POLYMERIC PHOSPHOR AND POLYMERIC LIGHT EMITTING DIODE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an LED(light emitting diode) capable of being drived under a low voltage at high efficiency by using a polymeric phosphor having stronger fluorescence than that of conventional. SOLUTION: This polymeric fluorescent substance having fluorescence in a solid state and having 103-108 number-average molecular weight expressed in terms of polystyrene comprise one or more kinds of each recurring units represented by formula (1) (n is 0 or 1) and formula (2) (l is 0 or 1) which satisfies the following (a) to (c). (a) The total of recurring units represented by formula (1) and formula (2) is >=50 mol% based on all recurring units. (b) The recurring unit represented by formula (2) is in an amount of 0.1-9 mol% based on the total of recurring units represented by formula (1) and formula (2). (c) Absorption edge wavelengthλ1 (nm) of the polymer composed of only the recurring unit represented by formula (1) and absorption edge wavelengthλ2 (nm) of he polymer composed of only the recurring unit represented by formula (2) have a relationship as follows: (1239/λ1)>=[(1239/λ2)+0.05].