VARISTOR, SURGE ABSORBING ELEMENT, FORMATION OF PROTECTIVE FILM AND BISMUTH BOROSILICATE-BASED GLASS COMPOSITION

摘要

PURPOSE: To improve the working life characteristics of a varistor by improving the composition of a protective film coating its surface to raise the durability to repeated applications of surges. ;CONSTITUTION: Both surfaces of a sintered compact 4 with voltage nonlinearity consisting mainly of ZnO is equipped with electrodes 6, 6 along with coating the whole surface of the sintered compact 4 with a protective film 8, thus obtaining the objective varistor 2. In this case, the protective film 8 is made up from noncrystalline bismuth borosilicate (B₂O₃-SiO₂-Bi₂O₃-ZnO)-based glass.;COPYRIGHT: (C)1994,JPO&Japio