Patent US2328644A successfully refreshed from Google Patents.
US2328644A
Expired / Lapsed
US
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Heat insulating material
Assignee: HERMAN A SPERLICH
•
Filing: 1941-01-25
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Granted: 1943-09-07
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Expires: 1961-01-25
Abstract
No abstract record available.
Inventors
- 👤 Arthur H Happe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:44
CPC Classifications
C; C04; C04B; C04B32/00; C04B32/005; Y; Y10; Y10S; Y10S106/00; Y10S106/03
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) | 1946-09-06 | 1947-03-08 | 1947-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1950-09-06 | 1951-03-08 | 1951-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1954-09-06 | 1955-03-08 | 1955-09-07 | $7700.00 | Window Closed / Lapsed |