COMPOSITION AND LIGHT-EMITTING ELEMENT USING THE COMPOSITION
Disclosed is a composition comprising a compound having a saturated heterocyclic structure, in which the number of ring-constituting members containing a nitrogen atom is 5 or more, and a phosphorescent compound.
1 . A composition comprising: a compound having a saturated heterocyclic structure, the ring including a nitrogen atom and the constituent members of the ring being 5 or more, and a phosphorescent compound.
2 . The composition according to claim 1 , wherein the compound having a saturated heterocyclic structure is a compound having a residue of a compound represented by a formula selected from the group consisting of formulas (1-1), (1-2), (1-3), (2-1), (2-2), (2-3) and (2-4) given below:
wherein R* each represents a hydrogen atom or a substituent or two R* bound to the same carbon atom integrally represent ═O; and a plurality of R* may be the same or different.
3 . The composition according to claim 2 , wherein the compound having a saturated heterocyclic structure is a compound represented by formula (3) given below or a compound having a residue the foregoing compound.
wherein HT represents a residue of a compound represented by the above formula (1-1), (1-2), (1-3), (2-1), (2-2), (2-3) or (2-4); n is an integer of 1 to 5; when n is 2 or more, a plurality of HT may be the same or different; Y′ and Y 2 each independently represent —C(R a )(R b )—, —N(R c )—, —O—, —Si(R d )(R e )—, —P(R f )—, —S—, —C(═O)— or —C(R g )═C(R h )—; R a , R b , R c , R d , R e , R f , R g and R h each independently represent a hydrogen atom or a substituent; m 1 and m 2 are each independently an integer of 0 to 5; when m 1 is 2 or more, a plurality of Y 1 may be the same or different; when m 2 is 2 or more, a plurality of Y 2 may be the same or different; ET 1 and ET 2 each independently represent an aryl group that may have a substituent or a heteroaryl group that may have a substituent.
4 . The composition according to claim 3 , wherein at least one of the ET 1 and ET 2 is a heteroaryl group that may have a substituent.
5 . The composition according to claim 4 , wherein the heteroaryl group that may have a substituent is a heteroaryl group substituted by an alkyl group, an alkoxy group, an aryl group that may have a substituent or a heteroaryl group that may have a substituent.
6 . The composition according to claim 5 , wherein the heteroaryl group that may have a substituent is a heteroaryl group substituted by an alkyl group having 3 to 10 carbon atoms, an alkoxy group having 3 to 10 carbon atoms, an aryl group substituted by an alkyl group having 3 to 10 carbon atoms or an alkoxy group having 3 to 10 carbon atoms, or an alkyl group having 3 to 10 carbon atoms or an alkoxy group having 3 to 10 carbon atoms.
7 . The composition according to claim 1 , wherein the lowest triplet excitation energy value of the compound having a saturated heterocyclic structure as calculated by a computational scientific approach is 3.0 eV or more.
8 . The composition according to claim 1 , wherein the absolute value of a lowest unoccupied molecular orbital energy level of the compound having a saturated heterocyclic structure as calculated by a computational scientific approach is 1.5 eV or more.
9 . The composition according to claim 1 , wherein the absolute value of a highest occupied molecular orbital energy level of the compound having a saturated heterocyclic structure as calculated by a computational scientific approach is 6.0 eV or less.
10 . The composition according to claim 3 , wherein in a compound represented by the above formula (3) or a compound containing a residue of the foregoing compound, groups represented by ET 1 and ET 2 bind to a partial structure having at least two π-conjugated electrons, dihedral angles between the groups represented by ET 1 and ET 2 and the partial structure are 20° or more.
11 . The composition according to claim 1 , wherein the lowest triplet excitation energy value (ETP) of the compound having a saturated heterocyclic structure and the lowest triplet excitation energy value (ETT) of the phosphorescent compound satisfy the expression given below:
ETP>ETT (eV).
12 . The composition according to claim 2 , wherein a compound having a residue of a compound represented by the above formula (1-1), (1-2), (1-3), (2-1), (2-2), (2-3) or (2-4) as a repeating unit is a polymer compound.
13 . A polymer compound having a residue of a compound represented by a formula selected from the group consisting of formulas (1-1), (1-2), (1-3), (2-1), (2-2), (2-3) and (2-4) given below and a residue of the phosphorescent compound.
wherein R* each represents a hydrogen atom or a substituent or two R* bound to the same carbon atom integrally represent ═O; and a plurality of R* may be the same or different.
14 . A film prepared by using the composition according to claim 1 .
15 . A light-emitting device prepared by using the composition according to claim 1 .
16 . A planar light source comprising the light-emitting device according to claim 15 .
17 . A display apparatus comprising the light-emitting device according to claim 15 .
18 . A light comprising the light-emitting device according to claim 15 .
19 . A film prepared by using the polymer compound according to claim 13 .
20 . A light-emitting device prepared by using the polymer compound according to claim 13 .