| 摘要 |
<p>PURPOSE: To enhance the characteristics of limited voltage ratio by a method wherein the electrode material, which is obtained by adding the glass frit, formed by adding an Al-containing watersoluble inorganic metal compound or Al salt of high class fatty acid in the state as it is or as a liquid, to electrode paste, is printed and baked on a zinc oxide varistor. CONSTITUTION: An Al-containing inorganic metal compound or Al salt of high class fatty acid is dissolved into water, the dissolved material is added to the raw material containing B2 O3 and SiO2 , of 15.0wt.% for each of them and the remainder consisting of PbO. After the above-mentioned materials have been mixed and pulverized, the mixture is dissolved in a platinum crucible at 1000 to 1500 deg.C, and the mixture is virified by quenching. Then, the vitrified material is finely powdered, and lead borosilicate glass powder (glass frit) is obtained. The prescribed quantity (5.0wt.%) of the glass frit is mixed to the vehicle (30.0wt.%), in which ethyl cellusose is dissolved, together with Ag powder (65.0wt.%), and the electrode material for zinc oxide varistor is manufactured. This electrode material is coated on both surfaces of the zinc oxide lead varistor sintered body in such a manner that diameter of 10mm is obtained, and a baking operation is conducted at 800 deg.C for ten minutes.</p> |
