THREAD RUBBER FOR GOLF BALL

摘要

PROBLEM TO BE SOLVED: To improve aging resistance and repulsive property by forming thread rubber in such a manner that the holding rate of tensile strength after aging by specific conditions, the hysteresis loss at the time of constant stress elongation and elongation exhibit specific values. SOLUTION: The thread rubber which is >=70% in the holding rate of the tensile strength after aging for 7 days at 70 deg.C, is <=50% in the hystersis loss at the time of the constant stress elongation of 100kg/cm<2> and is 900 to 1400% in the elongation at the time of the constant stress elongation of 100kg/cm<2> is used as the thread rubber to be used for the thread-rubber winding golf ball. More preferably, the thread rubber formed by vulcanizing a rubber compsn. contg. the base material rubber consisting of high cis-polyisoprene rubber and low cis-polyisoprene rubber, 0.1 to 1.0 pts.wt. zinc oxide per 100 pts.wt. base material rubber and a phenolic compd. as an antioxidant is used as the thread rubber. The base material rubber consisting of the high cis-polyisoprene rubber is otherwise used.