Material for organic electroluminescence device and organic electroluminescence device

1. A material for an organic electroluminescence device, comprising:

a phosphorescent metal complex represented by the following formula (A10):

in formula (A10),

each of R 1a to R 1h independently represents

a hydrogen atom,

a fluorine atom,

a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an isobutyl group, a neopentyl group, an n-hexyl group,

a phenyl group or a naphthyl group, each of which may be substituted with a methyl group, an isopropyl group or a neopentyl group,

a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an isobutyl group, a neopentyl group or an n-hexyl group, each of which is substituted with 1 or more and not more than 10 fluorine atoms, or

a phenyl group or a naphthyl group, each of which may be substituted with a methyl group, an isopropyl group or a neopentyl group, each of which is substituted with 1 or more and not more than 10 fluorine atoms;

R 1a to R 1h may be bonded to each other to form a ring;

X-Y represents a monoanionic bidentate ligand represented by the following I-1, I-4 or I-5; and

n represents 2 or 3:

wherein

each of Rx, Ry and Rz independently represents a hydrogen atom, a fluorine atom, an alkyl group having not more than 6 carbon atoms, a phenyl group, an alkyl group having not more than 6 carbon atoms and substituted with one or more fluorine atoms, or a phenyl group substituted with one or more fluorine atoms,

provided that a content of a fluorine atom in the phosphorescent metal complex is 7% by mass or more.

2. The material for an organic electroluminescence device according to claim 1 ,

wherein the phosphorescent metal complex represented by the formula (A10) is a phosphorescent metal complex represented by the following formula (A10-1):

in formula (A10-1),

R 1a to R 1h are synonymous with R 1a to R 1h in the formula (A10).

3. The material for an organic electroluminescence device according to claim 1 ,

wherein the phosphorescent metal complex represented by the formula (A10) is a phosphorescent metal complex represented by the following formula (A20):

in formula (A20),

each of R 1a to R 1c independently represents

a hydrogen atom,

a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an isobutyl group, a neopentyl group, an n-hexyl group, or

a phenyl group or a naphthyl group, each of which may be substituted with a methyl group, an isopropyl group or a neopentyl group;

R 1a to R 1h may be bonded to each other to form a ring;

n 1 represents 2; and

X-Y, Rx, Ry and Rz are synonymous with X-Y, Rx, Ry and Rz in the formula (A10).

4. An organic electroluminescence device, comprising:

a substrate having thereon a pair of electrodes; and

at least one layer of organic layers including a light emitting layer between the electrodes,

wherein the material for an organic electroluminescence device according to claim 1 is contained in at least one layer of the organic layers.

5. The organic electroluminescence device according to claim 4 ,

wherein the material for an organic electroluminescence device is contained in the light emitting layer.

6. A light emitting unit that uses the organic electroluminescence device according to claim 4 .

7. A display unit that uses the organic electroluminescence device according to claim 4 .

8. An illumination unit that uses the organic electroluminescence device according to claim 4 .