Patent US4960594A successfully refreshed from Google Patents.
US4960594A
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US
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Polyurethane foam dressing
Assignee: Derma Lock Medical Corp
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Filing: 1988-09-22
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Granted: 1990-10-02
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Expires: 2008-09-22
Abstract
Abstract A polyurethane foam wound dressing and a method for making the dressing is described. The dressing is made from the reaction of a polyurethane prepolymer with a difunctional cross-linking agent in the presence of DMEA and substantial amounts of water. The resulting dressing has a glazed, mirror-smooth surface for application to the wounded area and an insular region to maintain the wound at near body temperature. The dressing has a moisture vapor transmission rate that is close to the capacity of the wound surface to produce serous exudate.
Inventors
- 👤 Travis W. Honeycutt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:28
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/425; A61F; A61F13/00; A61F13/01; A61F13/01034; A61F13/01042; A61F13/01046; A61L15/22; A61L15/26; A61F2013/00089; A61F2013/00157; A61F2013/00246; A61F2013/00263; A61F2013/00361; A61F2013/00365; A61F2013/00519; A61F2013/00727; A61F2013/00731; A61F2013/0074; A61F2013/00855; A61F2013/00876
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
74 words
A wound dressing material consisting essentially of a nonadherent, thin film, foam polyurethane membrane having a substantially smooth surface for application to a wounded area and an insulating region adjacent said smooth surface for maintaining the wound near body temperature, wherein said wound dressing is formed in the presence of a substantial amount of water to enhance CO 2 formation and exhibits a moisture vapor transmission rate greater than 0.30 grams/inch 2 / day.
Claim 2
Dependent Claim
74 words
A wound dressing material consisting essentially of a nonadherent, thin film, foam polyurethane membrane having a substantially smooth surface for application to a wounded area and an insulating region adjacent said smooth surface for maintaining the wound near body temperature, wherein said wound dressing is formed in the presence of a substantial amount of water to enhance CO 2 formation and exhibits a moisture vapor transmission rate greater than 0.30 grams/inch 2 / day.
Claim 3
Dependent Claim
18 words
The wound dressing of claim 1 wherein said membrane has a density less than 0.6 grams/centimeter 3 .
Claim 4
Dependent Claim
20 words
The wound dressing of claim 1 wherein said membrane exhibits an absorbance based on dry weight of greater than 20%.
Claim 5
Dependent Claim
24 words
The wound dressing of claim 1 wherein said membrane is formed by the reaction of a polyurethane prepolymer, a catalyst and a cross-linking agent.
Claim 6
Dependent Claim
60 words
The wound dressing of claim 4 wherein said polyurethane prepolymer is selected from the group consisting of a polyethyelene glycol diol with available isocyanate groups, a polyoxyethylene diol with available isocyanate groups, a mixture of a polyester and a diisocyanate, and a mixture of a polyether, a diisocyanate, and a polyoxypropylene diol capped with at least two diisocyanate end groups.
Claim 7
Dependent Claim
51 words
The wound dressing of claim 5 wherein said catalyst is selected from the group consisting of dimethyaminoethanol, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, glycerol, trimethylolpropane, pentaerythritol, tolylene-2,4,6-triamine, ethylene diamine, amino-ethanol, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, ethanolamine, diethanolamine, hydrazine, triethanolamine, benzene-1,2,4-tricarboxylic acid, nitrilotriacetic acid, citric acid, 4,4'-methylenebis (o-chloroaniline), and organic salts of tin and mercury.
Claim 8
Dependent Claim
29 words
The wound dressing of claim 6 wherein said cross-linking agent is difunctional or greater with two or more terminal groups reactive with isocyanate residues present on said polyurethane prepolymer.
Claim 9
Dependent Claim
27 words
The wound dressing of claim 7 wherein said cross-linking agent is selected from the group consisting of an ethylene glycol/propylene glycol copolymer, silicone polyethylene oxide copolymer, polyethelyeneamines.
