US5800911A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymeric sheet
Assignee: Imperial Chemical Industries Ltd
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Filing: 1997-03-19
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Granted: 1998-09-01
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Expires: 2017-03-19
Abstract
Abstract A composite sheet having a thickness in the range from 30 to 400 mu m, has an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, and a transparent crystalline polyester second layer. The first layer preferably contains titanium dioxide. The composite sheet is suitable for use as a replacement for aluminium foil, being particularly useful as a lid for a container.
Inventors
- 👤 Stephen William Sankey
- 👤 Mark Edward Dawes
- 👤 Paul David Lawrence
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:00
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/18; B32B27/36; B32B27/06; B32B27/08; B32B7/00; B32B7/04; B32B7/12; B29; B29K; B29K2995/00; B29K2995/0037; B29K2995/0081; B32B2307/00; B32B2307/40; B32B2307/41; B32B2307/412; B32B2307/70; B32B2307/704; B32B2307/718; B32B2307/72; B32B2309/00; B32B2309/02; B32B2309/022; B32B2309/08; B32B2309/10; B32B2309/105; C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08K2003/2237; C08K2003/2241; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/25; Y10T428/256; Y10T428/26; Y10T428/263; Y10T428/28; Y10T428/31504; Y10T428/31786; Y10T428/31797
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
95 words
A biaxially oriented composite sheet suitable for use in lidding, said sheet having a thickness in the range from 30 to 400 μm, said sheet consisting essentially of an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, and a transparent crystalline polyester second layer directly bonded to said first layer, said deformation index being measured at a temperature of 200° C. and under a pressure of 2 megaPascals and said biaxially oriented composite sheet having an ultimate tensile strength of from 14 to 26 Kg/mm 2 .
Claim 2
Dependent Claim
95 words
A biaxially oriented composite sheet suitable for use in lidding, said sheet having a thickness in the range from 30 to 400 μm, said sheet consisting essentially of an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, and a transparent crystalline polyester second layer directly bonded to said first layer, said deformation index being measured at a temperature of 200° C. and under a pressure of 2 megaPascals and said biaxially oriented composite sheet having an ultimate tensile strength of from 14 to 26 Kg/mm 2 .
Claim 3
Dependent Claim
23 words
A composite sheet according to claim 1 wherein the first layer has a Transmission Optical Density in the range from 0.4 to 1.75.
Claim 4
Dependent Claim
29 words
A composite sheet according to claim 1 wherein the first layer contains from 1 to 30% by weight titanium dioxide based on the weight of the first layer polyester.
Claim 5
Dependent Claim
38 words
A composite sheet according to claim 3 wherein the titanium dioxide is present in the first layer at a concentration within the range from 5% to 20% by weight, based on the weight of the first layer polyester.
Claim 6
Dependent Claim
26 words
A composite sheet according to claim 3 wherein the titanium dioxide has a volume distributed median particle diameter in the range from 0.2 to 0.9 μm.
Claim 7
Dependent Claim
26 words
A composite sheet according to claim 1 wherein the ratio of the thickness of the first layer/second layer is in the range from 3 to 25:1.
Claim 8
Dependent Claim
19 words
A composite sheet according to claim 1 wherein both the first layer and second layer comprise the same polyester.
Claim 9
Dependent Claim
35 words
A composite sheet according to claim 1 wherein at least one of the first layer and second layer has on a surface thereof remote from the other layer, an adherent layer comprising an acrylic resin.
Claim 10
Dependent Claim
19 words
A composite sheet according to claim 1 wherein the second layer ranges in thickness from 1 to 100 μm.
Claim 11
Dependent Claim
37 words
A composite sheet according to claim 1 wherein the second layer ranges in thickness from 1 to 100 μm and the of the thickness of the first layer/second layer is in the range of 2 to 50:1.
Claim 12
Dependent Claim
104 words
A biaxially oriented composite sheet having a thickness in the range from 30 to 400 μm, said sheet being suitable for lidding and consisting essentially of an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, in direct contact with a transparent crystalline polyester second layer, said deformation index measured at a temperature of 200° C. and under a pressure of 2 megaPascals, said layers being co-extruded and said composite sheet having an ultimate tensile strength in the range of from 14 to 26 Kgmm -2 and being further characterized by its opacity, tear resistance and embossibility.
Claim 13
Dependent Claim
104 words
A biaxially oriented composite sheet having a thickness in the range from 30 to 400 μm, said sheet being suitable for lidding and consisting essentially of an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, in direct contact with a transparent crystalline polyester second layer, said deformation index measured at a temperature of 200° C. and under a pressure of 2 megaPascals, said layers being co-extruded and said composite sheet having an ultimate tensile strength in the range of from 14 to 26 Kgmm -2 and being further characterized by its opacity, tear resistance and embossibility.
Claim 14
Dependent Claim
16 words
A lid for a container consisting essentially of a biaxially oriented composite sheet of claim 11.
Claim 15
Independent Claim
95 words
A method for producing a biaxially oriented composite sheet having a thickness in the range from 30 to 400 μm, comprising forming an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, bonding on a surface thereof a transparent crystalline polyester second layer and then biaxially orienting each of said layers, said deformation index being measured at a temperature of 200° C. and under a pressure of 2 megaPascals and said biaxially oriented composite sheet having an ultimate tensile strength of from 14 to 26 Kg/mm 2 .
Claim 16
Independent Claim
95 words
A method for producing a biaxially oriented composite sheet having a thickness in the range from 30 to 400 μm, comprising forming an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, bonding on a surface thereof a transparent crystalline polyester second layer and then biaxially orienting each of said layers, said deformation index being measured at a temperature of 200° C. and under a pressure of 2 megaPascals and said biaxially oriented composite sheet having an ultimate tensile strength of from 14 to 26 Kg/mm 2 .
Claim 17
Dependent Claim
14 words
The method of claim 13 wherein the layers are co-extruded simultaneously and biaxially oriented.
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FR2207804A1
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GB1487414A
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EP0053498A2
Cited
EP0199228A2
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US4927675A
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US4880700A
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EP0312226A1
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EP0360201A2
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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) | 2001-08-31 | 2002-03-02 | 2002-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-08-31 | 2006-03-02 | 2006-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-08-31 | 2010-03-02 | 2010-09-01 | $7700.00 | Window Closed / Lapsed |