A shapely figure: A [32]octaphyrin(1.0.1.0.1.0.1.0) bis[palladium(II)] complex was selectively obtained through a metal-templated intermolecular homocoupling of a α,α'-dibromodipyrrin palladium(II) complex without formation the norcorrole. The weak antiaromatic character of the figure-eight [32]octaphyrin(1.0.1.0.1.0.1.0) system has been elucidated by spectroscopic measurements and DFT calculations.

Our deep-red phosphorescent organic light-emitting diode (OLED) demonstrated a long lifetime at 85C. This durability was derived not only from a stable exciplex host but also from a dopant with high thermal resistivity. The exciplex host made by a premix technique also worked as well as that made by codeposition. Author KeywordsOLED; Red phosphorescent OLED; high-temperature operational stability; exciplex; premix.

The effects of triplet-triplet annihilation (TTA) and molecular orientation were quantitatively investigated for a high-efficiency blue fluorescent organic light-emitting diode. Both the efficient TTA generation by improving carrier balance and the horizontal orientation of the transition dipole moment of the blue dopant realized ultrahigh external quantum efficiency (approximately 12%).

We developed a novel host-guest system that increases the lifetime of a deep-red phosphorescent OLED covering the wide color gamut of the BT.2020 standard. An OLED that employs this host-guest system has a ~5.4 times longer lifetime than an OLED that employs the conventional system. Author KeywordsOLED; Red phosphorescent OLED; BT.2020 color gamut; exciplex; long lifetime Background and ObjectivesOrganic light-emitting diodes (OLEDs) have been studied since Tang et al. reported a heterostructured OLED in 1987 [1]. Recently, medium-or small-sized panels with OLEDs have been used as next-generation displays in smartphones.Typical OLED displays are active-matrix OLED (AMOLED) displays. An AMOLED display requires a backplane suitable for OLED; thus, an appropriate field-effect transistor should be developed. We found a c-axis aligned crystalline In-Ga-Zn oxide (CAAC-IGZO) and a nanocrystal IGZO (nc-IGZO) [2,3,4], which have different crystal morphologies from a singlecrystal IGZO and an amorphous IGZO. We developed AMOLED displays whose backplanes contain such IGZOs [5,6]. OLED displays essentially have high contrasts, and thus provide the strong sense of immersion and realism [7]. To further improve the senses in these devices, a wide color gamut must be achieved.

We developed an electron-transport (ET) host material with a novel hetero fused ring which prolongs the lifetime of green phosphorescent organic light-emitting diodes (OLEDs). We also developed a premixed host containing the ET host and a holetransport host. The use of the premixed host can facilitate production of the OLEDs.