New varistor ceramic composition

摘要

A novel ceramic composition consists of zinc oxide and a compound oxide of formula Zn2SnO4. Preferably, the composition contains 0.01-20 (especially 1-10) mol% Zn2SnO4 with optional additions of bismuth, cobalt and manganese oxides. Also claimed are a ceramic and a varistor having the above composition and including internal and external electrodes electrically connected together. Further claimed is production of a varistor starting material by heating a mixture of zinc oxide and tin oxide to obtain the compound oxide which is then combined with zinc oxide and heated.