EP0055820A1
Expired / Lapsed
EP
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Preparation of CMC with improved substituent uniformity using borax
Assignee: Hercules LLC
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Filing: 1981-10-30
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Granted: —
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Expires: 2001-10-30
Abstract
Abstract Solution qualities of carboxymethyl cellulose are improved by preparing the same with cellulose which has been alkalized in the presence of a borate ion-containing salt.
Inventors
- 👤 Thomas George Majewicz
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 01:08
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/02; C08B11/04; C08B11/10; C08B11/12; C08B1/00; C08B1/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
64 words
A process of preparing carboxymethyl cellulose wherein cellulose is stepped in an alkali metal hydroxide to prepare alkali cellulose and thereafter reacted with sodium monochloroacetate to convert said alkali cellulose to carboxymethyl cellulose, characterized in that the alkali cellulose preparation is carried out in the presence of about 1.5 to 20% by weight, based on the weight of cellulose, of a borate ion-containing salt.
Claim 2
Dependent Claim
64 words
A process of preparing carboxymethyl cellulose wherein cellulose is stepped in an alkali metal hydroxide to prepare alkali cellulose and thereafter reacted with sodium monochloroacetate to convert said alkali cellulose to carboxymethyl cellulose, characterized in that the alkali cellulose preparation is carried out in the presence of about 1.5 to 20% by weight, based on the weight of cellulose, of a borate ion-containing salt.
Claim 3
Dependent Claim
19 words
The method as claimed in claim 1 further characterized in that the borate ion-containing salt is sodium tetraborate decahydrate.
Claim 4
Dependent Claim
27 words
The method as claimed in claim 2 further characterized in that the sodium tetraborate decahydrate is present in the amount of about 3 to 10% by weight.
References Cited (Backward Citations)
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