EP0613693A1
Expired / Lapsed
EP
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Swellable wound dressing materials
Assignee: Ethicon Inc
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Filing: 1994-03-02
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Granted: —
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Expires: 2014-03-02
Abstract
Abstract The invention provides water swellable wound dressing materials comprising from 5% to 50% of an alginate ester of a C₁-C₆ polyhydric alcohol; from 50% to 95% of a humectant consisting of one or more C₁-C₆ monohydric or polyhydric alcohols; and from 0% to 30% of water, the percentages being calculated by weight based on the weight of the material when anhydrous. The preferred alginate ester is propylene glycol alginate (PGA). The materials swell but do not dissolve in cold or warm water. Insolubility is achieved by the addition of polyvalent cations such as calcium ions, or by covalent cross-linking of the PGA, or by adding from 10 to 35% by weight of a water-swellable polysaccharide such as gelatin, or by adding from 5% to 20% by weight of a cationic polymer such as chitosan.
Inventors
- 👤 Craig J. Hardy
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 15:41
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/28; A61L26/00; A61L26/0009; A61L26/0023; A61P; A61P17/00
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
71 words
A water swellable wound dressing material comprising, by weight based on the weight of the material when anhydrous: from 5 % to 50% of an alginate ester of a C₁-C₆ polyhydric alcohol; from 50% to 95% of a humectant consisting of one or more C₁-C₆ monohydric or polyhydric alcohols; and from 0% to 30% of water, provided that the wound dressing material comprises less than 1.5% by weight of polyvinyl alcohol.
Claim 2
Dependent Claim
18 words
A water swellable wound dressing material according to claim 1 wherein the alginate ester comprises propylene glycol alginate.
Claim 3
Dependent Claim
26 words
A water swellable wound dressing material according to claim 1 or 2 wherein the degree of esterification of the alginate ester is from 35% to 95%.
Claim 4
Dependent Claim
20 words
A water-swellable wound dressing material according to claim 1, 2 or 3 wherein the humectant comprises glycerol or propylene glycol.
Claim 5
Dependent Claim
24 words
A water-swellable wound dressing material according to any preceding claim wherein the material comprises from 10% to 25% by weight of the alginate ester.
Claim 6
Dependent Claim
23 words
A water-swellable wound dressing material according to any preceding claim wherein the material comprises from 65% to 90% by weight of the humectant.
Claim 7
Dependent Claim
22 words
A water-swellable wound dressing material according to any preceding claim wherein the material comprises from 5% to 15% by weight of water.
Claim 8
Dependent Claim
31 words
A water-swellable wound dressing material according to any preceding claim further comprising from 0% to 25% by weight of one or more substances that are pharmacologically active to promote wound healing.
Claim 9
Dependent Claim
34 words
A water-swellable wound dressing material according to claim 8 wherein the said one or more substances that are pharmacologically active to promote wound healing comprise a cytokine or a biopolymer other than an alginate.
Claim 10
Dependent Claim
20 words
A water-swellable wound dressing material according to any preceding claim further comprising from 0% to 2% of an antimicrobial substance.
Claim 11
Dependent Claim
21 words
A water swellable wound dressing material according to any preceding claim wherein the alginate ester is ionically cross-linked by polyvalent cations.
Claim 12
Dependent Claim
20 words
A water swellable wound dressing material according to claim 11 wherein the polyvalent cations are calcium cations or zinc cations.
Claim 13
Dependent Claim
18 words
A water swellable wound dressing material according to any preceding claim wherein the alginate ester is covalently cross-linked.
Claim 14
Dependent Claim
36 words
A water swellable wound dressing material according to any preceding claim wherein the material further comprises from 5% to 20% by weight based on the weight of the material when anhydrous of a substantially non-esterified alginate.
Claim 15
Dependent Claim
42 words
A water swellable wound dressing material according to any preceding claim wherein the material further comprises from 10% to 35% by weight based on the weight of the material when anhydrous of gelatin or a water swellable polysaccharide other than an alginate.
Claim 16
Dependent Claim
26 words
A water swellable wound dressing material according to claim 15 wherein the water swellable polysaccharide comprises gellan gum, agar, a cellulose derivative or a starch derivative.
Claim 17
Dependent Claim
35 words
A water swellable wound dressing material according to any preceding claim wherein the material further comprises from 5% to 20% by weight based on the weight of the material when anhydrous of a cationic polymer.
Claim 18
Dependent Claim
17 words
A water swellable wound dressing material according to claim 17 wherein the cationic polymer comprises cationic chitosan.
Claim 19
Dependent Claim
20 words
A water swellable wound dressing material according to any preceding claim in the form of a continuous or perforated film.
Claim 20
Dependent Claim
15 words
A water swellable wound dressing material substantially as hereinbefore described with reference to the examples.
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