To produce an aqueous resin by the method in which a step for removing solvent is essentially needless, and to provide an ink containing the obtained aqueous resin and useful for being applied to film, paper or the like.
This aqueous resin is obtained by the following three steps: [1] reacting a polyol with an organic polyisocyanate in the absence of solvent to obtain (A) a polyurethane having a number-average molecular weight of ≤30,000; [2] dispersing the polyurethane A in water in the presence of an unsaturated monomer to prepare (B) the aqueous dispersed product of a polyurethane solution; [3] radical-polymerizing the aqueous dispersed product B. The polyurethane obtained in the first step has dissociative groups capable of being ionized.
UNO MINORU
TAKANO MASUMI
OTSUKI TSUKASA
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