US 12,453,693 B2
Encapsulated fragrance compounds based on natural amino acids
Julian Alexander Georgi, Holzminden (DE); Benjamin Rost, Bodenwerder (DE); Ralf Bertram, Holzminden (DE); Britta Raabe, Muenden (DE); André Haetzelt, Holzminden (DE); and Joern Wiedemann, Holzminden (DE)
Assigned to SYMRISE AG, Holzminden (DE)
Appl. No. 17/782,466
Filed by SYMRISE AG, Holzminden (DE)
PCT Filed Dec. 5, 2019, PCT No. PCT/EP2019/083903
§ 371(c)(1), (2) Date Jun. 3, 2022,
PCT Pub. No. WO2021/110273, PCT Pub. Date Jun. 10, 2021.
Prior Publication US 2023/0018872 A1, Jan. 19, 2023
Int. Cl. A61K 8/87 (2006.01); A61K 8/06 (2006.01); A61K 8/11 (2006.01); A61K 8/34 (2006.01); A61K 8/41 (2006.01); A61K 8/73 (2006.01)
CPC A61K 8/87 (2013.01) [A61K 8/062 (2013.01); A61K 8/11 (2013.01); A61K 8/345 (2013.01); A61K 8/41 (2013.01); A61K 8/732 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for producing multilayer microcapsules comprising the following steps in this order:
a) forming a first crosslinking layer by:
a1) providing an internal non-aqueous phase comprising at least one isocyanate having two or more isocyanate groups and at least one active ingredient to be encapsulated;
a2) providing an external aqueous phase comprising at least one protective colloid;
a3) mixing the internal non-aqueous phase and the external aqueous phase to obtain an oil-in-water emulsion;
b) forming a second crosslinking layer by addition of an amine which reacts at an acidic pH;
c) forming a third crosslinking layer by addition of a hydroxyl group donor;
d) forming at least a fourth crosslinking layer by adding at least one amine which reacts at an alkaline pH, to obtain multilayer microcapsules;
e) curing the multilayer microcapsules obtained in step d);.