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:
May. 11, 1982
Filed:
Aug. 29, 1980
Richard J Brewer, Kingsport, TN (US);
Brice S Wininger, Kingsport, TN (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
Disclosed is a catalyst and a method of preparing lower fatty acid esters of cellulose which comprises esterifying at a temperature of between about 75.degree. C. and about 110.degree. C. a cellulose compound having esterifiable hydroxyl groups with an esterifying bath comprising an organic acid anhydride, a diluent, and a catalyst comprising (a) from about 0.3 to about 3.0% by weight, based on the weight of cellulose, of an acid selected from the group consisting of sulfuric acid, p-toluene sulfonic acid, methane sulfonic acid, methane disulfonic acid and m-benzene disulfonic acid, and (b) from about 0.05 to about 0.3% by weight, based on the weight of cellulose, of a dialkyl phosphite, the alkyl groups of which contain from 2 to 4 carbon atoms, the weight ratio of said bath to the cellulose being between about 5:1 and about 10:1.