Enameled wires

Claim 1

An insulated enameled wire which exhibits a fusing function to short circuit with adjacent wires due to the provision of an insulating thermoplastic straight chain polyurethane layer thereon which melts fuses at an inside temperature of about 150° to 250° C. without substantially generating smoke thereby permiting short circuiting with adjacent wires, which comprises a conductive wire having coated thereon said insulating thermoplastic straight chain polyurethane layer which is formed by coating a layer consisting essentially of a member selected from the group consisting of the following: components (i) and (ii); components (i) and (iii); or components (i), (ii) and (iii) as defined below; (i) a polyurethane having a terminal hydroxyl group prepared from at least one aliphatic diol, at least one diisocyanate compound selected from the group consisting of a diisocyanate and a blocked diisocyanate in less than about an equimolar amount of said aliphatic diol; (ii) a polyurethane having a terminal blocked isocyanate group prepared from at least one diisocyanate compound selected from the group consisting of a diisocyanate and a blocked diisocyanate, at least one aliphatic diol in less than about an equimolar amount of said diisocyanate, and a blocking agent for an isocyanate group; and (iii) a blocked diisocyanate, wherein at least a portion of said diisocyanate compound in (i), (ii) and (iii) is an aromatic diisocyanate on said conductive wire and then baking the thus coated conductive wire to yield said insulating thermoplastic straight chain polyurethane layer.