Patent ID: 6548660
Filing Date: 2003-04-15
Classification: C08B,C08J

Abstract:
A process for producing a cellulose polymer powder which comprises the steps of dissolving a cellulose polymer by exposure to an organic solvent containing, as the main component, a compound selected from the group consisting of methyl acetate, ethyl acetate, methyl ethyl ketone, isopropyl methyl ketone, cyclohexanone, butanol and mixtures thereof, and carbon dioxide, and then removing the carbon dioxide and the organic solvent from the solution, wherein the cellulose polymer is dissolved at a temperature and pressure not lower than the critical temperature and critical pressure of carbon dioxide, the cellulose polymer is cellulose acetate having a degree of acetylation of 55.0% or more, and the concentration of the polymer in the organic solvent solution is 10 mass % or more.