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.

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.

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.

Amine-substituted copolymers that may include an amine-substituted 2-amino-ethan-1-ol moiety. Polyamic acids and polyimides, which may be formed by contacting an amine substituted copolymer with a dianhydride, or a dianhydride and a diamine. Articles, such as wires, having a surface on which a polyimide is disposed. Methods for forming polymers.

A signal transmission cable is provided with a conductor, an insulator covering around the conductor, a shield layer covering around the insulator, a sheath covering around the shield layer, and a plating base layer is provided between the insulator and the shield layer to cover around the insulator. The shield layer has a plating layer provided to cover the plating base layer to be in contact with an outer peripheral surface of the plating base layer. A surface roughness of an outer peripheral surface of the plating layer is less than a surface roughness of an inner peripheral surface of the plating layer.

A signal transmission cable is provided with a conductor, an insulator covering around the conductor, a shield layer covering around the insulator, a sheath covering around the shield layer, and a plating base layer is provided between the insulator and the shield layer to cover around the insulator. The shield layer has a plating layer provided to cover the plating base layer to be in contact with an outer peripheral surface of the plating base layer. A surface roughness of an outer peripheral surface of the plating layer is less than a surface roughness of an inner peripheral surface of the plating layer.

A power cable 1 according to the present invention contains a propylene-based resin in a specific range as an insulating layer 13, and has a specific relationship between the cooling rate X at the time of manufacturing the interface portion in the insulating layer 13 with an inner semiconductive layer 12 and the cooling rate Y at the time of manufacturing the central portion of the insulating layer 13. Thus, not only the surface of the insulating layer 13 but also the inside of the insulating layer 13, the interface portion in the insulating layer 13 with the inner semiconductive layer 12, and the inside thereof are reliably cooled and cured. Therefore, the metal conductor 11 is not displaced from the center of the power cable 1 due to its own weight, and uneven thickness is less likely to occur.

A power cable 1 according to the present invention contains a propylene-based resin in a specific range as an insulating layer 13, and has a specific relationship between the cooling rate X at the time of manufacturing the interface portion in the insulating layer 13 with an inner semiconductive layer 12 and the cooling rate Y at the time of manufacturing the central portion of the insulating layer 13. Thus, not only the surface of the insulating layer 13 but also the inside of the insulating layer 13, the interface portion in the insulating layer 13 with the inner semiconductive layer 12, and the inside thereof are reliably cooled and cured. Therefore, the metal conductor 11 is not displaced from the center of the power cable 1 due to its own weight, and uneven thickness is less likely to occur.

A cable includes: core wires comprising a pair of inner conductors and an inner insulating layer separately covered around each of the pair of inner conductors; a wrapping layer covering the core wires; a shielding layer covering the wrapping layer; and an outer coating layer covering the shielding layer; wherein the wrapping layer comprises a first wrapping layer covering the core wires and a second wrapping layer covering the first wrapping layer.

An Ethernet cable that includes a pair of cores including a single-wire conductor and an insulator covering the single-wire conductor; and an armoring layer entirely covering the pair of cores, wherein the pair of cores are twisted together to have a twist pitch (P1) in a cable length direction satisfying certain characteristics.