Polymeric fluorescent substance and polymer light-emitting device using the same

A polymeric fluorescent substance showing fluorescence in the solid state and having a polystyrene reduced number-average molecular weight of 103 to 108, wherein the substance is a random copolymer and contains one or more repeating units of formula (1) and one or more repeating units of formula (2), and the total amount of repeating units of formula (1) is 10 mol% or more and 90 mol% or less based on the total amount of repeating units of formulae (1) and (2):

• wherein, R1, R2, R3 and R4 represent each independently a hydrogen atom or a substituent, and at least one of R1, R2, R3 and R4 is a group selected from the group consisting of alkoxy groups, aryl groups substituted with an alkoxy group, aryloxy groups and arylalkoxy groups,
• —Ar1— (2)
• wherein, Ar1 represents a different group from that of formula (1) and is a group selected from the group consisting of repeating units of formula (8):
• wherein, R13 and R16 represent each independently a group selected from the group consisting of alkyl groups having 1 to 20 carbon atoms, alkoxy groups having 1 to 20 carbon atoms, alkylthio groups having 1 to 20 carbon atoms, alkylsilyl groups having 1 to 60 carbon atoms, alkylamino groups having 1 to 40 carbon atoms, aryl groups having 6 to 60 carbon atoms, aryloxy groups having 6 to 60 carbon atoms, arylsilyl groups having 6 to 60 carbon atoms, arylamino groups having 6 to 60 carbon atoms, arylalkyl groups having 7 to 60 carbon atoms, arylalkoxy groups having 7 to 60 carbon atoms, arylalkylsilyl groups having 7 to 60 carbon atoms, arylalkylamino groups having 7 to 60 carbon atoms, arylalkenyl groups having 8 to 60 carbon atoms, arylalkynyl groups having 8 to 60 carbon atoms, monovalent heterocyclic compound groups having 4 to 60 carbon atoms and a cyano group;
• c and d represent each independently an integer of 0 to 4;
• when c is 2 or more, a plurality of R13s may be the same or different;
• when d is 2 or more, a plurality of R16s may be the same or different;
• wherein one or two of substituents on a benzene ring are groups selected from the group consisting of alkoxy groups, aryl groups substituted with an alkoxy group, aryloxy groups and arylalkoxy groups, R14 and R15 represent each independently a group selected from the group consisting of a hydrogen atom, alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 60 carbon atoms, arylalkyl groups having 7 to 60 carbon atoms, monovalent heterocyclic compound groups having 4 to 60 carbon atoms and a cyano group;
• R13 to R16 may be connected to form a ring;
• and when R13 to R16 are a group containing an alkyl chain, one or more of a methyl group, a methylene group and a methine group constituting the alkyl chain may be substituted with a group containing a hetero atom;
• and formula (12):
• wherein, Ar5 represents an arylene group or a divalent heterocyclic compound group;
• R24 and R29 represent each independently a group selected from the group consisting of alkyl groups having 1 to 20 carbon atoms, alkoxy groups having 1 to 20 carbon atoms, alkylthio groups having 1 to 20 carbon atoms, alkylsilyl groups having 1 to 60 carbon atoms, alkylamino groups having 1 to 40 carbon atoms, aryl groups having 6 to 60 carbon atoms, aryloxy groups having 6 to 60 carbon atoms, arylsilyl groups having 6 to 60 carbon atoms, arylamino groups having 6 to 60 carbon atoms, arylalkyl groups having 7 to 60 carbon atoms, arylalkoxy groups having 7 to 60 carbon atoms, arylalkylsilyl groups having 7 to 60 carbon atoms, arylalkyamino groups having 7 to 60 carbon atoms, arylalkenyl groups having 8 to 60 carbon atoms, arylalkynyl groups having 8 to 60 carbon atoms, monovalent heterocyclic compound groups having 4 to 60 carbon atoms and a cyano group;
• q and r represent each independently an integer of 0 to 4;
• when q is 2 or more, a plurality of R24s may be the same or different;
• when r is 2 or more, a plurality of R29s may be the same or different;
• R25 to R28 represent each independently a group selected from the group consisting of a hydrogen atom, alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 60 carbon atoms, arylalkyl groups having 7 to 60 carbon atoms, monovalent heterocyclic compound groups having 4 to 60 carbon atoms and a cyano group;
• R24 to R29 may be connected to form a ring;
• and when R24 to R29 are a group containing an alkyl chain, one or more of a methyl groups, a methylene group and a methine group constituting the alkyl chain may be substituted with a group containing a hetero atom.