The core thicknesses of macroscopic, vertical foam films have been measured by FT-IR technique for the equilibrium films formed from palmitoyllysophosphatidylcholine (lysoPC) solutions in varying concentrations of NaCl and CaCl2. The addition of NaCl exhibits no effect on the core thicknesses of equilibrium films; Newton black films (NBF) with constant core thickness of 2.5 nm are observed in the range of the measured concentrations up to 1M NaCl. Whereas, in CaCl2 the core thicknesses in equilibrium state strongly depend on CaCl2 concentrations. Consequently, the equilibrium films are NBF at below about 1.1 X KH M, silver films (SF) at about 1-4 X 1(H M, common black films (CBF) at about 5 X 1CH to 0.2 M and again NBF at higher concentrations than about 0.2 M. These transitions of film thickness are thought to be due to specific adsorption of Ca2+ on the zwitterionic head group. So, using the measured thickness of the film core and the Lifshitz theory applied for a triple-layer model, van der Waals dispersion forces ( ) were calculated and from the the effective Hamaker constants, A (h, 298 K), for a foam water film were simultaneously calculated. The values obtained vary from 2 X KH°J to 4.5 X Kb20 J in the range 5nm -30nm of film thicknesses. Next, for the equilibrium SF and CBF, surface potential^), surface charge density (a), and the binding constant (K) of Ca2+ to the equilibrium foam films were evaluated using the charge-regulation model taking account of the DLVO theory of colloid stability. At the thickness-transition concentration of 1.1 X 1(H M CaCl2 0 and are 11 mV and 1.3 X 1(H C nr* 12 345, respectively. Further, K is almost independent of the CaCl2 concentration in the range 3 X 1(H M to 0.1 M, i.e., the binding constant of Ca2+ to the lysoPC foam film is given as 15 ± 5 M-1 assuming a 2:1 stoichiometry for the PC/Ca2+.

The surface energy controlled ink-jet printing with ultraviolet (UV) irradiation on a novel polyimide film was developed for high-resolution electrode patterning. Minimum linewidth of electrode was 15 µm and minimum space between two electrodes was 2 µm respectively. 160 ppi and 200 ppi all-printed organic thin film transistor (OTFT) backplanes were fabricated by the surface energy controlled ink-jet printing for electrodes, conventional ink-jet printing for organic semiconductor (OSC) and several printing methods on plastic substrate. We have also fabricated a 300 ppi all-printed OTFT array on plastic substrate. Flexible electrophoretic displays (EPDs) driven by 200 ppi all-printed OTFT backplanes were also successfully demonstrated.

An organic light-emitting diode containing titanyl phthalocyanine (TiOPc) and tris-(8-hydroxy quinoline) aluminum (Alq 3 ) layers has been fabricated. The device exhibits green emission from the Alq 3 emissive layer under ambient conditions. Below the turn-on voltage, the green emission is instantaneously switched on by laser irradiation at 650 nm, indicating that the device can be used as a red-to-green light converter. Above the turn-on voltage, the green emission is greatly enhanced by laser irradiation, while the current-voltage characteristics are significantly modified. Amplification factors of the emission intensity as well as the current density upon laser irradiation are found to greatly depend on the TiOPc layer thickness. The TiOPc layer acts as a hole generation layer rather than as a buffer layer.

FT-IR spectra of black lipid films formed by dimyristoylphosphatidylcholine (DMPC) in air were recorded at various temperatures for the first time. Black lipid films drawn from a DMPC aqueous dispersion and a DMPC + 0.1 MCaCl2 aqueous dispersion showed the gel to liquid crystal phase transition at about 24 and 27 °C, respectively.

Polarized Fourier transform infrared spectra of black lipid films in air withdrawn from aqueous dispersions of dimyristoylphosphatidylcholine (DMPC) have been recorded at various electrolyte concentrations. The spectra revealed that monovalent cations gave little effect, whereas polyvalent cations except Mg2+ gave remarkable effects on vibrational wavenumbers of both the acyl chain and phosphate ester group of DMPC in black lipid films. In the case of Mg2+, the effect was discerned only for the phosphate ester group. By use of thin film optics, molecular orientation of DMPC in the black lipid film in air was quantitatively evaluated as a function of electrolyte concentration. In the case of monovalent and Mg2+ cations, the orientation angle of the acyl chain axes from the surface normal was little affected by the electrolyte addition. On the other hand, the other polyvalent cations caused decrease of the average orientation angle from ca. 40° to 30°. The affinity of the cations for the DMPC lipid films in air are in the order of Zn2+ > La3+ ∼ Ca2+ ∼ Pb2+ > Mg2+ > Na+ ∼ Li+.