In one embodiment of the present invention as used for impregnating a composite tape (56) with HTC particles provides for permeating a fabric layer (51) of the composite tape with HTC particles and impregnating an impregnating resin into the composite tape through the fabric layer (51). At least 5% of the HTC particles permeated into the fabric layer are carried out of the fabric layer and into a mica layer (52) bound to the fabric layer by the impregnating resin. In some embodiments the impregnating resin itself contains HTC particles.