Claims
- 1. A method for microencapsulating an agent to form a microencapsulated product, comprising:dissolving a polymer in an effective amount of a solvent, dissolving or dispersing said agent in said effective amount of said solvent, wherein said polymer, said agent and said solvent form a mixture having a continuous phase and wherein the solvent is said continuous phase, and introducing said mixture into an effective amount of a nonsolvent to cause the spontaneous formation of said microencapsulated product, wherein said step of introducing does not include emulsification, agitation, and/or stirring, wherein said solvent and said nonsolvent are miscible and 0<δ solvent −δ nonsolvent <6 wherein the nonsolvent and solvent are used in effective amounts, wherein the effective amount of nonsolvent is tenfold greater than the amount of solvent.
- 2. The method of claim 1 wherein the concentration of the polymer in the solvent is less than 20% weight per volume.
- 3. The method of claim 1 wherein the mixture has a viscosity less than 6 centepoise.
- 4. The method of claim 1 wherein the solvent and nonsolvent are hydrophilic pairs.
Parent Case Info
This application is a divisional of application Ser. No. 08/686,928, filed Jul. 3, 1996, entitled A Process For Preparing Microparticles Through Phase Inversion Phenomena, and now U.S. Pat. No. 6,143,211 which claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 60/001,365, filed Jul. 21, 1995.
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