The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 1981
Filed:
Apr. 17, 1979
Franklin Lim, Richmond, VA (US);
Richard D Moss, Chester, VA (US);
Damon Corporation, Needham Heights, MA (US);
Abstract
Techniques for producing semipermeable microcapsules by interfacial polymerization are disclosed. The material to be encapsulated and a hydrophilic monomer are emulsified within a hydrophobic continuous phase. Polymerization is initiated by dissolving a second monomer in the continuous phase, and occurs only at the interface of the emulsion to result in the formation of macroporous, poorly defined capsule membranes. Next, the affinity of the continuous phase for the hydrophilic monomer is varied by altering the polarity of the continuous phase. This step is accomplished either by isolating and resuspending the raw capsules in a fresh continuous phase of different polar character, or by mixing a second solvent with the continuous phase. By controlling the affinity and the concentration of the second monomer, it is possible to produce microcapsules having uniform capsule membranes and a selected upper limit of permeability.