Wiggins Teape Limited

Thomas A McGhee

David J Hasler

A method of encapsulating finely divided particulate material, such as minute droplets of a water-immiscible liquid, to produce microcapsules in which the particulate material is surrounded by polymeric shells, comprising the steps of forming a dispersion of the particulate material in an aqueous medium containing a water-soluble ureaformaldehyde precondensate, a water-soluble melamineformaldehyde precondensate and a water-soluble polymer which is capable of being cross-linked by said precondensates, and condensing said precondensates by acid catalysis with resultant cross-linking of the polymer about the particulate material so as to form the polymeric shells. The polymer may be a cellulose derivative, starch, a starch derivative, a polyacid, a polyester, a polyanhydride copolymer, a polyacrylamide or a polyacrylamide copolymer, and is preferably an acrylamide/acrylic acid copolymer.

Growing community of inventors

St. Albans, United Kingdom

Thomas A McGhee