Patent ID: 6403237
Filing Date: 2002-06-11
Classification: C08G,C09K,H01L,H05B,Y10S

Abstract:
A polymeric fluorescent substance showing visible fluorescence in solid state and having a polystyrene-reduced number-average molecular weight of 103 to 107, wherein the polymeric fluorescent substance comprises one or more repeating units represented by the following formula (1) and one or more repeating units represented by the following formula (2), the sum of the repeating units represented by the formula (1) is from 0.5% by mole to 95% by mole based on the total amount of repeating units, the sum of the repeating units represented by the formula (1) and the repeating units represented by the formula (2) is from 50% by mole to 100% by mole based on the total amount of repeating units, and the molar ratio of the sum of the repeating units represented by the formula (1) to the sum of the repeating units represented by the formula (2) is from 20:1 to 1:199: whereinAr1 represents a condensed polycyclic aromatic group which may be substituted with a substituent selected from the group consisting of a cyano group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkylsilyl group having 3 to 60 carbon atoms, an alkylamino group having 1 to 40 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an arylalkenyl group having 8 to 20 carbon atoms, an arylalkynyl group having 8 to 20 carbon atoms, an aralkyl group having 7 to 14 carbon atoms and a heterocyclic compound group having 4 to 14 carbon atoms, and which satisfies the following conditions (a) to (c): (a) bond {circle around (1)} and bond {circle around (2)} are attached to carbon atoms on Ar1 that are not adjacent each other and the number of carbon atoms forming conjugated bonds, excepting any carbon atoms of said substituent, is from 16 to 30; (b) a condensed polycyclic aromatic compound, obtained by replacing all substituents on Ar1 by hydrogen atoms and by substituting hydrogen atoms at the two bonding sites {circle around (1)} and {circle around (2)}, has a plane of symmetry, a twofold rotational axis or a threefold rotational axis, said plane of symmetry or rotational axis is perpendicular to the plane including the condensed polycyclic aromatic compound and contains only 6-membered-ring structures; (c) the two carbon atoms to which bond {circle around (1)} and bond {circle around (2)} are attached are selected from the group consisting of carbon atoms at the corresponding location to those of said condensed polycyclic aromatic compound to which a hydrogen atom is bonded; and: the two carbon atoms on Ar1 to which bond {circle around (1)} and bond {circle around (2)} are attached are selected from the group consisting of carbon atoms having the largest and second-largest sum of squares of atomic orbital coefficients in the highest occupied molecular orbitals, wherein the sum of squares of atomic orbital coefficients in the highest occupied molecular orbitals is calculated by the semi-empirical molecular orbital AM1 method; and R1 and R2 each independently represents a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a heterocyclic compound having 4 to 20 carbon atoms and a cyano group; â€”Ar2â€”CR3&boxH;CR4â€”â€ƒâ€ƒ(2) â€ƒwherein Ar2 represents an arylene group or a heterocyclic compound in which the number of carbon atoms forming conjugated bond is from 4 to 20, and is not the same as the Ar1 group in said formula (1), and R3 and R4 each independently represents a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a heterocyclic compound having 4 to 20 carbon atoms and a cyano group.