US3489507A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter method and apparatus for removing hydrazine and derivatives of hydrazine
Assignee: American Optical Corp
•
Filing: 1967-12-01
•
Granted: 1970-01-13
•
Expires: 1987-12-01
Abstract
No abstract record available.
Inventors
- 👤 Wesley M Gardner
- 👤 William H Revoir
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:24
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/16; B01J20/18; B01J20/186; C; C01; C01B; C01B21/00; C01B21/082; C01B21/16; C07; C07C; C07C241/00; C07C241/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2930184A
Cited
GB825462A
Cited
US2992703A
Cited
US3318662A
Cited
US3165382A
Cited
US3345125A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-01-12 | 1973-07-14 | 1974-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-01-12 | 1977-07-14 | 1978-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-01-12 | 1981-07-14 | 1982-01-13 | $7700.00 | Window Closed / Lapsed |