Host material for delayed fluorescent materials, organic light-emitting device and compound

An organic light-emitting device comprising a layer that contains a delayed fluorescent material and a host material represented by the following general formula (1):

• (Tr)n-Z General Formula (1)
• wherein Tr represents a substituted or unsubstituted triphenylenyl group, and plural Tr's existing in the general formula (1) may be the same as or different from each other;
• Z represents a carbonyl group or a substituted or unsubstituted, n-valent aromatic hydrocarbon group;
• n represents an integer of 2 to 6, but when Z is a carbonyl group, then n is 2.

A compound represented by the following general formula (4):

• (Tr3)n1-Z General Formula (4)
• wherein Tr3 represents a substituted or unsubstituted triphenylenyl group, and plural Tr3's existing in the general formula (4) may be the same as or different from each other;
• Z1 represents a substituted or unsubstituted n-valent aromatic hydrocarbon group;
• n1 represents an integer of 2 to 6;
• at least one of Tr3 and Z1 is substituted with a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group;
• when Tr3 is unsubstituted, then Z1 is a benzene ring residue substituted with a phenyl group or a methyl group and bonds to Tr3 at the 1-position and the 3-position, or is a biphenyl residue substituted with a phenyl group.