Patent US2875045A successfully refreshed from Google Patents.
US2875045A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alum containing antioxidant and manufacture of sized paper therewith
Assignee: Wyeth Holdings LLC
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Filing: 1955-04-28
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Granted: 1959-02-24
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Expires: 1975-04-28
Abstract
No abstract record available.
Inventors
- 👤 Lurie David
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:47
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/63; D21H17/66; D21H17/62
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
A COMPOSITION FOR USE IN PAPER MAKING COMPRISING PAPERMAKER''S ALUM AND A WATER-SOLUBLE IONIZABLE THIOSULFATE, SAID CONTAINING A MINOR AMOUNT OF AT LEAST ONE IRON SULFATE AS IMPURITY, THE AMOUNT OF SAID THIOSULFATE BEING SUFFICIENT (1) TO REDUCE ANY TRIVALENT IRON PRESENT TO FERROUS IRON AND (2) TO PROVIDE A SMALL BUT EFFECTIVE AMOUNT OF SAID THISULFATE AS ANTIOXIDANT FOR SAID FERROUS IRON.
Claim 2
Dependent Claim
63 words
A COMPOSITION FOR USE IN PAPER MAKING COMPRISING PAPERMAKER''S ALUM AND A WATER-SOLUBLE IONIZABLE THIOSULFATE, SAID CONTAINING A MINOR AMOUNT OF AT LEAST ONE IRON SULFATE AS IMPURITY, THE AMOUNT OF SAID THIOSULFATE BEING SUFFICIENT (1) TO REDUCE ANY TRIVALENT IRON PRESENT TO FERROUS IRON AND (2) TO PROVIDE A SMALL BUT EFFECTIVE AMOUNT OF SAID THISULFATE AS ANTIOXIDANT FOR SAID FERROUS IRON.
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) | 1962-02-23 | 1962-08-25 | 1963-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-02-23 | 1966-08-25 | 1967-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-02-23 | 1970-08-25 | 1971-02-24 | $7700.00 | Window Closed / Lapsed |