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Patent US3528764A successfully refreshed from Google Patents.
US3528764A
Expired / Lapsed
US
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Method and apparatus for retarding evaporation from water surfaces
Assignee: Research Corp
•
Filing: 1967-11-28
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Granted: 1970-09-15
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Expires: 1987-11-28
Abstract
No abstract record available.
Inventors
- 👤 Castle O Reiser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:17
CPC Classifications
C; C02; C02F; C02F1/00; B; B01; B01J; B01J19/00; B01J19/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3127235A
Cited
US2563002A
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US2797140A
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US2878098A
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US3036880A
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US2903330A
Cited
GB898431A
Cited
US3184789A
Cited
US3199944A
Cited
US3425791A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-09-14 | 1974-03-16 | 1974-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-09-14 | 1978-03-16 | 1978-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-09-14 | 1982-03-16 | 1982-09-15 | $7700.00 | Window Closed / Lapsed |