Insulation-coated electric conductor

Abstract

A multilayer insulation-coated electric conductor for a coil constituting a circuit by forming a welded portion in the coil, wherein at least one layer of the multilayer insulation-coating layers of the coated metal conductor is composed of at least one resin selected from the group consisting of a polyimide resin, a polyesterimide resin, and an H-class polyester resin.

What is claimed is:  
     
         1 . A multilayer insulation-coated electric conductor for a coil constituting a circuit by forming a welded portion in the coil, wherein at least one layer of the multilayer insulation-coating layers of the coated metal conductor is composed of at least one resin selected from the group consisting of a polyimide resin, a polyesterimide resin, and an H-class polyester resin.  
     
     
         2 . The coated metal conductor according to  claim 1 , wherein the lowermost layer of the insulation-coating layers of the multilayer insulation-coated electric conductor is composed of a polyamideimide resin.  
     
     
         3 . The coated metal conductor according to  claim 1 , wherein the uppermost layer of the multilayer insulation-coating layers is composed of a polyamideimide resin, and wherein an under insulation-coating layer adjacent to the uppermost layer is composed of at least one resin selected from the group consiting of a polyimide resin, a polyesterimide resin, and an H-class polyester resin.  
     
     
         4 . The coated metal conductor according to  claim 3 , wherein the lowermost layer of the insulation-coating layers of the multilayer insulation-coated electric conductor is composed of a polyamideimide resin.  
     
     
         5 . The coated metal conductor according to  claim 1 , wherein the metal conductor is low-oxygen copper with an oxygen content of 30 ppm or lower, or an oxygen-free copper.  
     
     
         6 . The coated metal conductor according to  claim 1 , wherein a cross-section of the conductor has a shape other than round.  
     
     
         7 . The coated metal conductor according to  claim 1 , wherein the cross-section of the conductor has a rectangular shape.  
     
     
         8 . The coated metal conductor according to  claim 1 , wherein wax or a lubricant is dispersed in or mixed with a resin for forming the uppermost layer of the multilayer insulation-coating layers.