| 摘要 |
PROBLEM TO BE SOLVED: To provide natural rubber having improved Po (Wallace plasticity degree) and plasticity degree residual ratio, PRI than conventional technique for meet needs for maintaining PRI high without depending seasons and to overcome problem that PRI of natural rubber varies depending on seasons which the natural rubber is collected due to characteristics that the a raw material is a natural product, where PRI represents a ratio of plasticity after aging to before aging when the natural rubber is applied to air heating aging, i.e. higher PRI means higher aging resistance, and further to prevent change of viscosity over time. ! SOLUTION: Above problem is solved by natural rubber obtained by cutting a coagulum of natural rubber latex and contacting the cut product and citric acid and/or a solution thereof. Further viscosity change can be reduced by adding semicarbazide and a salt thereof and/or a solution thereof. ! COPYRIGHT: (C)2015,JPO&INPIT |
