Process for making dual walled microcapsules
Abstract
Abstract A METHOD OF FORMING DUAL WALLED MICROCAPSULES AROUND CORE PARTICLES OR NUCLEL OF OILY OR SOLVENT MATERIAL IN WHICH THE OILY OR SOLVNET MATERIAL CONTAINING A DIBASIC OR LONG-CHAIN ORGANIC ACID CHLORIDE IS DISPERSED IN AN AQUEOUS SOLSUTION OF A HYDROPHILIC SOLLOIDAL PROTEIN AND A SECOND HYDROPHILIC COLLOID WHICH IS ADAPTED TO UNDERGO COACERVATION WITH THE COLLOIDAL PROTIEN UPON A REDUCTION IN THE PH OF THE AQUEOUS SOLUTION. THE ACID CHLORIDE REACTS WITH THE PROTEIN TO FORM A THIN FILM OF INSOLUBILIZED PROTEIN AROUND THE CORE PARTICLES OR NUCLEI, RELEASING HYDROCHLORIC ACID AS A REACTION BY-PRODUCT WHICH LOWERS THE PH OF THE AQUEOUS SOLUTION TO THE POINT AT WHICH COACERVATION OF THE COLLOIDS TAKE PALCE, DEPOSITING AN OUTER SHELL OF COMPLEX COACERVATE, THE DUAL-WALLED CAPSULES CAN BE GIVEN A HARDENING TREATMENT, USING FORMALDEHYDE OR THE LIKE. THE RESULTANT CAPSULES RETAIN EVEN RELATIVELY VOLATILE MATTER FOR LONG PERIODS OF TIME.
Inventors
- 👤 George Baxter
Bibliographic Details
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