| abstract |
A polymeric fluorescent substance which is soluble in solvents, has a number-average molecular weight of 10³ to 10⁷ and contains, as main constituents, three different repeating units A, B and C selected from various repeating units represented by the following formula (1), wherein the ratios of the respective repeating units in the polymeric substance are such that when the repeating unit constituting the polymer having the longest optical absorption edge wavelength is expressed by A, the repeating unit constituting the polymer having the next longest optical absorption edge wavelength is expressed by B and the repeating unit constituting the polymer having the shortest optical absorption edge wavelength is expressed by C, A is contained in an amount of 2-60 mol%, B in an amount of 5-60 mol% and C in an amount of 20-50 mol% based on the total number of the three different repeating units: n n n n -Ar-CH=CH- (1) n n n nwherein Ar is a arylene group having 6 to 20 carbon atoms, a heterocyclic compound group having 4 to 20 carbon atoms or a divalent group represented by the following formula (2), and at least one of the repeating units A, B and C has at least one substituent selected from alkyl, alkoxy and alkylthio groups having 2 to 22 carbon atoms, aryl and aryloxy groups having 6 to 60 carbon atoms and heterocyclic compound groups having 4 to 60 carbon atoms: n n n n -Ar₁-X₁-R-X₂-Ar₂- (2) n n n nwherein Ar₁ and Ar₂ are each a arylene group having 6 to 20 carbon atoms or a heterocyclic compound group having 4 to 20 carbon atoms and may contain at least one substituent of at least one species of group selected from alkyl, alkoxyl and alkylthio groups having 2 to 22 carbon atoms, aryl and aryloxy groups having 6 to 60 carbon atoms and heterocyclic compound groups having 4 to 60 carbon atoms; R is a hydrocarbon or heterocyclic compound group having 1 to 22 carbon atoms; and X₁ and X₂ represent independently -O-, -S-, -COO- or -OCO-. |