A New Method of Insulating Copper Wire.

Progress, Volume II, Issue 2, 1 December 1906, Page 70

A New Method of Insulating Copper Wire.

A cheap and effective method of insulating conductors for use in house wiring and other purposes is described by the Electrotechmker. The surface of the copper is first treated by passing it through a solution of proto-sulphide of potassium, and so exposing it to the action of sulphuretted hydrogen vapour. When the copper has attained a bluishblack tinge, it is exposed to the air until it becomes quite black, and finally it is well washed in water. When dry, it is only necessary to coat the wire with a suitable varnish made of good linseed oil ; to do this the wire is drawn through a bath of the melted varnish, and dried. The resulting covering is perfectly continuous and impervious to moisture, and its flexibility, though not so great as that of gutta-percha, is ample for ordinary purposes