| abstract |
A radiation curable resin which is a polyurethane acrylate having (meth)acryloyloxy groups at the terminal end of the molecule and in the molecular chain thereof, and containing metal sulfonate groups in the molecule in a ratio of 3.0 to 1,500 equivalent/10⁶ g of the resin, obtainable by reaction ofn (1) a copolyester having hydroxyl groups at both terminal ends of the molecule and containing metal sulfonate groups therein, (2) a diisocyanate, (3) a compound (A) having at least one (meth)acryloyloxy group and two hydroxyl groups, (4) a compound (B) having at least one (meth)acryloyloxy group and one hydroxyl group, and optionally (5) a polyol other than the above (1) or (3). the radiation curable resin containing a compound (C) having at least one carboxylic acid group and two hydroxyl groups in addition to the above components (1) to (5) is also disclosed. |