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.

Abstract: Synthetic resins suitable for use in printing ink compositions are produced by reacting a mixture consisting essentially of (a) a predominant amount of dicyclopentadiene and lesser amounts of (b) at least one hydrocarbon selected from the group consisting of monoolefins, diolefins, and polyenes each having more than five carbon atoms, and having no aromatic rings, and (c) at least one member selected from the group consisting of fatty acid-containing materials and rosin acid-containing materials. Additional synthetic resins suitable for use in printing ink compositions are produced by reacting components (a) to (c) above with an ethylenically unsaturated lower aliphatic dicarboxylic acid or anhydride, such as maleic anhydride.