| 摘要 |
PURPOSE:To improve productivity of a gas-sensitive element of excellent characteristics, by allowing mixed existence of larger air-hole member and smaller air- hole member in a gas-responding body, allowing a piece of catalytic metal to be supported in the smaller member and not allowing the larger member to support it or allowing to support only a smaller quantity of it than the smaller member. CONSTITUTION:By sintering TiO2 at various temperatures, smaller air-hole member ( I ) and larger air-hole member (II) are obtained. After application of oilophile surface treatment to the smaller air-hole member ( I ), it is crushed into coarse powder of 4-10mum and the larger air-hole member (II) into particles of 200-300 mesh. To 20g of smaller air-hole member I , 0.9g of emulsifier, 500cc of tetraethylene and 2-5mol% Pt are added with following mixing to obtain oily slurry, O. To 400g of larger air-hole member II, 300cc of water and a small quantity of Pt-black are added with following mixing to obtain watery slurry, W. W and O are mixed and this W/O emulsion is subjected to atomization and drying. An element 1 including a Pt electrode wire 2 is formed with said powder and subjected to sintering at 1,200 deg.C for an hour. By these processes, a productivity in mass production of gas-sensitive element is improved. |
