Aqueous inks comprising capsules stabilised by cationic dispersing groups

An aqueous ink comprising,

• capsules comprising a polymeric shell surrounding a core, the core comprises one or more chemical reactants capable of forming a reaction product upon application of heat and/or radiation,
• wherein, each capsule is obtainable by:
• dispersing under high shear a non-aqueous solution in an aqueous solution and adding a polyamine compound having at least three nucleophilic groups to the dispersion,
• wherein the non-aqueous solution comprises i) a compound selected from the group consisting of di- or poly-acid chlorides, di- or oligoisocyanates, di- or oligosulfochlorides, di- or oligo-chloroformates, an isocyanate monomer, and mixtures thereof;
• ii) one or more chemical reactants capable of forming a reaction product upon application of heat and/or radiation;
• and iii) a water-immiscible solvent having a boiling point below 100° C. at normal pressure,
• wherein the aqueous solution comprises a surfactant comprising a quaternary ammonium group and at least one primary or secondary amine to covalently bond the surfactant to the polymeric shell;
• and
• a colorant stabilized by cationic dispersing groups.