Catalyst for polyester polycondensation reaction

A bio-based colorless polyester resin (cPR) composition consisting of at least one polyacid, and a polyol, wherein said colorless polyester is generated from the reaction of a rosin acid and a bis-epoxy monomer to form a rosin diol and subsequently reacting said rosin diol with at least one polyacid and a polyol, wherein said reacting is accomplished in the presence of a phosphinic acid catalyst selected in an amount of from about 0.005 weight percent to about 0.02 weight percent of the total reactants and a titanium catalyst, wherein the ratio in parts by weight of the titanium-based catalyst to the phosphinic acid catalyst is from about 2:1 to about 5:1 and wherein said cPR has a Gardner Color Scale value of from about 1 to about 5.

A process for the preparation of a toner composition consisting of mixing a colorant and a colorless polyester resin, wherein said colorless polyester is generated from the reaction of a rosin acid and a bis-epoxy monomer to form a rosin diol and subsequently reacting said rosin diol with a polyacid and a polyol, and optionally, a multifunctional branching agent, wherein said reacting is accomplished in the presence of a phosphinic acid catalyst selected in an amount no more than about 0.04 weight percent, no more than about 0.03 weight percent, no more than about 0.02 weight percent, no more than about 0.01 weight percent, no more than about 0.008 weight percent, or no more than about 0.005 weight percent of the total reactants, and a titanium catalyst, and wherein the ratio in parts by weight of the titanium catalyst to the phosphinic acid is from about 2:1 to about 5:1, from about 2.5:1 to about 4.5:1, or from about 3:1 to about 4:1.