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US3732197A
Expired / Lapsed
US
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Production of alpha-olefin polymers
Assignee: Mitsubishi Chemical Corp
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Filing: 1970-12-07
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Granted: 1973-05-08
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Expires: 1990-12-07
Abstract
Abstract AT LEAST ONE KIND OF TROPYLIUM SALT (CYCLOHEPTATRIENIUM SALT) IN COMBINED WITH A ZIEGLER-NATTA TYPE CATALYST (COMPRISING BASICALLY, A COMPOUND OF A TRANSITION METAL OF GROUP IV, V, OR VI AND AN ORGAOMETALLIC COMPOUND OF A METAL OF GROUP I, II, OR III) TO FORM A HIGHLY EFFECTIVE CATALYST WHEREBY AT LEAST ONE KINE OF A-OLEFIN CAN BE POLYMERIZED TO PRODUCE A-OLEFIN POLYMERS OF HIGH CRYSTALLINITY.
Inventors
- 👤 S Kitagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:01
CPC Classifications
C; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-07 | 1976-11-06 | 1977-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-07 | 1980-11-06 | 1981-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-07 | 1984-11-06 | 1985-05-08 | $7700.00 | Window Closed / Lapsed |