US2883311A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and composition for treating aluminum and aluminum alloys
Assignee: Boeing Helicopters Co
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Filing: 1956-10-01
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Granted: 1959-04-21
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Expires: 1976-10-01
Abstract
No abstract record available.
Inventors
- 👤 Halpert David
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:49
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/02; C23G1/12; C23G1/125
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
THE PROCESS OF TREATING ALUMINUM AND ITS ALLOYS WHICH COMPRISES IMMERSING THE METAL IN AN AQUEOUS SOLUTION CONTAINING 8 TO 98% NITRIC ACID (70% CONCENTRATE) AND CONTAINING FLUORIDE AND CHROMATE IONS IN CONCENTRATIONS CORRESPONDING TO THAT OBTAINED IN A SOLUTION CONTAINING 1 TO 45 GRAMS OF SODIUM FLUORIDE PER LITER OF SOLUTION AND 1 TO 400 GRAMS OF ANHYDROUS CHROMIC ACID PER LITER OF SOLUTION FOR A TIME SUFFICIENT TO INITIALLY REDUCE THE SURFACE REISITANCE OF THE METAL TO BELOW 100 MICROHMS, REMOVING THE METAL FROM SAID AQUEOUS SOLUTION BEFORE THE SURFACE RESISTANCE AGAIN REACHES 100 MICROHMS AND THEREAFTER RINSING THE THUS TREATED METAL.
Claim 2
Dependent Claim
104 words
THE PROCESS OF TREATING ALUMINUM AND ITS ALLOYS WHICH COMPRISES IMMERSING THE METAL IN AN AQUEOUS SOLUTION CONTAINING 8 TO 98% NITRIC ACID (70% CONCENTRATE) AND CONTAINING FLUORIDE AND CHROMATE IONS IN CONCENTRATIONS CORRESPONDING TO THAT OBTAINED IN A SOLUTION CONTAINING 1 TO 45 GRAMS OF SODIUM FLUORIDE PER LITER OF SOLUTION AND 1 TO 400 GRAMS OF ANHYDROUS CHROMIC ACID PER LITER OF SOLUTION FOR A TIME SUFFICIENT TO INITIALLY REDUCE THE SURFACE REISITANCE OF THE METAL TO BELOW 100 MICROHMS, REMOVING THE METAL FROM SAID AQUEOUS SOLUTION BEFORE THE SURFACE RESISTANCE AGAIN REACHES 100 MICROHMS AND THEREAFTER RINSING THE THUS TREATED METAL.
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) | 1962-04-20 | 1962-10-20 | 1963-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-20 | 1966-10-20 | 1967-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-20 | 1970-10-20 | 1971-04-21 | $7700.00 | Window Closed / Lapsed |