Producing method of cellulose polymer
AssigneeFuji Photo Film Co., Ltd.
InventorsTadahisa Sato, Katsuyoshi Yamakawa, Hiroshi Onishi, Tadahiro Tsujimoto
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Abstract
A producing method of a cellulose polymer powder is provided, which comprises dissolving a cellulose polymer by exposure to an organic solvent containing, as the main component, an ester-based solvent having from 2 to 8 carbon atoms, a ketone-based solvent having from 4 to 10 carbon atoms, or an alcohol-based solvent having from 3 to 6 carbon atoms, and carbon dioxide, and then removing the carbon dioxide and the organic solvent from the solution. A producing method of an organic solvent solution of a cellulose polymer is also provided.
Claims8
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.
A process for producing an organic solvent solution of a cellulose polymer which comprises 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, 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 the degree of acetylation of 55.0% or more and the concentration of the polymer in the organic solvent solution is 10 mass% or more.
Dependencies are inferred from the claim text.