ALSAN Coating Asphalt Bleed Blocking Primer is a VOC compliant single component plasticizer free water based acrylic primer/basecoat used to enhance adhesion and block bleed through discoloration from asphalt and asphalt based substrates such as BUR, modified bitumen and asphalt cap sheets. This primer can be used with ALSAN Coating AC 401 or ALSAN Coating SIL 402.