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In this report, optimization of the Zn content in Zn doped indium oxide (IZO) films deposited on plastic substrates at low temperature (20°C) was investigated in relation to variation of the Zn content from 0 to 15.9 at%. In the series of IZO films, 12.2 at% Zn doped indium oxide films, (IZO(12.2)), showed the lowest resistivity (2.9×10-4 Ωcm). The resistivity of IZO(12.2) films deposited on 100-µm-thick polycarbonate foil was approximately one half of that of ITO films (6×10-4 Ωcm) deposited under comparable conditions. IZO(12.2) films exhibited the lowest resistivity, high transmittance of over 85%, a rapid etching rate and good alkaline durability. The reason for rapid etching rate originates from the amorphous structure of IZO films. The thermal property of IZO(12.2) evaluated by a differential scanning calorimeter (DSC) clarified that the phase transformation from amorphous to crystalline began at 350°C, which meant the structure of IZO(12.2) remained amorphous for a practical temperature of the plastic substrate. Optical gap and Hall measurements revealed that the carrier density was decreased after annealing, whereas, the mobility was increased in relation to a trade off with the carrier density.

The wavelength dispersion of birefringence for uniaxially oriented copolycarbonate films containing positive and negative birefringent units has been examined by polarization-modulated transmission spectro-ellipsometry, as a function of copolymerization ratio and stretching parameters. The copolymers were synthesized from 2,2-bis(4-hydroxyphenyl)propane (BPA), 9,9-bis(4-hydroxy-3-methylphenyl)fluorene (BMPF) and phosgene by interfacial polycondensation. The films indicate reverse dispersion in the region of BMPF volume fraction from 0.65 to 0.80. The wavelength dispersion is controlled by the copolymerization ratio. The dispersion change of the 70 mol% BMPF copolycarbonate films as a function of stretching parameters is negligible. These behaviors are explained by the birefringence equation for a multicomponent system of the copolymer.

The birefringence dispersion of uniaxially oriented poly(2,6-dimethyl 1,4-phenylene oxide) (PPO)/atactic polystyrene (PS) blend films has been examined as a function of stretching temperature and draw ratio by polarization-modulated transmission spectro-ellipsometry. The normalized dispersion of Δn(450)/Δn(550) of the PPO/PS blends containing 25.6 wt% PPO decreases with increasing temperature between Tg and Tg+15°C at a draw ratio of 3, while it increases above Tg+15°C. The normalized birefringence dispersion as a function of draw ratio at Tg+15°C diverges at a draw ratio between 1.7 and 1.8. These phenomena can be explained by the change of the PS and PPO orientation functions in the birefringence equation of a multicomponent system on the assumptions that the intrinsic birefringence of PS and PPO is not changed by blending and the form birefringence is ignored.

The birefringence dispersion of uniaxially oriented poly(2,6-dimethyl 1,4-phenylene oxide) (PPO)/atactic polystyrene blend films has been investigated by polarization-modulated transmission spectro-ellipsometry measurements. The films show reverse birefringence dispersion in the region of PPO volume fraction from 0.21 to 0.29, where the birefringence is negative and close to zero, indicating ordinary refractive index dispersion. The reverse birefringence dispersion can be explained by the birefringence equation of a multicomponent system based on the preconditions that the intrinsic birefringence of each component in the blend is not changed and the form birefringence is ignored. Furthermore, it has been found that the orientation functions change depending on the volume fractions by the new method for obtaining orientation functions from birefringence dispersion.

The molecular orientation of an aromatic polycarbonate containing fluorene side chains was investigated by polarized infrared spectroscopy and birefringence analyses. The copolymers were synthesized from 2,2-bis(4-hydroxyphenyl)propane (BPA), 9,9-bis(4-hydroxy-3-methylpheny)fluorene (BMPF), and phosgene by interfacial polycondensation. The 1449-cm−1 band of the uniaxially oriented films, stretched at the glass-transition temperature (Tg) plus 5 °C, was assigned to various combinations of CC stretching and CH in-plane bending vibrations in the fluorene ring, and the transition moment angle was estimated to be 90°. The intrinsic birefringence of aromatic polycarbonate films with BMPF molar ratios ranging from 0.5 to 1 was obtained with the 1449-cm−1 band. The copolymer was estimated to show zero intrinsic birefringence at the BMPF molar ratio of 0.75, and the BMPF homopolymer showed negative intrinsic birefringence. A linear relationship between the volume fraction of BMPF units and the intrinsic birefringence indicated that the two monomer units of BPA and BMPF in each copolymer were not independent, and an intrinsic birefringence could be defined even in the copolymer. The sign of the photoelastic coefficient in the homopolymer with BMPF units was positive. The different signs of the photoelastic coefficient and the intrinsic birefringence suggest that the fluorene side-chain orientation induced by stress in the glass state is quite different from the orientation of the uniaxially oriented films stretched at Tg + 5 °C. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1554–1562, 2003

液晶表示装置用の位相差フィルムとして広く用いられているビスフェノールAポリカーボネート (BPAPC) 延伸フィルムの3次元屈折率と複屈折波長分散の相関およびIR, WAXSによる分子構造との相関を検討した. その結果, 通常の位相差フィルム製造条件であるTg近傍で延伸条件を変化させることによりBPAPCの分子配向を示す3次元屈折率が変化しても, 複屈折波長分散は変化しないことがわかった. また, 偏光IR, IRコンホメーション解析, WAXS測定で観測される特定の結合や原子団の配向状態と複屈折の関係は, 3次元屈折率が変化してもほとんど変化がないことがわかった. これらの結果から, 通常の位相差フィルム製造条件であるTg近傍で延伸されたBPAPCフィルムにおいては, 3次元屈折率測定から得られる分子配向変化が生じても, セグメントまたはそれに近い大きさでの微視的な分子構造変化が生じていないため, 複屈折波長分散が変化していないものと考えられる.