Medical guide wire

A medical guide wire comprising

• a core wire having a distal end-side small-diameter portion and a proximal end-side large-diameter portion having a larger outside diameter than the outside diameter of the distal end-side small-diameter portion, and
• a coil spring installed on an outer periphery of the distal end-side small-diameter portion of the core wire along an axial direction, having a front end-side small-diameter portion, a rear end-side large-diameter portion having a larger outside diameter of coil than that of the front end-side small-diameter portion and a tapered portion located between the front end-side small-diameter portion and the rear end-side large-diameter portion, and fixed to the core wire at at least the front end portion and rear end portion thereof, wherein
• the length of the front end-side small-diameter portion of the coil spring is 5 to 100 mm, and the outside diameter of coil thereof is at most 0.012 inch,
• the front end portion of the coil spring is fixed to the core wire by Au—Sn solder, and
• the length of a distal end portion stiffened by the Au—Sn solder is 0.1 to 0.5 mm.

A medical guide wire comprising

• a core wire having a distal end-side small-diameter portion and a proximal end-side large-diameter portion having a larger outside diameter than the outside diameter of the distal end-side small-diameter portion, and
• a coil spring installed on an outer periphery of the distal end-side small-diameter portion of the core wire along an axial direction, having a front end-side small-diameter portion, a rear end-side large-diameter portion having a larger outside diameter of coil than that of the front end-side small-diameter portion and a tapered portion located between the front end-side small-diameter portion and the rear end-side large-diameter portion, and fixed to the core wire at at least the front end portion and rear end portion thereof, wherein
• the length of the front end-side small-diameter portion of the coil spring is 5 to 100 mm, and the outside diameter of coil thereof is at most 0.012 inch,
• the front end portion of the coil spring is fixed to the core wire by Au—Ge solder, and
• the length of a distal end portion stiffened by the Au—Ge solder is 0.1 to 0.5 mm.