Organic EL devices

Adachi et al. showed that the ionization potential (IP) of HTLs was found to be the dominant factor for obtaining high durability in organic EL devices [70]. The formation of the small energy barrier at the interface of a HTL and anode was required for high durability. However, their results showed that there are no straightforward relationships between melting point, Ts of the HTMs, and durability of the EL devices. 

Y. Sato, S. Ichinosawa, T. Ogata, M. Fugono, and Y. Murata, Blue-emitting organic EL devices with a hole blocking layer, Synth. Met., 111-112 25-29 (2000). 

R Murayama, S Kawami, T Wakimoto, H Sato, H Nakada, T Namiki, K Imai, and M. Nomura, Organic EL devices doped with a quinacridone derivative showing higher brightness and luminescent efficiency, Jpn. Soc. Appl. Phys., Extended Abstracts (54th Autumn Meeting, 1993),3 1127, 1993. 

Poly[(p-butoxyphenyl)phenylsilane] (PBPPS) has been employed as an emissive layer of an organic EL device.95 PBPPS was spin coated onto an uniaxially oriented poly(diethylsilane) (PDES) ultrathin film. Polarized NUV-EL was observed and the polarization direction was found to be identical with the drawing direction of the friction-transfer process for the PDES film, indicating that PBPPS in the emissive layer was aligned parallel to the uniaxial orientation of PDES. 

FIGURE 19. A schematic drawing of an organic EL device using 26p, Alq and TPD as electrontransporting, emissive and hole-transporting materials, respectively. Reproduced by permission of the Royal Society of Chemistry from Reference 6b... 

Figure 135 Molecular structures of lanthanide complexes of europium (Eu), tris (thenoyltrifluoroacetonato) Eu3+ (a), tris(thenoyltri-fluoroacetonatoXmonophenanthroline) Eu3+ (b), and terbium (Tb), tris(acetylacetonato) Tb3+ (c) employed as narrow-band emitters in organic EL devices (see Ref. 19, 425, 534-536 and 539).

Fig. 7.2 Side view of the organic EL device consisting of double hole-transport layers.

Matsumoto, T., Nakada, T., Endo, J. et al. 2003. Multi-photon organic EL device having charge generation layer. SID Inti. Symp. Dig. Tech. Papers 34 979. 

S. Shirai and J. Kido. Syntheses of vinyl polymers containing phenylan-thracene pendants and their application for organic EL device. Chem. Lett., 31(3) 386-387, March 2002. 

Lin, R, et al. 2005. Rhotovoltaic character of organic EL devices MEH-PPV/Alqs. Guangpuxue Yu Guangpu Penxi 25 23 Chem Abstr 143 88243. 

Higuchi, K. Matsuo, Y. Formation of bunks using ink-jet printer and its application in manufacture of color filters, LCD panels, organic EL devices, and display panels. Jpn. Kokai Tokkyo Koho JP 2006171365, 2006 Chem. Abstr. 2006,145,73564. 

Fig. 13 (a) Schematic energy level diagram used for a two-layer organic EL device... 

The highest performance in blue organic EL devices was claimed by Hosokawa et al. [208] with a multiheterostructure device in which the active layer was a 1,4-bis(2,2-diphenylvinyl)biphenyl (DPVBi) doped with an amine. This group obtained a half-life (time in which luminance has decreased to 50% of its initial value) of more than 5000 h for devices driven initially at 100 cd/ m . The efficiency of this type of device is 5 Im/W, corresponding to an EL quantum efficiency of about 5%. These are the highest values obtained so far. 

Photo active iridium complexes are of potential in the organic EL device, which was also studied [83-86]. The introduction of the cationic luminescent iridium(III) complexes into negatively charged P(Glu) as a polymeric scaffold is allowed to perform the tuning of the emission properties in an aqueous media (Fig. 4.33) [87]. Increasing the ratio of the Glu unit of P(Glu) to the cationic cyclometalated... 

Matsukaze, N. Terao, Y. Manufacture of organic EL devices. Jpn. Kokai Tokkyo Koho JP 2001093664, 2001. 

TT-Conjugated linear polymers have attracted attention as materials in organic EL devices. The device using poly(p-phenylene vinylene) (PPV) sandwiched between indium oxide and aluminum electrodes emits green-yellow light at 14 V [167]. The quantum efficiency for the device was up to 0.05% photon per electron. EL devices based on poly[2-methoxy-5-(2 -ethyl)-... 

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