Disclosed are a corona-resistant enameled round wire and preparation method therefor. The corona-resistant enameled round wire is suitable for electric vehicle motors and comprises a copper conductor and an insulating layer, wherein the insulating layer clads the copper conductor and comprises, in sequence from inside to outside, a corona-resistant polyamideimide coating, a corona-resistant special resin coating, a corona-resistant polyimide coating, a corona-resistant modified silicone resin coating, and a corona-resistant polyamideimide coating.

An insulated electric conductor includes a flat or round wire made of one or more electrically conductive materials, the flat or round wire having an exterior surface that is free of an oxide layer; and an insulating layer adhering directly to the oxide-layer-free exterior surface to form a coating around the oxide-layer-free exterior surface, the insulating layer being made of at least one thermoplastic material which provides electrical insulation. The flat or round wire is designed to conduct an electrical current.

A silica sol dispersed in a nitrogen-containing solvent and a silica-containing resin composition containing a nitrogen atom-containing polymer. A silica sol including silica particles containing aluminum atoms and having an average primary particle diameter of 5 to 100 nm, the silica particles being dispersed in a nitrogen-containing solvent, wherein the aluminum atoms are bonded to the surfaces of the silica particles in an amount in terms of Al.sub.2O.sub.3 of 800 to 10,000 ppm/SiO.sub.2. The silica particles are bonded to a silane compound or a hydrolysate of the silane compound. The nitrogen-containing solvent is an amide solvent. The nitrogen-containing solvent is dimethylacetamide, dimethylformamide, N-methylpyrrolidone, or N-ethylpyrrolidone. The insulating resin composition includes the silica sol and a nitrogen-containing polymer. The nitrogen-containing polymer is polyimide, polyamide, polyamic acid, polyamideimide, polyetherimide, or polyesterimide. An insulation-coated conductor wire produced by insulation coating of a conductor wire with the insulating resin composition.

Disclosed is an enameled wire comprising a metal wire, in particular a copper wire, which is coated with an electrically insulating varnish containing at least one varnish polymer. Fluorine atoms are bonded to the outer surface of the varnish by substitution or radical substitution as a result of a treatment of the outer surface with fluorine or fluorine gas.

A silica sol dispersed in a nitrogen-containing solvent and a silica-containing resin composition containing a nitrogen atom-containing polymer. A silica sol including silica particles containing aluminum atoms and having an average primary particle diameter of 5 to 100 nm, the silica particles being dispersed in a nitrogen-containing solvent, wherein the aluminum atoms are bonded to the surfaces of the silica particles in an amount in terms of Al.sub.2O.sub.3 of 800 to 10,000 ppm/SiO.sub.2. The silica particles are bonded to a silane compound or a hydrolysate of the silane compound. The nitrogen-containing solvent is an amide solvent. The nitrogen-containing solvent is dimethylacetamide, dimethylformamide, N-methylpyrrolidone, or N-ethylpyrrolidone. The insulating resin composition includes the silica sol and a nitrogen-containing polymer. The nitrogen-containing polymer is polyimide, polyamide, polyamic acid, polyamideimide, polyetherimide, or polyesterimide. An insulation-coated conductor wire produced by insulation coating of a conductor wire with the insulating resin composition.

An insulating composition having a polymer resin, a nanoclay, and one or more nanofillers. The insulating composition has a thermal conductivity of greater than about 0.8 W/mK, a dielectric constant of less than about 5, a dissipation factor of less than about 3%, and a breakdown strength of greater than about 1,000V/mil. The insulating composition has an endurance life of at least 400 hours at 310 volts per mil.

A cover for a cable harness including: (i) a first layer comprising a first color; (ii) a second layer layered adjacent to the first layer, the second layer comprising a second color that is different than the first color; and (iii) an adhesive layer adhered to the first layer, at least a portion of the adhesive is not covered by the second layer. The first color can black, while the second color is white. The second layer comprises fibers that can be substantially free of dye. At least one of the first layer and the second layer can be polyethylene terephthalate. The cover can cover a plurality of cables of a cable harness. If wear forms a hole through the first layer, the second color of the second layer is visible from an environment external to the covered cable harness through the hole through the first layer.

An insulated conductor of the present invention is an insulated conductor having a conductor and an insulating film provided on a surface of the conductor, in which the insulating film has a low-concentration fluorine layer disposed on a surface side of the conductor and a high-concentration fluorine layer disposed on at least a part of an outside surface of the low-concentration fluorine layer, the low-concentration fluorine layer includes a cured product of a thermosetting resin and a fluororesin and has a fluorine atom content relatively lower than that of the high-concentration fluorine layer, and the high-concentration fluorine layer includes a cured product of a thermosetting resin and a fluororesin and has a fluorine atom content relatively higher than that of the low-concentration fluorine layer.

A wire harness includes a multi-core cable including a group of cables composed of a plurality of cables, and a sheath provided around the group of cables, and a resin mold covering the group of cables at a cable branching portion where the group of cables exposed from an end of the sheath of the multi-core cable are branched. An outermost layer of each cable constituting the group of cables includes polyolefin or thermoplastic polyurethane. When the sheath includes polyolefins, the group of cables includes at least one cable including an outermost layer including thermoplastic polyurethane. When the sheath includes thermoplastic polyurethane, the group of cables includes at least one cable having an outermost layer comprising polyolefin. The resin mold includes a resin composition of a polymer alloy of a first polymer including at least one of polyamide polymer, polyester polymer, and thermoplastic polyurethane and a second polymer including polyolefin.

Ribbon cables including a plurality of spaced apart substantially parallel conductors extending along a length of the cable and arranged along a width of the cable, and first and second insulative layers disposed on opposite sides of and substantially coextensive with the plurality of conductors along the length and width of the cable are described. Each insulative layer may be adhered to the conductors and may include alternating substantially parallel thicker and thinner portions extending along the length of the cable. The thicker portions of the first and second insulative layers are substantially aligned in one to one correspondence. Each corresponding thicker portion of the first and second insulative layers have at least one conductor in the plurality of conductors disposed therebetween. The thicker portions may have an effective dielectric constant less than 2.