Rubber-cord composite, reinforcing member for tires, and tire using same

A rubber-cord composite to be used for a spiral cord layer in a tire reinforcing member having at least one core-material cord layer and the spiral cord layer comprising a reinforcing cord spirally wound on the core-material cord layer, said rubber-cord composite comprising:

• the reinforcing cord is singly or plurally arranged in parallel and coated with a rubber,
• the reinforcing cord comprises a nonmetallic fiber, and
• where the modulus per the reinforcing cord is A (GPa), the cord end counts of the rubber-cord composite per 50 mm width is B (cords/50 mm), the thickness of the reinforcing cord is C (mm), the specific gravity of the reinforcing cord is D (g/cm3), the final twist number of the reinforcing cord is E (times/10 cm), and the total fineness of the reinforcing cord is F (dtex):
• a modulus X of the rubber-cord composite per 50 mm width represented by X=A×B is 1,000 GPa or higher;
• a cord interval Y in a direction perpendicular to the cord longitudinal direction between adjacent reinforcing cords in the rubber-cord composite represented by Y=(50−B×C)/B is 0.1 mm to 5 mm;
• and
• a twisting coefficient Z of the reinforcing cord is represented by Z=tan θ=E×√(0.125×F/D)/1,000 is higher than 0.3.