US4001210A
Expired / Lapsed
US
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Process for manufacturing cellulose containing 2,3-dihydroxypropyl ether groups
Assignee: Henkel AG and Co KGaA
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Filing: 1975-03-17
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Granted: 1977-01-04
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Expires: 1995-03-17
Abstract
Abstract A process for the manufacture of cellulose containing 2,3-dihydroxypropyl ether groups, the so-called glycerol ether of cellulose, together with borate ions comprises reacting alkali cellulose with glycidol of one of its derivatives reacting like glycidol under the reaction conditions, and treating the resulting product with borate ions whereby aqueous solutions of the obtained products are especially low in salt or are highly viscous, as well as the 2,3-dihydroxy propyl ether of cellulose containing borate ions produced by this process, along with an aqueous composition comprising water and a mixture of said 2,3-dihydroxypropyl ether of cellulose and borate ions.
Inventors
- 👤 Konrad Engelskirchen
- 👤 Joachim Galinke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:11
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/02; C08B11/04; C08B11/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
147 words
In the process for the preparation of the 2,3-dihydroxypropyl ether of cellulose wherein an alkali cellulose prepared by reacting cellulose with an alkali metal hydroxide in weight ratio of about 1:0.05 to 0.5 is reacted with an etherifying agent selected from the group consisting of glycidol and a derivative of glycidol which reacts like glycidol under the reaction conditions, the mol ratio of said cellulose to said etherifying agent being from 1:1 to 1:10, at a temperature between 20° C. to 120° C., under etherifying conditions in suspension in an aqueous solution of an inert organic liquid having a pH over 7.5, and recovering the 2,3-dihydroxypropyl ether of cellulose thereby formed: the improvement which comprises introducing a compound which provides borate ions into said cellulose ether suspension thereby neutralizing said suspension, and washing said ether thereby removing the salts in solution formed by addition of said compound.
Claim 2
Dependent Claim
147 words
In the process for the preparation of the 2,3-dihydroxypropyl ether of cellulose wherein an alkali cellulose prepared by reacting cellulose with an alkali metal hydroxide in weight ratio of about 1:0.05 to 0.5 is reacted with an etherifying agent selected from the group consisting of glycidol and a derivative of glycidol which reacts like glycidol under the reaction conditions, the mol ratio of said cellulose to said etherifying agent being from 1:1 to 1:10, at a temperature between 20° C. to 120° C., under etherifying conditions in suspension in an aqueous solution of an inert organic liquid having a pH over 7.5, and recovering the 2,3-dihydroxypropyl ether of cellulose thereby formed: the improvement which comprises introducing a compound which provides borate ions into said cellulose ether suspension thereby neutralizing said suspension, and washing said ether thereby removing the salts in solution formed by addition of said compound.
Claim 3
Dependent Claim
16 words
The process of claim 1, wherein said borate ions are introduced by addition of boric acid.
Claim 4
Dependent Claim
66 words
The process of claim 1, wherein said borate ions are introduced by neutralizing the alkali present by addition of a boron material selected from the group consisting of (a) boric acid, (b) a mixture of boric acid with an acid selected from the group consisting of hydrochloric acid, phosphoric acid, nitric acid, acetic acid and propionic acid, and (c) an easily saponifiable derivative of boric acid.
Claim 5
Dependent Claim
17 words
The process of claim 3, wherein said material is a mixture of boric acid and hydrochloric acid.
Claim 6
Dependent Claim
19 words
The process of claim 3, wherein said boron material is added after said reaction has been completely carried out.
Claim 7
Dependent Claim
20 words
The process of claim 1, wherein said borate ions are introduced by addition of a lower-alkyl ester of boric acid.
Claim 8
Dependent Claim
11 words
The process of claim 6, wherein said ester is trimethyl borate.
Claim 9
Dependent Claim
14 words
A 2,3-dihydroxypropyl ether of cellulose containing 1% to 10% by weight of borate ions.
Claim 10
Dependent Claim
14 words
A 2,3-dihydroxypropyl ether of cellulose containing 1% to 10% by weight of borate ions.
Claim 11
Dependent Claim
12 words
The cellulose ether-borate ion composition of claim 8 in substantially dry state.
Claim 12
Dependent Claim
22 words
An aqueous solution containing from 0.5% to 5% by weight of a mixture of an ether-borate ion composition according to claim 8.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-04 | 1980-07-05 | 1981-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-04 | 1984-07-05 | 1985-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-04 | 1988-07-05 | 1989-01-04 | $7700.00 | Window Closed / Lapsed |