Title:
METHOD FOR PRODUCING CARBOXYMETHYL CELLULOSE OR SALT THEREOF
Document Type and Number:
Japanese Patent JP2019059856
Kind Code:
A
Abstract:
To provide a method for producing a carboxymethyl cellulose or a salt thereof which has less decrease in viscosity for a long time and excellent storage stability.SOLUTION: There is provided a method for producing a carboxymethyl cellulose or a salt thereof which comprises: an alkali cellulose formation step (step 1) of reacting cellulose and an alkali in the presence of a mixed solvent containing water and an organic solvent; an etherification step (step 2) of reacting the alkali cellulose obtained in the step 1 and an etherifying agent; a purification step (step 3) of washing and drying the reaction mixture obtained in the step 2; and a pulverization step (step 4) of pulverizing the purified product obtained in the step 3, wherein the step 1 is conducted so that the concentration of the alkali in water is 0.5 mol% or more and 1.0 mol% or less using 2.0 mol or more and 2.5 mol or less of the alkali and 10 mol or more and 15 mol or less of water per 1 mol of an anhydroglucose unit constituting the cellulose.SELECTED DRAWING: None
Inventors:
KAKUBARI RYO
Application Number:
JP2017186155A
Publication Date:
April 18, 2019
Filing Date:
September 27, 2017
Export Citation:
Assignee:
DAI ICHI KOGYO SEIYAKU CO LTD
International Classes:
C08B15/04
Domestic Patent References:
| JPH10158301A | 1998-06-16 | |||
| JP2008222859A | 2008-09-25 | |||
| JP2013523929A | 2013-06-17 | |||
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Foreign References:
| WO2016031449A1 | 2016-03-03 | |||
| WO2017145904A1 | 2017-08-31 |