Shigenobu Sobajima

Production and Properties of Transparent Electroconductive Coating on Polyester Film

Indium oxide was vacuum deposited onto the surface of polyester films. The oxide is reduced to In2O by sublimation and a thin opaque electroconductive coating is obtained. The coating was thermally oxidized in the air below 200°C. The resulting film showed transmission of 80 to 95% for visible light and surface resistance of 200 to 500 ohm/sq. Small amount of stannic oxide doped to the indium oxide improves the surface resistance and determines the optimum temperature of the substrate. The mechanism of formation and the properties of the coating were discussed.

Control of Oxygen Deficiency in Superconducting Y1Ba2Cu3O7-y Films Using a Solid-State Electrolyte

Y1Ba2Cu3O7-y (YBCO) films deposited on YSZ are coated with MgO films in order to isolate the YBCO film from the atmosphere. An electrochemical technique using a solid-state electrolyte is applied to this airtight structure to control the density of the oxygen deficiency y in the YBCO film. The resistivity of the YBCO film at 500°C is found to be reversibly changed by the applied current. The change of y by the applied current is confirmed by the change of the lattice parameter c. From the temperature dependence of the resistivity of the film, it is shown that Tc could be controlled and fixed by using this technique.

Transparent Heat Insulating Coatings On A Polyester Film

Multi-layer coatings of metal-dielectric type were prepared on a poly (ethylene terephthalate) (PET) film using chemical and physical preparation techniques. Hydrolysis of tetrabutyl titanate (TBT) followed by condensation gave rise to well-controlled transparent dielectric layers with relatively high refractive index and a silver layer was prepared by vacuum evaporation. Changes of chemical coating condition gave various types of optical characteristics. This film reduces energy dissipation from a single windowpane by around 35%.