US5035893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wound covering
Assignee: Mitsubishi Chemical Corp
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Filing: 1989-11-22
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Granted: 1991-07-30
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Expires: 2009-11-22
Abstract
Abstract The present invention relates to a wound covering comprising a sheet of biopolymeric material and a film of a polyurethane resin obtained by reacting a diisocyanate and a random copolymer of tetrahydrofuran and ethylene oxide to produce a urethane prepolymer, and extending the molecular chain of said prepolymer by using a chain extender, said random copolymer containing 20 to 80% by weight of the ethylene oxide unit in the molecular chain thereof and having a number-average molecular weight of 800 to 3000. The wound covering of the present invention is excellent in adhesion flexibility, durability, easy handling, preservation, sterile filtration, compatibility with cell, blood starching, water-vapor permeability. Therefore, it is quite suitable for practical use.
Inventors
- 👤 Nobuyuki Shioya
- 👤 Yoshimitsu Kuroyanagi
- 👤 Yasuo Kounami
- 👤 Tatsuhiko Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:18
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C08G18/4854; A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/26; A61L15/28; A61L15/32; A61L15/325; A61L15/42; A61L15/44; A61L15/46
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
120 words
A laminate wound covering comprising a sheet of biopolymeric material selected from the group consisting of collagen, gelatin, alginic acid, chitin, chitosan, fibrin, dextran and polyamino acids, for contacting said wound and a film of a polyurethane resin in contact with said biopolymeric material sheet having a water-vapor permeability of 2,000 g/m 2 ·24 hrs. or more which is obtained by reacting a diisocyanate and a random copolymer of tetrahydrofuran and ethylene oxide to produce a urethane prepolymer, and extending the molecular chain of said prepolymer by using a chain extender, said random copolymer having 20 to 80% by weight of the ethylene oxide unit in the molecular chain thereof and having a number-average molecular weight of 800 to 3000.
Claim 2
Dependent Claim
120 words
A laminate wound covering comprising a sheet of biopolymeric material selected from the group consisting of collagen, gelatin, alginic acid, chitin, chitosan, fibrin, dextran and polyamino acids, for contacting said wound and a film of a polyurethane resin in contact with said biopolymeric material sheet having a water-vapor permeability of 2,000 g/m 2 ·24 hrs. or more which is obtained by reacting a diisocyanate and a random copolymer of tetrahydrofuran and ethylene oxide to produce a urethane prepolymer, and extending the molecular chain of said prepolymer by using a chain extender, said random copolymer having 20 to 80% by weight of the ethylene oxide unit in the molecular chain thereof and having a number-average molecular weight of 800 to 3000.
Claim 3
Dependent Claim
22 words
A wound covering according to claim 1, wherein said polyurethane film or said sheet of a biopolymeric material contains an antibacterial agent.
Claim 4
Dependent Claim
27 words
A wound covering according to claim 1, wherein said random copolymer has 30 to 70% by weight of the ethylene oxide unit in the molecular chain thereof.
Claim 5
Dependent Claim
20 words
A wound covering according to claim 1, wherein said number-average molecular weight of said random copolymer is 1000 to 2500.
Claim 6
Dependent Claim
13 words
A wound covering according to claim 1, wherein said diisocyanate is alicyclic diisocyanate.
Claim 7
Dependent Claim
30 words
A wound covering according to claim 5, wherein said alicyclic diisocyanate is a member selected from the group consisting of isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexylene diisocyanate, and hydrogenated tolylene diisocyanates.
Claim 8
Dependent Claim
14 words
A wound covering according to claim 6, wherein said alicyclic diisocyanate is 4,4-dicyclohexylmethane diisocyanate.
Claim 9
Dependent Claim
14 words
A wound covering according to claim 1, wherein said chain extender is alicyclic diamine.
Claim 10
Dependent Claim
29 words
A wound covering according to claim 8, wherein said alicyclic diamine is a member selected from the group consisting of isophorone diamine, 4,4'-dicyclohexylmethane diamine, 3,3'-dimethyl-4,4'-dicyclohexylmethane diamine, and 1,4-cyclohexylene diamine.
Claim 11
Dependent Claim
14 words
A wound covering according to claim 9, wherein said alicyclic diamine is isophorone diamine.
Claim 12
Dependent Claim
19 words
A wound covering according to claim 1, wherein the thickness of said polyurethane film is 10 to 80 μm.
Claim 13
Dependent Claim
21 words
A wound covering according to claim 1, wherein 100% modulus of said polyurethane film is 20 kg/cm 2 to 80 kg/cm.
Claim 14
Dependent Claim
45 words
A wound covering according to claim 1, wherein the thickness of said polyurethane film is 10 to 80 μm, water-vapor permeability of said film is 2,000g/m 2 ·24 hrs to 80 kg/cm, and 100% modulus of said film is 20 kg cm 2 or more.
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) | 1994-07-29 | 1995-01-28 | 1995-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-29 | 1999-01-28 | 1999-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-29 | 2003-01-28 | 2003-07-30 | $7700.00 | Window Closed / Lapsed |