US5089272A
Expired / Lapsed
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Process for producing capsules having a permeability-controllable membrane
Assignee: Snow Brand Milk Products Co Ltd
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Filing: 1989-03-29
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Granted: 1992-02-18
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Expires: 2009-03-29
Abstract
Abstract The present invention relates to a process for producing a microcapsule comprising a permeability-controllable membrane. This process comprises adjusting the ionic strength of a solution of a soluble chitin derivative, and then bringing this solution into contact with a solution of a polyanionic polysaccharide, its salt or a mixture thereof.
Inventors
- 👤 Toshiaki Shioya
- 👤 Ryogo Hirano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:38
CPC Classifications
C; C12; C12N; C12N11/00; C12N11/02; C12N11/04; A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5036; A61K9/5042; A61K9/5047; A61K9/5089; B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
61 words
A process for producing a capsule containing, as a core, a solution (a) of a polyanionic polysaccharide, its salt or a mixture thereof and having a permeability-controllable membrane, said process comprising: preparing a solution (b) of chitosan; dialysing the solution (b); adjusting the ionic strength of the solution (b); and then bringing the solution (a) into contact with the solution (b).
Claim 2
Dependent Claim
61 words
A process for producing a capsule containing, as a core, a solution (a) of a polyanionic polysaccharide, its salt or a mixture thereof and having a permeability-controllable membrane, said process comprising: preparing a solution (b) of chitosan; dialysing the solution (b); adjusting the ionic strength of the solution (b); and then bringing the solution (a) into contact with the solution (b).
Claim 3
Dependent Claim
30 words
The process of claim 1, wherein said polyanionic polysaccharide or its salt is selected from the group consisting of a lower methoxylpectin, carrageenan, carboxymethyl cellulose, sodium alginate and condroitin sulfate.
Claim 4
Dependent Claim
22 words
The process of claim 1, wherein said polyanionic polysaccharide or its salt has a molecular weight of 10 4 -10 6 .
Claim 5
Dependent Claim
18 words
The process of claim 1, wherein the chitosan has a molecular weight of 10 5 -10 6 .
Claim 6
Dependent Claim
23 words
The process of claim 1, wherein said ionic strength of said solution (b) is adjusted by adding a salt to the solution (b).
Claim 7
Dependent Claim
12 words
The process of claim 5, wherein said salt is a neutral salt.
Claim 8
Dependent Claim
23 words
The process of claim 6, wherein said neutral salt is selected from the group consisting of sodium chloride, potassium chloride and lithium chloride.
Claim 9
Dependent Claim
18 words
The process of claim 1, wherein the concentration of the solution (a) is 0.3 to 1.0 wt. %.
Claim 10
Dependent Claim
18 words
The process of claim 1, wherein the concentration of the solution (b) is 0.5 to 1.0 wt. %.
References Cited (Backward Citations)
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) | 1995-02-17 | 1995-08-19 | 1996-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-17 | 1999-08-19 | 2000-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-17 | 2003-08-19 | 2004-02-18 | $7700.00 | Window Closed / Lapsed |