Process for the production of microcapsules

摘要

Microcapsules with a melamine-formaldehyde or urea-formaldehyde resin capsule shell are produced by adding in advance a polyvalent isocyanate, a polyvalent isothiocyanate or a prepolymer thereof to the hydrophobic oily liquid to be encapsulated, emulsifying the hydrophobic oily liquid in an aqueous solution of a water-soluble polymer, adding an aqueous solution of melamine and formaldehyde or a precondensate thereof or urea and formaldehyde to the emulsion, and polymerizing the melamine and formaldehyde or a precondensate thereof or the urea and formaldehyde.