| 摘要 |
PROBLEM TO BE SOLVED: To provide a polymer LED drivable at low voltage and with high luminous efficiency by having a luminescent layer containing a polymeric phosphor specified in composition and molecular weight, between electrodes formed of a pair of positive electrode and negative electrode at least one of which is transparent or translucent, and specifying the metal of the negative electrode, and a compound and thickness of a buffer layer between the luminescent layer and the positive electrode. SOLUTION: This polymer light emission element comprises a polymeric phosphor containing one or more kinds of repeating units expressed by a formula: -AR1(CR1=CR2)n-, and so formed that the total of these repeating units is 50 mol% or more of all the repeating units and that number average molecular weight is 103-108. A negative electrode contains at least one kind of metal out of alkali metal, alkaline earth metal and lanthanoid. A buffer layer contains at least one kind of compound selected from an alkali metal fluoride and oxide, an alkali earth metal fluoride and oxide, and a lanthanoid fluoride and oxide, and its average thickness is 2 nm or less. |
