US3551556A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carriers for biologically active substances
Assignee: Czech Academy of Sciences
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Filing: 1967-01-06
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Granted: 1970-12-29
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Expires: 1987-01-06
Abstract
Abstract Drugs are released gradually to a living organism after oral ingestion, through a layer of non-ionogenic, neutral hydrogel of a polymer of ethylene glycol methacrylate or similar monomer cross-linked sufficiently to make the polymer insoluble in all gastro intestinal liquids.
Inventors
- 👤 Karel Kliment
- 👤 Jiri Vacik
- 👤 Zdenek Ott
- 👤 Vladimir Majkus
- 👤 Vladimir Stoy
- 👤 Miroslav Stol
- 👤 Otto Wichterle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 16:41
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2004; A61K9/2022; A61K9/2027; C; C08; C08F; C08F36/00; C08F36/02; C08F36/20
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) | 1973-12-28 | 1974-06-29 | 1974-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-12-28 | 1978-06-29 | 1978-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-12-28 | 1982-06-29 | 1982-12-29 | $7700.00 | Window Closed / Lapsed |