US2806057A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydroxy-substituted tetrahydrophthalic acids, derivatives thereof, and method for producing the same
Assignee: Shell Development Co
•
Filing: 1953-02-24
•
Granted: 1957-09-10
•
Expires: 1973-02-24
Abstract
No abstract record available.
Inventors
- 👤 Finch Harry Dev
- 👤 Seaver A Ballard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:01
CPC Classifications
C; C10; C10M; C10M1/00; C10M1/08; C10M2207/00; C10M2207/10; C10M2207/24; C10N; C10N2010/00; C10N2010/02; C10N2010/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
9 words
A PROCESS FOR PREPARING AN ACID OF THE FORMULA
Claim 2
Dependent Claim
9 words
A PROCESS FOR PREPARING AN ACID OF THE FORMULA
References Cited (Backward Citations)
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US2155639A
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GB493196A
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US2221663A
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US2262002A
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US2251297A
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US2275383A
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US2251298A
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US2275034A
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US2501610A
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US2450627A
Cited
US2475557A
Cited
US2474686A
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US2632011A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-09 | 1961-03-11 | 1961-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-09 | 1965-03-11 | 1965-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-09 | 1969-03-11 | 1969-09-10 | $7700.00 | Window Closed / Lapsed |