PURPOSE: To obtain a cord material having a specific viscoelastic property and useful for the reinforcement of a rubber having high-strength and high fatigue resistance by using a polyhexamethylene adipamide fiber aggregate treated with RFL.
CONSTITUTION: (1) A cord material for the reinforcement of a rubber, consisting of a fiber aggregate and having a fiber weight fraction of ≥95%, a strength of the treating fiber per unit apparent denier of ≥8.5g/d and the following specific viscoelastic properties. Tmax of αa dispersion is ≥125°C Δ(αa)1/2≤78°C, αah≥0.850, Δ(β)1/2≤73°C and βh/αah≥ 0.7. (2) The cord material is produced by drawing a stock fiber aggregate at a draw ratio corresponding to ≤0% of the draw ratio at the drawing point to cause abrupt structural breakage at the spinning stage of the aggregate.
OKAJIMA KUNIHIKO
SHIKAMA YASUHIRO
