Process for obtaining microcapsules
First Claim
Patent Images
1. A continuous process for preparing an aqueous dispersion of microcapsules with an encapsulation efficiency of the active principle ≧
- 98%, the microcapsules showing an homogeneous granulometric distribution as herein below defined and encapsulating water insoluble active principles to be used in the pharmaceutical and agrochemical field, comprising;
(1) preparation in a first reactor under stirring of an aqueous solution containing one or more surfactants,(2) preparation in a second reactor under stirring of a solution comprising an active principle immiscible in an aqueous phase and a first monomeric component,simultaneous feeding to a tubular reactor of a stream of the aqueous solution (1) and of a stream of solution (2), the ratio of stream solution (2)/stream solution (1) being between 0.5 and 2.0, the streams (1) and (2) being under turbulent flow conditions in the reactor,then, optionally in a time of 0-10 seconds, feeding to the reactor under turbulent flow conditions stream (3) comprising a second monomeric component, the equivalent ratio between the first monomeric component and the second monomeric component being comprised between 0.9 and 1.1,streams (1), (2) and (3) being continuously fed to the tubular reactor;
wherein the substantial homogeneous granulometric distribution of the microcapsules is defined as a b)/a) ratio, wherein b) is the average diameter determined on the smallest 90% of the microcapsules and a) is the average diameter determined on the smallest 50% of the microcapsules, being comprised between 1.5 and 2.5, b) being lower than 15 μ
m, streams (1), (2), and (3) having separate inlets into the reactor.
1 Assignment
0 Petitions
Accused Products
Abstract
A continuous process for preparing microcapsules containing water-insoluble active principles, comprising:
- (1) preparing, in a first reactor, an aqueous solution containing one or more surfactants,
- (2) preparing, in a second reactor, a solution comprising at least an active principle immiscible in an aqueous phase and a first component for preparing a polycondensation polymer for forming the microcapsule shell,
- simultaneously feeding to a tubular reactor of a stream of aqueous solution (1) and solution (2), the ratio of solution (2)/solution (1) being between 0.5 and 2.0,
- inletting a stream (3) of a second component for preparing the polycondensation polymer into the reactor, wherein stream (3) reacts with the first component,
- wherein the streams are under turbulent flow conditions in the tubular reactor, and are continuously fed to the tubular reactor,
- and wherein the ratio between the equivalents of the first component and second component are between 0.9 and 1.1.
6 Citations
17 Claims
-
1. A continuous process for preparing an aqueous dispersion of microcapsules with an encapsulation efficiency of the active principle ≧
- 98%, the microcapsules showing an homogeneous granulometric distribution as herein below defined and encapsulating water insoluble active principles to be used in the pharmaceutical and agrochemical field, comprising;
(1) preparation in a first reactor under stirring of an aqueous solution containing one or more surfactants, (2) preparation in a second reactor under stirring of a solution comprising an active principle immiscible in an aqueous phase and a first monomeric component, simultaneous feeding to a tubular reactor of a stream of the aqueous solution (1) and of a stream of solution (2), the ratio of stream solution (2)/stream solution (1) being between 0.5 and 2.0, the streams (1) and (2) being under turbulent flow conditions in the reactor, then, optionally in a time of 0-10 seconds, feeding to the reactor under turbulent flow conditions stream (3) comprising a second monomeric component, the equivalent ratio between the first monomeric component and the second monomeric component being comprised between 0.9 and 1.1, streams (1), (2) and (3) being continuously fed to the tubular reactor; wherein the substantial homogeneous granulometric distribution of the microcapsules is defined as a b)/a) ratio, wherein b) is the average diameter determined on the smallest 90% of the microcapsules and a) is the average diameter determined on the smallest 50% of the microcapsules, being comprised between 1.5 and 2.5, b) being lower than 15 μ
m, streams (1), (2), and (3) having separate inlets into the reactor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
- 98%, the microcapsules showing an homogeneous granulometric distribution as herein below defined and encapsulating water insoluble active principles to be used in the pharmaceutical and agrochemical field, comprising;
Specification