US4463153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat shrinkable film and process for preparing the same
Assignee: Kohjin Holdings Co Ltd
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Filing: 1982-02-19
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Granted: 1984-07-31
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Expires: 2002-02-19
Abstract
Abstract A process for simultaneously, biaxially orienting tubular ethylene polymer film by expansion and extension of the tube under particular conditions for heating the expanding tube, to give a heat skrinkable film. The heat shrinkable film has excellent heat shrinkability, shrinkage stress, transparency, heat sealability and impact resistance, and is very suited for use in shrink packaging.
Inventors
- 👤 Tomoji Mizutani
- 👤 Hitoshi Fukushima
- 👤 Yoshihiro Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:09
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B29; B29C; B29C55/00; B29C55/02; B29C55/10; B29C55/12; B29C55/16; B29C61/00; B29C61/003; B29C61/06; B29C61/08; B29K; B29K2023/00; B29K2023/04; B29K2023/06; C08J2323/00; C08J2323/02; C08J2323/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
112 words
A heat shrinkable film which is a biaxially stretched film of a non-crosslinked ethylene polymer and which has a heat shrinkage percent of not less than 25% and a heat shrinkage stress of not less than 12 kg./cm. 2 , respectively at a temperature of 15° C. below the melting point of the ethylene polymer and has a bar heat seal strength of not less than 900 g./10 mm. in width and an impact strength of beads sealed portion of not less than about 5 kg.cm., said ethylene polymer being a copolymer of ethylene and an α-olefinically unsaturated monomer and having a density of 0.91 to 0.93 g./cm. 3 at 25° C.
Claim 2
Dependent Claim
112 words
A heat shrinkable film which is a biaxially stretched film of a non-crosslinked ethylene polymer and which has a heat shrinkage percent of not less than 25% and a heat shrinkage stress of not less than 12 kg./cm. 2 , respectively at a temperature of 15° C. below the melting point of the ethylene polymer and has a bar heat seal strength of not less than 900 g./10 mm. in width and an impact strength of beads sealed portion of not less than about 5 kg.cm., said ethylene polymer being a copolymer of ethylene and an α-olefinically unsaturated monomer and having a density of 0.91 to 0.93 g./cm. 3 at 25° C.
Claim 3
Dependent Claim
64 words
The heat shrinkable film of claim 1, which is a stretched film of an ethylene polymer having a density of 0.91 to 0.93 g./cm. 3 at 25° C., a non-stretched film made of said ethylene polymer having a tensile strength at 300% elongation of not less than 15 kg./cm. 2 at a temperature of 15° C. below the melting point of said ethylene polymer.
Claim 4
Dependent Claim
32 words
The heat shrinkable film of claim 1, wherein said ethylene polymer is a copolymer of ethylene and not more than 25% by weight of an α-olefin having 3 to 12 carbon atoms.
Claim 5
Dependent Claim
32 words
The heat shrinkable film of claim 1, wherein said ethylene polymer is a copolymer of ethylene and not more than 15% by weight of an α-olefin having 4 to 6 carbon atoms.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-31 | 1988-01-30 | 1988-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-31 | 1992-01-30 | 1992-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-31 | 1996-01-30 | 1996-07-31 | $7700.00 | Window Closed / Lapsed |