| abstract |
The invention addresses the problem of providing a binder for inkjet printing ink and inkjet printing ink containing said binder that are capable of forming printed images of extremely good durability in terms of rubfastness, alkali resistance and the like without loss of favorable ink discharge stability, storage stability, etc. The invention relates to a binder for inkjet printing ink and printed matter characterized in that a polyurethane (C), which has a structure on the side chains that is derived from a vinyl polymer (a1) with two hydroxyl groups on one end, is dispersed in an aqueous medium (D). The polyurethane is obtained by reacting a polyol (A), which contains the vinyl polymer (a1) and one or more kinds of polyols (a2) selected from the group consisting of polyether polyol, polyester polyol, polyester ether polyol and polycarbonate polyol, with a polyisocyanate (B). |