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

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

• one or a plurality of the reinforcing cords are aligned in parallel and covered with rubber,
• the reinforcing cord includes a nonmetallic fiber,
• where the modulus per cord of the reinforcing cord is A (GPa), the number of cord end counts per 50 mm width of the rubber-cord composite is B (/50 mm), the thickness of the reinforcing cord is C (mm), the specific gravity of the reinforcing cord is D (g/cm3), the number of upper twists of the reinforcing cord is E (times/10 cm), and the total fineness of the reinforcing cord is F (dtex),
• the modulus X per 50 mm width of the rubber-cord composite represented by X=A×B is 1,000 GPa or more,
• a cord interval Y between the adjacent reinforcing cords in the rubber-cord composite in a direction perpendicular to the cord longitudinal direction represented by Y=(50−B×C)/B is from 0.1 mm to 5 mm, and
• the twist coefficient Z of the reinforcing cord represented by Z=tan θ=E×√(0.125×F/D)/1,000 is 0.3 or less.