US3256379A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for stretching polyester films
Assignee: EIDP Inc
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Filing: 1961-11-21
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Granted: 1966-06-14
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Expires: 1981-11-21
Abstract
No abstract record available.
Inventors
- 👤 Heffelfinger Carl John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:15
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/02; B29C55/10; B29C55/12; B29C55/14; B29C55/146; B29K; B29K2067/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
THE PROCESS COMPRISING STRETCHING A SUBSTANTIALLY AMORPHOUS POLYMERIC LINEAR TEREPHTHALATE ESTER FILM AT A TEMPERATURE AT WHICH MOLECULAR ORIENTATION IS EFFECTED IN THE DIRECTION PERPENDICULAR TO EXTRUSION TO AN EXTENT OF AT LEAST 2.5 TIMES ITS INITIAL WIDTH AT A RATE OF SPEED OF AT LEAST 1,000 PERCENT PER MINUTE; AND THEREAFTER, STRETCHING SAID FILM AT A TEMPERATURE AT WHICH MOLECULAR ORIENTATION IS EFFECTED IN THE DIRECTION IN WHICH THE FILM IS EXTRUDED TO AN EXTENT OF AT LEAST 2.5 TIMES ITS LENGTH AT A RATE OF SPEED OF AT LEAST 60,000 PERCENT PER MINUTE.
Claim 2
Dependent Claim
95 words
THE PROCESS COMPRISING STRETCHING A SUBSTANTIALLY AMORPHOUS POLYMERIC LINEAR TEREPHTHALATE ESTER FILM AT A TEMPERATURE AT WHICH MOLECULAR ORIENTATION IS EFFECTED IN THE DIRECTION PERPENDICULAR TO EXTRUSION TO AN EXTENT OF AT LEAST 2.5 TIMES ITS INITIAL WIDTH AT A RATE OF SPEED OF AT LEAST 1,000 PERCENT PER MINUTE; AND THEREAFTER, STRETCHING SAID FILM AT A TEMPERATURE AT WHICH MOLECULAR ORIENTATION IS EFFECTED IN THE DIRECTION IN WHICH THE FILM IS EXTRUDED TO AN EXTENT OF AT LEAST 2.5 TIMES ITS LENGTH AT A RATE OF SPEED OF AT LEAST 60,000 PERCENT PER MINUTE.
References Cited (Backward Citations)
US2904841A
Cited
US2995779A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-06-13 | 1969-12-13 | 1970-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-06-13 | 1973-12-13 | 1974-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-06-13 | 1977-12-13 | 1978-06-14 | $7700.00 | Window Closed / Lapsed |