Copper-Oxide used in glaze for porcelain insulators

Copper-Oxide Glaze

for Insulators

Another broadcasting nuisance has been forced off the air. Porcelain insulators have in some cases been serving as miniature broadcasting stations because the high-resistance contact existing between the copper conductor and the porcelain gives rise to arc-type 60-cycle charging currents. The solution is, paradoxially, to make the insulator more conducting, at least in the region of the conductor. A copper-oxide coating is applied to the insulator top during the process of its manufacture. This glaze is subsequently reduced to metallic copper by a chemical process and then given a coating of tin to protect it from abrasion, so that the conductor makes intimate contact with the porcelain and eliminates all arcing.