US3597515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plastic extrusion process in chill roll casting of film for improved flatness
Assignee: Dow Chemical Co
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Filing: 1969-01-22
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Granted: 1971-08-03
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Expires: 1989-01-22
Abstract
Abstract IN CHILL ROLLING RASTING OF PLASTIC FILM, IMPROVED FLATNESS IS OBTAINED BY OSCILLATING THE INTENSITY OF A FLAT STREAM OF GAS WHICH IS APPLIED TRANSVERSE TO THE DIRECTION OF ECTRUSION. BY ADJUSTMENT OF THE AIR STREAM, THICK OR THIN SPOTS MAY BE REDUCED AND DISTRIBUTED ACROSS THE FILM.
Inventors
- 👤 Almar T Widiger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:18
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/911; B29C48/9135; B29C48/915; B29C48/917; B29C48/03; B29C48/07; B29C48/08; B29C48/914
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) | 1974-08-02 | 1975-02-01 | 1975-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-02 | 1979-02-01 | 1979-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-02 | 1983-02-01 | 1983-08-03 | $7700.00 | Window Closed / Lapsed |