Rosin modified phenolic resin, gel varnish, printing ink, and method for producing rosin modified phenolic resin

摘要

The present invention provides a rosin modified phenolic resin obtained by reacting a rosin, a phenol-formaldehyde initial condensate and a polyhydric alcohol, wherein the phenol-formaldehyde initial condensate is obtained by reacting phenols with formaldehyde in an ester of an animal and vegetable oil fatty acid and a monoalcohol and the proportion of the ester is from 5 to 200% by weight based on the total amount of the phenols and formaldehyde charged, a gel varnish and a printing ink, which contain the same, and a method for producing a rosin modified phenolic resin.