Liquid Crystal Displays (LCDs) have been developed because of their features: low power consumption and flat plate.
They have been widely employed in enterprises, homes and open air, all the better for such features. Potable notebook type of personal computers (PC) have been expanding in proportion to a development of large scale LCD panels. Especially, TFT-LCDs have been so remarkably improved in their image quality as flat panel display that they have already been employed for monitor display in PCs.
Chemical compounds of fluorinated derivatives are the most suitable and indispensable materials for TFT-LCD. It is Chisso Corporation that firstly developed the liquid crystal materials of fluorinated derivatives and that successfully established the manufacturing methods in the world.
In this paper, we are reporting a development process and introducing the properties of fluorinated materials. Furthermore, we are reporting the subjects that are needed for LCDs’ future and introducing the present developing situation.

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The Pd-based three-way catalyst (TWC) supported on Ni-aluminate (Ni_0.5Al₂O_3.5) is superior in catalytic conversions to the conventional Pd-based TWC supported on CeO₂ added γ-Al₂O₃. However, the activity of the former catalyst is degraded significantly by the aging process. To reveal the reason for this degradation, both of the catalysts after the aging were examined by means of X-ray diffraction analysis and transmission electron microscopic observation. It was found that part of Pd oxide in the former catalyst was reduced to metallic Pd by the aging process while the particle size of Pd oxide grew conspicuously compared with the case of the latter catalyst. This suggests that the Pd oxide in the former catalyst is not stable enough during the aging process, undergoing partial reduction as well as sintering. The addition of CeO₂ to the Ni-aluminate support was found to be effective for eliminating these in stabilities. An optimum loading of CeO₂ was shown to be 3.0–6.0 mol%. The resulting catalysts containing 3 mol% of CeO₂ after the aging were shown to be the highest in the light-off activity as well as in the TWC activity at 400 °C. XPS measurements revealed that the presence of CeO₂ could stabilize the oxidized state of palladium keeping from being to reduced to metallic Pd even when exposed to hydrogen at 400 °C for 15 min.

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The behavior of color degradation of polynuclear aromatic hydrocarbons in toluene by sunlight was investigated at ambient temperature, using UV-vis, FT-IR, GPC and mass spectroscopy. Color of the solution containing three to five fused-ring aromatic hydrocarbons turned from pale yellow to dark brown and the amount of sediment formed increased with increasing sunlight irradiation. Contrary, no color degradation was observed in the solution of two fused-ring aromatics under the same conditions of irradiation. Additional charge of olefinic hydrocarbons to the solution of polynuclear aromatics did not give any significant effects on the behavior of color degradation. The color bodies formed from pyrene-toluene solution during irradiation comprised mainly oxidized pyrene and toluene with carbonyl, carboxyl, and hydroxy groups. The products of oxidation seem to combine with each other via chemical bonding including hydrogen bonds to form sediment.

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Changes in the mechanical properties on the top and the bottom faces of float glass by weathering were compared, and factors governing these properties were investigated. The resistance to the formation of radial cracks was shown to improve by the weathering, and the level of its improving was significantly high for the top face compared with that for the bottom face. Secondary ion mass spectrometry (SIMS) depth profiles have shown that the hydrated layer, which originates from the ion exchange reaction between Na⁺ and H⁺, easily forms on the top face compared with the bottom face on weathering. The significantly improved resistance to the formation of radial cracks for the top face can be explained by the low hardness of the hydrated layer. Furthermore, it has been proved that the Sn²⁺ ion suppresses the ion exchange reaction between Na⁺ and H⁺ in the glass surface. Consequently, the thinner hydrated layer on the bottom face compared with that on the top face can be ascribed to the existence of polarizable Sn²⁺ ion, which penetrates into the bottom face of float glass during the float process. These results indicate the successful control of the ion exchange reaction important for controlling the mechanical properties of float glass.

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The influences to the global atmospheric environment by anthropogenic trace gases emitted by human activities are seriously concerned. Tokyo is one of the largest cities in the world, and includes all kind human activities: i.e., industries, automobiles, facilities, etc. Therefore, all kinds of anthropogenic emissions are expected in the Tokyo area. Radioisotope Center of the University of Tokyo is located at the center of Tokyo area, and air samples were continuously drawn from the top of the building into the laboratory, cryogenically preconcentrated, and analyzed with a GC-MS system. The atmospheric concentrations of 21 volatile organic compounds (VOCs; hydrocarbons and halocarbons including CFC substitutes) were measured every 3 hours for 100 days, and their variations were analyzed using correlation with meteorological conditions and human activities. Parameters used for the analysis are (1) atmospheric averaged concentration ratios of the weekdays (from Monday to Friday) to Sunday’s, (2) distribution patterns of concentration variations, (3) ratios of the weekday’s averaged concentrations observed at the center of Tokyo area to the background concentrations obtained from Hokkaido samples, (4) diurnal variations, (5) influence of wind direction, etc. As a result, it was shown that such parameters exactly reflected recent emission of each compound in the Tokyo area. Therefore, precise monitoring of atmospheric trace gases in urban areas will be useful for the understanding of the situation of their emissions by human activities (specially, industries and automobiles). Since the CFC substitutes such as hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are emitted largely in urban areas and their global concentrations increase slowly, the future changes of global atmospheric conditions will be anticipated from their trends in urban areas.

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A decomposition of phenolic endocrine disrupting chemicals (2,4-dichlorophenol, nonylphenol and bisphenol A) in aqueous solutions by potassium permanganate was tested. A solid phase micro extraction-gas chromatographic (SPME-GC) method was used for the analysis. Each compound (1 mg/L) in the mixed solution was completely decomposed by potassium permanganate (64 mg/L) within 60 min. The reaction efficiency was in the order of nonylphenol > bisphenol A > 2,4-dichlorophenol > phenol.

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The adsorption behavior of anionic surfactants [sodium α-alkylphenyl poly(oxyethylene)-ω-sulfate; R–C₆H₄–(OCH₂CH₂)_n–OSO₃Na, R = nonyl or octyl group, n = 9, 22 and 50] on smectite and their effect for rheological property of the smectite-water dispersion (2 wt% smectite) were investigated at 25 °C. The adsorbed amount of the sulfate anion was found to be increased with increasing the concentration of the sulfate anion and the number of oxyethylene unit (n value) in the sulfate anion, which was observed remarkable in alkaline solutions and not so in acid solutions. From the results, it was assumed that the sulfate anion is adsorbed on layer surface by the interaction with polyoxyethylene moiety in alkaline solutions and also on layer edge by the electrostatic interaction with sulfate group in acid solutions. In the measurement of rheological property, the apparent viscosity was decreased with increasing the adsorbed amount of the sulfate anion in alkaline solutions. In the case of addition of acid to the dispersion, the change in the apparent viscosity of the dispersion seems to be smaller than in the case of absence of the sulfate anion. Therefore, it was considered that the sulfate anion adsorbed on layer surface or layer edge depend on the dispersion pH prevents the association of smectite particles in the dispersion. Thus by the formation of the smectite sulfate anion composite, smectite became useful in weak acidic conditions and the change in rheological property of the smectite-water dispersion can be explained by the adsorption behavior of the sulfate anion to smectite.

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