Benzotriazole compound-containing composition and light-emitting device using the composition

1. A composition comprising a compound having a benzotriazole ring structure and a phosphorescence-emitting compound,

wherein the compound having a benzotriazole ring structure has the lowest triplet excitation energy of 2.7 eV or larger calculated by a computational chemical approach and has an absolute value of the lowest unoccupied molecular orbital energy level of 2.0 eV or larger calculated by a computational chemical approach.

2. The composition according to claim 1 , wherein the compound having a benzotriazole ring structure has at least one benzotriazole ring structure selected from the following general formulas (1-1), (1-2), (1-3), (1-4), (2-1), (2-2), (2-3), (3-1), (3-2), (3-3), (3-4), (4-1) and (4-2):

wherein R and R 1 each independently represent a hydrogen atom or a monovalent substituent, and when a plurality of R or R 1 are present, they may be the same or different.

3. The composition according to claim 1 , wherein the lowest triplet excitation energy (ETP) of the compound having a benzotriazole ring structure satisfies, with a lowest triplet excitation energy (ETT) of the phosphorescence-emitting compound, the following formula:

ETT>ETP−0.5 (eV).

4. The composition according to claim 1 wherein the compound having a benzotriazole ring structure is a compound represented by the following general formula (A-1) or (A-2) or a compound having a residue thereof:

wherein bnztrzl represents a benzotriazole ring structure represented by the general formula (1-2), (1-3), (2-2), (3-1), (3-2), (3-3) or (4-2):

and R and R 1 each independently represent a hydrogen atom or a monovalent substituent, and when a plurality of R or R 1 are present, they may be the same or different;

when a plurality of bnztrzl are present, they may be the same or different; Y 1 represents—C(R a )(R b )—, —C(═O)—, —N(R c )—, —O—, —Si(R d )(R e )—, —P(R f )—, —S— or —S(═O) 2 —; n is an integer of 0 to 5;

Ar 1 represents an aryl group which may have a substituent or a monovalent heterocyclic group which may have a substituent; when a plurality of Y 1 are present, they may be the same or different; and R a to R f each independently represent a hydrogen atom or a monovalent substituent.

5. The composition according to claim 1 , wherein the compound having a benzotriazole ring structure is represented by the following general formula (6a), (6b) or (6c):

wherein bnztrzl represents a benzotriazole ring structure represented by the general formula (1-2), (1-3), (2-2), (3-1), (3-2), (3-3) or (4-2):

and R and R 1 each independently represent a hydrogen atom or a monovalent substituent, and when a plurality of R or R 1 are present, they may be the same or different; X

represents a m1-valent aromatic group which may have a substituent or a m1-valent aromatic heterocyclic group which may have a substituent; X′ represents a m3-valent aromatic group which may have a substituent or a m3-valent aromatic heterocyclic group which may have a substituent; Ar represents an arylene group which may have a substituent; Z represents a linking group; m1, m2 and m3 are each independently an integer of 2 to 8; when a plurality of Z are present, they may be the same or different; and a plurality of Ar or bnztrzl may be the same or different.

6. The composition according to claim 2 , wherein the compound having a benzotriazole ring structure has a benzotriazole ring structure represented by the general formula (1-1), (1-2), (1-3), (1-4), (2-1), (2-2), (2-3), (3-1), (3-2), (3-3), (3-4), (4-1) or (4-2) and a partial structure adjacent to the benzotriazole ring structure, the partial structure having at least two π-conjugated electrons, wherein the benzotriazole ring structure and the partial structure form a dihedral angle of 20° or larger therebetween.

7. The composition according to claim 2 , wherein at least one of the R and the R 1 is an alkyl group, an alkoxy group, an aryl group which may have a substituent or a heteroaryl group which may have a substituent.

8. The composition according to claim 2 , wherein at least one of the plurality of R and the plurality of R 1 is an alkyl group having 3 to 10 carbon atoms or an alkoxy group having 3 to 10 carbon atoms.

9. The composition according to claim 8 , wherein at least one of the R is a monovalent substituent having a total of three or more atoms exclusive of hydrogen atoms.

10. The composition according to claim 1 , wherein the compound having a benzotriazole ring structure is a polymer.

11. A polymer having a residue of a phosphorescence-emitting compound and a benzotriazole ring structure.

12. A light-emitting thin film using a composition according to claim 1 .

13. An organic semiconductor thin film using a composition according to claim 1 .

14. A light-emitting device using a composition according to claim 1 .

15. A planar light source comprising a light-emitting device according to claim 14 .

16. A segment display device comprising a light-emitting device according to claim 14 .

17. A dot matrix display device comprising a light-emitting device according to claim 14 .

18. A liquid-crystal display device comprising a light-emitting device according to claim 14 as a backlight.

19. Illumination comprising a light-emitting device according to claim 14 .