US3584656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of polymeric tubular films
Assignee: ALGEMENE KUNSTZIJ DE UNIE NV
•
Filing: 1969-02-14
•
Granted: 1971-06-15
•
Expires: 1989-02-14
Abstract
Abstract A polymeric tubular film comprising a film wall made up of at least three polymeric layers which are alternately formed of different compound polymers and which at least partially have a spiralling shape. At least one of the inner and outer surfaces of the wall is formed by a single substantially homogeneous onepolymer layer. Also a process and an apparatus for the manufacture of such film are disclosed.
Inventors
- 👤 Leendert Van Assendelet
- 👤 Bertus H Zandstra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:31
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/32; B29C48/34; B29C48/03; B29C48/09; B29C48/10; B29C48/16; B29C48/18; B29C48/21; B29C48/33; B29C48/335
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
22 words
The tubular film of claim 1 in which the outer surface of the wall is formed by a single homogeneous one-polymer layer.
Claim 2
Dependent Claim
22 words
The tubular film of claim 1 in which the inner surface of the wall is formed by a single homogeneous one-polymer layer.
Claim 3
Dependent Claim
26 words
The tubular film of claim 1 in which the inner and the outer surface of the wall are each formed by a single homogeneous one-polymer layer.
Claim 4
Dependent Claim
23 words
The tubular film of claim 4 in which the homogeneous inner and outer surfaces of the film consist of the same component polymer.
Claim 5
Dependent Claim
43 words
The tubular film of claim 1 in which at least one of the two surfaces of the wall is formed by a homogeneous layer having a thickness in the radial direction that is different from that of any one of the spiralling layers.
Claim 6
Dependent Claim
24 words
The tubular film of claim 6 in which said homogeneous layer is at least 50 percent thicker than any one of the spiralling layers.
Claim 7
Dependent Claim
24 words
The tubular film of claim 7 in which said homogeneous layer is at least 50 percent thinner than any one of the spiralling layers.
Claim 8
Dependent Claim
22 words
The tubular film of claim 4 in which the inner surface and the outer surface of the wall are different component polymers.
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) | 1974-06-14 | 1974-12-14 | 1975-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-14 | 1978-12-14 | 1979-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-14 | 1982-12-14 | 1983-06-15 | $7700.00 | Window Closed / Lapsed |