Patent US3639409A successfully refreshed from Google Patents.
US3639409A
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1 3 8-triaza-2-oxo- or thioxo-3-substituted-4-oxo or imin 7 9 9-tetraalkyl spiro(4 o-75)decanes
Assignee: Sankyo Co Ltd
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Filing: 1968-06-19
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Granted: 1972-02-01
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Expires: 1988-06-19
Abstract
Abstract NEW PIPERIDINE-SPIRO-HETEROCYCLES; NAMELY, PIPERIDINESPRIO-IMIDAZOLIDINES, PIPERDINE-SPRIO-HUDATOINS AND PIPERIDINE-SPIRO-OXAZOLIDINES ARE VALUABLE LIGHT STABILIZERS FOR THE PREVENTION OF THE PHOTO-DETERIORATION OF VARIOUS SYNTHETIC POLYMER SUCH AS POLYOLEFIN, POLYURETHANE, POLYAMIDE AND THE LIKE. THESE PIPERLIDINE-SPIRO-HETEROCYCLES ARE PREPARED BY REACTIN 4-CYANO-4-HYDROXY (OR -AMINO)2,2,6,6-TETRASUBSTITURED PIPERIDINE DERIVATIVE WITH ISOCYANATE DERIVATIVE FOLLOWED BY HEAT TREATMENT IN THE PRESENCE OR ABSENCE OF A STRONG MINERAL ACID.
Inventors
- 👤 Keisuke Murayama
- 👤 Syoji Morimura
- 👤 Toshimasa Toda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:52
CPC Classifications
C; C07; C07D; C07D498/00; C07D498/02; C07D498/10; C07D519/00; C08; C08K; C08K5/00; C08K5/0008; C08K5/005; C08K5/16; C08K5/34; C08K5/3412; C08K5/3432; C08K5/3435
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) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |