US3141738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing black-coloured magnetic iron oxide
Assignee: Individual
•
Filing: 1961-09-05
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Granted: 1964-07-21
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Expires: 1981-09-05
Abstract
No abstract record available.
Inventors
- 👤 Kagitani Takeo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:33
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70642; G11B5/70678; G11B5/70684; G11B5/70689; C; C01; C01G; C01G49/00; C01G49/02; C01G49/08; C01P; C01P2006/00; C01P2006/60
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
THE METHOD OF PRODUCING BLACK-COLOURED MAGNETIC IRON OXIDE, WHICH IS MAGNETIC, WHICH CONSISTS IN DISSOLVING A FERROUS COMPOUND WHICH IS A MEMBER OF THE GROUP CONSISTING OF FERROUS SULFATE AND FERROUS CHLORIDE IN SUBSTANTIALLY THEORETICAL AMOUNT IN AN AQUEOUS SOLUTION OF AN ALKALI METAL SALT OF A LOWER MONOCARBOXYLIC ACID WHICH IS A MEMBER OF THE GROUP CONSISTING OF SODIUM ACETATE AND SODIUM FORMATE, AND HEATING THE SOLUTION WITH AERATION TO SUBSTANTIALLY 70-100*C., THE AMOUNT OF THE WATER CONSTITUTING THE AQUEOUS SOLUTION BEING MORE THAN TEN TIMES BY WEIGHT THE AMOUNT OF THE ALKALI SALT.
Claim 2
Independent Claim
95 words
THE METHOD OF PRODUCING BLACK-COLOURED MAGNETIC IRON OXIDE, WHICH IS MAGNETIC, WHICH CONSISTS IN DISSOLVING A FERROUS COMPOUND WHICH IS A MEMBER OF THE GROUP CONSISTING OF FERROUS SULFATE AND FERROUS CHLORIDE IN SUBSTANTIALLY THEORETICAL AMOUNT IN AN AQUEOUS SOLUTION OF AN ALKALI METAL SALT OF A LOWER MONOCARBOXYLIC ACID WHICH IS A MEMBER OF THE GROUP CONSISTING OF SODIUM ACETATE AND SODIUM FORMATE, AND HEATING THE SOLUTION WITH AERATION TO SUBSTANTIALLY 70-100*C., THE AMOUNT OF THE WATER CONSTITUTING THE AQUEOUS SOLUTION BEING MORE THAN TEN TIMES BY WEIGHT THE AMOUNT OF THE ALKALI SALT.
References Cited (Backward Citations)
US2694656A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-07-21 | 1968-01-20 | 1968-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-07-21 | 1972-01-20 | 1972-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-07-21 | 1976-01-20 | 1976-07-21 | $7700.00 | Window Closed / Lapsed |