RESIN COMPOSITION CONTAINING AMPHOTERIC ION GROUP, AND WATER-BASE INK

摘要

PROBLEM TO BE SOLVED: To obtain a resin composition which is excellent in water solubility and film-forming properties and gives a coating film little in stickiness by reacting a free-radical polymerization product having cationizable amino groups with a halogenated carboxylic acid compound in the presence of a base to form amphoteric ion groups. SOLUTION: A free-radical polymerization product having cationizable amino groups [e.g. poly(N,N-dimethylaminopropylacrylamide) obtained by polymerizing N,N-dimethylaminopropylacrylamide in the presence of azobisisobutyronitrile] is reacted with a halogenated carboxylic acid compound represented by formula I and/or formula II in the presence of a base to form amphoteric ion groups represented by formula III and/or formula IV. In the formulas, n is 2 or more but preferably 20 or less; m is 1 or more but preferably 20 or less; and X is a halogen. The water-base ink containing this composition is excellent in gloss and fixability.