Provided are a CNT forest having favorable spinning properties, and as a method for producing such a CNT forest, a production method in which CNT forest 45 is formed by applying, as deposition base surface 44, a surface including at least one part of inner surface 43 in opening substrate 40 having interior space 42 communicating with an outside through open portion 41, and CNT forest 45 has spinnable portion 47 at end 46 on a side of open portion 41.

Provided are a CNT forest having favorable spinning properties, and as a method for producing such a CNT forest, a production method in which CNT forest 45 is formed by applying, as deposition base surface 44, a surface including at least one part of inner surface 43 in opening substrate 40 having interior space 42 communicating with an outside through open portion 41, and CNT forest 45 has spinnable portion 47 at end 46 on a side of open portion 41.

The present invention discloses a fiber surface treatment composition, characterized in that the composition is comprised of a silane coupling agent, a polymer and a water repellent agent, wherein the polymer is a copolymer of a polyurethane/acrylic acid polymer, wherein the acrylic polymer is selected from the group consisting of polyacrylic acid, polyacrylates or acrylic acid-acrylic acid ester copolymers. The invention also discloses an insulating fiber having the composition on its surface, the preparation method for it, and an insulating yarn and an insulated cord. The insulated fibers, yarns and ropes of the invention have the advantages of moisture resistance, washing resistance, ultraviolet aging resistance and the like. Particularly, the insulated ropes can be applied to the charging work of transmission lines, especially the UHV transmission lines.

The present invention discloses a fiber surface treatment composition, characterized in that the composition is comprised of a silane coupling agent, a polymer and a water repellent agent, wherein the polymer is a copolymer of a polyurethane/acrylic acid polymer, wherein the acrylic polymer is selected from the group consisting of polyacrylic acid, polyacrylates or acrylic acid-acrylic acid ester copolymers. The invention also discloses an insulating fiber having the composition on its surface, the preparation method for it, and an insulating yarn and an insulated cord. The insulated fibers, yarns and ropes of the invention have the advantages of moisture resistance, washing resistance, ultraviolet aging resistance and the like. Particularly, the insulated ropes can be applied to the charging work of transmission lines, especially the UHV transmission lines.

Provided are a rubber article reinforcing steel wire that is superior in bending fatigue properties to the related art and has a flat cross-sectional shape, and a rubber article using the wire. In a rubber article reinforcing steel wire 10, a major diameter and a minor diameter are substantially perpendicular to each other. Assuming that the major diameter is W, the minor diameter is T, a straight line that passes through a center of the major diameter in a width direction and is parallel to a minor diameter direction is L1, a straight line that passes through a center of the minor diameter in a width direction and is parallel to a major diameter direction is L2, an intersection point of the L1 and the L2 is a center point C, a region within a half of a distance from the center point C to a surface is a central region Rc, and a region outside the central region Rc is a surface layer region Rs, a Vickers hardness Hvc of the central region Rc is more than a Vickers hardness Hvs of the surface layer region Rs; and assuming that a Vickers hardness on the L1 in the surface layer region Rs is Hv1, and a Vickers hardness on the L2 in the surface layer region Rs is Hv2, relationships represented by Hvc−Hv1≦150, Hvc−Hv2≦150, Hv1/Hvc×100≧85.11, and Hv2/Hvc×100≧79.84 are satisfied.

Provided are a rubber article reinforcing steel wire that is superior in bending fatigue properties to the related art and has a flat cross-sectional shape, and a rubber article using the wire. In a rubber article reinforcing steel wire 10, a major diameter and a minor diameter are substantially perpendicular to each other. Assuming that the major diameter is W, the minor diameter is T, a straight line that passes through a center of the major diameter in a width direction and is parallel to a minor diameter direction is L1, a straight line that passes through a center of the minor diameter in a width direction and is parallel to a major diameter direction is L2, an intersection point of the L1 and the L2 is a center point C, a region within a half of a distance from the center point C to a surface is a central region Rc, and a region outside the central region Rc is a surface layer region Rs, a Vickers hardness Hvc of the central region Rc is more than a Vickers hardness Hvs of the surface layer region Rs; and assuming that a Vickers hardness on the L1 in the surface layer region Rs is Hv1, and a Vickers hardness on the L2 in the surface layer region Rs is Hv2, relationships represented by Hvc−Hv1≦150, Hvc−Hv2≦150, Hv1/Hvc×100≧85.11, and Hv2/Hvc×100≧79.84 are satisfied.

Provided is a steel cord for rubber article reinforcement which has excellent corrosion resistance and productivity without deterioration of adhesion with rubber. A steel cord (1) for rubber article reinforcement, in which plural steel filaments (2) are twisted together, includes: a core having at least one core filament (2c); and a sheath having at least one sheath layer formed by twisting at least one sheath filament (2s) around the core. In this steel cord (1), brass plating is performed on the steel filaments (2) and zinc plating is further performed on the outer circumference of the brass plating of the core filament (2c), and the steel filaments (2) have a diameter d of 0.1 mm to 0.6 mm.

Provided is a steel cord for rubber article reinforcement which has excellent corrosion resistance and productivity without deterioration of adhesion with rubber. A steel cord (1) for rubber article reinforcement, in which plural steel filaments (2) are twisted together, includes: a core having at least one core filament (2c); and a sheath having at least one sheath layer formed by twisting at least one sheath filament (2s) around the core. In this steel cord (1), brass plating is performed on the steel filaments (2) and zinc plating is further performed on the outer circumference of the brass plating of the core filament (2c), and the steel filaments (2) have a diameter d of 0.1 mm to 0.6 mm.

A method is provided for making a fiber wire having a fiber bundle core and a polymer jacket. The method includes rotating a spool of fiber bundle about a first rotational axis to progressively unwind the fiber bundle from the spool. The fiber bundle includes a plurality of continuous synthetic fiber filaments. While the spool is rotated about the first rotational axis, the spool is simultaneously rotated about a second rotational axis to thereby twist the unwound fiber bundle about its longitudinal axis. The method further includes coating the twisted fiber bundle with a molten polymer, and permitting the molten polymer to cool to define a flexible outer jacket that encapsulates the twisted fiber bundle.

A method is provided for making a fiber wire having a fiber bundle core and a polymer jacket. The method includes rotating a spool of fiber bundle about a first rotational axis to progressively unwind the fiber bundle from the spool. The fiber bundle includes a plurality of continuous synthetic fiber filaments. While the spool is rotated about the first rotational axis, the spool is simultaneously rotated about a second rotational axis to thereby twist the unwound fiber bundle about its longitudinal axis. The method further includes coating the twisted fiber bundle with a molten polymer, and permitting the molten polymer to cool to define a flexible outer jacket that encapsulates the twisted fiber bundle.