Abstract: Light colored rosin ester with Gardner color 2-4 was prepared by reacting rosin with alcohol in the presence of a new CLC catalyst.Analysis of the product showed that relative content of dehydroabietic acid and hydrogenated resin acids increased from 0 in rosin to 30% and 22% in rosin ester,respectively,and relative content of abietic type resin acids decreased from 86% to 34%.Contrast experiment without CLC showed that there were no products of dehydroabietic acid and hydrogenated resin acid in rosin ester,and relative content of abietic type resin acid did not change much.It was proved that CLC was a catalyst responsible for the disproportionation reaction of rosin.The decrease of abietic type resin acids through disproportionation was responsible for the color lightening effect on rosin ester.

Key words: light-colored rosin, disproportionated rosin, abietic-type resin acids