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US3501442A
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US
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Polymerization of lactams in the presence of an organic oxy-acid of phosphorus
Assignee: Imperial Chemical Industries Ltd
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Filing: 1966-06-15
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Granted: 1970-03-17
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Expires: 1986-06-15
Abstract
No abstract record available.
Inventors
- 👤 Harold George Burrows
- 👤 Stephen John Hepworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:23
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/49; C08K5/51; C08K5/53; C08K5/5313; C08B; C08B3/00; C08B3/22; C08B3/30; C08G; C08G69/00; C08G69/02; C08G69/04; C08G69/08; C08G69/14; C08G69/16; C08G69/26; C08G69/28; C08K5/5317; C08L; C08L77/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2510777A
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US3216976A
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US3235534A
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US3376258A
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US3321447A
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US3365428A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-16 | 1973-09-15 | 1974-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-16 | 1977-09-15 | 1978-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-16 | 1981-09-15 | 1982-03-17 | $7700.00 | Window Closed / Lapsed |