Patent US3444253A successfully refreshed from Google Patents.
US3444253A
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Addition reactions of butadiene catalyzed by copper (i) zeolites
Assignee: Union Carbide Corp
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Filing: 1967-09-20
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Granted: 1969-05-13
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Expires: 1987-09-20
Abstract
No abstract record available.
Inventors
- 👤 Hans K Reimlinger
- 👤 Ernest H De Ruiter
- 👤 Ulrich K Kruerke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:13
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/02; C07C2/50; C07C2/52; C07C2529/00; C07C2529/04; C07C2529/06; C07C2529/08; C07C2601/00; C07C2601/12; C07C2601/16; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1868127A
Cited
US2352606A
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US2431403A
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US2544808A
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US3236762A
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US3104270A
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US3013985A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-12 | 1972-11-11 | 1973-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-12 | 1976-11-11 | 1977-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-12 | 1980-11-11 | 1981-05-13 | $7700.00 | Window Closed / Lapsed |