Patent US3436437A successfully refreshed from Google Patents.
US3436437A
Expired / Lapsed
US
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Process for recovering high purity isoprene by extractive distillation with methoxypropionitrile
Assignee: Mitsubishi Gas Chemical Co Inc
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Filing: 1966-11-15
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Granted: 1969-04-01
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Expires: 1986-11-15
Abstract
No abstract record available.
Inventors
- 👤 Mitsuo Asaka
- 👤 Makoto Komatsu
- 👤 Susumu Jufiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:34
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/005; C07C7/04; C07C7/05; C07C7/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2768224A
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US2426705A
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US2361493A
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US2407997A
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US2441827A
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US2459403A
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US2851505A
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US3242227A
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US3230157A
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US3317627A
Cited
US3301915A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-03-31 | 1972-09-30 | 1973-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-03-31 | 1976-09-30 | 1977-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-03-31 | 1980-09-30 | 1981-04-01 | $7700.00 | Window Closed / Lapsed |