Patent ID: 9340624
Filing Date: 2016-05-17
CPC Classification: A61K,C08B,C08J,C08L,C09D,Y10T

Claim Text:
1. A process for producing a particulate cellulose derivative comprising the steps of A) providing a moist cellulose derivative having a moisture content of from 25 to 95 percent, based on the total weight of the moist cellulose derivative with the proviso that no substantial amount of a surface-treatment additive is added to the cellulose derivative, B) grinding and partially drying the moist cellulose derivative in a gas-swept impact mill wherein a gas fed into the impact mill has a temperature of 100° C. or less; C) contacting the ground and partially dried cellulose derivative with an additional amount of a drying gas outside the gas-swept impact mill, wherein the additional amount of drying gas outside the gas-swept impact mill has a higher temperature than the gas fed into the impact mill; and D) subjecting the cellulose derivative to partial depolymerization after having contacted the cellulose derivative with the drying gas in step C) to produce the particulate cellulose derivative.