US3839137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corrugated film having increased stiffness
Assignee: EIDP Inc
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Filing: 1972-01-28
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Granted: 1974-10-01
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Expires: 1992-01-28
Abstract
Abstract Corrugated polymeric film can be stiffened in the direction transverse to corrugation lines by creating flattened, i.e., noncorrugated, narrow width lanes in that transverse direction.
Inventors
- 👤 R Davis
- 👤 T Dickerhofe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:31
CPC Classifications
H; H01; H01B; H01B7/00; H01B7/17; H01B7/18; H01B7/189; B; B29; B29C; B29C67/00; B29C67/0011; H01B7/02; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24628; Y10T428/24669; Y10T428/24694; Y10T428/24702
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
112 words
IN A CORRUGATED POLYMERIC FILM SELECTED FROM THE GROUP CONSISTING OF POLYPROPYLENE, THERMOPLASTIC POLYESTERS, HIGHDENSITY POLYETHYLENE, AND LAMINATES THEREOF, HAVING A THICKNESS BEFORE CORRUGATION OF 0.25 TO 3.5 MILS, 20 TO 40 CORRUGATIONS PER INCH, A CORRUGATION RATIO OF AT LEAST ABOUT 6, AND A TD STIFFNESS OF LESS THAN ABOUT 38 MG. AFTER CORRUGATION, THE IMPROVEMENT WHEREIN SAID FILM HAS A SERIES OF NONCORRUGATED LANES RUNNING TRANSVERSE TO THE DIRECTION OF THE LINES OF CORRUGATION, SAID LANES BEING ABOUT ONE THIRTY-SECOND TO ONE-EIGHT INCH IN WIDTH AND THERE BEING TWO TO SIX LANES PER INCH, SUCH THAT THE MODIFIED CORRUGATED FILM HAS A TD STIFFNESS BETWEEN ABOUT 50 TO 90 MG.
Claim 2
Dependent Claim
112 words
IN A CORRUGATED POLYMERIC FILM SELECTED FROM THE GROUP CONSISTING OF POLYPROPYLENE, THERMOPLASTIC POLYESTERS, HIGHDENSITY POLYETHYLENE, AND LAMINATES THEREOF, HAVING A THICKNESS BEFORE CORRUGATION OF 0.25 TO 3.5 MILS, 20 TO 40 CORRUGATIONS PER INCH, A CORRUGATION RATIO OF AT LEAST ABOUT 6, AND A TD STIFFNESS OF LESS THAN ABOUT 38 MG. AFTER CORRUGATION, THE IMPROVEMENT WHEREIN SAID FILM HAS A SERIES OF NONCORRUGATED LANES RUNNING TRANSVERSE TO THE DIRECTION OF THE LINES OF CORRUGATION, SAID LANES BEING ABOUT ONE THIRTY-SECOND TO ONE-EIGHT INCH IN WIDTH AND THERE BEING TWO TO SIX LANES PER INCH, SUCH THAT THE MODIFIED CORRUGATED FILM HAS A TD STIFFNESS BETWEEN ABOUT 50 TO 90 MG.
References Cited (Backward Citations)
US1189140A
Cited
US3025340A
Cited
US3105872A
Cited
US3244799A
Cited
US3518142A
Cited
US3614299A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-30 | 1978-04-01 | 1978-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-30 | 1982-04-01 | 1982-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-30 | 1986-04-01 | 1986-10-01 | $7700.00 | Window Closed / Lapsed |