Patent ID: 7228681

Claim:
A steel cord adapted for the reinforcement of elastomers, said steel cord comprising: a core steel filament having a core steel filament diameter d c and being coated with a polymer; six intermediate steel filaments having an intermediate steel filament diameter d i smaller than or equal to said core steel filament diameter d c , said intermediate steel filaments being twisted around said core steel filament; a number of N outer steel filaments having an outer steel filament diameter d o smaller than or equal to said intermediate steel filament diameter d i , said outer steel filaments being twisted around said intermediate steel filaments, said outer steel filaments being preformed in order to allow rubber penetration inside said cord, wherein said number of N is ten or eleven; said core steel filament, said intermediate steel filaments and said outer steel filaments all having a tensile strength of at least 2600 MPa, said cord having an outer diameter D according to the following formula: D ≦d c +2 ×d i +2 ×d o +0.1 mm; wherein all diameters (D, d c , d i , d o ) are expressed in millimeters (mm).