METHOD FOR CROSSLIFT OF HYALURONIC ACID, METHOD FOR PREPARATION OF INJECTION HYDROGEL, HYDROGEL AND USE THEREOF Russian patent published in 2019 - IPC A61K8/73 A61K31/738 C08B37/08 C08J3/75 C08J3/24 C08K3/11 

FIELD: cosmetology.

SUBSTANCE: group of inventions refers to cosmetology and medicine. Cross-linking method of hyaluronic acid or its derivative involves preparation of a first aqueous phase of partially cross-linked hyaluronic acid using a cross-linking agent, which is not converted into particles; preparing at least one second aqueous phase of partially cross-linked hyaluronic acid using a cross-linking agent which is not converted into particles; where second phase has degree of partial stapling, different from degree of cross-linking of first phase; adding a second phase to the first phase and then mixing said phases, where first and second phases in mixture are equal or different; continuation of cross-linking reaction of the mixture by controlling temperature and duration of reaction, wherein method of cross-linking is carried out without adding particles of cross-linked hyaluronic acid. Also disclosed is an injectable hydrogel, a method for preparation thereof and use thereof for preparing a cosmetic, cosmeceutical and therapeutic composition.

EFFECT: group of inventions provides viscoelastic hydrogel with optimized remanence.

21 cl, 7 dwg, 8 ex, 1 tbl