Three polytriphenylene derivatives with phenyl and alkyl groups as side chains have been tested as blue light emitters. The best performance in terms of turn-on voltage and luminance efficiencies was obtained for poly(2-heptyl-3-(4-octylphenyl)-1,4-diphenyl-6,11-triphenylenyl-1,4-benzene) (1), which was additionally blended with an electron-transporting and a hole-injection material in the device, and had an onset of 4.6 V and reached 0.73 cd · A(-1) .