Continuous microencapsulation

Claim 1

A process for continuously manufacturing minute capsules in a closed capsule manufacturing conduit comprising the steps of: (a) introducing (i) system modifier material selected from the group consisting of poly(ethylene-co-maleic anhydride), poly(methylvinylether-co-maleic anhydride), poly(acrylic acid), poly(propylene-co-maleic anhydride), poly(butadiene-co-maleic anhydride) and poly(vinyl acetate-co-maleic anhydride), (ii) intended capsule core material, and (iii) methylol melamine or etherified methylol melamine to form a mixture in an aqueous manufacturing vehicle; (b) conducting said mixture through a continuous emulsification mill; (c) conducting, under non-turbulent flow conditions, the emulsified mixture through a tubular reactor maintained at a temperature of about 40° to 95° C.; and (d) withdrawing the mixture through an exit opening of the conduit after a residence time in the conduit sufficient to yield self-supporting capsule wall material enwrapping the intended capsule cores, said mixture consisting of a dispersion system of capsules in the residual manufacturing liquid.