Process for producing hydroxypropylmethylcellulose acetate succinate (HPMCAS) particles with controlled particle size distribution, and HPMCAS powder

摘要

The present invention relates to a method for producing hydroxypropyl methylcellulose acetate succinate (HPMCAS) particles and hydroxypropylmethylcellulose acetate succinate (HPMCAS) particles. In the method for producing the hydroxypropylmethylcellulose acetate succinate (HPMCAS) particles, hydroxypropylmethylcellulose (HPMC), acetic anhydride and succinic anhydride are esterified in a reaction medium in the presence of a catalyst. Including a step of obtaining a reaction liquid containing methylcellulose acetate succinate (HPMCAS) (esterification reaction stage) and a step of continuously or intermittently adding the reaction liquid to water to generate particles (particle formation stage) .