Process for producing spherical composite cured melamine resin particles

摘要

A process for producing spherical composite cured melamine resin particles excellent in water resistance, in which colloidal silica is localized near the surface thereof, comprising (a) a step of reacting a melamine compound with an aldehyde compound in an aqueous medium under a basic condition in the presence of a suspension of colloidal silica having an average particle size of 5 to 70 nm to produce an aqueous solution of a precondensate of water-soluble melamine resin; and (b) a step of adding an acid catalyst to the aqueous solution produced in the step (a) to separate out spherical composite cured melamine resin particles.