Method for producing hypromellose acetate succinate

Number of patents in Portfolio can not be more than 2000

United States of America

PATENT NO 11319385
APP PUB NO 20200031954A1
SERIAL NO

16521253

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Abstract

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There is provided a method for producing hypromellose acetate succinate (HPMCAS), the method not requiring any special device and facilitating removal of impurities. More specifically, there is provided a method for producing HPMCAS, including an esterification step of esterifying hypromellose with an acetylating agent and a succinoylating agent in the presence of an aliphatic carboxylic acid to obtain a reaction product solution containing HPMCAS; a precipitation step of precipitating the HPMCAS by mixing the reaction product solution with water to obtain a suspension of the precipitated HPMCAS; a neutralization step of neutralizing the suspension with a basic substance to obtain a neutralized suspension; and a washing step of washing the HPMCAS contained in the neutralized suspension to obtain the washed HPMCAS.

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Patent Owner(s)

Patent OwnerAddress
SHIN-ETSU CHEMICAL CO LTDTOKYO TOKYO METROPOLIS

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Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Kitaguchi, Taishi Niigata, JP 13 4
Kitamura, Akira Niigata, JP 54 156
Narita, Mitsuo Niigata, JP 58 162
Tsuchida, Akiko Niigata, JP 4 1

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