Patent ID: 7800000

Claim:
A superconducting-cable core, comprising a superconducting conductor and an insulating layer covering the outer circumference of the superconducting conductor; the superconducting-cable core being classified longitudinally into a cable portion and a jointing-structure-forming portion that is located at each end of the cable portion and that serves as the portion in which a complementary insulating structure is formed when jointed with another conducting member; of the superconducting-cable core, the jointing-structure-forming portion being at least within the range from the end of the superconducting-cable core to the end of the complementary insulating structure; the jointing-structure-forming portion having an insulating layer whose electric insulation performance is higher than that of the insulating layer of the cable portion, wherein: (a) the insulating layer of the jointing-structure-forming portion is provided with a main insulating layer and an inner insulating layer placed between the main insulating layer and the superconducting conductor; and (b) the inner insulating layer has a dielectric constant higher than that of the main insulating layer.