MC GRADES Cutback Bitumen is simply a combination of asphalt cement and petroleum solvent. We use Like emulsions or cutbacks because they reduce asphalt viscosity for lower temperature uses (tack coats, fog seals, slurry seals and stabilization material). Similar to emulsified asphalts, after cutback asphalt is applied the petroleum solvent evaporates leaving behind asphalt cement residue on the surface to which it was applied, so we say to cutback asphalt “cure” as the petroleum solvent evaporates away. The use of cutback asphalts is decreasing because of:
•Environmental regulations. Cutback asphalts contain volatile chemicals that evaporate into the atmosphere. Emulsified asphalts evaporate water into the atmosphere.
•Loss of high energy products.