An aqueous dispersion of a capsule is composed of a polymeric shell surrounding a core, the core containing an oligomeric blocked isocyanate characterized in that the blocked isocyanate is derived from a di-, tri- or tetrafunctional isocyanate terminated oligomer selected from the group of an isocyanate terminated oligo-ether, an isocyanate terminated oligo-ester, an isocyanate terminated oligo-carbonate, an isocyanate terminated butadiene oligomer, an isocyanate terminated hydrogenated butadiene, an isocyanate terminated isoprene oligomer, an isocyanate terminated silicone and combinations thereof. The dispersion is suitable for pre-treatment liquids and inkjet inks in textile printing.