The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 07, 1980
Filed:
Sep. 20, 1978
Shin-Etsu Chemical Co., Ltd., , JP;
Abstract
A novel cellulose derivative provided in this invention is a mixed ester of an alkoxy or hydroxyalkoxy substituted cellulose ether, prepared by the esterification reaction of the ether with succinic anhydride and an anhydride of an aliphatic monocarboxylic acid. The cellulose derivatives are advantageous because of their capability of producing enteric coatings having sufficient flexibility without the use of a plasticizer as well as by their chemical and physical stability against moisture, and also by easy purification after completion of the esterification reaction. The coatings produced from the derivatives have a similar chemical and physical stability. The cellulose derivatives are useful for the enteric coating of pharmaceutical dosage forms and also for providing halation-preventing layers on photographic films.