US5296229A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible, elastic and biodegradable film made of polymer based on lactic acid, capable of being suitable especially for the production of medical dressings
Assignee: Solvay SA
•
Filing: 1992-07-20
•
Granted: 1994-03-22
•
Expires: 2012-07-20
Abstract
Abstract The film is obtained directly by extrusion from the lactic acid-based polymer plasticised beforehand by incorporation of 5 to 30% by weight of the polymer of a glycerol ester obtained from an acid containing 4 carbon atoms in its molecule. The film has an elongation at break of more than 300% and is particularly suitable for the production of medical dressings.
Inventors
- 👤 Dominique Grandjean
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:59
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/26; C08K; C08K5/00; C08K5/0008; C08K5/0016; C08K5/04; C08K5/10; C08K5/101; C08K5/103; C08L; C08L67/00; C08L67/04; C08J2367/00; C08J2367/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
74 words
A flexible, elastic and biodegradable film, wherein said film has less bubbles, less self-sticking and improved thermal stability, produced by extrusion of a copolymer of DL-lactic acid and glycolic acid, containing from 25 to 75 by weight of units derived from lactic acid, and said copolymer plasticised beforehand by incorporation of 5 to 30% by weight of the copolymer of a glycerol ester obtained from an acid containing 4 carbon atoms in its molecule.
Claim 2
Dependent Claim
74 words
A flexible, elastic and biodegradable film, wherein said film has less bubbles, less self-sticking and improved thermal stability, produced by extrusion of a copolymer of DL-lactic acid and glycolic acid, containing from 25 to 75 by weight of units derived from lactic acid, and said copolymer plasticised beforehand by incorporation of 5 to 30% by weight of the copolymer of a glycerol ester obtained from an acid containing 4 carbon atoms in its molecule.
Claim 3
Dependent Claim
18 words
Film according to claim 1, characterised in that it has an elongation at break of at least 300%.
Claim 4
Dependent Claim
13 words
Film according to claim 1, characterised in that the plasticiser is glycerol tributanoate.
Claim 5
Dependent Claim
31 words
Film according to claim 1, characterised in that the extruded DL-lactic acid and glycolic acid copolymer additionally contains from 1 to 30% by weight of the polymer of an alkylated cellulose.
Claim 6
Dependent Claim
24 words
Film according to claim 4, characterised in that the alkylated cellulose is chosen from the group consisting of hexapropyl cellulose and hexapropyl methyl cellulose.
Claim 7
Dependent Claim
14 words
Film according to claim 1, characterised in that is additionally contains a pharmaceutical product.
Claim 8
Dependent Claim
11 words
Medical dressing produced from a film obtained according to claim 1.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-03-21 | 1997-09-20 | 1998-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-03-21 | 2001-09-20 | 2002-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-03-21 | 2005-09-20 | 2006-03-22 | $7700.00 | Window Closed / Lapsed |