Patent US3640736A successfully refreshed from Google Patents.
US3640736A
Expired / Lapsed
US
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Tarnish-preventive composition comprising hydroxy-containing thiol sulfides
Assignee: Phillips Petroleum Co
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Filing: 1970-09-01
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Granted: 1972-02-08
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Expires: 1990-09-01
Abstract
Abstract A tarnish-preventive composition for silver and copper surfaces comprising: A. HYDROXY-SUBSTITUTED MERCAPTO SULFIDES HAVING THE FORMULA B. An abrasive, and C. THE BALANCE A DILUENT.
Inventors
- 👤 Paul F Warner
- 👤 Edward E Huxley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:50
CPC Classifications
C; C11; C11D; C11D7/00; C11D7/22; C11D7/34
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
12 words
A composition according to claim 1 wherein said compound is 2-mercaptoethyl-2''-hydroxypentadecyl sulfide.
References Cited (Backward Citations)
US3567782A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |