Patent US4859461A successfully refreshed from Google Patents.
US4859461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coatable ion exchange resins
Assignee: Fisons Corp
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Filing: 1987-05-04
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Granted: 1989-08-22
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Expires: 2007-05-04
Abstract
Abstract Sulfonic acid cationic exchange resin particles which have been treated to improve their coatability with up to about 20% by weight of a compound selected from hydroxypropylmethyl cellulose, hydroxypropyl cellulose, hydroxypropyl sorbitol, sorbitol, and polyvinylpyrrolidone.
Inventors
- 👤 San-Laung Chow
- 👤 Yegnaswami Raghunathan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:56
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5036; A61K9/5042; A61K9/5047; A61K47/00; A61K47/50; A61K47/51; A61K47/56; A61K47/58; A61K47/585; A61K9/14; A61K9/16; A61K9/1605; A61K9/1617; A61K9/1623; A61K9/1629; A61K9/1635; A61K9/1652
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
78 words
A process for enhancing the coatability of sulfonic acid cationic exchange resin particles which comprises contacting said particles with an aqueous solution containing from at least about 3% to about 20% by weight of an impregnating agent, based on the combined weight of the impregnating agent and the particles, said agent being selected from the group consisting of hydroxypropylmethyl cellulose, hydroxypropyl cellulose, sorbitol, hydroxypropyl sorbitol, and polyvinylpyrrolidone, and thereafter individually coating said particles with a waterpermeable diffusion barrier.
Claim 2
Dependent Claim
78 words
A process for enhancing the coatability of sulfonic acid cationic exchange resin particles which comprises contacting said particles with an aqueous solution containing from at least about 3% to about 20% by weight of an impregnating agent, based on the combined weight of the impregnating agent and the particles, said agent being selected from the group consisting of hydroxypropylmethyl cellulose, hydroxypropyl cellulose, sorbitol, hydroxypropyl sorbitol, and polyvinylpyrrolidone, and thereafter individually coating said particles with a waterpermeable diffusion barrier.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the impregnating agent is hydroxypropylmethyl cellulose.
Claim 4
Dependent Claim
12 words
The process of claim 1 wherein the impregnating agent is hydroxypropyl cellulose.
Claim 5
Dependent Claim
11 words
The process of claim 1 wherein the impregnating agent is sorbitol.
Claim 6
Dependent Claim
12 words
The process of claim 1 wherein the impregnating agent is hydroxypropyl sorbitol.
Claim 7
Dependent Claim
11 words
The process of claim 1 wherein the impregnating agent is polyvinylpyrrolidone.
References Cited (Backward Citations)
FR803638A
Cited
US2990332A
Cited
GB982150A
Cited
GB1218102A
Cited
DE2246037A1
Cited
US3947572A
Cited
US4221778A
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US4352891A
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DE3012136A1
Cited
EP0171528A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-21 | 1993-02-20 | 1993-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-21 | 1997-02-20 | 1997-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-21 | 2001-02-20 | 2001-08-22 | $7700.00 | Window Closed / Lapsed |