METHOD FOR COATING PARTICLES OR LIQUID DROPLETS

摘要

Solid particles or viscous liquid droplets of core material (27) are encapsulated in a coating material (21) largely as single particles with a single coherent coating, by feeding a suspension of the two materials onto a rotating surface (13). The suspension is centrifugally dispersed by the rotating surface into relative large coated particles (27, 27a) and relatively small droplets (21a) of coating material. Only the size of the droplets of unused coating corresponds to the droplet formed from atomization of the liquid coating material. The size of the coated particles depends on the size of the uncoated particles and is much less dependent upon the atomization characteristics of the rotating surface. Upon being thrown from the rotating surface, or falling from that surface, the droplets (21a) and coated particles (27, 27a) are solidified by exposure to air and are separated by sieving, or the like. The solidified droplets of pure coating material may be recycled into the suspension. Coating of all particles is achieved by dispersing the individual components of core material in the coating material before the resulting suspension reaches the rotating surface.