A polymer having a repeating unit structure represented by the following general formula (1), wherein in general formula (1), Ph is a phenyl group; X is an oxygen atom, a sulfur atom, a selenium atom or a tellurium atom; and R1 and R1 each independently contains at least one selected from the group consisting of a chained saturated hydrocarbon group, a chained unsaturated hydrocarbon group, a cyclic saturated hydrocarbon group, a cyclic unsaturated hydrocarbon group, a phenyl group, a hydrogen atom, a hydroxyl group, a cyano group, an amino group, a nitro group and a nitroso group. The chained saturated hydrocarbon group, the chained unsaturated hydrocarbon group, the cyclic saturated hydrocarbon group and the cyclic unsaturated hydrocarbon group each contain at least one selected from the group consisting of a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom and a silicon atom: