US5397640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biaxially oriented heat-shrinkable film
Assignee: Curwood Inc
•
Filing: 1994-01-31
•
Granted: 1995-03-14
•
Expires: 2014-01-31
Abstract
Abstract An improved biaxially oriented heat-shrinkable film of the type used for packaging food, such as poultry, processed meat, and fresh meat.
Inventors
- 👤 Paul N. Georgelos
- 👤 James E. Pelkie
- 👤 Darrel L. Wilhoit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:34
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B32; B32B; B32B27/00; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; C08L23/0846; C08L23/0853; C08J2323/00; C08J2323/02; C08J2323/04; C08L2205/00; C08L2205/02; C08L2205/03; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
100 words
A biaxially oriented heat-shrinkable film comprising a three component blend of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm 3 and having a melting point between about 55° C. and about 85° C. as major components, wherein said VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. % with a vinyl acetate content of less than about 18 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
Claim 2
Dependent Claim
100 words
A biaxially oriented heat-shrinkable film comprising a three component blend of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm 3 and having a melting point between about 55° C. and about 85° C. as major components, wherein said VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. % with a vinyl acetate content of less than about 18 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
Claim 3
Dependent Claim
15 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein, said film is a monolayer.
Claim 4
Dependent Claim
21 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said blend comprises at least one layer of a multilayer film.
Claim 5
Dependent Claim
22 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said VLDPE has a melting point of at least about 115° C.
Claim 6
Dependent Claim
24 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said EVA has a vinyl acetate content of less than about 15 wt. %.
Claim 7
Dependent Claim
26 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said VLDPE comprises between about 25 and about 30 wt. % of said three component blend.
Claim 8
Dependent Claim
26 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said EVA comprises between about 33 and about 38 wt. % of said three component blend.
Claim 9
Dependent Claim
26 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said plastomer comprises between about 33 and about 38 wt. % of said three component blend.
Claim 10
Dependent Claim
49 words
A biaxially oriented heat-shrinkable film according to claim 1 wherein said VLDPE comprises between about 25 and about 30 wt. %, said EVA comprises between about 33 and about 38 wt. %, and said plastomer comprises between about 33 and about 38 wt. % of said three component blend.
Claim 11
Dependent Claim
50 words
A biaxially oriented heat-shrinkable film according to claim 3 wherein said multilayer film comprises at least three layers including an oxygen barrier core layer between a first outer layer and a second outer layer, and said three component blend comprises at least one of said first and second outer layers.
Claim 12
Dependent Claim
47 words
A biaxially oriented heat-shrinkable film according to claim 3 wherein said multilayer film comprises three layers including an oxygen barrier core layer between a first outer layer and a second outer layer, and said first and second outer layers each comprise an identical said three component blend.
Claim 13
Dependent Claim
12 words
A biaxially oriented heat-shrinkable film according to claim 1 which is irradiated.
Claim 14
Dependent Claim
12 words
A biaxially oriented heat-shrinkable film according to claim 11 which is irradiated.
Claim 15
Dependent Claim
54 words
An irradiated biaxially oriented heat-shrinkable film according to claim 1 which has at least about 50% shrink in both the machine and transverse directions at 90° C., haze of less than about 6%, gloss of at least about 77 Hunter Units and hot water seal strength of at least 15 seconds at 95° C.
Claim 16
Dependent Claim
124 words
In a method for manufacturing a biaxially oriented heat-shrinkable film wherein a primary tube is extruded, cooled, reheated and stretched in the machine direction and inflated in the transverse direction by internal gas to form a bubble, then collapsed and withdrawn as biaxially oriented thinner film: the improvement comprising forming the primary tube from a three component blend of major constituents consisting of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm 3 wherein the VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
Claim 17
Dependent Claim
124 words
In a method for manufacturing a biaxially oriented heat-shrinkable film wherein a primary tube is extruded, cooled, reheated and stretched in the machine direction and inflated in the transverse direction by internal gas to form a bubble, then collapsed and withdrawn as biaxially oriented thinner film: the improvement comprising forming the primary tube from a three component blend of major constituents consisting of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm 3 wherein the VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
Claim 18
Dependent Claim
79 words
An irradiated biaxially oriented heat-shrinkable bag formed from film comprising a three component blend of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm 3 as major components, wherein said VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
Claim 19
Dependent Claim
79 words
An irradiated biaxially oriented heat-shrinkable bag formed from film comprising a three component blend of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm 3 as major components, wherein said VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
References Cited (Backward Citations)
US4952451A
Cited
EP0436196A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-03-13 | 1998-09-12 | 1999-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-13 | 2002-09-12 | 2003-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-13 | 2006-09-12 | 2007-03-14 | $7700.00 | Window Closed / Lapsed |