| 摘要 |
<p>PURPOSE:To improve opening and closing surge resistance even if it is formed with electrodes, by previously treating a molded form thermally at a specific temperature, then impregnating it with second additive having function for increasing grain growth suppression and/or mechanical strength from the outer peripheral side of the form, and baking it. CONSTITUTION:In a case in which zinc oxide as a main component and at least one type of first additive exhibiting voltage nonlinearity are added, mixed, molded and baked to manufacture a voltage nonlinear resistor, a molded form is previously treated thermally at 700-950 deg.C, then impregnated with second additive having function for increasing grain growth suppression and/or mechanical strength from the outer peripheral side of the form, and then baked. For example, ZnO as a main component and Bi2O3, Sb2O3, Cr2O3 of predetermined amount are added, preliminarily baked at 700-950 deg.C, the molded form is then masked at both end faces, and dipped in ethyl silicate. Then, the ethyl silicate impregnated into the form is hydrolyzed, the form is then temporarily baked at 980 deg.C, then coated with inorganic substance for forming a high resistance layer on the side face, and then baked at 1150 deg.C.</p> |
