The agitation aerofoil for nida, it is provided in nida and the production mannered null revolving shaft and

摘要

PROBLEM TO BE SOLVED: To provide stirring blades for a kneader by which no dead space is formed and compression and compaction of solid components are suppressed. ;SOLUTION: These stirring blades are stirring blades for a kneader having an and blades 4 extended out of the circumference of the axis and the tip end parts of the blades 4 are formed into a saw toothed shape and at the same time the valley parts 6 of the saw toothed shape are expanded toward the rear sides from the front side of the stirring blades in the rotary direction. The bottom parts 7 of the valley parts 6 of the saw toothed shape may be tilted downward at, for example 5-70° degree tilting angle, toward the rear side from the front side of a stirring blade in the rotary direction. Using a kneader having such blades for a kneader, cellulose is acetylated by an acetylating agent in the presence of an oxidation catalyst, so that uniform cellulose acetate in which no non reacted cellulose exists can be obtained.;COPYRIGHT: (C)1997,JPO