| 摘要 |
PURPOSE:To reduce the variation ratio of resistance of a thermistor by adding CrO and FeO to oxides of Mn, Co and Cu having specific metallic element ratios. CONSTITUTION:A mixed oxide produced by compounding MnO, CoO and CuO in such a manner as to get a mixture containing 15-70atom% of Mn, 25-80atom% of Co and <=25atom% of Cu (in terms of metallic element: the sum of the elements is 100 atom%) is added with 0.01-10wt.% each of CrO and FeO and the composition is mixed in wet state. The mixture is dehydrated, dried, crushed, calcined, pulverized, mixed with a proper amount of a binder such as PVA, kneaded, granulated and compression-molded. The molded article is heat-treated to remove the binder and subjected to main calcination in air at a prescribed temperature to obtain a composition for thermistor exhibiting small variation ratio of resistance even after the use over a long period at a high temperature, i.e., at 125 deg.C. |
