US2698322A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing solid non-gelled easily filterable carboxymethylcellulose from solid sodium carboxymethylcellulose
Assignee: Wyandotte Chemicals Corp
•
Filing: 1952-04-23
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Granted: 1954-12-28
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Expires: 1972-04-23
Abstract
No abstract record available.
Inventors
- 👤 Clyde W Leaf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:02
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
50 words
A METHOD FOR PREPARING CARBOXYMETHYLCELLULOSE IN A NON-GELLED EASILY FILTERABLE FORM, WHICH COMPRISES ADDING SOLID SODIUM CARBOXYMETHYLCELLULOSE CONTAINING NOT SUBSTANTIALLY MORE THAN 0.5 GYLCOLLIC ACID GROUPS PER GLUCOSE UNIT OF CELLULOSE TO SULFURIC ACID HAVING A CONCENTRATION OF AT LEAST ABOUT 5% AND NOT SUBSTANTIALLY MORE THAN 35%, BY WEIGHT.
Claim 2
Independent Claim
50 words
A METHOD FOR PREPARING CARBOXYMETHYLCELLULOSE IN A NON-GELLED EASILY FILTERABLE FORM, WHICH COMPRISES ADDING SOLID SODIUM CARBOXYMETHYLCELLULOSE CONTAINING NOT SUBSTANTIALLY MORE THAN 0.5 GYLCOLLIC ACID GROUPS PER GLUCOSE UNIT OF CELLULOSE TO SULFURIC ACID HAVING A CONCENTRATION OF AT LEAST ABOUT 5% AND NOT SUBSTANTIALLY MORE THAN 35%, BY WEIGHT.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-12-27 | 1958-06-28 | 1958-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-12-27 | 1962-06-28 | 1962-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-12-27 | 1966-06-28 | 1966-12-28 | $7700.00 | Window Closed / Lapsed |