Abstract: A fiber cord for reinforcing rubber includes an organic fiber covered with a resin for which the average integration value of hardness measured by AFM is 150 MPa or less. A fiber cord for reinforcing rubber which could not be achieved with prior art, can be achieved with improved initial adhesiveness and heat-resistant adhesiveness as well as excellent stress relaxation for the rubber-cord composite.

Abstract: A polyester fiber cord for reinforcing rubber including a polyester fiber preloaded with a polyepoxide compound; and an adhesive applied to the polyester fiber and including a resorcinol-formalin-rubber latex (A), a blocked polyisocyanate compound (B), and a halogenated phenol derivative (C), wherein a rubber latex, a material of the resorcinol-formalin-rubber latex (A) in the adhesive, contains a mixture of a chloroprene rubber latex (D) and a polybutadiene rubber latex (E) in an amount of 80 to 100 parts by mass based on 100 parts by mass of the total solids of the rubber latex, and a mixing ratio of the chloroprene rubber latex (D) to the polybutadiene rubber latex (E) ((D)/(E)) is 80/20 to 20/80 (solid content mass ratio).