Patent US4729927A successfully refreshed from Google Patents.
US4729927A
Expired / Lapsed
US
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Polyester packaging material
Assignee: Teijin Ltd
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Filing: 1985-11-21
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Granted: 1988-03-08
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Expires: 2005-11-21
Abstract
Abstract A packaging polyester material comprising a polyethylene terephthalate component and a component of polyethylene isophthalate copolymerized with 5 to 60 mole % of an aliphatic hydroxycarboxylic acid having up to 8 carbon atoms. This packaging material is excellent in the resistance to the permeation of gases.
Inventors
- 👤 Masahiko Hirose
- 👤 Takatoshi Kuratsuji
- 👤 Toshihiro Santa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:42
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/36; B32B27/06; B32B27/08; C; C08; C08L; C08L67/00; C08L67/02; B32B2270/00; B32B2307/00; B32B2307/70; B32B2307/724; B32B2307/7242; B32B2553/00; Y; Y10; Y10S; Y10S428/00; Y10S428/911; Y10S525/00; Y10S525/933; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
77 words
A polyester packaging material having excellent resistance to the permeation of gases, said material comprised of a polyethylene terephthalate component and a component of polyethylene isophthalate copolymerized with 5 to 60 mole% of an aliphatic hydroxycarboxylic acid having up to 8 carbon atoms and wherein the copolymerized polyethylene isophthalate component is present in such an amount that the content of the units of the aliphatic hydroxycarboxylic acid is 3 to 25 mole% based on the total polyester.
Claim 2
Dependent Claim
77 words
A polyester packaging material having excellent resistance to the permeation of gases, said material comprised of a polyethylene terephthalate component and a component of polyethylene isophthalate copolymerized with 5 to 60 mole% of an aliphatic hydroxycarboxylic acid having up to 8 carbon atoms and wherein the copolymerized polyethylene isophthalate component is present in such an amount that the content of the units of the aliphatic hydroxycarboxylic acid is 3 to 25 mole% based on the total polyester.
Claim 3
Dependent Claim
26 words
A packaging material as set forth in claim 1, wherein the polyethylene terephthalate component and the copolymerized polyethylene isophthalate component are formed into a multi-layer structure.
Claim 4
Dependent Claim
28 words
A packaging material as set forth in claim 1, wherein the polyethylene terephthalate component and the copolymerized polyethylene isophthalate component are blended and formed into an integral structure.
Claim 5
Dependent Claim
30 words
A packaging material as set forth in claim 1, wherein the content of the units of the aliphatic hydroxycarboxylic acid is 5 to 20 mole% based on the total polyester.
Claim 6
Dependent Claim
35 words
A packaging material as set forth in claim 1, wherein the aliphatic hydroxycarboxylic acid is selected from glycolic acid, 3-hydroxypropionic acid, 4-hydroxybutyric acid, 5-hydroxyvaleric acid, 6-hydroxycaproic acid, 7-hydroxyenanthic acid, 8-hydroxycarprylic acid and functional derivatives thereof.
Claim 7
Dependent Claim
17 words
A packaging material as set forth in claim 5, wherein the aliphatic hydroxycarboxylic acid is glycolic acid.
Claim 8
Dependent Claim
23 words
A packaging material as set forth in claim 1, wherein the copolymerization ratio of the aliphatic hydroxycarboxylic acid is 10 to 50 mole%.
Claim 9
Dependent Claim
22 words
A packaging material as set forth in claim 1, wherein the intrinsic viscosity of the polyethylene terephthalate component is 0.5 to 1.5.
Claim 10
Dependent Claim
22 words
A packaging material as set forth in claim 1, wherein the intrinsic viscosity of the polyethylene isophthalate component is 0.3 to 1.5.
References Cited (Backward Citations)
GB1507876A
Cited
US4388456A
Cited
JPS5939547A
Cited
US4403090A
Cited
EP0105825A2
Cited
EP0105826A1
Cited
US4482586A
Cited
JPS59196316A
Cited
US4424242A
Cited
US4578437A
Cited
US4578295A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-08 | 1991-09-07 | 1992-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-08 | 1995-09-07 | 1996-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-08 | 1999-09-07 | 2000-03-08 | $7700.00 | Window Closed / Lapsed |