PROCESS FOR INTERFACIAL POLYADDITION MICROENCAPSULATION

摘要

Microcapsules, and especially suspensions of microencapsulated colorants well adapted for the manufacture of carbonless papers, are produced by emulsifying a hydrophobic organic fluid which includes an aliphatic diisocyanate and an isocyanurate ring trimer of an aliphatic diisocyanate, and optionally a dissolved organic material, in an essentially aqueous liquid containing a protective colloid, a surfactant, or both, wherein the weight ratio of aliphatic diisocyanate/trimer ranges from 0.05/l to 0.70/l and the surface tension between the aqueous phase and the hydrophobic organic phase ranges from 0 to 20 mN/m, and then forming microcapsules by interfacially reacting a polyamine with the emulsion which results, thereby constituting polyurea walls of said microcapsules by polyaddition.