C5/C9, Aliphatic/Aromatic Resins are C5 tackifiers co-polymerized with aromatic monomers. They are excellent tackifiers for use in EVA, SBS, and natural rubber polymers. They can also be used in SIS-based HMPSA to provide low melt viscosity with an optimum balance between cohesion and adhesion. Sometimes the slightly aromatic modified C5 resins are used in APO to provide limited compatibility resulting in shorter open times. Darker colored, lower cost types are often used in packaging HMA based on EVA. These resins are mostly C9-based co-polymerized with C5 aliphatic monomers.