| 摘要 |
1298194 Microcapsules AGFA-GEVAERT NV 18 Nov 1969 [20 Nov 1968 31 Dec 1968] 55080/68 Addition to 1048696 Heading B8C A modified process for preparing microcapsules having an aqueous core according to the main patent comprises emulsifying an aqueous core material containing dissolved material in a solution of a film-forming polymer in a water-immiscible solvent having a B.P. below 100‹ C., emulsifying that emulsion in an aqueous dispersion of a hydrophilic colloid containing the same dissolved material as the aqueous core material at the same or at a higher concentration, and removing the water-immiscible solvent by evaporation (the modification being the addition of dissolved material to the hydrophilic colloid solution). Specific examples relate to the encapsulation of aqueous solutions of potassium hexacyanoferrate (III); N-(2- hydroxyethyl) - 2,3,3 - trimethyl - indolinium bromide; hydroquinone and lead acetate, each solution also containing dissolved gelatine and glycerol or ethylene glycol. |
