Process of producing microcapsules
Abstract
Abstract PRESSURE-RUPTURABLE MICROCAPSULES HAVING OUTER WALLS OF WAX WHICH ENCASE DROPLETS OF ANY OILY MATERIAL ARE PRODUCED IN THE ABSENCE OF COACERVATION FORCES BY EMULSIFYING AN OIL-IN-WATER-TYPE OF EMULSION INTO MELTED WAX, TO FORM A WATER-IN-OIL TYPE OF EMULSION, THE DISPERSING THE WAX EMULSION TO FORM MICRO-DROPLETS THEREOF IN AN AQUEOUS PHASE, AND COOLING THE RESULTING DISPERSION TO SOLIDIFY THE WAX. A MEMBRANE OF HYDROPHILIC COLLOID MATERIAL IMPERMEABLE TO THE ENCAPSULATED OIL IS FORMED BETWEEN THE OIL AND THE WAX AND ACTS AS A PROTECTIVE COLLOID. THE DISPERSION OF MICROCAPSULES CAN BE COATED ONTO AN APPROPRIATE BASE SHEET OR THE MICROCAPSULES CAN BE RECOVERED BY SPRAY DRYING OR BY FILTERING AND DRYING.
Inventors
- 👤 Karl G Gragger
Bibliographic Details
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