Method for producing hydroxypropyl methylcellulose acetate succinate
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsShinnosuke INADA, Kentaro MIKI, Taishi KITAGUCHI, Akira KITAMURA, Mitsuo NARITA
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Abstract
Provided is a method for producing hydroxypropyl methylcellulose acetate succinate by which particle density increment is suppressed and dissolution time is shortened. The method for producing hydroxypropyl methylcellulose acetate succinate essentially includes a liquid removal step, a first drying step, and a second drying step, wherein the first drying step involves drying of hydroxypropyl methylcellulose acetate succinate using a fluid-bed dryer until it reaches a water content of 30% by mass while maintaining the product temperature at 28° C. or lower.
Claims6
A method for producing hydroxypropyl methylcellulose acetate succinate comprising:
- a liquid removal step of
- allowing hydroxypropyl methylcellulose, an acetylating agent, and a succinoylating agent to react with each other in the presence of a catalyst to produce a reaction solution,
- mixing water with the reaction solution to obtain a suspension of hydroxypropyl methylcellulose acetate succinate, and
- removing liquid from the suspension of hydroxypropyl methylcellulose acetate succinate to obtain liquid-removed hydroxypropyl methylcellulose acetate succinate;
- a first drying step of drying the liquid-removed hydroxypropyl methylcellulose acetate succinate using a fluid-bed dryer until it reaches a water content of 30% by mass while maintaining the product temperature at 28° C. or lower to obtain first dried hydroxypropyl methylcellulose acetate succinate;
- and
- a second drying step of further drying the first dried hydroxypropyl methylcellulose acetate succinate to obtain hydroxypropyl methylcellulose acetate succinate.
Dependencies are inferred from the claim text.