A steel cord with a construction of m+n having a first group of core filaments having a number of m and a second group of sheath filaments having a number of n, the second group and the first group are twisted around each other with the same twist pitch and same twist direction, wherein the core filaments are not twisted with each other, the core filaments are parallel or have a twist pitch being more than 300 mm, and the sheath filaments have a twist pitch being less than or equal to 30mm, the core filaments have an average tensile strength Tc in MPa when being un-ravelled from said steel cord, the sheath filaments have an average tensile strength Ts in MPa when being un-ravelled from said steel cord, Tc and Ts satisfy: 5<(Tc-Ts)<200. The steel cord has high breaking load and high production efficiency without cost increase.

The invention provides a steel cord for rubber reinforcement. The steel cord comprises a core strand and at least three outer strands twisted around the core strand, the core strand comprises at least one first core filament and multiple first outer filaments twisted around the first core filament, each outer strand comprises a number of second filaments, at least one of multiple first outer filaments is preformed prior to being twisted into the core strand, and at least one of second steel filaments is straight prior to being twisted to form each outer strand. The steel cord has improved performance on core filament migration.

The present invention is directed to an article of manufacture, in one case a pneumatic tire. having at least one cord-reinforced rubber component comprising (A) a reinforcing cord; and (B) a rubber composition contacting the cord, the rubber composition comprising (1) from 70 to 100 phr of at least one polyisoprene rubber selected from the group consisting of natural rubber or synthetic polyisoprene; (2) from 0 to 30 phr of at least one additional rubber selected from the group consisting of polybutadiene and styrene-butadiene rubber; (3) from 20 to 80 phr of carbon black; (4) from 2 to 10 phr of silica; (5) from 0 to 1 phr of a cobalt salt; and (6) from 0.5 to 5 phr of N, N′-m-phenylene bismaleimide; wherein the rubber composition excludes resins and silane coupling agents.

A tire for a civil engineering vehicle the endurance of which has been improved by the addition of an anti-creep layer (30) with a thickness E2 interposed between the airtight inner layer (20), with a thickness E1, and the reinforcer coating layer (46) of the carcass reinforcement (40), with a thickness E3. The thicknesses E1, E2 and E3, being measured in millimetres in a shoulder region forming the transition between the crown and each sidewall of the tire, satisfy the following equations: 2≤E1≤4; 6≤E2+E3 and E1/E2≥0.6. In addition, the viscoelastic loss P60 of the elastomeric mixture M2 of the anti-creep layer (30) is at most equal to 20%.

The invention relates to a rubber composition based on at least one functionalized elastomer comprising polar functional groups, a reinforcing filler and a specific polyphenolic compound.

A tire comprises at least first and second working plies (16, 18) respectively comprising first and second reinforcing elements (50, 52) in which at least one of the following relationships is satisfied:
−4053×E1+4720≤(D1.sup.4×d1×1000)/E1  (I)
−4053×E2+4720≤(D2.sup.4×d2×1000)/E2  (II)
where D1, D2 are the diameter of each reinforcing element (50, 52) made up of a metallic monofilament (66, 68), and D1 and/or D2 ranges from 0.34 to 0.38 mm, d1, d2 are the density of the reinforcing elements (50, 52), expressed in monofilaments per decimetre, and E1, E2 are the mean thickness of the working ply (16, 18), expressed in mm.

Provided is a rubber composition for coating a metal cord that can achieve both crack resistance and low heat generation properties at a high level. The rubber composition for coating a metal cord contains a rubber component, carbon black having an adsorption specific surface area of cetyltrimethylammonium bromide (CTAB) of 110 m.sup.2/g to 160 m.sup.2/g, a half width ΔD50 of a peak including a Stokes equivalent diameter Dst that is the most frequent in an aggregate distribution obtained with a centrifugal sedimentation method of 60 nm or less, and a ratio of the ΔD50 to the Dst (ΔD50/Dst) of 0.95 or less, silica having a CTAB adsorption specific surface area of 200 m.sup.2/g or more, and a vulcanizing agent.

The carcass of the pneumatic tire includes a plurality of carcass cords formed of conductors and arranged along the tire radial direction and the tire width direction, and a circumferential cord formed of conductors and arranged along the tire circumferential direction. The circumferential cord contacts the carcass cord.

A pneumatic radial tire includes a carcass structure having a pair of sidewalls and a crown, a pair of beads, a tread, a belt structure, and a plurality of reinforcing hoops. The plurality of spaced apart reinforcing hoops are disposed intermediate the crown of the carcass structure and the tread, and are formed of a rigid material coated in an elastomeric material. The plurality of reinforcing hoops includes a pair of outer reinforcing hoops disposed adjacent the sidewalls of the carcass, and an at least one inner reinforcing hoop disposed between the outer reinforcing hoops.

A tire includes a pair of beads and a crown region including a circumferential tread disposed radially above a circumferential belt. The tire further includes a pair sidewalls extending from the pair of beads to the crown region. A body ply wraps around the pair of beads and terminates in a pair of turn up ends in the crown region, below the middle 30% of the circumferential belt. A conductive substance is disposed along a strip of the body ply.