A brass-plated steel cord 1A is immersed in an organic solvent 13. The steel cord that was immersed in the organic solvent 13 is immersed in an aqueous alkaline solution 22. Next, the steel cord 1A that was immersed in the aqueous alkaline solution 22 is immersed in an aqueous silane coupling solution 32. Finally, the steel cord 1A that was immersed in the aqueous silane coupling solution 32 is heated. Thus is manufactured a steel cord 1B equipped with the silane coupling agent, wherein the silane coupling agent is excellently bonded to the surface.

A brass-plated steel cord 1A is immersed in an organic solvent 13. The steel cord that was immersed in the organic solvent 13 is immersed in an aqueous alkaline solution 22. Next, the steel cord 1A that was immersed in the aqueous alkaline solution 22 is immersed in an aqueous silane coupling solution 32. Finally, the steel cord 1A that was immersed in the aqueous silane coupling solution 32 is heated. Thus is manufactured a steel cord 1B equipped with the silane coupling agent, wherein the silane coupling agent is excellently bonded to the surface.

A tire includes a steel cord having a plated coating layer, rubber covering the steel cord, the plated coating layer including Cu and Zn, and a bonding layer including Cu.sub.2S and CuS provided closer to the rubber than an interface between the steel cord and the rubber, wherein a molar ratio Cu.sub.2S/CuS of Cu.sub.2S and CuS included in the bonding layer is 1.0 or higher.

A tire includes a steel cord having a plated coating layer, rubber covering the steel cord, the plated coating layer including Cu and Zn, and a bonding layer including Cu.sub.2S and CuS provided closer to the rubber than an interface between the steel cord and the rubber, wherein a molar ratio Cu.sub.2S/CuS of Cu.sub.2S and CuS included in the bonding layer is 1.0 or higher.

This disclosure is to provide a brass-plated steel wire for reinforcing a rubber article, which is capable of improving the initial adhesiveness, heat-resistant adhesiveness and initial adhesion rate. This disclosure is a brass-plated steel wire for reinforcing a rubber article, wherein: when measured with XPS (X-ray photoelectron spectroscopy), an outermost surface contains zinc at an amount of 4.8 atom % or less, phosphorus at an amount of 0.5 atom % or more, and oxygen at an amount of 50 atom % or less; and in the outermost surface, an atomic ratio of copper to zinc is 1 to 6.

This disclosure is to provide a brass-plated steel wire for reinforcing a rubber article, which is capable of improving the initial adhesiveness, heat-resistant adhesiveness and initial adhesion rate. This disclosure is a brass-plated steel wire for reinforcing a rubber article, wherein: when measured with XPS (X-ray photoelectron spectroscopy), an outermost surface contains zinc at an amount of 4.8 atom % or less, phosphorus at an amount of 0.5 atom % or more, and oxygen at an amount of 50 atom % or less; and in the outermost surface, an atomic ratio of copper to zinc is 1 to 6.

A threadlike metallic or metallized reinforcer, for example a thread, film, tape or cord made of carbon steel, at the periphery of which is positioned a layer of metal referred to as surface metal chosen from copper, nickel and copper/nickel alloys, is characterized in that this surface metal layer is itself coated, at least in part, with at least one layer of graphene; preferably, there is grafted, to this graphene, at least one functional group which can crosslink to a polymer matrix. This reinforcer of the invention is effectively protected from corrosion by virtue of the graphene present at the surface; advantageously, it can be adhesively bonded directly, without adhesion primer or addition of metal salt, to an unsaturated rubber matrix, such as natural rubber, by virtue of the possible functionalization of this graphene.

A threadlike metallic or metallized reinforcer, for example a thread, film, tape or cord made of carbon steel, at the periphery of which is positioned a layer of metal referred to as surface metal chosen from copper, nickel and copper/nickel alloys, is characterized in that this surface metal layer is itself coated, at least in part, with at least one layer of graphene; preferably, there is grafted, to this graphene, at least one functional group which can crosslink to a polymer matrix. This reinforcer of the invention is effectively protected from corrosion by virtue of the graphene present at the surface; advantageously, it can be adhesively bonded directly, without adhesion primer or addition of metal salt, to an unsaturated rubber matrix, such as natural rubber, by virtue of the possible functionalization of this graphene.

Provided are: a rubber article-reinforcing steel cord having excellent corrosion resistance; and a method of producing the same with excellent productivity. In a rubber article-reinforcing steel cord (1), plural sheath strands (3) each formed by twisting together plural steel filaments are twisted together around at least one core strand (2) formed by twisting together plural steel filaments. Brass plating is performed on the steel filaments, and zinc plating is further performed on at least the outer circumference of the brass plating of outermost-layer steel filaments of the sheath strands (3).

Provided are: a rubber article-reinforcing steel cord having excellent corrosion resistance; and a method of producing the same with excellent productivity. In a rubber article-reinforcing steel cord (1), plural sheath strands (3) each formed by twisting together plural steel filaments are twisted together around at least one core strand (2) formed by twisting together plural steel filaments. Brass plating is performed on the steel filaments, and zinc plating is further performed on at least the outer circumference of the brass plating of outermost-layer steel filaments of the sheath strands (3).