US2964432A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for treating metals and product
Assignee: National Steel Corp
•
Filing: 1957-12-13
•
Granted: 1960-12-13
•
Expires: 1977-12-13
Abstract
No abstract record available.
Inventors
- 👤 Howard T Francis
- 👤 Frank H Roebuck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:59
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
A PROCESS FOR TREATING MATERIAL HAVING A ZINC SURFACE TO IMPROVE CORROSION RESISTANCE COMPRISING IMMERSING THE MATERIAL IN A BODY OF TREATING SOLUTION CONSISTING ESSENTIALLY OF AN AQUEOUS SOLUTION OF ZINC NITRATE AND CHROMIC ACID HAVING A MOLAR RATIO OF ZINC NITRATE TO CHROMIC ACID BETWEEN 4:1 TO 1:9 TO PRODUCE A CORROSION RESISTANT FILM ON THE ZINC SURFACE, THE SOLUTION BEING FREE OF A SUBSTANCE WHICH IS A REDUCING AGENT FOR CHROMATE ION, AT LEAST THE ZINC SURFACE OF THE MATERIAL TO BE TREATED BEING INITIALLY AT A TEMPERATURE SUBSTANTIALLY ABOVE ROOM TEMPERATURE AND LESS THAN ABOUT 450*F., REMOVING THE TREATED MATERIAL FROM THE BODY OF SOLUTION, AND THEN SUBJECTING THE TREATED MATERIAL TO AN AQUEOUS RINSE TO REMOVE EXCESS TREATING SOLUTION AND PRODUCE A SUBSTANTIALLY COLORLESS CORROSION RESISTANT FILM ON THE ZINC SURFACE.
Claim 2
Dependent Claim
135 words
A PROCESS FOR TREATING MATERIAL HAVING A ZINC SURFACE TO IMPROVE CORROSION RESISTANCE COMPRISING IMMERSING THE MATERIAL IN A BODY OF TREATING SOLUTION CONSISTING ESSENTIALLY OF AN AQUEOUS SOLUTION OF ZINC NITRATE AND CHROMIC ACID HAVING A MOLAR RATIO OF ZINC NITRATE TO CHROMIC ACID BETWEEN 4:1 TO 1:9 TO PRODUCE A CORROSION RESISTANT FILM ON THE ZINC SURFACE, THE SOLUTION BEING FREE OF A SUBSTANCE WHICH IS A REDUCING AGENT FOR CHROMATE ION, AT LEAST THE ZINC SURFACE OF THE MATERIAL TO BE TREATED BEING INITIALLY AT A TEMPERATURE SUBSTANTIALLY ABOVE ROOM TEMPERATURE AND LESS THAN ABOUT 450*F., REMOVING THE TREATED MATERIAL FROM THE BODY OF SOLUTION, AND THEN SUBJECTING THE TREATED MATERIAL TO AN AQUEOUS RINSE TO REMOVE EXCESS TREATING SOLUTION AND PRODUCE A SUBSTANTIALLY COLORLESS CORROSION RESISTANT FILM ON THE ZINC SURFACE.
References Cited (Backward Citations)
US2206064A
Cited
US2393943A
Cited
GB570054A
Cited
GB600041A
Cited
US2763569A
Cited
US2851386A
Cited
US2904413A
Cited
US2846342A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-12-13 | 1964-06-13 | 1964-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-12-13 | 1968-06-13 | 1968-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-12-13 | 1972-06-13 | 1972-12-13 | $7700.00 | Window Closed / Lapsed |