Signal transmission cable
A signal transmission cable is provided with a conductor, an insulator covering around the conductor, a shield layer covering around the insulator, a sheath covering around the shield layer, and a plating base layer is provided between the insulator and the shield layer to cover around the insulator. The shield layer has a plating layer provided to cover the plating base layer to be in contact with an outer peripheral surface of the plating base layer. A surface roughness of an outer peripheral surface of the plating layer is less than a surface roughness of an inner peripheral surface of the plating layer.
1. A signal transmission cable, comprising:
a conductor;
an insulator covering around the conductor;
a shield layer covering around the insulator;
a sheath covering around the shield layer; and
a plating base layer is provided between the insulator and the shield layer to cover around the insulator,
wherein the shield layer comprises a plating layer provided to cover the plating base layer to be in contact with an outer peripheral surface of the plating base layer,
wherein a surface roughness of an outer peripheral surface of the plating layer is less than a surface roughness of an inner peripheral surface of the plating layer,
the outer peripheral surface of the plating base layer is roughened to have a surface roughness of 2 μm or more, and
the arithmetic mean roughness Ra of the inner peripheral surface of the plating layer is 2 μm or more and the arithmetic mean roughness Ra of the outer peripheral surface of the plating layer is less than 2 μm, and
wherein a thickness of the plating layer is 2 μm or more and 5 μm or less.
2. The signal transmission cable according to claim 1 , wherein a thickness of the plating base layer is less than a thickness of the insulator.
3. The signal transmission cable according to claim 1 , wherein the plating layer is formed on the plating base layer, which is composed of a resin.
4. The signal transmission cable according to claim 1 , wherein a distance between the conductor and the plating layer is kept substantially constant.
5. The signal transmission cable according to claim 1 , wherein the plating base layer flexibly deforms in response to bending.
6. A signal transmission cable, comprising:
a conductor;
an insulator covering around the conductor,
a shield layer covering around the insulator;
a sheath covering around the shield layer, and
a plating base layer is provided between the insulator and the shield layer to cover around the insulator,
wherein the shield layer comprises a plating layer provided to cover the plating base layer to be in contact with an outer peripheral surface of the plating base layer,
wherein a surface roughness of an outer peripheral surface of the plating layer is less than a surface roughness of an inner peripheral surface of the plating layer,
the outer peripheral surface of the plating base layer is roughened to have a surface roughness of 2 μm or more, and
the arithmetic mean roughness Ra of the inner peripheral surface of the plating layer is 2 μm or more and the arithmetic mean roughness Ra of the outer peripheral surface of the plating layer is less than 2 μm, and
wherein the insulator comprises a fluoropolymer and the plating base layer comprises polyethylene or polypropylene.