Patent US3245841A successfully refreshed from Google Patents.
US3245841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of iron powder having high electrical resistivity
Assignee: Individual
•
Filing: 1962-08-15
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Granted: 1966-04-12
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Expires: 1982-08-15
Abstract
No abstract record available.
Inventors
- 👤 Clarke Sydney George
- 👤 Andrew Jack Frederick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:21
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/16; B; B22; B22F; B22F1/00; B22F1/14; B22F1/145; C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/24; C23C22/33; H01F1/20; H01F1/22; H01F1/24; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
97 words
A PROCESS FOR MAKING A HIGHLY RESISTANT IRON POWDER COMPRISING TREATING IRON POWDER WHOSE PARTICLES SIZE IS UP TO 10 MICRONS, WITH 1/2 TO 2 1/2% OF ITS WEIGHT OF PHOSPHORIC ACID AND 1/2 TO 2 1/2% OF ITS WEIGHT OF CHROMIC ACID DISSOLVED IN AT LEAST TWO LITERS OF WATER OF EACH KILOGRAM OF IRON POWDER WITH SUFFICIENT AGITATION TO KEEP THE PARTICLES IN SUSPENSION, UNTIL THE IRON PARTICLES ARE PROVIDED WITH A RESISTANT SURFACE COATING, WHEREBY THE IRON POWDER WHEN FORMED INTO A COMPACT MASS HAS A SPECIFIC RESISTIVITY OF AT LEAST 1 MEGOHM/CM. CUBE.
Claim 2
Dependent Claim
97 words
A PROCESS FOR MAKING A HIGHLY RESISTANT IRON POWDER COMPRISING TREATING IRON POWDER WHOSE PARTICLES SIZE IS UP TO 10 MICRONS, WITH 1/2 TO 2 1/2% OF ITS WEIGHT OF PHOSPHORIC ACID AND 1/2 TO 2 1/2% OF ITS WEIGHT OF CHROMIC ACID DISSOLVED IN AT LEAST TWO LITERS OF WATER OF EACH KILOGRAM OF IRON POWDER WITH SUFFICIENT AGITATION TO KEEP THE PARTICLES IN SUSPENSION, UNTIL THE IRON PARTICLES ARE PROVIDED WITH A RESISTANT SURFACE COATING, WHEREBY THE IRON POWDER WHEN FORMED INTO A COMPACT MASS HAS A SPECIFIC RESISTIVITY OF AT LEAST 1 MEGOHM/CM. CUBE.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-04-11 | 1969-10-11 | 1970-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-04-11 | 1973-10-11 | 1974-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-04-11 | 1977-10-11 | 1978-04-12 | $7700.00 | Window Closed / Lapsed |