Luminescent element

1. A light-emitting element, which comprises a substrate having provided thereon a pair of opposed electrodes between which are provided a light-emitting layer containing at least one light-emitting material selected from the compounds represented by the following general formula (I) and a host material, and

which comprises an organic membrane having a larger ionization potential than that of the host material between the light-emitting layer and a cathode, the organic membrane being in contact with the light-emitting layer:

wherein R 1 , R 3 , R 4 and R 5 may be the same or different from each other and each represents a hydrogen atom or a substituent, X represents an oxygen atom, a sulfur atom or N—R Y1 , R Y1 represents a hydrogen atom or a substituent, L represents a linking group comprising a conjugated bond, R X and R Y may be the same or different from each other and each represents a hydrogen atom or a substituent, with at least one of them being an electron-withdrawing group,

wherein the organic membrane comprises at least one compound selected from the compounds represented by the general formula (E 12):

wherein, in the general formula (E 12) X E represents O, S, N—R a or C—R a , R a represents a hydrogen atom or a substituent, Z b represents atoms necessary for forming a pyrimidine ring, a pyridazine ring, a pyrrole ring, a furan ring, a thiophene ring, a selenophene ring, a tellurophene ring, an imidazole ring, a thiazole ring, a selenazole ring, a tellurazole ring, a thiadiazole ring, an oxadiazole ring and a pyrazole ring, m 6 represents an integer of 2 or more, and L 6 represents a linking group.

2. The light-emitting element of claim 1 , wherein a difference in ionization potential between the organic membrane and the host material in the light-emitting layer is 0.01 eV to 2 eV.

3. The light-emitting element of claim 1 , wherein the compound represented by the general formula (I) is a compound represented by the following general formula (II):

wherein R 1 , R 2 , R 3 , R 4 and R 5 may be the same or different from each other and each represents a hydrogen atom or a substituent, X represents an oxygen atom, a sulfur atom or N—R Y1 , R Y1 represents a hydrogen atom or a substituent, Z 2 represents atoms necessary for forming 5- or 6-membered ring, L 21 and L 22 may be the same or different from each other and each represents a methine group, a substituted methine group or a nitrogen atom, n represents an integer of 0 to 3, and Ar represents an arylene group or a divalent aromatic hetero ring group.

4. The light-emitting element of claim 3 , wherein the compound represented by the general formula (II) is a compound represented by the following general formula (III):

wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 31 , R 32 , R 33 and R 34 may be the same or different from each other and each represents a hydrogen atom or a substituent, Z 3 represents atoms necessary for forming 5- or 6-membered ring, L 21 and L 22 may be the same or different from each other and each represents a methine group, a substituted methine group or a nitrogen atom, and n represents an integer of 0 to 3.

5. The light-emitting element of claim 4 , wherein the compound represented by the general formula (III) is a compound represented by the following general formula (IV):

wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 31 , R 32 , R 33 , R 34 , R 41 , R 42 , R 43 and R 44 may be the same or different from each other and each represents a hydrogen atom or a substituent, and R A1 and R A2 may be the same or different from each other and each represents a hydrogen atom or a substituent and, when possible, R A1 and R A2 may be connected to each other and further to other substituent to form a ring.

6. The light-emitting element of claim 1 , wherein the host material is an aluminum quinoline derivative.