pt;
• Vcore represents a molecular volume of a structure where the substituents bound to the rings Z3˜Z8 in the structure having the molecular volume of Vall are replaced by hydrogen atoms;
• Note, when there are a plurality of ligands represented by the ring Z3 and the ring Z4, represented by the ring Z5 and the ring Z6, and represented by the ring Z7 and the ring Z8, Vall and Vcore satisfy Equation (1) in all the cases represented by the above described assumption.]