US5783271A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biodegradable alipathic polyster, melt-extrusion film thereof, and process for the production thereof
Assignee: Tokuyama Corp
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Filing: 1996-04-24
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Granted: 1998-07-21
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Expires: 2016-04-24
Abstract
Abstract A process for the production of biodegradable aliphatic polyester particles by (co)polymerizing 2-oxetanone or a mixture containing at least 80% by weight of 2-oxetanone and up to 20% by weight of a cyclic ester or cyclic ether other than 2-oxetanone in the presence of a polymerization initiator supported on a carrier in which an ion polymerization initiator is supported on poly(2-oxetanone) in a liquid medium having a solubility parameter of about 15 to about 18 MPa+E,fra 1/2+EE and being capable of dissolving 2-oxetanone, and in a polymerizing apparatus having an internal surface formed of a material which is free of polarity or whose polarity is very small, to form a particulate aliphatic polyester; and a biodegradable aliphatic polyester melt-extrusion film, which comprises the biodegradable aliphatic polyester having a weight average molecular weight of 20,000 to 2,000,000, and having a water vapor transmission rate of 300 to 700 g/m2x24 hoursx25 mu m and heat-fusing strength of 500 to 5,000 gf/15 mm.
Inventors
- 👤 Haruo Nishida
- 👤 Mitsuhiro Yamashita
- 👤 Norikazu Hattori
- 👤 Yoshiki Ochi
- 👤 Tetsuo Kuwaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:42
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08G; C08G63/00; C08G63/02; C08G63/06; C08G63/08; C08G63/78; C08G63/82; C08G63/823; C08J2367/00; C08J2367/04; Y; Y10; Y10S; Y10S220/00; Y10S220/30; Y10T; Y10T428/00; Y10T428/13; Y10T428/1334; Y10T428/1345; Y10T428/1352; Y10T428/1355; Y10T428/29; Y10T428/2982
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
81 words
A biodegradable bag formed of a biodegradable aliphatic polyester melt-extrusion film comprising a biodegradable aliphatic polyester containing a recurring unit of the formula (1) ##STR4## as a main recurring unit and having a weight average molecular weight of 20,000 to 2,000,000 and which has a water vapor transmission rate of 300 to 700 g/m 2 ·24 hours·25 μm and heat fusing strength of 500 to 5,000 gf/15 mm; at least part of the film being heat-fusion bonded to form a bag.
Claim 2
Dependent Claim
81 words
A biodegradable bag formed of a biodegradable aliphatic polyester melt-extrusion film comprising a biodegradable aliphatic polyester containing a recurring unit of the formula (1) ##STR4## as a main recurring unit and having a weight average molecular weight of 20,000 to 2,000,000 and which has a water vapor transmission rate of 300 to 700 g/m 2 ·24 hours·25 μm and heat fusing strength of 500 to 5,000 gf/15 mm; at least part of the film being heat-fusion bonded to form a bag.
Claim 3
Dependent Claim
85 words
A biodegradable bag formed of a biodegradable aliphatic polyester melt-extrusion film comprising: a biodegradable aliphatic polyester containing a recurring unit of the formula (1) ##STR5## as a main recurring unit and having a weight average molecular weight of 20,000 to 2,000,000 and which has a water vapor transmission rate of 300 to 700 g/m 2 ·24 hours·25 μm and heat fusing strength of 500 to 5,000 gf/15 mm, and an inorganic filler at least part of the film being heat-fusion bonded to form a bag.
Claim 4
Dependent Claim
85 words
A biodegradable bag formed of a biodegradable aliphatic polyester melt-extrusion film comprising: a biodegradable aliphatic polyester containing a recurring unit of the formula (1) ##STR5## as a main recurring unit and having a weight average molecular weight of 20,000 to 2,000,000 and which has a water vapor transmission rate of 300 to 700 g/m 2 ·24 hours·25 μm and heat fusing strength of 500 to 5,000 gf/15 mm, and an inorganic filler at least part of the film being heat-fusion bonded to form a bag.
Claim 5
Dependent Claim
83 words
Biodegradable aliphatic polyester particles excellent in handling properties, (a) which comprises a biodegradable aliphatic polyester containing a recurring unit of the formula (1), ##STR6## as a main recurring unit and having a weight average molecular weight of 20,000 to 2,000,000, (b) of which at least 70% by weight is present in the particle diameter range of 150 μm to 3 mm in a particle size distribution histogram, and (c) which has a bulk specific gravity in the range of 0.3 to 0.6 g/ml.
Claim 6
Dependent Claim
83 words
Biodegradable aliphatic polyester particles excellent in handling properties, (a) which comprises a biodegradable aliphatic polyester containing a recurring unit of the formula (1), ##STR6## as a main recurring unit and having a weight average molecular weight of 20,000 to 2,000,000, (b) of which at least 70% by weight is present in the particle diameter range of 150 μm to 3 mm in a particle size distribution histogram, and (c) which has a bulk specific gravity in the range of 0.3 to 0.6 g/ml.
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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) | 2001-07-20 | 2002-01-19 | 2002-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-07-20 | 2006-01-19 | 2006-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-07-20 | 2010-01-19 | 2010-07-21 | $7700.00 | Window Closed / Lapsed |