Patent US2842435A successfully refreshed from Google Patents.
US2842435A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods of stripping tin and tin alloy surface coatings from iron and iron alloy articles
Assignee: AT&T Inc
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Filing: 1955-12-01
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Granted: 1958-07-08
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Expires: 1975-12-01
Abstract
No abstract record available.
Inventors
- 👤 Michael G Milo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:51
CPC Classifications
C; C22; C22B; C22B25/00; C22B25/06; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
151 words
THE PROCESS OF STRIPPING A SURFACE COATING CONSISTING PRINCIPALLY OF TIN FROM AN ARTICLE MADE OF A METAL OF THE GROUP CONSISTING OF IRON, STEEL AND ALLOYS OF IRON AND STEEL, WHICH COMPRISES IMMERSING SUCH A COATED ARTICLE IN AN ACID TIN-STRIPPING BATH CONTAINING ANTIMONY TRIOXIDE UNTIL THE COATING HAS BEEN STRIPPED FROM THE ARTICLE WHEREBY AN ANTIMONY CONTAINING SMUT CAPABLE OF PENETRATION BY COPPER IONS FORMS ON THE THE ARTICLE, TREATING THE ARTICLE WITH A SOLUTION OF A COPPER SALT WHEREBY COPPER IS PRECIPITATED FROM THE SOLUTION ON THE SMUT SO AS TO FORM A COPPER FILM ON THE SURFACE OF THE ARTICLE UNDER THE SMUT BY COPPER ION PENETRATION THERETHROUGH, CONVERTING THE PRECIPITATED COPPER INTO A COPPER SULPHIDE, AND TREATING THE ARTICLE IN AN ALKALI CYANIDE BATH TO DISSOLVE THE COPPER INT HE COPPER SULPHIDE, WHEREBY THE SURFACE OF THE ARTICLE IS CAUSED TO BE CLEAN AND SUBSTANTIALLY SMUT-FREE.
Claim 2
Dependent Claim
151 words
THE PROCESS OF STRIPPING A SURFACE COATING CONSISTING PRINCIPALLY OF TIN FROM AN ARTICLE MADE OF A METAL OF THE GROUP CONSISTING OF IRON, STEEL AND ALLOYS OF IRON AND STEEL, WHICH COMPRISES IMMERSING SUCH A COATED ARTICLE IN AN ACID TIN-STRIPPING BATH CONTAINING ANTIMONY TRIOXIDE UNTIL THE COATING HAS BEEN STRIPPED FROM THE ARTICLE WHEREBY AN ANTIMONY CONTAINING SMUT CAPABLE OF PENETRATION BY COPPER IONS FORMS ON THE THE ARTICLE, TREATING THE ARTICLE WITH A SOLUTION OF A COPPER SALT WHEREBY COPPER IS PRECIPITATED FROM THE SOLUTION ON THE SMUT SO AS TO FORM A COPPER FILM ON THE SURFACE OF THE ARTICLE UNDER THE SMUT BY COPPER ION PENETRATION THERETHROUGH, CONVERTING THE PRECIPITATED COPPER INTO A COPPER SULPHIDE, AND TREATING THE ARTICLE IN AN ALKALI CYANIDE BATH TO DISSOLVE THE COPPER INT HE COPPER SULPHIDE, WHEREBY THE SURFACE OF THE ARTICLE IS CAUSED TO BE CLEAN AND SUBSTANTIALLY SMUT-FREE.
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) | 1961-07-07 | 1962-01-06 | 1962-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-07 | 1966-01-06 | 1966-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-07 | 1970-01-06 | 1970-07-08 | $7700.00 | Window Closed / Lapsed |