Process for the production of microcapsules

Claim 1

A process for the production of microcapsules containing a liquid fill material, comprising the steps of: establishing an aqueous medium which is at an acidic pH and which contains both a melamine formaldehyde precondensate condensable at said acidic pH and a polymer which contains at least one acid, amide, amine, imine, ester, ether, hydroxyl, urethane, thiol or mercaptan group, said melamine formaldehyde precondensate interacting with said polymer in the absence of any substantial amount of urea formaldehyde precondensate to form a species which imparts dispersion-stabilizing properties to the liquid fill material, neither said melamine formaldehyde precondensate nor said polymer alone being dispersion-stabilizing with respect to the liquid fill material at the conditions at which a stable dispersion is to be established; establishing a stable dispersion of liquid fill material in the aqueous medium after formation of said dispersion stabilizing species; and condensing said melamine formaldehyde precondensate by acid catalysis after formation of said dispersion to produce a melamine formaldehyde condensate which separates from solution and enwraps the dispersed liquid fill to produce said microcapsules.