INSPECTION METHOD OF RUBBER MATERIAL

PROBLEM TO BE SOLVED: To provide an inspection method of rubber material, capable of quickly and easily evaluating a cross-linked state in rubber (a state of deterioration).SOLUTION: An inspection method of rubber material using a pulsed nuclear magnetic resonance (P-NMR) apparatus, includes the steps of: measuring a spin-spin relaxation time Tof rubber by a Carr-Purcell-Meiboom-Gill (CPMG) method; dividing an obtained Trelaxation curve (a free induction decay curve) into a Tcomponent having a short relaxation time and a Tcomponent having a long relaxation time by a formula (1); and estimating a breaking elongation Eb from a value of the Tcomponent and a hardness Hd from a value of the Tcomponent. (where Tis a relaxation time of the component having the short relaxation time; Tis a relaxation time of the component having the long relaxation time; Ais strength at t=0 of the component having the short relaxation time; Ais strength at t=0 of the component having the long relaxation time; and t is an observation time.)