EMULSION USEFUL IN PREPARING RADIATION SENSITIVE MICROCAPSULES, PREPARATIONS OF MICROCAPSULES AND PROCESSES FOR FORMING THE SAME, AND IMAGING SHEETS

摘要

An oil-in-water emulsion which is useful in preparing radiation sensitive microcapsules includes a radiation sensitive composition in the oil phase and methylated polygalacturonic acid in the aqueous phase. Microcapsules are prepared by forming discrete capsule walls about the droplets of radiation sensitive material in such emulsion. Prepared microcapsules are further characterised in having an average particle size of about 4 to 8 microns, not less than 90% of the capsules having a particle size less than 10 microns. An imaging sheet comprises a support carrying on one surface thereof a layer of such microcapsules.