Patent US2841579A successfully refreshed from Google Patents.
US2841579A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Depolymerization of cellulose in alkaline medium
Assignee: International Paper Canada Inc
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Filing: 1954-04-15
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Granted: 1958-07-01
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Expires: 1974-04-15
Abstract
No abstract record available.
Inventors
- 👤 Jacques A Villefroy
- 👤 William R Saxton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:01
CPC Classifications
C; C08; C08B; C08B1/00; C08B1/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
59 words
THE METHOD OF TREATING CELLULOSE WHICH COMPRISES AGING ALKALI CELLULOSE IN THE PRESENCE OF A METALLIC OXIDATION CATALYST SELECTED FROM THE GROUP CONSISTING OF COBALT, MANGANESE AND IRON AND AN AGENT SELECTED FROM THE GROUP CONSISTING OF TARTARIC AND CITRIC ACIDS AND THEIR SALTS, SAID AGENT BEING EFFECTIVE TO PREVENT PRECIPITATION OF SAID CATALYST WITHOUT INHIBITING ITS CATALYTIC ACTIVITY.
Claim 2
Independent Claim
59 words
THE METHOD OF TREATING CELLULOSE WHICH COMPRISES AGING ALKALI CELLULOSE IN THE PRESENCE OF A METALLIC OXIDATION CATALYST SELECTED FROM THE GROUP CONSISTING OF COBALT, MANGANESE AND IRON AND AN AGENT SELECTED FROM THE GROUP CONSISTING OF TARTARIC AND CITRIC ACIDS AND THEIR SALTS, SAID AGENT BEING EFFECTIVE TO PREVENT PRECIPITATION OF SAID CATALYST WITHOUT INHIBITING ITS CATALYTIC ACTIVITY.
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) | 1961-06-30 | 1961-12-30 | 1962-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-30 | 1965-12-30 | 1966-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-30 | 1969-12-30 | 1970-07-01 | $7700.00 | Window Closed / Lapsed |