Embossed film
Abstract
Abstract EMBOSSED, BIAXIALLY ORIENTED PROPYLENE POLYMER FILMS HAVING GREAT TEAR STRENGTH FOR THEIR THICKNESS CAN BE PREPARED IF CERTAIN CRITICAL LIMITATIONS ARE FOLLOWED. THE PROCESS COMPRISES EMBOSSING A SHEET OF PROPYLENE POLYMER HAVING A CRYSTALLINITY OF FROM ABOUT 40% TO 65% AND CONTAINING AT LEAST 80% OF REPEATING UNITS DERIVED FROM PROPYLENE MONOMER TO A DEPTH OF FROM ABOUT 50% TO 75% OF ITS THICKNESS WITH AT LEAST 4 BUT NO MORE THAN 600 UNIFORM RAISED BOSSES PER SQUARE INCH, EACH BOSS ENCLOSED BY A RAISED LIP, THE VALLEY AREAS SEPARATING INDIVIDUAL BOSSES CONSTITUTING FROM ABOUT 20% TO 40% OF THE SURFACE OF THE EMBOSSED FILM AND SUBJECTING THE THUS EMBOSSED FILM TO BIAXIAL DRAWING OF AT LEAST 2.5 TO 5.0 TIMES IN BOTH THE MACHINE AND CROSS-MACHINE DIRECTIONS.
Inventors
- 👤 C Liu
Bibliographic Details
Claims Analysis
Total Claims: 0References 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) | 1977-08-26 | 1978-02-25 | 1978-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-26 | 1982-02-25 | 1982-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-26 | 1986-02-25 | 1986-08-27 | $7700.00 | Window Closed / Lapsed |