Patent US3347847A successfully refreshed from Google Patents.
US3347847A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of watersoluble hydroxyethyl cellulose
Assignee: Henkel AG and Co KGaA
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Filing: 1965-04-28
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Granted: 1967-10-17
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Expires: 1985-04-28
Abstract
No abstract record available.
Inventors
- 👤 Engelskirchen Konrad
- 👤 Galinke Joachim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:16
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/20; C08B11/02; C08B11/04; C08B11/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
A PROCESS FOR THE PURIFICATION OF A HYDROXYETHYL CELLULOSE WHICH COMPRISES REACTING AN ACIDIFIED HYDROXYETHYL CELLULOSE WHICH MAY CONTAIN A SUBSTITUENT SELECTED FROM THE GROUP CONSISTING OF HYDROXY LOWER ALKYL AND LOWER ALKYL HAVING SULFATE ASH CONTENT IN EXCESS OF 2% WITH 0.25 TO 2% BY WEIGHT OF GLYOXAL AT AN ACID PH AND AT A TEMPERATURE BETWEEN 40 AND 90*C., SEPARATING AND DRYING THE REACTION PRODUCT, WASHING THE DRIED REACTION PRODUCT WITH WATER HAVING A PH OF 2 TO 6 AT A TEMPERATURE OF 0 TO 30*C. TO WASH OUT SALTS AND RECOVERING THE PURIFIED HYDROXYETHYL CELLULOSE HAVING A LOW SULFATE ASH CONTENT.
Claim 2
Dependent Claim
104 words
A PROCESS FOR THE PURIFICATION OF A HYDROXYETHYL CELLULOSE WHICH COMPRISES REACTING AN ACIDIFIED HYDROXYETHYL CELLULOSE WHICH MAY CONTAIN A SUBSTITUENT SELECTED FROM THE GROUP CONSISTING OF HYDROXY LOWER ALKYL AND LOWER ALKYL HAVING SULFATE ASH CONTENT IN EXCESS OF 2% WITH 0.25 TO 2% BY WEIGHT OF GLYOXAL AT AN ACID PH AND AT A TEMPERATURE BETWEEN 40 AND 90*C., SEPARATING AND DRYING THE REACTION PRODUCT, WASHING THE DRIED REACTION PRODUCT WITH WATER HAVING A PH OF 2 TO 6 AT A TEMPERATURE OF 0 TO 30*C. TO WASH OUT SALTS AND RECOVERING THE PURIFIED HYDROXYETHYL CELLULOSE HAVING A LOW SULFATE ASH CONTENT.
References Cited (Backward Citations)
US3049537A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-10-16 | 1971-04-17 | 1971-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-10-16 | 1975-04-17 | 1975-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-10-16 | 1979-04-17 | 1979-10-17 | $7700.00 | Window Closed / Lapsed |