Patent ID: 11931711
Assignee: ENCAPSYS, LLC
Field: Pharmaceuticals (Chemistry)
Classification: CPC B  C  A | IPC B  C

Claim 11:
12. A process for preparing a cluster of microcapsules according to claim 1 encapsulating an oil phase, the cluster being substantially irreversibly agglomerated, the process comprising:
dispersing an oil soluble amine modified polyfunctional polyvinyl monomer or oligomer and an oil soluble bi- or polyfunctional vinyl monomer or oligomer along with a free radical initiator and an organic acid and a core material into an internal phase oil;
a first heating step comprising, heating for a time and temperature sufficient to pre-polymerize the amine modified polyfunctional polyvinyl monomer or oligomer and oil soluble bi- or polyfunctional vinyl monomer or oligomer;
adding to the internal phase oil a water phase in excess comprising a dispersion in water of a polyacrylic or poly(meth)acrylic acid, a free radical initiator, and an emulsifying agent;
emulsifying the oil phase into the water phase forming an emulsion of droplets of the oil phase dispersed in the water phase;
heating the emulsion for a time and temperature sufficient to decompose the free radical initiator in the oil and water phases thereby forming microcapsule wall material at the interface of the water and oil phases, the microcapsules encapsulating the oil phase droplets;
adding a polyvalent cation to the emulsion; and,
further heating for a time sufficient to polymerize the wall material and agglomerate the wall material, the polyvalent cation being incorporated into the microcapsule wall, thereby forming the cluster of microcapsules.