Patent ID: 8679649

Claim:
A material for an organic electroluminescence device, comprising a compound represented by formula (3a) and a compound represented by formula (3b), wherein the compound represented by formula (3a) has a molecular weight smaller than that of the compound represented by formula (3b), and the material has a content ratio of the compound represented by formula (3a) to the compound represented by formula (3b) of from 0.1 to 5,000 ppm: wherein each of R 1a to R 1i in formula (3a) is the same as the corresponding R 1a to R 1i in formula (3b), and each R 1a to R 1i in formula (3a) and formula (3b) independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 20, a cycloalkyl having a carbon number of 3 to 8, an aryl group having a carbon number of 6 to 18, an cyano group, or a fluoro group; n is 1 or 2; and L a and L b form one of the following bidentate ligands: wherein each of Rx, Ry and Rz independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 20, a cycloalkyl group having a carbon number of 3 to 8, or an aryl group having a carbon number of 6 to 18; and M 1 corresponds to Ir in formula (3a).