COMPOSITION FOR OFFSET PRINTING INK BINDER, GEL VARNISH FOR OFFSET PRINTING INK, AND OFFSET PRINTING INK

摘要

PROBLEM TO BE SOLVED: To provide a new rosin-modified phenol resin-based printing ink binder satisfying at the same time, a printing ink flowability and misting resistance.SOLUTION: A composition for offset printing ink binder contains: a rosin-modified phenol resin (1) obtained by the esterification reaction of polyols (B) and a polyaddition material (A) obtained from rosins (a1) which include at least 20 wt.% of dehydroabietic acid and at least 5 wt.% of dihydroabietic acid and/or tetrahydroabietic acid, and a phenol-formaldehyde condensate (a2); and the free resin acids (2) of 2-8 wt.% based on the weight of the component (1).