Patent US2967791A successfully refreshed from Google Patents.
US2967791A
Expired / Lapsed
US
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Process of coating aluminum
Assignee: Parker Rust Proof Co
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Filing: 1957-08-19
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Granted: 1961-01-10
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Expires: 1977-08-19
Abstract
No abstract record available.
Inventors
- 👤 Roy A Halversen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:43
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/86; C23C22/05; C23C22/06; C23C22/34; C23C22/37; C23C22/38
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
A METHOD OF FORMING A COATING ON THE SURFACE OF ALUMINUM WHICH COMPRISES THE STEPS OF CONTACTING THE ALUMINUM SURFACE WITH AN AQUEOUS ACIDIC OPERATING SOLUTION CONTAINING CHROMIC ACID, THE FLUORIDE ION, AND HAVING A FREE ACID OF 3-170 POINTS, WITHDRAWING A PORTION OF SAID OPERATING SOLUTION AND PASSING THE SAID PORTION THROUGH A STRONGLY ACIDIC CATION EXCHANGE RESIN BED AND RETURNING THE EFFLUENT THEREFROM TO SAID PROCESSING SOLUTION, THE QUALITY OF SAID SOLUTION PASSED THROUGH SAID BED BEING SUCH AS TO MAINTAIN THE ALUMINUM CONCENTRATION IN SAID OPERATING SOLUTION IN THE RANGE OF ABOUT 0.005% AND 0.4% BY WEIGHT.
Claim 2
Independent Claim
100 words
A METHOD OF FORMING A COATING ON THE SURFACE OF ALUMINUM WHICH COMPRISES THE STEPS OF CONTACTING THE ALUMINUM SURFACE WITH AN AQUEOUS ACIDIC OPERATING SOLUTION CONTAINING CHROMIC ACID, THE FLUORIDE ION, AND HAVING A FREE ACID OF 3-170 POINTS, WITHDRAWING A PORTION OF SAID OPERATING SOLUTION AND PASSING THE SAID PORTION THROUGH A STRONGLY ACIDIC CATION EXCHANGE RESIN BED AND RETURNING THE EFFLUENT THEREFROM TO SAID PROCESSING SOLUTION, THE QUALITY OF SAID SOLUTION PASSED THROUGH SAID BED BEING SUCH AS TO MAINTAIN THE ALUMINUM CONCENTRATION IN SAID OPERATING SOLUTION IN THE RANGE OF ABOUT 0.005% AND 0.4% BY WEIGHT.
References Cited (Backward Citations)
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US2777785A
Cited
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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) | 1964-01-10 | 1964-07-11 | 1965-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-01-10 | 1968-07-11 | 1969-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-01-10 | 1972-07-11 | 1973-01-10 | $7700.00 | Window Closed / Lapsed |