US2586820A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyethylene film manufacture
Assignee: Union Carbide Corp
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Filing: 1948-06-26
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Granted: 1952-02-26
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Expires: 1968-06-26
Abstract
No abstract record available.
Inventors
- 👤 William F Hemperly
- 👤 Nelson R Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:22
CPC Classifications
B; B29; B29C; B29C43/00; B29C43/22; B29C43/24; B29C55/00; B29C55/02; B29C55/04; B29C55/06; C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
105 words
PROCESS FOR PRODUCING PLASTIC FILM FROM A NORMALLY SOLID POLYMER OF ETHYLENE CONTAINING A SMALL AMOUNT OF A RELEASE AGENT WHICH COMPRISES THE STEPS OF CALENDERING A NORMALLY SOLID ETHYLENE POLYMER AT A TEMPERATURE ABOVE ITS SOFTENING POINT, FORMING ON THE CALENDER''S TAKE-OFF ROLL A SHEET OF THE POLYMER, REMOVING THE SHEET FROM SAID ROLL WHILE SAID SHEET IS AT A TEMPERATURE ABOVE ITS SOFTENING TEMPERATURE, LONGITUDINALLY STRETCHING THE REMOVED SHEET TO REDUCE ITS THICKNESS WHILE IT IS MAINTAINED AT ABOVE ITS SOFTENING TEMPERATURE, AND THEN IMMEDIATELY CHILLING THE STRETCHED SHEET TO A TEMPERATURE LESS THAN 80* C. WHILE MAINTAINING SAID TENSION ON SAID SHEET.
Claim 2
Dependent Claim
105 words
PROCESS FOR PRODUCING PLASTIC FILM FROM A NORMALLY SOLID POLYMER OF ETHYLENE CONTAINING A SMALL AMOUNT OF A RELEASE AGENT WHICH COMPRISES THE STEPS OF CALENDERING A NORMALLY SOLID ETHYLENE POLYMER AT A TEMPERATURE ABOVE ITS SOFTENING POINT, FORMING ON THE CALENDER''S TAKE-OFF ROLL A SHEET OF THE POLYMER, REMOVING THE SHEET FROM SAID ROLL WHILE SAID SHEET IS AT A TEMPERATURE ABOVE ITS SOFTENING TEMPERATURE, LONGITUDINALLY STRETCHING THE REMOVED SHEET TO REDUCE ITS THICKNESS WHILE IT IS MAINTAINED AT ABOVE ITS SOFTENING TEMPERATURE, AND THEN IMMEDIATELY CHILLING THE STRETCHED SHEET TO A TEMPERATURE LESS THAN 80* C. WHILE MAINTAINING SAID TENSION ON SAID SHEET.
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) | 1955-02-25 | 1955-08-27 | 1956-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-02-25 | 1959-08-27 | 1960-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-02-25 | 1963-08-27 | 1964-02-26 | $7700.00 | Window Closed / Lapsed |