Claim 10
Dependent Claim
107 words
A wound dressing material consisting essentially of a nonadherent, thin film, foam polyurethane membrane formed by the reaction of a polyurethane prepolymer with isocyanate residues, a catalyst, and a cross-linking agent with two or more terminal groups reactive with the isocyanate residues, wherein said membrane is formed in the presence of substantial amounts of water to enhance CO 2 formation, and further wherein said membrane exhibits a moisture vapor transmission rate greater than 0.30 grams/inch 2 / day, said membrane further comprising a substantially smooth surface for application to a wounded area and an insulating region adjacent said smooth surface for maintaining the wound near body temperature.
Claim 11
Dependent Claim
107 words
A wound dressing material consisting essentially of a nonadherent, thin film, foam polyurethane membrane formed by the reaction of a polyurethane prepolymer with isocyanate residues, a catalyst, and a cross-linking agent with two or more terminal groups reactive with the isocyanate residues, wherein said membrane is formed in the presence of substantial amounts of water to enhance CO 2 formation, and further wherein said membrane exhibits a moisture vapor transmission rate greater than 0.30 grams/inch 2 / day, said membrane further comprising a substantially smooth surface for application to a wounded area and an insulating region adjacent said smooth surface for maintaining the wound near body temperature.
Claim 12
Independent Claim
108 words
A method for producing a non-adherent, thin film wound dressing material having a substantially smooth surface for application to the wounded area and an insular region adjacent said smooth surface, said method comprising the steps of: reacting a polyurethane prepolymer having isocyanate residues, a catalyst, and a crosslinking agent with two or more terminal groups capable of reacting with the isocyanate residues, to form a mixture; placing the mixture on a substrate; curing the mixture on the substrate in the presence of a substantial amount of water to enhance CO 2 formation to form a membrane with a moisture vapor transmission rate greater than 0.30 grams/inch 2 /day.
Claim 13
Independent Claim
108 words
A method for producing a non-adherent, thin film wound dressing material having a substantially smooth surface for application to the wounded area and an insular region adjacent said smooth surface, said method comprising the steps of: reacting a polyurethane prepolymer having isocyanate residues, a catalyst, and a crosslinking agent with two or more terminal groups capable of reacting with the isocyanate residues, to form a mixture; placing the mixture on a substrate; curing the mixture on the substrate in the presence of a substantial amount of water to enhance CO 2 formation to form a membrane with a moisture vapor transmission rate greater than 0.30 grams/inch 2 /day.
Claim 14
Dependent Claim
24 words
The method of claim 10 wherein the mixture is cured at approximately room temperature and at a relative humidity of between 60 to 80%.
Claim 15
Dependent Claim
17 words
The method of claim 10 wherein said membrane has a density less than 0.6 grams/centimeter 3 .
Claim 16
Dependent Claim
19 words
The method of claim 10 wherein said membrane exhibits an absorbance based on dry weight of greater than 60%.
Claim 17
Dependent Claim
49 words
The wound dressing of claim 4 wherein said polyurethane prepolymer is selected from the group consisting of a polyethyelene glycol diol with available isocyanate groups, a polyoxyethylene diol with available isocyanate groups, a mixture of a polyester and a di-isocyanate, and a mixture of a polyether and a di-isocyanate.
Claim 18
Dependent Claim
50 words
The method of claim 10 wherein said catalyst is selected from the group consisting of dimethyaminoethanol, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, glycerol, trimethylolpropane, pentaerythritol, tolylene-2,4,6-triamine, ethylene diamine, amino-ethanol, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, ethanolamine, diethanolamine, hydrazine, triethanolamine, benzene-1,2,4-tricarboxylic acid, nitrilotriacetic acid, citric acid, 4,4'-methylenebis (o-chloroaniline), and organic salts of tin and mercury.
Claim 19
Dependent Claim
26 words
The method of claim 10 wherein said cross-linking agent is selected from the group consisting of an ethylene glycol/propylene glycol copolymer, silicone polyethylene oxide copolymer, polyethyleneamines.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-10-01 | 1994-04-02 | 1994-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-01 | 1998-04-02 | 1998-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-01 | 2002-04-02 | 2002-10-02 | $7700.00 | Window Closed / Lapsed |