US2882189A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alkali metal phosphate coating method for metals and article produced thereby
Assignee: Parker Rust Proof Co
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Filing: 1954-10-20
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Granted: 1959-04-14
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Expires: 1974-10-20
Abstract
No abstract record available.
Inventors
- 👤 William S Russell
- 👤 Robert C Gibson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:28
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/82; C23C22/83; Y; Y10; Y10T; Y10T428/00; Y10T428/27; Y10T428/273
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
93 words
THE METHOD OF TREATING FERROUS SURFACES TO INCREASE THEIR RESISTANCE TO CORROSION AND IMPROVE THE AHERENCE THERETO OF ORGANIC SICCATIVE FINISHES WHICH COMPRISES PROVIDING AN IRON PHOSPHATE COATING THEREON, RINSING SAID PHOSPHATE-COATED SURFACE WITH A CONCENTRATED SOLUTION OF A HEXAVALENT CHROMIUM COMPOND, AND DRYING SAID RINSE ON SAID SURFACE, CONTROLLING THE CONCENTRATION OF SAID RINSE SOLUTION AND THE CONDITIONS OF SAID RINSING OPERATION SO AS TO DEPOSIT AN OVERLAYER OF HEXAVALENT CHROMIUM COMPOUND ON SAID SURFACE WEIGHING AT LEAST 0.6 MG./SQ. FT. AND NOT MORE THAN ABOUT 15 MG./SQ. FT. CALCULATED AS CRO3.
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) | 1962-04-13 | 1962-10-13 | 1963-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-13 | 1966-10-13 | 1967-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-13 | 1970-10-13 | 1971-04-14 | $7700.00 | Window Closed / Lapsed |