Patent US1899861A successfully refreshed from Google Patents.
Patent EP0486294A2 successfully refreshed from Google Patents.
EP0486294A2
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EP
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Compatible blends containing chitosan
Assignee: Iolab Corp
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Filing: 1991-11-14
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Granted: —
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Expires: 2011-11-14
Abstract
Abstract Miscible blends of chitosan having a degree of N-acetylation between about 30 to about 60 percent, and a water soluble polymer. Blends are useful for preparing medical devices, especially ophthalmic devices such as a corneal bandage contact lens.
Inventors
- 👤 Kishore R. Shah
- 👤 Samuel L. Mowbray
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 14:08
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043; A; A61; A61L; A61L17/00; A61L17/06; A61L27/00; A61L27/28; A61L27/34; C; C08; C08L; C08L29/00; C08L29/02; C08L29/04; C08L39/00; C08L39/04; C08L39/06; C08L5/00; C08L5/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
24 words
A composition comprising a mixture of a chitosan having a degree of N-acetylation between about 30 to about 60 percent, and a water-soluble polymer.
Claim 2
Dependent Claim
24 words
A composition comprising a mixture of a chitosan having a degree of N-acetylation between about 30 to about 60 percent, and a water-soluble polymer.
Claim 3
Dependent Claim
20 words
The composition of claim 1 wherein the chitosan has a degree of N-acetylation between about 30 to about 50 percent.
Claim 4
Dependent Claim
22 words
The composition of claim 1 or claim 2 wherein the water-soluble polymer has a weight average molecular weight greater than about 40,000.
Claim 5
Dependent Claim
13 words
The composition of any preceding claim wherein the water-soluble polymer is poly(vinyl alcohol).
Claim 6
Dependent Claim
21 words
The composition of any one of claims 1 to 3 wherein the water-soluble polymer is a pharmaceutical grade of poly(vinyl pyrrolidone).
Claim 7
Dependent Claim
22 words
The composition of any preceding claim wherein the weight ratio of reacetylated chitosan to water-soluble polymer is between 95:5 to about 5:95.
Claim 8
Dependent Claim
23 words
The composition of any preceding claim wherein the weight ratio of reacetylated chitosan to water-soluble polymer is between about 70:30 to about 30:70.
Claim 9
Dependent Claim
13 words
A corneal bandage lens prepared from a composition according to any preceding claims.
Claim 10
Dependent Claim
20 words
The corneal bandage lens of claim 8 wherein substantially completely biodegradation of the lens occurs in less than 7 days.
References Cited (Backward Citations)
No citation records indexed.
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