PURPOSE: To prepare the titled drug without using post-treatment, by coating a solid preparation with a specific aqueous solution containing an enteric coating agent and ammonia.
CONSTITUTION: A drug coated with enteric coating can be prepared by coating a solid preparation (e.g. a tablet composed mainly of erythyromycin) with an aqueous solution containing (A) a cellulose derivative wherein at least a part of the carboxyl groups are acid form (e.g. hydroxypropyl methylcellulose phthalate) and (B) ammonia. The cellulose derivative wherein the carboxyl groups are converted into ammonium salts, can be applied in the form of an aqueous solution without using an organic solvent, and moreover, the post-treatment such as neutralization, etc. is completely unnecessary to obtain the enteric coating.
UCHIYAMA NOBUO
JINUSHI KIYOTO
HARA KANEO
MITSUNAGA TAKAYOSHI
UMETSU TADASHI
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