Differential signal transmission cable, multi-core cable, and manufacturing method of differential signal transmission cable

A differential signal transmission cable comprising:

• two signal lines;
• an insulation layer covering a periphery of the two signal lines;
• and
• a plating layer covering the insulation layer,
• differential-to-common mode conversion quantity of the differential signal transmission cable having a maximum value of −26 dB or less, in a frequency band of 50 GHz or less,
• wherein the insulation layer comprises polyethylene or perfluoro ethylene propene copolymer,
• wherein when the insulation layer comprises polyethylene, crystallinity Xc represented by Formula 1 below is 0.744 or more,
• wherein when the insulation layer comprises perfluoro ethylene propene copolymer, crystallinity Xc represented by Formula 1 below is 0.47 or less
• X
• c
• =
• I
• c
• I
• c
• +
• I
• a
• [
• Formula
• ⁢
• ⁢
• 1
• ]
• where Ic in Formula 1 is an X-ray diffraction intensity of a crystalline component, and Ia is an X-ray diffraction intensity of an amorphous component.

A differential signal transmission cable comprising:

• two signal lines;
• an insulation layer covering a periphery of the two signal lines;
• and
• a plating layer covering the insulation layer,
• differential-to-common mode conversion quantity of the differential signal transmission cable having a maximum value of −26 dB or less, in a frequency band of 50 GHz or less,
• wherein the insulation layer comprises polyethylene or perfluoro ethylene propene copolymer,
• wherein when the insulation layer comprises polyethylene, crystallite size in a crystalline component of polyethylene is at least 18 nm or more,
• wherein when the insulation layer comprises perfluoro ethylene propene copolymer, crystallite size in a crystalline component of perfluoro ethylene propene copolymer is 13.6 nm or less.