US4599209A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing absorbing wound dressing
Assignee: Leipziger Arzneimittelwerk VEB
•
Filing: 1984-07-05
•
Granted: 1986-07-08
•
Expires: 2004-07-05
Abstract
Abstract A process of making a wound dressing is suggested, in which a technical conventional viscose solution is mixed with a polysaccharide derivative; the mixture is treated at increased temperatures such that it is thermally coagulated; the coagulate is wetted with a polyalkylene glycol and dried, whereby a particulate structure of the wound dressing is produced.
Inventors
- 👤 Horst Dautzenberg
- 👤 Fritz Loth
- 👤 Bodo Borrmeister
- 👤 Dieter Bertram
- 👤 Herbert Lettau
- 👤 Jiri Stamberg
- 👤 Jan Peska
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:19
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/225
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
111 words
Method of making an absorbing wound dressing, comprising the steps of mixing a viscose of technical conventional composition with 50% water soluble carboxylate groups containing polysaccharide derivative in dissolved or solid form selected from the group consisting of sodium carboxymethyl cellulose sodium carboxymethyl starch and sodium alignate, emulsifying said mixture with a dispersion medium which is not mixable with the viscose, then shaping the obtained mixture into specimen by thermal treatment at increased temperatures such that the specimen are coagulated and a particle formation with spherical particles of diameter >10 microns and < one mm occurs therein, removing said dispersion medium from said particles, washing said specimen, and drying said specimen.
Claim 2
Dependent Claim
111 words
Method of making an absorbing wound dressing, comprising the steps of mixing a viscose of technical conventional composition with 50% water soluble carboxylate groups containing polysaccharide derivative in dissolved or solid form selected from the group consisting of sodium carboxymethyl cellulose sodium carboxymethyl starch and sodium alignate, emulsifying said mixture with a dispersion medium which is not mixable with the viscose, then shaping the obtained mixture into specimen by thermal treatment at increased temperatures such that the specimen are coagulated and a particle formation with spherical particles of diameter >10 microns and < one mm occurs therein, removing said dispersion medium from said particles, washing said specimen, and drying said specimen.
Claim 3
Dependent Claim
36 words
Method of making an absorbing wound dressing in accordance with claim 1, wherein the constituent of the carboxylate groups containing polysaccharide derivative with respect to the total weight of said mixture is about 5 to 50%.
Claim 4
Dependent Claim
55 words
Method of making an absorbing wound dressing in accordance with claim 2, wherein the obtained particles are subjected to a wash treatment with a low molecular aliphatic alcohol or ketone, or a mixture thereof, with water or watery solutions, whereby one part of 5 to 50% of the added polysaccharide derivative is again washed out.
Claim 5
Dependent Claim
47 words
Method of making an absorbing wound dressing in accordance with claim 3, wherein glycol or polyethylene glycol are applied to the particles in such a quantity that the constituent of the substances in the end product with respect to the dry polymer mass is 5 to 30%.
Claim 6
Dependent Claim
26 words
Method of making an absorbing wound dressing in accordance with claim 4, wherein glycol or polyethylene glycol are applied to the particles before said drying step.
Claim 7
Dependent Claim
20 words
Method of making an absorbing wound dressing in accordance with claim 1, wherein said increased temperatures are about 90° C.
Claim 8
Dependent Claim
23 words
Method of making an absorbing wound dressing in accordance with claim 1, wherein said removing step is carried out by means of vacuum.
Claim 9
Dependent Claim
92 words
Method of making an absorbing wound dressing, comprising the steps of mixing a viscose of technical conventional composition with 50% water soluble carboxylate groups containing polysaccharide derivative in dissolved or solid form selected from the group consisting of sodium carboxymethyl cellulose sodium carboxymethyl starch and sodium alignate, shaping obtained mixture into specimen by thermal treatment at increased temperatures such that the specimen are coagulated and a particle formation occurs therein, crushing said specimen to granulate spherical particles of diameter >10 microns and < one mm washing said specimen, and drying said specimen.
Claim 10
Dependent Claim
92 words
Method of making an absorbing wound dressing, comprising the steps of mixing a viscose of technical conventional composition with 50% water soluble carboxylate groups containing polysaccharide derivative in dissolved or solid form selected from the group consisting of sodium carboxymethyl cellulose sodium carboxymethyl starch and sodium alignate, shaping obtained mixture into specimen by thermal treatment at increased temperatures such that the specimen are coagulated and a particle formation occurs therein, crushing said specimen to granulate spherical particles of diameter >10 microns and < one mm washing said specimen, and drying said specimen.
Claim 11
Dependent Claim
37 words
Method of making an absorbing wound dressing in accordance with claim 8, wherein the constituent of the carboxylate groups containing polysaccharide derivative with respect to the total weight of the said mixture is about 5 to 50%.
Claim 12
Dependent Claim
20 words
Method of making an absorbing wound dressing in accordance with claim 8, wherein said increased temperatures are about 90° C.
Claim 13
Dependent Claim
55 words
Method of making an absorbing wound dressing in accordance with claim 8, wherein the obtained particles are subjected to a wash treatment with a low molecular aliphatic alcohol or ketone, or a mixture thereof, with water or watery solutions, whereby one part of 5 to 50% of the added polysaccharide derivative is again washed out.
Claim 14
Dependent Claim
47 words
Method of making an absorbing wound dressing in accordance with claim 11, wherein glycol or polyethylene glycol are applied to the particles in such a quantity that the constituent of the substances in the end product with respect to the dry polymer mass is 5 to 30%.
Claim 15
Dependent Claim
26 words
Method of making an absorbing wound dressing in accordance with claim 12, wherein glycol or polethylene glycol are applied to the particles before said drying step.
References Cited (Backward Citations)
US3854981A
Cited
US4058124A
Cited
US4136697A
Cited
US4044766A
Cited
US4090022A
Cited
US4198968A
Cited
US4169121A
Cited
GB2022505A
Cited
US4327728A
Cited
US4340731A
Cited
US4340556A
Cited
US4405324A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-07 | 1990-01-06 | 1990-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-07 | 1994-01-06 | 1994-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-07 | 1998-01-06 | 1998-07-08 | $7700.00 | Window Closed / Lapsed |