INSULATED WIRE FOR WINDING AND METHOD OF MANUFACTURING COIL

PROBLEM TO BE SOLVED: To provide an insulated wire for winding which is suitable as windings requiring a high space factor capable of restraining electric field concentration at a corner section and improving corona discharge starting voltage and breakdown voltage. SOLUTION: In the insulated wire T1 for winding having an insulating coated layer 2 of at least one layer made of a resin on an outer periphery of a conductor 1 with a cross-sectioned approximately square, a thickness t (mm) of the insulating coated layer 2 coated on a flat section of the conductor 1, a radius R1 (mm) of curvature of the corner section 3 of the conductor 1, and a radius R2 (mm) of curvature of the corner section 4 of the insulating coated layer 2 satisfy an expression of: 0