| 摘要 |
<p>PURPOSE:To prevent an electrical characteristic from being lowered when a high-resistance layer is formed by a method wherein side faces of a sintered substance of a molded substance composed mainly of zinc oxide are coated with a substance composed mainly of an inorganic high polymer or an organic metallic compound and this substance is pyrolyzed and the like at a comparatively low temperature. CONSTITUTION:A raw material is prepared in such a way that 0.5mol% each of bismuth oxide, manganese dioxide and the like and 1mol% each of cobalt oxide and the like as auxiliary components are added to zinc oxide. Then, this mixture is sprayed, granulated, pressurized and molded to a prescribed shape such as a disk or the like; a sintered substance 1 is formed. Side faces of the sintered substance 1 are coated, by using a spray gun, with a butanol solution of, e.g., tributoxyaluminum whose solid component is an inorganic high polymer of 80wt.%. This coated sintered substance 1 is dried and hardened at a temperature from room temperature to 350 deg.C for 12 to 24 hours; high- resistance layers 2 are formed. After that, both end faces of the sintered substance 1 are polished; aluminum is flame-sprayed to both end faces; electrodes 3 are formed.</p> |
