Patent ID: 8802245

Claim:
A polymer composition comprising 1 to 99 wt % of the following copolymer (A) and 99 to 1 wt % of the following copolymer (B): Copolymer (A): a copolymer showing fluorescence in the solid state and having a polystyrene-reduced number average molecular weight of 10 3 to 10 8 , and containing a repeating unit (a) and a repeating unit (b), and said copolymer has a relation of 100>X aA >5, provided that X aA (%) is a percentage of the mol number of the repeating unit (a) based on the sum of the mol numbers of the repeating units (a) and (b), and Copolymer (B): a copolymer showing fluorescence in the solid state and having a polystyrene-reduced number average molecular weight of 10 3 to 10 8 , and containing (a) a repeating unit and (b) a repeating unit, and said copolymer satisfies a relation of X aB ≦X aA −5, provided that X aB (%) is a percentage of the mol number of the repeating unit (a) based on the sum of the mol numbers of the repeating units (a) and (b); wherein the repeating unit (b) is a repeating unit represented by the following formula (2): wherein, X represents —CR 3 R 4 —, —O—, —S—, —Se— or —SiR 5 R 6 —, p and q represent each independently an integer of 0 to 3, R 1 and R 2 represent each independently an alkyl group, aryl group or mono-valent heterocyclic group; two or more of R 1 and R 2 may be connected to form a cyclic structure; R 3 , R 4 , R 5 and R 6 represent each independently an alkyl group, alkoxy group, alkylthio group, alkylsilyl group, alkylamino group, aryl group, aryloxy group, arylsilyl group, arylamino group, arylalkyl group, arylalkoxy group, arylalkylsilyl group, arylalkylamino group, mono-valent heterocyclic group or cyano group; when there are a plurality of R 1 and R 2 , respectively, they may be the same or different; and further, when R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are groups having an alkyl, the alkyl may be interrupted by a group containing a hetero atom, and wherein when X represents —CR 3 R 4 —, two or more of R 1 and R 2 are connected to form a cyclic structure.