Semiconductor binding tape and an electrical member wrapped therewith

Claim 1

An insulated electrical member, comprising at least one conductor wrapped with mica insulation and covered with a semiconducting binding tape, the whole being impregnated with a cured epoxy-styrene resin; wherein the binding tape comprises a porous, open weave substrate of electrically semiconducting fibrous strands; the fibrous strands coated with between about 15 to 40 weight percent of a carbon filled, completely thermoset, styrene resistant, protective varnish composition, the protective varnish composition consisting essentially of a cured, heat reactive phenolic alkyd admixture of 40 wt% to 75 wt% of a phenolic component and 60 wt% to 25 wt% of an alkyd component; said varnish composition containing between about 15 to 45 weight percent of electrically contacting carbon particles having a total internal and external surface area of up to about 600 square meters/gram, uniformly distributed therethrough, the interior of the carbon being substantially free of the varnish and resin, to provide fibrous strands that conduct electricity, said impregnated binding tape having a resistivity value of up to about 15,000 ohms/square.