Title:
THIXOTROPIC ALKALI SALT OF CARBOXYMETHYLCELLULOSE AND ITS PRODUCTION
Document Type and Number:
Japanese Patent JP3870603
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain high degree of substitution and high thixotropic properties by preparing an alkali salt of carboxymethylcellulose which has a degree of substitution of carboxymethyl groups above a specified value and whose aqueous solution prepared so as to provide a specified viscosity gives viscosities at specified spindle revolutions at a ratio below a specified value.
SOLUTION: An alkali such as potassium hydroxide is dissolved in a water- containing organic solvent comprising a hydrophilic organic solvent, such as methyl alcohol, and water at a weight ratio of (80:20) to (95:5) to prepare a solution having a concentration of 40-49 wt.%. This alkali solution is mixed under agitation at 10-50°C with a cellulose raw material such as linter pulp to effect mercerization, an etherifying agent comprising e.g. monochloroacetate is added in small quantities thereto, and the temperature of this mixture is then raised to 60-80°C to etherify. A thixotropic alkali salt of carboxymethylcellulose is thus obtained which has a degree of substitution of carboxymethyl groups of at least 1.0 and whose aqueous solution prepared so as to provide a viscosity measured with a Brookfield viscometer (at 25°C, at a spindle revolution of 30 rpm) of 10,000 mPa.s gives viscosities at spindle revolutions of 60 rpm and 6 rpm at a ratio of at most 0.6:1.
Inventors:
Shinji Sato
Koji Hosokawa
Nobuhiro Hanada
Hiroaki Namba
Koji Hosokawa
Nobuhiro Hanada
Hiroaki Namba
Application Number:
JP9157699A
Publication Date:
January 24, 2007
Filing Date:
March 31, 1999
Export Citation:
Assignee:
NIPPON PAPER INDUSTRIES CO.,LTD.
International Classes:
C08B11/12; C08L1/00; (IPC1-7): C08B11/12; C08L1/00
Domestic Patent References:
| JP9075014A | ||||
| JP9075009A | ||||
| JP7048401A |
Attorney, Agent or Firm:
Kazuo Kawasumi