. . "up.A1 is a linking group, and n.sup.A1 is an integer of 2 or more.##STR00002##In formula (B-1), Z.sup.B1 represents an atomic group necessary for forming an aromatic hydrocarbon ring or an aromatic heterocycle, L.sup.B1 is a linking group, and n.sup.B1 is an integer of 2 or more.The compound represented by formula (A-1) is explained.In formula (A-1), L.sup.A1 is a linking group." . .