| 摘要 |
PROBLEM TO BE SOLVED: To provide a cellulose ester useful in remarkably enhancing optical characteristics such as optical isotropy or the like and to provide a film. SOLUTION: The cellulose ester is adjusted so that the total mean degree of substitution is 2.90-2.965; the sum total of mean degrees of substitution at the 2- and 3-positions of glucose units is 1.97 or more; and a half width of the composition distribution is 0.09 or less in terms of degree of substitution. The cellulose ester can be produced in a process for the production of a cellulose ester which comprises the acylation step (i) of acylating cellulose with an acylating agent in the presence of a sulfuric acid catalyst and the aging step (ii) of aging the resulting product in the presence of a sulfuric acid catalyst wherein the acylation in the acylation step (i) is conducted using the acylating agent in an amount of 1.40-2.0 molar equivalents per mol of cellulosic hydroxyl group in the presence of the sulfuric acid catalyst in an amount of 6.5-9.5 pts.wt. per 100 pts.wt. cellulose. COPYRIGHT: (C)2006,JPO&NCIPI
|
