Development of White-light-emitting Organic Electroluminescent Device

利用染料分散聚合物发光层和多层器件结构研制了白光有机电致发光器件。在聚合物发射层的情况下，为了实现单一聚合物发射层的双极性，空穴传输聚(N-乙烯基咔唑)(PVK)被电子传输添加剂如2-(4-联苯基)-5-(4-叔丁基苯基)-1，3，4-恶二唑分子分散。此外，几种具有不同发射颜色的荧光染料分散在AA发射中心。通过调节荧光染料的浓度，获得了最大亮度为4100cd/m^2的白光，这是有机电致发光器件中观察到的最亮的白光。在多层结构的情况下，使用具有不同载流子传输特性的三个发射体层来产生白光，每个发射体层发射蓝、绿或红光。成功地获得了大于2000cd/m^2的明亮白光。我们还合成了含有三苯胺基团和蓝色荧光染料的空穴传输聚合物，用于电致发光。

White light-emitting organic electroluminescent devices were developed by using dye-dispered polymer emitter layrs and by using a multilayr device structure. In case of the polymer emitter layr, in order to achieve bipolarity in the single polymer emitter layr, hole-transporting poly (N-vinylcarbazole) (PVK) was molecularly dispersed with electron-transporting additives such as 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole. In addition, several fluorescent dyes, having different emission colors, were dispersed aa emitting centers. By adjusting the concentration of the fluorescent dyes, white light with a maximum luminance of 4100 cd/m^2 was obtained, which is the brightest white light ever observed for organic electroluminescent devices. In case of the multilayr trpe, three emitter layrs with different carrier transport properties, each emitting blue, green or red light, are used to generate white light. Bright white light, over 2000 cd/m^2, was successfully obtained. We have also synthesized hole-transporting polymers containing triphenylamine moieties and blue-emitting fluorescent dyes for EL application.