Patent ID: 9257680
Filing Date: 2016-02-09
CPC Classification: C09K,H01L

Claim Text:
1. A method of manufacturing an organic electroluminescent element comprising a substrate, a hole transport layer containing a polymer, and a light emission layer containing a phosphorescence dopant, the method comprising the steps of: purifying a monomer with silica gel chromatography one or two times, followed by recrystallization two or three times to make a purified monomer having an impurity content of 1000 ppm or less; synthesizing the polymer from at least the purified monomer having the impurity content of 1000 ppm or less via a halogen coupling reaction; recovering the polymer; forming the hole transport layer containing the polymer on the substrate by a wet coating process followed by a heating process; and forming the light emission layer containing the phosphorescence dopant on the hole transport layer, wherein the polymer comprises a partial structure represented by the following formula wherein each of Ar1 and Ar2 independently represents an arylene group or a heteroarylene group, and Ar3 represents an aromatic hydrocarbon group or an aromatic heterocyclic group.