Abstract: Synthetic resins suitable for use in printing ink compositions are described comprising (a) a predominant amount of dicyclopentadiene and lesser amounts of (b) at least one member selected from the group consisting of dimerized aliphatic, cyclic, and non-cyclic dienes of five carbon atoms; debutanized aromatic concentrates; C-5 olefins; acyclic conjugated C-5 dienes; mono-olefins, diolefins and polyenes each having more than five carbon atoms and having no aromatic rings, (c) at least one member selected from the group consisting of tall oil; fatty acid-containing materials and rosin acid-containing materials, (d) at least one ethylenically unsaturated lower aliphatic dicarboxylic acid or anhydride, and (e) at least one member selected from the group consisting of materials containing two or more reactive groups, at least one of which must be a hydroxyl group.