Blue, green, and red emission

Meerholz and coworkers incorporated the HTM (triphenyldiamine derivative) into the backbone of SPF to elevate the device efficiency through promoting hole injection/transport properties [24]. The cross-linkable oxetane-functionalized SPF derivatives 10-12 were also synthesized to realize full color display via spin-coating processes. The resulting EL devices (ITO/PEDOT PSS/10, 11, or 12/Ca/Ag) showed maximum efficiencies of 2.9, 7.0, and 1.0 cd A-1 for blue, green, and red emissions, respectively. 

Fig. 11.3 Chemical structures of commonly used Ir-dyes with blue, green and red emission bis(2-(4,6-difluorophenyl)pyridyl-N,C2 )iridiumpicolinate (FIrpic), /nc-tris(2-phenylpyridine) iridium Ir(ppy)3 and bis(2-(2 -benzothienyl)-pyridinato-N,C3)iridium(acetylacetonate) btp2l r(acac).

Tokito et al. [85] studied a series of copolymers based on a nonconjugated backbone, having carbazole and emissive Ir-complexes in the side chain. Even though the chemical structures of these polymers are quite simple, rather high quantum efficiencies (3 %, 9 % and 5 % for blue, green and red emission, respectively) were reported in a single-layer device structure. 

Liu, J., Zhou, Q., Cheng, Y., Ceng, Y, Wang, L., Ma, D., Jing, X., Wang, E, 2005. The first single polymer with simultaneous blue, green, and red emission for white electroluminescence. Adv. Mater. 17, 2974-2978. 

Pig. 6.4 Polarized electroluminescence spectra of devices containing glassy-nematic films of fluorene-based oligomers having blue, green and red emission. EL and ELj represent the emitted intensity paraUel and perpendicular to the alignment direction (Copyright (2(X)3) American Chemical Society)... 

This phosphor has many emission lines in the blue, green, and red areas of the electromagnetic spectrum screens made from it have a whitish appearance... 

J.-F. Morin and M. Leclerc, 2,7-Carbazole-based conjugated polymers for blue, green, and red light emission, Macromolecules, 35 8413-8417, 2002. 

The simplest method yet most complex structure for white OLEDs consists of three primary emission colors blue, green, and red. Kido et al. reported using three emitter layers with different carrier transport properties to produce a white emission [273], The multilayer structure of such an OLED is ITO/TPD/p-EtTAZ/Alq3/Alq3 Nile Red/Alq3/Mg Ag, in which a blue emission from the TPD layer, a green emission from the Alq3 layer, and a red... 

In other white light devices, blue, green and red emitters are combined. Kido et al. [169, 170] designed multilayer systems using 6 (TPD) for blue, metal-chelate complexes for green and red emission, respectively. Similar devices have been developed by other groups, using Forster transfer or exciton confinement for the creation of the three primary colors [171, 172]. Exciplex emission was... 

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