Patent US3635890A successfully refreshed from Google Patents.
US3635890A
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Stabilization of polyphenylene oxides
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1970-09-08
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Granted: 1972-01-18
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Expires: 1990-09-08
Abstract
Abstract POLYPHENYLENE OXIDES ARE STABILIZED TO THERMAL OXIDATION BY REACTING THE POLYMERS WITH A HALOGENATED PHOSPHORUS COMPOUND IN THE PRESENCE OR ABSENCE OF A BASIC COMPOUND.
Inventors
- 👤 Toshio Takemura
- 👤 Isamu Nakagawa
- 👤 Seizo Nakashio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:14
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/34; C08G65/48; C08G65/485; C08K; C08K5/00; C08K5/49
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) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |