A wire rod is mainly composed of copper, and an oxidation degree measured on a surface of the wire rod using Raman spectral analysis is less than 25, in which measurement of the oxidation degree is performed by mapping Raman spectra under conditions described below, a histogram is created from peak areas of Raman spectral peaks in respective pixels of an obtained mapping image, an average value of a plurality of the peak areas is determined from the histogram, and the average value is measured as the oxidation degree, and a plurality of the Raman spectral peaks are peaks attributed to a lattice vibration of a vibrational mode 2E.sub.u of Cu.sub.2O, the histogram has a horizontal axis representing 256 levels into which a range from minimum to maximum of the plurality of the peak areas are divided, and a vertical axis representing a frequency, which is a number of pixels in each level.

An insulated wire includes a conductor having an elongated shape and an insulating coating. The insulating coating is provided around the conductor. The insulating coating is formed by laminating multiple insulating layers, each of which includes pores.

A manufacturing apparatus for an enameled copper wire of the present disclosure includes: a coating material application section configured to apply a coating material to a surface of a conductor in traveling; a baking section configured to bake the conductor to which the coating material has been applied; and a dehumidifying section configured to set an absolute humidity in a space in which the manufacturing apparatus is installed to 18 g/m.sup.3 or less.

The present invention relates to the technical field of subsea power cables. More specifically, the invention relates to a subsea power cable comprising at least one cable core, the cable core comprising a metal conductor, the metal conductor comprising at least one metal wire, wherein a section of the at least one metal wire along the longitudinal direction is surrounded with a material of low electrical conductivity.