... yellow powder 3.eco-friendly,slight odor, non--toxic Insoluble sulfur (IS series):1.a new rubber vulcanizing agent2.inflammable yellow ... 3.eco-friendly,slight odor, non--toxic Brief Introduction:Insoluble sulfur is a new rubber vulcanizing agent. It forms IS-series ... vulcanizing agent for rubber. For it can overcome much ordinary sulfur's shortcomings, besides improve the quality of the rubber product ...