DE2264284

A process for the preparation of a modified hydrocarbon resin suitable for use as a binder in a printing ink from a hydrocarbon resin (I) relatively unsuitable for use as a binder in a printing ink and having a melting point of at most 110 DEG C. which comprises reacting in at least one step in any desired sequence a reactant selected from the group consisting of (I) at least one hydrocarbon resin based on at least one polymerizable hydrocarbon monomer selected from the group consisting of (a) 20 to 100% by weight, referred to the total of polymerizable monomers, of hydrocarbon fractions containing substantial and essential amounts of C5-fractions, (b) 15 to 50% by weight, referred to the total of polymerizable monomers, of methylcyclopentadiene, (Ia) a combination of (I) with an olefinically unsaturated monomer hydrocarbon selected from the group consisting of aromatic hydrocarbons of 8 to 12 carbon atoms, cycloaliphatic hydrocarbons having 5 to 10 carbon atoms and aliphatic hydrocarbons having 2 to 12 carbon atoms, the total amount of monomers always being 100% by weight, with (II) 3 to 20% as much by weight of a dicarboxylic acid unit selected from the group consisting of (IIa) an alpha , beta -olefinically unsaturated dicarboxylic acid and (IIb) an equivalent amount of the corresponding dicarboxylic anhydride as defined in IIa) and with (III) 1 to 100% as much by weight of a phenol aldehyde resin or its equivalent selected from the group consisting of (IIIa) a phenol aldehyde resin and (IIIb) a mixture of a phenol and an aldehyde being the same as the starting material aldehyde of (IIIa); the proportion of (I), (II) and (III) being correlated so that said modified hydrocarbon resin has a melting point of at least 120 DEG C. and a viscosity in 50% toluene solution at 20 DEG C. of at least 100 centipoise, an addition product prepared according said process and a printing ink containing a binder obtained by said process.