A belt for use as for example an elevator belt, flat belt, synchronous belt or toothed belt comprises steel strands held in parallel by a polymer jacket. The steel strands have a diameter ‘D’ and are separated by a pitch ‘p’. The ratio of diameter ‘D’ over pitch ‘p’ is larger than 0.55. Such belt arrangement prevents the cutting of the polymer jacket between strand and pulley and abates the noise generation during use. The belts are best built with a type of parallel lay strands particularly designed for use in a belt. These strands do not show core migration during use of the belt.

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 reinforcement strand (400) comprises a core (403) around which steel filaments (404) are twisted all with the same final lay length and direction. The steel filaments are arranged in an intermediate layer comprising N first steel filaments and an outer layer of 2N steel filaments circumferentially arranged around the intermediate layer. In the intermediate layer filaments will contact one another at a closing lay length that is determined by the number of steel filaments N in the intermediate layer, the diameter of the core and the diameter of the first steel filaments. By choosing the final lay length and direction equal to the between two and six times the closing lay length gaps will form between the intermediate layer filaments. The 2N outer layer filaments are further divided into a group of smaller (408) and a group of larger (406) diameter steel filaments.

A method of manufacturing an escalator handrail which has a composite material including a metallic steel wire and a thermoplastic resin, said metallic steel wire having a center elemental wire and a plurality of strands placed so as to surround the center elemental wire, including: a preheating step of heating the metallic steel wire; a composite-material forming step of integrating the metallic steel wire heated in the preheating step with the thermoplastic resin in a molten state to thereby form the composite material; and a cooling step of cooling the composite material formed in the composite-material forming step.

Rubber article-reinforcing steel cord in which corrosion resistance is improved without an increase in weight. 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. Core strand (2) and sheath strands (3) are each formed by twisting together one or two core filaments (2c) and (3c) and plural sheath filaments (2s) and (3s), respectively, and a relationship represented by the following Formula (1) is satisfied when a wire diameter of core filament(s) (2c) of core strand (2), a wire diameter of sheath filaments (2s), a wire diameter of core filaments (3c) of sheath strands (3), and a wire diameter of sheath filaments (3s) are defined as dcc, dcs, dsc and dss, respectively: dcc>dcs≥dsc>dss (1).

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95≤MC≤175, where MC=(J×MI+L×ME)/(J+L); MI=200×cos.sup.4(α)×[Q×(D1/2).sup.2×cos.sup.4(β)+P×(D2/2).sup.2×cos.sup.4(δ)+N×(D3/2).sup.2×cos.sup.4(γ)]/[Q×(D1/2).sup.2+P×(D2/2).sup.2+N×(D3/2).sup.2]; and ME=200×cos.sup.4(α′)×[Q′×(D1′/2).sup.2×cos.sup.4(β′)+N′×(D2′/2).sup.2×cos.sup.4(γ′)]/[Q′×(D1′/2).sup.2+N′×(D2′/2).sup.2], where D1, D1′, D2, D2′, and D3 are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), δ is the helix angle of each intermediate thread (F2) and γ and γ′ are the helix angle of each external thread (F3, F2′).

A steel cord containing a core layer and an sheath layer, the core layer containing a plurality of core wires with a number of n and the sheath layer comprises a plurality of sheath wires with a number of m, and the steel cord has a flat cross-section with a major axis and a minor axis, the flat cross-section has a flat ratio being the ratio of the length of the major axis and the length of the minor axis, the flat ratio is more than 1.2, the steel cord has a breaking load being BL.sub.cord, the core wires and the sheath wires have a sum breaking load being Sum BL.sub.wires when the core wires and the sheath wires are un-twisted from the steel cord, BL.sub.cord and Sum BL.sub.wires satisfies the following formula: BL.sub.cord/Sum BL.sub.wires>96%. The steel cord has higher breaking load.

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95≤MC≤180, where MC=(J×MI+L×ME)/(J+L); MI=200×cos.sup.4(α)×[Q×(D1/2).sup.2×cos.sup.4(β)+P×(D2/2).sup.2×cos.sup.4(δ)+N×(D3/2).sup.2×cos.sup.4(γ)]/[Q×(D1/2).sup.2+P×(D2/2).sup.2+N×(D3/2).sup.2]; and ME=200×cos.sup.4(α′)×[Q′×(D1′/2).sup.2×cos.sup.4(β′)+P′×(D2′/2).sup.2×cos.sup.4(δ′)+N′×(D3′/2).sup.2×cos.sup.4(γ′)]/[Q′×(D1′/2).sup.2+P′×(D2/2).sup.2+N′×(D3′/2).sup.2], where D1, D1′, D2, D2′, D3 and D3′ are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), δ and δ′ are the helix angle of each intermediate thread (F2, F2′) and γ and γ′ are the helix angle of each external thread (F3, F3′).

The invention relates to a multi-strand cord (50) comprising an internal layer (CI) of the cord made up of K=1 three-layer (C1, C2, C3) internal strand (TI), with the internal layer (C1) being made up of Q internal metallic threads (F1), the intermediate layer (C2) being made up of M intermediate metallic threads (F2) and the external layer (C3) being made up of N external metallic threads (F3), and an external layer (CE) of the cord made up of L>1 three-layer (C1′, C2′, C3′) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C1′) being made up of Q′ internal metallic threads (F1′), the intermediate layer (C2′) being made up of M′ intermediate metallic threads (F2′) and the external layer (C3′) being made up of N′ external metallic threads (F3′).

The cord (50) has: an endurance criterion SL≤40 000 MPa.Math.mm with

[00001]$SL=\max \left(\frac{\Delta {\sigma }_{\mathrm{bending}\_\mathrm{CI}}}{\mathrm{Cp}};\frac{\Delta {\sigma }_{\mathrm{bending}\_\mathrm{CE}}}{C_r\times \mathrm{Cp}}\right);$  and a size criterion Ec≥0.46 with Ec=Sc/Se.

A reinforcement strand (400) comprises a core (403) around which steel filaments (404) are twisted all with the same final lay length and direction. The steel filaments are arranged in an intermediate layer comprising N first steel filaments and an outer layer of 2N steel filaments circumferentially arranged around the intermediate layer. In the intermediate layer filaments will contact one another at a closing lay length that is determined by the number of steel filaments N in the intermediate layer, the diameter of the core and the diameter of the first steel filaments. By choosing the final lay length and direction equal to the between two and six times the closing lay length gaps will form between the intermediate layer filaments. The 2N outer layer filaments are further divided into a group of smaller (408) and a group of larger (406) diameter steel filaments.