Method for producing microcapsules and photosensitive microcapsules produced thereby
AssigneeThe Mead Corporation
InventorCharles P. Marabella
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Abstract
A method for forming microcapsules by enwrapping an oily core material in a formaldehyde condensation product formed in situ wherein methylated polygalacturonic acid is used as an emulsion stabilizer; the method is particularly useful in forming photosensitive microcapsules in that uniform small microcapsule size is obtained.
Claims22
A process for forming microcapsules having discrete capsule walls comprising the steps of forming an emulsion of an oily core material in a continuous aqueous phase containing methylated polygalacturonic acid as an emulsion stabilizer, and enwrapping particles of said oily core material in a formaldehyde condensation product produced by in situ condensation of an amine and formaldehyde.
An imaging sheet comprising a support carrying on one surface thereof a layer of microcapsules having discrete capsule walls, said microcapsules containing a radiation sensitive material in the internal phase and being formed by enwrapping particles of an oil-in-water emulsion containing methylated polygalacturonic acid as an emulsion stabilizer in a formaldehyde condensation product produced by in situ polymerization of formaldehyde and an amine, and said capsules being further characterized by an average particle size of about 4 to 8 microns and not less than 90% of said capsules having a particle size less than 10 microns.
Dependencies are inferred from the claim text.