Patent US3577512A successfully refreshed from Google Patents.
US3577512A
Expired / Lapsed
US
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Sustained release tablets
Assignee: National Patent Development Corp
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Filing: 1968-10-11
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Granted: 1971-05-04
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Expires: 1988-10-11
Abstract
Abstract SUSTAINED RELEASE DOSAGE FORMS, E.G. TABLETS OR PILLS, ARE PREPARED COMPRISING A THERAPEUTICALLY MATERIAL AND A HYDROPHILIC ACRYLATE OR METHACRYLATE POLYMER MIXED THEREWITH AND/OR AS A COATING THEREFOR. PREFERABLY, THE POLYMER IS CROSS-LINKED, MOST PREFERABLY BY EMPLOYING A DIESTER OF THE ACRYLATE OR METHACRYLATE IN MINOR AMOUNTS.
Inventors
- 👤 Thomas H Shepherd
- 👤 Francis E Gould
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:05
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0087; A61K9/0092; A61J; A61J3/00; A61J3/10; A61K9/20; A61K9/2004; A61K9/2022; A61K9/2027; A61K9/2072; A61K9/2086; A61K9/209; A61K9/28; A61K9/2806; A61K9/2833; A61K9/284; A61K9/2846; C; C08; C08K; C08K5/00; C08K5/0008; C08K5/0058
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |