PolyAziridine LLC has developed a new difunctional water-based crosslinker. It is used to crosslink acid or carboxyl functional coatings, inks and adhesives to increase adhesion, physical and chemical properties. Test data, including MEK double rubs and chemical spot testing comparing the new crosslinker and typical trifunctional polyaziridine crosslinkers, showed similar results in clear coatings based on an acid functional polyurethane/acrylic blend and a polyurethane dispersion. This article will also show more properties comparing the new crosslinker to trifunctional polyfunctional aziridine crosslinkers. And, since the new crosslinker is an aqueous dispersion, it has the potential of formulating a one-part system of a polyurethane dispersion ink, adhesive or coating.