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US2668328A
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US
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Method of casting patterned plastic sheets
Assignee: U S Chemical Co
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Filing: 1953-04-08
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Granted: 1954-02-09
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Expires: 1973-04-08
Abstract
No abstract record available.
Inventors
- 👤 Frank E Porter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:59
CPC Classifications
B; B29; B29C; B29C39/00; B29C39/003; B29C39/006
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-08 | 1957-08-10 | 1958-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-08 | 1961-08-10 | 1962-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-08 | 1965-08-10 | 1966-02-09 | $7700.00 | Window Closed / Lapsed |