It is a Sulphur donor and sometimes a vulcanising agent for Semi & EV cure system. These organic compounds contain sulfur in a thermally changed form. Under normal curing conditions, free sulfur is released which, in contrast to normal sulfur, mainly forms mono-sulfidic and di-sulfidic bridges. Because of their higher bond energies, these di-sulfidic bridges are much more resistant to reversion and are responsible for the excellent heat-aging resistance of the vulcanizates. Replacing sulfur with sulfur donors results in less free sulfur in the rubber compound formulation and this leads to advantages such as improved physical properties, lower compression set, excellent reversion resistance, vulcanizates with improved ageing resistance, no sulfur blooming, no contact staining with heavy metals, higher processing safety(scorch).