Abstract: A polymeric dispersion in aqueous phase for use as a polymeric binder for paper and other nonwoven articles is described utilizing a polyisocyanate in combination with said polymeric binder to increase the ratio wet tensile/dry tensile strength. The polyisocyanate seems to be functioning by increasing the fiber to binder interaction rather than by simply increasing the strength/crosslink density of the binder. The polyisocyanate can be blocked isocyanate(s) or water dispersible isocyanate(s). The binder may or may not have isocyanate reactive species along the backbone.