Method for producing microcapsules having improved wall characteristics
AssigneeEastman Kodak Company
InventorsIbrahim Katampe, Joseph C. Camillus
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Abstract
A process for forming microcapsules having substantially impermeable microcapsule walls comprising the steps of: forming an emulsion of an internal phase in a continuous aqueous phase, the internal phase including a photosensitive composition and a polyvalent isocyanate, the continuous aqueous phase including a sulfonated polystyrene, at least one of the internal phase or the continuous aqueous phase further including a hydrophilic polymer; and enwrapping particles of the internal phase in an amine-formaldehyde condensation product produced by in situ condensation of an amine and formaldehyde is disclosed.
Claims15
A process for forming microcapsules having substantially impermeable microcapsule walls comprising the steps of:
- forming an emulsion of an internal phase in a continuous aqueous phase, said internal phase including a photosensitive composition and a polyvalent isocyanate, said continuous aqueous phase including a sulfonated polystyrene, at least one of said internal phase or said continuous aqueous phase further including a hydrophilic polymer;
- and
- enwrapping particles of said internal phase in an amine-formaldehyde condensation product produced by in situ condensation of an amine and formaldehyde.
A process for forming photosensitive amine-formaldehyde microcapsules having substantially impermeable walls comprising the steps of:
- emulsifying a photosensitive hydrophobic oil containing a polyvalent isocyanate in a continuous aqueous phase containing a sulfonated polystyrene and a hydrophilic polymer selected from the group consisting of gelatine, gum arabic, starch, cellulose and combinations thereof, wherein said polyvalent isocyanate reacts with water of said aqueous phase to form a substantially impermeable pre-wall around droplets of said hydrophobic oil;
- and
- enwrapping the pre-wall coated droplets of said hydrophobic oil in an amine-formaldehyde condensation product produced by in situ condensation of an amine and formaldehyde.
Dependencies are inferred from the claim text.