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New blue fluorescent spirobenzoanthracene-type dopant materials, 3,9-di(di(p-tolyl))aminospiro[benzo[de]anthracene-7,9′-fluorene] (DTSBAF) and 3,9-di(di(4-biphenyl))aminospiro[benzo[de]anthracene-7,9′-fluorene] (DBSBAF), were designed and successfully prepared by an amination reaction of 3-bromo-9-chlorospiro[benzo[de] anthracene-7,9′-fluorene] with di(p-tolyl)amine and di(4-biphenyl)amine, respectively. The EL characteristics of 1,10-dinaphthylspiro[benzo[ij]tetraphene-7,9′-fluorene] (DNSBTF) as the blue host material doped with the above blue dopant materials was evaluated. The electroluminescence spectra of indium tin oxide (150 nm)/N,N′-diphenyl-N,N′-bis[4-(phenyl-m-tolyl-amino)phenyl]-biphenyl-4,4′-diamine (DNTPD, 60 nm)/N,N,N′,N′-tetra(1-biphenyl)-biphenyl-4,4′-diamine (TBB, 30 nm)/SBTF hosts: SBAF dopant (20 nm, 5%)/9,10-di(naphthalene-2-yl)anthracen-2-yl-(4,1-phenylene)(1-phenyl-1H-benzo[d]imidazole) (LG201, 20 nm)/LiF (1 nm)/Al (200 nm) with DNSBTF as a host material show a blue emission band with a full width at half maximum of 50 nm and λmax = 472 nm. The device obtained from DNSBTF doped with DTSBAF showed a good color purity (0.141, 0.254), high luminance efficiency (10.12 cd A−1 at 5 V) and high external quantum efficiency (6.02%).

Chiral dopants were synthesized from bio-based epimeric isohexides (glucose-derived isosorbide and mannose-derived isomannide) and their phase transition behaviors and abilities for developing cholesteric liquid crystal (CLC) films were examined with a consideration of the core structure. In spite of lower reactivity of the endo hydroxy group of isomannide caused by the steric hindrance and intermolecular hydrogen bonding, final synthetic yields of chiral dopants bearing an isomannide core (64.5% for IH-2 and 65.0% for IH-4) did not show conspicuous difference compared with chiral dopants bearing isosorbide (68.4% for IH-1 and 74.0% for IH-3). On the other hand, in phase transition behaviors, chiral dopants bearing an isomannide core showed lower crystalline and melting temperatures than IH-1, IH-3 despite of the same substituents. The helical twisting power (HTP) of chiral dopants bearing isosorbide (IH-1 and IH-3) was higher than that of chiral dopants bearing isomannide (IH-2 and IH-4). The calculated HTPs of IH-1 and IH-3 were 26.6 and 42.1 μm−1, respectively. In the case of IH-3, the helical pitch length of CLC could be adjusted to reflect visible light by controlling its amount and showed best performance in the range 5.0 to 7.0 mol%. In contrast to IH-1 and IH-3, it was found that IH-2 and IH-4 could not induce CLC films that reflect visible light.