Phosphors, process for production thereof, phosphorescent compositions and articles made by using the same

2] The phosphorescent agent according to claim 1, wherein at least one of the structural units represented by the general formula (1) contained in the molecule is such that L indicating the organic ligand in the general formula (1) has an organic ligand represented by the following general formula (2):

• 6
• wherein each of R3 and R4 is, independently, a hydrogen atom, halogen atom, alkyl group or aryl group, and each of n and o is, independently, an integer of 1 to 5.

3] The phosphorescent agent according to claim 1 or 2, wherein M indicating the metal atom in the general formula (1) is a metal atom selected from the group consisting of Pd, Pt, Rh, Ir, Ru, Os and Re.

4] The phosphorescent agent according to any one of claims 1 to 3, which comprises the structural unit represented by the general formula (1), a structural unit derived from N-vinyl-carbazole and a structural unit derived from vinyl-substituted 1-oxa-3,4-diazole.

5] A process for producing the phosphorescent agent according to any one of claims 1 to 4, which comprises reacting a picolinic acid structure-containing polymer with a metal complex.

6] The production process of the phosphorescent agent according to claim 5, wherein the metal complex is a metal complex having a metal atom selected from Pd, Pt, Rh, Ir, Ru, Os and Re as a central metal.

7] A luminescent composition comprising the phosphorescent agent according to any one of claims 1 to 4 and an organic solvent.

8] The luminescent composition according to claim 7, which is suitable for use in an organic electroluminescence device.

9] An organic electroluminescence device comprising at least an anode layer, a luminescent layer obtained from a material containing the phosphorescent agent according to any one of claims 1 to 4 and a cathode layer.

10] The organic electroluminescence device according to claim 9, which is obtained by laminating the anode layer, a hole-transporting layer, a copper phthalocyanine layer and the luminescent layer in this order.

11] The organic electroluminescence device according to claim 9 or 10, which has a luminescent layer composed of the luminescent composition according to claim 7 or 8.

12] An organic electroluminescence device obtained through a step of forming a luminescent layer by applying the luminescent composition according to claim 7 or 8 to a surface of a substrate, on which the luminescent layer should be formed, and subjecting the applied composition to a heating treatment.