| abstract |
A copolymer comprising a repeating unit of the following formula (1) and a repeating unit of the following formula (2): n n(wherein, a ring A and ring B represent each independently an aromatic ring optionally having a substituent. X is —O—, —S—, —S(═O)—, —S(═O) 2 —, —Si(R 1 ) 2 —Si(R 1 ) 2 —, —Si(R 1 ) 2 —, —B(R 1 )—, —P(R 1 )—, —P(═O)(R 1 )—, —O—C(R 1 ) 2 — or —N═C(R 1 )—, and R 1 represents a substituent. When there are two or more R 1 s in the same formula, they may be the same or different.)n n n(wherein, Y is —O—, —S— or —C(═O)—. Ar 1 represents an aryl group optionally having a substituent or a monovalent heterocyclic group optionally having a substituent, and there is no substituent connected to atoms of the ring of Ar 1 , the atoms being adjacent an atom of Ar 1 connected to a nitrogen atom in the formula. R 2 represents a substituent, and n represents an integer of from 0 to 3. When there are two or more R 2 s in the formula, they may be the same or different.). |