| abstract |
Microcapsules are prepared by polycondensation of a melamine/formaldehyde resin mixture in water, in which essentially water-insoluble material forming the capsule core is dispersed, in the presence of an anionic protective colloid, by a process wherein the melamine/formaldehyde resin mixture is composed of:a) an aqueous solution of a condensate ofa1) 1 mol of melamine,a2) from 2 to 5 mol of formaldehyde anda3) from 0 to 0.5 mol of a melamine derivative which can undergo an addition or condensation reaction with formaldehyde anda4) from 1 to 5 mol of a C1-C3-alkanol andb) from 0.01 to 1 mol of a water-soluble primary, secondary or tertiary amine or ammonia. |