Hypromellose phthalate and method for producing hypromellose phthalate
US10961323B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 2017 |
| Grant date | Mar 30, 2021 |
| Priority date | — |
| Expiry date | Sep 19, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08B13/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Provided is a method for producing HPMCP capable of reducing the average particle size of HPMCP particles to an intended range without a pulverization step. Specifically provided is a method for producing hypromellose phthalate, comprising an esterification step of reacting hypromellose with an esterification agent in the presence of a catalyst to obtain a reaction solution containing crude hypromellose phthalate, a precipitation step of mixing the reaction solution with water to precipitate the crude hypromellose phthalate, thereby obtaining a hypromellose phthalate suspension, a liquid removal step of removing a liquid from the hypromellose phthalate suspension with a centrifugal decanter to obtain liquid-removed hypromellose phthalate, and a drying step of drying the liquid-removed hypromellose phthalate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.