Patent ID: 6749891
Filing Date: 2004-06-15
Classification: H01C,Y10T

Abstract:
A method of manufacturing a zinc oxide varistor comprising:(a) a first process of forming a varistor element, said varistor element contains zinc oxide as a main component, and (b) a second process of sintering said varistor element, wherein by sintering said varistor element, said varistor element is sintered, and a zinc compound having at least one of acid resistance and alkali resistance is precipitated and formed on the surface of said varistor elements, wherein, in the first process, said varistor element further contains bismuth compound and silicon compound as sub-components, and the second process includes a step of precipitating Znâ€”Siâ€”O based compound as at least part of the zinc compound, wherein said silicon compound is contained ranging from 1 mol % to 15 mol % in terms of Si, wherein the sintering temperature in the second process ranges from 1000Â° C. to 1400Â° C., wherein the second process includes a step of storing said varistor element into a sheath and sintering same while rotating said sheath, and wherein said sheath stores at least one powder selected from the group consisting of Al2O3, MgO, ZrO2, ZnO and NiO together with said varistor element.