Cutback asphalts are often used for priming as they are able to penetrate through dust layer adhering to the base course, and also penetrate through small pores so as to enhance cohesion between aggregates. The use of cutbacks has several drawbacks. Cutback asphalts contain excessive amount of hydrocarbon solvent (approximately 35-40%) resulting in slow curing (i.e. at least one week before paving the base course) but the main problem is that the evaporation of high amount of hydrocarbon solvent leads to environmental pollution by volatile organic compounds (COV). In addition, it is hazardous for the workers since the cutback asphalt is a flammable material which could catch fire and there have been several accidents during storage and use of cutback. Many countries have banned the use of cutback asphalts for these reasons. Moreover, use of solvent in the cutbacks adds to the total cost owing to high amount of hydrocarbon solvent used.