| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve depression effect against fold back end separation by high elasticity while maintaining rupture resistance of hard stiffener rubber. SOLUTION: A rubber composite in which over 60 weight part of carbon black of nitrogen adsorption specific surface area of 130m<2> /g or less, and 5-30 weight part of polyethlene of melting point 120 deg.C or above and melt flow rate 20 or less are combined with 100 weight part of rubber content containing natural rubber over 75 weight percent, is applied to the stiffener rubber.</p> |
