Patent US4070222A successfully refreshed from Google Patents.
US4070222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pretreatment of thermoplastic film for improved sealing
Assignee: Mobil Oil AS
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Filing: 1977-03-02
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Granted: 1978-01-24
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Expires: 1997-03-02
Abstract
Abstract A method is provided for the pretreatment of superposed layers of thermosplastic film which are to be heat sealed together, longitudinally, along a predetermined area. The film layers to be heat sealed are preheated utilizing heated air along a defined, continuous longitudinally extending area of the film layers. The preheated area is subsequently passed through a slit-seal device which simultaneously severs the preheated film layers and seals the severed edges together. The method is particularly useful for the slit-sealing of a continuously advancing flattened tube of thermoplastic which is characterized by having a non-uniform gauge in cross-section.
Inventors
- 👤 Robert H. Olson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:22
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B29; B29C; B29C65/00; B29C65/02; B29C65/10; B29C65/106; B29C65/74; B29C65/743; B29C65/7439; B29C65/745; B29C65/7459; B29C66/00; B29C66/01; B29C66/02; B29C66/024; B29C66/0242; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/40; B29C66/41; B29C66/43; B29C66/432; B29C66/4322; B29C66/70; B29C66/73; B29C66/739; B29C66/7392; B29C66/73921; B29C66/80; B29C66/83; B29C66/836; B29C66/84; B29C66/843; B29C66/8432; B29C66/90; B29C66/91; B29C66/914; B29C66/9141; B29C66/9161; B29C66/91641; B29C66/91643; B29C66/91645; B32B37/00; B32B37/06; B29C66/912; B29C66/9121; B29C66/91651; B29C66/91653; B29C66/91655; B29C66/93; B29C66/934; B29C66/93431; B29C66/939; B32B2307/00; B32B2307/30; B32B2307/31; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1054; Y10T156/12; Y10T156/1313
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
68 words
A method for slit-sealing a continuously advancing flattened tube of thermoplastic film which comprises sequentially: a. locally preheating said tube along at least one continuously extending longitudinally area utilizing heated air, said preheating being insufficient to cause said flattened tube to be heat welded together; and b. subsequently subsequently continuously slitting and sealing said flattened tube within said preheated longitudinal area thereby forming a plurality of individual tubes.
Claim 2
Independent Claim
68 words
A method for slit-sealing a continuously advancing flattened tube of thermoplastic film which comprises sequentially: a. locally preheating said tube along at least one continuously extending longitudinally area utilizing heated air, said preheating being insufficient to cause said flattened tube to be heat welded together; and b. subsequently subsequently continuously slitting and sealing said flattened tube within said preheated longitudinal area thereby forming a plurality of individual tubes.
Claim 3
Dependent Claim
23 words
A method in accordance with claim 1 wherein said flattened tube of thermoplastic film is characterized by having continuous, spaced-apart ribs formed therein.
Claim 4
Independent Claim
54 words
An apparatus for continuously preheating and subsequently slit-sealing a flattened tube of thermoplastic film comprising means for continuously advancing said tube, and hot air means for preheating below the sealing temperature of said tube along a defined longitudinal area and subsequently slit-sealing means for simultaneously dividing and sealing said tube in said preheated area.
Claim 5
Independent Claim
54 words
An apparatus for continuously preheating and subsequently slit-sealing a flattened tube of thermoplastic film comprising means for continuously advancing said tube, and hot air means for preheating below the sealing temperature of said tube along a defined longitudinal area and subsequently slit-sealing means for simultaneously dividing and sealing said tube in said preheated area.
Claim 6
Dependent Claim
22 words
An apparatus in accordance with claim 3 wherein said flattened tube of film is characterized by having continuous, spaced-apart, ribs formed therein.
References Cited (Backward Citations)
US2805700A
Cited
US2990875A
Cited
US3269278A
Cited
US3156010A
Cited
US3749635A
Cited
US3839126A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-23 | 1981-07-25 | 1982-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-23 | 1985-07-25 | 1986-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-23 | 1989-07-25 | 1990-01-24 | $7700.00 | Window Closed / Lapsed |