US3324218A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of polypropylene films
Assignee: Kalle GmbH and Co KG
•
Filing: 1964-09-25
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Granted: 1967-06-06
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Expires: 1984-09-25
Abstract
No abstract record available.
Inventors
- 👤 Gebler Horst
- 👤 Seifried Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:50
CPC Classifications
B; B29; B29C; B29C55/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
144 words
A PROCESS FOR THE MANUFACTURE OF SHRINKABLE POLYPROPYLENE FILMS WHICH COMPRISES EXTRUDING PREDOMINATELY ISOTACTIC POLYPROPYLENE AT A TEMPERATURE IN THE RANGE OF ABOUT 190 TO 325*C. THROUGH A SHEET DIE HAVING A WIDTH SUCH AS TO GIVE THE RESULSTING FILM A THICKNESS GREATER THAN 0.3 MM., QUENCHING THE EXTRUDED MELT AT A TEMPERATURE BELOW 90%C., PRE-HEATING THE FILM FOR LONGITUDINAL STRETCHING TOA TEMPERATURE IN THE RANGE OF (TI-5* C.) TO T1 (T1=130 TO 140*C.), FURTHER HEATING THE FILM IN CONTACT WITH A ROLL MAINTAINED AT A TEMPERATURE T2 (T2=140 TO 150*C.), STRETCHING THE FILM TO 5 TO 7 TIMES ITS ORIGINAL LENGTH, COOLING THE FILM, HEATING THE FILM TO A TEMPERATURE IN THE RANGE OF (T3-5*C.) TO T3 (T3=155 TO 165*C.), AND STRETCHING THE FILM TO 8 TO 13 TIMES ITS WIDTH AT AN AMBIENT TEMPERATURE OF T4 (T4=150 TO 160* C.), WHERE T1<T2<T4<T3.
Claim 2
Dependent Claim
144 words
A PROCESS FOR THE MANUFACTURE OF SHRINKABLE POLYPROPYLENE FILMS WHICH COMPRISES EXTRUDING PREDOMINATELY ISOTACTIC POLYPROPYLENE AT A TEMPERATURE IN THE RANGE OF ABOUT 190 TO 325*C. THROUGH A SHEET DIE HAVING A WIDTH SUCH AS TO GIVE THE RESULSTING FILM A THICKNESS GREATER THAN 0.3 MM., QUENCHING THE EXTRUDED MELT AT A TEMPERATURE BELOW 90%C., PRE-HEATING THE FILM FOR LONGITUDINAL STRETCHING TOA TEMPERATURE IN THE RANGE OF (TI-5* C.) TO T1 (T1=130 TO 140*C.), FURTHER HEATING THE FILM IN CONTACT WITH A ROLL MAINTAINED AT A TEMPERATURE T2 (T2=140 TO 150*C.), STRETCHING THE FILM TO 5 TO 7 TIMES ITS ORIGINAL LENGTH, COOLING THE FILM, HEATING THE FILM TO A TEMPERATURE IN THE RANGE OF (T3-5*C.) TO T3 (T3=155 TO 165*C.), AND STRETCHING THE FILM TO 8 TO 13 TIMES ITS WIDTH AT AN AMBIENT TEMPERATURE OF T4 (T4=150 TO 160* C.), WHERE T1<T2<T4<T3.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-06-05 | 1970-12-05 | 1971-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-06-05 | 1974-12-05 | 1975-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-06-05 | 1978-12-05 | 1979-06-06 | $7700.00 | Window Closed / Lapsed |